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Reviews the morphogenesis of the heart and discusses research findings on the cardiac homeodomain factor Nkx2-5. Information on the secondary heart field and extra-cardiac lineages; Building blocks of the heart; Association between Nkx2-5 and cardiac transcription factor pathways; Regulators of chamber myocardium.

Purpose: To evaluate the safety and tolerability of single and multiple intravitreal injections of NGM621 in patients with geographic atrophy (GA) and to characterize the pharmacokinetics and immunogenic potential., Design: Multicenter, open-label, single- and multiple-dose phase 1 study., Methods: Fifteen patients enrolled at 4 sites in the United States. Participants had GA secondary to age-related macular degeneration, lesion size ≥2.5 mm 2 , best-corrected visual acuity of 4 to 54 letters (20/80 to 20/800 Snellen equivalent) in the study eye, and no history of choroidal neovascularization in either eye. Patients who met eligibility criteria were treated in a single ascending-dose phase (2 mg, 7.5 mg, and 15 mg) or received 2 doses of NGM621 (15 mg) 4 weeks apart in the multidose phase and were monitored for 12 weeks (85 days). Assessments included adverse events, best-corrected visual acuity, low-luminance visual acuity, vital signs, clinical laboratory evaluations, GA lesion area as measured by fundus autofluorescence, spectral domain optical coherence tomography, and pharmacokinetic, immunogenicity, and pharmacodynamic assessments., Results: All 15 participants completed the 12-week study. There were no serious adverse events, no drug-related adverse events, and no choroidal neovascularization developed in either eye. Mean visual acuity and GA lesion area appeared stable through week 12 for all cohorts. Pharmacokinetic analyses indicated that NGM621 serum exposures appeared to be dose proportional, and no antidrug antibodies were identified at any of the evaluated time points., Conclusions: In this small, open-labeled, 12-week phase 1 study, NGM621 was safe and tolerable when administered intravitreally up to 15 mg.., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

This corrects the article DOI: 10.1038/nature24042.

Under homeostatic conditions, animals use well-defined hypothalamic neural circuits to help maintain stable body weight, by integrating metabolic and hormonal signals from the periphery to balance food consumption and energy expenditure. In stressed or disease conditions, however, animals use alternative neuronal pathways to adapt to the metabolic challenges of altered energy demand. Recent studies have identified brain areas outside the hypothalamus that are activated under these 'non-homeostatic' conditions, but the molecular nature of the peripheral signals and brain-localized receptors that activate these circuits remains elusive. Here we identify glial cell-derived neurotrophic factor (GDNF) receptor alpha-like (GFRAL) as a brainstem-restricted receptor for growth and differentiation factor 15 (GDF15). GDF15 regulates food intake, energy expenditure and body weight in response to metabolic and toxin-induced stresses; we show that Gfral knockout mice are hyperphagic under stressed conditions and are resistant to chemotherapy-induced anorexia and body weight loss. GDF15 activates GFRAL-expressing neurons localized exclusively in the area postrema and nucleus tractus solitarius of the mouse brainstem. It then triggers the activation of neurons localized within the parabrachial nucleus and central amygdala, which constitute part of the 'emergency circuit' that shapes feeding responses to stressful conditions. GDF15 levels increase in response to tissue stress and injury, and elevated levels are associated with body weight loss in numerous chronic human diseases. By isolating GFRAL as the receptor for GDF15-induced anorexia and weight loss, we identify a mechanistic basis for the non-homeostatic regulation of neural circuitry by a peripheral signal associated with tissue damage and stress. These findings provide opportunities to develop therapeutic agents for the treatment of disorders with altered energy demand.

US children with emotional, mental, or behavioral conditions (EMB) have disproportionate exposure to adverse childhood experiences (ACEs). There are theoretic and empirical explanations for early and lifelong physical, mental, emotional, educational, and social impacts of the resultant trauma and chronic stress. Using mindfulness-based, mind-body approaches (MBMB) may strengthen families and promote child resilience and success. This paper examines associations between EMB, ACEs, and protective factors, such as child resilience, parental coping/stress, and parent-child engagement. Findings encourage family-centered and mindfulness-based approaches to address social and emotional trauma and potentially interrupt cycles of ACEs and prevalence of EMB., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The molecular determinants of spleen organogenesis and the etiology of isolated congenital asplenia (ICA), a life-threatening human condition, are unknown. We previously reported that Pbx1 deficiency causes organ growth defects including asplenia. Here, we show that mice with splenic mesenchyme-specific Pbx1 inactivation exhibit hyposplenia. Moreover, the loss of Pbx causes downregulation of Nkx2-5 and derepression of p15Ink4b in spleen mesenchymal progenitors, perturbing the cell cycle. Removal of p15Ink4b in Pbx1 spleen-specific mutants partially rescues spleen growth. By whole-exome sequencing of a multiplex kindred with ICA, we identify a heterozygous missense mutation (P236H) in NKX2-5 showing reduced transactivation in vitro. This study establishes that a Pbx/Nkx2-5/p15 regulatory module is essential for spleen development., (Copyright © 2012 Elsevier Inc. All rights reserved.)

β-Catenin-dependent Wnt signaling is initiated as Wnt binds to both the receptor FZD and coreceptor LRP5/6, which then assembles a multimeric complex at the cytoplasmic membrane face to recruit and inactivate the kinase GSK3. The large number and sequence diversity of Wnt isoforms suggest the possibility of domain-specific ligand-coreceptor interactions, and distinct binding sites on LRP6 for Wnt3a and Wnt9b have recently been identified in vitro. Whether mechanistically different interactions between Wnts and coreceptors might mediate signaling remains to be determined. It is also not clear whether coreceptor homodimerization induced extracellularly can activate Wnt signaling, as is the case for receptor tyrosine kinases. We generated monoclonal antibodies against LRP6 with the unexpected ability to inhibit signaling by some Wnt isoforms and potentiate signaling by other isoforms. In cell culture, two antibodies characterized further show reciprocal activities on most Wnts, with one antibody antagonizing and the other potentiating. We demonstrate that these antibodies bind to different regions of LRP6 protein, and inhibition of signaling results from blocking Wnt binding. Antibody-mediated dimerization of LRP6 can potentiate signaling only when a Wnt isoform is also able to bind the complex, presumably recruiting FZD. Endogenous autocrine Wnt signaling in different tumor cell lines can be either antagonized or enhanced by the LRP6 antibodies, indicating expression of different Wnt isoforms. As anticipated from the roles of Wnt signaling in cancer and bone development, antibody activities can also be observed in mice for inhibition of tumor growth and in organ culture for enhancement of bone mineral density. Collectively, our results indicate that separate binding sites for different subsets of Wnt isoforms determine the inhibition or potentiation of signaling conferred by LRP6 antibodies. This complexity of coreceptor-ligand interactions may allow for differential regulation of signaling by Wnt isoforms during development, and can be exploited with antibodies to differentially manipulate Wnt signaling in specific tissues or disease states.

Large collections of knockout organisms facilitate the elucidation of gene functions. Here we used retroviral insertion or homologous recombination to disrupt 472 genes encoding secreted and membrane proteins in mice, providing a resource for studying a large fraction of this important class of drug target. The knockout mice were subjected to a systematic phenotypic screen designed to uncover alterations in embryonic development, metabolism, the immune system, the nervous system and the cardiovascular system. The majority of knockout lines exhibited altered phenotypes in at least one of these therapeutic areas. To our knowledge, a comprehensive phenotypic assessment of a large number of mouse mutants generated by a gene-specific approach has not been described previously.

Precise regulation of Wnt signaling is important in many contexts, as in development of the vertebrate forebrain, where excessive or ectopic Wnt signaling leads to severe brain defects. Mutation of the widely expressed oto gene causes loss of the anterior forebrain during mouse embryogenesis. Here we report that oto is the mouse ortholog of the gpi deacylase gene pgap1, and that the endoplasmic reticulum (ER)-resident Oto protein has a novel and deacylase-independent function during Wnt maturation. Oto increases the hydrophobicities of Wnt3a and Wnt1 by promoting the addition of glycophosphatidylinositol (gpi)-like anchors to these Wnts, which results in their retention in the ER. We also report that oto-deficient embryos exhibit prematurely robust Wnt activity in the Wnt1 domain of the early neural plate. We examine the effect of low oto expression on Wnt1 in vitro by knocking down endogenous oto expression in 293 and M14 melanoma cells using shRNA. Knockdown of oto results in increased Wnt1 secretion which is correlated with greatly enhanced canonical Wnt activity. These data indicate that oto deficiency increases Wnt signaling in vivo and in vitro. Finally, we address the mechanism of Oto-mediated Wnt retention under oto-abundant conditions, by cotransfecting Wnt1 with gpi-specific phospholipase D (GPI-PLD). The presence of GPI-PLD in the secretory pathway results in increased secretion of soluble Wnt1, suggesting that the gpi-like anchor lipids on Wnt1 mediate its retention in the ER. These data now provide a mechanistic framework for understanding the forebrain defects in oto mice, and support a role for Oto-mediated Wnt regulation during early brain development. Our work highlights a critical role for ER retention in regulating Wnt signaling in the mouse embryo, and gives insight into the notoriously inefficient secretion of Wnts.

Background: While most people die in the hospital or a nursing home, surveys indicate that more than 70% of people would prefer to die at home. Expert panel recommendations have called for epidemiologic studies to document the nature of dying in America., Objective: To determine if the experience of dying differed among settings in New Hampshire., Design: A voluntary, statewide medical record audit of adult deaths in hospitals, nursing homes and home care/hospice agencies was conducted for February and March 2002., Measurements: Records were examined for place of death, patient decision-making capacity and advance directives (ADs). Information was collected on demographic characteristics, primary and secondary diagnoses, presence of a "values history" (documented discussion with patient about their values and end-of-life care) and whether emotional and spiritual support was provided to patients and their families. Medical chart notes for the 48 hours preceding death were reviewed for "pain" and "other symptoms routinely assessed, treated and documented," and for whether the patient had undergone any of the following "treatments": surgery, ventilator, cardiopulmonary resuscitation, or extubation., Results: Nearly one third (32%) of health care organizations in the state reported on 782 deaths (424 hospital, 148 nursing home, and 210 home care/hospice) representing 44% of the adult deaths during this period. Significant differences among settings (p < 0.001) were found for mean age, gender, marital status, primary insurance, diagnosis, ADs, symptom assessment, and provision of emotional and spiritual support for patients and families. Among hospital decedents, 56% were in acute care beds, 30% were in intensive care units, and 4% were in palliative care beds. Nineteen percent of decedents received interventions such as extubation, placed on a ventilator or surgery in the 48 hours preceding death. Over 80% had a do-not-resuscitate (DNR) order, 45% had a Durable Power of Attorney for Health Care, and 37% had a Living Will. Age and setting were significant factors in the presence of ADs., Conclusions: This information provides a benchmark for different care systems to identify areas for improvements in end-of-life care.

The mature heart valves and septa are derived from the cardiac cushions which initially form as local outgrowths of mesenchymal cells within the outflow tract and atrioventricular regions. Endocardial cells respond to signals from the overlying myocardium and undergo an epithelial-to-mesenchymal transformation to invade the intervening extracellular matrix. The molecules that can induce and maintain these cell populations are not known, but many candidates, including several TGFbetas and BMPs, have been proposed based on their expression patterns and activities in other systems. In the present study, we describe the expression of Bmp6 and Bmp7 in overlapping and adjacent sites, including the cardiac cushions during mouse embryonic development. Previous analyses demonstrate that neither of these BMPs is required during cardiogenesis, but analysis of Bmp6;Bmp7 double mutants uncovers a marked delay in the formation of the outflow tract endocardial cushions. A proportion of Bmp6;Bmp7 mutants also display defects in valve morphogenesis and chamber septation, and the embryos die between 10.5 and 15.5 dpc due to cardiac insufficiency. These data provide the first genetic evidence that BMPs are involved in the formation of the cardiac cushions., (Copyright 2001 Academic Press.)

Bmp6, a member of the 60A subgroup of bone morphogenetic proteins (BMPs), is expressed in diverse sites in the developing mouse embryo from preimplantation stages onwards. To evaluate roles for Bmp6 signaling in vivo, gene targeting was used to generate a null mutation at the Bmp6 locus. The resulting Bmp6 mutant mice are viable and fertile, and show no overt defects in tissues known to express Bmp6 mRNA. The skeletal elements of newborn and adult mutants are indistinguishable from wild-type. However, careful examination of skeletogenesis in late gestation embryos reveals a consistent delay in ossification strictly confined to the developing sternum. In situ hybridization studies in the developing long bones and sternum show that other BMP family members are expressed in overlapping domains. In particular we find that Bmp2 and Bmp6 are coexpressed in hypertrophic cartilage, suggesting that Bmp2 may functionally compensate in Bmp6 null mice. The defects in sternum development in Bmp6 null mice are likely to be associated with a transient early expression of Bmp6 in the sternal bands, prior to ossification. These sternal defects are slightly exacerbated in Bmp5/6 double mutant animals.