Curative effects of Distemonanthus benthamianus Baillon. Trunk-bark extracts on enteropathogenic Escherichia coli 31-induced diarrhea in rats.

Background Distemonanthus benthamianus is used in the Western part of Cameroon to treat diarrheal episodes and infections. This study assessed its trunk-bark extracts activity against enteropathogenic Escherichia coli 31 (EPEC 31)-induced diarrhea in rats. Methods Aqueous and methanolic extracts were analyzed through high-performance liquid chromatography (HPLC). In vitro minimum inhibitory and bactericidal concentrations (MICs/MBCs) were evaluated on Enterococcus faecalis (ATCC 10,541), E. coli (ATCC 6539), Klebsiella pneumoniae (ATCC 13,883), Salmonella typhi (ATCC 6539) strains and on Proteus mirabilis, Pseudomonas aeruginosa (PA 01) and Shigella flexneri isolates using the microdilution method. Diarrhea was induced by inoculating rats with EPEC 31 (1.5 × 108 CFU/mL; p.o). Serum transaminases level assay and enzyme-linked immunosorbent assay (ELISA) for cytokines determination were performed. Hematoxylin-eosin (H-E) staining was used for intestinal tissue analysis. Results HPLC fingerprints of extracts showed presence of gallic acid and other unidentified compounds. The lowest MIC of 256 µg/mL was obtained with methanolic extract. At 100 mg/kg, both extracts significantly (p<0.001) inhibited diarrhea, with the methanolic extract being the most active. In addition, the methanolic extract significantly (p<0.001) increased the relative mass of the liver compared to negative control (Tween-DMSO 8%). The aqueous extract (100 mg/kg) significantly (p<0.01) increased alanine aminotransferase (ALT) serum concentration; while the methanolic extract (100 mg/kg) exhibited similar effect over aspartate aminotransferase (AST). At 50 and 100 mg/kg, the methanolic extract significantly (p<0.05 and p<0.01) decreased the Interleukin-1ß (IL-1ß) serum level, compared to negative control (Tween-DMSO 8%). Serum level of tumor necrosis factor alpha (TNF-α) significantly (p<0.001) decreased with 100 mg/kg of aqueous extract and all doses of methanolic extract. Inhibition of inflammatory cells tissue infiltration and epithelial regeneration was highly noticed in the ileum and colon of extracts-treated rats than in ciprofloxacin-treated animals. Conclusion These findings suggest that D. benthamianus trunk-bark extracts displayed therapeutic effects against infectious diarrhea in rats.

Preventive effects of Aframomum melegueta extracts on the reproductive complications of propylthiouracil-induced hypothyroidism in male rat.

Recent studies have demonstrated that hypothyroidism is associated with infertility. This work was undertaken to evaluate the protective effects of Aframomum melegueta on testicular functions and fertility of hypothyroid male rats. Male rats were orally treated with propylthiouracil (PTU: 10 mg/kg) in combination with plant aqueous or methanol seed extract (20 and 100 mg/kg) for 56 days. Vitamin E and clomiphene citrate served as positive controls. On day 47 of treatment, each male was mated with two adult females for fertilization potential evaluation. At the end of the treatment, genital sex organ weights, sperm characteristics, testicular histology, oxidative status, plasmatic hormones and fertility potential were evaluated. Results indicated that PTU created hypothyroidism characterised by a significant increase in TSH with reduction of T3 and T4. PTU also lowered genital sex organ weights, sperm count, viability and motility, plasmatic levels of luteinising hormone, follicle-stimulating hormone and testosterone, and increased prolactin, cholesterol and testicular oxidative stress. Alteration in sperm morphology, testis and epididymis histology, and fertilization potential was also noticed. Co-administration with A. melegueta extracts successfully reversed PTU-induced infertility without any effect on thyroid hormones. These results provide evidence that A. melegueta has a protective effect on fertility in hypothyroid condition.

Immunological In Vivo and In Vitro Investigations of Aqueous Extract of Stem Bark of Pterocarpus erinaceus Poir (Fabaceae).

BACKGROUND: Macrophages are the first cells to recognize invading foreign bodies and are central to cell mediated and humoral immunity. Therefore, the activation of macrophages is a key event for effective innate and adaptive immunity. Pterocarpus erinaceus has been reported to control infectious diseases, but the mechanism remains to be elucidated. In this study, we demonstrated the immune-modulatory effect of aqueous extract of P. erinaceus using human macrophages and lymphocytes, as well as mice. METHODS: Hot water was used to extract P. erinaceus from the stem bark. Its effect on lymphocytes was measured by evaluating proliferative response and delayed hypersensitivity. Phagocytic activity of macrophages were measured based on neutral red uptake assay, nitric oxide production and myeloperoxidase and phosphatase acid activity. Hematopoietic and infectious activities were analyzed using the effect on infectious stress and chloramphenicol-induced leucopenic mice model. RESULTS: Aqueous extract showed stronger stimulatory effects on the neutral red uptake, production of nitric oxide and phosphatase acid activity in lipopolysaccharide-activated macrophages. In addition, aqueous extract significantly stimulated the proliferation of phytohemagglutinin-activated lymphocytes, enhanced delayed hypersensitivity response to erythrocytes and attenuated infection-induced fever. Furthermore, aqueous extract also significantly increased the rate of recovery of white blood cell levels in chloramphenicol-induced leucopenia mice. CONCLUSIONS: The results suggest that aqueous extract of P. erinaceus stem bark is able to modulate the immune system and has potential effects in clinical conditions when an immune-enhancing and anti-infectious effect is desired.

Antidiarrhoeal and antibacterial activity of aqueous and methanolic leaves extracts of Dissotis thollonii Cogn. (Melastomataceae)

Objective: To investigate the phytochemical test and selected pharmacological activities (antidiarrhoeal and antibacterial activity) of the aqueous and methanolic leaves extracts of Dissotis thollonii Cogn. (Melastomataceae) (D. thollonii). Methods:The aqueous and methanolic extracts were evaluated for their antibacterial activities on the in vitro growth of 2 clinical isolates (Staphylococcus aureus and Shigella flexneri), and 5 reference bacteria strains [Escherichia coli ATCC 8739 (E. coli), E. coli ATCC 10536, Salmonella typhi ATCC 6539, Enterobacter aerogenes ATCC 13048 and E. coli ATCC 11775] by determining the minimum inhibitory concentrations (MICs) and bactericidal concentrations using broth microdilution method as well as on the infectious, secretory and osmotic induced diarrhoea models in rats. Results:The aqueous extract inhibited the in vitro growth of all bacteria tested (the 05 reference bacteria strains and the 02 clinical isolates), with MICs values comprised between 32 and 512 μg/mL, whereas the methanolic extract has done the same with the MICs values located between 128 and 512 μg/mL. In vivo, the methanolic and aqueous extracts provoqued at all doses, a significant decrease (P Conclusions:The leaves of D. thollonii thus have antibacterial and antidiarrhoeal effects, which could result from their activities on blocking the inhibiting effects of the bacterial enzymes, inhibiting the bacterial protein synthesis, allowing the rupture of the lipopolysaccharidic membrane, as well as on inhibiting prostaglandins-E2 synthesis or increasing the hydroelectrolytic reabsorption. These results attestted the ethnopharmacological use of D. thollonii leaves in the treatment of diarrhoea and gastro-intestinal infections.

Effects of Ficus asperifolia on normal rat estrus cyclicity

<p><b>OBJECTIVE</b>To evaluate Ficus asperifolia (Moraceae) (F. asperifolia) effecting on regular estrus cycle of Wistar rats.</p><p><b>METHODS</b>Air-dried fruits of F. asperifolia were extracted using water. Prior to the test, vaginal smear was monitored daily for a 3-week period to select females with normal (regular) estrous cycle. Those with regular estrus cycle weighing between 150-170 g were randomized into three sets of 15 animals each. Each set was then divided into three groups: Group 1 (control) was orally administered with distilled water (10 mL/kg body weight) once a day for 1 week starting from the proestrus stage. Groups 2 and 3 were respectively treated with 100 and 500 mg/kg body weight of the plant aqueous extract. The two other sets of 15 animals each were similarly treated as the first set for 3 weeks and 6 weeks respectively. Estrus cycle pattern was monitored before and during plant extract application whereas lipid profile, ovary, uterus and liver growth indices were determined at the end of each treatment.</p><p><b>RESULTS</b>F. asperifolia did not disrupt (0%) the order of appearance of normal estrus cycle stages, namely, proestrus, estrus, metestrus and diestrus. Short-term treatment (1 week duration) exhibited high frequency of appearance of proestrus and estrus stages while mid- (3 weeks) and long-term (6 weeks) treatments revealed constancy in the frequency of all stages irrespective to animal groups. The plasma and organ lipid profile, as well as ovary, uterus and liver growth remained unchanged when compared to distilled water-treated animals. Following long-term administration of plant extract (6 weeks), no adverse effect was noticed.</p><p><b>CONCLUSIONS</b>Our data partially support the use of F. asperifolia in common medicine.</p>

Hypoglycemic and hypolipidemic effects of Bersama engleriana leaves in nicotinamide/streptozotocin-induced type 2 diabetic rats.

BACKGROUND: The present investigation was aimed at evaluating the hypoglycemic and hypolipidemic properties of the aqueous and methanolic extracts from Bersama engleriana leaves in streptozotocin/nicotinamide (STZ-NA)-induced type 2 diabetic rats. METHODS: Animals were orally treated for 4 consecutive weeks with Bersama engleriana extracts at doses of 300 or 600 mg/kg. The anti-diabetic effect was examined by measuring blood glucose (BG) at 0, 1, 14 and 28 days after STZ-NA treatment and, total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and triglycerides (TG) levels at sacrifice (day 29). Glibenclamide (0.25 mg/kg) was used for comparison. RESULTS: STZ-NA-induced diabetic rats showed moderate to significant increases in the levels of BG, TG, TC, LDL-C while body weight, HDL-C levels and relative weights of liver and pancreas were decreased compared to controls (non diabetic rats). Administration of the plant extracts to STZ-NA diabetic rats resulted in a significant decrease in BG, TG, TC and LDL-C and the dose 600 mg/kg of the methanolic extract was the most effective; HDL-C level was markedly increased after four weeks compared to untreated diabetic rats. A dose-dependent increase in the relative weights of the diabetogenic organs was observed in the Bersama engleriana groups. It can be also noticed that the methanolic extract, especially the dose 600 mg/kg (p<0.001), produced more effects than glibenclamide and aqueous extract. Rats treated with glibenclamide (0.25 mg/kg) generally gave lower results compared to groups treated with plant extracts. CONCLUSION: Results of the present study showed that Bersama engleriana extracts and especially its methanolic extract possess antidiabetogenic properties and beneficial effects on diabetic hyperlipidemia. All these effects could be due to the bioactive components revealed in the Bersama engleriana extracts such as triterpenes and phenols and which could justify its ethnomedical use.