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Understanding the Changes in Mitochondrial Morphology through Dynamic and Three-dimensional Fluorescence Micrographs
Published on: August 15, 2025
TZDs reduce mitochondrial ROS production and enhance mitochondrial biogenesis
Kazuo Fujisawa1, Takeshi Nishikawa, Daisuke Kukidome
1Department of Metabolic Medicine, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan.
Biochemical and Biophysical Research Communications
|December 17, 2008
Summary
Thiazolidinediones (TZDs) like pioglitazone reduce mitochondrial reactive oxygen species (mtROS) in diabetes by activating the PGC-1alpha pathway. This mechanism may prevent diabetic vascular complications.
Area of Science:
- Biochemistry
- Cell Biology
- Endocrinology
Background:
- Hyperglycemia contributes to diabetic complications via mitochondrial reactive oxygen species (mtROS).
- Metformin was previously shown to normalize mtROS by activating the PGC-1alpha pathway.
- The precise mechanism by which thiazolidinediones (TZDs) affect cardiovascular events in type 2 diabetes remains unclear.
Purpose of the Study:
- To investigate whether TZDs can inhibit hyperglycemia-induced mtROS production.
- To determine if TZDs activate the PGC-1alpha pathway, similar to metformin.
- To explore the potential of TZDs in preventing diabetic vascular complications.
Main Methods:
- Treatment of human umbilical vein endothelial cells (HUVECs) with pioglitazone and ciglitazone under hyperglycemic conditions.
- Measurement of reactive oxygen species (ROS) production.
- Assessment of gene expression for NRF-1, TFAM, and MnSOD mRNA.
- Quantification of mitochondrial DNA (mtDNA) and mitochondrial density.
Main Results:
- Pioglitazone and ciglitazone attenuated hyperglycemia-induced ROS production in HUVECs.
- Both TZDs increased the expression of NRF-1, TFAM, and MnSOD mRNA.
- Pioglitazone treatment led to increased mtDNA and mitochondrial density.
Conclusions:
- TZDs, including pioglitazone and ciglitazone, normalize hyperglycemia-induced mtROS production.
- This normalization is achieved by inducing MnSOD and promoting mitochondrial biogenesis through PGC-1alpha activation.
- These findings suggest a mechanism by which TZDs may contribute to the prevention of diabetic vascular complications.
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