Cardiac tissue oxidative stress and inflammation after vitamin D administrations in high fat- diet induced obese rats

Vitamin D Alleviates Heavy Metal-Induced Cytotoxic Effects on Human Bone Osteoblasts Via the Induction of Bioenergetic Disruption, Oxidative Stress, and Apoptosis

Cadmium (Cd) and lead (Pb) are heavy metals (HMs) that persistently contaminate the ecosystem, and bioaccumulation in bones is a health concern. We used biochemical and molecular assays to assess the cytoprotective effect of vitamin D (VD) on Cd- and Pd-induced chemical toxicity of human bone osteoblasts in vitro. Exposing Cd and Pb to human osteoblast cultures at concentrations of 0.1-1000 µM for 24-72 h significantly reduced osteoblast viability in an exposure time- and concentration-dependent manner. The cytotoxic effect of Cd on osteoblasts was more severe than Pb's, with 72-h exposure estimated half maximal effective concentration (EC50) of 8 and 12 µM, respectively, and VD (1 and 10 nM) alleviated cytotoxicity. Bioenergetics assays of ATP, mitochondrial membrane potential, and mitochondrial complex I and III activity showed that both Cd and Pb (1 and 10 µM) inhibited cellular bioenergetics after 72-h exposure. Cd and Pb increased lipid peroxidation and reactive oxygen species with reduced catalase/superoxide dismutase antioxidant activities and increased activity of caspases -3, -8, and -9. Co-treatment with VD (1 and 10 nM) counteracted bioenergetic disruption, oxidative damage, and apoptosis in a concentration-dependent manner. These findings suggest that VD is effective in managing the toxic effects of environmental pollutants and in treating bone diseases characterized by oxidative stress, apoptosis, and bioenergetic disruption.

Artesunate attenuates isoprenaline induced cardiac hypertrophy in rats via SIRT1 inhibiting NF-κB activation

Cardiac Hypertrophy is an adaptive response of the body to physiological and pathological stimuli, which increases cardiomyocyte size, thickening of cardiac muscles and progresses to heart failure. Downregulation of SIRT1 in cardiomyocytes has been linked with the pathogenesis of cardiac hypertrophy. The present study aimed to investigate the effect of Artesunate against isoprenaline induced cardiac hypertrophy in rats via SIRT1 inhibiting NF-κB activation. Experimental cardiac hypertrophy was induced in rats by subcutaneous administration of isoprenaline (5 mg/kg) for 14 days. Artesunate was administered simultaneously for 14 days at a dose of 25 mg/kg and 50 mg/kg. Artesunate administration showed significant dose dependent attenuation in mean arterial pressure, electrocardiogram, hypertrophy index and left ventricular wall thickness compared to the disease control group. It also alleviated cardiac injury biomarkers and oxidative stress. Histological observation showed amelioration of tissue injury in the artesunate treated groups compared to the disease control group. Further, artesunate treatment increased SIRT1 expression and decreased NF-kB expression in the heart. The results of the study show the cardioprotective effect of artesunate via SIRT1 inhibiting NF-κB activation in cardiomyocytes.

Effect of caffeine-chitosan nanoparticles and α-lipoic acid on the cardiovascular changes induced in rat model of obesity

The current research aims to study the therapeutic efficacy of alpha-lipoic acid (α-LA) and caffeine-loaded chitosan nanoparticles (Caf-CNs) against cardiovascular complications induced by obesity. Rats were divided randomly into: control, high fat diet (HFD) induced obesity rat model, obese rats treated with α-LA and/or Caf-CNs. Triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), Interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) as well as activities of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) significantly increased in the serum of obese rats. In addition, plasma atherogenic index, atherogenic coefficient and Castelli's risk indices I and II showed a significant increase. Additionally, levels of malondialdehyde (MDA) and nitric oxide (NO) and activity of monoamine oxidase (MAO) were significantly elevated in heart tissues of obese rats. However, cardiac Na+/K+-ATPase and acetylcholinesterase (AchE) activities and reduced glutathione (GSH), serotonin (5-HT), norepinephrine (NE) and dopamine (DA) as well as serum high-density lipoprotein cholesterol (HDL-C) were significantly reduced in obese rats. Treatment with α-LA and/or Caf-CNs ameliorated almost all the biochemical and histopathological alterations caused by obesity. In conclusion, the present data revealed that α-LA and/or Caf-CNs may be an effective therapeutic approach against cardiac complications caused by obesity through their antilipemic, anti-atherogenic, antioxidant, and anti-inflammatory activities.

Possibilities of dapagliflozin-induced cardioprotection on doxorubicin + cyclophosphamide mode of chemotherapy-induced cardiomyopathy

RATIONALE

The global burden of cardiovascular (CV) and oncological diseases continues to increase. In this regard, the prevention of CV diseases (CVD) before and after cancer treatment is an urgent and unsolved problem in medicine. For this reason, our research group aimed to investigate the possibility of dapagliflozin-related cardioprotection, using an experimental model of chronic Doxorubicin (Adriamycin) + Cyclophosphamide (AC)-mode of chemotherapy-induced cardiomyopathy.

OBJECTIVE

The redox balance, lipid metabolism, endothelial dysfunction, and myocardial damage parameters were measured to evaluate the pathways of dapagliflozin-induced stabilization of CV homeostasis.

METHODS

For this study, 80 inbred Wistar rats were randomly assigned to four equally sized groups. A model of chronic cardiotoxicity was attained by using doxorubicin and cyclophosphamide co-administration. In the case, the markers of redox-balance, cholesterol metabolism, endothelial dysfunction, myocardial alteration, and morphological examination were assessed.

RESULTS

For all parameters, statistically significant deviations were obtained, emphasizing the sequel of AC-mode chemotherapy-related detergent effect on CV system (group 2). Moreover, the data obtained from dapagliflozin-treated groups (group 3) showed that this strategy provide limitation of lipid peroxidation, cholesterol metabolism and endothelial function normalization, with subsequent morphological preservation of myocardium.

CONCLUSION

Dapagliflozin has a broad spectrum of pleiotropic influences, namely cholesterol-lowering, anti-inflammatory, and endothelium-stabilizing properties. These properties provide a favorable environment for the prevention of chemotherapy-related cardiomyopathy.

Reactive oxygen species, toxicity, oxidative stress, and antioxidants: chronic diseases and aging

A physiological level of oxygen/nitrogen free radicals and non-radical reactive species (collectively known as ROS/RNS) is termed oxidative eustress or "good stress" and is characterized by low to mild levels of oxidants involved in the regulation of various biochemical transformations such as carboxylation, hydroxylation, peroxidation, or modulation of signal transduction pathways such as Nuclear factor-κB (NF-κB), Mitogen-activated protein kinase (MAPK) cascade, phosphoinositide-3-kinase, nuclear factor erythroid 2-related factor 2 (Nrf2) and other processes. Increased levels of ROS/RNS, generated from both endogenous (mitochondria, NADPH oxidases) and/or exogenous sources (radiation, certain drugs, foods, cigarette smoking, pollution) result in a harmful condition termed oxidative stress ("bad stress"). Although it is widely accepted, that many chronic diseases are multifactorial in origin, they share oxidative stress as a common denominator. Here we review the importance of oxidative stress and the mechanisms through which oxidative stress contributes to the pathological states of an organism. Attention is focused on the chemistry of ROS and RNS (e.g. superoxide radical, hydrogen peroxide, hydroxyl radicals, peroxyl radicals, nitric oxide, peroxynitrite), and their role in oxidative damage of DNA, proteins, and membrane lipids. Quantitative and qualitative assessment of oxidative stress biomarkers is also discussed. Oxidative stress contributes to the pathology of cancer, cardiovascular diseases, diabetes, neurological disorders (Alzheimer's and Parkinson's diseases, Down syndrome), psychiatric diseases (depression, schizophrenia, bipolar disorder), renal disease, lung disease (chronic pulmonary obstruction, lung cancer), and aging. The concerted action of antioxidants to ameliorate the harmful effect of oxidative stress is achieved by antioxidant enzymes (Superoxide dismutases-SODs, catalase, glutathione peroxidase-GPx), and small molecular weight antioxidants (vitamins C and E, flavonoids, carotenoids, melatonin, ergothioneine, and others). Perhaps one of the most effective low molecular weight antioxidants is vitamin E, the first line of defense against the peroxidation of lipids. A promising approach appears to be the use of certain antioxidants (e.g. flavonoids), showing weak prooxidant properties that may boost cellular antioxidant systems and thus act as preventive anticancer agents. Redox metal-based enzyme mimetic compounds as potential pharmaceutical interventions and sirtuins as promising therapeutic targets for age-related diseases and anti-aging strategies are discussed.

Cardiovascular complications are resolved by tuna protein hydrolysate supplementation in rats fed with a high-fat diet

This study is aimed to investigate whether tuna protein hydrolysate (TPH) supplementation could alleviate cardiovascular complications induced by a high-fat diet (HFD) in rats. Rats were fed a HFD for 16 weeks and given TPH (100 mg/kg, 300 mg/kg, or 500 mg/kg) or metformin (100 mg/kg) (n = 8) for the last four weeks. TPH had the following effects: resolved their impaired glucose tolerance, hyperglycemia, dyslipidemia, obesity, and hypertension (p < 0.05); alleviated left ventricular dysfunction and hypertrophy (p < 0.05), and vascular dysfunction and hypertrophy (p < 0.05); adipocyte hypertrophy; increases in circulating leptin and tumor necrosis factor (TNF-α) were mitigated (p < 0.05); increased renin-angiotensin system (RAS), oxidative stress, and decreased nitric oxide metabolites were modulated (p < 0.05). TPH restored the expression of angiotensin II receptor type 1 (AT1R)/NADPH oxidase 2 (NOX2), endothelial nitric oxide synthase (eNOS), nuclear factor erythroid 2-related factor (Nrf2)/heme oxygenase-1 (HO-1), and peroxisome proliferator-activated receptor γ (PPARγ)/the nuclear factor kappa B (NF-κB) protein in cardiovascular tissue (p < 0.05). In metabolic syndrome (MS) rats, metformin and TPH had comparable effects. In conclusion, TPH alleviated cardiovascular complications related to MS. It suppressed RAS, oxidative stress, and inflammation that were associated with modulation of AT1R/NOX2, eNOS, Nrf2/HO-1, and PPARγ/NF-κB expression.

Vitamin D3 alleviates nonalcoholic fatty liver disease in rats by inhibiting hepatic oxidative stress and inflammation via the SREBP-1-c/ PPARα-NF-κB/IR-S2 signaling pathway

Introduction: Nonalcoholic fatty liver disease (NAFLD) is a chronic disease characterized by fat deposits in liver cells, which can lead to hepatitis and fibrosis. This study attempted to explore the protective effect of vitamin D3 (VitD) against NAFLD. Methods: Adult male albino rats were randomized into four separate groups: the negative control group was fed a standard rat chow; the positive group received a high-fat diet (20%) and 25% fructose water (NAFLD); the VitD control group was intramuscularly treated with VitD (1,000 IU/kg BW) 3 days per week for 10 weeks; and the NAFLD group was treated with VitD therapy. Biochemical and hepatic histological analyses were performed. Hepatic oxidative stress and inflammatory conditions were also studied. Hepatic expression of sterol regulatory element-binding protein 1-c (SREBP-1-c), peroxisome proliferator-activated receptor alpha (PPAR-α), and insulin receptor substrate-2 was analyzed by quantitative real-time polymerase chain reaction. Results and discussion: The NAFLD rats exhibited elevated terminal body weight, hepatic injury markers, dyslipidemia, glucose intolerance, and insulin resistance. Moreover, the NAFLD rats had increased SREBP-1-c expression and reduced PPAR-α and IRS-2 expressions. Histological analysis showed hepatic steatosis and inflammation in the NAFLD group. In contrast, VitD administration improved the serum biochemical parameters and hepatic redox status in NAFLD rats. Also, VitD treatment ameliorated hepatic inflammation and steatosis in the NAFLD group by decreasing the expression of SREBP-1-c and increasing the expression of PPAR-α. Overall, these results suggest that VitD could have a protective effect against NAFLD and its associated complication.

Effects of Taraxerol on Oxidative and Inflammatory Mediators in Isoproterenol-Induced Cardiotoxicity in an Animal Model

Myocardial infarction (MI) continues to be an important issue in healthcare systems worldwide, leading to high rates of morbidity and mortality. Despite ongoing efforts towards the development of preventive measures and treatments, addressing the challenges posed by MI remains difficult both in developed and developing countries. However, researchers recently investigated the potential cardioprotective effects of taraxerol utilizing an isoproterenol (ISO)-induced cardiotoxicity model among Sprague Dawley rats. Specifically, subcutaneous tissue injections consisting of 5.25 mg/kg or 8.5 mg/kg ISO were administered over two consecutive days as stimuli to induce cardiac injury. To investigate the possibility of preventing damage caused by ISO-induced cardiotoxicity by taraxerol treatment, five groups were formed: a normal control group (1% Tween 80), an ISO control group, an amlodipine group administered 5 mg/kg/day, and various doses of taraxerol. The study results showed that treatment significantly reduced cardiac marker enzymes. Additionally, pretreatment with taraxerol increased myocardial activity in SOD and GPx, leading to significant reductions in serum CK-MB levels along with MDA, TNF-α, and IL-6. Further histopathological analysis supported these observations, as treated animals had less cellular infiltration compared to untreated ones. These multifaceted findings suggest that oral administration of taraxerol could potentially protect hearts from ISO-caused damage by increasing endogenous antioxidant concentrations while decreasing pro-inflammatory cytokines.

Vitamin D supplementation and cardiac tissue inflammation in obese rats

OBJECTIVE

The current study was aimed to evaluate the effects of active form of vitamin D on TGF- β, NF-κB and MCP-1 in heart tissue of obese rats.

METHODS

Forty rats were allocated into groups of normal diet and high fat diet for sixteen weeks; then each group was divided into two groups that received either 500 IU/kg vitamin D or placebo for five weeks. Biochemical parameters were assessed by ELISA kits.

RESULTS

Vitamin D reduced TGF-β in obese rats supplemented with vitamin D compared with other groups (P = 0.03). Moreover, vitamin D reduced MCP-1 concentrations in the heart tissues of both vitamin D administered groups compared to placebo one (P = 0.002). NF-κB in the heart of HFD + vitamin D group was significantly lower (P = 0.03). Current study also showed that vitamin D improves glycemic status and reduce insulin resistance significantly in HFD group (P = 0.008).

CONCLUSION

Vitamin D was a potential anti- inflammatory mediator of cardiovascular disease and markers of glycemic status in obese rats. Further investigations are needed to better identify the therapeutic role of this vitamin in CVD and to elucidate the underlying mechanisms.

Treadmill exercise training improves the high-fat diet-induced behavioral changes in the male rats

The purpose of this study was to investigate the effects of treadmill exercise training on obesity-induced behavioral changes in high-fat diet (HFD)-induced male rats. In this study, 40 male Sprague-Dawley rats were divided into 4 groups after they were weaned: Control (C), Exercise (E), Obese (O) and Obese + Exercise (O + E). For the obesity model % 60 high-fat diet were applied. After obesity was induced, rats were either moderate aerobic exercise (treadmill running) trained or left untrained. Different tasks to assess spatial learning and memory (Morris water maze test (MWMT)), depressive-like behavior (forced swimming test(FST), tail suspension test (TST) and anxiety-like behavior (light-dark test (LDT) and open field test (OFT)) were conducted. Exercise caused a significant reduction in duration of immobility in the O group in FST and the decrease in immobility in the O + E rats in TST. The O + E rats demonstrated a significant increase in the time spent in the light box as compared to the O group in the LDT. The O + E rats did not show any behavioral alterations as compared to all the other groups in the OFT. In the O + E group, there was a significant increase in the time spent in the target quadrant compared to the O group in the MWMT. Our results support that treadmill exercise could improve cognitive, depressive-like, anxiety-like behavioral changes in the HFD-induced obese rats.

Chrysin reduces hypercholesterolemia-mediated atherosclerosis through modulating oxidative stress, microflora, and apoptosis in experimental rats

Chrysin (Chy) is known for various biological proprieties such as inhibitory effects on inflammation, cancer, oxidative stress, aging, and atherosclerosis. However, the hypolipidemic activity of Chy and its mechanistic action remains unclear in cardiovascular diseases (CVD). In this study, we focused on the hypolipidemic proprieties of Chy in hypercholesterolemia-induced atherosclerosis. Male Wistar rats (150-220 g) were divided into four groups as follows: Group I control was fed with standard laboratory chow. Rats in Group II were fed a high-fat diet (HFD) for 60 days. After 60 days of HFD, Group III rats received Chy (100 mg/kg body weight); Group IV rats received Atorvastatin (Atv; 10 mg/kg body weight) for 30 days. Biochemical studies showed Chy, Atv treatment decreased the activities of liver marker enzymes and the levels of Reactive Oxygen Species (ROS) and lipid profile. Gene expression analysis on nuclear factor erythroid 2-related factor 2 (Nrf2) and its regulated genes were significantly reduced in the intestine and increased in the aorta by Chy and Atv. Gut microbial species such as Bacteroidetes, Lactobacillus, Enterococcus, and Clostridium leptum copy numbers were significantly increased by Chy and Atv treatment. In addition, Chy and Atv modulated the expression of inflammatory genes including TLR4, TNFα, NLRP3, and IL-17 in the aorta and intestine compared with hypercholesterolemic control rats. Chy and Atv effectively increased the caspase-3 mRNA expression in the intestine, but these decreased in the aorta. The present study concludes that by reducing oxidative stress and increasing gut microbial colonization, Chy may provide an effective therapeutic approach for the prevention of hypercholesterolemia-mediated atherosclerosis. PRACTICAL APPLICATIONS: Our study focused on a therapeutic model representing the clinical presentation of atherosclerosis in humans. Statins are commonly used in the treatment of cardiovascular complications, patients with hypercholesterolemia face difficulties in the continuation of statin therapy. The reason for statin discontinuation has been associated with toxicological effects. It is necessary to investigate the potentiality of the natural compound as an alternative medicine to statin with fewer side effects. The main theme of our study is to compare the therapeutic potential of Chy and Atv. Chy is a natural bioflavonoid that could be considered as an alternative medicinal compound to statins and to avoid toxicity problems associated with statins. Chy is a bioflavonoid present in Passiflora caerulea (blue passion flower), Oroxylum indicum (Indian trumpet flower), Pelargonium crispum, propolis, and honey. Consuming Chy-rich foods will reduce hypercholesterolemia-mediated cardiovascular complications. Overall, the present studies provided a key to developing bioactive compounds-based foods for CVD patients.

Interrelationship between Vitamin D and Calcium in Obesity and Its Comorbid Conditions

Obesity has been linked to vitamin D (VD) deficiency and low calcium (CAL) status. In the last decade, dietary supplementation of vitamin D and calcium (VD-CAL) have been extensively studied in animal experiments and human studies. However, the physiological mechanisms remain unknown as to whether the VD-CAL axis improves homeostasis and reduces biomarkers in regulating obesity and other metabolic diseases directly or indirectly. This review sought to investigate their connections. This topic was examined in scientific databases such as Web of Science, Scopus, and PubMed from 2011 to 2021, and 87 articles were generated for interpretation. Mechanistically, VD-CAL regulates from the organs to the blood, influencing insulin, lipids, hormone, cell, and inflammatory functions in obesity and its comorbidities, such as non-alcoholic fatty liver disease, cardiovascular disease, and type-2 diabetes mellitus. Nevertheless, previous research has not consistently shown that simultaneous VD-CAL supplementation affects weight loss or reduces fat content. This discrepancy may be influenced by population age and diversity, ethnicity, and geographical location, and also by degree of obesity and applied doses. Therefore, a larger prospective cohort and randomised trials are needed to determine the exact role of VD-CAL and their interrelationship.

Raspberry and blackberry act in a synergistic manner to improve cardiac redox proteins and reduce NF-κB and SAPK/JNK in mice fed a high-fat, high-sucrose diet

BACKGROUND AND AIMS

Increased cardiac inflammation and oxidative stress are common features in obesity, and toll-like receptor (TLR)4 signaling is a key inflammatory pathway in this deleterious process. This study aimed to investigate whether berries could attenuate the detrimental effects of a high-fat, high-sucrose (HFHS) diet on the myocardium at the molecular level.

METHODS AND RESULTS

Eight-week-old male C57BL/6 mice consumed a low-fat, low-sucrose (LFLS) diet alone or supplemented with 10% blackberry (BL), 10% raspberry (RB) or 10% blackberry + raspberry (BL + RB) for four weeks. Animals were then switched to a HFHS diet for 24 weeks with or without berry supplementation or maintained on a LFLS control diet without berry supplementation. Left ventricles of the heart were isolated for protein and mRNA analysis. Berry consumption, particularly BL + RB reduced NADPH-oxidase (NOX)1 and NOX2 and increased catalase (CAT) and superoxide dismutase (SOD)2, expression while BL and RB supplementation alone was less efficacious. Downstream TLR4 signaling was attenuated mostly by both RB and BL + RB supplementation, while NF-κB pathway was attenuated by BL + RB supplementation. Stress-activated protein kinase (SAPK)/Jun amino-terminal kinase (JNK) was also attenuated by BL + RB supplementation, and reduced TNF-α transcription and protein expression was observed only with BL + RB supplementation.

CONCLUSION

The synergistic effects of BL + RB may reduce obesity-induced cardiac inflammation and oxidative stress to a greater extent than BL or RB alone.

Adrenomedullin Improves Cardiac Remodeling and Function in Obese Rats with Hypertension

This study aimed to determine whether adrenomedullin (ADM, 7.2 μg/kg/day, ip), an important endogenous active peptide, has a protective role in cardiac remodeling and function in obesity-related hypertension (OH) rats. A high-fat diet (HFD) was used to induce OH for 20 weeks. H9c2 cells incubated with palmitate (PA, 200 μM) to mimic high free fatty acid in obesity were used as an in vitro model. In OH rats, ADM not only decreased body weight (BW) and blood pressure (BP) but also improved systemic inflammation and oxidative stress. Moreover, ADM still had a greater inhibitory effect on local inflammation and oxidative stress in the hearts of OH rats, and the same anti-inflammatory and antioxidant effects were also confirmed in PA-treated H9c2 cells. The ADM receptor antagonist or Akt inhibitor effectively attenuated the inhibitory effects of ADM on inflammation and oxidative stress in PA-stimulated H9c2 cells. Furthermore, ADM application effectively normalized heart function, and hematoxylin-eosin and Masson staining and collagen volume fraction results showed that ADM improved cardiac remodeling in hearts of OH rats. ADM attenuated cardiac inflammation and oxidative stress via the receptor-Akt pathway, which involves the improvement of cardiac remodeling and function in OH rats.

Vitamin D3 intake as modulator for the early biomarkers of myocardial tissue injury in diabetic hyperlipidaemic rats

CONTEXT

Myocardial cell death occurs within hours following the onset of myocardial ischaemia and its chief cause is atherosclerosis. There is a link between vitamin D3 deficiency and many cardiovascular risk factors.

OBJECTIVE

This study compared the effect of vitamin D3 on early biomarkers of myocardial injury, to that of atorvastatin.

METHODS

Diabetic hyperlipidaemia was induced in Wistar rats, which were divided into 3 groups: diabetic hyperlipidaemic control, diabetic hyperlipidaemic rats treated with atorvastatin and diabetic hyperlipidaemic rats treated with vitamin D3. Blood glucose, glycated haemoglobin and lipid profile were evaluated. Markers of myocardial injury were examined including cardiac troponin, heart fatty acid binding protein (HFABP) and C-terminal pro-endothelin-1 (CT-pro-ET-1).

RESULTS

Vitamin D3 and atorvastatin intake improved lipid profile and glucose homeostasis, and reduced levels of predictive biomarkers of myocardial injury.

CONCLUSION

Vitamin D3 can be used in a suitable dose as a safe and protective candidate against myocardial injury.

Time-Restricted Feeding Improved Vascular Endothelial Function in a High-Fat Diet-Induced Obesity Rat Model

Obesity, where there is enhancement of stored body fat in adipose tissues, is associated with cardiovascular complications that are mainly related to atherosclerosis. Time-restricted feeding (TRF) is a form of restricted eating aimed at reducing weight in obese subjects. The present study aims to investigate changes in vascular endothelial function, endothelial nitric oxide synthase (eNOS), and protein kinase B (Akt) protein expressions with TRF in obese and normal rats. Male Sprague Dawley rats were divided into two normal and three obese groups; obesity was induced in the obese groups by feeding with a high-fat diet (HFD) for six weeks. After six weeks, rats were equally divided into five groups (n = 7 per group): Normal group (NR) which continued on a standard diet for six more weeks, normal group switched to TRF with a standard diet for six weeks (NR + TRFSD), obese group (OR) which continued on HFD for six more weeks, obese group switched to TRF of HFD (OR + TRFHFD), and obese group switched to TRF of a standard diet (OR + TRFSD). TRF was practiced for six weeks, after which the rats were sacrificed. Aortic endothelium-dependent and endothelium-independent relaxations and contractions were assessed using the organ bath. Aortic eNOS and Akt protein expressions were determined using immunoblotting. Fasting blood glucose, body weight, body mass index (BMI), serum lipid profile, Lee’s index, serum insulin levels, and sensitivity (HOMA-IR) were also measured. Endothelium-dependent relaxation was significantly impaired, while endothelium-dependent contraction increased in obese rats compared to that in normal rats. Both obese groups which underwent TRF with a HFD and standard diet improved their impairments in endothelium-dependent relaxation and reduced endothelium-dependent contraction; these were associated with increased expressions of aortic eNOS and Akt protein. Both obese groups with TRF reduced body weight, BMI, Lee’s index, total cholesterol, triglycerides, low-density lipoprotein cholesterol, and improved insulin sensitivity. TRF improved endothelium-dependent relaxation and reduced endothelium-dependent contraction, thus attenuating endothelial dysfunction in obese rats. These were associated with increased aortic eNOS and Akt protein expressions.

Antioxidant enzymes and vascular diseases

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) play a fundamental role in regulating endothelial function and vascular tone in the physiological conditions of a vascular system. However, oxidative stress has detrimental effects on human health, and numerous studies confirmed that high ROS/RNS production contributes to the initiation and progression of cardiovascular diseases. The antioxidant defense has an essential role in the homeostatic functioning of the vascular endothelial system. Endogenous antioxidative defense includes various molecules and enzymes such as superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase. Together all these antioxidative enzymes are essential for defense against harmful ROS features. ROS are mainly generated from redox-active compounds involved in the mitochondrial respiratory chain. Thus, targeting antioxidative enzymes and mitochondria oxidative balance may be a promising approach for vascular diseases occurrence and treatment. This review summarized the most recent research on the regulation of antioxidative enzymes in vascular diseases.

The effects of consuming a low-fat yogurt fortified with nano encapsulated vitamin D on serum pro-oxidant-antioxidant balance (PAB) in adults with metabolic syndrome; a randomized control trial

BACKGROUND AND AIM

The current study aimed to assess the effect of fortified yogurt with nano-encapsulated vitamin D on serum pro-oxidant anti-oxidant balance (PAB) in adults with or without metabolic syndrome.

METHODS

In a quadruple blind clinical trial study, 139 adults with an age range of 30-50 years were randomly selected to receive either 1500 IU nano-encapsulated vitamin D fortified yogurt or placebo for ten weeks. Before and after the intervention period, blood sample was taken to determine the serum levels of vitamin D, pro-oxidant-antioxidant balance (PAB), and high-sensitivity C-reactive protein (hs-CRP). The laboratory tests were checked at baseline and at the end of the treatment.

RESULTS

Serum vitamin D increased significantly, from 14.47 ± 6.07 ng/mL to 21.39 ± 6.54 ng/mL (P < 0.001) after ten weeks in the intervention group. Serum hs-CRP and PAB were significantly lower following consumption period in intervention group [1.95(0.4-8.15) g/dL vs. 1.35(0.25-3.62) g/dL; P = 0.013] and (135.19 ± 42.4 HK vs. 115.39 ± 44.69) HK; P = 0.018] respectively. There were no significant differences between the intervention and control groups regarding weight and BMI at the end of the intervention period (p > 0.05).

CONCLUSION

Low-fat yogurt fortified with nano-encapsulated vitamin D was found to reduce serum PAB levels in adults with metabolic syndrome.

PRACTICAL APPLICATION

The findings of the present study indicated that a low-fat yogurt fortified with 1500 IU nano-encapsulated vitamin D for ten weeks, leads to a significant reduction in serum hs-CRP and PAB concentrations highlighted the anti-inflammatory/anti-oxidative effect of vitamin D.

Effectiveness of Some Vitamins in the Prevention of Cardiovascular Disease: A Narrative Review

By virtue of their regulatory role in various metabolic and biosynthetic pathways for energy status and cellular integrity, both hydro-soluble and lipo-soluble vitamins are considered to be involved in maintaining cardiovascular function in health and disease. Deficiency of some vitamins such as vitamin A, B₆, folic acid, C, D, and E has been shown to be associated with cardiovascular abnormalities whereas supplementation with these vitamins has been claimed to reduce cardiovascular risk for hypertension, atherosclerosis, myocardial ischemia, arrhythmias, and heart failure. However, the data from several experimental and clinical studies for the pathogenesis of cardiovascular disease due to vitamin deficiency as well as therapy due to different vitamins are conflicting. In this article, we have attempted to review the existing literature on the role of different vitamins in cardiovascular disease with respect to their deficiency and supplementation in addition to examining some issues regarding their involvement in heart disease. Although both epidemiological and observational studies have shown some merit in the use of different antioxidant vitamins for the treatment of cardiovascular disorders, the results are not conclusive. Furthermore, in view of the complexities in the mechanisms of different cardiovascular disorders, no apparent involvement of any particular vitamin was seen in any specific cardiovascular disease. On the other hand, we have reviewed the evidence that deficiency of vitamin B₆ promoted KCl-induced Ca²⁺ entry and reduced ATP-induced Ca²⁺-entry in cardiomyocytes in addition to decreasing sarcolemmal (SL) ATP binding. The active metabolite of vitamin B₆, pyridoxal 5′-phosphate, attenuated arrhythmias due to myocardial infarction (MI) as well as cardiac dysfunction and defects in the sarcoplasmic reticulum (SR) Ca²⁺-transport in the ischemic-reperfused hearts. These observations indicate that both deficiency of some vitamins as well as pretreatments with different vitamins showing antioxidant activity affect cardiac function, metabolism and cation transport, and support the view that antioxidant vitamins or their metabolites may be involved in the prevention rather than the therapy of cardiovascular disease.

Vitamin D3 Supplementation Alleviates Left Ventricular Dysfunction in a Mouse Model of Diet-Induced Type 2 Diabetes: Potential Involvement of Cardiac Lipotoxicity Modulation

PURPOSE

To evaluate the effectiveness of vitamin D₃ supplementation, in secondary prevention, on cardiac remodeling and function, as well as lipid profile, in a mouse model of diet-induced type 2 diabetes.

METHODS

Mice were fed a high fat and sucrose diet for 10 weeks. Afterward, diet was maintained for 15 more weeks and two groups were formed, with and without cholecalciferol supplementation. A control group was fed with normal chow. Glucose homeostasis and cardiac function were assessed at baseline and at the 10th and 24th weeks. Animals were killed at the 10th and 25th weeks for plasma and cardiac sample analysis. Cardiac lipid profile was characterized by LC-MS/MS.

RESULTS

After 10 weeks of diet, mice exhibited pre-diabetes, mild left ventricle hypertrophy, and impaired longitudinal strain, but preserved myocardial circumferential as well as global diastolic and systolic cardiac function. After 15 more weeks of diet, animals presented with well-established type 2 diabetes, pathological cardiac hypertrophy, and impaired regional myocardial function. Cholecalciferol supplementation had no effect on glucose homeostasis but improved cardiac remodeling and regional myocardial function. After 25 weeks, non-supplemented mice exhibited increased myocardial levels of ceramides and diacylglycerol, both of which were normalized by vitamin D₃ supplementation.

CONCLUSION

This work brought to light the beneficial effects of cholecalciferol supplementation, in secondary prevention, on cardiac remodeling and function in a mouse model of diet-induced type 2 diabetes. Those cardioprotective effects may be, at least in part, attributed to the modulation of myocardial levels of lipotoxic species by vitamin D.

Molecules and Mechanisms to Overcome Oxidative Stress Inducing Cardiovascular Disease in Cancer Patients

Reactive oxygen species (ROS) are molecules involved in signal transduction pathways with both beneficial and detrimental effects on human cells. ROS are generated by many cellular processes including mitochondrial respiration, metabolism and enzymatic activities. In physiological conditions, ROS levels are well-balanced by antioxidative detoxification systems. In contrast, in pathological conditions such as cardiovascular, neurological and cancer diseases, ROS production exceeds the antioxidative detoxification capacity of cells, leading to cellular damages and death. In this review, we will first describe the biology and mechanisms of ROS mediated oxidative stress in cardiovascular disease. Second, we will review the role of oxidative stress mediated by oncological treatments in inducing cardiovascular disease. Lastly, we will discuss the strategies that potentially counteract the oxidative stress in order to fight the onset and progression of cardiovascular disease, including that induced by oncological treatments.

The relationship between vitamin D deficiency and oxidative stress can be independent of age and gender

Abstract. The active vitamin D (1,25(OH)2D) acts through a nuclear receptor to perform several functions in cellular metabolism. 1,25(OH)2D participates directly in calcium homeostasis, regulates the immune system, nervous system, blood pressure, insulin secretion, among others. Vitamin D deficiency could also be associated with several diseases and increased cellular oxidative damage. The present study aimed to investigate whether lipid peroxidation and/or protein oxidation are affected by vitamin D deficiency and whether sunlight exposure/diet, gender, and age might influence this relationship. Vitamin D concentrations were obtained from the Heart Hospital database and a questionnaire was applied among the 212 participants. We used the inactive vitamin D (25(OH)2) in the analyses since 1,25(OH)2D has a short half-life and a low blood concentration. Lipid peroxidation and protein oxidation analyses were performed using spectrophotometry. Multivariate analyses suggested the participation of vitamin D deficiency (<30 ng/mL) and sunlight/diet in oxidative stress (p <0.05; R2 MDA: 0.562; R2 CG: 0.429). Multiple linear regression test show that the age and gender of patients are not interfering in the analyses (p>0.05). Therefore, we suggest that the relationship between vitamin D deficiency and oxidative stress can be independent of age and gender.

Vitamin D deficiency exacerbates Alzheimer-like pathologies by reducing antioxidant capacity

Vitamin D (VD) deficiency is prevalent among aging people and Alzheimer's disease (AD) patients. However, the roles of VD deficiency in the pathology of AD remain largely unexplored. In this study, APP/PS1 mice were fed a VD-deficient diet for 13 weeks to evaluate the effects of VD deficiency on the learning and memory functions and the neuropathological characteristics of the mice. Our study revealed that VD deficiency accelerated cognitive impairment in the APP/PS1 mice. Mechanistic studies revealed that VD deficiency promoted glial activation and increased inflammatory factor secretion. Furthermore, VD deficiency increased the production and deposition of Aβ by elevating the expression levels of amyloid precursor protein (APP) and β-site APP cleavage enzyme 1 (BACE1). In addition, VD deficiency increased the phosphorylation of Tau at Thr181, Thr205 and Ser396 by increasing the activities of cyclin-dependent kinase 5 (CDK5) and glycogen synthase kinase 3α/β (GSK3α/β) and promoted synaptic dystrophy and neuronal loss. All these effects of VD deficiency may be ascribed to enhanced oxidative stress via the downregulation of superoxide dismutase 1 (SOD1), glutathione peroxidase 4 (GPx4) and cystine/glutamate exchanger (xCT). Taken together, our data suggest that VD deficiency exacerbates Alzheimer-like pathologies via promoting inflammatory stress, increasing Aβ production and elevating Tau phosphorylation by decreasing antioxidant capacity in the brains of APP/PS1 mice. Hence, rescuing the VD status of AD patients should be taken into consideration during the treatment of AD.

Oxidative Stress in Cardiovascular Diseases

Reactive oxygen species (ROS) are subcellular messengers in signal transductions pathways with both beneficial and deleterious roles. ROS are generated as a by-product of mitochondrial respiration or metabolism or by specific enzymes such as superoxide dismutases, glutathione peroxidase, catalase, peroxiredoxins, and myeloperoxidases. Under physiological conditions, the low levels of ROS production are equivalent to their detoxification, playing a major role in cellular signaling and function. In pathological situations, particularly atherosclerosis or hypertension, the release of ROS exceeds endogenous antioxidant capacity, leading to cell death. At cardiovascular levels, oxidative stress is highly implicated in myocardial infarction, ischemia/reperfusion, or heart failure. Here, we will first detail the physiological role of low ROS production in the heart and the vessels. Indeed, ROS are able to regulate multiple cardiovascular functions, such as cell proliferation, migration, and death. Second, we will investigate the implication of oxidative stress in cardiovascular diseases. Then, we will focus on ROS produced by NAPDH oxidase or during endothelial or mitochondrial dysfunction. Given the importance of oxidative stress at the cardiovascular level, antioxidant therapies could be a real benefit. In the last part of this review, we will detail the new therapeutic strategies potentially involved in cardiovascular protection and currently under study.

Vitamin D Protects against Oxidative Stress and Inflammation in Human Retinal Cells

Diabetic retinopathy is a vision-threatening microvascular complication of diabetes and is one of the leading causes of blindness. Oxidative stress and inflammation play a major role in its pathogenesis, and new therapies counteracting these contributors could be of great interest. In the current study, we investigated the role of vitamin D against oxidative stress and inflammation in human retinal pigment epithelium (RPE) and human retinal endothelial cell lines. We demonstrate that vitamin D effectively counteracts the oxidative stress induced by hydrogen peroxide (H₂O₂). In addition, the increased levels of proinflammatory proteins such as Interleukin (IL)-6, IL-8, Monocyte chemoattractant protein (MCP)-1, Interferon (IFN)-γ, and tumor necrosis factor (TNF)-α triggered by lipopolysaccharide (LPS) exposure were significantly decreased by vitamin D addition. Interestingly, the increased IL-18 only decreased by vitamin D addition in endothelial cells but not in RPE cells, suggesting a main antiangiogenic role under inflammatory conditions. Moreover, H₂O₂ and LPS induced the alteration and morphological damage of tight junctions in adult retinal pigment epithelium (ARPE-19) cells that were restored under oxidative and inflammatory conditions by the addition of vitamin D to the media. In conclusion, our data suggest that vitamin D could protect the retina by enhancing antioxidant defense and through exhibiting anti-inflammatory properties.

Vitamin D can be effective on the prevention of COVID-19 complications: A narrative review on molecular aspects

The widespread COVID-19 pandemic has been, currently, converted to a catastrophic human health challenge. Vitamin D (VD) and its metabolites have been used as a palliative treatment for chronic inflammatory and infectious diseases from ancient times. In the current study, some molecular aspects of the potential effects of VD against COVID-19 side-effects have been discussed. An arguable role in autophagy or apoptosis control has been suggested for VD through calcium signaling at the mitochondrial and ER levels. 1,25(OH)2D3 is also an immunomodulator that affects the development of B-cells, T-cells, and NK cells in both innate and acquired immunity. The production of some anti-microbial molecules such as defensins and cathelicidins is also stimulated by VD. The overexpression of glutathione, glutathione peroxidase, and superoxide dismutase, and down-regulation of NADPH oxidase are induced by VD to reduce the oxidative stress. Moreover, the multi-organ failure due to a cytokine storm induced by SARS-CoV2 in COVID-19 may be prevented by the immunomodulatory effects of VD. It can also downregulate the renin-angiotensin system which has a protective role against cardiovascular complications induced by COVID-19. Given the many experimental and molecular evidences due to the potential protective effects of VD on the prevention of the COVID-19-induced morbidities, a VD supplementation is suggested to prevent the lethal side-effects of the infection. It is particularly recommended in VD-deficient patients or those at greater risk of serious or critical effects of COVID-19, including the elderly, and patients with pre-existing chronic diseases, especially those in nursing homes, care facilities, and hospitals.

Early myocardial injury biomarkers in diabetic hyperlipidemic rats: Impact of 10-dehydrogingerdione and vitamin D3

IMPACT STATEMENT

Hyperlipidemia represents a major risk factor for cardiovascular diseases leading to myocardial injury (MI). The present study aimed to illustrate the pattern of myocardial injury induced in diabetic hyperlipidemic rat model and the effect of vitamin D3, 10-dehydrogingerdione (10-DHGD) intake either individually or in combination form.

Cardioprotective Effect of Paricalcitol on Amitriptyline-Induced Cardiotoxicity in Rats: Comparison of [99mTc]PYP Cardiac Scintigraphy with Electrocardiographic and Biochemical Findings

Taking an overdose of AMT, a commonly prescribed tricyclic antidepressant drug, has an increased risk of sudden cardiac death. The cardiotoxicity of amitriptyline (AMT) is a commonly observed toxicity with high morbidity and mortality rates in emergency departments (ED). Nevertheless, there are still no effective treatment options for AMT-induced cardiotoxicity. The aim of the present study was to evaluate the effects of paricalcitol (PRC), a Vitamin D receptor agonist, using electrocardiographic (ECG), biochemical, and scintigraphic methods. Twenty-eight male Wistar rats were randomly divided into four groups: untreated control (CON), amitriptyline-induced cardiotoxicity (AMT), paricalcitol (PRC), and amitriptyline + paricalcitol (AMT + PRC). Cardiotoxicity was induced by intraperitoneal (i.p) injection of a single-dose AMT (100 mg/kg). PRC was administered as 10 μg/kg (i.p.) after the injection of AMT. We examined ECG, biochemical, and scintigraphic results of PRC administration on AMT-induced changes. Cardiotoxicity of AMT was characterized by conduction abnormalities (increased QRS complex, T wave, and QT interval duration and elevation of ST segment amplitude), elevated ^99mTechnetium Pyrophosphate ([^99mTc]PYP) uptake, and increased cardiac troponin T (cTnT) levels. Treatment with PRC significantly decreased all AMT-associated conduction abnormalities in ECG (p < 0.001), and decreased [^99mTc]PYP uptake (p < 0.001) and serum cTnT level (p < 0.001). The present study indicated that the vitamin D receptor agonist paricalcitol could decrease the AMT-induced cardiotoxicity. This suggests [^99mTc]PYP as a non-invasive method for the evaluation of myocardial injury induced by AMT. According to the results of the present study, PRC has beneficial effects on AMT-induced cardiotoxicity.

Ghrelin protects against obesity-induced myocardial injury by regulating the lncRNA H19/miR-29a/IGF-1 signalling axis

BACKGROUND

Obesity is associated with the impairment of cardiac fitness and consequent ventricular dysfunction and heart failure. Ghrelin has been largely documented to be cardioprotective against ischaemia/reperfusion injury. However, the role of ghrelin in obesity-induced myocardial injury is largely unknown. This study sought to determine the cardiac effect of ghrelin against obesity-induced injury and the underlying mechanisms.

METHODS

The effect of ghrelin was evaluated in a mouse model of obesity and a palmitic acid (PA)-treated cardiomyocyte cell line with or without ghrelin transfection. Gene and protein expression levels were determined by real-time PCR and western blot, respectively. Cell apoptosis was measured by flow cytometry analysis.

RESULTS

In the present study, we found that both a high-fat diet (HFD) and PA treatment caused myocardial injury by increasing apoptosis and the expression of inflammatory cytokines. Overexpression of ghrelin reversed the effects induced by HFD or PA treatment. Knockdown of lncRNA H19 or overexpression of miR-29a abrogated the cardioprotective effects of ghrelin against apoptosis and inflammation. We also found that IGF-1 was a target gene of miR-29a and that H19 regulated IGF-1 expression via miR-29a. Overexpression of IGF-1 partially reversed the apoptosis and inflammation promoting effects of miR-29a.

CONCLUSIONS

Our findings suggested that ghrelin protected against obesity-induced myocardial injury by regulating the H19/miR-29a/IGF-1 signalling axis, providing further evidence for the clinical application of ghrelin.

Association between calcitriol and paricalcitol with oxidative stress in patients with hemodialysis

Background: The pathophysiological basis of chronic kidney disease and its complications, including cardiovascular disease, are associated with chronic inflammation and oxidative stress. We investigated the effects of active vitamin D (calcitriol) and synthetic vitamin D analog (paricalcitol) on oxidative stress in hemodialysis patients. Methods: This cross-sectional study was composed of 83 patients with a minimum hemodialysis vintage of one year. Patients with a history of any infection, malignancy, and chronic inflammatory disease were excluded. Oxidative markers (total oxidant and antioxidant status) and inflammation markers (C-reactive protein and interleukin-6) were analyzed. Results: A total of 47% (39/83) patients were using active or analog vitamin D. Total antioxidant status was significantly higher in patients with using active or analog vitamin D than those who did not use (p = 0.006). Whereas, total oxidant status and oxidative stress index were significantly higher in patients with not using vitamin D when compared with the patients who were using vitamin D preparation (p = 0.005 and p = 0.004, respectively). On the other hand, total antioxidant status, total oxidant status, and oxidative stress index were similar between patients who used active vitamin D or vitamin D analog (p = 0.6; p = 0.4 and p = 0.7, respectively). Conclusion: The use of active or selective vitamin D analog in these patients decreases total oxidant status and increases total antioxidant status. Also, paricalcitol is as effective as calcitriol in decreasing total oxidant status and increasing total antioxidant status in patients with chronic kidney disease.

Protection of cholinergic and antioxidant system contributes to the effect of Vitamin D3 ameliorating memory dysfunction in sporadic dementia of Alzheimer's type

OBJECTIVE

Investigate Vitamin D3 (VD3) effect on the Acetylcholinesterase (AChE), oxidative damage and behavioral tests in animals subjected to Intracerebroventicular injection of Streptozotocin (ICV-STZ) simulating a Sporadic Dementia of Alzheimer's Type (SDAT) and treated with VD3 (21 days).

METHODS

Animals were divided into eight groups: Vehicle, VD12.5 μg/kg, VD42 μg/kg, VD125 μg/kg, STZ, STZ+VD12.5 μg/kg, STZ+VD42 μg/kg, STZ+VD125 μg/kg.

RESULTS

VD3 prevented the increase in AChE in groups of VD42 µg/kg and VD125 µg/kg; in AChE of synaptossomes and TBARS levels prevented the increase in group VD125 µg/kg; in ROS levels there was not a significant difference; for the Carbonyl Content all doses prevented the increase. Total Thiols prevent the decrease in VD42 µg/kg and VD125 µg/kg, and Reduced Glutathione prevented the decrease in VD125 µg/kg, Oxidized Glutathione prevented the increase in VD125 µg/kg. In relation to behavioral tests, the VD3 prevented the increase in time to find (days 2 and 3), in the time to find the platform (day 3) and in time spent in the quadrant (day 2). However, in relation to crossings there was not difference in groups. These results indicated the therapeutic effect of the VD3 in model of STZ in rats.

The Impact of Obesity on the Association between Vitamin D Deficiency and Cardiovascular Disease

The aim of this article is to review the literature regarding the relationship between vitamin D deficiency and cardiovascular disease (CVD) and its modification in the presence of obesity. Despite the strong association between vitamin D status and cardiovascular outcomes, vitamin D supplementation trials in the general population have failed to decrease the incidence of cardiovascular events and mortality. A comprehensive study of the published literature and a comparison with experimental data lead to the conclusion that obesity, due to its high prevalence and strong association with both vitamin D deficiency and CVD, may act as a critical confounder, which is responsible for the different results on this association. Adoption of a vitamin D preventive supplementation strategy for CVD is unlikely to yield any benefit to the general population. However, it might be particularly useful in obese adults with increased risk for CVD.

Serum and Dietary Folate and Vitamin B12 Levels Account for Differences in Cellular Aging: Evidence Based on Telomere Findings in 5581 U.S. Adults

Folate and vitamin B₁₂ are essential for a variety of metabolic processes. Both micronutrients have been shown to reduce oxidative stress significantly. The present cross-sectional investigation evaluated the association between serum and dietary folate and vitamin B₁₂ levels and leukocyte telomere length, an index of cellular aging influenced by oxidative stress. The study included 5581 adults from the National Health and Nutrition Examination Survey (NHANES). Because participants were randomly selected, results are generalizable to all civilian, noninstitutionalized U.S. adults. A blood draw provided DNA and serum folate and B₁₂ information. The quantitative polymerase chain reaction method was used to measure telomere length. The Bio-Rad Quantaphase II folate and vitamin B₁₂ radioassay kit was used to quantify levels of folate and vitamin B₁₂. Dietary folate and vitamin B₁₂ were assessed using a multipass 24 h recall. In some models, age, race, smoking pack-years, alcohol use, body mass index, total physical activity, hours fasted before the blood draw, and diabetes status were employed as covariates to minimize their influence. Findings showed that for each additional year of chronological age, telomeres were 15.6 base pairs shorter, on average (F = 378.8, p < 0.0001). Men had shorter telomeres than women after adjusting for all the covariates (F = 6.8, p = 0.0146). Serum (F = 10.5, p = 0.0030) and dietary (F = 5.0, p = 0.0325) folate concentrations were each linearly related to telomere length in women, but not in men, after controlling for age and race. Serum vitamin B₁₂ and telomere length had a nonsignificant, inverse relationship in women, with age and race controlled (F = 2.8, p = 0.1056), but no relation in men. Dietary vitamin B₁₂ was linearly related to telomere length in women, after adjusting for age and race (F = 4.3, p = 0.0468), but not in men. Overall, evidence indicates that folate and vitamin B₁₂ levels, especially folate, account for meaningful differences in cell aging in women, but not in men.

Resveratrol and 1,25-dihydroxyvitamin D co-administration protects the heart against D-galactose-induced aging in rats: evaluation of serum and cardiac levels of klotho

The current study investigates the cooperative cardioprotective effect of calcitriol (active form of vitamin D) combined with resveratrol in a rat model of D-galactose (D.gal)-induced aging. Male Wistar rats received resveratrol (D.gal + Res), calcitriol (D.gal + Cal), or a combination of them (D.gal + Res + Cal). Intact animals served as control (Ctl). Blood pressure (BP) was recorded by cannulation of the left carotid artery. Fibrosis and cell size were assessed by Masson's trichrome and hematoxylin-eosin staining, respectively. Cardiac and serum level of antiaging protein, klotho, was measured by ELISA assay method. Gene expression was evaluated by real-time RT-PCR. Biochemical tests were performed according to the standardized method. In D.gal + Res + Cal group, BP, heart weight-to-body weight ratio, and cardiomyocytes size decreased significantly compared with D-gal group. The cardiac transcription levels of catalase and superoxide dismutase 1 and 2 were upregulated in D.gal + Res + Cal compared to the D.gal group (P < 0.001, P < 0.05, P < 0.05, respectively). Increased level of malondialdehyde was observed in D.gal group (P < 0.01 vs. Ctl) which was normalized partially in D.gal + Res + Cal group (P < 0.05). Catalase and superoxide dismutase activity also increased in D.gal + Res + Cal group (P < 0.01 vs. D.gal). Cardiac Klotho, as the antiaging protein, remained unchanged at mRNA and protein levels among the experimental groups. The serum level of Klotho did not change significantly in D.gal group; however, in D.gal + Res + Cal group, serum klotho concentration was increased (P < 0.05 vs. D.gal). It could be concluded that co-administration of resveratrol and vitamin D protects the heart against aging-induced damage by the modulation of hemodynamic parameters and antioxidant status of the heart. Furthermore, increased serum level of klotho could be a novel mechanism for antiaging effects of resveratrol and vitamin D.

Resistance Exercise Modulates Oxidative Stress Parameters and TNF-α Content in the Heart of Mice with Diet-Induced Obesity

Background

Obesity can be characterized by low-grade chronic inflammation and is associated with an excesso production of reactive oxygen species, factors that contribute to coronary heart disease and other cardiomyopathies.

Objective

To verify the effects of resistance exercise training on oxidative stress and inflammatory parameters on mice with obesity induced by a high-fat diet (HFD).

Methods

24 Swiss mice were divided into 4 groups: standard diet (SD), SD + resistance exercise (SD + RE), diet-induced obesity (DIO), DIO + RE. The animals were fed SD or HFD for 26 weeks and performed resistance exercises in the last 8 weeks of the study. The insulin tolerance test (ITT) and body weight monitoring were performed to assess the clinical parameters. Oxidative stress and inflammation parameters were evaluated in the cardiac tissue. Data were expressed by mean and standard deviation (p < 0.05).

Results

The DIO group had a significant increase in reactive oxygen species levels and lipid peroxidation with reduction after exercise. Superoxide dismutase and the glutathione system showed no significant changes in DIO animals, with an increase in SD + RE. Only catalase activity decreased with both diet and exercise influence. There was an increase in tumor necrosis factor-alpha (TNF-α) in the DIO group, characterizing a possible inflammatory condition, with a decrease when exposed to resistance training (DIO+RE).

Conclusion

The DIO resulted in a redox imbalance in cardiac tissue, but the RE was able to modulate these parameters, as well as to control the increase in TNF-α levels.

The effect of chronic oral vitamin D supplementation on adiposity and insulin secretion in hypothalamic obese rats

Reduced plasma vitamin D (VD) levels may contribute to excessive white adipose tissue, insulin resistance (IR) and dyslipidaemia. We evaluated the effect of chronic oral VD supplementation on adiposity and insulin secretion in monosodium glutamate (MSG)-treated rats. During their first 5 d of life, male neonate rats received subcutaneous injections of MSG (4 g/kg), while the control (CON) group received saline solution. After weaning, groups were randomly distributed into VD supplemented (12 µg/kg; three times/week) and non-supplemented (NS) rats, forming four experimental groups (n 15 rats/group): CON-NS, CON-VD, MSG-NS and MSG-VD. At 76 d of life, rats were submitted to an oral glucose tolerance test (OGTT; 2 g/kg), and at 86 d, obesity, IR and plasma metabolic parameters were evaluated. Pancreatic islets were isolated for glucose-induced insulin secretion (GIIS), cholinergic insulinotropic response and muscarinic 3 receptor (M3R), protein kinase C (PKC) and protein kinase A (PKA) expressions. Pancreas was submitted to histological analyses. VD supplementation decreased hyperinsulinaemia (86 %), hypertriacylglycerolaemia (50 %) and restored insulin sensibility (89 %) in MSG-VD rats, without modifying adiposity, OGTT or GIIS, compared with the MSG-NS group. The cholinergic action was reduced (57 %) in islets from MSG-VD rats, without any change in M3R, PKA or PKC expression. In conclusion, chronic oral VD supplementation of MSG-obese rats was able to prevent hyperinsulinaemia and IR, improving triacylglycerolaemia without modifying adiposity. A reduced cholinergic pancreatic effect, in response to VD, could be involved in the normalisation of plasma insulin levels, an event that appears to be independent of M3R and its downstream pathways.

Vitamin D3 supplementation ameliorates ovariectomy-induced cardiac apoptotic and structural changes in adult albino rats

The effect of vitamin D on cardiac dysfunction after menopause is still under investigation. Therefore, we investigated the effect of vitamin D3 on cardiac apoptotic and structural changes in ovariectomized rats. Forty adult female albino rats were divided into 4 equal groups: sham rats, sham rats treated with vitamin D3, ovariectomized rats, and ovariectomized rats treated with vitamin D3 (500 IU/kg per day for 6 weeks, orally). Body mass, blood pressure, heart rate, and whole heart mass (WHM) were measured. Serum soluble receptors of advanced glycation end products (sRAGE), C-reactive protein, malondialdehyde, and total antioxidant capacity were estimated. Cardiac sections were stained with haematoxylin-eosin and Masson's trichrome stain. Fas and FasL apoptosis-related proteins were detected by immunohistochemistry. Vitamin D3 treatment significantly decreased ovariectomy-induced cardiac Fas and FasL apoptosis-related proteins, whole heart mass, body mass, C-reactive protein, and malondialdehyde accompanied by decreased inflammation and reduced collagen deposition between cardiac muscle fibres. However, vitamin D3 significantly increased total antioxidant capacity and sRAGE in ovariectomized and sham treated groups. Our findings suggest that vitamin D3 treatment can prevent ovariectomy-induced cardiac structural and apoptotic changes in rats via increasing sRAGE and antioxidant activity. Our results suggest that vitamin D3 has therapeutic effect against postmenopausal cardiovascular disease.

Dietary total antioxidant capacity (TAC) among candidates for coronary artery bypass grafting (CABG) surgery: Emphasis to possible beneficial role of TAC on serum vitamin D

Aims

Recently, the clinical importance of total antioxidant capacity (TAC) and its protective role against several chronic diseases like cardiovascular disease, osteoporosis and several types of cancers has been reported. However, its association with cardio-metabolic risk factors among patients candidate for coronary artery bypass graft surgery (CABG) has not been evaluated yet. CABG is associated with increased oxidative stress and free radicals; so, the current study was aimed to evaluate the potential association of TAC with cardiovascular risk factors among patients candidate for CABG.

Methods and materials

In the current cross-sectional study, 454 patients aged 35–80 years as candidates of CABG and hospitalized in Tehran Heart Center were enrolled. Anthropometric and demographic characteristics were obtained from all participants. Total dietary antioxidant capacity (TAC) was calculated according to the findings of semi-quantitative food-frequency questionnaire (FFQ). Biochemical parameters including serum lipids, albumin, creatinine, HbA1C, C-reactive protein (CRP), lipoprotein (a), creatinine, blood urea nitrogen (BUN) and serum vitamin D concentrations were also assessed by commercial laboratory methods.

Results

Male patients in the top quintiles of TAC had significantly lower prevalence of hypertension (35.1% vs 45.9%). Moreover, male patients at fifth quintile of TAC were 2% more serum vitamin D concentrations, 3% lower serum cholesterol concentrations compared with lowest quintile. Top quintiles of TAC make patients more likely to have low hematocrit and high serum albumin concentrations compared with lowest quintiles (P < 0.05). However, in female participants, only serum creatinine concentration was in negative association with TAC. In comparison of clinical parameters, females in the fifth quintile of TAC had 9% higher EF compared with patients in the first quintile (P = 0.021).

Conclusion

To our findings, higher dietary antioxidant capacity was associated with lower prevalence of hypertension, lower hematocrit, total cholesterol and higher albumin and vitamin D concentrations. Therefore, high dietary TAC could be considered as a potent protective tool against cardio-metabolic risk factors in patients CABG candidate for especially in male patients.

Vitamin D protects human melanocytes against oxidative damage by activation of Wnt/β-catenin signaling

Vitamin D analogs have been widely utilized for the treatment of vitiligo, but the molecular mechanism underlying their pharmacological effects (especially their antioxidant properties) has not yet been investigated. We evaluated the relationship between serum vitamin D level and oxidative damage severity in vitiligo patients, and investigated the molecular mechanism of vitamin D in protecting melanocytes against oxidative stress. Serum levels of 25-hydroxyvitamin D and malondialdehyde (MDA) were first measured in patients. A variety of in vitro experiments such as intracellular reactive oxygen species (ROS), cellular viability, migration, and apoptotic assays were then performed to detect the effects of vitamin D or β-catenin silencing on H₂O₂-treated melanocytes. Expression of Wnt/β-catenin, Nrf2, apoptotic, and MITF pathways was finally examined using quantitative real-time PCR and western blot. In this study, we initially found that vitamin D insufficiency was closely associated with the severity of oxidative stress in vitiligo patients. Using ex vivo cell models, we further showed that vitamin D positively modulated β-catenin signaling at both translational and posttranslational levels in melanocytes under oxidative stress. Like WNT agonists, vitamin D significantly inhibited ROS accumulation and cell apoptosis in H₂O₂-treated melanocytes and promoted their proliferative and migratory activity, while the protective effects of vitamin D against oxidative stress were abolished by β-catenin silencing in melanocytes. Furthermore, β-catenin deficiency also blocked the activation of Nrf2 and MITF as well as the inhibition of apoptosis induced by vitamin D. Taken together, vitamin D insufficiency was associated with severity of oxidative stress in vitiligo patients. Our work also provides new insights into the mechanism of vitamin D against vitiligo, in which vitamin D protects melanocytes against oxidative stress by activating Wnt/β-catenin signaling.

Neuroprotective effects of vitamin D on high fat diet- and palmitic acid-induced enteric neuronal loss in mice

Background

The role of vitamin D in obesity and diabetes is debated. Obese and/or diabetic patients have elevated levels of free fatty acids, increased susceptibility to gastrointestinal symptoms and are suggested to have altered vitamin D balance. The enteric nervous system is pivotal in regulating gastrointestinal activity and high fat diet (HFD) has been shown to cause loss of enteric neurons in ileum and colon. This study investigates the effect of vitamin D on HFD- and palmitic acid-induced enteric neuronal loss in vivo and in vitro.

Methods

Mice were fed either a normal diet (ND) or HFD supplemented with varying levels of vitamin D (from 0x to 20x normal vitamin D level) for 19 weeks. Ileum and colon were analyzed for neuronal numbers and remodeling. Primary cultures of myenteric neurons from mouse small intestine were treated with palmitic acid (4x10^-4M) and/or 1α,25-hydroxy-vitamin D3 (VD, 10^-11- 10^-7M) with or without modulators of lipid metabolism and VD pathways. Cultures were analyzed by immunocyto- and histochemical methods.

Results

Vitamin D supplementation had no effect on enteric neuronal survival in the ND group. HFD caused substantial loss of myenteric neurons in ileum and colon. Vitamin D supplementation between 0-2x normal had no effect on HFD-induced neuronal loss. Supplementation with 20x normal, prevented the HFD-induced neuronal loss. In vitro supplementation of VD prevented the palmitic acid-induced neuronal loss. The VD receptor (VDR) was not identified in enteric neurons. Enteric glia expressed the alternative VD receptor, protein disulphide isomerase family A member 3 (PDIA3), but PDIA3 was not found to mediate the VD response in vitro. Inhibition of peroxisome proliferator-activated receptor gamma (PPARγ) and immune neutralization of isocitrate lyase prevented the VD mediated neuroprotection to palmitic acid exposure.

Conclusions

Results show that VD protect enteric neurons against HFD and palmitic acid induced neuronal loss. The mechanism behind is suggested to be through activation of PPARγ leading to improved neuronal peroxisome function and metabolism of neuronal lipid intermediates.

Vitamin D attenuates gentamicin-induced acute renal damage via prevention of oxidative stress and DNA damage

Background:

Despite being one of the most nephrotoxic drugs, gentamicin (GM) remains a mainstay as a first-choice agent in a vast variety of clinical situations owing to its superlative efficiency as a broad-spectrum antibiotic in treating several life-threatening bacterial infections. This urgently calls for the need for in-depth analysis of the mechanisms governing GM-induced nephrotoxicity and entails the necessity of presenting novel protective agents capable of ameliorating those renal deleterious effects. The reactive oxygen species and redox-sensitive transcription factors in GM-induced nephrotoxicity have recently called attention.

Purpose:

This study has been designed to shed light on the possible mechanisms of GM-induced nephrotoxicity and to provide a consensus set of histopathological, immunohistochemical, genetic and biochemical parameters elucidating the protective role of vitamin D against this nephrotoxicity.

Methods:

Twenty-four adult male albino rats were equally divided into four groups: group I (control group), group II (GM), group III (GM + vitamin D) and group IV (vitamin D only). Kidney function tests, histopathological examination, gene expression of nuclear factor 2, nuclear factor kappa beta (NF-κB) and western blot of NF-κB p65, assessment of glutathione peroxidase and nicotinamide adenine dinucleotide phosphate oxidase (NADPH) oxidase by ELISA, as well as immunohistochemical evaluation of inducible nitric oxide, malondialdehyde, 8-hydroxy 2 deoxyguanine and vitamin D receptor, have been carried out.

Results:

The kidney function deterioration, tissue oxidative stress development and the histopathological changes induced by GM were significantly attenuated by vitamin D administration.

Conclusion:

Vitamin D attenuates GM nephrotoxicity through its antioxidant properties and prevention of DNA damage.

The association between serum vitamin D levels and renal tubular dysfunction in a general population exposed to cadmium in China

Cadmium exposure can cause renal tubular dysfunction. Recent studies show that vitamin D can play multiple roles in the body. However, the association between serum vitamin D levels and renal tubular dysfunction in a general population exposed to cadmium has not been clarified. We performed study to assess the effects of cadmium on serum 25(OH) D levels and the association between serum 25(OH) D levels and renal tubular dysfunction in a population environmentally exposed to cadmium. A total of 133 subjects living in control area and two cadmium polluted areas were included in the present study. Cadmium in urine (UCd) and blood (BCd), urinary β2Microglobulin (UBMG), urinary retinol binding protein (URBP) and serum 25 (OH) D were determined. Logistic regression was used to estimate the association between 25 (OH) D and prevalence of renal tubular dysfunction. No significant differences were observed in serum 25(OH) D levels among the four quartile of UCd and BCd after adjusting with cofounders. After adjusted with the confounders, the odds ratio (OR) of subjects with 25(OH) D ≥ 40 ng/ml were 0.20 (95%CI: 0.1–0.8) if UBMG was chosen as indicators of renal dysfunction and 0.28 (95%CI: 0.1–1.1) if URBP was chosen as indicators of renal dysfunction, compared with those with 25(OH) D < 30 ng/ml, respectively. Similar results were observed in those subjects living in cadmium polluted areas or with high level of UCd or BCd. Our data indicated that cadmium exposure did not affect serum 25(OH) D level and high 25 (OH) D levels were associated with a decreased risk of renal tubular dysfunction induced by cadmium.

Vitamin D alleviates lead induced renal and testicular injuries by immunomodulatory and antioxidant mechanisms in rats

This study measured the effects of vitamin D (VD) supplementation on the underlying molecular pathways involved in renal and testicular damage induced by lead (Pb) toxicity. Thirty two adult male Wistar rats were divided equally into four groups that were treated individually or simultaneously, except the negative control, for four weeks with lead acetate in drinking water (1,000 mg/L) and/or intramuscular VD (1,000 IU/kg; 3 days/week). Pb toxicity markedly reduced serum VD and Ca²⁺, induced substantial renal and testicular injuries with concomitant significant alterations in the expression of VD metabolising enzymes, its receptor and binding protein, and the calcium sensing receptor. Pb also significantly promoted lipid peroxidation and pro-inflammatory cytokines (IL-4 and TNF-α) in the organs of interest concomitantly with declines in several anti-oxidative markers (glutathione, glutathione peroxidase and catalase) and the anti-inflammatory cytokine, IL-10. The co-administration of VD with Pb markedly mitigated renal and testicular injuries compared with positive controls. This was associated with restoration of the expression of VD related molecules, promotion of anti-oxidative and anti-inflammatory markers, but tissue Pb concentrations were unaffected. In conclusion, this report is the first to reveal potential protective effects for VD against Pb-induced renal and testicular injuries via anti-inflammatory and anti-oxidative mechanisms.