Betulinic and ursolic acids from Nauclea latifolia roots mediate their antimalarial activities through docking with PfEMP-1 and PfPKG proteins.

BACKGROUND: Chemotherapies target the PfEMP-1 and PfPKG proteins in Plasmodium falciparum, the parasite that causes malaria, in an effort to prevent the disease's high fatality rate. This work identified the phytochemical components of Nauclea latifolia roots and docked the chemical compounds against target proteins, and examined the in vivo antiplasmodial effect of the roots on Plasmodium berghei-infected mice. METHODS: Standard protocols were followed for the collection of the plant's roots, cleaning, and drying of the roots, extraction and fraction preparation, assessment of the in vivo antiplasmodial activity, retrieval of the PfEMP-1 and PfPKG proteins, GCMS, ADME, and docking studies, chromatographic techniques were employed to separate the residual fraction's components, and the Swis-ADME program made it possible to estimate the drug's likeness and pharmacokinetic properties. The Auto Dock Vina 4.2 tool was utilized for molecular docking analysis. RESULTS: The residual fraction showed the best therapeutic response when compared favorably to amodiaquine (80.5%) and artesunate (85.1%). It also considerably reduced the number of parasites, with the % growth inhibition of the parasite at 42.8% (D2) and 83.4% (D5). Following purification, 25 compounds were isolated and characterized with GCMS. Based on their low molecular weights, non-permeation of the blood-brain barrier, non-inhibition of metabolizing enzymes, and non-violation of Lipinski's criteria, betulinic and ursolic acids were superior to chloroquine as the best phytochemicals. Hence, they are lead compounds. CONCLUSION: In addition to identifying the bioactive compounds, ADME, and docking data of the lead compounds as candidates for rational drug design processes as observed against Plasmodium falciparum target proteins (PfEMP-1 and PfPKG), which are implicated in the pathogenesis of malaria, the study has validated that the residual fraction of N. latifolia roots has the best antiplasmodial therapeutic index.

Toxicological evaluation of a polyherbal formulation on testicular function and gonadal histomorphology in exposed Wistar rats.

Introduction: Dr Iguedo Goko Cleanser® is a herbal formulation (HF) widely marketed in southern Nigeria and purported to be very efficacious for the management of various diseases including giardiasis, toilet infections, hypertension, diabetes, ulcer, impotence, low libido, low sperm count amongst others. Medicinal plants reportedly produce an array of adverse reactions capable of inducing harmful conditions, including death. Aim: This study evaluated the subchronic toxicity concern of HF on testicular function and gonadal histoarchitecture in Wistar rats. Methods: Thirty Wistar rats of both sexes were randomly divided into six groups (5/group) and were orally administered HF for 60 days. The control groups received 5 mL/kg of distilled water; the treatment groups were administered 476.24 and 158.75 mg/kg body weight of HF each for both male and female rats. Using standard procedures, semen analysis was done for all male rats. Animals were anaesthetised and sacrificed on the 62nd day; the gonads were eviscerated, weighed and fixed in 10% buffered formalin for histopathological examinations. Results: Significant (p < 0.05) increase in sperm count relative to control as well as spermatotoxic effects were observed in male rats. Histologically, the ovary presented some degrees of pathologies: cloggy appearing ovarian cortex with a display of a tumour-like cortical area, scantily displayed primordial follicles, haemorrhagic blood vessels, atretic secondary follicle, and eroding granulosa cells amongst others. Testicular histopathology showed abnormal seminiferous tubules' histoarchitecture, degenerated spermatids, distorted spermatogenic cells' orientation, and displaced spermatids into the luminal space. Conclusion: Herbal drugs are usually regarded to be completely safe due to their natural sources, however, this study discovered exposure-related toxic effects of Dr Iguedo Goko Cleanser® on testicular function and gonadal histomorphology. The findings recommend extreme caution with chronic use and avoidance whenever possible.

In vitro and in vivo antimalarial activity and chemical profiling of sugarcane leaves.

Saccharum officinarum Linn. (sugarcane, Family-Poaceae) is employed in Ibibio traditional medicine for the treatment of various infections and diseases such as malaria. We This study aims to assess the antiplasmodial effect of the leaf extract and fractions on human malaria parasite (Plasmodium falciparum) in vitro, and rodent malaria parasite (P. berghei) in vivo, and analyse the bioactive components of the active fraction(s). The leaf extract and fractions of S. officinarum were prepared and their growth inhibitory effects tested against the chloroquine resistant P. falciparum strain (Dd2) and P. berghei infection in mice. An acute toxicity of the extract was determined. A combination of gas chromatography and liquid chromatography-mass spectrometry, and nuclear magnetic resonance spectroscopy was applied for metabolites profiling of crude extract and active fractions. The leaf extract and fractions demonstrated moderate activity against P. falciparum with the dichloromethane fraction producing the most potent activity (EC50 = 15.4 µg/mL). The leaf extract (170-510 mg/kg, p.o., LD50 = 1732 mg/kg) and fractions demonstrated significant (p < 0.05-0.001) effect on P. berghei infection in prophylactic  tests as well as in established infection with n-butanol fractions producing the highest effect. An unusual sulphur-containing compound, dilaurylthiodipropionate, fatty acids, phenolic acids, flavonoid and flavonoid glycoside were identified in the active fractions. These results give credence to the use of sugarcane leaves as malarial remedy locally by confirming the in vitro and in vivo antiplasmodial potential of leaf extract/fractions of S. officinarum.

In vivo antihyperglycaemic and antihyperlipidemic activities and chemical constituents of Solanum anomalum.

Solanum anomalum is a plant used ethnomedically for the treatment of diabetes. The study was aimed to validate ethnomedical claims in rat model and identify the likely antidiabetic compounds. Leaf extract (70-210 mg/kg/day) and fractions (140 mg/kg/day) of S. anomalum were evaluated in hyperglycaemic rats induced using alloxan for effects on blood glucose, lipids and pancreas histology. Phytochemical characterisation of isolated compounds and their identification were performed using mass spectrometry and NMR spectroscopy. Bioinformatics tool was used to predict the possible protein targets of the identified bioactive compounds. The leaf extract/fractions on administration to diabetic rats caused significant lowering of fasting blood glucose of the diabetic rats during single dose study and on repeated administration of the extract. The hydroethanolic leaf extracts also enhanced glucose utilization capacity of the diabetic rats and caused significant lowering of glycosylated hemoglobin levels and elevation of insulin levels in the serum. Furthermore, triglycerides, LDL-cholesterol, and VLDL-cholesterol levels were lowered significantly, while HDL-cholesterol levels were also elevated in the treated diabetic rats. There was absence or few pathological signs in the treated hyperglycaemic rat pancreas compared to that present in the pancreas of control group. Diosgenin, 25(R)-diosgenin-3-O-α-L-rhamnopyranosyl-(1→4)-ß-D-glucopyranoside, uracil, thymine, 1-octacosanol, and octacosane were isolated and identified. Protein phosphatases along with secreted proteins are predicted to be the major targets of diosgenin and the diosgenin glycoside. These results suggest that the leaf extract/fractions of S. anomalum possess antidiabetic and antihyperlipidemic properties, offer protection to the pancreas and stimulate insulin secretion, which can be attributable to the activities of its phytochemical constituents.

Isolation and characterization of bioactive xanthones from Hippocratea africana (Willd.)Loes.ex Engl. (Celastraceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Hippocratea africana root is used in African folk medicine for the treatment of several ailments, including pain and inflammation. AIM OF THE STUDY: To isolate anti-inflammatory and analgesic compounds from the roots of H. africana, with accompanying antioxidant potentials. MATERIALS AND METHODS: Dichloromethane, ethyl acetate, and aqueous fractions of H. africana roots, and isolated compounds from the bioactive ethyl acetate fraction were evaluated for anti-inflammatory and analgesic activities using the xylene induced oedema in mice and thermal induced pain models, respectively. The antioxidant potentials of isolated compounds were tested in 2,2-diphenyl-1-picryhydrazyl radical and ferric reducing antioxidant power assays. Structures were elucidated on the basis of spectroscopic analyses, including 1D and 2D NMR experiments, ionization mass spectrometry, and comparison with literature data. RESULTS: Isoathyriol (1,3,7-trihydroxy-6-methoxyxanthone) and norathyriol (1,3,6,7-tetrahydroxyxanthone) were isolated from the potent anti-inflammatory and analgesic ethyl acetate fraction of H. africana roots. Isoathyriol and norathyriol demonstrated good anti-inflammatory, analgesic, and antioxidant properties compared with the standards used in each assay. CONCLUSIONS: This study substantiates the use of H. africana root extract in the alleviation of inflammation and pain, and reports the characterization of secondary metabolites in H. africana and for the first time the presence of xanthones in Hippocratea genus.

In Vivo Efficacy and Metabolism of the Antimalarial Cycleanine and Improved In Vitro Antiplasmodial Activity of Semisynthetic Analogues.

Bisbenzylisoquinoline (BBIQ) alkaloids are a diverse group of natural products that demonstrate a range of biological activities. In this study, the in vitro antiplasmodial activity of three BBIQ alkaloids (cycleanine [compound 1], isochondodendrine [compound 2], and 2'-norcocsuline [compound 3]) isolated from the Triclisia subcordata Oliv. medicinal plant traditionally used for the treatment of malaria in Nigeria are studied alongside two semisynthetic analogues (compounds 4 and 5) of cycleanine. The antiproliferative effects against a chloroquine-resistant Plasmodium falciparum strain were determined using a SYBR green 1 fluorescence assay. The in vivo antimalarial activity of cycleanine is then investigated in suppressive, prophylactic, and curative murine malaria models after infection with a chloroquine-sensitive Plasmodium berghei strain. BBIQ alkaloids (compounds 1 to 5) exerted in vitro antiplasmodial activities with 50% inhibitory concentration (IC50) at low micromolar concentrations and the two semisynthetic cycleanine analogues showed an improved potency and selectivity compared to those of cycleanine. At oral doses of 25 and 50 mg/kg body weight of infected mice, cycleanine suppressed the levels of parasitemia and increased mean survival times significantly compared to those of the control groups. The metabolites and metabolic pathways of cycleanine were also studied using high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry. Twelve novel metabolites were detected in rats after intragastric administration of cycleanine. The metabolic pathways of cycleanine were demonstrated to involve hydroxylation, dehydrogenation, and demethylation. Overall, these in vitro and in vivo results provide a basis for the future evaluation of cycleanine and its analogues as leads for further development.

Antiplasmodial activity and cytotoxicity of ethanol extract of Zea mays root.

OBJECTIVE: Zea mays root decoction that has been traditionally used for the treatment of malaria by various tribes in Nigeria, was evaluated for antimalarial potential against malaria parasites using in vivo and in vitro models. MATERIALS AND METHODS: The root extract of Zea mays was investigated for antimalarial activity against Plasmodium berghei in mice using rodent malaria models; suppressive, prophylactic and curative tests and in vitro antiplasmodial activity against chloroquine-sensitive (Pf 3D7) and resistant (Pf INDO) strains of Plasmodium falciparum using SYBR green assay method. Median lethal dose and cytotoxic activity against HeLa and HEKS cells were assessed and phytochemical screening was also carried out using standard procedures. RESULTS: The LD50 value of root extract was found to be 474.34 mg/kg. The crude extract (45-135 mg/kg, p.o) showed significant (p<0.05-0.001) antimalarial activity against P. berghei infection in suppressive, prophylactic and curative tests with a prolonged survival time. The crude extract also showed moderate activity against both chloroquine-sensitive (Pf 3D7) and resistant (Pf INDO) strains of P. falciparum with an IC50 value of 71.62±3.38 µg/ml (for Pf 3D7) and 63.76±4.12 µg/ml (for Pf INDO). The crude extract was not cytotoxic to the two cell lines tested with TC50 of >100 µg/ml against both HeLa and HEKS cell lines. CONCLUSION: These results suggest that the root extract of Zea mays possesses antimalarial activity against both chloroquine-sensitive and resistant malaria and these data justify its use in ethnomedicine to treat malaria infections.

Hepatoprotective activity of the extract of Homalium letestui stem against paracetamol-induced liver injury.

OBJECTIVE: Homalium letestui Pellegr (Flacourtiaceae) has been traditionally used by the Ibibios of Southern Nigeria to treat stomach ulcer, malaria and other inflammatory diseases and Yorubas of western Nigeria as an antidote. This study evaluates the hepatoprotective properties of the ethanol extract of the plant stem. MATERIALS AND METHODS: The hepatoprotective effect of the extract of the stem of the plant (200-600 mg/kg) was evaluated by the assay of liver function parameters, namely total and direct bilirubin, serum protein and albumin, total cholesterol, alanine aminotransaminase (ALT), aspartate aminotransaminase (AST), and alkaline phosphatase activities (ALP), antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), reduced glutathione (GSH) and histopathological study of the liver. Also, GCMS analysis of n-butanol fraction of the extract was carried out. RESULTS: Administration of the extract of the stem of the plant caused a significant (p<0.05 - 0.001) dose-dependent reduction of high levels of liver enzymes (ALT, AST 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 from 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 marked hepatoprotective effect of the extract of H. letestui stem. GCMS analysis of n-butanol fraction revealed the presence of 16 bioactive compounds. CONCLUSION: The results show that the extract of H. letestui has hepatoprotective potential which may be due to the antioxidant activity of its phytoconstituents.

Antimalarial and antiplasmodial activity of husk extract and fractions of Zea mays.

CONTEXT: Zea mays L. (Poacae) husk decoctions are traditionally used in the treatment of malaria by various tribes in Nigeria. OBJECTIVE: To assess the antimalarial and antiplasmodial potentials of the husk extract and fractions on malaria parasites using in vivo and in vitro models. MATERIALS AND METHODS: The ethanol husk extract and fractions (187-748 mg/kg, p.o.) of Zea mays were investigated for antimalarial activity against Plasmodium berghei using rodent (mice) malaria models and in vitro activity against chloroquine sensitive (Pf 3D7) and resistant (Pf INDO) strains of Plasmodium falciparum using the SRBR green assay method. Median lethal dose and cytotoxic activities against HeLa and HEKS cells were also carried out. The GCMS analysis of the most active fraction was carried out. RESULTS: The husk extract (187-748 mg/kg, p.o.) with LD50 of 1874.83 mg/kg was found to exert significant (p < 0.05-0.001) antimalarial activity against P. berghei infection in suppressive, prophylactive and curative tests. The crude extract and fractions also exerted prominent activity against both chloroquine sensitive (Pf 3D7) and resistant (Pf INDO) strains of P. falciparum with the ethyl acetate fraction exerting the highest activity with IC50 values of 9.31 ± 0.46 µg/mL (Pf 3D7) and 3.69 ± 0.66 µg/mL (Pf INDO). The crude extract and fractions were not cytotoxic to the two cell lines tested with IC50 values of >100 µg/mL against both HeLa and HEKS cell lines. DISCUSSION AND CONCLUSION: These results suggest that the husk extract/fractions of Zea mays possesses antimalarial and antiplasmodial activities and these justify its use in ethnomedicine to treat malaria infections.

Antimalarial, antiplasmodial and analgesic activities of root extract of Alchornea laxiflora.

CONTEXT: Alchornea laxiflora (Benth.) Pax. & Hoffman (Euphorbiaceae) root decoctions are traditionally used in the treatment of malaria and pain in Nigeria. OBJECTIVE: To assess the antimalarial, antiplasmodial and analgesic potentials of root extract and fractions against malarial infections and chemically-induced pains. MATERIAL AND METHODS: The root extract and fractions of Alchornea laxiflora were investigated for antimalarial activity against Plasmodium berghei infection in mice, antiplasmodial activity against chloroquine sensitive (Pf 3D7) and resistant (Pf INDO) strains of Plasmodium falciparum using SYBR green assay method and analgesic activity against experimentally-induced pain models. Acute toxicity study of the extract, cytotoxic activity against HeLa cells and GCMS analysis of the active fraction were carried out. RESULTS: The root extract (75-225 mg/kg, p.o.) with LD50 of 748.33 mg/kg exerted significant (p < 0.05-0.001) antimalarial activity against P. berghei infection in suppressive, prophylactive and curative tests. The root extract and fractions also exerted moderate activity against chloroquine sensitive (Pf 3D7) and resistant (Pf INDO) strains of P. falciparum with the ethyl acetate fraction exerting the highest activity with IC50 value of 38.44 ± 0.89 µg/mL (Pf 3D7) and 40.17 ± 0.78 µg/mL (Pf INDO). The crude extract was not cytotoxic to HeLa cells with LC50 value >100 µg/mL. The crude extract and ethyl acetate fraction exerted significant (p < 0.05-0.001) analgesic activity in all pain models used. DISCUSSION AND CONCLUSIONS: These results suggest that the root extract/fractions of A. laxiflora possess antimalarial, antiplasmodial and analgesic potentials and these justify its use in ethnomedicine to treat malaria and pain.

Anti-inflammatory and antinociceptive activities of Solenostemon monostachyus aerial part extract in mice.

OBJECTIVE: Solenostemon monostachyus is used in traditional medicine for the treatment of various ailments such as ulcer, hypertension, pains and inflammatory diseases. Evaluation of anti-inflammatory and analgesic activities of S. monostachyus aerial parts was carried out to ascertain its uses in traditional medicine. MATERIALS AND METHODS: The aerial parts of S. monostachyus was cold extracted by soaking the dried powdered material in ethanol. The aerial parts crude extract (75 -225 mg/kg) of S. monostachyus was investigated for analgesic and anti-inflammatory activities using various experimental models; acetic acid, formalin and thermal- induced pains models for analgesic study and carrageenin, egg albumin and xylene - induced edema models for anti-inflammatory investigation. RESULTS: The extract caused a significant (p<0.05 - 0.001) dose-dependent reduction of inflammation and pains induced by different phlogistic agents used. These effects were comparable to those of the standard drug, (ASA, 100 mg/kg) used in some models. CONCLUSION: The anti-inflammatory and analgesic effects of this plant may in part be mediated through the chemical constituents of the plant and the results of the analgesic action suggest central and peripheral mechanisms. The findings of this work confirm the ethno medical use of this plant to treat inflammatory conditions.

Hepatoprotective activity of Mammea africana ethanol stem bark extract.

OBJECTIVE: The stem bark of Mammea africana Sabine (Guttiferae), (M. africana) a common plant that has been traditionally used to treat various diseases and ailments was evaluated for hepatoprotective potentials against paracetamol-induced liver injury in rats. MATERIALS AND METHODS: The hepatoprotective effect of the stem bark extract (30-90 mg/kg) was evaluated by the assay of liver function parameters, namely total and direct bilirubin, serum protein and albumin, total cholesterol, alanine aminotransaminase (ALT), aspartate aminotransaminase (AST), and alkaline phosphatase activities (ALP), antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH) and histopathological study of the liver. RESULTS: Administration of the stem bark extract caused a significant (p<0.05 - 0.001) dose-dependent reduction of high levels of liver enzymes (ALT, AST 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 marked hepatoprotective effect of the stem bark extract of M. africana. CONCLUSION: The results show that the stem bark extract of M. africana has hepatoprotective potential which may be due to its antioxidant activity.

Antipyretic and antimalarial activities of Solenostemon monostachyus.

CONTEXT: Solenostemon monostachyus P. Beauv (Lamiaceae) is an important herb used traditionally in the treatment of malaria, fever, and other diseases. OBJECTIVES: Antiplasmodial and antipyretic activities of S. monostachyus aerial extract were evaluated to ascertain the folkloric claim of its antimalarial and antipyretic activities. MATERIALS AND METHODS: The extract (75-225 mg/kg) and fractions (chloroform and aqueous; 150 mg/kg) of S. monostachyus were investigated for suppressive, prophylactic, and curative antiplasmodial activities against chloroquine-sensitive Plasmodium berghei infections in Swiss albino mice and for antipyretic activity against 2,4-dinitrophenol and yeast-induced pyrexia. Artesunate (5 mg/kg) and pyrimethamine (1.2 mg/kg) were used as positive controls for antiplasmodial models. Thin films made from tail blood of each mouse were used to assess the level of parasitaemia of the mice. RESULTS: The extract/fractions progressively reduced parasitaemia induced by chloroquine sensitive P. berghei infection in prophylactic (28.48-71.72%), suppressive (12.52-72.47%), and curative (22.4-82.34%) models in mice. These reductions were statistically significant (p < 0.01-0.001). They also improved significantly (p < 0.01-0.001) the mean survival time (MST) from 12.26 to 25.63 d relative to control (11.36 d). The activities of extract/fractions were incomparable with that of the standard drugs used (artesunate and pyrimethamine). The extract exerted prominent inhibition of pyrexia on dinitrophenol (87.33-90.11%, 5 h) and yeast (56.22-65.33, 5 h) induced pyrexia. Inhibition was significant (p < 0.05-0.001) from 3 to 5 h post-administration of extract and in a dose-dependent fashion. CONCLUSION: The plant may possess antiplasmodial and antipyretic effects which may in part be mediated through the chemical constituents of the plant.

Anti-inflammatory and antinociceptive activities of Homalium letestui.

CONTEXT: Homalium letestui Pellegr (Flacourtiaceae) is used in various decoctions traditionally by the Ibibios of the Niger Delta of Nigeria to treat stomach ulcer, malaria and other inflammatory diseases, as well as an aphrodisiac. OBJECTIVE: To investigate the anti-inflammatory and antinociceptive activities of the stem extract of the plant. MATERIALS AND METHODS: The ethanol stem extract (500, 750, 1000 mg/kg, i.p.) of H. letestui was investigated for anti-inflammatory activity using carrageenan, egg albumin-induced and xylene-induced ear edema models and analgesic activity using acetic acid-induced writhing, formalin-induced paw licking and thermal-induced pain models. The ethanol extract was administered to the animals orally, 30 min to 1 h depending on the model, before induction of inflammation/pain. The LD50 was also determined. GC-MS analysis of dichloromethane fraction was carried out. RESULTS: The extract caused a significant (p < 0.05-0.001) reduction of inflammation induced by carrageenan (8.3-70.0%), egg albumin (10.0-71.42%) and xylene (39.39-84.84%). The extract also reduced significantly (p < 0.05-0.001) pain induced by acetic acid (44.22-73.65%), formalin (55.89-79.21%) and hot plate (93.0-214.5%). The LD50 was determined to be 4.38 ± 35.72 g/kg. DISCUSSION AND CONCLUSION: The results of this study suggest that the ethanol stem extract of H. letestui possesses anti-inflammatory and analgesic properties which may in part be mediated through the chemical constituents of the plant as revealed by the GC-MS.

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.

Cellular antioxidative, cytotoxic, and antileishmanial activities of Homalium letestui.

OBJECTIVE: Homalium letestui Pellegr (Flacourtiaceae) is used in traditional medicine in parts of Nigeria for the treatment of malaria, ulcer, and inflammatory diseases and as an aphrodisiac. This investigation was aimed to evaluate the cytotoxic, immunomodulatory, and antileishmanial properties of stem extract and fractions of Homalium letestui (H. letestui). MATERIALS AND METHODS: Cytotoxic activity against HeLa cells was done using sulphorhodamine (SRB) method and DNA interaction activity using gel electrophoresis. Immunomodulatory activity of the extract in whole blood, neutrophils, and macrophages was also investigated using luminol/lucigenin-based chemiluminescence assay. The extract and fractions were similarly screened for antileishmanial activity against promastigotes of Leishmania major in vitro. The GCMS analysis of the most active fraction against HeLa cells was carried out. RESULTS: The stem extract exerted prominent cytotoxic activity with the dichloromethane fraction exhibiting the most pronounced effect (GI50 -5.12±1.45 µg/ml, LC50- 57.3±2.33 µg/ml, TGI -12.6±0.87 µg/ml). The crude extract and the fractions did not interact with DNA when investigated using electrophoresis. The extract significantly ((p<0.05 - 0.001) inhibited oxidative burst activity in whole blood (-27.90-66.90%), isolated polymorphonuclear cells (PMNs) (16.50-67.0%), and mononuclear cells (MNCs) (4.31-98.50%) when two different phagocytosis activators (serum opsonizing zymosan-A and PMA) were used. The extract also exhibited moderate antileishmanial activity against promastigotes of Leishmania major in vitro. GCMS analysis of active fraction revealed pharmacologically active compounds. CONCLUSION: These results suggest that the stem extract/fractions of H. letestui possess cytotoxic, immunomodulatory, and antileishmanial activities.

Antiplasmodial and analgesic activities of Clausena anisata.

OBJECTIVE: Antiplasmodial and analgesic activities of the leaf extract and fractions of Clausena anisata (C. anisata) were evaluated for antimalarial and analgesic activities. METHODS: The crude leaf extract (39-117 mg/kg) and fractions (chloroform and acqeous; 78 mg/kg) of C. anisata were investigated for antiplasmodial activity against chloroquine-sensitive Plasmodium berghei (P. berghei) infections in mice using suppressive, prophylactic and curative models and analgesic activity against acetic acid, formalin and heat-induced pains. Artesunate, 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. RESULTS: The extract and its fractions dose-dependently reduced parasitaemia induced by chloroquine-sensitive P. berghei 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 17 to 21 days relative to control (P<0.01 - 0.001). 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: The antiplasmodial and analgesic effects of this plant may in part be mediated through its chemical constituents and it can be concluded that the C. anisata possess significant antimalarial and analgesic properties.

Antiplasmodial and antiulcer activities of Melanthera scadens.

OBJECTIVE: To evaluate the antimalarial and antiulcerogenic activities of leaf extract and fractions of Melanthera scandens (M. scandens). METHODS: The crude leaf extract (37-111 mg/kg) and fractions (chloroform, ethylacetate and methanol; 78 mg/kg) of M. scadens were investigated for antiplasmodial activity against chloroquine-sensitive Plasmodium berghei infections in mice and for antiulcer activity against experimentally-induced ulcers. The antimalarial activity during early and established infections as well as prophylactic was investigated. Artesunate (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. Antiulcer activity of the crude extract was also evaluated against indomethacin, ethanol and histamine induced ulcers. 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 9.28 to 17.73 days as compared with the control (P<0.01-0.001). The activities of extract/fractions were incomparable to that of the standard drugs i.e. artesunate and pyrimethamine. On experimentally-induced ulcers, the extract inhibited indomethacin, ethanol and histamine induced ulcers. These inhibitions were statistically significant (P<0.001) and in a dose-dependent fashion. CONCLUSIONS: The antiplasmodial and antiulcerogenic effects of this plant may in part be mediated through the chemical constituents of the plant.

Anti-inflammatory and analgesic activities of Melanthera scandens.

OBJECTIVE: To evaluate the anti-inflammatory and analgesic activities of leaf extract of Melanthera scandens (M. scandens). METHODS: The crude leaf extract (39-111 mg/kg) of M. scandens was investigated for anti-inflammatory and analgesic activities using various experimental models. The anti-inflammatory activity was investigated using carragenin, egg-albumin induced oedema models, while acetic acid, formalin-induced paw licking and thermal-induced pain models were used to evaluate the antinociceptive property. RESULTS: The extract caused a significant (P<0.05 - 0.001) dose-dependent reduction of inflammation and pains induced by different agents used. CONCLUSIONS: The leaf extract possesses anti-inflammatory and analgesic effects which may be mediated through the phytochemical constituents of the plant.