Nanocluster/metal-organic framework nanosheet-based confined ECL enhancement biosensor for the extracellular vesicle detection.

Gastric cancer (GC) was one of the most common cancers with high mortality. The detection of GC peritoneal metastasis had important significance. In this work, we have developed the novel electrochemiluminescence (ECL) biosensor to detect microRNA in GC extracellular vesicle (EV). Firstly, in situ growth of Cu nanocluster (Cu NC) on the metal-organic frameworks (MOFs) nanosheet was achieved successfully. Due to the confinement effect, Cu NCs in the porous structure of Zn MOF possessed the high quantum yield and good stability. Meanwhile, Zn MOF provided good electrochemical activity for the ECL reaction. Furthermore, the nanosized MOFs did not only act as sensing platform to load Cu NCs and link biomolecules, but also reduce steric hindrance effect for biomolecular recognition. Additionally, Au NPs/MXene and phospholipid layer were prepared and modified on the electrode, which can regulate electron transfer and improve the target recognition efficiency. The Cu NCs/Zn MOF nanosheet-based ECL sensor was employed to detect miRNA-421 from 1 fM to 1 nM with a detection limit of 0.5 fM. Finally, extracellular vesicles form clinic GC patient ascites were extracted and analyzed. The results showed that the constructed biosensor can be used for the GC peritoneal metastasis diagnosis.

Krill Oil Turns Off TGF-ß1 Profibrotic Signaling in the Prevention of Diabetic Nephropathy.

Diabetic nephropathy (DN), a severe microvascular complication of diabetes mellitus (DM), results in high mortality due to the lack of effective interventions. The current study investigated the preventive effect of krill oil (KO) on DN using a type 2 DM mouse model induced by streptozotocin and high-fat diet for 24 weeks. The diabetic mice developed albuminuria, mesangial matrix accumulation, glomerular hypertrophy, and fibrosis formation, with an increase in renal proinflammatory, oxidative and profibrotic gene expression. KO significantly prevented these effects but did not improve hyperglycemia and glucose intolerance. In high-glucose-treated mesangial cells (MCs), KO preferably modulated TGF-ß1 signaling as revealed by RNA-sequencing. In TGF-ß1-treated MCs, KO abolished SMAD2/3 phosphorylation and nuclear translocation and activated Smad7 gene expression. The action of KO on the SMADs was confirmed in the diabetic kidneys. Therefore, KO may prevent DN predominantly by suppressing the TGF-ß1 signaling pathway.

Blood HDAC4 Variation Links With Disease Activity and Response to Tumor Necrosis Factor Inhibitor and Regulates CD4+ T Cell Differentiation in Ankylosing Spondylitis.

Purpose: Histone deacetylase 4 (HDAC4) regulates the progression of autoimmune diseases. This study aimed to further investigate the correlation between HDAC4 and Th cells, inflammation, disease activity, and treatment response in patients with ankylosing spondylitis (AS). Methods: A total of 132 active patients with AS were enrolled, of whom 54 patients received TNF inhibitor (TNFi) and 78 patients received NSAID. Serum HDAC4 was measured by ELISA in patients with AS before treatment (W0) and at week (W)4, W8, and W12 after treatment. Meanwhile, serum HDAC4 was detected in 30 patients with osteoarthritis and in 30 healthy controls (HCs) by ELISA. Besides, naïve CD4+ T cells from patients with AS were isolated, followed by modulation of HDAC4 and then polarization toward Th1, Th2, and Th17. Results: Histone deacetylase 4 was reduced in patients with AS compared with HCs and patients with osteoarthritis (both P < 0.01). In patients with AS, HDAC4 was negatively correlated with TNF (P < 0.001), IL-1ß (P = 0.003), Th17 proportion (P = 0.008), C-reactive protein (P < 0.001), and ASDAS (P = 0.038), but not with IL-6, Th1 proportion, or other characteristics. Meanwhile, HDAC4 increased from W0 to W12 (P < 0.001); HDAC4 at W8 (P = 0.014) and W12 (P = 0.006) was raised in ASAS40-response patients than ASAS40-non-response patients; further subgroup analysis showed that HDAC4 at W12 was higher in ASAS40-response patients than ASAS40-non-response patients (P = 0.016) in the TNFi-treated group, but not in the NSAID-treated group. In addition, HDAC4 negatively regulated the polarization of naïve CD4+ T cells toward Th17 (P < 0.01), but not Th1 or Th2. Conclusion: Histone deacetylase 4 is associated with lower inflammation, and the disease activity negatively regulates Th17 polarization, whose increment after treatment reflects favorable outcomes in patients with AS.

The common risk factors for progression and mortality in COVID-19 patients: a meta-analysis.

Coronavirus disease 2019 (COVID-19), defined by the World Health Organization (WHO), has affected more than 50 million patients worldwide and caused a global public health emergency. Therefore, there is a recognized need to identify risk factors for COVID-19 severity and mortality. A systematic search of electronic databases (PubMed, Embase and Cochrane Library) for studies published before September 29, 2020, was performed. Studies that investigated risk factors for progression and mortality in COVID-19 patients were included. A total 344,431 participants from 34 studies were included in this meta-analysis. Regarding comorbidities, cerebrovascular disease (CVD), chronic kidney disease (CKD), coronary heart disease (CHD), and malignancy were associated with an increased risk of progression and mortality in COVID-19 patients. Regarding clinical manifestations, sputum production was associated with a dramatically increased risk of progression and mortality. Hemoptysis was a risk factor for death in COVID-19 patients. In laboratory examinations, increased neutrophil count, decreased lymphocyte count, decreased platelet count, increased C-reactive protein (CRP), coinfection with bacteria or fungi, increased alanine aminotransferase (ALT) and creatine kinase (CK), increased N-terminal pronatriuretic peptide (NT-proBNP), and bilateral pneumonia in CT/X-ray were significantly more frequent in the severe group compared with the non-severe group. Moreover, the proportion of patients with increased CRP and total bilirubin (TBIL) was also significantly higher in the deceased group than in the survival group. CVD, CKD, sputum production, increased neutrophil count, decreased lymphocyte count, decreased platelet count, increased CRP, coinfection with bacteria or fungi, increased ALT and CK, increased NT-proBNP, and bilateral pneumonia in CT/X-ray were associated with an increased risk of progression in COVID-19 patients. Moreover, the proportion of patients with increased sputum production, hemoptysis, CRP and TBIL was also significantly higher in the deceased group.

Establishment of a novel risk score model by comprehensively analyzing the immunogen database of bladder cancer to indicate clinical significance and predict prognosis.

BACKGROUND: Bladder cancer (BCa) has the highest incidence of aggressive malignant tumors in the urogenital system and is the ninth most common cancer worldwide. Immune function-related genes (IFRGs), which are plentiful in immune cells and the immune microenvironment (IME), have the potential to assess prognosis and predict the efficacy of immunotherapy. A complete and significant immunogenomic analysis based on abundant BCa genetic samples from The Cancer Genome Atlas (TCGA) will provide insight into the field. RESULTS: A total of 57 differentially expressed IFRGs were significantly associated with the clinical outcomes of patients with BCa. Functional enrichment analysis showed that these genes actively participated in the KEGG pathway of human cytomegalovirus infection. Based on the IFRGs (CALR, MMP9, PAEP, RBP7, STAT1, CACYBP, ANHAK, RAC3, SLIT2, EDNRA, IGF1, NAMPT, NTF3, PPY, ADRB2 and SH3BP2), the risk scores were calculated to predict survival and reveal the relationships with age, sex, grade, staging, T-stage, N-stage, and M-stage. Interestingly, IFRG-based risk scores (IRRSs) reflected the infiltration of several types of immune cells. The expression of CACYBP was more significant in grade 3, T3 and T4 stages than in earlier grades and T-stages. CONCLUSION: Our results highlighted some sIFRGs with remarkable clinical relevance, showed the driving factors of the immune repertoire, and illustrated the significance of IFRG-based individual immune features in the identification, monitoring, and prognosis of patients with BCa. METHODS: Based on the TCGA dataset, we integrated the expression profiles of IFRGs and overall survival (OS) in 430 patients with BCa. Differentially expressed IFRGs and survival-related IFRGs (sIFRGs) were highlighted by calculating the difference algorithm and COX regression analysis in patients with BCa. Based on computational biology, the potential molecular mechanisms and characteristics of these IFRGs were also explored. Using multivariate Cox analysis, new risk scores based on immune-related genes were developed. The expression of CACYBP was verified by qPCR, western blot and immunohistochemistry. The relations between CACYBP and clinical features were proven by immunohistochemistry.

The Role of Akt2 in the Protective Effect of Fenofibrate against Diabetic Nephropathy.

Fenofibrate (FF) protects against diabetic nephropathy (DN) in type 1 diabetic (T1D) mice by upregulating the expression of fibroblast growth factor 21 (FGF21), leading to the activation of the Akt-mediated Nrf2 antioxidant pathways. Here, we examined which isoforms of Akt contribute to FF activation of FGF21-mediated renal protection by examining the phosphorylation and expression of three isoforms, Akt1, Akt2, and Akt3. T1D induced by a single intraperitoneal dose of streptozotocin (STZ) resulted in reduced phosphorylation of one isoform, Akt2, but FF treatment increased renal Akt2 phosphorylation in these and normal mice, suggesting a potential and specific role for renal Akt2 in FF protection against T1D. This was further confirmed using in vitro cultured HK-2 human kidney tubule cells exposed to high glucose (HG) with siRNA silencing of the Akt2 gene and STZ-induced diabetic Akt2-knockout mice with and without 3-month FF treatment. In normal HK-2 cells exposed to HG for 24 hours, FF completely prevented cell death, reduced total Akt expression and glycogen synthase kinase (GSK)-3ß phosphorylation, increased nuclear accumulation of Fyn, and reduced nuclear Nrf2 levels. These positive effects of FF were partially abolished by silencing Akt2 expression. Similarly, FF abolished T1D-induced renal oxidative stress, inflammation, and renal dysfunction in wild-type mice, but was only partially effective in Akt2-KO mice. Furthermore, FF treatment stimulated phosphorylation of AMPKα, an important lipid metabolism mediator, which in parallel with Akt2 plays an important role in FF protection against HG-induced HK-2 cells oxidative stress and damage. These results suggest that FF protects against DN through FGF21 to activate both Akt2/GSK-3ß/Fyn/Nrf2 antioxidants and the AMPK pathway. Therefore, FF could be repurposed for the prevention of DN in T1D patients.

MicroRNA-544 attenuates diabetic renal injury via suppressing glomerulosclerosis and inflammation by targeting FASN.

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. Accumulating evidence shows that microRNAs play important roles in diabetic kidney. However, the potential role of MicroRNA-544 (miR-544) in DN remains unclear. In this study, we explored the role of miR-544 on inflammation and fibrosis in diabetic kidney using db/db mice. Renal expression of miR-544 was decreased in mice, companied by increased the expression of FASN. The dual luciferase assay confirmed FASN as a direct target of miR-544. Over-expression of miR-544 significantly ameliorated renal injury, mesangial matrix and renal fibrosis. In addition, over-expression of miR-544 significantly attenuated inflammatory cells infiltration and IL-1, IL-6, TNF- and iNOS production in DN. Furthermore, miR-544 over-expression inhibited the activation of NF-kB signal pathway in DN. In conclusion, our finding demonstrated that miR-544 attenuates diabetic renal injury via suppressing glomerulosclerosis and inflammation by targeting FASN, suggesting that miR-544 might have therapeutic potential for the treatment of DN.

Prophylactic atorvastatin prior to intra-arterial administration of iodinated contrast media for prevention of contrast-induced acute kidney injury: A meta-analysis of randomized trial data
.

BACKGROUND: The efficacy of high-dose atorvastatin pretreatment in reducing the incidence of contrast-induced nephropathy in patients undergoing coronary angiography (CAG) or percutaneous coronary intervention (PCI) has been examined in some randomized studies. However, the results across the trials remain controversial. OBJECTIVE: This study sought to perform a meta-analysis to evaluate the effect of high-dose atorvastatin in the prevention of contrast-induced nephropathy (CIN) while undergoing CAG or PCI. MATERIALS AND METHODS: Comprehensive literature searches for randomized controlled trials (RCTs) comparing high-dose atorvastatin vs. low-dose statin or placebo pretreatment for prevention of contrast-induced acute kidney injury in patients undergoing CAG were performed using PubMed, Embase, and the Cochrane library updated to June 2017. The primary outcome was the incidence of CIN. RESULTS: A total of 11 RCTs were included in this analysis. The high-dose atorvastatin treatment can significantly reduce the incidence of CIN (OR 0.46, 95% CI 0.35 - 0.62, p < 0.00001). The benefit was consistent in comparison with the low-dose group (OR 0.41, 95% CI 0.25 - 0.66, p = 0.0003) and the placebo group (OR 0.50, 95% CI 0.26 - 0.98, p = 0.04). CONCLUSION: Our study demonstrates that high-dose statin pretreatment shows a benefit specifically in reducing the incidence of contrast-induced acute kidney injury in patients undergoing CAG, especially compared with low-dose statin pretreatment.

Overexpression of the long non-coding RNA Oprm1 alleviates apoptosis from cerebral ischemia-reperfusion injury through the Oprm1/miR-155/GATA3 axis.

Numerous differentially expressed long non-coding RNAs (lncRNAs) have been identified in cerebral ischemia-reperfusion (I/R) injury using RNA-Seq analysis. However, little is known about whether and how lncRNAs are involved in cerebral I/R injury. In this study, we investigated the function of the lncRNA Oprm1 in cerebral I/R injury and explored the underlying mechanism. An oxygen-glucose deprivation model in N2a cells was utilized to mimic cerebral I/R injury in vitro. Trypan blue staining, terminal deoxytransferase-mediated dUTP-biotin nick end labelling and caspase-3 were measured to evaluate apoptosis. Middle cerebral artery occlusion was performed in mice to evaluate the function of lncRNA Oprm1 in vivo. Real-time PCR and western blotting were used to measure the expression levels of lncRNA Opmr1, caspase-3, miR-155, GATA binding protein 3 (GATA3) and nuclear factor (NF)-κB. lncRNA Oprm1 was mainly located in the cytoplasm. Overexpression of lncRNA Oprm1 alleviated the apoptosis induced by oxygen-glucose deprivation and significantly reduced cleaved caspase-3 levels. Infarct size was distinctly decreased in the lncRNA Oprm1-overexpression group. The neurological score was also improved. Our findings showed that the lncRNA Oprm1/miR-155/GATA3 axis plays an important role in cerebral I/R injury. lncRNA Oprm1 may attenuate cerebral injury through the NF-κB pathway. lncRNA Oprm1 may serve as a potential target for new therapeutic interventions in patients with ischemic stroke.

P53/NRF2 mediates SIRT1's protective effect on diabetic nephropathy.

Diabetic nephropathy (DN) is the leading cause of end stage renal disease, posing a severe threat to public health. Previous studies reported the protective role of sirtuin 1 (SIRT1) in DN, encouraging the investigation of more potent and specific SIRT1 activators. SRT2104 is a novel, first-in-class, highly selective small-molecule activator of SIRT1, with its effect and mechanism unknown on DN. To this end, streptozotocin-induced C57BL/6 wild-type (WT) diabetic mice were treated with SRT2104, for 24 weeks. To determine whether SRT2104 acted through inhibition of P53 - a substrate of SIRT1, the P53 activator nutlin3a was administered to the WT diabetic mice in the presence of SRT2104. In order to test whether nuclear factor erythroid 2-related factor 2 (NRF2) - the master of cellular antioxidants - mediated SIRT1 and P53's actions, WT and Nrf2 gene knockout (KO) diabetic mice were treated with SRT2104 or the P53 inhibitor pifithrin-α (PFT-α). In the WT mice, SRT2104 enhanced renal SIRT1 expression and activity, deacetylated P53, and activated NRF2 antioxidant signaling, providing remarkable protection against the DM-induced renal oxidative stress, inflammation, fibrosis, glomerular remodeling and albuminuria. These effects were completely abolished in the presence of nutlin3a. Deletion of the Nrf2 gene completely abrogated the efficacies of SRT2104 and PFT-α in elevating antioxidants and ameliorating DN, despite their abilities to activate SIRT1 and inhibit P53 in the Nrf2 KO mice. The present study reports the beneficial effects of SRT2104 on DN, uncovering a SIRT1/P53/NRF2 pathway that modulates the pathogenesis of DN.

MicroRNA-224 enhances the osteoblastic differentiation of hMSCs via Rac1.

Osteogenesis is the differentiation of mesenchymal stem cells (MSCs) into osteoblasts. MicroRNAs (miRNAs) are short noncoding RNAs that target specific genes to mediate translational activities. In this study, we investigated how miR-224 regulates the osteoblastic differentiation of human MSCs (hMSCs) as well as the underlying mechanism. The results revealed the upregulation of miR-224 during hMSC differentiation. In vitro experiments showed that the downregulation of miR-224 suppressed the differentiation of hMSCs into osteoblasts. However, upregulation of miR-224 was concomitant with increased expression of relevant genes and augmented activity of alkaline phosphatase. Furthermore, the results indicated that Rac1 acted as the bona fide target of miR-224 and that Rac1 depletion promoted osteogenic differentiation in miR-224-silenced hMSCs. In addition, we found that both JAK/STAT3 and Wnt/ß-catenin pathways were repressed by Rac1 depletion using quantitative reverse transcription polymerase chain reaction (qRT-PCR), western blotting, and immunofluorescence. Our data indicate a novel molecular mechanism in relation to hMSCs differentiation into osteoblasts, which may facilitate bone anabolism via miR-224. SIGNIFICANCE OF THE STUDY: In this study, we mainly explored the effects of miR-224 on hMSCs differentiation into osteoblasts. We find that induced miR-224 expression in hMSCs is considered closely associated with specific osteogenesis-related genes, alkaline phosphatase activity, and matrix mineralization, indicating that miR-224 may serve as a promising biomarker for osteogenic differentiation. Our data indicate a novel molecular mechanism in relation to hMSCs differentiation into osteoblasts, which may facilitate bone anabolism via miR-224.

Inhibition of P53/miR-34a improves diabetic endothelial dysfunction via activation of SIRT1.

Endothelial dysfunction contributes to diabetic macrovascular complications, resulting in high mortality. Recent findings demonstrate a pathogenic role of P53 in endothelial dysfunction, encouraging the investigation of the effect of P53 inhibition on diabetic endothelial dysfunction. Thus, high glucose (HG)-treated endothelial cells (ECs) were subjected to pifithrin-α (PFT-α)-a specific inhibitor of P53, or P53-small interfering RNA (siRNA), both of which attenuated the HG-induced endothelial inflammation and oxidative stress. Moreover, inhibition of P53 by PFT-α or P53-siRNA prohibited P53 acetylation, decreased microRNA-34a (miR-34a) level, leading to a dramatic increase in sirtuin 1 (SIRT1) protein level. Interestingly, the miR-34a inhibitor (miR-34a-I) and PFT-α increased SIRT1 protein level and alleviated the HG-induced endothelial inflammation and oxidative stress to a similar extent; however, these effects of PFT-α were completely abrogated by the miR-34a mimic. In addition, SIRT1 inhibition by EX-527 or Sirt1-siRNA completely abolished miR-34a-I's protection against HG-induced endothelial inflammation and oxidative stress. Furthermore, in the aortas of streptozotocin-induced diabetic mice, both PFT-α and miR-34a-I rescued the inflammation, oxidative stress and endothelial dysfunction caused by hyperglycaemia. Hence, the present study has uncovered a P53/miR-34a/SIRT1 pathway that leads to endothelial dysfunction, suggesting that P53/miR-34a inhibition could be a viable strategy in the management of diabetic macrovascular diseases.

Knockdown of TLR4 attenuates high glucose-induced podocyte injury via the NALP3/ASC/Caspase-1 signaling pathway.

Diabetic nephropathy (DN) is one of the most common syndromes of the diabetic mellitus, and is the leading cause of end-stage renal disease. TLR4 (Toll-like receptor 4) has been shown to be implicated in the progression of DN. However, the role of TLR4 in DN and its underlying mechanism remain elusive. In this study, we found that high glucose (HG) activated nucleotide binding and oligomerization domain-like receptor family pyrin domain-containing 3 (NALP3) inflammasome, as shown by elevated NALP3, apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC) and cleaved caspase-1 protein levels, and increased caspase-1 activity in mouse podocytes in vitro. Simultaneously, HG decreased the mRNA and protein expression of Wilm's tumor-1 and synaptopodin, and increased the mRNA and protein expression levels of desmin in podocytes, in a dose-dependent manner. Administration of HG increased the number of TUNEL-positive cells, inhibited the viability of podocytes, elevated the intracellular level of ROS, and increased the levels of IL-1ß, IL-18, TNF-α and TGF-ß1. Moreover, the effects of HG were effectively blocked by repression of NALP3 or ASC. Furthermore, TLR4 was upregulated in HG-stimulated podocytes. TLR4 knockdown inhibited the activation of NALP3 inflammasome in HG-treated podocytes, as indicated by the decrease in NALP3, ASC and cleaved caspase-1 protein levels and the reduction in caspase-1 activity. Additionally, knockdown of TLR4 attenuated the HG-induced increase of cell apoptosis and reduction of cell viability in podocytes. TLR4 knockdown reduced the intracellular level of ROS in conjunction with reduced IL-1ß, IL-18, TNF-α and TGF-ß1 levels in podocytes in the presence of HG. In conclusion, knockdown of TLR4 attenuates HG-induced podocyte injury via the NALP3/ASC/Caspase-1 signaling pathway.

Endothelial nitric oxide synthase gene polymorphisms and risk of erectile dysfunction: An updated meta-analysis of genetic association studies.

PURPOSE: Endothelial nitric oxide synthase (eNOS) polymorphisms have been implicated as risk factors for erectile dysfunction (ED), but the results of genetic association studies are inconclusive. We performed a meta-analysis of published studies investigating the association between ED and three eNOS polymorphisms, intron 4 VNTR, G894T and T786C in humans. METHODS: The PubMed, Web of Science, CNKI and Google Scholar databases were searched for relevant studies published up to November 2017. Association studies with case-control design were included. For each study with genotype information we calculated odds ratios (OR) and 95% confidence intervals (CI). RESULTS: The search identified 13 eligible studies. The G894T and T786C polymorphisms showed a significant association with ED risk in Caucasians (GT + TT versus GG for G894T: OR = 2.13, 95% CI = 1.08-4.19; CC versus CT + TT for T786C: OR = 3.29, 95% CI = 2.30-4.72) and Asians (GT + TT versus GG for G894T: OR = 2.08, 95% CI = 1.53-2.84; CC + CT versus TT for T786C: OR = 3.13, 95% CI = 1.35-7.25). In addition, the intron 4 VNTR polymorphism was associated with ED risk only among Caucasian subjects (aa versus bb + ab: OR = 2.38, 95% CI = 1.15-4.93). We found no evidence of publication bias. The robustness of overall analyses was ensured in sensitivity analyses excluding studies deviating from Hardy-Weinberg equilibrium. CONCLUSION: Our findings suggest that common genetic polymorphisms in the eNOS gene contribute to risk of ED, presumably by effects on eNOS activity and NO availability.

Efficacy of atorvastatin on the prevention of contrast-induced acute kidney injury: a meta-analysis.

BACKGROUND: Results of studies on the efficacy of atorvastatin pretreatment on reducing the prevalence of contrast-induced acute kidney injury (CIAKI) in patients undergoing coronary angiography (CAG) or percutaneous coronary intervention (PCI) have been controversial. OBJECTIVE: We undertook a meta-analysis to evaluate the efficacy of atorvastatin on contrast-induced nephropathy (CIN) after CAG or PCI. MATERIALS AND METHODS: We undertook a systematic search of electronic databases (PubMed, Embase, and the Cochrane Library) up to June 2017. A meta-analysis was carried out including randomized controlled trials (RCTs) that compared atorvastatin pretreatment with pretreatment with a low-dose statin or placebo for CIAKI prevention in patients undergoing CAG. The main endpoint was CIN prevalence. RESULTS: Nine RCTs were included in our meta-analysis. Atorvastatin pretreatment reduced the prevalence of CIN significantly (odds ratio [OR] 0.46; 95% confidence interval [95% CI] 0.27-0.79; p=0.004). The benefit of high-dose atorvastatin pretreatment was consistent when compared with the control group (OR 0.45; 95% CI 0.21-0.95; p=0.04). CONCLUSION: At high doses, atorvastatin pretreatment was associated with a significant reduction in the prevalence of CIAKI in patients undergoing CAG. Pretreatment with high-dose atorvastatin could be employed to prevent CIAKI.

Identification of key genes for diabetic kidney disease using biological informatics methods.

Diabetic kidney disease (DKD) is a common complication of diabetes, which is characterized by albuminuria, impaired glomerular filtration rate or a combination of the two. The aim of the present study was to identify the potential key genes involved in DKD progression and to subsequently investigate the underlying mechanism involved in DKD development. The array data of GSE30528 including 9 DKD and 13 control samples was downloaded from the Gene Expression Omnibus database. The differentially expressed genes (DEGs) in DKD glomerular and tubular kidney biopsy tissues were compared with normal tissues, and were analyzed using the limma package. Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed for DEGs using the GO Function software in Bioconductor. The protein­protein interaction (PPI) network was then constructed using Cytoscape software. A total of 426 genes (115 up­ and 311 downregulated) were differentially expressed between the DKD and normal tissue samples. The PPI network was constructed with 184 nodes and 335 edges. Vascular endothelial growth factor A (VEGFA), α­actinin­4 (ACTN4), proto­oncogene, Src family tyrosine kinase (FYN), collagen, type 1, α2 (COL1A2) and insulin­like growth factor 1 (IGF1) were hub proteins. Major histocompatibility complex, class II, DP α1 (HLA­DPA1) was the common gene enriched in the rheumatoid arthritis and systemic lupus erythematosus pathways, and the immune response was a GO term enriched in module A. VEGFA, ACTN4, FYN, COL1A2, IGF1 and HLA­DPA1 may be potential key genes associated with the progression of DKD, and immune mechanisms may serve a part in DKD development.

Smoking as a risk factor for diabetic nephropathy: a meta-analysis.

BACKGROUND: Previous studies have investigated the connection between diabetic nephropathy and smoking, and reported widely varying rates. This study aimed to systematically analyze the impact of smoking on diabetic nephropathy. METHODS: We searched the PubMed and EMBASE electronic databases to identify relevant English-language studies published up to March 2016. Eligible studies were selected using inclusion and exclusion criteria. Data for each study were extracted independently by two authors. The homogeneity of the effect size across the studies was tested. Odds ratio (OR) was calculated by using the random-effect model. Sensitivity analysis was performed to reduce heterogeneity, and publication biases were examined. RESULTS: A total of 21 eligible studies were selected and pooled analyzed. No significant differences in demographic characteristics were found between patients with diabetic nephropathy and those with non-diabetic nephropathy. Significant heterogeneity across studies was found except those of diabetes mellitus controls. The aggregate OR of smoking in the patients with diabetic nephropathy in comparison with those with non-diabetic nephropathy was 1.70 (95% confidence interval 1.48-1.95). No evidence of publication bias was found. CONCLUSION: Our findings indicate that smoking is a significant risk factor for diabetic nephropathy in diabetic patients.

p16ink4a Expression Is Increased through 12-Lipoxygenase in High Glucose-Stimulated Glomerular Mesangial Cells and Type 2 Diabetic Glomeruli.

BACKGROUND/AIMS: Arachidonic acid-metabolizing enzyme, 12-lipoxygenase (12-LO), is involved in the glomerular hypertrophy of diabetic nephropathy (DN), in which cyclin-dependent kinase inhibitors (CKIs) play important roles. However, it is unclear whether 12-LO regulates the expression of the CKI p16(ink4a) in DN. METHODS: Primary glomerular mesangial cells (MCs) and glomeruli isolated from rats were used in this study. The rats were fed a high-fat diet and given low-dose streptozotocin to induce type 2 diabetes. The 12-LO product, 12(S)-hydroxyeicosatetraenoic acid (12(S)-HETE), was infused through an osmotic minipump. Enzyme-linked immunosorbent assay, Western blot, and morphometric analyses were performed. RESULTS: High glucose (HG) increased the p16(ink4a) protein expression in MCs, but this increase was prevented by the 12-LO inhibitor, cinnamyl-3,​4-dihydroxy-α-cynanocinnamate (CDC). The levels of p-p38MAPK and p16(ink4a) in MCs were significantly elevated after the 12(S)-HETE treatment, whereas the p38MAPK inhibitor SB203580 prevented these increases. Compared with levels in control MCs, marked increases in p38MAPK activation and p16(ink4a) expression were observed in MCs plated on collagen IV, while the CDC treatment prevented these changes. Subcutaneous injection of CDC did not affect glucose levels, but completely attenuated the diabetes-related increases in the 12(S)-HETE content, p16(ink4a) expression, p-p38MAPK levels, glomerular volume, and the kidney/body weight ratio. Compared with levels in controls, p16(ink4a) and p-p38MAPK in the glomeruli derived from 12(S)-HETE-treated rats were significantly higher. CONCLUSIONS: 12-LO-p38MAPK mediates the upregulation of p16(ink4a) in HG-stimulated MCs and type 2-diabetic glomeruli, and new therapies aimed at 12-LO inhibition may prove beneficial in ameliorating diabetes-induced glomerular hypertrophy.