Biogeochemical Evaluation of Shilajit: Testosterone-Modulating Effects, In Vivo Toxicity and Lipid Profile Analysis

Background: Shilajit is a complex mineral-organic resin derived from rocks of varied provenance, and it has been assessed here for its antioxidant activity and acute in vivo toxicity. Methods: Despite the increasing interest in shilajit as a dietary supplement, systematic data about its acute toxicity, biochemical safety, and biological effects remain limited. Results: Samples demonstrated moderate free radical scavenging ability, with IC₅₀ values between 1.657 and 3.502 mg/mL for ABTS and 2.042 to 6.011 mg/mL for DPPH. Phenolic profiling identified samples 6 and 7 as the richest in urolithin A and phenolic acids. No fatalities, clinical signs of toxicity, or notable changes in food and water consumption or body weight gain were observed during the 14-day period, suggesting minimal single acute oral toxicity (LD₅₀ > 2000 mg kg^-1). Serum analysis revealed changes in lipid and testosterone profiles. In an exploratory follow-up of the two samples with the highest free testosterone values (6 and 7), total and free testosterone were increased approximately 2.5-fold and 3.5-fold, respectively, relative to the control group. Conclusions: The tested shilajit samples were tolerated under the conditions of this study, with no mortality or overt clinical toxicity during the 14-day observation period. Histopathological examination revealed mild to moderate degenerative and necrotic changes in hepatic and renal tissues, without hepatic fibrosis or pronounced renal interstitial lesions. These findings support satisfactory single acute oral tolerability under the study conditions but do not exclude tissue effects or establish their reversibility. Further studies are warranted to assess the long-term safety of standardized shilajit resin.