Metabolic and Endocrine Responses of Desert-Adapted Mice Reproductive System to Increased Salinity

From an evolutionary point of view, reproduction timing is an important adaptation which enables the transfer of genetic properties, thus enabling species continuation. Rodents inhabiting arid environments need reliable cues for triggering their reproduction. Results of previous studies showed that increased dietary salinity plays an important role as an ultimate regulator for desert adapted rodents’ reproductive system. The authors aimed discovering pathways by which high salinity can affect the reproductive system and metabolic status of desert adapted common spiny mice, Acomys cahirinus. Mice were challenged with osmotic stress, water source salinity increased gradually from 0.9% - 5% NaCl under short days (SD) and long days (LD). The authors assessed leptin and free fatty acid (FFA) levels using ELISA while, SYBR green technology was used for relative receptor expression (RQ) of target genes. Results revealed that serum levels of the hormone leptin were significantly (P < 0.05) reduced in salinity treated (ST) mice. Levels of FFA were significantly (P < 0.05) increased in LD- and SD-ST-males. In ST-SD females a significant increase (P < 0.05) in expression levels of leptin (Ob-Rt) mRNA receptor gene, in ovaries was noted. Aldosteron (Nr3c2) and vasopressin (AVP) mRNA receptor expression genes levels were significantly (P < 0.05) increased in both LD- and SD- ST- males.