IN VITRO ASSESSMENT OF ARGINASE INHIBITORY ACTIVITY OF SCELETIUM TORTUOSUM IN RAW 264.7 MACROPHAGE CELLS WITH RELEVANCE TO VARICOSE VEIN PATHOLOGY

AbstractSceletiumtortuosum is a medicinal plant traditionally recognized for its diversepharmacological properties. The present study evaluated the arginase inhibitory and antiinflammatory activities of its hydroalcoholic root extract in LPS-stimulated RAW 264.7murine macrophages. Authenticated roots were shade-dried, powdered, and extracted using70% hydroalcoholic solvent by maceration, yielding 21.6% of a dark brown semisolidextract. Preliminary phytochemical evaluation indicated the presence of alkaloids, flavonoids,phenolics, and other secondary metabolites. Cytotoxicity was assessed using the MTT assay,and the extract showed high cellular compatibility, with cell viabilities of 96.34 ± 0.64%,90.54 ± 0.35%, and 88.36 ± 0.84% at 250, 500, and 1000 µg/mL, respectively. Arginaseactivity was successfully induced by LPS and 8-bromo-cAMP, increasing from 18.78 ± 0.37to 87.45 ± 1.22 urea units. Treatment with the extract significantly reduced arginase activityto 30.76 ± 0.54 urea units, corresponding to 64.83% inhibition, compared with 72.76% for LNorvaline. The extract also reduced nitrite production from 21.480 ± 0.341 to 16.397 ± 0.190µM/mL, representing a 23.67% reduction. Restoration of total protein content furthersuggested improved cellular integrity. These findings demonstrate that S. tortuosumpossesses significant arginase inhibitory and anti-inflammatory activity with low cytotoxicity.Its phytoconstituents, particularly mesembrine alkaloids, flavonoids, and phenoliccompounds, may contribute to these effects. The extract therefore shows potential as a naturaltherapeutic candidate for inflammation-associated vascular disorders, including varicose veinpathology.