In diabetes, especially type 2 diabetes, insulin resistance occurs when the body’s cells become less responsive to insulin’s action. This resistance affects multiple tissues, each at a different “action point” in glucose metabolism.
🔍 Main action points of insulin resistance:
1. Liver (Hepatic insulin resistance)
Normal insulin action: Suppresses hepatic glucose production (gluconeogenesis & glycogenolysis)
In insulin resistance:
🔺 Liver continues to produce glucose even when blood glucose is high
🔺 → Fasting hyperglycemia
2. Muscle (Skeletal muscle insulin resistance)
Normal insulin action: Stimulates glucose uptake via GLUT4 transporters
In insulin resistance:
🔻 Glucose uptake is impaired
🔻 Less glucose is stored as glycogen
🔻 → Postprandial hyperglycemia
3. Adipose tissue (Adipocyte insulin resistance)
Normal insulin action:
Suppresses lipolysis (fat breakdown)
Promotes fat storage
In insulin resistance:
🔺 Lipolysis is increased
🔺 More free fatty acids (FFA) are released into the blood
🔺 FFAs worsen hepatic insulin resistance and promote ketogenesis
4. Brain (Central insulin resistance, under debate)
Insulin may regulate appetite and energy balance in the hypothalamus
Resistance may impair satiety signaling, contributing to overeating and obesity
Vascular complications of diabetes: mechanisms of injury and protective factors Christian Rask-Madsen and George L. King Cell Metab. 2013 Jan 8; 17(1): 20–33. doi: 10.1016/j.cmet.2012.11.012 Overproduction of reactive oxygen species (ROS) as a result of altered glucose metabolism and formation of advanced glycation end-products (AGE) further amplifies this process by activating nuclear factor κB (NFκB) and other proinflammatory pathways.
W Henle, G Henle. INTERFERENCE OF INACTIVE VIRUS WITH THE PROPAGATION OF VIRUS OF INFLUENZA Science . 1943 Jul 23;98(2534):87-9. doi: 10.1126/science.98.2534.87.
In 1957, Alick Isaacs (1921–1965) and a post-doctoral Swiss student, Jean Lindenmann, were studying the phenomenon of “viral interference”—the ability of one virus to inhibit the replication of another virus. When 10-day-old chick chorioallontoic membranes from chick embryos were infected with heat or UV inactivated influenza virus, a material was produced that interfered with subsequent viral replication. (Interferons by Milton W. Taylor)
Interferons by Milton W. Taylor. Viruses and Man: A History of Interactions. 2014 Jul 22 : 101–119. Published online 2014 Jul 22. doi: 10.1007/978-3-319-07758-1_7 PMCID: PMC7123835
Isaacs, A., Lindenmann, J. (1957). Virus interference. I. The interferon. Proceedings of the Royal Society of London Series B, Containing papers of a Biological character Royal Society, 147(927), 258–267.
インターフェロンγは細胞傷害性T細胞によるがんゲノムの免疫エディティングに必要である IFN-γ is required for cytotoxic T cell-dependent cancer genome immunoediting 2017年2月24日 Nature Communications 8 : 14607 doi: 10.1038/ncomms14607
インターフェロンに関するセミナー動画
Hertzog P (2014): Interferon Signalling WEHI Seminars (Walter and Eliza Hall Institute Postgraduate lecture 14 April 2014 Professor Paul Hertzog Monash Institute of Medical Research)