Oxidative stress and insulin resistance: the coronary artery risk development in young adults study

Association of Race With Risk of Incident Cardiovascular Disease, Coronary Heart Disease, Heart Failure, and Stroke

BACKGROUND

In prior studies of cumulative risk factor exposure, self-identified race was independently associated with incident cardiovascular disease (CVD). A recent study suggests clinical, demographic, and socioeconomic factors explain racial differences. We used propensity score matching to study race as an independent incident CVD risk factor.

OBJECTIVES

The purpose of this study was to assess race as an independent risk factor for incident CVD.

METHODS

We analyzed CARDIA (Coronary Artery Risk Development in Young Adults) study data using propensity score matching of White and Black women, and, separately, White and Black men, with respect to known CVD risk factors.

RESULTS

Black men (n = 487), compared to White men (n = 487), had higher risk of CVD (HR: 2.30; 95% CI: 1.36-3.89; P = 0.0014), stroke (HR: 5.00; 95% CI: 1.45-17.3; P = 0.0047), and congestive heart failure (CHF) (HR: 3.60; 95% CI: 1.34-9.70; P = 0.0067). Black women (n = 640), compared to White women (n = 640), had higher CVD risk (HR: 2.36; 95% CI: 1.17-4.78; P = 0.014) and stroke risk (HR: 2.80; 95% CI: 1.01-7.77; P = 0.039) and borderline significantly higher CHF risk (HR: 3.50; 95% CI: 0.73-16.9; P = 0.096). Risk of coronary heart disease did not differ significantly by race in either sex. Multivariable analyses showed racial differences in the associations of multiple risk factors with incident CVD events independent of other known CVD risk factors.

CONCLUSIONS

Propensity score matching analyses demonstrate that race is an independent risk factor for incident CVD and its components, CHF, and stroke. Multivariable analyses suggest racial differences in Black vs White risk factor impact as the possible cause. Reasons for these differences remain to be explored.

The contribution of dietary total antioxidant capacity to type 2 diabetes risk and levels of glycemic biomarkers: a systematic review

BACKGROUND

This study systematically reviewed and analyzed epidemiological evidence regarding the association between dietary total antioxidant capacity (DTAC) and both the risk of developing diabetes and glycemic biomarker levels.

METHODS

We searched the PubMed, Scopus, ScienceDirect, and Google Scholar databases through July 2024 without imposing any date restrictions. Original studies that examined the relationship between DTAC and either the risk of developing diabetes or glycemic biomarker levels-specifically fasting blood glucose (FBG), hemoglobin A1C (HbA1C), insulin, and the homeostatic model assessment for insulin resistance (HOMA-IR)-were eligible for inclusion. After eliminating duplicates and irrelevant records, relevant studies were selected, and data were extracted through rigorous critical analysis.

RESULTS

A total of 32 articles were included in the review. Of the 19 studies that evaluated diabetes risk, 15 reported a lower risk among subjects with higher DTAC values. All 4 studies examining prediabetes risk found lower risk in participants with high DTAC scores. Additionally, significant inverse relationships were observed between DTAC values and FBG (9/15 studies), HbA1C (1/6 studies), insulin (5/6 studies), and HOMA-IR (8/9 studies).

CONCLUSION

The majority of evidence indicates that high adherence to an antioxidant-rich diet may reduce diabetes risk and improve glycemic biomarkers, including FBG, insulin, and HOMA-IR.

Causal relationship between inflammatory cytokines and polycystic ovary syndrome: a bidirectional mendelian randomization study

Polycystic ovary syndrome (PCOS) is defined as a chronic low-grade inflammatory reproductive endocrine disorder. PCOS can induce various metabolic disorders, which are associated with a state of mild and slow-acting inflammation. Nevertheless, the causal relationship between polycystic ovary syndrome and inflammatory factors is uncertain. The causality between inflammatory cytokines and PCOS was analyzed by bidirectional Mendelian randomization (MR) in this current probe. We performed an interactive MR study to assess the causal relationships between 91 inflammatory cytokines and PCOS using Genome Wide Association Study (GWAS) data. We underwent dual-sample MR analysis with inverse variance weights (IVW) as the predominant MR methodology with multiple validity and heterogeneity analyses. MR-Egger, weighted median, simple mode, weighted mode and MR-PRESSO were analyzed as multiple likelihood sensitivity analyses to enhance the final results.The results came out interleukin-1-alpha (IL-1 A) levels (odds ratio [OR] = 1.051, 95% fiducial interval [95% CI] = 1.009-1.095, P = 0.02) and oncostatin-M (OSM) levels ( [OR] = 1.041, [95% CI] = 1.001-1.082, P = 0.04) were positively associated with the development of PCOS. Moreover, interleukin-7 (IL-7) levels ([OR] = 0.935, [95% CI] = 0.884-0.989, P = 0.02); interleukin-15 receptor subunit alpha (IL15RA) levels ([OR] = 0.959, [95% CI] = 0.929-0.99, P = 0.01); and C-X-C motif chemokine 11 (CXCL11) levels ([OR] = 0.959, [95% CI] = 0.922-0.996. P = 0.03) were strongly negatively associated with PCOS. However, we did not find any strong positive results in the reverse analysis, suggesting that although inflammatory factors contribute to the pathogenesis of PCOS, PCOS itself does not trigger inflammatory factor production.Our study provides genetic evidence for the connection between systemic inflammatory regulators and PCOS. Treatments targeting specific inflammatory factors may help to mitigate the risk of PCOS. The levels of five of the 91 inflammatory factors included in this study, namely, IL1A and OSM, were associated with PCOS. IL1A and OSM contribute to the progression of PCOS while IL-7, IL15RA, and CXCL11 levels are negatively correlated with the development of PCOS.

A preconception cohort study of sugar-sweetened beverage consumption and semen quality

BACKGROUND

Dietary factors, including high sugar intake, may have adverse effects on male reproduction. Studies of the association between sugar-sweetened beverage (SSB) intake and semen quality have reported inconsistent results.

OBJECTIVE

We estimated the effects of SSB consumption on semen quality in a North American preconception cohort study.

METHODS

We analyzed baseline data from 690 males (n = 1,247 samples) participating in Pregnancy Study Online (PRESTO) during 2015-2022. Participants aged ≥21 years completed a baseline questionnaire on which they reported information about intake of SSBs, including sodas, energy drinks, sports drinks, and fruit juices. After enrollment, we invited U.S. participants to a semen testing substudy, in which they collected and analyzed two samples using an at-home semen testing kit. We used linear regression models to estimate adjusted percent differences (%D) and 95% confidence intervals (CI) for associations of SSB intake with semen volume, sperm concentration, total sperm count (TSC), motility, and total motile sperm count (TMSC). We used modified Poisson regression models to estimate adjusted risk ratios (RRs) and 95% CIs for the association of SSB intake with World Health Organization semen parameter cut points.

RESULTS

Relative to non-consumers of SSBs, those who consumed ≥7 SSBs/week had lower semen volume (%D = -6, 95% CI: -13, 0), sperm concentration (%D = -22, 95% CI: -38, 0), TSC (%D = -22, 95% CI: -38, -2), motility (%D = -4, 95% CI: -10, 2), and TMSC (%D = -25, 95% CI: -43, -2). High SSB consumers also had greater risks of low sperm concentration (≤16 million/mL; RR = 1.89, 95% CI: 1.11, 3.21), low TSC (≤39 million; RR = 1.75, 95% CI: 0.92, 3.33), low motility (≤42%; RR = 1.23, 95% CI: 0.87, 1.75) and low TMSC (≤21 million; RR = 1.95, 95% CI: 1.12, 3.38). Associations were stronger among participants with body mass index ≥ 25 kg/m2.

CONCLUSION

Greater SSB consumption was associated with reduced semen quality in a North American preconception cohort.

Effect of perinatal consumption of low-calorie sweetener on maternal health: A systematic review and meta-analysis

BACKGROUND AND AIMS

Evidence regarding perinatal low-calorie (or artificial) sweetener (LCS) consumption and its effect on maternal health outcomes is limited and inconclusive. The primary outcomes of our systematic review and meta-analysis were the effect of preconception and pregnancy LCS exposure on reproductive and pregnancy outcomes. Secondary outcomes included long-term maternal health.

METHODS

A systematic search of electronic databases, including PubMed, Embase, CINAHL, the Cochrane Library, Scopus, Web of Science, PsycINFO, ProQuest Health and Medical, ClinicalTrials.gov and Google Scholar, was conducted up to 20 November 2023. Primary studies, including clinical trials, cohort studies, case-control studies, which reported any LCS consumption during perinatal period and pregnancy and maternal health outcomes were eligible. A random effects model with restricted maximum likelihood estimation was used for the meta-analysis. We appraised the quality of the included studies using the National Institute of Health study quality appraisal tool and the overall quality of evidence using the Grading of Recommendations Assessment, Development, and Evaluation tool.

RESULTS

A total of 19 eligible studies with 203,706 participants were included. LCS consumption during pregnancy was associated with 11% increased risk of preterm birth (RR = 1.11, 95% CI: 1.07-1.16, I2 = 0.01%) and 42% increased risk of gestational diabetes (RR = 1.42, 95% CI: 0.98-2.04, I2 = 67.60%) compared with no consumption, however, the effect size for gestational diabetes was not precise as the 95% CI indicated that the effect estimate could range from 2% lower risk to 204% (or 2.04 times) higher risk. We found no association between LCS consumption during pregnancy and gestational weight gain (standardized mean difference (SMD) = 0.04; 95% CI: -0.17 - 0.24, I2 = 41.31%) or gestational age at birth (SMD = 0.00; 95% CI: -0.13 - 0.14, I2 = 80.13%). The effect of LCS consumption on reproductive treatment outcomes were inconsistent.

CONCLUSIONS

Based on the evidence available, LCS consumption in pregnancy was associated with increased risk of preterm birth and gestational diabetes. Robust research, such as well-designed randomized trials and large prospective cohort studies, is required to confirm the causal effect of LCS consumption during perinatal period on adverse maternal health outcomes.

Single-Atom Ce-N-C Nanozyme Ameliorates Type 2 Diabetes Mellitus by Improving Glucose Metabolism Disorders and Reducing Oxidative Stress

Type 2 diabetes mellitus (T2DM) as a chronic metabolic disease has become a global public health problem. Insulin resistance (IR) is the main pathogenesis of T2DM. Oxidative stress refers to an imbalance between free radical production and the antioxidant system, causing insulin resistance and contributing to the development of T2DM via several molecular mechanisms. Besides, the reduction in hepatic glycogen synthesis also leads to a decrease in peripheral insulin sensitivity. Thus, reducing oxidative stress and promoting glycogen synthesis are both targets for improving insulin resistance and treating T2DM. The current study aims to investigate the pharmacological effects of single-atom Ce-N-C nanozyme (SACe-N-C) on the improvement of insulin resistance and to elucidate its underlying mechanisms using HFD/STZ-induced C57BL/6J mice and insulin-resistant HepG2 cells. The results indicate that SACe-N-C significantly improves hepatic glycogen synthesis and reduces oxidative stress, as well as pancreatic and liver injury. Specifically, compared to the T2DM model group, fasting blood glucose decreased by 29%, hepatic glycogen synthesis increased by 17.13%, and insulin secretion increased by 18.87%. The sod and GPx in the liver increased by 17.80% and 25.28%, respectively. In terms of mechanism, SACe-N-C modulated glycogen synthesis through the PI3K/AKT/GSK3β signaling pathway and activated the Keap1/Nrf2 pathway to alleviate oxidative stress. Collectively, this study suggests that SACe-N-C has the potential to treat T2DM.

Systolic blood pressure and risk of cardiovascular disease in normotensive diabetic adults: a prospective cohort study

BACKGROUND

Currently, the special blood pressure (BP) target for normotensive diabetic patients has not been recommended. We investigated the optimal systolic blood pressure (SBP) for lower cardiovascular disease (CVD) risk in normotensive diabetic patients.

METHODS

In this 12-year follow-up study using the participants of the Kailuan Study, we mainly compared which SBP, 90-119 mmHg or 120-129 mmHg, had a lower risk of occurrence of CVD (stroke and myocardial infarction) in the 3072 normotensive diabetic participants and 21,532 normotensive and non-diabetic participants, respectively. The SBP was expressed as a mean time-weighted cumulative (MTWC) SBP, calculated from the multiple measurements of SBP during the follow-up. Multivariate competing risk regression analyses were used for the analysis.

RESULTS

We found that in normotensive diabetic participants, MTWC SBP of 120-129 mmHg was associated with a lower risk of CVD (HR = 0.69 [0.50-0.95]), myocardial infarction (HR = 0.48 [0.24-0.96]), and trending towards lower risk of stroke (HR = 0.80 [0.55-1.16]), compared to MTWC SBP of 90-119 mmHg. Sensitivity analyses confirmed the relationship between low SBP and increased CVD risk. Whereas, in the normotensive and non-diabetic participants, MTWC SBP of 90-119 mmHg vs 120-129 mmHg did not exhibit any difference in the risk of CVD occurrence (HR = 0.99 [0.83-1.18]).

CONCLUSIONS

The higher level of SBP in normotensive diabetic patients is especially associated with a lower risk of CVD occurrence.

The additive effect of the triglyceride-glucose index and estimated glucose disposal rate on long-term mortality among individuals with and without diabetes: a population-based study

BACKGROUND

The triglyceride-glucose (TyG) index and estimated glucose disposal rate (eGDR), which are calculated using different parameters, are widely used as markers of insulin resistance and are associated with cardiovascular diseases and prognosis. However, whether they have an additive effect on the risk of mortality remains unclear. This study aimed to explore whether the combined assessment of the TyG index and eGDR improved the prediction of long-term mortality in individuals with and without diabetes.

METHODS

In this cross-sectional and cohort study, data were derived from the National Health and Nutrition Examination Survey (NHANES) 2001-2018, and death record information was obtained from the National Death Index. The associations of the TyG index and eGDR with all-cause and cardiovascular mortality were determined by multivariate Cox regression analysis and restricted cubic splines.

RESULTS

Among the 17,787 individuals included in the analysis, there were 1946 (10.9%) all-cause deaths and 649 (3.6%) cardiovascular deaths during a median follow-up of 8.92 years. In individuals with diabetes, the restricted cubic spline curves for the associations of the TyG index and eGDR with mortality followed a J-shape and an L-shape, respectively. The risk of mortality significantly increased after the TyG index was > 9.04 (all-cause mortality) or > 9.30 (cardiovascular mortality), and after eGDR was < 4 mg/kg/min (both all-cause and cardiovascular mortality). In individuals without diabetes, the association between eGDR and mortality followed a negative linear relationship. However, there was no association between the TyG index and mortality. Compared with individuals in the low TyG and high eGDR group, those in the high TyG and low eGDR group (TyG > 9.04 and eGDR < 4) showed the highest risk for all-cause mortality (hazard ratio [HR] = 1.592, 95% confidence interval [CI] 1.284-1.975) and cardiovascular mortality (HR = 1.683, 95% CI 1.179-2.400) in the overall population. Similar results were observed in individuals with and without diabetes.

CONCLUSIONS

There was a potential additive effect of the TyG index and eGDR on the risk of long-term mortality in individuals with and without diabetes, which provided additional information for prognostic prediction and contributed to improving risk stratification.

Nutritional load in post-prandial oxidative stress and the pathogeneses of diabetes mellitus

Diabetes mellitus affected more than 500 million of people globally, with an annual mortality of 1.5 million directly attributable to diabetic complications. Oxidative stress, in particularly in post-prandial state, plays a vital role in the pathogenesis of the diabetic complications. However, oxidative status marker is generally poorly characterized and their mechanisms of action are not well understood. In this work, we proposed a new framework for deep characterization of oxidative stress in erythrocytes (and in urine) using home-built micro-scale NMR system. The dynamic of post-prandial oxidative status (against a wide variety of nutritional load) in individual was assessed based on the proposed oxidative status of the red blood cells, with respect to the traditional risk-factors such as urinary isoprostane, reveals new insights into our understanding of diabetes. This new method can be potentially important in drafting guidelines for sub-stratification of diabetes mellitus for clinical care and management.

SRSF1 Is Required for Mitochondrial Homeostasis and Thermogenic Function in Brown Adipocytes Through its Control of Ndufs3 Splicing

RNA splicing dysregulation and the involvement of specific splicing factors are emerging as common factors in both obesity and metabolic disorders. The study provides compelling evidence that the absence of the splicing factor SRSF1 in mature adipocytes results in whitening of brown adipocyte tissue (BAT) and impaired thermogenesis, along with the inhibition of white adipose tissue browning in mice. Combining single-nucleus RNA sequencing with transmission electron microscopy, it is observed that the transformation of BAT cell types is associated with dysfunctional mitochondria, and SRSF1 deficiency leads to degenerated and fragmented mitochondria within BAT. The results demonstrate that SRSF1 effectively binds to constitutive exon 6 of Ndufs3 pre-mRNA and promotes its inclusion. Conversely, the deficiency of SRSF1 results in impaired splicing of Ndufs3, leading to reduced levels of functional proteins that are essential for mitochondrial complex I assembly and activity. Consequently, this deficiency disrupts mitochondrial integrity, ultimately compromising the thermogenic capacity of BAT. These findings illuminate a novel role for SRSF1 in influencing mitochondrial function and BAT thermogenesis through its regulation of Ndufs3 splicing within BAT.

Kaempferol ameliorates metabolic syndrome by inhibiting inflammation and oxidative stress in high-fat diet-induced obese mice

BACKGROUND/OBJECTIVES

Kaempferol (Ka) is one of the most widely occurring flavonoids found in large amounts in various plants. Ka has anti-obesity, antioxidant, and anti-inflammatory effects. Despite the numerous papers documenting the efficacy of Ka, some controversy remains. Therefore, this study examined the impact of Ka using 3T3-L1 and high-fat diet-induced obese mice.

MATERIALS/METHODS

3T3-L1 cells were treated with 50 μM Ka from the initiation of 3T3-L1 differentiation at D0 until the completion of differentiation on D8. Thirty male mice (C57BL/6J, 4 weeks old) were divided into 3 groups: normal diet (ND), high-fat diet (HFD), and HFD + 0.02% (w/w) Ka (Ka) group. All mice were fed their respective diets ad libitum for 16 weeks. The mice were sacriced, and the plasma and hepatic lipid levels, white adipose tissue weight, hepatic glucose level, lipid level, and antioxidant enzyme activities were analyzed, and immunohistochemistry staining was performed.

RESULTS

Ka suppressed the hypertrophy of 3T3-L1 cells, and the Ka-supplemented mice showed a significant decrease in perirenal, retroperitoneal, mesenteric, and subcutaneous fat compared to the HFD group. Ka supplementation in high-fat diet-induced obese mice also improved the overall blood lipid concentration (total cholesterol, non-high-density lipoprotein-cholesterol, phospholipids, and apolipoprotein B). Ka supplementation in high-fat-induced obesity mice reduced hepatic steatosis and insulin resistance by modulating the hepatic lipid (glucose-6-phosphate dehydrogenase, fatty acid synthase, malic enzyme, phosphatidate phosphohydrolase, and β-oxidation) activities and glucose (glucokinase, phosphoenolpyruvate carboxykinase, and G6pase)-regulating enzymes. Ka supplementation ameliorated the erythrocyte and hepatic mitochondrial H2O2 and inflammation levels (plasma tumor necrosis factor-alpha, monocyte chemoattractant protein-1, interleukin-6, and interferon-gamma and fibrosis of liver and epididymal fat).

CONCLUSION

Ka may be beneficial for preventing diet-induced obesity, inflammation, oxidative stress, and diabetes.

Non-alcoholic fatty liver modifies associations of body mass index and waist circumference with cardiometabolic risk: The CARDIA study

Background

Non-alcoholic fatty liver disease (NAFLD) is recognized as a prevalent determinant of cardiometabolic diseases. The association between NAFLD and obesity warrants further research on how NAFLD modifies associations between body mass index (BMI) and Waist circumference (WC) with cardiometabolic risk (CMR).

Objective

This study assessed whether NAFLD modifies associations between BMI and WC with 5-year changes in CMR in 2366 CARDIA study participants.

Methods

Non-contrast CT was used to quantify liver attenuation, with ≤51 Hounsfield Units (HU) used to define NAFLD in the absence of secondary causes of excess liver fat. The dependent variable was the average Z score of fasting glucose, insulin, triglycerides [log], (-) high-density lipoprotein cholesterol (HDL-C), and systolic blood pressure(SBP). Multivariable linear regression was used to estimate the associations between BMI and WC with CMR. Effect modification by NAFLD was assessed by an interaction term between NAFLD and BMI or WC.

Results

The final sample had 539 (23%) NAFLD cases. NAFLD modified the association of BMI and WC with CMR (interaction p < 0.0001 for both). BMI and WC were associated with CMR in participants without NAFLD (p < 0.001), but not among those with NAFLD. Participants with NAFLD and normal BMI and WC had CMR estimates that were higher than those without NAFLD in the obese categories. Among those without NAFLD the 5 years CMR change estimate was 0.09 (95% CI: 0.062, 0.125) for BMI ≥30 kg/m2 compared to -0.06 (-0.092, -0.018) for BMI < 25 kg/m2, and among those with NAFLD, these estimates were 0.15 (0.108, 0.193) and 0.16 (-0.035, 0.363).

Conclusions

NAFLD modifies associations of BMI and WC with CMR. Compared with BMI and WC, NAFLD was more strongly associated with CMR. In the presence of NAFLD, BMI and WC were not associated with CMR. These findings have implications for clinical screening guidelines.

Habitual intake of iron, copper, and zinc and the risk of type 2 diabetes in a prospective cohort: The CAVAS (Cardiovascular Disease Association Study)

BACKGROUND AND AIMS

Unlike iron, evidence of the association between dietary copper and zinc intake and type 2 diabetes (T2D) risk is limited. This study aimed to examine the prospective associations of dietary intake of iron (total, plant-based, and animal-based), copper, and zinc with T2D risk among adults aged ≥40 years.

METHODS AND RESULTS

For 16,666 participants, dietary intakes (baseline, cumulative average, and most recent) of iron, copper, and zinc were calculated from repeated food frequency questionnaires; a modified Poisson regression model with a robust error estimator was conducted. In men, positive associations between T2D and baseline dietary intake of Cu and Zn, cumulative average dietary intake of Fe (total and animal-based), Cu and Zn, and most recent dietary intake of Fe (total, plant-based, and animal-based), Cu, and Zn [most recent diet: for total Fe, IRR(95%CI) = 1.93 (1.41-2.64); for plant-based Fe, 1.56 (1.15-2.11); for animal-based Fe, 1.44 (1.09-1.90); for Cu, 3.17 (2.33-4.30); for Zn, 2.18 (1.64-2.89)] were observed, where as in women, there were positive associations of only cumulative average dietary Zn intake and most recent dietary intake of plant-based Fe, Cu, and Zn [most recent diet: for plant-based Fe, 1.30 (1.01-1.68); for Cu, 1.62 (1.27-2.08); for Zn, 2.07 (1.61-2.66)].

CONCLUSION

Dietary intakes of iron (total, plant-based, and animal-based), copper, and zinc may be positively associated with T2D risk. These positive associations are predominantly observed in most recent diet and appear to be stronger compared to baseline and cumulative average diet.

The Response of Antioxidant Enzymes and Antiapoptotic Markers to an Oral Glucose Tolerance Test (OGTT) in Children and Adolescents with Excess Body Weight

Oxidative stress and apoptosis are involved in the pathogenesis of obesity-related diseases. This observational study investigates the antioxidant and apoptotic markers response to an oral glucose tolerance test (OGTT) in a population of overweight children and adolescents, with normal (NGT) or impaired glucose tolerance (IGT). Glucose, insulin, and C-peptide concentrations, as well as oxidative stress (SOD, GPx3) and apoptotic markers (Apo1fas, cck18), were determined at T = 0, 30, 60, 90, 120, and 180 min after glucose intake during OGTT. The lipid profile, thyroid function, insulin-like growth factor1, leptin, ghrelin, and adiponectin were also measured at baseline. The 45 participants, with a mean age of 12.15 (±2.3) years old, were divided into two subcategories: those with NGΤ (n = 31) and those with IGT (n = 14). The area under the curve (AUC) of glucose, insulin, and C-peptide was greater in children with IGT; however, only glucose differences were statistically significant. SOD and GPx3 levels were higher at all time points in the IGT children. Apo1fas and cck18 levels were higher in the NGT children at most time points, whereas Adiponectin was lower in the IGT group. Glucose increased during an OGTT accompanied by a simultaneous increase in antioxidant factors, which may reflect a compensatory mechanism against the impending increase in oxidative stress in children with IGT.

Oxidative Stress, Atherogenic Dyslipidemia, and Cardiovascular Risk

Oxidative stress is the consequence of an overproduction of reactive oxygen species (ROS) that exceeds the antioxidant defense mechanisms. Increased levels of ROS contribute to the development of cardiovascular disorders through oxidative damage to macromolecules, particularly by oxidation of plasma lipoproteins. One of the most prominent features of atherogenic dyslipidemia is plasma accumulation of small dense LDL (sdLDL) particles, characterized by an increased susceptibility to oxidation. Indeed, a considerable and diverse body of evidence from animal models and epidemiological studies was generated supporting oxidative modification of sdLDL particles as the earliest event in atherogenesis. Lipid peroxidation of LDL particles results in the formation of various bioactive species that contribute to the atherosclerotic process through different pathophysiological mechanisms, including foam cell formation, direct detrimental effects, and receptor-mediated activation of pro-inflammatory signaling pathways. In this paper, we will discuss recent data on the pathophysiological role of oxidative stress and atherogenic dyslipidemia and their interplay in the development of atherosclerosis. In addition, a special focus will be placed on the clinical applicability of novel, promising biomarkers of these processes.

Triglyceride-glucose index is associated with recurrent revascularization in patients with type 2 diabetes mellitus after percutaneous coronary intervention

BACKGROUND

The Triglyceride-glucose (TyG) index, as a surrogate marker of insulin resistance, is independently associated with the severity of coronary artery lesions and the prognosis of coronary heart disease. The investigation aimed to explore the relationship between the TyG index and recurrent revascularization in individuals with type 2 diabetes mellitus (T2DM) resulting from the progression of lesions or in-stent restenosis (ISR) after percutaneous coronary intervention (PCI).

METHOD

A total of 633 patients who met the inclusion and exclusion criteria were enrolled and divided into three groups based on the tertiles of the TyG index. The primary endpoint was recurrent revascularization resulting from the progression of lesions or ISR. All-cause death was considered as the competing risk event. Competing risk analysis and Cox regression analysis for predicting recurrent revascularization after PCI were conducted stepwise. Variables were standardized to make the hazard ratio (HR), subdistribution hazard ratio (SHR) and corresponding 95% CI more consistent prior to being used for fitting the multivariate risk model. The predictive ability of the TyG index was evaluated using several measures, including the ROC curve, likelihood ratio test, Akaike's information criteria, category-free continuous net reclassification improvement (cNRI > 0), and integrated discrimination improvement (IDI). Internal validation was conducted through bootstrapping with 1000 resamples.

RESULTS

During a median follow-up period of 18.33 months, a total of 64 (10.11%) patients experienced recurrent revascularization, including 55 cases of lesion progression and 9 cases of in-stent restenosis. After controlling for competitive risk events, the TyG index was independently associated with a higher risk of recurrent revascularization [SHR:1.4345, (95% CI 1.1458-1.7959), P = 0.002]. The likelihood ratio test and Akaike's information criteria showed that the TyG index significantly improves the prognostic ability. Additionally, adding the TyG index improved the ability of the established risk model in predicting recurrent revascularization, indicated by a C-index of 0.759 (95% CI 0.724-0.792, P < 0.01), with a cNRI > 0 of 0.170 (95% CI 0.023-0.287, P < 0.05), and an IDI of 0.024 (95% CI 0.009-0.039, P = 0.002). These results remained consistent when the models containing TyG index were confirmed using an internal bootstrap validation method.

CONCLUSION

The findings highlight the potential of the TyG index as a predictor of recurrent revascularization. Lesion progression emerged as the primary contributor to recurrent revascularization instead of in-stent restenosis. The incorporation of the TyG index into risk prediction models is likely to be beneficial for accurate risk stratification in order to improve prognosis.

Serum albumin and risk of incident diabetes and diabetic microvascular complications in the UK Biobank cohort

AIM

To examine the associations between serum albumin and the incidences of diabetes and diabetic microvascular complications in participants of the UK Biobank cohort.

METHODS

There were 398,146 participants without diabetes and 30,952 patients with diabetes from the UK Biobank cohort included in this study. Multivariate-adjusted Cox proportional hazard models were used to analyze the association of albumin with the incidences of diabetes and diabetic microvascular complications. Mendelian randomization (MR) analysis was used to determine the genetic relationships between serum albumin and diabetes.

RESULTS

After a median 12.90 years follow-up, 14,710 participants developed incident diabetes (58.83 ± 7.52 years, 56.10% male). After multivariate adjustment, serum albumin was inversely associated with incident diabetes: hazard ratio (HR) [95% confidence interval] per 10 g/l increase 0.88 [0.82;0.94]. MR analyses suggested a potential genetic influence of serum albumin on diabetes in both the UK Biobank and the FinnGen consortium: odds ratios (ORs) [95% confidence interval per 1 g/l increase 0.99 [0.98;1.00] and 0.78 [0.67;0.92], respectively. In patients with diabetes, higher serum albumin levels were significantly associated with lower risk for diabetic microvascular complications. Specifically, per 10 g/l increase in serum albumin, the HRs for diabetic nephropathy, ophthalmopathy, and neuropathy were 0.42 [0.30;0.58], 0.61 [0.52;0.72], and 0.67 [0.51;0.88], respectively.

CONCLUSION

In this large prospective study, serum levels of albumin were inversely associated with the incidences of diabetes and diabetic microvascular complications. These findings underscore the importance of maintaining optimal nutrient status in reducing the risk of diabetes and its complications.

Candesartan, an angiotensin-II receptor blocker, ameliorates insulin resistance and hepatosteatosis by reducing intracellular calcium overload and lipid accumulation

Insulin resistance is a major contributor to the pathogenesis of several human diseases, including type 2 diabetes, hypertension, and hyperlipidemia. Notably, insulin resistance and hypertension share common abnormalities, including increased oxidative stress, inflammation, and organelle dysfunction. Recently, we showed that excess intracellular Ca²⁺, a known pathogenic factor in hypertension, acts as a critical negative regulator of insulin signaling by forming Ca²⁺-phosphoinositides that prevent the membrane localization of AKT, a key serine/threonine kinase signaling molecule. Whether preventing intracellular Ca²⁺ overload improves insulin sensitivity, however, has not yet been investigated. Here, we show that the antihypertensive agent candesartan, compared with other angiotensin-II receptor blockers, has previously unrecognized beneficial effects on attenuating insulin resistance. We found that candesartan markedly reduced palmitic acid (PA)-induced intracellular Ca²⁺ overload and lipid accumulation by normalizing dysregulated store-operated channel (SOC)-mediated Ca²⁺ entry into cells, which alleviated PA-induced insulin resistance by promoting insulin-stimulated AKT membrane localization and increased the phosphorylation of AKT and its downstream substrates. As pharmacological approaches to attenuate intracellular Ca²⁺ overload in vivo, administering candesartan to obese mice successfully decreased insulin resistance, hepatic steatosis, dyslipidemia, and tissue inflammation by inhibiting dysregulated SOC-mediated Ca²⁺ entry and ectopic lipid accumulation. The resulting alterations in the phosphorylation of key signaling molecules consequently alleviate impaired insulin signaling by increasing the postprandial membrane localization and phosphorylation of AKT. Thus, our findings provide robust evidence for the pleiotropic contribution of intracellular Ca²⁺ overload in the pathogenesis of insulin resistance and suggest that there are viable approved drugs that can be repurposed for the treatment of insulin resistance and hypertension.

Association of Incident Cardiovascular Disease With Time Course and Cumulative Exposure to Multiple Risk Factors

BACKGROUND

The quantitative relationship of incident cardiovascular disease (CVD) to lifetime cumulative risk factor exposure is not well understood.

OBJECTIVES

Using CARDIA (Coronary Artery Risk Development in Young Adults) study data, we examined the quantitative associations of cumulative exposure over time to multiple, simultaneously operating risk factors with CVD incidence and the incidence of its components.

METHODS

Regression models were developed quantifying the influence of the time course and severity of multiple CVD risk factors, operating simultaneously, on risk of incident CVD. The outcomes were incident CVD and the incidence of its components: coronary heart disease, stroke, and congestive heart failure.

RESULTS

Our study included 4,958 asymptomatic adults enrolled in CARDIA from 1985 to 1986 (ages 18 to 30 years) who were followed for 30 years. Risk of incident CVD depends on the time course and severity of a series of independent risk factors, the impact of which is mediated by their effects on individual CVD components after age 40 years. Cumulative exposure (AUC vs time) to low-density lipoprotein cholesterol and triglycerides was independently associated with risk of incident CVD. Of the blood pressure variables, areas under the mean arterial pressure vs time curve and the pulse pressure vs time curve were strongly and independently associated with incident CVD risk.

CONCLUSIONS

The quantitative description of the link between risk factors and CVD informs the construction of individualized CVD mitigation strategies, design of primary prevention trials, and assessment of public health impact of risk factor-based interventions.

The Key Role of Mitochondrial Function in Health and Disease

The role of mitochondrial function in health and disease has become increasingly recognized, particularly in the last two decades. Mitochondrial dysfunction as well as disruptions of cellular bioenergetics have been shown to be ubiquitous in some of the most prevalent diseases in our society, such as type 2 diabetes, cardiovascular disease, metabolic syndrome, cancer, and Alzheimer's disease. However, the etiology and pathogenesis of mitochondrial dysfunction in multiple diseases have yet to be elucidated, making it one of the most significant medical challenges in our history. However, the rapid advances in our knowledge of cellular metabolism coupled with the novel understanding at the molecular and genetic levels show tremendous promise to one day elucidate the mysteries of this ancient organelle in order to treat it therapeutically when needed. Mitochondrial DNA mutations, infections, aging, and a lack of physical activity have been identified to be major players in mitochondrial dysfunction in multiple diseases. This review examines the complexities of mitochondrial function, whose ancient incorporation into eukaryotic cells for energy purposes was key for the survival and creation of new species. Among these complexities, the tightly intertwined bioenergetics derived from the combustion of alimentary substrates and oxygen are necessary for cellular homeostasis, including the production of reactive oxygen species. This review discusses different etiological mechanisms by which mitochondria could become dysregulated, determining the fate of multiple tissues and organs and being a protagonist in the pathogenesis of many non-communicable diseases. Finally, physical activity is a canonical evolutionary characteristic of humans that remains embedded in our genes. The normalization of a lack of physical activity in our modern society has led to the perception that exercise is an "intervention". However, physical activity remains the modus vivendi engrained in our genes and being sedentary has been the real intervention and collateral effect of modern societies. It is well known that a lack of physical activity leads to mitochondrial dysfunction and, hence, it probably becomes a major etiological factor of many non-communicable diseases affecting modern societies. Since physical activity remains the only stimulus we know that can improve and maintain mitochondrial function, a significant emphasis on exercise promotion should be imperative in order to prevent multiple diseases. Finally, in populations with chronic diseases where mitochondrial dysfunction is involved, an individualized exercise prescription should be crucial for the "metabolic rehabilitation" of many patients. From lessons learned from elite athletes (the perfect human machines), it is possible to translate and apply multiple concepts to the betterment of populations with chronic diseases.

Catechin Bioavailability Following Consumption of a Green Tea Extract Confection Is Reduced in Obese Persons without Affecting Gut Microbial-Derived Valerolactones

Obesity-related cardiometabolic disorders are driven by inflammation, oxidative stress, and gut dysbiosis. Green tea catechins protect against cardiometabolic disorders by anti-inflammatory, antioxidant, and prebiotic activities. However, whether obesity alters catechin bioavailability remains unknown. We hypothesized that obesity would decrease catechin bioavailability due to altered gut microbiota composition. Obese and healthy persons completed a pharmacokinetics trial in which a confection formulated with green tea extract (GTE; 58% epigallocatechin gallate, 17% epigallocatechin, 8% epicatechin, 6% epicatechin gallate) was ingested before collecting plasma and urine at timed intervals for up to 24 h. Stool samples were collected prior to confection ingestion. Catechins and γ-valerolactones were assessed by LC-MS. Obesity reduced plasma area under the curve (AUC_0-12h) by 24-27% and maximum plasma concentrations by 18-36% for all catechins. Plasma AUC_0-12h for 5'-(3',4'-dihydroxyphenyl)-γ-valerolactone and 5'-(3',4',5'-trihydroxyphenyl)-γ-valerolactone, as well as total urinary elimination of all catechins and valerolactones, were unaffected. ⍺-Diversity in obese persons was lower, while Slackia was the only catechin-metabolizing bacteria that was altered by obesity. Ascorbic acid and diversity metrics were correlated with catechin/valerolactone bioavailability. These findings indicate that obesity reduces catechin bioavailability without affecting valerolactone generation, urinary catechin elimination, or substantially altered gut microbiota populations, suggesting a gut-level mechanism that limits catechin absorption.

Gamma-glutamyl transferase to high-density lipoprotein cholesterol ratio has a non-linear association with non-alcoholic fatty liver disease: A secondary prospective cohort study in non-obese Chinese adults

OBJECTIVE

The evidence for a relationship between the ratio of gamma-glutamyl transferase (GGT) to high-density lipoprotein cholesterol (HDL-c) and non-alcoholic fatty liver disease (NAFLD) is currently inadequate. This study aimed to investigate the relationship between the GGT/HDL-c ratio and NAFLD.

MATERIALS AND METHODS

This study is a prospective cohort study that recruited a total of 11,891 non-obese volunteers in a Chinese hospital from January 2010 to December 2014 in a non-selective manner. The Cox proportional-hazards regression model was then used to investigate the relationship between baseline GGT/HDL-c ratio and the probability of developing NAFLD. The non-linear link between the GGT/HDL-c ratio and NAFLD was identified using a Cox proportional hazards regression with cubic spline functions and smooth curve fitting (cubic spline smoothing). Furthermore, we conducted several sensitivity and subgroup analyses. Data had been uploaded to the DATADRYAD website.

RESULTS

The mean age of study participants was 43.29 ± 14.95 years old, and 6,502 (54.68%) were male. The median (interquartile ranges) of GGT/HDL-c ratio was 15.56 (10.73-23.84). During a median follow-up of 29.35 months, 2028 (17.05%) participants were diagnosed with NAFLD. After adjusting for covariates, the results showed that GGT/HDL-c ratio was positively associated with incident NAFLD (HR = 1.014, 95% CI 1.011-1.017). There was also a non-linear relationship between GGT/HDL-c ratio and NAFLD, and the inflection point of the GGT/HDL-c ratio was 20.35. The effect sizes (HR) on the left and right sides of the inflection point were 1.113 (95% CI 1.096, 1.130) and 1.003 (95% CI 1.000-1.007), respectively. Moreover, the sensitivity analysis demonstrated the robustness of our results. Subgroup analysis showed that GGT/HDL-c ratio was more strongly associated with incident NAFLD in triglyceride (TG) < 1.7 mmol/L participants. In contrast, the weaker association was probed in those with TG ≥ 1.7 mmol/L.

CONCLUSION

The present study reveals a positive and non-linear relationship between the GGT/HDL-c ratio and NAFLD risk in a non-obese Chinese population. GGT/HDL-c ratio is strongly associated with NAFLD when GGT/HDL-c ratio is less than 20.35. Therefore, maintaining the GGT/HDL-c ratio lower than the inflection point is recommended from a treatment perspective.

Diet, Exercise, and the Metabolic Syndrome: Enrollment of the Mitochondrial Machinery

Metabolic syndrome (MS), a cluster of metabolic risk factors, ranging from abdominal obesity, dyslipidaemia, hypertension, type 2 diabetes and non-alcoholic fatty liver disease [...]

Sugar-sweetened beverage intake in relation to reproductive parameters in young men

BACKGROUND

There has been a decrease in sperm concentration in recent years. Concurrently, there were important dietary changes, including an increase in sugar-sweetened beverage intake (SSB). The relation between SSB and male reproduction functions in humans are barely described in the literature.

METHODS

Cross-sectional study with 209 participants (18-23 years old) recruited during one year in Murcia, Spain. All men provided semen and blood samples the same day. SSB consumption was evaluated using a 101-item validated food frequency questionnaire. Reproductive hormones were analysed from serum samples, obtaining levels of follicle-stimulating hormone, inhibin B, luteinizing hormone, estradiol, and testosterone. The evaluation of semen analysis followed the WHO guidelines and consisted of seminal volume, sperm concentration, total sperm count, percentage of morphologically normal sperm, and percentage of motile sperm. SSB intake association with semen parameters and hormone levels were examined using multiple linear regression.

RESULTS

Men in the highest quartile of the SSB intake had a higher percentage of morphologically normal sperm, 37.4% [6.1, 68.3] (p, trend=0.047) and higher estradiol levels (9.5% [-3.5, 22.5] (p, trend=0.047) than those in the first quartile. SSB intake was unrelated to other semen quality parameters or reproductive hormone levels.

CONCLUSIONS

Our results indicate that sperm morphology and estradiol levels may be associated with sugar-sweetened beverage intake. These findings might be explained by physiological metabolism homeostasis, though more studies are required to confirm these results and draw conclusions in other male populations.

Higher NADH Dehydrogenase [Ubiquinone] Iron–Sulfur Protein 8 (NDUFS8) Serum Levels Correlate with Better Insulin Sensitivity in Type 1 Diabetes

Objective: The aim of the study was to evaluate NADH dehydrogenase [ubiquinone] iron–sulfur protein 8 (NDUFS8) serum concentration as a marker of Complex I, and the relationship with insulin resistance in type 1 diabetes mellitus (T1DM). Design and methods: Participants were adults with T1DM, recruited over the course of 1 year (2018–2019). NDUFS8 protein serum concentration was measured using the ELISA test. Insulin resistance was evaluated with indirect marker estimated glucose disposal rate (eGDR). The group was divided on the base of median value of eGDR (higher eGDR—better insulin sensitivity). Results: The study group consists of 12 women and 24 men. Medians of eGDR and NDUFS8 protein concentration are 7.6 (5.58–8.99) mg/kg/min and 2.25 (0.72–3.81) ng/mL, respectively. The group with higher insulin sensitivity has higher NDUFS8 protein serum concentration, lower waist to hip ratio (WHR), body mass index (BMI), and they are younger. A negative correlation is observed between NDUFS8 protein serum concentration and WHR (rs = −0.35, p = 0.03), whereas a positive correlation is observed between NDUFS8 protein serum concentration and eGDR (rs = 0.43, p = 0.008). Univariate logistic regression shows a significant association between insulin sensitivity and lower age, as well as a higher NDUFS8 serum level. A multivariate logistic regression model confirms the significance (AOR 2.38 (1.04–5.48). p = 0.042). Multivariate linear regression confirms a significant association between insulin sensitivity and better mitochondrial function (beta = 0.54, p = 0.003), independent of age, duration of diabetes, and smoking. Conclusions: Higher NDUFS8 protein serum concentration is associated with higher insulin sensitivity among adults with T1DM.

Levels of abdominal adipose tissue and metabolic-associated fatty liver disease (MAFLD) in middle age according to average fast-food intake over the preceding 25 years: the CARDIA Study

BACKGROUND

Higher levels of intra-abdominal adipose tissue (IAAT) comprising visceral adipose tissue (VAT), intermuscular adipose tissue (IMAT), and liver fat are posited drivers of obesity-related chronic disease risk. Fast food is hypothesized to contribute to IAAT patterns.

OBJECTIVES

We quantified levels of abdominal subcutaneous adipose tissue (SAT), IAAT, and odds of metabolic-associated fatty liver disease (MAFLD) in middle age according to average fast-food intake over the preceding 25 y.

METHODS

We analyzed data from the Coronary Artery Risk Development in Young Adults (CARDIA) study. Participants underwent 6 clinical exams and measurements over 25 y with computed tomography-measured VAT, SAT, and IMAT (n = 3156), plus MAFLD defined by liver attenuation (≤40 Hounsfield units) and 1 metabolic abnormality at year 25 (2010, n = 3001, n cases = 302). We estimated means of VAT, SAT, IMAT, and liver attenuation at the year 25 exam according to categories of average fast-food intake over the previous 25 y adjusted for sociodemographic and lifestyle factors and logistic regression to estimate the odds ratio of MAFLD at year 25.

RESULTS

With higher average fast-food intake over 25 y (categorized as follows: never-1×/mo, >1×-3×/mo, 1-<2×/wk, 2-<3×/wk, ≥3×/wk), there were monotonic higher levels of VAT (98.5, 127.6, 134.5, 142.0, 145.5 cm3), P-trend < 0.0001, which were consistent across anthropometrically classified obesity categories. There was a similar pattern with liver fat. There were higher levels of IMAT and SAT with higher fast-food intake (P-trend = 0.003, 0.0002, respectively), with amounts leveling off at ≥2×/wk. In addition, compared with participants who ate fast food never-1×/mo, there were monotonic higher odds of having MAFLD at year 25 with higher average fast-food intake, with participants who ate fast food ≥3×/wk having an OR of MAFLD = 5.18 (95% CI: 2.87, 9.37).

CONCLUSIONS

There were monotonic higher levels of VAT, liver fat, and odds of having MAFLD in middle age according to higher average fast-food intake over the preceding 25 y.

Early Prediction for Prediabetes and Type 2 Diabetes Using the Genetic Risk Score and Oxidative Stress Score

We aimed to use a genetic risk score (GRS) constructed with prediabetes and type 2 diabetes-related single nucleotide polymorphisms (SNPs) and an oxidative stress score (OSS) to construct an early-prediction model for prediabetes and type 2 diabetes (T2DM) incidence in a Korean population. The study population included 549 prediabetes and T2DM patients and 1036 normal subjects. The GRS was constructed using six prediabetes and T2DM-related SNPs, and the OSS was composed of three recognized oxidative stress biomarkers. Among the nine SNPs, six showed significant associations with the incidence of prediabetes and T2DM. The GRS was profoundly associated with increased prediabetes and T2DM (OR = 1.946) compared with individual SNPs after adjusting for age, sex, and BMI. Each of the three oxidative stress biomarkers was markedly higher in the prediabetes and T2DM group than in the normal group, and the OSS was significantly associated with increased prediabetes and T2DM (OR = 2.270). When BMI was introduced to the model with the OSS and GRS, the area under the ROC curve improved (from 69.3% to 70.5%). We found that the prediction model composed of the OSS, GRS, and BMI showed a significant prediction ability for the incidence of prediabetes and T2DM.

3,3′,4,5′-Tetramethoxy-trans-stilbene Improves Insulin Resistance by Activating the IRS/PI3K/Akt Pathway and Inhibiting Oxidative Stress

The potential anti-diabetic effect of resveratrol derivative, 3,3′,4,5′-tetramethoxy-trans-stilbene (3,3′,4,5′-TMS) and its underlying mechanism in high glucose (HG) and dexamethasone (DXMS)-stimulated insulin-resistant HepG2 cells (IR-HepG2) were investigated. 3,3′,4,5′-TMS did not reduce the cell viability of IR-HepG2 cells at the concentrations of 0.5–10 µM. 3,3′,4,5′-TMS increased the potential of glucose consumption and glycogen synthesis in a concentration-dependent manner in IR-HepG2 cells. 3,3′,4,5′-TMS ameliorated insulin resistance by enhancing the phosphorylation of glycogen synthase kinase 3 beta (GSK3β), inhibiting phosphorylation of insulin receptor substrate-1 (IRS-1), and activating phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway in IR-HepG2 cells. Furthermore, 3,3′,4,5′-TMS significantly suppressed levels of reactive oxygen species (ROS) with up-regulation of nuclear factor erythroid 2-related factor 2 (Nrf2) expression. To conclude, the beneficial effect of 3,3′,4,5′-TMS against insulin resistance to increase glucose consumption and glycogen synthesis was mediated through activation of IRS/PI3K/Akt signaling pathways in the IR-HepG2 cells, accomplished with anti-oxidative activity through up-regulation of Nrf2.

Effects of crocin supplementation on inflammatory markers, lipid profiles, insulin and cardioprotective indices in women with PCOS: A randomized, double-blind, placebo-controlled trial

Polycystic ovary syndrome (PCOS) is a multifactorial reproductive condition common in women of reproductive age. Hyperlipidemia, insulin resistance, obesity, and chronic low-grade inflammation are associated with PCOS. In a clinical trial study, women with PCOS were divided into two groups (n = 25 each): the intervention group receiving crocin (15 mg, twice daily) and the control group receiving a placebo. The duration of intervention in both groups was 12 weeks. Pre- and postintervention, demographic information, lipid profile, fasting blood glucose (FBG), fasting insulin, and inflammatory markers (interleukin-6 [IL-6] and tumor necrosis factor-alpha [TNF-α]) were measured. Intervention with crocin significantly increased the mean high-density lipoprotein cholesterol postintervention compared to the placebo group, while exerting a suppressive effect on the increase in mean low-density lipoprotein cholesterol, triglycerides, and cholesterol levels. Intervention with crocin also exerted inhibitory effects on changes in FBG and insulin, so that crocin improved insulin and cardioprotective indices. Finally, despite the increased inflammatory markers (IL-6 and TNF-α) in the placebo group, crocin treatment had protective effects on their increased changes. Thus, crocin supplementation could be considered in the therapeutic targets of women with PCOS.

Incorporation of Oxidized Phenylalanine Derivatives into Insulin Signaling Relevant Proteins May Link Oxidative Stress to Signaling Conditions Underlying Chronic Insulin Resistance

A link between oxidative stress and insulin resistance has been suggested. Hydroxyl free radicals are known to be able to convert phenylalanine (Phe) into the non-physiological tyrosine isoforms ortho- and meta-tyrosine (o-Tyr, m-Tyr). The aim of our study was to examine the role of o-Tyr and m-Tyr in the development of insulin resistance. We found that insulin-induced uptake of glucose was blunted in cultures of 3T3-L1 grown on media containing o- or m-Tyr. We show that these modified amino acids are incorporated into cellular proteins. We focused on insulin receptor substrate 1 (IRS-1), which plays a role in insulin signaling. The activating phosphorylation of IRS-1 was increased by insulin, the effect of which was abolished in cells grown in m-Tyr or o-Tyr media. We found that phosphorylation of m- or o-Tyr containing IRS-1 segments by insulin receptor (IR) kinase was greatly reduced, PTP-1B phosphatase was incapable of dephosphorylating phosphorylated m- or o-Tyr IRS-1 peptides, and the SH2 domains of phosphoinositide 3-kinase (PI3K) bound the o-Tyr IRS-1 peptides with greatly reduced affinity. According to our data, m- or o-Tyr incorporation into IRS-1 modifies its protein–protein interactions with regulating enzymes and effectors, thus IRS-1 eventually loses its capacity to play its role in insulin signaling, leading to insulin resistance.

Blood, saliva and urine maresin-1 and malondialdehyde may be useful biomarker in patients with polycystic ovary syndrome: a prospective study

Background: Maresin-1 (MaR1) plays a major role in many inflammatory disorders. Polycystic ovary syndrome (PCOS) aside from a hormonal disorder, an inflammation might also contribute to PCOS and its metabolic associations. Therefore, the purpose of this prospective study first time was to find out the blood, saliva and urine levels of MaR1 in PCOS patients and evaluate the correlations with other metabolic and hormonal parameters. Methods: Thirty PCOS patients and 30 matched healthy controls were enrolled to prospective case control study. Blood, urine and saliva samples were simultaneously collected from participants after overnight fasting. MaR1 levels in blood, urine and saliva samples were determined by enzyme-linked immunosorbent assay. Ferriman-Gallwey score, anthropometric, hormonal and some other metabolic parameters were also recorded. Regression analysis was preformed to find out the relationship between MaR1, C-reactive protein (CRP) and malondialdehyde (MDA), and hormonal and metabolic parameters. Results: Patients with PCOS compared with control women had higher MDA and CRP and decreased MaR1 levels. Blood, urine and saliva MDA and MaR1 levels were similar and indicated parallel decrease or increase in the PCOS and control groups. Furthermore, regression analysis indicated that blood CRP and MDA was positively associated with luteinizing hormone (LH) and fasting insulin (FI) in PCOS group (p < 0.05) while blood, urine and saliva MaR1 was negatively associated with CRP and MDA. Conclusions: Present results (MaR1, CRP and MDA together) in case of PCOS suggests that decreased MaR1 and elevated MDA and CRP levels in patients with PCOS and may be considered as a useful early biomarker (especially MaR1) in diagnosis of PCOS disease that has not been previously reported and regular monitoring of their levels could be helpful in clinical decisions.

A plasma metabolite score of three eicosanoids predicts incident type 2 diabetes: a prospective study in three independent cohorts

INTRODUCTION

Peptide markers of inflammation have been associated with the development of type 2 diabetes. The role of upstream, lipid-derived mediators of inflammation such as eicosanoids, remains less clear. The aim of this study was to examine whether eicosanoids are associated with incident type 2 diabetes.

RESEARCH DESIGN & METHODS

In the FINRISK (Finnish Cardiovascular Risk Study) 2002 study, a population-based sample of Finnish men and women aged 25-74 years, we used directed, non-targeted liquid chromatography-mass spectrometry to identify 545 eicosanoids and related oxylipins in the participants' plasma samples (n=8292). We used multivariable-adjusted Cox regression to examine associations between eicosanoids and incident type 2 diabetes. The significant independent findings were replicated in the Framingham Heart Study (FHS, n=2886) and DIetary, Lifestyle and Genetic determinants of Obesity and Metabolic syndrome (DILGOM) 2007 (n=3905). Together, these three cohorts had 1070 cases of incident type 2 diabetes.

RESULTS

In the FINRISK 2002 cohort, 76 eicosanoids were associated individually with incident type 2 diabetes. We identified three eicosanoids independently associated with incident type 2 diabetes using stepwise Cox regression with forward selection and a Bonferroni-corrected inclusion threshold. A three-eicosanoid risk score produced an HR of 1.56 (95% CI 1.41 to 1.72) per 1 SD increment for risk of incident diabetes. The HR for comparing the top quartile with the lowest was 2.80 (95% CI 2.53 to 3.07). In the replication analyses, the three-eicosanoid risk score was significant in FHS (HR 1.24 (95% CI 1.10 to 1.39, p<0.001)) and directionally consistent in DILGOM (HR 1.12 (95% CI 0.99 to 1.27, p=0.07)). Meta-analysis of the three cohorts yielded a pooled HR of 1.31 (95% CI 1.05 to 1.56).

CONCLUSIONS

Plasma eicosanoid profiles predict incident type 2 diabetes and the clearest signals replicate in three independent cohorts. Our findings give new information on the biology underlying type 2 diabetes and suggest opportunities for early identification of people at risk.

Association between intake of soft drinks and testicular function in young men

STUDY QUESTION

Is intake of sugar-sweetened beverages (SSB) or artificially sweetened beverages (ASB) associated with testicular function in young men?

SUMMARY ANSWER

Among young men unaware of their semen quality and reproductive hormone levels, intake of SSBs was associated with lower sperm concentration, lower total sperm count, and a lower ratio of serum inhibin-B/FSH.

WHAT IS KNOWN ALREADY

SSBs may adversely impact testicular function, but results are not consistent across studies. Moreover, the associations of ASB, energy-drinks or fruit juices with testicular function are unclear.

STUDY DESIGN, SIZE, DURATION

Young healthy men and unselected for fertility status men enrolled in a cross-sectional study between 2008 and 2017.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 2935 young (median age: 19 years) men enrolled in the study. Intake of SSBs, ASBs, fruit juices, and energy-drinks was assessed with a validated food frequency questionnaire. Testicular function was assessed through conventional semen quality parameters (semen volume, sperm concentration, total count, motility and morphology), testicular volume assessed with ultrasound, and serum reproductive hormone concentrations (total testosterone, free testosterone, E2, inhibin-B, LH, FSH, sex hormone-binding globulin) were measured.

MAIN RESULTS AND THE ROLE OF CHANCE

In multivariable-adjusted analyses, men in the highest category of SSB intake (median: 1.1 servings (∼220 ml)/day) had a 13.2 million/ml lower median sperm concentration (95% CI: -21.0, -5.5) than non-consumers. A similar pattern was observed with total sperm count (-28 million (95% CI: -48, -9)), serum inhibin-B (-12 pg/ml (95% CI: -21, -4)), and inhibin-B/FSH ratio (-9 (95% CI: -18, 0)). The adjusted median difference in sperm concentration and inhibin-B associated with increasing SSB intake by 1 serving (∼200ml)/day at the expense of water was -3.4 million sperm/ml (95% CI: -5.8, -1.0) and -7 pg/ml (95% CI: -11, -3), respectively.

LIMITATIONS, REASONS FOR CAUTION

Inferring causality is limited owing to the cross-sectional design. We adjusted for a number of potential confounders but cannot exclude that unmeasured lifestyle and behavior associated with soft drink intake is associated with testicular function in these young men.

WIDER IMPLICATIONS OF THE FINDINGS

In the largest study to date, intake of SSBs was associated with lower sperm concentration, total sperm count, and serum inhibin-B/FSH ratio, consistent with a direct suppressive effect of SSB intake on testicular function among otherwise healthy men, potentially affecting fertility. However, the observed association between higher SSB intake and lower semen quality does not necessarily imply a decrease in fertility.

STUDY FUNDING/COMPETING INTEREST(S)

Supported by research from the Danish Council for Strategic Research (2101-08-0058), Independent Research Fund Denmark (8020-00218B), European Union (212844), the Kirsten and Freddy Johansen's Foundation (95-103-72087), the Research Fund of the Capital Region of Denmark (A6176), and the NIH (P30DK046200). The authors report no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Salivary Redox Biomarkers in Insulin Resistance: Preclinical Studies in an Animal Model

Insulin resistance (IR) is a condition of impaired tissue response to insulin. Although there are many methods to diagnose IR, new biomarkers are still being sought for early and noninvasive diagnosis of the disease. Of particular interest in laboratory diagnostics is saliva collected in a stress-free, noninvasive, and straightforward manner. The purpose of the study was to evaluate the diagnostic utility of salivary redox biomarkers in preclinical studies in an animal model. The study was conducted on 20 male Wistar rats divided into two equal groups: a standard diet and a high-fat diet (HFD). In all rats fed the HFD, IR was confirmed by an elevated homeostasis model assessment (HOMA-IR) index. We have shown that IR is responsible for the depletion of the enzymatic (↓superoxide dismutase) and nonenzymatic (↓ascorbic acid, ↓reduced glutathione (GSH)) antioxidant barrier at both the central (serum/plasma) and salivary gland (saliva) levels. In IR rats, we also demonstrated significantly higher concentrations of protein/lipid oxidation (↑protein carbonyls, ↑4-hydroxynoneal (4-HNE)), glycation (↑advanced glycation end products), and nitration (↑3-nitrotyrosine) products in both saliva and blood plasma. Salivary nonenzymatic antioxidants and oxidative stress products generally correlate with their blood levels, while GSH and 4-HNE have the highest correlation coefficient. Salivary GSH and 4-HNE correlate with body weight and BMI and indices of carbohydrate metabolism (glucose, insulin, HOMA-IR) and proinflammatory adipokines (leptin, resistin, TNF-α). These biomarkers differentiate IR from healthy controls with very high sensitivity (100%) and specificity (100%). The high diagnostic utility of salivary GSH and 4-HNE is also confirmed by multivariate regression analysis. Summarizing, saliva can be used to assess the systemic antioxidant status and the intensity of systemic oxidative stress. Salivary GSH and 4-HNE may be potential biomarkers of IR progression. There is a need for human clinical trials to evaluate the diagnostic utility of salivary redox biomarkers in IR conditions.

Visit-to-Visit Fasting Glucose Variability in Young Adulthood and Cardiac Structure and Function at Midlife: The CARDIA Study

Glycemic variability was found associated with left ventricular structure and function in type 2 diabetes. But it is still unclear that whether the greater visit-to-visit fasting glucose (FG) variability in young adulthood among the community population is associated with cardiac function alteration and cardiac remodeling at midlife. The community-based prospective cohort study of Coronary Artery Risk in Young Adult (CARDIA) recruited young participants at the baseline age of 18-30 years during the period of 1985-1986 (Year 0). FG was measured at Year 0, 2, 10, 15, 20, and 25. The echocardiographic evaluation of cardiac structure and function was conducted at year 25. A total of 2,600 young adults mean (SD) aged at 24.9 years (3.6) of which 57.3% were women and 46.7% were African Americans had been included in the study. After multivariable adjusted, higher SD of mean FG (SDFG) is associated with lower early peak diastolic septal mitral annular velocity (e') (β [SE], -0.214 [0.080], P < 0.01) and higher E/e' (β [SE], 0.307 [0.094], P < 0.01), and higher coefficient of variation of the mean FG (CVFG) is also associated with lower e' (β [SE], -0.141[0.066], P < 0.05) and higher E/e' (β [SE], 0.204 [0.078], P < 0.01). The higher average real variation of mean FG (ARVFG) is associated with higher E/e' (β [SE], 0.178 [0.085], P < 0.05) and higher left ventricular mass index (LVMI) (β [SE], 1.240 [0.618], P < 0.05). The higher FG variability in young adulthood is associated with the subclinical change of left ventricular (LV) diastolic function at midlife.

Maternal lifestyle and nutritional habits are associated with oocyte quality and ICSI clinical outcomes

RESEARCH QUESTION

Do maternal lifestyle factors influence the incidence of oocyte dimorphisms and outcomes of intracytoplasmic sperm injection (ICSI) cycles?

DESIGN

A total of 752 female patients undergoing an ICSI cycle at a private university-affiliated IVF centre from January 2015 to December 2019 were included in this historical cohort study. Before starting ovarian stimulation, participants completed a questionnaire on cigarette smoking habits, consumption of alcoholic beverages, refined sugar, artificial sweeteners, soft drinks, fruits, legumes and vegetables, milk and dairy, and meat, as well as exercise frequency over the past 6 months. Oocyte morphology was evaluated before ICSI. The influence of maternal lifestyle factors on the incidence of oocyte dimorphisms and ICSI outcomes was evaluated by multivariate general linear models and generalized linear models, adjusted for potential confounders. The main outcome measures were the incidence of oocyte dimorphisms per cycle and clinical outcomes.

RESULTS

Lifestyle factors and nutritional habits such as cigarette smoking, and the consumption of alcohol, refined sugar and artificial sweeteners, were positively associated with incidence of several oocyte dimorphisms and negatively associated with the response to ovarian stimulation and embryo development. Negative relationships were also observed between these habits and clinical outcomes, apart from miscarriage rate, in which positive relationships were observed. Significant negative dose-dependent relationships between these habits and implantation rates were noted (P < 0.001). Alcoholic beverage consumption also showed inverse dose-dependent relationships with clinical pregnancy and live birth rates. Live birth rate was also negatively associated with cigarette smoking, in a dose-dependent manner.

CONCLUSIONS

Poor maternal habits were associated with reduced oocyte quality and ICSI outcomes in this study. Many of these associations were shown to be dose-dependent.

Interaction of miR-146a-5p with oxidative stress and inflammation in complications of type 2 diabetes mellitus in male rats: Anti-oxidant and anti-inflammatory protection strategies in type 2 diabetic retinopathy

OBJECTIVES

This study aimed to evaluate the role of miR-146a-5p in the pathogenesis of diabetic retinopathy and its interaction with oxidative stress and inflammation in the ocular tissue of rats with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

Twenty adult male Sprague Dawley rats (220 ±20 g) were randomly assigned to control and diabetic groups. A high-fat diet was used for three months to induce T2DM which was confirmed by the HOMA-IR index. After that, the levels of glucose and insulin in serum, HOMA-IR as an indicator of insulin resistance, the ocular level of oxidative markers, TNF-α, IL-1β, MIPs, and MCP-1 along with ocular gene expression of NF-κB, Nrf2, and miR-146a-5p were evaluated.

RESULTS

The level of lipid peroxidation along with metabolic and inflammatory factors significantly increased and the antioxidant enzyme activity significantly decreased in diabetic rats (P<0.05). The ocular expression of NF-κB and TNF-α increased and Nrf2, HO-1, and miR-146a-5p expression decreased in diabetic rats (P<0.05). In addition, a negative correlation between miR-146a-5p expression with NF-κB and HOMA-IR and a positive correlation between miR-146a-5p with Nrf2 were observed.

CONCLUSION

It can be concluded that miR-146a-5p may regulate Nrf2 and NF-κB expression and inflammation and oxidative stress in the ocular tissue of diabetic rats.

Elevated plasma succinate levels are linked to higher cardiovascular disease risk factors in young adults

BACKGROUND

Succinate is produced by both host and microbiota, with a key role in the interplay of immunity and metabolism and an emerging role as a biomarker for inflammatory and metabolic disorders in middle-aged adults. The relationship between plasma succinate levels and cardiovascular disease (CVD) risk in young adults is unknown.

METHODS

Cross-sectional study in 100 (65% women) individuals aged 18-25 years from the ACTIvating Brown Adipose Tissue through Exercise (ACTIBATE) study cohort. CVD risk factors, body composition, dietary intake, basal metabolic rate, and cardiorespiratory fitness were assessed by routine methods. Plasma succinate was measured with an enzyme-based assay. Brown adipose tissue (BAT) was evaluated by positron emission tomography, and circulating oxylipins were assessed by targeted metabolomics. Fecal microbiota composition was analyzed in a sub-sample.

RESULTS

Individuals with higher succinate levels had higher levels of visceral adipose tissue (VAT) mass (+ 42.5%), triglycerides (+ 63.9%), C-reactive protein (+ 124.2%), diastolic blood pressure (+ 5.5%), and pro-inflammatory omega-6 oxylipins than individuals with lower succinate levels. Succinate levels were also higher in metabolically unhealthy individuals than in healthy overweight/obese peers. Succinate levels were not associated with BAT volume or activity or with fecal microbiota composition and diversity.

CONCLUSIONS

Plasma succinate levels are linked to a specific pro-inflammatory omega-6 signature pattern and higher VAT levels, and seem to reflect the cardiovascular status of young adults.

Chaya Leaf Decreased Triglycerides and Improved Oxidative Stress in Subjects With Dyslipidemia

Chaya is an edible leaf popular in Mexico and Central America because of its high nutritional value. Studies in animal models have demonstrated the beneficial effects of Chaya, which include reduction of circulating lipids and increase in antioxidant activity. However, its hypolipidemic and antioxidant effects have not been demonstrated in humans. Thus, the aim of the present study was to evaluate the effect of Chaya on the lipid profile, lipid peroxidation, inflammation, and peripheral blood mononuclear cell gene expression in a population with dyslipidemia. We performed a single-arm trial in 30 participants with dyslipidemia who consumed 500 mL of Chaya beverage per day over a 6-week period. Interestingly, we observed a significant decrease in serum triglyceride concentration (P < 0.05) and an increase in plasma antioxidant activity and polyphenol concentration (P < 0.005) after 6 weeks of Chaya consumption. This was accompanied by a reduction in the oxidative stress marker MDA (P < 0.0001) and by an increase in the antioxidant enzyme CAT expression in peripheral blood mononuclear cells (P < 0.001). Altogether, our results demonstrate that consumption of Chaya has hypotriglyceridemic and antioxidant effects in subjects with dyslipidemia.

Association of Oxidative Balance Score with the Metabolic Syndrome in a Sample of Iranian Adults

OBJECTIVE

We aimed to assess the association of the oxidative balance score (OBS) with metabolic syndrome (MetS) in adults.

DESIGN

A population-based cross-sectional study Setting. Health centers from five districts in Tehran, Iran.

METHODS

We recruited 847 participants with an age range of 18-65 years. Dietary intake was assessed by a semiquantitative food frequency questionnaire with 168 items. The OBS was calculated by using the following 13 dietary and nondietary anti- and prooxidant components: dietary antioxidants (selenium, fiber, β-carotene, vitamin D, vitamin C, vitamin E, and folate), dietary prooxidants (iron and saturated and polyunsaturated fatty acids), and nondietary anti- (physical activity) and prooxidants (smoking and obesity). The odds ratio (OR) and 95% confidence interval (CI) of the MetS and its components across tertiles of the OBS were calculated by logistic regression analysis, controlling for age, sex, energy intake, occupation, and educational level.

RESULTS

The range of OBS was between 16 and 39. Being in the top versus the bottom tertile of the OBS was not associated with the MetS (OR = 0.71, 95% CI 0.48-1.03; P = 0.07), after controlling for potential confounders. Higher OBS score was associated with a lower likelihood of abdominal obesity (OR: 0.55, 95% CI: 0.38-0.81; P = 0.003) and increased diastolic blood pressure (OR: 0.64, 95% CI: 0.41-0.99; P = 0.04). Higher OBS was not associated with other components of the MetS.

CONCLUSION

Overall, the present study showed that there was no significant relationship between OBS and MetS in Tehranian adults.

Use of human teardrop fluid for the determination of trace elements in healthy individuals and diabetic patients

BACKGROUND

The use of unconventional biological materials in human trace element studies has increased in terms of published research studies. The aim of present study was to develop and validate the use of teardrop fluid for determining trace element levels in the human body. No study has been published in this area yet. This is a new non-invasive approach in the possible early diagnosis of the pathogenesis of type 2 diabetes.

MATERIALS AND METHODS

Human teardrop fluid samples were obtained from Karbala (Iraq) (n = 111) healthy individuals and with type 2 diabetes (n = 44); and London (UK) healthy individuals (n = 18). The levels of V, Cr, Mn, Fe, Cu, Zn, As, Sr and Cd were determined using an inductively coupled plasma mass equipped with collision cell technology for polyatomic ion correction (ICP-MS).

STATISTICAL ANALYSIS

Discriminate function analysis (DFA) was carried out to determine the set of variables that discriminated between the trace elements in teardrop fluid samples from healthy individuals and diabetic patients.

RESULTS

The trace element levels of human teardrop fluid are similar for many elements to that reported for human blood serum in the literature. This is interesting since they have different physiological functions, although overall they are mainly water containing electrolytes (∼ 90 %) and solids (antibodies, hormones, etc). In general, for the study groups in Karbala, Iraq, significantly higher teardrop fluid levels of Mn and Sr were found in type 2 diabetic patients when compared with healthy individuals (evaluated using an F-test and a two-tailed t-test). The levels of V, Cu and As were found to be significantly higher (P < 0.05) in healthy individuals than type 2 diabetic patients. Although the levels of Fe and Zn were slightly higher in type 2 diabetic patients than healthy cases, the differences were not statistically significant (P > 0.05). Cr and Cd were found to have similar levels for both study groups. Significantly higher teardrop fluid levels of V, Cr, Mn, Fe, Zn, As and Sr were found in healthy individuals from Karbala (Iraq) when compared with those from London (UK). In contrast, the levels of Cd observed to be significantly higher in London (UK) than Karbala. No statistical difference was found for Cu between the two healthy groups.

STATISTICAL ANALYSIS

Discriminate analysis showed that human teardrop fluid V, Mn, Zn, As, Sr and Cd levels could be used to discriminate between healthy and type 2 diabetes study groups in Karbala, Iraq (83 % of cases correctly classified).

CONCLUSION

The use of human teardrop fluid for determining the trace element levels of human health conditions has been evaluated. Trace elemental levels are like that for blood serum which is widely used as an invasive method for assessing human health conditions. Sample collection for teardrop fluid is non-invasive and the application has potential for determining the trace element levels in healthy individuals and disorder conditions (like type 2 diabetes) in countries where cultural and gender sensitivity are issues with respect to the collection methods used for other body fluid samples.

Obesity and aging: Molecular mechanisms and therapeutic approaches

The epidemic of obesity is a major challenge for health policymakers due to its far-reaching effects on population health and potentially overwhelming financial burden on healthcare systems. Obesity is associated with an increased risk of developing acute and chronic diseases, including hypertension, stroke, myocardial infarction, cardiovascular disease, diabetes, and cancer. Interestingly, the metabolic dysregulation associated with obesity is similar to that observed in normal aging, and substantial evidence suggests the potential of obesity to accelerate aging. Therefore, understanding the mechanism of fat tissue dysfunction in obesity could provide insights into the processes that contribute to the metabolic dysfunction associated with the aging process. Here, we review the molecular and cellular mechanisms underlying both obesity and aging, and how obesity and aging can predispose individuals to chronic health complications. The potential of lifestyle and pharmacological interventions to counter obesity and obesity-related pathologies, as well as aging, is also addressed.

Oxidized LDL, insulin sensitivity and beta-cell function in newborns

INTRODUCTION

Oxidized low-density lipoprotein (OxLDL), a biomarker of oxidative stress, itself possesses proatherogenic and proinflammatory effects. Elevated circulating OxLDL levels have been consistently associated with insulin resistance and diabetes in adults. We sought to assess whether OxLDL may be associated with insulin sensitivity and beta-cell function in early life.

RESEARCH DESIGN AND METHODS

In a birth cohort study, we assessed cord plasma OxLDL concentration and OxLDL to total LDL ratio in relation to glucose to insulin ratio (an indicator of fetal insulin sensitivity), proinsulin to insulin ratio (an indicator of fetal beta-cell function), and leptin and adiponectin concentrations in 248 singleton newborns.

RESULTS

Cord plasma OxLDL concentration was positively correlated with glucose to insulin ratio (r=0.24, p<0.001) and proinsulin to insulin ratio (r=0.20, p<0.001) and was not correlated with leptin or adiponectin. Adjusting for maternal and neonatal characteristics, each log unit increase in cord plasma OxLDL concentration was associated with a 25.8% (95% CI 12.8% to 40.3%) increase in glucose to insulin ratio and a 19.0% (95% CI 6.8% to 32.9%) increase in proinsulin to insulin ratio, respectively. Similar associations were observed for cord plasma OxLDL to LDL ratio in relation to cord plasma glucose to insulin ratio and proinsulin to insulin ratio.

CONCLUSIONS

Higher OxLDL levels were associated with lower fetal beta-cell function (higher proinsulin to insulin ratio) but higher insulin sensitivity (higher glucose to insulin ratio). The study is the first to demonstrate that OxLDL may affect glucose metabolic health in early life in humans.

Nutrition, genetic variation and male fertility

Infertility affects nearly 50 million couples worldwide, with 40-50% of cases having a male factor component. It is well established that nutritional status impacts reproductive development, health and function, although the exact mechanisms have not been fully elucidated. Genetic variation that affects nutrient metabolism may impact fertility through nutrigenetic mechanisms. This review summarizes current knowledge on the role of several dietary components (vitamins A, B₁₂, C, D, E, folate, betaine, choline, calcium, iron, caffeine, fiber, sugar, dietary fat, and gluten) in male reproductive health. Evidence of gene-nutrient interactions and their potential effect on fertility is also examined. Understanding the relationship between genetic variation, nutrition and male fertility is key to developing personalized, DNA-based dietary recommendations to enhance the fertility of men who have difficulty conceiving.

Functions of Forkhead Box O on Glucose Metabolism in Abalone Haliotis discus hannai and Its Responses to High Levels of Dietary Lipid

The forkhead box O (FoxO) subfamily is a member of the forkhead transcription factor family. It has regulation functions in glucose metabolism in mammals and fish. In the present study, a gene of the foxo homolog in abalone Haliotis discus hannai was cloned. A conservative forkhead (FH) domain and a transactivation (FoxO-TAD) domain were identified. Abalone foxo-specific siRNA (small interfering RNA) was injected to investigate the functions of foxo on glucose metabolism. Knockdown of foxo inhibited expression of phosphoenolpyruvate carboxykinase (pepck) and significantly increased expressions of hexokinase (hk) and pyruvate kinase (pk), but it failed to inhibit the relative mRNA level of glucose-6-phosphatase (g6pase). Then, a 100-day feeding trial was conducted to investigate the response of foxo and glucose metabolism in abalone fed with 1.57% (LFD, low-fat diet), 3.82% (MFD, middle-fat diet) and 6.72% (HFD, high-fat diet) of dietary lipid, respectively. The insulin-signaling pathway (AKT) was depressed and FoxO was activated by the HFD, but it did not inhibit glycolysis (hk) or improved gluconeogenesis significantly (pepck and g6pase). At the same time, impaired hepatopancreas glycogen storage raised hemolymph glucose levels. In conclusion, abalone foxo can be regulated by dietary lipid and can regulate gluconeogenesis or glycolysis in response to changes of dietary lipid levels, in which glycogen metabolism plays an important role.

Risk of gastrointestinal cancer in patients with an elevated level of gamma-glutamyltransferase: A nationwide population-based study

Emerging evidence that an elevated serum gamma-glutamyltransferase (GGT) level is associated with an increased risk of gastrointestinal cancer, but still controversial. The aim of this study to assess the relationship between GGT level and risk of gastrointestinal cancer, and the contribution of the interaction of hyperglycemia with elevated GGT level to the incidence of gastrointestinal cancer by the stratified analysis. A total of 8,120,665 Koreans who received medical checkups in 2009 were included. Subjects were classified according to the quartile of GGT level for women and men. The incidence rates of gastrointestinal cancer for each group were analyzed using Cox proportional hazards models. During follow-up, 129,853 cases of gastrointestinal cancer newly occurred (esophagus, 3,792; stomach, 57,932; and colorectal, 68,789 cases). The highest GGT quartile group showed an increased risk of gastrointestinal cancer (esophagus, hazard ratio = 2.408 [95% confidence interval, 2.184–2.654]; stomach, 1.121 [1.093–1.149]; and colorectal, 1.185 [1.158–1.211]). The risk increased significantly with the rise in GGT quartile level, regardless of the site of cancer. The stratified analysis according to glycemic status showed that the effect of elevated GGT was predominant in the risk of esophageal cancer. The effect of elevated GGT further increased the risk of stomach and colorectal cancers in diabetic patients. An elevated level of GGT was associated with an increased risk of gastrointestinal cancer, regardless of the site of cancer. The effect of the increase in GGT level on the risk of gastrointestinal cancer depended on the type of cancer and glycemic status.

Time Course of LDL Cholesterol Exposure and Cardiovascular Disease Event Risk

BACKGROUND

Incident cardiovascular disease (CVD) increases with increasing low-density lipoprotein cholesterol (LDL-C) concentration and exposure duration. Area under the LDL-C versus age curve is a possible risk parameter. Data-based demonstration of this metric is unavailable and whether the time course of area accumulation modulates risk is unknown.

OBJECTIVES

Using CARDIA (Coronary Artery Risk Development in Young Adults) study data, we assessed the relationship of area under LDL-C versus age curve to incident CVD event risk and modulation of risk by time course of area accumulation-whether risk increase for the same area increment is different at different ages.

METHODS

This prospective study included 4,958 asymptomatic adults age 18 to 30 years enrolled from 1985 to 1986. The outcome was a composite of nonfatal coronary heart disease, stroke, transient ischemic attack, heart failure hospitalization, cardiac revascularization, peripheral arterial disease intervention, or cardiovascular death.

RESULTS

During a median 16-year follow-up after age 40 years, 275 participants had an incident CVD event. After adjustment for sex, race, and traditional risk factors, both area under LDL-C versus age curve and time course of area accumulation (slope of LDL-C curve) were significantly associated with CVD event risk (hazard ratio: 1.053; p < 0.0001 per 100 mg/dl × years; hazard ratio: 0.797 per mg/dl/year; p = 0.045, respectively).

CONCLUSIONS

Incident CVD event risk depends on cumulative prior exposure to LDL-C and, independently, time course of area accumulation. The same area accumulated at a younger age, compared with older age, resulted in a greater risk increase, emphasizing the importance of optimal LDL-C control starting early in life.

Sex differences in cardiovascular risk factors before and after the development of type 2 diabetes and risk for incident cardiovascular disease

AIMS

To assess sex differences in cardiovascular (CVD) risk factor changes before and after the development of type 2 diabetes, and, the association between incident diabetes with incident CVD in mid-life.

METHODS

We included 4893 Coronary Artery Risk Development in Young Adults Study participants, age 18-30 years at enrollment (1985-86). We ascertained incident diabetes and assessed sex differences in annual change in body mass index, blood pressure, and lipids before and after the ascertainment of diabetes using piecewise linear regression. We examined sex differences in the association between incident diabetes with incident CVD over 31 years of median follow-up.

RESULTS

Progression in most CVD risk factors did not differ by sex before diabetes. Women had better CVD profiles at the time of diabetes compared to men, and after diabetes, women had worse annual changes in blood pressure and lipids. Incident diabetes was associated with a higher hazard for incident CVD (Hazard Ratio [HR]: 1.45, 95% confidence limits: 1.07, 1.96) and we did not observe effect modification by sex (p for interaction = 0.8).

CONCLUSIONS

CVD risk factors worsened more rapidly after the development of type 2 diabetes for women than men. However, diabetes was not a stronger risk factor for incident CVD for women than men.

Pathophysiological roles of chronic low-grade inflammation mediators in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common hormonal imbalance disease in reproductive-aged women. Its basic characteristics are ovulatory dysfunction and ovarian overproduction of androgens that lead to severe symptoms such as insulin resistance, hirsutism, infertility, and acne. Notwithstanding the disease burden, its underlying mechanisms remain unknown, and no causal therapeutic exists. In recent years, further studies showed that inflammation processes are involved in ovulation and play a key role in ovarian follicular dynamics. Visceral adipose tissue can cause inflammatory response and maintenance of the inflammation state in adipocytes by augmented production of inflammatory cytokines, monocyte chemoattractant proteins, and recruitment of the immune cell. Therefore, the PCOS can be related to a low-grade inflammation state and inflammatory markers. Investigating the inflammatory processes and mediators that contribute to the commencement and development of PCOS can be a critical step for better understanding the pathophysiology of the disease and its treatment through inhibition or control of related pathways. In the present review, we discuss the pathophysiological roles of chronic low-grade inflammation mediators including inflammasome-related cytokines, interleukin-1β (IL-1β), and IL-18 in PCOS development.