The Association of Vitamin D Receptor Polymorphisms with COVID-19 Severity

BACKGROUND

Association studies of vitamin D receptor (VDR) polymorphisms with COVID-19 severity have produced inconsistent results in different populations. Herein we examined VDR gene polymorphisms in a Caucasian Greek cohort of COVID-19 patients.

METHODS

This was a case-control study in a tertiary university hospital in Greece including 137 COVID-19 patients with varying disease severities and 72 healthy individuals. In total 209 individuals were genotyped for the FokI (rs10735810), ApaI (rs7975232), TaqI (rs731236) and BsmI (rs1544410) single-nucleotide polymorphisms (SNP) of the VDR gene by polymerase chain reaction and restriction fragment length polymorphism analysis (PCR-RFLPs). Statistical analyses were performed to determine the association between genotype and disease severity, adjusting for various confounding factors.

RESULTS

Genotype distribution of the studied VDR SNPs in the control group was in Hardy-Weinberg equilibrium. The TaqI variant was differentially distributed between controls and COVID-19 patients according to the additive model (p = 0.009), and the CC genotype was significantly associated with an increased risk for severe COVID-19 according to the recessive model [OR: 2.52, 95%CI:1.2-5.29, p = 0.01]. Multivariate analysis demonstrated a robust association of COVID-19 severity and TaqI polymorphism in the recessive model even after adjusting for multiple confounders, including age, sex and CRP levels [Adj.OR:3.23, 95%CI:1.17-8.86, p = 0.023]. The distribution of FokI, ApaI and BsmI genotypes was similar between COVID-19 patients and controls.

CONCLUSIONS

The CC genotype of TaqI polymorphism is significantly associated with an increased risk for severe COVID-19 independently of age, sex or degree of inflammation.

Positive contribution of hydroxytyrosol-enriched wheat bread to HbA1c levels, lipid profile, markers of inflammation and body weight in subjects with overweight/obesity and type 2 diabetes mellitus

PURPOSE

The aim of the present study was to assess the impact of the daily consumption of bread enriched with hydroxytyrosol on HbA₁c and blood lipid levels, inflammatory markers and weight loss.

METHODS

Sixty adults with overweight/obesity and type 2 diabetes mellitus (29 male, 31 female) participated in a 12-week dietary intervention based on the Mediterranean diet and consumed daily 60 g of conventional whole wheat bread (WWB) or whole wheat bread enriched with hydroxytyrosol (HTB). Anthropometric characteristics were measured and venous blood samples were collected at baseline and at the end of the intervention.

RESULTS

Both groups experienced significant weight loss, body fat and waist circumference decrease (p < 0.001). Nonetheless, a greater body fat mass decrease was observed in the HTB group compared to the WWB group (14.4 ± 1.6 vs 10.2 ± 1.1%, p = 0.038). Significant reductions were also reported in fasting glucose, HbA₁c and blood pressure in both groups (p < 0.05). Regarding glucose and HbA₁c, greater decreases were observed in the intervention group (101.4 ± 19.9 vs. 123.2 ± 43.4 mg/dL, p = 0.015 and 6.0 ± 0.6 vs. 6.4 ± 0.9%, p = 0.093, respectively). At HTB group, significant reductions in blood lipid, insulin, TNF-αand adiponectin levels (p < 0.05) and a marginally significant reduction in leptin levels (p = 0.081) were also reported.

CONCLUSION

Enrichment of bread with HT resulted in significant body fat mass reduction and positive effects on fasting glucose, insulin and HbA₁c levels. It also contributed to reductions in inflammatory markers and blood lipid levels. Incorporation of HT in staple foods, like bread, may improve their nutritional profile and, in terms of a balanced diet, may contribute to the management of chronic diseases.

TRIAL REGISTRATION

The study was prospectively registered in clinicaltrials.gov (24th May 2021).

CLINICALTRIALS

gov Identifier: NCT04899791.

Lipidomics Analysis of Free Fatty Acids in Human Plasma of Healthy and Diabetic Subjects by Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS)

Targeted analytical methods for the determination of free fatty acids (FFAs) in human plasma are of high interest because they may help in identifying biomarkers for diseases and in monitoring the progress of a disease. The determination of FFAs is of particular importance in the case of metabolic disorders because FFAs have been associated with diabetes. We present a liquid chromatography-high resolution mass spectrometry (LC-HRMS) method, which allows the simultaneous determination of 74 FFAs in human plasma. The method is fast (10-min run) and straightforward, avoiding any derivatization step and tedious sample preparation. A total of 35 standard saturated and unsaturated FFAs, as well as 39 oxygenated (either hydroxy or oxo) saturated FFAs, were simultaneously detected and quantified in plasma samples from 29 subjects with type 2 diabetes mellitus (T2D), 14 with type 1 diabetes mellitus (T1D), and 28 healthy subjects. Alterations in the levels of medium-chain FFAs (C6:0 to C10:0) were observed between the control group and T2D and T1D patients.

The glycemic status determines the direction of the relationship between red cell distribution width and HbA1c

AIMS

Available studies conducted on heterogenous populations on the association between the erythrocyte distribution width (RDW) and HbA1c have reported a positive, negative or neutral relationship. The aim of the present study is to investigate the debated relationship between RDW and HbA1c among hematologically healthy individuals with and without type 2 diabetes mellitus (T2DM).

METHODS

Paired measurements of RDW and HbA1c of 183 hematologically healthy individuals (100 without DM, 83 with T2DM) were obtained. The association of HbA1c with a) hematologic parameters (hemoglobin, log[ferritin], RDW) and b) factors related to glycemia (BMI, fructosamine, FPG) was examined within each group separately and in the sum of the study sample.

RESULTS

There was a significant positive correlation of RDW with HbA1c among those without DM while the opposite was true among individuals with T2DM (r = 0.315, p = 0.001 and r = -0.275, p = 0.011). In the T2DM group a significant negative correlation with fructosamine was noted (r = -0.274, p = 0.012) which was absent among normoglycemic individuals. Among those without DM the association between HbA1c and RDW remained significant after adjustment for all tested parameters. In the population with T2DM the significance was attenuated after including glycemia-related factors values. In multivariable regression in the sum of the study sample, the interaction between diabetes status and RDW as regards HbA1c was significant [unstandardized correlation coefficient - 0.397 (-0.646 to -0.147), p = 0.002] and remained significant after adjustment for multiple potential confounders.

CONCLUSIONS

Among individuals without DM, the RDW likely reflects the non-glycemic interference on HbA1c values, while in T2DM RDW may serve as an indirect index of glycemia and dysmetabolism.

Factors associated with sclerostin levels - A calcification inhibitor - In individuals with type 2 diabetes mellitus; Is autonomic neuropathy the missing link?

BACKGROUND

Sclerostin inhibits bone formation and its expression is upregulated in the vasculature during the arterial calcification process as a counterregulatory mechanism preventing further calcification. Lower extremity arterial calcification (LEAC) is common in neuropathic patients with type 2 diabetes (T2DM). Herein, we investigated for associations between plasma sclerostin levels and diabetic neuropathy as well as LEAC in subjects with T2DM.

METHODS

A total of 74 individuals with and 76 without T2DMwere recruited. Plasma sclerostin levels were measured by ELISA. Diagnosis of cardiac autonomic neuropathy (CAN) was based on the battery of the four autonomic tests, while of somatosensory peripheral neuropathy (DPN) on neuropathy symptom score and neuropathy disability score. LEAC was assessed with conventional ankle and foot x-rays.

RESULTS

Plasma sclerostin levels were higher in participants with LEAC vs. those without LEAC in both diabetes and non-diabetes cohorts (p = 0.035 and p = 0.003, respectively). In the diabetes cohort, patients with CAN, but not with DPN, had higher sclerostin levels when compared with those without CAN (p < 0.001). Multivariate analysis in the diabetes cohort demonstrated that sclerostin levels were associated positively with CAN and LEAC, while in the non-diabetes cohort there was a trend for a positive association with male gender and presence of LEAC.

CONCLUSION

Plasma sclerostin levels are increased in individuals with LEAC irrespectively of diabetes status. In addition, plasma sclerostin concentrations are associated independently with LEAC and CAN in people with T2DM.

Pythagorean self-awareness intervention: A novel cognitive stress management technique for body weight control

BACKGROUND

Over the past decades, the prevalence of obesity has markedly increased worldwide. Stress is recognized as a substantial contributor to increased body weight; therefore, stress management interventions, especially cognitive behavioural, are becoming increasingly popular. The impact of stress management on stress- and obesity-related biomarkers (eg blood lipid profile, HBA1c, inflammatory biomarkers, such as CRP) has been scarcely studied. The aim of this study was to assess the effect of a novel cognitive behavioural stress management intervention, called 'Pythagorean Self-Awareness Intervention' (PSAI), in overweight/obese adults.

MATERIALS AND METHODS

This was a two-armed 1:1 randomized, nonblind controlled study including overweight/obese individuals. The control group followed a personalized Mediterranean low-calorie diet, and the intervention group followed the same diet in addition to the PSAI intervention for 8 weeks. Measurements included demographic, anthropometric (ie BMI, waist-to-hip ratio), stress (ie perceived stress, salivary cortisol), dietary behaviour (ie emotional eating) and metabolic parameters (ie blood lipid profile, HBA1c, CRP, body composition in fat and water). Outcome per-protocol analysis was performed using mixed linear models adjusted for age and gender.

RESULTS

A total of 49 of 62 eligible adults were analysed in the study (there were three dropouts in the intervention group and 10 dropouts in the control group); 28 were assigned to the intervention group (mean age 54.7 ± 11.9 years) and 21 to the control group (mean age 51.8 ± 11.9 years). The intervention group showed a statistically significant decrease in perceived stress, cortisol concentrations 30 minutes after awakening, cortisol's area under the curve, BMI, waist-to-hip ratio, restrained, emotional and external eating behaviour, fasting glucose, LDL, triglycerides, HbA1c and body and trunk fat, compared with the control group. Based on the observed effect sizes, clinically meaningful changes may be more evident in stress perception, restrained and external eating behaviour, Hb1ac and trunk fat. The compliance to the PSAI intervention reached 100%, and there were no adverse effects.

CONCLUSIONS

The PSAI technique may be an effective stress management method for overweight/obese adults. Future and larger randomized controlled studies are needed to allow generalization of these findings.