Views: 1 Author: 菌物健康 Publish Time: 2022-10-26 Origin: Site
Inonotus obliquus, also known as Chaga, is a large edible fungus with the same origin of medicine and food. It is widely distributed in temperate continents between 40° and 50° north latitude and in Russia, the United States, Finland, Poland, China and Japan with temperate monsoon climates, etc. country / region. It has been used for more than 400 years since the beginning of the 16th century. Inonotus obliquus is rich in active ingredients such as polysaccharides, polyphenols, triterpenes, melanin and lignin, and has the functions of lowering blood lipids, lowering blood sugar, anti-tumor, antioxidant and anti-virus and other pharmacological effects. Since the 21st century, a large number of research reports on Inonotus obliquus have emerged, and the pharmacological effects and mechanisms of its active ingredients have been more clearly explained, and more discoveries have been made on the composition of Inonotus obliquus. In this paper, the research on blood lipid lowering of Inonotus obliquus at home and abroad in recent years was reviewed, and the active components and mechanism of Inonotus obliquus in lowering blood lipids were preliminarily explained.
Lipid-lowering active ingredients
1. Polysaccharides
Inonotus obliquus polysaccharides are mainly composed of monosaccharides linked by glycosidic bonds such as galactose, glucose, mannose, rhamnose, arabinose, glucuronic acid and galacturonic acid, and are mainly acidic polysaccharides. Polysaccharides linked by glycosidic bonds usually have a vertical triple helix structure, which can combine with bile salts to reduce the reabsorption efficiency of bile acids and reduce the content of cholesterol.
2. Flavonoids
The flavonoids in Inonotus obliquus are mainly flavonoid glycosides composed of quercetin, naringenin, kaempferol and isorhamnetin. These flavonoid glycosides have multiple phenolic hydroxyl groups, and the multiple phenolic hydroxyl groups substituted on the A and B rings form a stable p-conjugated system with the benzene ring skeleton, so they have anti-lipid peroxidation, scavenging active free radicals and It exerts the antioxidant activity of flavonoids by affecting the enzymes in the body.
3. Polyphenols
Polyphenols are widely present in the roots, stems, leaves, bark and fruits of plants, and most of the plant polyphenols show different degrees of anti-lipid peroxidation ability. Different from flavonoids, the lipid-lowering effects of various polyphenolic monomers isolated from Inonotus obliquus, such as caffeic acid, gallic acid and p-coumaric acid, are mostly manifested in the improvement of liver lipids.
4. Triterpenes
The triterpenoids in Inonotus obliquus are mainly lanolin-type triterpenes and lupin-type triterpenes. Lanolin-type triterpenes can improve blood circulation and lower blood cholesterol. Inonotinol is a lanolin-type triterpenoid unique to Inonotus obliquus. In the treatment of streptozotocin (STZ)-induced diabetes in mice, Inonotinol can effectively regulate blood lipids TC, TG and HDL levels, and effectively repair STZ-induced abnormal levels of catalase (CAT), SOD, GSHPx and MDA in the blood of mice.
lipid-lowering mechanism
1. Antioxidant pathway
Inonotus obliquus polysaccharide can effectively improve the activities of CAT, GSH-Px and SOD in liver and kidney tissues of diabetic mice, and improve the ability to remove lipid peroxides. In addition, some studies have also shown that polysaccharides of Inonotus obliquus mycelia can effectively inhibit endogenous lipid peroxidation and cysteine-induced lipid peroxidation. - The signal transduction pathways and transcription factors expressed by Px and SOD had a certain effect, which increased the expression level of antioxidant enzymes.
2. Inhibit fat synthesis
Peroxisome proliferator-activated receptor (PPAR-) is an essential receptor for adipose tissue accumulation. PPAR- is highly present in adipose tissue, and its activation and expression induces adipose synthesis. SREBP is an important family of transcription factors that regulate lipid synthesis and is involved in the entire process of cholesterol and fatty acid synthesis. Glycerol phosphate transacylase (GPAT) and diacylglycerol transacylase (DGAT) catalyze the synthesis of lysophosphatidic acid from phosphoglycerol and the synthesis of TG from diacylglycerol, respectively, which are the key enzymes in the first and last steps of TG biosynthesis. Acetyl-CoA carboxylase (Acc) activates the substrate acetyl-CoA to synthesize fatty acids. Fas is involved in the entire process of FFA synthesis. Inonotus obliquus ethanolic extract (IOE) significantly inhibited the activities of PPAR- , SREBP1c, GPAT, DGAT, Acc and Fas in hyperlipidemia mice, and significantly decreased the serum levels of FFA, TC and TG in mice.
3. Promote fat conversion
Carnitine fatty acyltransferase I (CPT-1) is the key enzyme for the entry of long-chain fatty acyl-CoA into mitochondria for oxidation, and the level of fatty acyl-CoA in mitochondria is the main rate-limiting step of fatty acid-oxidation, so the level of CPT-1 The increase can effectively accelerate the fatty acid-oxidation process. In addition, both aldehyde oxidase (AOX) and peroxisome proliferator-activated receptor-coactivator-1 (PGC1) can accelerate the process of fatty acid-oxidation. A water-soluble melanin complex extracted from Inonotus obliquus can effectively upregulate CPT-1, AOX and PGC1 expression in epididymal adipose tissue of high-fat-fed mice and accelerate the hydrolysis of free fatty acids (FFA).
4. Increase fat consumption
High-fat diet can inhibit the level of citrate synthase in the body, which may be the key reason for the inhibition of the tricarboxylic acid cycle (TCA cycle) in patients with hyperlipidemia. One of the key reactions in . The TCA cycle is the final metabolic pathway of sugar, fat and amino acids. The final product of these three nutrients, acetyl CoA, enters the TCA cycle and is the main material for the body's energy material ATP generation. Through the analysis of urinary metabolites in mice fed a high-fat diet, Inonotus obliquus polysaccharide significantly improved the inhibitory effect of high-fat diet on TCA cycle, and accelerated the hydrolysis of endogenous substances and fat by increasing the level of TCA cycle, increasing the energy consumption.
5. Regulate the distribution of fat
Fatty acid transportase (Fat) and fatty acid transporter protein (Fatp) are highly expressed in mammalian adipose tissue. Fat promotes the transport of FFA into serum, and inhibition of Fatp levels redistributes FFA to liver tissue and promotes FFA uptake. The expression levels of Fat and Fatp in the liver fat of hyperlipidemic mice ingested with IOE were significantly reduced, which effectively adjusted the distribution and absorption balance of FFA in the liver and serum, and effectively reduced the serum FFA level in hyperlipidemic mice.
