Antioxidative burst and hepatoprotective effects of ethanol root extract of Hippocratea africana against paracetamol-induced liver injury.

CONTEXT: Hippocratea africana (Willd.) Loes. ex Engl. (Celastraceae) root is used traditionally as an antipoison or antidote to treat liver diseases. OBJECTIVE: To evaluate antioxidative burst and hepatoprotective potentials of H. africana against paracetamol-induced liver injury in rats. MATERIALS AND METHOD: Antioxidative burst activity of the extract (1-100 µg/ml) in whole blood, neutrophils and macrophages was investigated using a luminol/lucigenin-based chemiluminescence assay. The hepatoprotective effect of the extract (200-600 mg/kg) was evaluated by the assay of liver function parameters, antioxidant enzymes and histopathological studies of the liver. GC-MS analyses of hexane and dichloromethane fractions were also carried out. RESULTS AND DISCUSSION: The root extract/fractions exerted pronounced inhibition of oxidative burst activity in whole blood, neutrophils (intracellular and extracellular) and macrophages (3.04-99.70%). The administration of the root extract caused significant (p < 0.05-0.001) reduction of high levels of liver enzymes (AST, ALT and ALP), total cholesterol, direct and total bilirubin as well as elevation of serum levels of total protein, albumin and antioxidant enzymes (SOD, CAT, GPx and GSH). Histology of the liver sections of extract and silymarin-treated animals showed reductions in the pathological features compared to the paracetamol-treated animals. The chemical pathological changes were consistent with histopathological observations suggesting a marked hepatoprotective effect of the root extract of H. africana. The GC-MS analysis revealed some pharmacologically active compounds. CONCLUSION: The results show that the root extract of H. africana has hepatoprotective potential probably due to its antioxidative burst activity.

Antimicrobial activity of Carpolobia lutea extracts and fractions.

Carpolobia lutea (G. Don) (Polygalaceae) is a tropical medicinal plant putative in traditional medicines against gonorrhea, gingivitis, infertility, antiulcer and malaria. The present study evaluated the antimicrobial, antifungal and antihelicobacter effects of extracts C. lutea leaf, stem and root. The extracts were examined using the disc-diffusion and Microplates of 96 wells containing Muller-Hinton methods against some bacterial strains: Eschericia coli (ATCC 25922), E. coli (ATCC10418), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), Staphyllococus aureus (ATCC 6571), Enterococcus faecalis (ATCC 29212) and Bacillus subtilis (NCTC 8853) and four clinical isolates: one fungi (Candida albican) and three bacteria (Salmonella, Sheigella and staphylococcus aureus). The Gram-positive bacteria: Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Bacillus subtilis (ATCC 19659) and the Gram-negative bacteria: Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Cândida albicans (ATCC 18804) and Helicobacter pylori (ATCC 43504). Some of these extracts were found to be active against some tested strains but activity against H. pylori was >1000mg/ml and good fungistatic activity against C. albican. The MIC against C. albican is in the order n-HF > CHF > ETF= EAF.The order of potency of fraction was the ethanol root > n-HF leaf > ethanol fraction stem > chloroform fraction leaf = ethyl acetate fraction leaf. Polyphenols were demonstrated in ethanol fraction, ethyl acetate fraction, crude ethyl acetate extract and ethanol extract, respectively. These polyphenols isolated may partly explain and support the use of C. lutea for the treatment of infectious diseases in traditional Ibibio medicine of Nigeria.

Nephroprotective effect of Croton zambesicus root extract against gentimicin-induced kidney injury.

OBJECTIVE: To evaluate the kidney protective effect of ethanolic root extract of Croton zambesicus (C. zambesicus) against gentimicin-induced kidney injury in rats. METHODS: The root extract (27-81 mg/kg) was administered to rats for eight days with concurrent administration of gentimicin (100 mg/kg) daily for the same period of time. Protective effect of the extract was evaluated in serum levels of creatinine, urea, and uric acid as well as some ions like sodium, potassium and chloride. Histological examination of the kidneys from different treatment groups were also carried out. RESULTS: Administration of the root extract significantly reduced histopathological changes in the kidneys of the extract-treated rats especially in the rats treated with lower doses of the extract (27 and 54 mg/kg). The levels of serum urea and creatinine were also reduced significantly (P<0.01) at these doses with no observable effect on the levels of uric acid and ions. CONCLUSIONS: The kidney - protective activity of this extract could be due to its antioxidant and free radical scavenging activities.

Antimalarial and analgesic activities of ethanolic leaf extract of Panicum maximum.

OBJECTIVE: To evaluate antiplasmodial and analgesic activities of ethanolic leaf extract/fractions of Panicum maximum. METHODS: The crude leaf extract (47-190 mg/kg) and fractions (chloroform, ethyl acqeous and methanol; 96 mg/kg) of Panicum maximum were investigated for antiplasmodial activity against chloroquine sensitive Plasmodium berghei infections in mice and for analgesic activity against chemical and heat-induced pains. The antiplasmodial activity during early and established infections as well as prophylactic were investigated. Artesunate at 5 mg/kg and pyrimethamine at 1.2 mg/kg were used as positive controls. Analgesic activity of the crude extract/fractions was also evaluated against acetic acid, formalin and heat-induced pains. RESULTS: The extract and its fractions dose-dependently reduced parasitaemia induced by chloroquine sensitive Plasmodium berghei infection in prophylactic, suppressive and curative models in mice. These reductions were statistically significant (P<0.001). They also improved the mean survival time from 13 to 28 days compared with control (P<0.001). The activities of extract/fractions were incomparable to that of the standard drugs (Artesunate and pyrimethamine). On chemically and thermally-induced pains, the extract inhibited acetic acid and formalin-induced inflammation as well as hot plate-induced pain in mice. These inhibitions were statistically significant (P<0.001) and in a dose-dependent fashion. CONCLUSIONS: Panicum maximum leaf extract has antiplasmodial and analgesic activities which may in part be mediated through the chemical constituents of the plant.

Antiinflammatory, analgesic and antipyretic activities of ethanolic root extract of Croton zambesicus.

The ethanolic root extract of C. zambesicus (27-81mg/kg) was evaluated for antiiflammatory, analgesic and antipyretic properties in mice. The extract (27-81mg/kg) demonstrated a weak antiinflammatory activity. However, a significant (P<0.01-0.001) analgesic and antipyretic activities were observed in all the experimental models tested. The extract may be exerting its effects through central mechanisms. These findings confirms its ethnomedical use in the treatment of malarial-associated symptoms.

Subchronic toxicity studies of the ethanolic root extract of Croton zambesicus.

Subchronic toxicity study of the crude root extract of Croton zambesicus (27-81 mg/kg), which is used traditionally as malarial remedy, was carried out in rodents to evaluate the safety profile. Effect of the extract on body weights, haematological indices as well as liver and kidney functions and histology of various organs were investigated. Subchronic treatment of rats for 21 days caused comparable increase in body weights of rats in extract treated and control groups. The extract caused a dose-dependent increases in RBC, PCV, Hb, WBC, bleeding time and clotting time. The increases were only significant (P<0.05) at the highest dose of the extract (81 mg/kg) for RBC and WBC when compared to control. There was no significant (P>0.05) differences in the means of other haematological parameters in the extract treated groups compared to control. The extract caused significant (P<0.05-0.01) increases in the level of serum total protein, ALT, ALP, total bilirubin and total cholesterol. The was no significant (P>0.05) changes in the levels of albumin and AST. The extract did not produce any significant (P>0.05) changes in the mean concentrations of urea, creatinine, Na+, K+, and Cl- ions of rats in the extract treated groups compared to that of control. Histopathologic analysis of the vital organs revealed no significant lesions in the brain, liver, kidney, heart, spleen, ovary, and testis. The results suggest the extract to be safe when taken orally though with an insignificant effect on the liver.

Antimicrobial activity of root extract and crude fractions of Croton zambesicus.

The root extract and fractions of Croton zambesicus were screened for antimicrobial activity against some typed and pure cultures of bacterial and fungal species. These were carried out by the Plate-hole diffusion method on Mueller-Hinton agar (MHA) for bacteria and Sabouraud Dextrose Agar (SDA) for the fungi. The Minimum Inhibitory Concentrations (MICs) of test samples found to be active by the diffusion test were determined based on the macrodilution method. The crude extract as well as chloroform and n-hexane fractions had activity against B. subtilis only. While ethyl acetate fraction had a wide spectrum of activity against all the bacteria organisms tested with a promising minimum inhibitory concentrations. However, the crude extract and the fractions were inactive against all the fungal species tested. This result confirms its ethnomedicinal use in the treatment of microbial infections.

Analgesic and antimalarial activities of crude leaf extract and fractions of Acalypha wilkensiana.

AIM OF THE STUDY: Antiplasmodial and analgesic activities of leaf extract and fractions of Acalypha wilkensiana were evaluated to ascertain the folkloric claim of its antimalarial and analgesic activities. MATERIALS AND METHODS: The crude leaf extract (220-659 mg/kg) and fractions (chloroform and aqueous; 440 mg/kg) of Acalypha wilkensiana were investigated for antiplasmodial activity against chloroquine sensitive Plasmodium berghei infections in mice and for analgesic activity against chemical and heat-induced pains. The antiplasmodial activity during early and established infections as well as prophylactic activity were investigated. Chloroquine (5mg/kg) and pyrimethamine (1.2mg/kg) were used as positive controls. Thin films made from tail blood of each mouse were used to assess the level of parasitaemia of the mice. Analgesic activity of the crude extract was also evaluated against acetic acid, formalin and heat-induced pains. RESULTS: The extract and its fractions dose-dependently reduced parasitaemia induced by chloroquine sensitive Plasmodium berghei infection in prophylactic, suppressive and curative models in mice. These reductions were statistically significant (p<0.001). They also improved the mean survival time (MST) from 16 to 22 days relative to control (p<0.01-0.001). The activities of extract/fractions were incomparable to that of the standard drugs used (chloroquine and pyrimethamine). On chemically and thermally induced pains, the extract inhibited acetic acid and formalin-induced inflammation as well as hot plate-induced pain in mice. These inhibitions were statistically significant (p<0.001) and in a dose-dependent fashion. CONCLUSION: The antiparasitaemic and analgesic effects may in part be mediated through the chemical constituents of the plant.

Antiulcer and anticonvulsant activity of Croton zambesicus.

The ethanolic root extract of Croton zambesicus was investigated for its potential to protect gastric mucosa against ulcers induced by indomethacin, ethanol and reserpine. The anticonvulsant activity of the root extract against pentylene tetrazol (PTZ)- and picrotoxin-induced convulsion in mice was also studied. The extract (27-81 mg/kg) produced a significant (P<0.005-0.001) dose-dependent effects against the ulcerogenic effect of different agents used; indomethacin, ethanol and reserpine. The effect of the extract was lower than that of the standard drug, cimetidine (100 mg/kg) in the indomethacin and reserpine-induced ulcer models and higher than that of propranolol (40 mg/kg) in ethanol-induced ulcer model. The extract (27-81 mg/kg) could not protect mice from convulsion in both PTZ--and picrotoxin-induced convulsion. The root extract significantly (P<0.01-0.001) delayed the onset and latency of convulsion caused by PTZ and picrotoxin. The root extract possesses antiulcer and anticonvulsant properties.

Antiplasmodial activity of root extract and fractions of Croton zambesicus.

AIM OF THE STUDY: Antiplasmodial activity of root extract and fractions of Croton zambesicus were evaluated to ascertain the folkloric claim of its antimalarial activity and elucidate its antiplasmodial mechanism of action. MATERIAL AND METHOD: The crude ethanolic root extract (27-81 mg/kg) and gradient fractions (n- hexane, chloroform, ethyl acetate and methanol; 54 mg/kg) of Croton zambesicus were investigated for antiplasmodial activity against chloroquine--sensitive Plasmodium berghei infections in mice. The antiplasmodial activity during early and established infections as well as the prophylactic activity were investigated. Chloroquine (5 mg/kg) and pyrimethamine (1.2 mg/kg) were used as positive controls. Thin films made from tail blood of each mouse were used to assess the level of parasitaemia of the mice. Oxidant generation potentials of the crude extract and fractions was also evaluated to elucidate their mechanism of action. RESULTS: The crude root extract (27-81 mg/kg) demonstrated significant (P<0.01-0.001) schizonticidal activity during early and established infections and also had prophylactic activity. The activity was comparable to that of the standard drug used (chloroquine 5 mg/kg, pyrimethamine 1.2 mg/kg). Methanol, ethyl acetate and chloroform fractions had comparative in vivo antiplasmodial activity and oxidant generation potentials. CONCLUSION: The antiplasmodial activity of this root extract and fractions which is likely to be through peroxidation confirms the folkloric use of this plant.

Effects of methanolic extract of Asparagus pubescens root on sexual behavior and pituitary hormone secretion on Wistar rats during pregnancy and lactation.

We investigated the effect of methanolic extract of Asparagus pubescens root on sexual behavior and on pituitary hormone secretion during pregnancy and lactation on Wistar rats. Different doses (0.25, 0.5, 1.0 and 1.5g/kg) of the extract, given in a single bolus dose or in four (divided) daily injections (0.0625, 0.125, 0.25 and 0.375 mg/(kg day)), inhibited sexual behavior when given to proestrous females in a dose-dependent manner, with the high doses (1.0-1.5g/kg) inhibiting significantly the lordosis quotient. All treated females showed aggressive behavior towards the males to a similar extent irrespective of dose. Fertilization rate, pregnancy, delivery and litter size were normal. Birth weight and growth rates of the pups were also unaffected indicating no deleterious effects of extract on offspring development. The extract had significant effects on preovulatory luteinizing hormone (LH), prolactin (PRL) and progesterone (P4) release. Divided doses of 1.0 and 1.5g/kg significantly decreased preovulatory LH, PRL and P4 release. Administration of 0.5 or 1.5g/kg in bolus dose, produced significant inhibition of preovulatory LH and PRL while 1.5g/kg had no effect. Progesterone was not modified while 1.0g/kg dose caused a decrease in GH. 0.25g/kg produced a paradoxical increase in preovulatory PRL secretion, also seen on day 4 of pregnancy. During pregnancy, both dose regimens were effective in inhibiting the afternoon peaks in prolactin secretion at all dose levels with the exception of 0.25g/kg. There were no effects on the second half of pregnancy or on the suckling-induced PRL release on day 3 postpartum. Circulating GH was scarcely affected on day 3 postpartum. All the results taken together, indicate that the contraceptive effects of the extract may be exerted through interference with neural mechanisms that control preovulatory hormone release and sexual behavior.

Evaluation of anti-diarrhoeal and anti-ulcerogenic potential of ethanol extract of Carpolobia lutea leaves in rodents.

The effect of ethanol extract of Carpolobia lutea leaves on experimentally induced diarrhoea and ulcers was studied in rodents. The extract (245-735 mg/kg) inhibited small intestinal transit time (15.10-45.03%), castor oil-induced diarrhoea (25.69-43.54%) and fluid accumulation (7.53-34.15%), respectively, as well as indomethancin (47.64-79.79%) and ethanol-induced (65.63-89.65%) ulcer models. The various degrees of inhibitions were statistically significant (p < 0.001). The phytochemical screening confirmed the presence of tannins, saponins and flavonoids. Others include cardiac glycosides, anthraquinones and terpenes. The median lethal dose (LD50) was determined to be 2449.49 mg/kg body weight. Though the mechanism of action of the extract may not be fully understood, the extract may in part be mediating its actions through its inhibitory effects on alpha2-adrenoceptor and cholinergic (anti-muscarinic receptor) systems or through the actions of its active metabolites.

Anti-nociceptive and anti-inflammatory effects of methanolic extract of Asparagus pubescens root in rodents.

The effect of methanolic extract of Asparagus pubescens was investigated on chemical, thermal-induced pain as well as fresh egg albumin-induced inflammation and pentylenetetrazol (PTZ)-induced convulsion in rodents. The extract dose-dependently (0.25-1.5 g/kg) inhibited acetic acid-induced writhing, formalin-induced pain licking and hot plate-induced pain in mice. The extract significantly inhibited both the fresh egg albumin-induced inflammation in rats as well as PTZ-induced convulsion in mice. These inhibitions were statistically significant (P < 0.02-0.001). It increased the latencies of both clonic and tonic convulsions and delayed their mortalities. Its ability to reduce both neurogenic and non-neurogenic pains may be related to its active constituents such as tannins, saponins, steroid and flavonoids.