Glucoindole alkaloids from stem bark of Strychnos mellodora

Repaglinide (Prandin) and Nateglinide (Starlix), known as glinides, are oral insulin secretagogues that stimulate insulin release from pancreatic β cells by closing the ATP-sensitive potassium channels (KATP channel). Repaglinide controls insulin release from pancreatic β cells by managing potassium efflux. It shares two binding sites with sulfonylureas and also has a unique site, indicating overlapping mechanisms of action. With a rapid onset and a 4-7 hour duration, it effectively manages...

α-glucosidase inhibitors, including acarbose (Precose), miglitol (Glyset), and voglibose (Voglib) (primarily available in Asia), are drugs that control blood sugar levels by delaying the digestion of starch and disaccharides. They achieve this by inhibiting α-glucosidase enzymes in the intestine, which slow the absorption of carbohydrates in the intestine, which in turn leads to a prolonged release of the glucoregulatory hormone GLP-1 from intestinal L-cells.
Acarbose and miglitol are typically...

Sulfonylureas are oral hypoglycemic agents utilized in treating type 2 diabetes. They are characterized by their unique sulfonylurea chemical structure. The family of sulfonylureas is divided into generations. First-generation sulfonylureas, including tolbutamide (Orinase), chlorpropamide (Diabinese), and tolazamide (Tolinase), trigger insulin release from pancreatic β cells and enhance peripheral tissues' insulin sensitivity. The second-generation members, such as glipizide (Glucotrol),...

Cholinergic agonists or cholinomimetics mimic the action of acetylcholine to stimulate the parasympathetic nervous system. They are categorized into direct-acting and indirect-acting agents. The direct-acting cholinergic drugs induce the parasympathetic response by directly binding to the muscarinic or nicotine receptors. In comparison, the indirect-acting cholinergic drugs prevent acetylcholine hydrolysis, indirectly contributing to the extended parasympathetic response.
The direct-acting...

Direct-acting cholinergic agonists, such as synthetic choline esters and naturally occurring alkaloids, exert their effects by enhancing the actions of acetylcholine and stimulating the parasympathetic nervous system. Synthetic choline esters share structural similarities with acetylcholine. For example, they have a positively charged quaternary ammonium or onium group, contributing to their hydrophilic characteristics. As a result, they are poorly absorbed in the body through oral...

Biguanides, particularly metformin (Glucophage), are insulin sensitizers that enhance glucose uptake, thereby reducing insulin resistance. Unlike sulfonylureas, metformin doesn't prompt insulin secretion, which helps to curb hypoglycemia risk. Metformin is beneficial in treating conditions like polycystic ovary syndrome due to its insulin-resistance reduction capability. The drug's primary action involves curtailing hepatic gluconeogenesis, a significant contributor to high blood glucose levels...