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1.
Front Neurol ; 15: 1440995, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39170074

RESUMO

Background: Migraine risk factors are associated with migraine susceptibility, yet their mechanisms are unclear. Evidence suggests a role for inflammatory proteins and immune cells in migraine pathogenesis. This study aimed to examine the inflammo-immune association between eight migraine risk factors and the disorder. Methods: This study utilized inverse variance weighted (IVW) method and colocalization analysis to explore potential causal relationships between eight migraine risk factors, migraine, 731 immune cells, and 91 circulating inflammatory proteins. Mediation Mendelian randomization (MR) was further used to confirm the mediating role of circulating inflammatory proteins and immune cells between the eight migraine risk factors and migraine. Results: Migraine risk factors are linked to 276 immune cells and inflammatory proteins, with cigarettes smoked per day strongly co-localized with CD33-HLA DR+ cells. Despite no co-localization, 23 immune cells/inflammatory proteins relate to migraine. Depression, all anxiety disorders, and sleep apnea are correlated with migraine, and all anxiety disorders are supported by strong co-localization evidence. However, the mediating effect of inflammatory proteins and immune cells between eight migraine risk factors and migraine has not been confirmed. Conclusion: We elucidate the potential causal relationships between eight migraine risk factors, migraine, immune cells, and inflammatory proteins, enhancing our understanding of the molecular etiology of migraine pathogenesis from an inflammatory-immune perspective.

2.
Org Lett ; 26(20): 4388-4393, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38752694

RESUMO

Herein, a photoredox-driven practical protocol for fluorinated alkene synthesis using easily accessible and modular thianthrenium salts with electron-withdrawing alkynes or propargyl alcohols is reported. Vinyl radical intermediates, formed by the reaction between the alkyl or trifluoromethyl thianthrenium salts and electronically diverse alkynes, can mediate the key 1,5-HAT process of regioselective C(sp3)-H fluorination and vinylation. This protocol provides straightforward access to structurally diverse trifluoromethyl- or distally fluoro-functionalized alkene products in 21-79% yields with a broad substrate range under mild photocatalytic conditions.

3.
Proc Natl Acad Sci U S A ; 121(21): e2401079121, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38739800

RESUMO

Homomeric dimerization of metabotropic glutamate receptors (mGlus) is essential for the modulation of their functions and represents a promising avenue for the development of novel therapeutic approaches to address central nervous system diseases. Yet, the scarcity of detailed molecular and energetic data on mGlu2 impedes our in-depth comprehension of their activation process. Here, we employ computational simulation methods to elucidate the activation process and key events associated with the mGlu2, including a detailed analysis of its conformational transitions, the binding of agonists, Gi protein coupling, and the guanosine diphosphate (GDP) release. Our results demonstrate that the activation of mGlu2 is a stepwise process and several energy barriers need to be overcome. Moreover, we also identify the rate-determining step of the mGlu2's transition from the agonist-bound state to its active state. From the perspective of free-energy analysis, we find that the conformational dynamics of mGlu2's subunit follow coupled rather than discrete, independent actions. Asymmetric dimerization is critical for receptor activation. Our calculation results are consistent with the observation of cross-linking and fluorescent-labeled blot experiments, thus illustrating the reliability of our calculations. Besides, we also identify potential key residues in the Gi protein binding position on mGlu2, mGlu2 dimer's TM6-TM6 interface, and Gi α5 helix by the change of energy barriers after mutation. The implications of our findings could lead to a more comprehensive grasp of class C G protein-coupled receptor activation.


Assuntos
Receptores de Glutamato Metabotrópico , Receptores de Glutamato Metabotrópico/metabolismo , Receptores de Glutamato Metabotrópico/química , Humanos , Multimerização Proteica , Simulação de Dinâmica Molecular , Conformação Proteica , Ligação Proteica
4.
Front Pharmacol ; 15: 1360835, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655181

RESUMO

Aims: The formation of anti-drug antibodies (ADAs) during anti-tumor necrosis factor (anti-TNF) therapy is reported to lead to reducing serum drug levels, which may bring about a loss of response to treatment. Previous research has suggested an association between specific antibiotic classes and ADA formation during anti-TNF therapy. However, there are few studies specifically examining this association in Chinese inflammatory bowel disease (IBD) patients. Therefore, our study aimed to evaluate the possible effect of antibiotic use on ADA formation to anti-TNF therapy in Chinese patients with IBD. Methods: A total of 166 patients with IBD, including 149 with Crohn's disease (CD) and 17 with ulcerative colitis (UC), were included in this retrospective analysis. These patients were initially treated with anti-TNF therapy (infliximab or adalimumab) after January 2018 and reviewed with available ADA levels before October 2023. After univariable analysis of all the variables, a multivariate Cox proportional hazards model was used to assess the association between antibiotic use and ADA development. Results: Among 166 IBD patients treated with infliximab (108/166, 65.1%) or adalimumab (58/166, 34.9%), 31 patients (18.7%) were measured as positive ADA levels. Cox proportional hazard model demonstrated an increased risk of ADA formation in IBD patients who used ß-lactam-ß-lactamase inhibitor combinations (BL-BLIs) (HR = 5.143, 95%CI 1.136-23.270, p = 0.033), or nitroimidazoles (HR = 4.635, 95%CI 1.641-13.089, p = 0.004) during 12 months before the ADA test. On the contrary, a reduced risk was noted in patients treated with fluoroquinolones (HR = 0.258, 95% CI 0.072-0.924, p = 0.037). Moreover, the median serum infliximab or adalimumab concentration in patients with positive ADA levels was significantly lower than that in patients with negative ADA levels (infliximab: 0.30 vs. 1.85 µg/mL, p < 0.0001; adalimumab: 0.45 vs. 7.55 µg/mL, p = 0.0121). Conclusion: ADA development is associated with various antibiotic classes. BL-BLIs and nitroimidazoles might increase the risk of ADA formation during anti-TNF therapy in Chinese IBD patients, while the treatment with fluoroquinolones could probably reduce such risk. There were certain limitations in the retrospective analysis of the study, therefore, the results are just for reference, and other studies are needed to further confirm our findings.

5.
Proteins ; 92(6): 705-719, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38183172

RESUMO

The omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) characterized by 30 mutations in its spike protein, has rapidly spread worldwide since November 2021, significantly exacerbating the ongoing COVID-19 pandemic. In order to investigate the relationship between these mutations and the variant's high transmissibility, we conducted a systematic analysis of the mutational effect on spike-angiotensin-converting enzyme-2 (ACE2) interactions and explored the structural/energy correlation of key mutations, utilizing a reliable coarse-grained model. Our study extended beyond the receptor-binding domain (RBD) of spike trimer through comprehensive modeling of the full-length spike trimer rather than just the RBD. Our free-energy calculation revealed that the enhanced binding affinity between the spike protein and the ACE2 receptor is correlated with the increased structural stability of the isolated spike protein, thus explaining the omicron variant's heightened transmissibility. The conclusion was supported by our experimental analyses involving the expression and purification of the full-length spike trimer. Furthermore, the energy decomposition analysis established those electrostatic interactions make major contributions to this effect. We categorized the mutations into four groups and established an analytical framework that can be employed in studying future mutations. Additionally, our calculations rationalized the reduced affinity of the omicron variant towards most available therapeutic neutralizing antibodies, when compared with the wild type. By providing concrete experimental data and offering a solid explanation, this study contributes to a better understanding of the relationship between theories and observations and lays the foundation for future investigations.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Mutação , Ligação Proteica , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/química , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , COVID-19/virologia , COVID-19/transmissão , Humanos , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/química , Simulação de Dinâmica Molecular , Termodinâmica , Modelos Moleculares
6.
J Clin Microbiol ; 62(2): e0139623, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38259071

RESUMO

Chemokine receptor 4 (CXCR4) plays a vital role in immunoregulation during hepatitis B virus (HBV) infection. This study aimed to screen single-nucleotide polymorphisms (SNPs) of CXCR4 for predicting pegylated interferon-alpha (PegIFNα) therapy response in chronic hepatitis B (CHB) patients. This retrospective cohort study enrolled a total of 945 CHB patients in two cohorts (Cohort 1, n = 238; Cohort 2, n = 707), and all the patients were hepatitis B e antigen (HBeAg)-positive and treated with PegIFNα for 48 weeks and followed up for 24 weeks. Twenty-two tag SNPs were selected in CXCR4 and its flanking region. A polygenic score (PGS) was utilized to evaluate the cumulative effect of multiple SNPs. The relationships between CXCR4 SNPs and PGS and PegIFNα treatment response were explored in the two cohorts. Among the 22 candidate SNPs of CXCR4, rs28367495 (T > C) was significantly linked to PegIFNα treatment response in both cohorts. In patients with more number of rs28367495 C allele, a higher rate of combined response (CR, defined as HBeAg seroconversion and HBV DNA level < 3.3 log10 IU/mL; P = 1.51 × 10-4), a lower mean hepatitis B surface antigen (HBsAg) level (P = 4.76 × 10-4), and a higher mean HBsAg decline (P = 3.88 × 10-4) at Week 72 were achieved. Moreover, a PGS integrating CXCR4_rs28367495 and five previously reported SNPs was strongly correlated with CR (P = 1.26 × 10-13), HBsAg level (P = 4.90 × 10-4), and HBsAg decline (P = 0.005) in all the patients of the two cohorts. CXCR4_rs28367495 is a promising indicator for predicting the responsiveness to PegIFNα treatment for HBeAg-positive CHB patients. The new PGS may further improve the prediction performance.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Antivirais/uso terapêutico , Antivirais/farmacologia , DNA Viral , Hepatite B/tratamento farmacológico , Antígenos E da Hepatite B , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Interferon-alfa/farmacologia , Polietilenoglicóis/uso terapêutico , Polietilenoglicóis/farmacologia , Receptores CXCR4/genética , Proteínas Recombinantes , Estudos Retrospectivos , Resultado do Tratamento
7.
Diabetol Metab Syndr ; 16(1): 12, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38191425

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) has been associated with lipid-lowering drugs in observational studies. Drug-target Mendelian randomization (MR) was utilized in this study to examine the causal relationship between lipid-lowering drugs and incidence of IBD, aiming to identify new preventive uses for the drugs. METHODS: We identified instrumental variables for three classes of lipid-lowering drugs: HMGCR inhibitors, PCSK9 inhibitors, and NPC1L1 inhibitors, using data from the Global Lipids Genetics Consortium. Summary statistics of IBD were obtained from UK Inflammatory Bowel Disease Genetics. The summary-data-based MR (SMR) and the inverse-variance weighted (IVW) MR were used for analysis. Sensitivity analyses were performed by conventional MR methods. RESULTS: The SMR analysis showed no significant genetic association between increased gene expression of HMGCR, PCSK9, and NPC1L1 and IBD, Crohn's disease (CD) and ulcerative colitis (UC). According to IVW-MR analysis, increased HMGCR expression is associated with a reduced risk of IBD (OR = 0.73, 95% confidence interval (CI) 0.59-0.90, P = 0.003) and CD (OR = 0.75, 95% CI 0.57-0.97, P = 0.03), but not with UC. Additionally, increased NPC1L1 gene expression was associated with elevated risk of IBD (OR = 1.60, 95% CI 1.07-2.40, P = 0.023), but not with CD and UC. However, no significant causal relationships were found between PCSK9 gene expression and IBD, CD, and UC. The sensitivity analysis demonstrated no evidence of heterogeneity or pleiotropy among the reported results. CONCLUSIONS: The heightened expression of genetic variations in HMGCR inhibitor targets could potentially reduce the risk of IBD and CD, while genetic variation in the expression of NPC1L1 targets was positively associated with IBD.

8.
J Org Chem ; 89(3): 1967-1979, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38241611

RESUMO

Herein, we describe an effective method for the synthesis of 2-alkoxyamides and 1,2-diamines through visible-light-mediated difunctionalization of alkenes. N-Aminopyridinium salts were employed as appropriate precursors to generate key amidyl radical intermediates via a photoinduced single-electron transfer (SET) process. The amidyl radicals would react with alkenes, followed by oxidation and nucleophilic addition. Excellent functional group tolerance and good yields demonstrate the synthetic potential of this transformation.

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