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1.
Polymers (Basel) ; 14(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35012224

RESUMO

Hydrogel composites can be prepared from cellulose-based materials and other gel materials, thus combining the advantages of both kinds of material. The aerogel, porous material formed after removing the water in the hydrogel, can maintain the network structure. Hydrogel and aerogel have high application potential. However, low mechanical strength and weight loss of cellulose hydrogel due to the water dehydration/absorption limit the feasibility of repeated use. In this study, cellulose hydrogels were prepared using microcrystalline cellulose (MC), carboxymethyl cellulose (CMC), and hydroxyethyl cellulose (HEC) as raw materials. Waterborne polyurethane (WPU) was added during the preparation process to form cellulose/WPU composite hydrogel and aerogel. The influence of the cellulose type and WPU addition ratio on the performance of hydrogel and aerogel were investigated. The results show that the introduction of WPU can help strengthen and stabilize the structure of cellulose hydrogel, reduce weight loss caused by water absorption and dehydration, and improve its reusability. The mixing of cellulose and WPU at a weight ratio of 90/10 is the best ratio to make the cellulose/WPU composite aerogel with the highest water swelling capacity and heat resistance.

2.
Immunity ; 54(8): 1728-1744.e7, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34343498

RESUMO

Inflammatory bowel disease (IBD) mainly includes Crohn's disease (CD) and ulcerative colitis (UC). Immune disorders play an essential role in the pathogenesis of these two IBDs, but the differences in the immune microenvironment of the colon and their underlying mechanisms remain poorly investigated. Here we examined the immunological features and metabolic microenvironment of untreated individuals with IBD by multiomics analyses. Modulation of CD-specific metabolites, particularly reduced selenium, can obviously shape type 1 T helper (Th1) cell differentiation, which is specifically enriched in CD. Selenium supplementation suppressed the symptoms and onset of CD and Th1 cell differentiation via selenoprotein W (SELW)-mediated cellular reactive oxygen species scavenging. SELW promoted purine salvage pathways and inhibited one-carbon metabolism by recruiting an E3 ubiquitin ligase, tripartite motif-containing protein 21, which controlled the stability of serine hydroxymethyltransferase 2. Our work highlights selenium as an essential regulator of T cell responses and potential therapeutic targets in CD.


Assuntos
Antioxidantes/farmacologia , Doença de Crohn/tratamento farmacológico , Doença de Crohn/imunologia , Selênio/farmacologia , Selenoproteína W/metabolismo , Células Th1/citologia , Diferenciação Celular/imunologia , Polaridade Celular , Colo/imunologia , Colo/patologia , Glicina Hidroximetiltransferase/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Ribonucleoproteínas/metabolismo , Células Th1/imunologia , Ubiquitina-Proteína Ligases/metabolismo
3.
Sci Adv ; 7(3)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33523871

RESUMO

The classic NF-κB pathway plays crucial roles in various immune responses and inflammatory diseases. Its key kinase, IKKß, participates in a variety of pathological and physiological processes by selectively recognizing its downstream substrates, including p105, p65, and IκBα, but the specific mechanisms of these substrates are unclear. Hyperactivation of one of the substrates, p105, is closely related to the onset of inflammatory bowel disease (IBD) in Nfkb1-deficient mice. In this study, we found that IKKß ubiquitination on lysine-238 was substantially increased during inflammation. Using mass spectrometry, we identified USP16 as an essential regulator of the IKKß ubiquitination level that selectively affected p105 phosphorylation without directly affecting p65 or IκBα phosphorylation. Furthermore, USP16 was highly expressed in colon macrophages in patients with IBD, and myeloid-conditional USP16-knockout mice exhibited reduced IBD severity. Our study provides a new theoretical basis for IBD pathogenesis and targeted precision intervention therapy.

4.
Gastroenterol Rep (Oxf) ; 7(5): 338-344, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31687153

RESUMO

BACKGROUND AND AIM: This cross-sectional study investigated the prevalence and risk factors of high-risk human papilloma virus (HPV) infection, especially types 16 and 18, and cervical neoplasia in female Inflammatory bowel disease (IBD) patients. METHODS: From July 2014 to January 2017, sexually active, female, Chinese IBD patients (21-60 years) and age-matched controls underwent cervical ThinPrep cytology testing (TCT) and high-risk HPV-DNA detection, and completed questionnaires about awareness of cervical cancer and HPV. Cervical dysplasia was categorized as cervical intraepithelial neoplasia (CIN) 1, 2 and 3. RESULTS: Of 124 IBD patients (30 ulcerative colitis and 94 Crohn's disease), 17 (13.7%) had high-risk HPV among whom 9 (7.3%) had HPV 16/18 infection and 4 (3.2%) had cervical CIN (3 CIN 3, 1 CIN 1) by pathology. Among 372 controls, 33 (8.9%) had high-risk HPV and only 1 (0.3%) had HPV 16 infection. Cervical TCT detected atypical squamous cells of unknown significance in one control; no control had CIN. The HPV 16/18 infection rate and CIN prevalence were significantly higher in IBD patients than controls (both P < 0.001). The HPV-infection rate was higher in patients administered methotrexate [P = 0.005, odds ratio (95% confidence interval) 4.76 (1.471-15.402)] or more than two immunosuppressants [P = 0.013, odds ratio (95% confidence interval) 3.64 (1.255-10.562)]. Thiopurine, steroid, infliximab and disease behavior/location were not associated with HPV infection. Only 29.3% of patients had undergone cervical-cancer screening. Awareness of HPV infection and HPV-related cervical cancer was poor (28.2%). CONCLUSIONS: Female IBD patients are at increased risk of high-risk HPV infection and cervical neoplasia, which may be associated with immunosuppressants. Education and routine follow-up with HPV-DNA testing and TCT are recommended, especially in female Chinese IBD patients.

5.
Cell ; 179(4): 864-879.e19, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31675497

RESUMO

Physical or mental stress leads to neuroplasticity in the brain and increases the risk of depression and anxiety. Stress exposure causes the dysfunction of peripheral T lymphocytes. However, the pathological role and underlying regulatory mechanism of peripheral T lymphocytes in mood disorders have not been well established. Here, we show that the lack of CD4+ T cells protects mice from stress-induced anxiety-like behavior. Physical stress-induced leukotriene B4 triggers severe mitochondrial fission in CD4+ T cells, which further leads to a variety of behavioral abnormalities including anxiety, depression, and social disorders. Metabolomic profiles and single-cell transcriptome reveal that CD4+ T cell-derived xanthine acts on oligodendrocytes in the left amygdala via adenosine receptor A1. Mitochondrial fission promotes the de novo synthesis of purine via interferon regulatory factor 1 accumulation in CD4+ T cells. Our study implicates a critical link between a purine metabolic disorder in CD4+ T cells and stress-driven anxiety-like behavior.


Assuntos
Ansiedade/metabolismo , Comportamento Animal/fisiologia , Encefalopatias Metabólicas/metabolismo , Estresse Psicológico/metabolismo , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/patologia , Animais , Ansiedade/genética , Ansiedade/imunologia , Ansiedade/fisiopatologia , Encefalopatias Metabólicas/genética , Encefalopatias Metabólicas/fisiopatologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Dinâmica Mitocondrial/genética , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Análise de Célula Única , Estresse Psicológico/genética , Estresse Psicológico/fisiopatologia , Transcriptoma/genética , Xantina/metabolismo
6.
J Clin Invest ; 129(7): 2856-2871, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31135381

RESUMO

Calcineurin acts as a calcium-activated phosphatase that dephosphorylates various substrates, including members of the nuclear factor of activated T cells (NFAT) family, to trigger their nuclear translocation and transcriptional activity. However, the detailed mechanism regulating the recruitment of NFATs to calcineurin remains poorly understood. Here, we report that calcineurin A (CNA), encoded by PPP3CB or PPP3CC, is constitutively ubiquitinated on lysine 327, and this polyubiquitin chain is rapidly removed by ubiquitin carboxyl-terminal hydrolase 16 (USP16) in response to intracellular calcium stimulation. The K29-linked ubiquitination of CNA impairs NFAT recruitment and transcription of NFAT-targeted genes. USP16 deficiency prevents calcium-triggered deubiquitination of CNA in a manner consistent with defective maintenance and proliferation of peripheral T cells. T cell-specific USP16 knockout mice exhibit reduced severity of experimental autoimmune encephalitis and inflammatory bowel disease. Our data reveal the physiological function of CNA ubiquitination and its deubiquitinase USP16 in peripheral T cells. Notably, our results highlight a critical mechanism for the regulation of calcineurin activity and a novel immunosuppressive drug target for the treatment of autoimmune diseases.


Assuntos
Doenças Autoimunes , Calcineurina , Linfócitos T , Ubiquitina Tiolesterase , Ubiquitinação , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Calcineurina/genética , Calcineurina/imunologia , Células HEK293 , Humanos , Camundongos , Camundongos Knockout , Linfócitos T/imunologia , Linfócitos T/patologia , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/imunologia , Ubiquitinação/genética , Ubiquitinação/imunologia
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