Atrophy

. Atrophy refers to the decrease of formerly normal body structures such as organoids, cells, and organs. This occurs as they adapt to physiological and pathological conditions. Atrophy can involve the entire body. It can be physiological and pathological, general and local. Physiological atrophy, or involution, is the physiological cessation or weakening of function (reduction of organs and structures), as well as atrophy of hormone-dependent tissues (e.g., uterine walls, breasts after childbirth, etc.). It occurs through apoptosis. Pathological atrophy can be general and local. The cause of general atrophy can be inadequate or unbalanced nutrition, impaired nutrient absorption due to severe illnesses (malignant tumors, gastrointestinal diseases, chronic infections, e.g., tuberculosis). The condition when the atrophy of the body reaches the highest phase (loses 40-50% of mass) is called cachexia. Cachexia is the wasting away of patients with malignant tumors. Initially, adipose tissue disappears, later the skeletal muscles, bones, internal organs (liver, spleen, heart, thyroid) atrophy. All these processes are adaptive, aiming to maintain vital organs such as the central nervous system, kidneys, and circulating blood as long as possible. Local (partial) atrophy can start due to gradually decreasing blood supply to the body, disrupted innervation, altered hormonal regulation, etc.

Source | Glossary of Most Commonly Used Biomedical Terms and Concepts | Lithuanian University of Health Sciences | Academician Professor Antanas Praškevičius, Professor Laima Ivanovienė