Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Japan.
Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan.
PLoS One. 2021 Mar 17;16(3):e0248065. doi: 10.1371/journal.pone.0248065. eCollection 2021.
Excessive sodium salt (NaCl) or fat intake is associated with a variety of increased health risks. However, whether excessive NaCl intake accompanied by a high-fat diet (HFD) affects glucose metabolism has not been elucidated. In this study, C57BL/6J male mice were fed a normal chow diet (NCD), a NCD plus high-NaCl diet (NCD plus NaCl), a HFD, or a HFD plus high-NaCl diet (HFD plus NaCl) for 30 weeks. No significant differences in body weight gain, insulin sensitivity, and glucose tolerance were observed between NCD-fed and NCD plus NaCl-fed mice. In contrast, body and liver weights were decreased, but the weight of epididymal white adipose tissue was increased in HFD plus NaCl-fed compared to HFD-fed mice. HFD plus NaCl-fed mice had lower plasma glucose levels in an insulin tolerance test, and showed higher plasma glucose and lower plasma insulin levels in an intraperitoneal glucose tolerance test compared to HFD-fed mice. The β-cell area and number of islets were decreased in HFD plus NaCl-fed compared to HFD-fed mice. Increased Ki67-positive β-cells, and increased expression levels of Ki67, CyclinB1, and CyclinD1 mRNA in islets were observed in HFD-fed but not HFD plus NaCl-fed mice when compared to NCD-fed mice. Our data suggest that excessive NaCl intake accompanied by a HFD exacerbates glucose intolerance, with impairment in insulin secretion caused by the attenuation of expansion of β-cell mass in the pancreas.
过量的钠盐（NaCl）或脂肪摄入与多种健康风险增加有关。然而，过量的 NaCl 摄入伴随着高脂肪饮食（HFD）是否会影响葡萄糖代谢尚未阐明。在这项研究中，C57BL/6J 雄性小鼠分别喂食正常饲料（NCD）、NCD 加高 NaCl 饮食（NCD 加 NaCl）、高脂肪饮食（HFD）或 HFD 加高 NaCl 饮食（HFD 加 NaCl）30 周。与 NCD 喂养组相比，NCD 加 NaCl 喂养组的体重增加、胰岛素敏感性和葡萄糖耐量没有显著差异。相比之下，与 HFD 喂养组相比，HFD 加 NaCl 喂养组的体重和肝脏重量降低，但附睾白色脂肪组织的重量增加。与 HFD 喂养组相比，HFD 加 NaCl 喂养组在胰岛素耐量试验中血糖水平较低，在腹腔葡萄糖耐量试验中血糖水平较高，胰岛素水平较低。与 HFD 喂养组相比，HFD 加 NaCl 喂养组胰岛β细胞面积和胰岛数量减少。与 NCD 喂养组相比，HFD 喂养组但不是 HFD 加 NaCl 喂养组的胰岛中 Ki67 阳性β细胞增加，Ki67、CyclinB1 和 CyclinD1mRNA 的表达水平升高。我们的数据表明，HFD 伴随着过量的 NaCl 摄入可加剧葡萄糖不耐受，导致胰岛β细胞质量扩张减弱，从而损害胰岛素分泌。
