Following the publication of the above paper, it was drawn to the Editor's attention by an interested reader that the CD‑2AP and podocin protein blots shown in Fig. 3A on p. 6 were strikingly similar, suggesting that the same data had apparently been used to represent the two different proteins. The authors have been contacted by the Editorial Office to offer an explanation for the apparent duplication of data in this figure, and we are awaiting their response. Owing to the fact that the Editorial Office has been made aware of potential issues surrounding the scientific integrity of this paper, we are issuing an Expression of Concern to notify readers of this potential problem while the Editorial Office continues to investigate this matter further. [International Journal of Molecular Medicine 47: 27, 2021; DOI: 10.3892/ijmm.2021.4860].

Diabetic cardiomyopathy (DbCM) is characterized by metabolic remodeling and energetic stress independent of coronary artery disease. Increased reliance on fatty acid and ketone body metabolism has been observed in DbCM, but the regulatory mechanisms linking altered substrate utilization to myocardial dysfunction remain poorly understood. In particular, lysine β-hydroxybutyrate (Kbhb), a ketone body-derived post-translational modification, has emerged as a potentially critical regulator, but has not been fully investigated. We conducted a comprehensive multi-omics study integrating metabolomics, transcriptomics, proteomics, and Kbhb-specific proteomics on myocardial tissues in a well-established mouse model of DbCM. Kbhb-modified proteins were systematically mapped and quantified, followed by motif, subcellular localization, and protein–protein interaction analyses. DbCM cardiac tissue exhibited coordinated upregulations of fatty acid β-oxidation, ketone metabolism, and tricarboxylic acid cycle activity at the transcriptomic, proteomic, and metabolomic levels. Kbhb profiling revealed extensive mitochondrial protein modification, with Atp5f1a-K239 identified as a key modification site strongly correlated with β-hydroxybutyrate and isocitric acid concentrations. This study identifies Kbhb as a potential metabolic-epigenetic modifier linking ketone body availability to the regulation of mitochondrial proteins in DbCM. Our findings provide novel insights into metabolic-epigenetic crosstalk and identify potential therapeutic targets for interventions to restore mitochondrial function in alleviating diabetic heart disease.

Mitochondria and mitochondrial proteins represent attractive pharmacological candidates in the search for novel molecular targets to counteract the onset of hypertensive heart disease (HHD). In this work, we aimed to dissect the role and mechanism of mitochondrial ribosomal protein S21 (Mrps21) and Mrps15 in modulating mitochondrial dysfunction during HHD. Mrps15/Mrps21 expression was reduced in myocardial tissues of HHD mice induced by a 5-week gavage of L-NAME (70 mg/kg). Knockdown of Mrps15/Mrps21 inhibited mitochondrial translation in cardiomyocytes, which resulted in depolarization of mitochondrial membrane potential, impaired mitochondrial respiration, reduced membrane translocation of nuclear-encoded mitochondrial proteins, and mitochondrial reactive oxygen species production associated with reduced mitochondrial glutaredoxin-2. Mrps15/Mrps21 ameliorated myocardial injury associated with mitochondrial translation, thereby restoring cardiac function in mice. Zinc fingers and homeoboxes protein 1 (Zhx1) promoted the transcription of Mrps15/Mrps21. Zhx1 activator mithramycin treatment or Zhx1 overexpression ameliorated mitochondrial damage in HHD mice and L-NAME/Ang Ⅱ-stimulated cardiomyocytes, whereas combined silencing of Mrps15/Mrps21 compromised the protective effect of Zhx1 on cardiomyocytes. Our results demonstrate that Zhx1-mediated activation of Mrps15/Mrps21 transcription inhibits HHD progression through the mitochondrial pathway, and a potential therapeutic strategy for the clinical management of HHD is represented by pharmacological activation of Zhx1.

Liver fibrosis represents a major unmet clinical challenge, and induction of hepatic stellate cell (HSCs) senescence has emerged as a promising therapeutic strategy to halt or reverse fibrotic progression. PPARγ is a key regulator of HSCs quiescence; however, the downstream molecular mechanisms mediating its pro-senescence effects remain poorly defined. Here, we demonstrate that PPARγ expression is markedly reduced in a CCl₄-induced mouse liver fibrosis model and that its restoration drives HSC inactivation and senescence. Through integrated bioinformatics analysis and functional validation in PPARγ-overexpressing HSC-T6 cells, we identified leukemia inhibitory factor receptor (LIFR) as a direct transcriptional target of PPARγ. Mechanistically, PPARγ upregulates LIFR to suppress STAT3 phosphorylation, thereby downregulating fibrosis markers CO Ⅰ and α-SMA, elevating P21 and γ-H2A.X, and reducing CCND1. Crucially, LIFR knockdown abolished all PPARγ-mediated effects, confirming its indispensable role in this axis. Furthermore, combined treatment with the STAT3 inhibitor WP1066 synergistically enhanced PPARγ-driven HSC senescence in a LIFR-dependent manner. These findings establish a PPARγ-LIFR-STAT3 signaling cascade as a critical regulator of HSCs fate, and suggest that pharmacological activation of this axis represents a tractable approach for fibrosis resolution.

Background and AimLysine lactylation (Kla) has emerged as a novel posttranslational modification implicated in various disease processes, yet its role in diabetic cardiomyopathy (DCM) pathogenesis remains unknown. The objective of this study was to ascertain whether protein lactylation is involved in DCM progression.MethodsProteomic and lactate analysis via liquid chromatography with tandem mass spectrometry was performed on the heart tissues of db/m mice (as the control group) and db/db mice (as the DCM group). Subsequently, a series of bioinformatics analyses was employed to analyze the Kla site and Kla-modified proteins in the two groups.ResultsBioinformatics analysis revealed a greater abundance of Kla sites in the DCM group than in the control group. In addition, subcellular localization analysis indicated that Kla-modified proteins were predominantly located in the cytoplasm and mitochondria. Protein lactylation modification mainly occurred on histone H2, and in comparison to the control group, modification of the H4C1-K32 site was notably elevated in the DCM group. Furthermore, 113 significantly modified Kla sites were associated with 78 modified proteins in the DCM group, whereas 37 significantly modified Kla sites were associated with 25 modified proteins in the control group. These Kla-modified proteins participated in biological processes and pathways related to glucose metabolism and DCM. Finally, five candidate sites were identified using random forest, LASSO regression, support vector machine-recursive feature elimination, and logistic regression: A2ASS6_K928_Ttn, A2ASS6_K13499_Ttn, Q61425_K212_Hadh, Q8K2B3_K517_Sdha, and Q9R0Y5_K100_Ak1.ConclusionsOur findings suggest that protein lactate modification in the lactylome and proteome could be a promising treatment for DCM. This provides a reliable basis for further investigating the roles of Kla and Kla-modified proteins to develop new and effective therapeutic targets for treating DCM.

ABSTRACT As a commonly known aggressive liver-related manifestation within the spectrum of metabolic syndrome with a significant risk of progressing to cirrhosis and hepatocellular carcinoma, metabolic dysfunction-associated steatohepatitis (MASH) is closely intertwined with obesity, insulin resistance, and dyslipidemia. Although the gut microbiota is implicated in MASH progression, the underlying mechanisms require further investigation. In this study, we sought to combine the analysis of the liver transcriptome, circulating metabolome, and gut microbiota to investigate the potential molecular mechanisms underlying the reciprocal regulation between gut microbiota and liver immune signaling. We utilized a high-fat and methionine/choline-deficient diet (HFMCD)-induced MASH model in a db/db mouse. Following annotation analysis using KEGG and Metorigin, a comprehensive correlation analysis was conducted among these genes and specific metabolites (such as L-glutamine, isocitric acid, putrescine, pyroglutamic acid, rhamnose) and gut microbiota genera (Enteroccus and Romboutsia). The results revealed intricate interactions among the liver’s immune microenvironment, the metabolome, and the gut microbiota. These interactions suggest a potential regulatory mechanism for metabolic disorders and immune responses.IMPORTANCEOur multi-omics analysis showed that the interactions between gut microbiota and liver immune responses mediated by the disorders in lipid, amino acid, and glucose metabolism are associated with activation of the JAK-STAT and NF-κB signaling pathway in MASH. The multi-omics analysis provides valuable insights into the interactions among microbiota, circulating metabolites, and immune signaling. These insights can be harnessed to enhance the management of MASH.

Astragaloside IV (AS-IV) is an active component of Astragalus membranaceus, which has a prominent role in cardiovascular diseases. AS-IV has been reported to alleviate vascular endothelial dysfunction and promote angiogenesis. However, its function in hypertensive heart disease (HHD), a key underlying mechanism for cardiovascular morbidity and mortality, remains to be defined. The objective here is to investigate the inhibiting effect of AS-IV on HHD. HHD mice were induced by N(omega)-nitro-L-arginine methyl ester (L-NAME, LN), followed by AS-IV treatment. LN caused arterial endothelial dysfunction and cardiomyocyte injury in mice, while AS-IV ameliorated the pathological changes. Moreover, LN reduced the viability of arterial endothelial cells and cardiomyocytes and diminished the migration and angiogenic capacity of arterial endothelial cells, which were alleviated by AS-IV. AS-IV ameliorated LN-induced loss of retinoic acid receptor RXR-alpha (RXRA) and promoted the transcription of sirtuin 3 (SIRT3) via the RXRA/peroxisome proliferator-activated receptor gamma (PPARG) heterodimer. Knockdown of RXRA resulted in a loss of the therapeutic effect of AS-IV, and the progression of HHD caused by knockdown of RXRA was reversed by PPARG or SIRT3 overexpression. Hence, we propose that AS-IV promotes the expression of RXRA in HHD and mediates the transcription of SIRT3 through RXRA/PPARG, thereby ameliorating endothelial dysfunction and cardiomyocyte injury. KEY MESSAGES: AS-IV inhibits LN-induced HHD in mice and cardiomyocyte injury. AS-IV promotes endothelial cell migration and angiogenesis. AS-IV inhibits the loss of RXRA expression induced by LN. RXRA/PPARG heterodimer regulates the transcriptional expression of SIRT3. The therapeutic effect of AS-IV on HHD is dependent on RXRA/PPARG/SIRT3 signaling.

It is well known that gut microbial imbalance is a potential factor for the occurrence and development of diabetes mellitus (DM) and its complications. Moreover, the heart and gut microbiota can regulate each other through the gut-metabolite-heart axis. In this study, metagenomics, metabolomics, and transcriptomics were chosen to sequence the changes in gut microbiota, serum metabolite levels, and differentially expressed genes (DEGs) in leptin receptor-deficient db/db mice and analyze the correlation between serum metabolites and gut microbiota or DEGs. According to the results, there were significant differences in the 1,029 cardiac genes and 353 serum metabolites in diabetic mice of the db/db group, including DEGs enriched in the PPAR signaling pathway and increased short-chain carboxylic acids (CAs), when compared with the normal db/m group. According to metagenomics, the gut microbiota of mice in the db/db group were disrupted, and particularly Lachnospiraceae bacteria and Oscillospiraceae bacteria significantly decreased. Also, according to the Pearson correlation analysis, a significant positive correlation was found between CAs and PPAR signaling pathway-related DEGs, and a negative correlation was found between CAs and the abundance of the above-mentioned species. To sum up, type 2 diabetes mellitus (T2DM) can upregulate the expression of partial cardiac genes through the levels of serum short-chain CAs affected by gut microbiota, thus playing a role in the occurrence and development of diabetic cardiomyopathy (DCM). IMPORTANCE Our research results clearly link the changes in heart genes of T2DM and normal mice with changes in serum metabolites and gut microbiota, indicating that some genes in biological processes are closely related to the reduction of protective microbiota in the gut microbiota. This study provides a theoretical basis for investigating the mechanism of DCM and may provide preliminary evidence for the future use of gut microbiota therapy for DCM.

Sirtuin 5 (SIRT5), localized in the mitochondria, has been identified as a protein desuccinylase and demalonylase in the mitochondria since the depletion of SIRT5 boosted the global succinylation and malonylation of mitochondrial proteins. We investigated the role of SIRT5 in diabetic cardiomyopathy (DCM) and identified the mechanism regarding lysine demalonylation in this process. Wild-type and SIRT5 knockout mice were induced with DCM, and primary cardiomyocytes and cardiac fibroblasts extracted from wild-type and SIRT5 knockout mice were subjected to high glucose (HG). SIRT5 deficiency exacerbated myocardial injury in DCM mice, aggravated HG-induced oxidative stress and mitochondrial dysfunction in cardiomyocytes, and intensified cardiomyocyte senescence, pyroptosis, and DNA damage. DCM-induced SIRT5 loss diminished glutathione S-transferase P (GSTP1) protein stability, represented by significantly increased lysine malonylation (Mal-Lys) modification of GSTP1. SIRT5 overexpression alleviated DCM-related myocardial injury, which was reversed by GSTP1 knockdown. Reduced SIRT5 transcription in DCM resulted from the downregulation of SPI1. SPI1 promoted the transcription of SIRT5, thereby ameliorating DCM-associated myocardial injury. However, SIRT5 deletion resulted in a significant reversal of the protective effect of SPI1. These observations suggest that SPI1 activates SIRT5 transcriptionally to mediate GSTP1 Mal-Lys modification and protein stability, thus ameliorating DCM-associated myocardial injury.

Cardiac hypertrophy is frequently associated with ventricular dysfunction and heart failure. Paeoniflorin, has been widely used to treat cardiovascular dysfunction-related diseases. However, the underlying mechanism has been unclear. Here, we investigated the potential inhibitory effects and mechanism of paeoniflorin on oxidative stress of cardiac hypertrophy induced by angiotensin II (AngII) in vitro. Using MTS assay, qRT-PCR, WGA staining assay, and western blot, different dosages (50-400 & mu;M) of paeoniflorin were utilized to examine the antihypertrophy effects on H9c2 cells. Western blot examination revealed the presence of apoptosis-related proteins Bax, Bcl2, and Cytc, antioxidative stress-related proteins Nrf2, HO-1, SOD, and CAT, and mitophagyrelated proteins PINK1 and Parkin. qRT-PCR was used to detect the mRNA expression of Bax, Bcl2, Nrf2, and HO-1. TUNEL, caspase3/9 enzyme viability, and MDA, T-AOC, and superoxide levels were all evaluated using commercial kits.The fluorescent probes DCFH-DA and JC-1 were employed to measure cellular ROS and MMP levels. Nrf2 siRNA was utilized to investigate Nrf2's role in paeoniflorin-treated cardiac hypertrophy. Paeoniflorin dramatically reduced cell section area (CSA) and hypertrophic marker (ANP, BNP) expression while inhibiting oxidative stress by modulating ROS and MDA, CAT, SOD, and T-AOC levels. Furthermore, in AngIIinduced cardiomyocyte hypertrophy, paeoniflorin restores H9c2 apoptosis by restoring Bax, Bcl-2 Cyt-C, Caspase 3, and Caspase 9 levels. Paeoniflorin also restored Nrf2/HO-1 and PINK1/Parkin expression, and its antiAngII activities were mediated by Nrf2, which was regulated by Nrf2 knockdown. In conclusion, Our data confirm that paeoniflorin alleviates cardiac hypertrophy through modulating oxidative stress and Nrf2 signaling pathway in vitro.

Because of the advancement of bioabsorbable polymers and thinner struts, bioabsorbable‐polymer sirolimus‐eluting stents (BP‐SES) with ultrathin struts may be related to superior performance when compared to durable‐polymer drug‐eluting stents (DP‐DES) with thin struts. Nonetheless, the long‐term safety of ultrathin BP‐SES in acute coronary syndrome (ACS) remains unknown.

Gut microbial dysbiosis has always served as a potential factor in the occurrence and development of liver fibrosis. Liver and gut microflora can regulate each other through the gut-liver axis. In this study, the 16S rRNA and RNA-seq were chosen to sequence gut microbiota alteration and liver differentially expressed genes (DEGs) in carbon tetrachloride (CCl4) included-liver fibrosis mice, and analyze the correlations between gut microbiota constituents and DEGs. Results indicated that, CCl4 significantly increased the abundance of Desulfobactera in the phylum level, destroyed gut microbiota balance in the genus levels, especially Enterorhabdus and Desulfovibrio. Through analysis, 1416 genes were found differentially expressed in mice liver tissue in the CCl4 Group, compared with the Control Group; and the DEGs were mainly involved in the lipid metabolic process and immune system process. The correlation analysis revealed that the relative abundance of microbiota phylum (Desulfobactera) and genus (Enterorhabdus and Desulfovibrio) was negatively correlated with the metabolism related genes, while positively correlated with immune-related genes and the genes enriched in PI3K-Akt signaling pathway. To sum up, CCl4 can partially regulate gene expression in metabolism, immune response and the PI3K/Akt pathway, and further maintain the stability of the gut environment in liver fibrosis mice.

Background: Ferroptosis is a novel form of nonapoptotic regulatory cell death that is involved in the pathogenesis of diabetic complications, including diabetic cardiomyopathy (DCM). Recent studies have shown that spermine (SPM) may have a protective effect against hyperglycemia in mammals. However, it is still unclear whether SPM can negatively regulate ferroptosis in diabetic mice.Methods: We investigated the effects of SPM on ferroptosis in diabetic mice induced by streptozotocin (STZ) in vivo, as well as its impact on high glucose (HG)-stimulated HL-1 cardiomyocytes injury in vitro. We used various methods to evaluate cardiomyocyte ferroptosis injury and the effects of SPM, including echocardiographic analysis, electron microscopy, serum-related markers, immunohistochemistry, immunofluorescence, and immunoblotting. We also explored the effect of thioredoxin-interacting protein (TXNIP) on SPM in regulating the ferroptosis in HG-induced HL-1 cells through TXNIP siRNA transfection. Results: Mice induced with STZ showed a significant increase in blood glucose, food, and water intake (p < 0.05), but decreased body weight and weakened cardiac function (p < 0.05). The level changes of superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), iron (Fe2+), lipid reactive oxygen species (ROS) production as well as the expression of ferroptosis marker proteins (acyl-CoA synthetase long-chain family 4 (ACSL4), glutathione peroxidase 4 (GPX4), and solute carrier family 7 member 11 (SLC7A11)) and redox-related protein (TXNIP, nuclear factor erythroid 2-related factor 2 (NRF2), and heme oxygenase 1 (HO-1)) verified that diabetes or HG level aggravated lipid peroxidation, iron overloading and oxidative damage, thereby leading to ferroptosis in cardiomyocytes (p < 0.05). However, SPM treatment or interference with TXNIP expression significantly ameliorated cardiac injury in DCM mice caused by ferroptosis and HG-induced injury in cardiomyocytes.Conclusions: In general, these findings suggest that SPM can be used to prevent DCM by inhibiting the TXNIP-ferroptosis signaling loop. This treatment strategy is brand-new and potentially effective for DCM.

Background:The main pathological feature of diabetic cardiomyopathy (DCM) caused by diabetes mellitus is myocardial fibrosis.According to recent studies in cardiology, it has been suggested that spermidine (SPD) has cardioprotective properties.Aims: To explore the role and mechanism of SPD in alleviating myocardial fibrosis of DCM.Study Design: In vivo and in vitro study.Methods: Type 2 diabetic mice and primary neonatal mouse cardiac fibroblasts (CFs) were selected.Measurements of serum-related markers, echocardiographic analysis, and immunohistochemistry were used to evaluate myocardial fibrosis injury and the effects of SPD.The proliferation and migration of CFs undergoing different treatments were studied.Immunoblotting and real-time quantitative reverse transcription polymerase chain reaction were used to demonstrate molecular mechanisms.Results: In vivo immunoblotting analysis indicated a downregulation of ornithine decarboxylase and an upregulation of SPD/spermine N1-acetyltransferase. We observed cardiac dysfunction in diabetic mice after 12 weeks.However, the administration of exogenous SPD improved cardiac function, decreased collagen deposition, and reduced myocardial tissue damage.mRNA expression levels of NLRP3, Caspase-1, GSDMD-N, interleukin (IL)-1β, IL-17A, and IL-18 were increased and suppressed in the myocardium of db/db mice upon treatment with SPD.SPD inhibited the proliferation, migration, and collagen secretion of high-glucose-treated fibroblasts in vitro.SPD inhibits the activation of the TGF-β1/Smad signaling pathway and decreases collagen deposition by reducing pyroptosis and Smad-7 ubiquitination levels. Conclusion:Based on our findings, SPD may have potential applications in protecting against the deterioration of cardiac function in patients with DCM due to a significant new mechanism for diabetic myocardial fibrosis that we discovered.

Diabetic nephropathy (DN) is a major microvascular complication of diabetes that can lead to end-stage renal disease. Podocytes constitute the last barrier of glomerular filtration, whose damage are the direct cause of proteinuria. Dopamine receptors are involved in the regulation of diabetes-induced glomerular hyperfiltration, and only dopamine 1 receptor (D1R) can be amplified in cultured mouse podocytes. However, the exact effect of D1R on diabetic podocytes remains unclear. This study aims to investigate the protective role of D1R activation on diabetic podocytes injury in vivo and vitro as well as its potential mechanism. We observed D1R protective effect respectively in streptozotocin (STZ)-induced type 1 diabetes (T1D) mice as well as mouse podocytes (MPC5) cultured in high glucose (HG, 40 mM) medium. It showed that D1R and podocyte-associated proteins (Podocin, CD2AP and Nephrin) expression were significantly decreased both in the T1D mice (fed for 8 and 12 weeks) and HG-cultured MPC5 cells, while the NOX-5 expression increased. In T1D mice, the levels of 24-h urine protein, serum creatinine and urinary 8-OHdG were increased in a time-dependent manner, at the same time, hematoxylin-eosin (HE) staining and electron microscope observed the kidney lesion and podocytes injury. In vitro, HG induced podocytes oxidative stress and apoptosis, which could be inhibited by SKF38393 (a D1R agonist) and N-acetyl-l-cysteine (NAC, a reactive oxygen species scavenger). Furthermore, there was a decreasing Podocin expression and a significant increasing NOX-5 expression in podocytes transfected with D1R-small interfering RNA (siRNA). More importantly, the expression of phospho-CREB (the PKA downstream transcription factor) was decreased and phospho-p38 MAPK was increased in HG-induced podocytes, which can respectively be activated or blocked by SKF38393, 8-Bromo-CAMP (a PKA activator), NAC, and SB20380 (a p38 MAPK inhibitor). In conclusion, D1R activation can protect diabetic podocytes from apoptosis and oxidative damage, in part through the PKA/NOX-5/p38 MAPK pathway.

Background. It is well-known that dysfunctions of vascular smooth muscle cells (VSMCs) act an essential part in vascular complications of diabetes. Studies have shown that circular RNAs (circRNAs) and microRNAs (miRNAs) play a crucial role in regulating cell functions. However, their influence on the proliferation, calcification, and autophagy of VSMCs remains to be further explored. Therefore, this study elucidates the role and mechanism of hsa_circRNA_0008028 in high glucose- (HG-, 30 mM) treated VSMCs in vitro. Methods. Quantitative real-time polymerase chain reaction (qRT-PCR) was chosen to detect the levels of hsa_circRNA_0008028, miR-182-5p, and tribble 3 (TRIB3). Then, dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to predict and verify the binding relationship between miR-182-5p and hsa_circRNA_0008028 or TRIB3. Cell counting kit-8 assay, 5-ethynyl-2 ′ -deoxyuridine (EdU) staining, corresponding commercial kits, and western blotting were used to measure indexes reflecting cell viability, proliferation, calcification, and autophagy of VSMCs, respectively. Results. In HG-induced VSMCs, hsa_circRNA_0008028 and TRIB3 were highly expressed, whereas miR-182-5p decreased. Meanwhile, cell proliferation, calcification, and autophagy could be repressed by silencing of hsa_circRNA_0008028. However, these effects can be eliminated by miR-182-5p inhibition. Furthermore, it was demonstrated that hsa_circRNA_0008028 could promote the expression of TRIB3, a target of miR-182-5p, by directly sponging miR-182-5p. The expression of TRIB3 was suppressed by hsa_circRNA_0008028 knockout, which was rescued by miR-182-5p inhibition. Conclusion. This study reveals that hsa_circRNA_0008028 can act as a sponge of miR-182-5p and promote HG-induced proliferation, calcification, and autophagy of VSMCs partly by regulating TRIB3.

High glucose (HG)-induced dysfunction of vascular endothelial cells plays a crucial role in the development of diabetic vascular complications. Inhibition of cystathionine γ-synthase/hydrogen sulfide (CSE/H2 S) pathway is one of the causes of vascular endothelial cell injury induced by HG. Dopamine D1 receptors (DR1) are widely expressed and regulate important physiological functions in the vascular system. However, the effect of DR1 inhibition on HG-induced vascular endothelial apoptosis by regulating the CSE/H2 S pathway is unclear. Therefore, we aimed to determine if DR1 can regulate the CSE/H2 S pathway and regulate the effect of DR1 on HG-induced apoptosis in human umbilical vein endothelial cells. In this study, we found that HG treatment significantly decreased the expression of DR1 and CSE and the endogenous content of H2 S; DR1 agonist SKF 38393 reversed these effects, while sodium hydrosulfide (NaHS) only increased CSE expression and the endogenous H2 S production and had no effect on DR1 expression. Meanwhile, HG significantly increased the intracellular calcium concentration ([Ca2+ ]i ), and SKF 38393 further increased HG-induced [Ca2+ ]i . In addition, HG increased the lactate dehydrogenase activity, malondialdehyde and reactive oxygen species contents, apoptotic rate, the expression of cleaved caspase-3, caspase-9, and cytochrome c, and the activity of phosphorylated-inhibitor of nuclear factor-kappaBα (NF-κBα) (p-IκBα) and phosphorylated-NF-κB (p-NF-κB), and reduced cell viability, superoxide dismutase activity, and Bcl-2 expressions. SKF 38393 and NaHS markedly reversed the effect of HG. The effect of SKF 38393 was similar to N-acetyl- l-cysteine (an inhibitor of oxidative stress) or pyrrolidinedithiocarbamate ammonium (an NF-kB inhibitor). Taken together, DR1 upregulates the CSE/H2 S pathway by increasing the [Ca2+ ]i , which inhibits HG-induced apoptosis via downregulating NF-κB/IκBα pathway in vascular endothelial cells.

Background. Diabetic cardiomyopathy (DbCM) is the main complication and the cause of high mortality of diabetes. Exploring the transcriptomics and proteomics of DbCM is of great significance for understanding the biology of the disease and for guiding new therapeutic targets for the potential therapeutic effect of spermine (SPM). Methods and Results. By using a mouse DbCM model, we analyzed the overall transcriptome and proteome of the myocardium, before/after treatment with SPM. The general state and cardiac structure and function changes of each group were also compared. Diabetes induced an increased blood glucose and serum triglyceride content, a decreased body weight, serum insulin level, and cardiac function-related indexes, accompanied by disrupted myocardial tissue morphology and ultrastructure damage. Using RNA sequencing (RNA-seq), we identified thousands of differentially expressed genes (DEGs) in DbCM with or without SPM treatment. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis demonstrated that the DEGs were significantly enriched in lipid metabolism and amino acid metabolism pathways. Specifically, quantitative real-time PCR (qRT-PCR) confirmed that SPM protected DbCM by reversing the expressions of lipid metabolism and amino acid metabolism-related genes, including Alox15, Gm13033, pla2g12a, Ptges, Pnpla2, and Acot1. To further reveal the pathogenesis of DbCM, we used proteome-based data-independent acquisition (DIA) and identified 139 differentially expressed proteins (DEPs) with 67 being upregulated and 72 being downregulated in DbCM. Venn intersection analysis showed 37 coexpressed genes and proteins in DbCM, including 29 upregulation and 8 downregulation in DbCM. In the protein-protein interaction (PPI) network constructed by the STRING database, the metabolism-related coexpressed genes and proteins, such as Acot2, Ephx2, Cyp1a1, Comt, Acox1, Hadhb, Hmgcs2, Acot1, Inmt, and Cat, can interact with the identified DEGs and DEPs. Conclusion. The biomarkers and canonical pathways identified in this study may hold the key to understand the mechanisms of DbCM pathobiology and provide new targets for the therapeutic effect of SPM against DbCM by targeting lipid and amino acid metabolism pathways.