Ontogeny of adropin and its receptor expression during postnatal development and its pro-gonadal role in the ovary of pre-pubertal mouse

Adropin promotes testicular functions by modulating redox homeostasis in adult mouse

PURPOSE

Adropin is an emerging metabolic hormone that has a role in regulating energy homeostasis. The present study aimed to explore the impact of adropin on redox homeostasis and its possible role in testicular functions in adult mouse testis.

METHODS

Western blot, flow-cytometry, and TUNEL assay were performed to explore the impact of intra-testicular treatment of adropin (0.5 μg/testis) on testicular functions of adult mice. Hormonal assay was done by ELISA. Further, antioxidant enzyme activities were measured.

RESULTS

Adropin treatment significantly increased the sperm count and testicular testosterone by increasing the expression of GPR19 and steroidogenic proteins. Also, adropin treatment reduced the oxidative/nitrosative stress by facilitating the translocation of NRF2 and inhibiting NF-κB into the nucleus of germ cells. Enhanced nuclear translocation of NRF2 leads to elevated biosynthesis of antioxidant enzymes, evident by increased HO-1, SOD, and catalase activity that ultimately resulted into declined LPO levels in adropin-treated mice testes. Furthermore, adropin decreased nuclear translocation of NF-κB in germ cells, that resulted into decreased NO production leading to decreased nitrosative stress. Adropin/GPR19 signaling significantly increased its differentiation, proliferation, and survival of germ cells by elevating the expression of PCNA and declining caspase 3, cleaved caspase 3 expression, Bax/Bcl2 ratio, and TUNEL-positive cells. FACS analysis revealed that adropin treatment enhances overall turnover of testicular cells leading to rise in production of advanced germ cells, notably spermatids.

CONCLUSION

The present study indicated that adropin improves testicular steroidogenesis, spermatogenesis via modulating redox potential and could be a promising target for treating testicular dysfunctions.

Adropin may regulate ovarian functions by improving antioxidant potential in adult mouse

The corpus luteum (CL) is a temporary endocrine gland that synthesizes progesterone. The luteal progesterone plays a central role in the regulation of the estrous cycle as well as the implantation and maintenance of pregnancy. Our previous study showed the expression of adropin and its receptor, GPR19, in the luteal cells and its significant role in luteinization. The aim of the present study was to investigate the in vitro effect of adropin on hCG-induced ovarian functions in adult mice. We also evaluated the effect of exogenous treatment with adropin on ovarian steroidogenesis and anti-oxidant parameters, with special emphasis on CL function. Our results demonstrated that adropin acts synergistically with hCG to promote ovarian steroidogenesis and survival by increasing the expression of StAR, 3β-HSD, and aromatase proteins and decreasing the BAX/BCL2 ratio. Exogenous adropin treatment increased progesterone production by increasing the expression of GPR19, StAR and 3β-HSD enzymes in the mouse ovary. Also, adropin inhibited the luteal oxidative stress by increasing nuclear translocation of NRF-2 in CL, which resulted in increased HO-1 expression and SOD, catalase activity. Decreased oxidative stress might inhibit the translocation of NF-κB into the nucleus of luteal cells, resulting into increased survival and decreased apoptosis, as evident by decreased lipid peroxidation, BAX/BCL2 ratio, caspase 3, active caspase 3 expression, and TUNEL-positive cells in adropin treated mice. Our findings suggest that adropin can be a promising candidate that can enhance the survivability of the CL.

Adropin: A crucial regulator of cardiovascular health and metabolic balance

Adropin, a peptide discovered in 2008, has gained recognition as a key regulator of cardiovascular health and metabolic balance. Initially identified for its roles in energy balance, lipid metabolism, and glucose regulation, adropin has also been found to improve cardiovascular health by enhancing endothelial function, modulating lipid profiles, and reducing oxidative stress. These protective mechanisms suggest that adropin may be able to help prevent conditions such as atherosclerosis, hypertension, and other cardiovascular diseases. Research has established connections between adropin and cardiovascular risk factors, such as obesity, insulin resistance, and dyslipidemia, positioning it as a valuable biomarker for evaluating cardiovascular disease risk. New studies highlight adropin's diagnostic and prognostic significance, showing that higher levels are linked to better cardiovascular outcomes, while lower levels are associated with a higher risk of cardiovascular diseases. This review aims to summarize current knowledge on adropin, emphasizing its significance as a promising focus in the intersection of cardiovascular health and metabolic health. By summarizing the latest research findings, this review aims to offer insights into the potential applications of adropin in both clinical practice and research, leading to a deeper understanding of its role in maintaining cardiovascular and metabolic health.