In vivo and In vitro Anti-inflammatory and Free Radical Scavenging Activities of Methonolic Extract of Different Parts from Nauclea vanderguchtii De Wild (Rubiaceae)

Abstract

Aims: Nauclea vanderguchtii (N. vanderguchtii) species belongs to the family Rubiaceae and it is widely used in traditional Cameroonian medicine against inflammatory diseases such as arthritis, rheumatism and gastric disorders. The present study was aimed to evaluate anti-inflammatory effect of a methanol extracts of leaves, stems, roots and barks with multiparametric analyses through in vitro assays and an in vivo model. Methodology: Leaves, stems, barks and roots of N. vanderguchtii were air-dried and a methanolic extract was further obtained. Red blood cell membrane stabilization and protein denaturation were carried out as screening assays for anti-inflammatory activity in vitro, following by Diphenyl picryl-hydrazyl (DPPH), 2,2’- azino-bis – (3 - ethylbenzothiazoline -6- sulfonique (ABTS) and Ferric Reducing Antioxidant Power ( FRAP) antioxidant activity. Furthermore, the anti-inflammatory capacity of leaves and stems methanolic extract was evaluated in vivo by carrageenan-induced oedema. Results: Each part of Nauclea vanderguchtii, effectively and significantly stabilized red blood cell membrane. The methanol leaves extract exhibited better effect (53.12%), followed by stems (50.55%), barks (50.98%) and roots (49.6%) compare to an ibuprofen (51.16%), a standard reference drug. Those extracts also inhibited the denaturation of the egg albumin (P ˂ .05; P ˂ .01). Methanol stem and leaves extracts from plant were the effective scavengers of ABTS - radical (95.92 ± 0.37%), DPPH - radical (91.12 ± 0.13%). FRAP of methanolic extract was concentration-dependent. Moreover, methanol leaves extract of Nauclea vanderguchtii, significantly (P<.01) prevented paw edema with the maxima 58.97% (200 mg / kg). Conclusion: This study shows that N. vanderguchtii extracts possess significant anti-inflammatory and antiradical activities. These activities are more pronounced in leaves than other parts of plant and justify the traditional use.