Antioxidant, anti-proliferative, and anti-atherosclerotic effect of phytochemicals isolated from Trachyspermum ammi with honey in RAW 264.7 and THP-1 cells

Abstract

Background: Trachyspermum ammi is a common spice with vital medicinal properties used in Ayurveda to treat many ailments. Furthermore, natural Honey is said to have high levels of antioxidants and anti-inflammatory properties. While the combination of both T. ammi and Honey is unexplored in anti-atherosclerotic activity. Materials and Methods: Assays guided isolation of carotenoids, phenolics, and tannins were performed by methanol and aqueous extraction from T. ammi seed powder and honey mixture. Phytochemical screening for antioxidant activity (superoxide radical scavenging activity, nitric oxide radical scavenging activity, and 2, 2-diphenyl-1-picrylhydrazyl scavenging activity) and antilipidemic activity by inhibition of low-density lipoprotein (LDL) oxidation were investigated. Sample showing highest activity with lowest IC50 value from antioxidant and antilipidemic activity was further evaluated on RAW 264.7, THP-1 cells for foam cell inhibition activity, anti-proliferation, antiapoptotic activity, and nitric oxide assay. The sample was characterized using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). Results: Out of the phytochemicals screened, tannin methanol extract (TME) showed the highest antioxidant activity with IC50 value having 7.11 μg/mL in superoxide scavenging assay, the IC50 value of 1.46 μg/mL by nitric oxide scavenging assay, and followed by IC50 value of 20.83 μg/mL in 2, 2-diphenyl-1-picrylhydrazyl activity. The results showed that it also efficiently inhibited LDL oxidation at 240 μg/mL (71.29% at 5 h)., thus inhibiting foam cell development, preventing proliferation, apoptosis, and nitrate production in cultured RAW 264.7 and THP-1 cells. HPLC analysis showed the presence of tannin in the extract. TME was characterized in GC-MS, which showed 13 prominent compounds. Conclusion: The scientific evidence in the present study showed that the TME from T. ammi seed powder and honey act as an antioxidant and antiatherogenic properties in inhibiting foam cell formation. Hence, this phytochemical can be used for the treatment of atherosclerosis.