Studies suggest that placental nutrient supply adapts according to fetal demands. However, signaling events underlying placental adaptations remain unknown. Here we demonstrate that phosphoinositide 3-kinase p110α in the fetus and the trophoblast interplay to regulate placental nutrient supply and fetal growth. Complete loss of fetal p110α caused embryonic death, whilst heterozygous loss resulted in fetal growth restriction and impaired placental formation and nutrient transport. Loss of trophoblast p110α resulted in viable fetuses, abnormal placental development and a failure of the placenta to transport sufficient nutrients to match fetal demands for growth. Using RNA-seq we identified genes downstream of p110α in the trophoblast that are important in adapting placental phenotype. Using CRISPR/Cas9 we showed loss of p110α differentially affects gene expression in trophoblast and embryonic stem cells. Our findings reveal important, but distinct roles for p110α in the different compartments of the conceptus, which control fetal resource acquisition and growth.
To understand the relationship between birth weight and altitude to improve health outcomes in high-altitude populations, to systematically assess the impact of
Accepted ArticleThis article is protected by copyright. All rights reserved altitude on the likelihood of low birth weight (LBW), small for gestational age (SGA), and spontaneous preterm birth (sPTB), and to estimate the magnitude of reduced birth weight associated with altitude.Methods: PubMed, OvidEMBASE, Cochrane Library, Medline, Web of Science, and clinicaltrials.gov were searched (from inception to November 11, 2020). Observational, cohort, or case-control studies were included if they reported a high altitude (>2500 m) and appropriate control population.Results: Of 2524 studies identified, 59 were included (n=1 604 770 pregnancies). Data were abstracted according to PRISMA guidelines, and were pooled using random-effects models. There are greater odds of LBW (odds ratio [OR] 1.47, 95% confidence interval [
Introduction: Metformin is among the most frequently prescribed drugs worldwide for a variety of indications. Although metformin has several important advantages, for example being easy to store and administer, it is associated with a high incidence of gastrointestinal side effects. Slower-release formulations of metformin may reduce the incidence of side effects while maintaining efficacy; however, there is a lack of systematic evidence available to guide head-to-head comparisons between different metformin formulations.Methods: PubMed, Web of Science, OVID EMBASE, MEDLINE, The Cochrane database and Clinicaltrials.gov were systematically searched (from inception to 25 January 2021). Trials that randomized adult participants to extendedrelease formulation of metformin (met-XR), delayed-release (met-DR) or immediate-release metformin (met-IR) were included. Two reviewers independently assessed articles for eligibility and risk-of-bias, with conflicts resolved by a third reviewer. Outcome measures were change in fasting plasma glucose (FPG), glycated haemoglobin (HbA1c), body weight, BMI, lipid profile and side effects. Meta-analyses were conducted using random-effects models. Results: Fifteen studies (n = 3765) met eligibility criteria. There was no significant difference between the efficacy of met-IR, met-XR or met-DR in changing FPG (p = 0.93). A non-significant reduction in mean body weight was observed in individuals randomized to met-XR vs. met-IR (-1.03 kg, 95% CI -2.12 to 0.05, p = 0.06). Individuals randomized to met-XR vs. met-IR had lower low-density lipoprotein (LDL) cholesterol levels (-5.73 mg/dl, 95% CI -7.91 to -3.56, p \ 0.00001). Gastrointestinal (GI) side effects were markedly reduced in patients randomised to met-DR vs. met-IR (OR 0.45, 95% CI 0.26-0.80, p = 0.006).
Conclusion:Our results demonstrate equal efficacy of longer-acting formulations (met-XR, met-DR) versus immediate-release metformin formulations in terms of glycaemic control.
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