Implicações da diabetes gestacional sobre os parâmetros imunológicos e bioquímicos do colostro e do sangue materno

Abstract

In addition to nutrients, breast milk provides protection against respiratory infections, diarrhea, allergies and deficiency diseases. Despite all the knowledge on the subject, little is known about its immunological and biochemical composition specifically in diabetic mothers. The aim of the study was to evaluate the composition of colostrum and blood of diabetic mothers, and, due to the pandemic caused by the SARS-Cov-2 virus, we carried out a systematic review to study the immunological aspects of the colostrum of puerperal women during the COVID-19 pandemic. For the first objective, we evaluated in the colostrum and blood of 36 mothers with gestational diabetes and 36 non-diabetic mothers, hospitalized in the Joint Accommodation of the University Hospital of the Federal University of Maranhão - UFMA, Maternal and Child Unit, the following parameters: concentration of total IgA antibodies and anti-insulin IgA, by immunoenzymatic assay (ELISA); concentration of cytokines IL-10, TNF-α, INF-γ, TGF-β by the microsphere technique (Cytometric Bead Array - CBA) and the concentration of calcium, glucose, total cholesterol, triglycerides, total proteins by colorimetric assay. Student t test was used to compare average concentrations between the two groups. Pearson's correlation coefficient was used to explore the correlations between the concentrations of antibodies and cytokines and independent variables. For all tests, a level of statistical significance of p p < 0,05 was adopted. Statistical analysis was performed using the GraphPad Prism 7.0 program. We found that the concentration of IgA anti-insulin antibody was always higher in the blood and colostrum of diabetic mothers, when compared to non-diabetic mothers (p <0.001). It was also observed that the use of exogenous insulin during the treatment of diabetes did not interfere in any of the parameters among mothers with gestational diabetes. The evaluation of the cytokine concentrations of diabetic mothers showed a significant increase in TGF-β in serum (p = 0.030) and TNF-α in colostrum (p = 0.007) compared to normoglycemic ones, in the biochemical evaluation, the serum glucose concentration was significantly higher in mothers with gestational diabetes mellitus (p = 0.03). As for the second objective, a systematic review was carried out based on the following guiding question: does maternal hyperglycemia associated or not with COVID-19 influence the immunological composition of colostrum? The following databases were used: MEDLINE / PUBMED, LILACS, SCOPUS and Google Scholar. Seven studies were found, six of which were cross-sectional and one case report. The studies found pointed out that there is a lower concentration of anti-IgA antibodies both in colostrum and in the serum of diabetic mothers, and the evidence points to the presence of anti-SARS-CoV-2 antibodies in breast milk in women who had been infected by the virus during pregnancy. We conclude that gestational diabetes can influence the concentration of anti-insulin antibodies and cytokines in colostrum and maternal serum, and the evidence, after a systematic review on the subject, points to the presence of anti-SARS-CoV-2 antibodies in breast milk in women who had the virus infection during pregnancy.