Disruption of the Na+/K+-ATPase-purinergic P2X7 receptor complex in microglia promotes stress-induced anxiety.

Na+/K+-ATPase (NKA) plays an important role in the central nervous system. However, little is known about its function in the microglia. Here, we found that NKAα1 forms a complex with the purinergic P2X7 receptor (P2X7R), an adenosine 5'-triphosphate (ATP)-gated ion channel, under physiological conditions. Chronic stress or treatment with lipopolysaccharide plus ATP decreased the membrane expression of NKAα1 in microglia, facilitated P2X7R function, and promoted microglia inflammatory activation via activation of the NLRP3 inflammasome. Accordingly, global deletion or conditional deletion of NKAα1 in microglia under chronic stress-induced aggravated anxiety-like behavior and neuronal hyperexcitability. DR5-12D, a monoclonal antibody that stabilizes membrane NKAα1, improved stress-induced anxiety-like behavior and ameliorated neuronal hyperexcitability and neurogenesis deficits in the ventral hippocampus of mice. Our results reveal that NKAα1 limits microglia inflammation and may provide a target for the treatment of stress-related neuroinflammation and diseases.

Prenatal dexamethasone exposure induces anxiety- and depressive-like behavior of male offspring rats through intrauterine programming of the activation of NRG1-ErbB4 signaling in hippocampal PV interneurons.

Dexamethasone is a commonly used synthetic glucocorticoid in the clinic. As a compound that can cross the placental barrier to promote fetal lung maturation, dexamethasone is extensively used in pregnant women at risk of premature delivery. However, the use of glucocorticoids during pregnancy increases the risk of neurodevelopmental disorders. In the present study, we observed anxiety- and depressive-like behavior changes and hyperexcitability of hippocampal neurons in adult rat offspring with previous prenatal dexamethasone exposure (PDE); the observed changes were related to in utero damage of parvalbumin interneurons. A programmed change in neuregulin 1 (NRG1)-Erb-b2 receptor tyrosine kinase 4 (ErbB4) signaling was the key to the damage of parvalbumin interneurons in the hippocampus of PDE offspring. Anxiety- and depressive-like behavior, NRG1-ErbB4 signaling activation, and damage of parvalbumin interneurons in PDE offspring were aggravated after chronic stress. The intervention of NRG1-ErbB4 signaling contributed to the improvement in dexamethasone-mediated injury to parvalbumin interneurons. These results suggested that PDE might cause anxiety- and depressive-like behavior changes in male rat offspring through the programmed activation of NRG1-ErbB4 signaling, resulting in damage to parvalbumin interneurons and hyperactivity of the hippocampus. Intrauterine programming of neuregulin 1 (NRG1)-Erb-b2 receptor tyrosine kinase 4 (ERBB4) overactivation by dexamethasone mediates anxiety- and depressive-like behavior in male rat offspring.

α-MSH-catabolic enzyme prolylcarboxypeptidase in nucleus accumbens shell ameliorates stress susceptibility in mice through regulating synaptic plasticity.

Emerging evidence demonstrates the vital role of synaptic transmission and structural remodeling in major depressive disorder. Activation of melanocortin receptors facilitates stress-induced emotional behavior. Prolylcarboxypeptidase (PRCP) is a serine protease, which splits the C-terminal amino acid of α-MSH and inactivates it. In this study, we asked whether PRCP, the endogenous enzyme of melanocortin system, might play a role in stress susceptibility via regulating synaptic adaptations. Mice were subjected to chronic social defeat stress (CSDS) or subthreshold social defeat stress (SSDS). Depressive-like behavior was assessed in SIT, SPT, TST and FST. Based on to behavioral assessments, mice were divided into the susceptible (SUS) and resilient (RES) groups. After social defeat stress, drug infusion or viral expression and behavioral tests, morphological and electrophysiological analysis were conducted in PFX-fixed and fresh brain slices containing the nucleus accumbens shell (NAcsh). We showed that PRCP was downregulated in NAcsh of susceptible mice. Administration of fluoxetine (20 mg·kg-1·d-1, i.p., for 2 weeks) ameliorated the depressive-like behavior, and restored the expression levels of PRCP in NAcsh of susceptible mice. Pharmacological or genetic inhibition of PRCP in NAcsh by microinjection of N-benzyloxycarbonyl-L-prolyl-L-prolinal (ZPP) or LV-shPRCP enhanced the excitatory synaptic transmission in NAcsh, facilitating stress susceptibility via central melanocortin receptors. On the contrary, overexpression of PRCP in NAcsh by microinjection of AAV-PRCP alleviated the depressive-like behavior and reversed the enhanced excitatory synaptic transmission, abnormal dendritogenesis and spinogenesis in NAcsh induced by chronic stress. Furthermore, chronic stress increased the level of CaMKIIα, a kinase closely related to synaptic plasticity, in NAcsh. The elevated level of CaMKIIα was reversed by overexpression of PRCP in NAcsh. Pharmacological inhibition of CaMKIIα in NAcsh alleviated stress susceptibility induced by PRCP knockdown. This study has revealed the essential role of PRCP in relieving stress susceptibility through melanocortin signaling-mediated synaptic plasticity in NAcsh.

Integrative analysis of genome-wide DNA methylation and gene expression profiles reveals important epigenetic genes related to milk production traits in dairy cattle.

Epigenetic modification plays a critical role in establishing and maintaining cell differentiation, embryo development, tumorigenesis and many complex diseases. However, little is known about the epigenetic regulatory mechanisms for milk production in dairy cattle. Here, we conducted an epigenome-wide study, together with gene expression profiles to identify important epigenetic candidate genes related to the milk production traits in dairy cattle. Whole-genome bisulphite sequencing and RNA sequencing were employed to detect differentially methylated genes (DMG) and differentially expressed genes (DEG) in blood samples in dry period and lactation period between two groups of cows with extremely high and low milk production performance. A total of 10,877 and 6,617 differentially methylated regions were identified between the two groups in the two periods, which corresponded to 3,601 and 2,802 DMGs, respectively. Furthermore, 156 DEGs overlap with DMGs in comparison of the two groups, and 131 DEGs overlap with DMGs in comparison of the two periods. By integrating methylome, transcriptome and GWAS data, some potential candidate genes for milk production traits in dairy cattle were suggested, such as DOCK1, PTK2 and PIK3R1. Our studies may contribute to a better understanding of epigenetic modification on milk production traits of dairy cattle.

Role of GPIHBP1 in regulating milk protein traits in dairy cattle.

Glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1) is among the many candidate genes for regulating milk production traits in dairy cattle that have been identified via quantitative trait locus (QTL) mapping and genome-wide association studies (GWAS). Our previous studies confirmed that a G-to-A mutation at chr14:2553998 is the main cause of GPIHBP1-related effects on milk fat content. In this study, we discovered that GPIHBP1 may be a strong candidate gene for the regulation of milk protein traits. We performed overexpression and RNAi experiments to assess GPIHBP1 in bovine primary mammary epithelial cells (BMECs) and identified mRNA expression patterns of several important milk protein-related genes using real-time quantitative PCR. After the transient transfection of BMECs with GPIHBP1, the transcription levels of casein genes (CSN1S1, CSN1S2, CSN2, and CSN3) and lactoferrin (LTF) decreased, whereas beta-lactoglobulin (LGB) expression increased. The GPIHBP1 RNAi experiment produced changes in gene expression that were completely opposite to those observed in the GPIHBP1 overexpression experiment. Furthermore, among the assessed genes, CSN3, LTF, and LGB exhibited significant changes in mRNA expression (p < 0.05). The findings of this study show that bovine GPIHBP1 is involved in the process of milk protein biosynthesis and may be considered as a functional gene for the milk protein yield trait.

Pharmacokinetics, bioavailability and metabolism of scopoletin in dog by ultra-high-performance liquid chromatography combined with linear ion trap-Orbitrap tandem mass spectrometry.

A highly sensitive and selective method based on ultra-high-performance liquid chromatography combined with linear ion trap-Orbitrap tandem mass spectrometry (UHPLC-LTQ-Orbitrap-MS) has been developed and validated for the determination of scopoletin in dog plasma. The analyte was extracted from plasma samples using acetonitrile and separated on an Acquity UPLC BEH C18 column (50 × 2.1 mm, 1.7 µm) with 0.05% ammonium hydroxide and acetonitrile as mobile phase. The developed method was linear over the concentration range of 1-500 ng/mL, with a correlation coefficient >0.9988. The intra- and inter-day precisions (RSD) were <8.93% while the accuracy (RE) ranged from -6.50 to 8.12%. Extraction recovery, matrix effect and stability for dog plasma samples were within the required limits. The validated method has been successfully applied to investigate the pharmacokinetics and metabolism of scopoletin in dog plasma after intravenous (1 mg/kg) and oral (10, 25, 50 mg/kg) administration. The results revealed that (a) scopoletin showed short elimination half-life in dog; (b) its oral bioavailability was low (within the range of 5.69-7.08%); (c) scopoletin showed dose-independent pharmacokinetic profiles in dog plasma over the dose range of 10-50 mg/kg; and (d) glucuronidation was the predominant metabolic pathway in dog.

Prenatal nicotine exposure induces HPA axis-hypersensitivity in offspring rats via the intrauterine programming of up-regulation of hippocampal GAD67.

The intrauterine programming of hypothalamic-pituitary-adrenal (HPA) axis hypersensitivity is associated with chronic adult diseases. Our previous studies demonstrated the HPA-axis hypersensitivity in offspring rats induced by prenatal nicotine exposure. The goal of the present study is to further investigate the intrauterine programming mechanism. Pregnant Wistar rats were subcutaneously administered with 2.0 mg/kg day of nicotine from gestational day (GD) 9-20. A group of the pregnant rats was euthanized at GD20, and the fetal rats were extracted. The remaining rats were left to come to term, and the adult offspring were exposed to chronic stress. For adult offspring rats, prenatal nicotine exposure induced HPA-axis hypersensitivity after chronic stress, accompanied by imbalanced glutamatergic/GABAergic afferent inputs. Moreover, prenatal nicotine exposure enhanced the expression of hippocampal glutamic acid decarboxylase 67 (GAD67), accompanied by a decreased methylation ratio within nt -1019 to -689 of the GAD67 promoter, decreased expression of Dnmt1, and an increased GABA content and density of GABAergic neurons. The fetal rats exhibited changes consistent with the adult rats. Similar effects were also observed by treating the fetal hippocampal cell line H19-7 with 1-100 µM nicotine, while dihydro-ß-erythroidine hydrobromide (DHßE), the specific inhibitor of α4ß2nAChR, can reverse the effects caused by nicotine. These results indicate that prenatal nicotine exposure can enhance the potential excitability of the hypothalamus via the intrauterine programming of up-regulation of hippocampal GAD67. All of these results contribute to the HPA-axis hypersensitivity in adult offspring.

Na+/K+-ATPase: ion pump, signal transducer, or cytoprotective protein, and novel biological functions.

Na+/K+-ATPase is a transmembrane protein that has important roles in the maintenance of electrochemical gradients across cell membranes by transporting three Na+ out of and two K+ into cells. Additionally, Na+/K+-ATPase participates in Ca2+-signaling transduction and neurotransmitter release by coordinating the ion concentration gradient across the cell membrane. Na+/K+-ATPase works synergistically with multiple ion channels in the cell membrane to form a dynamic network of ion homeostatic regulation and affects cellular communication by regulating chemical signals and the ion balance among different types of cells. Therefore, it is not surprising that Na+/K+-ATPase dysfunction has emerged as a risk factor for a variety of neurological diseases. However, published studies have so far only elucidated the important roles of Na+/K+-ATPase dysfunction in disease development, and we are lacking detailed mechanisms to clarify how Na+/K+-ATPase affects cell function. Our recent studies revealed that membrane loss of Na+/K+-ATPase is a key mechanism in many neurological disorders, particularly stroke and Parkinson's disease. Stabilization of plasma membrane Na+/K+-ATPase with an antibody is a novel strategy to treat these diseases. For this reason, Na+/K+-ATPase acts not only as a simple ion pump but also as a sensor/regulator or cytoprotective protein, participating in signal transduction such as neuronal autophagy and apoptosis, and glial cell migration. Thus, the present review attempts to summarize the novel biological functions of Na+/K+-ATPase and Na+/K+-ATPase-related pathogenesis. The potential for novel strategies to treat Na+/K+-ATPase-related brain diseases will also be discussed.

Characteristics of Vaginal Microbiota of Women of Reproductive Age with Infections.

The vaginal microbiota can be classified into five major community state types (CSTs) based on the bacterial content. However, the link between different CST subtypes and vaginal infection remains unclear. Here, we analyzed 2017 vaginal microbiota samples from women of a reproductive age with vaginal infections that were published in the last decade. We found that L. iners was the most dominant in 34.8% of the vaginal samples, followed by L. crispatus (21.2%). CST I was common in healthy individuals, whereas CST III and IV were associated with dysbiosis and infection. CST III-B, IV-A, IV-B, and IV-C0 were prevalent in patients with bacterial vaginosis (BV). Based on the relative abundance of bacteria at the (sub)genus level, a random forest classifier was developed to predict vaginal infections with an area under the curve of 0.83. We further identified four modules of co-occurring bacterial taxa: L. crispatus, Gardnerella, Prevotella, and Bacteroides. The functional prediction revealed that nucleotide biosynthesis pathways were upregulated in patients with human papilloma virus, and carbohydrate degradation pathways were downregulated in patients with BV. Overall, our study identified the bacterial signatures of healthy and infected vaginal microbiota, providing unique insights into the clinical diagnosis and health status prediction of women of a reproductive age.

An expanded database and analytical toolkit for identifying bacterial virulence factors and their associations with chronic diseases.

Virulence factor genes (VFGs) play pivotal roles in bacterial infections and have been identified within the human gut microbiota. However, their involvement in chronic diseases remains poorly understood. Here, we establish an expanded VFG database (VFDB 2.0) consisting of 62,332 nonredundant orthologues and alleles of VFGs using species-specific average nucleotide identity ( https://github.com/Wanting-Dong/MetaVF_toolkit/tree/main/databases ). We further develop the MetaVF toolkit, facilitating the precise identification of pathobiont-carried VFGs at the species level. A thorough characterization of VFGs for 5452 commensal isolates from healthy individuals reveals that only 11 of 301 species harbour these factors. Further analyses of VFGs within the gut microbiomes of nine chronic diseases reveal both common and disease-specific VFG features. Notably, in type 2 diabetes patients, long HiFi sequencing confirms that shared VF features are carried by pathobiont strains of Escherichia coli and Klebsiella pneumoniae. These findings underscore the critical importance of identifying and understanding VFGs in microbiome-associated diseases.

A thalamic circuit facilitates stress susceptibility via melanocortin 4 receptor-mediated activation of nucleus accumbens shell.

AIMS: Central melanocortin 4 receptor (MC4R) has been reported to induce anhedonia via eliciting dysfunction of excitatory synapses. It is evident that metabolic signals are closely related to chronic stress-induced depression. Here, we investigated that a neural circuit is involved in melanocortin signaling contributing to susceptibility to stress. METHODS: Chronic social defeat stress (CSDS) was used to develop depressive-like behavior. Electrophysiologic and chemogenetic approaches were performed to evaluate the role of paraventricular thalamus (PVT) glutamatergic to nucleus accumbens shell (NAcsh) circuit in stress susceptibility. Pharmacological and genetic manipulations were applied to investigate the molecular mechanisms of melanocortin signaling in the circuit. RESULTS: CSDS increases the excitatory neurotransmission in NAcsh through MC4R signaling. The enhanced excitatory synaptic input in NAcsh is projected from PVT glutamatergic neurons. Moreover, chemogenetic manipulation of PVTGlu -NAcsh projection mediates the susceptibility to stress, which is dependent on MC4R signaling. Overall, these results reveal that the strengthened excitatory neurotransmission in NAcsh originates from PVT glutamatergic neurons, facilitating the susceptibility to stress through melanocortin signaling. CONCLUSIONS: Our results make a strong case for harnessing a thalamic circuit to reorganize excitatory synaptic transmission in relieving stress susceptibility and provide insights gained on metabolic underpinnings of protection against stress-induced depressive-like behavior.

Mitochondrial fission drives neuronal metabolic burden to promote stress susceptibility in male mice.

Neurons are particularly susceptible to energy fluctuations in response to stress. Mitochondrial fission is highly regulated to generate ATP via oxidative phosphorylation; however, the role of a regulator of mitochondrial fission in neuronal energy metabolism and synaptic efficacy under chronic stress remains elusive. Here, we show that chronic stress promotes mitochondrial fission in the medial prefrontal cortex via activating dynamin-related protein 1 (Drp1), resulting in mitochondrial dysfunction in male mice. Both pharmacological inhibition and genetic reduction of Drp1 ameliorates the deficit of excitatory synaptic transmission and stress-related depressive-like behavior. In addition, enhancing Drp1 fission promotes stress susceptibility, which is alleviated by coenzyme Q10, which potentiates mitochondrial ATP production. Together, our findings unmask the role of Drp1-dependent mitochondrial fission in the deficits of neuronal metabolic burden and depressive-like behavior and provides medication basis for metabolism-related emotional disorders.

Realization of Single-Crystal Dye Lasers by Taming Charge Transfer in Molecular Self-Assemblies.

The large library of organic dye molecules offers almost infinite possibilities for laser design, but still faces a great challenge in achieving pure dye aggregate lasers due to intermolecular quenching. Here, we report a kinetically controlled molecular self-assembly strategy to synthesize unconventional dye microcrystals for lasing. By increasing temperature, the dye self-assembly is transformed from thermodynamic to kinetic control. Unlike the thermodynamic microcrystal products incapable of lasing due to intermolecular charge-transfer-mediated excimer formation, the kinetic dye microcrystals have large intermolecular distances and weak intermolecular interactions, supporting highly efficient intramolecular charge-transfer monomer emission and low-threshold lasing. This work demonstrates single-crystal dye lasers, promising to unleash the full potential of laser dyes in solid-state lasers.

Plant Cell Wall Breakdown by Hindgut Microorganisms: Can We Get Scientific Insights From Rumen Microorganisms?

Equines and ruminants have evolved as grazing herbivores with specialized gastrointestinal tracts capable of utilizing a wide range of fibrous feeds. In China, agricultural by-products, including corn straw, wheat straw, peanut vine, wheat husk, rice husk, and grass hay, have been extensively included in both equine and ruminant diets. These plant materials, which are composed predominantly of cellulose, hemicellulose, noncellulosic polysaccharides, and lignin, are largely undegradable by equines and ruminants themselves. Their breakdown is accomplished by communities of resident microorganisms that live in symbiotic or mutualistic associations with the host. Information relating to microbial composition in the hindgut and rumen has become increasingly available. Rumen fermentation is unique in that plant cell wall breakdown relies on the cooperation between microorganisms that produce fibrolytic enzymes and that ruminant animals provide an anaerobic fermentation chamber. Similar to the rumen, the equine hindgut is also an immensely enlarged fermentative chamber that includes an extremely abundant and highly complex community of microorganisms. However, few studies have characterized the microbial functions and their utilization process of lignocellulosic feeds within the equine hindgut. The process of understanding and describing plant cell wall degradation mechanisms in the equine hindgut ecosystem is important for providing information for proper feeding practices to be implemented. In the present study, we gather existing information on the rumen and equine ecosystem and provide scientific insights for understanding the process of plant cell wall breakdown within the hindgut.

Alterations of Suckling Piglet Jejunal Microbiota Due to Infection With Porcine Epidemic Diarrhea Virus and Protection Against Infection by Lactobacillus salivarius.

The high mortality of neonatal piglets due to porcine epidemic diarrhea virus (PEDV) infection has caused huge economic losses to the pig industry. The intestinal microbiota is an important barrier against invaders entering the gastrointestinal route. In this study, we examined the differences between intestinal microbiota of PEDV-infected and healthy piglets. According to the viral copy numbers, 16 crossbred (Landrace-Yorkshire) piglets were divided into three groups: uninfected, low virus load, and high virus load groups. Next, 16S rRNA sequencing was performed to determine the microbiota composition in jejunal content and jejunal mucosal samples from the three groups. PEDV infection induced an imbalance in the microbiota of both jejunal content and jejunal mucosa. The abundance of phylum Firmicutes was higher in uninfected piglets than in infected piglets, whereas the abundance of Proteobacteria was lower in uninfected piglets. Principal coordinate analysis showed significant separation of jejunal microbiota between different groups. Linear discriminant analysis (LDA) effect size (LEfSe) identified Lactobacillus salivarius as a potential biomarker among three groups at the level of species. Then, in vitro, L. salivarius was able to suppress the infection of PEDV to IPEC-J2 cells and decreased the expression of GRP78 (Glucose-regulating protein 78). In addition, we detected the mRNA expression of genes involved in the FAK/PI3K/Akt signaling pathway. When IPEC-J2 cells were treated with L. salivarius before PEDV infection, the mRNA expression levels of ITGA1, ITGA5, ITGB5, FAK, PIK3R1, PIK3CA and AKT1 were significantly higher than those in the control cells (without treatment) at different times post-infection, indicating that L. salivarius may upregulate the FAK/PI3K/Akt signaling pathway in IPEC-J2 cells to resist PEDV infection. In summary, PEDV infection altered microbial communities in both jejunal content and jejunal mucosa. L. salivarius has a protective effect against PEDV infection in IPEC-J2 cells. This study provides a potentially effective strategy to prevent the occurrence and control the spread of PED in the pig production.

Excitotoxicity and compensatory upregulation of GAD67 in fetal rat hippocampus caused by prenatal nicotine exposure are associated with inhibition of the BDNF pathway.

Prenatal nicotine exposure (PNE) can cause hypersensitivity of hypothalamic-pituitary-adrenal (HPA) axis in offspring with intrauterine growth retardation. The purpose of this study was to explore the original mechanism of intrauterine development that mediates hypersensitivity of the HPA axis in offspring due to PNE. Pregnant Wistar rats were injected subcutaneously with 2 mg/kg·d of nicotine on the 9th to the 20th gestational day (GD9-GD20) and the fetuses were extracted at GD20. Compared with the control group, fetal rats by PNE showed increased hippocampal apoptosis, reduced synaptic plasticity and downregulation of the brain-derived neurotrophic factor (BDNF) pathway, whereas glutamic acid decarboxylase 67 (GAD67) expression was upregulated. Rat fetal hippocampal H19-7/IGF1R cell lines were treated with different concentrations of nicotine (1, 10 and 100 µM) for 3 days, the extracellular fluid glutamate (Glu) level increased and similar effects were observed as in vivo. Intervention treatments caused the opposite results. These results indicated that PNE downregulates the BDNF pathway and mediates the hippocampal excitotoxicity; then, the compensatory upregulation of GAD67 causes the imbalance of signal output in the fetal hippocampus. The negative feedback regulation of the paraventricular hypothalamic nucleus by the hippocampus is unbalanced, eventually causing hypersensitivity of the HPA axis of the offspring.

Porcine Epidemic Diarrhea Altered Colonic Microbiota Communities in Suckling Piglets.

Porcine epidemic diarrhea (PED) is a major gastrointestinal disease afflicting suckling pigs that causes huge industrial economic losses. In this study, we investigated microbiota from the colonic mucosa and content in healthy and PED piglets. High-throughput 16S rRNA gene sequencing was performed to identify inter-group differences. Firmicutes, Fusobacteria, Proteobacteria, and Bacteroidetes were the top four affected phyla. The proportion of Proteobacteria was higher in infected than in healthy piglets, and the opposite was observed for Bacteroidetes (more than four-fold higher in the healthy group). In the infected group, Fusobacterium accounted for 36.56% and 21.61% in the colonic mucosa and contents, respectively, while in the healthy group, they comprised 22.53% and 12.67%, respectively. The percentage of Lactobacillus in healthy colons (15.63%) was considerably higher than that in the disease group (<10%). In both the colonic mucosa and contents, functional enrichment differed significantly between healthy and diseased groups. Overall, infection with the PED virus increased the proportion of harmful bacteria and decreased the proportion of beneficial bacteria in the colons of piglets. Targeting intestinal microbiota could be a promising method for PED prevention, thus opening new avenues for future research.

Changes in cecal microbiota community of suckling piglets infected with porcine epidemic diarrhea virus.

Diarrhea, caused by porcine epidemic diarrhea virus (PEDV), is a catastrophic gastrointestinal disease among suckling piglets, with high infectivity, morbidity, and mortality, causing huge economic losses to the pig industry. In the present study, we investigated the different microbiota from the cecal mucosa and cecal contents between healthy and PEDV-infected piglets. High-throughput 16S rRNA gene sequencing was performed to explore differences. The results revealed that microbial dysbiosis by PEDV infection occurred in the cecal mucosa and contents of suckling piglets at each microbial taxonomic level. The abundance of pathogenic bacteria associated with diseases, including diarrhea, was increased. The abundance of Fusobacterium was 26.71% and 33.91% in cecal mucosa and contents of PEDV-infected group, respectively, whereas that in the healthy groups was 17.85% and 9.88%. The proportion of Proteobacteria in the infected groups was relatively high (24.67% and 22.79%, respectively), whereas that in the healthy group was 13.13% and 11.34% in the cecal mucosa and contents, respectively. Additionally, the proportion of Bacteroidetes in the healthy group (29.89%, 37.32%) was approximately twice that of the PEDV-infected group (15.50%, 15.39%). "Nitrate reduction", "Human pathogens diarrhea", "Human pathogens gastroenteritis", "Nitrite respiration", and "Nitrite ammonification" were the enriched functional annotation terms in the PEDV-infected groups. Porcine epidemic diarrhea virus infection increased the proportion of harmful bacteria and decreased the proportion of beneficial bacteria in the cecal mucosa and contents of suckling piglets. Our findings suggest that determining the intestinal microbiota might provide a promising method to prevent PEDV and open a new avenue for future research.

Prenatal Dexamethasone Exposure Induced Alterations in Neurobehavior and Hippocampal Glutamatergic System Balance in Female Rat Offspring.

Epidemiological investigations have suggested that periodic use of dexamethasone during pregnancy is a risk factor for abnormal behavior in offspring, but the potential mechanism remains unclear. In this study, we investigated the changes in the glutamatergic system and neurobehavior in female offspring with prenatal dexamethasone exposure (PDE) to explore intrauterine programing mechanisms. Compared with the control group, rat offspring with PDE exhibited spatial memory deficits and anxiety-like behavior. The expression of hippocampal glucocorticoid receptors (GR) and histone deacetylase 2 (HDAC2) increased, whereas histone H3 lysine 14 acetylation (H3K14ac) of brain-derived neurotrophic factor (BDNF) exon IV (BDNF IV) and expression of BDNF decreased. The glutamatergic system also changed. We further observed that changes in the fetal hippocampus were consistent with those in adult offspring. In vitro, the administration of 0.5 µM dexamethasone to the H19-7 fetal hippocampal neuron cells directly led to a cascade of changes in the GR/HDAC2/BDNF pathway, whereas the GR antagonist RU486 and the HDAC2 inhibitor romidepsin (Rom) reversed changes caused by dexamethasone to the H3K14ac level of BDNF IV and to the expression of BDNF. The increase in HDAC2 can be reversed by RU486, and the changes in the glutamatergic system can be partially reversed after supplementation with BDNF. It is suggested that PDE increases the expression of HDAC2 by activating GR, reducing the H3K14ac level of BDNF IV, inducing alterations in neurobehavior and hippocampal glutamatergic system balance. The findings suggest that BDNF supplementation and glutamatergic system improvement are potential therapeutic targets for the fetal origins of abnormal neurobehavior.