Department of Gastroenterology and Metabology, Ehime University Graduate School of Medicine, Ehime, Japan.
Am J Clin Nutr. 2012 Jul;96(1):90-101. doi: 10.3945/ajcn.111.033084. Epub 2012 May 30.
Dietary long-chain fatty acid (LCFA) intake is an important risk factor for hepatic inflammation and hepatocarcinogenesis. An alternate route of dietary LCFA absorption has been suggested in patients with liver cirrhosis (LC).
We aimed to determine this alternate route and to identify its mechanism.
Twenty healthy control subjects and 47 patients with LC-n = 23 with portal hypertension [PH(+)LC] and 24 without portal hypertension [PH(-)LC)]-were enrolled. [¹³C]Palmitate (an LCFA) and octanoate (a medium-chain fatty acid [MCFA]) were administered by using gastrointestinal endoscopy. Breath ¹³CO₂ was measured to quantify metabolized fatty acids. We also examined intestinal specimens of patients in these groups.
A more rapid increase in metabolized palmitate, which showed a pattern similar to that of octanoate metabolism, was observed in patients with LC than in healthy control subjects. The increase in the PH(-)LC group was higher than that in the PH(+)LC group. However, the concentration of metabolized palmitate increased with treatment of the PH(+)LC group with a portal-systemic shunt. Morphologic changes such as expanded lymph and blood vessels were present, and glycosylated CD36 increased in the jejunum of the PH(+)LC group. This group had high serum concentrations of glucagon-like peptide-2. These data suggest that dietary LCFAs, similar to MCFAs, are absorbed via blood vessels in patients with LC.
Rapid absorption of LCFAs by an alternative method occurred in patients with LC. This altered LCFA processing is likely related to upregulation of intestinal glycosylated CD36 and could contribute to pathogenesis in patients with LC.
膳食长链脂肪酸(LCFA)的摄入是肝炎症和肝癌发生的一个重要危险因素。有研究提出,肝硬化(LC)患者可能存在一种替代的膳食 LCFA 吸收途径。
我们旨在确定这种替代途径,并确定其机制。
共纳入 20 名健康对照者和 47 例 LC 患者[23 例伴门静脉高压(PH(+)LC),24 例不伴门静脉高压(PH(-)LC)]。通过胃肠内镜给予[¹³C]棕榈酸(LCFA)和辛酸(中链脂肪酸[MCFA])。测量呼气 ¹³CO₂以定量代谢脂肪酸。我们还检查了这些组患者的肠道标本。
与健康对照者相比,LC 患者的代谢棕榈酸增加更快,其模式类似于辛酸代谢。PH(-)LC 组的增加高于 PH(+)LC 组。然而,在用门体分流术治疗 PH(+)LC 组后,代谢棕榈酸的浓度增加。在 PH(+)LC 组的空肠中存在形态学变化,如扩张的淋巴管和血管,糖基化 CD36 增加。该组的胰高血糖素样肽-2 血清浓度较高。这些数据表明,膳食 LCFA 与 MCFA 相似,可通过 LC 患者的血管吸收。
LC 患者通过替代方法快速吸收 LCFA。这种改变的 LCFA 处理可能与肠道糖基化 CD36 的上调有关,并可能导致 LC 患者的发病机制。