Participation of white adipose tissue dysfunction on circulating HDL cholesterol and HDL particle size in apparently healthy humans

Effect of Diet on HDL in Obesity

Alterations of plasma lipoprotein levels and oxidative stress are frequently observed in obese patients, including low high-density lipoprotein (HDL) cholesterol (HDL-C) levels and alterations of HDL composition. Dysfunctional HDL with lower antioxidant and anti-inflammatory properties have also been demonstrated in obesity. There is increasing evidence that white adipose tissue (WAT) participates in several metabolic activities and modulates HDL-C levels and function. In obese subjects, the changes in morphology and function of adipose tissue lead to impaired regulatory function and are associated with a state of low-grade chronic inflammation, with increased release of pro-inflammatory adipokines and cytokines. These alterations may affect HDL metabolism and functions; thus, adipose tissue is considered a potential target for the prevention and treatment of obesity. A cornerstone of obesity prevention and therapy is lifestyle modification through dietary changes, which is reflected in the modulation of plasma lipoprotein metabolism. Some dietary components and metabolites directly affect the composition and structure of HDL and modulate its anti-inflammatory and vasoprotective properties. The aims of the review are to summarize the crosstalk between adipocytes and HDL dysfunction in human obesity and to highlight recent discoveries on beneficial dietary patterns as well as nutritional components on inflammation and HDL function in human obesity.

Trends in lipid profiles and control of LDL-C among adults with diabetes in the United States: An analysis of NHANES 2007-2018

BACKGROUND AND AIM

To determine trends in lipid profiles and lipid control in US adults with diabetes and assess variation in these trends across sex and race/ethnicity from 2007 to 2018.

METHODS AND RESULTS

Serial cross-sectional analysis of data from diabetic adults participating in the National Health and Nutrition Examination Survey (NHANES; 2007-2008 to 2017-2018). Among the 6116 participants included (weighted mean age, 61.0 years; 50.7% men), age-adjusted TC (p for trend < 0.001), LDL-C (p for trend < 0.001), TG (p for trend = 0.006), TG/HDL-C (p for trend = 0.014) and VLDL-C (p for trend = 0.015) decreased significantly. Age-adjusted LDL-C levels were consistently higher in women than in men over the study period. Age-adjusted LDL-C improved significantly for diabetic whites and blacks but did not change significantly for the other races/ethnicity. Lipid parameters improved for non-coronary heart disease (CHD) diabetic adults, except for HDL-C, while no lipid parameter significantly changed for diabetic adults with concomitant CHD. Among diabetic adults receiving statin therapy, age-adjusted lipid control remained unchanged from 2007 to 2018, as did adults with concomitant CHD. However, age-adjusted lipid control improved significantly for men (p for trend < 0.01) and diabetic Mexican Americans (p for trend < 0.01). In 2015-2018, female diabetic participants receiving statins had lower odds of achieving lipid control (OR: 0.55; 95% CI: 0.35-0.84; P = 0.006) than men. Differences in lipid control across different races/ethnicities no longer existed.

CONCLUSIONS

Lipid profiles improved in the US adults with diabetes from 2007 to 2018. Although rates of lipid control did not improve nationally in adults receiving statins, these patterns varied by sex and race/ethnicity.

Adipose tissue dysfunction serum markers are associated with high density lipoprotein size and glycation in the early stages of type 2 diabetes

BACKGROUND

High-density lipoproteins (HDLs) have antiatherogenic properties related to their chemical structure. Adipose tissue (AT) influences HDL reverse cholesterol transport and plasma HDL cholesterol levels. However, whether AT dysfunction affects HDL subpopulations and their glycation in early type 2 diabetes (T2D) is still unknown.

OBJECTIVE

To investigate the association of inflammation and AT dysfunction serum markers with the size and glycation of HDLs in normoglycemic, prediabetes, and T2D subjects.

METHODS

We assessed HDL particle size and advanced glycation end-product (AGE) content in HDLs isolated from normoglycemic (n = 17), prediabetes (n = 17), and recently T2D-diagnosed (n = 18) subjects. Insulin, adiponectin, and plasminogen activator inhibitor 1 (PAI-1) were determined using the Bio-Rad Multiplex Platform, and free fatty acids (FFAs) and high sensitivity C-reactive protein (hs-CRP) were determined by standard procedures. The AT insulin resistance (ATIR) index and ATIR/adiponectin and adiponectin/leptin ratios were calculated.

RESULTS

HDL was progressively smaller (nm) and enriched with AGE (mg-BSA-AGE/mg protein) according to the glucose categories: 8.49 and 7.5 in normoglycemic subjects, 8.44 and 12.4 in prediabetic subjects, and 8.32 and 14.3 in T2D subjects (P = 0.033 and P = 0.009 for size and AGE, respectively). In multivariable regression analysis, the ATIR/adiponectin ratio was inversely associated with HDL size (β = -0.257, P = 0.046), and the ATIR ratio was directly associated with HDL glycation (β = 0.387, P = 0.036). In contrast, adiponectin and the adiponectin/leptin ratio were not associated with alterations in HDL particles. Furthermore, HDL size was associated with resistin (β = -0.348, P = 0.007) and PAI-1 (β = -0.324, P = 0.004). HDL and AGE were related to insulin concentrations (β = 0.458, P = 0.015). Analyses were adjusted for age, sex, body mass index, triglycerides, and HDL-cholesterol.

CONCLUSION

HDL size was significantly associated with the ATIR/adiponectin ratio and inflammation, whereas glycation was more strongly related to the ATIR index. These findings have important implications for the management and prevention of cardiovascular disease in T2D patients.

Vitamin D Receptor Is a Sepsis-Susceptibility Gene in Chinese Children

Background

We designed an association study among 267 cases of children with sepsis and 283 healthy controls, by genotyping 9 variants in the VDR gene.

Material/Methods

This was a hospital-based, case-control, genetic association study. In addition to 3 genetic modes of inheritance, haplotype and interaction analyses were employed to examine the prediction of VDR gene for pediatric sepsis. Effect-size estimates are expressed as odds ratio (OR) and 95% confidence interval (CI).

Results

Two variants in the VDR gene, rs2107301 and rs2189480, were found to play a leading role in susceptibility to sepsis in children. The mutant homozygotes of rs2107301 (CC) and rs2189480 (CC) were associated with a reduced risk of sepsis compared with the corresponding wild homozygotes (OR: 0.44 and 0.43, 95% CI: 0.21–0.92 and 0.23–0.81, p: 0.03 and 0.009, respectively). The mutations of rs2107301-C and rs2189480-C alleles were associated with reduced sepsis risk. Haplotype C-C-C-C-C-T-C-A-G in the VDR gene was significantly associated with a 0.59-fold decreased risk of sepsis (95% CI: 0.12–0.76, p: 0.02). In the haplotype–phenotype analysis, significant association was noted for high-density lipoprotein, even after simulation correction (p_sim <0.05).

Conclusions

Taken together, our findings indicate that the VDR gene may be a sepsis-susceptibility gene in Chinese Han children.

Adipose Tissue Insulin Resistance Is Longitudinally Associated With Adipose Tissue Dysfunction, Circulating Lipids, and Dysglycemia: The PROMISE Cohort

OBJECTIVE

To determine the association of adipose tissue insulin resistance with longitudinal changes in biomarkers of adipose tissue function, circulating lipids, and dysglycemia.

RESEARCH DESIGN AND METHODS

Adults at risk for type 2 diabetes in the Prospective Metabolism and Islet Cell Evaluation (PROMISE) cohort had up to four assessments over 9 years (n = 468). Adipose tissue insulin resistance was determined using a novel validated index, Adipo-IR, calculated as the product of fasting insulin and nonesterified fatty acids measured at baseline. Fasting serum was used to measure biomarkers of adipose tissue function (adiponectin and soluble CD163 [sCD163]), circulating lipids (total cholesterol, HDL, LDL, triglyceride [TG]), and systemic inflammation (interleukin-6 [IL-6] and tumor necrosis factor-α [TNF-α]). Incident dysglycemia was defined as the onset of impaired fasting glucose, impaired glucose tolerance, or type 2 diabetes at follow-up. Generalized estimating equation (GEE) models were used to assess the relationship of Adipo-IR with longitudinal outcomes.

RESULTS

GEE analyses showed that elevated Adipo-IR was longitudinally associated with adipose tissue dysfunction (adiponectin -4.20% [95% CI -6.40 to -1.95]; sCD163 4.36% [1.73-7.06], HDL -3.87% [-5.15 to -2.57], TG 9.26% [5.01-13.69]). Adipo-IR was associated with increased risk of incident dysglycemia (odds ratio 1.59 [95% CI 1.09-2.31] per SD increase). Associations remained significant after adjustment for waist circumference and surrogate indices for insulin resistance. There were no significant longitudinal associations of Adipo-IR with IL-6, TNF-α, total cholesterol, or LDL.

CONCLUSIONS

Our findings demonstrate that adipose tissue insulin resistance is prospectively associated with adipose tissue function, HDL, TG, and incident dysglycemia.

Weight loss normalizes enhanced expression of the oncogene survivin in visceral adipose tissue and blood leukocytes from individuals with obesity

BACKGROUND/OBJECTIVES

Survivin is an oncogene associated with a decrease in apoptosis, an increase in tumor growth, and poor clinical outcome of diverse malignancies. A correlation between obesity, cancer, and survivin is reported in the literature. To date, the impact of weight loss on change in survivin levels is understudied. This study was aimed at: (1) comparing survivin levels in adipose tissue (AT) from lean and obese animal models and evaluating changes after weight loss induced by energy restriction and/or exercise; (2) comparing survivin levels in normal weighted and obese humans and evaluating changes in survivin levels after weight loss induced by a very-low-calorie ketogenic diet (VLCKD) or bariatric surgery in AT and/or blood leukocytes (PBL/PBMCs).

SUBJECTS/METHODS

Survivin expression was evaluated in subcutaneous (SAT) and visceral (VAT) AT derived from animal models of monogenic (Zucker rats) and diet-induced obesity (Sprague Dawley rats and C57BL/6J mice) and after a 4-week weight-loss protocol of energy restriction and/or exercise. Plasma was used to measure the inflammatory status. Survivin expression was also evaluated in PBMCs from patients with obesity and compared with normal weight, in PBLs after VLCKD, and in SAT and/or PBLs after bariatric surgery.

RESULTS

Survivin expression was specifically higher in VAT from obese that lean animals, without differences in SAT. It decreased after weight loss induced by energy restriction and correlated with adiposity and inflammatory markers. In humans, the correlation between being obese and higher levels of survivin was confirmed. In obese subjects, survivin levels were reduced following weight loss after either VLCKD or bariatric surgery. Particularly, a decrease in PBMCs expression (not in SAT one) was found after surgery.

CONCLUSIONS

Weight loss is effective in decreasing survivin levels. Also, PBL/PBMC should be regarded as appropriate mirror of survivin levels in VAT for the identification of an obesity-related protumoral microenvironment.