Effect of dietary fish oil on mouse testosterone level and the distribution of eicosapentaenoic acid-containing phosphatidylcholine in testicular interstitium

• Testosterone was upregulated in mice that received fish oil.
• In the testicular interstitium, EPA-containing PC was distributed characteristically.
• Leydig cells have a system to incorporate EPA selectively into the plasma membrane.
• EPA may be crucial in testosterone metabolism.

Low levels of serum testosterone are characteristically associated with diabetes, coronary atherosclerosis, obstructive sleep apnea, rheumatoid arthritis, and chronic obstructive pulmonary disease. Testosterone replacement therapy is effective against many of these disorders, indicating the importance of maintaining a healthy testosterone level. In this study, we investigated the effects of fish oil on murine testosterone metabolism and analyzed the dynamics of relevant lipids in testes by matrix-assisted laser desorption ionization mass spectrometry imaging. Testosterone was upregulated in mice that received fish oil. In the testicular interstitium, eicosapentaenoic acid-containing phosphatidylcholine was distributed characteristically. These data suggest that eicosapentaenoic acid is involved in testosterone metabolism.