Hyperandrogenism associated deregulation of hippocampal adipokines may contribute to impaired memory function in mice

Abstract

The elevation of androgen is called as hyperandrogenemia. Despite endocrinological imbalances, hyperandrogenism has also been linked to slight impairment in the cognitive functions along with depression and anxiety. Since the hippocampus regulates these function and also expresses adipokines such as leptin and adiponectin, and these adipokines have also shown deregulation in the hyperandrogenised conditions. Thus, this study aimed to explore the expression of leptin, leptin receptor, adiponectin, adipoR1 and adipoR2 along with androgen receptor and estrogen receptors in the hippocampus of letrozole-induced hyperandrogenised mice. Our results showed hyperandrogenism up-regulated the expression of leptin receptor and adipoR1, while down-regulated the expression of adipoR2. The immunostaining of leptin showed increased abundance and decreased abundance of adiponectin in the hippocampus. Furthermore, expression of androgen receptor was up-regulated and estrogen receptors expressions were down-regulated in the hippocampus of hyperandrogenised mice. The marker of apoptotic protein, active caspase3 was elevated and anti-apoptotic protein; BCL2 was suppressed in the letrozole-treated mice. Thus, it can be suggested that hyperandrogenism may be associated with deregulation of adipokines and steroid signaling along with neuronal degeneration in the hippocampus, and might also be linked to behavioral issues in the hyperandrogenised conditions with declined in spatial working memory when assessed in Y-Maze test. Since, our study was aimed to explore the expression of above proteins and linking with cognitive impairment in the hyperandrogenised conditions, yet, it is speculative and requires further investigation with auxiliary behavioral tests.