Sirt1 Activation by Post-ischemic Treatment With Lumbrokinase Protects Against Myocardial Ischemia-Reperfusion Injury.

Lumbrokinase is used as an oral supplement to support and maintain healthy cardiovascular function, and to treat cardiovascular diseases in clinical for more than 10 years. Up until now, the mechanism of the cardioprotective effects of post-ischemic treatment with lumbrokinase has remained unclear. We therefore investigated the signaling pathways involved in the amelioration of myocardial ischemia-reperfusion (I-R) injury in rats treated with lumbrokinase 20 min after myocardial ischemia. Compared to vehicle-treated rats, post-ischemic treatment with lumbrokinase was associated with significant reductions in myocardial I-R-induced arrhythmias and myocardial damage, and an improvement in cardiac function. Moreover, lumbrokinase significantly upregulated levels of silent information regulator 1 (Sirt1). In addition, lumbrokinase significantly increased manganese-dependent superoxide dismutase expression, decreased Cleaved-Caspase-3 expression, and induced deacetylation of FoxO1. On the other hand, lumbrokinase also significantly downregulated levels of succinate dehydrogenase, cytochrome c oxidase, nuclear factor kappa B (NF-κB) and elevated levels of microtubule-associated protein light chain 3. Notably, the cardioprotective effects of lumbrokinase were abolished by administration of the specific Sirt1 inhibitor EX527. These findings demonstrate that post-ischemic treatment with lumbrokinase attenuates myocardial I-R injury through the activation of Sirt1 signaling, and thus enhances autophagic flux and reduces I-R-induced oxidative damage, inflammation and apoptosis.

Differential impact of CX3CL1 on lung cancer prognosis in smokers and non-smokers.

CX3CL1 is a unique chemokine, expressed in both soluble and membrane bound forms, which mediates different biological activities. Recent studies have revealed the potential of CX3CL1 signaling pathway as a target for the treatment of inflammation and cancer. The correlation between expression of CX3CL1 and prognosis of patients varies among cancers. In this study, based on CX3CL1 immunohistochemistry in non-small cell lung cancer, CX3CL1 levels were positively associated with cancer stage (Pearson chi-square, P = 0.048) and lymph node status (P = 0.033). Interestingly, survival effects of CX3CL1 were only observed in patients with smoking history and adenocarcinoma (AD, log rank, P = 0.027), but not in patients with squamous cell carcinoma (SQ). The median survival time of patients with smoking history and low level CX3CL1 expressing AD was 1538 days, while that of patients with smoking history and high level CX3CL1 expressing AD was 396 days. Cox regression models showed adverse effects of high CX3CL1 levels only in AD patients with smoking history (hazard ratio = 3.01, p = 0.034), but not in AD patients without smoking history or in SQ patients with smoking history. The results of this study suggest that CX3CL1 plays different roles in lung tumorigenesis in smokers and non-smokers, and different CX3CL1-based therapeutic strategies are needed depending on patient smoking status and tumor type. Furthermore, high level of CX3CL1 expression enhances nodal metastasis by activating JNK & MMP2/MMP9 activity in lung cancer cells.

Identification of novel bovine RPE and retinal genes by subtractive hybridization.

PURPOSE: Understanding of the specialized function of the retinal pigment epithelium (RPE) can be aided by the identification and characterization of genes that are preferentially expressed in the RPE. With this aim, we undertook a systematic effort to identify and begin characterization of such genes. METHODS: A subtracted bovine RPE cDNA library was generated through subtractive hybridization using a single-stranded circular bovine RPE cDNA library as target and biotinylated mRNA from bovine heart and liver as alternate drivers. Approximately one thousand of the resulting subtracted cDNA clones were partially sequenced and analyzed, and a non-redundant set of one hundred of these cDNAs were examined for tissue expression pattern using a mini-Northern blot procedure and for identity by sequence analysis. RESULTS: The subtraction method successfully allowed the enrichment of cDNAs that are preferentially expressed in the RPE. Out of the analyzed clones, expression of forty-five clones was verifiable by Northern blotting. Of these, a significant proportion of cDNAs were preferentially expressed in the RPE. We observed that the expression of some subtracted cDNAs was restricted to the retina and no expression was detected in the RPE. These retinal clones were obtained in addition to RPE clones presumably because the initial RPE RNA population was contaminated with a small proportion of retinal RNA. Two thirds of the identified RPE and retinal cDNAs are likely to represent novel genes because they do not have homology to known genes in the databases. CONCLUSIONS: Genes that are specifically or predominantly expressed in the RPE/retina are likely to be important for retinal function. We have identified novel cDNAs from bovine RPE and retina by subtractive hybridization. These cDNAs can be used as starting material for the identification of corresponding human genes expressed in the RPE and retina. The human genes thus identified are likely to contain good candidate genes for retinal disease.