Anti-hyperglycemic and anti-hyperlipidemic effects of rhinacanthins-rich extract from Rhinacanthus nasutus leaves in nicotinamide-streptozotocin induced diabetic rats.

Rhinacanthus nasutus has traditionally been used in the treatment of various disorders including diabetes mellitus. Rhinacanthins-rich extract (RRE) is a semipurified R. nasutus leaf extract that contains 60% w/w of rhinacanthin-C (RC) obtained by a green extraction process. The purpose of this study was to investigate the anti-hyperglycemic and anti-hyperlipidemic activity of RRE (15 mg/kg equivalent to RC content) in comparison to its marker compound RC (15 mg/kg) and the standard drug glibenclamide (Glb) (600 µg/kg) in nicotinamide-streptozotocin induced diabetic rats for 28 days. In addition, the in silico pharmacokinetic and toxicity analysis of RC was also performed. RRE, RC and Glb significantly reduced the FBG, HbA1c and food/water intake while increasing the insulin level and body weight in diabetic rats without affecting the normal rats. The serum lipid, liver and kidney biomarkers were markedly normalized by RRE, RC and Glb in diabetic rats without affecting the normal rats. Moreover, the histopathology of the pancreas revealed that RRE, RC and Glb evidently restored the islets of Langerhans in diabetic rats. The overall results indicated that RRE has equivalent antidiabetic potential to that of RC. Moreover, the in silico pharmacokinetic and toxicity analysis predicts that RC is orally non-toxic, non-carcinogenic and non-mutagenic with a decent bioavailability. The undertaken study suggests that RRE could be used as an effective natural remedy in the treatment of diabetes.

Physicochemical properties, in vitro release and skin permeation studies of a topical formulation of standardized pomegranate rind extract.

The aim of the present study was to develop a stable formulation containing standardized pomegranate rind extracts (SPRE) for topical use in the treatment of dermal diseases. Ellagic acid (EA) as the major active constituent of SPRE (not less than 13%) was quantified by HPLC as an indicator for studies on the stability, in vitro drug release, and skin penetration/retention. The formulation prepared with polyethylene glycols (PEG 400 and PEG 4000) containing 5% SPRE has been found to be stable and provide a release rate of 36.6741±5.0072 µg/cm(2)/h that was best fitted to the zero-order kinetic model. EA from SPRE did not penetrate the full-thickness rat skin but the skin retention of EA was determined to be 2.22±0.16 µg/cm(2) with a total recovery of 95.14±5.51%. The results indicated that this 5% SPRE PEG ointment was of satisfactory physicochemical properties and worth further in vivo investigations.

Wound healing activities of standardized pomegranate rind extract and its major antioxidant ellagic acid in rat dermal wounds.

The in vivo wound healing potential of a standardized pomegranate rind extract (SPRE) and its major antioxidant constituent, ellagic acid (EA, 13 %, w/w), were investigated in three rat dermal wound models. It was found that both SPRE (5 and 2.5 %) and its equivalent amount of EA (0.65 and 0.325 %) increased the tensile strength of the incision wound by a maximum of 35.43 and 31.82 %, respectively. SPRE at 5 and 2.5 % accelerated wound contraction of the excision wound and the burn wound, while EA was effective only at 0.65 % in these two wound models. Further assays revealed that SPRE enhanced the synthesis of collagen by a maximum of 21.83 mg/g and inhibited neutrophil infiltration dose-dependently, while EA was not effective in increasing collagen accumulation and its inhibitory effect on neutrophil infiltration was milder. These results indicated that SPRE is a promising phytopharmaceutical effective in facilitating the healing of wounds and is superior to its marker compound EA.

Topical anti-inflammatory potential of standardized pomegranate rind extract and ellagic acid in contact dermatitis.

The present study evaluated the topical anti-inflammatory potential of a standardized pomegranate rind extracts (SPRE) in parallel with its marker compound ellagic acid (EA, 13% w/w) against a mouse model of contact dermatitis. In the phenol-induced mouse ear edema, topical application of SPRE (5, 2.5, and 1 mg/ear) and EA (0.65, 0.325, and 0.13 mg/ear, equivalent to its content in SPRE) dose-dependently reduced the ear edema with the maximal inhibition of 79.12% and 73.63%, respectively. Triamcinolone (0.1 mg/ear) and diclofenac (1 mg/ear) as reference drugs inhibited the edema by 73.63% and 37.91%. Myeloperoxidase (MPO) activity in the mouse ear was also decreased by SPRE and EA up to 69.68% and 68.79%, respectively. Triamcinolone and diclofenac decreased the MPO activity by 76.66% and 80.14% similarly. The results indicated that topical application of SPRE and EA is promising for use in the treatment of inflammatory skin disorders.

Topical anti-inflammatory and analgesic activities of standardized pomegranate rind extract in comparison with its marker compound ellagic acid in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: In Chinese traditional medicine, the peels of Punica granatum L. have been used to treat traumatic hemorrhage, burn, and ulcers. AIMS OF THE STUDY: This study aimed to assess the topical anti-inflammatory and analgesic activities of a standardized pomegranate rind extract (SPRE) of which ellagic acid (EA) was the major antioxidant constituent and the marker compound. MATERIAL AND METHODS: The topical anti-inflammatory effects of SPRE were evaluated against acute models (croton oil-induced mouse ear edema and carrageenan-induced rat paw edema) and chronic model (complete Freund's adjuvant (CFA)-induced polyarthritis). The topical analgesic activities of SPRE were investigated in the rat punctuate mechanical hyperalgesia test and in the mouse formalin test. All studies of SPRE were carried out in parallel with its marker compound EA. RESULTS: SPRE (5%, 2.5%, and 1%, w/w) and the equivalent EA (0.65%, 0.325%, and 0.13%, w/w) dose-dependently reduced the croton oil-induced mouse ear edema with a maximal inhibition of 86.30% and 80.82%, respectively. SPRE dose-dependently attenuated the inflammatory responses in the carrageenan-induced rat paw edema and in the CFA-induced polyarthritis but the equivalent EA were effective only at the doses of 0.65% and 0.325%. Both SPRE (5%) and EA (0.65%) showed significant topical analgesic activities in the rat punctuate mechanical hyperalgesia test and in the mouse formalin test. CONCLUSIONS: SPRE was more active as an anti-inflammatory agent than EA. The anti-inflammatory and analgesic effects of SPRE were achieved through inhibiting the leukocyte infiltration and modulating the pro-inflammatory cytokines IL-ß and TNF-α. These results clearly demonstrated that SPRE is a promising phytomedicine that could find use in the treatment of inflammatory diseases.

Incidence and risk for neutropenia/agranulocytosis among clozapine users: A retrospective cohort study.

Abstract Objective. To estimate the incidence and the risk of neutropenia or agranulocytosis (the outcome) associated with clozapine use (the exposure), and to identify risk factors. Methods. All data were derived from the computerized hospital database. Adult psychiatric patients were identified, and 95 incident clozapine users and 884 non-clozapine users were included. Cox proportional hazards regression was used to estimate the hazards ratio (HR) of developing the outcome after clozapine use adjusted for confounders. The interaction between clozapine and valproic acid was assessed a posteriori. Results. Throughout the 24-month follow-up, the incidence of neutropenia was 6.3% in the clozapine group and 5.8% in the non-clozapine group. One agranulocytosis was found in the non-clozapine group. The HR (95% CI) for neutropenia were: clozapine 1.33 (0.54-3.25) and age . 45 years 2.99 (1.63-5.48). Lithium, as an independent protective factor, reduced the risk for neutropenia by 85% compared with patients who did not receive lithium, HR 0.15 (95% CI 0.02-1.09). Valproic acid might potentiate the clozapine-associated neutropenia (HR 5.10, 95% CI 0.70-37.12). Conclusion. Clozapine might slightly increase the risk of neutropenia in psychiatric patients. Concerning clozapine-associated neutropenia, older patients are at increased risk and use of valproic acid concurrently with clozapine should be avoided.

Evaluation of the analgesic and anti-inflammatory activities of Curcuma mangga Val and Zijp rhizomes.

The effects of Curcuma mangga ethanolic extract (CME) and its fractions, e.g., aqueous, chloroform, ethyl acetate, and hexane fractions, from C. mangga rhizome were investigated on nociceptive responses using writhing, hot plate, and formalin tests in mice and inflammatory models using carrageenan-induced rat paw edema and croton oil-induced mouse ear edema. The results showed that CME and all fractions (200 mg/kg, p.o.) significantly reduced the number of writhings. Oral administration (p.o.) of CME, chloroform, and hexane fractions (200 mg/kg) significantly prolonged the latency time, whereas aqueous and ethyl acetate fractions were inactive. The activities of CME, chloroform, and hexane fractions were abolished by naloxone (2 mg/kg, intraperitoneal (i.p.)). CME and all fractions at the dose of 200 mg/kg significantly produced antinociception in both early and late phases of the formalin test. CME, chloroform, and hexane fractions were more prominent in licking inhibition than those of the aqueous and ethyl acetate fractions. CME and all fractions (150 mg/kg, p.o.) showed significant reduction of rat paw edema. The order of activity on inhibition of paw edema at 4 h was chloroform fraction > hexane fraction > ethyl acetate fraction > CME > aqueous fraction. When topically applied at 0.5 mg/ear, CME and all fractions suppressed ear edema induced by croton oil. CME and chloroform fraction showed a greater inhibition by 53.97 and 50.29%, respectively. These results suggested that CME and its fractions, especially chloroform and hexane fractions from C. mangga rhizome, possessed centrally acting analgesic as well as anti-inflammatory activities.

Antinociceptive, antipyretic, and anti-inflammatory activities of Putranjiva roxburghii Wall. leaf extract in experimental animals.

The effects of the ether extract from the leaves of Putranjiva roxburghii (P. roxburghii) Wall. were assessed on nociceptive responses in mice by using writhing, hot plate, and formalin tests and the antipyretic activity was determined in yeast-induced fever in rats. Anti-inflammatory activities were also investigated using carrageenin-induced paw edema in rats and croton oil-induced ear and anus edemas. The ether extract (100, 200, and 400 mg/kg, p.o.) of P. roxburghii dose-dependently produced analgesic activity in acetic acid-induced writhing in mice. The extract had no significant effect in the hot plate test in mice. At the dose of 400 mg/kg, the extract significantly suppressed the licking activity in the late phase of the formalin test in mice and decreased fever induced by yeast in rats. The extract exhibited moderate inhibitory activity of inflammation in carrageenin-induced paw edema in rats. The extract inhibited croton oil-induced ear edema in a dose-dependent manner (1.25, 2.5, and 5.0 mg/ear) in mice. The extract decreased anus edema induced by croton oil at the high dose of 800 mg/kg in rats. The results indicated that the ether extract of P. roxburghii leaves possesses analgesic, antipyretic, and anti-inflammatory activities.

Uterine relaxant effects of Curcuma aeruginosa Roxb. rhizome extracts.

The effects and plausible mechanism of action of Curcuma aeruginosa Roxb. (Zingiberaceae) rhizome chloroform and methanol extracts on the uterine contraction were investigated using isolated uterus strips from estrogen primed rats. The contractile responses were recorded isometrically with a Grass FT03 force transducer connected to a MacLab system. The experiments were carried out on both nonstimulated, agonist- and KCl-stimulated uteri. In the nonstimulated uterus, the two extracts (10-400 microg/ml) had no significant effect. In contrast, in the stimulated uterus, the chloroform and methanol extracts exerted concentration-dependent inhibition of the contractions induced by oxytocin (1 mU/ml), prostaglandin F2alpha (PGF2alpha, 0.5 microg/ml), ACh (3x10(-6) M) and KCl (40 mM) with the IC50 (inhibition of force) of 31.4, 58.59, 56.21 and 29.28 microg/ml; and 57.79, 69.3, 223.8 and 69.19 microg/ml, respectively. Verapamil, the reference L-type calcium channel blocker, exhibited a similar pattern of inhibition with the IC50 of 0.03, 0.25, 0.35 and 0.04 microg/ml. The IC50 of diclofenac against a PGF2alpha-induced contraction was 31.36 microg/ml. It is known that the contraction induced by agonists and KCl is mainly due to calcium influx through the voltage-gated L-type calcium channels opened indirectly or directly by agonist-receptor activation and KCl. Thus, it is speculated that the two plant extracts might inhibit uterine contraction by interrupting the influx of Ca2+ probably through voltage-gated L-type calcium channels. This possibility was further substantiated by the ability of the extracts to shift the CaCl2-contraction curves to the right. As the methanol extract also reduced the contraction of oxytocin in Ca2+-free EDTA solution; thus, it is suggested that part of its action may be involved with an intracellular mechanism. The effect of the two extracts did not involve the activation of beta2-adrenoceptors since their effects were unaffected by propranolol. Based on the inhibitory effect of the extracts on the oxytocin-induced contraction, it is concluded that the extracts might be useful as tocolytic agents for the prevention of preterm labor. Their effects on the inhibition of PGF2alpha-induced contractions also seem useful for the treatment of dysmenorrhea. There are reports by others that the plant rhizome contains beta-pinene and sesquiterpenes. In addition, there is evidence that these compounds possess spasmolytic effects in the rat intestine and uterus. Therefore, the uterine relaxant effect of the plant extracts could be due to beta-pinene and some sesquiterpene lactones contents. The methanol extract is less potent than the chloroform extract, and this might be due to the lower amount of terpene compounds or different compounds may involve in this action.

Antinociceptive activity of the methanolic extract of Kaempferia galanga Linn. in experimental animals.

Kaempferia galanga Linn. (Zingiberaceae) presents many chemical constituents of the volatile oil extracted from the rhizome. The rhizome of Kaempferia galanga is used by people in many regions for relieving toothache, abdominal pain, muscular swelling and rheumatism. In this study we investigated the antinociceptive activity in mice and rats using acetic acid-induced writhing, formalin, hot plate and tail-flick tests. The extract at test doses of 50, 100 and 200 mg/kg, p.o. clearly demonstrated antinociceptive activity in all tests. This activity was dose- and time-dependent. The extract administered at 200 mg/kg, p.o. had a stronger antinociceptive effect than aspirin (100 mg/kg, p.o.) but less than morphine (5 mg/kg, s.c.). Naloxone (2 mg/kg, i.p.) abolished the antinociceptive action of both morphine (5 mg/kg, s.c.) and the extract (200 mg/kg, p.o.) in a similar manner. In conclusion, the methanol extract of Kaempferia galanga markedly demonstrated the antinociceptive action in experimental animals. The antinociceptive mechanisms appear to be both peripherally and centrally mediated actions and the opioid receptors are probably involved. Therefore, our studies support the use in traditional medicine of Kaempferia galanga against pain caused by various disorders.

Effects of curcumin on reflux esophagitis in rats.

The preventive effect of curcumin, a compound isolated from the rhizome of Curcuma longa, on experimental reflux esophagitis in rats was investigated in order to validate its potential therapeutic use for gastroesophageal reflux disease. Curcumin (20 mg/kg, i.d.), the antioxidative agent dimethyl sulfoxide (DMSO) (1 ml/kg, i.p.) or the proton pump inhibitor lansoprazole (1 mg/kg, i.d.) inhibited the formation of acute acid reflux esophagitis by 52.5, 61.5 and 70.9% respectively. Curcumin alone was not effective in preventing chronic acid reflux esophagitis, but the combination of curcumin and DMSO reduced the mortality rate and the severity of the esophagitis ulcer index to the same extent (56.5%) as did the lansoprazole (53.9%). Intraduodenal administration of curcumin also markedly prevented the formation of acute mixed reflux esophagitis, together with reducing the incidence or the severity of neutrophil infiltration, when compared to a control group. In contrast, lansoprazole tended to increase the severity of all histopathological changes, when compared to either the control or the curcumin-treated group. Aminoguanidine, a specific inducible nitric oxide synthase inhibitor, had no preventive effect against both types of acute reflux esophagitis models, and increased the mortality in the chronic acid reflux esophagitis model. From these results, it is indicated that curcumin can effectively prevent acute reflux esophagitis formation. Although curcumin is less potent than lansoprazole in inhibiting acid reflux esophagitis, it is superior to lansoprazole in inhibiting mixed reflux esophagitis. The antiulcerogenic mechanisms are considered to be closely associated with its antioxidant nature and antiinflammatory property.

Preventive and curative effects of curcumin on the development of gastric inflammatory diseases in rats.

Preventive and curative effects of curcumin on experimental acute and chronic gastric ulcers were investigated to validate its clinical application on a remedy for peptic ulcer. Intraduodenal administration of curcumin, 5-20 mg/kg, inhibited gastric acid secretion in pylorus-ligated rats, and oral administration prevented ethanol-induced acute gastric mucosal lesions. Curcumin (20-80 mg/kg, p.o.) dose-dependently prevented both serotonin-induced gastric mucosal lesions and compound 48/80-induced gastric mucosal lesions in rats. Furthermore, oral administration of curcumin, 10-80 mg/kg, twice daily for 10 days, significantly accelerated the healing of acetic acid-induced chronic gastric ulcer and promoted mucosal regeneration in the ulcerated portion in a dose-related manner. Cimetidine prevented the formation of ethanol-induced gastric mucosal lesions, but not of serotonin-induced and compound 48/80-induced gastric mucosal lesions. Consecutive administration of cimetidine showed a marked acceleration in the healing of acetic acid-induced ulcer. Aminoguanidine, an inducible nitric oxide synthase (iNOS) inhibitor, showed anti-ulcerogenic effects similar to those oberved for curcumin. The present results indicate that curcumin exhibits gastric cytoprotection in the acute lesion models and ulcer healing promotion in the chronic ulcer model. The preventive and curative effects of curcumin might be due to an increase in the mucosal defensive mechanism through its antioxidant property and inhibition of NO or cytokine-mediated inflammation.