GCG and Insulin resistance: The mechanisms by which CHM treat diabetes include the following: (1) CHM increase insulin sensitivity and ameliorate insulin resistance; (2) CHM promote insulin secretion and elevate serum insulin levels; (3) CHM inhibit α-glucosidase activity; (4) CHM protect islet β cells and promote their regeneration; (5) CHM increase hepatic glycogen content and suppress gluconeogenesis; (6) CHM inhibit the secretion of glucagon; (7) CHM promote the glucose uptake by adipose and muscular tissues (Figure 4).