Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan.
Department of Animal Science, Michigan State University, East Lansing, Michigan.
Am J Physiol Gastrointest Liver Physiol. 2022 Mar 1;322(3):G346-G359. doi: 10.1152/ajpgi.00207.2021. Epub 2022 Jan 5.
Early-life adversity (ELA) is linked with the increased risk for inflammatory and metabolic diseases in later life, but the mechanisms remain poorly understood. Intestinal epithelial glucose transporters sodium-glucose-linked transporter 1 (SGLT1) and glucose transporter 2 (GLUT2) are the major route for intestinal glucose uptake but have also received increased attention as modulators of inflammatory and metabolic diseases. Here, we tested the hypothesis that early weaning (EW) in pigs, an established model of ELA, alters the development of epithelial glucose transporters and coincides with elevated markers of metabolic inflammation. The jejunum and ileum of 90-day-old pigs previously exposed to EW (16 days wean age), exhibited reduced SGLT1 activity (by ∼ 30%, < 0.05) than late weaned (LW, 28 days wean age) controls. In contrast, GLUT2-mediated glucose transport was increased ( = 0.003) in EW pigs than in LW pigs. Reciprocal changes in SGLT1- and GLUT2-mediated transport coincided with transporter protein expression in the intestinal brush-border membranes (BBMs) that were observed at 90 days and 150 days of age. Ileal SGLT1-mediated glucose transport and BBM expression were inhibited by the β-adrenergic receptor (βAR) blocker propranolol in EW and LW pigs. In contrast, propranolol enhanced ileal GLUT2-mediated glucose transport ( = 0.015) and brush-border membrane vesicle (BBMV) abundance ( = 0.035) in LW pigs, but not in EW pigs. Early-weaned pigs exhibited chronically elevated blood glucose and C-reactive protein (CRP) levels, and adipocyte hypertrophy and upregulated adipogenesis-related gene expression in visceral adipose tissue. Altered development of intestinal glucose transporters by EW could underlie the increased risk for later life inflammatory and metabolic diseases. These studies reveal that early-life adversity in the form of early weaning in pigs causes a developmental shift in intestinal glucose transport from SGLT1 toward GLUT2-mediated transport. Early weaning also induced markers of metabolic inflammation including persistent elevations in blood glucose and the inflammatory marker CRP, along with increased visceral adiposity. Altered intestinal glucose transport might contribute to increased risk for inflammatory and metabolic diseases associated with early-life adversity.
早期生活逆境(ELA)与晚年炎症和代谢性疾病的风险增加有关,但机制仍知之甚少。肠道上皮葡萄糖转运体钠-葡萄糖协同转运蛋白 1(SGLT1)和葡萄糖转运蛋白 2(GLUT2)是肠道葡萄糖摄取的主要途径,但作为炎症和代谢性疾病的调节剂也受到了越来越多的关注。在这里,我们测试了这样一个假设,即在猪中,一种已建立的 ELA 模型,早期断奶(EW)改变了上皮葡萄糖转运体的发育,并与代谢性炎症的升高标志物同时发生。与晚断奶(LW,28 天断奶年龄)对照组相比,先前暴露于 EW(16 天断奶年龄)的 90 天大猪的空肠和回肠中 SGLT1 活性降低(约 30%,<0.05)。相比之下,EW 猪的 GLUT2 介导的葡萄糖转运增加(=0.003)。肠道刷状缘膜(BBM)中 SGLT1 和 GLUT2 介导的转运的这种相互变化的变化与 90 天和 150 天的肠道吸收蛋白表达一致。在 EW 和 LW 猪中,β-肾上腺素能受体(βAR)阻滞剂普萘洛尔抑制回肠 SGLT1 介导的葡萄糖转运和 BBM 表达。相比之下,普萘洛尔增强了 LW 猪而非 EW 猪的回肠 GLUT2 介导的葡萄糖转运(=0.015)和刷状缘膜囊泡(BBMV)丰度(=0.035)。早期断奶的猪表现出慢性高血糖和 C 反应蛋白(CRP)水平升高,以及内脏脂肪组织中脂肪细胞肥大和脂肪生成相关基因表达上调。EW 导致的肠道葡萄糖转运的发育变化可能是晚年炎症和代谢性疾病风险增加的基础。这些研究表明,以早期断奶形式出现的早期生活逆境导致肠道葡萄糖转运从 SGLT1 向 GLUT2 介导的转运发生发育性转变。早期断奶还诱导了代谢性炎症标志物,包括血糖持续升高和炎症标志物 CRP 升高,以及内脏脂肪增加。肠道葡萄糖转运的改变可能导致与早期生活逆境相关的炎症和代谢性疾病风险增加。