EFFECTS OF MOON SEED VINE (Triclisia gilletiiSTANER) ON ETHANE-1,2-DIOL-INDUCED NEPHROLITHIASIS AND RENOTOXICITY IN WISTAR RATS

Abstract

Moonseed vine (Triclisia gilletii Staner) in the family Menispermaceae is used locally in Nigeria for the management of renal-related ailments. Phytochemical screening, characterization of Triclisia gilletii aqueous methanolic leaf extract (TGAMLE) with high performance liquid chromatography-mass spectrometer (HPLC-MS), gas chromatography-mass spectrometer (GC-MS) were carried out.Lethal dose (LD50), in vitro antioxidant (2,2-diphenyl-1-picrylhydrazyl (DPPH), cupric reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP) ability and anti-nucleation activity were also performed. Toxicity testing of 10, 100 and 1000 mg/kg b.w. TGAMLEwere investigated by nephrochemical assays (creatinine, urea, uric acid, lactate dehydrogenase, alanine amino transferase, aspartate aminotransferase). Nephrolithiasis was induced in male Wistar rats with 1% ethane-1,2-diol in drinking water ad libithum for 28 days with or without co-administration of 50, 100, and 200 mg/kg b.w. TGAMLE or 5 μg/kg b.w. tamsulosin hydrochloride (TH). Urinalysis and levels of creatinine, urea, uric acid, electrolytes (calcium, potassium, sodium, chloride, and bicarbonate) glucose, total protein, and albumin were accessed in both plasma and urine. Markers of redox status (malondialdehyde (MDA), reducedglutathione (GSH), protein carbonyl (PC), FRAP, glutathione peroxidase (GPx), superoxide dismutase (SOD)), anti-inflammatory; myeloperoxidase (MPO), and markers of membrane integrity (complex-I, glutamine synthetase (GS), Na+/K+-ATPase, lactate dehydrogenase (LDH) activity), as well as histopathology of the kidney were assessed.Compounds derived from Triclisia gilletiiand TH was docked with homology model of crystal binding molecule CD44in silico.Quercetin (20 mg/kg), oleanolic acid (10 mg/kg), stigmasterol (20 mg/kg), and sitosterol (20 mg/kg) plus TGAMLE (100 mg/kg) were investigated against ethane-1,2-diol administered rats. The mRNA expression of CD44 and osteopontin (OPN) and antioxidant marker genes (nuclear factor erythroid- 2 – related factor- 2 (Nrf2) and Heme oxygenase-1 (HO-1)) were assessed. The results showed that phenols, steroids, saponins, flavonoids, were present in GC-MS analysis of TGAMLE. HPLC-MS afforded the characterization of kaempferol and caffeic acid derivatives.The total antioxidant capacity was (30.36 ± 1.90 mg GAE/g extract and TGAMLE was considered relatively safe with LD50 greater than 5000 mg/kg b.w. and in vitro anti-nucleation activity (IC50 = 7.09 mg/ml). Calcium oxalate stone formation as a result of oxalates from ethane-1,2-diol was evident by hypocalcemia, and further electrolyte imbalance, and decreased glomerular filtration rate. Enhanced oxidative milieu in hyperoxaluria was evident by increased MDA, PC and decreased enzymatic and non-enzymatic antioxidants as well as renal membrane enzyme activities. The renal histopathological study further emphasized oxalate-induced damage. II'-hydroxy-4'-methoxyochnaflavone had the highest interaction with CD44. Ethane-1,2-diol administration up-regulated mRNA expression of CD44 and down-regulated antioxidant marker genes (Nrf2 and HO-1) with no significant difference on OPN mRNA expression when compared with control. TGAMLEand its derived compounds significantly modified crystal binding molecules and up-regulated the expression of antioxidant genes investigated. Conclusively, abnormal biochemical, redox electrolyte, membrane integrity and histological alterations as a result of ad libithum exposure of rats to ethane-1,2-diol were attenuated by TGAMLE via Nrf2/HO-1 mechanistic pathway leading to modulation of crystal binding molecules. Overall, additive effects of the compounds present in the extract revealed a better efficacy and revealed Triclisia gilletii as a nephroprotectant.