Related Experiment Video
Updated: Dec 17, 2025
12:32
High-resolution Respirometry to Measure Mitochondrial Function of Intact Beta Cells in the Presence of Natural Compounds
Published on: January 23, 2018
12.8K
Rice Bran Phenolic Extracts Modulate Insulin Secretion and Gene Expression Associated with β-Cell Function
Nancy Saji1,2, Nidhish Francis1,3, Lachlan J Schwarz1,4
1Australian Research Council (ARC) Industrial Transformation Training Centre (ITTC) for Functional Grains, Graham Centre for Agricultural Innovation, Charles Sturt University, Wagga Wagga, NSW 2650, Australia.
Nutrients
|July 1, 2020
Summary
Rice bran phenolic extracts enhance beta-cell function by increasing key gene expression and insulin secretion. This suggests a potential therapeutic role for rice bran in managing type 2 diabetes mellitus.
Area of Science:
- Metabolic pathways
- Nutritional biochemistry
- Molecular endocrinology
Background:
- Oxidative stress impairs beta-cell function and contributes to type 2 diabetes mellitus (T2DM).
- Rice bran (RB) phenolic extracts possess bioactive properties potentially beneficial for metabolic health.
Purpose of the Study:
- To investigate the effects of stabilized RB phenolic extracts on genes crucial for beta-cell function.
- To evaluate the impact of RB phenolic extracts on glucose-stimulated insulin secretion.
Main Methods:
- Treatment of cells with varying concentrations of RB phenolic extracts (25-250 µg/mL).
- Assessment of gene expression for glucose transporter 2 (Glut2), pancreatic and duodenal homeobox 1 (Pdx1), sirtuin 1 (Sirt1), mitochondrial transcription factor A (Tfam), and insulin 1 (Ins1).
- Measurement of glucose-stimulated insulin secretion under normal and high glucose conditions.
Main Results:
- RB phenolic extracts significantly upregulated the expression of Glut2, Pdx1, Sirt1, Tfam, and Ins1 genes.
- Enhanced glucose-stimulated insulin secretion was observed in response to RB phenolic extract treatment.
- These effects were consistent under both normal and high glucose conditions.
Conclusions:
- Stabilized RB phenolic extracts favorably modulate genes involved in beta-cell function and insulin secretion.
- Potential mechanisms include polyphenol synergy, antioxidant activity, and stimulation of insulin secretion effectors.
- RB phenolic extracts show promise in addressing beta-cell dysfunction associated with T2DM.
Related Concept Videos
01:58Cell Specific Gene Expression
16.1K
Multicellular organisms contain a variety of structurally and functionally distinct cell types, but the DNA in all the cells originated from the same parent cells. The differences in the cells can be attributed to the differential gene expression. Liver cells, whose functions include detoxification of blood, production of bile to metabolize fats, and synthesis of proteins essential for metabolism, must express a specific set of genes to perform their functions. Gene expression also varies with...
16.1K
01:16Hormones Regulating Blood Glucose
6.0K
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...
6.0K
01:28Insulin: The Receptor and Signaling Pathways
2.3K
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...
2.3K
01:05Insulin 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
01:27Glucose Homeostasis: Pancreatic Islets and Insulin Secretion
1.9K
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...
1.9K
01:25Insulin: Biosynthesis, Chemistry, and Preparation
1.0K
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...
1.0K