Metformin and the risk of neurodegenerative diseases in patients with diabetes: A meta-analysis of population-based cohort studies.

AIMS: The association between metformin use and neurodegenerative disease (ND) onset remains controversial. In this systematic review and meta-analysis, we aimed to determine the relationship between metformin use and ND risk based on data from population-based cohort studies. METHODS: Articles were systematically searched in PubMed, EMBASE and Cochrane Library databases. Pooled relative risks (RRs) with 95% CIs were obtained using a random-effects model. Subgroup analyses, sensitivity analyses and meta-regression were performed to identify the sources of heterogeneity and strengthen the results. RESULTS: Twelve population-based cohort studies involving 194,792 participants (94,462 metformin users and 100,330 metformin non-users) were eligible for inclusion in this meta-analysis. The pooled RR of NDs reached 0.77 (95% CI 0.67-0.88) when comparing metformin users with non-users. The effects were more prominent in long-term metformin users (≥4 years) (RR 0.29, 95% CI 0.13-0.44) and studies from Asian countries (RR 0.69, 95% CI 0.64-0.74). The effect estimates were stable when stratified by subtypes of NDs, study designs, and control definitions (p for interaction >0.05). Meta-regression did not identify the coefficients as the sources of heterogeneity (all p > 0.05). CONCLUSIONS: This systematic review and meta-analysis found that metformin use, especially long-term use, was associated with lower ND risk. However, because there was substantial heterogeneity among studies, high-quality randomized controlled trials are still needed to confirm this finding.

Danthron attenuates experimental atherosclerosis by targeting foam cell formation.

NEW FINDINGS: What is the central question of this study? Does danthron alleviate experimental atherosclerosis by inhibiting the formation of foam cells? What are the main findings and their importance? Danthron improved serum lipid profiles and significantly reduced the atherosclerotic plaque areas and lipid accumulation in the aortic root of ApoE-/- mice. Danthron inhibited foam cell formation in oxidized low-density lipoprotein-induced RAW264.7 macrophages. Furthermore, danthron exerted its function in atherosclerosis at least partly through activating the AMP-activated protein kinase-sirtuin 1 signalling pathway. These findings suggest that danthron has the potential to alleviate atherosclerosis. ABSTRACT: Danthron, an ingredient isolated from Rheum palmatum L., has been revealed to reduce lipid accumulation in vitro. This study aimed to discover the effects of danthron on the development of atherosclerosis and to delineate the underlying mechanisms. For in vivo studies, male ApoE-/- mice were fed a high-fat diet and orally treated with danthron (30 or 60 mg/kg/day) for 12 weeks. For in vitro studies, RAW264.7 cells were induced by oxidized low-density lipoprotein (ox-LDL, 50 µg/ml) for 48 h and subsequently administered danthron at appropriate concentrations for 24 h. AMP-activated protein kinase (AMPK) inhibitor compound C was added to ox-LDL-stimulated RAW264.7 cells 2 h before danthron administration to confirm the role of the AMPK signalling pathway in the regulation by danthron of foam cell formation. We found that danthron improved serum lipid profiles, and significantly reduced atherosclerotic plaque areas and lipid accumulation in the aortic root of atherosclerotic mice. Moreover, danthron upregulated the mRNA and protein expression of ATP-binding cassette transporter A1 (ABCA1), ABCG1 and liver X receptor α (LXRα), which play a crucial role in lipid metabolism, and activated the AMPK-sirtuin 1 (SIRT1) pathway. In an in vitro study, danthron inhibited foam cell formation in ox-LDL-induced RAW264.7 macrophages with an increase in the expression of ABCA1, ABCG1 and LXRα as well as activation of the AMPK-SIRT1 pathway. Furthermore, compound C abolished the effects of danthron on lipid accumulation and the protein expression of ABCA1/G1 and LXRα in vitro. Our results highlight that danthron possesses potential benefits in alleviating experimental atherosclerosis by targeting foam cell formation by activating the AMPK-SIRT1 signalling pathway.

Tryptanthrin Regulates Vascular Smooth Muscle Cell Phenotypic Switching in Atherosclerosis by AMP-Activated Protein Kinase/Acetyl-CoA Carboxylase Signaling Pathway.

ABSTRACT: Atherosclerosis (AS) is one of the most severe cardiovascular diseases involved in the phenotypic switching of vascular smooth muscle cells (VSMCs). Tryptanthrin is a natural product with broad biological activities. However, the effect of tryptanthrin on atherosclerotic progression is unclear. The aim of this study was to determine the role of tryptanthrin in AS and explore the potential mechanism. In vitro, primary VSMCs were stimulated with platelet-derived growth factor-BB (PDGF) to induce cell dedifferentiation. Treatment with tryptanthrin (5 µM or 10 µM) suppressed the proliferation and recovered the contractility of VSMCs in the presence of PDGF. The contractile proteins (α-smooth muscle actin, calponin, and SM22α) were increased, and the synthetic protein vimentin was decreased by tryptanthrin in PDGF-induced VSMCs. ApoE-/- mice fed with high-fat diet were used as an in vivo model of AS. Similarly, gavage administration of tryptanthrin (50 mg/kg or 100 mg/kg) attenuated VSMC phenotypic changes from a contractile to a synthetic state in aortic tissues of AS mice. The serum lipid level, atherosclerotic plaque formation, and arterial intimal hyperplasia were attenuated by tryptanthrin. Furthermore, tryptanthrin increased the expression levels of phosphorylated AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) both in vitro and in vivo. Administration of compound C, an AMPK inhibitor, reversed the inhibitory effect of tryptanthrin on VSMC dedifferentiation in vitro. Thus, we demonstrate that tryptanthrin protects against AS progression through the inhibition of VSMC switching from a contractile to a pathological synthetic phenotype by the activation of AMPK/ACC pathway. It provides novel insights into AS prevention and treatment.

Efficacy and Safety of Prolonged Dual Antiplatelet Therapy after Percutaneous Coronary Intervention in Acute Coronary Syndrome Patients.

Objective: It remains controversial whether to extend the course of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI). We conducted a study to investigate the benefits and risks of applying DAPT for different durations after PCI in acute coronary syndromes (ACS) patients in China. What's more, we explored the efficacy of extended DAPT regimen based on ticagrelor. Methods: This single-center prospective cohort study used data obtained from the PHARM-ACS Patient Registration Database. We included all patients who were discharged between April and December 2018. All patients had at least 18 months of follow-up. Patients were divided into two groups according to the duration of DAPT: a 1-year group and a >1-year group. Potential bias between the two groups was adjusted for by propensity score matching using logistic regression. The primary outcomes were major adverse cardiovascular and cerebrovascular events (MACCE), defined as a composite of death, myocardial infarction, and stroke occurring from 12 months after discharge to follow-up visit. The safety endpoint was any significant bleeding event (BARC ≥ 2). Results: Of 3,205 patients enrolled, 2,201 (68.67%) had DAPT prolonged beyond one year. A total of 2,000 patients were successfully propensity score-matched; patients who received DAPT > 1-year (n = 1000), compared with DAPT = 1-year patients (n = 1000), had a similar risk of MACCE (adjusted HR 0.23, 95% CI 0.05-1.10) and significant bleeding events (adjusted HR 0.63, 95% CI 0.32-1.24). The DAPT > 1-year group had a higher risk of revascularization (adjusted HR 3.36, 95% CI 1.64-6.87). Conclusion: Prolonged DAPT may not be of sufficient benefit to ACS patients within 12-18 months after the index PCI to offset the increased risk of significant bleeding events.

Ticagrelor vs. Clopidogrel in Older Patients With Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention: Insights From a Real-World Registry.

Background and Objectives: It is unclear whether more potent P2Y12 inhibitors are of benefit to older patients who are at high risk for both ischemia and bleeding. We conducted an observational study to compare the clinical outcomes of clopidogrel and ticagrelor uses in older patients with an acute coronary syndrome (ACS). Methods: Older patients (aged ≥65 years) with ACS who underwent percutaneous coronary intervention (PCI) were divided into clopidogrel-treated and ticagrelor-treated groups. The primary observational endpoint was the occurrence of net adverse clinical and cerebral events (NACCEs) during a 12-month period, which is defined as the composite endpoint of all-cause death, myocardial infarction (MI), stroke, stent thrombosis, urgent coronary revascularization, and clinically significant bleeding. The secondary endpoints were clinically significant bleeding and major adverse clinical and cerebral events (MACCEs). Results: This study included a total of 2,611 patients. Of them, 1,636 received clopidogrel and 975 received ticagrelor. Between patients receiving clopidogrel and those receiving ticagrelor, no significant differences were noted in NACCE (8.4 vs. 9.7%, respectively; adjusted hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.66-1.12) or MACCE (7.1 vs. 7.0%, respectively; adjusted HR, 1.13; 95% CI, 0.83-1.55) during the 12-month follow-up period. In contrast, the occurrence of clinically significant bleeding was significantly less in clopidogrel-treated patients compared with that in ticagrelor-treated patients (27, 1.7%, vs. 31, 3.2%, respectively; adjusted HR, 0.42; 95% CI, 0.25-0.69). Stratified analyses revealed no significant association between age (≥75 years vs. <75 years) and treatment condition in terms of primary or secondary endpoints. Conclusion: This study showed that clopidogrel and ticagrelor had comparable net clinical benefits in patients with ACS aged ≥65 years. Additionally, clopidogrel was associated with a significantly lower risk of major bleeding than ticagrelor without an increase in ischemic risk. These findings suggest that clopidogrel is an effective alternative to the more potent P2Y12 inhibitor ticagrelor in older patients.

Clopidogrel versus Ticagrelor in CYP2C19 Loss-of-Function Allele Noncarriers: A Real-World Study in China.

OBJECTIVE: This article compares the clinical outcomes of clopidogrel and ticagrelor in patients with acute coronary syndrome (ACS) without cytochrome P450 (CYP)2C19 loss-of-function (LOF) alleles and investigates whether clopidogrel could be an alternative P2Y12 inhibitor without increasing the risk of ischemic events. METHODS: Patients were divided into the clopidogrel-treated group and the ticagrelor-treated group. Inverse probability of treatment weighting (IPTW) calculated by propensity scores was used to adjust confounding covariates. The primary outcome was major adverse cardiovascular or cerebrovascular events (MACCEs) within 12 months. The secondary outcomes were MACCEs plus unstable angina, and clinically significant bleeding events. RESULTS: Finally, 2,199 patients were included. Of them, 1,606 were treated with clopidogrel, and 593 were treated with ticagrelor. The mean age of the original cohort was 59.92 ± 9.81 years. During the 12-month follow-up period, MACCEs occurred in 89 patients (4.0%). No significant differences were observed in MACCEs (IPTW-adjusted hazard ratio [HR], 0.87; 95% confidence interval [CI], 0.65-1.18), MACCEs plus unstable angina (IPTW-adjusted HR, 1.20; 95% CI, 0.91-1.59), or clinically significant bleeding events (IPTW-adjusted HR, 0.81; 95% CI, 0.53-1.23) between the clopidogrel- and ticagrelor-treated groups. CONCLUSION: In patients with ACS without CYP2C19 LOF alleles, clopidogrel was not associated with a higher risk of MACCEs when compared with ticagrelor. The main findings of this study support use of clopidogrel in CYP2C19 LOF noncarriers as an alternative P2Y12 inhibitor, which may reduce medical expenses and adverse reactions caused by more potent P2Y12 inhibitors in these patients.

Convallatoxin Promotes M2 Macrophage Polarization to Attenuate Atherosclerosis Through PPARγ-Integrin αvß5 Signaling Pathway.

INTRODUCTION: As the primary immune cells, macrophages play a key role in atherosclerotic progression. M2 macrophage polarization has been reported to promote tissue repair and attenuate plaque formation upon the expression of anti-inflammatory factors. Convallatoxin (CNT) is a natural cardiac glycoside with anti-inflammatory pharmacological properties. However, whether CNT protects against atherosclerosis (AS) and underlying mechanisms is unknown. This work was designed to explore the potential effects of CNT on atherosclerosis. METHODS: In this study, Apolipoprotein E deficiency (ApoE-/-) mice fed with high-fat diet were established, and CNT (50 or 100 µg/kg) were intragastrically administrated for 12 weeks every day. In vitro, RAW264.7 macrophages stimulated with ox-LDL were treated with CNT (50 or 100 nM) for 24 h. The specific PPARγ antagonist, GW9662, was used to block the PPARγ signaling pathway in vitro. Then, the atherosclerotic lesions, macrophage polarization markers, inflammatory cytokines and PPARγ signaling pathway were examined in further examinations. RESULTS: Our results showed that the atherosclerotic lesions were reduced by CNT, as demonstrated by the downregulation of serum lipid level and aortic plaque area in AS mice. Furthermore, we found that CNT treatment promoted the expression of M2 macrophage markers (Arg1, Mrc1, Retnla and Chi3l3), and decreased the levels of pro-inflammatory cytokines (IL-6 and TNF-α), accompanied by the increase of anti-inflammatory factor (IL-10) in aortic vessels of AS mice. In ox-LDL-induced RAW264.7 cells, CNT administration also facilitated macrophages polarizing towards M2 subtype and inhibited inflammatory responses. Furthermore, both the in vivo and in vitro experiments showed CNT could increase the expression of PPARγ, Integrin αv and Integrin ß5, and GW9662 could block CNT-induced M2 macrophage polarization. CONCLUSION: Taken together, these data suggest that CNT may promote M2 macrophage polarization to exert an anti-atherosclerotic effect, partially through activating PPARγ-Integrin αvß5 signaling pathway.

Personalized Antiplatelet Therapy Based on CYP2C19 Genotypes in Chinese ACS Patients Undergoing PCI: A Randomized Controlled Trial.

Background: The clinical benefits of cytochrome P450 (CYP) 2C19 genotype-guided antiplatelet therapy in Asians remain unclear. In this study, we aimed to investigate the clinical outcomes of pharmacogenomic antiplatelet therapy in Chinese patients. Methods: Patients with acute coronary syndrome planning to undergo percutaneous coronary intervention were eligible for this study and were randomly divided into a genotype-guided treatment (GT) group and routine treatment (RT) group, with a ratio of 2:1. Patients in the GT group underwent CYP2C19 genotyping (*2 and *3 alleles), and the results were considered in selecting P2Y12 receptor inhibitors. Patients in the RT group were treated with P2Y12 receptor inhibitors according to their clinical characteristics. The primary endpoint was a composite of major adverse cardiovascular or cerebrovascular events (MACCE). The secondary endpoint was significant bleeding events. Results: Finally, 301 patients were enrolled; 75.1% were men and the mean age was 59.7 ± 9.8 years. In total, 281 patients completed the follow-up procedure. The primary endpoint occurred in 16 patients, 6 patients in the GT group and 10 in the RT group. The GT group showed lower MACCE rates than the RT group (6/189 vs. 10/92, 3.2 vs. 10.9%, hazard ratio: 0.281, 95% confidence interval: 0.102-0.773, P = 0.009). There was no statistically difference in significant bleeding events between the GT and RT groups (4.2 vs. 3.3%, hazard ratio: 1.315, 95% confidence interval: 0.349-4.956, P = 0.685). Conclusion: Personalized antiplatelet therapy that is based on CYP2C19 genotypes could decrease MACCE within a 12-month period in Chinese patients with acute coronary syndrome undergoing percutaneous coronary intervention. Clinical Trial Registration: http://www.chictr.org.cn, identifier: ChiCTR2000034352.

Towards low cost, multiplex clinical genotyping: 4-fluorescent Kompetitive Allele-Specific PCR and its application on pharmacogenetics.

Single-nucleotide polymorphisms (SNPs) is associated with efficacy of specific drugs. Although there are several methods for SNP genotyping in clinical settings, alternative methods with lower cost, higher throughout and less complexity are still needed. In this study, we modified Kompetitive Allele Specific PCR to enable multiplex SNP genotyping by introducing additional fluorescent cassettes that specifically help to differentiate more amplification signals in a single reaction. This new format of assay achieved a limit of detection down to 310 copies/ reactions for simultaneous detection of 2 SNPs with only standard end-point PCR workflow for synthetic controls, and genotyped 117 clinical samples with results that were in 100% agreement with hospital reports. This study presented a simplified, cost-effective high-throughput SNP genotyping alternative for pharmacogenetic variants, and enabled easier access to pharmaceutical guidance when needed.

Distribution Analysis of Salvianolic Acids in Myocardial Ischemic Pig Tissues by Automated Liquid Extraction Surface Analysis Coupled with Tandem Mass Spectrometry.

The distribution of active compounds of traditional Chinese medicine Salvia miltiorrhiza Bunge (Chinese name: Danshen) in vivo was determined by establishing a liquid extraction surface analysis coupled with the tandem mass spectrometry (LESA-MS/MS) method. Stability analysis and distribution analysis were designed in the present study using normal animals or a myocardial ischemia model. The model assessment was performed four weeks after surgery, and then three groups were created: a normal-dose group, a model-blank group, and a model-dose group. Meanwhile, Danshen decoction administration began in dose groups and lasted for four weeks. In stability analysis, four salvianolic acids-Danshensu (DSS), caffeic acid (CAA), rosmarinic acid (RA), and salvianolic acid A (SAA)-in kidney tissues from the normal-dose group were detected by LESA-MS/MS under four conditions, and then distribution analysis was conducted in different tissues using the same method. Ejection fraction (EF) and fractional shortening (FS) in animals from two model groups decreased significantly four weeks after surgery (P < 0.01) and were improved after four weeks of Danshen decoction administration (P < 0.01). Results of stability analysis demonstrated that this method was basically stable since there were no significant differences in signal intensities of DSS, CAA, and SAA under four conditions (P > 0.05). Distribution analysis showed the signal intensities of DSS in the liver and kidney and SAA in the heart were higher in the model-dose group than in the normal-dose group (P < 0.05 or P < 0.01). Signal intensities of RA in the liver and kidney, and SAA in the liver were lower in the model-dose group compared with the normal-dose group (P < 0.05 or P < 0.01). In conclusion, Danshen decoction has the effect of improving the ischemic condition in a chronic myocardial ischemia model, and the content of two active compounds increased in the targets. These findings contribute to an understanding of the therapeutic role of Danshen in cardiovascular disease.

Impact of Implementing CYP2C19 Genotype-Guided Antiplatelet Therapy on P2Y12 Inhibitor Selection and Clinical Outcomes in Acute Coronary Syndrome Patients After Percutaneous Coronary Intervention: A Real-World Study in China.

Background: CYP2C19 loss-of-function (LOF) alleles reduce the effectiveness of clopidogrel in patients undergoing percutaneous coronary intervention for acute coronary syndrome. However, the clinical impact of implementing CYP2C19 gene-guided pharmacotherapy is unclear, especially among the Chinese population. The purpose of this study was to evaluate P2Y12 receptor inhibitor selection and clinical outcomes upon implementation of CYP2C19 genotype-guided pharmacotherapy in current clinical practice. Methods: This was a single-center observational cohort study. Adult percutaneous coronary intervention patients who received CYP2C19 genetic testing (*2, *3, *17 alleles) were included. Ticagrelor was recommended for patients with a LOF allele. Factors related to P2Y12 inhibitor selection were determined by logistic regression. The primary endpoint was major cardiac or cerebrovascular adverse events (MACCE) within 12 months. MACCE and clinically significant bleeding events (BARC ≥2) in the LOF-clopidogrel group, non-LOF-clopidogrel group, and non-LOF-ticagrelor group were compared with those in the LOF-ticagrelor group. The inverse probability of treatment weighting (IPTW) was adjusted in a Cox regression analysis to eliminate confounding factors. Results: Among 1,361 patients, 826 (60.7%) had a LOF allele. Patients with a LOF allele were more likely to be prescribed ticagrelor (multivariate-adjusted OR 1.349; 95% CI 1.040 to 1.751; p = 0.024). The MACCE rate was higher in the LOF-clopidogrel group than in the LOF-ticagrelor group (7.8 vs. 4.0%; log-rank p = 0.029; IPTW-adjusted HR 2.138; 95% CI 1.300-3.515). Compared with the LOF-ticagrelor group, the non-LOF-clopidogrel group showed no significant difference in MACCE rate (5.8 vs. 4.0%; log-rank p = 0.272; IPTW-adjusted HR 1.531; 95% CI 0.864-2.714). Among the patients treated with ticagrelor, there was no significant difference in the MACCE rate between the LOF group and non-LOF group (4.3 vs. 4.0%; log-rank p = 0.846; IPTW-adjusted HR 1.184; 95% CI 0.582-2.410). There was no significant difference in the incidence of clinically significant bleeding events among the four groups. Conclusion: This study confirms that efficiently returned CYP2C19 genotype results did partially guide cardiologists to prescribe ticagrelor for patients with a LOF allele, and that clopidogrel had a higher risk of MACCE than ticagrelor in these patients, which provides support for the implementation of CYP2C19 gene-guided antiplatelet therapy in clinical practice.

Both CYP2C19 and PON1 Q192R Genotypes Influence Platelet Response to Clopidogrel by Thrombelastography in Patients with Acute Coronary Syndrome.

OBJECTIVE: The objective of this study is to explore the relationships of the effects of CYP2C19 and PON1 Q192R polymorphism on the activity of clopidogrel and the risk of high platelet responsiveness (HPR) by thrombelastography in patients with acute coronary syndrome (ACS). METHODS: 459 ACS patients with aspirin and clopidogrel were enrolled in this observational case control study from July 13, 2015, to November 11, 2017. The patients with <30% platelet inhibition were defined as HPR group, while the others were defined as normal platelet responsiveness (NPR) group. The genotypes distribution between the groups was assessed, and the clinical impact of genetic variants was investigated by comparing the relationship between the risk of HPR and genotypes including CYP2C19⁎2, CYP2C19⁎3, CYP2C19⁎17, ABCB1, and PON1. RESULTS: Compared with CYP2C19⁎1/⁎1 wild type carriers, CYP2C19⁎2 and ⁎3 carriers showed a significant association with the lower platelet inhibition (P=0.048). The platelet inhibition in carriers of at least one CYP2C19 loss-of-function (LOF) alleles was obviously higher than noncarriers (P=0.031). The platelet inhibition of PON1 192R carriers was lower than PON1 192Q carriers (P=0.044). Patients with the CYP2C19⁎2 and ⁎3 alleles had a greater risk of HPR than CYP2C19 wild type carriers (adjusted P=0.018 and adjusted P=0.005). At least one PON1 192R carrier predicted a significantly higher risk of HPR than PON1 192Q carriers (adjusted P=0.021). Individual CYP2C19⁎17 and ABCB1 variants did not differ significantly between the two groups. CONCLUSIONS: CYP2C19 and PON1 Q192R variants influence ADP-induced platelet inhibition by thrombelastography (TEG) in ACS patients with clopidogrel. In addition, both LOF CYP2C19 and PON1 192R variants are independent risk factors of HPR, which is measured by the relative platelet inhibition.