Combination of spices and herbal extract restores macrophage foam cell migration and abrogates the athero-inflammatory signalling cascade of atherogenesis

The trapping of lipid-laden macrophages in the arterial intima is a critical but reversible step in atherogenesis. However, information about possible treatments for this condition is lacking. Here, we hypothesized that combining the polyphenol-rich fractions (PHC) of commonly consumed spices (Allium sativum L (Liliaceae), Zingiber officinale R (Zingiberaceae), Curcuma longa L (Zingiberaceae)) and herbs (Terminalia arjuna (R) W & A (Combretaceae) and Cyperus rotundus L (Cyperaceae)) prevents foam cell formation and atherogenesis. Using an in vitro foam cell formation assay, we found that PHC significantly inhibited lipid-laden macrophage foam cell formation compared to the depleted polyphenol fraction of PHC (F-PHC). We further observed that PHC attenuated the LDL and LPS induced CD36, p-FAK and PPAR-γ protein expression in macrophages and increased their migration. NK-κB-DNA interaction, TNF-α, ROS generation, and MMP9 and MMP2 protein expression were suppressed in PHC-treated macrophages. The anti-atherosclerotic activity of PHC was investigated in a high fat- and cholesterol-fed rabbit model. The inhibition of foam cell deposition within the aortic intima and atheroma formation confirmed the atheroprotective activity of PHC. Therefore, we conclude that the armoury of polyphenols in PHC attenuates the CD36 signalling cascade-mediated foam cell formation, enhances the migration of these cells and prevents atherogenesis.

Validation of therapeutic anti-inflammatory potential of Arjuna Ksheera Paka - A traditional Ayurvedic formulation of Terminalia arjuna

Arjuna Ksheera Paka (AKP), a traditional Ayurvedic formulation of Terminalia arjuna (T. arjuna) bark powder is used for its cardioprotective effects. However, its anti-inflammatory efficacy remained unexplored. In the present study, AKP was prepared in cow milk (as per standard Ayurvedic procedure) and compared with standard hydroalcoholic extract (HA) of T. arjuna. The extracts were analyzed for gross phytoconstituents levels, and their antioxidant activity was assayed by DPPH free radical scavenging activity and inhibition of lipid peroxidation. The in vivo anti-inflammatory activity of AKP and HA was studied in carrageenan-induced hind paw biphasic edema in C57BL/6 mice (at 200, 400 and 800 mg/kg BW). The percentage extraction yield of AKP was two folds higher than HA implying that the phytoconstituents in AKP were diluted by a factor of 0.5. The total polyphenol content of HA was (3.8 times) higher than AKP and the antioxidant activity of HA was also higher compared to AKP. Both the extracts, however, showed significant (p < 0.05) anti-inflammatory activity in reducing paw edema in mice. The efficacy of HA was more than AKP at early phase of inflammation, whereas, in the late phase of inflammation AKP was more efficacious and equipotent to HA. Thus, regardless of low in vitro antioxidant activity, AKP exhibited potential in vivo anti-inflammatory activity. The higher efficacy of AKP could be due to the presence of milk solids. These milk solids may act as adjuvants to T. arjuna's phytoconstituents, contributing to their sustained bioavailability, leading to higher in vivo anti-inflammatory efficacy at lower drug concentrations.