Highly Oxygenated Labdane Diterpenoids from Stevia rebaudiana and Their Anti‐Atherosclerosis Activities

Abstract

Five unknown labdane diterpenoids Stevelins A -E (1 -5), three known labdane diterpenoids (6 -8) and three labdane norditerpenoids (9 -11) were isolated from the Stevia rebaudiana. The structures were determined primarily via NMR spectroscopic data and HR-ESI-MS experiments. X-ray crystallography using CuK α radiation was used to determine the absolute configurations of 1, and the absolute configurations of 2-5 were deduced by electronic circular dichroism (ECD) calculations. The potential anti-atherosclerosis activities of all compounds were evaluated by measuring their inhibitory effects on the macrophage foam cell formation. As a result, most isolated compounds could significantly inhibit oxidized low-density lipoprotein (ox-LDL)-induced macrophage foam cell formation, which suggests that these compounds may be promising candidates in the treatment for atherosclerosis.

A Comprehensive Review of the Classification, Sources, Phytochemistry, and Pharmacology of Norditerpenes

“…Compound 364 inhibited the acetyl transfer activity of M. tuberculosis GlmU, with an IC 50 value of 41.85 μM, representing a novel therapeutic target for tuberculosis [ 120 ]. Compound 371 can significantly inhibit the formation of macrophage foam cells induced by oxidized low-density lipoprotein, suggesting its potential as a protective agent against atherosclerosis [ 134 ]. Compounds 454 – 456 displayed antifobrotic activities on TGF- β 1-induced rat renal proximal tubular cells, effectively attenuating the excessive production of collagen I and α -SMA [ 141 ].…”