Human Antigen Leucocyte (HLA)-G and HLA-E are differentially expressed in pancreatic disorders.

BACKGROUND: Little information is available regarding the expression of the immunomodulatory Human Leukocyte Antigen (HLA)-G and -E molecules in pancreatic disorders. AIM: To analyze HLA-G and -E expression in specimens of alcoholic chronic pancreatitis (ACP), idiopathic chronic pancreatitis (ICP), type 1 (T1D) and type 2 diabetes (T2D) and in histologically normal pancreas (HNP). METHODS: HLA-G and -E expression (ACP = 30, ICP = 10, T1D = 10, T2D = 30 and HNP = 20) was evaluated by immunohistochemistry in three different areas (acini, islets and inflammatory infiltrate). RESULTS: Acini and islets from HNP specimens exhibited higher HLA-G and -E expression compared to corresponding areas from all other patient groups. In inflammatory infiltrate, HLA-G and -E expression was observed only among the pancreatic disorders. We observed higher HLA-G and -E expression in acini from T2D compared to ACP, as well as higher HLA-G expression compared to ICP. CONCLUSION: The decreased expression of HLA-G and -E in islets and acini together with the expression of these molecules in the inflammatory infiltrating cells were shared features among chronic inflammatory and autoimmune pancreatic disorders evaluated in this study, possibly reflecting tissue damage.

The comparative efficacy of renin-angiotensin system blockers in schistosomal hepatic fibrosis.

Schistosomiasis mansoni is involved in hepatic fibrogenesis and portal hypertension. Previous studies proved that blockade of some components of the renin-angiotensin system (RAS) reduce liver fibrogenesis. However, the effects of inhibition of early stages of RAS pathway in schistosomal fibrosis have not been studied yet. Thus, the aim of this study was to compare the role of different antihypertensive drugs on hepatic fibrosis in murine schistosomiasis. BALB/c mice (n = 50) weighing 20g were subjected to inoculation of 50 cercariae and submitted to different treatments: aliskiren, 50 mg/kg (n = 10); bradykinin, 2 µg/kg (n = 5); losartan, 10 mg/kg (n = 10); lisinopril 10 mg/kg (n = 5) and control, proportional volume vehicle (n = 5); daily for 14 weeks. Six animals were not subjected to cercariae inoculation or any type of treatment. Ultrasound, histological, immunohistochemical and proteomic analyzes were performed to evaluate markers associated with hepatic fibrogenesis. The hepatic areas stained with Sirius red and thenumber of cells marked by α-SMA in animals treated with aliskiren, bradykinin, lisinopril and losartan were diminished when compared to control group, demonstrating reduced hepatic fibrosis after RAS blockade. These results were reinforced by ultrasonography analysis and protein expression of TGFß. These findings demonstrated the effect of RAS inhibition on hepatic fibrosis in murine schistosomiasis, with the most evident results being observed in the losartan and aliskiren treated groups. The main mechanisms underlying this process appear to involve anti-fibrogenic activity through the inhibition of collagen and TGFß synthesis.

Nonalcoholic Steatohepatitis: A Search for Factual Animal Models.

Nonalcoholic fatty liver disease (NAFLD) is characterized by hepatic steatosis, which occurs in the absence of alcohol abuse. NAFLD can evolve into progressive liver injury and fibrosis in the form of nonalcoholic steatohepatitis (NASH). Several animal models have been developed to attempt to represent the morphological, biochemical, and clinical features of human NASH. The actual review presents a critical analysis of the most commonly used experimental models of NAFLD/NASH development. These models can be classified into genetic, nutritional, and a combination of genetic and nutritional factors. The main genetic models are ob/ob and db/db mutant mice and Zucker rats. The principal nutritional models employ methionine- and choline-deficient, high-fat, high-cholesterol and high-cholate, cafeteria, and high-fructose diets. Currently, associations between high-fructose and various compositions of high-fat diets have been widely studied. Previous studies have encountered significant difficulties in developing animal models capable of reproducing human NASH. Some models produce consistent morphological findings, but the induction method differs significantly compared with the pathophysiology of human NASH. Other models precisely represent the clinical and etiological contexts of this disease but fail to provide accurate histopathological representations mainly in the progression from steatosis to liver fibrosis.