Hydrogen sulfide attenuates atherosclerosis induced by low shear stress by sulfhydrylating endothelium NFIL3 to restrain MEST mediated endothelial mesenchymal transformation.

BACKGROUND: Endothelial-mesenchymal transition (EndMT) induced by low shear stress plays an important role in the development of atherosclerosis. However, little is known about the correlation between hydrogen sulfide (H2S), a protective gaseous mediator in atherosclerosis and the process of EndMT. METHODS: We constructed a stable low-shear-stress-induced(2 dyn/cm2) EndMT model, acombined with the pretreatment method of hydrogen sulfide slow release agent(GYY4137). The level of MEST was detected in the common carotid artery of ApoE-/- mice with local carotid artery ligation. The effect of MEST on atherosclerosis development in vivo was verified using ApoE-/- mice were given tail-vein injection of endothelial-specific overexpressed and knock-down MEST adeno-associated virus (AAV). RESULTS: These findings confirmed that MEST is up-regulated in low-shear-stress-induced EndMT and atherosclerosis. In vivo experiments showed that MEST gene overexpression significantly promoted EndMT and aggravated the development of atherosclerotic plaques and MEST gene knockdown significantly inhibited EndMT and delayed the process of atherosclerosis. In vitro, H2S inhibits the expression of MEST and EndMT induced by low shear stress and inhibits EndMT induced by MEST overexpression. Knockdown of NFIL3 inhibit the up regulation of MEST and EndMT induced by low shear stress in HUVECs. CHIP-qPCR assay and Luciferase Reporter assay confirmed that NFIL3 binds to MEST DNA, increases its transcription and H2S inhibits the binding of NFIL3 and MEST DNA, weakening NFIL3's transcriptional promotion of MEST. Mechanistically, H2S increased the sulfhydrylation level of NFIL3, an important upstream transcription factors of MEST. In part, transcription factor NFIL3 restrain its binding to MEST DNA by sulfhydration. CONCLUSIONS: H2S negatively regulate the expression of MEST by sulfhydrylation of NFIL3, thereby inhibiting low-shear-stress-induced EndMT and atherosclerosis.

TM6SF2 reduces lipid accumulation in vascular smooth muscle cells by inhibiting LOX-1 and CD36 expression.

TM6SF2, predominantly expressed in the liver and intestine, is closely associated with lipid metabolism. We have demonstrated the presence of TM6SF2 in VSMCs within human atherosclerotic plaques. Subsequent functional studies were conducted to investigate its role in lipid uptake and accumulation in human vascular smooth muscle cells (HAVSMCs) using siRNA knockdown and overexpression techniques. Our results showed that TM6SF2 reduced lipid accumulation in oxLDL-stimulated VSMCs, likely through the regulation of lectin-like oxLDL receptor 1 (LOX-1) and scavenger receptor cluster of differentiation 36 (CD36) expression. We concluded that TM6SF2 plays a role in HAVSMC lipid metabolism with opposing effects on cellular lipid droplet content by downregulation of LOX-1 and CD36 expression.

PCSK9 (Proprotein Convertase Subtilisin/Kexin Type 9) Triggers Vascular Smooth Muscle Cell Senescence and Apoptosis: Implication of Its Direct Role in Degenerative Vascular Disease.

OBJECTIVE: PCSK9 (proprotein convertase subtilisin/kexin type 9) plays a critical role in cholesterol metabolism via the PCSK9-LDLR (low-density lipoprotein receptor) axis in the liver; however, evidence indicates that PCSK9 directly contributes to the pathogenesis of various diseases through mechanisms independent of its LDL-cholesterol regulation. The objective of this study was to determine how PCSK9 directly acts on vascular smooth muscle cells (SMCs), contributing to degenerative vascular disease. Approach and Results: We first examined the effects of PCSK9 on cultured human aortic SMCs. Overexpression of PCSK9 downregulated the expression of ApoER2 (apolipoprotein E receptor 2), a known target of PCSK9. Treatment with soluble recombinant human ApoER2 or the DNA synthesis inhibitor, hydroxyurea, inhibited PCSK9-induced polyploidization and other cellular responses of human SMCs. Treatment with antibodies against ApoER2 resulted in similar effects to those observed with PCSK9 overexpression. Inducible, SMC-specific knockout of Pcsk9 accelerated neointima formation in mouse carotid arteries and reduced age-related arterial stiffness. PCSK9 was expressed in SMCs of human atherosclerotic lesions and abundant in the "shoulder" regions of vulnerable atherosclerotic plaques. PCSK9 was also expressed in SMCs of abdominal aortic aneurysm, which was inversely related to the expression of smooth muscle α-actin. CONCLUSIONS: Our findings demonstrate that PCSK9 inhibits proliferation and induces polyploidization, senescence, and apoptosis, which may be relevant to various degenerative vascular diseases.

Effect of spermidine on ameliorating spermatogenic disorders in diabetic mice via regulating glycolysis pathway.

Diabetes mellitus (DM), a high incidence metabolic disease, is related to the impairment of male spermatogenic function. Spermidine (SPM), one of the biogenic amines, was identified from human seminal plasma and believed to have multiple pharmacological functions. However, there exists little evidence that reported SPM's effects on moderating diabetic male spermatogenic function. Thus, the objective of this study was to investigate the SPM's protective effects on testicular spermatogenic function in streptozotocin (STZ)-induced type 1 diabetic mice. Therefore, 40 mature male C57BL/6 J mice were divided into four main groups: the control group (n = 10), the diabetic group (n = 10), the 2.5 mg/kg SPM-treated diabetic group (n = 10) and the 5 mg/kg SPM-treated diabetic group (n = 10), which was given intraperitoneally for 8 weeks. The type 1 diabetic mice model was established by a single intraperitoneal injection of STZ 120 mg/kg. The results showed that, compare to the control group, the body and testis weight, as well the number of sperm were decreased, while the rate of sperm malformation was significantly increased in STZ-induced diabetic mice. Then the testicular morphology was observed, which showed that seminiferous tubule of testis were arranged in mess, the area and diameter of which was decreased, along with downregulated anti-apoptotic factor (Bcl-2) expression, and upregulated pro-apoptotic factor (Bax) expression in the testes. Furthermore, testicular genetic expression levels of Sertoli cells (SCs) markers (WT1, GATA4 and Vimentin) detected that the pathological changes aggravated observably, such as the severity of tubule degeneration increased. Compared to the saline-treated DM mice, SPM treatment markedly improved testicular function, with an increment in the body and testis weight as well as sperm count. Pro-apoptotic factor (Bax) was down-regulated expression with the up-regulated expression of Bcl-2 and suppression of apoptosis in the testes. What's more, expression of WT1, GATA4, Vimentin and the expressions of glycolytic rate-limiting enzyme genes (HK2, PKM2, LDHA) in diabetic testes were also upregulated by SPM supplement. The evidence derived from this study indicated that the SMP's positive effect on moderating spermatogenic disorder in T1DM mice's testis. This positive effect is delivered via promoting spermatogenic cell proliferation and participating in the glycolytic pathway's activation.

Physiology and role of PCSK9 in vascular disease: Potential impact of localized PCSK9 in vascular wall.

Proprotein convertase subtilisin/kexin type-9 (PCSK9), a member of the proprotein convertase family, is an important drug target because of its crucial role in lipid metabolism. Emerging evidence suggests a direct role of localized PCSK9 in the pathogenesis of vascular diseases. With this in our consideration, we reviewed PCSK9 physiology with respect to recent development and major studies (clinical and experimental) on PCSK9 functionality in vascular disease. PCSK9 upregulates low-density lipoprotein (LDL)-cholesterol levels by binding to the LDL-receptor (LDLR) and facilitating its lysosomal degradation. PCSK9 gain-of-function mutations have been confirmed as a novel genetic mechanism for familial hypercholesterolemia. Elevated serum PCSK9 levels in patients with vascular diseases may contribute to coronary artery disease, atherosclerosis, cerebrovascular diseases, vasculitis, aortic diseases, and arterial aging pathogenesis. Experimental models of atherosclerosis, arterial aneurysm, and coronary or carotid artery ligation also support PCSK9 contribution to inflammatory response and disease progression, through LDLR-dependent or -independent mechanisms. More recently, several clinical trials have confirmed that anti-PCSK9 monoclonal antibodies can reduce systemic LDL levels, total nonfatal cardiovascular events, and all-cause mortality. Interaction of PCSK9 with other receptor proteins (LDLR-related proteins, cluster of differentiation family members, epithelial Na+ channels, and sortilin) may underlie its roles in vascular disease. Improved understanding of PCSK9 roles and molecular mechanisms in various vascular diseases will facilitate advances in lipid-lowering therapy and disease prevention.

Chinese Public's Engagement in Preventive and Intervening Health Behaviors During the Early Breakout of COVID-19: Cross-Sectional Study.

BACKGROUND: Since January 2020, the coronavirus disease (COVID-19) swept over China and then the world, causing a global public health crisis. People's adoption of preventive and intervening behaviors is critical in curbing the spread of the virus. OBJECTIVE: The aim of this study is to evaluate Chinese people's adoption of health behaviors in responding to COVID-19 and to identify key determinants for their engagement. METHODS: An anonymous online questionnaire was distributed in early February 2020 among Mainland Chinese (18 years or older) to examine their engagement in preventive behaviors (eg, frequent handwashing, wearing masks, staying at home) and intervening behaviors (eg, advising family to wash hands frequently), and to explore potential determinants for their adoption of these health behaviors. RESULTS: Out of 2949 participants, 55.3% (n=1629) reported frequent engagement in preventive health behaviors, and over 84% (n=2493) performed at least one intervening health behavior. Greater engagement in preventive behaviors was found among participants who received higher education, were married, reported fewer barriers and greater benefits of engagement, reported greater self-efficacy and emotional support, had greater patient-centered communication before, had a greater media literacy level, and had greater new media and traditional media use for COVID-19 news. Greater engagement in intervening behaviors was observed among participants who were married, had lower income, reported greater benefits of health behaviors, had greater patient-centered communication before, had a lower media literacy level, and had a greater new media and traditional media use for COVID-19 news. CONCLUSIONS: Participants' engagement in coronavirus-related preventive and intervening behaviors was overall high, and the associations varied across demographic and psychosocial variables. Hence, customized health interventions that address the determinants for health behaviors are needed to improve people's adherence to coronavirus-related behavior guidelines.

PCSK9: A novel inflammation modulator in atherosclerosis?

Proprotein convertase subtilisin/kexin 9 (PCSK9) is the ninth member of the secretory serine protease family. It binds to low-density lipoprotein receptor (LDLR) for endocytosis and lysosome degradation in the liver, resulting in an increasing in circulating LDL-cholesterol (LDL-c) level. Since a PCSK9 induced increase in plasma LDL-c contributes to atherosclerosis, PCSK9 inhibition has become a new strategy in preventing and treating atherosclerosis. However, in addition to the effect of PCSK9 on elevating blood LDL-c levels, accumulating evidence shows that PCSK9 plays an important role in inflammation, likely representing another major mechanism for PCSK9 to promote atherosclerosis. In this review, we discuss the association of PCSK9 and inflammation, and highlight the specific effects of PCSK9 on different vascular cellular components involved in the atherosclerotic inflammation. We also discuss the clinical evidence for the association between PCSK9 and inflammation in atherosclerotic cardiovascular disease. A better understanding of the direct association of PCSK9 with atherosclerotic inflammation might help establish a new role for PCSK9 in vascular biology and identify a novel molecular mechanism for PCSK9 therapy.

Regulating the Warburg effect on metabolic stress and myocardial fibrosis remodeling and atrial intracardiac waveform activity induced by atrial fibrillation.

Atrial fibrillation (AF) is associated with metabolic stress and induces myocardial fibrosis reconstruction by increasing glycolysis. One goal in the treatment of paroxysmal AF (p-AF) is to improve myocardial fibrosis reconstruction and myocardial metabolic stress caused by the Warburg effect. Adopted male canine that rapid right atrial pacing (RAP) for 6 days to establish a p-AF model. The canines were pre-treated with phenylephrine (PE) or dichloroacetic acid (DCA) before exposure to p-AF or non-p-AF. P-wave duration (Pmax), minimum P-wave duration (Pmin), P wave dispersion (PWD), atrial effective refractory period (AERP) and AERP dispersion (AERPd) were measured in canine atrial cardiomyocytes. Pyruvate dehydrogenase kinase-1 (PDK-1), PDK-4, lactate dehydrogenase A (LDHA), pyruvate dehydrogenase (PDH), citrate synthase (CS), isocitrate dehydrogenase (IDH), and matrix metalloproteinase 9 (MMP-9) were evaluated by western blotting and reverse transcription polymerase chain reaction (RT-PCR), content of adenosine monophosphate (AMP), adenosine triphosphate (ATP), lactic acid and glycogen, and activity of LDHA, PDK-1 and PDK-4 were evaluated by enzyme-linked immunosorbent assay (ELISA), myocardial tissue glycogen content was evaluated by PAS, myocardial fibrosis remodeling was evaluated by hematoxylin and eosin (H&E) and Masson staining. Our findings demonstrated that p-AF increases the Warburg effect-related metabolic stress and myocardial fibrosis remodeling by increasing the expression and activity of PDK-1, PDK-4, and LDHA, content of AMP and lactic acid, and the ratio of AMP/ATP and decreasing the expression of PDH, CS, and IDH, and glycogen content. In addition, p-AF can induce cardiomyocyte fibrosis remodeling and increase MMP-9 expression, and p-AF also increases atrial intracardiac waveform activity by prolonging Pmax, Pmin, PWD, and AERPd and shortening AERP. PDK isoforms agonists (PE) produce a similar p-AF pathological effect and can produce synergistic effects with p-AF, further increasing Warburg effect-related metabolic stress, myocardial fibrosis remodeling, and atrial intracardiac waveform activity. In contrast, the use of PDK-specific inhibitors (DCA) completely reverses these pathophysiological changes induced by p-AF. We demonstrate that p-AF can induce the Warburg effect in canine atrial cardiomyocytes and significantly improve p-AF-induced metabolic stress, myocardial fibrosis remodeling, and atrial intracardiac waveform activity by inhibiting the Warburg effect.

Lowering serum lipids via PCSK9-targeting drugs: current advances and future perspectives.

Proprotein convertase subtilisin/kexin type 9 (PCSK9), also known as neural apoptosis regulated convertase (NARC1), is a key modulator of cholesterol metabolism. PCSK9 increases the serum concentration of low-density lipoprotein cholesterol by escorting low-density lipoprotein receptors (LDLRs) from the membrane of hepatic cells into lysosomes, where the LDLRs are degraded. Owing to the importance of PCSK9 in lipid metabolism, considerable effort has been made over the past decade in developing drugs targeting PCSK9 to lower serum lipid levels. Nevertheless, some problems and challenges remain. In this review we first describes the structure and function of PCSK9 and its gene polymorphisms. We then discuss the various designs of pharmacological targets of PCSK9, including those that block the binding of PCSK9 to hepatic LDLRs (mimetic peptides, adnectins, and monoclonal antibodies), inhibit PCSK9 expression (the clustered regularly interspaced short palindromic repeats/Cas9 platform, small molecules, antisense oligonucleotides, and small interfering RNAs), and interfere with PCSK9 secretion. Finally, this review highlights future challenges in this field, including safety concerns associated with PCSK9 monoclonal antibodies, the limited utility of PCSK9 inhibitors in the central nervous system, and the cost-effectiveness of PCSK9 inhibitors.

PI3K/Akt/FoxO3a signaling mediates cardioprotection of FGF-2 against hydrogen peroxide-induced apoptosis in H9c2 cells.

Cardiovascular disease is a growing major global public health problem. Oxidative stress is regarded as one of the key regulators of pathological physiology, which eventually leads to cardiovascular disease. However, mechanisms by which FGF-2 rescues cells from oxidative stress damage in cardiovascular disease is not fully elucidated. Herein this study was designed to investigate the protective effects of FGF-2 in H2O2-induced apoptosis of H9c2 cardiomyocytes, as well as the possible signaling pathway involved. Apoptosis of H9c2 cardiomyocytes was induced by H2O2 and assessed using methyl thiazolyl tetrazolium assay, Hoechst, and TUNEL staining. Cells were pretreated with PI3K/Akt inhibitor LY294002 to investigate the possible PI3K/Akt pathways involved in the protection of FGF-2. The levels of p-Akt, p-FoxO3a, and Bim were detected by immunoblotting. Stimulation with H2O2 decreased the phosphorylation of Akt and FoxO3a, and induced nuclear localization of FoxO3a and apoptosis of H9c2 cells. These effects of H2O2 were abrogated by pretreatment with FGF-2. Furthermore, the protective effects of FGF-2 were abolished by PI3K/Akt inhibitor LY294002. In conclusion, our data suggest that FGF-2 protects against H2O2-induced apoptosis of H9c2 cardiomyocytes via activation of the PI3K/Akt/FoxO3a pathway.

Intrauterine infusion of platelet-rich plasma improves fibrosis by transforming growth factor beta 1/Smad pathway in a rat intrauterine adhesion model.

This study aims to elucidate the effects of Platelet-rich plasma (PRP) in fibrosis development in intrauterine adhesion (IUA), and the associated underlying mechanisms are also explored, which are expected to be a potential therapeutic scheme for IUA. In this research, PRP was obtained and prepared from the peripheral venous blood of rats. A rat model was induced by mechanical injury. Further, PRP was directly injected into the uterus for treatment. The appearance and shape of the uterus were assessed based on the tissues harvested. The fibrosis biomarker levels were analyzed. The transforming growth factor beta 1 (TGF-ß1) and Mothers against decapentaplegic homolog 7 (Smad7) levels, the phosphorylation of Smad2 (p-Smad2), and the phosphorylation of Smad3 (p-Smad3) were analyzed, and the molecular mechanism was investigated by rescue experiments. It was found that PRP improved the appearance and shape of the uterus in IUA and increased endometrial thickness and gland numbers. The administration of PRP resulted in a decrease in the expressions of fibrosis markers including collagen I, α-SMA, and fibronectin. Furthermore, PRP increased Smad7 levels and decreased TGF-ß1 levels, p-Smad2, and p-Smad3. Meanwhile, administration of TGF-ß1 activator reversed the therapeutic effects of PRP in IUA. Collectively, the intrauterine infusion of PRP can promote endometrial damage recovery and improve endometrial fibrosis via the TGF-ß1/Smad pathway. Hence, PRP can be a potential therapeutic strategy for IUA.

A Novel Perspective on PCSK9 in Alzheimer's Disease: A Focus on Amyloid Beta.

The proprotein convertase subtilisin/kexin type 9 (PCSK9) belongs to a member of the proprotein convertase (PC) family, which is mainly secreted by the liver and plays a central role in lipid metabolism. Furthermore, PCSK9 plays a multifunctional role in promoting the inflammatory response, inducing cell apoptosis and pyroptosis and affecting tumor homeostasis. The brain is the organ with the richest lipid content. Incidentally, PCSK9 increased in many brain diseases, including brain injury and Alzheimer's disease (AD). Consequently, the relationship between PCSK9 and brain diseases has attracted increasing research interest. Amyloid beta (Aß) accumulation is the central and initial event in the pathogenesis of AD. This study focuses on the effects of PCSK9 on Aß accumulation in the brain via multiple modalities to explore the potential role of PCSK9 in AD, which is characterized by progressive loss of brain cells by increasing Aß accumulation. The study also explores the new mechanism by which PCSK9 is involved in the pathogenesis of AD, providing interesting and innovative guidance for the future of PCSK9-targeted therapy for AD.

LncRNA: An Important Regulator of Atherosclerosis.

Long non-coding RNA (lncRNA) is a kind of biomolecule that can regulate important life activities such as cell proliferation, apoptosis, differentiation, aging, and body development. It has been found that lncRNAs are closely related to various diseases. In cardiovascular diseases, lncRNAs affect the expression level of related genes in atherosclerotic plaques, which are closely related to endothelial dysfunction, smooth muscle cell proliferation, macrophage dysfunction, abnormal lipid metabolism, and cellular autophagy, thus participating in regulating the occurrence and development of AS. In view of this, investigating the role of lncRNAs in regulating cardiac gene networks on cardiovascular system diseases has attracted much clinical attention and may be a novel target for AS therapy. This paper focuses on lncRNAs related to AS, explores the relationship between lncRNAs and AS, suggests the role of lncRNAs in the prevention and treatment of AS, and expects the application of more lncRNAs as the marker in the clinical diagnosis and treatment of AS.

Non-oxidative modified low-density lipoproteins: The underappreciated risk factors for atherosclerosis.

Atherosclerosis, the pathological basis of most cardiovascular diseases, is a main risk factor causing about 20 million deaths each year worldwide. Oxidized low-density lipoprotein is recognized as the most important and independent risk factor in initiating and promoting atherosclerosis. Numerous antioxidants are extensively used in clinical practice, but they have no significant effect on reducing the morbidity and mortality of cardiovascular diseases. This finding suggests that researchers should pay more attention to the important role of non-oxidative modified low-density lipoprotein in atherosclerosis with a focus on oxidized low-density lipoprotein. This review briefly summarizes several important non-oxidative modified low-density lipoproteins associated with atherosclerosis, introduces the pathways through which these non-oxidative modified low-density lipoproteins induce the development of atherosclerosis in vivo, and discusses the mechanism of atherogenesis induced by these non-oxidative modified low-density lipoproteins. New therapeutic strategies and potential drug targets are provided for the prevention and treatment of atherosclerotic cardiovascular diseases.

A novel cuproptosis-related diagnostic gene signature and differential expression validation in atherosclerosis.

Atherosclerosis (AS) is a major contributor to morbidity and mortality worldwide. However, the molecular mechanisms and mediator molecules involved remain largely unknown. Copper, which plays an essential role in cardiovascular disease, has been suggested as a potential risk factor. Copper homeostasis is closely related to the occurrence and development of AS. Recently, a new cell death pathway called cuproptosis has been discovered, which is driven by intracellular copper excess. However, no previous studies have reported a relationship between cuproptosis and AS. In this study, we integrated bulk and single-cell sequencing data to screen and identify key cuproptosis-related genes in AS. We used correlation analysis, enrichment analysis, random forest, and other bioinformatics methods to reveal their relationships. Our findings report, for the first time, the involvement of cuproptosis-related genes FDX1, SLC31A1, and GLS in atherogenesis. FDX1 and SLC31A1 were upregulated, while GLS was downregulated in atherosclerotic plaque. Receiver operating characteristic curves demonstrate their potential diagnostic value for AS. Additionally, we confirm that GLS is mainly expressed in vascular smooth muscle cells, and SLC31A1 is mainly localized in macrophages of atherosclerotic lesions in experiments. These findings shed light on the cuproptosis landscape and potential diagnostic biomarkers for AS, providing further evidence about the vital role of cuproptosis in atherosclerosis progression.

Pyrroloquinoline quinone inhibits PCSK9-NLRP3 mediated pyroptosis of Leydig cells in obese mice.

Abnormal lipid metabolism and chronic low-grade inflammation are the main traits of obesity. Especially, the molecular mechanism of concomitant deficiency in steroidogenesis-associated enzymes related to testosterone (T) synthesis of obesity dominated a decline in male fertility is still poorly understood. Here, we found that in vivo, supplementation of pyrroloquinoline quinone (PQQ) efficaciously ameliorated the abnormal lipid metabolism and testicular spermatogenic function from high-fat-diet (HFD)-induced obese mice. Moreover, the transcriptome analysis of the liver and testicular showed that PQQ supplementation not only inhibited the high expression of proprotein convertase subtilisin/Kexin type 9 (PCSK9) but also weakened the NOD-like receptor family pyrin domain containing 3 (NLRP3)-mediated pyroptosis, which both played a negative role in T synthesis of Leydig Cells (LCs). Eventually, the function and the pyroptosis of LCs cultured with palmitic acid in vitro were simultaneously benefited by suppressing the expression of NLRP3 or PCSK9 respectively, as well the parallel effects of PQQ were affirmed. Collectively, our data revealed that PQQ supplementation is a feasible approach to protect T synthesis from PCSK9-NLRP3 crosstalk-induced LCs' pyroptosis in obese men.

PCSK9 siRNA inhibits HUVEC apoptosis induced by ox-LDL via Bcl/Bax-caspase9-caspase3 pathway.

This paper investigated the effects of ox-LDL on PCSK9, and the molecular mechanisms of PCSK9 siRNA-inhibited apoptosis induced by ox-LDL in human umbilical vein endothelial cells (HUVECs), to clarify the role of PCSK9 in atherosclerogenesis. HUVECs were incubated with ox-LDL for 24 h. The apoptosis was observed by Hoechst 33258 staining. The expression of PCSK9, LOX-1 mRNAs and proteins was detected by RT-PCR, western blot, respectively. The PCSK9 siRNAs labeled with fluorescence were transfected into HUVECs by Lipofectamine 2000. After transfection for 24 h, cells were treated with ox-LDL for 24 h, HUVECs apoptosis transfected siRNA was detected by Hoechst 33258 staining and flow cytometer. The expression of Bcl-2, Bax, caspase3, 8, 9 was detected by western blot. The activity of caspase3, 9 was detected by kits. Our results showed that apoptosis of HUVECs and the expressions of PCSK9 and LOX-1 were upregulated secondary to induction by ox-LDL in a concentration-dependent manner. However, ox-LDL-induced HUVEC apoptosis and PCSK9 expression, but not LOX-1 expression, were significantly reduced by PCSK9 siRNA. These results demonstrate a linkage between HUVEC apoptosis and PCSK9 expression. Furthermore, we detected the possible pathway involved in apoptotic regulation by PCSK9 siRNA; our results showed that the expression of Bcl-2 decreased, whereas that of Bax increased. In addition, ox-LDL enhanced the activity of caspase9 and then caspase3. Pretreatment of HUVECs with PCSK9 siRNA blocked these effects of ox-LDL. These findings suggest that ox-LDL-induced HUVECs apoptosis could be inhibited by PCSK9 siRNA, in which Bcl/Bax-caspase9-caspase3 pathway maybe was involved through reducing the Bcl-2/Bax ratio and inhibited the activation of both caspase9 and 3.

Effects of NAD+ precursor supplementation on glucose and lipid metabolism in humans: a meta-analysis.

BACKGROUND: This meta-analysis was performed to investigate the effects of nicotinamide adenine dinucleotide (NAD+) precursor supplementation on glucose and lipid metabolism in human body. METHODS: PubMed, Embase, CENTRAL, Web of Science, Scopus databases were searched to collect clinical studies related to the supplement of NAD+ precursor from inception to February 2021. Then the retrieved documents were screened, the content of the documents that met the requirements was extracted. Meta-analysis and quality evaluation was performed detection were performed using RevMan5.4 software. Stata16 software was used to detect publication bias, Egger and Begg methods were mainly used. The main research terms of NAD+ precursors were Nicotinamide Riboside (NR), Nicotinamide Mononucleotide (NMN), Nicotinic Acid (NA), Nicotinamide (NAM). The changes in the levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and fasting blood glucose were mainly concerned. RESULTS: A total of 40 articles were included in the meta-analysis, with a sample of 14,750 cases, including 7406 cases in the drug group and 7344 cases in the control group. The results of meta-analysis showed that: NAD+ precursor can significantly reduce TG level (SMD = - 0.35, 95% CI (- 0.52, - 0.18), P < 0.0001), and TC (SMD = - 0.33, 95% CI (- 0.51, - 0.14), P = 0.0005), and LDL (SMD = - 0.38, 95% CI (- 0.50, - 0.27), P < 0.00001), increase HDL level (SMD = 0.66, 95% CI (0.56, 0.76), P < 0.00001), and plasma glucose level in the patients (SMD = 0.27, 95% CI (0.12, 0.42), P = 0.0004). Subgroup analysis showed that supplementation of NA had the most significant effect on the levels of TG, TC, LDL, HDL and plasma glucose. CONCLUSIONS: In this study, a meta-analysis based on currently published clinical trials with NAD+ precursors showed that supplementation with NAD+ precursors improved TG, TC, LDL, and HDL levels in humans, but resulted in hyperglycemia, compared with placebo or no treatment. Among them, NA has the most significant effect on improving lipid metabolism. In addition, although NR and NAM supplementation had no significant effect on improving human lipid metabolism, the role of NR and NAM could not be directly denied due to the few relevant studies at present. Based on subgroup analysis, we found that the supplement of NAD+ precursors seems to have little effect on healthy people, but it has a significant beneficial effect on patients with cardiovascular disease and dyslipidemia. Due to the limitation of the number and quality of included studies, the above conclusions need to be verified by more high-quality studies.

The Role of Extracellular Non-coding RNAs in Atherosclerosis.

Atherosclerosis (AS) is a complex chronic inflammatory disease that leads to myocardial infarction, stroke, and disabling peripheral artery disease. Non-coding RNAs (ncRNAs) directly participate in various physiological processes and exhibit a wide range of biological functions. The present review discusses how different ncRNAs participate in the process of AS in various carrier forms. We focused on the role and potential mechanisms of extracellular ncRNAs in AS and examined their potential implications for clinical treatment.

Effects of gut microbiota on atherosclerosis through hydrogen sulfide.

Cardiovascular diseases are the leading cause of death and morbidity worldwide. Atherosclerotic cardiovascular disease (ASCVD) is affected by both environmental and genetic factors. Microenvironmental disorders of the human gut flora are associated with a variety of health problems, not only gastrointestinal diseases, such as inflammatory bowel disease, but also extralintestinal organs. Hydrogen sulfide (H2S) is the third gas signaling molecule other than nitric oxide and carbon monoxide. In the cardiovascular system, H2S plays important roles in the regulation of blood pressure, angiogenesis, smooth muscle cell proliferation and apoptosis, anti-oxidative stress, cardiac functions. This review is aiming to explore the potential role of gut microbiota in the development of atherosclerosis through hydrogen sulfide production as a novel therapeutic direction for atherosclerosis.