Acute and sub-chronic oral toxicity studies of hesperidin isolated from orange peel extract in Sprague Dawley rats.

Citrus sinensis contains glycoside hesperetin-7-rhamnoglucoside (hesperidin) which harbor an array of therapeutic potentials including antioxidant, anticancer, and anti-inflammatory. However, a systematic examination of safety is needed before its utilization. Hence, the present investigation is aimed to evaluate acute and sub-chronic toxicity of hesperidin isolated from the citrus fruit. Hesperidin (73%) was isolated from a methanolic extract of dried peel of the citrus fruit, characterized using FTIR, and standardized by HPLC. Its acute oral toxicity (AOT) and sub-chronic toxicity studies were carried out in Sprague-Dawley rats. Hesperidin (5000 mg/kg) showed 10% mortality in AOT. In sub-chronic toxicity study, hesperidin (250 and 500 mg/kg) did not induce any abnormalities in body weight, food consumption, clinical signs, ophthalmological and neurological observations, urine analysis, hematology, clinical chemistry, organ weights, and gross pathology. However, hesperidin (1000 mg/kg) showed significant (p < 0.05) alterations in body and organ weights, hematology, clinical chemistry, and tissue histopathology. To conclude, hesperidin has median lethal dose (LD50) of 4837.5 mg/kg, and Low Observed Adverse Effect Level (LOAEL) at 1000 mg/kg for both male and female Sprague-Dawley rats. Thus, hesperidin isolated from citrus fruit showed a good safety profile in animal study.

Elucidation of protective efficacy of Pentahydroxy flavone isolated from Madhuca indica against arsenite-induced cardiomyopathy: Role of Nrf-2, PPAR-γ, c-fos and c-jun.

BACKGROUND: Madhuca indica J. F. Gmel. (Sapotaceae) is widely used ethnobotanically as anti-diabetic, antipyretic, hepatoprotective, anti-inflammatory and analgesic. It was shown to possess potent anti-apoptotic property. THE AIM OF THE STUDY: To evaluate the possible mechanism of action of isolated phytoconstituent from Madhuca indica Leaves methanolic extract (MI-ALC) on arsenic-induced cardiotoxicity in rats. MATERIALS AND METHODS: The 3,5,7,3',4'-Pentahydroxy flavone (QTN) was isolated and characterized by using HPTLC, 1H NMR, and LC-MS from MI-ALC. QTN (5, 10 and 20mg/kg, p.o.) was administered in arsenic intoxicated rats (5mL/kg, p.o.) for 28days and evaluated for various behavioral, biochemical, molecular and ultra-histological changes. RESULTS: Treatment with QTN (10 and 20mg/kg, p.o.) significantly inhibited (p<0.05) arsenic-induced electrocardiographic, hemodynamic and left ventricular function alterations. Elevated levels of cardiac markers (LDH, CK-MB, AST, ALT, and ALP), altered lipid metabolism (total cholesterol, triglyceride, LDL, HDL, and VLDL) was significantly restored (p<0.05) by QTN. It also significantly inhibited (p<0.05) altered cardiac oxido-nitrosative stress, Na-K-ATPase level and mitochondrial enzymes (I-IV) activity after arsenite administration. QTN significantly increased (p<0.05) myocardial Nrf-2, PPAR-γ and significantly decreased (p<0.05) myocardial c-fos and c-jun mRNA expressions. Flow cytometric analysis showed that treatment with QTN (10 and 20mg/kg) significantly inhibited (p<0.05) arsenite-induce ROS and apoptosis. It also reduced ultra-histological aberrations induced by sodium arsenite. CONCLUSION: Administration of 3,5,7,3',4'- Pentahydroxy flavone (i.e. Quercetin (QTN)) isolated from MI-ALC showed significant protection against arsenic-induced oxido-nitrosative stress and myocardial injury via modulation of Nrf2, PPAR-γ, and apoptosis.