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1.
Am J Physiol Cell Physiol ; 327(2): C329-C340, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38881420

RESUMEN

Family with sequence similarity 135 member B (FAM135B) is a novel driver gene in esophageal squamous cell carcinoma (ESCC). However, little is known regarding its biological functions and mechanisms in ESCC. Here, we identified that the high expression of FAM135B was associated with lymph node metastasis and infiltrating development of ESCC. Elevated FAM135B expression promoted ESCC migration and invasion in vitro and lung metastasis in vivo. Furthermore, epithelial-mesenchymal transition (EMT)-related pathways were enriched in ESCC samples with high levels of FAM135B and FAM135B positively regulated EMT markers. Mechanistically, we observed that FAM135B interacted with the intermediate domain of TRAF2 and NCK-interacting kinase (TNIK), activating the Wnt/ß-catenin signaling pathway. The facilitation of TNIK on ESCC migration and invasion was reversed by FAM135B siRNA. In addition, the N6-methyladenosine (m6A) modification positively regulated FAM135B expression, with methyltransferase like 3 (METTL3) acting as its substantial m6A writer. The pro-EMT effects of METTL3 overexpression were reversed by silencing FAM135B. Collectively, these findings illustrate the critical role of ABCDE in ESCC progression and provide new insights into the upstream and downstream mechanisms of FAM135B.NEW & NOTEWORTHY This study reveals for the first time that the novel cancer-related gene, FAM135B, promotes ESCC metastasis both in vitro and in vivo. Besides, we substantiate FAM135B's action on the ß-catenin pathway through interacting with TNIK, thereby elucidating the promotional effect of FAM135B on ESCC EMT. Furthermore, we provide initial evidence demonstrating that METTL3-mediated m6A modification upregulates the expression of FAM135B in ESCC cells.


Asunto(s)
Movimiento Celular , Transición Epitelial-Mesenquimal , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Regulación Neoplásica de la Expresión Génica , Metiltransferasas , Regulación hacia Arriba , Vía de Señalización Wnt , Humanos , Vía de Señalización Wnt/genética , Transición Epitelial-Mesenquimal/genética , Metiltransferasas/genética , Metiltransferasas/metabolismo , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/metabolismo , Línea Celular Tumoral , Animales , Masculino , Femenino , Ratones Desnudos , Ratones , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , beta Catenina/metabolismo , beta Catenina/genética , Invasividad Neoplásica , Ratones Endogámicos BALB C , Metástasis Linfática , Persona de Mediana Edad , Adenosina/análogos & derivados , Adenosina/metabolismo , Adenosina/genética
2.
Chem Biol Interact ; 395: 111013, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38663798

RESUMEN

Ulcerative colitis is a chronic disease with colonic mucosa injury. Nitazoxanide is an antiprotozoal drug in clinic. Nitazoxanide and its metabolite tizoxanide have been demonstrated to activate AMPK and inhibit inflammation, therefore, the aim of the present study is to investigate the effect of nitazoxanide on dextran sulfate sodium (DSS)-induced colitis and the underlying mechanism. Oral administration of nitazoxanide ameliorated the symptoms of mice with DSS-induced colitis, as evidenced by improving the increased disease activity index (DAI), the decreased body weight, and the shortened colon length. Oral administration of nitazoxanide ameliorated DSS-induced intestinal barrier dysfunction and reduced IL-6 and IL-17 expression in colon tissues. Mechanistically, nitazoxanide and its metabolite tizoxanide treatment activated AMPK and inhibited JAK2/STAT3 signals. Nitazoxanide and tizoxanide treatment increased caudal type homeobox 2 (CDX2) expression, increased alkaline phosphatase (ALP) activity and promoted tight junctions in Caco-2 cells. Nitazoxanide and tizoxanide treatment restored the decreased zonula occludens-1(ZO-1) and occludin protein levels induced by LPS or IL-6 in Caco-2 cells. On the other hand, nitazoxanide and tizoxanide regulated macrophage bias toward M2 polarization, as evidenced by the increased arginase-1expression in bone marrow-derived macrophages (BMDM). Nitazoxanide and tizoxanide reduced the increased IL-6, iNOS and CCL2 pro-inflammatory gene expressions and inhibited JAK2/STAT3 activation in BMDM induced by LPS. In conclusion, nitazoxanide protects against DSS-induced ulcerative colitis in mice through improving intestinal barrier and inhibiting inflammation and the underlying mechanism involves AMPK activation and JAK2/STAT3 inhibition.


Asunto(s)
Colitis Ulcerosa , Sulfato de Dextran , Mucosa Intestinal , Nitrocompuestos , Factor de Transcripción STAT3 , Tiazoles , Animales , Tiazoles/farmacología , Tiazoles/uso terapéutico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/patología , Colitis Ulcerosa/metabolismo , Nitrocompuestos/farmacología , Ratones , Humanos , Células CACO-2 , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Sulfato de Dextran/toxicidad , Factor de Transcripción STAT3/metabolismo , Masculino , Janus Quinasa 2/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Inflamación/tratamiento farmacológico , Colon/efectos de los fármacos , Colon/patología , Colon/metabolismo , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo II/metabolismo , Interleucina-6/metabolismo , Modelos Animales de Enfermedad
3.
Biochem Pharmacol ; 224: 116205, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38615918

RESUMEN

Nitazoxanide is an FDA-approved antiprotozoal drug. Our previous studies find that nitazoxanide and its metabolite tizoxanide affect AMPK, STAT3, and Smad2/3 signals which are involved in the pathogenesis of liver fibrosis, therefore, in the present study, we examined the effect of nitazoxanide on experimental liver fibrosis and elucidated the potential mechanisms. The in vivo experiment results showed that oral nitazoxanide (75, 100 mg·kg-1) significantly improved CCl4- and bile duct ligation-induced liver fibrosis in mice. Oral nitazoxanide activated the inhibited AMPK and inhibited the activated STAT3 in liver tissues from liver fibrosis mice. The in vitro experiment results showed that nitazoxanide and its metabolite tizoxanide activated AMPK and inhibited STAT3 signals in LX-2 cells (human hepatic stellate cells). Nitazoxanide and tizoxanide inhibited cell proliferation and collagen I expression and secretion of LX-2 cells. Nitazoxanide and tizoxanide inhibited transforming growth factor-ß1 (TGF-ß1)- and IL-6-induced increases of cell proliferation, collagen I expression and secretion, inhibited TGF-ß1- and IL-6-induced STAT3 and Smad2/3 activation in LX-2 cells. In mouse primary hepatic stellate cells, nitazoxanide and tizoxanide also activated AMPK, inhibited STAT3 and Smad2/3 activation, inhibited cell proliferation, collagen I expression and secretion. In conclusion, nitazoxanide inhibits liver fibrosis and the underlying mechanisms involve AMPK activation, and STAT3 and Smad2/3 inhibition.


Asunto(s)
Antiprotozoarios , Nitrocompuestos , Tiazoles , Animales , Ratones , Tiazoles/farmacología , Tiazoles/uso terapéutico , Masculino , Humanos , Antiprotozoarios/farmacología , Antiprotozoarios/uso terapéutico , Línea Celular , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Cirrosis Hepática/inducido químicamente , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/antagonistas & inhibidores , Proteína smad3/metabolismo , Cirrosis Hepática Experimental/inducido químicamente , Cirrosis Hepática Experimental/patología , Cirrosis Hepática Experimental/tratamiento farmacológico , Cirrosis Hepática Experimental/metabolismo , Cirrosis Hepática Experimental/prevención & control , Ratones Endogámicos C57BL , Proteína Smad2/metabolismo
4.
Hepatobiliary Surg Nutr ; 13(2): 198-213, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38617471

RESUMEN

Background: Adequate evaluation of degrees of liver cirrhosis is essential in surgical treatment of hepatocellular carcinoma (HCC) patients. The impact of the degrees of cirrhosis on prediction of post-hepatectomy liver failure (PHLF) remains poorly defined. This study aimed to construct and validate a combined pre- and intra-operative nomogram based on the degrees of cirrhosis in predicting PHLF in HCC patients using prospective multi-center's data. Methods: Consecutive HCC patients who underwent hepatectomy between May 18, 2019 and Dec 19, 2020 were enrolled at five tertiary hospitals. Preoperative cirrhotic severity scoring (CSS) and intra-operative direct liver stiffness measurement (DSM) were performed to correlate with the Laennec histopathological grading system. The performances of the pre-operative nomogram and combined pre- and intra-operative nomogram in predicting PHLF were compared with conventional predictive models of PHLF. Results: For 327 patients in this study, histopathological studies showed the rates of HCC patients with no, mild, moderate, and severe cirrhosis were 41.9%, 29.1%, 22.9%, and 6.1%, respectively. Either CSS or DSM was closely correlated with histopathological stages of cirrhosis. Thirty-three (10.1%) patients developed PHLF. The 30- and 90-day mortality rates were 0.9%. Multivariate regression analysis showed four pre-operative variables [HBV-DNA level, ICG-R15, prothrombin time (PT), and CSS], and one intra-operative variable (DSM) to be independent risk factors of PHLF. The pre-operative nomogram was constructed based on these four pre-operative variables together with total bilirubin. The combined pre- and intra-operative nomogram was constructed by adding the intra-operative DSM. The pre-operative nomogram was better than the conventional models in predicting PHLF. The prediction was further improved with the combined pre- and intra-operative nomogram. Conclusions: The combined pre- and intra-operative nomogram further improved prediction of PHLF when compared with the pre-operative nomogram. Trial Registration: Clinicaltrials.gov Identifier: NCT04076631.

5.
Free Radic Biol Med ; 214: 101-113, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38360276

RESUMEN

Sorafenib is a targeted anticancer drug in clinic. Low-dose sorafenib has been reported to activate AMPK through inducing mitochondrial uncoupling without detectable toxicities. AMPK activation has been the approach for extending lifespan, therefore, we investigated the effect of sorafenib on lifespan and physical activity of C. elegans and the underlying mechanisms. In the present study, we found that the effect of sorafenib on C. elegans lifespan was typically hermetic. Sorafenib treatment at higher concentrations (100 µM) was toxic but at lower concentrations (1, 2.5, 5 µM) was beneficial to C. elegans. Sorafenib (1 µM) treatment for whole-life period extended C. elegans lifespan and improved C. elegans physical activity as manifested by increasing pharyngeal pumping and body movement, preserving intestinal barrier integrity, muscle fibers organization and mitochondrial morphology. In addition, sorafenib (1 µM) treatment enhanced C. elegans stress resistance. Sorafenib activated AMPK through inducing mitochondrial uncoupling in C. elegans. Sorafenib treatment activated DAF-16, SKN-1, and increased SOD-3, HSP-16.2, GST-4 expression in C. elegans. Sorafenib treatment induced AMPK-dependent autophagy in C. elegans. We conclude that low-dose sorafenib protects C. elegans against aging through activating AMPK/DAF-16 dependent anti-oxidant pathways and stimulating autophagy responses. Low-dose sorafenib could be a strategy for treating aging and aging-related diseases.


Asunto(s)
Caenorhabditis elegans , Longevidad , Animales , Caenorhabditis elegans/genética , Sorafenib/farmacología , Proteínas Quinasas Activadas por AMP/genética , Envejecimiento
6.
Basic Clin Pharmacol Toxicol ; 134(4): 498-506, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38379124

RESUMEN

Psoriasis is a chronic inflammatory skin disease. Topical medicines are the preferred treatment for mild to moderate psoriasis, but the effect of excipients used in semi-solid preparations on psoriasis-like skin inflammation is not fully understood. In the present study, we investigated the effect of stearyl alcohol, a commonly used excipient, on imiquimod (IMQ)-induced psoriasis-like skin inflammation in mice. Psoriasis-like skin inflammation was induced by topical IMQ treatment on the back of mice. Skin lesion severity was evaluated by using psoriasis area and severity index (PASI) scores. The skin sections were stained by haematoxylin-eosin and immunohistochemistry. Stearyl alcohol (20% in vaseline) treatment significantly reduced the IMQ-induced increase of PASI scores and epidermal thickness in mice. IMQ treatment increased the number of Ki67- and proliferating cell nuclear antigen (PCNA)-positive cells in the skin, and the increases were inhibited by stearyl alcohol (20% in vaseline) treatment. Stearyl alcohol treatment (1%, 5%, 10% in vaseline) dose-dependently ameliorated IMQ-induced increase of PASI scores and epidermal thickness in mice. Hexadecanol (20% in vaseline), stearic acid (20% in vaseline) and vaseline treatment had no significant effect on IMQ-induced psoriasis-like skin inflammation in mice. In conclusion, stearyl alcohol has the effect of improving IMQ-induced psoriasis-like skin inflammation in mice.


Asunto(s)
Dermatitis , Alcoholes Grasos , Psoriasis , Ratones , Animales , Imiquimod/efectos adversos , Psoriasis/inducido químicamente , Psoriasis/tratamiento farmacológico , Dermatitis/patología , Piel , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/patología , Vaselina/efectos adversos , Modelos Animales de Enfermedad , Ratones Endogámicos BALB C
7.
Sheng Li Xue Bao ; 75(4): 575-586, 2023 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-37583045

RESUMEN

Obstructive sleep apnea syndrome (OSAS), a prevalent sleep disorder in children, is characterized by recurring upper airway obstruction during sleep. OSAS in children can cause intermittent hypoxia and sleep fragmentation, ultimately affect brain development and further lead to cognitive impairment if lack of timely effective intervention. In recent years, magnetic resonance imaging (MRI) and electroencephalogram (EEG) have been employed to investigate brain structure and function abnormalities in children with OSAS. Previous studies have indicated that children with OSAS showed extensive gray and white matter damage, abnormal brain function in regions such as the frontal lobe and hippocampus, as well as a significant decline in general cognitive function and executive function. However, the existing studies mainly focused on the regional activity, and the mechanism of pediatric OSAS affecting brain networks remains unknown. Moreover, it's unclear whether the alterations in brain structure and function are associated with their cognitive impairment. In this review article, we proposed two future research directions: 1) future studies should utilize the multimodal neuroimaging techniques to reveal the alterations of brain networks organization underlying pediatric OSAS; 2) further investigation is necessary to explore the relationship between brain network alteration and cognitive dysfunction in children with OSAS. With these efforts, it will be promising to identify the neuroimaging biomarkers for monitoring the brain development of children with OSAS as well as aiding its clinical diagnosis, and ultimately develop more effective strategies for intervention, diagnosis, and treatment.


Asunto(s)
Apnea Obstructiva del Sueño , Humanos , Niño , Apnea Obstructiva del Sueño/complicaciones , Cognición , Hipoxia/complicaciones , Hipocampo , Lóbulo Frontal
8.
Br J Pharmacol ; 180(23): 3008-3023, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37428102

RESUMEN

BACKGROUND AND PURPOSE: Nitazoxanide is a therapeutic anthelmintic drug. Our previous studies found that nitazoxanide and its metabolite tizoxanide activated adenosine 5'-monophosphate-activated protein kinase (AMPK) and inhibited signal transducer and activator of transcription 3 (STAT3) signals. As AMPK activation and/or STAT3 inhibition are targets for treating pulmonary fibrosis, we hypothesized that nitazoxanide would be effective in experimental pulmonary fibrosis. EXPERIMENTAL APPROACH: The mitochondrial oxygen consumption rate of cells was measured by using the high-resolution respirometry system Oxygraph-2K. The mitochondrial membrane potential of cells was evaluated by tetramethyl rhodamine methyl ester (TMRM) staining. The target protein levels were measured by using western blotting. The mice pulmonary fibrosis model was established through intratracheal instillation of bleomycin. The examination of the lung tissues changes were carried out using haematoxylin and eosin (H&E), and Masson staining. KEY RESULTS: Nitazoxanide and tizoxanide activated AMPK and inhibited STAT3 signalling in human lung fibroblast cells (MRC-5 cells). Nitazoxanide and tizoxanide inhibited transforming growth factor-ß1 (TGF-ß1)-induced proliferation and migration of MRC-5 cells, collagen-I and α-smooth muscle cell actin (α-SMA) expression, and collagen-I secretion from MRC-5 cells. Nitazoxanide and tizoxanide inhibited epithelial-mesenchymal transition (EMT) and inhibited TGF-ß1-induced Smad2/3 activation in mouse lung epithelial cells (MLE-12 cells). Oral administration of nitazoxanide reduced the bleomycin-induced mice pulmonary fibrosis and, in the established bleomycin-induced mice, pulmonary fibrosis. Delayed nitazoxanide treatment attenuated the fibrosis progression. CONCLUSIONS AND IMPLICATIONS: Nitazoxanide improves the bleomycin-induced pulmonary fibrosis in mice, suggesting a potential application of nitazoxanide for pulmonary fibrosis treatment in the clinic.


Asunto(s)
Antihelmínticos , Nitrocompuestos , Fibrosis Pulmonar , Tiazoles , Humanos , Ratones , Animales , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Proteínas Quinasas Activadas por AMP , Bleomicina , Colágeno Tipo I , Modelos Animales de Enfermedad , Antihelmínticos/efectos adversos , Ratones Endogámicos C57BL
9.
Br J Pharmacol ; 180(14): 1862-1877, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36740831

RESUMEN

BACKGROUND AND PURPOSE: Piezo1 channels are mechanosensitive cationic channels that are activated by mechanical stretch or shear stress. Endothelial Piezo1 activation by shear stress caused by blood flow induces ATP release from endothelial cells; however, the link between shear stress and endothelial ATP production is unclear. EXPERIMENTAL APPROACH: The mitochondrial respiratory function of cells was measured by using high-resolution respirometry system Oxygraph-2k. The intracellular Ca2+ concentration was evaluated by using Fluo-4/AM and mitochondrial Ca2+ concentration by Rhod-2/AM. KEY RESULTS: The specific Piezo1 channel activator Yoda1 or its analogue Dooku1 increased [Ca2+ ]i in human umbilical vein endothelial cells (HUVECs), and both Yoda1 and Dooku1 increased mitochondrial oxygen consumption rates (OCRs) and mitochondrial ATP production in HUVECs and primary cultured rat aortic endothelial cells (RAECs). Knockdown of Piezo1 inhibited Yoda1- and Dooku1-induced increases of mitochondrial OCRs and mitochondrial ATP production in HUVECs. The shear stress mimetics, Yoda1 and Dooku1, and the Piezo1 knock-down technique also demonstrated that Piezo1 activation increased glycolysis in HUVECs. Chelating extracellular Ca2+ with EGTA or chelating cytosolic Ca2+ with BAPTA-AM did not affect Yoda1- and Dooku1-induced increases of mitochondrial OCRs and ATP production, but chelating cytosolic Ca2+ inhibited Yoda1- and Dooku1-induced increase of glycolysis. Confocal microscopy showed that Piezo1 channels are present in mitochondria of endothelial cells, and Yoda1 and Dooku1 increased mitochondrial Ca2+ in endothelial cells. CONCLUSION AND IMPLICATIONS: Piezo1 channel activation stimulates ATP production through enhancing mitochondrial respiration and glycolysis in vascular endothelial cells, suggesting a novel role of Piezo1 channel in endothelial ATP production.


Asunto(s)
Canales Iónicos , Mitocondrias , Animales , Humanos , Ratas , Adenosina Trifosfato , Glucólisis , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Canales Iónicos/metabolismo , Mitocondrias/metabolismo , Respiración
10.
Br J Pharmacol ; 180(1): 62-79, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36082580

RESUMEN

BACKGROUND AND PURPOSE: The anthelmintic drug nitazoxanide has a mitochondrial uncoupling effect. Mitochondrial uncouplers have been proven to inhibit smooth muscle cell proliferation and migration, inhibit NLRP3 inflammasome activation of macrophages and improve dyslipidaemia. Therefore, we aimed to demonstrate that nitazoxanide would protect against atherosclerosis. EXPERIMENTAL APPROACH: The mitochondrial oxygen consumption of cells was measured by using the high-resolution respirometry system, Oxygraph-2K. The proliferation and migration of A10 cells were measured by using Edu immunofluorescence staining, wound-induced migration and the Boyden chamber assay. Protein levels were measured by using the western blot technique. ApoE (-/-) mice were fed with a Western diet to establish an atherosclerotic model in vivo. KEY RESULTS: The in vitro experiments showed that nitazoxanide and tizoxanide had a mitochondrial uncoupling effect and activated cellular AMPK. Nitazoxanide and tizoxanide inhibited serum- and PDGF-induced proliferation and migration of A10 cells. Nitazoxanide and tizoxanide inhibited NLRP3 inflammasome activation in RAW264.7 macrophages, the mechanism by which involved the AMPK/IκBα/NF-κB pathway. Nitazoxanide and tizoxanide also induced autophagy in A10 cells and RAW264.7 macrophages. The in vivo experiments demonstrated that oral administration of nitazoxanide reduced the increase in serum IL-1ß and IL-6 levels and suppressed atherosclerosis in Western diet-fed ApoE (-/-) mice. CONCLUSION AND IMPLICATIONS: Nitazoxanide inhibits the formation of atherosclerotic plaques in ApoE (-/-) mice fed on a Western diet. In view of nitazoxanide being an antiprotozoal drug already approved by the FDA, we propose it as a novel anti-atherosclerotic drug with clinical translational potential.


Asunto(s)
Aterosclerosis , Ratones , Animales , Preparaciones Farmacéuticas/metabolismo , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/metabolismo , Mitocondrias/metabolismo , Nitrocompuestos/farmacología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Inflamasomas/metabolismo
11.
Science ; 377(6608): 880-885, 2022 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-35981028

RESUMEN

The B cell receptor (BCR) complex plays a critical role in B cell development and immune responses. The assembly mechanisms underlying the BCR complex remain unknown. We determined the cryo-electron microscopy (cryo-EM) structures of human IgG-BCR and IgM-BCR, which consist of membrane-bound immunoglobulin molecules (mIg) and Igα/ß subunits at a 1:1 stoichiometry. Assembly of both BCR complexes involves their extracellular domains, membrane-proximal connection peptides, and transmembrane (TM) helices. The TM helices of mIgG and mIgM share a conserved set of hydrophobic and polar interactions with Igα/ß TM helices. By contrast, the IgG-Cγ3 and IgM-Cµ4 domains interact with extracellular Ig-like domains of Igα/ß through head-to-tail and side-by-side modes, respectively. This work reveals the structural basis for BCR assembly and provides insights into BCR triggering.


Asunto(s)
Antígenos CD79 , Inmunoglobulina G , Inmunoglobulina M , Antígenos CD79/química , Microscopía por Crioelectrón , Humanos , Inmunoglobulina G/química , Inmunoglobulina M/química , Conformación Proteica en Hélice alfa
12.
Adv Sci (Weinh) ; 9(14): e2104333, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35403837

RESUMEN

Coronavirus disease 2019 (COVID-19) remains a global public health threat. Hence, more effective and specific antivirals are urgently needed. Here, COVID-19 hyperimmune globulin (COVID-HIG), a passive immunotherapy, is prepared from the plasma of healthy donors vaccinated with BBIBP-CorV (Sinopharm COVID-19 vaccine). COVID-HIG shows high-affinity binding to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein, the receptor-binding domain (RBD), the N-terminal domain of the S protein, and the nucleocapsid protein; and blocks RBD binding to human angiotensin-converting enzyme 2 (hACE2). Pseudotyped and authentic virus-based assays show that COVID-HIG displays broad-spectrum neutralization effects on a wide variety of SARS-CoV-2 variants, including D614G, Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Kappa (B.1.617.1), Delta (B.1.617.2), and Omicron (B.1.1.529) in vitro. However, a significant reduction in the neutralization titer is detected against Beta, Delta, and Omicron variants. Additionally, assessments of the prophylactic and treatment efficacy of COVID-HIG in an Adv5-hACE2-transduced IFNAR-/- mouse model of SARS-CoV-2 infection show significantly reduced weight loss, lung viral loads, and lung pathological injury. Moreover, COVID-HIG exhibits neutralization potency similar to that of anti-SARS-CoV-2 hyperimmune globulin from pooled convalescent plasma. Overall, the results demonstrate the potential of COVID-HIG against SARS-CoV-2 infection and provide reference for subsequent clinical trials.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Globulinas , Animales , COVID-19/terapia , Globulinas/uso terapéutico , Humanos , Inmunización Pasiva , Ratones , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Sueroterapia para COVID-19
13.
Mol Cell ; 82(7): 1278-1287.e5, 2022 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-35271814

RESUMEN

Cholesterol molecules specifically bind to the resting αßTCR to inhibit cytoplasmic CD3ζ ITAM phosphorylation through sequestering the TCR-CD3 complex in an inactive conformation. The mechanisms of cholesterol-mediated inhibition of TCR-CD3 and its activation remain unclear. Here, we present cryoelectron microscopy structures of cholesterol- and cholesterol sulfate (CS)-inhibited TCR-CD3 complexes and an auto-active TCR-CD3 variant. The structures reveal that cholesterol molecules act like a latch to lock CD3ζ into an inactive conformation in the membrane. Mutations impairing binding of cholesterol molecules to the tunnel result in the movement of the proximal C terminus of the CD3ζ transmembrane helix, thereby activating the TCR-CD3 complex in human cells. Together, our data reveal the structural basis of TCR inhibition by cholesterol, illustrate how the cholesterol-binding tunnel is allosterically coupled to TCR triggering, and lay a foundation for the development of immunotherapies through directly targeting the TCR-CD3 complex.


Asunto(s)
Complejo Receptor-CD3 del Antígeno de Linfocito T , Linfocitos T , Complejo CD3/genética , Complejo CD3/metabolismo , Colesterol/metabolismo , Microscopía por Crioelectrón , Humanos , Complejo Receptor-CD3 del Antígeno de Linfocito T/genética , Complejo Receptor-CD3 del Antígeno de Linfocito T/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/metabolismo
14.
Front Surg ; 9: 762212, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35310439

RESUMEN

Purpose: Aggressive angiomyxoma (AAM) was identified as a distinct clinicopathological entity in 1983. Since then, a few cases of its occurrence in the scrotum have been reported. This case series was performed to increase clinicians' understanding of the clinical features and treatment of AAM in the scrotum. Methods: We evaluated the clinical presentations, treatments, and follow-up of two patients with AAM in the scrotum in our hospital and 34 cases reported in the literature. Results: Among the 36 patients, the average age was 48.3 ± 20.6 years old (range from 1 to 81); the average maximum diameter of the tumor was 8.36 cm (1.6-25 cm); the site of one (2.78%) patient was located in the epididymis, two (5.56%) in the testes, five (13.89%) in the spermatic cord, and 28 (77.77%) in the scrotum. The clinical symptoms were generally non-specific and 20 patients inadvertently discovered their slow-growing painless masses. The treatments for all these patients were surgical excision once the tumor had been found and one case underwent excision followed by radiotherapy. The median follow-up time for the remaining 32 cases was 24.5 months (1 to 84 months). Recurrence occurred in three cases (9.09%) at the primary sites and no cases of distant metastasis. Conclusion: AAM of the scrotum can occur in middle-aged and elderly men. The clinical manifestation generally involves a long history of asymptomatic masses or swelling in the scrotum. Ultrasound is the most commonly used diagnostic technique but magnetic resonance imaging may be more effective. The mainly treatment is surgical excision and postoperative histopathological examination is still the gold standard for its diagnosis. Although it is locally aggressive, metastasis is extremely rare in males.

15.
Mater Horiz ; 9(3): 1036-1044, 2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35022629

RESUMEN

Phase engineering of two-dimensional transition metal dichalcogenides has received increasing attention in recent years due to its atomically thin nature and polymorphism. Here, we first realize an electric-field-induced controllable phase transition between semiconducting 2H and metallic 1T' phases in MoTe2 memristive devices. The device performs stable bipolar resistive switching with a cycling endurance of over 105, an excellent retention characteristic of over 105 s at an elevated temperature of 85 °C and an ultrafast switching of ∼5 ns for SET and ∼10 ns for RESET. More importantly, the device works in different atmospheres including air, vacuum and oxygen, and even works with no degradation after being placed in air for one year, indicating excellent surrounding and time stability. In situ Raman analysis reveals that the stable resistive switching originates from a controllable phase transition between 2H and 1T' phases. Density functional theory calculations reveal that the Te vacancy facilitates the phase transition in MoTe2 through decreasing the barrier between 2H and 1T' phases, and serving as nucleation sites due to the elimination of repulsive forces. This electric-field-induced controllable phase transition in MoTe2 devices offers new opportunities for developing reliable and ultrafast phase transition devices based on atomically thin membranes.

16.
Zhonghua Nan Ke Xue ; 27(6): 483-488, 2021 Jun.
Artículo en Chino | MEDLINE | ID: mdl-34914286

RESUMEN

OBJECTIVE: To explore the possible pathogenesis of chronic nonbacterial prostatitis (CNP) in rats from the perspective of mitochondria, and the interventional effect of Jiedu Huoxue Decoction (JHD) on CNP. METHODS: Forty clean-grade SD male rats were randomly divided into 4 groups of an equal number, sham control, CNP model control, Qianliekang Tablets intervention (QLK) and JHD intervention, those in the former two groups treated intragastrically with normal saline, and those in the latter two with QLK and JHD, respectively, at 2g/kg qd for 30 successive days. Then serum and prostate tissue samples were collected from the rats for calculation of the organ coefficients, HE staining, extraction of mitochondria in the prostate tissue, measurement of the levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-PX) and Na+-K+-ATPase by colorimetric assay, and observation of the ultrastructural changes of the prostatic epithelial cells under the transmission electron microscope (TEM). RESULTS: The organ coefficient of the prostate was significantly higher in the CNP model controls (ï¼»1.95 ± 0.39ï¼½%) than in the sham control (ï¼»1.50 ± 0.42ï¼½%, P < 0.05), QLK (ï¼»1.54 ± 0.32ï¼½%, P < 0.05) and JHD groups (ï¼»1.47 ± 0.53ï¼½%, P < 0.05). TEM showed significant hyperplasia of the interstitial fibrous tissue, glandular structural disorder and inflammatory cell immersion in the CNP model controls, decreased inflammatory cells and reduced hyperplasia of epithelial cells in the acinar and interstitial fibrous tissues in the QLK and JHD groups, but no significant changes in the sham controls. The CNP model controls, compared with the QLK and JHD groups, exhibited remarkably lower levels of SOD (ï¼»17.42 ± 2.91ï¼½ vs ï¼»23.47 ± 5.79ï¼½ and ï¼»22.52 ± 3.88ï¼½ U/mg prot, P < 0.05), GSH-PX (ï¼»38.35 ± 6.98ï¼½ vs ï¼»47.68 ± 10.37ï¼½ and ï¼»89.95 ± 7.65ï¼½ U/mg prot, P < 0.05 or P < 0.01), and Na+-K+-ATPase in the prostatic mitochondria (ï¼»0.98 ± 0.40ï¼½ vs ï¼»1.37 ± 0.29ï¼½ and ï¼»1.85 ± 0.32ï¼½ µmol Pi/mg prot/h, P < 0.05 or P < 0.01), but a higher level of MDA (ï¼»1.70 ± 0.22ï¼½ vs ï¼»0.54 ± 0.14ï¼½ and ï¼»0.59 ± 0.17ï¼½ nmol/mg prot, P < 0.01). Significant mitochondrial damage was observed in the prostate tissue of the CNP model controls, and markedly enhanced mitochondrial autophagy was seen in the JHD group. CONCLUSIONS: Chronic nonbacterial prostatitis induces mitochondrial dysfunction in the prostate of rats, and Jiedu Huoxue Decoction can promote the recovery of mitochondrial function, which may be related to mitochondrial autophagy.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Mitocondrias/efectos de los fármacos , Prostatitis , Animales , Autofagia , Masculino , Mitocondrias/patología , Próstata/ultraestructura , Prostatitis/tratamiento farmacológico , Ratas
17.
Eur J Pharmacol ; 912: 174614, 2021 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-34736968

RESUMEN

The heart is a high energy demand organ and enhancing mitochondrial function is proposed as the next-generation therapeutics for heart failure. Our previous study found that anthelmintic drug niclosamide enhanced mitochondrial respiration and increased adenosine triphosphate (ATP) production in cardiomyocytes, therefore, this study aimed to determine the effect of niclosamide on heart failure in mice and the potential molecular mechanisms. The heart failure model was induced by transverse aortic constriction (TAC) in mice. Oral administration of niclosamide improved TAC-induced cardiac hypertrophy, cardiac fibrosis, and cardiac dysfunction in mice. Oral administration of niclosamide reduced TAC-induced increase of serum IL-6 in heart failure mice. In vitro, niclosamide within 0.1 µM increased mitochondrial respiration and ATP production in mice heart tissues. At the concentrations more than 0.1 µM, niclosamide reduced the increased interleukin- 6 (IL-6) mRNA expression in lipopolysaccharide (LPS)-stimulated RAW264.7 and THP-1 derived macrophages. In cultured primary cardiomyocytes and cardiac fibroblasts, niclosamide (more than 0.1 µM) suppressed IL-6- and phenylephrine-induced cardiomyocyte hypertrophy, and inhibited collagen secretion from cardiac fibroblasts. In conclusion, niclosamide attenuates heart failure in mice and the underlying mechanisms include enhancing mitochondrial respiration of cardiomyocytes, inhibiting collagen secretion from cardiac fibroblasts, and reducing the elevated serum inflammatory mediator IL-6. The present study suggests that niclosamide might be therapeutic for heart failure.


Asunto(s)
Antihelmínticos/farmacología , Insuficiencia Cardíaca/tratamiento farmacológico , Niclosamida/farmacología , Adenosina Trifosfato/metabolismo , Animales , Antihelmínticos/uso terapéutico , Cardiomegalia/inducido químicamente , Cardiomegalia/tratamiento farmacológico , Cardiomegalia/patología , Línea Celular , Colágeno/metabolismo , Modelos Animales de Enfermedad , Enalapril/farmacología , Enalapril/uso terapéutico , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/patología , Humanos , Interleucina-6/sangre , Interleucina-6/genética , Macrófagos/efectos de los fármacos , Masculino , Ratones , Mitocondrias/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Niclosamida/uso terapéutico , Fenilefrina/toxicidad , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Factor de Transcripción STAT3/metabolismo , Survivin/metabolismo
18.
Malar J ; 20(1): 374, 2021 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-34538247

RESUMEN

BACKGROUND: Plasmodium falciparum erythrocyte binding antigen-175 (PfEBA-175) is a candidate antigen for a blood-stage malaria vaccine, while various polymorphisms and dimorphism have prevented to development of effective vaccines based on this gene. This study aimed to investigate the dimorphism of PfEBA-175 on both the Bioko Island and continent of Equatorial Guinea, as well as the genetic polymorphism and natural selection of global PfEBA-175. METHODS: The allelic dimorphism of PfEBA-175 region II of 297 bloods samples from Equatorial Guinea in 2018 and 2019 were investigated by nested polymerase chain reaction and sequencing. Polymorphic characteristics and the effect of natural selection were analyzed using MEGA 7.0, DnaSP 6.0 and PopART programs. Protein function prediction of new amino acid mutation sites was performed using PolyPhen-2 and Foldx program. RESULTS: Both Bioko Island and Bata district populations, the frequency of the F-fragment was higher than that of the C-fragment of PfEBA-175 gene. The PfEBA-175 of Bioko Island and Bata district isolates showed a high degree of genetic variability and heterogeneity, with π values of 0.00407 & 0.00411 and Hd values of 0.958 & 0.976 for nucleotide diversity, respectively. The values of Tajima's D of PfEBA-175 on Bata district and Bioko Island were 0.56395 and - 0.27018, respectively. Globally, PfEBA-175 isolates from Asia were more diverse than those from Africa and South America, and genetic differentiation quantified by the fixation index between Asian and South American countries populations was significant (FST > 0.15, P < 0.05). A total of 310 global isolates clustered in 92 haplotypes, and only one cluster contained isolates from three continents. The mutations A34T, K109E, D278Y, K301N, L305V and D329N were predicted as probably damaging. CONCLUSIONS: This study demonstrated that the dimorphism of F-fragment PfEBA-175 was remarkably predominant in the study area. The distribution patterns and genetic diversity of PfEBA-175 in Equatorial Guinea isolates were similar another region isolates. And the levels of recombination events suggested that natural selection and intragenic recombination might be the main drivers of genetic diversity in global PfEBA-175. These results have important reference value for the development of blood-stage malaria vaccine based on this antigen.


Asunto(s)
Antígenos de Protozoos/genética , Plasmodium falciparum/genética , Polimorfismo Genético , Proteínas Protozoarias/genética , Selección Genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Guinea Ecuatorial , Humanos , Lactante , Malaria Falciparum/parasitología , Persona de Mediana Edad , Adulto Joven
19.
Malar J ; 20(1): 124, 2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33653360

RESUMEN

BACKGROUND: Thrombospondin-related adhesive protein (TRAP) is a transmembrane protein that plays a crucial role during the invasion of Plasmodium falciparum into liver cells. As a potential malaria vaccine candidate, the genetic diversity and natural selection of PfTRAP was assessed and the global PfTRAP polymorphism pattern was described. METHODS: 153 blood spot samples from Bioko malaria patients were collected during 2016-2018 and the target TRAP gene was amplified. Together with the sequences from database, nucleotide diversity and natural selection analysis, and the structural prediction were preformed using bioinformatical tools. RESULTS: A total of 119 Bioko PfTRAP sequences were amplified successfully. On Bioko Island, PfTRAP shows its high degree of genetic diversity and heterogeneity, with π value for 0.01046 and Hd for 0.99. The value of dN-dS (6.2231, p < 0.05) hinted at natural selection of PfTRAP on Bioko Island. Globally, the African PfTRAPs showed more diverse than the Asian ones, and significant genetic differentiation was discovered by the fixation index between African and Asian countries (Fst > 0.15, p < 0.05). 667 Asian isolates clustered in 136 haplotypes and 739 African isolates clustered in 528 haplotypes by network analysis. The mutations I116T, L221I, Y128F, G228V and P299S were predicted as probably damaging by PolyPhen online service, while mutations L49V, R285G, R285S, P299S and K421N would lead to a significant increase of free energy difference (ΔΔG > 1) indicated a destabilization of protein structure. CONCLUSIONS: Evidences in the present investigation supported that PfTRAP gene from Bioko Island and other malaria endemic countries is highly polymorphic (especially at T cell epitopes), which provided the genetic information background for developing an PfTRAP-based universal effective vaccine. Moreover, some mutations have been shown to be detrimental to the protein structure or function and deserve further study and continuous monitoring.


Asunto(s)
Malaria Falciparum/parasitología , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Epítopos , Guinea Ecuatorial/epidemiología , Frecuencia de los Genes , Variación Genética , Haplotipos , Humanos , Vacunas contra la Malaria , Malaria Falciparum/epidemiología , Malaria Falciparum/inmunología , Plasmodium falciparum/inmunología , Polimorfismo Genético , Proteínas Protozoarias/química , Proteínas Protozoarias/inmunología , Selección Genética
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