Endogenous is the opposite of exogenous, which means originating outside a living organism. Some exogenous substances are harmful, while others are used as medications or supplements to imitate or counteract the action of endogenous substances. This is a common method of disease treatment.
This article describes some common endogenous substances, some of which also have exogenous counterparts.
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Examples of Endogenous Substances
Here are several examples of endogenous substances:
Endogenous Cholesterol
While endogenous and exogenous cholesterol can both be beneficial—these substances can be harmful if you consume too much or if your body makes too much.
Endogenous Opioids
Your body can manufacture its own pain relief in the form of endogenous opioid compounds. In fact, your brain actually activates these self-manufactured drugs to prevent pain in certain cases—this is the physical mechanism behind the “runner’s high.”
Endogenous Autoantibodies
Your immune system is designed to fight against foreign invaders like viruses and bacteria. Sometimes, though, the immune system makes antibodies that mistakenly attack a person’s own organs and other tissues.
These endogenousautoantibodiesoriginate within the body and are called “auto” antibodies because they’re attacking their own organism. People who have this type of immune malfunction can develop autoimmune diseases such asceliac disease(where the endogenous autoantibodies attack the small intestine) or type 1 diabetes (where they attack the pancreas).
For some autoimmune conditions, like rheumatoid arthritis, anti-inflammatory medications that dampen the endogenous immune system function can alleviate symptoms. But in other autoimmune diseases, like celiac disease and diabetes type 1, inflammatory suppression won’t help because the immune system actually damages tissue. Other treatments, like dietary modification for celiac disease or insulin for diabetes, are needed instead.
Endogenous Hydrogen Sulfide
Medical researchers have investigated what triggers this problem, and have pinpointed several potential culprits. One of these is endogenous hydrogen sulfide.This irritant material is present in the environment, and your body can make it too.
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A Word From Verywell
You may frequently hear the names of exogenous substances that also have endogenous forms. Normally, your body does a pretty good job of balancing out different endogenous functions and substances, and sometimes outside interventions are needed to help.
3 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Cancer Institute.NCI Dictionary of Cancer Terms: Endogenous. National Cancer Institute.Corliss J.How it’s made: Cholesterol production in your body. Harvard Health.Liao YX, Wang XH, Bai Y, Lin F, Li MX, Mi WJ, Sun WL, Chen YH.Relationship between endogenous hydrogen sulfide and pulmonary vascular indexes on high resolution computed tomography in patients with chronic obstructive pulmonary disease.Int J Chron Obstruct Pulmon Dis. 2021 Aug 10;16:2279-2289. doi:10.2147/COPD.S314349Additional ReadingHolden JE et al. The endogenous opioid system and clinical pain management. AACN Clinical Issues; 16(3):291-301.Nijs L et al.Dysfunctional endogenous analgesia during exercise in patients with chronic pain: to exercise or not to exercise?Pain Physician; 15(3 Suppl):ES205-13.
3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Cancer Institute.NCI Dictionary of Cancer Terms: Endogenous. National Cancer Institute.Corliss J.How it’s made: Cholesterol production in your body. Harvard Health.Liao YX, Wang XH, Bai Y, Lin F, Li MX, Mi WJ, Sun WL, Chen YH.Relationship between endogenous hydrogen sulfide and pulmonary vascular indexes on high resolution computed tomography in patients with chronic obstructive pulmonary disease.Int J Chron Obstruct Pulmon Dis. 2021 Aug 10;16:2279-2289. doi:10.2147/COPD.S314349Additional ReadingHolden JE et al. The endogenous opioid system and clinical pain management. AACN Clinical Issues; 16(3):291-301.Nijs L et al.Dysfunctional endogenous analgesia during exercise in patients with chronic pain: to exercise or not to exercise?Pain Physician; 15(3 Suppl):ES205-13.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
National Cancer Institute.NCI Dictionary of Cancer Terms: Endogenous. National Cancer Institute.Corliss J.How it’s made: Cholesterol production in your body. Harvard Health.Liao YX, Wang XH, Bai Y, Lin F, Li MX, Mi WJ, Sun WL, Chen YH.Relationship between endogenous hydrogen sulfide and pulmonary vascular indexes on high resolution computed tomography in patients with chronic obstructive pulmonary disease.Int J Chron Obstruct Pulmon Dis. 2021 Aug 10;16:2279-2289. doi:10.2147/COPD.S314349
National Cancer Institute.NCI Dictionary of Cancer Terms: Endogenous. National Cancer Institute.
Corliss J.How it’s made: Cholesterol production in your body. Harvard Health.
Liao YX, Wang XH, Bai Y, Lin F, Li MX, Mi WJ, Sun WL, Chen YH.Relationship between endogenous hydrogen sulfide and pulmonary vascular indexes on high resolution computed tomography in patients with chronic obstructive pulmonary disease.Int J Chron Obstruct Pulmon Dis. 2021 Aug 10;16:2279-2289. doi:10.2147/COPD.S314349
Holden JE et al. The endogenous opioid system and clinical pain management. AACN Clinical Issues; 16(3):291-301.Nijs L et al.Dysfunctional endogenous analgesia during exercise in patients with chronic pain: to exercise or not to exercise?Pain Physician; 15(3 Suppl):ES205-13.
Holden JE et al. The endogenous opioid system and clinical pain management. AACN Clinical Issues; 16(3):291-301.
Nijs L et al.Dysfunctional endogenous analgesia during exercise in patients with chronic pain: to exercise or not to exercise?Pain Physician; 15(3 Suppl):ES205-13.
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