Arai Chikako, Arai Norie, Arai Shigeyuki, Yoshizane Chiyo, Miyata Satomi, Mizote Akiko, Suyama Aki, Endo Shin, Ariyasu Toshio, Mitsuzumi Hitoshi, Ushio Shimpei
HAYASHIBARA CO. LTD, 675-1 Fujisaki, Naka-ku, Okayama, 702-8006 Japan.
Nutr Metab (Lond). 2019 Jul 16;16:45. doi: 10.1186/s12986-019-0373-4. eCollection 2019.
Trehalose is well known as a functional disaccharide with anti-metabolic activities such as suppression of adipocyte hypertrophy in mice and alleviation of impaired glucose tolerance in humans. Recently, a new type of adipocyte beige cells, involved in so-called white adipocyte tissue (WAT) browning, has received much attention as a target for adaptive thermogenesis. To clarify the relationship between adipocyte hypertrophy suppression and beige cells involved in thermogenesis, we examined the effect of trehalose on the changes in beige adipocytes in mice under normal dietary conditions.
Mice fed a normal diet were administered water containing 0.3% (W/V) trehalose for 16 weeks, 0.3% (W/V) maltose, or water without saccharide (controls). Body temperature and non-fasting blood glucose levels were measured every 3 weeks. After 16 weeks of these treatments, mesenteric and inguinal adipose tissues were collected for measuring adipocyte size, counting the number of UCP1 positive cells by image analysis, and preparing mRNA to analyze beige adipocyte-related gene expression.
Mice administered a continuous intake of trehalose exhibited a thermogenic ability as represented by an increase in rectal temperature, which was maintained at a relatively high level from 3 to 9 weeks and was significantly higher at 15 weeks in comparison with that of the maltose group. In addition to the reduced hypertrophy of mesenteric and inguinal adipose tissues, the trehalose group showed a significant increase in the rates of beige adipocytes in each WAT in comparison with those of the maltose and the water groups. Interestingly, a negative correlation was found between the mean cell sizes of adipocytes and the rates of beige adipocytes in the WAT. Furthermore, real-time PCR showed that the expression of and mRNAs, which are markers for beige adipocytes in the inguinal adipose tissue, increased in the trehalose group.
Continuous administration of trehalose to mice fed a normal diet induced WAT browning accompanied by suppression of white adipocyte hypertrophy, elevated body temperature and decreased blood glucose levels, which resulted in enhancement of energy metabolism. Therefore, we propose trehalose as a new type of thermogenic dietary component to prevent obesity by promoting WAT browning.
海藻糖是一种众所周知的功能性二糖，具有抗代谢活性，如抑制小鼠脂肪细胞肥大和缓解人类糖耐量受损。最近，一种新型的脂肪细胞米色细胞，参与所谓的白色脂肪组织（WAT）褐变，作为适应性产热的靶点受到了广泛关注。为了阐明脂肪细胞肥大抑制与参与产热的米色细胞之间的关系，我们研究了海藻糖在正常饮食条件下对小鼠米色脂肪细胞变化的影响。
给正常饮食的小鼠分别给予含0.3%（W/V）海藻糖的水16周、0.3%（W/V）麦芽糖的水或不含糖类的水（对照组）。每3周测量一次体温和非空腹血糖水平。在这些处理16周后，收集肠系膜和腹股沟脂肪组织，用于测量脂肪细胞大小、通过图像分析计数UCP1阳性细胞数量以及制备mRNA以分析米色脂肪细胞相关基因表达。
持续摄入海藻糖的小鼠表现出产热能力，表现为直肠温度升高，在3至9周维持在相对较高水平，与麦芽糖组相比，在15周时显著更高。除了肠系膜和腹股沟脂肪组织肥大减轻外，与麦芽糖组和水组相比，海藻糖组各WAT中米色脂肪细胞的比例显著增加。有趣的是，在WAT中脂肪细胞的平均细胞大小与米色脂肪细胞的比例之间发现了负相关。此外，实时PCR显示，腹股沟脂肪组织中作为米色脂肪细胞标志物的 和 mRNA的表达在海藻糖组中增加。
给正常饮食的小鼠持续给予海藻糖可诱导WAT褐变，同时抑制白色脂肪细胞肥大、提高体温并降低血糖水平，从而增强能量代谢。因此，我们提出海藻糖作为一种新型的产热饮食成分，通过促进WAT褐变来预防肥胖。
