DOSE-DEPENDENT FLUORIDE TOXICITY DISRUPTS STEROIDOGENESIS AND TESTICULAR HISTOLOGY IN WISTAR RATS: CORRELATIVE INSIGHTS
DOI:
https://doi.org/10.22159/ijpps.2026v18i6.58480Keywords:
Fluoride, Steroidogenesis, Intratesticular testosterone, 3β-hydroxysteroid dehydrogenase, 17β-hydroxysteroid dehydrogenase, Germ cell apoptosisAbstract
Objective: This study aimed to correlate intratesticular testosterone levels with histopathological changes in testes of male rats exposed to fluoride-induced infertility, alongside evaluations of 3β- and 17β-hydroxysteroid dehydrogenase (HSD) activities.
Methods: Male wistar albino rats (n=24, 100–150 g) were divided into four groups (n=6 each): control (fluoride-free deionized water) and NaF-treated (100, 200, 300 ppm) for 40 days, as per CPCSEA guidelines with institutional ethical clearance. Endpoints included body/testis weights, germ cell viability (MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay), steroidogenic enzymes (3β-HSD, 17β-HSD via spectrophotometry), and intratesticular testosterone (ELISA). Data were analyzed by one-way ANOVA with Tukey post-hoc test (SAS 9.4/SPSS 17) with p<0.05).
Results: NaF induced dose-dependent reductions in body weight (75% at 300 ppm, p<0.0001), testis weight (62.63%, p<0.0001), germ cell viability, testosterone, and HSD activities. Strong correlations emerged: germ cell viability with testosterone (r=0.865), 3β-HSD (r=0.936), and 17β-HSD (r=0.852). Histopathology showed vacuolated seminiferous tubules, Leydig cell atrophy, and disrupted spermatogenesis.
Conclusion: Sodium fluoride disrupts testicular steroidogenesis through HSD enzyme inhibition, lowering intratesticular testosterone and inducing germ cell apoptosis. These findings highlight fluoride as an environmental reproductive toxicant, support the development of antioxidant therapeutics for fluoride-endemic regions, and advance pharmaceutical toxicology.
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