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Frontiers in Bioscience (Landmark... Jun 2024Persistent hyperuricemia can lead to the generation and deposition of monosodium urate (MSU) crystals. This can trigger gouty arthritis (GA), which in turn induces...
BACKGROUND
Persistent hyperuricemia can lead to the generation and deposition of monosodium urate (MSU) crystals. This can trigger gouty arthritis (GA), which in turn induces inflammation. Activation of the Nod-like receptor pyrin domain containing 3 (NLRP3) inflammasome plays a critical role in the onset and progression of GA. Autophagy may have a dual effect on GA with regard to the NLRP3 inflammasome. Therefore, the present study aimed to gain a deeper comprehension of the interaction between autophagy and NLRP3 inflammasome activation is imperative for developing more efficacious treatments for GA.
METHODS
Peripheral blood monocytes (PBMCs) were first isolated from GA patients and healthy controls and underwent bulk RNA sequencing analysis. Overexpression and knockdown of dual specificity phosphatase 1 (DUSP1) was performed in THP-1 monocytes to investigate its role in the immune response and mitochondrial damage. The luciferase assay and Western blot analysis were used to study the interaction between autophagy and NLRP3 inflammasome activation.
RESULTS
Bulk RNA sequencing analysis showed significant upregulation of DUSP1 expression in PBMCs from GA patients compared to healthy controls. This result was subsequently verified by reverse transcription quantitative polymerase chain reaction (RT-qPCR). DUSP1 expression in human THP-1 monocytes was also shown to increase after MSU treatment. Downregulation of DUSP1 expression increased the secretion of inflammatory cytokines after MSU treatment, whereas the overexpression of DUSP1 decreased the secretion levels. Lipopolysaccharides (LPS) combined with adenosine-triphosphate (ATP) led to mitochondrial damage, which was rescued by overexpressing DUSP1. DUSP1 overexpression further increased the level of autophagy following MSU treatment, whereas downregulation of DUSP1 decreased autophagy. Treatment with the autophagy inhibitor 3-Methyladenine (3-MA) restored inflammatory cytokine secretion levels in the DUSP1 overexpression group. MSU caused pronounced pathological ankle swelling . However, DUSP1 overexpression significantly mitigated this phenotype, accompanied by significant downregulation of inflammatory cytokine secretion levels in the joint tissues.
CONCLUSIONS
This study revealed a novel function and mechanism for DUSP1 in promoting autophagy to mitigate the MSU-induced immune response in GA. This finding suggests potential diagnostic biomarkers and anti-inflammatory targets for more effective GA therapy.
Topics: Humans; Autophagy; Dual Specificity Phosphatase 1; Arthritis, Gouty; Uric Acid; NLR Family, Pyrin Domain-Containing 3 Protein; Inflammasomes; THP-1 Cells; Male; Monocytes; Case-Control Studies; Female; Leukocytes, Mononuclear; Middle Aged
PubMed: 38940057
DOI: 10.31083/j.fbl2906222 -
Frontiers in Bioscience (Landmark... Jun 2024This study investigated the impact of salvianolic acids, derived from Danshen, on melanoma cell growth. Specifically, we assessed the ability of salvianolic acid A (Sal...
BACKGROUND
This study investigated the impact of salvianolic acids, derived from Danshen, on melanoma cell growth. Specifically, we assessed the ability of salvianolic acid A (Sal A) to modulate melanoma cell proliferation.
METHODS
We used human melanoma A2058 and A375 cell lines to investigate the effects of Sal A on cell proliferation and death by measuring bromodeoxyuridine incorporation and lactate dehydrogenase release. We assessed cell viability and cycle progression using water soluble tetrazolium salt-1 (WST-1) mitochondrial staining and propidium iodide. Additionally, we used a phospho-kinase array to investigate intracellular kinase phosphorylation, specifically measuring the influence of Sal A on checkpoint kinase-2 (Chk-2) via western blot analysis.
RESULTS
Sal A inhibited the growth of A2058 and A375 cells dose-responsively and induced cell cycle arrest at the G2/M phase. Notably, Sal A selectively induces Chk-2 phosphorylation without affecting Chk-1, thereby degrading Chk-2-regulated genes and . However, Sal A does not affect the Chk1-Cdc25C pathway.
CONCLUSIONS
Salvianolic acids, especially Sal A, effectively hinder melanoma cell growth by inducing Chk-2 phosphorylation and disrupting G2/M checkpoint regulation.
Topics: Humans; Checkpoint Kinase 2; cdc25 Phosphatases; Melanoma; Cell Line, Tumor; Cell Proliferation; Lactates; Caffeic Acids; Signal Transduction; Phosphorylation; Cell Survival
PubMed: 38940031
DOI: 10.31083/j.fbl2906213 -
Hepatology Communications Jul 2024The incidence of gallbladder diseases is as high as 20%, but whether gallbladder diseases contribute to hepatic disorders remains unknown.
BACKGROUND
The incidence of gallbladder diseases is as high as 20%, but whether gallbladder diseases contribute to hepatic disorders remains unknown.
METHODS
Here, we established an animal model of gallbladder dysfunction and assessed the role of a diseased gallbladder in cholestasis-induced hepatic fibrosis (CIHF).
RESULTS
Mice with smooth muscle-specific deletion of Mypt1, the gene encoding the main regulatory subunit of myosin light chain phosphatase (myosin phosphatase target subunit 1 [MYPT1]), had apparent dysfunction of gallbladder motility. This dysfunction was evidenced by abnormal contractile responses, namely, inhibited cholecystokinin 8-mediated contraction and nitric oxide-resistant relaxation. As a consequence, the gallbladder displayed impaired bile filling and biliary tract dilation comparable to the alterations in CIHF. Interestingly, the mutant animals also displayed CIHF features, including necrotic loci by the age of 1 month and subsequently exhibited progressive fibrosis and hyperplastic/dilated bile ducts. This pathological progression was similar to the phenotypes of the animal model with bile duct ligation and patients with CIHF. The characteristic biomarker of CIHF, serum alkaline phosphatase activity, was also elevated in the mice. Moreover, we observed that the myosin phosphatase target subunit 1 protein level was able to be regulated by several reagents, including lipopolysaccharide, exemplifying the risk factors for gallbladder dysfunction and hence CIHF.
CONCLUSIONS
We propose that gallbladder dysfunction caused by myosin phosphatase target subunit 1 ablation is sufficient to induce CIHF in mice, resulting in impairment of the bile transport system.
Topics: Animals; Myosin-Light-Chain Phosphatase; Mice; Disease Models, Animal; Liver Cirrhosis; Cholestasis; Gallbladder Diseases; Gallbladder; Male; Mice, Knockout
PubMed: 38934703
DOI: 10.1097/HC9.0000000000000473 -
International Journal of Molecular... Jun 2024Valosin-containing protein (VCP), an ATPase-associated protein, is emerging as a crucial regulator in cardiac pathologies. However, the pivotal role of VCP in the heart...
Cardiac-Specific Suppression of Valosin-Containing Protein Induces Progressive Heart Failure and Premature Mortality Correlating with Temporal Dysregulations in mTOR Complex 2 and Protein Phosphatase 1.
Valosin-containing protein (VCP), an ATPase-associated protein, is emerging as a crucial regulator in cardiac pathologies. However, the pivotal role of VCP in the heart under physiological conditions remains undetermined. In this study, we tested a hypothesis that sufficient VCP expression is required for cardiac development and physiological cardiac function. Thus, we generated a cardiac-specific VCP knockout (KO) mouse model and assessed the consequences of VCP suppression on the heart through physiological and molecular studies at baseline. Our results reveal that homozygous KO mice are embryonically lethal, whereas heterozygous KO mice with a reduction in VCP by ~40% in the heart are viable at birth but progressively develop heart failure and succumb to mortality at the age of 10 to 12 months. The suppression of VCP induced a selective activation of the mammalian target of rapamycin complex 1 (mTORC1) but not mTORC2 at the early age of 12 weeks. The prolonged suppression of VCP increased the expression (by ~2 folds) and nuclear translocation (by >4 folds) of protein phosphatase 1 (PP1), a key mediator of protein dephosphorylation, accompanied by a remarked reduction (~80%) in AKTSer473 phosphorylation in VCP KO mouse hearts at a later age but not the early stage. These temporal molecular alterations were highly associated with the progressive decline in cardiac function. Overall, our findings shed light on the essential role of VCP in the heart under physiological conditions, providing new insights into molecular mechanisms in the development of heart failure.
Topics: Animals; Heart Failure; Valosin Containing Protein; Mice; Mice, Knockout; Protein Phosphatase 1; Mechanistic Target of Rapamycin Complex 2; Myocardium; Male; Disease Models, Animal
PubMed: 38928151
DOI: 10.3390/ijms25126445 -
Scientific Reports Jun 2024Excess amounts of histones in the cell induce mitotic chromosome loss and genomic instability, and are therefore detrimental to cell survival. In yeast, excess histones...
Excess amounts of histones in the cell induce mitotic chromosome loss and genomic instability, and are therefore detrimental to cell survival. In yeast, excess histones are degraded by the proteasome mediated via the DNA damage response factor Rad53. Histone expression, therefore, is tightly regulated at the protein level. Our understanding of the transcriptional regulation of histone genes is far from complete. In this study, we found that calcineurin inhibitor treatment increased histone protein levels, and that the transcription factor NFATc1 (nuclear factor of activated T cells 1) repressed histone transcription and acts downstream of the calcineurin. We further revealed that NFATc1 binds to the promoter regions of many histone genes and that histone transcription is downregulated in a manner dependent on intracellular calcium levels. Indeed, overexpression of histone H3 markedly inhibited cell proliferation. Taken together, these findings suggest that NFATc1 prevents the detrimental effects of histone H3 accumulation by inhibiting expression of histone at the transcriptional level.
Topics: NFATC Transcription Factors; Histones; Calcineurin; Humans; Cell Proliferation; Gene Expression Regulation; Promoter Regions, Genetic; Signal Transduction; Transcription, Genetic; Calcium
PubMed: 38926604
DOI: 10.1038/s41598-024-65769-9 -
Cell Death & Disease Jun 2024Triple-negative breast cancer (TNBC) is a subtype of breast cancer that is prone to metastasis and therapy resistance. Owing to its aggressive nature and limited...
Triple-negative breast cancer (TNBC) is a subtype of breast cancer that is prone to metastasis and therapy resistance. Owing to its aggressive nature and limited availability of targeted therapies, TNBC is associated with higher mortality as compared to other forms of breast cancer. In order to develop new therapeutic options for TNBC, we characterized the factors involved in TNBC growth and progression. Here, we demonstrate that N-acylsphingosine amidohydrolase 1 (ASAH1) is overexpressed in TNBC cells and is regulated via p53 and PI3K-AKT signaling pathways. Genetic knockdown or pharmacological inhibition of ASAH1 suppresses TNBC growth and progression. Mechanistically, ASAH1 inhibition stimulates dual-specificity phosphatase 5 (DUSP5) expression, suppressing the mitogen-activated protein kinase (MAPK) pathway. Furthermore, pharmacological cotargeting of the ASAH1 and MAPK pathways inhibits TNBC growth. Collectively, we unmasked a novel role of ASAH1 in driving TNBC and identified dual targeting of the ASAH1 and MAPK pathways as a potential new therapeutic approach for TNBC treatment.
Topics: Humans; Triple Negative Breast Neoplasms; Acid Ceramidase; Dual-Specificity Phosphatases; Female; Cell Line, Tumor; MAP Kinase Signaling System; Cell Proliferation; Animals; Gene Expression Regulation, Neoplastic; Mice, Nude; Mice; Proto-Oncogene Proteins c-akt; Tumor Suppressor Protein p53; Phosphatidylinositol 3-Kinases; Signal Transduction
PubMed: 38926346
DOI: 10.1038/s41419-024-06831-2 -
Cells Jun 2024Resveratrol is a polyphenol known to have metabolic as well as circadian effects. However, there is little information regarding the metabolic and circadian effect of...
Resveratrol is a polyphenol known to have metabolic as well as circadian effects. However, there is little information regarding the metabolic and circadian effect of resveratrol on muscle cells. We sought to investigate the metabolic impact of resveratrol throughout the circadian cycle to clarify the associated signaling pathways. C2C12 myotubes were incubated with resveratrol in the presence of increasing concentrations of glucose, and metabolic and clock proteins were measured for 24 h. Resveratrol led to SIRT1, AMPK and PP2A activation. Myotubes treated with increasing glucose concentrations showed higher activation of the mTOR signaling pathway. However, resveratrol did not activate the mTOR signaling pathway, except for P70S6K and S6. In accordance with the reduced mTOR activity, resveratrol led to advanced circadian rhythms and reduced levels of pBMAL1 and CRY1. Resveratrol increased myogenin expression and advanced its rhythms. In conclusion, resveratrol activates the SIRT1-AMPK-PP2A axis, advances circadian rhythms and induces muscle development.
Topics: Resveratrol; Sirtuin 1; Animals; Mice; Muscle Fibers, Skeletal; Protein Phosphatase 2; AMP-Activated Protein Kinases; Circadian Rhythm; Signal Transduction; Cell Line; Glucose; Muscle Development; TOR Serine-Threonine Kinases
PubMed: 38920697
DOI: 10.3390/cells13121069 -
Nature Communications Jun 2024SDS22 forms an inactive complex with nascent protein phosphatase PP1 and Inhibitor-3. SDS22:PP1:Inhibitor-3 is a substrate for the ATPase p97/VCP, which liberates PP1...
SDS22 forms an inactive complex with nascent protein phosphatase PP1 and Inhibitor-3. SDS22:PP1:Inhibitor-3 is a substrate for the ATPase p97/VCP, which liberates PP1 for binding to canonical regulatory subunits. The exact role of SDS22 in PP1-holoenzyme assembly remains elusive. Here, we show that SDS22 stabilizes nascent PP1. In the absence of SDS22, PP1 is gradually lost, resulting in substrate hyperphosphorylation and a proliferation arrest. Similarly, we identify a female individual with a severe neurodevelopmental disorder bearing an unstable SDS22 mutant, associated with decreased PP1 levels. We furthermore find that SDS22 directly binds to Inhibitor-3 and that this is essential for the stable assembly of SDS22:PP1: Inhibitor-3, the recruitment of p97/VCP, and the extraction of SDS22 during holoenzyme assembly. SDS22 with a disabled Inhibitor-3 binding site co-transfers with PP1 to canonical regulatory subunits, thereby forming non-functional holoenzymes. Our data show that SDS22, through simultaneous interaction with PP1 and Inhibitor-3, integrates the major steps of PP1 holoenzyme assembly.
Topics: Protein Phosphatase 1; Humans; Holoenzymes; Female; Phosphorylation; Protein Binding; HEK293 Cells; Valosin Containing Protein
PubMed: 38918402
DOI: 10.1038/s41467-024-49746-4 -
Drug Design, Development and Therapy 2024Nepetoidin B (NB) has been reported to possess anti-inflammatory, antibacterial, and antioxidant properties. However, its effects on liver ischemia/reperfusion (I/R)...
BACKGROUND
Nepetoidin B (NB) has been reported to possess anti-inflammatory, antibacterial, and antioxidant properties. However, its effects on liver ischemia/reperfusion (I/R) injury remain unclear.
METHODS
In this study, a mouse liver I/R injury model and a mouse AML12 cell hypoxia reoxygenation (H/R) injury model were used to investigate the potential role of NB. Serum transaminase levels, liver necrotic area, cell viability, oxidative stress, inflammatory response, and apoptosis were evaluated to assess the effects of NB on liver I/R and cell H/R injury. Quantitative polymerase chain reaction (qPCR) and Western blotting were used to measure mRNA and protein expression levels, respectively. Molecular docking was used to predict the binding capacity of NB and mitogen-activated protein kinase phosphatase 5 (MKP5).
RESULTS
The results showed that NB significantly reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, liver necrosis, oxidative stress, reactive oxygen species (ROS) content, inflammatory cytokine content and expression, inflammatory cell infiltration, and apoptosis after liver I/R and AML12 cells H/R injury. Additionally, NB inhibited the JUN protein amino-terminal kinase (JNK)/P38 pathway. Molecular docking results showed good binding between NB and MKP5 proteins, and Western blotting results showed that NB increased the protein expression of MKP5. MKP5 knockout (KO) significantly diminished the protective effects of NB against liver injury and its inhibitory effects on the JNK/P38 pathway.
CONCLUSION
NB exerts hepatoprotective effects against liver I/R injury by regulating the MKP5-mediated P38/JNK signaling pathway.
Topics: Animals; Reperfusion Injury; Mice; Male; Mice, Inbred C57BL; p38 Mitogen-Activated Protein Kinases; Liver; Molecular Docking Simulation; Dual-Specificity Phosphatases; Dose-Response Relationship, Drug; MAP Kinase Signaling System; Structure-Activity Relationship; Disease Models, Animal; Molecular Structure; Oxidative Stress
PubMed: 38911032
DOI: 10.2147/DDDT.S457130 -
European Journal of Dermatology : EJD Apr 2024Previous studies reveal that psoriatic arthritis (PsA) and ankylosing spondylitis (AS) share susceptibility genes, such as HLA-B27, demonstrating a degree of genetic...
Previous studies reveal that psoriatic arthritis (PsA) and ankylosing spondylitis (AS) share susceptibility genes, such as HLA-B27, demonstrating a degree of genetic overlap between these diseases. Recent studies have identified a number of novel AS and PsA genetic susceptibility loci, but data on these loci in Chinese PsA patients are limited. To identify candidate genes that confer susceptibility to PsA in Chinese patients with PsA, psoriasis vulgaris (PsV), and healthy controls. Sixteen susceptibility loci, reported in a genome-wide association study of AS, and nine susceptibility loci, reported in candidate gene studies of PsA, were examined. Single-nucleotide polymorphisms (SNPs) were genotyped in 503 patients with PsA, 496 patients with PsV, and 979 healthy controls using the SNPscanTM multiplex SNP genotyping platform. PLINK software and logistic regression analysis were used to estimate the statistical significance of associations. PPP2R3C (rs8006884) was shown to significantly associate with PsA+PsV (p = 1.92×10-3, OR = 1.28) and was suggested to associate with PsV (p = 0.03, OR = 1.19). A suggestive association was also observed between IL-23R (rs12141575) and PsA as well as with axial PsA based on subtype analysis, KIF3A (rs2897442) and PsV, and ERN1 (rs196941) or IFIH1 (rs984971) and axial PsA. Our results suggest that PPP2R3C confers susceptibility to PsA and PsV, and that this gene may be related to the pathogenesis of psoriatic lesions and arthritis. Moreover, our results indicate a possible association between IL-23R, ERN1, or IFIH1 and subtypes of PsA, and between KIF3A and PsV.
Topics: Humans; Arthritis, Psoriatic; Spondylitis, Ankylosing; Male; Polymorphism, Single Nucleotide; Female; Genetic Predisposition to Disease; Asian People; Adult; Middle Aged; Case-Control Studies; China; Receptors, Interleukin; Protein Phosphatase 2; Genotype; Genome-Wide Association Study; Psoriasis; East Asian People
PubMed: 38907550
DOI: 10.1684/ejd.2024.4641