Name: extraction and analysis of cortisol from human and monkey hair
Uploaded: 2014-01-24T08:45:00
Description: Watch this Scientific Journal Video about Extraction and Analysis of Cortisol from Human and Monkey Hair at JoVE.com

We thank Kymberlee O&#39;Brien, Celia Moore, and Edward Tronick (Department of Psychology, University of Massachusetts,&#160;Boston) for providing the human hair samples analyzed in this study, and Stephen Suomi and Amanda Dettmer (Laboratory of Comparative Ethology, NICHD) for providing the rhesus monkey hair samples. Initial development and continued use of this method has been supported by NIH RR11122 to M.A.N.

1. Sample Collection and Storage
<ol>
	<li>Human hair
	<ol>
		<li>Secure the entire length of the hair to be sampled (up to a pencil-width in diameter) with a rubber band or clip. Cut hair as close to the scalp as possible (taking care not to nick the skin) with a clean scissors. Note: The standard sampling area is the posterior vertex of the skull.</li>
		<li>Some investigators have reported a decline in human hair CORT levels&#160; with distance from the scalp6, which may be due to washout from repeated ex...

<ol>
	<li>Selye, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stress+and+the+general+adaptation+syndrome.">Stress and the general adaptation syndrome.</a> Br. Med. J. 1 (4667), 1383-1392 (1950).</li><li>Meyer, J. S., Novak, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Minireview:+Hair+cortisol:+A+novel+biomarker+of+hypothalamic-+pituitary-adrenocortical+activity.">Minireview: Hair cortisol: A novel biomarker of hypothalamic- pituitary-adrenocortical activity.</a> Endocrinology. 153, 4120-4127 (2012).</li><li>Tiefenbacher, S., Novak, M. A., Lutz, C. K., Meyer, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+physiology+and+neurochemistry+of+self-injurious+behavior:+A+nonhuman+primate+model.">The physiology and neurochemistry of self-injurious behavior: A nonhuman primate model.</a> Front. Biosci. 10, 1-11 (2005).</li><li>Davenport, M. D., Tiefenbacher, S., Lutz, C. K., Novak, M. A., Meyer, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+endogenous+cortisol+concentrations+in+the+hair+of+rhesus+macaques.">Analysis of endogenous cortisol concentrations in the hair of rhesus macaques.</a> Gen. Comp. Endocrinol. 147, 255-261 (2006).</li><li>Davenport, M. D., Lutz, C. K., Tiefenbacher, S., Novak, M. A., Meyer, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+rhesus+monkey+model+of+self+injury:+Effects+of+relocation+stress+on+behavior+and+neuroendocrine+function.">A rhesus monkey model of self injury: Effects of relocation stress on behavior and neuroendocrine function.</a> Biol. Psychiatry. 63, 990-996 (2008).</li><li>Kirschbaum, C., Tietze, A., Skoluda, N., Dettenborn, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hair+as+a+retrospective+calendar+of+cortisol+production+-+Increased+cortisol+incorporation+into+hair+in+the+third+trimester+of+pregnancy.">Hair as a retrospective calendar of cortisol production - Increased cortisol incorporation into hair in the third trimester of pregnancy.</a> Psychoneuroendocrinology. 34, 32-37 (2009).</li><li>Hamel, A. F., Meyer, J. S., Henchey, E., Dettmer, A. M., Suomi, S. J., Novak, M. A. <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+shampoo+and+water+washing+on+hair+cortisol+concentrations.">Effects of shampoo and water washing on hair cortisol concentrations.</a> Clin. Chim. Acta. 412, 382-385 (2011).</li><li>Manenschijn, L., Koper, J. W., Lamberts, S. W., van Rossum, E. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+a+method+to+measure+long+term+cortisol+levels.">Evaluation of a method to measure long term cortisol levels.</a> Steroids. 76, 1032-1036 (2011).</li><li>Thomson, S., Koren, G., Fraser, L. A., Rieder, M., Friedman, T. C., Van Uum, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hair+analysis+provides+a+historical+record+of+cortisol+levels+in+Cushing&#8217;s+syndrome.">Hair analysis provides a historical record of cortisol levels in Cushing&#8217;s syndrome.</a> Exp. Clin. Endocrinol. Diabetes. 118, 133-138 (2010).</li><li>LeBeau, M. A., Montgomery, M. A., Brewer, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+variations+in+growth+rate+and+sample+collection+on+interpreting+results+of+segmental+analyses+of+hair.">The role of variations in growth rate and sample collection on interpreting results of segmental analyses of hair.</a> Forensic Sci. Int. 210, 110-116 (2011).</li><li>Dolnick, E. H., Montagna, W., Dobson, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Variability+of+hair+growth+in+Macaca+mulatta.">Variability of hair growth in Macaca mulatta.</a> Adv. Biol. Skin. IX, 121-128 (1969).</li><li>Sauv&#233;, B., Koren, G., Walsh, G., Uum Tokmakejian, S. V. a. n., H, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+cortisol+in+human+hair+as+a+biomarker+of+systemic+exposure.">Measurement of cortisol in human hair as a biomarker of systemic exposure.</a> Clin. Invest. Med. 30, 183-191 (2007).</li><li>Gow, R., Thomson, S., Rieder, M., Van Uum, S., Koren, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+assessment+of+cortisol+analysis+in+hair+and+its+clinical+applications.">An assessment of cortisol analysis in hair and its clinical applications.</a> Forensic Sci. Int. 196, 32-37 (2010).</li><li>Bechsh&#248;ft, T. &. #. 2. 1. 6. ;., Sonne, C., Dietz, R., Born, E. W., Novak, M. A., Henchey, E., Meyer, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cortisol+levels+in+hair+of+East+Greenland+polar+bears.">Cortisol levels in hair of East Greenland polar bears.</a> Sci. Total Environ. 409, 831-834 (2011).</li><li>Cooper, G. A. A., Kronstrand, R., Kintz, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Society+of+Hair+Testing+guidelines+for+drug+testing+in+hair.">Society of Hair Testing guidelines for drug testing in hair.</a> Forensic Sci. Int. 218, 20-28 (2012).</li><li>Ito, N., Ito, T., Kromminga, A., Bettermann, A., Takigawa, M., Kees, F., Straub, R. H., Paus, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+hair+follicles+display+a+functional+equivalent+of+the+hypothalamic-pituitary-adrenal+(HPA)+axis+and+synthesize+cortisol.">Human hair follicles display a functional equivalent of the hypothalamic-pituitary-adrenal (HPA) axis and synthesize cortisol.</a> FASEB J. 19, 1332-1334 (2005).</li><li>Russell, E., Koren, G., Rieder, M., Van Uum, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hair+cortisol+as+a+biological+marker+of+chronic+stress:+Current+status,+future+directions+and+unanswered+questions.">Hair cortisol as a biological marker of chronic stress: Current status, future directions and unanswered questions.</a> Psychoneuroendocrinology. 37, 589-601 (2012).</li><li>Stalder, T., Kirschbaum, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+cortisol+in+hair+-+State+of+the+art+and+future+directions.">Analysis of cortisol in hair - State of the art and future directions.</a> Brain Behav. Immun. 26, 1019-1029 (2012).</li><li>Staufenbiel, S. M., Penninx, B. W., Spijker, A. T., Elzinga, B. M., van Rossum, E. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hair+cortisol,+stress+exposure,+and+mental+health+in+humans:+A+systematic+review.">Hair cortisol, stress exposure, and mental health in humans: A systematic review.</a> Psychoneuroendocrinology. 38, 1220-1235 (2013).</li></ol>

The hair CORT procedure described above is simple to perform, is relatively inexpensive, makes use of readily available chemicals, reagents, and supplies, and requires equipment that, with one exception, is likely to be present in a typical analytical laboratory. The exception is a grinding apparatus such as a ball mill or mini-beadbeater. We note that some research groups mince hair samples into small fragments roughly 1&#160;mm in length12, but based on our observations we recommend performing grinding inste...

Measurement of CORT in plasma, saliva, or occasionally in urine or feces has been used as an index of physiological stress since Selye&#39;s discovery of the role of the HPA axis in stress1. Although numerous papers have been published relating HPA activity to acutely stressful situations, the field has been hampered by the lack of a simple and reliable index of chronic physiological stress. This problem arises because plasma and saliva both yield &#34;point&#34; estimates of HPA activity that are subject to circadian variation and can be confounded by environmental disturbances. Urinary and fecal samples yield measurements of CORT and/or metabolite excretion that span a number of hours up to a full day in some cases. Collection of multiple samples using any of these matrices may provide a rough composite index of CORT levels over time; however, none of these approaches provides a truly long-term index of HPA activity and the responsiveness of this system to chronic stressors.
Measuring CORT in hair has begun to fill this important need in the stress literature. Initial studies by several laboratories demonstrated the presence of CORT in human hair but did not investigate whether hair CORT levels changed as a function of stress2. As our laboratory has been interested for many years in the regulation of the rhesus monkey HPA axis by various social and behavioral factors3, we set out to establish and validate methods for extraction and analysis of rhesus monkey hair4. Based on the premise that blood-borne CORT is slowly and continuously incorporated into growing hair, the purpose of this new method was to use levels of hair-derived CORT as an integrated index of HPA activity over periods of weeks to months.
Several methodological challenges were encountered in developing the present protocol. First, previous studies had shown that small amounts of circulating CORT are excreted in sweat and sebum and therefore could coat the outside of the hair shaft2. In order to eliminate this potential confound, we developed a mild wash procedure that appears to remove external CORT while having a minimal effect on CORT present within the growing hair shaft. Thus, monkey hair subjected to this procedure (i.e.&#160;two 3-min washes with isopropanol) lost approximately 7-8% of the total hair CORT content, and a third wash removed less than 1% more steroid from the sample4. There appears to be more external CORT in human hair, since the same procedure removed an average of 27% total CORT content from the samples (K. Rosenberg and J. Meyer, unpublished). Like monkey hair, however, an additional wash contained much less CORT (about 7%) than the first two washes. Therefore, results from both monkey and human hair support the contention that most (if not all) external CORT can be removed while maintaining a major fraction of CORT within the internal hair matrix. Second, our pilot studies also showed that grinding the hair prior to extraction significantly increased CORT recovery from the sample, presumably by breaking open the complex proteinaceous matrix of the hair shaft as well as increasing the surface area available for solvent penetration. Two different grinding methods were developed, each with advantages and disadvantages. Method 1, which uses a ball mill, has the advantage of producing the finest powder. However, a ball mill is a relatively expensive equipment item and, if used with standard grinding jars and balls, it is capable of grinding only two samples at a time. Small samples are also difficult to process using a ball mill with standard grinding jars. Method 2, which uses a beadbeater, is less effective in its grinding ability. As a result, average CORT recovery is approximately 10% lower using this method compared to the ball mill (unpublished data). On the other hand, a beadbeater is considerably less expensive than a ball mill, 16-24 samples can be ground at once depending on the model, and the method is well suited for small samples. Because of the above mentioned differential recovery, it is advisable to use the same grinding method for all samples within a particular study.
Once the hair samples have been processed, they are extracted with methanol and CORT in the extracts is analyzed by means of a sensitive and specific commercial EIA kit originally designed to measure salivary CORT. The extraction and assay procedures were validated in part by demonstrating that serial dilutions of extracts from monkey hair samples yielded EIA readings that closely paralleled the readings obtained from authentic CORT standards. We then showed that hair CORT (in addition to plasma and salivary CORT) was sensitive to the major life stressor of an administratively mandated relocation of the monkeys to new housing quarters4,5. The present paper provides a detailed account of the methods used routinely in our laboratory to process human and monkey hair samples and to extract and analyze CORT from such samples.

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	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">HPLC-grade isopropanol</td>
			<td style="width:116px;">Fisher</td>
			<td style="width:119px;">A451</td>
			<td style="width:247px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">HPLC-grade methanol</td>
			<td style="width:116px;">Fisher</td>
			<td style="width:119px;">A452</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">Salivary cortisol assay kits</td>
			<td style="width:116px;">Salimetrics</td>
			<td style="width:119px;">1-3002</td>
			<td>See manufacturer&#39;s kit insert for information on assay sensitivity and specificity</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">15-ml polypropylene screw-cap centrifuge tubes</td>
			<td style="width:116px;">Max Scientific</td>
			<td>10-9151</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">1.5-ml Safe-Lock microcentrifuge tubes</td>
			<td style="width:116px;">Fisher</td>
			<td style="width:119px;">05-402-25</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">2.0-ml Safe-Lock microcentrifuge tubes</td>
			<td style="width:116px;">Fisher</td>
			<td style="width:119px;">05-402-7</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2.0-ml XXTuff reinforced microvials</td>
			<td style="width:116px;">BioSpec</td>
			<td>330TX</td>
			<td>Use with mini-beadbeater</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">3.2-mm chrome-steel beads</td>
			<td style="width:116px;">BioSpec</td>
			<td>11079132c</td>
			<td>Use with mini-beadbeater</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">10-ml stainless steel grinding jars</td>
			<td style="width:116px;">Retsch</td>
			<td style="width:119px;">02.462.0061</td>
			<td>Use with mixer mill</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">12-mm stainless steel grinding balls</td>
			<td style="width:116px;">Retsch</td>
			<td style="width:119px;">05.368.0037</td>
			<td>Use with mixer mill</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Savant activated carbon cartridge</td>
			<td style="width:116px;">Fisher</td>
			<td>DTK120R</td>
			<td>Use with Savant chemical trap</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;"></td>
			<td style="width:116px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;"></td>
			<td style="width:116px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">Name of Equipment</td>
			<td style="width:116px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td>Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">Rotator for 15-ml centrifuge tubes</td>
			<td style="width:116px;">Fisher</td>
			<td>S02135</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">Rotator for microcentrifuge tubes</td>
			<td style="width:116px;">Fisher</td>
			<td>NC9854190&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Benchtop centrifuge for microcentrifuge tubes</td>
			<td style="width:116px;">Fisher</td>
			<td>13-100-675</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">MM 200 mixer mill</td>
			<td style="width:116px;">Retsch</td>
			<td style="width:119px;">20.746.0001</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Mini-Beadbeater 16&#160;</td>
			<td style="width:116px;">BioSpec</td>
			<td>607</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Savant DNA Speedvac</td>
			<td style="width:116px;">Fisher</td>
			<td>DNA120-115</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Savant refrigerated vapor trap</td>
			<td style="width:116px;">Fisher</td>
			<td>RVT400-115</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Savant chemical trap</td>
			<td style="width:116px;">Fisher</td>
			<td>SCT120</td>
			<td>Alternative to refrigerated vapor trap</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Microplate reader</td>
			<td style="width:116px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Microplate washer</td>
			<td style="width:116px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Microplate mixer</td>
			<td style="width:116px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:316px;">Multichannel pipetter</td>
			<td style="width:116px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Analytical balance</td>
			<td style="width:116px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

extraction and analysis of cortisol from human and monkey hair

The stress hormone cortisol (CORT) is slowly incorporated into the growing hair shaft of humans, nonhuman primates, and other mammals. We developed and validated a method for CORT extraction and analysis from rhesus monkey hair and subsequently adapted this method for use with human scalp hair. In contrast to CORT &#34;point samples&#34; obtained from plasma or saliva, hair CORT provides an integrated measure of hypothalamic-pituitary-adrenocortical (HPA) system activity, and thus physiological stress, during the period of hormone incorporation. Because human scalp hair grows at an average rate of 1 cm/month, CORT levels obtained from hair segments several cm in length can potentially serve as a biomarker of stress experienced over a number of months.
In our method, each hair sample is first washed twice in isopropanol to remove any CORT from the outside of the hair shaft that has been deposited from sweat or sebum. After drying, the sample is ground to a fine powder to break up the hair&#39;s protein matrix and increase the surface area for extraction. CORT from the interior of the hair shaft is extracted into methanol, the methanol is evaporated, and the extract is reconstituted in assay buffer. Extracted CORT, along with standards and quality controls, is then analyzed by means of a sensitive and specific commercially available enzyme immunoassay (EIA) kit. Readout from the EIA is converted to pg CORT per mg powdered hair weight. This method has been used in our laboratory to analyze hair CORT in humans, several species of macaque monkeys, marmosets, dogs, and polar bears. Many studies both from our lab and from other research groups have demonstrated the broad applicability of hair CORT for assessing chronic stress exposure in natural as well as laboratory settings.

Figure 1&#160;shows the printout from a representative set of human hair samples (adult male and female human subjects) processed using method 2 grinding and extraction. Computer software was used to generate the data output and to fit a 4-parameter sigmoidal curve to the CORT standards (Figure 2). The between-well CVs from this plate ranged from 0.01-5.73% with an average intra-assay CV of 1.34%. The inter-assay CV determined using the QC values from nine recent human hair assays was 4....

Watch this Scientific Journal Video about Extraction and Analysis of Cortisol from Human and Monkey Hair at JoVE.com

Extraction and Analysis of Cortisol from Human and Monkey Hair

Cortisol (CORT) accumulates in the growing hair shaft of humans and nonhuman primates. We describe methods for extracting and analyzing hair CORT with high precision and sensitivity. Measurement of hair CORT is particularly well-suited for assessing chronic stress over periods of weeks to months.

The stress hormone cortisol (CORT) is slowly incorporated into the growing hair shaft of humans, nonhuman primates, and other mammals. We developed and ...

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