Design, formulation and evaluation of Chasmanthera dependens Hochst and Chenopodium ambrosioides Linn based gel for its analgesic and anti-inflammatory activities

BACKGROUND: The incidence of pain and inflammation in West Africa and in fact globally, continues to increase at an alarming rate. This research was conducted to investigate the analgesic and anti-inflammatory activities of leaf extracts of Chasmanthera dependens and Chenopodium ambrosioides; formulate and evaluate polyherbal gels from their combination in a bid to providing topical therapeutic solutions to pain and inflammation. METHODS: Pre-formulation studies (phytochemical analysis, in vitro analgesic and anti-inflammatory activities) were conducted on the methanol leaf extracts of Chasmanthera dependens and Chenopodium ambrosioides. Individual and polyherbal gels were prepared using polymer carbopol 940 (1%) at combination ratios of 0:100, 25:75, 50:50, 75:25 and 100:0 Chasmanthera:Chenopodium. These herbal gels were evaluated for physical parameters, pH, viscosity, extrudability and spreadability. Analgesic and anti-inflammatory activities of herbal gels were evaluated by their inhibitory activities (percentage inhibition) against COX-2, TNF-α, IL-10, PGE-2 and compared with commercial diclofenac gel. RESULTS: The phytochemicals of the two extracts detected gave varied contents of major classes of secondary metabolites. The pre formulation inhibitory studies of the two extracts exhibited dose dependent inhibitory activities against COX-2, TNF-α, IL-10, PGE-2. The physical appearance, homogeneity, and consistency of the herbal formulations were good. The herbal gels were spreadable with good extrudability. The pH of the herbal gels ranged from 4.5 ± 0.4 to 5.2 ± 0.4. The viscosity of the herbal gels ranged between 4.3 ± 0.2 and 4.7 ± 0.4 Pas. The herbal gels exhibited significant differences in inhibitory activities against COX-2, TNF-α, IL-10, PGE-2 when compared with control commercial diclofenac gel. CONCLUSION: The outcomes, including the inhibition of mediators COX-2, TNF-α, IL-10, PGE-2, confirm the use of the plant extracts under study, the individual and polyherbal gels formulated for the potential topical therapeutic treatment of pain and inflammation.