Insulin increases placental triglyceride as a potential mechanism for fetal adiposity in maternal obesity

Maternal Obesity Alters Placental and Umbilical Cord Plasma Oxidative Stress, a Cross-Sectional Study

Maternal obesity has been shown to impair the oxidative status in the placenta and newborns, potentially leading to adverse pregnancy outcomes and long-term effects on the programming of offspring metabolic status. This study aimed to investigate the impact of maternal obesity on maternal and umbilical cord plasma oxidative status, as well as placental oxidative adaptation. Maternal obesity (n = 20), defined as a pre-pregnancy BMI ≥ 25 kg/m2, and maternal leanness (n = 20), defined as a pre-pregnancy BMI < 23 kg/m2, were the group categories used in this study. Both groups were matched according to gestational age at delivery. Maternal blood, umbilical cord blood, and placental tissue were collected to assess nutritional content (cholesterol, triglyceride, and protein), oxidative stress markers (MDA and protein carbonyl), and antioxidant activity (SOD and catalase). Placental protein expression (SOD2, catalase, UCP2, and Nrf2) was evaluated using Western blot analysis. Catalase activity in maternal plasma significantly increased in the maternal obesity group (p = 0.0200), with a trend toward increased MDA and protein carbonyl levels. In umbilical cord plasma, triglyceride, protein carbonyl, and catalase activity were significantly elevated in the maternal obesity group compared with the lean controls (p = 0.0482, 0.0291, and 0.0347, respectively). Placental protein expression analysis revealed significantly decreased SOD2 (p = 0.0011) and catalase (p < 0.0001), along with Nrf2 downregulation (p < 0.0001). An increase in mitochondrial antioxidant UCP2 expression was observed (p = 0.0117). The neonatal protein carbonyl levels positively correlated with placental protein carbonyl (r = 0.7405, p < 0.0001) and negatively correlated with maternal catalase activity (r = -0.4332, p = 0.0052). This study thus provides evidence that maternal obesity is associated with placental and fetal oxidative stress, alongside a concurrent increase in placental antioxidant UCP2 expression.

IGF-1 and IGF-2 as Molecules Linked to Causes and Consequences of Obesity from Fetal Life to Adulthood: A Systematic Review

This study examines the impact of insulin-like growth factor 1 (IGF-1) and insulin-like growth factor 2 (IGF-2) on various aspects of children's health-from the realms of growth and puberty to the nuanced characteristics of metabolic syndrome, diabetes, liver pathology, carcinogenic potential, and cardiovascular disorders. A comprehensive literature review was conducted using PubMed, with a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method employing specific keywords related to child health, obesity, and insulin-like growth factors. This study reveals associations between insulin-like growth factor 1 and birth weight, early growth, and adiposity. Moreover, insulin-like growth factors play a pivotal role in regulating bone development and height during childhood, with potential implications for puberty onset. This research uncovers insulin-like growth factor 1 and insulin-like growth factor 2 as potential biomarkers and therapeutic targets for metabolic dysfunction-associated liver disease and hepatocellular carcinoma, and it also highlights the association between insulin-like growth factors (IGFs) and cancer. Additionally, this research explores the impact of insulin-like growth factors on cardiovascular health, noting their role in cardiomyocyte hypertrophy. Insulin-like growth factors play vital roles in human physiology, influencing growth and development from fetal stages to adulthood. The impact of maternal obesity on children's IGF levels is complex, influencing growth and carrying potential metabolic consequences. Imbalances in IGF levels are linked to a range of health conditions (e.g., insulin resistance, glucose intolerance, metabolic syndrome, and diabetes), prompting researchers to seek novel therapies and preventive strategies, offering challenges and opportunities in healthcare.

Physical activity, gestational weight gain in obese patients with early gestational diabetes and the perinatal outcome - a randomised-controlled trial

BACKGROUND

Excessive gestational weight gain, especially among women with gestational diabetes, is associated with several adverse perinatal outcomes. Our study aimed to analyse the impact of the use of pedometers to supervise physical activity on maternal health and the obstetric outcomes of pregnant women with obesity and early gestational diabetes.

METHODS

124 pregnant patients were enrolled in the presented research.

INCLUSION CRITERIA

singleton pregnancy, age > 18 years, gestational diabetes diagnosed in the first half of pregnancy (< 20th week of pregnancy), obesity according to the American Endocrine Society criteria. Each patient was advised to take at least 5000 steps daily. Patients were randomly assigned to pedometers (N = 62), and were recommended to monitor daily the number of steps. The group without pedometers (N = 62) was not observed. Visit (V1) was scheduled between the 28th and 32nd gestational week (GW), and visit (V2) occurred between the 37th and 39th GW. Anthropometric measurements and blood samples were collected from all patients at each appointment. Foetal and maternal outcomes were analysed at the end of the study.

RESULTS

In the group supervised by pedometers, there were significantly fewer newborns with macrosomia (p = 0,03). Only 45% of patients satisfied the recommended physical activity guidelines. Patients who walked more than 5000 steps per day had significantly higher body weight at baseline (p = 0,005), but weight gain was significantly lower than in the group that did not exceed 5000 steps per day (p < 0,001). The perinatal outcome in the group of patients performing more than 5000 steps did not demonstrate significant differences with when compared to less active group. ROC curve for weight gain above the guidelines indicated a statistically substantial cut-off point for this group at the level of 4210 steps/day (p = 0.00001).

CONCLUSIONS

Monitoring the activity of pregnant patients with gestational diabetes and obesity by pedometers did not have a significantly impact on their metabolic control and weight gain. However, it contributed to less macrosomia. Furthermore, physical activity over 5,000 steps per day positively affects weight loss, as well as contributes to improved obstetric and neonatal outcomes.

RISING STARS: Mechanistic insights into maternal-fetal cross talk and islet beta-cell development

The metabolic health trajectory of an individual is shaped as early as prepregnancy, during pregnancy, and lactation period. Both maternal nutrition and metabolic health status are critical factors in the programming of offspring toward an increased propensity to developing type 2 diabetes in adulthood. Pancreatic beta-cells, part of the endocrine islets, which are nutrient-sensitive tissues important for glucose metabolism, are primed early in life (the first 1000 days in humans) with limited plasticity later in life. This suggests the high importance of the developmental window of programming in utero and early in life. This review will focus on how changes to the maternal milieu increase offspring's susceptibility to diabetes through changes in pancreatic beta-cell mass and function and discuss potential mechanisms by which placental-driven nutrient availability, hormones, exosomes, and immune alterations that may impact beta-cell development in utero, thereby affecting susceptibility to type 2 diabetes in adulthood.

Effects of a High-Fat Diet and Docosahexaenoic Acid during Pregnancy on Fatty Acid Composition in the Fetal Livers of Mice

A high-fat diet (HFD) during pregnancy promotes fat accumulation and reduces docosahexaenoic acid (DHA) levels in the liver of the offspring at postnatal ages, which can depend on fetal sex. However, the prenatal mechanisms behind these associations are still unclear. Thus, we analyzed if an HFD alters DHA content and the expression of molecules related to fatty acid (FA) metabolism in the fetal liver. Female C57BL/6 mice were fed a control diet or HFD for 4-6 weeks before pregnancy until the gestational day (GD) 17.5. A subgroup of each diet received DHA (100 mg/Kg) orally from GD 6.5 until 16.5. On GD 17.5, maternal livers, placentas, and livers from male and female fetuses were collected for FA profiling with gas-chromatography and gene expression of molecules related to FA metabolism using qPCR. PPAR-α protein expression was evaluated using Western blot. The gene expression of placental FA transporters was also assessed. An HFD increased eicosapentaenoic acid (EPA) and decreased DHA levels and protein expression of PPAR-α in the fetal livers of both sexes. DHA increased the gene expression of Ppara, Cpt1, and Acsl1 in the livers of female fetuses. Therefore, an HFD reduces DHA levels and PPAR-α, a master regulator of gene expression, in the fetal liver. In turn, the livers of female fetuses seem to be more sensitive to DHA action.

Myo-inositol alters the effects of glucose, leptin and insulin on placental palmitic acid and oleic acid metabolism

Well-regulated placental palmitic acid (PA) and oleic acid (OA) metabolism is vital for optimal placental function and fetal development, but dysregulation occurs with gestational diabetes (GDM). We hypothesized that such dysregulation might arise from increased maternofetal glucose, leptin or insulin concentrations present in GDM, and that dysregulated PA and OA lipid metabolism could be moderated by myo-inositol, a natural polyol and potential GDM intervention. Placental explants from 21 women were incubated with stable isotope-labelled 13 C-PA or 13 C-OA for 48 h. Explants were treated with glucose (5, 10 mm) or leptin (13 nm) or insulin (150 nm) in combination with myo-inositol (0.3, 30, 60 μm). Forty-seven 13 C-PA lipids and 37 13 C-OA lipids were measured by liquid chromatography-mass spectrometry (LCMS). Compared with controls (5 mm glucose), glucose (10 mm) increased 19 13 C-OA lipids and nine 13 C-PA lipids, but decreased 13 C-OA phosphatidylethanolamine 38:5 and 13 C-PA phosphatidylethanolamine 36:4. The effects of leptin and insulin were less prominent than glucose, with leptin increasing 13 C-OA acylcarnitine 18:1, and insulin increasing four 13 C-PA triacylglycerides. Most glucose, leptin and insulin-induced alterations in lipids were attenuated by co-incubation with myo-inositol (30 or 60 μm), with attenuation also occurring in all subgroups stratified by GDM status and fetal sex. However, glucose-induced increases in acylcarnitine were not attenuated by myo-inositol and were even exaggerated in some instances. Myo-inositol therefore appears to generally act as a moderator, suppressing the perturbation of lipid metabolic processes by glucose, leptin and insulin in placenta in vitro. Whether myo-inositol protects the fetus and pregnancy from unfavourable outcomes requires further research. KEY POINTS: Incubation of placental explants with additional glucose, or to a lesser extent insulin or leptin, alters the placental production of 13 C-lipids from 13 C-palmitic acid (PA) and 13 C-oleic acid (OA) in vitro compared with untreated controls from the same placenta. Co-incubation with myo-inositol attenuated most alterations induced by glucose, insulin or leptin in 13 C-lipids, but did not affect alterations in 13 C-acylcarnitines. Alterations induced by glucose and leptin in 13 C-PA triacylglycerides and 13 C-PA phospholipids were influenced by fetal sex and gestational diabetes status, but were all still attenuated by myo-inositol co-incubation. Insulin differently affected 13 C-PA triacylglycerides and 13 C-PA phospholipids depending on fetal sex, with alterations also attenuated by myo-inositol co-incubation.