Ameliorative effect of Koflet formulations against pyridine-induced pharyngitis in rats.

In present study two formulations of Koflet (syrup and lozenges) were evaluated against pyridine-induced pharyngitis in rats. Topical application of 10% pyridine showed extravasation of Evans blue stain as a characteristic feature of on-going inflammation. In addition, the levels of TNF-α (p < 0.01) and IL-6 (p < 0.01) were significantly increased compared to control. Further, histopathology of the pharyngeal tissue showed submucosal gland hypertrophy, severe mucosal inflammation characterized by presence of mononuclear cells and neutrophils along with haemorrhages and congestion; however, saline applied animals (normal control) showed normal cytoarchitecture of the pharynx. Interestingly, pre-treatment with dexamethasone (1 mg/kg, p.o.), Koflet lozenges (KL) (500 and 1000 mg/kg, p.o.) and Koflet syrup (KS) (2 and 4 ml/kg, p.o.) for 7 days showed significant and dose dependent protection by decreasing the EB dye extravasation, and serum levels of TNF-α and IL-6. In addition, histopathological findings have further supported the protective effect of Koflet formulations. These findings suggest that, both Koflet syrup and Koflet lozenges are highly effective in treating non-infectious type of pharyngitis. Among the two formulations KS was found to be more potent than KL, and possible mechanism of action thought to be mediating through inhibition of TNF-α and/or phospholipids-arachidonic acid pathway.

Novel experimental model of non-infectious pharyngitis in rats.

INTRODUCTION: Currently, there is a paucity of scientific literature and reports related to screening models for non-infectious type of pharyngitis. In this context, we made a sincere attempt to establish a novel animal model for screening drugs against non-infectious pharyngitis in rats. We have considered the use of pyridine, croton oil and their combination for inducing non-infectious pharyngitis in rats. METHODS: Various concentrations of pyridine were applied topically to the pharyngeal region of rats and the extent of inflammation was assessed by Evans Blue (EB) dye exudation test, evaluating the serum levels of proinflammatory cytokines and histopathology. Dexamethasone and diclofenac were used as reference standards. RESULTS: Upon pyridine application (2.5%, 5%, 10%, 20%, 40% and 80% in saline), dose-dependent increase in EB dye extravasation was observed (increased vascular permeability). In addition, the levels of TNF-α (P<0.01) and IL-6 (P<0.01) were significantly increased compared to control. Furthermore, the histopathology of pharyngeal tissue showed hypertrophy of submucosal glands, severe inflammation of the pharynx characterised by presence of mononuclear cells, neutrophils along with haemorrhages and congestion; however, normal control animals showed normal cytoarchitecture of pharynx. Indeed, dexamethasone (0.25, 0.5 and 1 mg/kg, i.v.) and diclofenac (1, 2.5 and 5 mg/kg, i.v.) showed dose-dependent protection against pyridine-induced pharyngitis. Further, the possible mechanism of pyridine-induced pharyngitis is thought to be primarily mediated through phospholipase A2 and cyclooxygenase (COX) pathway. CONCLUSION: These findings suggest that pyridine-induced pharyngitis is a simple and versatile novel animal model for screening the drugs against non-infectious pharyngitis in rats.

Cardioprotective effect of Saraca indica against cyclophosphamide induced cardiotoxicity in rats: a biochemical, electrocardiographic and histopathological study.

OBJECTIVES: Cardioprotective activity of alcoholic extract of Saraca indica (SI) bark was investigated against cyclophosphamide induced cardiotoxicity. MATERIALS AND METHODS: Cardiotoxicity was induced in Wistar rats by administering cyclophosphamide (200 mg/kg, i.p.) single injection on first day of experimental period. Saraca indica (200 and 400 mg/kg, p.o.) was administered immediately after administration of cyclophosphamide on first day and daily for 10 days. The general observations and mortality were measured. RESULTS: Cyclophosphamide administration significantly (p < 0.05) increased lipid peroxidation (LPO) and decreased the levels of antioxidant markers such as reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). Cyclophosphamide elevated the levels of biomarker enzymes like creatine kinase (CK), creatine kinase isoenzyme MB (CK-MB), lactate dehydrogenase (LDH), aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP). Further, the cyclophosphamide treated rats showed changes in electrocardiogram (ECG) along with increased levels of cholesterol and triglycerides. Treatment with Saraca indica significantly (p < 0.05) reversed the status of cardiac biomarkers, ECG, oxidative enzymes and lipid profile in cyclophosphamide induced cardiotoxicity. Potential cardioprotective effect of Saraca indica was supported by histopathological examination that reduced severity of cellular damage of the myocardium. CONCLUSION: The biochemical, ECG and histopathology reports support the cardioprotective effect of Saraca indica which could be attributed to antioxidant activity.

Neuroprotective Activity of Pongamia pinnata in Monosodium Glutamate-induced Neurotoxicity in Rats.

This study was designed to evaluate the neuroprotective activity of ethanol extract of Pongamia pinnata stem bark in monosodium glutamate-induced neurotoxicity in rats. Neurotoxicity was induced by intraperitoneal injection of monosodium glutamate 2 g per kg body weight daily for 7 days. Ethanol extract of Pongamia pinnata stem bark (200 and 400 mg/kg) was administered orally after 1 h of monosodium glutamate treatment. Dextromethorphan (30 mg/kg, p.o.) was used as standard drug for the comparison. The degree of protection was determined by various behavioural, locomotor, muscle grip activity, lipid peroxidation and measurement of antioxidant status of glutathione, catalase and superoxide dismutase. Estimation of calcium, sodium and potassium ions in brain tissue and gamma aminobutyric acid level in serum was carried out. The histopathological study of brain tissue was also carried out. Treatment with Pongamia pinnata significantly improved monosodium glutamate-induced alteration in behavioural and locomotor activity and muscle strength. Significant decrease in lipid peroxidation and increase in glutathione, superoxide dismutase and catalase was observed in Pongamia pinnata treated group. Further, Pongamia pinnata also significantly reduced the monosodium glutamate-induced excitotoxicity by decreasing the level of Ca(+2) and Na(+) with concomitant increase in the level of K(+). Serum gamma aminobutyric acid level was also increased in Pongamia pinnata treated animals. Further, the histopathological evidence supports the neuroprotective activity of Pongamia pinnata. In conclusion, the present study suggests that the ethanol extract of stem bark of Pongamia pinnata possesses significant neuroprotective activity in albino rats.

Hepatoprotective Effect of Cissus quadrangularis Stem Extract Against Rifampicin-induced Hepatotoxicity in Rats.

The study was designed to investigate the hepatoprotective activity of methanol extract of Cissus quadrangularis against rifampicin-induced hepatotoxicity in rats.The coarse powder of the shade dried stem of Cissus quadrangularis was subjected to successive extraction in a Soxhlet apparatus using solvents petroleum ether (60-80°) and methanol. Liver damage was induced in Wistar rats by administering rifampicin (54 mg/kg, p.o.) once daily for 30 days. Methanol extract of Cissus quadrangularis (500 mg/kg, p.o) was administered 1 h prior to the administration of rifampicin (54 mg/kg, p.o.) once daily for 30 days. Silymarin (50 mg/kg p.o) used as reference drug. Elevated levels of aspartate transaminase, alanine transaminase, alkaline posphatase and bilirubin following rifampicin induction were significantly lowered due to pretreatment with methanol extract of Cissus quadrangularis. Rifampicin administration significantly increased lipid peroxidation and decreased antioxidant activities like reduced glutathione, superoxide dismutas and catalase. Pretreatment of rats with methanol extract of Cissus quadrangularis significantly decreased lipid peroxidation and increased the antioxidant activities. Histology of the liver section of the animals treated with the methanol extract of Cissus quadrangularis further confirms the hepatoprotective activity. The results of the present study indicated the hepatoprotective effect of methanol extract of Cissus quadrangularis which might be ascribable to its antioxidant property due to the presence of ß-carotene.

Cardioprotective effect of ascorbic acid on doxorubicin-induced myocardial toxicity in rats.

OBJECTIVE: To investigate the preventive and curative role of ascorbic acid on doxorubicin (dox)-induced myocardial toxicity in rats. MATERIALS AND METHODS: Animals were divided into five groups of six animals each. Group I served as normal control and received saline 5 ml/kg/day intraperitoneal (i.p.) for a period of 15 days. Group II animals received ascorbic acid 20 mg/kg per oral (p.o.) for 15 days as a pretreatment control (PR). Group III animals received dox 2.5 mg/kg body weight (b.w.), i.p., in six equal injections for two weeks for a total cumulative dose of 15 mg/kg b.w. Group IV animals received ascorbic acid 20 mg/kg p.o. for 15 days as a pretreatment followed by dox 2.5 mg/kg b.w., i.p., in six equal injections for two weeks for a total cumulative dose of 15 mg/kg body weight. Group V animals received dox 2.5 mg/kg b.w., i.p., in six equal injections for two weeks for a total cumulative dose of 15 mg/kg b.w. followed by ascorbic acid 20 mg/kg p.o for 15 days as post-treatment control (CR). The biochemical parameters such as tissue glutathione (GSH), malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD), and enzyme biomarkers such as creatine phosphokinase (CPK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were monitored. RESULTS: Pretreatment with ascorbic acid (20 mg/kg p.o.) significantly protected the myocardium from the toxic effect of dox (PR), by increasing the levels of antioxidant enzymes such as GSH, SOD, and CAT toward normal and decreased the levels of MDA, CPK, LDH, AST, and ALT as compared with dox-treated rats. Post-treatment with ascorbic acid to dox-treated group (CR) significantly increased the levels of tissue GSH, SOD, CAT and significantly decreased the level of MDA as compared with dox-treated group. It also reduced the severity of cellular damage of the myocardium as confirmed by histopathology. The restoration of the endogenous antioxidant system clearly depicts that ascorbic acid produced its protective effect by scavenging the reactive oxygen species. CONCLUSION: The results obtained in this study provide evidence for the usefulness of the ascorbic acid as a cardioprotective agent.

Alcoholic leaf extract of Plectranthus amboinicus regulates carbohydrate metabolism in alloxan-induced diabetic rats.

OBJECTIVE: The present investigation was undertaken to explore the possible mechanisms of Plectranthus amboinicus leaf extract in alloxan-induced diabetic rats. MATERIALS AND METHODS: Control and alloxan-induced diabetic albino rats received different treatments; orally control (vehicle), 200 mg/kg and 400 mg/kg of ethanol extract of Plectranthus amboinicus (PAEE) and 600 µg/kg of glibenclamide (standard) for 15 days. At the end of the experiment, the animals were sacrificed and enzyme activities of carbohydrate metabolism were measured in the liver. RESULTS: Diabetic control rats showed a significant elevation (P < 0.001) in fasting blood glucose on successive days of the experiment as compared with their basal values, which was maintained over a period of 2 weeks. Daily oral treatment with PAEE showed a significant reduction (P < 0.001) in the blood glucose levels on successive days of the experiment as compared with their basal values. The most pronounced antihyperglycemic effect was obtained with the dose of 400 mg/kg. PAEE shows a dose-dependent reduction in gluconeogenic enzymes like glucose-6-phosphatase and fructose-1,6-disphosphatase. After 15 days of treatment with PAEE, glycolytic enzymes like phosphoglucoisomerase resulted in a significant increase with a concomitant significant decrease in the activities of aldolase. On the other hand, glucose-6-phosphate dehydrogenase was significantly improved in diabetic rats on administration of PAEE; the 400 mg/kg dose of PAEE elicited a more potent effect compared with the 200 mg/kg dose. CONCLUSION: The results obtained in this study provide evidence of the antidiabetic activity of PAEE, mediated through the regulation of carbohydrate metabolic enzyme activities.

Protective role of Phyllantus niruri extract in doxorubicin-induced myocardial toxicity in rats.

OBJECTIVES: To investigate the effect of the aqueous extract of Phyllanthus niruri (Aq.E.PN) against doxorubicin (Dox)-induced myocardial toxicity in rats. MATERIALS AND METHODS: Cardiotoxicity was produced by Dox administration (15 mg/kg for 2 weeks). Aq.E PN (200 mg/kg, orally) was administered as pretreatment for 2 weeks alternated with Dox for the next 2 weeks. The general observations, mortality, histopathology, biomarker enzymes like lactate dehydrogenase (LDH), creatinine phosphokinase (CPK) and alkaline phosphatase, diagnostic enzyme markers like aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and antioxidants such as glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) were monitored after 3 weeks of the last dose. RESULTS: Pretreatment with the Aq.E.PN significantly (P < 0.01) protected the myocardium from the toxic effects of Dox by reducing the elevated level of biomarker and diagnostic enzymes like LDH, CPK, AST and ALT to the normal levels. Aq.E PN increased the GSH, SOD and CAT levels and decreased the MDA levels in cardiac tissue. Administration of Dox caused cardiomyopathy associated with an antioxidant deficiency. CONCLUSION: These results suggest a cardioprotective effect of P. niruri due to its antioxidant properties.

Antihyperglycemic and antihyperlipidemic activity of plectranthus amboinicus on normal and alloxan-induced diabetic rats.

The present study was undertaken to investigate the antihyperglycemic and antihyperlipidemic effects of ethanol extract of Plectranthus amboinicus in normal and alloxan-induced diabetic rats. Diabetes was induced in Wistar rats by single intraperitoneal administration of alloxan monohydrate (150 mg/kg). Normal as well as diabetic rats were divided into groups (n=6) receiving different treatments. Graded doses (200 mg/kg and 400 mg/kg) of ethanol extract of Plectranthus amboinicus were studied in both normal and alloxan-induced diabetic rats for a period of 15 days. Glibenclamide (600 µg/kg) was used as a reference drug. Oral administration with graded doses of ethanol extract of Plectranthus amboinicus exhibited hypoglycemic effect in normal rats and significantly reduced the peak glucose levels after 120 min of glucose loading. In alloxan-induced diabetic rats, the daily oral treatment with ethanol extract of Plectranthus amboinicus showed a significant reduction in blood glucose. Besides, administration of ethanol extract of Plectranthus amboinicus for 15 days significantly decreased serum contents of total cholesterol, triglycerides whereas HDL-cholesterol, total proteins and calcium were effectively increased. Furthermore, effect of ethanol extract of Plectranthus amboinicus showed profound elevation of serum amylase and reduction of serum lipase. Histology examination showed ethanol extract of Plectranthus amboinicus exhibited almost normalization of damaged pancreatic architecture in rats with diabetes mellitus. Studies clearly demonstrated that ethanol extract of Plectranthus amboinicus leaves possesses hypoglycemic and antihyperlipidemic effects mediated through the restoration of the functions of pancreatic tissues and insulinotropic effect.

Influence of proton pump inhibitors on dexamethasone-induced gastric mucosal damage in rats.

The present study was designed to compare the curative role of proton pump inhibitors, omeprazole, rabeprazole and lansoprazole against dexamethasone-induced ulcer model. Dexamethasone (5 mg/kg/day) was used as an ulcerogen. Dexamethasone suspended in 1% CMC in water was given orally to all rats. Omeprazole (20 mg/kg), rabeprazole (20 mg/kg), and lansoprazole (20 mg/kg) were administered by oral route 30 minutes prior to dexamethasone for ulcer protective studies, gastric secretion and mucosal studies. Effects of proton pump inhibitors were determined by the evaluation of various biochemical parameters such as estimation of myeloperoxidase, cortisol, alkaline phosphatase, malondialdehyde, endogenous anti-oxidants like superoxide dismutase, catalase and reduced glutathione. In dexamethasone induced ulcer model, omeprazole showed significant decrease in malondialdehyde, myeloperoxidase, alkaline phosphatase level and increase in superoxide dismutase, catalase and reduced glutathione level as compared to rabeprazole and lansoprazole. Omeprazole showed significant reduction in cortisol content where as rabeprazole and lansoprazole did not show significant changes as compared to control. The result indicates that omeprazole is the most effective and selective proton pump inhibitor in dexamethasone induced ulcer model as compared to rabeprazole and lansoprazole.

Comparative study of proton pump inhibitors on dexamethasone plus pylorus ligation induced ulcer model in rats.

The present study was designed to compare ulcer protective effect of proton pump inhibitors viz. omeprazole, rabeprazole and lansoprazole against dexamethasone plus pylorus ligation induced ulcer model. Dexamethasone (5 mg/kg) was used as an ulcerogen. Dexamethasone suspended in 1% CMC in water was given orally to all the rats 15 min after the pylorus ligation. Omeprazole (20 mg/kg), rabeprazole (20 mg/kg), and lansoprazole (20 mg/kg) were administered by oral route 30 min prior to ligation was used for ulcer protective studies, gastric secretion and mucosal studies. Effects of proton pump inhibitors were determined by the evaluation of various biochemical parameters such as ulcer index, free and total acidity, gastric pH, mucin, pepsin and total proteins. Oral administration of proton pump inhibitors showed significant reduction in gastric acid secretion and ulcer protective activity against dexamethasone plus pylorus ligation induced ulcer model. The % protection of omeprazole, rabeprazole and lansoprazole was 84.04, 89.36 and 79.78, respectively. Rabeprazole significantly inhibited the acid-pepsin secretion and increased the gastric mucin secretion. The observations made in the present study suggest that rabeprazole is the most effective gastric antisecretory and ulcer healing agent as compared to omeprazole and lansoprazole.

Evaluation of hepatoprotective activity of Cissus quadrangularis stem extract against isoniazid-induced liver damage in rats.

OBJECTIVE: The study was designed to investigate the hepatoprotective activity of methanol extract of Cissus quadrangularis (CQ) against isoniazid-induced hepatotoxicity in rats. MATERIALS AND METHODS: The successive petroleum ether (60-80°C) and methanol extracts of C. quadrangularis were used. Hepatic damage was induced in Wistar rats by administering isoniazid (54 mg/kg, p.o.) once daily for 30 days. Simultaneously, CQ (500 mg/kg p.o) was administered 1 h prior to the administration of isoniazid (54 mg/kg, p.o.) once daily for 30 days. Silymarin (50 mg/kg p.o) was used as a reference drug. RESULTS: Elevated levels of aspartate transaminase, alanine transaminase, alkaline posphatase, and bilirubin following isoniazid administration were significantly lowered due to pretreatment with CQ. Isoniazid administration significantly increased lipid peroxidation (LPO) and decreased antioxidant activities such as reduced glutathione, superoxide dismutase, and catalase. Pretreatment of rats with CQ significantly decreased LPO and increased the antioxidant activities. CONCLUSION: The results of this study indicated that the hepatoprotective effect of CQ might be attributed to its antioxidant property.

Antiinflammatory, Analgesic and Antipyretic Activities of Mimusops elengi Linn.

In the present study, 70% ethanol extract of Mimusops elengi Linn. bark was assessed for antiinflammatory, analgesic and antipyretic activities in animals. The antiinflammatory activity of ethanol extract of Mimusops elengi (200 mg/kg, p.o) was evaluated using carrageenan-induced paw edema and cotton pellet-induced granuloma models. Analgesic effect was evaluated using acetic acid-induced writhing and Eddy's hot plate models and antipyretic activity was assessed by Brewer's yeast-induced pyrexia in rats. The ethanol extract of Mimusops elengi (200 mg/kg, p.o) significantly inhibited the carrageenan-induced paw oedema at 3rd and 4th h and in cotton pellet model it reduced the transudative weight and little extent of granuloma weight. In analgesic models the ethanol extract of Mimusops elengi decreases the acetic acid-induced writhing and it also reduces the rectal temperature in Brewer's yeast induced pyrexia. However, Mimusops elengi did not increase the latency time in the hot plate test. These results show that ethanol extract of Mimusops elengi has an antiinflammatory, analgesic and antipyretic activity.

Evaluation of Antiinflammatory Activity of Centratherum anthelminticum (L) Kuntze Seed.

In the present study petroleum ether and alcoholic extracts of Centratherum anthelminticum (L) Kuntze seed (100 mg and 200 mg/kg p.o.) were evaluated for antiinflammatory activity in acute and subacute models of inflammation. It was found that both petroleum ether and alcoholic extracts showed significant reduction in paw oedema in carrageenan-induced model. In subchronic inflammatory phase both extracts provoked a significant reduction of transudation phase and too little extent proliferative phase when tested in cotton pellet-induced granuloma model. Both the extracts also reduced alkaline phosphatase activity in serum. The histopathology of granuloma tissue showed significant inhibition of lymphocytes, neutrophils, exudates, necrosis and giant cell when compared with control without ulcerogenic effect. The results suggest that petroleum ether and alcoholic extracts may exert antiinflammatory activity through prostaglandin inhibition, reduced myeloperoxidase and antitransudation.

Cardioprotective effect of lipistat against doxorubicin induced myocardial toxicity in albino rats.

Preventive role of lipistat against doxorubicin induced myocardial toxicity in rats has been reported. Cardiotoxicity was produced by doxorubicin administration (15 mg/kg for 2 weeks). Lipistat (350 mg/kg, orally) was administered as pretreatment for 2 weeks and then for 2 weeks alternated with doxorubicin. The general observations, mortality, histopathology, biomarker enzymes like lactate dehydrogenase (LDH) and creatine phosphokinase (CPK), serum lipid profiles like total cholesterol, triglycerides, low-density lipoprotein (LDL) and high-density lipoprotein (HDL), antioxidant enzymes such as glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were monitored after 3 weeks of last dose. Pretreatment with the lipistat significantly protected myocardium from the toxic effects of doxorubicin by reducing the elevated level of biomarker enzymes like LDH and CPK to the normal and serum lipids such as total cholesterol, triglyceride and LDL back to normal. Lipistat increases the decreased level of GSH, SOD and CAT and decreases the increased level of malondialdehyde in cardiac tissue. The repeated administration of doxorubicin causes cardiomyopathy associated with an antioxidant deficit and increased level of lipid profiles by interfering with fatty acid metabolism. The results support the lipid lowering and antioxidant properties of lipistat, which indicate the cardioprotective property against doxorubicin induced cardiotoxicity.

Synthesis and pharmacological evaluation of a novel series of 5-(substituted)aryl-3-(3-coumarinyl)-1-phenyl-2-pyrazolines as novel anti-inflammatory and analgesic agents.

A novel series of 5-(substituted)aryl-3-(3-coumarinyl)-1-phenyl-2-pyrazolines (3a-l) were synthesized by reacting various substituted 3-aryl-1-(3-coumarinyl)propan-1-ones (2a-l) with phenylhydrazine in the presence of hot pyridine. Structures of all new synthesized compounds were characterized on the basis of elemental analysis and spectral data (IR, (1)H NMR and (13)C NMR). The title compounds were screened for in vivo anti-inflammatory and analgesic activities at a dose of 200 mg/kg b.w. Among the 12 prepared compounds, Compounds 3d, e, i and j exhibited significant anti-inflammatory activity in model of acute inflammation such as carrageenan-induced rat edema paw while compounds 3d and e showed considerable activity in model of chronic inflammation such as adjuvant-induced arthritis and were compared with diclofenac (13.5 mg/kg b.w.) as a standard drug. These compounds were also found to have significant analgesic activity in the acetic acid induced writhing model and antipyretic activity in yeast-induced pyrexia model along with minimum ulcerogenic index.

Evaluation of Analgesic and Antipyretic Activities of Centratherum anthelminticum (L) Kuntze Seed.

The study was designed to investigate analgesic and antipyretic activities of petroleum ether and alcohol extracts of Centratherum anthelminticum (L) Kuntze (family: Asteraceae) seeds (100 and 200 mg/kg, p.o.) in brewer's yeast-induced fever model in rats, acetic acid-induced writhing and Eddy's hot plate methods in mice. Both petroleum ether and alcohol extracts showed significant decrease in number of writhes in acetic acid-induced writhing and increase in paw licking time to heat stimuli in the hot plate method. The maximum analgesic activity was observed at 90 min after dosing when compared to control. Both the extracts showed significant inhibition of elevated body temperature when compared to corresponding control. These results suggested that the petroleum ether and alcohol extracts possessed analgesic and antipyretic activities.