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1.
Polymers (Basel) ; 16(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38732661

RESUMO

A nano-structured conjugated polymer with multiple micro-/meso-pores was synthesized by post-crosslinking of an end-functionalized hyperbranched conjugated prepolymer. Firstly, an AB2 monomer 3-((3,5-dibromo-4-(octyloxy)phenyl)ethynyl)-6-ethynyl-9-octyl-9H-carbazole (PECz) was synthesized and polymerized by Sonogashira reaction to give the -Br end-functionalized hyperbranched conjugated prepolymer hb-PPECz. The photophysical and electrochemical properties of hb-PPECz were investigated. The λmax of absorption and emission of hb-PPECz in tetrahydrofuran (THF) solution was 313 and 483 nm, respectively. The optical energy bandgap, highest occupied molecular orbital (HOMO), and lowest unoccupied molecular orbital (LUMO) energy levels of hb-PPECz were 2.98, -5.81, and -2.83 eV, respectively. Then, the prepolymer hb-PPECz was post-crosslinked by Heck reaction with divinylbenzene to give the porous conjugated polymer c-PPECz. The effects of hb-PPECz concentration and added dispersant polyvinylpyrrolidone (PVP K-30) on the morphology and porosity of c-PPECz were investigated. The resulting c-PPECzs showed multiple porous structures mainly constructed by micropores and mesopores. Under a higher hb-PPECz concentration (4 wt/v%), a bulky gel product was obtained. Under lower hb-PPECz concentrations (0.6 wt/v%~2 wt/v%), the resulting c-PPECzs were mainly composed of nano-sized particles. Nearly spheric nanoparticles (200~300 nm) (c-PPECz-5) were obtained under the concentration of 1 wt/v% in the presence of PVP (10 wt% of hb-PPECz). The Brunauer-Emmett-Teller (BET) surface area, pore volume, average pore size, and percentage of pore size below 10 nm of c-PPECz-5 were 10.7781 m2·g-1, 0.0108 cm3·g-1, 4.0081 nm, and 94.47%, respectively.

2.
Eur J Pharm Biopharm ; 199: 114309, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704102

RESUMO

Oral colon targeted drug delivery system (OCTDDS) is desirable for the treatment of ulcerative colitis (UC). In this study, we designed a partially oxidized sodium alginate-chitosan crosslinked microsphere for UC treatment. Dissipative particle dynamics (DPD) was used to study the formation and enzyme response of gel beads from a molecular perspective. The formed gel beads have a narrow particle size distribution, a compact structure, low cytotoxicity and great colon targeting in vitro and in vivo. Animal experiments demonstrated that gel beads promoted colonic epithelial barrier integrity, decreased the level of pro-inflammatory factors, accelerated the recovery of intestinal microbial homeostasis in UC rats and restored the intestinal metabolic disorders. In conclusion, our gel bead is a promising approach for the treatment of UC and significant for the researches on the pathogenesis and treatment mechanism of UC.


Assuntos
Alginatos , Quitosana , Colite Ulcerativa , Sistemas de Liberação de Medicamentos , Géis , Microesferas , Saponinas , Colite Ulcerativa/tratamento farmacológico , Animais , Ratos , Alginatos/química , Quitosana/química , Sistemas de Liberação de Medicamentos/métodos , Masculino , Saponinas/farmacologia , Saponinas/administração & dosagem , Saponinas/química , Tamanho da Partícula , Humanos , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Ratos Sprague-Dawley , Polímeros/química , Modelos Animais de Doenças , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Administração Oral
3.
Diabetes Metab Syndr Obes ; 17: 1887-1901, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711676

RESUMO

Background: Diet and physical activity (PA) are pivotal behaviors for managing energy balance post-bariatric surgery. Given the need for dual behavioral management, understanding the interplay of cognitive factors influencing these behaviors is crucial. This study applied the compensatory carry-over action model (CCAM) to explore the impact of cognitive factors on behaviors and their subsequent effects on subjective health outcomes. Methods: This cross-sectional study was conducted among patients at the third month after bariatric surgery in China. Data on diet and PA status, behavioral cognitive factors (intention, self-efficacy, compensatory belief, transfer cognition), and subjective health outcomes (perceived stress, well-being, quality of life) were collected. Structural equation model (SEM) was employed to test hypotheses in CCAM and assess mediation relationships. Results: Analysis of data from 239 patients revealed the following: (1) Among antecedent cognitive factors, only compensatory belief significantly influenced diet (P<0.001). (2) Intention and self-efficacy directly correlated with their respective behaviors, while compensatory belief affected intention, and transfer cognition impacted self-efficacy (P<0.05), aligning with CCAM hypotheses. (3) PA demonstrated significant influence only on perceived stress (P=0.004), whereas diet significantly affected all subjective health outcomes (P<0.05). (4) Mediation analysis indicated intention partially mediated the relationship between compensatory belief and diet and fully mediated the relationship between compensatory belief and PA. Self-efficacy completely mediated the relationship between transfer cognition and diet and PA. Conclusion: Transfer cognition's carry-over effect did not directly influence behaviors among antecedent cognitions. Interventions should primarily target improving diet by mitigating compensatory belief. Moreover, diet exhibited a more pronounced impact on overall health compared to PA. Consequently, prioritizing dietary intervention over PA intervention is warranted based on the analysis of CCAM and the aim of promoting joint behaviors post-bariatric surgery.

4.
Front Nutr ; 11: 1364739, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38757131

RESUMO

Intestine is responsible for nutrients absorption and plays a key role in defending against various dietary allergens, antigens, toxins, and pathogens. Accumulating evidence reported a critical role of intestine in maintaining animal and human health. Since the use of antibiotics as growth promoters in animal feed has been restricted in many countries, alternatives to antibiotics have been globally investigated, and polysaccharides are considered as environmentally friendly and promising alternatives to improve intestinal health, which has become a research hotspot due to its antibiotic substitution effect. Astragalus polysaccharide (APS), a biological macromolecule, is extracted from astragalus and has been reported to exhibit complex biological activities involved in intestinal barrier integrity maintenance, intestinal microbiota regulation, short-chain fatty acids (SCFAs) production, and immune response regulation, which are critical for intestine health. The biological activity of APS is related to its chemical structure. In this review, we outlined the source and structure of APS, highlighted recent findings on the regulation of APS on physical barrier, biochemical barrier, immunological barrier, and immune response as well as the latest progress of APS as an antibiotic substitute in animal production. We hope this review could provide scientific basis and new insights for the application of APS in nutrition, clinical medicine and health by understanding particular effects of APS on intestine health, anti-inflammation, and animal production.

5.
Rapid Commun Mass Spectrom ; 38(11): e9740, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38567573

RESUMO

RATIONALE: The mass spectra of compounds containing dimethyl (phenyl)silyl group (-SiMe2Ph) sometimes exhibit unusual ion peaks when measured using Orbitrap gas chromatography-mass spectrometry (GC-MS). This would complicate the mass spectra and may limit the matching of spectral data with preexisting resources for compound annotation. These peaks were identified as products from reactions with residual water. METHODS: A series of dimethyl (phenyl)silyl compounds were dissolved in methanol and investigated using Orbitrap GC-MS. Certain ions reacted with residual water in the C-trap. The reaction was confirmed using accurate mass and elemental composition analysis via MS studies, and the active center of the reaction was determined using density functional theory (DFT) calculations. RESULTS: Two types of gas-phase reactions between gaseous water and cations from a series of silanes were identified. DFT calculations indicate that silicon (Si) acts as the active center for these gas-phase water reactions. Compounds with multiple Si atoms generate a larger number of additional ions, which would complicate the mass spectra. The mass spectra of vinylsilanes and alkylsilanes with -SiMe2Ph indicate that the conjugated group linked to -SiMe2Ph can affect the water adduction process. CONCLUSIONS: Silane ions could react with residual water in the C-trap of an Orbitrap mass spectrometer. The mass spectra of these compounds may exhibit unexplained peaks arising from gas-phase reactions. Although these reactions may decrease spectral matching scores for compound annotation, they offer opportunities for systematic investigations into the mechanistic and kinetic aspects of high-energy ion reactivity.

6.
World J Clin Cases ; 12(8): 1422-1429, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38576804

RESUMO

BACKGROUND: Pulmonary mucoepidermoid carcinoma (PMEC) is a rare malignancy that arises from minor salivary glands within the tracheobronchial tree. The clear cell variant of PMEC is exceptionally uncommon and presents notable diagnostic challenges, primarily attributable to its morphological similarity to other tumors containing clear cells. CASE SUMMARY: A 22-year-old male, formerly in good health, came in with a two-month duration of persistent cough and production of sputum. Subsequent imaging and bronchoscopy examinations revealed a 2 cm tumor in the distal left main bronchus, which resulted in complete atelectasis of the left lung. Further assessment via positron emission tomography/computed tomography scans and endoscopic biopsy confirmed the primary malignant nature of the tumor, characterized by clear cell morphology in most of the tumor cells. The patient underwent a left lower lobe sleeve resection accompanied by systematic mediastinal lymph node dissection. Molecular pathology analysis subsequently revealed a CRTC3-MAML2 gene fusion, leading to a definitive pathological diagnosis of the clear cell variant of PMEC, staged as T2N0M0. After surgery, the patient experienced a smooth recovery and exhibited no signs of recurrence during the one-and-a-half-year follow-up period. CONCLUSION: This article describes an unusual case of a clear cell variant of PMEC characterized by the presence of a CRTC3-MAML2 gene fusion in a 22-year-old male. The patient underwent successful left lower lobe sleeve resection. This case underscores the distinctive challenges associated with diagnosing and treating this uncommon malignancy, underscoring the importance of precise diagnosis and personalized treatment strategies.

7.
World J Gastrointest Surg ; 16(3): 700-709, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38577087

RESUMO

BACKGROUND: Gastric cancer (GC) is the fifth most common type of cancer and has the fourth highest death rate among all cancers. There is a lack of studies examining the impact of liver metastases on the effectiveness of immunotherapy in individuals diagnosed with GC. AIM: To investigate the influence of liver metastases on the effectiveness and safety of immunotherapy in patients with advanced GC. METHODS: This retrospective investigation collected clinical data of patients with advanced stomach cancer who had immunotherapy at our hospital from February 2021 to January 2023. The baseline attributes were compared using either the Chi-square test or the Fisher exact probability method. The chi-square test and Kaplan-Meier survival analysis were employed to assess the therapeutic efficacy and survival duration in GC patients with and without liver metastases. RESULTS: The analysis comprised 48 patients diagnosed with advanced GC, who were categorized into two groups: A liver metastasis cohort (n = 20) and a non-liver metastatic cohort (n = 28). Patients with liver metastasis exhibited a more deteriorated physical condition compared to those without liver metastasis. The objective response rates in the cohort with metastasis and the cohort without metastasis were 15.0% and 35.7% (P > 0.05), respectively. Similarly, the disease control rates in these two cohorts were 65.0% and 82.1% (P > 0.05), respectively. The median progression-free survival was 5.0 months in one group and 11.2 months in the other group, with a hazard ratio of 0.40 and a significance level (P) less than 0.05. The median overall survival was 12.0 months in one group and 19.0 months in the other group, with a significance level (P) greater than 0.05. CONCLUSION: Immunotherapy is less effective in GC patients with liver metastases compared to those without liver metastasis.

8.
Org Lett ; 26(15): 3043-3047, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38578846

RESUMO

We disclose a deconstructive [5 + 1] annulation protocol for the synthesis of isoquinolones through a nitrogen insertion into abundant indanones. This method exploits photoredox-catalyzed ring-opening of oxime esters. The reaction proceeds smoothly with water as the reaction medium and tolerates a range of functional groups on diverse thiophenols, amines, or indanones. Moreover, the representative isoquinolones exhibit promising antifungal activities.

9.
Mol Neurobiol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38632152

RESUMO

Gut microbiota has been confirmed to be closely related to Alzheimer's disease (AD). Research on gut microbiota and AD has also increased significantly. This study aimed to conduct a bibliometric and visual analysis of published studies related to gut microbiota and AD. Based on the Web of Science Core Collection SCI-Expanded database, we utilize Excel 2019 and visualization analysis tools VOSviewer, Co-Occurrence13.2 (COOC13.2), Citespace, HistCite, and Bibliometrix (R-Tool of R-Studio) for analysis. A total of 1093 related kinds of literature were included, and the number of papers presented an overall increasing trend. The country/region with the most publications is China, the institution is Zhejiang University, the author is Walter J Lukiw from the USA, and the journal is the Journal of Alzheimer's Disease. Hotspot research areas include the relationship between gut microbiota metabolism and AD, AD treatments related to the gut microbiota, and diseases related to AD and gut microbiota. The future research direction may be T cells, NLRP3 inflammasome, and Porphyromonas gingivalis. Studies on AD and gut microbiota have grown rapidly in recent years. Our research results may provide valuable references for readers and help researchers better find new research directions in the future.

10.
Ther Adv Neurol Disord ; 17: 17562864241239117, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38616782

RESUMO

Multiple sclerosis (MS) was defined as a rare disease in China due to its low prevalence. For a long time, interferon ß was the only approved disease-modifying therapy (DMT). Since the first oral DMT was approved in 2018, DMT approval accelerated, and seven DMTs were approved within 5 years. With an increasing number of DMTs being prescribed in clinical practice, it is necessary to discuss the standardized MS treatment algorithms depending on the disease activity and DMT availability. In this review paper, more than 20 Chinese experts in MS have reviewed the therapeutic progress of MS in China and worldwide and discussed algorithms for treating relapsing MS (RMS) based on the available DMTs in China, providing insights for establishing the standardized RMS treatment algorithms in this country.


Treatment algorithms of relapsing multiple sclerosis in China In this review paper, more than 20 Chinese experts in MS have reviewed the therapeutic progress of MS in China and worldwide and discussed algorithms for treating relapsing MS (RMS) based on the available DMTs in China, providing insights for establishing the standardized RMS treatment algorithms in this country: 1) CIS and RRMS account for more than 90% of the MS patients and most of them are mild to moderate; 2) MS patients should initiate DMT treatments as soon as the disease has been diagnosed in order to reduce the risk of disease progression; 3) Patients who have been diagnosed with MS should start treatment with fundamental DMTs unless the disease course has been highly active; 4) MAGNIMS score may be a suitable and simplified assessment tool for measuring treatment response to DMTs; 5) Patients treated with corticosteroids and NSIS should be switched to the standardized DMT treatment during remission in accordance with disease activity.

12.
Org Lett ; 26(17): 3581-3585, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38661063

RESUMO

A radical fluorosulfonyl arylation of alkynes with sulfuryl chlorofluoride as the FSO2 radical precursor via electron donor-acceptor photoactivation driven by daylight or a blue light-emitting diode is disclosed. A series of valuable benzo-fused carbocycles and heterocycles have been produced with simple operation under mild conditions in the absence of any external catalysts or additives. The synthetic potential of this protocol has further demonstrated excellent scalability, as well as diverse postderivatizations, including SuFEx reactions and other useful cascade reactions.

13.
Angew Chem Int Ed Engl ; : e202402774, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38584586

RESUMO

Currently, most photoredox catalysis polymerization systems are limited by high excitation power, long polymerization time, or the requirement of electron donors due to the precise design of efficient photocatalysts still poses a great challenge. Herein, we propose a new approach: the creation of efficient photocatalysts having low ground state oxidation potentials and high excited state energy levels, along with through-space charge transfer (TSCT) induced intersystem crossing (ISC) properties. A cabazole-naphthalimide (NI) dyad (NI-1) characterized by long triplet excited state lifetime (τT=62 µs), satisfactory ISC efficiency (ΦΔ=54.3 %) and powerful reduction capacity [Singlet: E1/2 (PC+1/*PC)=-1.93 eV, Triplet: E1/2 (PC+1/*PC)=-0.84 eV] was obtained. An efficient and rapid polymerization (83 % conversion of 1 mM monomer in 30 s) was observed under the conditions of without electron donor, low excitation power (10 mW cm-2) and low catalyst (NI-1) loading (<50 µM). In contrast, the conversion rate was lower at 29 % when the reference catalyst (NI-4) was used for photopolymerization under the same conditions, demonstrating the advantage of the TSCT photocatalyst. Finally, the TSCT material was used as a photocatalyst in practical lithography for the first time, achieving pattern resolutions of up to 10 µm.

14.
BMC Neurol ; 24(1): 137, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664621

RESUMO

BACKGROUND: Scrub typhus is an acute infectious disease caused by Orientia tsutsugamushi. Guillain-Barre syndrome (GBS) is an autoimmune-mediated peripheral neuropathy with a frequent history of prodromal infections, but GBS associated with scrub typhus is very rare. CASE PRESENTATION: We report a 51-year-old male patient who developed dysarthria and peripheral facial paralysis following the cure of scfrub typhus. CSF examination and electrophysiological findings suggested a diagnosis of GBS. After treatment with intravenous immunoglobulin, the patient's neurological condition improved rapidly. CONCLUSIONS: Scrub typhus infection is likely to be a potential predisposing factor in GBS, while scrub typhus-associated GBS has a favorable prognosis.


Assuntos
Síndrome de Guillain-Barré , Tifo por Ácaros , Humanos , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/tratamento farmacológico , Tifo por Ácaros/complicações , Tifo por Ácaros/diagnóstico , Tifo por Ácaros/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Imunoglobulinas Intravenosas/uso terapêutico
15.
Aging (Albany NY) ; 16(7): 6588-6612, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38604156

RESUMO

BACKGROUND: Liver progenitor cells (LPCs) are a subpopulation of cells that contribute to liver regeneration, fibrosis and liver cancer initiation under different circumstances. RESULTS: By performing adenoviral-mediated transfection, CCK-8 analyses, F-actin staining, transwell analyses, luciferase reporter analyses and Western blotting, we observed that TGF-ß promoted cytostasis and partial epithelial-mesenchymal transition (EMT) in LPCs. In addition, we confirmed that TGF-ß activated the Smad and MAPK pathways, including the Erk, JNK and p38 MAPK signaling pathways, and revealed that TGFß-Smad signaling induced growth inhibition and partial EMT, whereas TGFß-MAPK signaling had the opposite effects on LPCs. We further found that the activity of Smad and MAPK signaling downstream of TGF-ß was mutually restricted in LPCs. Mechanistically, we found that TGF-ß activated Smad signaling through serine phosphorylation of both the C-terminal and linker regions of Smad2 and 3 in LPCs. Additionally, TGFß-MAPK signaling inhibited the phosphorylation of Smad3 but not Smad2 at the C-terminus, and it reinforced the linker phosphorylation of Smad3 at T179 and S213. We then found that overexpression of mutated Smad3 at linker phosphorylation sites intensifies TGF-ß-induced cytostasis and EMT, mimicking the effects of MAPK inhibition in LPCs, whereas mutation of Smad3 at the C-terminus caused LPCs to blunt TGF-ß-induced cytostasis and partial EMT. CONCLUSION: These results suggested that TGF-ß downstream of Smad3 and MAPK signaling were mutually antagonistic in regulating the viability and partial EMT of LPCs. This antagonism may help LPCs overcome the cytostatic effect of TGF-ß under fibrotic conditions and maintain partial EMT and progenitor phenotypes.


Assuntos
Transição Epitelial-Mesenquimal , Fígado , Sistema de Sinalização das MAP Quinases , Proteína Smad3 , Células-Tronco , Fator de Crescimento Transformador beta , Proteína Smad3/metabolismo , Células-Tronco/metabolismo , Animais , Fator de Crescimento Transformador beta/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Fígado/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Fosforilação , Camundongos , Transdução de Sinais
16.
J Phys Condens Matter ; 36(31)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38657636

RESUMO

We investigate the magnetic and transport properties of a kagome magnet YbMn6Sn6. We have grown YbMn6Sn6single crystals having a HfFe6Ge6type structure with ordered Yb and Sn atoms, which is different from the distorted structure previously reported. The single crystal undergoes a ferromagnetic phase transition around 300 K and a ferrimagnetic transition at approximately 30 K, and the magnetic transition at low temperature may be correlated to the ordered Yb sublattice. Negative magnetoresistance has been observed at high temperatures, while the positive magnetoresistance appears at 5 K when the current is oriented out of kagome plane. We observe a large anisotropic anomalous Hall effect with the intrinsic Hall contribution of 141 Ω-1cm-1forσzxintand 32 Ω-1cm-1forσxyint, respectively. These values are similar to those in YMn6Sn6with the same anisotropy. The magnetic transition and anomalous Hall behavior in YbMn6Sn6highlights the influence of the ordered Yb atoms and rare earth elements on its magnetic and transport properties.

17.
BMC Cardiovasc Disord ; 24(1): 186, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539102

RESUMO

BACKGROUND: The cardiometabolic index (CMI) is a new metric derived from the triglyceride-glucose index and body mass index and is considered a potential marker for cardiovascular risk assessment. This study aimed to examine the correlation between the CMI and the presence and severity of arteriosclerosis in patients with type 2 diabetes mellitus (T2DM). METHODS: This study involved 2243 patients with T2DM. The CMI was derived by dividing the triglyceride level (mmol/L) by the high-density lipoprotein level (mmol/L) and then multiplying the quotient by the waist-to-height ratio. Multivariate logistic regression was used to analyze the correlations between the CMI and BMI blood biomarkers, blood pressure, and brachial-ankle pulse wave velocity (baPWV). RESULTS: Patients were categorized into three groups based on their CMI: Group C1 (CMI < 0.775; n = 750), Group C2 (CMI: 0.775-1.355; n = 743), and Group C3 (CMI > 1.355; n = 750). Increased BMI, fasting glucose, insulin (at 120 min), total cholesterol (TC), and baPWV values were observed in Groups C2 and C3, with statistically significant trends (all trends P < 0.05). The CMI was positively correlated with systolic blood pressure (r = 0.74, P < 0.001). Multivariate analysis revealed that an increased CMI contributed to a greater risk for arteriosclerosis (OR = 1.87, 95%CI: 1.66-2.10, P < 0.001). Compared to the C1 group, the C2 group and C3 group had a greater risk of developing arteriosclerosis, with ORs of 4.55 (95%CI: 3.57-5.81, P<0.001) and 5.56 (95%CI: 4.32-7.17, P<0.001), respectively. The association was notably stronger in patients with a BMI below 21.62 kg/m² than in those with a BMI of 21.62 kg/m² or higher (OR = 4.53 vs. OR = 1.59). CONCLUSIONS: These findings suggest that the CMI is a relevant and independent marker of arteriosclerosis in patients with T2DM and may be useful in the risk stratification and management of these patients.


Assuntos
Arteriosclerose , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Índice Tornozelo-Braço , Fatores de Risco , Análise de Onda de Pulso , Arteriosclerose/diagnóstico , Índice de Massa Corporal , Triglicerídeos , Glucose
19.
J Hepatol ; 80(2): 194-208, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38438948

RESUMO

BACKGROUND & AIMS: Hepatocyte apoptosis, a well-defined form of cell death in non-alcoholic steatohepatitis (NASH), is considered the primary cause of liver inflammation and fibrosis. However, the mechanisms underlying the regulation of hepatocyte apoptosis in NASH remain largely unclear. We explored the anti-apoptotic effect of hepatocyte CD1d in NASH. METHODS: Hepatocyte CD1d expression was analyzed in patients with NASH and mouse models. Hepatocyte-specific gene overexpression or knockdown and anti-CD1d crosslinking were used to investigate the anti-apoptotic effect of hepatocyte CD1d on lipotoxicity-, Fas-, and concanavalin (ConA)-mediated liver injuries. A high-fat diet, a methionine-choline-deficient diet, a Fas agonist, and ConA were used to induce lipotoxic and/or apoptotic liver injuries. Palmitic acid was used to mimic lipotoxicity-induced apoptosis in vitro. RESULTS: We identified a dramatic decrease in CD1d expression in hepatocytes of patients with NASH and mouse models. Hepatocyte-specific CD1d overexpression and knockdown experiments collectively demonstrated that hepatocyte CD1d protected against hepatocyte apoptosis and alleviated hepatic inflammation and injuries in NASH mice. Furthermore, decreased JAK2-STAT3 signaling was observed in NASH patient livers. Mechanistically, anti-CD1d crosslinking on hepatocytes induced tyrosine phosphorylation of the CD1d cytoplasmic tail, leading to the recruitment and phosphorylation of JAK2. Phosphorylated JAK2 activated STAT3 and subsequently reduced apoptosis in hepatocytes, which was associated with an increase in anti-apoptotic effectors (Bcl-xL and Mcl-1) and a decrease in pro-apoptotic effectors (cleaved-caspase 3/7). Moreover, anti-CD1d crosslinking effectively protected against Fas- or ConA-mediated hepatocyte apoptosis and liver injury in mice. CONCLUSIONS: Our study uncovered a previously unrecognized anti-apoptotic CD1d-JAK2-STAT3 axis in hepatocytes that conferred hepatoprotection and highlighted the potential of hepatocyte CD1d-directed therapy for liver injury and fibrosis in NASH, as well as in other liver diseases associated with hepatocyte apoptosis. IMPACT AND IMPLICATIONS: Excessive and/or sustained hepatocyte apoptosis is critical in driving liver inflammation and injury. The mechanisms underlying the regulation of hepatocyte apoptosis in non-alcoholic steatohepatitis (NASH) remain largely unclear. Here, we found that CD1d expression in hepatocytes substantially decreases and negatively correlates with the severity of liver injury in patients with NASH. We further revealed a previously unrecognized anti-apoptotic CD1d-JAK2-STAT3 signaling axis in hepatocytes, which confers significant protection against liver injury in NASH and acute liver diseases. Thus, hepatocyte CD1d-targeted therapy could be a promising strategy to manipulate liver injury in both NASH and other hepatocyte apoptosis-related liver diseases.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Apoptose , Concanavalina A , Modelos Animais de Doenças , Hepatócitos , Inflamação
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