Complex interplay of DNA damage, DNA repair genes, and oxidative stress in coronary artery disease

Biochemical and toxicological effect of diazepam in stress-induced cardiac dysfunctions

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Evaluation of diazepam in stress-induced cardiac dysfunction in rats.

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Alteration of cardiac biomarkers and ionic concentrations by stress.

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Restoration of altered cardiac biomarkers and ionic concentrations by diazepam.

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Restoration of architectures of cardiomyocytes by diazepam.

Diazepam is a medicine of the family benzodiazepine, used to treat various CNS disorders. To date, no study is available for biochemical analysis of diazepam in cardiac dysfunction. This study aimed to determine the effect of diazepam in stress-induced cardiac dysfunctions in rats. Male Wistar Albino rats were divided into four groups with six animals in each group for 90 days of the experimental protocol. Group1 served as a Normal Control (NC), Groups 2, as a Disease Control (DC), Group 3 as a Diazepam Control (DIC), and Group 4 as a Disease + Diazepam Treatment (DDT). Disease Control and Disease + Diazepam Treatment animals exposed to regular stress by forced swimming exercise method for 3 months. Diazepam Control and Disease + Diazepam Treatment received 5 mg/kg/p.o the daily dose of diazepam. At the end of the protocol, animals were sacrificed, heart preserved, blood collected, and utilized for biochemical estimations. Heart weight was increased in DC as compared to NC. Serum levels of cardiac biomarkers, creatine phosphokinase (CPK), creatine kinase-MB (CPK-MB), lactate dehydrogenase (LDH), High sensitivity C-reactive protein (hs-CRP) and troponin I (TnI) were significantly increased in DC as compared to NC. Heart tissue examined for histological changes. The altered serum levels of CPK, CPK-MB, LDH, hs-CRP, and TnI were significantly restored by the treatment of diazepam. Serum levels of Sodium, Potassium, Calcium, and Magnesium was increased in DC animals as compared to NC. The altered ionic level was also restored by the treatment of diazepam. Level of various cardiac markers and ions in the plasma were also slightly elevated in DIC. Histopathological studies are also in agreement with serological examinations and bonafide cardioprotective influences of diazepam in cardiac dysfunction. Conclusively research findings endorse the cardioprotective effect of diazepam in stress-induced cardiac dysfunction in rats.

Epigenetics of Subcellular Structure Functioning in the Origin of Risk or Resilience to Comorbidity of Neuropsychiatric and Cardiometabolic Disorders

Mechanisms controlling mitochondrial function, protein folding in the endoplasmic reticulum (ER) and nuclear processes such as telomere length and DNA repair may be subject to epigenetic cues that relate the genomic expression and environmental exposures in early stages of life. They may also be involved in the comorbid appearance of cardiometabolic (CMD) and neuropsychiatric disorders (NPD) during adulthood. Mitochondrial function and protein folding in the endoplasmic reticulum are associated with oxidative stress and elevated intracellular calcium levels and may also underlie the vulnerability for comorbid CMD and NPD. Mitochondria provide key metabolites such as nicotinamide adenine dinucleotide (NAD+), ATP, α-ketoglutarate and acetyl coenzyme A that are required for many transcriptional and epigenetic processes. They are also a source of free radicals. On the other hand, epigenetic markers in nuclear DNA determine mitochondrial biogenesis. The ER is the subcellular organelle in which secretory proteins are folded. Many environmental factors stop the ability of cells to properly fold proteins and modify post-translationally secretory and transmembrane proteins leading to endoplasmic reticulum stress and oxidative stress. ER functioning may be epigenetically determined. Chronic ER stress is emerging as a key contributor to a growing list of human diseases, including CMD and NPD. Telomere loss causes chromosomal fusion, activation of the control of DNA damage-responses, unstable genome and altered stem cell function, which may underlie the comorbidity of CMD and NPD. The length of telomeres is related to oxidative stress and may be epigenetically programmed. Pathways involved in DNA repair may be epigenetically programmed and may contribute to diseases. In this paper, we describe subcellular mechanisms that are determined by epigenetic markers and their possible relation to the development of increased susceptibility to develop CMD and NPD.

Chemotherapeutic-Induced Cardiovascular Dysfunction: Physiological Effects, Early Detection-The Role of Telomerase to Counteract Mitochondrial Defects and Oxidative Stress

Although chemotherapeutics can be highly effective at targeting malignancies, their ability to trigger cardiovascular morbidity is clinically significant. Chemotherapy can adversely affect cardiovascular physiology, resulting in the development of cardiomyopathy, heart failure and microvascular defects. Specifically, anthracyclines are known to cause an excessive buildup of free radical species and mitochondrial DNA damage (_mtDNA) that can lead to oxidative stress-induced cardiovascular apoptosis. Therefore, oncologists and cardiologists maintain a network of communication when dealing with patients during treatment in order to treat and prevent chemotherapy-induced cardiovascular damage; however, there is a need to discover more accurate biomarkers and therapeutics to combat and predict the onset of cardiovascular side effects. Telomerase, originally discovered to promote cellular proliferation, has recently emerged as a potential mechanism to counteract mitochondrial defects and restore healthy mitochondrial vascular phenotypes. This review details mechanisms currently used to assess cardiovascular damage, such as C-reactive protein (CRP) and troponin levels, while also unearthing recently researched biomarkers, including circulating _mtDNA, telomere length and telomerase activity. Further, we explore a potential role of telomerase in the mitigation of mitochondrial reactive oxygen species and maintenance of _mtDNA integrity. Telomerase activity presents a promising indicator for the early detection and treatment of chemotherapy-derived cardiac damage.