Dear MARMAM community,

My coauthors and I are excited to announce our recent paper on hormone analyses in small blubber samples (50 mg) of gray and fin whales published in Frontiers in Marine Science. It is  open access and can be found here:

https://www.frontiersin.org/articles/10.3389/fmars.2021.808764/full

Wittmaack C, Urbán Ramírez J, Bernot-Simon D, Martínez-Aguilar S, Subbiah S, Surles JG, Looney M, Kumar N, Halaska B, Duignan PJ, Knauss M, Burns K and Godard-Codding CAJ (2022).  Small Blubber Samples (50 mg) Sufficient for Analyses of 10 Stress and Reproductive Steroid Hormones in Gray and Fin Whales via Liquid Chromatography Mass Spectrometry. Front. Mar. Sci. 8:808764.

doi: 10.3389/fmars.2021.808764

ABSTRACT

Information on stress, reproductive fitness, and health is difficult to obtain in wild

cetaceans but critical for conservation and management. The goal of this study was to

develop a methodology requiring minimal blubber mass for analysis of reproductive and

stress steroid hormones and, hence, suitable for cetacean biopsies. Blubber biopsies

and samples were collected from free-ranging and stranded gray and fin whales. Steroid

hormones were extracted from blubber samples as small as 50 mg using liquid-liquid

extraction methodology developed to handle the high fat content of blubber.

Samples were analyzed via liquid chromatography with tandem mass spectrometry

for 10 hormones: aldosterone, androstenedione, cortisol, cortisone, corticosterone,

17b-estradiol, estrone, 17a-hydroxyprogesterone, progesterone, and testosterone. As

part of the optimization, homogenization via bead beating and blade dispersion were

compared, and the former found superior. To investigate optimal yet minimal tissue mass

required, hormone panels were compared among paired 50, 150, and 400 mg samples,

the latter two being commonly reported masses for hormone blubber analysis. Results

indicated that 50 mg of blubber was suitable and sometimes superior. Additionally,

significant differences in precision values were observed between species, possibly

stemming from differences in blubber composition, and relevant to homogenization

technique selection and calibration methods that use blubber matrix matches obtained

from a species other than the study species. Based on recovery and precision values,

our methodology was accurate and precise in the measurement of spiked known

quantities for all 10 hormones, confirming the methodology capabilities in 50 mg blubber

mass in both species. Altogether, and in our specific sample sets, all endogenous

hormones, except corticosterone, were identified above the detection limit in 50 mg gray

whale blubber samples while all endogenous hormones, except aldosterone, cortisone,

Please feel free to contact me at celine.godard@ttu.edu

Best,

Céline Godard-Codding

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Céline Godard-Codding, Ph.D.

Professor and Associate Chair

Department of Environmental Toxicology

The Institute of Environmental and Human Health

Texas Tech University and TTU Health Sciences Center

Box 41163

Lubbock, Texas 79409-1163

Office: (806)-834-2737

Fax:    (806)-885-2132

FEDEX shipping address:

The Institute of Environmental and Human Health (TIEHH)

Reese Technology Center Building 555

1207 S. Gilbert Drive

Lubbock TX 79416-2103

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