Chromatographic purification of the plasmin-like enzyme from clamworm (Perinereis aibuhitensis Grub) and its fibrinolytic activity by metal ions.

In this study, fibrinolytic protease was isolated and purified from Perinereis aibuhitensis Grub, and the extraction process was optimized. The properties of the enzyme, such as the amino acid composition, thermal stability, optimal temperature, and pH, were investigated. After detoxification, proteins collected from fresh Clamworm (Perinereis aibuhitensis Grub) were concentrated via ammonium sulfate precipitation. The crude protease was purified using gel filtration resin (Sephadex G-100), anion exchange resin (DEAE-Sepharose FF), and hydrophobic resin (Phenyl Sepharose 6FF). The molecular weight of the protease was determined by polyacrylamide gel electrophoresis (SDS-PAGE). The optimum temperature and optimum pH of the protease were determined. The activity of crude protease in the 40-60% salt-out section was the highest, reaching 467.53 U/mg. The optimal process for purifying crude protein involved the application of DEAE-Sepharose FF and Phenyl Sepharose 6FF, which resulted in the isolation of a single protease known as Asp60-D1-P1 with the highest fibrinolytic activity; additionally, the enzyme activity was measured at 3367.76 U/mg. Analysis by Native-PAGE and SDS-PAGE revealed that the molecular weight of Asp60-D1-P1 was 44.5 kDa, which consisted of two subunits with molecular weights of 6.5 and 37.8 kDa, respectively. The optimum temperature for Asp60-D1-P1 was 40°C, and the optimal pH was 8.0.

Extracellular vesicles secreted by bone marrow stem cells mediate angiogenesis for the treatment of diabetic ulcers: A systematic review and meta-analysis of preclinical studies.

Background: Diabetic ulcers (DUs) typically occur in patients with vascular diseases and diabetes. Extracellular vesicles secreted by bone marrow-derived stem cells (BMSC-EVs) represent a cell-free therapy that has emerged as a promising alternative for treating DU, especially due to significant advancements in the understanding of their role in promoting angiogenesis; however, their application in DU treatment remains in the preclinical stage, and their effectiveness is still uncertain. Therefore, we conducted this meta-analysis to evaluate the therapeutic efficacy of BMSC-EVs in treating DU and to expedite the clinical translation of BMSC-EV therapy for DU. Methods: We conducted a comprehensive search of PubMed, Cochrane Library, MEDLINE, EMBASE, China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Database, and our self-constructed database of Chinese Biomedical Literature up to May 2023 to identify preclinical studies related to the therapeutic use of extracellular vesicles secreted by bone marrow-derived stem cells for treating diabetic ulcers. Outcome measures included wound healing rate, neovascularization density, a-sma, and CD31. RevMan 5 software was employed for all statistical analyses. Results: In this meta-analysis, a total of 11 studies involving 103 animals were identified. The pooled analysis indicated that BMSC-EV treatment showed a superior wound healing rate compared to that of the control group (SMD = 1.06, 95% CI [0.52, 1.60], P = 0.0001). In the subgroup analysis, EV combined with new materials or drug therapy performed better than the sole injection of extracellular vesicles (SMD = 1.85, 95% CI [0.87, 2.82], P < 0.00001). BMSC-EV treatment also resulted in a higher number of neovascular structures compared to the control group(SMD = 5.80, 95% CI[0.89,10.71], P = 0.006). In the subgroup analysis, EV combined therapy showed a significant difference in the number of blood vessels compared to the sole injection of extracellular vesicles (SMD = 4.90, 95% CI[2.64,7.15], P < 0.00001). However, BMSCs-EV treatment did not demonstrate any statistically significant difference in the angiogenesis-related indicators CD31 and α-SMA compared to the control group (SMD = 1.61, 95% CI[-0.51,3.74], P = 0.14). Conclusion: According to the current meta-analysis, BMSC-EV therapy can enhance the healing of diabetic ulcers and promote wound angiogenesis, particularly when used in combination with novel dressings or other drugs, which further accelerates the healing process of diabetic ulcers. To establish the most effective parameters for EV treatment in diabetic ulcers, future research should promptly progress into clinical trials.

Effect of miR-499-5p/SOX6 axis on atrial fibrosis in rats with atrial fibrillation.

Atrial fibrosis is involved in the progression of atrial fibrillation (AF). miR-499-5p is the most downregulated microRNA in arrhythmogenic cardiomyopathy hearts. Sry-related high-mobility-group box 6 (SOX6) is associated with apoptosis, inflammatory responses, and fibrosis. This study investigated the mechanism of miR-499-5p in ameliorating AF rats by regulating SOX6. AF rat models were established by injecting Ach-CaCl2 mixture, and the rats were treated with Lv-miR-499-5p/oe-SOX6/si-SOX6 before modeling. AF duration was recorded using electrocardiogram. miR-499-5p and SOX6 expression levels in the myocardium were determined by reverse transcription-quantitative polymerase chain reaction. The binding of miR-499-5p and SOX6 was validated. The atrial fibrosis degree and cardiomyocyte apoptosis were assessed using the Masson and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining methods. Levels of SOX6, atrial fibrosis markers (collage I/α-SMA/TGFß1), cell cycle-related proteins (p21/CDC25/Cyclin B1), and cell senescence markers (SA-ß-gal/γ-H2AX) were measured using Western blotting and immunohistochemistry. miR-499-5p was downregulated and SOX6 was upregulated in AF rats. miR-499-5p overexpression shortened the AF duration, alleviated atrial fibrosis, and decreased collage I/α-SMA/TGFß1. miR-499-5p targeted SOX6 to ameliorate atrial fibrosis. AF rats exhibited increased p21/CDC25/Cyclin B1/SA-ß-gal/γ-H2AX levels and raised cardiomyocyte apoptosis. SOX6 silencing downregulated p21 and alleviated cardiomyocyte cycle arrest, cell senescence, and apoptosis in AF rats. Shortly, miR-499-5p suppresses atrial fibrosis and cardiomyocyte senescence by targeting SOX6 and downregulating p21, thus mitigating AF in rats.

Quantitative PCR of string-test collected gastric material: A feasible approach to detect Helicobacter pylori and its resistance against clarithromycin and levofloxacin for susceptibility-guided therapy.

BACKGROUND: As the reduced eradication rate of Helicobacter pylori (H. pylori), we introduced string-test and quantitative PCR (qPCR) for susceptibility-guided therapy innovatively. The practicality of the string test was evaluated. METHODS: It was an open-label, non-randomized, parallel, single-center study, in which subjects tested by 13 C- urea breath test (UBT) and string-qPCR were enrolled. Based on the results of string-qPCR, we calculated clarithromycin and levofloxacin resistance rates and gave 13 C-UBT positive patients 14 days susceptibility-guided bismuth quadruple therapy. In the empirical therapy group, we retrospectively analyzed the treatment results of 13 C-UBT positive patients also treated with bismuth quadruple at Shenzhen Luohu People's Hospital from January 2021 to May 2022. The eradication rate was compared between susceptibility-guided therapy and empirical therapy groups. RESULTS: The diagnosis of H. pylori infection using the string-qPCR had an overall concordance rate of 95.9% with the 13 C-UBT results. Based on the results of string-qPCR, the clarithromycin and levofloxacin resistance rates were 26.1% and 31.8%, respectively. The patients who were given 14 days susceptibility-guided bismuth-based quadruple therapy achieved a high H. pylori eradication rate of 91.8%. Retrospective analysis of patient treatment data from January 2021 to May 2022 available in the hospital database revealed an overall success rate of 82.3% for those who received empirical bismuth-based quadruple therapies, which is marginally significantly lower than that of the string-qPCR susceptibility-guided group (p = 0.084). CONCLUSION: The high treatment success rate of 91.8% indicates that the string-qPCR test is a valuable and feasible approach for clinical practice to help improve H. pylori treatment success rate.

HDAC3 Impairs Cardiac Function in Chronic Heart Failure Rats via Mediating MicroRNA-26b-3p to Target High Mobility Group AT-Hook 2.

BACKGROUND: Histone deacetylase 3 (HDAC3) has been studied in chronic heart failure (CHF), while the regulatory mechanism of HDAC3 on the development of CHF in regulating microRNA (miR)-26b-3p/high mobility group AT-hook 2 (HMGA2) axis has not been extensively investigated. This study aimed to probe the effects of HDAC3, miR-26b-3p and HMGA2 on CHF. METHODS: CHF rat models were established using aortic coarctation. HDAC3, miR-26b-3p and HMGA2 levels in CHF rats were examined. Thereafter, the CHF rats were injected with relative oligonucleotides and plasmids of HDAC3, miR-26b-3p and HMGA2 to detect the cardiac function, inflammatory reaction, myocardial tissue pathological changes, and cardiomyocyte apoptosis. The binding relationship between miR-26b-3p and HMGA2 and the interaction between HDAC3 and miR-26b-3p were validated. RESULTS: HDAC3 and HMGA2 were elevated, while miR-26b-3p was decreased in CHF rats. The reduced HDAC3 or HMGA2 or enriched miR-26b-3p attenuated cardiac dysfunction, inflammatory reaction, myocardial tissue pathological changes and cardiomyocyte apoptosis in CHF rats, while the reduction of miR-26b-3p exerted the opposite effects. Furthermore, the inhibition of the miR-26b-3p or elevation of HMGA2 reversed the effect of reduced HDAC3 on mitigating CHF progression. Mechanically, miR-26b-3p targeted HMGA2 and HDAC3 bound to miR-26-3p. CONCLUSION: Downregulation of HDAC3 relieves cardiac function in CHF rats via mediating miR-26b-3p/HMGA2 axis. This study provides novel theory references and a distinct direction for the therapy strategies of CHF.

Dysgonomonas mossii Strain Shenzhen WH 0221, a New Member of the Genus Dysgonomonas Isolated from the Blood of a Patient with Diabetic Nephropathy, Exhibits Multiple Antibiotic Resistance.

Herein, we present a new bacterial strain isolated from infected blood of a patient with diabetic nephropathy. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry failed to identify the strain. 16S rRNA gene sequencing showed the highest similarity (>99.5%) with genus Dysgonomonas, but the strain could not be distinguished from Dysgonomonas oryzarvi and Dysgonomonas mossii. Whole genome sequencing, followed by phylogenetic analysis and average nucleotide identity (>95%) analysis, confirmed that the new strain represented Dysgonomonas mossii, leading it to be named Dysgonomonas mossii strain Shenzhen WH 0221. Shenzhen WH 0221 was 3.60 Mb with 37.4% GC content. It was Gram-stain negative, facultatively anaerobic, and grown on Columbia agar supplemented with 5% of sheep blood, exhibiting a smooth surface and pinpoint morphology. The morphological characteristics of this strain include a short rod shape without flagella and a size of 0.45-0.55 × 0.95-1.52 µm observed under transmission electron microscopy. The physiological and biochemical features and major cellular fatty acids (characterized by C14:0 3-OH, C14:0 9-CH3, and C16:0) differed from D. mossii CCUG 43457T and other members of the genus Dysgonomonas. The isolate was found resistant to most cephalosporins, penicillin, norfloxacin, vancomycin, and chloramphenicol, but was susceptible to meropenem, imipenem, tetracycline, clindamycin, and amoxicillin-clavulanic acid. Genes kdpE, ykkD, cmeB, TLA-3, and vanRM found in its genome are probably associated with multiple antibiotic resistance. Lipopolysaccharides, capsules, and cytolysin may also help to illuminate its potential pathogenicity. This is the first report of a case of sepsis caused by Dysgonomonas mossii, and its pathogenic system was analyzed by whole genome sequencing. IMPORTANCE This study identified a new strain, Dysgonomonas mossii strain Shenzhen WH 0221, which has been first reported to cause sepsis isolated from infected blood of a patient with diabetic nephropathy. Physiological and biochemical characterizations, as well as overall fatty acid profile, distinguish Shenzhen WH 0221 from other species of the same genus. However, limited antibiotics were researched for Dysgonomonas mossii. Seventeen antibiotics spanning at least 6 classes were studied, providing a valuable guide to the clinical usage of drugs to treat Dysgonomonas mossii infection. For the first time, we report genome-based functional predictions for Dysgonomonas mossii. Five antibiotic resistance ontologies and more than 200 virulence factors likely underlie the multidrug resistance of Shenzhen WH 0221 and its potential pathogenicity.

miR-29b ameliorates atrial fibrosis in rats with atrial fibrillation by targeting TGFßRΙ and inhibiting the activation of Smad-2/3 pathway.

OBJECTIVE: Atrial fibrillation (AF) is a major cause of stroke with lifetime risks. microRNAs (miRNAs) are associated with AF attenuation, yet the mechanism remains unknown. This study investigated the functional mechanism of miR-29b in atrial fibrosis in AF. METHODS: The AF rat model was established by a 7-day intravenous injection of Ach-CaCl2 mixture. AF rats were injected with adeno-associated virus (AAv)-miR-29b and TGFßRΙ overexpression plasmid. AF duration was recorded by electrocardiogram. Atrial fibrosis was observed by Masson staining. Expressions of COL1A1, COL3A1, TGFßRΙ, TGFßΙ, miR-29b and Smad-2/3 pathway-related proteins in atrial tissues were detected by RT-qPCR and Western blot. Binding sites of miR-29b and TGFßRΙ were predicted and their target relationship was verified by dual-luciferase reporter assay. RESULTS: miR-29b was poorly expressed and expressions of COL1A1, COL3A1, TGFßRΙ, and TGFß1 were increased in atrial tissues of AF rats. miR-29b overexpression alleviated atrial fibrosis, reduced expressions of COL1A1, COL3A1, and TGFß1, and shortened AF duration in AF rats. TGFßRΙ was highly expressed in atrial tissues of AF rats. miR-29b targeted TGFßRΙ. TGFßRΙ overexpression overcame the improving effect of miR-29b overexpression on AF. miR-29b overexpression decreased ratios of p-Smad-2/3 and Smad-2/3 and inhibited the Smad-2/3 pathway. CONCLUSION: miR-29b might mitigate atrial fibrosis in AF rats by targeting TGFßRΙ and inhibiting the Smad-2/3 pathway.

Hyperbaric Oxygen Preconditioning Protects Against Cerebral Ischemia/Reperfusion Injury by Inhibiting Mitochondrial Apoptosis and Energy Metabolism Disturbance.

Hyperbaric oxygen (HBO) therapy is considered a safe and feasible method that to provide neuroprotection against ischemic stroke. However, the therapy mechanisms of HBO have not been fully elucidated. We hypothesized that the mechanism underlying the protective effect of HBO preconditioning (HBO-PC) against cerebral ischemia/reperfusion injury was related to inhibition of mitochondrial apoptosis and energy metabolism disorder. To test this hypothesis, an ischemic stroke model was established by middle cerebral artery occlusion (MCAO) in rats. HBO-PC involved five consecutive days of pretreatment before MCAO. In additional experiments, X chromosome-linked inhibitor of apoptosis protein (XIAP) and second mitochondria-derived activator of caspases (SMAC) shRNA and NC plasmids were intraventricularly injected into rat brains after MCAO (2 h). After 24 h, all rats underwent motor function evaluation, which was assessed by modified Garcia scores. TTC staining for the cerebral infarct and cerebral edema, and TUNEL staining for cell apoptosis, were also analyzed. Reactive oxygen species and antioxidative enzymes in rat brains were detected, as well as mitochondrial complex enzyme activities, ATP levels, and Na+/K+ ATPase activity. Western blot was used to detect apoptotic proteins including Bcl-2, Bax, caspase-3, caspase-9, cyc-c, XIAP, and SMAC. HBO-PC remarkably reduced the infarct volume and improved neurological deficits. Furthermore, HBO-PC alleviated oxidative stress and regulated the expression of apoptosis-related proteins. Moreover, HBO-PC inhibited the decrease in ATP levels, mitochondrial complex enzyme activities, and Na+/K+ ATPase activity to maintain stable energy metabolism. XIAP knockdown weakened the protective effect of HBO, whereas SMAC knockdown strengthened its protective effect. The effects of HBO-PC can be attributed to inhibition of ischemia/hypoxia-induced mitochondrial apoptosis and energy metabolism disturbance. The action of HBO-PC is related to the XIAP and SMAC signaling pathways.

Peroxisome proliferator-activated receptor γ attenuates serotonin-induced pulmonary artery smooth muscle cell proliferation and apoptosis inhibition involving ERK1/2 pathway.

Serotonin (5-HT) has been shown to be involved in pulmonary vascular remodeling in pulmonary arterial hypertension (PAH) by inducing pulmonary artery smooth muscle cells (PASMCs) proliferation and inhibiting PASMC apoptosis. Peroxisome proliferator-activated receptor γ (PPARγ) plays a crucial role in regulating proliferation and apoptosis of many cell types. Moreover, recently, loss of PPARγ has also been reported to be associated with the development of PAH. The present study is aimed to assess whether PPARγ is involved in 5-HT induced PASMC proliferation and apoptosis inhibition and the possible mechanism. We found that 5-HT could induce PASMC proliferation and inhibit PASMC apoptosis in a dose-dependent manner. Furthermore, we found that 5-HT negatively regulated PPARγ expression and gene promoter activity in PASMCs and 5-HT induced PASMC proliferation and apoptosis resistance could be abolished by PPARγ agonists and enhanced by PPARγ inhibitor. In addition, we found that extracellular signal-regulated kinase (ERK) signaling pathway mediated the 5-HT-induced inhibition of PPARγ expression. Our results might provide novel insights into the mechanisms for the pro-remodeling action of 5-HT in pulmonary vasculature.

Serum fibroblast growth factor 21 levels are increased in atrial fibrillation patients.

BACKGROUND: Fibroblast growth factor 21 (FGF-21), a newly discovered adipokine, plays an important role in glucose and lipid metabolism and is associated with the development of metabolic disorders, such as obesity, and cardiovascular diseases. This study aimed to investigate the association of serum FGF-21 levels with the presence of atrial fibrillation (AF). METHODS: Total 113 patients with AF and 60 healthy control subjects were enrolled. All AF cases were categorized into paroxysmal, persistent and permanent AF. Serum levels of FGF-21, high-sensitivity C-reactive protein (hs-CRP) and other routine biochemical parameters were measured. RESULTS: Serum FGF-21 levels were significantly higher in AF patients than in controls (250.12±78.48 vs. 144.15±56.31pg/mL, P<0.001), and hs-CRP levels were significantly higher in AF patients than in controls (2.36±1.10 vs. 1.24±0.82, P<0.05). In subgroup studies, patients with permanent AF had higher serum FGF-21 levels than those with persistent and paroxysmal AF. After the adjustment of the age, gender and body mass index, serum FGF-21 levels were positively correlated with left atrial diameter (LAD) (P<0.01). A multivariate logistic regression analysis showed that FGF-21, LAD and hs-CRP were correlated with AF (P<0.05). CONCLUSIONS: Our data demonstrate that serum FGF-21 levels are elevated in AF patients and associated with atrial remolding, independent of established risk factors such as C-reactive protein.

Serotonin drives the activation of pulmonary artery adventitial fibroblasts and TGF-ß1/Smad3-mediated fibrotic responses through 5-HT(2A) receptors.

Pulmonary arterial remodeling is characterized by excessive proliferation, migration, and pro-differentiation and fibrotic activation of adventitial fibroblasts in pulmonary arterial hypertension (PAH) process. Several lines of evidence indicate that serotonin (5-HT) plays a central role in the pathogenesis of pulmonary arterial remodeling. In the present study, we investigated whether 5-HT is directly involved in the functional regulation of pulmonary artery adventitial fibroblasts (PAFs). Incubation of cultured rat PAFs with 5-HT caused a dose-dependent stimulation of cell proliferation, migration activity, and a time-dependent increase of α-SMA expression, a marker of fibroblast differentiation into myofibroblasts, and adventitia fibrosis, evaluating connective tissue growth factor (CTGF) and extracellular matrix (ECM) mRNAs and proteins. These effects were attenuated by the 5-HT2A receptor antagonist, ketanserin and mimicked by the 5-HT2A receptor agonist DOI. 5-HT-induced fibroblasts phenotypic alterations and ECM accumulation were dependent on stimulation of transforming growth factor (TGF)-ß1 as demonstrated using a neutralizing antibody. 5-HT also caused Smad3 phosphorylation and ketanserin diminished 5-HT-induced Smad3 activation. These results demonstrated that 5-HT can directly activate PAFs through 5-HT2A receptor and promote fibroblasts phenotypic alterations and adventitia fibrosis depending on the signaling of the TGF-ß1/Smad3 pathway.