Résumé
Objective: To evaluate the anti-arthritic effect of aqueous and methanolic extracts of Distemonanthus benthamianus. Methods: Monoarthritis was induced by an injection of 0.3 mL zymosan A (0.9% NaCl, v/v) in the right posterior knee joints of rats. Then, joint diameter and pain threshold were determined. Polyarthritis was induced by an intracaudal injection of complete Freund’s adjuvant and rats were treated from day 14 post 1st complete Freund’s adjuvant injection until 28 day. The clinical, hematological, biochemical and oxidative stress parameters were evaluated. In addition, histological analysis of the knee joint was perfomed in both tests. Results: The aqueous and methanolic extracts of Distemonanthus benthamianus at a dose of 500 mg/kg ameliorated zymosan A-induced monoarthritis, as evidenced by reduced joint diameter, increased pain threshold, as well as improved joint architecture. In addition, both extracts of Distemonanthus benthamianus markedly increased body weight and pain threshold, while reducing paw edema in polyarthritic rats. They also led to a marked decrease in platelets and white blood cells (P<0.05), as well as a significant increase in red blood cells, hemoglobin and hematocrit (P<0.05). The aqueous and methanolic extracts of Distemonanthus benthamianus significantly reduced alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase activities, while increasing serum protein levels (P<0.05) with no significant variation in creatinine level. Moreover, both extracts increased catalase and glutathione activities (P<0.05), and inhibited malondialdehyde and nitric oxide production (P<0.01 and P<0.001) in the liver and kidneys. Histological analysis of the joints showed that both extracts triggered tissue reparation. Conclusions: Distemonanthus benthamianus could be used as a potential candidate in the treatment of rheumatoid arthritis.
Résumé
Objective: To explore the immunomodulatory, anti-inflammatory, anti-oxidant and anti-arthritic activity of aqueous and methanolic extracts of Nauclea pobeguinii stem bark.Methods: For in vitro assays, the production of reactive oxygen species (chemiluminescence technique), the proliferation of T cells (liquid scintillation counter method), as well as the inhibition of cyclooxygenase, lipoxygenase, protein denaturation, and free radicals [DPPH, ABTS and nitric oxide (NO) inhibition methods] were evaluated. For in vivo assays, a polyarthritis model was induced by complete Freund's adjuvant in rats. The aqueous and methanolic extracts of Nauclea pobeguinii stem bark were administered orally at 150 and 300 mg/kg. After 28 days of treatment, the total blood was taken to quantify the hematological parameters and the serum was used to evaluate the biochemical parameters (alanine aminotransferase, aspartate transaminase, phenylalnine ammonialyase, and proteins) and oxidative stress parameters (malondialdehyde, catalase, superoxide dismutase, glutathione and NO), and then the knee joint was removed for histological analysis. Results: The extracts of Nauclea pobeguinii significantly reduced the production of intra- and extracellular reactive oxygen species and decreased T cell proliferation. They had an inhibitory effect on cyclooxygenase, lipoxygenase, and protein denaturation, and both extracts had antioxidant capacity on DPPH, ABTS and NO. Both extracts alleviated joint inflammation and pain sensitivity after complete Freund's adjuvant injection, reduced alanine aminotransferase, aspartate transaminase, alkaline phosphatase, NO and malondialdehyde levels, increased protein concentration, superoxide dismutase, catalase and glutathione activity, and restored the cytoarchitecture of the joint after complete Freund's adjuvant injection. Conclusions: The aqueous and methanolic extracts of Nauclea pobeguinii have immunomodulatory, anti-inflammatory, anti-oxidant and anti-arthritic properties.
Résumé
Objective:To explore anti-hyperalgesic properties of methanol extract of Piptadeniastrum africanum stem bark (PAME) and it possible action mechanism.Methods:PAME was tested on carrageenan induced hyperalgesia using plantar test (thermal) and analgesymeter (mechanical) in rats,on prostaglandin E2 (PGE2) induced mechanical hyperalgesia and vincristine induced neuropathic pain in rat,both with analgesymeter.Modulators of NO/cGMP/K+ channel pathway and endogenous opioids receptor antagonists and/or agonists were used to determine the possible action mechanism of PAME.Results:PAME significantly decreased carrageenan induced thermal and mechanical hyperalgesia,as well as PGE2 induced mechanical hyperalgesia.PAME significantly protected the animals against the installation of neuropathic pain.Anti-nociception activity produced by PAME was significantly blocked in animals pre treated with all the antagonists (naloxone,NW-nitro-L-arginine methyl ester (L-NAME),methylene blue and glibenclamide).Conclusions:Results of this study reveal that,PAME administrate orally,can induce anti-hyperalgesic action against installation of inflammatory pain as well as neuropathic pain.The mechanism underlying PAME antihyperalgesic effect could probably be associated with an activation of opioid receptors and NO/cGMP/K+ channel pathway.
Résumé
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.