Schizophrenia-Like Behaviors Arising from Dysregulated Proline Metabolism Are Associated with Altered Neuronal Morphology and Function in Mice with Hippocampal PRODH Deficiency.

Despite decades of research being conducted to understand what physiological deficits in the brain are an underlying basis of psychiatric diseases like schizophrenia, it has remained difficult to establish a direct causal relationship between neuronal dysfunction and specific behavioral phenotypes. Moreover, it remains unclear how metabolic processes, including amino acid metabolism, affect neuronal function and consequently modulate animal behaviors. PRODH, which catalyzes the first step of proline degradation, has been reported as a susceptibility gene for schizophrenia. It has consistently been shown that PRODH knockout mice exhibit schizophrenia-like behaviors. However, whether the loss of PRODH directly impacts neuronal function or whether such neuronal deficits are linked to schizophrenia-like behaviors has not yet been examined. Herein, we first ascertained that dysregulated proline metabolism in humans is associated with schizophrenia. We then found that PRODH was highly expressed in the oreins layer of the mouse dorsal hippocampus. By using AAV- mediated shRNA, we depleted PRODH expression in the mouse dorsal hippocampus and subsequently observed hyperactivity and impairments in the social behaviors, learning, and memory of these mice. Furthermore, the loss of PRODH led to altered neuronal morphology and function both in vivo and in vitro. Our study demonstrates that schizophrenia-like behaviors may arise from dysregulated proline metabolism due to the loss of PRODH and are associated with altered neuronal morphology and function in mice.

The Roles of Histamine Receptor 1 (hrh1) in Neurotransmitter System Regulation, Behavior, and Neurogenesis in Zebrafish.

Histamine receptors mediate important physiological processes and take part in the pathophysiology of different brain disorders. Histamine receptor 1 (HRH1) is involved in the development of neurotransmitter systems, and its role in neurogenesis has been proposed. Altered HRH1 binding and expression have been detected in the brains of patients with schizophrenia, depression, and autism. Our goal was to assess the role of hrh1 in zebrafish development and neurotransmitter system regulation through the characterization of hrh1-/- fish generated by the CRISPR/Cas9 system. Quantitative PCR, in situ hybridization, and immunocytochemistry were used to study neurotransmitter systems and genes essential for brain development. Additionally, we wanted to reveal the role of this histamine receptor in larval and adult fish behavior using several quantitative behavioral methods including locomotion, thigmotaxis, dark flash and startle response, novel tank diving, and shoaling behavior. Hrh1-/- larvae displayed normal behavior in comparison with hrh1+/+ siblings. Interestingly, a transient abnormal expression of important neurodevelopmental markers was evident in these larvae, as well as a reduction in the number of tyrosine hydroxylase 1 (Th1)-positive cells, th1 mRNA, and hypocretin (hcrt)-positive cells. These abnormalities were not detected in adulthood. In summary, we verified that zebrafish lacking hrh1 present deficits in the dopaminergic and hypocretin systems during early development, but those are compensated by the time fish reach adulthood. However, impaired sociability and anxious-like behavior, along with downregulation of choline O-acetyltransferase a and LIM homeodomain transcription factor Islet1, were displayed by adult fish.

Assessment of Stakeholder Perceptions and Cost of Implementing a Telemedicine Specialty Program at Correctional Facilities in North Carolina.

Background Delivering in-person health care to the more than 1.2 million incarcerated adults can be expensive, logistically challenging, fragmented, and pose security risks. The purpose of this study was to evaluate the implementation of a specialty care telemedicine program in statewide prisons in North Carolina during the COVID-19 pandemic. Methods We evaluated the first 6 months of implementation of a new telemedicine program to deliver specialty care to adults incarcerated in 55 North Carolina prison facilities. We measured patient and practitioner perceptions and the impact on the cost of care. Results A total of 3232 telemedicine visits were completed across 55 prisons within the first 6 months of the program. Most patients reported that the ability to use telemedicine contributed to their overall personal well-being and safety. Many practitioners found that working with the on-site nursing staff to conduct physical exams and to make collective decisions were key drivers to the success of telemedicine. A direct relationship was found between the telemedicine experience and patients' preference for future visits such that as satisfaction increased, the desire to use telemedicine increased. Telemedicine reduced total costs of care by $416,020 (net: -$95,480) within the first 6 months, and $1,195,377 estimated in the first 12 months postimplementation (95% confidence interval: $1,100,166-$1,290,587). Conclusions Implementing specialty care telemedicine in prison facilities enhanced patient and practitioner experiences and reduced costs within the prison system. The implementation of telemedicine in prison systems can increase access to care and reduce public safety risks by eliminating unnecessary off-site medical center visits.

Global determination of reaction rates and lipid turnover kinetics in Mus musculus.

Metabolism is fundamental to life, but measuring metabolic reaction rates remains challenging. Here, we applied C13 fluxomics to monitor the metabolism of dietary glucose carbon in 12 tissues, 9 brain compartments, and over 1,000 metabolite isotopologues over a 4-day period. The rates of 85 reactions surrounding central carbon metabolism are determined with elementary metabolite unit (EMU) modeling. Lactate oxidation, not glycolysis, occurs at a comparable pace with the tricarboxylic acid cycle (TCA), supporting lactate as the primary fuel. We expand the EMU framework to track and quantify metabolite flows across tissues. Specifically, multi-organ EMU simulation of uridine metabolism shows that tissue-blood exchange, not synthesis, controls nucleotide homeostasis. In contrast, isotopologue fingerprinting and kinetic analyses reveal the brown adipose tissue (BAT) having the highest palmitate synthesis activity but no apparent contribution to circulation, suggesting a tissue-autonomous synthesis-to-burn mechanism. Together, this study demonstrates the utility of dietary fluxomics for kinetic mapping in vivo and provides a rich resource for elucidating inter-organ metabolic cross talk.

Proline Metabolism in Neurological and Psychiatric Disorders.

Proline plays a multifaceted role in protein synthesis, redox balance, cell fate regulation, brain development, and other cellular and physiological processes. Here, we focus our review on proline metabolism in neurons, highlighting the role of dysregulated proline metabolism in neuronal dysfunction and consequently neurological and psychiatric disorders. We will discuss the association between genetic and protein function of enzymes in the proline pathway and the development of neurological and psychiatric disorders. We will conclude with a potential mechanism of proline metabolism in neuronal function and mental health.

Changes in Patient Characteristics and Practice Outcomes of a Tele-Urgent Care Clinic Pre- and Post-COVID-19 Telehealth Policy Expansions.

Introduction: The coronavirus 2019 pandemic (COVID-19) has resulted in major changes in lifestyle practices and healthcare delivery. The goal of this study was to examine changes in practice and service outcomes in a telehealth program before and after the federal and private telehealth policy expansion during the COVID-19 pandemic. These findings are particularly useful to understand what may be needed to overcome telehealth challenges in future disasters. Methods: We conducted a cross-sectional analysis of virtual visits through a statewide telehealth center embedded in a large academic healthcare system. Primary outcomes of this study were changes in telehealth visits pre- and post-policy expansions among at-risk populations. Results: A total of 2,132 telehealth visits were conducted: 1,530 (71.8 percent) patients were female, 1,561 (73.2 percent) were between the ages 18-50, 1,576 (74 percent) were uninsured, and 1,225 (57.5 percent) were from rural regions. The average number of telehealth visits per day increased from 14 to 33 visits post-expansion. A significant change in patient characteristics was found among senior, uninsured, and rural patients after the telehealth expansion.There was an 11 percent decrease in telehealth visits from very high vulnerability regions post-expansion compared to pre-expansion. There was a 15 percent decrease in visits resulting in prescription post-expansion (p-value<0.01). Conclusions: COVID-19 policy expansions expanded telehealth utilization among at-risk populations such as senior, uninsured, and rural patients while decompressing hospitals and emergency rooms and maintaining positive patient experiences. Further regulations are needed around virtual visits unintended consequences, software certification, and guidelines for workforce training.

Digital Health Experiences of Incarcerated Populations Using Telemedicine in North Carolina Prisons.

More than 1.2 million adults are incarcerated in the United States and hence, require health care from prison systems. The current delivery of care to incarcerated individualss is expensive, logistically challenging, risk fragmenting care, and pose security risks. The purpose of this study was to evaluate the association of patient characteristics and experiences with the perceived telemedicine experiences of incarcerated individuals during the pandemic. We conducted a cross-sectional study of incarcerated individuals in 55 North Carolina prison facilities seeking medical specialty care via telemedicine. Data collection took place from June 1, 2020 to November 30, 2020. Of the 482 patient surveys completed, 424 (88%) were male, 257 (53.3%) were over 50 years of age, and 225 (46.7%) were Black or African American and 195 (40.5%) were White, and 289 (60%) no prior telemedicine experience. There were 3 strong predictors of how patients rated their telemedicine experience: personal comfort with telemedicine (P-value < .001), wait time (P-value < .001), and the clarity of the treatment explanation by the provider (P-value < .001). There was a relationship between telemedicine experiences and how patient rated their experience. Also, patients who were less satisfied with using telemedicine indicated their preference for an in-clinic visit for their next appointment.

Association between lncRNA-H19 polymorphisms and hepatoblastoma risk in an ethic Chinese population.

H19 polymorphisms are associated with increased susceptibility to several cancers; however, their role in hepatoblastoma remains unclear. In this study, we investigated the association between three H19 polymorphisms (rs2839698 G>A, rs3024270 C>G, rs217727 G>A) and hepatoblastoma susceptibility in 213 hepatoblastoma patients. The rs2839698 and rs3024270 polymorphisms were associated with significantly increased hepatoblastoma risk, with the GG genotype associated with a higher risk of hepatoblastoma than the CC genotype at the rs3024270 locus. The rs217727 polymorphism was associated with significantly decreased hepatoblastoma risk, with the AG genotype associated with a lower risk of hepatoblastoma than the GG genotype. These findings were confirmed by combined analysis, and stratification analysis revealed that age, gender and clinical stage were associated with increased hepatoblastoma susceptibility. The GGG and AGG haplotypes were significantly associated with increased hepatoblastoma risk compared with the GCA reference (rs2839698, rs3024270, rs217727). The rs2839698 and rs3024270 polymorphisms correlated with decreased MRPL23-AS1 expression, whereas the rs217727 polymorphism was associated with increased MRPL23-AS1 expression. Overall, the H19 rs2839698, rs3024270 and rs217727 polymorphisms were associated with hepatoblastoma susceptibility in a Chinese Han population.

Modeling of Solid-Tumor Microenvironment in Zebrafish (Danio Rerio) Larvae.

The zebrafish larvae have emerged as a powerful model for studying tumorigenesis in vivo, with remarkable conservation with mammals in genetics, molecular and cell biology. Zebrafish tumor models bear the significant advantages of optical clarity in comparison to that in the mammalian models, allowing noninvasive investigation of the tumor cell and its microenvironment at single-cell resolution. Here we review recent progressions in the field of zebrafish models of solid tumor diseases in two main categories: the genetically engineered tumor models in which all cells in the tumor microenvironment are zebrafish cells, and xenograft tumor models in which the tumor microenvironment is composed of zebrafish cells and cells from other species. Notably, the zebrafish patient-derived xenograft (zPDX) models can be used for personalized drug assessment on primary tumor biopsies, including the pancreatic cancer. For the future studies, a series of high throughput drug screenings on the library of transgenic zebrafish models of solid tumor are expected to provide systematic database of oncogenic mutation, cell-of-origin, and leading compounds; and the humanization of zebrafish in genetics and cellular composition will make it more practical hosts for zPDX modeling. Together, zebrafish tumor model systems are unique and convenient in vivo platforms, with great potential to serve as valuable tools for cancer researches.

Association of CMYC polymorphisms with hepatoblastoma risk.

BACKGROUND: Single-nucleotide polymorphisms (SNPs) in genes may affect gene expression and contribute to cancer susceptibility. This study aimed to explore the association between CMYC gene polymorphisms and hepatoblastoma risk. METHODS: Hepatoblastoma patients and cancer-free controls were recruited and matched by age and sex. Genotypes were determined by TaqMan, and the strength of the association of interest was determined by calculating odds ratios (ORs) and 95% confidence intervals (CIs). The distributions of various CMYC genotypes among subjects were recorded, followed by analyses of associations between CMYC polymorphisms and hepatoblastoma risk. RESULTS: A total of 213 hepatoblastoma patients and 958 cancer-free controls were enrolled. No significant associations between the CMYC rs4645943 and rs2070583 polymorphisms and hepatoblastoma risk were found (all P>0.05). In stratification analysis based on age, sex, and clinical stage, the CMYC rs4645943 and rs2070583 polymorphisms were not associated with hepatoblastoma susceptibility (all P>0.05). CONCLUSIONS: Thus, the CMYC rs4645943 and rs2070583 polymorphisms were not associated with hepatoblastoma risk in the study cohort.

Associations of SLC6A20 genetic polymorphisms with Hirschsprung's disease in a Southern Chinese population.

Hirschsprung's disease (HSCR) is a neurodevelopmental disorder characterized by the absence of nerves in intestine with strong genetic components. SLC6A20 was found to be associated with HSCR in Korean population waiting for replication in an independent cohort. In the present study, ten single nucleotide polymorphisms (SNPs) in the SLC6A20 were selected from Southern Chinese with 1470 HSCR cases and 1473 ethnically matched healthy controls. Our results indicated that SNP rs7640009 was associated with HSCR and SLC6A20 has a gene-dose effect in the extent of the aganglionic segment during enteric nervous system (ENS) development. It is the first time to reveal the relationship between SNP rs2191026 and HSCR-associated enterocolitis (HAEC) susceptibility.

LINC00673 rs11655237 C>T Polymorphism Impacts Hepatoblastoma Susceptibility in Chinese Children.

BACKGROUND: Hepatoblastoma (HB) is the most common hepatic malignancy in children, accounting for approximately 80% of all childhood liver tumors. Previous genome-wide association studies (GWASs) have found that the LINC00673 rs11655237 C>T polymorphism is associated with the risk of several different adult cancers. However, the association between this polymorphism and HB susceptibility remains unclear. METHODS: We analyzed the association between the LINC00673 rs11655237 C>T polymorphism and HB susceptibility in a hospital-based study of Chinese children. We enrolled 213 HB patients and 958 healthy controls with genotypes determined by TaqMan, and the strength of the association of interest was determined by calculating odds ratios (ORs) and 95% confidence intervals (CIs). FINDINGS: We found a significant association between the LINC00673 rs11655237 C>T polymorphism and HB risk (CT/TT compared with CC: adjusted OR = 1.40, 95% CI = 1.04-1.88, p = 0.029). Furthermore, stratified analysis indicated that rs11655237 T allele carriers in the following subgroups were more likely to develop HB: children older than 17 months, males, and those with tumors of clinical stages III + IV. INTERPRETATION: In conclusion, we confirmed that the LINC00673 rs11655237 C>T polymorphism may be associated with HB susceptibility. Prospective studies with larger sample sizes and patients of different ethnicities are needed to validate our findings.

NRAS and KRAS polymorphisms are not associated with hepatoblastoma susceptibility in Chinese children.

BACKGROUND: Hepatoblastoma is the most common hepatic malignancy in children, accounting for approximately 80% of all childhood liver tumors. KRAS and NRAS, members of the RAS gene family, are closely linked to tumorigenesis, and are frequently mutated in a variety of malignancies. They may thus play critical roles in tumorigenesis. However, there are few studies on the association between the RAS gene polymorphisms and risk of hepatoblastoma. METHODS: We investigated whether the polymorphisms at these genes are associated with hepatoblastoma susceptibility in a hospital-based study of 213 affected Chinese children and 958 cancer-free controls. Genotypes were determined by TaqMan assay, and association with hepatoblastoma risk was assessed based on odds ratios and 95% confidence intervals. RESULTS: No significant differences were observed between patients and controls in terms of age and gender frequency. All NRAS and KRAS genotypes are in Hardy-Weinberg equilibrium in the entire study population. We did not observe any significant association between hepatoblastoma risk and polymorphisms at NRAS and KRAS. The association between selected polymorphisms and hepatoblastoma risk was assessed after stratification by age, gender, and clinical stage. However, no significant association was observed even after stratification by age, gender, and clinical stage. CONCLUSIONS: The data suggest that NRAS and KRAS polymorphisms are irrelevant to hepatoblastoma susceptibility among Chinese population.

Pleiotropic effect of common PHOX2B variants in Hirschsprung disease and neuroblastoma.

Hirschsprung disease (HSCR) is a heterogeneous congenital disorder that affects the enteric nervous system, while neuroblastoma is an embryonal tumor of the sympathetic nervous system. Familial cases of both HSCR and neuroblastoma appear to be functionally linked to PHOX2B, which plays a key role in the development of neural crest derivatives. However, the association between common PHOX2B variants and disease risk is contested. Additionally, large-scale examination for pleiotropy or shared genetic susceptibility in sporadic HSCR and neuroblastoma cases lacks theoretical support. Here, we report the first examination of PHOX2B in 1470 HSCR and 469 neuroblastoma patients with matched healthy controls. The PHOX2B rs28647582 polymorphism was found to be associated with HSCR (P = 2.21E-03, OR = 1.26), and each subtype of the ailment (3.22E-03 ≤ P ≤ 0.43, 1.11 ≤ OR ≤ 2.32). The association between rs28647582 and NB risk was consistent with HSCR in a recessive model, though the P value was marginal (P = 0.06). These new genetic findings indicate the potential pleiotropic effects of PHOX2B in both HSCR and neuroblastoma, which could guide the development of therapeutic targets for the treatment of related neurodevelopmental disorders.

Canonical Wnt Signaling Remodels Lipid Metabolism in Zebrafish Hepatocytes following Ras Oncogenic Insult.

There is limited understanding of the effects of major oncogenic pathways and their combinatorial actions on lipid composition and transformation during hepatic tumorigenesis. Here, we report a negative correlation of Wnt/Myc activity with steatosis in human hepatocellular carcinoma (HCC) and perform in vivo functional studies using three conditional transgenic zebrafish models. Double-transgenic zebrafish larvae conditionally expressing human CTNNB1mt and zebrafish tcf7l2 or murine Myc together with krasv12 in hepatocytes led to severe hepatomegaly and significantly attenuated accumulation of lipid droplets and cell senescence triggered by krasv12 expression alone. UPLC-MS-based, nontargeted lipidomic profiling and transcriptome analyses revealed that Wnt/Myc activity promotes triacylglycerol to phospholipid transformation and increases unsaturated fatty acyl groups in phospholipids in a Ras-dependent manner. Small-scale screenings suggested that supplementation of certain free fatty acids (FA) or inhibition of FA desaturation significantly represses hepatic hyperplasia of double-transgenic larvae and proliferation of three human HCC cells with and without sorafenib. Together, our studies reveal novel Ras-dependent functions of Wnt signaling in remodeling the lipid metabolism of cancerous hepatocytes in zebrafish and identify the SCD inhibitor MK8245 as a candidate drug for therapeutic intervention.Significance: These findings identify FA desaturation as a significant downstream therapeutic target for antagonizing the combinatorial effects of Wnt and Ras signaling pathways in hepatocellular carcinoma.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/19/5548/F1.large.jpg Cancer Res; 78(19); 5548-60. ©2018 AACR.

Association of VAMP5 and MCC genetic polymorphisms with increased risk of Hirschsprung disease susceptibility in Southern Chinese children.

Hirschsprung disease (HSCR) is a genetic disorder characterized by the absence of neural crest cells in parts of the intestine. This study aims to investigate the association of vesicle-associated membrane protein 5 (VAMP5) and mutated in colorectal cancer (MCC) genetic polymorphisms and their correlated risks with HSCR. We examined the association in four polymorphisms (rs10206961, rs1254900 and rs14242 in VAMP5, rs11241200 in MCC) and HSCR susceptibility in a Southern Chinese population composed of 1473 cases and 1469 controls. Two variants in VAMP5 were replicated as associated with HSCR. Interestingly, we clarified SNPs rs10206961 and rs1254900 in VAMP5 are more essential for patients with long-segment aganglionosis (LHSCR). Relatively high expression correlation was observed between VAMP5 and MCC using data from public database showing there may exist potential genetic interactions. SNP interaction was cross-examined by logistic regression and multifactor dimensionality reduction analysis revealing that VAMP5 rs1254900 and MCC rs11241200 were interacting significantly, thereby contributing to the risk of HSCR. The results suggest that significant associations of the rs10206961 and rs14242 in VAMP5 with an increased risk of HSCR in Southern Chinese, especially in LHSCR patients. This study provided new evidence of epistatic association of VAMP5 and MCC with increased risk of HSCR.

Screening in larval zebrafish reveals tissue-specific distribution of fifteen fluorescent compounds.

The zebrafish is a prominent vertebrate model for low-cost in vivo whole organism screening. In our recent screening of the distribution patterns of fluorescent compounds in live zebrafish larvae, fifteen compounds with tissue-specific distributions were identified. Several compounds were observed to accumulate in tissues where they were reported to induce side-effects, and compounds with similar structures tended to be enriched in the same tissues, with minor differences. In particular, we found three novel red fluorescent bone-staining dyes: purpurin, lucidin and 3-hydroxy-morindone; purpurin can effectively label bones in both larval and adult zebrafish, as well as in postnatal mice, without significantly affecting bone mass and density. Moreover, two structurally similar chemotherapeutic compounds, doxorubicin and epirubicin, were observed to have distinct distribution preferences in zebrafish. Epirubicin maintained a relatively higher concentration in the liver, and performed better in inhibiting hepatic hyperplasia caused by the over-expression of krasG12V In total, our study suggests that the transparent zebrafish larvae serve as valuable tools for identifying tissue-specific distributions of fluorescent compounds.

High Resolution Imaging of DNA Methylation Dynamics using a Zebrafish Reporter.

As one of the major epigenetic modifications, DNA methylation is constantly regulated during embryonic development, cell lineage commitment, and pathological processes. To facilitate real-time observation of DNA methylation, we generated a transgenic zebrafish reporter of DNA methylation (zebraRDM) via knockin of an mCherry-fused methyl-CpG binding domain (MBD) probe driven by the bactin2 promoter. The probe colocalized with heterochromatin, and its intensity was positively correlated with 5 mC immunostaining at a subcellular resolution in early embryos. Biochemical assays indicated that cells with stronger fluorescence maintained a higher level of DNA methylation, and time-lapse imaging at the blastula stage showed that the level of DNA methylation was transiently strengthened during mitosis. By crossing zebraRDM with other fluorescent transgenic lines, we demonstrate that the reporter can visually distinguish different cell lineages in organs like the heart. Our zebraRDM reporter therefore serves as a convenient and powerful tool for high-resolution investigation of methylation dynamics in live animals.

[Generation and phenotype analysis of zebrafish mutations of obesity-related genes lepr and mc4r].

Obesity has become a severe public health problem across the world, and seriously affects the health and life quality of human beings. Here we generated lepr and mc4r mutant zebrafish via the CRISPR/Cas9 technique, and performed morphological and functional characterizations of those mutants. We observed that there was no significant phenotypic difference between homozygous mutants and wild-type controls before 2.5 months post-fertilization (mpf). However, the adult lepr-/- and mc4r-/- individuals displayed increased food intake, heavier weight, and higher body fat percentage, the characteristics of obesity phenotypes. Blood glucose test showed that overfeeding induced significantly impaired glucose tolerance in adult lepr-/- and mc4r-/- zebrafish. Furthermore, we analyzed 76 energy metabolism-related transcripts in lepr-/- and mc4r-/- zebrafish livers by using real-time RT-PCR, and compared the results with the published microarray data of Lepob/ob mouse livers, and found that the changes in the expression of insulin/IGF signaling (IIS) pathway genes in lepr-/- zebrafish and Lepob/ob mouse were positively correlated, suggesting that the IIS pathway maintains functional conservation between zebrafish and mammals during the evolution of the obesity-regulating molecule network.