# Does Green Tea Ameliorate Obesity in Mice Kept at Thermoneutrality by Modulating Skeletal Muscle Metabolism?

## TL;DR

Green tea may help reduce obesity effects in mice by improving muscle metabolism and insulin sensitivity, even in a warm environment.

## Contribution

This study is the first to show green tea's benefits on skeletal muscle metabolism in thermoneutral obese mice.

## Key findings

- Green tea improved muscle fiber size and lipid metabolism gene expression in obese mice.
- It enhanced insulin and glucose sensitivity without affecting fatty acid oxidation.
- Green tea increased glucose uptake and lactate dehydrogenase activity in skeletal muscle.

## Abstract

The effects of green tea on metabolic diseases such as obesity and diabetes have been extensively studied. Obesity often leads to insulin resistance, particularly in peripheral tissues such as skeletal muscle. Green tea has shown promise in mitigating insulin resistance in several diet‐induced obesity models. However, its ability to improve insulin sensitivity by modulating skeletal muscle metabolism in the absence of metabolic stress, such as constant cold exposure, remains unclear. Therefore, the aim of this study was to evaluate the effect of green tea on skeletal muscle metabolism in high‐fat diet (HFD)‐induced obese mice maintained at thermoneutrality (28°C). Male C57BL/6 mice were fed a control diet or an HFD for 4 weeks. Then, the HFD group mice were treated with green tea extract (500 mg/kg of body weight) while maintained at thermoneutrality (28°C). At the end of the experimental protocol, we performed metabolic analyses. This study suggested that green tea treatment attenuates the negative effects of HFD by improving muscle fiber cross‐sectional area in the gastrocnemius muscle and increasing the expression of genes involved in lipid metabolism. Although no effect was observed on fatty acid oxidation, green tea improved insulin and glucose sensitivity, as evidenced by glucose and insulin tolerance tests. It also increased the expression of genes associated with glucose uptake and lactate dehydrogenase activity in skeletal muscle. These findings suggest that green tea treatment improves insulin sensitivity by influencing skeletal muscle metabolism even in obese mice maintained at thermoneutrality.

The study on the effect of green tea on obesity in mice kept at thermoneutrality is significant as it addresses a less‐explored area in metabolism and nutrition research.
Maintaining mice at thermoneutrality is crucial as it eliminates the confounding effects of thermal stress that can bias metabolic responses.By evaluating the influence of green tea on muscle metabolism under these controlled conditions, the study offers important insights into the potential for improving insulin sensitivity and muscle function in obesity.The results suggest that green tea can mitigate the negative effects of a high‐fat diet, making it a potential supplement for dietary interventions.This study not only adds to the existing scientific knowledge but also highlights the necessity of considering thermoneutral environments in future studies.

Maintaining mice at thermoneutrality is crucial as it eliminates the confounding effects of thermal stress that can bias metabolic responses.

By evaluating the influence of green tea on muscle metabolism under these controlled conditions, the study offers important insights into the potential for improving insulin sensitivity and muscle function in obesity.

The results suggest that green tea can mitigate the negative effects of a high‐fat diet, making it a potential supplement for dietary interventions.

This study not only adds to the existing scientific knowledge but also highlights the necessity of considering thermoneutral environments in future studies.