China
Africa
Explore chapters and articles related to this topic
Macronutrients
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Adrenocortical hormones are produced by the adrenal cortex of suprarenal glands and consist of glucocorticoids and mineralocorticoids. Glucocorticoid is a steroid hormone produced by the suprarenal or adrenal gland and known particularly for its anti-inflammatory and immunosuppressive actions. Cortisol is the principal glucocorticoid in many species, including humans. Mineralocorticoids stimulate the retention of sodium in the extracellular body fluids. The most potent mineralocorticoid of all species is aldosterone.
Endocrine diseases and pregnancy
Published in Hung N. Winn, Frank A. Chervenak, Roberto Romero, Clinical Maternal-Fetal Medicine Online, 2021
The other major adrenal cortical steroid hormone, aldosterone, is a mineralocorticoid promoting renal sodium reabsorption and potassium excretion, and maintenance of extracellular fluid volume and blood pressure. Although ACTH stimulates aldosterone secretion, the primary regulation of aldosterone secretion is via the renin–angiotensin signal pathway. Decreased delivery of sodium to glomeruli via afferent arterioles in the nephron stimulates renin secretion by juxtaglomerular cells. Renin in turn activates the angiotensin-converting enzyme, resulting to conversion of inactive angiotensin-1 to active angiotensin-2 in the lung; angiotensin-2 is the major stimulant of aldosterone synthesis and secretion by the adrenal. Aldosterone in turn promotes renal sodium conservation and extracellular fluid volume expansion, resulting in rising arterial pressure and increasing delivery of water and sodium to the proximal nephron. Renin secretion is inhibited by increased sodium delivery to the afferent renal arteriole, thereby completing the feedback loop of the renin–angiotensin–aldosterone axis.
Adrenocortical Disease
Published in T.M. Craft, P.M. Upton, Key Topics In Anaesthesia, 2021
The adrenal cortex produces glucocorticoid, mineralocorticoid and sex hormones (mainly testosterone). Cortisol, the principal glucocorticoid, modulates stress and inflammatory responses. It is a potent stimulator of gluconeogenesis and antagonizes insulin. Aldosterone is the principal mineralocorticoid. It causes increased sodium reabsorption, and potassium and hydrogen ion loss at the distal renal tubule. Adrenal androgen production increases markedly at puberty, declining with age thereafter. Androstenedione is converted by the liver to testosterone in the male and oestrogen in the female. Cortisol and androgen production are under diurnal pituitary control (adrenocorticotrophic hormone — ACTH). Aldosterone is released in response to angiotensin II, produced following renal renin release and subsequent pulmonary angiotensin I conversion.
A novel homozygous CYP17A1 mutation causes partial 17 α-hydroxylase/17,20-lyase deficiency in 46,XX: a case report and literature review
Published in Blood Pressure, 2023
Heye Chen, Yingting Chen, Hongxian Mao, Huaying Huang, Xueyong Lou
17 α-Hydroxylase/17,20-lyase deficiency (17-OHD) is an extremely rare autosomal recessive disorder caused by mutations in the CYP17A1 gene, which encodes the P450c17 enzyme. This enzyme plays a critical role in the production of both glucocorticoids and sex steroids, specifically by regulating the activities of 17 α-hydroxylase and 17,20-lyase, respectively [1,2]. The deficiency of 17 α-hydroxylase and 17,20-lyase has a significant impact on the patient’s health. The 17-hydroxylase deficiency results in decreased cortisol levels, which compensatively stimulates the secretion of adrenocorticotropic hormone (ACTH). It also increases the production of mineralocorticoid precursors, corticosterone, and 11-deoxycorticosterone (DOC), ultimately resulting in hypertension and hypokalaemia. In contrast, the 17,20-lyase deficiency leads to decreased sex steroid production, which compensatively stimulates Follicle-Stimulating Hormone (FSH) and luteinizing hormone (LH), resulting in primary amenorrhoea and a lack of secondary sex characteristics [3]. Overall, patients with 17-OHD typically present with hypertension, hypokalaemia, primary amenorrhoea, and a lack of secondary sex characteristics.
A patent review of aldosterone synthase inhibitors (2014-present)
Published in Expert Opinion on Therapeutic Patents, 2022
As a key component of the renin-angiotensin-aldosterone system (RAAS), mineralocorticoid aldosterone has been well recognized for its principal role in regulating fluid and electrolyte balance [1]. It promotes renal sodium (Na+) and water reabsorption, and induces potassium (K+) and hydrogen (H+) excretion in epithelial cells of the distal nephron [2]. Not surprisingly, dysregulation of aldosterone, either excess or deficiency, has been linked to the clinical conditions of various cardiovascular and metabolic diseases. ‘Hyperaldosteronism’ (excess aldosterone) contributes to arterial hypertension (AH), congestive heart failure, and chronic kidney disease (CKD) [3,4]. Meanwhile, aldosterone deficiency or ‘hypoaldosteronism’ results in hyponatremia, hyperkalemia, and acidosis [5,6].
‘Drink clean, safe water and/or other fluids through-out the day even if you do not feel thirsty’: a food-based dietary guideline for the elderly in South Africa
Published in South African Journal of Clinical Nutrition, 2021
Upasana Mukherjee, Carin Napier, Wilna Oldewage-Theron
The most important hormones in the maintenance of body fluid levels are part of the renin-angiotensin system. In response to extracellular fluid loss, rennin is secreted and it increases water uptake and retention by the kidneys. Renin also stimulates the secretion of angiotensin, which induces thirst sensations through the hypothalamus of the brain. With the progression of age, the rennin function is lowered and the kidneys lose the ability to concentrate urine. Angiotensin stimulation of thirst may also be impaired as studies on rats reported that adding angiotensin stimulants in drinks does not increase thirst in the elderly as it would normally do in younger animals.13,27 The second important set of hormones regulating water balance are part of the arginine vasopressin system. Vasopressin is called the antidiuretic hormone because of its potent ability to increase fluid retention in the kidneys. Aldosterone is a mineralocorticoid that primarily regulates sodium balance in the kidneys by stimulating sodium reabsorption and potassium excretion. Both secretion and sensitivity of the hormone is reduced due to ageing.13,27,52