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In multicellular organisms, receptor tyrosine kinases (RTKs) control a variety of cellular processes, including cell proliferation, differentiation, migration, and survival. Sprouty (SPRY) proteins represent an important class of ligand‐inducible inhibitors of RTK‐dependent signaling pathways. Here, we investigated the role of SPRY1 in cells of the central nervous system (CNS). Expression of SPRY1 was substantially higher in neural stem cells than in cortical neurons and was increased during neuronal differentiation of cortical neurons. We found that SPRY1 was a direct target gene of the CNS‐specific microRNA, miR‐124 and miR‐132. In primary cultures of cortical neurons, the neurotrophic factors brain‐derived neurotrophic factor (BDNF) and Basic fibroblast growth factor (FGF2) downregulated SPRY1 expression to positively regulate their own functions. In immature cortical neurons and mouse N2A cells, we found that overexpression of SPRY1 inhibited neurite development, whereas knockdown of SPRY1 expression promoted neurite development. In mature neurons, overexpression of SPRY1 inhibited the prosurvival effects of both BDNF and FGF2 on glutamate‐mediated neuronal cell death. SPRY1 was also upregulated upon glutamate treatment in mature neurons and partially contributed to the cytotoxic effect of glutamate. Together, our results indicate that SPRY1 contributes to the regulation of CNS functions by influencing both neuronal differentiation under normal physiological processes and neuronal survival under pathological conditions. [ABSTRACT FROM AUTHOR]

A new combined difenoconazole and fluxapyroxad fungicide formulation, as an 11.7 % suspension concentrate (SC), has been introduced as part of a resistance management strategy. The dissipation of difenoconazole and fluxapyroxad applied to apples and the residues remaining in the apples were determined. The 11.7 % SC was sprayed onto apple trees and soil in Beijing, Shandong, and Anhui provinces, China, at an application rate of 118 g a.i. ha, then the dissipation of difenoconazole and fluxapyroxad was monitored. The residual difenoconazole and fluxapyroxad concentrations were determined by ultrahigh-performance liquid chromatography tandem mass spectrometry. The difenoconazole half-lives in apples and soil were 6.2-9.5 and 21.0-27.7 days, respectively. The fluxapyroxad half-lives in apples and soil were 9.4-12.6 and 10.3-36.5 days, respectively. Difenoconazole and fluxapyroxad residues in apples and soil after the 11.7 % SC had been sprayed twice and three times, with 10 days between applications, at 78 and 118 g a.i. ha were measured. Representative apple and soil samples were collected after the last treatment, at preharvest intervals of 14, 21, and 28 days. The difenoconazole residue concentrations in apples and soil were 0.002-0.052 and 0.002-0.298 mg kg, respectively. The fluxapyroxad residue concentrations in apples and soil were 0.002-0.093 and 0.008-1.219 mg kg, respectively. The difenoconazole and fluxapyroxad residue concentrations in apples were lower than the maximum residue limits (0.5 and 0.8 mg kg, respectively). An application rate of 78 g a.i. ha is therefore recommended to ensure that treated apples can be considered safe for humans to consume. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated an important role for miR-124, the most abundant and well-conserved brain-specific microRNA(miRNA), in promoting neurite outgrowth and elongation during neuronal differentiation. This miRNA's target genes and the mechanisms that execute this role remain unclear. In this study, we identified ROCK1, a small GTPase Rho kinase, as a direct target of miR-124 for regulating neurite elongation. miR-124 significantly inhibited ROCK1 expression in M17 cells. Inhibiting ROCK1 promoted neurite elongation, and the overexpression of ROCK1 strongly repressed the neurite elongation-enhancing effect of miR-124 in M17 cells. We determined that Akt functions as a novel ROCK1 downstream effector in regulating neurite outgrowth and elongation. [ABSTRACT FROM AUTHOR]

Hepatic stellate cells are of mesenchymal cell type located in the space of Disse. Upon liver injury, HSCs transactivate into myofibroblasts with increase in expression of fibrillar collagen, especially collagen I and III, leading to liver fibrosis. Previous studies have shown mTOR signaling is activated during liver fibrosis. However, there is no direct evidence in vivo. The aim of this study is to examine the effects of conditional deletion of TSC1 in mesenchymal on pathogenesis of liver fibrosis. Crossing mice bearing the floxed TSC1 gene with mice harboring Col1α2-Cre-ER(T) successfully generated progeny with a conditional knockout of TSC1 (TSC1 CKO) in collagen I expressing mesenchymal cells. TSC1 CKO and WT mice were subjected to CCl4, oil or CCl4+ rapamycin treatment for 8 weeks. TSC1 CKO mice developed pronounced liver fibrosis relative to WT mice, as examined by ALT, hydroxyproline, histopathology, and profibrogenic gene. Absence of TSC1 in mesenchymal cells induced proliferation and prevented apoptosis in activated HSCs. However, there were no significant differences in oil-treated TSC1 CKO and WT mice. Rapamycin, restored these phenotypic changes by preventing myofibroblasts proliferation and enhancing their apoptosis. These findings revealed mTOR overactivation in mesenchymal cells aggravates CCl4− induced liver fibrosis and the rapamycin prevent its occurance. [ABSTRACT FROM AUTHOR]

Background: The interplay between gut microbiome genera and inflammatory kidney-related diseases, such as nephrotic syndrome, glomerulonephritis, tubulo-interstitial nephritis, and chronic kidney disease, has been observed. However, the causal relationships between specific bacterial genera and these renal diseases have not been fully elucidated., Objective: To investigate the potential causal links between different genera of the gut microbiome and the susceptibility to various renal conditions utilizing two-sample Mendelian randomization (MR) analyses., Materials and Methods: Genome-wide association study (GWAS) summary statistics of gut microbiota and inflammatory kidney-related diseases were obtained from published GWASs. Two-sample MR analyses were conducted using methods including inverse-variance weighted (IVW), MR Egger, and others to identify potential causal links between gut microbial genera and renal conditions. Sensitivity analyses, including Cochran's Q test and the MR-PRESSO global test, were performed to validate the robustness of the results and detect horizontal pleiotropy. In addition, a reverse MR analysis was conducted to assess reverse causation possibilities., Results: By synthesizing insights from both primary and sensitivity analyses, this study unveiled critical associations of 12 bacterial genera with nephrotic syndrome, 7 bacterial genera with membranous nephropathy, 3 bacterial genera with glomerulonephritis, 4 bacterial genera with acute tubulo-interstitial nephritis, 6 bacterial genera with chronic tubulo-interstitial nephritis, and 7 bacterial genera with chronic kidney disease. Various genera were pinpointed as having either positive or negative causal relationships with these renal conditions, as evidenced by specific ranges of IVW-OR values (all P< 0.05). The congruence of the sensitivity analyses bolstered the primary findings, displaying no marked heterogeneity or horizontal pleiotropy. Notably, the reverse MR analysis with nephritis as the exposure did not reveal any causal relationships, thereby strengthening the resilience and validity of the primary associations., Conclusion: This study explored the causal associations between several gut microbial genera and the risk of several inflammatory kidney-related diseases, uncovering several associations between specific gut microbial genera and nephrotic syndrome, membranous nephropathy, glomerulonephritis, tubulo-interstitial nephritis, and chronic kidney disease. These findings enhance our understanding of the complex interplay between the gut microbiome and kidney diseases, and they will be beneficial for early diagnosis and subsequent treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Feng, Zhang, Lai, Jia, Wu and Chen.)

Objective: This study aimed to correlate the pulmonary surfactant B (SP-B) gene variation with bronchopulmonary dysplasia (BPD) in ethnic Han, Chinese, premature newborns., Method: 47 newborns with BPD and 55 controls without BPD were included. Genomic DNA was extracted from cord or artery blood. Genotyping for the SP-B gene was performed by polymerase chain reaction or gene sequencing, and the clinical characteristics were also analyzed., Results: Two types of SP-B gene variations in Exon 2 or Exon 5 were discovered, including V1 (Exon 2: c.[5A > C] + [5A > C] or c.[5A > C] + [=]) and V2 (Exon 5: c.[428C > T] + [428C > T] or c.[428C > T] + [=]). In the BPD group, there were 33 newborns with gene variations, of which type V1 and V2 accounted for 18 and 15 respectively. In the control group, there were 19 newborns with gene variations, of which type V1 and V2 accounted for 7 and 12 respectively. There was a significant difference between the two groups in type V1 variation (X 2 =8.956, P < 0.05), and V1 variation was more likely associated with BPD occurrence. Logistic regression analysis showed that gene variation, premature rupture of membranes, birth weight, and the duration of mechanical ventilation were associated with BPD development. Among them, gene variation and premature rupture of the membranes were risk factors for BPD development., Conclusions: The exon 2 or 5 of SP-B gene variations were associated with the BPD in Chinese premature newborns, and the type V1: Exon 2: c.[5A > C] + [5A > C] or c.[5A > C] + [=] was a risk factor for the development of BPD., Competing Interests: None., (IJCEP Copyright © 2018.)

The class IIa histone deacetylases (HDACs) play important roles in the central nervous system during diverse biological processes such as synaptic plasticity, axon regeneration, cell apoptosis, and neural differentiation. Although it is known that HDAC5 regulates neuronal differentiation, neither the physiological function nor the regulation of HDAC5 in neuronal differentiation is clear. Here, we identify HDAC5 as an inhibitor of neurite elongation and show that HDAC5 is regulated by the brain enriched microRNA miR-124 and miR-9. We discover that HDAC5 inhibits neurite extension both in differentiated P19 cells and primary neurons. We also show that the neuronal membrane glycoprotein GPM6A (M6a) is a direct target gene of HDAC5 regulated transcriptional factor MEF2C. HDAC5 inhibits neurite elongation, acting at least partially via a MEF2C/M6a signaling pathway. We also confirmed the miR-124/miR-9 regulated HDAC5-MEF2C-M6a pathway regulates neurite development in primary neurons. Thus, HDAC5 emerges as a cellular conductor of MEF2C and M6a activity and is regulated by miR-124 and miR-9 to control neurite development., (© 2017 Wiley Periodicals, Inc.)

Hepatic stellate cells are of mesenchymal cell type located in the space of Disse. Upon liver injury, HSCs transactivate into myofibroblasts with increase in expression of fibrillar collagen, especially collagen I and III, leading to liver fibrosis. Previous studies have shown mTOR signaling is activated during liver fibrosis. However, there is no direct evidence in vivo. The aim of this study is to examine the effects of conditional deletion of TSC1 in mesenchymal on pathogenesis of liver fibrosis. Crossing mice bearing the floxed TSC1 gene with mice harboring Col1α2-Cre-ER(T) successfully generated progeny with a conditional knockout of TSC1 (TSC1 CKO) in collagen I expressing mesenchymal cells. TSC1 CKO and WT mice were subjected to CCl 4 , oil or CCl 4 + rapamycin treatment for 8 weeks. TSC1 CKO mice developed pronounced liver fibrosis relative to WT mice, as examined by ALT, hydroxyproline, histopathology, and profibrogenic gene. Absence of TSC1 in mesenchymal cells induced proliferation and prevented apoptosis in activated HSCs. However, there were no significant differences in oil-treated TSC1 CKO and WT mice. Rapamycin, restored these phenotypic changes by preventing myofibroblasts proliferation and enhancing their apoptosis. These findings revealed mTOR overactivation in mesenchymal cells aggravates CCl 4 - induced liver fibrosis and the rapamycin prevent its occurance.

Previous studies have reported that mTORC2 promotes cell survival through phosphorylating AKT and enhancing its activity. We reveal another mechanism by which mTORC2 controls apoptosis. Inactivation of mTORC2 promotes binding of CIP2A to PP2A, leading to reduced PP2A activity toward c-Myc serine 62 and, consequently, enhancement of c-Myc phosphorylation and expression. Increased c-Myc activity induces transcription of pri-miR-9-2/miR-9-3p, in turn inhibiting expression of E2F1, a transcriptional factor critical for cancer cell survival and tumor progression, resulting in enhanced apoptosis. In vivo experiments using B cell-specific mTORC2 (rapamycin-insensitive companion of mTOR) deletion mice and a xenograft tumor model confirmed that inactivation of mTORC2 causes up-regulation of c-Myc and miR-9-3p, down-regulation of E2F1, and consequent reduction in cell survival. Conversely, Antagomir-9-3p reversed mTORC1/2 inhibitor-potentiated E2F1 suppression and resultant apoptosis in xenograft tumors. Our in vitro and in vivo findings collectively demonstrate that mTORC2 promotes cell survival by stimulating E2F1 expression through a c-Myc- and miR-9-3p-dependent mechanism., (© 2015 Zou et al.)

A gas chromatography-mass spectrometry (GC-MS) method for the determination of hexachlorocyclohexane (BHC) and dichlorodiphenyltrichloroethane (DDT) residues in honey was developed using dispersive liquid-liquid microextraction (DLLME) as sample preparation method. The samples were extracted with chloroform, and concentrated into chloroform by vortex and centrifuging. The analytes were analyzed by GC-MS. The factors affecting the extraction efficiency were investigated, such as the type and volume of extraction and dispersive solvent, extraction time, etc. The matrix effects and method performance were evaluated at the same time. The results indicated that all the eight BHC and DDT pesticides displayed the enhancement of signals due to the matrix effects. The calibration curves were linear in the range of 2-500 microg/L and the correlation coefficients were 0.991-0.998 for the eight BHC and DDT pesticides. The enrichment factors (EF) were 74-96 for the eight pesticides. The recoveries of the eight BHC and DDT pesticides at three spiked levels of 20, 50 and 100 microg/kg were 61.0%-100.1%, while the RSDs were 2.2%-19.5%. The limits of quantification for the eight pesticides were 20 microg/kg, and the limits of detection were 1.0 ng. The developed method is easy, quick and with high performance. It is applicable for the determination of BHC and DDT residues in honey.