Low-grade inflammation in young adults exposed to intrauterine hyperglycemia

Circulating microRNAs associated with gestational diabetes mellitus: useful biomarkers?

Different types of small non-coding RNAs, especially miRNAs, may be found in the circulation, either protein-bound or enclosed in extracellular vesicles. During gestation, and particularly during gestational diabetes mellitus (GDM), the levels of several miRNAs are altered. Worldwide the incidence of GDM is increasing, in part driven by the current obesity epidemic. This is a point of public health concern because offspring of women with GDM frequently suffer from short- and long-term complications of maternal GDM. This has prompted the investigation of whether levels of specific miRNA species, detected early in gestation, may be used as diagnostic or prognostic markers for the development of GDM. Here, we summarize the mechanisms of RNA secretion and review circulating miRNAs associated with GDM. Several miRNAs are associated with GDM: miR-29a-3p and miR-29b-3p are generally upregulated in GDM pregnancies, also when measured prior to the development of GDM, while miR-16-5p is consistently upregulated in GDM pregnancies, especially in late gestation. miR-330-3p in circulation is increased in late gestation GDM women, especially in those with poor insulin secretion. miR-17-5p, miR-19a/b-3p, miR-223-3p, miR-155-5p, miR-125-a/b-5p, miR-210-3p and miR-132 are also associated with GDM, but less so and with more contradictory results reported. There could be a publication bias as miRNAs identified early are investigated the most, suggesting that it is likely that additional, more recently detected miRNAs could also be associated with GDM. Thus, circulating miRNAs show potential as biomarkers of GDM diagnosis or prognosis, especially multiple miRNAs containing prediction algorithms show promise, but further studies are needed.

Perinatal factors and high-sensitive C-reactive protein levels during adolescence

Objective

To examine whether perinatal factors are associated with low-grade inflammation measured by high-sensitivity C-reactive protein levels during adolescence.

Methods

Nested case-control study of 125 teenagers who were born by Cesarean delivery and had high-sensitivity C-reactive protein levels determined at 15–17 years. Data on obstetric and perinatal factors were recorded prospectively at the time of their birth.

Results

Median values of high-sensitivity C-reactive protein were significantly higher in teenagers, who were born as large for gestational age or with maternal diabetes compared to others (2.54 vs 0.34 mg/L; p < 0.024), and born during spring or summer compared to those born during winter or autumn (0.48 vs 0.27 mg/L; p < 0.023). No other perinatal associations were detected (for ex. such as electivity of operation, onset of labor, rupture of fetal membranes, cervical dilatation at delivery, gestational age, Apgar scores at 5 min, umbilical blood pH value, administration of neonatal antibiotics or need of neonatal intensive care treatment) in CRP levels. Further, teenagers with current body mass index in the highest tertile, regular medication for chronic disease and girls using oral contraceptives had significantly higher high-sensitivity C-reactive protein levels than others.

Conclusion

Prenatal exposures such as maternal metabolic environment and seasonality may have longterm effects on the low-grade inflammation and later cardiometabolic risks. Seasonality might be partly explained by maternal vitamin D levels during pregnancy, and thus future efforts are warranted to ensure sufficient vitamin D availability during pregnancy. Surprisingly, no other significant associations were detected between perinatal characteristics and high-sensitivity C-reactive protein levels.

Prepubertal Children Exposed to Maternal Gestational Diabetes Have Latent Low-Grade Inflammation

BACKGROUND

Maternal gestational diabetes mellitus (GDM) and overweight are associated with an increased risk of obesity and the metabolic syndrome in the adult offspring. We studied the influence of maternal GDM on prepubertal children's height, weight, body mass index (BMI), lipid and glucose metabolism, and low-grade inflammation.

METHODS

A cohort of 135 prepubertal Caucasian children (age range 4.4-9.7 years) was studied in a controlled cross-sectional study. Seventy-seven children had been exposed to maternal GDM, and 58 children born after a normal pregnancy served as controls. The outcomes were height, weight, BMI, blood pressure, and biochemical markers of glucose and lipid metabolism and inflammation.

RESULTS

There were no differences in height, weight, BMI, fasting serum insulin, plasma glucose, lipids, or blood pressure between the study groups. However, high-sensitivity C-reactive protein (hs-CRP) was significantly higher in the GDM group than in the controls (p = 0.001).

CONCLUSIONS

Higher hs-CRP as a marker of low-grade inflammation was detected in prepubertal children exposed to maternal GDM, but no differences were seen in height, weight, BMI, or markers of glucose and lipid metabolism compared to control children. This finding may reflect an ongoing process of metabolic changes in children born after a GDM pregnancy.

Consequences of gestational diabetes to the brain and behavior of the offspring

Gestational diabetes mellitus (GD) is a form of insulin resistance triggered during the second/third trimesters of pregnancy in previously normoglycemic women. It is currently estimated that 10% of all pregnancies in the United States show this condition. For many years, the transient nature of GD has led researchers and physicians to assume that long-term consequences were absent. However, GD diagnosis leads to a six-fold increase in the risk of developing type 2 diabetes (T2D) in women and incidence of obesity and T2D is also higher among their infants. Recent and concerning evidences point to detrimental effects of GD on the behavior and cognition of the offspring, which often persist until adolescence or adulthood. Considering that the perinatal period is critical for determination of adult behavior, it is expected that the intra-uterine exposure to hyperglycemia, hyperinsulinemia and pro-inflammatory mediators, hallmark features of GD, might affect brain development. Here, we review early clinical and experimental evidence linking GD to consequences on the behavior of the offspring, focusing on memory and mood disorders. We also discuss initial evidence suggesting that downregulation of insulin signaling cascades are seen in the brains of GD offspring and could contribute to the consequences on their behavior.

Gene Expression and DNA Methylation of PPARGC1A in Muscle and Adipose Tissue From Adult Offspring of Women With Diabetes in Pregnancy

Prenatal exposure to maternal hyperglycemia is associated with an increased risk of later adverse metabolic health. Changes in the regulation of peroxisome proliferator-activated receptor-γ coactivator-1α (PPARGC1A) in skeletal muscle and subcutaneous adipose tissue (SAT) is suggested to play a role in the developmental programming of dysmetabolism based on studies of human subjects exposed to an abnormal intrauterine environment (e.g., individuals with a low birth weight). We studied 206 adult offspring of women with gestational diabetes mellitus (O-GDM) or type 1 diabetes (O-T1D) and of women from the background population (O-BP) using a clinical examination, oral glucose tolerance test, and gene expression and DNA methylation of PPARGC1A in skeletal muscle and SAT. Plasma glucose was significantly higher for both O-GDM and O-T1D compared with O-BP (P < 0.05). PPARGC1A gene expression in muscle was lower in O-GDM compared with O-BP (P = 0.0003), whereas no differences were found between O-T1D and O-BP in either tissue. PPARGC1A DNA methylation percentages in muscle and SAT were similar among all groups. Decreased PPARGC1A gene expression in muscle has previously been associated with abnormal insulin function and may thus contribute to the increased risk of metabolic disease in O-GDM. The unaltered PPARGC1A gene expression in muscle of O-T1D suggests that factors other than intrauterine hyperglycemia may contribute to the decreased PPARGC1A expression in O-GDM.

Gestational diabetes mellitus and long-term consequences for mother and offspring: a view from Denmark

Gestational diabetes mellitus (GDM) is defined as glucose intolerance of varying severity and is present in about 2-6% of all pregnancies in Europe, making it one of the most common pregnancy disorders. Aside from the short-term maternal, fetal and neonatal consequences associated with GDM, there are long-term consequences for both mother and child. Although maternal glucose tolerance often normalises shortly after pregnancy, women with GDM have a substantially increased risk of developing type 2 diabetes later in life. Studies have reported that women are more than seven times as likely to develop diabetes after GDM, and that approximately 50% of mothers with GDM will develop diabetes within 10 years, making GDM one of the strongest predictors of type 2 diabetes. In women with previous GDM, development of type 2 diabetes can be prevented or delayed by lifestyle intervention and/or medical treatment. Systematic follow-up programmes would be ideal to prevent progression of GDM to diabetes, but such programmes are unfortunately lacking in the routine clinical set-up in most countries. Studies have found that the risks of obesity, the metabolic syndrome, type 2 diabetes and impaired insulin sensitivity and secretion in offspring of mothers with GDM are two- to eightfold those in offspring of mothers without GDM. The underlying pathogenic mechanisms behind the abnormal metabolic risk profile in offspring are unknown, but epigenetic changes induced by exposure to maternal hyperglycaemia during fetal life are implicated. Animal studies indicate that treatment can prevent long-term metabolic complications in offspring, but this remains to be confirmed in humans. Thus, diabetes begets diabetes and it is likely that GDM plays a significant role in the global diabetes epidemic. This review summarises a presentation given at the 'Gestational diabetes: what's up?' symposium at the 2015 annual meeting of the EASD. It is accompanied by two other reviews on topics from this symposium (by Marja Vääräsmäki, DOI: 10.1007/s00125-016-3976-6 , and by Cuilin Zhang and colleagues, DOI: 10.1007/s00125-016-3979-3 ) and an overview by the Session Chair, Kerstin Berntorp (DOI: 10.1007/s00125-016-3975-7 ).

Levels of the inflammation marker YKL-40 in young adults exposed to intrauterine hyperglycemia

Plasma levels of the inflammatory marker YKL-40 were investigated in 597 adult offspring born to women with and without diabetes during pregnancy. No association between fetal exposure to maternal hyperglycemia and levels of YKL-40 was found. However, female sex and increasing BMI in the offspring were associated to YKL-40.