High density lipoprotein cholesterol level is a robust predictor of lipid peroxidation irrespective of gender, age, obesity, and inflammatory or metabolic biomarkers

Tolypocladium sinense Mycelium Polysaccharide Alleviates Obesity, Lipid Metabolism Disorder, and Inflammation Caused by High Fat Diet via Improving Intestinal Barrier and Modulating Gut Microbiota

SCOPE

Tolypocladium sinense is a fungus isolated from Cordyceps. Cordyceps has some medicinal value and is also a daily health care product. This study explores the preventive effects of T. sinense mycelium polysaccharide (TSMP) on high-fat diet-induced obesity and chronic inflammation in mice.

METHODS AND RESULTS

Here, the study establishes an obese mouse model induced by high-fat diet. In this study, the mice are administered TSMP daily basis to evaluate its effect on alleviating obesity. The results show that TSMP can significantly inhibit obesity and alleviate dyslipidemia by regulating the expression of lipid metabolism-related genes such as liver kinase B1 (LKB1), phosphorylated AMP-activated protein kinase (pAMPK), peroxisome proliferator activated receptor α (PPARα), fatty acid synthase (FAS), and hydroxymethylglutaryl-CoA reductase (HMGCR) in the liver. TSMP can increase the protein expression of zona occludens-1 (ZO-1), Occludin, and Claudin-1 in the colon, improve the intestinal barrier dysfunction, and reduce the level of serum LPS, thereby reducing the inflammatory response. 16S rDNA sequencing shows that TSMP alters the intestinal microbiota by increasing the relative abundance of Akkermansia, Lactobacillus, and Prevotellaceae_NK3B31_group, while decreasing the relative abundance of Faecalibaculum.

CONCLUSION

The findings show that TSMP can inhibit obesity and alleviates obesity-related lipid metabolism disorders, inflammatory responses, and oxidative stress by modulating the gut microbiota and improving intestinal barrier.

Lifestyle-based oxidative balance score and its association with cardiometabolic health of the community-dwelling elderly: A cross-sectional secondary analysis

Background

Cardiometabolic diseases, the main disease burden in older adults, are largely caused by oxidative stress resulting from lifestyle factors. This study investigated the relationship between lifestyle-based oxidative balance scores and cardiometabolic health among the community-dwelling elderly.

Methods

This work conducted a secondary analysis of previous cross-sectional research data and constructed a lifestyle-based oxidative balance score (LOBS) including 4 components (higher scores were considered more antioxidant). Linear regression models and logistic regression models were used to evaluate the associations with cardiometabolic biomarkers and the number of cardiometabolic risk factors. Besides, we investigated whether these associations differed by covariates.

Results

A total of 710 individuals (60.99% female, median age 70.0 years) were recruited. The inverse associations of LOBS with SBP and TG and the positive association with HDLC were statistically significant in both linear and logistic regression models. In contrast, an inverse association of LOBS with DBP was significant only in the linear regression model (all P < 0.05). The associations of LOBS with TG and HDLC were not affected by age, gender, or socioeconomic level. A significant inverse association was observed between LOBS and the number of cardiometabolic risk factors. Compared with the lowest LOBS, the ORs for more cardiometabolic risk factors in the second and third intervals were 0.577 (0.422, 0.788) and 0.460 (0.301, 0.703) (both P < 0.001).

Conclusion

In summary, this study shows that antioxidant-predominant lifestyle exposure yields a better cardiometabolic health status. We recommend that general practitioners should offer comprehensive healthy lifestyle management to community-dwelling elderly.

Abnormal Endometrial Receptivity and Oxidative Stress in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder in women of childbearing age. Individual heterogeneity is evident, and the prevalence rate ranges between 6 and 15% globally. The prevalence rate of PCOS in Chinese women of childbearing age is 5.6%. The main manifestations are infertility, sparse menstruation, irregular vaginal bleeding, long-term endometrial hyperplasia, and endometrial cancer. PCOS is often associated with hyperandrogenemia, insulin resistance, hyperinsulinemia, obesity, metabolic syndrome, and intestinal flora disorder. Although there have been many studies in the past, the underlying pathophysiological mechanism of the disease is still unclear. Studies have shown that PCOS diseases and related complications are closely related to local oxidative stress imbalance in the endometrium, leading to poor endometrial receptivity and effects on pregnancy. Previous reviews have mainly focused on the abnormal mechanism of ovarian oxidative stress in women with PCOS, while reviews on endometrial receptivity and oxidative stress are relatively insufficient. This study reviews the abnormal cellular and molecular mechanisms of oxidative stress due to comorbidities in women with PCOS, leading to a downregulation of endometrial receptivity.

Modulation of gut microbiota and markers of metabolic syndrome in mice on cholesterol and fat enriched diet by butterfly pea flower kombucha

Clitoria ternatea, with an alternative name, Butterfly pea, is increasingly being explored for medical purposes and the development of a wide range of processed products. This study aimed to incorporate Butterfly pea into an innovative probiotic drink through a symbiotic culture of bacteria and yeast (SCOBY) fermentation and to evaluate the biological activity. The benefits of the drink, referred to as butterfly pea flower kombucha (KBPF) was determined in vitro and in metabolically disorder mice that receive a diet rich in cholesterol and fat (CFED). Forty white male were categorized into four groups, i.e., A = Control/Normal Diet; B = CFED alone; C = CFED + KBPF 65 mg/kg BW (Body Weight); D = CFED + KBPF 130 mg/kg BW, and then sacrificed after 6 weeks of intervention. Seventy-nine secondary metabolite compounds were successfully identified in KBPF using LC-HRMS. In vitro studies showed the potential activity of KBPF in inhibiting not only ABTS, but also lipid (lipase) and carbohydrate (α-amylase, α-glucosidase) hydrolyzing enzymes to levels similar to acarbose control at 50–250 μg/mL. In the in vivo study, the administration of KBPF (130 mg/kg BW) significantly alleviated metabolic disorders caused by high-fat diet. Specifically, lipid profile (HDL, LDL, TC, TG), blood glucose, markers of oxidative stress (SOD liver), metabolic enzymes (lipase, amylase), and markers of inflammation (PGC-1α, TNF-α, and IL-10) were in most cases restored to normal values. Additionally, the gut microbiota community analysis showed that KBPF has a positive effect (p = 0.01) on both the Bacteroidetes phylum and the Firmicutes phylum. The new KBPF drink is a promising therapeutic functional food for preventing metabolic diseases.

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Clitoria ternatea or Butterfly pea flower processed or innovated into a functional probiotic drink, namely KBPF.

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A total of 79 Secondary metabolite compounds of KBPF were successfully identified.

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In vitro studies showed the potential activity of KBPF in inhibiting ABTS, lipase, α-glucosidase, and α-amylase.

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Administering a dose of 130 mg/kg BW KBPF was significantly promising in the alleviation of biomarker metabolic disorders with immunomodulatory effects.

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By modulating the diversity of the gut microbiome, KBPF can be a promising nutraceutical in preventing metabolic syndrome with inflammatory diseases.

Nerve Growth Factor, Stress and Diseases

Stress is a constant threat for homeostasis and is represented by different extrinsic and intrinsic stimuli (stressors, Hans Selye's "noxious agents"), such as aggressive behavior, fear, diseases, physical activity, drugs, surgical injury, and environmental and physiological changes. Our organisms respond to stress by activating the adaptive stress system to activate compensatory responses for restoring homeostasis. Nerve Growth Factor (NGF) was discovered as a signaling molecule involved in survival, protection, differentiation, and proliferation of sympathetic and peripheral sensory neurons. NGF mediates stress with an important role in translating environmental stimuli into physiological and pathological feedbacks since NGF levels undergo important variations after exposure to stressful events. Psychological stress, lifestyle stress, and oxidative stress are well known to increase the risk of mental disorders such as schizophrenia, major depressive disorders, bipolar disorder, alcohol use disorders and metabolic disorders such as metabolic syndrome. This review reports recent works describing the activity of NGF in mental and metabolic disorders related to stress.

The role of oxidant-antioxidant markers and resistin in metabolic syndrome elderly individuals

In elderly, hormones and oxidant-antioxidant interplay are suggested to mediate biochemical balance between adipose tissue to other tissues. Thus the study attempts to explore metabolic traits, plasma resistin, and oxidant-antioxidant markers in metabolic syndrome (MetS) in comparison to non-metabolic syndrome (non-MetS) elderly individuals. A total of 541 healthy elderly Caucasians, with no acute and/or chronic disorders were invited. After taking into account inclusion/exclusion criteria's the MetS was defined as the presence of three out of five abnormal findings and allowed to divided groups into: non-metabolic syndrome, non-MetS (n = 25, median age 69.0 years), and newly diagnosed MetS (n = 29; median age 70.5 years) individuals. Glucose, plasma lipids, resistin (Res), thiobarbituric acid-reacting substances (TBARS), total antioxidant status (TAS), and Cu,Zn-superoxide dismutase (SOD-1) were measured. The MetS had higher resistin than non-MetS (p < 0.04). The linear correlation (all at p < 0.05) showed correlation for Res&triacylglycerols (R = 0.44), and for Res&diastolic blood pressure (R = -0.58) and for SOD-1&fasting glucose (R = -0.34) in MetS, while in the non-MetS group fasting glucose correlates with Res (R = 0.58) and with TAS (R = -0.43). The multiple regression analysis (alone and in combination) showed that independently from other factors resistin correlated positively with fasting glucose (β = 0.37; R = 0.58; R2 = 0.23; p < 0.01) in all investigated elderly participants. In the MetS resistin correlated negatively with diastolic blood pressure (β = -0.68; R = 0.80; R2 = 0.53; p = 0.0004) moreover in that group TAS correlated negatively with HDL-C (β = -0.71; R = 0.72; R2 = 0.37; p = 0.01). While age correlated negatively with systolic blood pressure (β = -0.60; R = 0.62; R2 = 0.14; p = 0.03) independently from other factors in the non-MetS group. Various metabolic factors contribute to maintain serum resistin and oxidant-antioxidant balance in the elderly people in the presence or absence of MetS. Resistin may serve as a predictor of MetS in the elderly, while strong antioxidant defense interactions in older individuals may indicate good health.

Daily consumption effects of probiotic yogurt containing Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 on oxidative stress in metabolic syndrome patients

BACKGROUND AND AIMS

Available evidence substantiates a strong association between metabolic syndrome and elevated oxidative stress. This study was aimed to assess the effects of probiotic yogurt containing Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 on the oxidative stress biomarkers in patients with metabolic syndrome. Furthermore, the association between uric acid levels and insulin resistance indexes was assessed.

METHODS

An 8-week randomized, double-blind, placebo-controlled, parallel study was designed. Forty-four patients, 22 males and 22 females aged 20-65 years, were assigned into two groups. Treatment (n = 22) and control (n = 22) groups consumed 300 g/d of probiotic and regular yogurt, respectively. The serum concentration of uric acid, oxidized Low-Density Lipoprotein (oxLDL), Malondialdehyde (MDA) and Total Antioxidant Capacity (TAC) were measured at the beginning and the end of the trial. This study was recorded at http://www.irct.ir (code: IRCT201608213140N17).

RESULTS

Probiotic yogurt consumption resulted in a significant decrease in the level of serum uric acid and a significant increase in the level of TAC (p < 0.05). A positive significant association between uric acid with insulin concentration and the homeostasis model assessment of insulin resistance (HOMA-IR) and an inverse significant relationship with insulin sensitivity (Quicki) were also found (p < 0.05).

CONCLUSION

Probiotic yogurt consumption through improvement in insulin sensitivity may exert positive effects on the oxidative stress and uric acid levels. However, further studies are needed to make concise conclusions.

The Role of microRNAs in Metabolic Syndrome-Related Oxidative Stress

Oxidative stress (OxS) is the cause and the consequence of metabolic syndrome (MetS), the incidence and economic burden of which is increasing each year. OxS triggers the dysregulation of signaling pathways associated with metabolism and epigenetics, including microRNAs, which are biomarkers of metabolic disorders. In this review, we aimed to summarize the current knowledge regarding the interplay between microRNAs and OxS in MetS and its components. We searched PubMed and Google Scholar to summarize the most relevant studies. Collected data suggested that different sources of OxS (e.g., hyperglycemia, insulin resistance (IR), hyperlipidemia, obesity, proinflammatory cytokines) change the expression of numerous microRNAs in organs involved in the regulation of glucose and lipid metabolism and endothelium. Dysregulated microRNAs either directly or indirectly affect the expression and/or activity of molecules of antioxidative signaling pathways (SIRT1, FOXOs, Keap1/Nrf2) along with effector enzymes (e.g., GPx-1, SOD1/2, HO-1), ROS producers (e.g., NOX4/5), as well as genes of numerous signaling pathways connected with inflammation, insulin sensitivity, and lipid metabolism, thus promoting the progression of metabolic imbalance. MicroRNAs appear to be important epigenetic modifiers in managing the delicate redox balance, mediating either pro- or antioxidant biological impacts. Summarizing, microRNAs may be promising therapeutic targets in ameliorating the repercussions of OxS in MetS.

Improved diagnostic value by combining plasma PON1 level with tumor biomarkers in Colorectal Cancer patients

The incidence of colorectal cancer (CRC) ranks third among all cancers in China and improvements in screening for CRC have an important impact on prevention and control of the disease. Paraoxonase 1 (PON1) is a calcium ion-dependent hydrolase that is widely distributed in tissue. Its diagnostic value in colorectal cancer has been reported, but the diagnostic value of combining PON1 with carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 12-5 (CA12-5) in colorectal cancer has not been evaluated. Experiments were carried out in a total of 284 CRC patients and 90 healthy controls. The primary cohort was randomly divided into training and validation sets. The levels of PON1 in plasma of CRC patients were significantly lower than that in the healthy controls (P < 0.001). It showed excellent diagnostic value with the AUC reaching 0.750 for the training set and 0.742 for the validation set. Furthermore, combining PON1 with CEA, CA12-5, CA19-9 could better classify CRC patients (AUC rising from 0.821, 0.716, 0.712 to 0.875, 0.817 and 0.814, respectively, in the training set, from 0.818, 0.581, 0.593 to 0.854, 0.770, and 0.772 in the validation set). In conclusion, PON1 can serve as a diagnostic biomarker for CRC and raise the sensitivity and specificity when incorporated with traditional tumor biomarkers.

Biomarkers of Oxidative Stress in Metabolic Syndrome and Associated Diseases

Metabolic syndrome (MS) represents worldwide public health issue characterized by a set of cardiovascular risk factors including obesity, diabetes, dyslipidemia, hypertension, and impaired glucose tolerance. The link between the MS and the associated diseases is represented by oxidative stress (OS) and by the intracellular redox imbalance, both caused by the persistence of chronic inflammatory conditions that characterize MS. The increase in oxidizing species formation in MS has been accepted as a major underlying mechanism for mitochondrial dysfunction, accumulation of protein and lipid oxidation products, and impairment of the antioxidant systems. These oxidative modifications are recognized as relevant OS biomarkers potentially able to (i) clarify the role of reactive oxygen and nitrogen species in the etiology of the MS, (ii) contribute to the diagnosis/evaluation of the disease's severity, and (iii) evaluate the utility of possible therapeutic strategies based on natural antioxidants. The antioxidant therapies indeed could be able to (i) counteract systemic as well as mitochondrial-derived OS, (ii) enhance the endogenous antioxidant defenses, (iii) alleviate MS symptoms, and (iv) prevent the complications linked to MS-derived cardiovascular diseases. The focus of this review is to summarize the current knowledge about the role of OS in the development of metabolic alterations characterizing MS, with particular regard to the occurrence of OS-correlated biomarkers, as well as to the use of therapeutic strategies based on natural antioxidants.

The Characteristics and Roles of Advanced Oxidation Protein Products in Atherosclerosis

Advanced oxidation protein products (AOPPs) are novel biomarkers of oxidative damage to proteins and a novel class of inflammatory mediators. AOPPs can promote oxidative stress (OS) and inflammation and thus participate in many pathophysiological disease processes. Atherosclerosis is a chronic inflammatory disease of blood vessels that is characterized by low-density lipoprotein infiltration into the endothelial intima and the formation of atherosclerotic plaques. Inflammation and OS are established risk factors for the formation of atherosclerosis. Accumulated studies show that AOPPs can accelerate the progression of atherosclerosis through OS and inflammation. Additionally, AOPPs can accelerate the formation of atherosclerotic plaques by inhibiting high-density lipoprotein receptor scavenger receptor class B type I-mediated high-density lipoprotein cholesterol reverse transport, leading to metabolic disturbances. Some studies have suggested that plasma AOPPs levels are independently positively correlated with blood pressure and are also independent risk factors for cardiovascular disease. AOPPs can trigger oxidative bursts of neutrophils, monocytes and phagocytic cells, increase the generation of reactive oxygen species and promote the secretion of cytokines to accelerate endothelial cell injury. Detecting the levels and inhibiting the formation of AOPPs may provide a novel approach to monitor the progress and improve the prognosis of atherosclerosis.

Metabolic syndrome and C reactive protein in patients undergoing angiography: Inevitable association?

BACKGROUND

The Metabolic Syndrome (MS) is characterized by a set of risk factors, which causes metabolic and inflammatory changes that increase vascular risk and may promote the development of atherosclerosis. Changes in lifestyle are related to obesity and associated diseases such as hypertension, type 2 diabetes mellitus, MS and cardiovascular disease (CVD).

AIMS

This study aimed to evaluate the relationship of MS components and high sensitivity C Reactive Protein (hsCRP) in patients undergoing arteriography.

METHODS

A group of patients undergoing arteriography was recruited in order we could evaluate the metabolic profile, levels of hsCRP and number of obstructions in the arteries.

RESULTS

Most of our patients underwent arteriography are more likely to have hypertension, glucose intolerance, dyslipidemia, and central obesity, thus, MS is prevalent in this group. They also tend to exhibit higher values of hsCRP, lower values ​​for the estimative of the size of the LDL-c particle and higher number of obstruction in the arteries.

CONCLUSION

We may say that the improvement of the above parameters could reduce inflammation and oxidative stress and vascular damages what would extend life expectancy and quality of life of this group of patients.

Oxidative stress and metabolic disorders: Pathogenesis and therapeutic strategies

Increased body weight and metabolic disorder including insulin resistance, type 2 diabetes and cardiovascular complications together constitute metabolic syndrome. The pathogenesis of metabolic syndrome involves multitude of factors. A number of studies however indicate, with some conformity, that oxidative stress along with chronic inflammatory condition pave the way for the development of metabolic diseases. Oxidative stress, a state of lost balance between the oxidative and anti-oxidative systems of the cells and tissues, results in the over production of oxidative free radicals and reactive oxygen species (ROS). Excessive ROS generated could attack the cellular proteins, lipids and nucleic acids leading to cellular dysfunction including loss of energy metabolism, altered cell signalling and cell cycle control, genetic mutations, altered cellular transport mechanisms and overall decreased biological activity, immune activation and inflammation. In addition, nutritional stress such as that caused by high fat high carbohydrate diet also promotes oxidative stress as evident by increased lipid peroxidation products, protein carbonylation, and decreased antioxidant system and reduced glutathione (GSH) levels. These changes lead to initiation of pathogenic milieu and development of several chronic diseases. Studies suggest that in obese person oxidative stress and chronic inflammation are the important underlying factors that lead to development of pathologies such as carcinogenesis, obesity, diabetes, and cardiovascular diseases through altered cellular and nuclear mechanisms, including impaired DNA damage repair and cell cycle regulation. Here we discuss the aspects of metabolic disorders-induced oxidative stress in major pathological conditions and strategies for their prevention and therapy.

Mitochondrial Haplogroup T Is Associated with Obesity in Austrian Juveniles and Adults

Background

Recent publications have reported contradictory data regarding mitochondrial DNA (mtDNA) variation and its association with body mass index. The aim of the present study was to compare the frequencies of mtDNA haplogroups as well as control region (CR) polymorphisms of obese juveniles (n = 248) and obese adults (n = 1003) versus normal weight controls (n_juvenile = 266, n_adults = 595) in a well-defined, ethnically homogenous, age-matched comparative cohort of Austrian Caucasians.

Methodology and Principal Findings

Using SNP analysis and DNA sequencing, we identified the nine major European mitochondrial haplogroups and CR polymorphisms. Of these, only the T haplogroup frequency was increased in the juvenile obese cohort versus the control subjects [11.7% in obese vs. 6.4% in controls], although statistical significance was lost after adjustment for sex and age. Similar data were observed in a local adult cohort, in which haplogroup T was found at a significantly higher frequency in the overweight and obese subjects than in the normal weight group [9.7% vs. 6.2%, p = 0.012, adjusted for sex and age]. When all obese subjects were considered together, the difference in the frequency of haplogroup T was even more clearly seen [10.1% vs. 6.3%, p = 0.002, OR (95% CI) 1.71 (1.2–2.4), adjusted for sex and age]. The frequencies of the T haplogroup-linked CR polymorphisms C16294T and the C16296T were found to be elevated in both the juvenile and the adult obese cohort compared to the controls. Nevertheless, no mtDNA haplogroup or CR polymorphism was robustly associated with any of several investigated metabolic and cardiovascular parameters (e.g., blood pressure, blood glucose concentration, triglycerides, cholesterol) in all obese subjects.

Conclusions and Significance

By investigation of this large ethnically and geographically homogenous cohort of Middle European Caucasians, only mtDNA haplogroup T was identified as an obesity risk factor.

Metabolic syndrome, aging and involvement of oxidative stress

The prevalence of the metabolic syndrome, a cluster of cardiovascular risk factors associated with obesity and insulin resistance, is dramatically increasing in Western and developing countries. This disorder consists of a cluster of metabolic conditions, such as hypertriglyceridemia, hyper-low-density lipoproteins, hypo-high-density lipoproteins, insulin resistance, abnormal glucose tolerance and hypertension, that-in combination with genetic susceptibility and abdominal obesity-are risk factors for type 2 diabetes, vascular inflammation, atherosclerosis, and renal, liver and heart diseases. One of the defects in metabolic syndrome and its associated diseases is excess of reactive oxygen species. Reactive oxygen species generated by mitochondria, or from other sites within or outside the cell, cause damage to mitochondrial components and initiate degradative processes. Such toxic reactions contribute significantly to the aging process. In this article we review current understandings of oxidative stress in metabolic syndrome related disease and its possible contribution to accelerated senescence.

Low serum high density lipoprotein cholesterol concentration is an independent predictor for enhanced inflammation and endothelial activation

BACKGROUND

Inflammation, endothelial activation and oxidative stress have been established as key events in the initiation and progression of atherosclerosis. High-density lipoprotein cholesterol (HDL-c) is protective against atherosclerosis and coronary heart disease, but its association with inflammation, endothelial activation and oxidative stress is not well established.

OBJECTIVES

(1) To compare the concentrations of biomarkers of inflammation, endothelial activation and oxidative stress in subjects with low HDL-c compared to normal HDL-c; (2) To examine the association and correlation between HDL-c and these biomarkers and (3) To determine whether HDL-c is an independent predictor of these biomarkers.

METHODS

422 subjects (mean age±SD = 43.2±11.9 years) of whom 207 had low HDL-c concentrations (HDL-c <1.0 mmol/L and <1.3 mmol/L for males and females respectively) and 215 normal controls (HDL-c ≥1.0 and ≥1.3 mmol/L for males and females respectively) were recruited in this study. The groups were matched for age, gender, ethnicity, smoking status, diabetes mellitus and hypertension. Fasting blood samples were collected for analysis of biomarkers of inflammation [high-sensitivity C-reactive protein (hsCRP) and Interleukin-6 (IL-6)], endothelial activation [soluble Vascular Cell Adhesion Molecule-1 (sVCAM-1), soluble Intercellular Adhesion Molecule-1 (sICAM-1) and E-selectin)] and oxidative stress [F2-Isoprostanes, oxidized Low Density Lipoprotein (ox-LDL) and Malondialdehyde (MDA)].

RESULTS

Subjects with low HDL-c had greater concentrations of inflammation, endothelial activation and oxidative stress biomarkers compared to controls. There were negative correlations between HDL-c concentration and biomarkers of inflammation (IL-6, p = 0.02), endothelial activation (sVCAM-1 and E-selectin, p = 0.029 and 0.002, respectively), and oxidative stress (MDA and F2-isoprostane, p = 0.036 and <0.0001, respectively). Multiple linear regression analysis showed HDL-c as an independent predictor of IL-6 (p = 0.02) and sVCAM-1 (p<0.03) after correcting for various confounding factors.

CONCLUSION

Low serum HDL-c concentration is strongly correlated with enhanced status of inflammation, endothelial activation and oxidative stress. It is also an independent predictor for enhanced inflammation and endothelial activation, which are pivotal in the pathogenesis of atherosclerosis and atherosclerosis-related complications.

Progression from metabolically benign to at-risk obesity in perimenopausal women: a longitudinal analysis of study of women across the nation (SWAN)

BACKGROUND

Little is known about the natural history of progression from a metabolically benign overweight/obese (MBO) to at-risk overweight/obese (ARO) phenotype. Improved understanding would help clinicians focus on controlling risk factors that predispose an obese individual to progression.

METHODS

Using discrete-time proportional hazard modeling on data from the Study of Women's Health Across the Nation (SWAN), we examined the incident progression from MBO (less than two metabolic syndrome abnormalities) to ARO (two or more metabolic syndrome abnormalities) and factors associated with progression over a 7-year period.

RESULTS

Of 866 MBO women at baseline, 43% progressed to the ARO phenotype. Compared with those who remained MBO, those who progressed had higher baseline BMI and a higher prevalence of cardiometabolic abnormalities (elevated glucose, triglycerides, blood pressure and low high-density lipoprotein cholesterol). In multivariable analyses, an increase in body mass index was associated with a modest increase in the risk of progression. Although all cardiometabolic abnormalities were associated with an increased risk, the baseline impaired fasting glucose showed the strongest association with the risk of progression [hazard ratio 3.24; 95% confidence interval 2.10, 4.92; P < .001]. Physical activity played a protective role in decreasing the risk of progression [hazard ratio 0.86; 95% confidence interval 0.80, 0.92; P < .001].

CONCLUSIONS

Increasing obesity and the presence of cardiometabolic abnormalities increase the risk of progression, whereas physical activity is the only lifestyle factor protective against progression from metabolically benign to the at-risk overweight/obese phenotype, a state that is unanimously associated with an elevated risk of cardiovascular morbidity and mortality.

Antioxidants, inflammation and cardiovascular disease

Multiple factors are involved in the etiology of cardiovascular disease (CVD). Pathological changes occur in a variety of cell types long before symptoms become apparent and diagnosis is made. Dysregulation of physiological functions are associated with the activation of immune cells, leading to local and finally systemic inflammation that is characterized by production of high levels of reactive oxygen species (ROS). Patients suffering from inflammatory diseases often present with diminished levels of antioxidants either due to insufficient dietary intake or, and even more likely, due to increased demand in situations of overwhelming ROS production by activated immune effector cells like macrophages. Antioxidants are suggested to beneficially interfere with diseases-related oxidative stress, however the interplay of endogenous and exogenous antioxidants with the overall redox system is complex. Moreover, molecular mechanisms underlying oxidative stress in CVD are not fully elucidated. Metabolic dybalances are suggested to play a major role in disease onset and progression. Several central signaling pathways involved in the regulation of immunological, metabolic and endothelial function are regulated in a redox-sensitive manner. During cellular immune response, interferon γ-dependent pathways are activated such as tryptophan breakdown by the enzyme indoleamine 2,3-dioxygenase (IDO) in monocyte-derived macrophages, fibroblasts, endothelial and epithelial cells. Neopterin, a marker of oxidative stress and immune activation is produced by GTP-cyclohydrolase I in macrophages and dendritic cells. Nitric oxide synthase (NOS) is induced in several cell types to generate nitric oxide (NO). NO, despite its low reactivity, is a potent antioxidant involved in the regulation of the vasomotor tone and of immunomodulatory signaling pathways. NO inhibits the expression and function of IDO. Function of NOS requires the cofactor tetrahydrobiopterin (BH₄), which is produced in humans primarily by fibroblasts and endothelial cells. Highly toxic peroxynitrite (ONOO^-) is formed solely in the presence of superoxide anion (O₂^-). Neopterin and kynurenine to tryptophan ratio (Kyn/Trp), as an estimate of IDO enzyme activity, are robust markers of immune activation in vitro and in vivo. Both these diagnostic parameters are able to predict cardiovascular and overall mortality in patients at risk. Likewise, a significant association exists between increase of neopterin concentrations and Kyn/Trp ratio values and the lowering of plasma levels of vitamin-C, -E and -B. Vitamin-B deficiency is usually accompanied by increased plasma homoycsteine. Additional determination of NO metabolites, BH₄ and plasma antioxidants in patients with CVD and related clinical settings can be helpful to improve the understanding of redox-regulation in health and disease and might provide a rationale for potential antioxidant therapies in CVD.

Markers of increased cardiovascular risk in postmenopausal women: focus on oxidized-LDL and HDL subpopulations

Objective. To evaluate the effect of gender and menopause in cardiovascular risk (CVR) in a healthy population based on both classical and nontraditional markers. Methods. 56 men and 68 women (48 pre- and 20 postmenopause) were enrolled in the study. The following markers were analyzed: blood pressure (BP), body mass index (BMI), waist circumference (WC), glucose, total cholesterol (total-c), triglycerides (TGs), low-density lipoprotein cholesterol (LDL-c), oxidized-LDL (Ox-LDL), HDL-c and subpopulations, paraoxonase-1 activity, hsCRP, uric acid, tumor necrosis factor alpha (TNF-α), adiponectin, vascular endothelial growth factor (VEGF), and intercellular adhesion molecular 1 (ICAM1). Results. Relative to the women, men present significantly increased BMI, WC, BP, glucose, total-c, TGs, LDL-c, Ox-LDL, uric acid, and TNF-α and reduced adiponectin and total and large HDL-c. The protective profile of women is lost after menopause with a significantly increased BMI, WC, BP, glucose, LDL-c, Ox-LDL, hsCRP, and VEGF and decreased total and large HDL-c. Significant correlations were found in women population and in postmenopausal women between Ox-LDL and total, large, and small HDL-c and between TNF-α and total, large, and small HDL-c, LDL-c, and Ox-LDL. Conclusions. Men present higher CVR than women who lost protection after menopause, evidenced by nontraditional markers, including Ox-LDL and HDL subpopulations.

High levels of asymmetric dimethylarginine are strongly associated with low HDL in patients with acute myocardial infarction

Objectives

Low levels of high-density lipoprotein (HDL) cholesterol are associated with an increased risk of acute myocardial infarction possibly through impaired endothelial atheroprotection and decreased nitric oxide (NO) bioavailability. Asymmetric dimethylarginine (ADMA) mediates endothelial function by inhibiting nitric oxide synthase activity. In patients with acute myocardial infarction, we investigated the relationship between serum levels of HDL and ADMA.

Approach and Results

Blood samples from 612 consecutive patients hospitalized for acute MI <24 hours after symptom onset were taken on admission. Serum levels of ADMA, its stereoisomer, symmetric dimethylarginine (SDMA) and L-arginine were determined using high-performance liquid chromatography. Patients with low HDL (<40 mg/dL for men and <50 mg/dL for women) were compared with patients with higher HDL. Most patients (59%) had low HDL levels. Median ADMA levels were markedly higher in the low HDL group (0.69 vs. 0.50 µmole/L, p<0.001). In contrast, SDMA and L-arginine levels were similar for the two groups (p = 0.120 and p = 0.064). Notably, ADMA, but not SDMA or L-arginine, was inversely correlated with HDL (r = −0.311, p<0.001). In stratified analysis, this relationship was only found for low HDL levels (r = −0.265, p<0.001), but not when HDL levels were higher (r = −0.077, p = 0.225). By multivariate logistic regression analysis, ADMA level was strongly associated with low HDL levels (OR(95%CI):6.06(3.48–10.53), p<0.001), beyond traditional confounding factors.

Conclusions

Our large population-based study showed for the first time a strong inverse relationship between HDL and ADMA in myocardial infarction patients, suggesting a functional interaction between HDL and endothelium, beyond metabolic conditions associated with low HDL levels.

Oxidized low-density lipoprotein (oxLDL) plasma levels and oxLDL to LDL ratio - are they real oxidative stress markers in dialyzed patients?

AIMS

Dyslipidemia and oxidative stress are commonly present in patients during maintenance dialysis treatment. However, the significance of oxidized LDL (oxLDL) as a marker of oxidative stress in uremia is still unresolved. The aim of this study was to establish the role of oxLDL and oxLDL/LDL ratio as markers of lipoprotein abnormalities and oxidative stress in the dialyzed patients.

MAIN METHODS

Plasma oxLDL level was measured by ELISA, and oxLDL/LDL ratio was calculated in 106 dialyzed patients and 20 controls. The linkages between oxLDL, oxLDL/LDL ratio and lipid profile and oxidative stress markers malondialdehyde (MDA) and Cu/Zn superoxide dismutase (Cu/Zn SOD) levels were also analyzed.

KEY FINDINGS

OxLDL levels and oxLDL/LDL ratio were similar in hemodialyzed patients and controls, whereas these parameters were lower in peritoneally dialyzed patients when compared to healthy individuals. In contrast, both MDA and Cu/Zn SOD levels were significantly higher in uremics than in controls. oxLDL and oxLDL/LDL ratio positively correlated with lipid profile (except of HDL), whereas there were no positive associations between these parameters and both MDA and Cu/Zn SOD. Multiple regression analysis confirmed that increased oxLDL/HDL and TC/HDL ratios and total cholesterol levels are the parameters which independently predicted oxLDL in dialyzed patients. In the case of oxLDL/LDL ratio, the independent variables were oxLDL/HDL ratio, total cholesterol and HDL levels.

SIGNIFICANCE

oxLDL levels and oxLDL/LDL ratio seem to be the markers of lipoprotein abnormalities rather than the markers of oxidative stress in the population of dialyzed patients.

The metabolic syndrome, oxidative stress, environment, and cardiovascular disease: the great exploration

The metabolic syndrome affects 30% of the US population with increasing prevalence. In this paper, we explore the relationship between the metabolic syndrome and the incidence and severity of cardiovascular disease in general and coronary artery disease (CAD) in particular. Furthermore, we look at the impact of metabolic syndrome on outcomes of coronary revascularization therapies including CABG, PTCA, and coronary collateral development. We also examine the association between the metabolic syndrome and its individual component pathologies and oxidative stress. Related, we explore the interaction between the main external sources of oxidative stress, cigarette smoke and air pollution, and metabolic syndrome and the effect of this interaction on CAD. We discuss the apparent lack of positive effect of antioxidants on cardiovascular outcomes in large clinical trials with emphasis on some of the limitations of these trials. Finally, we present evidence for successful use of antioxidant properties of pharmacological agents, including metformin, statins, angiotensin II type I receptor blockers (ARBs), and angiotensin II converting enzyme (ACE) inhibitors, for prevention and treatment of the cardiovascular complications of the metabolic syndrome.