Cardiovascular Toxicology

Antoniewicz, Lukasz; Melnikov, Georgy; Lyytinen, Gustaf; Blomberg, Anders; Bosson, Jenny A.; Hedman, Linnea; Mobarrez, Fariborz; Lundbäck, Magnus

doi: 10.1007/s12012-024-09934-6pmid: 39472409

The advent of heated tobacco products (HTPs) has introduced new variables in the study of nicotine delivery systems and their health implications. Amidst concerns over cardiovascular effects, this study aims to elucidate the acute impact of HTP inhalation on extracellular vesicles (EV) levels in young, healthy individuals. In this controlled, acute exposure study, 23 young, healthy volunteers were subjected to HTP inhalation. EV levels of endothelial and platelet origin were quantified through flow cytometry before and after exposure. Data analysis was performed using multiple measures ANOVA to assess changes in EV concentrations. Our findings reveal a significant increase in EVs of endothelial and platelet origin following short-term HTP inhalation with nicotine. Notably, no significant change was observed in leukocyte- and neutrophil-derived EVs. This increase in EVs suggests acute vascular stress, with peak levels observed 4 h post-exposure. The rise in endothelial and platelet-derived EVs aligns with documented responses to acute vascular injury, paralleling the effects seen with traditional cigarette and e-cigarette use. Despite HTPs being marketed as safer alternatives, our results indicate that nicotine-containing HTPs may still pose significant vascular risks. These findings contribute to the growing body of evidence cautioning against the perceived safety of HTPs and reinforce the importance of regulatory oversight and public health initiatives targeting nicotine delivery technologies. Trial Registrations: ClinicalTrials.gov ID: NCT04824495, registered 2021–01-07.

Gao, Hong-Li; Yang, Yu; Tian, Hua; Fu, Li-Yan; Liu, Kai-Li; Jia, Xiu-Yue; Shi, Xiao-Lian; Kang, Yu-Ming; Yu, Xiao-Jing

doi: 10.1007/s12012-024-09938-2pmid: 39467886

The hypothalamic paraventricular nucleus (PVN), as an important integrating center, plays a prominent role in the pathogenesis of hypertension, in maintaining the stability of cardiovascular activity through peripheral sympathetic nervous activity and secretion of various humoral factors. Acknowledging that the mechanistic targets of the endocannabinoid type 1 receptor (CB1R) are the key signaling systems involved in the regulation of hypertension, we sought to clarify whether inhibition of CB1R within the PVN ameliorates hypertension through Wnt/β-catenin/RAS pathway. Spontaneously hypertensive rats (SHRs) and Wistar Kyoto rats were randomly assigned to different groups and treated with bilateral PVN injections of AM251 (CB1R antagonist, 10 µg/h) or vehicle (artificial cerebrospinal fluid, aCSF) for four weeks. Bilateral PVN injections of AM251 significantly decreased the heart rate, the body weight and the mean arterial pressure in SHRs. AM251 lowered the expression of CB1R, Wnt3, active-β-catenin, p-IKKβ, RAS components, pro-inflammatory cytokines and elevated the expression level of Glycogen synthase kinase3β and Superoxide Dismutase in the PVN of hypertensive rats. Our findings suggest that inhibition of CB1R in the PVN ameliorates hypertension through Wnt/β-catenin/RAS pathway and broaden our current understanding of the pathological mechanism and clinical treatment of hypertension.Graphical Abstract[graphic not available: see fulltext]

Yuan, Minjie; Feng, Linjuan; Zhao, Dongqi; Shi, Dongdong; Wang, Hui; Wei, Junbo; Wang, Man

doi: 10.1007/s12012-024-09939-1pmid: 39542955

The objective of this study is to determine the diagnostic utility of combining homocysteine (HCY), lipoprotein-associated phospholipase A2 (LP-PLA2), and the C-reactive protein-to-albumin ratio (CAR) for carotid atherosclerosis (CAS) and plaque stability in patients with essential hypertension (EH). A total of 280 patients with EH were divided into 2 groups according to ultrasound diagnosis: CAS (n = 106) and non-CAS (N-CAS [n = 174]). The CAS group was further segmented into plaque-stable (n = 50) and plaque non-stable (n = 56) groups. General data were collected for all patients. Risk factors associated with CAS and plaque instability in patients with EH, and the diagnostic utility of HCY, LP-PLA2, and CAR testing alone, or in combination, for assessing CAS and plaque instability were determined. Mean age, systolic blood pressure (SBP), duration of EH, smoking, total cholesterol high-density lipoprotein cholesterol, HCY, LP-PLA2 levels, and CAR were higher in the CAS group than those in the N-CAS group (P < 0.05). SBP, duration of EH, HCY and LP-PLA2 levels, and CAR were independent risk factors for CAS (P < 0.05). In addition, HCY, LP-PLA2, and CAR alone demonstrated significant diagnostic efficacy (P < 0.001) but were inferior to the combined diagnostic utility of the 3 parameters (P < 0.001). HCY and LP-PLA2 levels, and CAR were higher in the plaque non-stable than in the plaque-stable group (P < 0.05). Duration of EH, low-density lipoprotein cholesterol, HCY, LP-PLA2, and CAR independently influenced plaque instability in patients with CAS (P < 0.05). The combined diagnostic utility of HCY, LP-PLA2, and CAR (P < 0.001) was superior to that of each parameter alone and demonstrated more pronounced diagnostic efficacy (P < 0.001). HCY, LP-PLA2, and CAR were independent risk factors for CAS and plaque instability in patients with EH. HCY, LP-PLA2, and CAR demonstrated significant diagnostic efficacy for CAS and plaque instability, and combination of the 3 demonstrated the most pronounced diagnostic efficacy.Graphical Abstract[graphic not available: see fulltext]

Wu, Lili; Yang, Bo; Sun, Yingze; Fan, Guanwei; Ma, Lina; Ma, Ying; Xiong, Xianjia; Zhou, Hui; Wang, Huiping; Zhang, Ling; Yang, Bing

doi: 10.1007/s12012-024-09937-3pmid: 39521734

Histone demethylation in cardiac hypertrophy is poorly understood. This study aims to determine the role of the histone demethylase LSD1 in pathological cardiac hypertrophy. Both isoprenaline (ISO)-treated and transverse aortic constriction (TAC)-treated rats developed hypertrophic hearts. LSD1 was significantly decreased; the histone marks mono- and dimethyl H3K4 and H3K9 (H3K4me1/2 and H3K9me1/2) were significantly up-regulated in the hypertrophic heart tissue, as well as the expression of the ANP, α-HMC and MLV-2v genes. An LSD1 inhibitor, OG-L002 could also induce cardiac hypertrophy and enhance the induction of cardiac hypertrophy by ISO. Overexpressed LSD1 abolished ISO-induced cardiac hypertrophy and downregulated H3K4me1/2 and H3K9me1/2 expression. Overexpression of LSD1 also reduced the expression of ANP, α-HMC and MLV-2v. In addition, we have reported isoprenaline (ISO) as one of the histone demethylase LSD1 inhibitors. This was confirmed by molecular docking, molecular dynamic studies and a histone demethylation assay. The H3K4me1/2 expression increases with the incubation of ISO in HEK 293T and HELA cells. CaMKII could be significantly activated by the LSD1 inhibitor OG-L002 as well as by ISO in rats. In summary, we have identified a novel role for LSD1 in initiating and maintaining cardiac hypertrophy.Graphical Abstract[graphic not available: see fulltext]

Guo, Yafei; Li, Bowen; Yan, Yu; Zhang, Nanjun; Shao, Shuran; Yang, Lixia; Ouyang, Lixue; Wu, Ping; Ma, Fan; Duan, Hongyu; Zhou, Kaiyu; Hua, Yimin; Wang, Chuan

doi: 10.1007/s12012-024-09936-4

Shen, Cheng; Wei, Yanian; Kang, Wen; Wang, Qianwen; Li, Guoqiang; Chen, Xin; Wang, Long

doi: 10.1007/s12012-024-09942-6pmid: 39495463

The role of ferroptosis, an iron-dependent lipid peroxidation regulated cell death pathway, remains obscure during myocardial infarction (MI) recovery. Our study aims to clarify ferroptosis’ function in post-MI cardiac recovery, explore the consequences of iron overload and ferroptosis for myocardial remodeling, and assess the effects of Liproxstatin-1 (Lipro-1) treatment on macrophage functionality. Moreover, we examine the potential of Astaxanthin (ASTX), recognized for its antioxidative properties, to mitigate ferroptosis during MI recovery and its subsequent ramifications for myocardial remodeling. Our results demonstrate persistent ferroptosis during MI recovery, marked by decreased Glutathione Peroxidase 4 and increased Acyl-CoA Synthetase Long-Chain Family Member 4 (ACSL4) and Ferroportin 1 alongside elevated lipid peroxidation and iron levels up to D21. We identified a significant correlation between ferroptosis and macrophage activity, noted by the increase in macrophage populations co-expressing GPX4 and ACSL4 markers in the peri-infarct area by D21. Liproxstatin-1 treatment reduced macrophage (CD68 +) counts, promoted M2 polarization decreased inflammation, and improved cardiac function. Myocardial remodeling was improved in Lipro-1-treated rats, as shown by decreased fibrosis and reduced levels of α-SMA, Collagen I, and Collagen III proteins. ASTX treatment also exhibited an inhibiting effect on ferroptosis indicators, and encouraged M2 macrophage polarization, reduced inflammation, and enhanced both cardiac function and myocardial remodeling, mirroring the beneficial effects observed with Lipro-1. In summary, the interactions between ferroptosis, macrophage polarization, and myocardial remodeling are crucial for cardiac function improvement post-MI. Lipro-1 and ASTX emerge as promising therapeutic agents by modulating post-MI ferroptosis and related immune responses.

Yang, Lei; Gao, Tong; Huang, Yu; Wang, Pei-he; Han, Xin-hao; Wu, Jie; Huang, Lei; Da, Qing-en; Ouyang, Kun-fu; Han, Zhen; Tian, Hai; Sun, Lu

doi: 10.1007/s12012-024-09946-2pmid: 39656360

Gene therapy has received great attention as a therapeutic approach to improve cardiac function post-myocardial infarction (MI), but its limitation lies in the lack of targeting. This study explored the use of ultrasound-targeted microbubble destruction (UTMD) technique to deliver β-catenin gene to the myocardium, aiming to evaluate its efficacy in preventing cardiac dysfunction post-MI. A cationic microbubble solution containing β-catenin gene pcDNA3.1 plasmid was injected through the tail vein at a rate of 0.6 mL/h, and ultrasound beams were delivered to the heart using GE Vivid 7 Medical Ultrasound System M3s Transducer. Bioluminescence imaging was used to analyze the efficiency of UTMD gene transfection into the myocardium. β-catenin levels were detected by real-time polymerase chain reaction and western blot. Additionally, MI was induced in mice by surgical ligation of the left coronary artery, and cardiac function was evaluated using echocardiography at 14 and 28 days post-surgery. Masson’s trichrome staining was employed to determine infarct size. Blood vessel density was also measured. TUNEL assay was used to measure cardiomyocyte apoptosis. Furthermore, mouse cardiac stem cells were isolated using flow cytometry, and Giemsa stain was applied to evaluate the colony adhesion. UTMD delivered the gene to the heart with high efficiency and specificity in vivo. The β-catenin expression was significantly increased in the myocardium (P < 0.01). After MI, the β-catenin group exhibited a notable improvement in the gene therapy-induced neovascularization in the border zone (P < 0.01) and the number and function of cardiac stem cells (P < 0.01), and a significant decrease in cardiomyocyte apoptosis in the heart tissue (P < 0.01). β-catenin gene pre-treated with UTMD can reduce the impact of myocardial injury and promote cardiac self-repair after MI.

Bernhardt, Maria Fernanda Conte; Ronconi-Krüger, Nathália; Nazari, Evelise Maria

doi: 10.1007/s12012-024-09944-4pmid: 39527374

In recent years, concerns have been raised regarding the safety of exposure to pyriproxyfen (PPF), a larvicide commonly used in drinking water reservoirs to control populations of disease-vector mosquitoes for human safety. These concerns are focused mainly on exposure by pregnant women, since studies have shown deleterious effects of PPF on embryonic development, mainly addressing the central nervous system. However, since previous studies showed reduced growth in embryos exposed to PPF, we hypothesize that PPF exposure impairs the cardiovascular system, responsible for ensuring appropriate blood supply, which leads to stunted growth. This study aimed to investigate the impact of PPF exposure on heart ventricular morphology, its influence on cell proliferation and apoptosis, as well as assess the impact on the functionality of the heart and on embryonic growth. Chicken embryos were used as a model and two sublethal concentrations were tested: 0.01 mg/L and 10 mg/L PPF. Thinning of cardiac tissue was evident in heart structures at 10 mg/L PPF. Furthermore, DNA double-strand breaks and reduced cell proliferation were observed, combined with decreased apoptosis suggesting cell cycle arrest, especially in the left ventricle for both concentrations. In addition, these PPF concentrations induced heart arrhythmia, although no changes in heart rate were observed. Embryos exposed to 0.01 mg/L showed reduced body and heart mass, crown-rump length, and thoracic perimeter, while head circumference was reduced in both exposed groups. Together, combining morphological, molecular, and physiological parameters, this study showed the cardiotoxic effects of PPF exposure and elucidated its impacts on embryonic growth.Graphical Abstract[graphic not available: see fulltext]

Zhang, Guoyong; Ma, Zhimin; Ma, Zheng; Liu, Peilin; Zhang, Lin; Lian, Zheng; Guo, Caixia

doi: 10.1007/s12012-024-09950-6pmid: 39729180

Nuclear factor erythroid 2-related factor 2 (NRF2) is a redox-sensitive transcriptional factor that enables cells to resist oxidant responses, ferroptosis and inflammation. Here, we set out to probe the effects of NRF2 on cardiomyocyte injury under acute myocardial infarction (AMI) condition and its potential mechanism. Human cardiomyocytes were exposed to hypoxia/reoxygenation (H/R) to induce cell injury. qRT-PCR and western blot assays were used to detect the levels of mRNAs and proteins. Cardiomyocyte injury was determined by detecting the levels of lactate dehydrogenase and creatine Kinase MB (CK-MB). Cell apoptosis was investigated by flow cytometry and related markers. Levels of IL-6, IL-10, and TNF-α were measured by ELISA. Cell ferroptosis was assessed by detecting the production of reactive oxygen species (ROS), malonaldehyde (MDA), reduced glutathione/oxidized glutathione disulfide (GSH/GSSG) ratio, Fe + content, and related regulators. The interaction between NRF2 and the suppressor of zest 12 (SUZ12) was analyzed by using dual-luciferase reporter and RNA immunoprecipitation assays. AMI rat models were established for in vivo analysis. NRF2 was lowly expressed in AMI patients and H/R-induced cardiomyocytes. Forced expression of NRF2 reduced H/R-induced cardiomyocyte injury, apoptosis, inflammation, and ferroptosis. Moreover, NRF2 overexpression improved cardiac function and injury in vivo. Mechanistically, SUZ12 bound to the promoter of NRF2 and promoted its expression. Further functional analyses showed that SUZ12 overexpression reduced H/R-induced cardiomyocyte injury, apoptosis, inflammation, and ferroptosis, which were reversed by NRF2 silencing. SUZ12-increased NRF2 suppressed H/R-induced cardiomyocyte injury, apoptosis, inflammation, and ferroptosis in vitro and improved cardiac functions in rats with I/R injury, suggesting the potential cardioprotective effect of NRF2 in cardiac injury during AMI.Graphical abstract[graphic not available: see fulltext]

Shi, Binhao; Wang, Jianfei; Zhang, Jing; Li, Ji; Hao, Yancheng; Lin, Xianhe; Zhao, Ren

doi: 10.1007/s12012-024-09945-3pmid: 39560681

Diabetic cardiomyopathy (DCM) is a common and severe complication of Diabetes mellitus (DM). Dapagliflozin (DAPA) is an oral anti-diabetic drug worldwide for the treatment of type 2 DM. However, the action and mechanism of DAPA in cardiac fibrosis during DCM remain vague. Primary cardiac fibroblasts (CFs) were incubated with high glucose (HG) in vitro. Cell proliferation was detected by MTT and EdU assays. Oxidative stress was evaluated by determining the production of reactive oxygen species and malondialdehyde. Cell fibrosis was assessed by detecting fibrosis-related proteins by western blotting. Levels of Mettl3 (Methyltransferase 3) and Marcks (myristoylated alanine-rich C kinase substrate) were measured using qRT-PCR and western blotting. The m6A modification profile was determined by methylated RNA immunoprecipitation assay and the interaction between Mettl3 and Marcks was verified using dual-luciferase reporter and RIP assays. DAPA treatment alleviated HG-induced proliferation, oxidative stress, and fibrosis in CFs. HG promoted the expression of Mettl3 in CFs. Knockdown of Mettl3 reversed HG-induced proliferation, oxidative stress, and fibrosis in CFs; moreover, forced expression of Mettl3 abolished the protective effects of DAPA on CFs under HG condition. Mechanistically, Mettl3 interacted with Marcks in CFs and induced Marcks mRNA m6A modification. HG induced high expression of Marcks in CFs. The overexpression of Marcks could counteract DAPA or Mettl3 knockdown-evoked inhibitory effects on CF proliferation, oxidative stress, and fibrosis under HG condition. Dapagliflozin suppressed HG-induced proliferation, oxidative stress, and fibrosis by reducing Mettl3-induced m6A modification in Marcks mRNA.