Related Experiment Video
Updated: Jul 1, 2025
08:32
Studying the Hypothalamic Insulin Signal to Peripheral Glucose Intolerance with a Continuous Drug Infusion System into the Mouse Brain
Published on: January 4, 2018
10.3K
Effects of Alterations in Acid-Base Effects on Insulin Signaling
Lynda A Frassetto1, Umesh Masharani2
1Department of Medicine, Division of Nephrology, University of California San Francisco, San Francisco, CA 94143, USA.
International Journal of Molecular Sciences
|March 13, 2024
Summary
Mildly increased body acidity, or "acid stress," may impair insulin action. This condition, linked to diet and aging, affects glucose regulation in tissues like muscle and liver.
Area of Science:
- Endocrinology and Metabolism
- Physiology
- Renal Physiology
Background:
- Insulin is crucial for glucose homeostasis, regulating blood sugar via muscle, adipose tissue, and liver.
- Acid-base balance is tightly controlled, with metabolic acidosis defined by pH < 7.35 and bicarbonate < 22 mmol/L.
- Western diets and aging can lead to increased body acidity, termed 'acid stress,' potentially impacting health.
Purpose of the Study:
- To explore the effects of acid stress on insulin signaling pathways.
- To investigate how acid stress influences insulin action in key metabolic tissues.
Main Methods:
- Review of existing literature on insulin signaling and acid-base balance.
- Discussion of the physiological impact of chronic, low-grade acidosis.
Main Results:
- Acid stress may interfere with insulin receptor activation and downstream signaling.
- Impaired insulin action due to acid stress could affect glucose uptake in muscle and adipose tissue.
- Hepatic insulin sensitivity may also be modulated by changes in acid-base status.
Conclusions:
- Acid stress represents a potential, underappreciated factor affecting glucose metabolism.
- Further research is warranted to elucidate the precise mechanisms and clinical implications of acid stress on insulin sensitivity.
Related Concept Videos
01:28Insulin: The Receptor and Signaling Pathways
1.2K
Insulin action is mediated through a receptor tyrosine kinase, akin to the IGF-1 receptor. The number of receptors per cell varies significantly, from 40 on erythrocytes to 300,000 on adipocytes and hepatocytes. The insulin receptor consists of linked α/β subunit dimers, forming a heterotetramer glycoprotein with two extracellular α subunits and two β subunits spanning the membrane. The α subunits inhibit the inherent tyrosine kinase activity of the β subunits, but...
1.2K
01:27Glucose Homeostasis: Pancreatic Islets and Insulin Secretion
1.2K
The pancreatic islets comprising only 1%-2% of the volume are highly vascularized and innervated mini-organs. They contain five endocrine cell types, including β cells that secrete insulin, which is synthesized as a single polypeptide chain, preproinsulin, processed to proinsulin, and finally to insulin and C-peptide. This process is complex and regulated, involving the Golgi complex, the endoplasmic reticulum, and the secretory granules of the β cell.
Insulin and C-peptide are...
Insulin and C-peptide are...
1.2K
01:16Hormones Regulating Blood Glucose
3.3K
Insulin is released by beta cells of the pancreas when blood glucose levels are high. It facilitates glucose absorption and utilization in insulin-dependent cells with insulin receptors on their plasma membranes. Insulin promotes glucose uptake by increasing the number of glucose transport proteins in the cell membrane, allowing glucose to enter the cell. As a result, glucose utilization and ATP production are enhanced.
In addition to accelerating glucose uptake and utilization, insulin has...
In addition to accelerating glucose uptake and utilization, insulin has...
3.3K
01:16Insulin: Dosing Regimen and Adverse Effects
170
Insulin-replacement therapy usually includes both long-acting insulin (basal) and short-acting insulin (to cater to postprandial needs). In a diverse group of type 1 diabetes patients, the average daily insulin dose is typically 0.5-0.7 units/kg body weight. However, obese patients and pubertal adolescents may need more due to insulin resistance.
The basal dose constitutes about 40%-50% of the total daily dose, with the rest as premeal insulin. The mealtime insulin dose should mirror...
The basal dose constitutes about 40%-50% of the total daily dose, with the rest as premeal insulin. The mealtime insulin dose should mirror...
170
01:25Insulin: Biosynthesis, Chemistry, and Preparation
374
The endoplasmic reticulum (ER) of pancreatic β-cells synthesizes preproinsulin, which consists of a signal peptide, A and B chains, and a C-peptide. Preproinsulin is then cleaved and folded into proinsulin, which translocates to the Golgi apparatus for sorting and packaging into secretory granules. In these granules, enzymatic clipping generates insulin and C-peptide.
Damage or functional impairment of β-cells inhibits insulin production, leading to diabetes. Diabetes treatment...
Damage or functional impairment of β-cells inhibits insulin production, leading to diabetes. Diabetes treatment...
374
01:05Insulin Secretory Vesicles
5.0K
Insulin secretory vesicles release insulin to stimulate blood glucose uptake and regulate carbohydrate metabolism. When the blood glucose levels increase, glucose enters the pancreatic β-islet cells through glucose transporters. Once inside, glucose is metabolized through glycolysis, the citric acid cycle, and the electron transport chain, producing ATP. This increase in ATP concentration closes ATP-sensitive potassium channels, leading to depolarization of the membrane and the opening of...
5.0K