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1.
Adv Sci (Weinh) ; : e2308031, 2024 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-38493498

RESUMEN

Activated microglia in the retina are essential for the development of autoimmune uveitis. Yin-Yang 1 (YY1) is an important transcription factor that participates in multiple inflammatory and immune-mediated diseases. Here, an increased YY1 lactylation in retinal microglia within in the experimental autoimmune uveitis (EAU) group is observed. YY1 lactylation contributed to boosting microglial activation and promoting their proliferation and migration abilities. Inhibition of lactylation suppressed microglial activation and attenuated inflammation in EAU. Mechanistically, cleavage under targets & tagmentation ï¼ˆCUT&Tag) analysis revealed that YY1 lactylation promoted microglial activation by regulating the transcription of a set of inflammatory genes, including STAT3, CCL5, IRF1, IDO1, and SEMA4D. In addition, p300 is identified as the writer of YY1 lactylation. Inhibition of p300 decreased YY1 lactylation and suppressed microglial inflammation in vivo and in vitro. Collectively, the results showed that YY1 lactylation promoted microglial dysfunction in autoimmune uveitis by upregulating inflammatory cytokine secretion and boosting cell migration and proliferation. Therapeutic effects can be achieved by targeting the lactate/p300/YY1 lactylation/inflammatory genes axis.

2.
iScience ; 27(2): 109003, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38327792

RESUMEN

This study focused on examining the exact role of circulating immune cells in the development of diabetic retinopathy (DR). In vitro co-culture experiments showed that peripheral blood mononuclear cells (PBMCs) from patients with type 1 DR crucially modulated the biological functions of human retinal microvascular endothelial cells (HRMECs), consequently disrupting their normal functionality. Single-cell RNA sequencing (scRNA-seq) study revealed unique differentially expressed genes and pathways in circulating immune cells among healthy controls, non-diabetic retinopathy (NDR) patients, and DR patients. Of significance was the observed upregulation of JUND in each subset of PBMCs in patients with type 1 DR. Further studies showed that downregulating JUND in DR patient-derived PBMCs led to the amelioration of HRMEC dysfunction. These findings highlighted the notable alterations in the transcriptomic patterns of circulating immune cells in type 1 DR patients and underscored the significance of JUND as a key factor for PBMCs in participating in the pathogenesis of DR.

3.
Adv Sci (Weinh) ; 11(11): e2306563, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38168905

RESUMEN

Vogt-Koyanagi-Harada (VKH) disease is a severe autoimmune disease. Herein, whole-exome sequencing (WES) study are performed on 2,573 controls and 229 VKH patients with follow-up next-generation sequencing (NGS) in a collection of 2,380 controls and 2,278 VKH patients. A rare c.188T>C (p Val63Ala) variant in the olfactory receptor 11H1 (OR11H1) gene is found to be significantly associated with VKH disease (rs71235604, Pcombined = 7.83 × 10-30 , odds ratio = 3.12). Functional study showes that OR11H1-A63 significantly increased inflammatory factors production and exacerbated barrier function damage. Further studies using RNA-sequencing find that OR11H1-A63 markedly increased growth arrest and DNA-damage-inducible gamma (GADD45G) expression. Moreover, OR11H1-A63 activates the MAPK and NF-κB pathways, and accelerates inflammatory cascades. In addition, inhibiting GADD45G alleviates inflammatory factor secretion, likely due to the regulatory effect of GADD45G on the MAPK and NF-κB pathways. Collectively, this study suggests that the OR11H1-A63 missense mutation may increase susceptibility to VKH disease in a GADD45G-dependent manner.


Asunto(s)
Enfermedades Autoinmunes , Receptores Odorantes , Síndrome Uveomeningoencefálico , Humanos , Síndrome Uveomeningoencefálico/genética , Síndrome Uveomeningoencefálico/metabolismo , Receptores Odorantes/genética , FN-kappa B/genética , Mutación Missense/genética
4.
Adv Healthc Mater ; 13(12): e2303710, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38293743

RESUMEN

Diagnosing and treating liver fibrosis is a challenging yet crucial endeavor due to its complex pathogenesis and risk of deteriorating into cirrhosis, liver failure, and even hepatic cancer. Herein, a silica cross-linked micelles (SCLMs) based nano-system is developed for both diagnosing and treating liver fibrosis. The SCLMs are first modified with peptide CTCE9908 (CT-SCLMs) and can actively target CXCR4, which is overexpressed in activated hepatic stellate cells (HSCs). To enable diagnosis, an ONOO--responded near-infrared fluorescent probe NOF2 is loaded into the CT-SCLMs. This nano-system can target the aHSCs and diagnose the liver fibrosis particularly in CCl4-induced liver damage, by monitoring the reactive nitrogen species. Furthermore, a step is taken toward treatment by co-encapsulating two anti-fibrosis drugs, silibinin and sorafenib, within the CT-SCLMs. This combined approach results in a significant alleviation of liver injury. Symptoms associated with liver fibrosis, such as deposition of collagen, expression of hydroxyproline, and raised serological indicators show notable improvement. In summary, the CXCR4-targeted nano-system can serve as a promising theragnostic system of early warning and diagnosis for liver fibrosis, offering hope against progression of this serious liver condition.


Asunto(s)
Células Estrelladas Hepáticas , Cirrosis Hepática , Micelas , Nanomedicina , Cirrosis Hepática/metabolismo , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/patología , Cirrosis Hepática/diagnóstico , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/efectos de los fármacos , Animales , Nanomedicina/métodos , Humanos , Receptores CXCR4/metabolismo , Masculino , Diagnóstico Precoz , Ratones
5.
Curr Top Med Chem ; 24(3): 243-258, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38231069

RESUMEN

The Hedgehog (Hh) signaling pathway plays a crucial role in diverse biological processes such as cell differentiation, proliferation, senescence, tumorigenesis, malignant transformation, and drug resistance. Aberrant Hh signaling, resulting from mutations and excessive activation, can contribute to the development of various diseases during different stages of biogenesis and development. Moreover, it has been linked to unfavorable outcomes in several human cancers, including basal cell carcinoma (BCC), multiple myeloma (MM), melanoma, and breast cancer. Hence, the presence of mutations and excessive activation of the Hh pathway presents obstacles and constraints in the realm of cancer treatment. Extant research has demonstrated that small molecule inhibitors are regarded as the most effective therapeutic approaches for targeting the Hh pathway in contrast to traditional chemotherapy and radiotherapy. Consequently, this review focuses on the present repertoire of small molecule inhibitors that target various components of the Hh pathway, including Hh ligands, Ptch receptors, Smo transmembrane proteins, and Gli nuclear transcription factors. This study provides a comprehensive analysis of small molecules' structural and functional aspects in the preclinical and clinical management of cancer. Additionally, it elucidates the obstacles encountered in targeting the Hh pathway for human cancer therapy and proposes potential therapeutic approaches.


Asunto(s)
Antineoplásicos , Proteínas Hedgehog , Neoplasias , Transducción de Señal , Humanos , Proteínas Hedgehog/antagonistas & inhibidores , Proteínas Hedgehog/metabolismo , Transducción de Señal/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patología , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Animales
6.
Ocul Immunol Inflamm ; 32(3): 336-341, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36745681

RESUMEN

PURPOSE: To explore the association of the polymorphisms in PTPN6 and LncRNA C1RL-AS1 genes with ocular BD in Han Chinese patients. METHODS: Correlation study was performed using the iPLEX system on a cohort of ocular BD patients andcontrols. The genotyping of 7 SNPs for LncRNA C1RL-AS1 and PTPN6 genes in ocular BD patients was performed using the iPLEX Gold genotype. RESULTS: The frequencies of rs4013722 AG genotype/A allele in LncRNA C1RL-AS1 were significantly decreased in BD patients, and the frequency of GG genotype was significantly increased in BD patients. The rs4013722 was associated with ocular BD in male patients, but not in female patients. The AG and GG genotype of rs4013722 were associated with skin lesions in male patients. The gene polymorphisms of PTPN6 were not associated with BD patients. CONCLUSIONS: The LncRNA C1RL-AS1/rs4013722 polymorphism conferred susceptibility to ocular BD in Han Chinese patients, which was influenced by sex.Abbreviations: LncRNA: Long Non-coding RNA; BD: Behcet's disease; SNP: single nucleotide polymorphism; PBMCs: peripheral blood mononuclear cells; PTPs: Protein tyrosine phosphatases; PTPN6: protein tyrosine phosphatase non-receptor 6; GWAS: genome-wide association study; HWE: Hardy-Weinberg equilibrium; LD: linkage disequilibrium; OR: odds ratio; CI: confidence interval; eQTL: expression quantitative trait loci; IBD: inflammatory bowel disease; RA: rheumatoid arthritis; Padj: Bonferroni corrected P value; NS: non-significant.


Asunto(s)
Síndrome de Behçet , ARN Largo no Codificante , Humanos , Masculino , Femenino , ARN Largo no Codificante/genética , Síndrome de Behçet/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Leucocitos Mononucleares , Genotipo , Polimorfismo de Nucleótido Simple , China/epidemiología , Frecuencia de los Genes , Estudios de Casos y Controles , Proteína Tirosina Fosfatasa no Receptora Tipo 6/genética , Serina Endopeptidasas/genética
7.
Sci Adv ; 9(42): eadh4655, 2023 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-37851814

RESUMEN

Dysregulation of CD4+ T cell differentiation is linked to autoimmune diseases. Metabolic reprogramming from oxidative phosphorylation to glycolysis and accumulation of lactate are involved in this process. However, the underlying mechanisms remain unclear. Our study showed that lactate-derived lactylation regulated CD4+ T cell differentiation. Lactylation levels in CD4+ T cells increased with the progression of experimental autoimmune uveitis (EAU). Inhibition of lactylation suppressed TH17 differentiation and attenuated EAU inflammation. The global lactylome revealed the landscape of lactylated sites and proteins in the CD4+ T cells of normal and EAU mice. Specifically, hyperlactylation of Ikzf1 at Lys164 promoted TH17 differentiation by directly modulating the expression of TH17-related genes, including Runx1, Tlr4, interleukin-2 (IL-2), and IL-4. Delactylation of Ikzf1 at Lys164 impaired TH17 differentiation. These findings exemplify how glycolysis regulates the site specificity of protein lactylation to promote TH17 differentiation and implicate Ikzf1 lactylation as a potential therapeutic target for autoimmune diseases.


Asunto(s)
Enfermedades Autoinmunes , Uveítis , Ratones , Animales , Células Th17 , Uveítis/genética , Uveítis/tratamiento farmacológico , Enfermedades Autoinmunes/genética , Diferenciación Celular , Lactatos , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL
8.
Cell Mol Immunol ; 20(11): 1379-1392, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37828081

RESUMEN

Vogt-Koyanagi-Harada (VKH) disease is a leading cause of blindness in young and middle-aged people. However, the etiology of VKH disease remains unclear. Here, we performed the first trio-based whole-exome sequencing study, which enrolled 25 VKH patients and 50 controls, followed by a study of 2081 VKH patients from a Han Chinese population to uncover detrimental mutations. A total of 15 de novo mutations in VKH patients were identified, with one of the most important being the membrane palmitoylated protein 2 (MPP2) p.K315N (MPP2-N315) mutation. The MPP2-N315 mutation was highly deleterious according to bioinformatic predictions. Additionally, this mutation appears rare, being absent from the 1000 Genome Project and Genome Aggregation Database, and it is highly conserved in 10 species, including humans and mice. Subsequent studies showed that pathological phenotypes and retinal vascular leakage were aggravated in MPP2-N315 mutation knock-in or MPP2-N315 adeno-associated virus-treated mice with experimental autoimmune uveitis (EAU). In vitro, we used clustered regularly interspaced short palindromic repeats (CRISPR‒Cas9) gene editing technology to delete intrinsic MPP2 before overexpressing wild-type MPP2 or MPP2-N315. Levels of cytokines, such as IL-1ß, IL-17E, and vascular endothelial growth factor A, were increased, and barrier function was destroyed in the MPP2-N315 mutant ARPE19 cells. Mechanistically, the MPP2-N315 mutation had a stronger ability to directly bind to ANXA2 than MPP2-K315, as shown by LC‒MS/MS and Co-IP, and resulted in activation of the ERK3/IL-17E pathway. Overall, our results demonstrated that the MPP2-K315N mutation may increase susceptibility to VKH disease.


Asunto(s)
Síndrome Uveomeningoencefálico , Animales , Humanos , Ratones , Persona de Mediana Edad , Cromatografía Liquida , Secuenciación del Exoma , Interleucina-17/genética , Mutación Missense , Espectrometría de Masas en Tándem , Síndrome Uveomeningoencefálico/genética , Síndrome Uveomeningoencefálico/epidemiología , Factor A de Crecimiento Endotelial Vascular
9.
J Clin Neurosci ; 116: 112-119, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37688929

RESUMEN

OBJECTIVE: Diabetic retinopathy (DR) is a microvascular complication of diabetes that occurs at high frequencies (more than 20%) during the course of the disease. Therefore, we conducted a meta-analysis of the incidence of stroke in DR to determine whether DR is associated with stroke. METHODS: The PubMed, Embase and Cochrane databases were systematically searched from their inception to December 1, 2022. Randomized controlled trials (RCTs) that reported DR and stroke events were included. The pooled risk ratio and 95% confidence interval (CI) were calculated. For the incidences of DR and stroke, risk difference and standard error were measured. Sensitivity analysis was performed to assess whether any single study could affect the overall outcome. RESULTS: Nine RCTs involving 46,599 patients with diabetes were included in this meta-analysis. The incidence of DR in all patients was 0.29 (95% CI 0.20-0.38). The incidence of any stroke in all patients was 0.03 (95% CI 0.03-0.04). The incidence of any stroke in patients with DR was 0.05 (95% CI 0.04-0.07), significant higher than that in all diabetes patients. The pooled risk ratio of stroke in patients with DR was 2.04 (95% CI 1.25-3.32). The estimated risk ratio of stroke in patients with DR without additional conditions was 1.70 (95% CI 1.43-2.03), which was lower than that in patients with DR with additional conditions (2.29, 95% CI 0.93-5.65). CONCLUSION: The presence of DR is associated with an increased risk of stroke. Our findings indicate that DR is an important biomarker for the prediction of stroke, and periodic eye examinations should be conducted for stroke prevention.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Accidente Cerebrovascular , Humanos , Retinopatía Diabética/epidemiología , Retinopatía Diabética/etiología , Bases de Datos Factuales , Oportunidad Relativa , Pacientes , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/epidemiología
10.
Eur J Pharmacol ; 957: 175996, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37597646

RESUMEN

BACKGROUND: Frizzled 6 (Fzd6) is involved in the development of various disorders; however, its role in the etiology of depression remains unclear. We aimed to determine the potential regulatory mechanisms of Fzd6 as a Wnt receptor in depression. METHODS: Mice were divided into four groups: wild-type control (Fzd6WT-control), Fzd6 mutant control (Fzd6Q152E-control), wild-type reserpine (Fzd6WT-reserpine), and Fzd6 mutant reserpine (Fzd6Q152E-reserpine). Reserpine (0.5 mg/kg) was injected intraperitoneally for 10 days. Four behavioral experiments were performed to assess the effects of Fzd6Q152E on depression-like behaviors in the reserpine-treated mice. Blood samples were collected for an enzyme-linked immunosorbent assay (ELISA). Gene expression in the hippocampus was quantified using quantitative real-time polymerase chain reaction (qRT-PCR), and protein expression levels in the hippocampus were identified using western blotting. RESULTS: The Fzd6 mutation affected reserpine-induced depression-like behavioral changes in mice. ELISA revealed significantly reduced serum levels of 5-hydroxytryptamine (5-HT), brain-derived neurotrophic factor (BDNF), and norepinephrine in both Fzd6Q152E-reserpine and Fzd6WT-reserpine mice, with a more pronounced decrease in Fzd6Q152E-reserpine mice, especially in norepinephrine expression. The qRT-PCR results showed significantly decreased Fzd6 expression in Fzd6Q152E-reserpine mice and altered expression of Dkk2, Gsk-3ß, Lrp6, Wnt2, Wnt3, and Wnt3a in the Wnt pathway. Western blotting revealed decreased Fzd6 protein expression in Fzd6Q152E-control mice compared to Fzd6WT-control mice, whereas Fzd6 protein expression was restored in Fzd6Q152E-reserpine mice, and Gsk-3ß expression was significantly changed. CONCLUSION: Fzd6 potentially influences reserpine-induced depressive behavioral changes and serum depressive factor alterations and modulates the expression of the Wnt signaling pathway in the hippocampus of depressed mice.


Asunto(s)
Depresión , Vía de Señalización Wnt , Animales , Ratones , Depresión/inducido químicamente , Depresión/genética , Glucógeno Sintasa Quinasa 3 beta , Reserpina , Mutación , Norepinefrina , Serotonina
11.
Genes Dis ; 10(5): 2179-2193, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37492748

RESUMEN

Uveitis, a vision-threatening inflammatory disease worldwide, is closely related to resident microglia. Retinal microglia are the main immune effector cells with strong plasticity, but their role in uveitis remains unclear. N6-methyladenosine (m6A) modification has been proven to be involved in the immune response. Therefore, we in this work aimed to identify the potentially crucial m6A regulators of microglia in uveitis. Through the single-cell sequencing (scRNA-seq) analysis and experimental verification, we found a significant decrease in the expression of fat mass and obesity-associated protein (FTO) in retinal microglia of uveitis mice and human microglia clone 3 (HMC3) cells with inflammation. Additionally, FTO knockdown was found to aggravate the secretion of inflammatory factors and the mobility/chemotaxis of microglia. Mechanistically, the RNA-seq data and rescue experiments showed that glypican 4 (GPC4) was the target of FTO, which regulated microglial inflammation mediated by the TLR4/NF-κB pathway. Moreover, RNA stability assays indicated that GPC4 upregulation was mainly regulated by the downregulation of the m6A "reader" YTH domain family protein 3 (YTHDF3). Finally, the FTO inhibitor FB23-2 further exacerbated experimental autoimmune uveitis (EAU) inflammation by promoting the GPC4/TLR4/NF-κB signaling axis, and this could be attenuated by the TLR4 inhibitor TAK-242. Collectively, a decreased FTO could facilitate microglial inflammation in EAU, suggesting that the restoration or activation of FTO function may be a potential therapeutic strategy for uveitis.

12.
BMC Ophthalmol ; 23(1): 252, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37277716

RESUMEN

BACKGROUND: Primary Sjögren's syndrome (pSS) is a chronic autoimmune disorder defined by xerostomia and keratoconjunctivitis sicca, and its etiology remains unknown. N6-methyladenosine (m6A) is the predominant posttranscriptional modification in eukaryotic mRNAs and is dynamically regulated by m6A regulators. Dysregulation of m6A modification is closely associated with several autoimmune disorders, but the role of m6A modification in pSS remains unknown. This study investigated the potential role of m6A and m6A-related regulators in pSS patients with dry eye. METHODS: This cross-sectional study included forty-eight pSS patients with dry eye and forty healthy controls (HCs). Peripheral blood mononuclear cells (PBMCs) were isolated, and the level of m6A in total RNA was measured. The expression of m6A regulators was determined utilizing real-time PCR and western blotting. The serological indicators detected included autoantibodies, immunoglobulins (Igs), complement factors (Cs), and inflammatory indicators. Dry eye symptoms and signs were measured, including the ocular surface disease index, Schirmer's test (ST), corneal fluorescein staining score (CFS), and tear break-up time. Spearman's correlation coefficient was employed to assess the associations of m6A and m6A-related regulator expression with clinical characteristics. RESULTS: The expression level of m6A was markedly increased in the PBMCs of pSS patients with dry eye compared to HCs (P value<0.001). The relative mRNA and protein expression levels of the m6A regulators methyltransferase-like 3 (METTL3) and YT521-B homology domains 1 were markedly elevated in pSS patients with dry eye (both P value<0.01). The m6A RNA level was found to be positively related to METTL3 expression in pSS patients (r = 0.793, P value<0.001). Both the m6A RNA level and METTL3 mRNA expression correlated with the anti-SSB antibody, IgG, ST, and CFS (all P values < 0.05). The m6A RNA level was associated with C4 (r = -0.432, P value = 0.002), while METTL3 mRNA expression was associated with C3 (r = -0.313, P value = 0.030). CONCLUSIONS: Our work revealed that the upregulation of m6A and METTL3 was associated with the performance of serological indicators and dry eye signs in pSS patients with dry eye. METTL3 may contribute to the pathogenesis of dry eye related to pSS.


Asunto(s)
Síndromes de Ojo Seco , Síndrome de Sjögren , Humanos , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/genética , Metilación , Estudios Transversales , Leucocitos Mononucleares/patología , Síndromes de Ojo Seco/etiología , Síndromes de Ojo Seco/patología , ARN/genética , Metiltransferasas
13.
Invest Ophthalmol Vis Sci ; 64(5): 21, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37219511

RESUMEN

Purpose: Apigenin is a natural small molecule compound widely present in various vegetables and fruits. Recently, Apigenin was reported to inhibit lipopolysaccharide (LPS)-simulated microglial proinflammatory activation. Considering the important role of microglia in retinal disorders, we wonder whether Apigenin could exert a therapeutic effect on experimental autoimmune uveitis (EAU) through reprogramming retinal microglia to a beneficial subtype. Methods: EAU was induced in C57BL/6J mice by immunization with interphotoreceptor retinoid-binding protein (IRBP)651-670, followed by intraperitoneal administration of Apigenin. Disease severity was assessed based on clinical and pathological scores. In vivo, Western blotting was used to quantify protein levels of classical inflammatory factors, microglial M1/M2 markers and the tight junction protein of the blood-retinal-barrier (BRB). Immunofluorescence was used to determine the Apigenin's efficacy on microglial phenotype. In vitro, Apigenin was added in LPS and IFN-γ stimulated human microglial cell line. Western blotting and Transwell assays were used to analyze the phenotype of microglia. Results: In vivo, we found that Apigenin significantly reduced the clinical and pathological scores of EAU. The protein levels of inflammatory cytokines were significantly decreased in retina, and BRB disruption was ameliorated after Apigenin treatment. Meanwhile, Apigenin inhibited microglia M1 transition in EAU mice retina. In vitro functional studies showed that Apigenin decreased LPS and IFN-γ-induced microglial inflammatory factor production and M1-activation via the TLR4/MyD88 pathway. Conclusions: Apigenin can ameliorate retinal inflammation in IRBP induced autoimmune uveitis through inhibiting microglia M1 pro-inflammatory polarization via TLR4/MyD88 pathway.


Asunto(s)
Microglía , Uveítis , Ratones , Humanos , Animales , Ratones Endogámicos C57BL , Apigenina , Lipopolisacáridos , Factor 88 de Diferenciación Mieloide , Receptor Toll-Like 4
14.
Comput Struct Biotechnol J ; 21: 2365-2372, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37066123

RESUMEN

The chemical identification of the modified heme (the green heme) during chloroperoxidase catalyzed epoxidation of allylbenzene remains unestablished due to its high instability within the protein matrix, the absence of paramagnetically shifted signals, and the difficulty in obtaining crystals of the modified enzyme. We have established the unambiguous structure of the modified prosthetic heme group, which was extracted from the protein matrix using 2D NMR spectroscopy and LC-MS spectrometry. The modified heme was isolated as a µ-oxo dimer that can be quantitatively converted to the corresponding monomer. The depolymerized green heme displayed characteristic NMR signatures of iron porphyrin complexes, but no Nuclear Overhauser Effect was observable to assist in signal assignment. An alternative strategy was applied by removing the iron center of the green heme, resulting in a stable demetallated green porphyrin species. Complete assignment of all the NMR resonances in the demetallated green heme allowed us to establish the molecular architecture of the modified species as a novel N-alkylated heme. Decisive space correlations between the propyl protons of allylbenzene and the γ meso proton coupled with clear dipolar connectivities between the propyl-2H of the substrate and the ß proton in the side chain of the propionic acid at carbon-6 of the porphyrin ring, clearly indicate that allylbenzene was covalently attached to the nitrogen atom of the pyrrole ring III of the prosthetic heme. In this study, the mechanism of green CPO formation and its relation to CPO catalyzed chiral transformations are also discussed. It is concluded that the double-phenyl clamp formed by two phenylalanine residues at the distal heme pocket plays a critical role in fine-tuning substrate orientation that determines the outcome of CPO catalyzed epoxidation of substituted styrenes.

15.
Adv Sci (Weinh) ; 10(16): e2206623, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37017569

RESUMEN

The underlying mechanisms that determine gene expression and chromatin accessibility in retinogenesis are poorly understood. Herein, single-cell RNA sequencing and single-cell assay for transposase-accessible chromatin sequencing are performed on human embryonic eye samples obtained 9-26 weeks after conception to explore the heterogeneity of retinal progenitor cells (RPCs) and neurogenic RPCs. The differentiation trajectory from RPCs to 7 major types of retinal cells are verified. Subsequently, diverse lineage-determining transcription factors are identified and their gene regulatory networks are refined at the transcriptomic and epigenomic levels. Treatment of retinospheres, with the inhibitor of RE1 silencing transcription factor, X5050, induces more neurogenesis with the regular arrangement, and a decrease in Müller glial cells. The signatures of major retinal cells and their correlation with pathogenic genes associated with multiple ocular diseases, including uveitis and age-related macular degeneration are also described. A framework for the integrated exploration of single-cell developmental dynamics of the human primary retina is provided.


Asunto(s)
Epigenómica , Transcriptoma , Humanos , Transcriptoma/genética , Retina/metabolismo , Neurogénesis , Cromatina/genética
16.
Genome Biol ; 24(1): 87, 2023 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-37085894

RESUMEN

BACKGROUND: Ocular neovascularization is a leading cause of blindness. Retinal microglia have been implicated in hypoxia-induced angiogenesis and vasculopathy, but the underlying mechanisms are not entirely clear. Lactylation is a novel lactate-derived posttranslational modification that plays key roles in multiple cellular processes. Since hypoxia in ischemic retinopathy is a precipitating factor for retinal neovascularization, lactylation is very likely to be involved in this process. The present study aimed to explore the role of lactylation in retinal neovascularization and identify new therapeutic targets for retinal neovascular diseases. RESULTS: Microglial depletion by the colony-stimulating factor 1 receptor (CSF1R) inhibitor PLX3397 suppresses retinal neovascularization in oxygen-induced retinopathy. Hypoxia increased lactylation in microglia and accelerates FGF2 expression, promoting retinal neovascularization. We identify 77 sites of 67 proteins with increased lactylation in the context of increased lactate under hypoxia. Our results show that the nonhistone protein Yin Yang-1 (YY1), a transcription factor, is lactylated at lysine 183 (K183), which is regulated by p300. Hyperlactylated YY1 directly enhances FGF2 transcription and promotes angiogenesis. YY1 mutation at K183 eliminates these effects. Overexpression of p300 increases YY1 lactylation and enhances angiogenesis in vitro and administration of the p300 inhibitor A485 greatly suppresses vascularization in vivo and in vitro. CONCLUSIONS: Our results suggest that YY1 lactylation in microglia plays an important role in retinal neovascularization by upregulating FGF2 expression. Targeting the lactate/p300/YY1 lactylation/FGF2 axis may provide new therapeutic targets for proliferative retinopathies.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos , Microglía , Neovascularización Retiniana , Factor de Transcripción YY1 , Animales , Ratones , Factor 2 de Crecimiento de Fibroblastos/farmacología , Hipoxia/metabolismo , Lactatos/metabolismo , Lactatos/farmacología , Microglía/metabolismo , Procesamiento Proteico-Postraduccional , Neovascularización Retiniana/genética , Neovascularización Retiniana/metabolismo , Activación Transcripcional , Regulación hacia Arriba , Factor de Transcripción YY1/genética , Factor de Transcripción YY1/metabolismo
17.
BMC Cancer ; 23(1): 162, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36800936

RESUMEN

BACKGROUND: Oral squamous cell carcinoma (OSCC) is a common malignant tumor associated with poor prognosis. MicroRNAs (miRNAs) play crucial regulatory roles in the cancer development. However, the role of miRNAs in OSCC development and progression is not well understood. METHODS: We sought to establish a dynamic Chinese hamster OSCC animal model, construct miRNA differential expression profiles of its occurrence and development, predict its targets, and perform functional analysis and validation in vitro. RESULTS: Using expression and functional analyses, the key candidate miRNA (miR-181a-5p) was selected for further functional research, and the expression of miR-181a-5p in OSCC tissues and cell lines was detected. Subsequently, transfection technology and a nude mouse tumorigenic model were used to explore potential molecular mechanisms. miR-181a-5p was significantly downregulated in human OSCC specimens and cell lines, and decreased miR-181a-5p expression was observed in multiple stages of the Chinese hamster OSCC animal model. Moreover, upregulated miR-181a-5p significantly inhibited OSCC cell proliferation, colony formation, invasion, and migration; blocked the cell cycle; and promoted apoptosis. BCL2 was identified as a target of miR-181a-5p. BCL2 may interact with apoptosis- (BAX), invasion- and migration- (TIMP1, MMP2, and MMP9), and cell cycle-related genes (KI67, E2F1, CYCLIND1, and CDK6) to further regulate biological behavior. Tumor xenograft analysis indicated that tumor growth was significantly inhibited in the high miR-181a-5p expression group. CONCLUSION: Our findings indicate that miR-181a-5p can be used as a potential biomarker and provide a novel animal model for mechanistic research on oral cancer.


Asunto(s)
MicroARNs , Neoplasias de la Boca , Carcinoma de Células Escamosas de Cabeza y Cuello , Animales , Cricetinae , Humanos , Ratones , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Cricetulus , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias de la Boca/patología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo
18.
Seizure ; 106: 110-116, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36827862

RESUMEN

BACKGROUND AND PURPOSE: This study aimed to characterize the clinical features of epilepsy in mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) and analyze the clinical determinants for drug-resistant epilepsy in MELAS. METHODS: A single-center, retrospective study was conducted to investigate the clinical features of epilepsy in patients with MELAS. Collected variables included seizure semiology, electroencephalography (EEG), muscle biopsy, genetic testing, neuroimaging findings, resting serum lactic value and modified Rankin scale (mRS) of patients with MELAS. We also investigated the differences between the adult-onset group and the child-onset group and analyzed the risk factors for drug-resistant epilepsy in MELAS. RESULTS: We studied 97 patients (56 males: 41 females) with confirmed MELAS. Epileptic seizure occurred in 100.0% of patients and the initial symptom of 69.1% patients was epileptic seizure. The average age of disease onset was 21.0 years, ranging from 2 to 60 years. The seizure types of these patients with MELAS were variable, with generalized onset (51.5%) to be the most common type. The EEG changes in the patients with MELAS were mainly slow wave (90.9%) and epileptiform discharge (68.2%). The child-onset group with earlier seizure onset presented significantly higher resting serum lactic value (p = 0.0048) and lower incidence of stroke-like lesion in the brain (p = 0.003), especially in the temporal lobe (p < 0.001), compared with the adult-onset group. Importantly, drug-resistant epilepsy in MELAS was demonstrated to be closely related to the earlier age of seizure onset (p = 0.013), as well as the higher mRS score (p < 0.001) and higher resting serum lactic value (p = 0.009). CONCLUSION: Early identification of MELAS should be considered among individuals with recurrent epilepsy through clinical screening. Age of seizure onset and resting serum lactic value may predict the development of drug-resistant epilepsy in MELAS. Close observation and appropriate anti-epileptic treatment are indispensable for individuals with MELAS to improve the prognosis. Further studies with larger sample size are required to further evaluate the risk factors of drug-resistant epilepsy in MELAS and provide guidance on treatment of MELAS.


Asunto(s)
Epilepsia , Síndrome MELAS , Accidente Cerebrovascular , Adulto , Masculino , Femenino , Humanos , Adulto Joven , Síndrome MELAS/complicaciones , Estudios Retrospectivos , Convulsiones/etiología
19.
Clin Immunol ; 246: 109205, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36509389

RESUMEN

Vogt-Koyanagi-Harada (VKH) disease, a major blinding eye disease, is characterized by an autoimmune response against melanocytes in multiple organs throughout the body. Currently, the aetiology and pathogenesis of VKH disease are unclear, and the treatment strategy needs to be further optimized. The retinal pigment epithelium (RPE), a monolayer of pigmented cells of the fundus, is essential for maintaining normal visual function and is involved in both the acute and chronic stages of VKH disease. Therefore, the functions of the RPE may play a critical role in the aetiology and treatment of VKH disease. Herein, we established a human induced pluripotent stem cell (hiPSC) RPE model of VKH disease by reprogramming peripheral blood mononuclear cells (PBMCs) into iPSCs and then differentiating them into RPE cells. Patient-derived RPE cells exhibited barrier disruption, impaired phagocytosis, and depigmentation compared with those from normal controls, which was consistent with the features of VKH disease. Furthermore, a small molecular compound targeting EGR2 was found to rescue the barrier and phagocytic functions of the hiPSC-RPE cells through high-throughput virtual screening and functional studies, suggesting a promising strategy for the treatment of VKH disease.


Asunto(s)
Células Madre Pluripotentes Inducidas , Síndrome Uveomeningoencefálico , Humanos , Síndrome Uveomeningoencefálico/tratamiento farmacológico , Evaluación Preclínica de Medicamentos , Leucocitos Mononucleares , Epitelio Pigmentado de la Retina
20.
MedComm (2020) ; 4(1): e198, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36582303

RESUMEN

Stem cell therapy is a promising strategy to rescue visual impairment caused by retinal degeneration. Previous studies have proposed controversial theories about whether in situ retinal stem cells (RSCs) are present in adult human eye tissue. Single-cell RNA sequencing (scRNA-seq) has emerged as one of the most powerful tools to reveal the heterogeneity of tissue cells. By using scRNA-seq, we explored the cell heterogeneity of different subregions of adult human eyes, including pars plicata, pars plana, retinal pigment epithelium (RPE), iris, and neural retina (NR). We identified one subpopulation expressing SRY-box transcription factor 2 (SOX2) as RSCs, which were present in the pars plicata of the adult human eye. Further analysis showed the identified subpopulation of RSCs expressed specific markers aquaporin 1 (AQP1) and tetraspanin 12 (TSPAN12). We, therefore, isolated this subpopulation using these two markers by flow sorting and found that the isolated RSCs could proliferate and differentiate into some retinal cell types, including photoreceptors, neurons, RPE cells, microglia, astrocytes, horizontal cells, bipolar cells, and ganglion cells; whereas, AQP1- TSPAN12- cells did not have this differentiation potential. In conclusion, our results showed that SOX2-positive RSCs are present in the pars plicata and may be valuable for treating human retinal diseases due to their proliferation and differentiation potential.

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