阿德莱德大学的研究人员发现了一种高脂饮食可能削弱在胃中能产生饱腹感的重要接收器。
发表在《PLOS ONE》杂志上的一篇文章显示，南澳大利亚卫生和医学研究所营养和胃肠疾病中心的研究人员，在实验室研究胃中的热辣椒感受器(TRPV1)与饱腹感之间的关系。
“当胃中充满食物时胃开始伸长，食物刺激胃中神经告诉身体已胃经满了，我们发现这种激活过程是通过热辣椒或热辣椒感受器来调节的。”高级研究员副教授Amanda Page说。
以前的研究发现热辣椒中的辣椒素可减少食物的摄入量。我们发现的热辣椒感受器的减少可抑制胃伸缩神经的反应，导致饱腹感觉的延迟并消耗更多的食物。因此部分辣椒素对食物摄入量的影响可能是通过胃来介导的。
“我们还发现，TRPV1感受器可以阻止引起肥胖的高脂肪饮食。”Amanda Page说。Stephen Kentish博士说，这些发现将进行更进一步的研究并发展新疗法。
“这是令人兴奋的，我们现在知道更多的关于TRPV1感受器通路，食用辣椒素可以通过胃中刺激神经防止暴饮暴食，”Kentish博士说。
“下一阶段的研究将包括调查TRPV1感受器激活的机制，目的是研究更好的治疗方法。
“我们还将做进一步的工作来确定为什么高脂肪饮食可降低TRPV1感受器的敏感性并研究我们是否能逆转这样的损害。”他说。
doi:10.1371/journal.pone.0135892
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TRPV1 Channels and Gastric Vagal Afferent Signalling in Lean and High Fat Diet Induced Obese Mice
Stephen J. Kentish, Claudine L. Frisby, Stamatiki Kritas, Hui Li, George Hatzinikolas, Tracey A. O’Donnell, Gary A. Wittert, Amanda J. Page
Abstract Within the gastrointestinal tract vagal afferents play a role in control of food intake and satiety signalling. Activation of mechanosensitive gastric vagal afferents induces satiety. However, gastric vagal afferent responses to mechanical stretch are reduced in high fat diet mice. Transient receptor potential vanilloid 1 channels (TRPV1) are expressed in vagal afferents and knockout of TRPV1 reduces gastro-oesophageal vagal afferent responses to stretch. We aimed to determine the role of TRPV1 on gastric vagal afferent mechanosensitivity and food intake in lean and HFD-induced obese mice. Methods TRPV1+/+ and -/- mice were fed either a standard laboratory diet or high fat diet for 20wks. Gastric emptying of a solid meal and gastric vagal afferent mechanosensitivity was determined. Results Gastric emptying was delayed in high fat diet mice but there was no difference between TRPV1+/+ and -/- mice on either diet. TRPV1 mRNA expression in whole nodose ganglia of TRPV1+/+ mice was similar in both dietary groups. The TRPV1 agonist N-oleoyldopamine potentiated the response of tension receptors in standard laboratory diet but not high fat diet mice. Food intake was greater in the standard laboratory diet TRPV1-/- compared to TRPV1+/+ mice. This was associated with reduced response of tension receptors to stretch in standard laboratory diet TRPV1-/- mice. Tension receptor responses to stretch were decreased in high fat diet compared to standard laboratory diet TRPV1+/+ mice; an effect not observed in TRPV1-/- mice. Disruption of TRPV1 had no effect on the response of mucosal receptors to mucosal stroking in mice on either diet. Conclusion TRPV1 channels selectively modulate gastric vagal afferent tension receptor mechanosensitivity and may mediate the reduction in gastric vagal afferent mechanosensitivity in high fat diet-induced obesity.