Lipid and Blood Pressure Lowering Effects of Mikania micrantha Through En-zymatic Inhibition

Abstract

Mikania micrantha Kunth (Asteraceae) is a plant traditionally used to reduce the risk of hyperlipidemia and hypertension. There is limited information on the anti-hyperlipidemic and anti-hypertensive effects of the various M. micrantha leaves and stem extracts. This study aimed to examine the in vitro potential of different parts of M. micrantha (leaves and stem) extracts in inhibiting hyperlipidemia-related enzymes, i.e., pancreatic lipase (PL), lipoprotein lipase (LPL) and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR), in addition to the hypertension-related, i.e., angiotensin-I converting enzyme (ACE). This study spectrophotometrically determined the inhibitory activities of hot water, cold water, 70% ethanol, and ethyl acetate M. micrantha leaves and stem extracts against the above-said enzymes using PL, LPL, HMGR, and ACE inhibition assays. The study found that the ethanol stem (ETS) extract exhibited the highest PL inhibitory activity (IC50=4.49±2.50 μg/mL), albeit the difference was insignificant (p > 0.05) compared to orlistat (IC50=0.31±0.01 μg/mL). Meanwhile, the ethanol leaves (ETL) extract yielded the highest LPL (IC50=1.42±0.48 μg/mL) and HMGR inhibitory activity (50.12±3.44%), although the greatest ACE inhibition was observed for the hot water stem (HWS) extract (97.47±1.19%). However, the result was insignificant (p > 0.05) compared to other extracts and captopril (98.42±0.93%). In brief, the extracts generally exhibited remarkable inhibitory activity against PL, LPL, HMGR, and ACE, thus conveying the M. micrantha extracts' anti-hyperlipidemic and anti-hypertensive potentials.

In Silico Analysis of Selected Mikania Constituents As Human HMG-CoA Reductase, Human Inducible Nitric Oxide Synthase, and Human Squalene Synthase Inhibitory Agents

“…Earlier, three phytoconstituents, namely curcumin from the Curcuma longa plant, docosanol from the Saccharum arundinaceum plant, and salvianolic acid C from the Salvia miltiorrhiza plant were demonstrated to suppress HMGR enzyme activity [14]. Recently, crude leaf and stem extracts of M. micrantha were reported to inhibit HMGR enzyme activity [12,15]. However, in the current investigation, 21 ligands of Mikania, namely MM, KAA, SS, GA, KA, SP, CO, SA, DC, TA, ME, PA, THTMF, DMQ, BCG, BI, EL, PR, DHL, MS, and NE, failed to dock with hHMGR.…”

“…Crude leaf and flower extracts of M. micrantha have been reported to inhibit cyclooxygenase (COX), lipoxygenase (LOX), inducible nitric oxide synthase (iNOS), myeloperoxidase, and protease enzyme activities [11]. Similarly, crude leaf and stem extracts of M. micrantha have been reported to inhibit angiotensin-1 converting enzyme (ACE), 3-hydroxy-3methylglutaryl-coenzyme A reductase (HMGR), lipoprotein lipase (LPL), and pancreatic lipase (PL) enzyme activities [12]. Based on the above-mentioned information, we carried out the current work to analyze 26 chosen constituents (present in the whole plant, which are common among the Mikania species) of Mikania…”