N-aryl-piperidine-4-carboxamides as a novel class of potent inhibitors of MALT1 proteolytic activity

Starting from a weak screening hit, potent and selective inhibitors of the MALT1 protease function were elaborated. Advanced compounds displayed high potency in biochemical and cellular assays. Compounds showed activity in a mechanistic Jurkat T cell activation assay as well as in the B-cell lymphoma line OCI-Ly3, which suggests potential use of MALT1 inhibitors in the treatment of autoimmune diseases as well as B-cell lymphomas with a dysregulated NF-κB pathway. Initially, rat pharmacokinetic properties of this compound series were dominated by very high clearance which could be linked to amide cleavage. Using a rat hepatocyte assay a good in vitro-in vivo correlation could be established which led to the identification of compounds with improved PK properties.     

Pathophysiological consequences of isoform-specific IP3 receptor mutations

Ca²⁺ signaling governs a diverse range of cellular processes and, as such, is subject to tight regulation. A main component of the complex intracellular Ca²⁺-signaling network is the inositol 1,4,5-trisphosphate (IP₃) receptor (IP₃R), a tetrameric channel that mediates Ca²⁺ release from the endoplasmic reticulum (ER) in response to IP₃. IP₃R function is controlled by a myriad of factors, such as Ca²⁺, ATP, kinases and phosphatases and a plethora of accessory and regulatory proteins. Further complexity in IP₃R-mediated Ca²⁺ signaling is the result of the existence of three main isoforms (IP₃R1, IP₃R2 and IP₃R3) that display distinct functional characteristics and properties. Despite their abundant and overlapping expression profiles, IP₃R1 is highly expressed in neurons, IP₃R2 in cardiomyocytes and hepatocytes and IP₃R3 in rapidly proliferating cells as e.g. epithelial cells. As a consequence, dysfunction and/or dysregulation of IP₃R isoforms will have distinct pathophysiological outcomes, ranging from neurological disorders for IP₃R1 to dysfunctional exocrine tissues and autoimmune diseases for IP₃R2 and -3. Over the past years, several IP₃R mutations have surfaced in the sequence analysis of patient-derived samples. Here, we aimed to provide an integrative overview of the clinically most relevant mutations for each IP₃R isoform and the subsequent molecular mechanisms underlying the etiology of the disease.     

Lipid peroxidation assessed by serum thiobarbituric acid reactive substances in healthy subjects and in patients with pathologies known to affect trace element status

Serum thiobarbituric acid reactive substances (TBARS), Zn, Cu, and Se concentrations were determined in 47 healthy adults and in patients with diseases, such as renal in sufficiency, insulin-dependent diabetes mellitus, chronic pancreatitis, liver cirrhosis, or cancer, in order to clarify the relationship between this indicator of lipid peroxidation and antioxidative trace element status. TBARS levels were higher than control values in all pathological cases, except in cancer patients. Cu levels in patients highly correlated with ferroxidase ceruloplasmin activity (r=0.86), but were only statistically different from controls in diabetics. Zn levels were lower than normal in dialysis, liver cirrhosis, and cancer patients. Se levels were significantly decreased in all pathological cases. Half of the subjects with liver cirrhosis or renal insufficiency and 3/4 of chronic pancreatitis or cancer patients had an active inflammatory process. Despite intense modifications in determined indicators, no clear correlation could be demonstrated between the different parameters. Basic antioxidative trace element status and inflammation are therefore not major determinants of TBARS levels in normal and in pathological conditions, despite of the frequent association of low serum Zn and mainly low serum Se with high TBARS levels.     

Oxidative injury to isolated rat pancreatic acinar cells vs. isolated zymogen granules

This study compares the susceptibility of pancreatic acinar cells and zymogen granules against oxidative injury and analyzes the mechanisms involved. Zymogen granules and acinar cells, isolated from rat pancreas, were exposed to a reaction mixture containing xanthine oxidase, hypoxanthine, and chelated iron. Cell function and viability were assessed by various techniques. Trypsin activation was quantified by an Elisa for trypsinogen activating peptide. Integrity of granules was determined by release of amylase. The reaction mixture rapidly generated radicals as assessed by deoxyribose and luminol assays. This oxidative stress caused lysis of granules in a matter of minutes but significant cell death only after some hours. Nevertheless, radicals initiated intracellular vacuolization, morphological damage to zymogen granules and mitochondria, increase in trypsinogen activating peptide, and decrease in ATP already after 5–30 min. Supramaximal caerulein concentrations also caused rapid trypsin activation. Addition of cells but not of granules reduced deoxyribose oxidation, suggesting that intact cells act as scavengers. Caerulein pretreatment only slightly increased the susceptibility of cells but markedly that of granules. In conclusion, isolated zymogen granules are markedly more susceptible to oxidative injury than intact acinar cells, in particular, in early stages of caerulein pancreatitis. The results show that oxidative stress causes a rapid trypsin activation that may contribute to cell damage by triggering autodigestion. Zymogen granules and mitochondria appear to be important targets of oxidative damage inside acinar cells. The series of intracellular events initiated by oxidative stress was similar to changes seen in early stages of pancreatitis.     

Th细胞亚群在自身免疫病的发病及治疗中作用的实验研究进展

本文回顾了Ｔｈ细胞亚群的功能、交互调节、影响其分化的因素以及Ｔｈ细胞亚群在自身免疫病发病中的可能作用;概括了通过调节Ｔｈ细胞亚群来治疗自身免疫病的方法,包括：上调ＣＤ１ｄ治疗、给予相关细胞因子治疗、佐剂治疗、用抗细胞因子、细胞因子受体、ＣＤ４０配体和Ｂ７分子的单克隆抗体治疗以及ＣＴＬＡ和ＣＴＬＡＩｇ治疗。这些方法为自身免疫病的治疗提供了新的思路。     

Soluble expression and purification of the functional interleukin-30 protein in Escherichia coli

Interleukin-30 (IL-30), or IL-27p28, is the α subunit of IL-27 constructed by Epstein–Barr virus-induced gene 3 (EBI3) and IL-27p28 binding via noncovalent bonds. IL-30 can be independently secreted and function independently of IL-27. Recent studies demonstrated IL-30 could concurrently antagonize T helper 1 (Th1) and Th17 responses and might have therapeutic implications for controlling autoimmune diseases. However, no reports have stated an efficient method to generate a relatively large quantity of IL-30. In this study, an Escherichia coli expression system for the rapid expression of the mouse IL-30 is developed. For the first time, IL-30 was expressed in a form of soluble fusion protein and purified using a method of simple affinity chromatography. In order to avoid the impact of minor codons on expressing eukaryotic protein in E. coli and to improve the expression quantity, the nucleotide sequence of IL-30 was optimized. The optimized gene sequence was then subcloned into the pET-44a(+) vector, which allowed expression of IL-30 with a fusion tag, NusA. The vector was transformed into E. coli and the expressed fusion protein, NusA-IL-30, was purified by Ni chromatography. Then the fusion tag was removed by cleavage with thrombin. The purity of purified IL-30 was identified using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) as well as high-performance liquid chromatography (HPLC) and the purity was up to about 92%. The yield of IL-30 was 8.95 mg from 1 L of bacterial culture. Western blot confirmed the identity of the purified protein. The recombinant IL-30 showed its biological activity by inhibiting Th17 differentiating from naive CD4⁺ T cells. Therefore, this method of express and purifying IL-30 provides novel procedures to facilitate structural and functions studies of IL-30.     

肝纤维化程度及自身抗体表达对熊去氧胆酸单药治疗自身免疫性肝病重 叠综合征患者临床疗效的影响

目的:肝纤维化程度及自身抗体表达对熊去氧胆酸单药治疗自身免疫性肝病重叠综合征患者临床疗效的影响。方法:回顾性收集2007年-2011年住院的20例做过肝穿活检的经熊去氧胆酸单药治疗达到满意效果的自身免疫性肝炎和原发性胆汁性肝硬化重叠综合征患者的临床资料。结果:20例患者中,12例患者(60%)的肝穿标本活检评估处于肝纤维化S3或S4期,其初诊时基线特征与肝纤维化处于S0-S2期的患者基线特征无统计学差异。此外,该20例患者的血清抗平滑肌抗体的阳性率较低(1/20)。结论:肝脏纤维化程度不会引起熊去氧胆酸治疗效果的下降。     

A high-throughput sequence analysis of Japanese patients revealed 11 candidate genes associated with type 1 autoimmune pancreatitis susceptibility

The pathogenesis of autoimmune pancreatitis is unknown. In the present study we used high-throughput sequencing with next generation sequencing to identify the candidate genes associated with AIP. A total of 27 type 1 AIP patients and 30 healthy blood donors were recruited, and DNA samples were isolated from their mononuclear cells. A high-throughput sequencer with an original custom panel of 1031 genes was used to detect the genetic variants in each sample. Polymorphisms of CACNA1S (c.4642C>T), rs41554316, rs2231119, rs1042131, rs2838171, P2RX3 (c.195delG), rs75639061, SMAD7 (c.624delC) and TOP1 (c.2007delG), were identified as candidate genetic variants in patients with type 1 AIP. P2RX3 and TOP1 were significantly associated with AIP, even after adjusting bay means of Bonferroni's correction. In addition, we also identified eight candidate genetic variants that were associated with the relapse of type 1 AIP, namely: rs1143146, rs1050716, HLA-C (c.759_763delCCCCCinsTCCCG), rs1050451, rs4154112, rs1049069, CACNA1C (c.5996delC) and CXCR3 (c.630_631delGC). Finally polymorphisms of rs1050716 and rs111493987 were identified as candidate genetic variants associated with extra-pancreatic lesions in patients with type 1 AIP. These candidates might be used as markers of AIP susceptibility and could contribute to the pathogenesis of type 1 AIP.     

Spontaneous immune complex orchitis in Brown Norway rats

Immune complexes occur spontaneously in the testis of Brown-Norway (BN) inbred rats between the basal lamina of the seminiferous tubules and the outer lamina of the myoid testicular cells. The deposits can be detected immunohistologically (IgG; C3) and by electron microscopy. The immune complexes appear between the 8th and 12th weeks of life, increase in amount up to the 30th week and decrease thereafter. After about the 20th week, of life, 15% of the animals show destruction of the germinal epithelium accompanied by an infiltration of lymphocytes and plasma cells. The final stage of this disease, which initially shows no signs of inflammation, is characterized by diffuse tubular atrophy. However, up to the 70th week of life, 85% of the animals with immune complexes show no pathological alterations. Antibodies eluated from the testes react with spermatocytes I and structures close to the lumen of the seminiferous tubules, but not with mature sperms. Serum antibodies to sperms occur in about 25% of the BN rats, but the presence of these antibodies shows no correlation with the immunohistological findings. This newly described spontaneous immune complex orchitis is regarded as a further example of an in-situ-induced immune complex disease. The observations made here can be compared with those in (peri-) membraneous glomerulonephritis, another example of a disorder resulting from in-situ-formation of immune deposits.     

波叶大黄多糖对胰腺五种酶的抑制作用

 本文报道波叶大黄多糖(Rheum hotaoense polysaccharide,RHP)对胰腺五种酶的抑制作用。结果表明。(1)RHP对胰蛋白酶、胰脂肪酶、胰淀粉酶、胰弹性蛋白酶和胰激肽释放酶均有很明显的抑制作用。IC_(50)分别为250μg/mL、21μg/mL、18μg/mL,189μg/mL和300μg/mL。(2)动力学研究表明,RHP对胰蛋白酶和胰脂肪酶的抑制均是非竞争性的,Km值分别为1.2×10~(-4)μmol/mL和1.2mg/mL,Ki值分别为355.0μg/mL和63.85μg/mL。(3)牛血清白蛋白(BSA)对RHP抑制胰蛋白晦和胰脂肪酶具有拮抗作用。当BSA浓度达72.0mg/mL时,对胰蛋白酶活性的恢复率为71.54％。当BSA浓度达20.0mg/mL时,对胰脂肪酶活性的恢复率为63.64％。上述结果表明,RHP对胰腺五种酶的抑制作用,可能是大黄治疗急性胰腺炎作用的生化机制之一,预示RHP在临床上将有重要应用前景。