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Updated: Oct 11, 2025
Modeling and Evaluation of Murine Diabetic Cardiomyopathy Model
Published on: November 29, 2024
Comparative study on molecular mechanism of diabetic myopathy in two different types of streptozotocin-induced
Tolulope Peter Saliu1, Thanutchaporn Kumrungsee1, Kenshu Miyata1
1Graduate School of Integrated Sciences for Life, Hiroshima University, 4-4 Kagamiyama 1-chome, Higashi-Hiroshima 739-8528, Japan.
Aims:
Streptozotocin (STZ)-induced diabetic animal models have been widely used to study diabetic myopathy; however, non-specific cytotoxic effects of high-dose STZ have been discussed. The purpose of this study was to compare diabetic myopathy in a high-STZ model with another well-established STZ model with reduced cytotoxicity (high-fat diet (HFD) and low-dose STZ) and to identify mechanistic insights underlying diabetic myopathy in STZ models that can mimic perturbations observed in human patients with diabetic myopathy.
Main Methods:
Male C57BL6 mice were injected with a single high dose of STZ (180 mg/kg, High-STZ) or were given HFD plus low-dose STZ injection (STZ, 55 mg/kg/day, five consecutive days, HFD/STZ). We characterized diabetic myopathy by histological and immunochemical analyses and conducted gene expression analysis.
Key Findings:
The high-STZ model showed a significant reduction in tibialis anterior myofiber size along with decreased satellite cell content and downregulation of inflammation response and collagen gene expression. Interestingly, blood corticosteroid levels were significantly increased in the high-STZ model, which was possibly related to lowered inflammation response-related gene expression. Further analyses using the HFD/STZ model showed downregulation of gene expression related to mitochondrial functions accompanied by a significant decrease in ATP levels in the muscles.
Significance:
The high-STZ model is suitable for studies regarding not only severe diabetic myopathy with excessive blood glucose but also negative impact of glucocorticoids on skeletal muscles. In contrast, the HFD/STZ model is characterized by higher immune responses and lower ATP production, which also reflects the pathologies observed in human diabetic patients.
Insights
This study compared two models of diabetic myopathy. The high-dose streptozotocin (STZ) model showed reduced inflammation and increased corticosteroids, while the high-fat diet/low-dose STZ model revealed mitochondrial dysfunction and lower ATP levels in muscles.
Area of Science:
- * Endocrinology and Metabolism
- * Skeletal Muscle Physiology
- * Diabetic Complications
Background:
- * Streptozotocin (STZ)-induced diabetic animal models are crucial for studying diabetic myopathy.
- * Concerns exist regarding the non-specific cytotoxic effects of high-dose STZ.
- * Alternative models with reduced cytotoxicity are needed to better mimic human diabetic myopathy.
Purpose of the Study:
- * To compare diabetic myopathy induced by high-dose STZ versus a high-fat diet (HFD) combined with low-dose STZ.
- * To identify mechanistic insights into diabetic myopathy in STZ models relevant to human patients.
- * To evaluate the suitability of different STZ models for specific research questions.
Main Methods:
- * Male C57BL6 mice were used in two experimental groups: High-STZ (single high dose, 180 mg/kg) and HFD/STZ (HFD plus five daily low doses of STZ, 55 mg/kg/day).
- * Diabetic myopathy was assessed using histological and immunochemical analyses.
- * Gene expression analysis was performed to investigate molecular changes.
Main Results:
- * The High-STZ model exhibited reduced tibialis anterior myofiber size, decreased satellite cell content, and downregulated inflammation and collagen gene expression.
- * Elevated blood corticosteroid levels were observed in the High-STZ model, potentially linked to reduced inflammation gene expression.
- * The HFD/STZ model demonstrated downregulated mitochondrial function gene expression and significantly decreased muscle ATP levels.
Conclusions:
- * The High-STZ model is appropriate for studying severe diabetic myopathy and the impact of glucocorticoids on skeletal muscle.
- * The HFD/STZ model effectively reflects human diabetic myopathy pathologies, characterized by increased immune responses and impaired mitochondrial ATP production.
- * Both models offer distinct advantages for investigating different facets of diabetic myopathy.
