Background CHD8 (chromodomain helicase DNA-binding protein 8), which codes for a member of the CHD family of ATP-dependent chromatin-remodeling factors, is one of the most commonly mutated genes in autism spectrum disorders (ASD) identified in exome-sequencing studies. Loss of function mutations in the gene have also been found in schizophrenia (SZ) and intellectual disabilities and influence cancer cell proliferation. We previously reported an RNA-seq analysis carried out on neural progenitor cells (NPCs) and monolayer neurons derived from induced pluripotent stem (iPS) cells that were heterozygous for CHD8 knockout (KO) alleles generated using CRISPR-Cas9 gene editing. A significant number of ASD and SZ candidate genes were among those that were differentially expressed in a comparison of heterozygous KO lines (CHD8 +/−) vs isogenic controls (CHD8 +/−), including the SZ and bipolar disorder (BD) candidate gene TCF4, which was markedly upregulated in CHD8 +/− neuronal cells.MethodsIn the current study, RNA-seq was carried out on CHD8 +/− and isogenic control (CHD8 +/+) cerebral organoids, which are 3-dimensional structures derived from iPS cells that model the developing human telencephalon.Results TCF4 expression was, again, significantly upregulated. Pathway analysis carried out on differentially expressed genes (DEGs) revealed an enrichment of genes involved in neurogenesis, neuronal differentiation, forebrain development, Wnt/β-catenin signaling, and axonal guidance, similar to our previous study on NPCs and monolayer neurons. There was also significant overlap in our CHD8 +/− DEGs with those found in a transcriptome analysis carried out by another group using cerebral organoids derived from a family with idiopathic ASD. Remarkably, the top DEG in our respective studies was the non-coding RNA DLX6-AS1, which was markedly upregulated in both studies; DLX6-AS1 regulates the expression of members of the DLX (distal-less homeobox) gene family. DLX1 was also upregulated in both studies. DLX genes code for transcription factors that play a key role in GABAergic interneuron differentiation. Significant overlap was also found in a transcriptome study carried out by another group using iPS cell-derived neurons from patients with BD, a condition characterized by dysregulated WNT/β-catenin signaling in a subgroup of affected individuals.ConclusionsOverall, the findings show that distinct ASD, SZ, and BD candidate genes converge on common molecular targets—an important consideration for developing novel therapeutics in genetically heterogeneous complex traits.Electronic supplementary materialThe online version of this article (doi:10.1186/s13229-017-0124-1) contains supplementary material, which is available to authorized users.

The relationships between urinary prostaglandin E excretion and urine flow rate were evaluated in 11 conscious mongrel dogs during antidiuresis, maximal water loading, vasopressin administration during maximal water loading, and mannitol infusion. Urine flow rates between 0.21 and 15.1 ml/min were achieved. Urinary prostaglandin E excretion rates, determined by a membrane receptor assay, varied directly with urine flow rates (r = 0.908). Vasopressin administration (34--540 microU . kg-1 . min-1) resulted in a fall, rather than the expected rise, in urinary prostaglandin E excretion. When the concentration of prostaglandin E in the urine was plotted against urine flow rate, the demonstrated relationship appeared most consistent with passive diffusion. Mannitol infusion increased urine flow rates to levels comparable to the levels seen with maximal water loading but did not result in a fall in plasma osmolality. Urinary prostaglandin E excretion rates, however, were not distinguishable from those in the previous group. These data demonstrate that urinary prostaglandin E excretion rates are determined, to a great extent, by urine flow rate and that the significance of the interpretation of elevated excretion levels of these lipids in diuretic states may have to be reevaluated.

A B S T R A C T Studies were performed to determine the effect of decreased endogenous release of renal prostaglandins on urinary sodium excretion. Two structurally dissimilar inhibitors of prostaglandin synthesis were employed, and studies were performed in conscious dogs allowed to recover from prior surgical instrumentation. Either meclofenamate (2 mg/kg) or the competitive prostaglandin inhibitor RO 20-5720 (1 mg/kg) was given to seven unanesthetized dogs undergoing a water diuresis. The administration of either prostaglandin inhibitor did not alter glomerular filtration rate, renal plasma flow, urinary volume, or potassium excretion. Sodium excretion, however, increased from 32 to 130 ueq/min (P <0.02). Essentially, the entire increase in sodium excretion was due to an increase in urinary sodium concentration from 7.7 to 28.3 meq/liter (P < 0.02). On a different day, the same animals were studied before and after administration of the diluent of the prostaglandin inhibitor. No change was noted in sodium excretion or any other parameter.Thus, these findings suggest that prostaglandin inhibition in the conscious dog is associated with a natriuresis without a change in urinary volume or potassium excretion during water diuresis. This may indicate that the natriuresis was due to diminished sodium reabsorption beyond the distal tubule.

Although lysophosphatidylcholine (LPC)-mediated cellular responses are attributed to the activation of protein kinase C (PKC), relatively little is known about the upstream signaling mechanisms that regulate the activation of PKC and downstream mitogen-activated protein (MAP) kinase. LPC activated p42 MAP kinase and PKC in mesangial cells. LPC-mediated MAP kinase activation was inhibited (but not completely) by PKC inhibition, suggesting additional signaling events. LPC stimulated protein tyrosine kinase (PTK) activity and induced Ras-GTP binding. LPC-induced MAP kinase activity was blocked by the PTK inhibitor genistein. Because LPC increased PTK activity, we examined the involvement of phospholipase Cγ-1 (PLCγ-1) as a key participant in LPC-induced PKC activation. LPC stimulated the phosphorylation of PLCγ-1. PTK inhibitors suppressed LPC-induced PKC activity, whereas the same had no effect on phorbol 12-myristate 13-acetate-mediated PKC activity. Other lysophospholipids [e.g., lysophosphatidylinositol and lysophosphatidic acid (LPA)] also induced MAP kinase activity, and only LPA-induced MAP kinase activation was sensitive to pertussis toxin. These results indicate that LPC-mediated PKC activation may be regulated by PTK-dependent activation of PLCγ-1, and both PKC and PTK-Ras pathways are involved in LPC-mediated downstream MAP kinase activation.

Intermediary metabolites of cholesterol synthetic pathway are involved in cell proliferation. Lovastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, blocks mevalonate synthesis, and has been shown to inhibit mesangial cell proliferation associated with diverse glomerular diseases. Since inhibition of farnesylation and plasma membrane anchorage of the Ras proteins is one suggested mechanism by which lovastatin prevents cellular proliferation, we investigated the effect of lovastatin and key mevalonate metabolites on the activation of mitogen-activated protein kinase (MAP kinase) and Ras in murine glomerular mesangial cells. The preincubation of mesangial cells with lovastatin inhibited the activation of MAP kinase stimulated by either FBS, PDGF, or EGF. Mevalonic acid and farnesyl-pyrophosphate, but not cholesterol or LDL, significantly prevented lovastatin-induced inhibition of agonist-stimulated MAP kinase. Lovastatin inhibited agonist-induced activation of Ras, and mevalonic acid and farnesylpyrophosphate antagonized this effect. Parallel to the MAP kinase and Ras data, lovastatin suppressed cell growth stimulated by serum, and mevalonic acid and farnesylpyrophosphate prevented lovastatin-mediated inhibition of cellular growth. These results suggest that lovastatin, by inhibiting the synthesis of farnesol, a key isoprenoid metabolite of mevalonate, modulates Ras-mediated cell signaling events associated with mesangial cell proliferation.

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Aim Manually explore the Google search queries of individuals with first episode psychosis prior to their first hospitalization, in effort to identify common themes and search interests during the period of emerging illness. Methods Individuals hospitalized for psychosis between December 2016 and September 2017 provided access to their Google archive data for manual qualitative evaluation of search content. Searches conducted during the 6‐month time period prior to the participant's first hospitalization for psychosis were extracted and evaluated for search activity associated with mental health. Results Of 20 archives reviewed, 15 individuals (75%) searched for information classified by reviewers as related to mental health. Searches with content associated with delusions were found in 15 participant archives (75%). Searches related to negative symptoms including social withdrawal and decline in function were identified in 6 participant's search archives (30%). Four participants (20%) had searches that were associated with thought processes, and 2 participants (10%) searched for information on suicide. Four participants (20%) searched for information related to anxiety, whereas 3 participants (15%) had searches related to depressive symptoms. Conclusions Individuals with early psychosis appear to be using the Internet for obtaining information about their early symptoms and experiences prior to their first contact with psychiatric care. Improving our understanding of the ways by which individuals with emerging psychosis search for information about their experiences online may help mental health clinicians tailor online resources in hopes of improving pathways to care and reducing the duration of untreated psychosis.

Disordered lipoprotein metabolism and the enhanced influx and accumulation of circulating mononuclear leukocytes into vascular tissue are common pathobiological phenomena associated with both atherosclerosis and glomerulosclerosis. Since atherogenic lipoproteins (such as low density lipoprotein, LDL) have been implicated in monocyte migration and proliferation into the glomerular mesangium, we examined the effect of LDL on mesangial cell expression of macrophage colony-stimulating factor (M-CSF), a cytoregulatory peptide associated with monocyte chemoattraction, differentiation and proliferation. Mesangial cell M-CSF gene expression, protein synthesis and secretion, and its biological activity to induce progenitor colony formation and monocyte proliferation were studied in murine mesangial cells. Incubation of either primary cultures or SV-40 transformed murine mesangial cells with LDL (0 to 200 micrograms/ml) induced M-CSF steady-state mRNA expression, in a dose-dependent manner (52 to 183% of control) when Northern blots were analyzed quantitatively by densitometric scanning. Similarly, Western blot analysis showed that LDL-activated SV-40 transformed mesangial cells increased M-CSF protein synthesis and secretion in a dose-dependent manner. The conditioned media obtained by incubating mesangial cells with LDL induced bone marrow progenitor colony formation that could be inhibited by specific neutralizing antibodies against murine M-CSF. Finally, the biological activity of M-CSF secreted by LDL-activated mesangial cells was further confirmed by its enhanced ability to induce monocyte proliferation. These data indicate that LDL, by activating mesangial cells to induce M-CSF and possibly other monocyte chemoattractants, may regulate the migration and proliferation of cells of mononuclear leukocytic origin into the mesangium supporting a pathobiological role for LDL in glomerular injury.