Department of Biological Sciences, University at Buffalo, The State University of New York, Buffalo, New York, United States of America.
PLoS One. 2013 Nov 13;8(11):e79403. doi: 10.1371/journal.pone.0079403. eCollection 2013.
Obesity is a growing epidemic that causes many serious health related complications. While the causes of obesity are complex, there is conclusive evidence that overconsumption coupled with a sedentary lifestyle is the primary cause of this medical condition. Dietary consumption is controlled by appetite which is in turn regulated by multiple neuronal systems, including the taste system. However, the relationship between taste and obesity has not been well defined. Growing evidence suggests that taste perception in the brain is altered in obese animals and humans, however no studies have determined if there are altered taste responses in the peripheral taste receptor cells, which is the initiation site for the detection and perception of taste stimuli.
METHODOLOGY/PRINCIPAL FINDINGS: In this study, we used C57Bl/6 mice which readily become obese when placed on a high fat diet. After ten weeks on the high fat diet, we used calcium imaging to measure how taste-evoked calcium signals were affected in the obese mice. We found that significantly fewer taste receptor cells were responsive to some appetitive taste stimuli while the numbers of taste cells that were sensitive to aversive taste stimuli did not change. Properties of the taste-evoked calcium signals were also significantly altered in the obese mice. Behavioral analyses found that mice on the high fat diet had reduced ability to detect some taste stimuli compared to their littermate controls.
CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate that diet-induced obesity significantly influences peripheral taste receptor cell signals which likely leads to changes in the central taste system and may cause altered taste perception.
肥胖是一种日益严重的流行病，会导致许多严重的健康相关并发症。虽然肥胖的原因很复杂，但有确凿的证据表明，过度摄入食物加上久坐的生活方式是导致这种疾病的主要原因。饮食摄入受食欲控制，而食欲反过来又受到多个神经元系统的调节，包括味觉系统。然而，味觉与肥胖之间的关系尚未得到明确界定。越来越多的证据表明，肥胖动物和人类的大脑味觉感知发生了改变，但是没有研究确定外周味觉受体细胞是否存在味觉反应的改变，外周味觉受体细胞是味觉刺激的检测和感知的起始部位。
方法/主要发现：在这项研究中，我们使用了 C57Bl/6 小鼠，当它们被置于高脂肪饮食中时，它们很容易肥胖。在高脂肪饮食 10 周后，我们使用钙成像来测量肥胖小鼠的味觉诱发钙信号受到了怎样的影响。我们发现，与对照组相比，肥胖小鼠中响应某些食欲性味觉刺激的味觉受体细胞数量明显减少，而对厌恶性味觉刺激敏感的味觉细胞数量没有变化。肥胖小鼠的味觉诱发钙信号特性也发生了显著改变。行为分析发现，高脂肪饮食组的小鼠对某些味觉刺激的检测能力下降。
结论/意义：我们的研究结果表明，饮食诱导的肥胖显著影响外周味觉受体细胞信号，这可能导致中枢味觉系统的变化，并可能导致味觉感知的改变。
