Cocientes lipoproteicos: significado fisiológico y utilidad clínica de los índices aterogénicos en prevención cardiovascular

Metabolic Biomarkers in Adults with Type 2 Diabetes: The Role of PPAR-γ2 and PPAR-β/δ Polymorphisms

Glucose and lipid metabolism regulation by the peroxisome proliferator-activated receptors (PPARs) has been extensively reported. However, the role of their polymorphisms remains unclear.

OBJECTIVE

To determine the relation between PPAR-γ2 rs1801282 (Pro12Ala) and PPAR-β/δ rs2016520 (+294T/C) polymorphisms and metabolic biomarkers in adults with type 2 diabetes (T2D).

MATERIALS AND METHODS

We included 314 patients with T2D. Information on anthropometric, fasting plasma glucose (FPG), HbA1c and lipid profile measurements was taken from clinical records. Genomic DNA was obtained from peripheral blood. End-point PCR was used for PPAR-γ2 rs1801282, while for PPAR-β/δ rs2016520 the PCR product was digested with Bsl-I enzyme. Data were compared with parametric or non-parametric tests. Multivariate models were used to adjust for covariates and interaction effects.

RESULTS

minor allele frequency was 12.42% for PPAR-γ2 rs1801282-G and 13.85% for PPAR-β/δ rs2016520-C. Both polymorphisms were related to waist circumference; they showed independent effects on HbA1c, while they interacted for FPG; carriers of both PPAR minor alleles had the highest values. Interactions between FPG and polymorphisms were identified in their relation to triglyceride level.

CONCLUSIONS

PPAR-γ2 rs1801282 and PPAR-β/δ rs2016520 polymorphisms are associated with anthropometric, glucose, and lipid metabolism biomarkers in T2D patients. Further research is required on the molecular mechanisms involved.

Atherogenic indices in pediatric population in South-Southeast region of Mexico

BACKGROUND

Atherosclerosis is a cardiovascular disease, highly predictable, and associated with different atherogenic indices (AI) in adults. However, such indexes in the pediatric population are far less explored. The objective of this study was to evaluate the AI and the cardiovascular factors in the pediatric population in the South-Southeast of México.

METHODS

A total of 481 children between 2 and 17 years old were recruited. Anthropometric evaluation, blood pressure (BP), lipid profile, apolipoprotein A-I (ApoA-I) and apolipoprotein B (ApoB) were measured, and AI were calculated. The population was grouped by age, binary logistic regression analysis was performed to analysis for associations of AI and cardiovascular risk factors. Sensibility and specificity of AI to detect metabolic alteration were evaluated for curve ROC.

RESULTS

The atherogenic risk presented a high prevalence in the pediatric population, such as LDL-c/ApoB (86.9%), AIP (78%) and AC (36.6%). Preschoolers showed a higher risk of ApoB/ApoA-I and ApoB/LDL-c, while adolescents have a high risk of AIP. CRI-I and AC were associated with elements of lipid profile and body mass index (BMI). ROC curves analysis shows that AIP is the best index evaluating metabolic syndrome (MS) (0.87) and dyslipidemia (0.91).

CONCLUSION

Such pediatric population showed a high risk of AI, mainly by LDL-c/ApoB and AIP. The BMI was the cardiovascular risk factors most frequently related to AI, AIP is the best index for detecting cases of MS and dyslipidemia. This is the first study carried out in the pediatric population from the South-Southeast of Mexico that evaluated the AI.

Catalase post-translational modifications as key targets in the control of erythrocyte redox homeostasis in children with obesity and insulin resistance

Insulin resistance (IR) is the most common metabolic disturbance in children with obesity. Children with obesity and insulin resistance (ObIR+) display a detriment in erythroid antioxidant defenses, caused by an impaired catalase activity and the increase in oxidative and pro-inflammatory markers. Therefore, erythrocytes from ObRI+ are more vulnerable to any oxidative stress elicitor. Since catalase is one of the erythrocytes' first antioxidant defenses, we intended to delve into the mechanisms underlying catalase's impaired activity. Given the lack of cellular organelles in erythrocytes, which prevents protein synthesis, we aimed study catalase post-translational modifications (PTMs) as targets of pro-inflammatory and pro-oxidant status of these cells in children with obesity and IR. Catalase levels of O-glycosylation, tyrosine nitration and S-glutathionylation were analyzed by Western blotting (WB) using immunoprecipitated catalase (IP-CAT) from erythrocyte lysates. Furthermore, Catalase was also identified by LC-MS/MS after isolation and enrichment of erythrocyte nitrosated proteins with a biotin switch approach. The results obtained suggest that catalase inhibition seen in children with obesity is partly due to the increase in the S-nitrosation of the enzyme. Indeed, exogenous administration of nitric oxide (NO) to cultured erythrocytes resulted in a decrease in catalase activity in all groups. Signals of other PTMs (O-glycosylation, Tyr-nitration and S-glutathionylation) were also detected in the erythrocyte catalase in every groups, although levels of catalase O-glycosylation and S-glutathionylation decreased in ObIR+. No evidence of differences in Tyr-nitration of catalase levels were found among groups. The study again highlights the role of erythrocytes as sensors of the inflammatory and pro-oxidant response to which these cells are subjected in children with obesity and insulin resistance.

Improvement of serum lipid parameters in consumers of Mexican Wagyu-Cross beef: A randomized controlled trial

Beef is considered an excellent source of high-quality protein and micronutrients. The high saturated fatty acid (SFA) composition of beef has been associated with cardiovascular diseases; however, this is a controversial issue because at present, no evidence has scientifically proven such an association. Wagyu cattle have been used as an option to generate high-quality fatty acids (FAs) in beef and have been crossed with local beef cattle (Wagyu-Cross). In Mexico, Wagyu-Cross is marketed assuming the same quality as purebred Wagyu meat without scientific support. This study aimed to determine whether the differences in the FA composition of Wagyu-Cross and commercial beef affected lipid metabolism in frequent consumers of beef. The study is a randomized, controlled, double-blinded phase IV clinical trial. Thirty-four volunteers completed treatments in which 120 g ground beef was consumed 3 days per week for 2 weeks. Volunteers were randomized to the "A" (commercial meat) or "B" (Wagyu-Cross meat) groups. The beef fat content was 87% higher, the SFA content was 2.3% lower, and the monounsaturated fatty acid (MUFA) C18:1 n-9 concentrations were higher in Wagyu-Cross beef than in commercial beef. The B group exhibited a significantly larger change from baseline in the serum lipid profile in total cholesterol (TC) (-4.7% versus +6.9%), low-density lipoprotein (LDL) (-4.1% versus +10.0%), nonhigh-density lipoprotein (non-HDL) (-6.1% versus +4.9%), and the ratio of three atherogenic indexes-TC/HDL (-3.5% versus +6.4%), LDL/HDL (-2.8% versus +14.6%), and non-HDL/HDL (-4.7% versus +9.3%)-than the A group. This result confirms that meat FA composition is a key point for redirecting cattle breeding strategies and promotes beef as a healthful protein source. PRACTICAL APPLICATION: Here, we found new evidence based on a clinical trial that beef with a favorable fatty acid composition (i.e., monounsaturated fatty acid and polyunsaturated fatty acid content) is a key factor in improving parameters associated with consumer health. This information will support the design of cattle breeding strategies as an option to promote beef consumption as a healthier protein source and create opportunities for the development of the functional food industry.

[Relationship between nutritional status and triglyceride/c-hdl index in adolescents treated in a public hospital]

Objective

To determine the relationship between nutritional status according to body mass index (BMI) and triglyceride index/c-HDL in adolescents treated in a public hospital.

Materials and methods

Observational, transversal, and retrospective study of the nutritional education database program of Hospital I - Rioja - EsSalud, from March 2017 to June 2018. The nutritional status was determined according to the body mass index for age (BMI/age) and the index of Tg/c-HDL as the ratio between triglycerides and HDL cholesterol.

Results

The study was made up of 130 adolescents (70 females and 60 males) between 10 - 18 years old, who were treated in the nutrition service of Hospital I - Rioja- EsSalud. The average age of the adolescents was 12.6 ± 2.2 years. The average Tg/c-HDL index was 2.41 ± 0.48; it was higher in males (2.46 ± 0.51) than in females (2.37 ± 0.44); likewise, obesity (2.70 ± 0.49), overweight (2.46 ± 0.41) and the risk of underweight (2.36 ± 0.55) were the nutritional states that presented the highest Tg/c-HDL index. A positive and significant correlation (r=0.447, p=0.000) was found between BMI and Tg/c-HDL index.

Conclusions

There was a positive and statistically significant relationship between the body mass index and the Tg / HDL-c index in this adolescent population. The Tg / HDL-c index was higher in the nutritional status of obesity and overweight, exceeding the value of the media population.

Pro12Ala PPAR-γ2 and +294T/C PPAR-δ Polymorphisms and Association with Metabolic Traits in Teenagers from Northern Mexico

Peroxisome proliferator-activated receptors (PPARs) play roles in glucose and lipid metabolism regulation. Pro12Ala PPAR-γ2 and +294T/C PPAR-δ have been associated with dyslipidemia, hyperglycemia and high body mass index (BMI). We compared metabolic traits and determined associations with Pro12Ala PPAR-γ2 or +294T/C PPAR-δ polymorphism among teenagers from different ethnicity. Four hundred and twelve samples with previous biochemical and biometric measurements were used. Genomic DNA from peripheral blood was extracted and analyzed by end-point PCR for Pro12Ala PPAR-γ2. The +294T/C PPAR-δ PCR product was also digested with Bsl I. Two genotype groups were formed: major allele homozygous and minor allele carriers. Pro12Ala PPAR-γ2 G minor allele frequencies were: 10% in Mestizo-1, 19% in Mestizo-2, 23% in Tarahumara, 12% in Mennonite, and 17% in the total studied population. The +294T/C PPAR-δ C minor allele frequencies were: 18% in Mestizo-1, 20% in Mestizo-2, 6% in Tarahumara, 13% in Mennonite, and 12% in the total studied population. Teenagers with PPAR-γ2 G allele showed a greater risk for either high waist/height ratio or low high-density lipoprotein; and, also had lower total cholesterol. Whereas, PPAR-γ2 G allele showed lower overweight/obesity phenotype (BMI Z-score) frequency, PPAR-δ C allele was a risk factor for it. Metabolic traits were associated with both PPAR polymorphisms.