Circulating Follistatin Is Liver-Derived and Regulated by the Glucagon-to-Insulin Ratio

Jakob S Hansen1, Sabine Rutti1, Caroline Arous1

  • 1The Centre of Inflammation and Metabolism and the Centre for Physical Activity Research (J.S.H., B.K.P., P.P.), Rigshospitalet, University of Copenhagen, Denmark 2100; Department of Clinical Biochemistry (J.S.H., P.P.), Rigshospitalet, Copenhagen, Denmark 2100; Department of Genetic Medicine and Development (S.R., C.A., P.A.H., K.B.), University Medical Centre, University of Geneva, Geneva, Switzerland 1206; Department of Hepatology (J.O.C.), Rigshospitalet, Copenhagen, Denmark 2100; Department of Anaesthesiology (N.H.S.), The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen, Denmark 2100; Division of Pathobiochemistry and Clinical Chemistry (A.D., C.W.), Department of Internal Medicine IV, University Tuebingen, Germany 72076; University Hospitals of Geneva (C.G.-G.), Surgical Research Unit, Geneva, Switzerland 1206; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München (C.W.), University of Tuebingen, Tuebingen, Germany 72076; German Center for Diabetes Research (C.W.), München-Neuherberg, Germany 85764.

Abstract

Related Concept Videos

Hormones Regulating Blood Glucose01:16

Hormones Regulating Blood Glucose

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...
8.4K
Glucose Homeostasis: Regulation of Blood Glucose01:02

Glucose Homeostasis: Regulation of Blood Glucose

Carbohydrates consumed through foods are converted into glucose, a crucial energy source for the body. In the prandial state, high blood glucose levels stimulate the secretion of insulin from the pancreas. Insulin inhibits hepatic glucose production and stimulates glucose uptake and metabolism by muscle and adipose tissue. The excess glucose is converted into glycogen and stored in the liver and muscles.
During fasting, when blood glucose levels are low, the pancreas secretes glucagon. it...
5.3K
Glucose Homeostasis: Pancreatic Islets and Insulin Secretion01:27

Glucose Homeostasis: Pancreatic Islets and Insulin Secretion

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...
3.1K
Insulin: The Receptor and Signaling Pathways01:28

Insulin: The Receptor and Signaling Pathways

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...
6.0K
Feedback Loops01:01

Feedback Loops

In most cases, excessive hormone production is prevented by negative feedback—a loop that starts with a stimulus inducing the release of a particular substance, like a hormone, to maintain a certain level before triggering a signal that results in a decrease in further release of the hormone.
67.7K
Liver Physiology01:30

Liver Physiology

The liver, an essential organ in the human body, performs over 200 vital functions that can be broadly categorized into metabolic, hematological, endocrine regulation, and bile production.
Metabolic Regulation:
The liver is the central organ involved in regulating blood composition. It stabilizes blood glucose levels, maintaining them within the range of  70–110 mg/dL. When these levels drop, the liver breaks down glycogen reserves and releases glucose into the bloodstream. It can...
4.2K