Buddington Randal K, Bering Stine B, Thymann Thomas, Sangild Per T
Department of Health and Sports Sciences, University of Memphis, Memphis, Tennessee 39152, USA.
Pediatr Res. 2008 Apr;63(4):382-7. doi: 10.1203/PDR.0b013e318165bfed.
Necrotizing enterocolitis (NEC) causes morbidity and mortality among preterm infants and is associated with nutrient malabsorption. Therefore, a preterm pig model that spontaneously develops NEC was used to investigate the relationship between severity of NEC lesions and galactose absorption in vivo and carrier-mediated glucose absorption by intact mid small intestine. Preterm pigs collected by caesarian section at 92% of gestation received parenteral nutrition with and without minimal enteral nutrition for 48 h before conversion to enteral nutrition with colostrum or an enteral formula. Pigs were killed when symptoms of NEC were observed or after 36-40 h of enteral nutrition. NEC lesions decreased in vivo absorption of galactose and mannitol by more than 50% and abolished carrier-mediated glucose uptake by tissues with lesions. Moreover, when NEC lesions were restricted to the colon, small intestinal tissues that seemed clinically healthy had decreased in vitro glucose absorption due to reduced uptake via the sodium-dependent glucose transporter with little or no involvement of the apical facilitative glucose carrier. The present findings reveal a direct relationship between the severity of NEC lesions and the magnitude of sugar malabsorption that is detectable before clinical symptoms are evident.
坏死性小肠结肠炎(NEC)导致早产儿发病和死亡,并与营养吸收不良相关。因此,利用自发发生NEC的早产猪模型来研究NEC病变严重程度与体内半乳糖吸收以及完整中小肠载体介导的葡萄糖吸收之间的关系。在妊娠92%时通过剖腹产收集的早产猪,在转换为初乳或肠内配方奶进行肠内营养之前,接受48小时的肠外营养,有无少量肠内营养。当观察到NEC症状或肠内营养36 - 40小时后,将猪处死。NEC病变使体内半乳糖和甘露醇的吸收减少超过50%,并消除了病变组织中载体介导的葡萄糖摄取。此外,当NEC病变局限于结肠时,临床上看似健康的小肠组织因通过钠依赖性葡萄糖转运体的摄取减少而导致体外葡萄糖吸收减少,而顶端易化葡萄糖载体几乎没有参与或没有参与。目前的研究结果揭示了NEC病变严重程度与在临床症状明显之前即可检测到的糖吸收不良程度之间的直接关系。