Molecular Physiology Laboratory, Department of Biochemistry, Bharathiar University, Marudhamalai Road, Coimbatore, Tamil Nadu, 641046, India.
Molecular Biology Laboratory, Department of Botany, Bharathiar University, Marudhamalai Road, Coimbatore, Tamil Nadu, 641046, India.
Acta Physiol (Oxf). 2023 Aug;238(4):e13968. doi: 10.1111/apha.13968. Epub 2023 Apr 3.
Obesity is a major public health issue, which is associated with several chronic diseases. In rodents, voluntary wheel running (VWR) is a type of exercise that influences ingestive behavior. This study aims to investigate the possible function of VWR activity in the perception of fat taste and if it mitigates the immediate effects of fatty acid (FA) ingestion.
Male C57BL/6 mice were arbitrarily assigned to either a sedentary (SED) lifestyle or free access to a running wheel after 5 weeks of dietary regimen. Later these mice groups were used in the investigations on fat preference, metabolic tolerance, and electrophysiology. Diet-induced alterations in CD36 and GPR120 expression that are related to fat perception and the capacitative calcium signaling caused by FA in taste bud cells (TBCs) were also examined.
In obese groups, VWR temporarily reduced body weight, demonstrated improvement in preference scores for FA, and recovered from a deterioration in glucose homeostasis. In CD36-positive TBCs, electrophysiological investigations showed alterations in [Ca ]i caused by FA. Further, in the TBCs of circumvallate papillae, there are differences in the expression of the genes CD36 and GPR120 between the active and SED controls. Obese mice also show lower incentive salience for long-chain fatty acids (LCFA) and adapted to the reward system of VWR which may lead to improved incentive salience accredited to wheel running.
In conclusion, this study provides the first evidence that VWR causes orosensory adaptations to fat and appears to alter taste preference for LCFAs.
肥胖是一个主要的公共卫生问题，它与几种慢性疾病有关。在啮齿动物中，自愿轮跑（VWR）是一种影响摄食行为的运动。本研究旨在探讨 VWR 活动在感知脂肪味道中的可能作用，以及它是否减轻脂肪酸（FA）摄入的即时影响。
雄性 C57BL/6 小鼠在 5 周的饮食方案后，被任意分配到久坐（SED）生活方式或自由使用跑步轮。之后，这些小鼠被用于脂肪偏好、代谢耐受性和电生理学的研究。还检查了与脂肪感知有关的 CD36 和 GPR120 表达的饮食诱导改变，以及 FA 在味蕾细胞（TBC）中引起的电容钙信号。
在肥胖组中，VWR 暂时减轻了体重，增加了对 FA 的偏好评分，并从葡萄糖稳态恶化中恢复过来。在 CD36 阳性 TBC 中，电生理学研究显示 FA 引起的 [Ca ]i 改变。此外，在环状乳突的 TBC 中，CD36 和 GPR120 基因的表达在活动和 SED 对照组之间存在差异。肥胖小鼠对长链脂肪酸（LCFA）的激励性明显降低，并且适应了 VWR 的奖励系统，这可能导致由于轮跑而改善激励性明显。
总之，本研究首次提供了证据表明 VWR 导致味觉对脂肪的适应性变化，并似乎改变了对 LCFAs 的味觉偏好。
