Proliferation is a cellular process strongly linked to the genesis of cancer. Natural substances with antiproliferative activities are currently potential alternatives in the treatment of cancers. Dacryodes edulis, for instance, is a medicinal plant traditionally used in the treatment of cancer. Scientific studies have reported the antioxidant activity of this plant. In addition, the presence of prostate cancer chemopreventive polyphenols was reported in D. edulis extracts. Therefore, this study was aimed to evaluate the effects of the aqueous extract of D. edulis leaves on cell proliferation induced by estradiol in ovariectomized female Wistar rats. In this regard, ovariectomized (OVX) rats were cotreated with estradiol valerate (E2V) (0.75 mg/kg) and the aqueous extract of D. edulis leaves. Control groups received either the vehicle (sham-operated animals and the OVX control), E2V (0.75 mg/kg) only, or E2V (0.75 mg/kg) and tamoxifen (10 mg/kg). Treatments were administered orally for 3 consecutive days, and animals were sacrificed thereafter. Epithelial heights of the uterus and vagina were assessed. Uterine levels of total cholesterol and estradiol were determined as well. Results showed that the aqueous extract of D. edulis leaves reversed the effects of estradiol as it reduced uterine weight ( p < 0.05 ), uterine ( p < 0.05 ), and vaginal ( p < 0.001 ) epithelium heights. This antiproliferative effect of D. edulis was associated with reduced tissue (uterine) levels of estradiol ( p < 0.001 ). These results suggest that the aqueous extract of D. edulis leaves could be a potential alternative treatment for proliferation-related diseases.

The aim of this study was to evaluate the effects of the aqueous extract of Baillonella toxisperma stem bark on dexamethasone-induced insulin resistance in rats. A quantitative phytochemical study was done on the aqueous extract of Baillonella toxisperma for the total phenol, flavonoid, and flavonol determination. Insulin resistance was induced by intraperitoneal injection of dexamethasone (1 mg/kg) for 8 days, one hour before oral administration of different treatments (extract at doses of 60, 120, and 240 mg/kg and metformin at 40 mg/kg). During the test, body weight and blood glucose level were evaluated on days 1 and 8. At the last day of treatment, the glucose tolerance test was performed in rats; after that, blood samples were collected for triglycerides, total cholesterol, LDL and HDL cholesterols, transaminases (ALT and AST), and total protein level determination. Organs (heart, liver, pancreas, and kidneys) were also collected for the relative organ weight determination. The results showed that the aqueous extract of B. toxisperma is rich in total phenols, flavonoids, and flavonols. This extract significantly reversed the metabolic alterations (lipid profile, protein level, and transaminase activity) induced by dexamethasone in rats. At doses of 120 and 60 mg/kg, Baillonella toxisperma also significantly decreases (p<0.05; p<0.01) postprandial hyperglycemia in insulin resistance rats. The results suggest that Baillonella toxisperma can manage insulin resistance and may be useful for the treatment of type 2 diabetes mellitus.

Oxidation of LDL has been suggested to be an initial step in the development of atherosclerosis. This research work deals with the evaluation of antioxidant potential of Plectranthus glandulosus leaves extracts and fractions as well as its protective effects against human LDL oxidation. A preliminary quantitative phytochemical screening was carried out. Antioxidant potential was evaluated employing in vitro hydrogen peroxide, nitric oxide scavenging assays and TAOC test. The human LDL oxidation induced by CuSO4 inhibition test was also performed. Plectranthus glandulosus leaves exhibited the presence of 18.3% of saponines, 25.6% of terpenoids and 36.2% of flavonoids. EAF exhibited highest hydrogen peroxide and nitric oxide scavenger activity (IC50 13.63µg/ml and 24.59 µg/ml respectively). Ascorbic acid exhibited an IC50 value of 15.39µg/ml in hydrogen peroxide assay and 22.96 µg/ml in nitric oxide scavenging activity. EAF exhibited a higher TAOC (optical density 0.186±0.00) than that of ascorbic acid (0.162±0.001) at the concentration of 25µg/ml while at 200µg/ml N-BUTF exhibited a higher optical density (1.261±0.001) than that of ascorbic acid (1.065±0.001). EAF lengthened the lag time of the CD formation up to 150mins at the concentration 1mg/ml. TBARS formation inhibition at the concentration 0.5mg/ml, were no significant different between n-butanol (68.55%) ethyl acetate fraction (68.21%) and quercetin 67.69%). Plectranthus glandulosus is a promising prospect as an anti-atherosclerotic agent and needs a detailed study to establish the same. Key words: Plecthrantus glandulosus; oxidation; LDL; atherosclerosis, antioxidant.

Background Diabetes mellitus is a metabolic disorder characterised by chronic hyperglycemia. The present research work aimed to evaluate the hypoglycaemic, hypolipidemic and antioxidant effects of leafy stems of Cissus polyantha Gilg & Brandt in insulin resistant rats. Methods The oral glucose tolerance test (OGTT) was performed in normal rats. Hyperglycemia was induced for 8 days by a daily subcutaneous injection of dexamethasone (1 mg/kg) one hour after pretreatment of animals with metformin (40 mg/kg) and C. polyantha extract (111, 222 and 444 mg/kg). Body weight, blood glucose, insulin level, lipid profile, insulin biomarkers, cardiovascular indices and oxidative stress biomarkers were evaluated. Results For OGTT, the extract (444 mg/kg) produced a significant drop in blood sugar at the 60th (p < 0.01), 90th (p < 0.01) and 120th min (p < 0.05). Morever, the extract at doses of 222 and 111 mg/kg significantly reduced blood sugar at the 60th (p < 0.01) and 90th min (p < 0.05) respectively. Otherwise, C. polyantha (444 and 222 mg/kg) significantly (p < 0.001) increased body weight and decreased blood sugar on the 4th and 8th days of treatment in insulin resistant rats. The extract also significantly decreased (p < 0.001) serum insulin level, hyperlipidemia, insulin resistance index and cardiovascular indices, and increased gluthathione level, and superoxide dismutase and catalase activity. Conclusion The aqueous extract of Cissus polyantha leafy stems (AECPLS) possess hypoglycemic, hypolipidemic and antioxidant activities that could justify its use in traditional medicine for the prevention and treatment of diabetes mellitus and its complications.

Background. Diarrheal diseases are a major cause of morbidity and mortality throughout the world and particularly in developing countries. Nauclea diderrichii is a plant used in traditional medicine in the treatment of anemia, fever, gastric ulcer, malaria, abdominal pain, skin infections, and diarrhea. The present work is aimed at evaluating the antisecretory and spasmolytic activities of aqueous and ethanolic stem bark extracts of Nauclea diderrichii in Wistar rats. Methods. The effect of aqueous and ethanolic extracts of Nauclea diderrichii was tested at doses of 100, 200, and 300 mg/kg on castor oil-induced secretory diarrhea, misoprostol-induced fluid accumulation, and the effect of pretreatment with yohimbine and glibenclamide. They were also tested on normal motility and castor oil- and carbachol-induced hypermotility. Results. The results showed that the aqueous and ethanolic extracts of Nauclea diderrichii significantly ( p < 0.001 ) inhibited castor oil-induced secretory diarrhea at all the doses. Both extracts significantly ( p < 0.001 ) inhibit fluid accumulation induced by misoprostol. The pretreatment with glibenclamide reduced the antidiarrheal activity of aqueous extract of Nauclea diderrichii. The pretreatment with yohimbine did not alter the effect of the aqueous extract of Nauclea diderrichii. On intestine transit as on castor oil- and carbachol-induced motility, the aqueous and ethanolic extracts at doses of 100 and 200 mg/kg reduced significantly ( p < 0.05 , p < 0.01 , and   p < 0.001 ) the travelled distance by charcoal and peristaltic index. Conclusions. The study demonstrated that the aqueous and ethanolic extracts of Nauclea diderrichii possess antisecretory and antispasmolytic properties hence its use in traditional medicine against diarrhea.

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Cissus polyantha (Vitaceae) is a plant used in Cameroonian traditional medicine for the treatment of diabetes. The aims of this study were to evaluate the in vitro antioxidant and antidiabetic activities of the aqueous extract of Cissus polyantha leafy stems. The enzyme inhibitory activity was determined in vitro on α-amylase and α-glucosidase enzymes, followed by confirmative study in vivo on normal rats (oral starch and sucrose tolerance tests at doses of 111, 222, and 444 mg/kg). The ferric reducing antioxidant power and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) antiradical activity of the extract were examined to evaluate the antioxidant potential of the extract. The total content of phenols, flavonoids, and tannins of the extract were also determined. The results showed an inhibitory effect of the extract on the α-amylase and α-glucosidase activities with IC50 values of 216.14 and 182.40 μg/mL, respectively. The extract at doses of 222 and 444 mg/kg induced a significant decrease in postprandial glycaemia during the starch and sucrose tolerance tests. A remarkable antiradical activity of the extract was obtained although lower than that of the standard product. The aqueous extract of leafy stems of Cissus polyantha has an interesting inhibitory activity on the α-amylase and α-glucosidase enzymes, as well as an antioxidant potential, thus validating its use in traditional medicine for the treatment of diabetes mellitus and its complications.

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