FGF19は,食後のインスリン独立活性化剤として,肝臓のタンパク質とグリコゲン合成を活性化します
関連する実験動画
Serkan Kir1, Sara A Beddow, Varman T Samuel
1Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA.
まとめ
フィブロブラスト成長因子 (FGF) 19はエンテロカインであり,インスリンとは独立して肝臓のタンパク質とグリコゲン合成を刺激する. この発見は,マウスの代謝を調節する重要な内分泌経路を明らかにしています.
科学分野:
- エンドクリノロジー エンドクリノロジー
- メタボリック・レギュレーション
- 肝臓病理学 肝臓病理学
背景:
- フィブロブラスト成長因子 (FGF) 19は,胆汁酸に反応してイレウムから放出されるエンテロカインです.
- 肝臓の代謝,特にインスリンシグナル伝達におけるその役割については,さらなる解明が必要である.
研究 の 目的:
- 肝臓のタンパク質とグリコゲン合成に対するFGF19の代謝効果を調査する.
- FGF19の行動を媒介するシグナル伝達経路を特定し,インスリンとAktの独立性に焦点を当てた.
- マウスモデルを使用して,グルコースとグリコゲンの恒常性におけるFGF19の生理学的重要性を評価する.
主な方法:
- 肝臓タンパク質とグリコゲン合成に対するFGF19の影響を評価するインビトロおよびインビボ実験.
- ミトゲン活性化タンパク質キナーゼ (MAPK) とAkt.を含むシグナル伝達経路の分析.
- FGF15欠乏したマウス (FGF19のオートログ) を用いて,グルコースとグリコゲンの代謝を研究した.
- 糖尿病のマウスモデルにおけるFGF19の効果を調査する.
主要な成果:
- FGF19は,リポゲネシスを誘導することなく,肝臓のタンパク質とグリコゲン合成を著しく刺激します.
- FGF19の効果はインスリンとAktのシグナル伝達とは独立しており,MAPK経路によって媒介される.
- FGF15欠乏したマウスは,グルコースホメオスタシスの障害と肝臓のグリコゲンの減少を示した.
- FGF19治療は,インスリン不足の糖尿病マウスの肝臓のグリコゲンレベルを正常化させた.
結論:
- FGF19は,肝臓のタンパク質とグリコゲンの代謝に不可欠なインスリンに依存しない内分泌経路を活性化させます.
- この経路は,MAPKのシグナル伝達を含み,タンパク質翻訳機構とグリコゲン合成酵素に影響を与えます.
- FGF19は,グルコースとグリコゲンのホメオスタシスを維持する上で重要な役割を果たし,潜在的な治療的洞察を提供します.
関連する概念動画
Glucagon-like Receptor Agonists
798
Incretins include glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), which stimulate insulin secretion post-meals. In type 2 diabetes, GIP's efficacy is reduced, making GLP-1 a viable drug target. GIP originates from preproGIP.
GLP-1, when administered in high doses intravenously, triggers insulin secretion, inhibits glucagon release, slows gastric emptying, reduces food intake, and restores normal insulin secretion. However, its rapid inactivation by...
GLP-1, when administered in high doses intravenously, triggers insulin secretion, inhibits glucagon release, slows gastric emptying, reduces food intake, and restores normal insulin secretion. However, its rapid inactivation by...
798
Hormones Regulating Blood Glucose
6.3K
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...
6.3K
Insulin Secretory Vesicles
6.3K
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...
6.3K
Glucose Homeostasis: Pancreatic Islets and Insulin Secretion
2.1K
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...
2.1K
Insulin: The Receptor and Signaling Pathways
2.6K
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...
2.6K
Dipeptidyl Peptidase 4 Inhibitors
537
Dipeptidyl peptidase 4 (DPP-4) is a serine protease widely distributed in the body. It's involved in the inactivation of GLP-1 and GIP hormones, which are crucial for insulin regulation. DPP-4 inhibitors, such as sitagliptin (Januvia), saxagliptin (Onglyza), linagliptin (Tradjenta), alogliptin (Nesina), and vildagliptin (Galvus), help increase the proportion of active GLP-1, enhancing insulin secretion. These inhibitors work by competitively binding to DPP-4. This binding causes a...
537