Development and Validation of an Enzyme Immunoassay for Fecal Dehydroepiandrosterone Sulfate in Japanese Macaques (Macaca fuscata)

Validation of an enzyme immunoassay for measurement of fecal dehydroepiandrosterone sulfate in gibbons and siamangs

Monitoring wildlife stress levels is essential to ensure their quality of life in captivity or in the wild. One promising method to assess the stress response is the comeasurement of glucocorticoids (GC) and dehydroepiandrosterone sulfate (DHEAS), adrenal hormones involved in the modulation of the stress response. Although noninvasive methods to measure GCs have been validated in several species, only a few studies have validated DHEAS assays. The aims of this study were (1) to describe an enzyme immunoassay (EIA) to measure DHEAS levels, (2) to validate this assay for fecal samples in gibbons and siamangs, and (3) to test hormonal stability after one freeze-thaw cycle and over time at two freezer temperatures (-20°C and -80°C). Subjects included 32 gibbons and siamangs from U.S. zoological parks. The EIA was validated analytically by parallelism and accuracy tests, and biologically by confirming a DHEAS response 1-2 days after a stressful event (accident, vaccination, or transportation) in three individuals. In addition, fecal DHEAS levels in a pregnant female were above nonpregnant/nonlactating levels and declined progressively the following parturition. The hormonal stability experiments revealed no significant changes in fecal DHEAS levels after one freeze-thaw cycle. Hormonal levels in fecal extracts were stable for 2 months, regardless of the storage temperature, with no significant differences between -20°C and -80°C conditions. The EIA described has high sensitivity and it is suitable for fecal DHEAS measurement in gibbons and siamangs, with a potential to be applied to other species.

Adrenal androgens, adrenarche, and zona reticularis: A human affair?

In humans, reticularis cells of the adrenal cortex fuel the production of androgen steroids, constituting the driver of numerous morphological changes during childhood. These steps are considered a precocious stage of sexual maturation and are grouped under the term "adrenarche". This review describes the molecular and enzymatic characteristics of the zona reticularis, along with the possible signals and mechanisms that control its emergence and the associated clinical features. We investigate the differences between species and discuss new studies such as genetic lineage tracing and transcriptomic analysis, highlighting the rodent inner cortex's cellular and molecular heterogeneity. The recent development and characterization of mouse models deficient for Prkar1a presenting with adrenocortical reticularis-like features prompt us to review our vision of the mouse adrenal gland maturation. We expect these new insights will help increase our understanding of the adrenarche process and the pathologies associated with its deregulation.

The effects of transport stress on the behaviour and adrenocortical activity of the black-and-white ruffed lemur (Varecia variegata)

The aim of this study was to assess behavioural and glucocorticoid changes in black-and-white ruffed lemur females transported for breeding purposes between Czech ZOOs. The frequency of the presented behaviour elements was recorded via direct observation. The faecal samples were collected from the floor and subsequently the faecal glucocorticoid values were determined using specifically designed assays for faecal glucocorticoid metabolite (FGM) analysis. While the frequency of certain comfort behaviour patterns decreased (P < 0.05) in response to transport and change of the environment, grooming, resting, sleeping as well as playful behaviour (chasing, climbing) were not affected (P > 0.05). No changes were found in the frequency of behaviour connected to metabolic events with the exception of defecation. Lemur females defecated more frequently (P < 0.05) in their new environment. The frequency of neither fear nor exploratory behaviour differed (P > 0.05) before and after transport. The positive effect of the novelty was shown by the reduction (P < 0.01) of behavioural signs of frustration and stereotypical behaviour after transport. In response to transport, a significant (P < 0.05) increase of FGM levels was found the second day after the transport, reaching peak levels in the morning and starting to decline to baseline levels in the afternoon. The results of both behaviour and adrenocortical activity analysis suggest that despite some presented changes in the monitored indices prior and after transport, the transportation under the studied conditions presented only a mild stressor with limited behavioural and glucocorticoid responses.