Blood sugar regulation cells in the pancreatic islets are among the most well understood and important. If the blood glucose level falls to dangerous levels (as during very heavy exercise or lack of food for extended periods), the alpha cells of the pancreas release glucagon, a hormone whose effects on liver cells act to increase blood glucose levels. They convert glycogen into glucose (this process is called glycogenolysis). The glucose is released into the bloodstream, increasing blood sugar. Hypoglycemia, the state of having low blood sugar, is treated by restoring the blood glucose level to normal by the ingestion or administration of dextrose
Genetic causes of diabetes mellitus type 2 like APOM and APM1 increase the risk of type 2 diabetes when there are SNPs in their proximal promoter regions. Promoters are sequences of DNA that allows proteins such as transcription factors to bind for gene expression, and when the sequences are modified, the proteins no longer bind as effectively, resulting in depressed level of gene expression. APOM is partly responsible for producing pre beta-high-density lipoprotein and cholesterol, and APM1 is responsible for regulating glucose level in blood and fatty acid. Decreasing the level these gene products reduce the body's ability to handle glucose, which leads to the increased risk