This work has been supported by the second batch of special scientific research projects of the National Clinical Research Base of Traditional Chinese Medicine (JDZX2015127, based on Anhui Provincial Hospital of Chinese Medicine).

All animal experiments were approved by the Animal Care and Use Committee of the Nanjing University of Chinese Medicine (permission no. 202209A033). Healthy male C57BL/6J mice with SPF grade, 8 weeks of age, and body weight of 20 &#177; 4 g were selected. The mice were housed in a 12 h light/dark cycle at a temperature of 20-22 &#176;C, and a relative humidity of 45%-50% was maintained. The animals eat and drink freely.
1. Establishment of a mouse model of T2DM
<ol>
	<li>Feed the mice for 1 week on a regular diet first and let the mice adapt to the new environment of the animal center. After 1 week, provide a high-fat diet (diet composition: 20.0% lard, 10.0% sucrose, 2.5% cholesterol, 1.0% cholate, 66.5% conventional diet) for a period of 4 weeks.</li>
	<li>From the 1st day of the 5th week, intraperitoneally inject mice with streptozotocin solution at a dose of 35 mg/kg each day for 3 consecutive days. Prepare 1 mL of the streptozotocin solution with 10 mg of streptozotocin powder, with 0.1 M/L sodium citrate buffer as the solvent. 
	NOTE: The injection should be completed within 30 min after the solution is prepared, and the solution should be kept away from light during use.</li>
	<li>Randomly test blood glucose on day 5 and day 7 after the first injection of streptozotocin solution was administered. Animals with two random blood sugar levels higher than 16.7 mM/L are considered successful T2DM models.</li>
	<li>Begin training intervention on day 8 after the first injection of streptozotocin solution.</li>
</ol>
2. Grouping and treatment in mice
<ol>
	<li>Divide the T2DM mice into a model group, training group, and metformin group using the random number table method, with 6 mice in each group.</li>
	<li>Perform no intervention for the model group.</li>
	<li>Grind metformin tablets into powder and dissolve in pure water. Give metformin to the metformin group by gavage at a dose of 200 mg/kg, once per day, for 3 weeks.</li>
	<li>Let the training group do 30 min of static strength training, once a day, 5 days a week, for 3 weeks. Training is held every Monday to Friday afternoon.</li>
	<li>Randomly assign 6 non-T2DM mice as control group. These mice do not undergo modeling and intervention.</li>
</ol>
3. Manufacturing the static strength training device
<ol>
	<li>Prepare a 5 mm thick transparent acrylic board with dimensions of 20 cm x 20 cm. Use a transparent board in order to observe the mice training.</li>
	<li>Get wooden sticks with a diameter of 3 mm and a roll of tape with a width of 1 cm. Use a paper cutter to cut two 4 cm long sticks and four 1 cm long sticks.</li>
	<li>Attach two sticks, each with a length of 1 cm, to the ends of a stick with a length of 4 cm using tape (Figure 1A). The short sticks should be fixed on the same side as the long stick.</li>
	<li>Place the transparent board on a flat surface and attach two sets of 1 cm short sticks to the plate using a hot glue gun. Ensure the 4 cm wooden sticks do not come into contact with the board. Allow a 2 cm gap between the long stick and the board to hold the mice in place (Figure 1B). Let the two long sticks be aligned and parallel, with a distance of 6 cm between them (Figure 1C).</li>
</ol>
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/65556/65556fig01.jpg" /> 
Figure 1: Assemble and secure the sticks to the transparent board. (A) Tape the 1 cm stick to both ends of the 4 cm stick. (B) Use hot melt adhesive to connect the 1 cm long stick and transparent board, and the gap length is 2 cm. (C) Two 4 cm sticks spaced 6 cm apart. <a href="https://www.jove.com/files/ftp_upload/65556/65556fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
4. Static strength training in mice
<ol>
	<li>Cut two pieces of woolen yarn 15 cm long. Use a slipknot to tie a piece of woolen yarn on each of the mouse&#39;s upper ankle (Figure 2A). 
	NOTE: Elastic rope cannot fix the posture of mice, and hemp rope will wear the ankles of mice, so inelastic but soft woolen yarn is chosen here.</li>
	<li>Place the board horizontally on the table with sticks up. Press the mouse carefully between two long sticks, positioning its head and tail to align with the gaps below the sticks.</li>
	<li>Pass the yarn through the gap at the end of the tail. Then, adjust the yarn until the ankles of the mouse fit snugly against the edge of the stick.</li>
	<li>Secure the woolen yarn with tape (Figure 2B). The end of the woolen yarn should be secured otherwise, the mouse will climb the fallen wool. Pull the wool as tight as possible or the mouse will easily break free.</li>
	<li>Invert the transparent board. Get 2 boxes of the same height (15-20 cm tall) on either end of the transparent board. Place the board horizontally at a certain height. The box is located at either end of the mouse&#39;s head and tail. If it is too high, the experimenter will not be able to handle it easily; if it is too low, the mouse may touch the tabletop.</li>
	<li>Once the board is overturned, the mouse hangs upside down. Due to the righting reflex, mice curl their abdomen and extend their forelimbs to grasp their hindlimbs or sticks. At this stage, position a 20 cm stick in front of the mouse and carefully guide it to grasp the stick with its forelimbs. Repeat the process until the mouse becomes proficient at grasping the mobile stick.</li>
	<li>Use the stick to move the forelimb of the mouse to another 4 cm stick on the transparent board. Constantly adjust the angle of the stick to enable the mice to actively grasp the stationary 4 cm stick on the board (Figure 2C).</li>
	<li>Repeat the previous step as the mouse releases the front paw until the mouse is exhausted. After 30 minutes, most of the rats were unable to lift their upper body and grasp the stick with their forelimbs. 
	NOTE: Before implementing the intervention, a week of habituation training on mice is necessary. The initial training duration is 10 minutes per day, which should then be increased by 5 minutes each day until reaching a total of 30 minutes per day.</li>
	<li>After 30 min of training, immediately release the mouse and untangle the wool to prevent red and swollen feet caused by prolonged binding.
	<ol>
		<li>If skin lesions appear on the ankle of the mice after training, stop training the mice and seek veterinary professional care until the ankle is healthy.</li>
		<li>Some mice may occasionally manage to free themselves through intense struggle during training. The mice struggle when their hind legs were not firmly fixed. To avoid injury due to struggle, observe the mice throughout the training. When it is found that the hind limbs are not firmly fixed or the mice begin to struggle, loosen the mice and re-fix. 
		NOTE: Previous experiments have shown that hanging mice upside down for 30 min a day, 5 days a week, does not cause ankle wear, provided they are freed in due time10. Mice can learn and get used to the training in 1-3 sessions.</li>
	</ol>
	</li>
</ol>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/65556/65556fig02.jpg" /> 
Figure 2: Fixation method in mouse. (A) Tie the top of the ankle with a slipknot. (B) The end of the rope is passed through the gap and pulled tight, then secured with tape. (C) Static strength training in mice. <a href="https://www.jove.com/files/ftp_upload/65556/65556fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Exploring T2DM Exercise Interventions: A Static Training Device for Mice

<ol>
	<li>Zheng, Y., Ley, S. H., Hu, F. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+aetiology+and+epidemiology+of+type+2+diabetes+mellitus+and+its+complications.">Global aetiology and epidemiology of type 2 diabetes mellitus and its complications.</a> Nat Rev Endocrino. 14 (2), 88-98 (2018).</li><li>Li, X., 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=Effects+of+fitness+qigong+and+tai+chi+on+middle-aged+and+elderly+patients+with+type+2+diabetes+mellitus.">Effects of fitness qigong and tai chi on middle-aged and elderly patients with type 2 diabetes mellitus.</a> Public Lib Sci. 15 (12), e0243989 (2020).</li><li>Qin, 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=Effect+of+tai+chi+on+quality+of+life,+body+mass+index,+and+waist-hip+ratio+in+patients+with+type+2+diabetes+mellitus:+A+systematic+review+and+meta-analysis.">Effect of tai chi on quality of life, body mass index, and waist-hip ratio in patients with type 2 diabetes mellitus: A systematic review and meta-analysis.</a> Front Endocrino. 11, 543627 (2020).</li><li>Yang, H., Wu, X., Wang, M. <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+conventional+medical+treatment+plus+Qigong+exercise+on+type+2+diabetes+mellitus+in+Chinese+patients:+A+Meta-analysis.">Effect of conventional medical treatment plus Qigong exercise on type 2 diabetes mellitus in Chinese patients: A Meta-analysis.</a> J Trad Chinese Med. 38 (2), 167-174 (2018).</li><li>Yu, X., Chau, J. P. C., Huo, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effectiveness+of+traditional+Chinese+medicine-based+lifestyle+interventions+on+biomedical,+psychosocial,+and+behavioral+outcomes+in+individuals+with+type+2+diabetes:+A+systematic+review+with+meta-analysis.">The effectiveness of traditional Chinese medicine-based lifestyle interventions on biomedical, psychosocial, and behavioral outcomes in individuals with type 2 diabetes: A systematic review with meta-analysis.</a> Int J Nurs Stud. 80, 165-180 (2018).</li><li>A&#287;g&#246;n, E., 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=Effect+of+dynamic+and+static+strength+training+on+hormonal+activity+in+elite+boxers.">Effect of dynamic and static strength training on hormonal activity in elite boxers.</a> Baltic J Health Phys Activity. 12 (3), 1-10 (2020).</li><li>Merico, A., 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=Effects+of+combined+endurance+and+resistance+training+in+Amyotrophic+Lateral+Sclerosis:+A+pilot,+randomized,+controlled+study.">Effects of combined endurance and resistance training in Amyotrophic Lateral Sclerosis: A pilot, randomized, controlled study.</a> Eur J Translat Myo. 28 (1), 7278 (2018).</li><li>Liu, Y., 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=Eight+weeks+of+high-intensity+interval+static+strength+training+improves+skeletal+muscle+atrophy+and+motor+function+in+aged+rats+via+the+PGC-1&#945;/FNDC5/UCP1+pathway.">Eight weeks of high-intensity interval static strength training improves skeletal muscle atrophy and motor function in aged rats via the PGC-1&#945;/FNDC5/UCP1 pathway.</a> Clin Interven Aging. 16, 811-821 (2021).</li><li>Jun, X., 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=Animal+model+for+static+massage+training.">Animal model for static massage training.</a> Massage Guid. 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H., Park, S. Y., Choi, C. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insulin+resistance:+From+mechanisms+to+therapeutic+strategies.">Insulin resistance: From mechanisms to therapeutic strategies.</a> Diab Metab J. 46 (1), 15-37 (2022).</li><li>Campos, J. C., 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=Exercise+preserves+physical+fitness+during+aging+through+AMPK+and+mitochondrial+dynamics.">Exercise preserves physical fitness during aging through AMPK and mitochondrial dynamics.</a> Proc Natl Acad Sci U S A. 120 (2), e2204750120 (2023).</li></ol>

The authors declare that they have nothing to disclose.

Static strength training can reduce fat accumulation, aid weight loss, and increase metabolism8. In addition, it enhances the expression of PGC-1&#945; and mitochondrial biogenesis in skeletal muscle cells, leading to improved glucose metabolism in mice with type 2 diabetes mellitus and a consequent reduction in blood glucose levels11. To confirm the impact and mechanism of static training on T2DM, appropriate devices need to be developed for performing static training on e...

Type 2 diabetes mellitus (T2DM) is a chronic disease characterized by insulin resistance and &#946;-cell dysfunction that is a significant threat to global health1. Exercise is a crucial intervention in the management of type 2 diabetes. Numerous studies have shown that traditional Chinese exercise methods, such as Tai Chi and Ba Duan Jin, significantly improve blood glucose levels and quality of life for individuals with T2DM2,3,4,5. To execute these movements, the trainer must maintain a stable body and joint position for a period of time. The static position is sustained by performing static muscle contractions, which is commonly referred to as static strength6.
However, the mechanism of static strength training intervention in T2DM has not been clarified. To answer this question, animal experiments are essential. During isometric exercises, muscles are activated, maintain a constant length, and safely achieve maximum tension7. In experiments with static strength training, the test animal is required to perform isometric muscle contractions and to maintain this state of muscular contraction. How to implement static strength training on mice, rats, and other laboratory animals has become a big problem in research. First, animals struggle to obey commands and contract their muscles as required. Secondly, it is difficult for the animal to maintain a stable position under resistance, and the purpose of isometric muscle contraction cannot be achieved. While letting animals train as required, it is important to address concerns related to animal welfare, such as relieving stress and anxiety, minimizing pain, and improving overall conditions. This protocol pertains to a static training model for rats8,9, and here we introduce a simple device for static training of mice. When the hind legs of mice are lifted, their abdominal muscles contract due to the righting reflex, the forepaws grasp the cross-bar in front, and then the front and back limbs contract against gravity. The mice cannot move after grasping the short bar, resulting in their muscles being in a state of isometric contraction.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Acrylic boards</td>
			<td></td>
			<td></td>
			<td>Transparent acrylic boards with 5mm thickness. The size should be larger than 20cm&#215;20cm</td>
		</tr>
		<tr>
			<td>Boxes</td>
			<td></td>
			<td></td>
			<td>Two boxes of the same height (15~20cm)</td>
		</tr>
		<tr>
			<td>ELISA KIT</td>
			<td></td>
			<td>H203-1-2</td>
			<td>Nanjing Jiancheng Bioengineering Institute</td>
		</tr>
		<tr>
			<td>Hot melt glue gun</td>
			<td></td>
			<td></td>
			<td>Avoid touching the gun head to cause burns</td>
		</tr>
		<tr>
			<td>Knives</td>
			<td></td>
			<td></td>
			<td>No special requirement</td>
		</tr>
		<tr>
			<td>Metformin tablets</td>
			<td></td>
			<td>1396309</td>
			<td>Sigma</td>
		</tr>
		<tr>
			<td>scissors</td>
			<td></td>
			<td></td>
			<td>No special requirement</td>
		</tr>
		<tr>
			<td>Sticks</td>
			<td></td>
			<td></td>
			<td>Several wooden sticks with a diameter of 3mm</td>
		</tr>
		<tr>
			<td>Streptozotocin</td>
			<td></td>
			<td>S0130</td>
			<td>Sigma</td>
		</tr>
		<tr>
			<td>Tape</td>
			<td></td>
			<td></td>
			<td>No special requirement</td>
		</tr>
		<tr>
			<td>Transmission Electron Microscope (TEM)</td>
			<td></td>
			<td>HT7700</td>
			<td>HITACHI&#160;</td>
		</tr>
	</tbody>
</table>

static strength training method for type 2 diabetic mice

The treatment of type 2 diabetes mellitus (T2DM) is a major difficulty in improving patient health. Exercise is one of the main interventions for T2DM. Static strength training is one of the key forms of traditional sports in China. Research shows that static strength training is an effective clinical method for T2DM intervention, but there is no experimental device suitable for static training in mice. One of the difficulties in moving from clinical to basic research is to design appropriate experimental devices. In order to further study the mechanism of static training intervention in T2DM, a simple method for making a static training device for mice is introduced in this paper. This device has the advantages of simple operation, cheap material, and high feasibility. Previous studies conducted under this protocol have shown that static training can effectively reduce blood glucose levels and improve the mitochondrial function of skeletal muscle cells in T2DM mice. The purpose of introducing this device is to promote research on the mechanism of traditional exercise in the intervention of T2DM and to lay a foundation for the quantitative intervention of exercise.

Following the above protocol, the hind limbs of the mouse are fixed, and the forelimbs autonomously grasp the front bar. The narrow range of motion keeps the mouse in a relatively fixed position. The muscles of mice can be confirmed to contract by touching the muscles of their abdomen and legs. This is consistent with the need for the state of isometric muscle contraction in static strength training. Training mice according to the protocol, with the increase in training times, will help the mice adapt to the training whi...

Watch this Scientific Journal Video about Author Spotlight: Advancing Diabetes Research with Static Exercise Training in Mice at JoVE.com

Author Spotlight: Advancing Diabetes Research with Static Exercise Training in Mice

This protocol provides a simple method of making static training equipment for mice. The device maintains the muscle isometric contraction of the limbs of mice so as to verify the intervention effect of traditional exercise on type 2 diabetes (T2DM) and provides new exercise therapy for the clinical treatment of T2DM.

Static Strength Training Method for Type 2 Diabetic Mice

The treatment of type 2 diabetes mellitus (T2DM) is a major difficulty in improving patient health. Exercise is one of the main interventions for T2DM. ...

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400 Views.  Nanjing University of Chinese Medicine. This protocol provides a simple method of making static training equipment for mice. The device maintains the muscle isometric contraction of the limbs of mice so as to verify the intervention effect of traditional exercise on type 2 diabetes (T2DM) and provides new exercise therapy for the clinical treatment of T2DM.

Video: Author Spotlight: Advancing Diabetes Research with Static Exercise Training in Mice

Measuring the Strength of Mice

Kondziela7 devised the inverted screen test and published it in 1964. It is a test of muscle strength using all four limbs. Most normal mice easily score maximum on this task; it is a quick but insensitive gross screen, and the weights test described in this article will provide a finer measure of muscular strength.
There are also several strain gauge-based pieces of apparatus available commercially that will provide more graded data than the inverted screen test, but their cost may put them beyond the reach of many laboratories which do not specialize in strength testing. Hence in 2000 a cheap and simple apparatus was devised by the author. It consists of a series of chain links of increasing length, attached to a "fur collector" a ball of fine wire mesh sold for preventing limescale build up in hard water areas. An accidental observation revealed that mice could grip these very tightly, so they proved ideal as a grip point for a weight-lifting apparatus. A common fault with commercial strength meters is that the bar or other grip feature is not thin enough for mice to exert a maximum grip. As a general rule, the thinner the wire or bar, the better a mouse can grip with its small claws.
This is a pure test of strength, although as for any test motivational factors could potentially play a role. The use of scale collectors, however, seems to minimize motivational problems as the motivation appears to be very high for most normal young adult mice.

Deficits in muscular strength occur in many clinical conditions such as motor neuron disease. The inverted screen and weight lifting tests described here measure strength in mice almost exclusively, with minimal influence of factors such as coordination.

Kondziela7 devised the inverted screen test and published it in 1964. It is a test of muscle strength using all four limbs. Most normal mice easily score ...

Neo-Islet Formation in Liver of Diabetic Mice by Helper-dependent Adenoviral Vector-Mediated Gene Transfer

Type 1 diabetes is caused by T cell-mediated autoimmune destruction of insulin-producing cells in the pancreas. Until now insulin replacement is still the major therapy, because islet transplantation has been limited by donor availability and by the need for long-term immunosuppression. Induced islet neogenesis by gene transfer of Neuogenin3 (Ngn3), the islet lineage-defining specific transcription factor and Betacellulin (Btc), an islet growth factor has the potential to cure type 1 diabetes.
Adenoviral vectors (Ads) are highly efficient gene transfer vector; however, early generation Ads have several disadvantages for in vivo use. Helper-dependent Ads (HDAds) are the most advanced Ads that were developed to improve the safety profile of early generation of Ads and to prolong transgene expression1. They lack chronic toxicity because they lack viral coding sequences2-5 and retain only Ad cis elements necessary for vector replication and packaging. This allows cloning of up to 36 kb genes.
In this protocol, we describe the method to generate HDAd-Ngn3 and HDAd-Btc and to deliver these vectors into STZ-induced diabetic mice. Our results show that co-injection of HDAd-Ngn3 and HDAd-Btc induces 'neo islets' in the liver and reverses hyperglycemia in diabetic mice.

We describe hepatic neo-islet formation in STZ (streptozotocin)-induced diabetic mice by gene transfer of Neurogenin3 (Ngn3) and Betacellulin (Btc) using helper-dependent adenoviral vector (HDAd) and the reversal of hyperglycemia. Our method takes advantages of helper-dependent adenoviral vectors with their highly efficient in vivo transduction and the long lasting gene expression.

Type 1 diabetes is caused by T cell-mediated autoimmune destruction of insulin-producing cells in the pancreas. Until now insulin replacement is still the ...

Assessment of Gastric Emptying in Non-obese Diabetic Mice Using a [13C]-octanoic Acid Breath Test

Gastric emptying studies in mice have been limited by the inability to follow gastric emptying changes in the same animal since the most commonly used techniques require killing of the animals and postmortem recovery of the meal1,2. This approach prevents longitudinal studies to determine changes in gastric emptying with age and progression of disease. The commonly used [13C]-octanoic acid breath test for humans3 has been modified for use in mice4-6 and rats7 and we previously showed that this test is reliable and responsive to changes in gastric emptying in response to drugs and during diabetic disease progression8. In this video presentation the principle and practical implementation of this modified test is explained. As in the previous study, NOD LtJ mice are used, a model of type 1 diabetes9. A proportion of these mice develop the symptoms of gastroparesis, a complication of diabetes characterized by delayed gastric emptying without mechanical obstruction of the stomach10.
This paper demonstrates how to train the mice for testing, how to prepare the test meal and obtain 4 hr gastric emptying data and how to analyze the obtained data. The carbon isotope analyzer used in the present study is suitable for the automatic sampling of the air samples from up to 12 mice at the same time. This technique allows the longitudinal follow-up of gastric emptying from larger groups of mice with diabetes or other long-standing diseases.

Assessment of Gastric Emptying in Non-obese Diabetic Mice Using a [13C]-octanoic Acid Breath Test

Determination of gastric emptying with a non-invasive [13C]-octanoic acid breath test for tracking gastroparesis in female NOD LtJ mice.

Gastric emptying studies in mice have been limited by the inability to follow gastric emptying changes in the same animal since the most commonly used ...

Step By Step: Microsurgical training method combining two nonliving animal models

The learning of microsurgical techniques and the maintenance of microsurgical skills have been traditionally based on the use of living animals, mainly laboratory rats. This method although extremely valuable can be economically demanding both for the surgeon and the sponsoring institution; it also requires special training facilities that may not always be available or accessible. Furthermore ethical concerns can limit the use of living animals for training purposes. Alternative training methods, such as inert tubes and gloves have not gained popularity among surgeons since they do not offer an experience similar to that of a clinical situation. Non-living animal models include the use of chicken thighs and wings; they offer a practice experience that resembles a clinical situation to a considerable extent. This type of training is relatively cheap and easily available. The microscope and instruments required can be acquired over the internet, and the chicken pieces can be bought at the local supermarket.
This approach allows a motivated trainee to rehearse different types of surgical techniques several times at a reasonable expense, helping to develop or maintain his surgical expertise if more complex facilities are not available. On the current manuscript we describe how to setup a small practice station, how to dissect the specimens, and how to practice both with the chicken thighs and with the chicken wings in a progressive fashion. This approach takes advantage on the versatility of the chicken thigh model and the small size of the chicken wing Brachial artery.

Here we describe how to set up a small microsurgical practice station and a simple and inexpensive method for the training of microsurgery with non-living animal models.

The learning of microsurgical techniques and the maintenance of microsurgical skills have been traditionally based on the use of living animals, mainly ...

Leprdb Mouse Model of Type 2 Diabetes: Pancreatic Islet Isolation and Live-cell 2-Photon Imaging Of Intact Islets

Type 2 diabetes is a chronic disease affecting 382 million people in 2013, and is expected to rise to 592 million by 2035 1. During the past 2 decades, the role of beta-cell dysfunction in type 2 diabetes has been clearly established 2. Research progress has required methods for the isolation of pancreatic islets. The protocol of the islet isolation presented here shares many common steps with protocols from other groups, with some modifications to improve the yield and quality of isolated islets from both the wild type and diabetic Leprdb (db/db) mice. A live-cell 2-photon imaging method is then presented that can be used to investigate the control of insulin secretion within islets.

Leprdb Mouse Model of Type 2 Diabetes: Pancreatic Islet Isolation and Live-cell 2-Photon Imaging Of Intact Islets

We present here a protocol for the isolation of islets from the mouse model of type 2 diabetes, Leprdb and details of a live-cell assay for measurement of insulin secretion from intact islets that utilizes 2 photon microscopy.

Type 2 diabetes is a chronic disease affecting 382 million people in 2013, and is expected to rise to 592 million by 2035 1. During the past 2 decades, ...

Adapted Resistance Training Improves Strength in Eight Weeks in Individuals with Multiple Sclerosis

Hip weakness is a common symptom affecting walking ability in people with multiple sclerosis (MS). It is known that resistance strength training (RST) can improve strength in individuals with MS, however; it remains unclear the duration of RST that is needed to make strength gains and how to adapt hip strengthening exercises for individuals of varying strength using only resistance bands. This paper describes the methodology to set up and implement an adapted resistance strength training program, using resistance bands, for individuals with MS. Directions for pre- and post-strength tests to evaluate efficacy of the strength-training program are included. Safety features and detailed instructions outline the weekly program content and progression. Current evidence is presented showing that significant strength gains can be made within 8 weeks of starting a RST program. Evidence is also presented showing that resistance strength training can be successfully adapted for individuals with MS of varying strength with little equipment.

Hip weakness is a common symptom affecting walking ability in people with multiple sclerosis. Isolated muscle strengthening is a useful method to target specific weaknesses. This protocol describes a progressive resistance-training program using exercise bands to increase hip muscle strength.

Hip weakness is a common symptom affecting walking ability in people with multiple sclerosis (MS). It is known that resistance strength training (RST) can ...

Improving Strength, Power, Muscle Aerobic Capacity, and Glucose Tolerance through Short-term Progressive Strength Training Among Elderly People

This protocol describes the simultaneous use of a broad span of methods to examine muscle aerobic capacity, glucose tolerance, strength, and power in elderly people performing short-term resistance training (RET). Supervised progressive resistance training for 1 h three times a week over 8 weeks was performed by RET participants (71&#177;1 years, range 65-80). Compared to a control group without training, the RET showed improvements on the measures used to indicate strength, power, glucose tolerance, and several parameters of muscle aerobic capacity. Strength training was performed in a gym with only robust fitness equipment. An isokinetic dynamometer for knee extensor strength permitted the measurement of concentric, eccentric, and static strength, which increased for the RET group (8-12% post- versus pre-test). The power (rate of force development, RFD) at the initial 0-30 ms also showed an increase for the RET group (52%). A glucose tolerance test with frequent blood glucose measurements showed improvements only for the RET group in terms of blood glucose values after 2 h (14%) and the area under the curve (21%). The blood lipid profile also improved (8%). From muscle biopsy samples prepared using histochemistry, the amount of fiber type IIa increased, and a trend towards a decrease in IIx in the RET group reflected a change to a more oxidative profile in terms of fiber composition. Western blot (to determine the protein content related to the signaling for muscle protein synthesis) showed a rise of 69% in both Akt and mTOR in the RET group; this also showed an increase in mitochondrial proteins for OXPHOS complex II and citrate synthase (both ~30%) and for complex IV (90%), in only the RET group. We demonstrate that this type of progressive resistance training offers various improvements (e.g., strength, power, aerobic capacity, glucose tolerance, and plasma lipid profile).

The effect of short-term resistance training on elderly people was investigated through the simultaneous use of several methods. Compared to a control group, many improvements were seen, including on muscle aerobic capacity, glucose tolerance, strength, power, and muscle quality (i.e., protein involved in cell signaling and muscle fiber type composition).

This protocol describes the simultaneous use of a broad span of methods to examine muscle aerobic capacity, glucose tolerance, strength, and power in ...

A Closed-chest Model to Induce Transverse Aortic Constriction in Mice

Research on cardiac hypertrophy and heart failure is frequently based on pressure overload mouse models induced by TAC. The standard procedure is to perform a partial thoracotomy to visualize the transverse aortic arch. However, the surgical trauma caused by the thoracotomy in open-chest models changes the respiratory physiology as the ribs are dissected and left unattached after chest closure. To prevent this, we established a minimally invasive, closed chest approach via lateral thoracotomy. Herein we approach the aortic arch via the 2nd intercostal space without entering the chest cavities, leaving the mouse with a less traumatic injury to recover from. We perform this operation using standard laboratory settings for open chest TAC procedures with equal survival rates. Apart from maintaining physiological breathing patterns due to the closed chest approach, the mice seem to benefit by showing rapid recovery, as the less invasive technique appears to facilitate a fast healing process and to reduce immune response after trauma.

Here, we present a protocol of Transverse Aortic constriction (TAC) via a lateral thoracotomy. This technique is a minimally invasive, closed chest surgical procedure aiming to simulate pressure overload and heart failure in mice utilizing standard TAC laboratory settings.

Research on cardiac hypertrophy and heart failure is frequently based on pressure overload mouse models induced by TAC. The standard procedure is to ...

Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations

Many hamstring injuries that occur during physical activity occur while the muscles are lengthening, during eccentric hamstring muscle actions. Opposite of these eccentric hamstring actions are concentric quadriceps actions, where the larger and likely stronger quadriceps straighten the knee. Therefore, to stabilize the lower limbs during movement, the hamstrings must eccentrically combat against the strong knee-straightening torque of the quadriceps. As such, eccentric hamstring strength expressed relative to concentric quadricep strength is commonly referred to as the &#34;functional ratio&#34; as most movements in sports require simultaneous concentric knee extension and eccentric knee flexion. To increase the strength, resiliency, and functional performance of the hamstrings, it is necessary to test and train the hamstrings at different eccentric speeds. The main purpose of this work is to provide instructions for measuring and interpreting eccentric hamstring strength. Techniques for measuring the functional ratio using isokinetic dynamometry are provided and sample data will be compared. Additionally, we briefly describe how to address hamstring strength deficiencies or unilateral strength differences using exercises that specifically focus on increasing eccentric hamstring strength.

The hamstrings are a group of muscles that are sometimes problematic for athletes, resulting in soft tissue injury in the lower limbs. To prevent such injuries, functional training of the hamstrings requires intensive eccentric contractions. Additionally, hamstring function should be tested in relation to quadricep function at different contraction speeds.

Many hamstring injuries that occur during physical activity occur while the muscles are lengthening, during eccentric hamstring muscle actions. Opposite ...

Protocol to Create Chronic Wounds in Diabetic Mice

Chronic wounds develop as a result of defective regulation in one or more complex cellular and molecular processes involved in proper healing. They impact ~6.5M people and cost ~$40B/year in the US alone. Although a significant effort has been invested in understanding how chronic wounds develop in humans, fundamental questions remain unanswered. Recently, we developed a novel mouse model for diabetic chronic wounds that have many characteristics of human chronic wounds. Using db/db-/- mice, we can generate chronic wounds by inducing high levels of oxidative stress (OS) in the wound tissue immediately after wounding, using a one-time treatment with inhibitors specific to the antioxidant enzymes catalase and glutathione peroxidase. These wounds have high levels of OS, develop biofilm naturally, become fully chronic within 20 days after treatment and can remain open more for more than 60 days. This novel model has many features of diabetic chronic wounds in humans and therefore can contribute significantly to advancing fundamental understanding of how wounds become chronic. This is a major breakthrough because chronic wounds in humans cause significant pain and distress to patients and result in amputation if unresolved. Moreover, these wounds are very expensive and time-consuming to treat, and lead to significant loss of personal income to patients. Advancements in this field of study through the use of our chronic wound model can significantly improve health care for millions who suffer under this debilitating condition. In this protocol, we describe in great detail the procedure to cause acute wounds to become chronic, which has not been done before.

Chronic wounds are developed from acute wounds on a diabetic mouse model by inducing high levels of oxidative stress after a full-thickness cutaneous wound. The wound is treated with inhibitors for catalase and glutathione peroxidase, resulting in impaired healing and biofilm development by bacteria present in the skin microbiome.

Chronic wounds develop as a result of defective regulation in one or more complex cellular and molecular processes involved in proper healing. They impact ...