High alanine aminotransferase level as a predictor for the incidence of macrovascular disease in type 2 diabetic patients with fatty liver disease

Purpose

We investigated whether fatty liver (FL) disease in type 2 diabetic mellitus (T2DM) patients affects their incidence of macrovascular disease. In addition, we detected a useful marker for predicting the incidence of macrovascular disease events.

Methods

A total of 458 patients who underwent abdominal ultrasonography (US) between April 2003 and March 2004 in a diabetic clinic were divided into FL (n = 211) and non-FL (NFL; n = 247) groups, and followed by a diabetologist and/or hepatologist for 5 years.

Results

No significant difference in the incidence of macrovascular disease, neither cerebrovascular disease nor coronary heart disease, was observed between FL and NFL patients. Interestingly, in FL diabetic patients, only an alanine aminotransferase (ALT) level ≥30 IU/l was significantly associated with the incidence of macrovascular events in univariate (odds ratio [OR], 10.632; 95 % confidence interval [CI], 1.302–86.841; p = 0.0274) and multivariate (OR, 10.134; CI 1.223–83.995; p = 0.0318) analyses. Patients with higher ALT levels had a higher cumulative incidence of macrovascular disease events than did those with lower ALT levels (p = 0.0068). In conclusion, an ALT level ≥30 IU/l is an independent risk indicator of macrovascular disease in diabetic patients with FLD, whereas the presence of FL itself in T2DM patients is not associated with an increased incidence of macrovascular events.

Conclusions

Our findings indicate that therapeutic interventions may be necessary for FL patients with high ALT levels to prevent macrovascular disease.     

Bax-inhibiting peptide protects glutamate-induced cerebellar granule cell death by blocking Bax translocation

Glutamate-induced excitotoxicity has been implicated in the pathogenesis of various neurological damages and disorders. In the brain damage of immature animals such as neonatal hypoxic-ischemic brain injury, the excitotoxicity appears to be more intimately involved through apoptosis. Bax, a member of the Bcl-2 family proteins, plays a key role in the promotion of apoptosis by translocation from the cytosol to the mitochondria and the release of apoptogenic factors such as cytochrome c. Recently, Bax-inhibiting peptide (BIP), a novel membrane-permeable peptide which can bind Bax in the cytosol and inhibit its translocation to the mitochondria, was developed. To investigate the possibility of a new neuroprotection strategy targeting Bax translocation in glutamate-induced neuronal cell death, cerebellar granule neurons (CGNs) were exposed to glutamate with or without BIP. Pretreatment of CGNs with BIP elicited a dose-dependent reduction of glutamate-induced neuronal cell death as measured by MTT assay. BIP significantly suppressed both the number of TUNEL-positive cells and the increase in caspases 3 and 9 activities induced by glutamate. In addition, immunoblotting after subcellular fractionation revealed that BIP prevented the glutamate-induced Bax translocation to the mitochondria and the release of cytochrome c from the mitochondria. These results suggest that agents capable of inhibiting Bax activity such as BIP might lead to new drugs for glutamate-related diseases in the future.     

Structural characterization of bioengineered human corneal endothelial cell sheets fabricated on temperature-responsive culture dishes

For the purpose of corneal regenerative medicine, we fabricated human corneal endothelial cell sheets on temperature-responsive dishes, which could be non-invasively harvested as intact, transplantable sheets by simply reducing the culture temperature. Cells demonstrated hexagonal cell shape with numerous microvilli and cilia, and also exhibited abundant cytoplasmic organelles similar to these cells in vivo. Immunofluorescence for type IV collagen and fibronectin revealed that abundant extracellular matrix (ECM) was deposited on the basal surface throughout culture, and the deposited ECM was harvested along with the cell sheets by reducing culture temperature to 20 degrees C. Faint ECM remnants were observed on the dish surfaces after cell sheet detachment. Immunofluorescence for ZO-1 showed that tight junctions were established between cells, and immunoblotting indicated that intact ZO-1 was maintained during cell sheet harvest, while conventional proteolytic cell harvest methods resulted in the degradation of ZO-1. These results suggest that these transplantable corneal endothelial cell sheets can be applied to treat patients with damaged corneas.     

反义Ku70在人肺癌细胞的表达及对放射线的敏感性研究

目的：研究反义Ku70在人肺癌细胞的表达及对放射线的超敏效应。方法：采用Western-boltting法证明,Ku70－LCA中Ku70蛋白的表达情况,采用体外放线敏感实验症明,反义Ku70在人肺癌细胞的表达及对放射线的超敏效就,其结果以细胞存活克隆率和剂量效应曲线表示,结果：（1）对照组和人正义Ku70基因的LCA组细胞可见Ku70蛋白表达印迹,导入反义Ku70基因LCA组细胞未见Ku70蛋白表达印迹,（2）导入反义Ku70基因的LCA组细胞对放线的敏感性明显增强（P＜0．01）,并呈剂量依赖性,结论：反义Ku70封闭了肿瘤细胞的正义Ku70蛋白表达后,对放坶呈超敏感效应,为提高肿瘤放疗的特异性的靶向基因治疗奠定了基础。     

Host prostaglandin E(2)-EP3 signaling regulates tumor-associated angiogenesis and tumor growth

Nonsteroidal antiinflammatories are known to suppress incidence and progression of malignancies including colorectal cancers. However, the precise mechanism of this action remains unknown. Using prostaglandin (PG) receptor knockout mice, we have evaluated a role of PGs in tumor-associated angiogenesis and tumor growth, and identified PG receptors involved. Sarcoma-180 cells implanted in wild-type (WT) mice formed a tumor with extensive angiogenesis, which was greatly suppressed by specific inhibitors for cyclooxygenase (COX)-2 but not for COX-1. Angiogenesis in sponge implantation model, which can mimic tumor-stromal angiogenesis, was markedly suppressed in mice lacking EP3 (EP3(-/-)) with reduced expression of vascular endothelial growth factor (VEGF) around the sponge implants. Further, implanted tumor growth (sarcoma-180, Lewis lung carcinoma) was markedly suppressed in EP3(-/-), in which tumor-associated angiogenesis was also reduced. Immunohistochemical analysis revealed that major VEGF-expressing cells in the stroma were CD3/Mac-1 double-negative fibroblasts, and that VEGF-expression in the stroma was markedly reduced in EP3(-/-), compared with WT. Application of an EP3 receptor antagonist inhibited tumor growth and angiogenesis in WT, but not in EP3(-/-). These results demonstrate significance of host stromal PGE(2)-EP3 receptor signaling in tumor development and angiogenesis. An EP3 receptor antagonist may be a candidate of chemopreventive agents effective for malignant tumors.     

Re-engineering primary epithelial cells from rhesus monkey parotid glands for use in developing an artificial salivary gland

There is no satisfactory conventional treatment for patients who experience irreversible salivary gland damage after therapeutic radiation for head and neck cancer or because of Sj?gren's syndrome. Additionally, if most parenchyma is lost, these patients also are not candidates for evolving gene transfer strategies. To help such patients, several years ago we began to develop an artificial salivary gland. In the present study, we used a non-human primate tissue source, parotid glands from rhesus monkeys, to obtain potential autologous graft cells for development of a prototype device for in situ testing. Herein, we present 3 major findings. First, we show that primary cultures of rhesus parotid gland (RPG) cells are capable of attaining a polarized orientation, with Na(+)/K(+)-adenosine triphosphatase, zonula occludens-1, and claudin-1 distributed in specific domains appropriate for epithelial cells. Second, we show that RPG cells exhibit 2 essential epithelial functions required for graft cells in an artificial salivary gland device (i.e., an effective barrier to paracellular water flow and the generation of a moderate transepithelial electrical resistance). Third, we show that RPG cells can express functional water channels, capable of mediating directional fluid movement, after transduction by adenoviral and adeno-associated virus type 2 vectors. Together these results demonstrate that it is feasible to individually prepare RPG cells for eventual use in a prototype artificial salivary gland.