Effects of oral Lactobacillus plantarum on hepatocyte tight junction structure and function in rats with obstructive jaundice

Surgery and infection are prominent risk factors for the development of obstructive cholestasis which in turn is associated with failure of the liver barrier. We studied the effects of oral Lactobacillus plantarum (LP) supplementation on endotoxemia, oxidative stress, apoptosis, and tight junctions of hepatocytes in an experimental model of obstructive jaundice. Fifty male Wistar rats were randomly divided into five groups of 10 each: group I, sham-operated; group II, ligation and division of the common bile duct (BDL); group III, BLD followed by oral LP treatment; group IV, BDL followed by internal biliary drainage (IBD); group V, BDL followed by IBD and oral LP treatment. Hepatocyte apoptosis, plasma reduced glutathione (GSH) and oxidized glutathione (GSSG) levels, and portal blood endotoxin levels were measured and changes in tight junction-associated proteins occludin, claudin-1, claudin-4, and ZO-1 were observed. Compared to the sham-operated group I, significant increases in endotoxemia, apoptosis, and GSSG were observed in group II and significant decreases were observed in group V. Tight junctions were destroyed in group II animals but were not in animals treated with oral LP (groups III and V). An increase in occludin, claudin-1, claudin-4, and ZO-1 mRNA and protein levels were detected in livers in LP-treated animals (group V) compared with group II levels. Oral LP treatment of rats with obstructive jaundice assisted in the return of active hepatic barrier function. These results may lead to treatments to prevent the deleterious effects of obstructive jaundice.

Effect of oral glutamine administration on bacterial tanslocation, endotoxemia, liver and ileal morphology, and apoptosis in rats with obstructive jaundice

Postoperative complications in patients with obstructive jaundice remain increased when associated with endotoxemia and the inflammatory response due to gut barrier failure. Administration of glutamine has been proposed to maintain the integrity of the gut mucosa and thus reduce bacterial translocation (BT), but the effects of this pretreatment on apoptosis and histologic morphology of various organs affected by BT in obstructive jaundice have not been studied. We therefore studied the effects of oral glutamine supplementation on endotoxemia, BT, liver and terminal ileal morphology, and apoptosis in an experimental model of obstructive jaundice. A total of 60 male Wistar rats were randomly divided into four groups of 15 each: I, controls; II, sham-operated; III, bile duct ligation (BDL); IV, BDL + glutamine (4.5 g/kg/day in drinking water). Ileal samples for histology, DNA and protein content, liver biopsies, mesenteric lymph nodes (MLNs) for culture, and portal and systemic blood samples for endotoxin measurements were obtained 10 days later. Compared to the controls, a significant increase in contaminated MLN and liver samples and increased endotoxemia were noted in group III (p < 0.01) but were significantly reduced in group IV (p < 0.05). Group IV also had a significantly higher number of mitoses per crypt (M/c) (p < 0.05), less apoptotic body counts (ABCs) (p < 0.05), and a higher DNA content than did group III (p < 0.05). Liver biopsies from group III displayed typical changes of large duct obstruction that significantly improved after glutamine treatment, with decreased ductular proliferation. We concluded that supplementation of oral glutamine in the presence of obstructive jaundice ameliorates BT, endotoxemia, and apoptosis and improves the ileal and liver histology.