Evaluation of the analgesic, anti-inflammatory and anti-diabetic properties of Sclerocarya birrea (A. Rich.) Hochst. stem-bark aqueous extract in mice and rats

In order to appraise some of the ethnomedical uses of Sclerocarya birrea (A. Rich.) Hochst., subspecies caffra (Sond.) Kokwaro [family: Anacardiaceae], the present study was undertaken to investigate the analgesic, anti-inflammatory and anti-diabetic properties of the plant's stem-bark aqueous extract in experimental models of pain, inflammation and diabetes mellitus. The analgesic effect of Sclerocarya birrea stem-bark aqueous extract was evaluated in mice, while its anti-inflammatory and anti-diabetic effects were investigated in rats. Diclofenac (DIC, 100 mg/kg p. o.) and chlorpropamide (250 mg/kg p. o.) were used respectively as reference analgesic, anti-inflammatory and anti-diabetic agents for comparison. Like diclofenac (DIC, 100 mg/kg p. o.), Sclerocarya birrea stem-bark aqueous extract (SBE, 100-800 mg/kg p. o.) produced dose-dependent, significant protection (p < 0.05-0.001) against electrical heat-induced pain. The plant extract (SBE, 25-800 mg/kg p. o.) also produced dose- and time-related, sustained and significant reductions (p < 0.05-0.001) in the fresh egg albumin-induced acute inflammation of the rat hind paw oedema. However, the analgesic and anti-inflammatory effects of the plant's extract were found to be approximately 10-15 times less than that of diclofenac. In one set of experiments involving hypoglycaemic/antidiabetic evaluation of the plant's extract, graded doses of Sclerocarya birrea stem-bark aqueous extract (SBE, 25-800 mg/kg p. o.) were separately administered to groups of fasted normal and fasted diabetic rats. In another set of experiments, a single dose of the plant's aqueous extract (SBE, 800 mg/kg p. o.) was used. The hypoglycaemic effect of this single dose of Sclerocarya birrea stem-bark aqueous extract (SBE, 800 mg/kg p. o.) was compared with that of chlorpropamide (250 mg/kg p. o.) in both fasted normal and fasted streptozotocin (STZ)-treated diabetic rats. Following acute treatment, relatively moderate to high doses of Sclerocarya birrea stem-bark aqueous extract (SBE, 25-800 mg/kg p. o.) produced dose-dependent, significant reductions (p < 0.05-0.001) in the blood glucose concentrations of both fasted normal and fasted diabetic rats. Chlorpropamide (250 mg/kg p. o.) also produced significant reductions (p < 0.05-0.001) in the blood glucose concentrations of the fasted normal and fasted diabetic rats. Administration of the single dose of Sclerocarya birrea stem-bark aqueous extract (SBE, 800 mg/kg p. o.) significantly reduced (p < 0.01-0.001) the blood glucose levels of both fasted normal (normoglycaemic) and fasted STZ-treated, diabetic rats. The results of this experimental animal study indicate that Sclerocarya birrea stem-bark aqueous extract possesses analgesic, anti-inflammatory and hypoglycaemic properties. These experimental findings lend pharmacological support to the suggested folkloric uses of the plant's stem-bark in the management and/or control of pain, inflammatory conditions, and adult-onset, type-2 diabetes mellitus in some communities of South Africa.     

Antidiarrhoeic activity of Sclerocarya birrea bark extract and its active tannin constituent in rats

The antidiarrhoeic activity of the bark of Sclerocarya birrea was investigated. The lyophilized decoction demonstrated antidiarrhoeic activity in experimental models of diarrhoea induced by magnesium sulphate and sodium picosulphate. This antidiarrhoeic activity was related to an inhibition of intestinal transit rather than to inhibition of net secretion of fluid and electrolytes provoked by the laxative agents. A condensed tannin was isolated from the crude drug which produced inhibition in intestinal motility, and the monomer of which was identified as procyanidin.     

Effect of Sclerocarya birrea (Anacardiaceae) stem bark methylene chloride/methanol extract on streptozotocin-diabetic rats

Sclerocarya birrea (Anacardiaceae) is used as a traditional treatment of diabetes in Cameroon. In this study, we investigated the possible antidiabetic effect of the stem bark extract in diabetic rats. Diabetes was induced by intravenous injection of streptozotocin (STZ, 55 mg/kg) to male Wistar rats. Experimental animals (six per group), were treated by oral administration of plant extract (150 and 300 mg/kg body weight) and metformin (500 mg/kg; reference drug) for comparison, during 21 days. The stem bark methanol/methylene chloride extract of Sclerocarya birrea exhibited at termination, a significant reduction in blood glucose and increased plasma insulin levels in diabetic rats. The extract also prevented body weight loss in diabetic rats. The effective dose of the plant extract (300 mg/kg) tended to reduce plasma cholesterol, triglyceride and urea levels toward the normal levels. Four days after diabetes induction, an oral glucose tolerance test (OGTT) was also performed in experimental diabetic rats. The results showed a significant improvement in glucose tolerance in rats treated with Sclerocarya birrea extract. Metformin, a known antidiabetic drug (500 mg/kg), significantly decreased the integrated area under the glucose curve. These data indicate that Sclerocarya birrea treatment may improve glucose homeostasis in STZ-induced diabetes which could be associated with stimulation of insulin secretion.     

Glucose lowering efficacy of Ficus racemosa bark extract in normal and alloxan diabetic rats

The glucose-lowering efficacy of a methanol extract of the stem bark of Ficus racemosa Linn. (MEBFR) (Family Moraceae) was evaluated both in normal and alloxan-induced diabetic rats. The MEBFR at the doses examined (200 and 400 mg/kg p.o.) exhibited significant hypoglycaemic activity in both experimental animal models when compared with the control group. The activity was also comparable to that of the effect produced by a standard antidiabetic agent, glibenclamide 10 mg/kg. The present investigation established pharmacological evidence to support the folklore claim that it is an antidiabetic agent.     

Anti-protozoan activities of Harungana madagascariensis stem bark extract on trichomonads and malaria

AIM OF THE STUDY: The ethanolic stem bark extract of Harungana madagascariensis (Hypericaceae), (Choisy) Poir were evaluated for their activities on Trichomonas gallinae (Rivolta) Stabler isolated from the pigeon (Columba livia). It was also tested for their anti-malarial activity on N67 Plasmodium yoelii nigeriensis (in vivo) in mice and on Plasmodium falciparum isolates in vitro. MATERIALS AND METHODS: The anti-trichomonal screening was performed in vitro using Trichomonas gallinae culture. The minimum lethal concentration (MLC) is the lowest concentration of the test extract in which no motile organisms were observed. The anti-malarial effects were determined in-vivo for suppressive, curative and prophylactic activities in mice receiving a standard inoculum size of 1 x 10(7) (0.2 ml) infected erythrocytes of Plasmodium yoelii nigeriensis intraperitoneally, and the in vitro was performed against 3 isolates of Plasmodium falciparum in a candle jar procedures. RESULTS: The IC(50) of the extract and metronidazole (MDZ) (Flagyl) on Trichomonas gallinae at 48 h are 187 and 1.56 microg/ml. The IC(50) of the extract, chloroquine (CQ) and artemether (ART) on Plasmodium falciparum are between 0.052 and 0.517 microg/ml for the extract and 0.021 and 0.0412 microg/ml for ART and CQ, respectively. The actions of the extract in in vivo study on Plasmodium yoelii nigeriensis showed that in both suppressive and prophylactic tests the percentages chemo-suppressive were between 28.6-44.8% and 30.2-78.2% respectively, while only 80 mg/kg of the extract reduced the parasitaemia level when compared to the control and the standard drugs in curative test. CONCLUSIONS: Harungana madagascariensis stem bark extract therefore exhibited significant anti-protozoan effects against Trichomonas and Plasmodium both in vivo and in vitro.     

In vitro activities of Citrus medica L. cv. Diamante (Diamante citron) relevant to treatment of diabetes and Alzheimer's disease

The present study showed for the first time the in vitro properties (antioxidant, hypoglycaemic and anticholinesterase) of Citrus medica L. cv. Diamante which belongs to the Rutaceae family. The n-hexane extract of Diamante citron peel is characterized by the presence of monoterpenes and sesquiterpenes. The most abundant constituents were two monoterpenes: limonene and gamma-terpinene. The extract showed significant antioxidant activity that was carried out using different assays (DPPH test, beta-carotene bleaching test and bovine brain peroxidation assay). Oxidative damage, caused by the action of free radicals, may initiate and promote the progression of a number of chronic diseases, including diabetes and Alzheimer's disease. Diamante citron peel extract showed hypoglycaemic activity and an anticholinesterase effect.     

飞龙掌血醇提物的抗炎镇痛作用

目的研究飞龙掌血醇提物的抗炎镇痛作用及其机制。方法大鼠用角叉菜胶致炎及福尔马林致痛,研究飞龙掌血醇提物的镇痛作用;ELISA试剂盒检测角叉菜胶实验大鼠血清中β内啡肽(β-EP)、前列腺素E2(PGE2)、5-羟色胺(5-HT)的含有量,炎症大鼠皮肤组织中肿瘤坏死因子-α(TNF-α)及白细胞介素-1β(IL-1β)的含有量,以及福尔马林实验小鼠血清中白三烯B4(LTB4)的含有量;免疫组化法观察大鼠脊髓FOS及P物质(SP)蛋白表达。结果飞龙掌血醇提物能明显降低足趾肿胀率;福尔马林实验中,飞龙掌血醇提物能明显减少舔足累积时间,降低PGE2的含有量,高剂量组尤为明显;3个剂量组均能降低血清中5-HT的含有量,高剂量和低剂量效果显著,高剂量组还能升高血清中β-EP的含有量。各剂量组均能降低皮肤组织中TNF-α和IL-1β的含有量,中、高剂量组抑制FOS蛋白表达;高剂量组明显降低血清中LTB4的含有量。结论飞龙掌血醇提物具有抗炎镇痛作用,其作用机制可能是与通过增加血清中β-EP,降低PGE2、5-HT、LTB4含有量,降低皮肤组织中TNF-α、IL-1β含有量,以及下调脊髓SP及FOS蛋白表达有关。     

A preliminary study of the biological activities of the bark extract of Piliostigma thonningii (schum) in mice

The biological activities of the stem bark of Piliostigma thonningii were studied in mice. The oral LD₅₀ of the 70% ethanol extract was 1862 mg/kg. It significantly reduced pentobarbitone-induced sleeping time after an intraperitoneal injection (p < 0.05). The extract induced persistent contractions on the guineapig ileum which were completely blocked by atropine. Mice intubated with varying doses (100,200,400 mg/kg) of the extract had diarrhoea. The extract appeared to mediate its action through a cholinergic mechanism.     

Hypoglycaemic activity of Scopariadulcis L. extract in alloxan induced hyperglycaemic rats

Scoparia dulcis L. commonly known as 'Sweet Broomweed' is widely used in Indian folk medicine for the treatment of diabetes mellitus. Oral administration of 0.15, 0.30 and 0.45 g/kg body weight of the aqueous extract of the Scoparia dulcis leaves (SLEt) for 45 days resulted in a significant reduction in blood glucose, glycosylated haemoglobin and an increase in total haemoglobin but in the case of 0.45 g/kg body weight the effect was highly significant. The aqueous extract also prevented a decrease in the body weight. An oral glucose tolerance test was also performed in experimental diabetic rats, in which there was a significant improvement in glucose tolerance in animals treated with SLEt and the effect was comparable to that of glibenclamide.     

Evaluation of the anti-inflammatory properties of Sclerocarya birrea (A. Rich.) Hochst. (family: Anacardiaceae) stem-bark extracts in rats

This study was designed to evaluate the anti-inflammatory effect of Sclerocarya birrea (family: Anacardiaceae) stem-bark aqueous and methanolic extracts in rats. Young adult, male Wistar rats (Rattus norvegicus) weighing 250-300g were used. The anti-inflammatory effects of aqueous and methanolic stem-bark extracts of the plant (SB, 500mg/kg p.o.) were examined on rat paw oedema induced by subplantar injections of fresh egg albumin (0.5ml/kg). Acetylsalicylic acid (ASA, 100mg/kg p.o.) was used as the reference anti-inflammatory agent for comparison. Both the aqueous and methanolic stem-bark extracts of S. birrea (SB, 500mg/kg p.o.) progressively and time-dependently reduced rat paw oedema induced by subplantar injections of fresh egg albumin. However, the methanolic extract of the plant produced relatively greater and more pronounced anti-inflammatory effect than its aqueous extract counterpart in the experimental animal model used. The two extracts of S. birrea stem-bark were found to be markedly less potent than ASA as anti-inflammatory agent. Although both the aqueous and methanolic extracts of S. birrea stem-bark are less potent than ASA as anti-inflammatory agent, the results of this experimental animal study indicate that the extracts possess anti-inflammatory activity, and thus lend credence to the suggested folkloric use of the plant in the management and/or control of arthritis and other inflammatory conditions in certain communities of South Africa.     

Effects of some traditional plant extracts on rat oestrous cycle compared with Clomid

It is well known that the plant kingdom contains numerous bioactive substances affecting the regulation of reproduction. The present study was undertaken to examine the putative contraceptive effects of three tradi‐ tional plant extracts from Côte d'Ivoire Pharmacopea. It concerns Afrormosia laxiflora (Papilionacea), Pterocarpus erinaceus (Papilionacea) and Cola nitida (Sterculiacea) stem bark. Data showed that treatment of rats with these plant extracts induced ovulation and oestrous cycle blockade at the dioestrous II stage. The analysis of the principal hormones involved in oestrous cycle regulation showed that the plant extracts decreased gonadotropin release (both LH and FSH). In fact, A. laxiflora, P. erinaceus and C. nitida extracts inhibited gonadotropin release as an antiestrogen‐like substance. Copyright © 2003 John Wiley & Sons, Ltd.     

Hypoglycaemic activity of Nelumbo nucifera gaertn. (Fam. Nymphaeaceae) rhizome (methanolic extract) in streptozotocin-induced diabetic rats

The hypoglycaemic effect of the rhizome extract of Nelumbo nucifera was studied in streptozotocin-induced diabetic rats. A methanol extract of the plant obtained by soxhlet extraction from finely pulverized rhizomes was used. The LD₅₀ of the extract was found to be 2 g/kg. The extract (300 mg/kg and 600 mg/kg, orally) caused a reduction of blood glucose levels in streptozotocin-induced diabetic rats by 53% (p<0.001) and 55% (p<0.001) respectively at the end of 12 h. The results of this study indicate that the methanol extract of the rhizome possesses favourable hypoglycaemic activity in hyperglycaemic animals taking chlorpropamide as a standard.     

Effects of three different doses of a fruit extract of Terminalia chebula on metabolic components of metabolic syndrome,in a rat model

There is documented evidence of the use of Terminalia chebula for various ailments in the Ayurvedic literature. The extract has been shown to possess glucose lowering activity and to improve insulin sensitivity in animal models of type 2 diabetes mellitus. The present study was carried out to study the dose response relationship of this extract in a rat model of metabolic syndrome. Six groups of rats were fed a high fructose diet (HFD) for a period of 20 days to induce metabolic syndrome. Three doses of fruit extract of T. chebula 50, 100 and 200 mg/kg were administered orally and pioglitazone 2.7 mg/kg was used as a positive control. Blood samples were collected at days 0, 20 and 40 from the tail vein. Systolic blood pressure (SBP) was measured using the tail cuff method and an oral glucose tolerance test (OGTT) was done on the day of blood collection. Administration of HFD for 20 days significantly increased fasting blood glucose (FBG), SBP and the area under the curve of OGTT. On day 40 the FBG in the 50, 100 and 200 mg/kg group was 97.33 ± 5.82 (NS), 86.83 ± 5.08 (p = 0.038) and 85.67 ± 6.74 (p = 0.15), respectively. These results show that the fruit extract of T. chebula exerts a significant and dose‐dependent glucose lowering effect in the rat model of metabolic syndrome. Copyright © 2009 John Wiley & Sons, Ltd.     

Effect of Khaya grandifoliola extract on Plasmodium berghei berghei in mice

Khaya grandifoliola stem bark extract was tested for antimalarial action against Plasmodium berghei berghei in mice. The schizontocidal activity of the extract was assessed on early and established infections using chloroquine as a standard drug. The repository activity was also investigated and pyrimethamine was used as the standard. In the early infection test (like the chloroquine group), K. grandifoliola extract was effective in suppressing the malaria infection. However, on the established infection, the extract failed to effectively suppress the infection. The extract also demonstrated residual activity.     

Anti-inflammatory, analgesic and antipyretic activities of the extract of gamboge from Garcinia hanburyi Hook f

In Thai folklore medicine, gamboge, the yellow gum-resin secreted from Garcinia hanburyi, is used for infected wound, pain and edema The ethyl acetate extract from Garcinia hanburyi (GH5763) was assessed for anti-inflammatory, analgesic and antipyretic activities using experimental animal models. It was found that GH5763 possessed inhibitory activity on acute phase of inflammation as seen in ethyl phenylpropiolate-induced ear edema and carrageenin-induced hind paw edema in rats. However, GH5763 did not elicit any inhibitory effect on arachidonic acid-induced hind paw edema. In subchronic inflammatory model, GH5763 provoked a significant reduction of both transudative and proliferative phase when tested on cotton pellet-induced granuloma model. GH5763 also reduced the alkaline phosphatase activity in serum of rats in this animal model. In the analgesic test, GH5763 elicited inhibitory activity on acetic acid-induced writhing response and on both the early and the late phase of formalin test. Moreover, GH5763 also possessed an excellent antipyretic effect when tested in yeast-induced hyperthermic rats. It is postulated that the anti-inflammatory, analgesic and antipyretic activities of GH5763 are caused by the inhibition of the prostaglandin biosynthesis.     

Effects of Sclerocarya birrea (A. rich) hochst (anacardiaceae) leaf extracts on calcium signalling in cultured rat skeletal muscle cells.

Sclerocarya birrea is a plant used widely to treat many diseases in Burkina Faso, although no scientific data has been reported about its mechanism of action. In the present study the effects of its leaf extracts were investigated on calcium signalling in rat cultured skeletal muscle cells. The results show that the different extracts (crude decoction, aqueous, ethanolic and chloroformic extracts) have significant antagonistic effect on caffeine-induced calcium release from sarcoplasmic reticulum. Crude decoction is the most active followed by ethanolic, aqueous and chloroformic extracts in dose-dependent manner and can partly justify the use of the plant in traditional medicine.     

Effects of Aloe veraingestion in the rat. II. Hormonal and metabolic characteristics

The aim of this study was to examine the effects of long-term (1.5 and 5.5 months) Aloe vera (Aloe barbadensis) ingestion on a variety of metabolic parameters of Fischer 344 male rats. Rats were fed Aloe vera powders produced by two different methods and mixed with rat chow at various concentrations. Process A Aloe was prepared from skinned Aloe filets by homogenization followed by lyophilization and included in the rat chow at the 1% level. Process B Aloe was prepared similarly except the homogenate was charcoal filtered prior to lyophilization and mixed with chow at both 1% and 10% levels. Plasma concentrations of parathyroid hormone (PTH) and calcitonin were lower in the older (7 month) Aloe fed than in the control rats of the same age. No statistically significant effects were observed at the younger age (3 month). Aloe feeding did not alter the plasma glucose and insulin levels at any age and had only minor effects on the plasma corticosterone concentrations in the older rats. Serum lipid peroxides were decreased by Aloe feeding, but the malondialdehyde production of cardiac and hepatic mitochondrial and microsomal membranes were unaffected. No alteration in protein turnover was observed in the Aloe fed rats. © 1998 John Wiley & Sons, Ltd.     

Effects of Olea europaea L. extract on the rat isolated ileum and trachea

The effects of an Olea europaea L. dried leaf extract containing 3.2% of oleuropein were investigated on the rat isolated ileum and trachea. On basal tone rat isolated ileum, Olea europaea L. extract was shown to produce a dual effect characterized by a contraction at low doses (10^?7-10^?4g/mL) and a relaxation at high doses (3.10^?4-10^?3g/mL). The extract induced contractile effect was found to involve at least histamine, 5-hydroxytryptamine and thromboxane A₂. On precontracted rat isolated ileum, the extract only induced a relaxation that was not modified by nifedipine, diltiazem, dipyridamone, verapamil or papaverine (10^?6 M). The effects of the extract were also studied on the rat isolated trachea. On basal tone organs, Olea europaea L. extract did not produce any effect, whereas, when basal tone was raised by acetylcholine (ACh 10^?3 M), the drug caused a relaxation (maximal effect 39.01% ± 5.40%) of the response to theophylline; (3.10 ± 10^?3M n = 15). It is suggested that the induced relaxation is consecutive to an increase of intracellular 3′5′ cAMP.     

Effect of Aloe vera leaves on blood glucose level in type I and type II diabetic rat models

Aloe vera (L.) Burm. fil. (= A. barbadensis Miller) (Liliaceae) is native to North Africa and also cultivated in Turkey. Aloes have long been used all over the world for their various medicinal properties. In the past 15 years, there have been controversial reports on the hypoglycaemic activity of Aloe species, probably due to differences in the parts of the plant used or to the model of diabetes chosen. In this study, separate experiments on three main groups of rats, namely, non-diabetic (ND), type I (IDDM) and type II (NIDDM) diabetic rats were carried out. A. vera leaf pulp and gel extracts were ineffective on lowering the blood sugar level of ND rats. A. vera leaf pulp extract showed hypoglycaemic activity on IDDM and NIDDM rats, the effectiveness being enhanced for type II diabetes in comparison with glibenclamide. On the contrary, A. vera leaf gel extract showed hyperglycaemic activity on NIDDM rats. It may therefore be concluded that the pulps of Aloe vera leaves devoid of the gel could be useful in the treatment of non-insulin dependent diabetes mellitus Copyright 2001 John Wiley & Sons, Ltd.     

Studies on the hypoglycaemic activity of Punica granatum seed in streptozotocin induced diabetic rats.

The hypoglycaemic activity of Punica granatum Linn. (Family Punicaceae) seed extract on rats made diabetic by streptozotocin (STZ) was investigated. The methanol extract of the seed at doses of 300 and 600 mg/kg, and chlorpropamide 200 mg/kg was administered to STZ diabetic rats. The seed extract (150, 300 and 600 mg/kg, orally) caused a significant reduction of blood glucose levels in STZ induced diabetic rats by 47% and 52%, respectively, at the end of 12 h.