Protective role of hydrogen sulfide against diabetic cardiomyopathy by inhibiting pyroptosis and myocardial fibrosis.

Diabetic cardiomyopathy (DCM) contributes significantly to the heightened mortality rate observed among diabetic patients, with myocardial fibrosis (MF) being a pivotal element in the disease's progression. Hydrogen sulfide (H2S) has been shown to mitigate MF, but the specific underlying mechanisms have yet to be thoroughly understood. A connection has been established between the evolution of DCM and the incidence of cardiomyocyte pyroptosis. Our research offers insights into H2S protective impact and its probable mode of action against DCM, analyzed through the lens of MF. In this study, a diabetic rat model was developed using intraperitoneal injections of streptozotocin (STZ), and hyperglycemia-stimulated cardiomyocytes were employed to replicate the cellular environment of DCM. There was a marked decline in the expression of cystathionine γ-lyase (CSE), a catalyst for H2S synthesis, in both the STZ-induced diabetic rats and hyperglycemia-stimulated cardiomyocytes. Experimental results in vivo indicated that H2S ameliorates MF and enhances cardiac functionality in diabetic rats by mitigating cardiomyocyte pyroptosis. In vitro assessments highlighted the induction of cardiomyocyte pyroptosis and the subsequent decline in cell viability under hyperglycemic conditions. However, the administration of sodium hydrosulfide (NaHS) curtailed cardiomyocyte pyroptosis and augmented cell viability. In contrast, propargylglycine (PAG), a CSE inhibitor, reversed the effects rendered by NaHS administration. Additional exploration indicated that the mitigating effect of H2S on cardiomyocyte pyroptosis is modulated through the ROS/NLRP3 pathway. In essence, our findings corroborate the potential of H2S in alleviating MF in diabetic subjects. This therapeutic effect is likely attributable to the regulation of cardiomyocyte pyroptosis via the ROS/NLRP3 pathway. This discovery furnishes a prospective therapeutic target for the amelioration and management of MF associated with diabetes.

AP39 through AMPK-ULK1-FUNDC1 pathway regulates mitophagy, inhibits pyroptosis, and improves doxorubicin-induced myocardial fibrosis.

Doxorubicin induces myocardial injury and fibrosis. Still, no effective interventions are available. AP39 is an H2S donor that explicitly targets mitochondria. This study investigated whether AP39 could improve doxorubicin-induced myocardial fibrosis. Doxorubicin induced significant myocardial fibrosis while suppressing mitophagy-related proteins and elevating pyroptosis-related proteins. Conversely, AP39 reverses these effects, enhancing mitophagy and inhibiting pyroptosis. In vitro experiments revealed that AP39 inhibited H9c2 cardiomyocyte pyroptosis, improved doxorubicin-induced impairment of mitophagy, reduced ROS levels, ameliorated the mitochondrial membrane potential, and upregulated AMPK-ULK1-FUNDC1 expression. In contrast, AMPK inhibitor (dorsomorphin) and ULK1 inhibitor (SBI-0206965) reversed AP39 antagonism of doxorubicin-induced FUNDC1-mediated impairment of mitophagy and secondary cardiomyocyte pyroptosis. These results suggest that mitochondria-targeted H2S can antagonize doxorubicin-induced pyroptosis and impaired mitophagy in cardiomyocytes via AMPK-ULK1-FUNDC1 and ameliorated myocardial fibrosis and remodeling.

Association of Urine Albumin to Creatinine Ratio With Cardiovascular Outcomes in Patients With Type 2 Diabetes Mellitus.

CONTEXT: The urinary albumin to creatinine ratio (UACR) is a widely used indicator of albuminuria and has predictive value for adverse cardiovascular events. OBJECTIVE: To evaluate the correlation between the UACR and the risk of developing major adverse cardiovascular events (MACEs) and total mortality in patients with type 2 diabetes mellitus (T2DM). METHODS: This post hoc analysis included 10 171 participants from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study and the ACCORD follow-up study (ACCORDION) with baseline UACR data. The natural logarithm (ln) of each UACR measurement was calculated. Univariate and multivariate Cox proportional hazard regression analyses were conducted to examine the association between the UACR and the risk of MACEs and total mortality. The additional predictive value of UACR was further evaluated. Similar methods were used to analyze the correlation between the UACR and MACEs and total mortality within the normal range. RESULTS: During a median follow-up period of 8.83 years, 1808 (17.78%) participants experienced MACEs, and there were 1934 (19.01%) total deaths. After adjusting for traditional cardiovascular risk factors, the multivariate analysis revealed a significant association between the UACR and the risk of MACEs and total mortality. The inclusion of UACR in the conventional risk model enhanced the predictive efficacy for MACEs and total mortality. CONCLUSION: An elevated UACR is associated with a higher risk of MACEs and total mortality in patients with T2DM, even when it falls within the normal range. The UACR improves prediction of MACE and total mortality risk in patients with T2DM.

Development and evaluation of a monoclonal antibody-based blocking ELISA to detect antibodies against the E2 protein of bovine viral diarrhea virus-1.

With the rapid development of cattle industry, bovine viral diarrhea virus (BVDV) is becoming widespread in China, which causes serious economic losses to the industry. Effective vaccination and viral surveillance are critical for the prevent and control of BVDV infection. In the present study, the immunogenic domain of E2 protein of BVDV-1 was expressed by prokaryotic pET-28a vector. Monoclonal antibodies (mAbs) against E2 protein were prepared and systemically examined by western blot, immunofluorescence assay, blocking ELISA (bELISA) and virus neutralization test (VNT). The mAb 1E2B3, which showed good reactivity and neutralizing activity to BVDV-1 strains, was selected for ELISA establishment. After a series of screening and optimization, a novel bELISA for highly sensitive and specific detection of BVDV-1 antibodies was established, using HRP-labeled 1E2B3 and recombinant E2 protein. ROC analysis of 91 positive and 84 negative reference bovine serum samples yielded the area under the curve (AUC) of 0.9903. A diagnostic specificity of 96.43 % and a sensitivity of 95.6 % were achieved when the cutoff value was set at 24.31 %. There was no cross reaction to the positive sera of classical swine fever virus (CSFV), BVDV-2, border disease virus (BDV), bovine parainfluenza virus type 3 (BPIV3), infectious bovine rhinotracheitis virus (IBRV), foot-and-mouth disease virus (FMDV), Mycoplasma bovis (M.bovis) and Brucella. The total agreement rate of bELISA with VNT was 93.96 % (249/265). In addition, the result of bELISA was positively correlated with neutralizing antibody titer, and the bELISA could well distinguish the serum samples before and after BVDV vaccination. These results indicate that the established bELISA in this study is specific, sensitive, simple and convenient, which provides technical support for the vaccine efficacy evaluation, prevention and control of BVD in the future.

Genotyping and biofilm formation of Mycoplasma hyopneumoniae and their association with virulence.

Mycoplasma hyopneumoniae, the causative agent of swine respiratory disease, demonstrates differences in virulence. However, factors associated with this variation remain unknown. We herein evaluated the association between differences in virulence and genotypes as well as phenotype (i.e., biofilm formation ability). Strains 168 L, RM48, XLW-2, and J show low virulence and strains 232, 7448, 7422, 168, NJ, and LH show high virulence, as determined through animal challenge experiments, complemented with in vitro tracheal mucosa infection tests. These 10 strains with known virulence were then subjected to classification via multilocus sequence typing (MLST) with three housekeeping genes, P146-based genotyping, and multilocus variable-number tandem-repeat analysis (MLVA) of 13 loci. MLST and P146-based genotyping identified 168, 168 L, NJ, and RM48 as the same type and clustered them in a single branch. MLVA assigned a different sequence type to each strain. Simpson's index of diversity indicates a higher discriminatory ability for MLVA. However, no statistically significant correlation was found between genotypes and virulence. Furthermore, we investigated the correlation between virulence and biofilm formation ability. The strains showing high virulence demonstrate strong biofilm formation ability, while attenuated strains show low biofilm formation ability. Pearson correlation analysis revealed a significant positive correlation between biofilm formation ability and virulence. To conclude, there was no association between virulence and our genotyping data, but virulence was found to be significantly associated with the biofilm formation ability of M. hyopneumoniae.

Duck sewage source coliphage P762 can lyse STEC and APEC.

Multiple pathogenic types or serotypes restrict treatment for colibacillosis. In addition, rising antibiotic resistance has heightened public awareness to prevent and control pathogenic Escherichia coli. The bacteriophage is a viable technique to treat colibacillosis as an alternative to antibiotics. P762, a coliphage isolated from duck farm sewage, was demonstrated to cloud lyse Shiga toxin-producing Escherichia Coli serotypes O157 and non-O157 (17/39), Avian pathogenic E. coli covered serotype O78, O83, and O9 (5/19), and other pathogenic Escherichia coli (5/17). Additional fundamental biological characteristics analysis revealed that P762 is stable at pH 3 ~ 11 and temperature between 4 °C and 60 °C, and its optimum multiplicity of infection (MOI) is 0.1. The one-step curve of P762 exhibited three bursts of growth stage: two rapid and one slow stage. Furthermore, the first rapid burst size is 80 CFU/PFU, the burst size of the slow stage is 10 CFU/PFU, and the second rapid burst size is about 990 CFU/PFU. In addition, P762 can form a "halo" on a double agar plate, implying that the phage secretes depolymerase. With 95.14% identity and 90% query coverage, genome sequence analysis revealed that P762 is most closely related to Escherichia phage DY1, which belongs to the genus Kayfunavirus. After screening using RAST and VFDB, no virulence factors were discovered in P762. In vitro antibacterial tests revealed that P762 has high bactericidal activity in lettuce leaves contaminated with STEC. In conclusion, phage P762 might be employed in the future to prevent and control pathogenic Escherichia coli.

Research Progress on Emerging Viral Pathogens of Small Ruminants in China during the Last Decade.

China is the country with the largest number of domestic small ruminants in the world. Recently, the intensive and large-scale sheep/goat raising industry has developed rapidly, especially in nonpastoral regions. Frequent trading, allocation, and transportation result in the introduction and prevalence of new pathogens. Several new viral pathogens (peste des petits ruminants virus, caprine parainfluenza virus type 3, border disease virus, enzootic nasal tumor virus, caprine herpesvirus 1, enterovirus) have been circulating and identified in China, which has attracted extensive attention from both farmers and researchers. During the last decade, studies examining the etiology, epidemiology, pathogenesis, diagnostic methods, and vaccines for these emerging viruses have been conducted. In this review, we focus on the latest findings and research progress related to these newly identified viral pathogens in China, discuss the current situation and problems, and propose research directions and prevention strategies for different diseases in the future. Our aim is to provide comprehensive and valuable information for the prevention and control of these emerging viruses and highlight the importance of surveillance of emerging or re-emerging viruses.

Temporal Dynamics of the Ruminant Type I IFN-Induced Antiviral State against Homologous Parainfluenza Virus 3 Challenge In Vitro.

Viruses have evolved diverse strategies to evade the antiviral response of interferons (IFNs). Exogenous IFNs were applied to eliminate the counteracting effect and possess antiviral properties. Caprine parainfluenza virus 3 (CPIV3) and bovine parainfluenza virus type 3 (BPIV3) are important pathogens associated with respiratory diseases in goat and cattle, respectively. To explore the feasibility of type I IFNs for control of CPIV3 and BPIV3 infection, the activated effects of IFN-stimulated genes (ISGs) and the immunomodulation responses of goat IFN-α were detected by transcriptomic analysis. Then, the antiviral efficacy of goat IFN-α and IFN-τ against CPIV3 and BPIV3 infection in MDBK cells was evaluated using different treatment routes at different infection times. The results showed that CPIV3 infection inhibited the production of type I IFNs, whereas exogenous goat IFN-α induced various ISGs, the IFN-τ encoding gene, and a negligible inflammatory response. Consequently, goat IFN-α prophylaxis but not treatment was found to effectively modulate CPIV3 and BPIV3 infection; the protective effect lasted for 1 week, and the antiviral activity was maintained at a concentration of 0.1 µg/mL. Furthermore, the antiviral activity of goat IFN-τ in response to CPIV3 and BPIV3 infection is comparable to that of goat IFN-α. These results corroborate that goat IFN-α and IFN-τ exhibit prophylactic activities in response to ruminant respiratory viral infection in vitro, and should be further investigated for a potential use in vivo.

Comprehensive analysis of codon usage patterns of porcine deltacoronavirus and its host adaptability.

The porcine deltacoronavirus (PDCoV) is a newly discovered pig enteric coronavirus that can infect cells from various species. In Haiti, PDCoV infections in children with acute undifferentiated febrile fever were recently reported. Considering the great potential of inter-species transmission of PDCoV, we performed a comprehensive analysis of codon usage patterns and host adaptation profiles of 54 representative PDCoV strains with the spike (S) gene. Phylogenetic analysis of the PDCoV S gene indicates that the PDCoV strains can be divided into five genogroups. We found a certain codon usage bias existed in the S gene, in which the synonymous codons are often ended with U or A. Heat map analysis revealed that all the PDCoV strains shared a similar codon usage trend. The PDCoV S gene with a dN/dS ratio lower than 1 reveals a negative selection on the PDCoV S gene. Neutrality analysis showed that natural selection is the dominant force in shaping the codon usage bias of the PDCoV S gene. Unexpectedly, host adaptation analysis reveals a higher adaptation level of PDCoV to Homo sapiens and Gallus gallus than to Sus scrofa. Compared to the USA lineage, the PDCoV strains in the Early China lineage and Thailand lineage were less adapted to their hosts, which indicates that the evolutionary process plays an important role in the adaptation ability of PDCoV. These findings of this study add to our understanding of PDCoV's evolution, adaptability, and inter-species transmission.

Molecular characterization and antimicrobial resistance profile of pathogenic Escherichia coli from goats with respiratory disease in eastern China.

Pathogenic Escherichia coli (E. coli) can cause a variety of intestinal and extra-intestinal infections in humans and animals. Similar with the intestinal disease, respiratory disease is also a major threat to the breeding industry of goats. But the reports on respiratory disease associated E. coli are very limited. In this study, E. coli and other pathogens were examined for the 77 submitted respiratory cases. The serotypes, virulence genes, phylogenetic group and antimicrobial resistance characteristics of the E. coli isolates were identified. The results showed that 34 cases (44.16%) were associated with E. coli and 22 cases showed mixed infections of E. coli with Mycoplasma ovipneumoniae, Mannheimia haemolytica or Pasteurella . Among the 49 E. coli isolates, O8 (32.65%), O9 (20.41%) and O89 (10.20%) were the predominant serotypes (31/49, 63.27%). 22 virulence genes were detected and the most prevalent genes were fimH (100%), yijp (100%), mat (97.96%), ompA (95.92%) ibeB (91.84%) and fyuA (77.55%). In addition, ibeA was detected in 6.12% (3/49) of the strains. Markers of extra-intestinal pathogenic E. coli (ExPEC) were also identified and 14 strains were classified as ExPECs. 14 (28.57%), 25 (51.02%), 3 (6.12%) and 7 (14.29%) strains belonged to phylogenetic group A, B1, B2 and D, respectively, and group A and B1 were the predominant ones. The E. coli strains showed high resistant (48.98%-100%) to the 14 selected antimicrobials and all of them were defined as multiple drug resistant (MDR) strains. This is the first systemically study on E. coli of goats respiratory diseases origin in eastern China. The results suggest that E. coli infection may play an important role in goat respiratory diseases and that goats are reservoir hosts of ExPECs, which needs continuous monitoring in the future.

Evaluation of the transcriptional regulatory efficacy of transcription regulatory sequences of porcine epidemic diarrhea virus.

Porcine epidemic diarrhea virus (PEDV) is a highly contagious enteropathogenic coronavirus causing severe watery diarrhea and high mortality in piglets. In order to investigate the role of the transcription regulatory sequences (TRSs) in regulation of gene expression and replication of PEDV, the enhanced green fluorescent protein (EGFP) gene, under control of different TRSs of PEDV, were inserted between the N gene and 3' UTR of the PEDV genome using a reverse genetic system. The EGFP expression from different chimeric PEDVs was analyzed for each TRS. TRSs of all the structural and accessory protein genes of PEDV positively regulate EGFP expression at different levels, and the TRS of M protein gene produced the highest level of EGFP. Moreover, this is the first study to show that exogenous gene could be inserted between N gene and 3' UTR of PEDV, and the EGFP insertion had no effect on PEDV replication. Taken together, our study enriched the information of PEDV TRSs on gene expression and replication of PEDV.

Transcriptome and Proteomic Analysis Reveals Up-Regulation of Innate Immunity-Related Genes Expression in Caprine Herpesvirus 1 Infected Madin Darby Bovine Kidney Cells.

Caprine herpesvirus 1 (CpHV-1) is a member of the alpha subfamily of herpesviruses, which is responsible for genital lesions and latent infections in goat populations worldwide. In this study, for the first time, the transcriptome and proteomics of CpHV-1 infected Madin Darby bovine kidney (MDBK) cells were explored using RNA-Sequencing (RNA-Seq) and isobaric tags for relative and absolute quantitation-liquid chromatography tandem mass spectrometry (iTRAQ-LC-MS/MS) technology, respectively. RNA-Seq analysis revealed 81 up-regulated and 19 down-regulated differentially expressed genes (DEGs) between infected and mock-infected MDBK cells. Bioinformatics analysis revealed that most of these DEGs were mainly involved in the innate immune response, especially the interferon stimulated genes (ISGs). Gene Ontology (GO) enrichment analysis results indicated that the identified DEGs were significantly mainly enriched for response to virus, defense response to virus, response to biotic stimulus and regulation of innate immune response. Viral carcinogenesis, the RIG-I-like receptor signaling pathway, the cytosolic DNA-sensing pathway and pathways associated with several viral infections were found to be significantly enriched in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database. Eleven selected DEGs (Mx1, RSAD2, IFIT1, IFIT2, IFIT5, IFIH1, IFITM3, IRF7, IRF9, OAS1X and OAS1Y) associated with immune responses were selected, and they exhibited a concordant direction both in RNA-Seq and quantitative real-time RT-PCR analysis. Proteomic analysis also showed significant up-regulation of innate immunity-related proteins. GO analysis showed that the differentially expressed proteins were mostly enriched in defense response and response to virus, and the pathways associated with viral infection were enriched under KEGG analysis. Protein-protein interaction network analysis indicated most of the DEGs related to innate immune responses, as DDX58(RIG-I), IFIH1(MDA5), IRF7, Mx1, RSAD2, OAS1 and IFIT1, were located in the core of the network and highly connected with other DGEs. Our findings support the notion that CpHV-1 infection induced the transcription and protein expression alterations of a series of genes related to host innate immune response, which helps to elucidate the resistance of host cells to viral infection and to clarify the pathogenesis of CpHV-1.

Caprine parainfluenza virus type 3 N protein promotes viral replication via inducing apoptosis.

Caprine parainfluenza virus type 3 (CPIV3) is one of the most important viral respiratory pathogens of goat. Accumulating evidence demonstrates that apoptosis is a cellular mechanism for the host response to pathogens, and it participates in regulating viral replication. However, there is little study on CPIV3-induced host cells apoptosis. In this study, primary goat tracheal epithelial (GTE) cells were established as a cellular model that is permissive to CPIV3 infection. Then, we showed that CPIV3 infection induced apoptosis in GTE cells, as determined by morphological changes, flow cytometry and TUNEL assay. Moreover, Caspase activity and the expression of pro-apoptotic genes further suggested that CPIV3 induced apoptosis by activating both the intrinsic and extrinsic pathways. Mechanistically, the ability of CPIV3 to induce apoptosis was activated by N protein, and the viral protein increased CPIV3 replication through effecting apoptosis. Overall, our findings showed that GTE cells that will enable further analysis of CPIV3 infection and offers novel insights into the mechanisms of CPIV3-induced apoptosis in host cells.

Effect of magnesium ammonium phosphate on the expression of adhesion molecules in sheep renal tubular epithelial cells.

Adhesion molecules play an important role in urinary calculus formation. The expressions of adhesion molecules in renal tubular has been reported in some animals. However, the role of adhesion molecules in the process of sheep urinary calculus formation is still unclear. The magnesium ammonium phosphate (MAP) is the main component of sheep urinary calculus. In this paper, the sheep renal tubular epithelial cells (RTECs) were isolated and treated with MAP, the expressions of osteopontin (OPN), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and apoptosis-related indicators caspase-3, Bcl-2 and Bax in RTECs were observed, the viability of RTECs was detected by Cell Counting Kit-8 (CCK-8). The levels of superoxide dismutase (SOD) and malondialdehyde (MDA), and the expressions of inflammatory factors Interleukin-6 (IL-6), Interleukin-1 (IL-1), Interleukin-17 (IL-17) and tumor necrosis factor-α (TNF-α) were measured by enzyme-linked immunosorbent (ELISA). The histopathological observation of kidney in urolithiasis sheep was made. The results showed that MAP could reduce the viability and SOD activity, enhance the activity of MDA significantly and promote the expressions of IL-1, IL-6, IL-17 and TNF-α of RTECs. By western blot and qPCR methods, the expressions of ICAM-1, VCAM-1 and OPN increased in 48 h. In addition, the expression of caspase-3 increased significantly and the ratio of Bcl-2/Bax reduced with exposure to MAP. The renal tissue structure was seriously damaged, the RTECs in urolithiasis sheep were degenerative and necrotic.

H2S improves doxorubicin-induced myocardial fibrosis by inhibiting oxidative stress and apoptosis via Keap1-Nrf2.

OBJECTIVE: We waimed to investigate whether H2S can relieve the myocardial fibrosis caused by doxorubicin through Keap1-Nrf2. METHODS: Sprague-Dawley (SD) rats were randomly divided into four groups: normal control group (Control); DOX model group (DOX); H2S intervention model group (DOX+H2S); H2S control group (H2S). DOX and DOX+H2S group were injected with doxorubicin (3.0 mg/kg/time) intraperitoneally. Both of the Control group and H2S groups were given normal saline in equal volume, 2 weeks later, DOX+H2S and H2S group were controlled with NaHS (56 µmol/kg/d) through the abdominal cavity, while the Control and DOX group were injected with normal saline of the same dosage intraperitoneally. RESULTS: Myocardial injury and myocardial cell apoptosis were significantly increased, the H2S content in myocardial tissue was remarkably down-regulated, the expression levels of MDA, Keap1, caspase-3, caspase-9, TNF-α, IL1ß, MMPs and TIMP-1 in rat myocardial tissue was significantly up-regulated (P< 0.05), and the expression levels of GSH, NQO1, Bcl-2 were down-regulated compared with those of control group. The above results can be reversed by the DOX+H2S group. There is no statistically significant difference between the Control group and the H2S control group. CONCLUSIONS: These results suggest that H2S can improve DOX-induced myocardial fibrosis in rats, and the keap1/Nrf2 signaling pathway, oxidative stress, inflammation, and apoptosis may be involved in the mechanism.

Hydrogen sulfide ameliorates doxorubicin­induced myocardial fibrosis in rats via the PI3K/AKT/mTOR pathway.

The present study aimed to determine the role and regulatory mechanism of hydrogen sulfide (H2S) in the amelioration of doxorubicin­induced myocardial fibrosis in rats. It is hypothesized that the PI3K/AKT/mTOR signaling pathway is regulated to inhibit endoplasmic reticulum stress (ERS) and autophagy to reduce myocardial fibrosis. A total of 40 adult male Sprague Dawley rats were randomly divided into 4 groups (n=10/group). The 4 groups included the normal control group (control group), model group [doxorubicin (Dox) group], H2S intervention model group (H2S+Dox group) and H2S control group (H2S group). The model used in the present study was constructed by administering intraperitoneal injections of doxorubicin (3.0 mg/kg every other day; total of 6 injections). In addition, the intervention factor, NaHS and the donor of H2S, was also administered by intraperitoneal injection (56 µmol/kg/day), which lasted a month. Pathological changes in the rats were observed using Masson staining and transmission electron microscopy, while the protein expression levels of MMPs/TIMPs, transforming growth factor­ß1, cystathionine lyase and PI3K/AKT/mTOR, which are autophagy­related and ERS­related proteins were detected in myocardial tissues using western blot analysis. The gene expression levels of collagen type I α­2 chain and collagen type III α­1 chain were detected using reverse transcription­quantitative PCR and the quantification of myocardial H2S content was performed using ELISA. In the Dox group compared with that in the control group, myocardial fibers were significantly disordered, while the protein expression levels of ERS­related and autophagy­related proteins were increased markedly, and the expression levels of PI3K/AKT/mTOR proteins were reduced markedly. The aforementioned changes were markedly reversed following H2S intervention, which indicated that H2S exerts a positive protective effect on doxorubicin­induced myocardial fibrosis. The protective mechanism of H2S intervention in myocardial fibrosis is hypothesized to be associated with the inhibition of overactivation of the ER and that of autophagy via upregulation of the PI3K/AKT/mTOR pathway.

Screening interferon antagonists from accessory proteins encoded by P gene for immune escape of Caprine parainfluenza virus 3.

The Caprine parainfluenza virus 3 (CPIV3) is a novel Paramyxovirus that is isolated from goats suffering from respiratory diseases. Presently, the pathogenesis of CPIV3 infection has not yet been fully characterized. The Type I interferon (IFN) is a key mediator of innate antiviral responses, as many viruses have developed strategies to circumvent IFN response, whether or how CPIV3 antagonizes type I IFN antiviral effects have not yet been characterized. This study observed that CPIV3 was resistant to IFN-α treatment and antagonized IFN-α antiviral responses on MDBK and goat tracheal epithelial (GTE) cell models. Western blot analysis showed that CPIV3 infection reduced STAT1 expression and phosphorylation, which inhibited IFN-α signal transduction on GTE cells. By screening and utilizing specific monoclonal antibodies (mAbs), three CPIV3 accessory proteins C, V and D were identified during the virus infection process on the GTE cell models. Accessory proteins C and V, but not protein D, was identified to antagonize IFN-α antiviral signaling. Furthermore, accessory protein C, but not protein V, reduced the level of IFN-α driven phosphorylated STAT1 (pSTAT1), and then inhibit STAT1 signaling. Genetic variation analysis to the PIV3 accessory protein C has found two highly variable regions (VR), with VR2 (31-70th aa) being involved in for the CPIV3 accessory protein C to hijack the STAT1 signaling activation. The above data indicated that CPIV3 is capable of inhibiting IFN-α signal transduction by reducing STAT1 expression and activation, and that the accessory protein C, plays vital roles in the immune escape process.

Exogenous hydrogen sulfide inhibits apoptosis by regulating endoplasmic reticulum stress-autophagy axis and improves myocardial reconstruction after acute myocardial infarction.

During acute myocardial infarction, endoplasmic reticulum (ER) stress-induced autophagy and apoptosis have been shown as important pathogeneses of myocardial reconstruction. Importantly, hydrogen sulfide (H2S), as a third endogenous gas signaling molecule, exerts strong cytoprotective effect on anti-ER stress, autophagy regulation and antiapoptosis. Here, we showed that H2S treatment inhibits apoptosis by regulating ER stress-autophagy axis and improves myocardial reconstruction after acute myocardial infarction. We found that H2S intervention improved left ventricle function, reduced glycogen deposition in myocardial tissue mesenchyme, and inhibited apoptosis. Moreover, the expressions of fibrosis indicators (Col3a1 and Col1a2), ER stress-related proteins (CHOP and BIP/ERP78), autophagy-related proteins (Beclin and ATG5), apoptosis protein (Bax), as well as fibrosis protein Col4a3bp were all decreased after treatment with H2S. H2S administration also maintained MMP/TIMP balance. Mechanistically, H2S activated the PI3K/AKT signaling pathway. In addition, H2S treatment also reduced the expressions of ER stress-related proteins, autophagy-related proteins, and apoptins in in vitro experiments. Interestingly, activation of ER stress-autophagy axis could reverse the inhibitory effect of H2S on myocardial apoptosis. Altogether, these results suggested that exogenous H2S suppresses myocardial apoptosis by blocking ER stress-autophagy axis, which in turn reverses cardiac remodeling after myocardial infarction.

Bta-miR-98 Suppresses Replication of Caprine Parainfluenza Virus Type 3 Through Inhibiting Apoptosis by Targeting Caspase-3.

Caprine parainfluenza virus type 3 (CPIV3) is an emerging respiratory pathogen that affects the sheep and goat industry in China and possibly other countries around the world. Accumulating evidence suggests that microRNAs play important roles in regulating virus-host interactions and can suppress or facilitate viral replication. In this study, we showed that CPIV3 infection induced apoptosis in Madin-Darby bovine kidney (MDBK) cells, as determined by morphological changes and flow cytometry. Caspase activity and the expression of pro-apoptotic genes further indicated that CPIV3 induced apoptosis by activating both the intrinsic and extrinsic pathways. We also demonstrated the involvement of bta-microRNA-98 (bta-miR-98) in regulating CPIV3-induced apoptosis. Bta-miR-98 was downregulated in MDBK cells infected with CPIV3. Overexpression of bta-miR-98 significantly decreased the activities of caspase-3, -8, and -9. Conversely, inhibition of bta-miR-98 had completely opposite effects. Furthermore, our data showed that bta-miR-98 markedly affected CPIV3 replication by regulating apoptosis. Importantly, we found that bta-miR-98 modulated CPIV3-induced apoptosis by targeting caspase-3, an effector of apoptosis. Collectively, our results may suggest that CPIV3 infection induced apoptosis and downregulated the levels of bta-miR-98, and this miRNA regulated viral replication through effected apoptosis. This study contributes to our understanding of the molecular mechanisms underlying CPIV3 pathogenesis.

Exogenous Hydrogen Sulfide Ameliorates Diabetic Myocardial Fibrosis by Inhibiting Cell Aging Through SIRT6/AMPK Autophagy.

Stress aging of myocardial cells participates in the mechanism of myocardial fibrosis (MF). Previous studies have shown that hydrogen sulfide (H2S) can improve MF, however the specific internal mechanism remains still unclear. Therefore, this study aims to explore whether H2S can improve myocardial cell aging induced by high glucose and myocardial fibrosis in diabetic rats by activating autophagy through SIRT6/AMPK. We observed that HG (high glucose, 33 mM) induced down-regulation of endogenous H2S-producing enzyme CSE protein expression, increased cell senescence, down-regulation of autophagy-related proteins Beclin1, Atg5, Atg12, Atg16L1, and inhibition of SIRT6/AMPK signaling pathway in H9c2 cardiomyocytes. H2S (NaHS: 400 µM) could up-regulate CSE protein expression, inhibit cell senescence, activate autophagy and SIRT6/AMPK signaling pathway. On the contrary, no above phenomena was achieved upon addition of CSE inhibitor PAG (dl-propargylglycine: mmol/L). In order to further elucidate the relationship between H2S and SIRT6/AMPK signaling pathway, dorsomorphin dihydrochloride (Dor), an inhibitor of AMPK signaling pathway, was added to observe the reversal of H2S's inhibitory effect on myocardial cell aging. At the same, streptozotocin (STZ; 40 mg/kg) was injected intraperitoneally to build an animal model of diabetic SD rats. The results showed that myocardial collagen fibers were significantly deposited, myocardial tissue senescent cells were significantly increased and the expression of CSE protein was down-regulated, while SIRT6/AMPK signaling pathway and cell autophagy were significantly inhibited. H2S-treated (NaHS; 56 µmol/kg) could significantly reverse the above phenomenon. In conclusion, these findings suggest that exogenous H2S can inhibit myocardial cell senescence and improve diabetic myocardial fibrosis by activating CSE and autophagy through SIRT6/AMPK signaling pathway.