α-Linolenic acid promotes testosterone synthesis by improving mitochondrial function in primary rooster Leydig cells.

UNLABELLED

The present study aimed to investigate the direct effects of α-Linolenic acid (ALA) on the in vitro production of testosterone and the expression of key enzymes and proteins related to steroidogenesis in Leydig cells of roosters.

METHODS

Purified primary Leydig cells isolated from 65-week-old roosters were purified and treated with different concentrations of ALA treatments: (0 μm/L [control], solvent control group (DMSO), 20 μM/L, 40 μM/L, and 80 μM/L) and cell counting-8 (CCK-8) for cell viability assay, Enzyme-linked immunosorbent assay (ELISA) kit for the determination of testosterone in cell supernatants, quantitative (real-time) PCR, and analysis of activities of antioxidants catalase (CAT), superoxide dismutase (SOD) and malondialdehyde (MDA), evaluation of mitochondrial membrane potential, pro- and anti-apoptotic proteins/genes Bcl-2, Bcl-2-associated X protein (Bax), apoptosis-inducing factor (AIF) were done respectively.

RESULTS

Our results showed that ALA significantly increased testosterone secretion in primary rooster Leydig cells (P < 0.05), and 40 μM/L is the optimal dose. Leydig cells supplemented with ALA (20, 40, 80 μM) increased the expression of key enzymes and proteins 3β-hydroxysteroid dehydrogenase (3β-HSD), steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme (P450scc) concerning steroidogenesis, enhanced antioxidant capability, improved mitochondrial biogenesis, and markedly improved the mitochondrial membrane potential (P < 0.05). Furthermore, the expression of the apoptosis-suppressive gene Bcl-2 was significantly increased, but Bax and AIF expression was decreased in the ALA group compared to that in the control group (P < 0.05).

CONCLUSION

ALA promoted testosterone production, enhanced steroidogenic enzyme expression, improved mitochondrial function, and antioxidant capacity, and reduced apoptosis in primary rooster Leydig cells, with 40 μM/L identified as the optimal concentration.