Anna Jabłecka

Green tea extract reduces blood pressure, inflammatory biomarkers, and oxidative stress and improves parameters associated with insulin resistance in obese, hypertensive patients.

Green tea (GT) consumption is known to be associated with enhanced cardiovascular and metabolic health. The purpose of this study is to examine the hypothesis that supplementation with GT alters insulin resistance and associated cardiovascular risk factors in obese, hypertensive patients. In a double-blind, placebo-controlled trial, 56 obese, hypertensive subjects were randomized to receive a daily supplement of 1 capsule that contained either 379 mg of GT extract (GTE) or a matching placebo, for 3 months. At baseline and after 3 months of treatment, the anthropometric parameters, blood pressure, plasma lipid levels, glucose levels, creatinine levels, tumor necrosis factor α levels, C-reactive protein levels, total antioxidant status, and insulin levels were assessed. Insulin resistance was evaluated according to the homeostasis model assessment-insulin resistance protocol. After 3 months of supplementation, both systolic and diastolic blood pressures had significantly decreased in the GTE group as compared with the placebo group (P < .01). Considerable (P < .01) reductions in fasting serum glucose and insulin levels and insulin resistance were observed in the GTE group when compared with the placebo group. Serum tumor necrosis factor α and C-reactive protein were significantly lower, whereas total antioxidant status increased in the GTE group compared with the placebo (P < .05). Supplementation also contributed to significant (P < .05) decreases in the total and low-density lipoprotein cholesterol and triglycerides, but an increase in high-density lipoprotein cholesterol. In conclusion, daily supplementation with 379 mg of GTE favorably influences blood pressure, insulin resistance, inflammation and oxidative stress, and lipid profile in patients with obesity-related hypertension.

Plasma total homocysteine is a determinant of carotid intima-media thickness and circulating endothelial progenitor cells in patients with newly diagnosed hypertension

Abstract Background: Accumulating evidence suggests that elevated plasma homocysteine (Hcy), prevalent in hypertensive patients, affects oxidant/antioxidant balance of the body, and is linked to the development of atherosclerosis, inflammation, and endothelium injury. Our objective was to examine a hypothesis that Hcy is a predictor of total antioxidant status (TAS) and endothelial progenitor cells (EPCs), important in the repair of injured endothelium, in hypertensive patients. Methods: This study was conducted with newly diagnosed essential hypertension patients (n=42) and healthy controls (n=20). Anthropometric and biochemical characteristics, including plasma Hcy, lipids, TAS, and C-reactive protein (CRP) were quantified. Intima-media thickness (IMT) was assessed in carotid arteries. Blood derived EPCs were quantified using an in vitro culture assay. Results: Hcy, IMT, and CRP were significantly elevated while TAS and EPCs were significantly lower in hypertensive patients compared with controls. In multivariate regression analysis Hcy was a predictor of IMT of carotid artery and EPCs number. Conclusions: Our results suggest that Hcy might increase carotid artery IMT by reducing EPCs numbers. Possible involvement of Hcy in the reduction of EPCs number in hypertensive patients might be in part mediated by Hcy influence on the TAS.

Supplementation with L-arginine favorably influences plasminogen activator inhibitor type 1 concentration in obese patients. A randomized, double blind trial.

Background: Elevated plasminogen activator inhibitor type 1 (PAI 1) plays an important role in the pathogenesis of excess blood coagulability in obese patients. L-arginine supplementation has shown to be associated with enhanced cardiovascular and metabolic health. The aim of the study was to assess the effect of L-arginine supplementation on PAI 1 concentration and to evaluate the relation to changes in nitric oxide (NO) plasma level, insulin sensitivity (M value), and total antioxidant status (TAS) in obese patients. Material/subjects and methods: A randomized, double-blind, placebo-controlled study was conducted from March 2010 to June 2011. Eighty-eight obese patients were randomly assigned to receive either 9 g of L-arginine or placebo daily for 6 months. At baseline and after 6 months, selected anthropometrical measurements and blood biochemical analyses were performed, and PAI 1, NO, TAS levels were assessed. Insulin sensitivity was evaluated using the hyperinsulinemic euglycemic clamp technique. Results: We found that 6-month L-arginine supplementation resulted in significant decrease of PAI 1. Significant increase of NO, TAS, and insulin sensitivity level were noticed. In a group of patients treated with L-arginine, negative correlation between a change of insulin sensitivity value and a change of PAI 1 concentration was found. Conclusions: The present findings demonstrate favorable influence of L-arginine supplementation on PAI 1 concentration in obese patients. Beneficial influence is related to insulin sensitivity improvement. The potential therapeutic role of L-arginine administration in patients with obesity needs further investigation.

Influence of hypertension, obesity and nicotine abuse on quantitative and qualitative changes in acute-phase proteins in patients with essential hypertension

Summary Background Hypertension is a powerful risk factor for cardiovascular disease and frequently occurs in conjunction with obesity. Accumulative evidence suggests a link between inflammation and hypertension. The aim of study was to evaluate whether blood pressure, obesity and smoking may influence acute-phase response. Material/Methods Ninety-two patients with essential hypertension and 75 healthy volunteers as a control group were studied. In all subjects assessment of hsCRP, α1-acid glycoprotein (AGP), α1-antichymotrypsin, transferrin, α1-antitrypsin, and C3 and C4 complement were performed. Evaluation of glycosylation profile and reactivity coefficient (RC) for AGP was done by means of affinity immunoelectrophoresis with concanavalin A as a ligand. Results When compared to the controls, hypertensive subjects presented significantly higher hsCRP concentrations and lower transferrin level. Hypertensive patients had elevated AGP-AC. The intensification of the inflammatory reaction was greater in the subgroup of hypertensive patients smoking cigarettes. In obese hypertensives, elevated serum C3 complement level was found. Conclusions We conclude that arterial hypertension may evoke the acute-phase response in humans. Markers of acute-phase response are particularly strongly expressed in smokers. Serum C 3 complement, but not other APPs, is elevated in hypertension coexisting with obesity.

Coenzyme Q10 - A new player in the treatment of heart failure?

Coenzyme Q10 is the only endogenously synthesized lipid with a redox function which exhibits broad tissue and intracellular distribution in mammals. Beneficial effects of Coenzyme Q10 supplementation were observed in several age-related diseases including heart failure. CoQ10 (coenzyme Q10) level is significantly decreased in patients with this disease, which correlates with severity of clinical symptoms. Supplementation with various pharmaceutical formulations of CoQ10 improves impaired cardiac function and clinical course of heart failure. Current data from clinical trials indicate that CoQ10 can significantly reduce morbidity and mortality of heart failure patients in addition to guideline recommended pharmacotherapy.

Influence of short-term L-arginine supplementation on carbohydrate balance in rats with ischemia-reperfusion syndrome

BACKGROUND There are studies showing stimulative effect of arginine on insulin secretion. This mechanism is not fully explained. The effects of the impact of arginine on carbohydrate balance under the conditions of ischemia and reperfusion remain to be determined. The aim of this study is the evaluation of the influence of short-term L-arginine supplementation on the concentration of glucose and insulin in blood and insulin binding in rat skeletal muscle under the conditions of ischemia and reperfusion. METHODS The study was conducted on male Wistar rats with average body mass 250 ± 30 g. Animals were divided into four groups: Group I - control, Group II - placebo, Group III - L-arginine 500 mg/kg/24 h for 5 days, Group IV - L-arginine and L-NAME (75 μmol/rat/24 h) for 5 days. Each group was divided into subgroups depending on duration of ischemia and reperfusion. Acute ischemia of hind limb was induced in each group by putting pneumatic tourniquet on the thigh. Blood samples and skeletal muscles were collected from the rats. Plasma concentrations of glucose and insulin were measured. Insulin binding to insulin receptors was determined in skeletal muscle. RESULTS A clear reduction of insulin binding to receptor was found in the group of animals without ischemia and the group supplemented with L-arginine and subjected to 4-h ischemia and 30- and 120-min reperfusion. A significant increase in insulin level was found in groups of animals with L-arginine and/or L-NAME subjected to 4-h ischemia at all times of reperfusion. Supplementation with L-arginine and/or L-NAME decreased levels of glucose in blood serum of animals undergoing ischemia-reperfusion syndrome compared to the control and placebo groups. CONCLUSION Under conditions of ischemia-reperfusion, short-term administration of L-arginine causes a decrease in insulin binding capacity of insulin receptors in skeletal muscle, an increase in insulin level and a decrease in the concentration of glucose in blood serum.

Current approach for detection of sub-clinical left ventricular dysfunction associated with chemotherapy

The article describes the current knowledge concerning approaches for detection of sub-clinical left ventricular dysfunction associated with chemotherapy. The authors focused on the problem of defining cardiotoxicity as well as diagnostic methods, which may be useful in predicting the occurrence of such complications. Currently, cardiac biomarkers measurement (troponin, NT-proBNP), tissue Doppler-based strain imaging and peak systolic longitudinal strain rate are most useful for detection of early myocardial changes during therapy, whereas speckle tracking echocardiography (STE) and peak systolic global longitudinal strain (GLS) appear to be the best measure. The problem of cardiotoxicity requires close cooperation between oncologists and cardiologists, particularly in light of the growing number of cancer cases.

The effect of L-arginine and ascorbic acid on the visceral fat and the concentrations of metalloproteinases 2 and 9 in high-fat-diet rats

INTRODUCTION L-arginine (L-arg) and vitamin C supplementation may decrease fat accumulation and have a favourable effect on carbohydrate metabolism. This is partly caused by matrix metalloproteinases (MMPs), which are involved in adipocyte development and remodelling. Our study evaluated the effects of L-arg and vitamin C supplementation on the content of visceral fat (VF%), activity of MMPs, and insulin resistance (IR) in rats fed a high-fat diet (HFD). MATERIAL AND METHODS The experiment was performed using 48 Wistar rats divided into four groups: Group 1 was fed a standard diet, Group 2 a HFD, Group 3 a HFD supplemented with L-arg (A), and Group 4 a HFD supplemented with L-arg and vitamin C (AC). The animals were euthanized after six weeks. The concentrations of serum glucose, insulin, MMP-2, and MMP-9, as well as IR by Homeostatic Model Assessment (HOMA) and VF% were measured. RESULTS Statistically significant increases in VF%, MMP-2, MMP-9, insulin, and HOMA-IR levels were observed in the HFD group when compared to the control group. A smaller increase in VF%, insulin, and HOMA-IR was seen in Group 3 (A) and 4 (AC). L-arg supplementation protected against increases in MMP-2 and MMP-9 in Group 3 (A) and 4 (AC). CONCLUSIONS L-arginine could protect from an increase in visceral fat through a change in the activity of MMPs and amelioration of insulin sensitivity in rats fed a HFD. The addition of vitamin C did not improve the effects of L-arginine supplementation.

The influence of short-term l-arginine supplementation on rats’ muscular and hepatic cells in ischemia–reperfusion syndrome

Due to the complex mechanisms of l-arginine activity, it is difficult to determine the clinical significance of supplementation with this amino acid. The objective of this study was to determine the influence of short-term supplementation with l-arginine in stress conditions, induced by ischemia–reperfusion syndrome, by assessing the damage to muscular and hepatic cells on the basis of creatine kinase (CK), alanine aminotransferase (ALAT) and aspartic aminotransferase (AspAT) activity in blood and the level of oxygen free radicals in analyzed tissues of rats. We observed that induced ischemia of hind limb caused an increase in CK, ALAT and AspAT activity and an increase in the level of free radicals in liver, but not in skeletal muscle. Supplementation with l-arginine led to a reduction in serum activity of CK and AspAT and reduction of the level of free radicals in analysed tissues. Simultaneous supplementation with l-arginine AND l-NAME resulted in a reversal of changes induced by l-arginine supplementation in the case of AspAT and free radicals in skeletal muscle. The results indicate that under conditions of ischemia–reperfusion, short-term administration of l-arginine has a protective effect on skeletal muscle manifesting itself by reduction of CK in the serum and reduction of free radicals level in THIS tissue.

Evaluation of antihypertensive effect of l-arginine supplementation in patients with mild hypertension assessed with ambulatory blood pressure monitoring

BACKGROUND Arterial hypertension is one of the most important cardiovascular risk factors, featuring the unsatisfactory efficacy of current therapies. The cardiovascular disease paradigm which assumes a crucial role of the endothelial phenotype in shaping the state of the circulatory system has become increasingly dominant and endothelial dysfunction should be treated as avidly as the diseases of other organs. The most valued current anti-hypertensive therapies exert a positive influence on the endothelium due to their pleiotropic effects, but the search for new effective strategies aimed at improving endothelial function is underway. L-arginine trials are part of this quest. The few L-arginine studies in hypertension have brought inconclusive results. The aim of this study was to evaluate the anti-hypertensive efficacy and safety profile of L- arginine during four weeks of oral supplementation to healthy subjects and patients diagnosed with primary mild hypertension. MATERIAL/METHODS The study was completed by 54 participants. Ambulatory blood pressure monitoring (ABPM) was used to allot patients to either a healthy control group (19 subjects) or the hypertensive treatment group (35 patients). Later the patients were randomized to either L-arginine (2 or 4 g three times daily or placebo. All participants underwent physical examination and had all basic lab tests and ABPM performed. RESULTS Blood pressure (both systolic and diastolic) by ABPM showed statistically significant lowering after 4 weeks of L-arginine supplementation only in the subgroup of patients treated with 12 g of L-arginine daily, with a stronger hypotensive effect observed during the day. CONCLUSIONS The present findings demonstrate a strong association between L-arginine supplementation and blood pressure reduction.