Editing Homeostasis (section)

==Clinical significance==
Many diseases are the result of a homeostatic failure. Almost any homeostatic component can malfunction either as a result of an [[genetic disorder|inherited defect]], an [[inborn error of metabolism]], or an acquired disease. Some homeostatic mechanisms have inbuilt redundancies, which ensures that life is not immediately threatened if a component malfunctions; but sometimes a homeostatic malfunction can result in serious disease, which can be fatal if not treated. A well-known example of a homeostatic failure is shown in [[Diabetes mellitus type 1|type 1 diabetes mellitus]]. Here [[blood sugar regulation]] is unable to function because the [[beta cells]] of the [[pancreatic islets]] are destroyed and cannot produce the necessary [[insulin]]. The blood sugar rises in a condition known as [[hyperglycemia]].<ref>{{Citation |last1=Mouri |first1=MIchelle |title=Hyperglycemia |date=2023-04-24 |work=StatPearls |url=https://www.ncbi.nlm.nih.gov/books/NBK430900/ |access-date=2025-01-11 |place=Treasure Island (FL) |publisher=StatPearls Publishing |pmid=28613650 |last2=Badireddy |first2=Madhu}}</ref>

The plasma ionized calcium homeostat can be disrupted by the constant, unchanging, over-production of [[parathyroid hormone]] by a parathyroid [[adenoma]] resulting in the typically features of [[hyperparathyroidism]], namely high plasma ionized Ca<sup>2+</sup> levels and the resorption of bone, which can lead to spontaneous fractures. The abnormally high plasma ionized calcium concentrations cause conformational changes in many cell-surface proteins (especially ion channels and hormone or neurotransmitter receptors)<ref name=CMArmstrong1999>{{cite journal | vauthors = Armstrong CM, Cota G | title = Calcium block of Na<sup>+</sup> channels and its effect on closing rate | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 96 | issue = 7 | pages = 4154–7 | date = Mar 1999 | pmid = 10097179 | pmc = 22436 | doi = 10.1073/pnas.96.7.4154 | bibcode = 1999PNAS...96.4154A | doi-access = free }}</ref> giving rise to lethargy, muscle weakness, anorexia, constipation and labile emotions.<ref name=harrison>{{cite book | last1 = Harrison|first1= T.R. | title =Principles of Internal Medicine | edition=  third | pages = 170, 571–579 | location = New York | publisher =  McGraw-Hill Book Company}}</ref>

The body water homeostat can be compromised by the inability to secrete [[Antidiuretic hormone|ADH]] in response to even the normal daily water losses via the exhaled air, the [[feces]], and [[Dehydration#Cause|insensible sweating]]. On receiving a zero blood ADH signal, the kidneys produce huge unchanging volumes of very dilute urine, causing dehydration and death if not treated.

As organisms age, the efficiency of their control systems becomes reduced. The inefficiencies gradually result in an unstable internal environment that increases the risk of illness, and leads to the physical changes associated with aging.<ref name=Marieb/>

Various [[chronic (medicine)|chronic]] diseases are kept under control by homeostatic compensation, which masks a problem by compensating for it (making up for it) in another way. However, the compensating mechanisms eventually wear out or are disrupted by a new complicating factor (such as the advent of a concurrent acute viral infection), which sends the body reeling through a new cascade of events. Such decompensation unmasks the underlying disease, worsening its symptoms. Common examples include decompensated [[heart failure]], [[kidney failure]], and [[liver failure]].{{citation needed|date=April 2023}}