Ⅲ.Regulate Blood Glucose by Pu’er Tea
Fig.6-7 Effect of Pu’er tea in lowering blood glucose
With the improvement of people’s living standard, diabetes has become one of the killers of the health of middle-aged and elderly people.The incidence of diabetes is increasing year by year, and it is now second only to accidental death and tumor death.Although there are many drugs for its treatment,most of them cannot cure it, and have strong side effects.Diabetes is metabolic disorder of protein and glucose caused by the relative or absolute deficiency of insulin due to immune dysfunction, genetic factors, etc., and the endocrine and metabolic disorder caused by acid-base imbalance.
Polyphenols, polysaccharides, pigments, etc.contained in tea are the main active ingredients to inhibit the rise of blood glucose.Tea polyphenols can protect islet β cells, improve insulin activity, promote insulin secretion, inhibit the activities of related enzymes in intestinal tract, control the activity of glucose transport carrier, and down-regulate the expression of gluconeogenesis genes.Tea polysaccharides can improve the antioxidant function, scavenge internal free radicals, weaken the damage of free radicals to islet β cells, improve the function of damaged islet β cells, increase insulin secretion, improve insulin sensitivity, induce the production of glucokinase, promote glucose decomposition and reduce blood glucose.Tea pigments can reduce blood glucose and blood lipid content by reducing plasma viscosity and fibrinogen,lowering cholesterol and triglyceride content, and increasing high-density lipoprotein content.
Li Zhiwen et al.treat diabetic rats with Pu’er tea soup extract by intragastric administration,and find that Pu’er tea extract can significantly reduce the fasting blood glucose, area under the blood glucose curve and fasting serum insulin of diabetic rats.Kong Lingbo et al.inject Pu’er tea polysaccharide compound solution into the abdominal cavity of diabetic mice, and find that Pu’er tea polysaccharides can reduce the blood glucose level of hyperglycemic mice induced by alloxan, and the Pu’er tea of high dose has better hypoglycemic effects than that of low dose.Tea polyphenols can regulate glucose metabolism and reduce blood glucose.Liu Junhui et al.have obtained Guangxi sweet tea polyphenols through water extraction and macroporous absorptive resins.With alloxan-induced diabetic mice as a model, they explore the effect of tea polyphenols on diabetic mice, and find that sweet tea polyphenols can reduce blood glucose and improve glucose tolerance of diabetic mice.Tea polysaccharide is another important physiological active substance discovered after tea polyphenols.Chen Jianguo et al.extract tea polysaccharides from old tea leaves by extraction method, and find that the tea polysaccharides can effectively reduce blood glucose and improve diabetic symptoms and glucose tolerance of diabetic mice.With the increase of tea polysaccharides, the contents of serum insulin and liver glycogen also increase significantly.At the same time, it can repair the damage of endoplasmic reticulum, mitochondria and other structures of islet β cells, increase zymogen granules, and improve and restore cell secretion and other functions.Tea pigments can improve the diabetic patients’ability of controlling blood glucose.Xu Xiangting et al.treat diabetic mice with continuous intragastric administration of theabrownin, and find that theabrownin in fermented Pu’er tea has the effects of reducing fasting blood glucose, fasting insulin level and improving glucose metabolism of diabetic mice, with a dose-effect relationship.