在2型糖尿病人群中恢复PITPNA可以逆转胰腺β细胞功能障碍
Yu-Te Yeh1,2, Chandan Sona1,2, Xin Yan3,4
1Johns Hopkins University, All Children's Hospital, St. Petersburg, FL, 33701, USA.
Nature communications
|July 17, 2023
概括
酸丁氨基转移蛋白α (PITPNA) 的缺陷会损害2型糖尿病中的胰岛素颗粒成熟和β细胞功能. 在人体小岛中恢复PITPNA可以扭转这些缺陷,突出其治疗潜力.
科学领域:
- 内分泌学 在内分泌学.
- 细胞生物学 细胞生物学
- 代谢疾病 代谢疾病
背景情况:
- 胰腺β细胞功能障碍是2型糖尿病 (T2D) 发病的核心.
- 胰岛素处理和颗粒成熟的缺陷是T2D中β细胞衰竭的关键因素.
- 氨酸转移蛋白α (PITPNA) 对于产生PtdIns-4-酸盐至关重要,这对于胰岛素颗粒成熟至关重要.
研究的目的:
- 研究PITPNA在胰腺β细胞功能中的作用及其对2型糖尿病的影响.
- 确定PITPNA耗尽是否有助于在T2D中观察到的β细胞功能障碍.
- 探索PITPNA作为T2D的潜在治疗点.
主要方法:
- 在小鼠β细胞中条件删除Pitpna (Ins-Cre,Pitpna).
- 在人类小岛上抑制PITPNA.
- 评估葡萄糖刺激胰岛素分泌 (GSIS),β细胞质量,胰岛素颗粒成熟,亲胰岛素处理和ER压力标记.
主要成果:
- 在小鼠中条件删除Pitpna导致高血糖,减少GSIS和减少β细胞质量.
- 在人群小岛中,PITPNA沉默损害了胰岛素颗粒的成熟和对接,减少了GSIS,并诱导了ER压力.
- 在人类T2D患者的β细胞中观察到降低的PITPNA水平.
结论:
- 在胰腺β细胞中,PITPNA对于适当的胰岛素颗粒成熟,加工和分泌至关重要.
- 降低PITPNA水平与β细胞功能障碍和2型糖尿病的失败有关.
- 在T2D人类小岛中恢复PITPNA可以逆转β细胞缺陷,从而确定PITPNA是关键的治疗标.
相关概念视频
Carbohydrate Metabolism
11.3K
Carbohydrates are polymers composed of molecules containing atoms of carbon, hydrogen and oxygen. One gram of carbohydrate can provide four kilo-calories of energy, which makes it the most efficient instant energy source.
Starch accounts for approximately 60% of the carbohydrates consumed by humans. Since amylase enzymes cannot function in the stomach's acidic environment, starch can only be digested in the mouth and small intestine. Simple sugars are found naturally in milk and fruits in...
Starch accounts for approximately 60% of the carbohydrates consumed by humans. Since amylase enzymes cannot function in the stomach's acidic environment, starch can only be digested in the mouth and small intestine. Simple sugars are found naturally in milk and fruits in...
11.3K
Glucose Homeostasis: Pancreatic Islets and Insulin Secretion
1.3K
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...
1.3K
Tissue Renewal without Stem Cells
1.7K
After cellular or tissue damage, the resident stem cells present in the human body can locally repair and regenerate the damaged tissue or organ. However, even though some tissues do not have stem cells, they can repair and regenerate with the help of pre-existing cells. For example, beta cells of the pancreas and hepatocytes of the liver can divide to renew and regenerate the tissue. Here, both cell division and cell death are well regulated by homeostasis.
However, failure of such a system...
However, failure of such a system...
1.7K
Insulin: Biosynthesis, Chemistry, and Preparation
435
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...
435


