Normal immune response is the main mechanism for the body to maintain its own balance and resist foreign aggression, while excessive immune response will cause various autoimmune diseases, allergies and inflammatory reactions. Immunosuppressive drugs treat related diseases by inhibiting immune response. However, if this inhibition lacks selectivity to cells and tissues, leading to the overall inhibition of immune response, it will have serious toxic and side effects. Professor Xu Qiang's research group of Nanjing University has done a lot of research on selective immunosuppression of astilbin and achieved many original results. It was found that astilbin could significantly inhibit delayed hypersensitivity, collagen arthritis and immune liver injury. Compared with cyclosporine A, astilbin has a more selective immunosuppressive effect. Astillyrin inhibits excessive cellular immunity without affecting humoral immunity, and its functional characteristics can be summarized as follows: ① selectively inhibits the effective period of the disease without affecting the induction period; ② Selective inhibition of activated T cells without affecting normal T cells and other tissue cells; ③ Selective inhibition of activated Th 1 cells without affecting Th2 cells. Its molecular mechanism is to induce apoptosis of activated T cells through mitochondrial pathway, including opening voltage-dependent anion channels on mitochondrial membrane, disintegrating mitochondrial transmembrane potential, releasing cytochrome C and promoting caspase cascade reaction. In addition, the negative regulation of cytokines is an important link in the selective immunosuppression of astilbin. Other drugs or compounds with similar selective immune characteristics have not been reported. The potential clinical significance of astilbin deserves further attention, and it is expected to achieve the same therapeutic effect and avoid the adverse reactions of long-term medication for chronic immune diseases.
2. Regulate the metabolism of fat and cholesterol
Motoyashiki and other studies have found that astilbin can increase the intracellular cAMP concentration of mouse adipose tissue and increase the activity of lipoprotein lipase, thus accelerating lipolysis. Chen et al. used African green monkey kidney cells as a model, and found that astilbin could inhibit the activity of rate-limiting enzyme HMG-CoA reductase in the process of cholesterol synthesis in the screening of more than 40 flavonoids. With HepG2 cells as the model, Theriault and other studies found that taxifolin could effectively inhibit the synthesis and esterification of cholesterol, the synthesis of triglycerides and phospholipids. This effect is related to the decrease of apolipoprotein B and the increase of apolipoprotein A-I secretion. Further research shows that taxifolin can inhibit the activities of diacylglycerol acyltransferase and microsomal triglyceride transporter in HepG2 cells, reduce the synthesis of triglycerides, and thus reduce the secretion of apolipoprotein B.
3. Antioxidant effect
Astillyrin has strong antioxidant capacity, which can effectively scavenge free radicals such as DPPH, ABTS and superoxide anion, and inhibit linoleic acid peroxidation. Its effect is equivalent to that of synthetic antioxidants BHA and BHT, and it is expected to become a new natural food antioxidant. Petacci and other studies have found that astilbin can inhibit the activities of myeloperoxidase and horseradish peroxidase, and can effectively remove hypochlorous acid. In the mouse liver injury model induced by carbon tetrachloride, astilbin can significantly reduce the liver lipid peroxidation and induce the activity of superoxide dismutase to increase, thus playing a protective role against liver injury, and the effect is stronger than ve.
4. Hypoglycemic effect
Haraguchi et al found that astilbin and its aglycone-taxifolin inhibited the accumulation of aldose reductase and sorbitol, revealing that it could prevent osmotic stress caused by hyperglycemia. Wirasathien et al. measured the IC50 of astilbin inhibiting aldose reductase, and its value was 26.7 microns ... Advanced glycation end products (AGEs) were formed by combining some reducing sugars (such as glucose and fructose) with amino acids through a series of reactions such as non-enzymatic saccharification, lipid oxidation and structural rearrangement. AGEs is closely related to the occurrence and development of diabetes and its complications. Astillyrin can inhibit the formation of AGEs, and its effect is the same as quercetin. Glucose -6- phosphatase is one of the two key enzymes in liver gluconeogenesis. Studies have shown that the activity of glucose -6- phosphatase is closely related to insulin resistance and diabetic hyperglycemia, which may become a potential target of diabetic drugs. Estrada and other studies found that astilbin could inhibit glucose -6- phosphatase, and its IC50 was 959μM, which was lower than that of quercetin1330 μ m. Fukunaga and other studies showed that the methanol extract of Smilax glabra could significantly reduce the blood sugar concentration of non-insulin-dependent diabetic mice, but had no effect on insulin-dependent mice, revealing that Smilax glabra extract could induce and enhance insulin activity to achieve the effect of lowering blood sugar.
5, bacteriostatic and insecticidal effects
Moulari et al. found that the antibacterial effect of the extract from leaves of Haluga Madagascar originated from astilbin. Astillyrin has a significant inhibitory effect on gram-negative bacteria such as Acinetobacter. And Moraxella. And positive bacteria such as micrococcus and staphylococcus aureus, and the minimum inhibitory dose is 25-75 μ g..Cintra and other studies have found that astilbin has a killing effect on leaf-cutting ant worker ants (Attasexdensrubropilosa). The mortality rate of worker ants in the feed group containing astilbin was significantly higher than that in the control group. Pereira et al. studied the insecticidal effect of astilbin on soybean pests, namely Spodoptera litura and apple borer. The results showed that astilbin could reduce its survival rate and prolong the development time of larvae and pupae.
6. Inhibit the proliferation of cancer cells and induce apoptosis.
Astillyrin can inhibit the proliferation of HepG2, Hela, HL-60 and other cancer cells, with IC50 values of 0.47, 0.26 and 0.45mg/mL(24h) respectively. The methanol extract of Rhizoma Smilacis Glabrae with astilbin as the main component can also inhibit the proliferation of HepG2 cells, and the IC50 value is 1. 1mg/mL(48h), and it can induce the apoptosis of cancer cells through mitochondrial-mediated pathway. Astillyrin can inhibit proliferation and induce apoptosis in human breast cancer MCF-7 and MDA-MB-23 1 cells, with IC50 values of 18.0 and 20.8μg/mL, respectively.
7. Promote hair growth
Astillyrin can promote hair growth, and Kao Company of Japan applied for related patents with it as the main formula. 3,4'-dimethyl -3- hydroxyflavanone produced by chemical modification of astilbin is more effective and can effectively prevent male hair loss. Japan has approved it as a tonic for hair repair.