Cardiac-specific PFKFB3 overexpression prevents diabetic cardiomyopathy via enhancing OPA1 stabilization mediated by K6-linked ubiquitination.

Diabetic cardiomyopathy (DCM) is a prevalent complication of type 2 diabetes (T2D). 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) is a glycolysis regulator. However, the potential effects of PFKFB3 in the DCM remain unclear. In comparison to db/m mice, PFKFB3 levels decreased in the hearts of db/db mice. Cardiac-specific PFKFB3 overexpression inhibited myocardial oxidative stress and cardiomyocyte apoptosis, suppressed mitochondrial fragmentation, and partly restored mitochondrial function in db/db mice. Moreover, PFKFB3 overexpression stimulated glycolysis. Interestingly, based on the inhibition of glycolysis, PFKFB3 overexpression still suppressed oxidative stress and apoptosis of cardiomyocytes in vitro, which indicated that PFKFB3 overexpression could alleviate DCM independent of glycolysis. Using mass spectrometry combined with co-immunoprecipitation, we identified optic atrophy 1 (OPA1) interacting with PFKFB3. In db/db mice, the knockdown of OPA1 receded the effects of PFKFB3 overexpression in alleviating cardiac remodeling and dysfunction. Mechanistically, PFKFB3 stabilized OPA1 expression by promoting E3 ligase NEDD4L-mediated atypical K6-linked polyubiquitination and thus prevented the degradation of OPA1 by the proteasomal pathway. Our study indicates that PFKFB3/OPA1 could be potential therapeutic targets for DCM.

11,12-EET suppressed LPS induced TF expression and thrombus formation by accelerating mRNA degradation rate via strengthening PI3K-Akt signaling pathway and inhibiting p38-TTP pathway.

Epoxyeicosatrienoic acids (EETs), which are synthesized from arachidonic acid by cytochrome P450 epoxygenases, function primarily as autocrine and paracrine effectors in the cardiovascular system. So far, most research has focused on the vasodilatory, anti-inflammatory, anti-apoptotic and mitogenic properties of EETs in the systemic circulation. However, whether EETs could suppress tissue factor (TF) expression and prevent thrombus formation remains unknown. Here we utilized in vivo and in vitro models to investigate the effects and underlying mechanisms of exogenously EETs on LPS induced TF expression and inferior vein cava ligation induced thrombosis. We observed that the thrombus formation rate and the size of the thrombus were greatly reduced in 11,12-EET treated mice，accompanied by decreased TF and inflammatory cytokines expression. Further in vitro studies showed that by enhancing p38 MAPK activation and subsequent tristetraprolin (TTP) phosphorylation, LPS strengthened the stability of TF mRNA and induced increased TF expression. However, by strengthening PI3K-dependent Akt phosphorylation, which acted as a negative regulator of p38-TTP signaling pathway，11,12-EET reduced LPS-induced TF expression in monocytes. In addition, 11,12-EET inhibited LPS-induced NF-κB nuclear translocation by activating the PI3K/Akt pathway. Further study indicated that the inhibitory effect of 11,12-EET on TF expression was mediated by antagonizing LPS-induced activation of thromboxane prostanoid receptor. In conclusion, our study demonstrated that 11,12-EET prevented thrombosis by reducing TF expression and targeting the CYP2J2 epoxygenase pathway may represent a novel approach to mitigate thrombosis related diseases.

Inulin-type fructans change the gut microbiota and prevent the development of diabetic nephropathy.

Diabetic nephropathy (DN) is the most common cause of end-stage renal disease, and few treatment options that prevent the progressive loss of renal function are available. Studies have shown that dietary fiber intake improves kidney diseases and metabolism-related diseases, most likely through short-chain fatty acids (SCFAs). The present study aimed to examine the protective effects of inulin-type fructans (ITFs) on DN through 16 S rRNA gene sequencing, gas chromatographymass spectrometry (GCMS) analysis and fecal microbiota transplantation (FMT). The results showed that ITFs supplementation protected against kidney damage in db/db mice and regulated the composition of the gut microbiota. Antibiotic treatment and FMT experiments further demonstrated a key role of the gut microbiota in mediating the beneficial effects of ITFs. The ITFs treatment-induced changes in the gut microbiota led to an enrichment of SCFA-producing bacteria, especially the genera Akkermansia and Candidatus Saccharimonas, which increased the fecal and serum acetate concentrations. Subsequently, acetate supplementation improved glomerular damage and renal fibrosis by attenuating mitochondrial dysfunction and reducing toxic glucose metabolite levels. In conclusion, ITFs play a renoprotective role by modulating the gut microbiota and increasing acetate production. Furthermore, acetate mediates renal protection by regulating glucose metabolism, decreasing glycotoxic product levels and improving mitochondrial function.

Soluble epoxide hydrolase deletion attenuated nicotine-induced arterial stiffness via limiting the loss of SIRT1.

Arterial stiffness, a consequence of smoking, is an underlying risk factor of cardiovascular diseases. Epoxyeicosatrienoic acids (EETs), hydrolyzed by soluble epoxide hydrolase (sEH), have beneficial effects against vascular dysfunction. However, the role of sEH knockout in nicotine-induced arterial stiffness was not characterized. We hypothesized that sEH knockout could prevent nicotine-induced arterial stiffness. In the present study, Ephx2 (the gene encodes sEH enzyme) null (Ephx2-/-) mice and wild-type (WT) littermate mice were infused with or without nicotine and administered with or without nicotinamide [NAM, sirtuin-1 (SIRT1) inhibitor] simultaneously for 4 wk. Nicotine treatment increased sEH expression and activity in the aortas of WT mice. Nicotine infusion significantly induced vascular remodeling, arterial stiffness, and SIRT1 deactivation in WT mice, which was attenuated in Ephx2 knockout mice (Ephx2-/- mice) without NAM treatment. However, the arterial protective effects were gone in Ephx2-/- mice with NAM treatment. In vitro, 11,12-EET treatment attenuated nicotine-induced matrix metalloproteinase 2 (MMP2) upregulation via SIRT1-mediated yes-associated protein (YAP) deacetylation. In conclusion, sEH knockout attenuated nicotine-induced arterial stiffness and vascular remodeling via SIRT1-induced YAP deacetylation.NEW & NOTEWORTHY We presently show that sEH knockout repressed nicotine-induced arterial stiffness and extracellular matrix remodeling via SIRT1-induced YAP deacetylation, which highlights that sEH is a potential therapeutic target in smoking-induced arterial stiffness and vascular remodeling.

Targeted resequencing showing novel common and rare genetic variants increases the risk of asthma in the Chinese Han population.

BACKGROUND: Although studies have identified hundreds of genetic variants associated with asthma risk, a large fraction of heritability remains unexplained, especially in Chinese individuals. METHODS: To identify genetic risk factors for asthma in a Han Chinese population, 211 asthma-related genes were first selected based on database searches. The genes were then sequenced for subjects in a Discovery Cohort (284 asthma patients and 205 older healthy controls) using targeted next-generation sequencing. Bioinformatics analysis and statistical association analyses were performed to reveal the associations between rare/common variants and asthma, respectively. The identified common risk variants underwent a validation analysis using a Replication Cohort (664 patients and 650 controls). RESULTS: First, we identified 18 potentially functional rare loss-of-function (LOF) variants in 21/284 (7.4%) of the asthma cases. Second, using burden tests, we found that the asthma group had nominally significant (p < 0.05) burdens of rare nonsynonymous variants in 10 genes. Third, 23 common single-nucleotide polymorphisms were associated with the risk of asthma, 7/23 (30.4%) and 9/23 (39.1%) of which were modestly significant (p < 9.1 × 10-4 ) in the Replication Cohort and Combined Cohort, respectively. According to our cumulative risk model involving the modestly associated alleles, middle- and high-risk subjects had a 2.0-fold (95% CI: 1.621-2.423, p = 2.624 × 10-11 ) and 6.0-fold (95% CI: 3.623-10.156, p = 7.086 × 10-12 ) increased risk of asthma, respectively, compared with low-risk subjects. CONCLUSION: This study revealed novel rare and common genetic risk factors for asthma, and provided a cumulative risk model for asthma risk prediction and stratification in Han Chinese individuals.

Inhibition of soluble epoxide hydrolase alleviates insulin resistance and hypertension via downregulation of SGLT2 in the mouse kidney.

The epoxyeicosatrienoic acid (EET) exerts beneficial effects on insulin resistance and/or hypertension. EETs could be readily converted to less biological active diols by soluble epoxide hydrolase (sEH). However, whether sEH inhibition can ameliorate the comorbidities of insulin resistance and hypertension and the underlying mechanisms of this relationship are unclear. In this study, C57BL/6 mice were rendered hypertensive and insulin resistant through a high-fat and high-salt (HF-HS) diet. The sEH inhibitor, 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU), was used to treat mice (1 mg/kg/day) for 8 weeks, followed by analysis of metabolic parameters. The expression of sEH and the sodium-glucose cotransporter 2 (SGLT2) was markedly upregulated in the kidneys of mice fed an HF-HS diet. We found that TPPU administration increased kidney EET levels, improved insulin resistance, and reduced hypertension. Furthermore, TPPU treatment prevented upregulation of SGLT2 and the associated increased urine volume and the excretion of urine glucose and urine sodium. Importantly, TPPU alleviated renal inflammation. In vitro, human renal proximal tubule epithelial cells (HK-2 cells) were used to further investigate the underlying mechanism. We observed that 14,15-EET or sEH knockdown or inhibition prevented the upregulation of SGLT2 upon treatment with palmitic acid or NaCl by inhibiting the inhibitory kappa B kinase α/ß/NF-κB signaling pathway. In conclusion, sEH inhibition by TPPU alleviated insulin resistance and hypertension induced by an HF-HS diet in mice. The increased urine excretion of glucose and sodium was mediated by decreased renal SGLT2 expression because of inactivation of the inhibitory kappa B kinase α/ß/NF-κB-induced inflammatory response.

The potential association between common comorbidities and severity and mortality of coronavirus disease 2019: A pooled analysis.

BACKGROUD: The association between underlying comorbidities and cardiac injury and the prognosis in coronavirus disease 2019 (COVID-19) patients was assessed in this study. HYPOTHESIS: The underlying comorbidities and cardiac injury may be associated with the prognosis in COVID-19 patients. METHODS: A systematic search was conducted in PubMed, EMBASE, Web of science, and The Cochrane library from December 2019 to July 2020. The odds ratio (OR) and 95% confidence intervals (95% CI) were used to estimate the probability of comorbidities and cardiac injury in COVID-19 patients with or without severe type, or in survivors vs nonsurvivors of COVID-19 patients. RESULTS: A total of 124 studies were included in this analysis. A higher risk for severity was observed in COVID-19 patients with comorbidities. The pooled result in patients with hypertension (OR 2.57, 95% CI: 2.12-3.11), diabetes (OR 2.54, 95% CI: 1.89-3.41), cardiovascular diseases (OR 3.86, 95% CI: 2.70-5.52), chronic obstractive pulmonary disease (OR 2.71, 95% CI: 1.98-3.70), chronic kidney disease (OR 2.20, 95% CI: 1.27-3.80), and cancer (OR 2.42, 95% CI: 1.81-3.22) respectively. All the comorbidities presented a higher risk of mortality. Moreover, the prevalence of acute cardiac injury is higher in severe group than in nonsevere group, and acute cardiac injury is associated with an increased risk for in-hospital mortality. CONCLUSION: Comorbidities and acute cardiac injury are closely associated with poor prognosis in COVID-19 patients. It is necessary to continuously monitor related clinical indicators of organs injury and concern comorbidities in COVID-19 patients.

The efficacy and safety of P2Y12 inhibitor monotherapy in patients after percutaneous coronary intervention.

The optimal antiplatelet therapy after percutaneous coronary intervention (PCI) remains to be elucidated. Monotherapy with a P2Y12 inhibitor may be inferior to dual antiplatelet therapy in patients after PCI. PubMed, EMBASE (by Ovidsp), Web of Science, and The Cochrane Library were searched from database inception to 2 October 2019. The composite of cardiovascular outcomes, all-cause mortality, myocardial infarction (MI), stroke, stent thrombosis, and major bleeding were evaluated. Pooled outcomes were presented as relative risk (RR) and 95% confidence intervals (CIs). A total of four trials randomizing 29 089 participants were included. Compared with the dual antiplatelet therapy group (n = 14 559), the P2Y12 inhibitor monotherapy group (n = 14 530) significantly decreased the incidence of bleeding events (2.0% vs 3.1%; RR: 0.60; 95% CI: 0.43-0.84; P = .005). There were no significant differences in all-cause mortality (1.3% vs 1.5%; RR: 0.87; 95% CI, 0.71-1.06; P = .16), myocardial infarction (2.1% vs 1.9%; RR, 1.06; 95% CI, 0.90-1.25; P = .46), stroke (0.6% vs 0.5%; RR, 1.18; 95% CI, 0.67-2.07; P = .57), or stent thrombosis (0.5% vs 0.4%; RR, 1.14; 95% CI, 0.81-1.61; P = .44) between the two groups. P2Y12 inhibitor monotherapy did not show any significant difference in the adverse cardiac and cerebrovascular events, but markedly decreased the risk of bleeding among patients after PCI vs dual antiplatelet therapy. However, it still needs to be further confirmed due to limited data.

Sulfur dioxide attenuates hypoxia-induced pulmonary arteriolar remodeling via Dkk1/Wnt signaling pathway.

OBJECTIVE: This study investigated the impact of SO2 on rats with hypoxic pulmonary vascular structural remodeling and its possible mechanisms. MATERIALS AND METHODS: Pulmonary vascular morphological change was examined by HE staining. RNA-based high-throughput sequencing (RNA-seq) was performed to detect differential expression of mRNAs in Normal and Hypoxia-induced Pulmonary hypertension (HPH) rats. The Real-time quantitative RT-PCR (q RT-PCR) was used for validation of wnt7b, sfrp2, cacna1f, DKK1, CaSR and vimentin mRNA expression levels. Protein levels of CaSR, Vimentin, Caspase3, E-cadherin and P-Akt1/2/3 were detected by Western blot and immunohistochemistry. RESULTS: This study showed that SO2 significantly attenuated the interstitial thickening and prominent media hypertrophy of pulmonary arteries. SO2 downregulated p-Akt1/2/3 protein level and upregulated E-cadherin protein level in lung tissues, which inhibited the proliferation and epithelial-to-mesenchymal transition (EMT) in HPH rats. RNA-seq and PCR validation results showed that levels of Wnt7b, Sfrp2 and Cacna1f mRNAs decreased and Dkk1 mRNA level increased obviously in HPH rats. Moreover, SO2 attenuated the mRNA and protein level of CaSR, which was activated in HPH rats and resulted in the proliferation of PASMCs. Besides, the mRNA and protein expression of vimentin in PASMCs significantly reduced after SO2 treatment. CONCLUSION: Together, these findings indicate that SO2 could attenuate hypoxia-induced pulmonary arteriolar remodeling and may suppress the proliferation and migration of PASMCs at least in part through the Dkk1/Wnt signaling pathway.

Targeted resequencing reveals genetic risks in patients with sporadic idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a genetic heterogeneous disease with high mortality and poor prognosis. However, a large fraction of genetic cause remains unexplained, especially in sporadic IPF (∼80% IPF). By systemically reviewing related literature and potential pathogenic pathways, 92 potentially IPF-related genes were selected and sequenced in genomic DNAs from 253 sporadic IPF patients and 125 matched health controls using targeted massively parallel next-generation sequencing. The identified risk variants were confirmed by Sanger sequencing. We identified two pathogenic and 10 loss-of-function (LOF) candidate variants, accounting for 4.74% (12 out of 253) of all the IPF cases. In burden tests, rare missense variants in three genes (CSF3R, DSP, and LAMA3) were identified that have a statistically significant relationship with IPF. Four common SNPs (rs3737002, rs2296160, rs1800470, and rs35705950) were observed to be statistically associated with increased risk of IPF. In the cumulative risk model, high risk subjects had 3.47-fold (95%CI: 2.07-5.81, P = 2.34 × 10-6 ) risk of developing IPF compared with low risk subjects. We drafted a comprehensive map of genetic risks (including both rare and common candidate variants) in patients with IPF, which could provide insights to help in understanding mechanisms, providing genetic diagnosis, and predicting risk for IPF.

Sulfur dioxide upregulates the inhibited endogenous hydrogen sulfide pathway in rats with pulmonary hypertension induced by high pulmonary blood flow.

Pulmonary hypertension (PH) is an important pathophysiological process in the development of many diseases. However, the mechanism responsible for the development of PH remains unknown. The objective of the study was to explore the possible impact of sulfur dioxide (SO2) on the endogenous hydrogen sulfide (H2S) pathway in rats with PH induced by high pulmonary blood flow. Compared with sham group, the systolic pulmonary artery pressure (SPAP) in the shunt group was significantly increased, along with the increased percentage of muscularized arteries and partially muscularized arteries of small pulmonary arteries. Compared with the shunt group, SPAP in the shunt+SO2 group was significantly decreased, and the percentage of muscularized pulmonary arteries was also decreased. Additionally, rats that developed PH had significantly lower levels of SO2 concentration, aspartate aminotransferase (AAT) activity, protein and mRNA expressions of AAT2 in pulmonary tissues. Administration of an SO2 donor could alleviate the elevated pulmonary arterial pressure and decrease the muscularization of pulmonary arteries. At the same time, it increased the H2S production, protein expression of cystathionine-γ-lyase (CSE), mRNA expression of CSE, mercaptopyruvate transsulphurase (MPST) and cystathionine-ß-synthase (CBS) in the pulmonary tissue of the rats. The results suggested that endogenous SO2/AAT2 pathway and the endogenous H2S production were downregulated in rats with PH induced by high pulmonary blood flow. However, SO2 could reduce pulmonary arterial pressure and improve the pulmonary vascular pathological changes in association with upregulating endogenous H2S pathway.

Endogenous generation of sulfur dioxide in rat tissues.

While sulfur dioxide (SO(2)) has been previously known for its toxicological effects, it is now known to be produced endogenously in mammals from sulfur-containing amino acid L-cysteine. L-cysteine is catalyzed by cysteine dioxygenase (CDO) to L-cysteinesulfinate, which converts to ß-sulfinylpyruvate through transamination by aspartate aminotransferase (AAT), and finally spontaneously decomposes to pyruvate and SO(2). The present study explored endogenous SO(2) production, and AAT and CDO distribution in different rat tissue. SO(2) content was highest in stomach, followed by tissues in the right ventricle, left ventricle, cerebral gray matter, pancreas, lung, cerebral white matter, renal medulla, spleen, renal cortex and liver. AAT activity and AAT1 mRNA expression were highest in the left ventricle, while AAT1 protein expression was highest in the right ventricle. AAT2 and CDO mRNA expressions were both highest in liver tissue. AAT2 protein expression was highest in the renal medulla, but CDO protein expression was highest in liver tissue. In all tissues, AAT1 and AAT2 were mainly distributed in the cytoplasm rather than the nucleus. These observed differences among tissues endogenously generating SO(2) and associated enzymes are important in implicating the discovery of SO(2) as a novel endogenous signaling molecule.

1,25-Dihydroxyvitamin D3 ameliorates podocytopenia in rats with adriamycin-induced nephropathy.

OBJECTIVE: To investigate the role of α3ß1 integrin and α/ß-dystroglycan in protective effects of 1,25(OH)2D3 on podocytes in rats with adriamycin-induced nephropathy. METHODS: Sprague-Dawley rats were randomly divided into three groups: control group (NC), nephropathy group (NE), and nephropathy+1,25(OH)2D3 group (ND). Rats in NE and ND group were injected intravenously with adriamycin (0.1 mg/10 g body weight) to induce nephropathy, and those in ND group were then subcutaneously treated with 1,25(OH)2D3 for 8 weeks. Urinary protein level, number of urine podocytes, foot process width and glomerulosclerotic index were determined. Nephrin and podocin mRNA and protein expressions were determined by RT-PCR and western blot, respectively. Podocyte density and expressions of α3ß1 integrin and α/ß-dystroglycan (DG) were analyzed by immunohistochemistry and western blot, respectively. RESULTS: The increase in proteinuria, podocyturia and width of foot process in NE group were ameliorated after treatment with 1,25(OH)2D3 for 8 weeks. The glomerulosclerotic index was significantly decreased in ND group when compared with NE group. The podocyte density in ND group (10.3±1.64 cells/glomerulus) was significantly higher than that in NE group (8.43±1.75 cells/glomerulus) (p=0.008). 1,25(OH)2D3 treatment could significantly up-regulate the mRNA and protein expressions of nephrin and podocin, and the protein expressions of α3ß1 integrin and α/ß-DG. CONCLUSION: The expressions of nephrin, podocin, α3ß1 integrin and α/ß-DG were decreased in rats with nephropathy. However, 1,25(OH)2D3 treatment could significantly up-regulate the expressions of nephrin, podocin, α3ß1 integrin and α/ß-DG proteins which might suppress podocyte detachment and podocytopenia.

1, 25-dihydroxyvitamin D3 decreases adriamycin-induced podocyte apoptosis and loss.

BACKGROUND: Selective proteinuria is frequently observed in glomerular diseases characterized by podocyte injury. Although, 1,25-dihydroxyvitamin D3 [1,25(OH)(2)D(3)] has potential therapeutic effects on chronic kidney diseases through decreasing podocyte loss, the mechanism underlying the beneficial effects of 1,25(OH)(2)D(3) on podocytes remains still unknown. The present study tested the hypothesis that 1,25(OH)(2)D(3) directly reduced podocyte apoptosis and loss. METHODS: Sprague-Dawley (SD) rats were randomly assigned into three groups: Adriamycin (ADR) group (n=15), ADR+1,25-(OH)(2)D(3) group (n=16), and control group (n=16). Rats in ADR+1,25-(OH)(2)D(3) group were treated with 1,25(OH)(2)D(3) for 8 weeks. The number of podocytes and foot process width (FPW) were detected by transmission electron microscopy. The number of apoptotic podocytes per glomerulus and that of apoptotic nuclei and caspase-3 activity in cultured podocytes were determined by TUNEL staining. The average number of podocytes per glomerulus was quantified by immunohistochemistry. Expressions of p-Smad2/3, p-Smad1/5/8, Fas, Fas-Associated protein with Death Domain (FADD), Bax, and Bcl-2 proteins were examined by Western blot assay. RESULTS: Compared with control group, proteinuria, FPW, apoptotic podocytes, caspase-3 activity, the protein expressions of p-Smad2/3, Fas, FADD, and Bax were significantly increased, podocyte density, p-Smad1/5/8 and Bcl-2 expression were decreased in ADR group. 1,25(OH)(2)D(3) significantly reduced proteinuria, FPW, caspase-3 activity, expressions of p-Smad2/3, Fas, FADD, and Bax and apoptosis of podocytes, but increased serum albumin, number of viable podocytes , p-Smad1/5/8 and Bcl-2 expression in ADR treated rats. CONCLUSION: ADR-induced podocyte apoptosis was associated with the imbalance of p-Smad2/3, p-Smad1/5/8 the activity of caspase-3 and aberrant expressions of, Fas, FADD, Bax and Bcl-2. The beneficial effects of 1,25(OH)(2)D(3 )on podocytes may be attributable to inhibit podocyte apoptosis and the amelioration of podocytopenia.