Venlafaxine and carvedilol ameliorate testicular impairment and disrupted spermatogenesis in rheumatoid arthritis by targeting AMPK/ERK and PI3K/AKT/mTOR pathways

Abstract

Testicular impairment has been commonly described in long-standing rheumatoid arthritis (RA) patients. Since depression and cardiovascular disorders are the most disturbing co-morbidities of RA, investigating the efficacy of the anti-depressant venlafaxine or the beta-blocker carvedilol in RA-associated testicular dysfunction may add to their clinical utility for RA patients. Previously, both agents have demonstrated significant in vivo anti-oxidant and anti-inflammatory actions. In the current study, venlafaxine (50 mg/kg/day) and carvedilol (10 mg/kg/day) were orally administered to adjuvant arthritic rats for 20 days. Interestingly, venlafaxine and carvedilol effectively suppressed paw edema and mitigated the testicular histopathological aberrations and the disrupted spermatogenesis. Both drugs enhanced testicular steroidogenesis through upregulation of 3β-HSD, 17β-HSD and StAR gene expression with concomitant augmentation of serum testosterone. They also blunted the inflammatory burden via attenuation of myeloperoxidase, TNF-α and the protein expression of NF-κBp65 along with elevation of IL-10. They attenuated testicular oxidative perturbations via lowering lipid peroxides and nitric oxide and boosting glutathione levels. With regard to apoptosis, the two agents lowered the protein expression of caspase-3, cleaved caspase-3, cleaved PARP, Bax and p53, promoting germ cell survival. They also modulated the AMPK/ERK signaling via lowering of p-AMPK and upregulation of p-ERK1/2 along with PI3K/AKT/mTOR transduction by enhancing the PI3Kp110α, p-AKT and p-mTOR protein expression. Together, the present work demonstrates the beneficial effects of venlafaxine and carvedilol in RA testicular dysfunction and impaired spermatogenesis via modulation of AMPK/ERK and PI3K/AKT/mTOR signaling and intervention with the testicular oxidative stress, inflammation and apoptosis.