Asian plantain (Plantago asiatica) essential oils suppress 3-hydroxy-3-methyl-glutaryl-co-enzyme A reductase expressionin vitroandin vivoand show hypocholesterolaemic properties in mice

Abstract

Asian plantain (Plantago asiatica) essential oil (PAEO) contains multiple bioactive compounds, but its potential effects on lipid metabolism have not been examined. PAEO was found to be mostly composed of oxygenated monoterpenes, with linalool as the major component (82·5 %, w/w), measured using GC -MS. Incubation of 0 -200 mg PAEO/ml with HepG2 cells for 24 h resulted in no significant toxicity. Incubation with 0·2 mg PAEO/ml altered the expression of LDL receptor (þ 83 %; P,0·05) and 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase (2 37 %; P, 0·05), as assessed using RT-PCR. LDL oxidation was markedly inhibited by PAEO treatment due to the prevalence of linalool compounds in PAEO. Oral administration of PAEO for 3 weeks in C57BL/6 mice significantly reduced plasma total cholesterol and TAG concentrations by 29 and 46 %, respectively. The mRNA (þ58 %; P, 0·05), but not protein, levels of the LDL receptor were significantly higher, whereas both mRNA and protein levels of HMG-CoA reductase were significantly lower (246 and 211 %, respectively; P,0·05) in the liver of PAEO-fed than of control mice. The mRNA levels of CYP7A1 were marginally reduced in HepG2 cells, but not in mouse liver after PAEO treatment. Thus, PAEO may have hypocholesterolaemic effects by altering the expression of HMG-CoA reductase. Reduced TAG and oxidised LDL may provide additional cardiovascular protective benefits.Plantago asiatica: Essential oils: Cholesterol: 3-Hydroxy-3-methyl-glutaryl-co-enzyme A reductase: Low-density lipoprotein-receptor: Triacylglycerols CHD is a major cause of death in developed societies 1 . Elevated LDL-cholesterol and TAG levels are both independent risk factors for CHD 2 -4 . In addition, the presence of oxidised LDL accelerates atherogenesis 5,6

A Brief Overview of the Effects of Melissa officinalis L. Extract on the Function of Various Body Organs

“…Among effective pharmacological agents in treating these diseases, we can refer to statins, clofibrates and niacin. However, in general these compounds are not effective in reducing cholesterol concentration and are often associated with adverse effects and drug toleration, [12][13][14][15][16][17][18][19]. Therefore, all efforts have been concentrated on prevention strategies like phytochemical diet.…”

“…Terpenoids are among the essential compounds in herbal oils that induce hypolipidemic effects by inhibiting liver biosynthesis and formation of cholesterol nucleus in bile. Studies have shown that the essential oil compounds of Plantago asiatica inhibit mRNA and protein expression of HMG-COA reductase in HePG2 cells and C57BL/6 cells in rats [19].…”

Melissa officinalisEssential Oil Reduces Plasma Triglycerides in Human Apolipoprotein E2 Transgenic Mice by Inhibiting Sterol Regulatory Element-Binding Protein-1c–Dependent Fatty Acid Synthesis3

“…Terpenoids from herbal essential oils produced hypolipidemic effects by inhibiting hepatic cholesterol biosynthesis and cholesterol nucleation in bile. We showed that Plantago asiatica essential oil suppressed the mRNA and protein expression of HMG-CoA reductase in both HepG2 cells and C57BL/6J mice (8); that MOEO 4 produced antidiabetic effects, improving glucose tolerance and regulating the hepatic expression of genes involved in gluconeogenesis (9); and that wormwood (Artemisia princeps) essential oil displayed potent antioxidative and hypocholesterolemic activities (10). Among plant sources of essential oils, MO is a well-known medicinal herb that has been used for a long time and has been suggested to be effective in the treatment of multiple conditions, including headaches, gastrointestinal disorders, nervousness, and rheumatism (11).…”

“…On average, a cup of MO tea (0.15 L) contains~10 mg/L of essential oil (14); accordingly, drinking 2-3 cups of MO tea (0.3-0.45 L) daily may improve metabolic parameters such as plasma cholesterol and TG levels in humans (9). Evidence exists that herbal essential oils have various pharmacological effects that can be attributed to the volatile and terpenoid compounds they contain, which include geranial, cineol, linalool, and caffeic acid (8)(9)(10)16).…”

Korean Red Ginseng Extract Suppresses the Progression of Alcoholic Fatty Liver in a Rat Model

“…Researches are ongoing to define the preventive and curative properties of these natural materials such as Hoveniadulcis, 1) Plantagoasiatica L. seeds, 2) and the fruits of Chrysanthemum indicum Linné, 3) Meliatoosendan fruit, 4) and Schisandrachinensis Baill. 5) Above all, Korean ginseng, the root of Panax ginseng, has been prescribed as the most precious folk medicine in many oriental nations.…”