The miR‐379/miR‐410 cluster at the imprinted Dlk1‐Dio3 domain controls neonatal metabolic adaptation

In mammals, birth entails complex metabolic adjustments essential for neonatal survival. Using a mouse knockout model, we identify crucial biological roles for the miR‐379/miR‐410 cluster within the imprinted Dlk1‐Dio3 region during this metabolic transition. The miR‐379/miR‐410 locus, also named C14MC in humans, is the largest known placental mammal‐specific miRNA cluster, whose 39 miRNA genes are expressed only from the maternal allele. We found that heterozygote pups with a maternal—but not paternal—deletion of the miRNA cluster display partially penetrant neonatal lethality with defects in the maintenance of energy homeostasis. This maladaptive metabolic response is caused, at least in part, by profound changes in the activation of the neonatal hepatic gene expression program, pointing to as yet unidentified regulatory pathways that govern this crucial metabolic transition in the newborn's liver. Not only does our study highlight the physiological importance of miRNA genes that recently evolved in placental mammal lineages but it also unveils additional layers of RNA‐mediated gene regulation at the Dlk1‐Dio3 domain that impose parent‐of‐origin effects on metabolic control at birth and have likely contributed to mammal evolution.     

Plasma Metabolomic Profiling Suggests Early Indications for Predisposition to Latent Insulin Resistance in Children Conceived by ICSI

Background

There have been increasing indications about an epigenetically-based elevated predisposition of assisted reproductive technology (ART) offspring to insulin resistance, which can lead to an unfavorable cardio-metabolic profile in adult life. However, the relevant long-term systematic molecular studies are limited, especially for the IntraCytoplasmic Sperm Injection (ICSI) method, introduced in 1992. In this study, we carefully defined a group of 42 prepubertal ICSI and 42 naturally conceived (NC) children. We assessed differences in their metabolic profile based on biochemical measurements, while, for a subgroup, plasma metabolomic analysis was also performed, investigating any relevant insulin resistance indices.

Methods & Results

Auxological and biochemical parameters of 42 6.8±2.1 yrs old ICSI-conceived and 42 age-matched controls were measured. Significant differences between the groups were determined using univariate and multivariate statistics, indicating low urea and low-grade inflammation markers (YKL-40, hsCRP) and high triiodothyronine (T3) in ICSI-children compared to controls. Moreover, plasma metabolomic analysis carried out for a subgroup of 10 ICSI- and 10 NC girls using Gas Chromatography-Mass Spectrometry (GC-MS) indicated clear differences between the two groups, characterized by 36 metabolites linked to obesity, insulin resistance and metabolic syndrome. Notably, the distinction between the two girl subgroups was accentuated when both their biochemical and metabolomic measurements were employed.

Conclusions

The present study contributes a large auxological and biochemical dataset of a well-defined group of pre-pubertal ICSI-conceived subjects to the research of the ART effect to the offspring''s health. Moreover, it is the first time that the relevant usefulness of metabolomics was investigated. The acquired results are consistent with early insulin resistance in ICSI-offspring, paving the way for further systematic investigations. These data support that metabolomics may unravel metabolic differences before they become clinically or biochemically evident, underlining its utility in the ART research.     

CRHR1 Receptor binding and lipophilicity of pyrrolopyrimidines, potential nonpeptide corticotropin-releasing hormone type 1 receptor antagonists.

A series of compounds related to N-butyl-N-ethyl[2,5,6-trimethyl-7-(2,4,6-trimethylphenyl)pyrrolo[2,3-d]pyrimidin-4-yl]amine (1, antalarmin) have been prepared and evaluated for their CRHR1 binding affinity as the initial step in the development of selective high affinity hydrophilic nonpeptide corticotropin-releasing hormone type 1 receptor (CRHR1) antagonists. Calculated log P (Clog P) values were used to evaluate the rank order of hydrophilicity for these analogues. Introducing oxygenated functionalities (delta-hydroxy or bis-beta-ethereal) into 1 gave more hydrophilic compounds, which had good affinity for the receptor. Introducing an amino group or shortening the alkyl side chain was detrimental to CRHR1 affinity. The alcohol 4-[ethyl[2,5,6-trimethyl-7-(2,4,6-trimethylphenyl)pyrrolo[2,3-d]pyrimidin-4-yl]amino]butan-1-ol (3), bearing a terminal hydroxyl group on an N-alkyl side-chain, showed the highest CRHR1 binding affinity among these compounds (K(i)=0.68 nM), and is one of the highest affinity CRHR1 ligands known. Compounds 3-5, and 8, which are likely to be less lipophilic than 1, have high CRHR1 affinity and may be valuable probes to further study the CRH system.     

Antiproliferative effect of adiponectin on MCF7 breast cancer cells: a potential hormonal link between obesity and cancer.

Adiponectin, a hormone secreted by adipose tissue, circulates at high concentrations in human plasma. Paradoxically, plasma levels of adiponectin are approximately 50% lower in obese than in lean subjects. An association between low plasma levels of adiponectin and higher risk of developing breast and other cancers was recently reported. Obesity and overweight have also been associated with increased mortality from cancer. To test the hypothesis that adiponectin exerts direct antiproliferative and/or pro-apoptotic effects on cancer cells, we used the MCF7 human breast adenocarcinoma cell line. The proliferation rate of the MCF7 cells was measured using the MTT method, while apoptosis was examined by quantifying the DNA fragmentation using an ELISA assay. In addition, adiponectin receptor 1 (AdipoR1) and AdipoR2 mRNA expression was detected using RT-PCR. Adiponectin diminished the proliferation rate of MCF7 cells; this effect was significant after 48-96 hours of treatment. The presence of receptor expression suggested that the effect of adiponectin on cell proliferation was most likely specific and adiponectin receptor-mediated. Adiponectin induced no apoptosis of MCF7 cells over 48 hours. We conclude that adiponectin inhibits proliferation but causes no apoptosis of MCF7 breast cancer cells. These data suggest that adiponectin may represent a direct hormonal link between obesity and cancer.     

Hemodynamic and endocrine parameters in the anesthetized cynomolgus monkey: a primate model

Hemodynamic and endocrine parameters were determined in nine anesthetized adult male cynomolgus monkeys. Simultaneous phasic and mean pressures were measured in the right atrium, pulmonary artery, and abdominal aorta. Intermittent pulmonary artery wedge pressures and mean cardiac output measured by the thermal dilution method were used to calculate stroke volume, systemic vascular resistance, and pulmonary vascular resistance. Plasma adrenocorticotropic hormone (ACTH), cortisol, and plasma renin activity were measured throughout the procedure. Technical aspects, data in the anesthetized monkey, and comparison with previously reported data are presented.