Pain and inflammation are the commonest manifestations of various pathologies, and are associated with high morbidities, debility, and economic strife globally, especially in underdeveloped regions of sub-Saharan Africa. The currently available conventional analgesic and anti-inflammatory drugs cause serious side effects, some of which are life threatening, are unaffordable, and unavailable to all patients, especially in low-income countries, hence the need for better alternatives. In the current study, the in vivo anti-inflammatory, analgesic, and in vitro cytotoxic activities of the Phytexponent preparation comprising the ethanolic extracts of Viola tricolor, Echinacea purpurea, Allium sativum, Matricaria chamomilla, and Triticum repens were investigated. The carrageenaninduced paw oedema technique was adopted to investigate the anti-inflammatory activity of the Phytexponent in experimental mice, at doses of 15.625 mg/Kg BW, 31.25 mg/Kg BW, 62.5 mg/Kg BW, 125 mg/Kg BW, 250 mg/Kg BW and 500 mg/Kg BW, with Indomethacin (10 mg/Kg BW) as positive control drug. The paw sizes of respective animals were measured using a plethysmographic technique, and the values used to calculate the percentage reduction in oedematous paw size, as an indicator of anti-inflammatory activity of the Phytexponent. The acetic acid-induced writhing technique was used to determine the analgesic activity of the Phytexponent in experimental Swiss albino mice at similar doses as those used for anti-inflammatory assay and indomethacin (4 mg/Kg BW) as the reference drug. Then, the number of wriths were recorded and expressed as the percentage inhibition of writhing. The standard 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay technique was used to investigate the in vitro cytotoxic effects of the Phytexponent in Vero E6 cell line with cyclophosphamide as a positive cytotoxic agent. The percentage inhibitions of cell proliferation (percentage cytotoxicity) were determined according to a standard procedure. The study findings revealed that the Phytexponent preparation exerted significant anti-inflammatory effects in carrageenan-induced paw oedema mouse model, which ranged from 1.117±0.193% at the first hour to 11.162±0.091% at the fourth hour, at a dose of 31.25 mg/Kg BW, 6.240±0.242 % at the first hour to 17.407±0.186% at the fourth hour at a dose of 62.60 mg/Kg BW, 9.645±0.020% at the first hour to 31.795±0.090% at the fourth hourat a dose of 125 ,g/Kg BW, and 14.000±0.102% at the first hour to 37.931±0.133% in the fourth hour, at a dose of 250 mg/Kg BW (p<0.05). Notably, the Phytexponent significantly inhibited inflammation in a doseand time-dependent manner (p<0.05). The Phytexponent preparation exhibited significant analgesic activity (p<0.05) in experimental mice as depicted by reduced writhing frequencies (high percentage inhibitions of acetic acid-induced writhing), which increased from 55.054±0.174% at a dose of 31.25 mg/Kg BW to 94.982±0.098% at a dose of 250 mg/Kg BW, in a dose-dependent manner (p<0.05). The Phytexponent exhibited significantly higher analgesic activity at doses of 125 mg/Kg BW (75.924±0.253%) and 250 mg/Kg BW (94.982±0.098%) than indomethacin (64.786±0.098%), indicating higher analgesic efficacy. The Phytexponent preparation was not cytotoxic to Vero E6 cells as indicated by high CC50 value (>1000 µg/ml) compared to cyclophosphamide (CC50= 2.48µg/ml). The present study indicated that the Phytexponent formulation has significant in vivo anti-inflammatory and analgesic activities in mice models and is not cytotoxic to Vero E6 cell line. Therefore, based on the study findings, the Phytexponent formulation is a potential source of safe analgesic and anti-inflammatory associated phytocompounds. Further empirical studies, determination of mode(s) of anti-inflammatory and analgesic efficacy, and safety of the Phytexponent and its bioactive phytochemicals should be undertaken.

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