Hepatotoxic effects of sildenafil-containing “Tiger King” herbal supplement in a rat model: An in vitro and in vivo study
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Abstract
Background: The global market for erectile dysfunction (ED) treatments has seen a rise in herbal supplements marketed as natural alternatives to prescription medications. However, many of these products contain undeclared pharmaceutical ingredients, posing significant health risks.
Objective: This study aimed to investigate the chemical composition and potential hepatotoxic effects of “Tiger King,” a purported Chinese herbal supplement for sexual enhancement, using both in vitro and in vivo experiments.
Materials and methods: Chemical analysis of “Tiger King” tablets was performed using thin-layer chromatography and colorimetric tests. Antioxidant activities were evaluated using DPPH and FRAP assays. In vivo studies were conducted using male Wistar rats (N=20) divided into four groups: control, clomiphene, low-dose “Tiger King” (5 mg/kg) or TK1, and high-dose “Tiger King” (10 mg/kg) or TK2. Treatments were administered orally for 30 days. Serum testosterone levels, sperm parameters, oxidative stress markers, liver and kidney function tests, and histopathological changes were assessed.
Results: Chemical analysis revealed the presence of sildenafil in “Tiger King” tablets, with no detectable amounts of the claimed herbal ingredients. In vivo studies showed significant increases in sperm count and testosterone levels in treated groups. However, oxidative stress markers (MDA, GSH) were significantly altered, and liver function tests (ALT, AST, ALP, bilirubin) were elevated in treatment groups with ALT increased by 17.8% (from 45.0±1.1 to 53.0±1.1 U/L), AST by 12.5% (from 120.0±1.1 to 135.0±1.1 U/L) in the high-dose TK2 group. Histopathological examination revealed mild to moderate changes in liver, kidney, and reproductive organs of treated animals, including hepatic steatosis, renal glomerular congestion, and glandular atrophy in reproductive tissues.
Conclusion: This study provides evidence that “Tiger King” contains undeclared sildenafil and lacks the advertised herbal components. Its use is associated with improved reproductive parameters but also with significant biochemical and histopathological changes which draw attention to potential health risks of adulterated herbal supplements.
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Personal views expressed by the contributors in their articles are not necessarily those of the Journal of Associated Medical Sciences, Faculty of Associated Medical Sciences, Chiang Mai University.
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