Exploring the potential of flunarizine for Cisplatin-induced painful uremic neuropathy in rats.

PURPOSE: The present study was designed to explore the potential of flunarizine for cisplatin induced painful uremic neuropathy in rats. METHODS: Cisplatin (2 mg/kg; i.p., for 5 consecutive days) was administered and renal uremic markers i.e., serum creatinine were estimated on days 4 and 25. Behavioral changes were assessed in terms of thermal hyperalgesia (hot plate, plantar, tail immersion, and tail flick tests at different time intervals). Biochemical analysis of total calcium, superoxide anion, DNA, and transketolase, and myeloperoxidase activity in tissue samples was also performed. Furthermore, flunarizine (100, 200, and 300 µM/kg; p.o., for 21 consecutive days) was administered to evaluate its potency on uremic neuropathy, and the results were compared with those for the carbamazepine-treated (30 mg/kg; p.o., for 21 consecutive days) groups. RESULTS: Flunarizine attenuated the cisplatin-induced uremic neuropathy, and the degree of behavioral and biochemical changes in serum and tissue samples in a dose dependent manner. The medium and high doses of flunarizine were shown to produce a significant effect on cisplatin induced painful uremic neuropathy. CONCLUSIONS: Our results indicate the potential of flunarizine for anti-oxidative, anti-inflammatory, and neuroprotective actions. Therefore, it may have use as a novel therapeutic agent for the management of painful uremic neuropathy.

Reno-protective role of flunarizine (mitochondrial permeability transition pore inactivator) against gentamicin induced nephrotoxicity in rats.

This study was aimed to evaluate the role of flunarizine on gentamicin (GEM) induced nephrotoxicity in rat. Administration of GEM (40 mg/kg, s.c. for 10 consecutive days) significantly increased blood urea nitrogen (BUN), N-acetyl ß-d-glucosaminidase (NAG), thiobarbituric acid reactive substances (TBARS) and total calcium whereas, decreased body weight, fractional excretion of sodium (FrNa), creatinine clearance (CrCl), reduced glutathione (GSH), mitochondrial cytochrome c oxidase (Cyt-C oxidase) and ATP levels resulting in nephrotoxicity. Further, flunarizine (100, 200 and 300 µmol/kg, p.o.) was administered to evaluate its renoprotective effect against GEM induced nephrotoxicity and the results were compared with cylcosporin A (CsA, 50 µmol/kg, p.o.). Flunarizine resulted in the attenuation of renal dysfunction and oxidative marker changes in rats subjected to GEM induced nephrotoxicity in a dose dependent manner. Medium and higher doses of flunarizine produced significant renal protective effect which was comparable to cyclosporin A. The results of this study clearly revealed that flunarizine protected the kidney against the nephrotoxic effect of GEM via mitochondrial permeability transition pore (MPTP) inactivation potential.

The antiinflammatory potential of phenolic compounds from Emblica officinalis L. in rat.

Antiinflammatory effects of phenolic compounds from Emblica officinalis were evaluated in carrageenan and cotton pellet induced acute and chronic inflammatory animal model. Fractions of E. officinalis containing free (FPEO) and bounded (BPEO) phenolic compounds were assessed by HPLC technique. The free and bound phenolic compounds were studied for their acute and chronic antiinflammatory activity at dose level of 20 and 40 mg/kg. The carrageenan induced acute inflammation was assessed by measuring rat paw volume at different time of intervals. Further, cotton pellet induced chronic inflammation was assessed by granulomatous tissue mass estimation along with the estimation of tissue biomarker changes (i.e. lipid peroxidation, reduced glutathione, myeloperoxidase and plasma extravasation). The results indicated that in both acute and chronic inflammation, FPEO and BPEO show reduction in the inflammation, but significant effects was observed only at high doses of both fractions which was comparable to diclofenac treated group. In conclusion, phenolic compounds of E. officinalis may serve as potential herbal candidate for amelioration of acute and chronic inflammation due to their modulatory action of free radicals.

Ameliorative effect of flunarizine in cisplatin-induced acute renal failure via mitochondrial permeability transition pore inactivation in rats.

This study was aimed to evaluate the protective effect of flunarizine on cisplatin-induced acute renal failure. Administration of cisplatin (6 mg/kg, i.p. on day 6) significantly increased serum blood urea nitrogen and creatinine, urinary N-acetyl ß-D-glucosaminidase, tissue thiobarbituric acid reactive substances and total calcium whereas, decreased body weight, fractional excretion of sodium, creatinine clearance tissue-reduced glutathione, mitochondrial cytochrome c oxidase, and ATP levels were observed in acute renal failure rats. Moreover, cisplatin produced histopathological changes in the renal tissue. Furthermore, flunarizine (100, 200, and 300 µM/kg, p.o., for six consecutive days) was administered to evaluate its therapeutic potential in acute renal failure, and the results were compared with cyclosporin A (50 µM/kg, p.o., for six consecutive days) as a reference drug. Flunarizine resulted in the attenuation of cisplatin-induced renal dysfunction, oxidative stress marker, mitochondrial damage, and histopathological changes in rats. Medium and higher doses of flunarizine produced significant renal protective effect which was comparable to cyclosporin A. The results of this study clearly revealed that flunarizine protected the kidney against the nephrotoxic effect of cisplatin via mitochondrial permeability transition pore inactivation potential.