Injection of Matrix Metalloproteinase-9 Leads to Ventricular Remodeling.

Objective: Previous studies have found that some ventricular remodeling is accompanied by increased matrix metalloproteinase-9 (MMP-9) in vivo, and MMP-9 inhibitors can reduce ventricular remodeling. However, there is still no direct evidence that MMP-9 causes ventricular remodeling. In this study, MMP-9 was injected into rats to observe whether MMP-9 caused ventricular remodeling, thereby providing direct evidence of MMP-9-induced ventricular remodeling. Methods: Forty-eight eight-week-old male Wistar rats were randomly divided, by weight, into control, low-, medium-, and high-dose MMP-9 groups and were administered normal saline or recombinant rat MMP-9 0.7, 1.4, or 2.1 ng/g, respectively, via intraperitoneal injection, twice per week. On the 28th day, six rats were randomly selected from each group (Stage I). The remaining rats continued receiving injections until the 56th day (Stage II). Echocardiography was performed to observe cardiac structure and function, and the left ventricular mass index (LVWI) was calculated. Myocardial pathological changes and the collagen volume fraction (CVF) were observed by HE and VG staining in myocardial tissue. MMP-9 levels in serum were tested using ELISA. Myocardial MMP-9 levels were measured using Western blots, and the myocardial expression levels of MMP-9 mRNA were assessed using RT-PCR. Results: During Stage I, serum MMP-9 and myocardial MMP-9 mRNA levels are increased; hypertrophic cardiomyocytes, disorderly arrangement of fibers, and endochylema dissolution are observed in the medium- and high-dose groups. The left ventricular weight index (LVWI) and myocardial MMP-9 increased, and the collagen volume fraction (CVF) reduced in the high-dose group. In Stage II, the left ventricular end-diastolic volume (LVEDV) and diameter (LVIDd) are higher, and CVF decreased in the medium- and high-dose groups. Myocardial pathological lesions intensified. Serum MMP-9 in the model groups and myocardial MMP-9 in the medium- and high-dose groups are increased. Conclusions: Injection of MMP-9 can lead to ventricular remodeling.

Ox-LDL Aggravates the Oxidative Stress and Inflammatory Responses of THP-1 Macrophages by Reducing the Inhibition Effect of miR-491-5p on MMP-9.

Background: Oxidized low-density lipoprotein (ox-LDL) can induce oxidative stress and inflammatory responses in macrophages to facilitate the genesis and development of atherosclerosis. However, the intermediate links remain unclear. MiR-491-5P can inhibit matrix metalloproteinase 9 (MMP-9); however, it remains unclear whether ox-LDL enhances MMP-9 expression and aggravates the oxidative stress and inflammatory responses under the mediating effect of miR-491-5P. Method: THP-1 macrophages were divided into 10 groups: blank (control), model (ox-LDL), miR-491-5P high-expression (miR-491-5P mimic), miR-491-5P control (mimic-NC), MMP-9 high-expression (MMP-9-plasmid), MMP-9 control (plasmid-NC), miR-491-5P+plasmid-NC, miR-491-5P+ MMP-9-plasmid, MMP-9 gene silencing (MMP-9-siRNA), and gene silencing control (siRNA-NC). The cells were transfected for 48 h and then treated with 50 µg/mL of ox-LDL for 24 h. MMP-9 mRNA and miR-491-5P expression levels in the cells were detected using reverse transcription-quantitative polymerase chain reaction, and the MMP-9 levels were detected with western blotting. The levels of oxidative stress factors (malondialdehyde [MDA]), reactive oxygen species (ROS), and antioxidant factors (superoxide dismutase [SOD]), and the expression levels of inflammatory factors (tumor necrosis factor [TNF-α] and interleukin-1ß and-6 [IL-1ß and IL-6]) in the supernatant were detected with enzyme-linked immunosorbent assay. Results: MDA, ROS, TNF-α, IL-1ß, IL-6, and MMP-9 levels were increased, SOD activity was reduced, and miR-491-5P expression was downregulated in the ox-LDL group compared to the control group. In the miR-491-5P mimic group, the MDA, ROS, TNF-α, IL-1ß, IL-6, MMP-9 mRNA and protein levels were downregulated, and SOD activity was enhanced compared to the ox-LDL group. MMP-9-plasmid elevated the MDA, ROS, TNF-α, IL-1ß, IL-6, MMP-9 mRNA and protein levels, and downregulated SOD activity and miR-491-5P expression. Following transfection with MMP-9-siRNA, the MMP-9-plasmid outcomes were nullified, and the resulting trends were similar to the miR-491-5p simulation group. Oxidative stress and inflammatory responses were higher in the miR-491-5P mimic+MMP-9-plasmid co-transfection group than in the miR-491-5P mimic group. Conclusion: Ox-LDL aggravates the oxidative stress and inflammatory responses of THP-1 macrophages by reducing the inhibition effect of miR-491-5p on MMP-9.

The Efficacy and Safety of Chinese Medicine Fufang Zhenzhu Tiaozhi Capsule (FTZ) in the Treatment of Diabetic Coronary Heart Disease: Study Protocol for Multicenter, Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

BACKGROUND: Diabetic coronary heart disease (DCHD), the main macrovascular complication of type 2 diabetes mellitus (T2DM), is greatly harmful to T2DM patients. Traditional Chinese medicine (TCM) is an alternative and effective therapy to delay the development of macrovascular diseases, but the existing evidence of its efficacy and safety is insufficient. The aim of this multicenter, randomized, double-blind, placebo-controlled trial is to evaluate the efficacy and safety of Chinese Medicine Fufang Zhenzhu Tiaozhi capsule (FTZ) in treating DCHD. PATIENTS AND METHODS: This study includes a 2-week run-in, 52-week treatment, and 52-week post-treatment follow-up. A total of 160 participants will be recruited and randomized into two groups. The treatment group will receive FTZ and basic treatment, while the control group will receive the placebo and basic treatment. The primary outcome is the combined outcome including the major adverse cardiovascular events, coronary restenosis, and unplanned revascularization. The combined secondary outcomes include all-cause mortality, acute coronary syndrome, ischemic stroke, heart failure, unplanned re-hospitalization mainly caused by acute complications of diabetes, other thromboembolic events, and TCM symptom indicators. The safety outcomes and adverse events will also be evaluated in this trial. DISCUSSION: This trial evaluates the clinical effectiveness and safety of FTZ in patients with DCHD. The results are important to further explore the effectiveness of the comprehensive strategy "Tiao Gan Qi Shu Hua Zhuo" (modulating Gan, trigging key metabolic system to resolve pathogenic factors such as phlegm retention and dampness) in the prevention and control of glucolipid metabolic disorders (GLMD) including DCHD and T2DM. On the other hand, this study is the first trial of FTZ to observe cardiovascular outcomes through long-term follow-up after treatment of DCHD, which is of great value. TRIAL REGISTRATION: This trial was registered in the Chinese Clinical Trial Registry on April 07, 2019 (No. ChiCTR1900022345).

Development of a novel nanoflow liquid chromatography-parallel reaction monitoring mass spectrometry-based method for quantification of angiotensin peptides in HUVEC cultures.

BACKGROUND: This study aimed to develop an analytical method using liquid chromatography tandem mass spectrometry (LC-MS/MS) for the determination of angiotensin (Ang) I, Ang (1-9), Ang II, Ang (1-7), Ang (1-5), Ang III, Ang IV in human umbilical vein endothelial cell (HUVEC) culture supernatant. METHODS: HUVEC culture supernatant was added with gradient concentrations (0.05-1,000 ng/ml) of standard solutions of the Ang peptides. These samples underwent C18 solid-phase extraction and separation using a preconcentration nano-liquid chromatography mass spectrometry system. The target peptides were detected by a Q Exactive quadrupole orbitrap high-resolution mass spectrometer in the parallel reaction monitoring mode. Ang converting enzyme (ACE) in HUVECs was silenced to examine Ang I metabolism. RESULTS: The limit of detection was 0.1 pg for Ang II and Ang III, and 0.5 pg for Ang (1-9), Ang (1-7), and Ang (1-5). The linear detection range was 0.1-2,000 pg (0.05-1,000 ng/ml) for Ang II and Ang III, and 0.5-2,000 pg (0.25-1,000 ng/ml) for Ang (1-9) and Ang (1-5). Intra-day and inter-day precisions (relative standard deviation) were <10%. Ang II, Ang III, Ang IV, and Ang (1-5) were positively correlated with ACE expression by HUVECs, while Ang I, Ang (1-7), and Ang (1-9) were negatively correlated. CONCLUSION: The nanoflow liquid chromatography-parallel reaction monitoring mass spectrometry-based methodology established in this study can evaluate the Ang peptides simultaneously in HUVEC culture supernatant.

A single-center observational study on the efficacy of percutaneous coronary intervention for ischemic heart failure: A cohort study.

The effects of revascularization by percutaneous coronary intervention (PCI) on cardiac function and clinical outcomes in patients with confirmed coronary artery disease (CAD) and heart failure (HF), on the basis of the optimal medical treatment recommended by current guidelines, remain to be determined.A cohort study was performed to evaluate the efficacy of PCI on the basis of optimal medical treatment in patients with CAD and HF. Patients who received PCI were subsequently grouped according to partial and complete revascularization (CR) depending on the PCI outcome. The primary outcome was defined as a composite outcome of major adverse cardiovascular events (MACEs). Changes in left ventricular ejection fraction (LVEF) also were compared.A total of 69 patients (12 who received medical treatment and 57 who received PCI) were included. Patients in the PCI group showed significantly improved LVEF (P < .001), but patients in the medical treatment group did not (P > .05) after 3 months of follow-up. MACEs occurred in 50% patients in the medical treatment group and 19.3% patients of the PCI group, with this difference almost reaching statistical significance (P = .06). Compared with patients who received medical therapy only, patients who received PCI experienced better survival (P = .02). Moreover, survival seemed to be better in patients who achieved CR with PCI of the coronary arteries than in those who had partial revascularization of the coronary arteries (P = .06).PCI may be effective for improving survival in patients with CAD and HF.

The CD147/MMP-2 signaling pathway may regulate early stage cardiac remodelling in spontaneously hypertensive rats.

Previous studies have reported that decreased matrix metalloproteinase-2 (MMP-2) is associated with early stage (age 8-16 weeks) ventricular remodelling in spontaneously hypertensive rats (SHR). We hypothesized that inhibited CD147/MMP-2 signalling might down-regulate MMP-2 expression and augment remodelling in spontaneously hypertensive rats. Twenty-nine male SHR (8 weeks) were randomly assigned to SHR, CD147, and CD147+DOX groups. The control group included eight age-matched WKY rats. CD147 and CD147+DOX groups received recombinant human CD147 (600 ng/kg in 1.5 mL saline, weekly). The SHR and WKY groups received the vehicle. The CD147+DOX group also received doxycycline, an inhibitor of MMPs (daily, 30 mg/kg in 1.5 mL saline, iG). On day 56 echocardiography and left ventricular mass index (LVWI) measurements were collected and histological sections were stained for cell and collagen content. Myocardium MMP-2, TIMP-1, CD147, and collagens types I and III were estimated by western blot. CD147 and the ratio of MMP-2/TIMP-1 were lower in SHR than WKY rats (P<.05). Myocyte hypertrophy, partial fibre breaks, plasmolysis, necrosis and collagen content (collagen volume fraction [CVF], I and III) in SHR were above control levels (P<.05). CD147 rats showed CD147, MMP-2 and MMP-2/TIMP-1 were increased (P<.05), CVF, LVWI, and collagen I and III were decreased (P<.05) and myocyte morphology was improved. CD147 levels did not differ between CD147+DOX and CD147 groups, CVF, collagens type I and III and partial fiber breaks were more abundant in CD147+DOX (P<.05). In summary, an inhibited CD147/MMP-2 pathway was associated with early stage cardiac remodelling, and CD147 supplementation may attenuate this response.

[Clinical applications of active fixation at the right ventricular outflow tract using a modified pacing leads model].

OBJECTIVE: To assess the feasibility and safety of using the modified active fixation pacing leads model to pace the right ventricular outflow tract septum. METHODS: A total of 136 patients undergoing artificial heart pacemaker implantation with active fixation pacing leads were randomized into two groups to receive conventional right ventricular outflow tract pacing (CRVOTP) or modified right ventricular outflow tract pacing (MRVOTP). The electrode lead wire core was modeled in a double-curved three-dimensional shape in CRVOTP group and in a J-shaped bend in MRVOTP group before fixation at the right ventricular outflow tract septum. RESULTS: Right ventricular outflow tract septum pacing was achieved successfully in all the patients. None of patients experienced serious complications. No significant differences were found between the two groups in the number of times of electrode fixation, pacing thresholds, impedance, R wave height or QRS wave width during the operation, but MRVOTP was associated with a reduced time of X -ray exposure and operation (P<0.05) due to the convenience in electrode modeling and in passing the leads through the tricuspid annulus and the direct access to the right ventricular outflow tract septum. Postoperative follow-up of the patients showed no incidence of active fixation pacing lead dislocation and comparable pacing thresholds of the ventricular electrodes, impedance, R wave height and QRS wave width between the two groups. CONCLUTIONS: Using the modified active fixation pacing leads model to pace the right ventricular outflow tract septum can reduce the time of X -ray exposure and operation with a low probability of lead damage.

[Therapeutic effect of deoxyribonucleotidum on acute viral myocarditis].

OBJECTIVE: To evaluate the therapeutic efficacy of deoxyribonucleotidum in treatment of acute viral myocarditis. METHODS: Eighty-eight patients with acute viral myocarditis were randomized equally into therapeutic group and control group. Patients in the control group were treated with routine treatment and those in the therapeutic group were given deoxyribonucleotidum in addition to routine treatment. After 4 weeks, the total efficacy rate and median time of symptom disappearance were compared between the two groups. RESULTS: The total efficacy rate in the control and therapeutic groups was 79.54% and 95.45% (P=0.049), and the median time of symptom disappearance was 9.5 days and 6.5 days, respectively (P=0.035). Hypotension and mild dizziness were found in 2 patients in the therapeutic group without other severe side effects. CONCLUSION: Deoxyribonucleotidum can improve the therapeutic effect for acute viral myocarditis.

[Clinical significance of protein Z alteration in patients with cardio-cerebral thrombotic diseases].

OBJECTIVE: To study the alteration of protein Z (PZ) in patients with cardio-cerebral thrombotic diseases, its clinical significance and relations with FX. METHODS: PZ and FX:Ag were measured by ELISA, and plasma FX:C by first stage method. In 170 patients with acute ischemic stroke (AIS), 40 acute myocardial infarction (AMI) and 60 healthy adults as contrast, PZ, FX:C and FX:Ag were measured and compared between incipience and recurrence, different ages and genders. RESULTS: In AIS and AMI groups, PZ levels decreased significantly to (940.02 +/- 229.82) microg/L and (1071.44 +/- 180.52) microg/L, respectively \[the contrast group was (2257.97 +/- 479.76) microg/L, P < 0.001\]. But FX:C and FX:Ag raised to (136.73 +/- 34.93)% and (135.54 +/- 54.39)% in AIS group; and to (139.53 +/- 29.18)%, (129.75 +/- 21.91)% in AMI group, respectively, while in the contrast group they were (94.33 +/- 22.00)% and (77.22 +/- 13.19)% (P < 0.001). In the comparative research between the AIS group, AMI group and the contrast group, PZ level was clearly found to negatively relate to the level of FX:C and FX:Ag (P < 0.001). Meanwhile, PZ level, FX:C and FX:Ag in recur-AIS group and recur-AMI group exhibited significant differences (P < 0.05) from those in the primary AIS and AMI groups, suggesting that the decrease of PZ levels reflected the pathological process of the disease. In addition, PZ level gradually decreased with the increase of age (P < 0.05), while FX:C and FX:Ag had no relations with age (P > 0.05). No correlation was found in sex with PZ level, FX:C, FX:Ag (P > 0.05). CONCLUSION: PZ level was significantly decreased in AIS and AMI patients and was negatively related to FX:C and FX:Ag. The mechanism leading to FX increase may partially related with the decreased of PZ. PZ level was different in the primary and recurrent disease and was gradually decreased with the increase of age. Lack of PZ might be a etiological factor of cardio-cerebral thrombotic diseases.