This work was supported by the National Natural Science Foundation of China (81973607 and 81573992).

The investigations described conformed to the Guidelines for the Care and Use of Laboratory Animals of the National Research Council and were approved by the Shanghai University of Traditional Chinese Medicine Animal Care and Use Committee. When performing the experiments, lab coats, disposable nitrile gloves, and goggles are required for safety purposes.
1. Preparation of solvents and estimation of naringenin required for in vivo application
<ol>
	<li>Prepare the following solvents: Tween-80 (final concentration range: 0.5%-1%), DMSO, glycerin (final concentration range: 15%-20%), ethanol (final concentration range: 12% for intramuscular injection)22, and 0.9% PS.</li>
	<li>Estimate the amount of naringenin required based on the dose, number of mice, and injection frequency.
	<ol>
		<li>Order 10 mice (C57BL/6, male, 5 weeks old, SPF) to administer naringenin 5 days a week for 8 weeks. Keep mice in specific pathogen-free (SPF) conditions. 
		NOTE: The dose required for intraperitoneal injection is 20 mg/kg b.w.23.</li>
		<li>Weigh 160 mg of naringenin based on the following calculation: 20 mg/kg x 0.02 kg/mouse x 10 mice x 5 days/week x 8 weeks = 160 mg.</li>
	</ol>
	</li>
	<li>Calculate the concentration of naringenin to be injected in vivo.
	<ol>
		<li>Prepare the recommended volume based on the bodyweight of the mice. The recommended volume of naringenin applied to each mouse is 1% of body weight (0.3 mL). In this experiment, 0.2 mL per mouse was used.</li>
		<li>Calculate the total volume: 0.2 mL per mouse x 10 mice x 5 days/week x 8 weeks = 80 mL.</li>
		<li>Calculate the concentration of the Naringenin in stock: 160 mg/80 mL solvents = 2 mg/mL.</li>
		<li>Calculate the volume for each day: 0.2 mL per mouse x 10 mice = 2 mL.</li>
	</ol>
	</li>
</ol>
2. Dissolution
<ol>
	<li>Ethanol solution
	<ol>
		<li>To prepare naringenin solution at 2 mg/mL, weigh 3.52 mg of naringenin and add it into a 2.0 mL tube. 
		NOTE: To achieve a concentration of 2 mg/mL, the total volume required will be 1760 &#181;L (calculation: 3.52 mg/1760 &#181;L = 2 mg/mL).</li>
		<li>Quickly spin down (2000 x g for 30 s) to make the naringenin powder settle at the bottom of the tube (Figure 1A).</li>
		<li>Add 8.8 &#181;L of 100% ethanol to the tube to prepare a 0.5% (v/v) solution with respect to the total volume required2. Naringenin does not dissolve completely (Figure 1B).</li>
		<li>Continue to add 79.2 &#181;L of 100% ethanol to the tube to prepare a 5% (v/v) solution with respect to the total volume required (calculation: (79.2 &#181;L + 8.8 &#181;L) / 1760 &#181;L x 100% = 5%). Naringenin does not dissolve completely (Figure 1B).</li>
		<li>Add 1672 &#181;L of 0.9% PS to the tube containing 5% ethanol as described in step 2.1.4. This will produce an emulsion (Figure 1D). Centrifuge (2000 x g for 30 s) the solution to check whether naringenin is completely dissolved in the solution. White precipitates of undissolved naringenin appear in the solution (Figure 1E).</li>
	</ol>
	</li>
	<li>DMSO solution
	<ol>
		<li>To prepare naringenin solution at 2 mg/mL, weigh 3.95 mg of naringenin and add into a 2.0 mL tube. 
		&#8203;NOTE: To achieve a concentration of 2 mg/mL, the total volume required will be 1975 &#181;L (calculation: 3.95 mg/1975 &#181;L = 2 mg/mL).</li>
		<li>Quickly spin down (2000 x g for 30 s) to make the naringenin powder settle at the bottom of the tube.</li>
		<li>Add 9.8 &#181;L of DMSO to the tube to prepare a 0.5% (v/v) solution (calculation: 9.8 &#181;L/1975 &#181;L x 100% = 5%). Naringenin dissolves completely (Figure 2A).</li>
		<li>Add 88.2 &#181;L of DMSO to the tube to prepare a 5% (v/v) solution with respect to the total volume required (calculation: (88.2 &#181;L + 9.8 &#181;L) /1975 &#181;L x 100% = 5%). Naringenin dissolves completely (Figure 2B).</li>
		<li>Add 1877 &#181;L of 0.9% PS (v/v percent of 95%) to the solution prepared in step 2.2.4. An emulsion is produced (Figure 1C). Centrifuge (2000 x g for 30 s) the solution to check whether naringenin is completely dissolved in the solution. White precipitates of undissolved naringenin appear in the solution (Figure 1D).</li>
	</ol>
	</li>
	<li>Tween-80 and DMSO solution
	<ol>
		<li>To prepare the naringenin solution at 2 mg/mL, weigh 6.69 mg of naringenin and add into a 5.0 mL tube. 
		&#8203;NOTE: To achieve the final concentration of 2 mg/mL, the total solution volume required will be 3345 &#181;L (calculation: 6.69 mg/3345 &#181;L = 2 mg/mL).</li>
		<li>Quickly spin down (2000 x g for 30 s) to make the naringenin powder settle at the bottom of the tube.</li>
		<li>Add 117.7 &#181;L of DMSO to prepare a 3.5% (v/v) solution with respect to the total volume required (calculation: 117.7 &#181;L /3345 &#181;L x 100% = 3.5%). Naringenin dissolves completely (Figure 3A)</li>
		<li>Add 117.7 &#181;L of Tween 80 to the solution prepared in step 2.3.3 to attain 3.5% (v/v) Tween 80 and 3.5% (v/v) DMSO. Observe the complete dissolution of naringenin (Figure 3B)</li>
		<li>Slowly add the solution prepared in step 2.3.4 to a 5.0 mL tube containing 3109.6 &#181;L of 0.9% PS (v/v percent of 93%) and shake well to obtain an apparent naringenin solution (Figure 3C).</li>
		<li>Let the solution prepared in step 2.3.5 stay at room temperature (RT) for 2 h. The solution is still apparent without any visible precipitates (Figure 3D).</li>
	</ol>
	</li>
	<li>Preparation of naringenin solution for in vivo administration
	<ol>
		<li>According to step 1.2.2, weigh 160 mg of naringenin (160 mg / 2 mg/mL = 80 mL).</li>
		<li>Add 2.8 mL of DMSO to attain 3.5% (v/v) solution (calculation: 2.8 mL / 80 mL x 100% = 3.5%)</li>
		<li>Then, add 2.8 mL of Tween 80 to the solution prepared in step 2.4.2 to attain 3.5% (v/v) Tween 80 and 3.5% (v/v) DMSO.</li>
		<li>Aliquot the solution prepared in step 2.4.3 into four tubes, 1.4 mL per tube [(2.8 mL + 2.8 mL) / 4 = 1.4 mL].</li>
		<li>Aliquot 18.6 mL of 0.9% PS to five 15 mL tubes.</li>
		<li>Store the solution prepared in step 2.4.3 (stock solution) and 2.4.5 at 4 &#176;C (2.8 mL + 2.8 mL + 18.6 mL x 4 = 80 mL).</li>
		<li>Take 140 &#181;L of the stock solution (step 2.4.3) and mix it with 1860 &#181;L of 0.9% PS to prepare 2 mL of naringenin solution for 1 day of administeration.</li>
		<li>Filter the solution through a 0.2 &#181;m filter.</li>
	</ol>
	</li>
</ol>
3. Naringenin solution administration
<ol>
	<li>Handling and restraint
	<ol>
		<li>Spray the cage and hands with 70-75% alcohol before opening the lid. Lift the mouse by the base of the tail and place it on a solid surface to position its tail gently back.</li>
		<li>Grasp the scruff of the neck behind the ears with the left thumb and index finger and position the tail between the little and the ring finger. Keep the mouse in a supine position with its posterior end slightly elevated.</li>
	</ol>
	</li>
	<li>Injection
	<ol>
		<li>Grasp the back skin of the mouse so that the abdominal skin is taut.</li>
		<li>Push the needle (insulin syringe) in at an angle of 10&#176; between the needle and the abdominal surface, in the lower right or left quadrant of the abdomen to avoid hitting the bladder, liver, or other internal organs.</li>
		<li>Run the needle subcutaneously in a cranial direction for 3-5 mm, and then insert it at a 45&#176; angle into the abdominal cavity.</li>
		<li>When the needle passes through the abdominal wall and the resistance disappears, perform an aspiration to confirm that no reflux material is withdrawn. Then, slowly push the solution.</li>
		<li>After the injection, slowly pull the needle out and rotate it slightly to prevent leakage. The recommended volume is 50-100 &#181;L/10 g.</li>
		<li>Dispose of leftover Naringenin in a biohazard container.</li>
	</ol>
	</li>
</ol>
4. Blood glucose test
NOTE: Test the blood glucose 1 day prior to the injection and 1 and 2 months after the injection.
<ol>
	<li>Fast the mice for 15 h before the blood glucose test. Water can continue to be provided.</li>
	<li>Open the test strips and mark the date. Once opened, use the test strips within 3 months. Store the test strips at 2-30 &#176;C. Tightly close the lid after removing the strip to prevent the formation of moisture.</li>
	<li>Place the animal into the induction chamber. Turn on the vaporizer at an induction level of 4% for isoflurane and 4 L/min for oxygen. After the animal is fully anesthetized, maintain the anesthetic with the nose cone and the anesthetic delivery at a level of 1.5% for isoflurane and 0.4 L/min for oxygen.</li>
	<li>Wipe the tail with cotton balls/swabs soaked in 70%-75% alcohol.</li>
	<li>Starting from the lowest point of the tail, make a small puncture on the lateral tail vein with a 25G needle prick and squeeze out a drop of blood.</li>
	<li>Wipe the drop of blood with a tissue paper.</li>
	<li>Squeeze out another drop of blood and collect it on the edge of a test strip.</li>
	<li>Read and record the result displayed on the glucose meter.</li>
	<li>To stop the bleeding, pinch the tail of the mouse with a sterile gauze and wipe the area with 75% alcohol.</li>
	<li>Additional samples may be obtained by a similar technique moving up the tail cranially.</li>
</ol>
5. TRAP staining
<ol>
	<li>Slides preparation
	<ol>
		<li>Perform fasting blood glucose tests on the mice once a week. When the blood glucose levels are &#8805; 11.1 mmol/L (indicative of successful type II diabetes mice model24), euthanize the mice using CO2, followed by cervical disclocation, and collect the Lumbar 4th-6th (L4-L6) (no euthanasia is performed while fasting blood glucose test).</li>
		<li>Fix the L4-L6 samples with 4% paraformaldehyde for 24 h (ensure that the volume of paraformaldehyde is &#62;20x the volume of the tissue), and then wash for 2 h in continuous flow of tap water.</li>
		<li>To decalcify the samples, immerse them in a 10% ethylenediaminetetraacetic acid (EDTA) solution for 2 weeks at RT in static condition until the samples are softened. Ensure that the volume of the decalcifying solution is 20-30 times the volume of the tissue/sample. Change the EDTA solution every other day.</li>
		<li>Dehydrate the sample using a dehydrator.
		<ol>
			<li>Place the specimens in tissue processing embedding cassettes. Number the cassette using a pencil.</li>
			<li>Set the dehydrator program as follows: 75% alcohol for 2 h, 85% alcohol for 1 h, 95% alcohol for 1 h, 95% alcohol for 2 h, anhydrous ethanol (I) for 2 h, anhydrous ethanol (II) for 2 h, anhydrous ethanol (III) for 2 h, xylene (I) for 1 h, xylene (II) for 1 h, xylene (III) for 1 h, paraffin wax (I) for 2 h, and paraffin wax (II) for 2 h, at RT.</li>
		</ol>
		</li>
		<li>Embed the samples in paraffin wax.
		<ol>
			<li>Add paraffin wax to the cassette tray of the paraffin embedding station and heat to 60 &#176;C. Immerse the dehydrated specimens for at least 2 h.</li>
			<li>Place the tissue cassette in the cassette tray and preheat.</li>
			<li>Add paraffin wax to the paraffin reservoir and heat to 60 &#176;C.</li>
			<li>After 2 h, take both tissue cassette and specimens to the work area. Pour the preheated paraffin wax from the paraffin reservoir into the tissue cassette. Place the specimen into the paraffin wax, ensure that the paraffin wax completely covers the tissue, and then immediately move the cassette onto an icing station.</li>
			<li>Use a microtome to cut the paraffin-embedded samples into 5-6 &#181;m sections. Unfold the sections in 40 &#176;C warm water for less than 10 s. Collect the sections on APS (amino silane) coated glass slides. Dry the slides at RT for 1 h, and then move the slides into an oven set at 60 &#176;C for overnight.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>TRAP reagent preparation
	<ol>
		<li>Prepare basic stock incubation solution: Dissolve 9.2 g of sodium acetate anhydrous, 11.4 g of L-(+) tartaric acid, and 2.8 mL of glacial acid in 1000 mL of distilled water. Adjust pH to 4.7-5.0 and store at RT for up to 6 months.</li>
		<li>Prepare Naphthol-ether solution: Dissolve 0.1 g of naphthol AS-BI phosphate in 5 mL of ethylene glycol monoethyl ether. Store at 4 &#176;C for up to 5 weeks.</li>
		<li>Prepare Sodium nitrite solution: Dissolve 1 g of sodium nitrite in 25 mL of distilled water. Store at 4 &#176;C.</li>
		<li>Prepare Pararosaniline dye: Add 1 g of pararosaniline base to 20 mL of 2N HCl (83 mL of HCl in 417 mL of water). Use a stir plate to dissolve the base and filter it before use.</li>
	</ol>
	</li>
	<li>TRAP staining
	<ol>
		<li>Fill two Coplin jars with 50 mL of basic stock incubation solution and place in a 37 &#176;C oven for 2 h.</li>
		<li>Take one Coplin jar and add 0.5 mL of naptol-ether solution.</li>
		<li>Place the slides in the Coplin jar and incubate at 37 &#176;C for 1 h. 
		NOTE: Prepare atleast three slides for each group.</li>
		<li>A few minutes before the incubation time is over, add 1 mL of sodium nitrite solution and 1 mL of pararosaniline dye. Mix gently for 30 s and leave it for 2 min.</li>
		<li>Add the solution prepared in step 5.2.2 to the other preheated Coplin jar containing the basic stock solution. Mix the solution well and insert the slides from the Coplin jar in step 5.3.3.</li>
		<li>Incubate for 15-20 min at RT.</li>
		<li>Rinse the slices in another Coplin jar with 200 mL of PBS for 5 min.</li>
		<li>Counter-stain the slices with 100% hematoxylin for 30 s in a Coplin jar.</li>
		<li>Dehydrate the slices with 85%, 95%, and 100% alcohol (200 mL) for 2 min each and treat in xylene (200 mL) for 2 min for 3x. Use Coplin jars to perform each step.</li>
		<li>Secure the section on the cover glass with a coverslip using resin. Ensure to avoid the trapping of air bubbles.</li>
	</ol>
	</li>
</ol>
6. ELISA
<ol>
	<li>Sample preparation
	<ol>
		<li>Remove the soft tissues from the femur and the tibia of the mouse. Clean the bones with gauze.</li>
		<li>Place the bone samples into a 1 mL microcentrifuge tube and store the sample tubes at -80 &#176;C. 
		NOTE: The samples can also be stored in a liquid nitrogen tank for no more than 6 months.</li>
		<li>Weigh the bone sample. Dilute with 0.9% PS at a ratio of 1:10. For example, dilute 0.1 g of bone with 1 mL of PS.</li>
		<li>Add 3 mm zirconia beads into the tube and grind the samples 3x at 70 Hz for 30 s with 20 s rest in between.</li>
		<li>Centrifuge the samples at 4 &#176;C and 12,000 x g for 5 min. Collect the supernatant.</li>
	</ol>
	</li>
	<li>ELISA assay kit 
	NOTE: Perform ELISA according to the assay protocol specified by the manufacturer.
	<ol>
		<li>Add 100 &#181;L of each dilution of standard, blank, and sample into the appropriate wells. Incubate for 90 min at 37 &#176;C.</li>
		<li>Decant the liquid from each well and add 100 &#181;L of biotinylated detection antibody working solution. Incubate for 1 h at 37 &#176;C.</li>
		<li>Decant the solution, add 350 &#181;L of wash buffer to each well. Soak for 1 min, repeat 3x.</li>
		<li>Add 100 &#181;L of HRP conjugate working solution to each well. Incubate for 30 min at 37 &#176;C.</li>
		<li>Decant the solution. Repeat the wash process 5x as described in step 6.2.3.</li>
		<li>Add 90 &#181;L of the substrate reagent. Incubate for 15 min at 37 &#176;C protected from light.</li>
		<li>Add 50 &#181;L of the stop solution.</li>
	</ol>
	</li>
	<li>Use a plate reader to record the absorbance of each well at 450 nm.</li>
	<li>Standard curve generation
	<ol>
		<li>Plot the respective mean absorbance values against the serially diluted protein concentrations.</li>
		<li>Join the points to create the best fit curve. Use any appropriate computer application (spreadsheet) to generate the standard curve equation.</li>
	</ol>
	</li>
	<li>Substitute the absorbance value of each sample in the standard curve equation to obtain the concentration of the respective sample.</li>
</ol>

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M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Naringenin+adds+to+the+protective+effect+of+L-arginine+in+monocrotaline-induced+pulmonary+hypertension+in+rats:+favorable+modulation+of+oxidative+stress,+inflammation+and+nitric+oxide.">Naringenin adds to the protective effect of L-arginine in monocrotaline-induced pulmonary hypertension in rats: favorable modulation of oxidative stress, inflammation and nitric oxide.</a> European Journal of Pharmaceutical Sciences. 62, 161-170 (2014).</li><li>Park, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Naringenin+ameliorates+kainic+acid-induced+morphological+alterations+in+the+dentate+gyrus+in+a+mouse+model+of+temporal+lobe+epilepsy.">Naringenin ameliorates kainic acid-induced morphological alterations in the dentate gyrus in a mouse model of temporal lobe epilepsy.</a> Neuroreport. 27 (15), 1182-1189 (2016).</li><li>Matsui, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early-stage+Type+2+diabetes+mellitus+impairs+erectile+function+and+neurite+outgrowth+from+the+major+pelvic+ganglion+and+downregulates+the+gene+expression+of+neurotrophic+factors.">Early-stage Type 2 diabetes mellitus impairs erectile function and neurite outgrowth from the major pelvic ganglion and downregulates the gene expression of neurotrophic factors.</a> Urology. 99, 1-7 (2017).</li><li>Sharma, G., Ashhar, M. U., Aeri, V., Katare, D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+and+characterization+of+late-stage+diabetes+mellitus+and+-associated+vascular+complications.">Development and characterization of late-stage diabetes mellitus and -associated vascular complications.</a> Life Sciences. 216, 295-304 (2019).</li><li>Rowe, R. C., Sheskey, P. J., Owen, S. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Handbook of Pharmaceutical Excipients. , (2003).</li><li>Fallahi, F., Roghani, M., Moghadami, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Citrus+flavonoid+naringenin+improves+aortic+reactivity+in+streptozotocin-diabetic+rats.">Citrus flavonoid naringenin improves aortic reactivity in streptozotocin-diabetic rats.</a> Indian Journal of Pharmacology. 44 (3), 382-386 (2012).</li><li>Liu, F., Yang, H., Zhou, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+the+characteristics+of+induced+and+spontaneous+db/db+mouse+models+of+type+2+diabetes+mellitus.">Comparison of the characteristics of induced and spontaneous db/db mouse models of type 2 diabetes mellitus.</a> Acta Laboratorium Animalis Scientia Sinica. 22 (6), 54-59 (2014).</li><li>Liu, S., Dong, J., Bian, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+dual+regulatory+effect+of+naringenin+on+bone+homeostasis+in+two+diabetic+mice+models.">A dual regulatory effect of naringenin on bone homeostasis in two diabetic mice models.</a> Traditional Medicine and Modern Medicine. 03 (02), 101-108 (2020).</li><li>Sun, C., Wu, Z., Wang, Z., Zhang, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+ethanol/water+solvents+on+phenolic+profiles+and+anti-oxidant+properties+of+beijing+propolis+extracts.">Effect of ethanol/water solvents on phenolic profiles and anti-oxidant properties of beijing propolis extracts.</a> Evidence-Based Complementary and Alternative Medicine. 2015, 595393 (2015).</li><li>Huaman-Castilla, N. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+temperature+and+ethanol+concentration+on+the+global+recovery+of+specific+polyphenols+in+an+integrated+HPLE/RP+process+on+carm&#233;n&#232;re+pomace+extracts.">The impact of temperature and ethanol concentration on the global recovery of specific polyphenols in an integrated HPLE/RP process on carm&#233;n&#232;re pomace extracts.</a> Molecules. 24 (17), (2019).</li><li>van Thriel, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toxicology+of+solvents+(including+alcohol).">Toxicology of solvents (including alcohol).</a> Reference Module in Biomedical Sciences. , (2014).</li><li>Linakis, J. G., Cunningham, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+concentration+of+ethanol+injected+intraperitoneally+on+taste+aversion,+body+temperature,+and+activity.">Effects of concentration of ethanol injected intraperitoneally on taste aversion, body temperature, and activity.</a> Psychopharmacology. 64 (1), 61-65 (1979).</li><li>Magwaza, L. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+methods+for+extracting+and+quantifying+phenolic+compounds+in+citrus+rinds.">Rapid methods for extracting and quantifying phenolic compounds in citrus rinds.</a> Food Science &amp; Nutrition. 4 (1), 4-10 (2016).</li><li>Smith, E. R., Hadidian, Z., Mason, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+single--and+repeated--dose+toxicity+of+dimethyl+sulfoxide.">The single--and repeated--dose toxicity of dimethyl sulfoxide.</a> Annals of the New York Academy of Sciences. 141 (1), 96-109 (1967).</li><li>Colucci, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+insights+of+dimethyl+sulphoxide+effects+(DMSO)+on+experimental+in+vivo+models+of+nociception+and+inflammation.">New insights of dimethyl sulphoxide effects (DMSO) on experimental in vivo models of nociception and inflammation.</a> Pharmacological Research. 57 (6), 419-425 (2008).</li><li>Kawakami, K., Oda, N., Miyoshi, K., Funaki, T., Ida, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Solubilization+behavior+of+a+poorly+soluble+drug+under+combined+use+of+surfactants+and+co-solvents.">Solubilization behavior of a poorly soluble drug under combined use of surfactants and co-solvents.</a> European Journal of Pharmaceutical Sciences. 28 (1-2), 7-14 (2006).</li></ol>

The authors have nothing to disclose.

The preparation of phytochemical solution is the basis for its application in vivo. In this protocol, the preparation of naringenin solution was demonstrated by using different solvents, such as ethanol, DMSO, Tween 80, and 0.9% PS. The solution in completely dissolved status needs to be further monitored by allowing it to remain at room temperature for some extended hours, and then filtered before being used in vivo.
Solvent determination is a critical step in this protocol....

With increasing studies concerning the use of phytochemical compounds for drug screening, approaches to prepare phytochemical solutions to evaluate their optimal effects are worth giving attention to. Many aspects such as the dissolution methodology, dosage, and concentration&#160;are to be considered when preparing the compound1.
Solvent-based dissolution is widely used for organic compound preparation1. The commonly used solvents include water, oil, dimethyl sulfoxide (DMSO), methanol, ethanol, formic acid, Tween, glycerin, etc2. Although a suspension with undissolved substances is acceptable when the compound is administered by gastric gavage, a fully dissolved solute is critical for intravenous administration. Since oil solution, suspension, and emulsion can cause capillary embolisms, an aqueous solution for compound preparation is suggested, especially when administering intravenous, intramuscular, and intraperitoneal injections3.
The effective dose range varies among compounds and even among diseases treated with the same compound. Determinations of the effective and the safe dose and the concentration are dependant on literature and preliminary experiments4. Here, the preparation of the compound naringenin is demonstrated as an example.
Naringenin (4,5,7-trihydroxy-flavanone), a polyphenolic compound, has been studied in disease treatment for its hepatoprotective5, antidiabetic6, anti-inflammatory7, and anti-oxidant activities8. For in vivo applications, the oral administration of naringenin is commonly used. Previous studies reported preparing naringenin solution in 0.5%-1% carboxymethyl cellulose, 0.5% methylcellulose dose, 0.01% DMSO, and physiological saline (PS) at 50-100 mg/kg, administered by oral gavage9,10,11,12. Besides, other studies have reported supplementing naringenin with chow at 3% (wt/wt) for oral intake at a dose of 3.6 g/kg/d13,14. Studies have also reported using ethanol (0.5% v/v), PS, and DMSO to dissolve naringenin for intraperitoneal injection at 10-50 mg/kg15,16,17,18. In a study of temporal lobe epilepsy, mice received an injection of naringenin suspended in 0.25% carboxymethyl cellulose dissolved in PS19. Though these studies report the use of different solvents to prepare naringenin solutions, further details, such as dissolving status and animal response, have not been reported.
This protocol introduces a procedure for preparing naringenin solution for in vivo application in diabetic-induced osteoporosis. The preparation of the injection solution includes preparing solvents and compounds, dosage estimation, dissolution process, and filtration. The dosage was determined based on literature research and preliminary experiments by monitoring mice after administering injections every day for 3 days and modifying the dosage according to mouse behaviors. The final chosen concentration (20 mg/kg b.w.) was administered intraperitoneally 5 days per week for 8 weeks in a high-fat diet and streptozotocin (STZ)-induced diabetic mice20,21. The effects of naringenin in diabetic osteoporosis were evaluated by blood glucose testing, micro-CT, tartrate-resistant acid phosphatase (TRAP) staining, and enzyme-linked immunosorbent assay (ELISA).
Overall, it was observed that naringenin at a concentration range of 40-400 mg/mL did not completely dissolve in either ethanol or DMSO or 5% (ethanol or DMSO) plus 95% PS (v/v). However, naringenin dissolved completely in a mixture of 3.52% DMSO, 3.52% Tween 80, and 92.96% PS. The detailed procedure will help researchers to prepare the compound as an injection solution for in vivo application.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1.5 mL&#160; microtubes</td>
			<td>Corning Science (Wujiang) Co.</td>
			<td>23218392</td>
			<td>Holding liquid</td>
		</tr>
		<tr>
			<td>Automatic Dehydrator</td>
			<td>Leica Microsystems (Shanghai) Co.</td>
			<td>LEICA ASP 300S</td>
			<td>Dehydrate samples</td>
		</tr>
		<tr>
			<td>Blood glucose test strips</td>
			<td>Johnson &#38; Johnson (China) Medical Equipment Co.</td>
			<td>4130392</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge</td>
			<td>MIULAB</td>
			<td>Minute centrifuge</td>
			<td>Centrifugal solution</td>
		</tr>
		<tr>
			<td>Dehydrator</td>
			<td>Leica Microsystems (Shanghai) Trading Co.</td>
			<td>LEICA&#160; ASP300S</td>
			<td>Dehydration</td>
		</tr>
		<tr>
			<td>DMSO</td>
			<td>Sangon Biotech (Shanghai ) Co.,Ltd.</td>
			<td>E918BA0041</td>
			<td>Co-Solvent</td>
		</tr>
		<tr>
			<td>ELISA assay kit</td>
			<td>Elabscience Biotechnology Co.,Ltd</td>
			<td>Mouse COL1(Collagen Type I) ELISA Kit: E-EL-M0325c 
			Mouse&#160; CTX I ELISA Kit: E-EL-M0366c 
			Mouse PICP ELISA Kit: E-EL-M0231c 
			Mouse PINP ELISA Kit: E-EL-M0233c</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol absolute</td>
			<td>Sinopharm Chemical ReagentCo., Ltd</td>
			<td>10009218</td>
			<td>Co-Solvent</td>
		</tr>
		<tr>
			<td>Ethylene glycol monoethyl ether</td>
			<td>Sangon Biotech (Shanghai ) Co.,Ltd.</td>
			<td>A501118-0500</td>
			<td>TRAP staining</td>
		</tr>
		<tr>
			<td>Ethylenediaminetetraacetic acid (EDTA)</td>
			<td>Sinopharm Chemical ReagentCo., Ltd</td>
			<td>10009617</td>
			<td>Decalcification</td>
		</tr>
		<tr>
			<td>Filter</td>
			<td>Merck Millpore LTD.</td>
			<td>Millex-GP, 0.22 &#181;m</td>
			<td>filter solution</td>
		</tr>
		<tr>
			<td>Glacial acid</td>
			<td>Sinopharm Chemical ReagentCo., Ltd</td>
			<td>10000218</td>
			<td>TRAP staining</td>
		</tr>
		<tr>
			<td>Glucose meter</td>
			<td>Johnson &#38; Johnson (China) Medical Equipment Co.</td>
			<td>One Touch Ultra Vue</td>
			<td>Serial number:COJJG8GW</td>
		</tr>
		<tr>
			<td>Grinder</td>
			<td>Shanghaijingxin Experimental Technology</td>
			<td>Tissuelyser-24</td>
			<td></td>
		</tr>
		<tr>
			<td>Hematoxylin</td>
			<td>Nanjing Jiancheng Bioengineering Institute</td>
			<td>D005</td>
			<td>TRAP staining</td>
		</tr>
		<tr>
			<td>Insulin syringe</td>
			<td>Shanghai Kantaray Medical Devices Co.</td>
			<td>0.33 mm x 13 mm, RW LB</td>
			<td>Intraperitoneal injection</td>
		</tr>
		<tr>
			<td>L-(+) tartaric acid</td>
			<td>Sinopharm Chemical ReagentCo., Ltd</td>
			<td>100220008</td>
			<td>TRAP staining</td>
		</tr>
		<tr>
			<td>Microscope</td>
			<td>OLYMPUS</td>
			<td>sz61</td>
			<td>Observation</td>
		</tr>
		<tr>
			<td>Microtome</td>
			<td>Leica Microsystems (Shanghai) Trading Co.</td>
			<td>LEICA RM 2135</td>
			<td>Section</td>
		</tr>
		<tr>
			<td>Mini centrifuge</td>
			<td>Hangzzhou Miu Instruments Co., Ltd.</td>
			<td>&#160;Mini-6KC</td>
			<td>Centrifuge</td>
		</tr>
		<tr>
			<td>Naphthol AS-BI phosphate</td>
			<td>SIGMA-ALDRICH</td>
			<td>BCBS3419</td>
			<td>TRAP staining</td>
		</tr>
		<tr>
			<td>Naringenin</td>
			<td>Jiangsu Yongjian Pharmaceutical Co.,Ltd</td>
			<td>102764</td>
			<td>Solute</td>
		</tr>
		<tr>
			<td>Paraffin Embedding station</td>
			<td>Leica Microsystems (Shanghai) Co.</td>
			<td>LEICA&#160; EG 1150 H, LEICA&#160; EG 1150 C</td>
			<td>Embed&#160; samples</td>
		</tr>
		<tr>
			<td>Pararosaniline base</td>
			<td>BBI Life Sciences</td>
			<td>E112BA0045</td>
			<td>TRAP staining</td>
		</tr>
		<tr>
			<td>Pipettes</td>
			<td>eppendorf</td>
			<td>2&#8211;20 &#181;L, 100&#8211;1000 &#181;L, 20&#8211;200 &#181;L</td>
			<td>&#160; transferre Liquid</td>
		</tr>
		<tr>
			<td>Plate reader</td>
			<td>BioTek Instruments USA, Inc.</td>
			<td>BioTek CYTATION 3 imaging reader</td>
			<td>ELISA</td>
		</tr>
		<tr>
			<td>Resin</td>
			<td>Shanghai Yyang Instrument Co., Ltd.</td>
			<td>Neutral balsam</td>
			<td>TRAP staining</td>
		</tr>
		<tr>
			<td>saline (0.9 PS)</td>
			<td>Baxter Healthcare (Shanghai) Co.,Ltd</td>
			<td>A6E1323</td>
			<td>Solvent</td>
		</tr>
		<tr>
			<td>Sodium acetate anhydrous</td>
			<td>Sinopharm Chemical ReagentCo., Ltd</td>
			<td>Merck-1.06268.0250 | 250g</td>
			<td>TRAP staining</td>
		</tr>
		<tr>
			<td>Sodium nitrite</td>
			<td>Sinopharm Chemical ReagentCo., Ltd</td>
			<td>10020018</td>
			<td>TRAP staining</td>
		</tr>
		<tr>
			<td>Tween-80</td>
			<td>Sangon Biotech (Shanghai ) Co.,Ltd.</td>
			<td>E819BA0006</td>
			<td>Emulsifier</td>
		</tr>
		<tr>
			<td>Zirconia beads</td>
			<td>Shanghaijingxin Experimental Technology</td>
			<td>11079125z 454g</td>
			<td>Grinding</td>
		</tr>
	</tbody>
</table>

preparation of naringenin solution for in vivo application

The preparation of a compound (phytochemical) solution is an overlooked but critical step prior to its application in studies such as drug screening. The complete solubilization of the compound is necessary for its safe use and relatively stable results. Here, a protocol for preparing naringenin solution and its intraperitoneal administration in a high-fat diet and streptozotocin (STZ)-induced diabetic model is demonstrated as an example. A small amount of naringenin (3.52-6.69 mg) was used to test its solubilization in solvents, including ethanol, dimethylsulfoxide (DMSO), and DMSO plus Tween 80 reconstituted in physiological saline (PS), respectively. Complete solubilization of the compound is determined by observing the color of the solution, the presence of precipitates after centrifugation (2000 x g for 30 s), or allowing the solution to stand for 2 h at room temperature (RT). After obtaining a stable compound/phytochemical solution, the final concentration/amount of the compound required for in vivo studies can be prepared in a solvent-only (no PS) stock solution, and then diluted/mixed with PS as desired. The antidiabetic osteoporotic effects of naringenin in mice (intraperitoneal administration at 20 mg/kg b.w., 2 mg/mL) were assessed by measuring blood glucose, bone mass (micro-CT), and bone resorption rate (TRAP staining and ELISA). Researchers looking for detailed organic/phytochemical solution preparations will benefit from this technique.

The bodyweight of the high-fat diet-fed and STZ-induced diabetic mice was found to decrease when compared with that of the control groups from 0-8 weeks after STZ treatment. The weight loss of naringenin-treated mice was significant compared to the nontreated mice (STZ group) at week 4. The control and STZ groups were administered with the same volume of PS (Table 1). The blood glucose level in diabetic mice dramatically increased within 1 month after STZ induction. It then automatically decreased to a l...

Watch this Scientific Journal Video about Preparation of Naringenin Solution for In Vivo Application at JoVE.com

Preparation of Naringenin Solution for In Vivo Application

Here, the protocol presents the preparation of naringenin solution for in vivo intraperitoneal administration. Naringenin is fully dissolved in a mixture of dimethylsulfoxide, Tween 80, and saline. The antidiabetic osteoporotic effects of naringenin were assessed by blood glucose testing, tartrate-resistant acid phosphatase staining, and enzyme-linked immunosorbent assay.

Preparation of Naringenin Solution for In Vivo Application

The preparation of a compound (phytochemical) solution is an overlooked but critical step prior to its application in studies such as drug screening. The ...

preparation-of-naringenin-solution-for-in-vivo-application

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3.2K Views.  Shanghai University of Traditional Chinese Medicine. Here, the protocol presents the preparation of naringenin solution for in vivo intraperitoneal administration. Naringenin is fully dissolved in a mixture of dimethylsulfoxide, Tween 80, and saline. The antidiabetic osteoporotic effects of naringenin were assessed by blood glucose testing, tartrate-resistant acid phosphatase staining, and enzyme-linked immunosorbent assay.

Video: Preparation of Naringenin Solution for In Vivo Application

In vivo 19F MRI for Cell Tracking

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. Here, we describe a general protocol for cell labeling, imaging, and image processing. The technique is applicable to various cell types and animal models, although here we focus on a typical mouse model for tracking murine immune cells. The most important issues for cell labeling are described, as these are relevant to all models. Similarly, key imaging parameters are listed, although the details will vary depending on the MRI system and the individual setup. Finally, we include an image processing protocol for quantification. Variations for this, and other parts of the protocol, are assessed in the Discussion section. Based on the detailed procedure described here, the user will need to adapt the protocol for each specific cell type, cell label, animal model, and imaging setup. Note that the protocol can also be adapted for human use, as long as clinical restrictions are met.

In vivo 19F MRI for Cell Tracking

We describe a general protocol for in vivo cell tracking using MRI in a mouse model with ex vivo labeled cells. A typical protocol for cell labeling, image acquisition processing and quantification is included.

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. ...

Glaucoma-inducing Procedure in an In Vivo Rat Model and Whole-mount Retina Preparation

Glaucoma is a disease of the central nervous system affecting retinal ganglion cells (RGCs). RGC axons making up the optic nerve carry visual input to the brain for visual perception. Damage to RGCs and their axons leads to vision loss and/or blindness. Although the specific cause of glaucoma is unknown, the primary risk factor for the disease is an elevated intraocular pressure. Glaucoma-inducing procedures in animal models are a valuable tool to researchers studying the mechanism of RGC death. Such information can lead to the development of effective neuroprotective treatments that could aid in the prevention of vision loss. The protocol in this paper describes a method of inducing glaucoma - like conditions in an in vivo rat model where 50 &#181;l of 2 M hypertonic saline is injected into the episcleral venous plexus. Blanching of the vessels indicates successful injection. This procedure causes loss of RGCs to simulate glaucoma. One month following injection, animals are sacrificed and eyes are removed. Next, the cornea, lens, and vitreous are removed to make an eyecup. The retina is then peeled from the back of the eye and pinned onto sylgard dishes using cactus needles. At this point, neurons in the retina can be stained for analysis. Results from this lab show that approximately 25% of RGCs are lost within one month of the procedure when compared to internal controls. This procedure allows for quantitative analysis of retinal ganglion cell death in an in vivo rat glaucoma model.

Glaucoma-inducing Procedure in an In Vivo Rat Model and Whole-mount Retina Preparation

Glaucoma is characterized by damage to retinal ganglion cells. Inducing glaucoma in animal models can provide insight into the study of this disease. Here, we outline a procedure that induces loss of RGCs in an in vivo rat model and demonstrates the preparation of whole-mount retinas for analysis.

Glaucoma is a disease of the central nervous system affecting retinal ganglion cells (RGCs). RGC axons making up the optic nerve carry visual input to the ...

Generation of Microtumors Using 3D Human Biogel Culture System and Patient-derived Glioblastoma Cells for Kinomic Profiling and Drug Response Testing

The use of patient-derived xenografts for modeling cancers has provided important insight into cancer biology and drug responsiveness. However, they are time consuming, expensive, and labor intensive. To overcome these obstacles, many research groups have turned to spheroid cultures of cancer cells. While useful, tumor spheroids or aggregates do not replicate cell-matrix interactions as found in vivo. As such, three-dimensional (3D) culture approaches utilizing an extracellular matrix scaffold provide a more realistic model system for investigation. Starting from subcutaneous or intracranial xenografts, tumor tissue is dissociated into a single cell suspension akin to cancer stem cell neurospheres. These cells are then embedded into a human-derived extracellular matrix, 3D human biogel, to generate a large number of microtumors. Interestingly, microtumors can be cultured for about a month with high viability and can be used for drug response testing using standard cytotoxicity assays such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and live cell imaging using Calcein-AM. Moreover, they can be analyzed via immunohistochemistry or harvested for molecular profiling, such as array-based high-throughput kinomic profiling, which is detailed here as well. 3D microtumors, thus, represent a versatile high-throughput model system that can more closely replicate in vivo tumor biology than traditional approaches.

Patient-derived xenografts of glioblastoma multiforme can be miniaturized into living microtumors using 3D human biogel culture system. This in vivo-like 3D tumor assay is suitable for drug response testing and molecular profiling, including kinomic analysis.

The use of patient-derived xenografts for modeling cancers has provided important insight into cancer biology and drug responsiveness. However, they are ...

Depletion of Mouse Cells from Human Tumor Xenografts Significantly Improves Downstream Analysis of Target Cells

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic patient tumors in different assays1. Human tumor xenografts represent the gold standard with respect to tumor biology, drug discovery, and metastasis research 2-4. Tumor xenografts can be derived from different types of material like tumor cell lines, tumor tissue from primary patient tumors4 or serially transplanted tumors. When propagated in vivo, xenografted tissue is infiltrated and vascularized by cells of mouse origin. Multiple factors such as the tumor entity, the origin of xenografted material, growth rate and region of transplantation influence the composition and the amount of mouse cells present in tumor xenografts. However, even when these factors are kept constant, the degree of mouse cell contamination is highly variable.
Contaminating mouse cells significantly impair downstream analyses of human tumor xenografts. As mouse fibroblasts show high plating efficacies and proliferation rates, they tend to overgrow cultures of human tumor cells, especially slowly proliferating subpopulations. Mouse cell derived DNA, mRNA, and protein components can bias downstream gene expression analysis, next-generation sequencing, as well as proteome analysis 5. To overcome these limitations, we have developed a fast and easy method to isolate untouched human tumor cells from xenografted tumor tissue. This procedure is based on the comprehensive depletion of cells of mouse origin by combining automated tissue dissociation with the benchtop tissue dissociator and magnetic cell sorting. Here, we demonstrate that human target cells can be can be obtained with purities higher than 96% within less than 20 min independent of the tumor type.

Human tumor xenografts are vascularized and infiltrated by cells of mouse origin during the growth phase in vivo. To circumvent the bias caused by these contaminating cells during downstream analysis, we developed a method allowing for comprehensive depletion of all mouse cells by magnetic cell sorting.

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic ...

Optimized Analysis of In Vivo and In Vitro Hepatic Steatosis

Establishing a system of procedures to qualitatively and quantitatively characterize in vivo and in vitro hepatic steatosis is important for metabolic study in the liver. Here, numerous assays are described to comprehensively measure the phenotype and parameters of hepatic steatosis in mouse and hepatocyte models. 
Combining the physiological, histological, and biochemical methods, this system can be used to assess the progress of hepatic steatosis. In vivo, the measurements of body weight and nuclear magnetic resonance (NMR) provide a general understanding of mice in a non-invasive manner. Hematoxylin and Eosin (H&amp;E) and Oil Red O staining determine the histological morphology and lipid deposition of liver tissue under nutrient overload conditions, such as high-fat diet feeding. Next, the total lipid contents are isolated by chloroform/methanol extraction, which are followed by a biochemical analysis for triglyceride and cholesterol. Moreover, mouse primary hepatocytes are treated with high glucose plus insulin to stimulate lipid accumulation, an efficient in vitro model to mimic diet-induced hyperglycemia and hyperinsulinemia in vivo. Then, the lipid deposition is measured by Oil Red O staining and chloroform/methanol extraction. Oil Red O staining determines intuitive hepatic steatotic phenotypes, while the lipid extraction analysis determines the parameters that can be analyzed statistically. The present protocols are of interest to scientists in the fields of fatty liver diseases, insulin resistance, and type 2 diabetes.

Optimized Analysis of In Vivo and In Vitro Hepatic Steatosis

Here, optimized methods to generate in vivo and in vitro models of hepatic steatosis and to analyze the steatotic phenotypes and related physiological parameters are described.

Establishing a system of procedures to qualitatively and quantitatively characterize in vivo and in vitro hepatic steatosis is important for metabolic ...

Preparation of Herbal Medicine: Er-Xian Decoction and Er-Xian-containing Serum for In Vivo and In Vitro Experiments

Traditional herbal medicine, an alternative medicine in the clinical setting, has received increased attention in recent years. Before delivery to the body, an additional extraction procedure is commonly required to release the active constituents from raw herbs. Water decoction is a classical extraction procedure that is still broadly used in the clinical settings. Here, we propose a detailed protocol for er-xian decoction (EXD) in order to apply herbal decoctions to experimental studies. The calculation of an animal-appropriate dose is described, as well as the four main steps of EXD: soaking, water decoction, filtration, and concentration. In addition, serum-containing EXD is introduced to rats as a means of in vitro validation. Here, rats were orally administered EXD for three days. Blood samples were then collected, inactivated, centrifuged, and filtered. The serum, diluted with the culture medium, can be utilized to treat cells or tissues in vitro. For example, EXD was applied to both in vivo and in vitro studies and demonstrated that EXD enhances osteogenesis. This protocol can be used as a reference for the preparation and application of herbal medicines.

Preparation of Herbal Medicine: Er-Xian Decoction and Er-Xian-containing Serum for In Vivo and In Vitro Experiments

Here, we present the preparation of an er-xian decoction (EXD) in four steps&#8212;soaking, decoction, filtration, and concentration&#8212;and demonstrate the administration of a prepared EXD-containing serum to rats. These methods are applicable to the in vivo and in vitro study of herbal decoctions such as traditional Chinese medicines.

Traditional herbal medicine, an alternative medicine in the clinical setting, has received increased attention in recent years. Before delivery to the ...

Preparation Steps for Measurement of Reactivity in Mouse Retinal Arterioles Ex Vivo

Vascular insufficiency and alterations in normal retinal perfusion are among the major factors for the pathogenesis of various sight-threatening ocular diseases, such as diabetic retinopathy, hypertensive retinopathy, and possibly glaucoma. Therefore, retinal microvascular preparations are pivotal tools for physiological and pharmacological studies to delineate the underlying pathophysiological mechanisms and to design therapies for the diseases. Despite the wide use of mouse models in ophthalmic research, studies on retinal vascular reactivity are scarce in this species. A major reason for this discrepancy is the challenging isolation procedures owing to the small size of these retinal blood vessels, which is ~ &#8804; 30 &#181;m in luminal diameter. To circumvent the problem of direct isolation of these retinal microvessels for functional studies, we established an isolation and preparation technique that enables ex vivo studies of mouse retinal vasoactivity under near-physiological conditions. Although the present experimental preparations will specifically refer to the mouse retinal arterioles, this methodology can readily be employed to microvessels from rats.

Preparation Steps for Measurement of Reactivity in Mouse Retinal Arterioles Ex Vivo

Many vision-threatening ocular diseases are associated with dysfunctional retinal microvessels. Therefore, the measurement of retinal arteriole responses is important to investigate the underlying pathophysiological mechanisms. This article describes a detailed protocol for mouse retinal arteriole isolation and preparation to assess the effects of vasoactive substances on vascular diameter.

Vascular insufficiency and alterations in normal retinal perfusion are among the major factors for the pathogenesis of various sight-threatening ocular ...

Whole-brain Segmentation and Change-point Analysis of Anatomical Brain MRI&#8212;Application in Premanifest Huntington's Disease

Recent advances in MRI offer a variety of useful markers to identify neurodegenerative diseases. In Huntington&#39;s disease (HD), regional brain atrophy begins many years prior to the motor onset (during the &#34;premanifest&#34; period), but the spatiotemporal pattern of regional atrophy across the brain has not been fully characterized. Here we demonstrate an online cloud-computing platform, &#34;MRICloud&#34;, which provides atlas-based whole-brain segmentation of T1-weighted images at multiple granularity levels, and thereby, enables us to access the regional features of brain anatomy. We then describe a regression model that detects statistically significant inflection points, at which regional brain atrophy starts to be noticeable, i.e. the &#34;change-point&#34;, with respect to a disease progression index. We used the CAG-age product (CAP) score to index the disease progression in HD patients. Change-point analysis of the volumetric measurements from the segmentation pipeline, therefore, provides important information of the order and pattern of structural atrophy across the brain. The paper illustrates the use of these techniques on T1-weighted MRI data of premanifest HD subjects from a large multicenter PREDICT-HD study. This design potentially has wide applications in a range of neurodegenerative diseases to investigate the dynamic changes of brain anatomy.

Whole-brain Segmentation and Change-point Analysis of Anatomical Brain MRI&amp;#8212;Application in Premanifest Huntington&#039;s Disease

This paper describes a statistical model for volumetric MRI data analysis, which identifies the &#34;change-point&#34; when brain atrophy begins in premanifest Huntington&#39;s disease. Whole-brain mapping of the change-points is achieved based on brain volumes obtained using an atlas-based segmentation pipeline of T1-weighted images.

Recent advances in MRI offer a variety of useful markers to identify neurodegenerative diseases. In Huntington&#39;s disease (HD), regional brain atrophy ...

Preparation Of Gushukang (GSK) Granules for In Vivo and In Vitro Experiments

Traditional Chinese herbal medicine plays a role as an alternative method in treating many diseases, such as postmenopausal osteoporosis (POP). Gushukang (GSK) granules, a marketed prescription in China, have bone-protective effects in treating POP. Before administration to the body, one standard preparation procedure is commonly required, which aims to promote the release of active constituents from raw herbs and enhance the pharmacological effects as well as therapeutic outcomes. This study proposes a detailed protocol for using GSK granules in in vivo and in vitro experimental assays. The authors first provide a detailed protocol to calculate the animal-appropriate dosages of granules for in vivo investigation: weighing, dissolving, storage, and administration. Second, this article describes protocols for micro-CT scanning and the measurement of bone parameters. Sample preparation, protocols for running the micro-CT machine and quantification of bone parameters were evaluated. Third, serum-containing GSK granules are prepared, and drug-containing serum is extracted for in vitro osteoclastogenesis and osteoblastogenesis. GSK granules were intragastrically administered twice per day to rats for three consecutive days. Blood was then collected, centrifuged, inactivated, and filtered. Finally, serum was diluted and used for performing osteoclastogenesis and osteoblastogenesis. The protocol described here can be considered a reference for pharmacological investigations of herbal prescription medicines, such as granules.

Preparation Of Gushukang GSK Granules for In Vivo and In Vitro Experiments

This article provides a detailed protocol for preparing a working solution of Gushukang granules for animal studies and GSK granule containing serum for in vitro experiments. This protocol can be applied to pharmacological investigations of herbal medicines as well as prescriptions for both in vivo and in vitro experiments.

Traditional Chinese herbal medicine plays a role as an alternative method in treating many diseases, such as postmenopausal osteoporosis (POP). Gushukang ...

A Rat Carotid Artery Pressure-Controlled Segmental Balloon Injury with Periadventitial Therapeutic Application

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the luminal surface area in arteries thereby reducing adequate blood flow to organs and distal tissues. Clinically, revascularization procedures such as balloon angioplasty with or without stent placement aim to restore blood flow. Although these procedures reestablish blood flow by reducing plaque burden, they damage the vessel wall, which initiates the arterial healing response. The prolonged healing response causes arterial restenosis, or re-narrowing, ultimately limiting the long-term success of these revascularization procedures. Therefore, preclinical animal models are integral for analyzing the pathophysiological mechanisms driving restenosis, and provide the opportunity to test novel therapeutic strategies. Murine models are cheaper and easier to operate on than large animal models. Balloon or wire injury are the two commonly accepted injury modalities used in murine models. Balloon injury models in particular mimic the clinical angioplasty procedure and cause adequate damage to the artery for the development of restenosis. Herein we describe the surgical details for performing and histologically analyzing the modified, pressure-controlled rat carotid artery balloon injury model. Additionally, this protocol highlights how local periadventitial application of therapeutics can be used to inhibit neointimal hyperplasia. Lastly, we present light sheet fluorescence microscopy as a novel approach for imaging and visualizing the arterial injury in three-dimensions.

The rat carotid artery balloon injury mimics the clinical angioplasty procedure performed to restore blood flow in atherosclerotic vessels. This model induces the arterial injury response by distending the arterial wall, and denuding the intimal layer of endothelial cells, ultimately causing remodeling and an intimal hyperplastic response.

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the ...