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Journal of Molecular Neuroscience : MN Jun 2024Binge drinking causes a range of problems especially damage to the nervous system, and the specific neural mechanism of brain loss and behavioral abnormalities caused by...
Binge drinking causes a range of problems especially damage to the nervous system, and the specific neural mechanism of brain loss and behavioral abnormalities caused by which is still unclear. Extracellular regulated protein kinases (ERK) maintain neuronal survival, growth, and regulation of synaptic plasticity by phosphorylating specific transcription factors to regulate expression of brain-derived neurotrophic factor (BDNF). Dual-specific phosphatase 1 (DUSP1) and DUSP6 dephosphorylate tyrosine and serine/threonine residues in ERK1/2 to inactivate them. To investigate the molecular mechanism by which alcohol affects memory and emotion, a chronic intermittent alcohol exposure (CIAE) model was established. The results demonstrated that mice in the CIAE group developed short-term recognition memory impairment and anxiety-like behavior; meanwhile, the expression of DUSP1 and DUSP66 in the mPFC was increased, while the levels of p-ERK and BDNF were decreased. Micro-injection of DUSP1/6 inhibitor BCI into the medial prefrontal cortex (mPFC) restored the dendritic morphology by reversing the activity of ERK-BDNF and ultimately improved cognitive and emotional impairment caused by CIAE. These findings indicate that CIAE inhibits ERK-BDNF by increasing DUSP1/6 in the mPFC that may be associated with cognitive and emotional deficits. Consequently, DUSP1 and DUSP6 appear to be potential targets for the treatment of alcoholic brain disorders.
Topics: Animals; Brain-Derived Neurotrophic Factor; Mice; Male; Mice, Inbred C57BL; Dual Specificity Phosphatase 1; Prefrontal Cortex; Ethanol; Dual Specificity Phosphatase 6; Aminoacetonitrile; Anxiety; MAP Kinase Signaling System
PubMed: 38890235
DOI: 10.1007/s12031-024-02237-z -
Biochemistry. Biokhimiia May 2024Lymphocyte phosphatase-associated phosphoprotein (LPAP) is a binding partner of the phosphatase CD45, but its function remains poorly understood. Its close interaction...
Lymphocyte phosphatase-associated phosphoprotein (LPAP) is a binding partner of the phosphatase CD45, but its function remains poorly understood. Its close interaction with CD45 suggests that LPAP may potentially regulate CD45, but direct biochemical evidence for this has not yet been obtained. We found that in the Jurkat lymphoid cells the levels of LPAP and CD45 proteins are interrelated and well correlated with each other. Knockout of LPAP leads to the decrease in the surface expression of CD45, while its overexpression, on the contrary, caused its increase. No such correlation was found in the non-lymphoid K562 cells. We hypothesize that LPAP regulates expression level of CD45 and thus can affect lymphocyte activation.
Topics: Humans; Leukocyte Common Antigens; Jurkat Cells; K562 Cells; Protein Stability; Phosphoproteins
PubMed: 38880651
DOI: 10.1134/S0006297924050110 -
Journal of Pharmacological Sciences Aug 2024Previously, we have shown that pyrogallol alleviated nasal symptoms and suppressed IL-9 gene up-regulation in allergy model rats by inhibiting calcineurin/NFAT...
Previously, we have shown that pyrogallol alleviated nasal symptoms and suppressed IL-9 gene up-regulation in allergy model rats by inhibiting calcineurin/NFAT signaling. As pyrogallol has antioxidative activity, it may be responsible for inhibiting calcineurin/NFAT signaling-mediated IL-9 gene expression. However, the relationship between antioxidative activity and suppression of IL-9 gene expression has not been elucidated yet. Here, we conducted the structure-activity relationship studies of pyrogallol and its structurally related compounds to understand the mechanism of IL-9 gene suppression by pyrogallol. 2, 2-Diphenyl-1-picrylhydrazyl radical scavenging assay showed that the antioxidative activity of catechol, resorcinol, phloroglucinol, and gallic acid is 60.1%, 10.4%, 18.8%, and 113.5% of pyrogallol, respectively. Catechol, resorcinol, and phloroglucinol did not suppress NFAT dephosphorylation. Gallic acid suppressed dephosphorylation of NFAT. Gallic acid also suppressed ionomycin-induced up-regulation of IL-9 gene expression with the IC value of 82.6 μM. However, catechol, resorcinol and phloroglucinol showed no suppressive activity. In addition, using gallic acid-immobilized beads, we isolated and identified Poly(U)-binding-splicing factor 60 (PUF60) as a pyrogallol binding protein. These results suggest that the antioxidative activity of pyrogallol is not likely to be the mechanism of IL-9 gene suppression. Data also suggest that PUF60 is one of its target molecules responsible for the suppression of calcineurin/NFAT signaling by pyrogallol.
Topics: Pyrogallol; Calcineurin; Signal Transduction; NFATC Transcription Factors; Structure-Activity Relationship; Antioxidants; Humans; Gallic Acid; Gene Expression; Animals; Phosphorylation; Up-Regulation; Rats
PubMed: 38880548
DOI: 10.1016/j.jphs.2024.06.002 -
Molecular Medicine (Cambridge, Mass.) Jun 2024Myocardial infarction (MI) leads to enhanced activity of cardiac fibroblasts (CFs) and abnormal deposition of extracellular matrix proteins, resulting in cardiac...
BACKGROUND
Myocardial infarction (MI) leads to enhanced activity of cardiac fibroblasts (CFs) and abnormal deposition of extracellular matrix proteins, resulting in cardiac fibrosis. Tartrate-resistant acid phosphatase 5 (ACP5) has been shown to promote cell proliferation and phenotypic transition. However, it remains unclear whether ACP5 is involved in the development of cardiac fibrosis after MI. The present study aimed to investigate the role of ACP5 in post-MI fibrosis and its potential underlying mechanisms.
METHODS
Clinical blood samples were collected to detect ACP5 concentration. Myocardial fibrosis was induced by ligation of the left anterior descending coronary artery. The ACP5 inhibitor, AubipyOMe, was administered by intraperitoneal injection. Cardiac function and morphological changes were observed on Day 28 after injury. Cardiac CFs from neonatal mice were extracted to elucidate the underlying mechanism in vitro. The expression of ACP5 was silenced by small interfering RNA (siRNA) and overexpressed by adeno-associated viruses to evaluate its effect on CF activation.
RESULTS
The expression of ACP5 was increased in patients with MI, mice with MI, and mice with Ang II-induced fibrosis in vitro. AubipyOMe inhibited cardiac fibrosis and improved cardiac function in mice after MI. ACP5 inhibition reduced cell proliferation, migration, and phenotypic changes in CFs in vitro, while adenovirus-mediated ACP5 overexpression had the opposite effect. Mechanistically, the classical profibrotic pathway of glycogen synthase kinase-3β (GSK3β)/β-catenin was changed with ACP5 modulation, which indicated that ACP5 had a positive regulatory effect. Furthermore, the inhibitory effect of ACP5 deficiency on the GSK3β/β-catenin pathway was counteracted by an ERK activator, which indicated that ACP5 regulated GSK3β activity through ERK-mediated phosphorylation, thereby affecting β-catenin degradation.
CONCLUSION
ACP5 may influence the proliferation, migration, and phenotypic transition of CFs, leading to the development of myocardial fibrosis after MI through modulating the ERK/GSK3β/β-catenin signaling pathway.
Topics: Animals; Fibrosis; Myocardial Infarction; Mice; Humans; Tartrate-Resistant Acid Phosphatase; Male; Cell Proliferation; Disease Models, Animal; Fibroblasts; Myocardium; Glycogen Synthase Kinase 3 beta; Mice, Inbred C57BL; Signal Transduction; Cell Movement
PubMed: 38879488
DOI: 10.1186/s10020-024-00856-1 -
Nature Communications Jun 2024Phosphorylation of cardiac myosin binding protein-C (cMyBP-C) is a determinant of cardiac myofilament function. Although cMyBP-C phosphorylation by various protein...
Phosphorylation of cardiac myosin binding protein-C (cMyBP-C) is a determinant of cardiac myofilament function. Although cMyBP-C phosphorylation by various protein kinases has been extensively studied, the influence of protein phosphatases on cMyBP-C's multiple phosphorylation sites has remained largely obscure. Here we provide a detailed biochemical characterization of cMyBP-C dephosphorylation by protein phosphatases 1 and 2 A (PP1 and PP2A), and develop an integrated kinetic model for cMyBP-C phosphorylation using data for both PP1, PP2A and various protein kinases known to phosphorylate cMyBP-C. We find strong site-specificity and a hierarchical mechanism for both phosphatases, proceeding in the opposite direction of sequential phosphorylation by potein kinase A. The model is consistent with published data from human patients and predicts complex non-linear cMyBP-C phosphorylation patterns that are validated experimentally. Our results suggest non-redundant roles for PP1 and PP2A under both physiological and heart failure conditions, and emphasize the importance of phosphatases for cMyBP-C regulation.
Topics: Phosphorylation; Humans; Protein Phosphatase 1; Carrier Proteins; Animals; Protein Phosphatase 2; Myocardium; Protein Kinases; Kinetics
PubMed: 38877002
DOI: 10.1038/s41467-024-49408-5 -
Life Sciences Aug 2024Exosomes play a crucial role in promoting tumor progression, dissemination, and resistance to treatment. These extracellular vesicles hold promise as valuable indicators...
BACKGROUND
Exosomes play a crucial role in promoting tumor progression, dissemination, and resistance to treatment. These extracellular vesicles hold promise as valuable indicators for cancer detection. Our investigation focuses on exploring the significance and clinical relevance of exosomal miRNAs in small cell lung cancer (SCLC).
METHODS
Serum exosomes were isolated from both SCLC patients and healthy controls, and subjected to exosomal miRNA sequencing analysis. Mimics and inhibitors were employed to investigate the function of exosomal miR-1128-5p in cell migration and proliferation, both in vitro and in vivo. Western blot and luciferase assay were utilized to identify the interaction between miR-1228-5p and dual specificity phosphatase 22 (DUSP22).
RESULTS
Exosomal miRNA sequencing analysis revealed enrichment of specific miRNAs in SCLC compared to healthy controls. Circulating miR-1228-5p was upregulated in SCLC patients, associated with advanced stages, suggesting its potential oncogenic role. In vitro, miR-1228-5p expression was significantly higher in SCLC cells than in normal cells. SCLC cell-derived exosomes contained elevated levels of miR-1228-5p, facilitating its entry into co-cultured cells. Notably, migration and proliferation induced by SCLC exosomes were mainly mediated by miR-1228-5p. In vivo experiments confirmed these findings. Western blot analysis demonstrated miR-1228-5p's regulation of DUSP22 expression, and luciferase reporter assay validated DUSP22 as a direct target gene. Overexpressing DUSP22 counteracted miR-1228-5p's promotion of SCLC cell proliferation and migration.
CONCLUSIONS
Collectively, our results suggest that exosomes play a role in facilitating cancer growth and metastasis by delivering miR-1228-5p. Moreover, circulating exosomal miR-1228-5p may serve as a potential marker for SCLC diagnosis and prognosis.
Topics: Humans; MicroRNAs; Exosomes; Cell Proliferation; Cell Movement; Lung Neoplasms; Small Cell Lung Carcinoma; Male; Female; Dual-Specificity Phosphatases; Animals; Mice; Mitogen-Activated Protein Kinase Phosphatases; Middle Aged; Down-Regulation; Gene Expression Regulation, Neoplastic; Cell Line, Tumor; Mice, Nude; Mice, Inbred BALB C; Aged
PubMed: 38851418
DOI: 10.1016/j.lfs.2024.122787 -
Molecular Cell Jun 2024The interconnections between co-transcriptional regulation, chromatin environment, and transcriptional output remain poorly understood. Here, we investigate the...
The interconnections between co-transcriptional regulation, chromatin environment, and transcriptional output remain poorly understood. Here, we investigate the mechanism underlying RNA 3' processing-mediated Polycomb silencing of Arabidopsis FLOWERING LOCUS C (FLC). We show a requirement for ANTHESIS PROMOTING FACTOR 1 (APRF1), a homolog of yeast Swd2 and human WDR82, known to regulate RNA polymerase II (RNA Pol II) during transcription termination. APRF1 interacts with TYPE ONE SERINE/THREONINE PROTEIN PHOSPHATASE 4 (TOPP4) (yeast Glc7/human PP1) and LUMINIDEPENDENS (LD), the latter showing structural features found in Ref2/PNUTS, all components of the yeast and human phosphatase module of the CPF 3' end-processing machinery. LD has been shown to co-associate in vivo with the histone H3 K4 demethylase FLOWERING LOCUS D (FLD). This work shows how the APRF1/LD-mediated polyadenylation/termination process influences subsequent rounds of transcription by changing the local chromatin environment at FLC.
Topics: Arabidopsis Proteins; Arabidopsis; Chromatin; Gene Expression Regulation, Plant; MADS Domain Proteins; Transcription Termination, Genetic; RNA Polymerase II; Gene Silencing; Phosphoprotein Phosphatases; mRNA Cleavage and Polyadenylation Factors; Histones; Histone Deacetylases
PubMed: 38851185
DOI: 10.1016/j.molcel.2024.05.016 -
Plant Physiology and Biochemistry : PPB Jul 2024Drought is a major environmental stress that limits plant growth, so it's important to identify drought-responsive genes to understand the mechanism of drought response...
Drought is a major environmental stress that limits plant growth, so it's important to identify drought-responsive genes to understand the mechanism of drought response and breed drought-tolerant roses. Protein phosphatase 2C (PP2C) plays a crucial role in plant abiotic stress response. In this study, we identified 412 putative PP2Cs from six Rosaceae species. These genes were divided into twelve clades, with clade A containing the largest number of PP2Cs (14.1%). Clade A PP2Cs are known for their important role in ABA-mediated drought stress response; therefore, the analysis focused on these specific genes. Conserved motif analysis revealed that clade A PP2Cs in these six Rosaceae species shared conserved C-terminal catalytic domains. Collinearity analysis indicated that segmental duplication events played a significant role in the evolution of clade A PP2Cs in Rosaceae. Analysis of the expression of 11 clade A RcPP2Cs showed that approximately 60% of these genes responded to drought, high temperature, and salt stress. Among them, RcPP2C24 exhibited the highest responsiveness to both drought and ABA. Furthermore, overexpression of RcPP2C24 significantly reduced drought tolerance in transgenic tobacco by increasing stomatal aperture after exposure to drought stress. The transient overexpression of RcPP2C24 weakened the dehydration tolerance of rose petal discs, while its silencing increased their dehydration tolerance. In summary, our study identified PP2Cs in six Rosaceae species and highlighted the negative role of RcPP2C24 on rose's drought tolerance by inhibiting stomatal closure. Our findings provide valuable insights into understanding the mechanism behind rose's response to drought.
Topics: Plant Proteins; Protein Phosphatase 2C; Gene Expression Regulation, Plant; Droughts; Rosa; Plants, Genetically Modified; Rosaceae; Nicotiana; Phylogeny; Abscisic Acid; Stress, Physiological; Dehydration; Drought Resistance
PubMed: 38850728
DOI: 10.1016/j.plaphy.2024.108782 -
The Journal of Clinical Investigation Jun 2024Aberrant activation of RAS-MAPK signaling is common in cancer, and efforts to inhibit pathway components have yielded drugs with promising clinical activities....
Aberrant activation of RAS-MAPK signaling is common in cancer, and efforts to inhibit pathway components have yielded drugs with promising clinical activities. Unfortunately, treatment-provoked adaptive resistance mechanisms inevitably develop, limiting their therapeutic potential. As a central node essential for receptor tyrosine kinase mediated RAS activation, SHP2 has emerged as an attractive cancer target. Consequently, many SHP2 allosteric inhibitors are now in clinical testing. Here we discovered a previously unrecognized off-target effect associated with SHP2 allosteric inhibitors. We found that these inhibitors accumulate in the lysosome and block autophagic flux in a SHP2-independent manner. We showed that off-target autophagy inhibition by SHP2 allosteric inhibitors contributes to their anti-tumor activity. We also demonstrated that SHP2 allosteric inhibitors harboring this off-target activity not only suppress oncogenic RAS signaling but also overcome drug resistance such as MAPK rebound and protective autophagy in response to RAS-MAPK pathway blockage. Finally, we exemplified a therapeutic framework that harnesses both the on- and off-target activities of SHP2 allosteric inhibitors for improved treatment of mutant RAS driven and drug resistant malignancies such as pancreatic and colorectal cancers. Brief Summary: SHP2 allosteric inhibitors elicit off-target autophagy blockade that can be exploited for improved treatment of RAS-driven and drug-resistant cancers.
PubMed: 38842946
DOI: 10.1172/JCI177142 -
European Journal of Pharmacology Aug 2024Histone deacetylase (HDAC) inhibitors are potential candidates for treating pulmonary fibrosis. MPT0E028, a novel pan-HDAC inhibitor, has been reported to exhibit...
MPT0E028, a novel pan-HDAC inhibitor, prevents pulmonary fibrosis through inhibition of TGF-β-induced CTGF expression in human lung fibroblasts: Involvement of MKP-1 activation.
Histone deacetylase (HDAC) inhibitors are potential candidates for treating pulmonary fibrosis. MPT0E028, a novel pan-HDAC inhibitor, has been reported to exhibit antitumor activity in several cancer cell lines. In this study, we investigated the mechanism underlying the inhibitory effects of MPT0E028 on the expression of fibrogenic proteins in human lung fibroblasts (WI-38). Our results revealed that MPT0E028 inhibited transforming growth factor-β (TGF-β)-, thrombin-, and endothelin 1-induced connective tissue growth factor (CTGF) expression in a concentration-dependent manner. In addition, MPT0E028 suppressed TGF-β-stimulated expression of fibronectin, collagen I, and α-smooth muscle actin (α-SMA). Furthermore, MPT0E028 inhibited the TGF-β-induced phosphorylation of c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase (ERK). MPT0E028 reduced the increase in SMAD3 and c-Jun phosphorylation, and SMAD3-and activator protein-1 (AP-1)-luciferase activities under TGF-β stimulation. Transfection with mitogen-activated protein kinase phosphatase-1 (MKP-1) siRNA reversed the suppressive effects of MPT0E028 on TGF-β-induced increases in CTGF expression; JNK, p38, and ERK phosphorylation; and SMAD3 and AP-1 activation. Moreover, MPT0E028 increased MKP-1 acetylation and activity in WI-38 cells. Pretreatment with MPT0E028 reduced the fibrosis score and fibronectin, collagen, and α-SMA expression in bleomycin-induced pulmonary fibrosis mice. In conclusion, MPT0E028 induced MKP-1 acetylation and activation, which in turn inhibited TGF-β-stimulated JNK, p38, and ERK phosphorylation; SMAD3 and AP-1 activation; and subsequent CTGF expression in human lung fibroblasts. Thus, MPT0E028 may be a potential drug for treating pulmonary fibrosis.
Topics: Connective Tissue Growth Factor; Humans; Fibroblasts; Pulmonary Fibrosis; Animals; Histone Deacetylase Inhibitors; Mice; Lung; Transforming Growth Factor beta; Dual Specificity Phosphatase 1; Cell Line; Smad3 Protein; Phosphorylation; Male; Enzyme Activation; Mice, Inbred C57BL
PubMed: 38839029
DOI: 10.1016/j.ejphar.2024.176711