Fluoride Compromises Testicular Redox Sensor, Gap Junction Protein, and Metabolic Status: Amelioration by Melatonin

• Published in: Biological trace element research 2020-08, Vol.196 (2), p.552-564
• Main Authors: Kumar, Jitendra, Haldar, Chandana, Verma, Rakesh
• Format: Article
• Language: English
• Subjects: Administration, Oral; Androgen receptors; Animals; Antioxidants; Apoptosis; Bcl-2 protein; Biochemistry; Biomedical and Life Sciences; Biotechnology; Caspase-3; Catalase; Connexin 43; Connexins - antagonists & inhibitors; Connexins - metabolism; Cricetinae; Cyclooxygenase-2; Enzymatic activity; Enzyme activity; Fluorides; Forkhead protein; GA-binding protein; Glucose; Glucose transporter; Hamsters; Inflammation; Life Sciences; Lipid peroxidation; Lipids; Male; Males; Melatonin; Melatonin - administration & dosage; Melatonin - pharmacology; Metabolism; NF-κB protein; Nutrition; Oncology; Oxidation-Reduction - drug effects; Oxidoreductions; Peroxidation; Proliferating cell nuclear antigen; Protein expression; Proteins; Reproductive health; Sodium; Sodium fluoride; Sodium Fluoride - administration & dosage; Sodium Fluoride - antagonists & inhibitors; Sodium Fluoride - toxicity; Sperm; Spermatozoa; Survival; Testes; Testis - drug effects; Testis - metabolism; Testis - pathology; Testosterone
• ISSN: 0163-4984; 1559-0720
• DOI: 10.1007/s12011-019-01946-6

The excess fluoride intake has been shown to adversely affect male reproductive health. The aim of the present study was to investigate the key mechanism underlying fluoride-induced testicular dysfunction and the role of melatonin as a modulator of testicular metabolic, oxidative, and inflammatory load. The present results indicated that sodium fluoride (NaF) exposure to adult male golden hamsters severely impairs reproductive physiology as evident from markedly reduced sperm count/viability, testosterone level, androgen receptor (AR), testicular glucose transporter (GLUT-1), gap junction (connexin-43), and survival (Bcl-2) protein expression. NaF exposure markedly increased testicular oxidative load, inflammatory (NF-kB/COX-2), and apoptotic (caspase-3) protein expression. However, melatonin treatment remarkably restored testicular function as evident by normal histoarchitecture, increased sperm count/viability, enhanced antioxidant enzyme activities (SOD and Catalase), and decreased lipid peroxidation (LPO) level. In addition, melatonin treatment upregulated testicular Nrf-2/HO-I, SIRT-1/ FOXO-1, and downregulated NF-kB/COX-2 expression. Further, melatonin ameliorated NaF-induced testicular metabolic stress by modulating testicular GLUT-1expression, glucose level, and LDH activity. Furthermore, melatonin treatment enhanced testicular PCNA, Bcl-2, connexin-43, and reduced caspase-3 expression. In conclusion, we propose the molecular mechanism of fluoride-induced testicular damages and ameliorative action(s) of melatonin.