Telomere length in offspring is determined by mitochondrial-nuclear communication at fertilization.

The initial setting of telomere length during early life in each individual has a major influence on lifetime risk of aging-associated diseases; however there is limited knowledge of biological signals that regulate inheritance of telomere length, and whether it is modifiable is not known. We now show that when mitochondrial activity is disrupted in mouse zygotes, via exposure to 20% O or rotenone, telomere elongation between the 8-cell and blastocyst stage is impaired, with shorter telomeres apparent in the pluripotent Inner Cell Mass (ICM) and persisting after organogenesis. Identical defects of elevated mtROS in zygotes followed by impaired telomere elongation, occurred with maternal obesity or advanced age.

Clinician Perspectives on the Impact of COVID-19 on the Treatment of Adults and Youth with Anxiety.

We describe the perceptions of mental health clinicians practicing in the United States about the effects of the COVID-19 pandemic on the presentation and treatment course of active clients with anxiety. Clinician participants reported on client symptomology at the beginning of treatment, just before (prior to March 2020), and at a mid-pandemic timepoint (December 2020/January 2021). An initial sample of 70 clinicians responded to a survey assessing their clients' overall anxiety severity, anxiety sensitivity, pathological uncertainty, family accommodation, and avoidance levels.

Placental microRNA dataset of monochorionic twin pregnancies with and without selective fetal growth restriction.

To compare the whole genomic microRNA (miRNA) between the selective fetal growth restriction (sFGR) twin and the normally growing (control) co-twin in monochorionic (MC) twin pregnancies. MC twin pregnancies with or without sFGR were recruited, and their placental miRNAs were profiled by microarray. The ratio of the placental miRNA of the sFGR twin to that of the normally larger co-twin were calculated and compared to that of the control twin pairs.

Differential impacts of gonadotrophins, IVF and embryo culture on mouse blastocyst development.

Research Question: Conception via assisted reproductive technology (ART) increases the risk of type 2 diabetes and cardiovascular disease in adulthood. Underlying differences between ART-conceived and in-vivo-conceived embryos that contribute to this increased risk are, however, not known.

Design: This study examined the developmental characteristics of mouse blastocysts derived from ART- compared with in-vivo-conceived embryos.

HAP1 Is Required for Endocytosis and Signalling of BDNF and Its Receptors in Neurons.

When BDNF binds to its receptors, TrkB and p75, the BDNF-receptor complex is endocytosed and trafficked to the cell body for downstream signal transduction, which plays a critical role in neuronal functions. Huntingtin-associated protein 1 (HAP1) is involved in trafficking of vesicles intracellularly and also interacts with several membrane proteins including TrkB. Although it has been known that HAP1 has functions in vesicular trafficking and receptor stabilisation, it is not yet established whether HAP1 has a role in BDNF and its receptor endocytosis.

Nonesterified Fatty Acid-Induced Endoplasmic Reticulum Stress in Cattle Cumulus Oocyte Complexes Alters Cell Metabolism and Developmental Competence.

Reduced oocyte quality has been associated with poor fertility of high-performance dairy cows during peak lactation, due to negative energy balance. We examined the role of nonesterified fatty acids (NEFAs), known to accumulate within follicular fluid during under- and overnutrition scenarios, in causing endoplasmic reticulum (ER) stress of in vitro maturated cattle cumulus-oocyte complexes (COCs). NEFA concentrations were: palmitic acid (150 μM), oleic acid (200 μM), and steric acid (75 μM).

Female offspring sired by diet induced obese male mice display impaired blastocyst development with molecular alterations to their ovaries, oocytes and cumulus cells.

Purpose: To investigate the impacts that a paternal high fat diet (HFD) has on embryology, ovarian/cumulus cell gene expression and COC metabolism from female offspring, using a mouse model.

Methods: Founder male mice were either fed a control diet (CD) or a HFD for 12 weeks. The HFD induced obesity but not diabetes, and founder males were then mated to normal weight CD fed female mice.

Distinct localisation of lipids in the ovarian follicular environment.

Obesity is associated with decreased pregnancy rates due, in part, to compromised oocyte quality. The aim of the present cross-sectional study of 84 women undergoing oocyte aspiration was to: (1) compare insulin, lipids and glucose in follicular fluid with serum; (2) determine whether increased body mass index (BMI) and waist circumference, hyperinsulinaemia, dyslipidaemia or metabolic syndrome altered follicular fluid metabolites; and (3) determine relative lipid content in oocytes to reveal any influence of these parameters on oocyte quality and IVF outcomes. Insulin, glucose, triglyceride and free fatty acids were lower in follicular fluid than blood and not strictly correlated between compartments.

Hyperglycaemia and lipid differentially impair mouse oocyte developmental competence.

Maternal diabetes and obesity are characterised by elevated blood glucose, insulin and lipids, resulting in upregulation of specific fuel-sensing and stress signalling pathways. Previously, we demonstrated that, separately, upregulation of the hexosamine biosynthetic pathway (HBP; under hyperglycaemic conditions) and endoplasmic reticulum (ER) stress (due to hyperlipidaemia) pathways reduce blastocyst development and alter oocyte metabolism. In order to begin to understand how both glucose and lipid metabolic disruptions influence oocyte developmental competence, in the present study we exposed mouse cumulus-oocyte complexes to hyperglycaemia (30mM) and/or lipid (40μM) and examined the effects on embryo development.

Mitochondrial dysfunction in oocytes of obese mothers: transmission to offspring and reversal by pharmacological endoplasmic reticulum stress inhibitors.

Over-nutrition in females causes altered fetal growth during pregnancy and permanently programs the metabolism of offspring; however, the temporal and mechanistic origins of these changes, and whether they are reversible, are unknown. We now show that, in obese female mice, cumulus-oocyte complexes exhibit endoplasmic reticulum (ER) stress, high levels of intracellular lipid, spindle abnormalities and reduced PTX3 extracellular matrix protein production. Ovulated oocytes from obese mice contain normal levels of mitochondrial (mt) DNA but have reduced mitochondrial membrane potential and high levels of autophagy compared with oocytes from lean mice.

Exposure to lipid-rich follicular fluid is associated with endoplasmic reticulum stress and impaired oocyte maturation in cumulus-oocyte complexes.

Objective: To determine whether the high lipid content of human follicular fluid influences oocyte maturation.

Design: Mouse oocytes as substitutes for human oocytes were exposed to follicular fluids of differing lipid content with outcome monitoring.

Setting: Private infertility clinic and university laboratory.

The impact of obesity on oocytes: evidence for lipotoxicity mechanisms.

Obesity can have detrimental effects on pregnancy rates in natural conceptions and also in women undergoing IVF or intracytoplasmic sperm injection (ICSI). This review summarises the most recent clinical literature investigating whether obesity impacts oocyte quality and early embryo growth. In other tissues, obesity leads to lipotoxicity responses including endoplasmic reticulum stress, mitochondrial dysfunction and apoptosis.

Endoplasmic reticulum (ER) stress in cumulus-oocyte complexes impairs pentraxin-3 secretion, mitochondrial membrane potential (DeltaPsi m), and embryo development.

Fatty acids such as palmitic acid at high levels are known to induce endoplasmic reticulum (ER) stress and lipotoxicity in numerous cell types and thereby contribute to cellular dysfunctions in obesity. To understand the impact of high fatty acids on oocytes, ER stress and lipotoxicity were induced in mouse cumulus-oocyte complexes during in vitro maturation using the ER Ca(2+) channel blocker thapsigargin or high physiological levels of palmitic acid; both of which significantly induced ER stress marker genes (Atf4, Atf6, Xbp1s, and Hspa5) and inositol-requiring protein-1α phosphorylation, demonstrating an ER stress response that was reversible with the ER stress inhibitor salubrinal. Assessment of pentraxin-3, an extracellular matrix protein essential for fertilization, by immunocytochemistry and Western blotting showed dramatically impaired secretion concurrent with ER stress.

Inflammatory pathways linking obesity and ovarian dysfunction.

This review summarizes some of the recent advances in obesity research and describes how we and others have built upon these findings to better understand the impact of obesity on granulosa cells, cumulus cells and oocytes within the ovaries of obese females. Obesity is associated with lipid accumulation in non-adipose tissue cells and the induction of oxidative stress and endoplasmic reticulum stress responses that are tightly linked with systemic inflammation. Analysis of ovarian cells and fluid of obese women indicates that these same mechanisms are activated in the ovary in response to obesity.

Identification of perilipin-2 as a lipid droplet protein regulated in oocytes during maturation.

Lipid droplet proteins regulate the storage and utilisation of intracellular lipids. Evidence is emerging that oocyte lipid utilisation impacts embryo development, but lipid droplet proteins have not been studied in oocytes. The aim of the present study was to characterise the size and localisation of lipid droplets in mouse oocytes during the periovulatory period and to identify lipid droplet proteins as potential biomarkers of oocyte lipid content.

High-fat diet causes lipotoxicity responses in cumulus-oocyte complexes and decreased fertilization rates.

In obesity, accumulation of lipid in nonadipose tissues, or lipotoxicity, is associated with endoplasmic reticulum (ER) stress, mitochondrial dysfunction, and ultimately apoptosis. We have previously shown that obese women have increased triglycerides in follicular fluid; thus, the present study examined whether high-fat diet-induced obesity causes lipotoxicity in granulosa cells and the cumulus-oocyte complex (COC). Oocytes of mice fed a high-fat diet had dramatically increased lipid content and reduced mitochondrial membrane potential compared to those of mice fed a control diet.

Huntingtin-associated protein-1 interacts with pro-brain-derived neurotrophic factor and mediates its transport and release.

Brain-derived neurotrophic factor (BDNF) plays a pivotal role in brain development and synaptic plasticity. It is synthesized as a precursor (pro-BDNF), sorted into the secretory pathway, transported along dendrites and axons, and released in an activity-dependent manner. Mutant Huntingtin with expanded polyglutamine (polyQ) and the V66M polymorphism of BDNF reduce the dendritic distribution and axonal transport of BDNF.

Huntingtin associated protein 1 and its functions.

Huntington disease (HD) is caused by a polyglutamine expansion in the protein huntingtin (Htt). Several studies suggest that Htt and huntingtin associated protein 1 (HAP1) participate in intracellular trafficking and that polyglutamine expansion affects vesicular transport. Understanding the function of HAP1 and its related proteins could help elucidate the pathogenesis of HD.

Differential effects of pro-BDNF on sensory neurons after sciatic nerve transection in neonatal rats.

Brain-derived neurotrophic factor (BDNF) plays a critical role in the development of the central and peripheral nervous systems, and also in neuronal survival after injury. The actions of BDNF are mediated by its high-affinity receptors TrkB and p75NTR. Recent studies have shown that proneurotrophins bind p75NTR and sortilin with high affinity, and trigger apoptosis of neurons in vitro.

Axonal transport of BDNF precursor in primary sensory neurons.

Recent studies have shown that the precursor of brain-derived neurotrophic factor (pro-BDNF) activates p75NTR with high affinity to induce apoptosis. Here we show that pro-BDNF is transported anterogradely and retrogradely in sensory neurons of adult rats. After a crush injury of sciatic nerves, dorsal roots or dorsal column in adult Sprague-Dawley rats, the immunoreactivity for pro-BDNF accumulated at both the proximal and distal segments.

Knockout of p75(NTR) impairs re-myelination of injured sciatic nerve in mice.

Remyelination is an important aspect of nerve regeneration after nerve injury but the underlying mechanisms are not fully understood. The neurotrophin receptor, p75(NTR), in activated Schwann cells in the Wallerian degenerated nerve is up-regulated and may play a role in the remyelination of regenerating peripheral nerves. In the present study, the role of p75(NTR) in remyelination of the sciatic nerve was investigated in p75(NTR) mutant mice.