Arginine methyltransferases PRMT2 and PRMT3 are essential for biosynthesis of plant-polysaccharide-degrading enzymes in Penicillium oxalicum.

Many filamentous fungi produce plant-polysaccharide-degrading enzymes (PPDE); however, the regulatory mechanism of this process is poorly understood. A Gal4-like transcription factor, CxrA, is essential for mycelial growth and PPDE production in Penicillium oxalicum. Its N-terminal region, CxrAΔ207-733 is required for the regulatory functions of whole CxrA, and contains a DNA-binding domain (CxrAΔ1-16&Δ59-733) and a methylated arginine (R) 94. Methylation of R94 is mediated by an arginine N-methyltransferase, PRMT2 and appears to induce dimerization of CxrAΔ1-60. Overexpression of prmt2 in P. oxalicum increases PPDE production by 41.4-95.1% during growth on Avicel, compared with the background strain Δku70;hphR+. Another arginine N-methyltransferase, PRMT3, appears to assist entry of CxrA into the nucleus, and interacts with CxrAΔ1-60 in vitro under Avicel induction. Deletion of prmt3 resulted in 67.0-149.7% enhanced PPDE production by P. oxalicum. These findings provide novel insights into the regulatory mechanism of fungal PPDE production.

Metabolic profiling identifies Qrich2 as a novel glutamine sensor that regulates microtubule glutamylation and mitochondrial function in mouse sperm.

In our prior investigation, we discerned loss-of-function variants within the gene encoding glutamine-rich protein 2 (QRICH2) in two consanguineous families, leading to various morphological abnormalities in sperm flagella and male infertility. The Qrich2 knockout (KO) in mice also exhibits multiple morphological abnormalities of the flagella (MMAF) phenotype with a significantly decreased sperm motility. However, how ORICH2 regulates the formation of sperm flagella remains unclear. Abnormal glutamylation levels of tubulin cause dysplastic microtubules and flagella, eventually resulting in the decline of sperm motility and male infertility. In the current study, by further analyzing the Qrich2 KO mouse sperm, we found a reduced glutamylation level and instability of tubulin in Qrich2 KO mouse sperm flagella. In addition, we found that the amino acid metabolism was dysregulated in both testes and sperm, leading to the accumulated glutamine (Gln) and reduced glutamate (Glu) concentrations, and disorderly expressed genes responsible for Gln/Glu metabolism. Interestingly, mice fed with diets devoid of Gln/Glu phenocopied the Qrich2 KO mice. Furthermore, we identified several mitochondrial marker proteins that could not be correctly localized in sperm flagella, which might be responsible for the reduced mitochondrial function contributing to the reduced sperm motility in Qrich2 KO mice. Our study reveals a crucial role of a normal Gln/Glu metabolism in maintaining the structural stability of the microtubules in sperm flagella by regulating the glutamylation levels of the tubulin and identifies Qrich2 as a possible novel Gln sensor that regulates microtubule glutamylation and mitochondrial function in mouse sperm.

Genotype of dengue virus serotype 1 in relation to severe dengue in Guangzhou, China.

Guangzhou has been the city most affected by the dengue virus (DENV) in China, with a predominance of DENV serotype 1 (DENV-1). Viral factors such as dengue serotype and genotype are associated with severe dengue (SD). However, none of the studies have investigated the relationship between DENV-1 genotypes and SD. To understand the association between DENV-1 genotypes and SD, the clinical manifestations of patients infected with different genotypes were investigated. A total of 122 patients with confirmed DENV-1 genotype infection were recruited for this study. The clinical manifestations, laboratory tests, and levels of inflammatory mediator factors were statistically analyzed to investigate the characteristics of clinical manifestations and immune response on the DENV-1 genotype. In the case of DENV-1 infection, the incidence of SD with genotype V infection was significantly higher than that with genotype I infection. Meanwhile, patients infected with genotype V were more common in ostealgia and bleeding significantly. In addition, levels of inflammatory mediator factors including IFN-γ, TNF-α, IL-10, and soluble vascular cell adhesion molecule 1 were higher in patients with SD infected with genotype V. Meanwhile, the concentrations of regulated upon activation normal T-cell expressed and secreted and growth-related gene alpha were lower in patients with SD infected with genotype V. The higher incidence of SD in patients infected with DENV-1 genotype V may be attributed to elevated cytokines and adhesion molecules, along with decreased chemokines.

Dengue encephalopathy in an adult due to dengue virus type 1 infection.

BACKGROUND: Dengue is an important public health problem, which caused by the dengue virus (DENV), a single-stranded RNA virus consisted of four serotypes. Central nervus system (CNS) impairment in dengue usually results from DENV-2 or DENV-3 infection, which lead to life-threatening outcomes. Furthermore, neurological complications due to DENV-1 was rare especially in adult patients. CASE PRESENTATION: A 44-year-old man without comorbidities had lethargy after hyperpyrexia and a positive DENV NS1 antigen was detected for confirming the diagnosis of dengue on day 8 of onset. Then logagnosia, decreased muscle strength, delirium and irritability were occurred even radiographic examination were normal. He was treated with low-dose hormone, sedatives and gamma goblin with a short duration of 6 days. The cerebrospinal fluid (CSF) tests were persistent normal. However, presence of DENV-1 RNA was confirmed both in CSF and serum. Furthermore, the complete sequence of the DENV isolated from the patient's serum was performed (GenBank No.: MW261838). The cytokines as IL-6, IL-10 and sVCAM-1 were increased in critical phase of disease. Finally, the patient was discharged on day 24 of onset without any neurological sequelae. CONCLUSION: Encephalopathy caused by a direct CNS invasion due to DENV-1 during viremia was described in an adult patient. Treatment with low-dose hormone and gamma goblin was helpful for admission.

Fanconi Anemia Complementary Group A (FANCA) Facilitates the Occurrence and Progression of Liver Hepatocellular Carcinoma.

BACKGROUND: Liver hepatocellular carcinoma (LIHC) is a serious liver disease worldwide, and its pathogenesis is complicated. AIMS: This study investigated the potential role of FANCA in the advancement and prognosis of LIHC. METHODS: Public databases, quantitative reverse transcription polymerase chain reaction (qRT-PCR), western blot (WB) and immunohistochemistry (IHC) were employed to measure FANCA expression between tumor and normal samples. The relationship between FANCA expression and prognosis of LIHC patients were examined. Functional enrichment of FANCA-related genes was performed. Furthermore, univariate and multivariate analyses were conducted to determine the independent prognosis value of FANCA in LIHC. Finally, influence of FANCA knockout on the proliferation, migration, and invasion of HepG2 cell was validated with cloning formation, CCK8, and Transwell assays. RESULTS: Expression analysis presented that FANCA had high expression level in LIHC tissues and cells. Receiver operating characteristic (ROC) curve analysis showed that FANCA was of great diagnosis value in LIHC. Clinicopathological analysis revealed that FANCA was significantly greater expressed in the advanced stage than in the early stage of LIHC. Univariate, multivariate, and Kaplan-Meier survival analysis confirmed that high expression of FANCA was strongly associated with poor survival of LIHC patients. In addition, high level of FANCA in LIHC showed a negative association with immunoinfiltrated B cells, T cells, and stromal scores. Moreover, Knockout of FANCA significantly inhibited HepG2 cell proliferative activity, migration, and invasion ability. CONCLUSIONS: Our data revealed that high level of FANCA was closely associated with LIHC malignant progression, suggesting its potential utility as a diagnostic, predictive indicator, and therapeutic target.

A Four Amino Acid Metabolism-Associated Genes (AMGs) Signature for Predicting Overall Survival Outcomes and Immunotherapeutic Efficacy in Hepatocellular Carcinoma.

Metabolites are important indicators of cancer and mutations in genes involved in amino acid metabolism may influence tumorigenesis. Immunotherapy is an effective cancer treatment option; however, its relationship with amino acid metabolism has not been reported. In this study, RNA-seq data for 371 liver cancer patients were acquired from TCGA and used as the training set. Data for 231 liver cancer patients were obtained from ICGC and used as the validation set to establish a gene signature for predicting liver cancer overall survival outcomes and immunotherapeutic responses. Four reliable groups based on 132 amino acid metabolism-related DEGs were obtained by consistent clustering of 371 HCC patients and a four-gene signature for prediction of liver cancer survival outcomes was developed. Our data show that in different clinical groups, the overall survival outcomes in the high-risk group were markedly low relative to the low-risk group. Univariate and multivariate analyses revealed that the characteristics of the 4-gene signature were independent prognostic factors for liver cancer. The ROC curve revealed that the risk characteristic is an efficient predictor for 1-, 2-, and 3-year HCC survival outcomes. The GSVA and KEGG pathway analyses revealed that high-risk score tumors were associated with all aspects of the degree of malignancy in liver cancer. There were more mutant genes and greater immune infiltrations in the high-risk groups. Assessment of the three immunotherapeutic cohorts established that low-risk score patients significantly benefited from immunotherapy. Then, we established a prognostic nomogram based on the TCGA cohort. In conclusion, the 4-gene signature is a reliable diagnostic marker and predictor for immunotherapeutic efficacy.

PoxCbh, a novel CENPB-type HTH domain protein, regulates cellulase and xylanase gene expression in Penicillium oxalicum.

The essential transcription factor PoxCxrA is required for cellulase and xylanase gene expression in the filamentous fungus Penicillium oxalicum that is potentially applied in biotechnological industry as a result of the existence of the integrated cellulolytic and xylolytic system. However, the regulatory mechanism of cellulase and xylanase gene expression specifically associated with PoxCxrA regulation in fungi is poorly understood. In this study, the novel regulator PoxCbh (POX06865), containing a centromere protein B-type helix-turn-helix domain, was identified through screening for the PoxCxrA regulon under Avicel induction and genetic analysis. The mutant ∆PoxCbh showed significant reduction in cellulase and xylanase production, ranging from 28.4% to 59.8%. Furthermore, PoxCbh was found to directly regulate the expression of important cellulase and xylanase genes, as well as the known regulatory genes PoxNsdD and POX02484, and its expression was directly controlled by PoxCxrA. The PoxCbh-binding DNA sequence in the promoter region of the cellobiohydrolase 1 gene cbh1 was identified. These results expand our understanding of the diverse roles of centromere protein B-like protein, the regulatory network of cellulase and xylanase gene expression, and regulatory mechanisms in fungi.

G protein γ subunit modulates expression of plant-biomass-degrading enzyme genes and mycelial-development-related genes in Penicillium oxalicum.

Heterotrimeric-G-protein-mediated signaling pathways modulate the expression of the essential genes in many fundamental cellular processes in fungi at the transcription level. However, these processes remain unclear in Penicillium oxalicum. In this study, we generated knockout and knockout-complemented strains of gng-1 (POX07071) encoding the Gγ protein and found that GNG-1 modulated the expression of genes encoding plant-biomass-degrading enzymes (PBDEs) and sporulation-related activators. Interestingly, GNG-1 affected expression of the cxrB that encodes a known transcription factor required for the expression of major cellulase and xylanase genes. Constitutive overexpression of cxrB in ∆gng-1 circumvented the dependence of PBDE production on GNG-1. Further evidence indicated that CxrB indirectly regulated the transcription levels of key amylase genes by controlling the expression of the regulatory gene amyR. These data extended the diversity of Gγ protein functions and provided new insight into the signal transduction and regulation of PBDE gene expression in filamentous fungi. KEY POINTS: • GNG-1 modulates the expression of PBDE genes and sporulation-related genes. • GNG-1 controls expression of the key regulatory gene cxrB. • Overexpression of cxrB circumvents dependence of PBDE production on GNG-1.

Involvement of phospholipase PLA2 in production of cellulase and xylanase by Penicillium oxalicum.

Phospholipases play vital roles in immune and inflammatory responses in mammals and plants; however, knowledge of phospholipase functions in fungi is limited. In this study, we investigated the effects of deleting predicted phospholipase genes on cellulase and xylanase production, and morphological phenotype, in Penicillium oxalicum. Individual deletion of nine of the ten predicted phospholipase genes resulted in alteration of cellulase and xylanase production, and the morphological phenotypes, to various degrees. The mutant ∆POX07277 lost 22.5 to 82.8% of cellulase (i.e., filter paper cellulase, carboxymethylcellulase, and p-nitrophenyl-ß-cellobiosidase) and xylanase production, whereas p-nitrophenyl-ß-glucopyranosidase production increased by 5.8-127.8 fold. POX07277 (P. oxalicum gene No. 07277) was predicted to encode phospholipase A2 and was found to negatively affect the sporulation of P. oxalicum. Comparative transcriptomic and quantitative reverse transcription-PCR analysis indicated that POX07277 dynamically affected the expression of cellulase and xylanase genes and the regulatory genes for fungal sporulation, under micro-crystalline cellulose induction. POX07277 was required for the expression of the known regulatory gene PoxCxrB (cellulolytic and xylanolytic regulator B in P. oxalicum), which is involved in cellulase and xylanase gene expression in P. oxalicum. Conversely, POX07277 expression was regulated by PoxCxrB. These findings will aid the understanding of phospholipase functions and provide novel insights into the mechanism of fungal cellulase and xylanase gene expression. KEY POINTS : • The roles of phospholipases were investigated in Penicillium oxalicum. • POX07277 (PLA2) is required for the expression of cellulase and xylanase genes. • PoxCxrB dynamically regulated POX07277 expression.

PAQR3 controls autophagy by integrating AMPK signaling to enhance ATG14L-associated PI3K activity.

The Beclin1-VPS34 complex is recognized as a central node in regulating autophagy via interacting with diverse molecules such as ATG14L for autophagy initiation and UVRAG for autophagosome maturation. However, the underlying molecular mechanism that coordinates the timely activation of VPS34 complex is poorly understood. Here, we identify that PAQR3 governs the preferential formation and activation of ATG14L-linked VPS34 complex for autophagy initiation via two levels of regulation. Firstly, PAQR3 functions as a scaffold protein that facilitates the formation of ATG14L- but not UVRAG-linked VPS34 complex, leading to elevated capacity of PI(3)P generation ahead of starvation signals. Secondly, AMPK phosphorylates PAQR3 at threonine 32 and switches on PI(3)P production to initiate autophagosome formation swiftly after glucose starvation. Deletion of PAQR3 leads to reduction of exercise-induced autophagy in mice, accompanied by a certain degree of disaggregation of ATG14L-associated VPS34 complex. Together, this study uncovers that PAQR3 can not only enhance the capacity of pro-autophagy class III PI3K due to its scaffold function, but also integrate AMPK signal to activation of ATG14L-linked VPS34 complex upon glucose starvation.

Transcription Factor Atf1 Regulates Expression of Cellulase and Xylanase Genes during Solid-State Fermentation of Ascomycetes.

Transcriptional regulation of cellulolytic and xylolytic genes in ascomycete fungi is controlled by specific carbon sources in different external environments. Here, comparative transcriptomic analyses of Penicillium oxalicum grown on wheat bran (WB), WB plus rice straw (WR), or WB plus Avicel (WA) as the sole carbon source under solid-state fermentation (SSF) revealed that most of the differentially expressed genes (DEGs) were involved in metabolism, specifically, carbohydrate metabolism. Of the DEGs, the basic core carbohydrate-active enzyme-encoding genes which responded to the plant biomass resources were identified in P. oxalicum, and their transcriptional levels changed to various extents depending on the different carbon sources. Moreover, this study found that three deletion mutants of genes encoding putative transcription factors showed significant alterations in filter paper cellulase production compared with that of a parental P. oxalicum strain with a deletion of Ku70 (ΔPoxKu70 strain) when grown on WR under SSF. Importantly, the ΔPoxAtf1 mutant (with a deletion of P. oxalicumAtf1, also called POX03016) displayed 46.1 to 183.2% more cellulase and xylanase production than a ΔPoxKu70 mutant after 2 days of growth on WR. RNA sequencing and quantitative reverse transcription-PCR revealed that PoxAtf1 dynamically regulated the expression of major cellulase and xylanase genes under SSF. PoxAtf1 bound to the promoter regions of the key cellulase and xylanase genes in vitro This study provides novel insights into the regulatory mechanism of fungal cellulase and xylanase gene expression under SSF.IMPORTANCE The transition to a more environmentally friendly economy encourages studies involving the high-value-added utilization of lignocellulosic biomass. Solid-state fermentation (SSF), that simulates the natural habitat of soil microorganisms, is used for a variety of applications such as biomass biorefinery. Prior to the current study, our understanding of genome-wide gene expression and of the regulation of gene expression of lignocellulose-degrading enzymes in ascomycete fungi during SSF was limited. Here, we employed RNA sequencing and genetic analyses to investigate transcriptomes of Penicillium oxalicum strain EU2101 cultured on medium containing different carbon sources and to identify and characterize transcription factors for regulating the expression of cellulase and xylanase genes during SSF. The results generated will provide novel insights into genetic engineering of filamentous fungi to further increase enzyme production.

Transcription Factor NsdD Regulates the Expression of Genes Involved in Plant Biomass-Degrading Enzymes, Conidiation, and Pigment Biosynthesis in Penicillium oxalicum.

Soil fungi produce a wide range of chemical compounds and enzymes with potential for applications in medicine and biotechnology. Cellular processes in soil fungi are highly dependent on the regulation under environmentally induced stress, but most of the underlying mechanisms remain unclear. Previous work identified a key GATA-type transcription factor, Penicillium oxalicum NsdD (PoxNsdD; also called POX08415), that regulates the expression of cellulase and xylanase genes in P. oxalicum PoxNsdD shares 57 to 64% identity with the key activator NsdD, involved in asexual development in Aspergillus In the present study, the regulatory roles of PoxNsdD in P. oxalicum were further explored. Comparative transcriptomic profiling revealed that PoxNsdD regulates major genes involved in starch, cellulose, and hemicellulose degradation, as well as conidiation and pigment biosynthesis. Subsequent experiments confirmed that a ΔPoxNsdD strain lost 43.9 to 78.8% of starch-digesting enzyme activity when grown on soluble corn starch, and it produced 54.9 to 146.0% more conidia than the ΔPoxKu70 parental strain. During cultivation, ΔPoxNsdD cultures changed color, from pale orange to brick red, while the ΔPoxKu70 cultures remained bluish white. Real-time quantitative reverse transcription-PCR showed that PoxNsdD dynamically regulated the expression of a glucoamylase gene (POX01356/Amy15A), an α-amylase gene (POX09352/Amy13A), and a regulatory gene (POX03890/amyR), as well as a polyketide synthase gene (POX01430/alb1/wA) for yellow pigment biosynthesis and a conidiation-regulated gene (POX06534/brlA). Moreover, in vitro binding experiments showed that PoxNsdD bound the promoter regions of the above-described genes. This work provides novel insights into the regulatory mechanisms of fungal cellular processes and may assist in genetic engineering of Poxalicum for potential industrial and medical applications.IMPORTANCE Most filamentous fungi produce a vast number of extracellular enzymes that are used commercially for biorefineries of plant biomass to produce biofuels and value-added chemicals, which might promote the transition to a more environmentally friendly economy. The expression of these extracellular enzyme genes is tightly controlled at the transcriptional level, which limits their yields. Hitherto our understanding of the regulation of expression of plant biomass-degrading enzyme genes in filamentous fungi has been rather limited. In the present study, regulatory roles of a key regulator, PoxNsdD, were further explored in the soil fungus Penicillium oxalicum, contributing to the understanding of gene regulation in filamentous fungi and revealing the biotechnological potential of Poxalicum via genetic engineering.

Characterization of novel roles of a HMG-box protein PoxHmbB in biomass-degrading enzyme production by Penicillium oxalicum.

High-mobility group (HMG)-box proteins are involved in chromatin organization in eukaryotes, especially in sex determination and regulation of mitochondrial DNA compaction. Although a novel HMG-box protein, PoxHmbB, had been initially identified to be required for filter paper cellulase activity by Penicillium oxalicum, the biological roles of HMG-box proteins in biomass-degrading enzyme production have not been systematically explored. The P. oxalicum mutant ∆PoxHmbB lost 34.7-86.5% of cellulase (endoglucanase, p-nitrophenyl-ß-cellobiosidase, and p-nitrophenyl-ß-glucopyranosidase) activities and 60.3% of xylanase activity following Avicel induction, whereas it exhibited about onefold increase in amylase activity following soluble corn starch induction. Furthermore, ∆PoxHmbB presented delayed conidiation and hyphae growth. Transcriptomic profiling and real-time quantitative reverse transcription-PCR revealed that PoxHmbB regulated the expression of major genes encoding plant biomass-degrading enzymes such as PoxCel7A-2, PoxCel5B, PoxBgl3A, PoxXyn11B, and PoxGA15A, as well as those involved in conidiation such as PoxBrlA. In vitro binding experiments further confirmed that PoxHmbB directly binds to the promoter regions of these major genes. These results further indicate the diversity of the biological functions of HMG-box proteins and provide a novel and promising engineering target for improving plant biomass-degrading enzyme production in filamentous fungi.

Deletion of TpKu70 facilitates gene targeting in Talaromyces pinophilus and identification of TpAmyR involvement in amylase production.

Talaromyces pinophilus is a promising filamentous fungus for industrial production of biomass-degrading enzymes used in biorefining, and its genome was recently sequenced and reported. However, functional analysis of genes in T. pinophilus is rather limited owing to lack of genetic tools. In this study, a putative TpKu70 encoding the Ku70 homolog involved in the classic non-homologous end-joining pathway was deleted in T. pinophilus 1-95. ΔTpKu70 displayed no apparent defect in vegetative growth and enzyme production, and presented similar sensitivity to benomyl, bleomycin, and UV, when compared with the wild-type T. pinophilus strain 1-95. Seven genes that encode putative transcription factors, including TpAmyR, were successfully knocked out in ΔTpKu70 at 61.5-100% of homologous recombination frequency, which is significantly higher than that noted in the wild-type. Interestingly, ΔTpAmyR produced approximately 20% of amylase secreted by the parent strain ΔTpKu70 in medium containing soluble starch from corn as the sole carbon source. Real-time quantitative reverse transcription PCR showed that TpAmyR positively regulated the expression of genes encoding α-amylase and glucoamylase. Thus, this study provides a useful tool for genetic analysis of T. pinophilus, and identification of a key role for the transcription factor TpAmyR in amylase production in T. pinophilus.

Exploring the potential causal relationship between gut microbiota and heart failure: A two-sample mendelian randomization study combined with the geo database.

OBJECTIVE: In recent years, researchers have observed a potential association between alterations in gut microbiota and the onset and progression of heart failure. Nevertheless, the causal relationship between gut microbiota and heart failure remains a topic of controversy. This study employed a two-sample Mendelian randomization approach to investigate the causal link between gut microbiota and heart failure. METHOD: We extracted single nucleotide polymorphism (SNPs) data for heart failure (ebi-a-gcst009541) and gut microbiota from the publicly available genome-wide association analysis (GWAS) summary database. The primary analytical method employed was inverse variance weighting (IVW), complemented by validation using MR-PRESSO, weighted median, and MR pleiotropic residual methods. Additionally, gene pleiotropy (MR-Egger), heterogeneity testing, and a "leave-one-out" analysis were conducted to assess the robustness of the findings. Utilizing the limma package, differentially expressed genes (DEGs) from the Gut Microbiota datasets (GSE3586, GSE5406) and Heart Failure datasets (GSE47908, GSE87466) sourced from the Gene Expression Omnibus (GEO) were curated. Subsequent enrichment analysis was conducted using the Cluster Profiler and GO plot packages to validate the MR analysis outcomes. RESULTS: The results of our analysis revealed seven distinct bacterial groups in the intestines that exhibited associations.with.the.risk.of.heart.failure. These.included.class.negativicutes (P = 0.02,OR:1.11,95%CI:1.02,1.21), gene.eubacterium.eligensgroup (P = 0.02,OR:1.10,95%CI:1.01,1.20),gene.eubacteriummoxidoreducensgroup (P = 0.01,OR:1.10,95%CI:1.02,1.19),Order.selenium (P = 0.02,OR:1.11,95%CI:1.02,1.21), gene.familyxiiiucg001 (P = 0.03,OR=1.09.95%CI:1.01,1.19), gene.familyxiiiad3011group (P = 0.03,OR:0.92,95%CI:0.86,0.99), and.gene.anaerostipes (P = 0.00,OR:0.87,95%CI:0.80,0.94). Nevertheless, upon conducting reverse causal MR analysis, no evidence of a causal relationship between heart failure and the aforementioned seven gut microbiota groups was found.Bioinformatics analysis reveals shared DEGs between gut microbiota and heart failure. CONCLUSION: This Mendelian randomization study represents the first endeavor to explore the causal relationship between specific gut microbiota and heart failure. The findings suggest a significant correlation between these seven specific gut microbiota groups and the risk of heart failure, potentially offering valuable insights for heart failure prevention and control efforts.

Corrigendum: Patchouli alcohol improved diarrhea-predominant irritable bowel syndrome by regulating excitatory neurotransmission in the myenteric plexus of rats.

[This corrects the article DOI: 10.3389/fphar.2022.943119.].

Moxibustion ameliorates visceral hypersensitivity by regulating hypothalamus-spinal cord-colon axis in rats with irritable bowel syndrome with diarrhea. / 基于下丘脑-脊髓-ç»“è‚ è½´æŽ¢è®¨è‰¾ç¸æ”¹å–„è ¹æ³»åž‹è‚ æ˜“æ¿€ç»¼åˆå¾å¤§é¼ å† è„é«˜æ•æ„Ÿçš„ä½œç”¨æœºåˆ¶.

OBJECTIVES: To observe the effect of moxibustion intervention on the hypothalamus-spinal cord-colon axis of rats with irritable bowel syndrome with diarrhea (IBS-D) and explore the mechanism of moxibustion in improving visceral hypersensitivity in rats with IBS-D. METHODS: A total of 36 SD rats were randomly divided into normal, model, and moxibustion groups, with 12 rats in each group. The IBS-D model was established by maternal separation + acetic acid stimulation + chronic restraint. Rats of the moxibustion group received bilateral moxibustion on "Tianshu" (ST25) and "Shangjuxu" (ST37) for 15 min, once a day for 7 consecutive days. The body weight, loose stool rate, and minimum threshold volume of abdominal withdrawal reflex (AWR) were measured before and after moxibustion intervention, respectively. The histopathological changes in the colon tissue were observed after HE staining. The number of colonic mucosal mast cells (MCs) was measured by toluidine blue staining. The activation of MCs was determined by tryptase positive expression level and examined by immunohistochemical staining. The content, protein and mRNA expression levels and positive expression levels of corticotropin releasing factor (CRF), substance P (SP), and calcitonin gene-related peptide (CGRP) in the hypothalamus, spinal cord and colon tissues were measured by ELISA, Western blot, real-time fluorescent quantitative PCR and immunofluorescence staining, respectively. RESULTS: Compared with the normal group, the loose stool rate was increased (P<0.01)；the body weight and minimum threshold volume of AWR were decreased (P<0.01)；the inflammatory infiltration of colon tissues was obvious；the number of MCs and positive expression level of tryptase in the colon tissue were increased (P<0.01)；the contents, positive expression le-vels, protein and mRNA expression levels of CRF, SP and CGRP in the hypothalamus, spinal cord and colon tissues were increased (P<0.01, P<0.05) in the model group. After the intervention, compared with the model group, all these indicators showed opposite trends (P<0.01, P<0.05) in the moxibustion group. CONCLUSIONS: Moxibustion can improve visceral hypersensitivity in rats with IBS-D, and its mechanism may be related to regulating the hypothalamic-spinal-colon axis to reduce the release of CRF, SP and CGRP, and thus to inhibite MC in colon tissue.

Electroacupuncture protects the intestinal mucosal barrier in diarrhea-predominant Irritable Bowel Syndrome rats by regulating the MCs/Tryptase/PAR-2/MLCK pathway.

OBJECTIVE: The pathogenesis of diarrhea-predominant irritable bowel syndrome (IBS-D) is related to damage to the intestinal mucosal barrier function. Based on the Mast cell (MC)/Tryptase/Protease-activated receptor-2 (PAR-2)/Myosin light chain kinase (MLCK) pathway, this study explored the effect of electroacupuncture (EA) on IBS-D rats and its possible mechanism of protecting the intestinal mucosal barrier. METHODS: The IBS-D rat model was established by mother-offspring separation, acetic acid enema, and chronic restraint stress. The efficacy of EA on IBS-D rats was evaluated by observing the rate of loose stool (LSP) and the minimum volume threshold of abdominal withdrawal reflex (AWR) in rats. Mast cells and the ultrastructure of intestinal mucosa were observed by H&E staining, toluidine blue staining, and transmission electron microscopy. The expression levels of Tryptase, PAR-2, MLCK, zonula occludens-1 (ZO-1), and Occludin in rats were detected by ELISA, qRT-PCR, and western blot. RESULTS: After 7 days of intervention, compared to the IBS-D group, the loose stool rates of rats in IBS-D + EA group and IBS-D + ketotifen group were decreased (P < 0.01), the minimum volume thresholds of AWR were improved (P < 0.01), the inflammation of colon tissue decreased, the number of MCs were decreased (P < 0.01), the expression of Tryptase, PAR-2, and MLCK were lowered (P < 0.01, P < 0.05), and the expression of ZO-1 and Occludin were enhanced (P < 0.01, P < 0.05). Compared to the EA group, there was no significant difference in each index between the ketotifen groups (P > 0.05). CONCLUSION: EA has a good therapeutic effect on IBS-D rats. Regulating the MCs/Tryptase/PAR-2/MLCK pathway may be a mechanism to protect the intestinal mucosal barrier.

Severe Organ Impairment Was Common in Elderly Individuals with Dengue in Guangdong, China.

Guangdong, China, has experienced several dengue epidemics involving thousands of confirmed cases in recent decades, and elderly individuals suffered severe dengue (SD) most seriously. However, the clinical characteristics and risk factors for SD among elderly patients in Guangdong have not been investigated. Patients older than 65 years were recruited and divided into a dengue fever (DF) group and an SD group according to the 2009 Dengue Guidelines of the WHO. We analyzed the clinical manifestations of the elderly patients with dengue and then assessed the risk factors for SD. Of a total of 1,027 patients, 868 patients were diagnosed as having DF and 159 as having SD. Of the 159 elderly patients with SD, 129 (81%) had comorbidities, with hypertension being the most common. Severe organ impairment (SOI) (115, 54%) was the most common presentation in SD patients, followed by severe plasma leakage (52, 24.4%) and severe hemorrhage (46, 21.6%). The most common symptom of SOI was kidney injury, followed by heart injury and central nervous system injury. Furthermore, multivariate regression revealed that the presence of chronic obstructive pulmonary disease (COPD), a lower red blood cell (RBC) count (≤3.5 × 1012/L; odds ratio [OR], 0.35; 95% CI, 0.17-0.55; P <0.001), lower serum albumin (ALB) (≤35 U/L; OR, 0.18; 95% CI, 0.09-0.32; P <0.001), and hyperpyrexia (body temperature ≥39°C; OR, 1.8; 95% CI, 1.2-2.6, P <0.001) were risk factors for SD. Severe organ impairment was the predominant manifestation in elderly individuals with SD characterized by kidney injury. The potential risk factors of SD such as presence of COPD and hyperpyrexia and lower RBC and ALB levels might help clinicians identify patients with SD early.

Rice Defense Responses Orchestrated by Oral Bacteria of the Rice Striped Stem Borer, Chilo suppressalis.

Plant defenses in response to chewing insects are generally regulated by jasmonic acid (JA) signaling pathway, whereas salicylic acid (SA) signaling is mainly involved in plant defense against biotrophic pathogens and piercing-sucking insects. Previous studies showed that both JA- and SA-related defenses in rice plants were triggered by the infestation of the rice striped stem borer (SSB, Chilo suppressalis), a destructive pest causing severe damage to rice production. Herbivore-associated microbes play an important role in modulating plant-insect interaction, and thus we speculate that the SSB symbiotic microbes acting as a hidden player may cause this anomalous result. The antibiotics (AB) treatment significantly depressed the performance of field-collected SSB larvae on rice plants, and reduced the quantities of bacteria around the wounds of rice stems compared to non-AB treatment. In response to mechanical wounding and oral secretions (OS) collected from non-AB treated larvae, rice plants exhibited lower levels of JA-regulated defenses, but higher levels of SA-regulated defenses compared to the treatment of OS from AB-treated larvae determined by using a combination of biochemical and molecular methods. Among seven culturable bacteria isolated from the OS of SSB larvae, Enterobacter and Acinetobacter contributed to the suppression of JA signaling-related defenses in rice plants, and axenic larvae reinoculated with these two strains displayed better performance on rice plants. Our findings demonstrate that SSB larvae exploit oral secreted bacteria to interfere with plant anti-herbivore defense and avoid fully activating the JA-regulated antiherbivore defenses of rice plants.