The role of salivary proteins in taste and feeding

唾液蛋白在味觉和进食中的作用

• 批准号: 9172311
• 负责人: Ann-Marie Torregrossa
• 金额: $ 5.16万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9172311
• 关键词: role; salivary; proteins; taste; feeding

DESCRIPTION (provided by applicant): Variation in bitter taste perception may play a key role in diet selection, which has an uncontestable effect on human health. Although bitter compounds are often associated with toxic substances a large number of nutritionally significant food sources contain bitter phytochemicals (e.g., broccoli [1], spinach [2]) many of which can have beneficial value [1, 3] Understanding how bitter taste is perceived and detected is of great importance to understanding diet selection [4] and increasing the acceptability of pediatric medicines [19]. Under normal feeding and drinking conditions taste compounds must inescapably mix with saliva before reaching their receptor targets but very little work has been done examining how salivary proteins modulate taste stimuli and alter bitter taste perception. Seventy percent of all salivary proteins make up a class of proteins referred to as proline-rich proteins (PRPs). PRP production is induced in rats by dietary exposure to tannic acid, a class of plant compounds that animals, including humans, regularly consume. It has been hypothesized that PRPs alter the acceptability of tannic acid by binding to tannins and thereby reduce the perceived intensity of the tannic acid solution [10, 11]. There is evidence to suggest that these proteins may have a similar relationship with other bitters. They are produced in close proximity to bitter taste receptors [13]. Genes for PRPs and bitter taste receptors are interspersed on the same chromosome [5] and lastly, gene linkage studies have implicated a role for PRPs bitter acceptance in humans and mice [15-18]. Specific Aim 1 will establish if long term exposure to bitter compounds can increase the expression of PRPs and establish whether oral exposure is necessary and sufficient to cause induction. Saliva will be analyzed for PRP content before and after exposure to diets adulterated with bitter compounds, including quinine and tannic acid. To isolate the site of exposure necessary for PRP induction rats will also be given tannic acid via either oral or gastric exposure. The ability or inability to induce PRP production is not sufficient to predict interactios between the proteins and the bitter tastants. Therefore, Specific Aim 2 will establish if PRP induction can alter the detection threshold for and superthreshold responsiveness to multiple bitter stimuli. Rats will be used to derive psychophysical detection curves of several bitter tastants in the presence and absence of PRPs. Likewise, responsiveness in the suprathreshold range will be assessed in the presence and absence of PRPs with a series of brief-access tests. Collectively, these experiments will test the hypothesis that PRPs alter taste sensitivity for bittr taste stimuli and ultimately blunt unconditioned taste avoidance responses to these compounds. Together these aims could inform methods for increasing the palatability of healthy phytochemicals and pediatric medicines.

描述（由申请人提供）：苦味感知的变化可能在饮食选择中起关键作用，这对人类健康具有不可思议的影响。尽管苦味物质通常与有毒物质相关，但大量具有营养意义的食物来源含有苦涩的植物化学物质（例如，西兰花[1]，菠菜[2]），其中许多东西具有有益的价值[1，3]，理解苦味的味道和检测到如何理解饮食选择[4]和增加dep sectional of ded Medicine of dedicate nicrict of dediicalictic nicrict of Indiactrict and Intiactrict and tossection toce toce tose taste and toce toce toce toce and toce toce tossive tose的重要性[1，3]。在正常的喂养和饮酒条件下，口味化合物必须不可避免地与唾液混合，然后才能达到其受体靶标，但很少完成工作，研究了唾液蛋白如何调节味道刺激并改变苦味味道感知。所有唾液蛋白中有70％构成了一种称为富含脯氨酸蛋白（PRP）的蛋白质。饮食中的单宁酸会引起大鼠的PRP产生，这是一种定期食用在内的动物，包括人类在内的植物化合物。已经假设PRP通过与单宁与单宁结合而改变单宁酸的可接受性，从而降低了单宁酸溶液的感知强度[10，11]。有证据表明，这些蛋白质可能与其他苦味有类似的关系。它们的生产与苦味受体紧密相邻[13]。 PRP和苦味受体的基因散布在同一染色体上[5]，最后，基因链接研究暗示了PRPS在人类和小鼠中苦得到的作用[15-18]。 具体的目标1将确定长期接触苦味化合物是否会增加PRP的表达，并确定口腔暴露是否是必要的，足以引起诱导。在暴露于苦味的饮食之前和之后，将分析唾液的PRP含量，包括奎宁和单宁酸。为了隔离PRP感应大鼠所需的暴露部位，也将通过口服或胃暴露给单宁酸。诱导PRP产生的能力不足以预测蛋白质与苦味剂之间的相互作用。因此，特定的目标2将确定PRP归纳是否可以改变对多种苦味刺激的检测阈值和超转距的反应。在存在和不存在PRP的情况下，将使用大鼠来得出几种苦味剂的心理物理检测曲线。同样，在存在和不存在一系列简短访问测试的PRP的情况下，将评估上疑范围范围的响应能力。总的来说，这些实验将检验以下假设：PRP改变了对BITTR口味刺激的口味灵敏度，并最终对这些化合物的无条件避免了味道避免反应。这些目标共同为增加健康植物化学物质和小儿药物的可口性提供了信息。