Histamine mediates the pro-inflammatory effect of latex of Calotropis procera in rats. (1/28)

INTRODUCTION: Calotropis procera is known to produce contact dermatitis and the latex of this plant produces intense inflammation when injected locally. However, the precise mode of its pro-inflammatory effect is not known. In present study we have pharmacologically characterized the inflammation induced by latex of C. procera in a rat paw edema model and determined the role of histamine in latex-induced inflammation. METHODS: Inflammation was induced in the hind paw of rats by injecting different doses of dried latex (DL) of C. procera. The inhibitory effect of phenylbutazone, dexamethasone, celecoxib, cyproheptadine, chlorpheniramine and compound 48/80 on edema volume was evaluated and compared with that against carrageenan. The histamine content of DL was measured fluorometrically. RESULTS: DL produced dose-dependent inflammation of the rat paw. Cyproheptadine and chlorpheniramine effectively inhibited DL-induced inflammation (90%; p < 0.01), while anti-inflammatory drugs phenylbutazone, dexamethasone and celecoxib were more effective against carrageenan-induced inflammation. Depletion of mast cell histamine by compound 48/80 produced a significant decrease in DL-induced inflammation as compared with carrageenan (500% versus 25%). DL was also found to contain about 6 microg/g of histamine. CONCLUSIONS: Thus, our study shows that the biogenic amines play a significant role in C. procera latex-induced inflammation and antihistaminic drugs could be effectively used to inhibit inflammatory response elicited by exposure to latex.  (+info)

Studies on anti-diarrhoeal activity of Calotropis gigantea R.Br. in experimental animals. (2/28)

PURPOSE: Calotropis gigantea R. Br. (Asclepiadaceae) a wildly growing plant has been reported to possess number of medicinal properties and other purposes. The purpose of the present study was to evaluate scientifically the anti-diarrheal effects of C. gigantea used traditionally in Indian system of medicine using castor oil-induced diarrhoea model. METHODS: The anti-diarrheal effect of hydroalcoholic (50:50) extract of aerial part of Calotropis gigantea was studied against castor oil-induced-diarrhea model in rats. The gastrointestinal transit rate was expressed as the percentage of the longest distance traversed by the charcoal divided by the total length of the small intestine. The weight and volume of intestinal content induced by castor oil were studied by enteropooling method. RESULTS: Like atropine (3 mg/kg, i.p.) there were significant reductions in fecal out put and frequency of droppings when the plant extracts of 200 and 400 mg/kg doses were administered intraperitoneally compared with castor oil treated rats. All doses of the plant extracts also significantly retarded the castor-oil induced enteropooling and intestinal transit. The dose 100 (P<0.01), 200 and 400 mg/kg significantly inhibited (P<0.001) weight and volume of intestinal content. CONCLUSIONS: The remarkable anti-diarrheal effect of C.gigantea extract against castor oil-induced diarrhea model attests to its utility in a wide range of diarrheal states  (+info)

Involvement of prostaglandins in inflammation induced by latex of Calotropis procera. (3/28)

INTRODUCTION: The aerial parts of the plant Calotropis procera produce milky white latex that causes inflammation of the skin and mucous membranes. Prostaglandins are one of the mediators released in an inflammatory response following induction of cyclooxygenase (COX). In the present study, we have evaluated the role of prostaglandins in inflammatory response elicited by the latex of C. procera. METHODS: Aqueous extract of dried latex of C. procera was injected into the 6-day air-pouch in the rat. The inflammatory response was evaluated by studying the air-pouch fluid for its volume, protein and prostaglandin (PG) E2 concentrations, and leucocyte counts. The granulation tissue from the pouch was quantified and studied for COX-2 expression by reverse transcriptase-polymerase chain reaction. The inhibitory effect of celecoxib and dexamethasone was evaluated on the aforementioned parameters. RESULTS: Dried latex produced an inflammatory response that was maximum at 6 h. It was associated with the accumulation of protein-rich fluid, leucocytes and PGE2 production. It also resulted in granulation of the pouch cavity that was a maximum on day 3. COX-2 expression could be detected in the granulation tissue on day 1 and it increased progressively up to day 5. The anti-inflammatory drugs celecoxib and dexamethasone significantly attenuated the inflammatory response and inhibited COX-2 expression in granulation tissue. CONCLUSIONS: Latex of C. procera induces an inflammatory response characterized by an early exudative phase accompanied by PGE2 production and a late proliferative phase associated with COX-2 induction. Both the phases were effectively inhibited by COX-2 inhibitors.  (+info)

Calotropis procera latex-induced inflammatory hyperalgesia--effect of antiinflammatory drugs. (4/28)

The milky white latex of plant Calotropis procera produces inflammation of the skin and mucous membranes on accidental exposure. It produces edema on local administration due to the release of histamine and prostaglandins and is associated with hyperalgesia. In the present study we have evaluated the antiedematous and analgesic activity of antiinflammatory drugs against inflammatory response induced by dried latex (DL) of C procera in rat paw edema model. An aqueous extract of DL of C procera was injected into the subplantar surface of the rat paw and the paw volume was measured by a plethysmometer at 0, 1, 2, 6, 12, and 24 hours. Concomitantly the hyperalgesic response was also evaluated by motility test, stair climbing ability test, dorsal flexion pain test, compression test, and observing the grooming behavior. The inhibitory effect of diclofenac and rofecoxib on edema formation and hyperalgesic response was compared with cyproheptadine (CPH). DL-induced edema formation was maximum at 2 hours that was associated with decreased pain threshold, functional impairment, and grooming. Treatment with antiinflammatory drugs and CPH significantly attenuated the edematous response and grooming, increased the pain threshold, and improved functional parameters. Both antiinflammatory and antiserotonergic drugs significantly inhibited the hyperalgesia associated with DL-induced paw edema. Rofecoxib was found to be superior than diclofenac and was as effective as CPH in ameliorating the hyperalgesia. However, it was found to be less effective than CPH in attenuating edema formation.  (+info)

Antiinflammatory efficacy of extracts of latex of Calotropis procera against different mediators of inflammation. (5/28)

The latex of the plant Calotropis procera has been reported to exhibit potent antiinflammatory activity against carrageenin and formalin that are known to release various mediators. In the present study, we have evaluated the efficacy of extracts prepared from the latex of C procera against inflammation induced by histamine, serotonin, compound 48/80, bradykinin (BK), and prostaglandin E2 (PGE2) in the rat paw oedema model. The paw oedema was induced by the subplantar injection of various inflammagens and oedema volume was recorded using a plethysmometer. The aqueous and methanol extracts of the dried latex (DL) and standard antiinflammatory drugs were administered orally 1 hour before inducing inflammation. The inhibitory effect of the extracts was also evaluated against cellular influx induced by carrageenin. The antiinflammatory effect of aqueous and methanolic extracts of DL was more pronounced than phenylbutazone (PBZ) against carrageenin while it was comparable to chlorpheniramine and PBZ against histamine and PGE2, respectively. Both extracts produced about 80%, 40%, and 30% inhibition of inflammation induced by BK, compound 48/80, and serotonin. The histological analysis revealed that the extracts were more potent than PBZ in inhibiting cellular infiltration and subcutaneous oedema induced by carrageenin. The extracts of DL exert their antiinflammatory effects mainly by inhibiting histamine and BK and partly by inhibiting PGE2.  (+info)

Inhibition of Calotropis procera latex-induced inflammatory hyperalgesia by oxytocin and melatonin. (6/28)

The latex of the wild growing plant Calotropis procera produces inflammation of the skin and mucous membranes upon accidental exposure. On local administration it elicits an intense inflammatory response due to the release of histamine and prostaglandins that is associated with hyperalgesia. In the present study we have evaluated the anti-inflammatory and antinociceptive activity of oxytocin and melatonin against rat paw edema induced by dried latex (DL) of C procera and compared it with that against carrageenan-induced paw edema. Aqueous extract of DL of C procera or carrageenan (1%) was injected into the subplantar surface of the rat paw and the paw volume was measured at 0, 1, 2, 3, 4, 6, 10, and 24 hours. The associated hyperalgesic response and functional impairment were also evaluated concomitantly by dorsal flexion pain test, motility test, and stair climbing ability test. The inhibitory effect of oxytocin and melatonin on edema formation and hyperalgesic response was compared with dexamethasone. DL-induced edema formation was maximum at 2 hours and was associated with decreased pain threshold and functional impairment. Treatment with melatonin significantly attenuated the edematous response while both oxytocin and melatonin increased the pain threshold and improved functional parameters. Both oxytocin and melatonin significantly inhibited the hyperalgesia associated with DL-induced paw edema. Oxytocin was found to be as effective as melatonin in ameliorating the hyperalgesic response. However, it was found to be less effective than melatonin in attenuating edema formation.  (+info)

Anticancer and cytotoxic properties of the latex of Calotropis procera in a transgenic mouse model of hepatocellular carcinoma. (7/28)

AIM: To evaluate the anticancer property of the dried latex (DL) of Calotropis procera, a tropical medicinal plant, in the X15-myc transgenic mouse model of hepatocellular carcinoma and to elucidate its mechanism of action in cell culture. METHODS: The young transgenic mice were orally fed with the aqueous suspension of DL (400 mg/kg for 5 d/wk) for 15 wk and their liver was examined for histopathological changes at 20 wk. Serum levels of vascular endothelial growth factor (VEGF) were also measured in these animals. To characterize the active fraction, DL was extracted with petroleum ether followed by methanol. The methanolic extract was sub-fractionated on a silica gel G column using a combination of non-polar and polar solvents and eleven fractions were obtained. Each fraction was analysed for cytotoxic effect on hepatoma (Huh7) and non-hepatoma (COS-1) cell lines and non-transformed hepatocytes (AML12) using tetrazolium (MTT) assay. Finally, the mechanism of cell death was investigated by measuring the levels of Bcl2, caspase 3 and DNA fragmentation. RESULTS: DL treatment of mice showed a complete protection against hepatocarcinogenesis. No adverse effect was observed in these animals. The serum VEGF level was significantly lowered in the treated mice as compared to control animals. Cell culture studies revealed that the methanolic extract of DL as well as its fraction 8 induced extensive cell death in both Huh-7 and COS-1 cells while AML12 cells were spared. This was accompanied by extensive fragmentation of DNA in Huh-7 and COS-1 cells. No change in the levels of canonical markers of apoptosis such as Bcl2 and caspase 3 was observed. CONCLUSION: DL of C. procera has the potential for anti-cancer therapy due to its differentiable targets and non-interference with regular pathway of apoptosis.  (+info)

Latex constituents from Calotropis procera (R. Br.) display toxicity upon egg hatching and larvae of Aedes aegypti (Linn.). (8/28)

Calotropis procera R. Br. (Asclepiadaceae) is a well-known medicinal plant with leaves, roots, and bark being exploited by popular medicine to fight many human and animal diseases. This work deals with the fractionation of the crude latex produced by the green parts of the plant and aims to evaluate its toxic effects upon egg hatching and larval development of Aedes aegypti. The whole latex was shown to cause 100% mortality of 3rd instars within 5 min. It was fractionated into water-soluble dialyzable (DF) and non-dialyzable (NDF) rubber-free materials. Both fractions were partially effective to prevent egg hatching and most of individuals growing under experimental conditions died before reaching 2nd instars or stayed in 1st instars. Besides, the fractions were very toxic to 3rd instars causing 100% mortality within 24 h. When both fractions were submitted to heat-treatment the toxic effects were diminished considerably suggesting low thermostability of the toxic compounds. Polyacrylamide gel electrophoresis of both fractions and their newly fractionated peaks obtained through ion exchange chromatography or desalting attested the presence of proteins in both materials. When submitted to protease digestion prior to larvicidal assays NDF lost most of its toxicity but DF was still strongly active. It may be possible that the highly toxic effects of the whole latex from C. procera upon egg hatching and larvae development should be at least in part due to its protein content found in NDE However the toxicity seems also to involve non protein molecules present in DF.  (+info)

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