Cardiovascular diseases are the leading cause of death and the main cause of disability. In the last decade, homocysteine has been found to be a risk factor or a marker for cardiovascular diseases, including myocardial infarction (MI) and heart failure (HF). There are indications that vitamin B6 plays a significant role in the process of transsulfuration in homocysteine metabolism, specifically, in a part of the reaction in which homocysteine transfers a sulfhydryl group to serine to form α-ketobutyrate and cysteine. Therefore, an elevated homocysteine concentration (hyperhomocysteinemia) could be a consequence of vitamin B6 and/or folate deficiency. Hyperhomocysteinemia in turn could damage the endothelium and the blood vessel wall and induce worsening of atherosclerotic process, having a negative impact on the mechanisms underlying MI and HF, such as oxidative stress, inflammation, and altered function of gasotransmitters. Given the importance of the vitamin B6 in homocysteine metabolism, in this paper, we review its role in reducing oxidative stress and inflammation, influencing the functions of gasotransmitters, and improving vasodilatation and coronary flow in animal models of MI and HF.
1 May 2023 in Canadian Journal of Physiology and Pharmacology
Type 2 diabetes mellitus (T2DM) increases the risk of cardiovascular disease, especially myocardial injury. Due to their hypoglycemic effects, glucagon-like peptide-1 receptor agonists (GLP-1RAs) are efficiently used for T2DM management. GLP-1RAs also have anti-inflammatory and antioxidative effects and can improve cardiac function. The aim of this study was to investigate the cardioprotective effects of liraglutide, a GLP-1RA, on isoprenaline-induced myocardial injury in rats. The study included four groups of animals. They were pretreated with saline for 10 days + saline on days 9 and 10 (control), saline for 10 days + isoprenaline on days 9 and 10 (isoprenaline group), liraglutide for 10 days + saline on days 9 and 10 (liraglutide group), and liraglutide for 10 days, and on days 9 and 10 isoprenaline was administered. This study evaluated ECG, myocardial injury markers, oxidative stress markers, and pathohistological changes. The results showed that liraglutide mitigated the isoprenaline-induced cardiac dysfunction recorded by ECG. Liraglutide reduced serum markers of myocardial injury such as high-sensitive troponin I, aspartate aminotransferase, alanine aminotransferase, reduced thiobarbituric acid reactive substances, increased catalase and superoxide dismutase activity, increased reduced glutathione level, and improved lipid profile. Liraglutide induced antioxidative protection and alleviated isoprenaline-induced myocardial injury.
Takotsubo syndrome (TTS) is a stress-induced cardiomyopathy, characterized by an increased concentration of catecholamines, free radicals, and inflammatory cytokines, endothelial dysfunction, and increased apoptotic activity. High doses of isoprenaline are used in animal models to induce Takotsubo (TT)-like myocardial injury. The aim of the study was to investigate the antiapoptotic effects of liraglutide in experimental TTS and its role in the NF-κB pathway. Wistar rats were pretreated with liraglutide for 10 days, and on days 9 and 10, TT-like myocardial injury was induced with isoprenaline. After the sacrifice on day 11, hearts were isolated for histopathological and immunohistochemical analysis. Liraglutide reduced isoprenaline-induced cardiomyocyte apoptosis by decreasing cleaved caspase-3 (CC3), BCL-2-associated X protein (BAX), and NF-κB and increasing B-cell lymphoma/leukemia-2 (BCL-2). An increase in NF-κB in isoprenaline-treated rats was in positive correlation with proapoptotic markers (BAX and CC3) and in negative correlation with antiapoptotic marker BCL-2. Liraglutide increased BCL-2 and decreased NF-κB, BAX, and CC3, preserving the same correlations of NF-κB to apoptotic markers. It is concluded that liraglutide protects cardiomyocytes against isoprenaline-induced apoptosis in experimental TT-like myocardial injury through downregulation of the NF-κB pathway.
Takotsubo syndrome (TTS) is an acute heart failure syndrome characterised by catecholamine-induced oxidative tissue damage. Punica granatum, a fruit-bearing tree, is known to have high polyphenolic content and has been proven to be a potent antioxidant. This study aimed to investigate the effects of pomegranate peel extract (PoPEx) pre-treatment on isoprenaline-induced takotsubo-like myocardial injury in rats. Male Wistar rats were randomised into four groups. Animals in the PoPEx(P) and PoPEx + isoprenaline group (P + I) were pre-treated for 7 days with 100 mg/kg/day of PoPEx. On the sixth and the seventh day, TTS-like syndrome was induced in rats from the isoprenaline(I) and P + I groups by administering 85 mg/kg/day of isoprenaline. PoPEx pre-treatment led to the elevation of superoxide dismutase and catalase (p < 0.05), reduced glutathione (p < 0.001) levels, decreased the thiobarbituric acid reactive substances (p < 0.001), H2O2, O2− (p < 0.05), and NO2− (p < 0.001), in the P + I group, when compared to the I group. In addition, a significant reduction in the levels of cardiac damage markers, as well as a reduction in the extent of cardiac damage, was found. In conclusion, PoPEx pre-treatment significantly attenuated the isoprenaline-induced myocardial damage, primarily via the preservation of endogenous antioxidant capacity in the rat model of takotsubo-like cardiomyopathy.
Background: Myocardial injury (MI) is characterized by an increased level of at least one cardiac troponin. Experimental MI can be induced by isoprenaline, a β-adrenergic agonist, and it can lead to heart failure (HF). Liraglutide is glucagon-like 1 peptide receptor agonist used in diabetes management, but it has anti-inflammatory and antioxidative effects, which can be beneficial in treatment of HF. The aim of this study was to investigate the effects of liraglutide on isoprenaline-induced MI and prevention of HF. Methods: Male Wistar albino rats were divided into four groups: Con—received saline the first 2 days + saline the next 7 days; Iso—isoprenaline the first 2 days + saline the next 7 days; Lir—saline the first 2 days + liraglutide the next 7 days; Iso + Lir—isoprenaline the first 2 days + liraglutide the next 7 days. On day 10, blood samples were taken for biochemical analysis and oxidative stress marker evaluation, and hearts were isolated for pathohistological analysis. Cardiac function was assessed by electrocardiography (ECG) and echocardiography (ECHO). Results: Liraglutide treatment significantly attenuated oxidative stress, repaired ECG and ECHO parameters, and mitigated myocardial morphological changes induced by isoprenaline. Conclusions: Liraglutide restores cardiac function in isoprenaline-induced HF.
As the leading cause of global mortality, cardiovascular diseases demand improved and innovative strategies for early detection and risk assessment to enhance prevention and timely treatment. This comprehensive review examines the potential of combining high-sensitivity cardiac troponins (hs-cTns) and homocysteine (Hcy) as complementary biomarkers for enhanced cardiovascular risk prediction. hs-cTn assays have revolutionized cardiovascular diagnostics by enabling the detection of minimal myocardial injury, improving early diagnosis of acute coronary syndrome, and providing robust prognostic information in both symptomatic and asymptomatic populations. Hcy, while established as a marker of vascular dysfunction, presents an interpretative challenge due to multiple confounding factors and inconsistent therapeutic responses. Emerging evidence demonstrates significant correlations between elevated Hcy and troponins across various clinical conditions, suggesting that their combined assessment—reflecting both myocardial injury and vascular dysfunction—may improve cardiovascular risk stratification. While initial findings are promising, additional studies are required to validate the clinical value of the combined marker approach. Future development of personalized interpretation algorithms, and multi-marker panels incorporating these biomarkers, may significantly advance cardiovascular medicine and enable more effective population-specific risk management strategies.