Histopathological characteristics of liver biopsy performed at different time points in drug-induced liver injury.

BACKGROUND AND AIMS: Liver biopsy can provide critical information in patients with drug-induced liver injury (DILI). Our study aimed to compare the histopathological features of DILI at different time points from the onset to liver biopsy. METHODS: We conducted a single-centre retrospective observational study. The clinical and follow-up data were extracted, and the pathological slides were reviewed. RESULTS: 129 patients were included. The median age was 52 and 75% were women. They were divided into <1 month, 1-3 months, and >3 months groups according to the durations from onset of the disorder to liver biopsy. The aminotransferase, alkaline phosphatase, and bilirubin levels showed no significant differences at onset but significantly decreased with time among the three groups (all p<0.05) at the time of liver biopsy. Histological injury patterns were significantly different among the three groups (p<0.01). Hepatocellular, canalicular, and cholestasis of Kupffer cells were significantly less frequent in the >3 months group (p<0.01). For patients taking herbs, bridging necrosis and cholestatic injury were significantly more frequent in the <1 month group (p<0.01). Furthermore, ductopenia, cholate stasis, and foam-like cells were equally distributed in the three groups but were significantly associated with poor prognosis. CONCLUSIONS: Biopsy time significantly affects liver pathology: the earlier, the more acute cholestatic-hepatitic pattern, the later, the more chronic injury patterns. The prognostic features (ductopenia, cholate stasis, and foam-like cells) occurred equally in all three groups. Our study provides valuable information for liver pathologists aiding in their better interpretation of the liver biopsy from patients with DILI.

Hypocholesterolemic and choleretic effects of three dimethoxycinnamic acids in relation to 2,4,5-trimethoxycinnamic acid in rats fed with a high-cholesterol/cholate diet.

BACKGROUND: 2,4,5-Trimethoxycinnamic acid (2,4,5-TMC) is the major and non-toxic metabolite of α-asarone, which retains hypocholesterolemic and choleretic activities. We compared the activities of 2,4,5-TMC with those of 2,4-dimethoxycinnamic acid (2,4-DMC), 3,4-DMC and 3,5-DMC, to understand the role of the methoxyls on carbons 2, 4 and 5 on the pharmacologic properties of these compounds. METHODS: The methoxycinnamic acids were administered to high-cholesterol/cholate-fed rats. We measured bile flow, and quantified bile acids, phospholipids and cholesterol in bile, and cholesterol and cholesterol-lipoproteins in serum. The inhibition of HMG-CoA reductase by the methoxycinnamic acids was evaluated in vitro. RESULTS: The four methoxycinnamic acids decreased serum cholesterol, without affecting the concentration of HDL-cholesterol. 2,4,5-TMC produced the highest decrease in LDL-cholesterol, 73.5%, which exceeds the range of statins (20-40%), and produced the highest inhibition of the activity of HMG-CoA reductase. 3,4-DMC produced the highest increase in bile flow, bile acids and phospholipids concentrations, and reduction in bile cholesterol, which led to a decrease in the biliary cholesterol saturation index. CONCLUSIONS: 2,4,5-TMC (which has three methoxyls) had the highest hypocholesterolemic activity, while 3,4-DMC, which lacks the methoxyl in carbon 2 but conserves the two other methoxyls in an adjacent position, had the highest choleretic activity and a probable cholelitholytic activity. In methoxycinnamic acids with two methoxyls in non-adjacent positions (2,4-DMC and 3,5-DMC), the hypocholesterolemic and choleretic activities were not as evident. 2,4,5-TMC and 3,4-DMC, which did not cause liver damage during the treatment period, should be further explored as a hypocholesterolemic and choleretic compounds in humans.

The effects of diet on occlusive coronary artery atherosclerosis and myocardial infarction in scavenger receptor class B, type 1/low-density lipoprotein receptor double knockout mice.

OBJECTIVE: Deficiency of the high-density lipoprotein receptor, scavenger receptor class B, type I (SR-BI), in apolipoprotein E knockout or hypomorphic mice, respectively, results in spontaneous or diet-inducible occlusive coronary artery (CA) atherosclerosis, myocardial infarction, and early death. Here, we examine effects of SR-BI deficiency on cardiovascular phenotypes in low-density lipoprotein receptor (LDLR) knockout mice fed different atherogenic diets. APPROACH AND RESULTS: SR-BI/LDLR double knockout and control LDLR knockout mice were fed atherogenic diets containing different amounts of fat, cholesterol, and sodium cholate. Double knockout mice fed atherogenic diets high in cholesterol exhibited significantly reduced survival compared with LDLR knockout mice fed the same diets. In addition to increased diet-accelerated aortic sinus atherosclerosis, we observed significant diet-induced CA atherosclerosis in double knockout mice and diet-dependent accumulation of platelets in CA atherosclerotic plaques. This was accompanied by substantial myocardial fibrosis in double knockout mice fed high cholesterol diets. Atherogenic diet fed double knockout mice also exhibited higher circulating cytokine levels, monocytosis with increased proportions of Ly6C(hi) and Ly6C(int) monocytes, and higher adhesion molecule expression in CA endothelial cells compared with control LDLR knockout mice. CONCLUSIONS: Diet-accelerated atherosclerosis and occlusive, platelet-rich CA disease in SR-BI/LDLR double knockout mice is affected by amounts of cholesterol and cholate in atherogenic diets and is accompanied by increased expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 in CAs and increased Ly6C(hi) and Ly6C(int) monocytes in circulation. The increased vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 in CA endothelial cells in SR-BI-deficient mice likely explains their increased susceptibility to atherosclerosis in CAs.

Novel anti-inflammatory functions for endothelial and myeloid cyclooxygenase-2 in a new mouse model of Crohn's disease.

Cyclooxygenase-2 (COX-2) is an important regulator of inflammation implicated in the development of a variety of diseases, including inflammatory bowel disease (IBD). However, the regulation of intestinal inflammation by COX-2 is poorly understood. We previously reported that COX-2(-/-) mice fed a cholate-containing high-fat (CCHF) diet had high mortality of unknown mechanisms attributable to severe intestinal inflammation in the ileo-ceco-colic junction that presented characteristics similar to Crohn's disease (CD). To further characterize the role of COX-2 in intestinal inflammation, we established cell-specific conditional COX-2(-/-) mice. Endothelial cell-specific (COX-2(-E/-E)) and myeloid cell-specific (COX-2(-M/-M)) COX-2(-/-) mice, but not wild-type mice, on the CCHF diet developed localized CD-like pathology at the ileo-ceco-colic junction that was associated with cellular infiltration, increased expression of myeloperoxidase and IL-5, and decreased IL-10 expression. The CD-like pathology in COX-2(-E/-E) mice was also accompanied by increased expression of cytokines (IL-6, TNF-alpha, and INF-gamma), compared with wild-type mice and COX-2(-M/-M) mice. In contrast, the ileo-ceco-colic inflammation in COX-2(-M/-M) mice was associated with more pronounced infiltration of granulocytes and macrophages than COX-2(-E/-E) mice. COX-2(-ME/-ME) (COX-2(-M/-M) x COX-2(-E/-E)) mice on the CCHF diet developed CD-like pathology in the ileo-ceco-colic junction reminiscent of total COX-2(-/-) mice on CCHF diet and wild-type mice on CCHF diet treated with COX-2 inhibitor, celecoxib. The pathology of diet-mediated ileo-ceco-colic inflammation in COX-2(-/-) mice offers an excellent model system to elucidate the protective roles of endothelial and myeloid COX-2 and the molecular pathogenesis of CD.

Atherogenic diet causes lethal ileo-ceco-colitis in cyclooxygenase-2 deficient mice.

Cyclooxygenases (COX) regulate a variety of inflammatory diseases, including inflammatory bowel disease (IBD). While the pathological effects of COX-1 inhibition by NSAIDs on intestinal ulceration are well established, the role of COX-2 on intestinal inflammation remains under investigation. In this paper, we report a protective role for COX-2 against diet-mediated intestinal inflammation in mice. COX-2(-/-) mice fed an atherogenic diet or diet containing cholate, but not chow or fat alone, had a high mortality whereas COX-1(-/-) mice and wild-type mice were unaffected by the dietary changes. Histological analysis identified the cause of death in COX-2(-/-) mice due to severe intestinal inflammation that was surprisingly limited to the ileo-ceco-colic junction. COX-2 expression is induced in the cecum of wild-type mice fed an atherogenic diet. Our findings show that COX-2 plays an anti-inflammatory role at the ileo-ceco-colic junction in mice, and the pathology of diet-mediated intestinal inflammation in COX-2(-/-) mice offers an excellent model system to elucidate the molecular mechanisms of intestinal inflammation.