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1.
Org Biomol Chem ; 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39415722

RESUMO

As a special class of alkynes, gem-difluoromethylene alkynes exhibit a variety of fascinating properties due to the presence of the gem-difluoro substitution. This substitution highlights the distinctive fluorine effects in influencing the chemoselectivity of reactions. As a result, chemical scientists have shown great interest and enthusiasm for investigating their reactions. In this review, we briefly summarize recent advances in transition metal-catalysed reactions of gem-difluoromethylene alkynes with multiple reaction pathways. Their mechanistic studies and challenges will be highlighted. The purpose of this review is to provide illustrations of elegant gem-difluoromethylene alkynes and thereby elicit further interest among synthetic chemists in developing innovative transformations of gem-difluoromethylene alkynes.

2.
Arterioscler Thromb Vasc Biol ; 44(9): 1986-2003, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-39051127

RESUMO

BACKGROUND: Inflammation is a key component in the development of abdominal aortic aneurysm (AAA), yet insights into the roles of immune cells and their interactions in this process are limited. METHODS: Using single-cell RNA transcriptomic analysis, we deconstructed the CD45+ cell population in elastase-induced murine AAA at the single-cell level. We isolated each group of immune cells from murine AAA tissue at different time points and divided them into several subtypes, listed the remarkable differentially expressed genes, explored the developmental trajectories of immune cells, and demonstrated the interactions among them. RESULTS: Our findings reveal significant differences in several immune cell subsets, including macrophages, dendritic cells, and T cells, within the AAA microenvironment compared with the normal aorta. Especially, conventional dendritic cell type 1 exclusively existed in the AAA tissue rather than the normal aortas. Via CellChat analysis, we identified several intercellular communication pathways like visfatin, which targets monocyte differentiation and neutrophil extracellular trap-mediated interaction between neutrophils and dendritic cells, which might contribute to AAA development. Some of these pathways were validated in human AAA. CONCLUSIONS: Despite the absence of external pathogenic stimuli, AAA tissues develop a complex inflammatory microenvironment involving numerous immune cells. In-depth studies of the inflammatory network shall provide new strategies for patients with AAA.


Assuntos
Aorta Abdominal , Aneurisma da Aorta Abdominal , Células Dendríticas , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Análise de Célula Única , Aneurisma da Aorta Abdominal/imunologia , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/metabolismo , Animais , Aorta Abdominal/patologia , Aorta Abdominal/metabolismo , Aorta Abdominal/imunologia , Camundongos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Humanos , Macrófagos/metabolismo , Macrófagos/imunologia , Masculino , Transcriptoma , RNA-Seq , Linfócitos T/imunologia , Linfócitos T/metabolismo , Perfilação da Expressão Gênica/métodos , Elastase Pancreática , Comunicação Celular
3.
Poult Sci ; 103(10): 104038, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39079330

RESUMO

Fatty acids (FAs) can serve as energy for poultry, maintain normal cell structure and function, and support a healthy immune system. Although the addition of polyunsaturated fatty acids (PUFAs) to the diet has been extensively studied and reported, the mechanism of action of saturated fatty acids (SFAs) remains to be elucidated. We investigated the effect of 0.04% dietary myristic acid (MA) on slaughter performance, lipid components, tissue FAs, and the transcriptome profile in chickens. The results showed that dietary MA had no effect on slaughter performance (body weight, carcass weight, eviscerated weight, and pectoral muscle weight) (P > 0.05). Dietary MA enrichment increased MA (P < 0.001) and triglycerides (TGs) (P < 0.01) levels in the pectoral muscle. The levels of palmitic acid, linoleic acid (LA), arachidonic acid (AA), SFAs, monounsaturated fatty acids (MUFAs), and PUFAs were significantly higher (P < 0.01) in the MA supplementation group compared to the control group. However, there were no significant differences in the ratios of PUFA/SFA and n6/omega-3 (n3) between the two groups. The MA content was positively correlated with the contents of palmitic acid, LA, linolenic acid (ALA), n3, n6, SFAs, and unsaturated fatty acids (UFA). DHCR24, which is known to be involved in steroid metabolism and cholesterol biosynthesis pathways, was found to be a significantly lower in the MA supplementation group compared to the control group (P < 0.05, log2(fold change) = -0.85). Five overlapping co-expressed genes were identified at the intersection between the differential expressed genes and Weighted Gene Co­expression Network Analysis-derived hub genes associated with MA phenotype, namely BHLHE40, MSL1, PLAGL1, SRSF4, and ENSGALG00000026875. For the TG phenotype, a total of 28 genes were identified, including CHKA, KLF5, TGIF1, etc. Both sets included the gene PLAGL1, which has a negative correlation with the levels of MA and TG. This study provides valuable information to further understand the regulation of gene expression patterns by dietary supplementation with MA and examines at the molecular level the phenotypic changes induced by supplementation with MA.


Assuntos
Ração Animal , Galinhas , Dieta , Suplementos Nutricionais , Ácido Mirístico , Músculos Peitorais , Triglicerídeos , Animais , Galinhas/genética , Galinhas/fisiologia , Galinhas/metabolismo , Suplementos Nutricionais/análise , Ácido Mirístico/metabolismo , Músculos Peitorais/metabolismo , Músculos Peitorais/efeitos dos fármacos , Ração Animal/análise , Dieta/veterinária , Triglicerídeos/metabolismo , Masculino , Distribuição Aleatória , Ácidos Graxos/metabolismo , Transcriptoma/efeitos dos fármacos
4.
J Am Chem Soc ; 146(30): 21025-21033, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39025790

RESUMO

Artificial photosynthesis represents a sustainable strategy for accessing high-value chemicals; however, the conversion efficiency is significantly limited by its difficulty in the cycle of coenzymes such as NADH. In this study, we report a series of isostructural triazine covalent organic frameworks (COFs) and explore their N-substituted microenvironment-dependent photocatalytic activity for NADH regeneration. We discovered that the rational alteration of N-heterocyclic species, which are linked to the triazine center through an imine linkage, can significantly regulate both the electron band structure and planarity of a COF layer. This results in different separation efficiencies of the photoinduced electron-hole pairs and electron transfer behavior within and between individual layers. The optimal COF catalyst herein achieves an NADH regeneration capacity of 89% within 20 min, outperforming most of the reported nanomaterial photocatalysts. Based on this, an artificial photosynthesis system is constructed for the green synthesis of a high-value compound, L-glutamate, and its conversion efficiency significantly surpasses the enzymatic approach without the NADH photocatalytic cycle. This work offers new insights into the coenzyme regeneration by means of regulating the distal heterocyclic microenvironment of a COF skeleton, holding great potential for the green photosynthesis of important chemicals.


Assuntos
Estruturas Metalorgânicas , Triazinas , Triazinas/química , Catálise , Estruturas Metalorgânicas/química , NAD/química , NAD/metabolismo , Processos Fotoquímicos , Estrutura Molecular , Coenzimas/química , Coenzimas/metabolismo , Fotossíntese
5.
Science ; 384(6703): 1453-1460, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38870272

RESUMO

Insects detect and discriminate a diverse array of chemicals using odorant receptors (ORs), which are ligand-gated ion channels comprising a divergent odorant-sensing OR and a conserved odorant receptor co-receptor (Orco). In this work, we report structures of the ApOR5-Orco heterocomplex from the pea aphid Acyrthosiphon pisum alone and bound to its known activating ligand, geranyl acetate. In these structures, three ApOrco subunits serve as scaffold components that cannot bind the ligand and remain relatively unchanged. Upon ligand binding, the pore-forming helix S7b of ApOR5 shifts outward from the central pore axis, causing an asymmetrical pore opening for ion influx. Our study provides insights into odorant recognition and channel gating of the OR-Orco heterocomplex and offers structural resources to support development of innovative insecticides and repellents for pest control.


Assuntos
Acetatos , Afídeos , Proteínas de Insetos , Receptores Odorantes , Receptores Odorantes/química , Receptores Odorantes/metabolismo , Receptores Odorantes/genética , Animais , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Afídeos/química , Acetatos/química , Acetatos/metabolismo , Ligantes , Terpenos/química , Terpenos/metabolismo , Odorantes/análise , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Ativação do Canal Iônico , Microscopia Crioeletrônica , Monoterpenos Acíclicos
6.
Sci Total Environ ; 945: 173861, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38871323

RESUMO

Coastal wetlands are key players in mitigating global climate change by sequestering soil organic matter. Soil organic matter consists of less stable particulate organic matter (POM) and more stable mineral-associated organic matter (MAOM). The distribution and drivers of MAOM and POM in coastal wetlands have received little attention, despite the processes and mechanisms differ from that in the upland soils. We explored the distribution of POM and MAOM, their contributions to SOM, and the controlling factors along a salinity gradient in an estuarine wetland. In the estuarine wetland, POM C and N were influenced by soil depth and vegetation type, whereas MAOM C and N were influenced only by vegetation type. In the estuarine wetland, SOM was predominantly in the form of MAOM (> 70 %) and increased with salinity (70 %-76 %), leading to long-term C sequestration. Both POM and MAOM increased with SOM, and the increase rate of POM was higher than that of MAOM. Aboveground plant biomass decreased with increasing salinity, resulted in a decrease in POM C (46 %-81 %) and N (52 %-82 %) pools. As the mineral amount and activity, and microbial biomass decreased, the MAOM C (2.5 %-64 %) and N pool (8.6 %-59 %) decreased with salinity. When evaluating POM, the most influential factors were microbial biomass carbon (MBC) and dissolved organic carbon (DOC). Key parameters, including MBC, DOC, soil salinity, soil water content, aboveground plant biomass, mineral content and activity, and bulk density, were identified as influencing factors for both MAOM abundance. Soil water content not only directly controlled MAOM, but together with salinity also indirectly regulated POM and MAOM by controlling microbial biomass and aboveground plant biomass. Our findings have important implications for improving the accumulation and increased stability of soil organic matter in coastal wetlands, considering the global sea level rise and increased frequency of inundation.

7.
Cell Death Differ ; 31(9): 1140-1156, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38816578

RESUMO

There is a lack of effective treatments to overcome resistance to EGFR-TKIs in EGFR mutant tumors. A deeper understanding of resistance mechanisms can provide insights into reducing or eliminating resistance, and can potentially deliver targeted treatment measures to overcome resistance. Here, we identified that the dynamic changes of the tumor immune environment were important extrinsic factors driving tumor resistance to EGFR-TKIs in EGFR mutant cell lines and syngeneic tumor-bearing mice. Our results demonstrate that the acquired resistance to EGFR-TKIs is accompanied by aberrant expression of PD-L2, leading a dynamic shift from an initially favorable tumor immune environment to an immunosuppressive phenotype. PD-L2 expression significantly affected EGFR mutant cell apoptosis that depended on the proportion and function of CD8+ T cells in the tumor immune environment. Combined with single-cell sequencing and experimental results, we demonstrated that PD-L2 specifically inhibited the proliferation of CD8+ T cells and the secretion of granzyme B and perforin, leading to reduced apoptosis mediated by CD8+ T cells and enhanced immune escape of tumor cells, which drives EGFR-TKIs resistance. Importantly, we have identified a potent natural small-molecule inhibitor of PD-L2, zinc undecylenate. In vitro, it selectively and potently blocks the PD-L2/PD-1 interaction. In vivo, it abolishes the suppressive effect of the PD-L2-overexpressing tumor immune microenvironment by blocking PD-L2/PD-1 signaling. Moreover, the combination of zinc undecylenate and EGFR-TKIs can synergistically reverse tumor resistance, which is dependent on CD8+ T cells mediating apoptosis. Our study uncovers the PD-L2/PD-1 signaling pathway as a driving factor to mediate EGFR-TKIs resistance, and identifies a new naturally-derived agent to reverse EGFR-TKIs resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Proteína 2 Ligante de Morte Celular Programada 1 , Microambiente Tumoral , Animais , Feminino , Humanos , Camundongos , Apoptose/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inibidores , Terapia de Alvo Molecular , Proteína 2 Ligante de Morte Celular Programada 1/metabolismo , Proteína 2 Ligante de Morte Celular Programada 1/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos
8.
Naunyn Schmiedebergs Arch Pharmacol ; 397(10): 7995-8007, 2024 10.
Artigo em Inglês | MEDLINE | ID: mdl-38767671

RESUMO

Activation of the renin-angiotensin system (RAS) triggers oxidative stress and an inflammatory response in the hypothalamic paraventricular nucleus (PVN), in turn increasing the sympathetic hyperactivity that is a major cause of hypertension. Pyridostigmine has cardioprotective effects by suppressing the RAS of myocardial tissue. However, whether pyridostigmine attenuates hypertension by inhibiting the RAS of the PVN remains unclear. We thus investigated the effect and mechanism of pyridostigmine on two-kidney one-clip (2K1C)-induced hypertension. 2K1C rats received pyridostigmine, or not, for 8 weeks. Cardiovascular function, hemodynamic parameters, and autonomic activity were measured. The PVN levels of pro-/anti-inflammatory cytokines, oxidative stress, and RAS signaling molecules were evaluated. Our results showed that hypertension was accompanied by cardiovascular dysfunction and an autonomic imbalance characterized by enhanced sympathetic but diminished vagal activity. The PVN levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), reactive oxygen species (ROS), NOX-2, and malondialdehyde (MDA) increased; those of IL-10 and superoxide dismutase (SOD) decreased. Moreover, the RAS signaling pathway was activated, as evidenced by increased levels of the angiotensin-converting enzyme (ACE), angiotensin II (Ang II), and the Ang II type 1 receptor (AT1R) and a decreased AT2R level. Pyridostigmine lowered blood pressure and improved cardiovascular function, associated with restoration of the autonomic balance. Meanwhile, pyridostigmine decreased PVN IL-6, TNF-α, ROS, NOX-2, and MDA levels and increased IL-10 and SOD levels. Additionally, pyridostigmine suppressed PVN ACE, Ang II, and AT1R levels and increased AT2R expression. Pyridostigmine attenuated hypertension by inhibiting PVN oxidative stress and inflammation induced by the RAS.


Assuntos
Hipertensão , Estresse Oxidativo , Núcleo Hipotalâmico Paraventricular , Brometo de Piridostigmina , Ratos Sprague-Dawley , Sistema Renina-Angiotensina , Animais , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/metabolismo , Sistema Renina-Angiotensina/efeitos dos fármacos , Masculino , Brometo de Piridostigmina/farmacologia , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Hipertensão/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Citocinas/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Angiotensina II , NADPH Oxidase 2/metabolismo
9.
Asian J Surg ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760222

RESUMO

OBJECTIVES: Intraoperative frozen section (FS) analysis is pivotal in guiding surgical interventions for early-stage lung adenocarcinoma. However, the challenge arises when distinguishing between Minimally Invasive Adenocarcinoma (MIA) and Invasive Adenocarcinoma (IAC) poses diagnostic difficulties. This study investigates the prognosis and clinicopathological characteristics of patients encountering this diagnostic challenge. METHODS: We conducted a retrospective analysis of 7082 intraoperative FSs from early-stage lung adenocarcinoma cases. The cases with pulmonary nodules within 3 cm and diagnosed as indeterminate FSs were included. We analyzed baseline data, computed tomography (CT) findings, and pathological characteristics. Prognostic data were obtained from patients with confirmed IAC diagnoses through final pathological examination. RESULTS: Out of 7082 FSs, 551 cases presented challenges in distinguishing between MIA and IAC. Upon final pathological examination, 233 cases were identified as IAC, while 314 were classified as MIA. The median invasive pathological size in the IAC group was larger than that in the MIA group (0.6 cm vs 0.3 cm). 131 cases (56.2 %) with IAC underwent lobectomy, while 102 cases (43.8 %) underwent sub-lobar resection. Among the MIA cases, 220 cases (69.8 %) underwent sub-lobar resection, while 95 cases (30.2 %) underwent lobectomy. No recurrence and disease specific death was observed during the follow-up period, regardless of surgical strategy. CONCLUSIONS: Indeterminate intraoperative FSs, posing diagnostic challenges in distinguishing between MIA and IAC. Sub-lobar resection presented the same long term survival benefit compared with the lobectomy for indeterminate lung adenocarcinoma within 3 cm during intraoperative FSs.

10.
New Phytol ; 242(5): 1996-2010, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38571393

RESUMO

The conquest of land by plants was concomitant with, and possibly enabled by, the evolution of three-dimensional (3D) growth. The moss Physcomitrium patens provides a model system for elucidating molecular mechanisms in the initiation of 3D growth. Here, we investigate whether the phytohormone ethylene, which is believed to have been a signal before land plant emergence, plays a role in 3D growth regulation in P. patens. We report ethylene controls 3D gametophore formation, based on results from exogenously applied ethylene and genetic manipulation of PpEIN2, which is a central component in the ethylene signaling pathway. Overexpression (OE) of PpEIN2 activates ethylene responses and leads to earlier formation of gametophores with fewer gametophores produced thereafter, phenocopying ethylene-treated wild-type. Conversely, Ppein2 knockout mutants, which are ethylene insensitive, show initially delayed gametophore formation with more gametophores produced later. Furthermore, pharmacological and biochemical analyses reveal auxin levels are decreased in the OE lines but increased in the knockout mutants. Our results suggest that evolutionarily, ethylene and auxin molecular networks were recruited to build the plant body plan in ancestral land plants. This might have played a role in enabling ancient plants to acclimate to the continental surfaces of the planet.


Assuntos
Bryopsida , Etilenos , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Proteínas de Plantas , Etilenos/metabolismo , Ácidos Indolacéticos/metabolismo , Ácidos Indolacéticos/farmacologia , Bryopsida/crescimento & desenvolvimento , Bryopsida/genética , Bryopsida/efeitos dos fármacos , Bryopsida/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Células Germinativas Vegetais/metabolismo , Células Germinativas Vegetais/crescimento & desenvolvimento , Células Germinativas Vegetais/efeitos dos fármacos , Mutação/genética
11.
Org Lett ; 26(16): 3355-3360, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38604973

RESUMO

A two-step protocol for the conversion of alkyl-substituted alkynes to 1,3-enynes is reported. In this α-methenylation process, an iron-catalyzed propargylic C-H functionalization delivers tetramethylpiperidine-derived homopropargylic amines which undergo facile Cope elimination upon N-oxidation to afford the enyne products. A range of aryl alkyl and dialkyl acetylenes were found to be suitable substrates for this process, which constitutes an alkyne analogue for the Eschenmoser methenylation of carbonyl derivatives. In addition, a new bench-stable precatalyst for iron-catalyzed propargylic C-H functionalization is reported.

12.
Lipids Health Dis ; 23(1): 117, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649999

RESUMO

Metabolic dysfunction-associated steatotic liver disease (MASLD) has garnered considerable attention globally. Changing lifestyles, over-nutrition, and physical inactivity have promoted its development. MASLD is typically accompanied by obesity and is strongly linked to metabolic syndromes. Given that MASLD prevalence is on the rise, there is an urgent need to elucidate its pathogenesis. Hepatic lipid accumulation generally triggers lipotoxicity and induces MASLD or progress to metabolic dysfunction-associated steatohepatitis (MASH) by mediating endoplasmic reticulum stress, oxidative stress, organelle dysfunction, and ferroptosis. Recently, significant attention has been directed towards exploring the role of gut microbial dysbiosis in the development of MASLD, offering a novel therapeutic target for MASLD. Considering that there are no recognized pharmacological therapies due to the diversity of mechanisms involved in MASLD and the difficulty associated with undertaking clinical trials, potential targets in MASLD remain elusive. Thus, this article aimed to summarize and evaluate the prominent roles of lipotoxicity, ferroptosis, and gut microbes in the development of MASLD and the mechanisms underlying their effects. Furthermore, existing advances and challenges in the treatment of MASLD were outlined.


Assuntos
Estresse do Retículo Endoplasmático , Ferroptose , Microbioma Gastrointestinal , Humanos , Estresse Oxidativo , Disbiose/complicações , Disbiose/microbiologia , Animais , Fígado Gorduroso/metabolismo , Metabolismo dos Lipídeos , Obesidade/metabolismo , Obesidade/complicações , Obesidade/patologia , Fígado/metabolismo , Fígado/patologia , Síndrome Metabólica/metabolismo
13.
EMBO Mol Med ; 16(4): 885-903, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38448544

RESUMO

Cancer is a heterogeneous disease. Although both tumor metabolism and tumor immune microenvironment are recognized as driving factors in tumorigenesis, the relationship between them is still not well-known, and potential combined targeting approaches remain to be identified. Here, we demonstrated a negative correlation between the expression of NAMPT, an NAD+ metabolism enzyme, and PD-L1 expression in various cancer cell lines. A clinical study showed that a NAMPTHigh PD-L1Low expression pattern predicts poor prognosis in patients with various cancers. In addition, pharmacological inhibition of NAMPT results in the transcription upregulation of PD-L1 by SIRT-mediated acetylation change of NF-κB p65, and blocking PD-L1 would induce NAMPT expression through a HIF-1-dependent glycolysis pathway. Based on these findings, we designed and synthesized a dual NAMPT/PD-L1 targeting compound, LZFPN-90, which inhibits cell growth in a NAMPT-dependent manner and blocks the cell cycle, subsequently inducing apoptosis. Under co-culture conditions, LZFPN-90 treatment contributes to the proliferation and activation of T cells and blocks the growth of cancer cells. Using mice bearing genetically manipulated tumors, we confirmed that LZFPN-90 exerted target-dependent antitumor activities, affecting metabolic processes and the immune system. In conclusion, our results demonstrate the relevance of NAD+-related metabolic processes in antitumor immunity and suggest that co-targeting NAD+ metabolism and PD-L1 represents a promising therapeutic approach.


Assuntos
Antígeno B7-H1 , Neoplasias , Humanos , Animais , Camundongos , NAD , Neoplasias/patologia , Proliferação de Células , Apoptose , Linhagem Celular Tumoral , Microambiente Tumoral
14.
J Hepatol ; 81(1): 135-148, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38460791

RESUMO

BACKGROUND & AIMS: NOTCH signaling in liver sinusoidal endothelial cells (LSECs) regulates liver fibrosis, a pathological feature of chronic liver diseases. POFUT1 is an essential regulator of NOTCH signaling. Here, we investigated the role of LSEC-expressed POFUT1 in liver fibrosis. METHODS: Endothelial-specific Pofut1 knockout mice were generated and experimental liver fibrosis was induced by chronic carbon tetrachloride exposure or common bile duct ligation. Liver samples were assessed by ELISA, histology, electron microscopy, immunostaining and RNA in situ hybridization. LSECs and hepatic stellate cells (HSCs) were isolated for gene expression analysis by RNA sequencing, qPCR, and western blotting. Signaling crosstalk between LSECs and HSCs was investigated by treating HSCs with supernatant from LSEC cultures. Liver single-cell RNA sequencing datasets from patients with cirrhosis and healthy individuals were analyzed to evaluate the clinical relevance of gene expression changes observed in mouse studies. RESULTS: POFUT1 loss promoted injury-induced LSEC capillarization and HSC activation, leading to aggravated liver fibrosis. RNA sequencing analysis revealed that POFUT1 deficiency upregulated fibrinogen expression in LSECs. Consistently, fibrinogen was elevated in LSECs of patients with cirrhosis. HSCs treated with supernatant from LSECs of Pofut1 null mice showed exacerbated activation compared to those treated with supernatant from control LSECs, and this effect was attenuated by knockdown of fibrinogen or by pharmacological inhibition of fibrinogen receptor signaling, altogether suggesting that LSEC-derived fibrinogen induced the activation of HSCs. Mechanistically, POFUT1 loss augmented fibrinogen expression by enhancing NOTCH/HES1/STAT3 signaling. CONCLUSIONS: Endothelial POFUT1 prevents injury-induced liver fibrosis by repressing the expression of fibrinogen, which functions as a profibrotic paracrine signal to activate HSCs. Therapies targeting the POFUT1/fibrinogen axis offer a promising strategy for the prevention and treatment of fibrotic liver diseases. IMPACT AND IMPLICATIONS: Paracrine signals produced by liver vasculature play a major role in the development of liver fibrosis, which is a pathological hallmark of most liver diseases. Identifying those paracrine signals is clinically relevant in that they may serve as therapeutic targets. In this study, we discovered that genetic deletion of Pofut1 aggravated experimental liver fibrosis in mouse models. Moreover, fibrinogen was identified as a downstream target repressed by Pofut1 in liver endothelial cells and functioned as a novel paracrine signal that drove liver fibrosis. In addition, fibrinogen was found to be relevant to cirrhosis and may serve as a potential therapeutic target for this devastating human disease.


Assuntos
Células Endoteliais , Fibrinogênio , Células Estreladas do Fígado , Cirrose Hepática , Camundongos Knockout , Animais , Humanos , Masculino , Camundongos , Tetracloreto de Carbono/toxicidade , Tetracloreto de Carbono/efeitos adversos , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Fibrinogênio/metabolismo , Fibrinogênio/biossíntese , Fibrinogênio/genética , Células Estreladas do Fígado/metabolismo , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/genética , Receptores Notch/metabolismo , Receptores Notch/fisiologia , Transdução de Sinais
15.
Glob Chang Biol ; 30(3): e17213, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38436125

RESUMO

Paddy fields serve as significant reservoirs of soil organic carbon (SOC) and their potential for terrestrial carbon (C) sequestration is closely associated with changes in SOC pools. However, there has been a dearth of comprehensive studies quantifying changes in SOC pools following extended periods of rice cultivation across a broad geographical scale. Using 104 rice paddy sampling sites that have been in continuous cultivation since the 1980s across China, we studied the changes in topsoil (0-20 cm) labile organic C (LOC I), semi-labile organic C (LOC II), recalcitrant organic C (ROC), and total SOC. We found a substantial increase in both the content (48%) and density (39%) of total SOC within China's paddy fields between the 1980s to the 2010s. Intriguingly, the rate of increase in content and density of ROC exceeded that of LOC (I and II). Using a structural equation model, we revealed that changes in the content and density of total SOC were mainly driven by corresponding shifts in ROC, which are influenced both directly and indirectly by climatic and soil physicochemical factors; in particular temperature, precipitation, phosphorous (P) and clay content. We also showed that the δ13 CLOC were greater than δ13 CROC , independent of the rice cropping region, and that there was a significant positive correlation between δ13 CSOC and δ13 Cstraw . The δ13 CLOC and δ13 CSOC showed significantly negative correlation with soil total Si, suggesting that soil Si plays a part in the allocation of C into different SOC pools, and its turnover or stabilization. Our study underscores that the global C sequestration of the paddy fields mainly stems from the substantial increase in ROC pool.


Assuntos
Oryza , Solo , Carbono , China , Geografia
16.
Huan Jing Ke Xue ; 45(3): 1512-1524, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471866

RESUMO

It is important to explore the relationship between land use types and water quality to improve the surface water environment. Based on monthly water quality monitoring data from 16 nationally controlled surface water quality monitoring stations in Tianjin and land use data in 2021, GIS spatial analysis and mathematical and statistical methods were used to study the influence of land use types on surface water quality in buffer zones at different scales. The results showed that:① the land use types in the study area were mainly construction land, farmland, and water areas, which had significant effects on river water quality. Except for water temperature (WT) and pH, the farmland, construction land, and water areas were negatively correlated with each water quality indicator; forest land and grassland were positively correlated with dissolved oxygen (DO) and total nitrogen (TN) and negatively correlated with other water quality indicators. ② The water quality indicators showed obvious spatial differences in different seasons. The pH, DO and TN concentrations were higher in the dry season, whereas the permanganate index, ammonia nitrogen (NH4+-N), and total phosphorus (TP) concentrations were higher in the rainy season. ③ The results of the RDA analysis showed that the 800 m buffer zone land use had the greatest explanatory power for water quality changes in the dry season (50.4%), whereas the 3 000 m buffer zone land use could explain the water quality changes in the rainy season to the greatest extent (49.6%); from the average explanation rate of the dry and rainy seasons, the 3 000 m buffer zone was the best impact scale (50.0%) on water quality indicators in Tianjin. ④ The partial least squares regression (PLSR) analysis showed that the most important variables affecting surface water quality changes were construction land, farmland, and water areas. The predictive ability of the PLSR model of most water quality indicators was stronger in the dry season than that in the rainy season. In the dry season, all water quality indicators, except WT and pH, were most influenced by farmland. In the rainy season, construction land had the greatest influence on WT and NH4+-N concentrations, and the most important influencing factor for the remaining water quality indicators was still farmland. This study showed that the rational planning of land use types within 3 000 m of rivers or lakes was beneficial to improving the water quality of surface water.

17.
Cancer Immunol Immunother ; 73(4): 73, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430256

RESUMO

BACKGROUND: Cervical cancer is a common malignant tumor in the female. Interleukin (IL)-17A is a proinflammatory factor and exerts a vital function in inflammatory diseases and cancers. M2 macrophage has been confirmed to promote tumor development. Nevertheless, it is not yet known whether IL-17A facilitates cervical cancer development by inducing M2 macrophage polarization. Therefore, this study was conducted to investigate the regulatory effect of IL-17A on M2 macrophage polarization and the underlying mechanism in cervical cancer development. METHODS: RT-qPCR was utilized for testing IL-17A expression in cancer tissues and cells. Flow cytometry was applied to evaluate the M1 or M2 macrophage polarization. Cell proliferative, migratory, and invasive capabilities were measured through colony formation and transwell assays. ChIP and luciferase reporter assays were applied to determine the interaction between IL-17A and octamer-binding transcription factor 4 (OCT4). RESULTS: IL-17A expression and concentration were high in metastatic tissues and cells of cervical cancer. IL-17A was found to facilitate M2 macrophage polarization in cervical cancer. Furthermore, IL-17A facilitated the macrophage-mediated promotion of cervical cancer cell proliferative, migratory, and invasive capabilities. Mechanistic assays manifested that Oct4 binds to and transcriptionally activated IL-17A in cervical cancer cells. Furthermore, Oct4 promoted cervical cancer cell malignant phenotype and M2 macrophage polarization by activating the p38 pathway that, in turn, upregulated IL-17A. Additionally, in vivo experiments confirmed that Oct4 knockdown reduced tumor growth and metastasis. CONCLUSION: Oct4 triggers IL-17A to facilitate the polarization of M2 macrophages, which promotes cervical cancer cell metastasis.


Assuntos
Fator 3 de Transcrição de Octâmero , Neoplasias do Colo do Útero , Feminino , Humanos , Interleucina-17/metabolismo , Macrófagos/metabolismo , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Fator 3 de Transcrição de Octâmero/metabolismo
18.
J Hazard Mater ; 469: 133881, 2024 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-38422740

RESUMO

Bromine (Br) is widely distributed through the lithosphere and hydrosphere, and its chemistry in the environment is affected by natural processes and anthropogenic activities. While the chemistry of Br in the atmosphere has been comprehensively explored, there has never been an overview of the chemistry of Br in soil and aquatic systems. This review synthesizes current knowledge on the sources, geochemistry, health and environmental threats, remediation approaches, and regulatory guidelines pertaining to Br pollution in terrestrial and aquatic environments. Volcanic eruptions, geothermal streams, and seawater are the major natural sources of Br. In soils and sediments, Br undergoes natural cycling between organic and inorganic forms, with bromination reactions occurring both abiotically and through microbial activity. For organisms, Br is a non-essential element; it is passively taken up by plant roots in the form of the Br- anion. Elevated Br- levels can limit plant growth on coastal soils of arid and semi-arid environments. Br is used in the chemical industry to manufacture pesticides, flame retardants, pharmaceuticals, and other products. Anthropogenic sources of organobromine contaminants in the environment are primarily wastewater treatment, fumigants, and flame retardants. When aqueous Br- reacts with oxidants in water treatment plants, it can generate brominated disinfection by-products (DBPs), and exposure to DBPs is linked to adverse human health effects including increased cancer risk. Br- can be removed from aquatic systems using adsorbents, and amelioration of soils containing excess Br- can be achieved by leaching, adding various amendments, or phytoremediation. Developing cost-effective methods for Br- removal from wastewater would help address the problem of toxic brominated DBPs. Other anthropogenic organobromines, such as polybrominated diphenyl ether (PBDE) flame retardants, are persistent, toxic, and bioaccumulative, posing a challenge in environmental remediation. Future research directives for managing Br pollution sustainably in various environmental settings are suggested here.


Assuntos
Ecossistema , Retardadores de Chama , Humanos , Bromo , Retardadores de Chama/análise , Gestão de Riscos , Solo/química
20.
Plants (Basel) ; 13(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38337905

RESUMO

Hydroponic lettuce was prone to pest and disease problems after transplantation. Manual identification of the current growth status of each hydroponic lettuce not only consumed time and was prone to errors but also failed to meet the requirements of high-quality and efficient lettuce cultivation. In response to this issue, this paper proposed a method called YOLO-EfficientNet for identifying the growth status of hydroponic lettuce. Firstly, the video data of hydroponic lettuce were processed to obtain individual frame images. And 2240 images were selected from these frames as the image dataset A. Secondly, the YOLO-v8n object detection model was trained using image dataset A to detect the position of each hydroponic lettuce in the video data. After selecting the targets based on the predicted bounding boxes, 12,000 individual lettuce images were obtained by cropping, which served as image dataset B. Finally, the EfficientNet-v2s object classification model was trained using image dataset B to identify three growth statuses (Healthy, Diseases, and Pests) of hydroponic lettuce. The results showed that, after training image dataset A using the YOLO-v8n model, the accuracy and recall were consistently around 99%. After training image dataset B using the EfficientNet-v2s model, it achieved excellent scores of 95.78 for Val-acc, 94.68 for Test-acc, 96.02 for Recall, 96.32 for Precision, and 96.18 for F1-score. Thus, the method proposed in this paper had potential in the agricultural application of identifying and classifying the growth status in hydroponic lettuce.

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