Abstract:
Infertility is a prevalent health condition and 50% of its prevalence is related to male factor. Exposure to testicular toxicants such as Alcohol (A) and Nicotine (N) contributes to male infertility via induction of oxidative stress. Antioxidants such as Quercetin (Q), have been reported to enhance fertility. However, there is paucity of information on the effects of quercetin in A- and N-induced reproductive toxicity. This study was carried out to examine the modulatory activity of quercetin on reproductive functions in A- and N-treated male Wistar rats.
Ninety male Wistar rats (180-200 g) were divided into two studies of forty-five animals each. Each study had nine groups (n=5) and treated orally as follows: Control (distilled water), Corn oil (CnO) (2 mL/kg, Corn oil), Q (30 mg/kg, quercetin), A (3 mL/kg, alcohol), N (1 mg/kg, nicotine), A+N (3 mL/kg, alcohol+1 mg/kg, nicotine), A+Q (3 mL/kg, alcohol+30 mg/kg, quercetin), N+Q (1 mg/kg, nicotine+30 mg/kg, quercetin), A+N+Q (3 mL/kg, alcohol+1 mg/kg, nicotine+30 mg/kg, quercetin) for 52 days. Forty-five untreated female rats were cohabited with the second 45 treated male rats in study two for mating. Experimental animals were sacrificed by cervical dislocation; blood samples were obtained for hormonal assay and selected organs (hypothalamus, pituitary, testis, seminal vesicle, epididymis) were harvested. Follicle Stimulatinf Hormone (FSH), Luteinizing Hormone (LH) and testosterone levels were assayed by microscopy. Immunoexpression of apoptotic factor (p53), antiapoptotic protein (Bcl2), proliferative factors (Ki67 and EGFR) and cell cycle regulator (CYD) were determined by Immunohistochemistry. Fragmentation of DNA was determined by Agarose gel electrophoresis. Data were subjected to descriptive statistics using ANOVA at α0.05.
Mature sperm, sperm count and motility significantly decreased (P˂0.05) in A+N (50.0±2.7 %; 31.0±1.0×106 cell/mL; 34.0±1.1%) compared with control (86.0±2.5%; 96.0±1.9×106 cell/mL; 90.0±1.6%) A+Q (75.0±2.2%; 88.0±3.0×106 cell/mL; 80.0±3.5%), N+Q (75.0±2.0; 88.0±2.0×106 cell/mL ; 83.0±2.6%) and A+N+Q (76.0±1.8%; 70.0±2.2 106 cell/mL; 80.0±2.7%). Serum FSH, LH and testosterone reduced in A+N (2.6±0.6 mIU/mL; 1.6±0.2 mIU/mL; 1.2±0.4 ng/mL) compared with control (8.3±0.6 mIU/mL; 5.0±0.4 mIU/mL; 4.2±0.4 ng/mL) and A+N+Q (5.6±0.5 mIU/mL; 3.5±0.3 mIU/mL; 3.1±0.3 ng/mL). Testicular MDA significantly increased in A+N (165.0±3.03 µmol/mg protein), N+Q (102.0±4.0 µmol/mg protein), A+N+Q (104.0±6.0 µmol/mg protein) and control (96.0±0.98 µmol/mg protein). While SOD and GSH reduced in A+N (79.6±4.6 U/mg protein; 136.0±5.5 mmol/mg protein) compared with control (121.0±0.7 U/mg protein; 354.0±16.6 mmol/mg protein) and A+Q (112.0±5.1 U/mg protein; 320.0±12.6 mmol/mg protein), N+Q (110.0±5.1 U/mg protein; 323.0±23.6 mmol/mg protein) and A+N+Q (112.0±4.8 U/mg protein; 315.0±9.1 mmol/mg protein), respectively. A+N rats did not produce offspring, but A+N+Q rats did. Apototic factor (p53), testicular DNA fragmentation increased in A+N, but not in A+Q, N+Q and A+N+Q. The Bcl2, Ki67, EGFR and cell cycle CYD were increased by Q supplementation.
Quercetin ameliorated alcohol- and nicotine-induced male reproductive dysfunction by increasing sex hormone levels and sperm quality via reduction in testicular oxidative stress. Quercetin also resulted in up-regulation of proliferative factors and down-regulation of apoptotic proteins.
