Ageing influences the relationship of circulating miR-33a and miR- 33b levels with insulin resistance and adiposity

OBJECTIVE

The identification of circulating microRNAs related to abnormal metabolic function may be useful in the context of ageing, adiposity and insulin resistance. The miR-33 a/b has been shown to control the expression of genes involved in fatty acid biosynthesis, impaired metabolism and insulin resistance. In this study, we aimed to identify differences in circulating miR-33 a/b levels according to age-related metabolic impairment and increased adiposity.

METHODS

This study included 80 individuals (30.2% with obesity, 70% females) classified according to insulin resistance (Stern's criteria) and age [young (20-39 years) and senior (40-59 years)]. Body fat was evaluated using bioelectrical impedance, biochemical markers by colorimetric, enzymatic and immuno-turbidimetry methods. TaqMan measures of circulating miR-33 a and miR-33 b with quantitative reverse transcription polymerase chain reaction in serum were assessed in association with clinical outputs.

RESULTS

Circulating miR-33 a and miR-33 b levels showed significant association with fatness, the lipid profile and biomarkers of impaired glucose metabolism. Both miR-33 a and miR-33 b were associated with visceral adiposity index in non-insulin resistance and insulin resistance individuals. More important, for miR-33 a circulating levels in senior group, receiver operating characteristic curve analyses showed area under the curve 0.804 ( p = 0.010; 95% confidence interval = 0.655-0.952).

CONCLUSION

Ageing influenced the relationship of circulating miR-33 a and miR-33 b with insulin resistance and increased adiposity.

[Adiposity percentage relationship with hormone receptors immunoreactive score in breast cancer mexican women]

INTRODUCTION

Adipose tissue is an important estrogen resource and they are involved in breast cancer development.

OBJECTIVE

To establish the relationship between adiposity percentage and the estrogen and progesterone receptors immunoreactive score in Mexican women with breast cancer.

METHODS

This is a transversal and analytical study. We identified breast cancer women with cancer histologic diagnosis. We calculated: adiposity percentage and immunoreactive score. We performed correlation analysis between adiposity percentage, body mass index, diabetes mellitus and arterial hypertension, with estrogen and progesterone receptors in breast cancer samples. We perform logistic regression and Odds Ratio estimations.

RESULTS

We studied 43 patients with breast cancer and we observed association between adiposity percentage and estrogen and progesterone immnunoreactive score (rP 0.470; p 0.003 and rP 0.328; p 0.042, respectively). The most important risk factor in breast cancer positive to estrogen receptors was obesity (OR 19.1, IC95% 2.1 a 169.1, p 0.008), and previous obesity in breast cancer positive to progesterone receptors (OR 20.7, IC95% 2.3 a 185.9, p 0.007).

DISCUSSION

Adiposity percentage is an important risk factor to develop breast cancer positive to hormone receptors related with the risk of breast cancer positive to hormonal receptors.

Association of CD28 IVS3 +17T/C polymorphism with soluble CD28 in rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology in which inflammatory pathology involves T cell activation and the CD28 costimulatory molecule involved in T cell presentation. The gene includes the CD28 IVS3 +17T/C polymorphism that could be associated with susceptibility to RA whereas the soluble concentrations of CD28 (sCD28) could be related to clinical activity.

METHODS

We investigated the CD28 IVS3 +17T/C polymorphism in 200 RA patients and 200 healthy subjects (HS). Furthermore, we quantified the sCD28 concentrations in 77 samples of each group. We applied indexes focused to determine the activity and disability (DAS28 and Spanish HAQ-DI, respectively) in RA patients.

RESULTS

RA patients had significantly higher frequencies of the CD28 T allele compared to HS (p = 0.032 OR = 1.59, C.I. 1.02-2.49). In addition, the IVS3 +17 T/T genotype frequency was also increased in RA vs. HS (p = 0.026). The RA patients showed higher sCD28 serum levels than HS (p = 0.001). Carriers of the T/T genotype in RA patients showed higher sCD28 levels than C/C carriers (p =0.047). In addition, a correlation between sCD28 and Spanish HAQ-DI (correlation, 0.272; p =0.016), was found.

CONCLUSION

The T allele in CD28 IVS3 +17T/C polymorphism is associated with a susceptibility to RA in Western Mexico. In addition, increased sCD28 levels are related to T/T genotype in RA patients.