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1.
J Clin Invest ; 134(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557493

RESUMO

Metabolic dysfunction-associated steatohepatitis (MASH) - previously described as nonalcoholic steatohepatitis (NASH) - is a major driver of liver fibrosis in humans, while liver fibrosis is a key determinant of all-cause mortality in liver disease independent of MASH occurrence. CCAAT/enhancer binding protein α (CEBPA), as a versatile ligand-independent transcriptional factor, has an important function in myeloid cells, and is under clinical evaluation for cancer therapy. CEBPA is also expressed in hepatocytes and regulates glucolipid homeostasis; however, the role of hepatocyte-specific CEBPA in modulating liver fibrosis progression is largely unknown. Here, hepatic CEBPA expression was found to be decreased during MASH progression both in humans and mice, and hepatic CEBPA mRNA was negatively correlated with MASH fibrosis in the human liver. CebpaΔHep mice had markedly enhanced liver fibrosis induced by a high-fat, high-cholesterol, high-fructose diet or carbon tetrachloride. Temporal and spatial hepatocyte-specific CEBPA loss at the progressive stage of MASH in CebpaΔHep,ERT2 mice functionally promoted liver fibrosis. Mechanistically, hepatocyte CEBPA directly repressed Spp1 transactivation to reduce the secretion of osteopontin, a fibrogenesis inducer of hepatic stellate cells. Forced hepatocyte-specific CEBPA expression reduced MASH-associated liver fibrosis. These results demonstrate an important role for hepatocyte-specific CEBPA in liver fibrosis progression, and may help guide the therapeutic discoveries targeting hepatocyte CEBPA for the treatment of liver fibrosis.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT , Hepatopatia Gordurosa não Alcoólica , Humanos , Camundongos , Animais , Hepatócitos/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Modelos Animais de Doenças
2.
Cardiovasc Diabetol ; 23(1): 128, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622690

RESUMO

BACKGROUND: Compelling evidence suggests that calcium/phosphorus homeostasis-related parameters may be linked to diabetes mellitus and cardiovascular events. However, few studies have investigated the association of fibroblast growth factor 23 (FGF23), α-klotho and FGF23/α-klotho ratio with atherosclerosis in patients with type 2 diabetes mellitus (T2DM). OBJECTIVE: This study was designed to evaluate whether FGF23, α-klotho and FGF23/α-klotho ratio are associated with T2DM and further to explore the relationships between these three factors and atherosclerosis in Chinese patients with T2DM. METHODS: Serum FGF23 and α-klotho levels were measured via an enzyme-linked immunosorbent assay (ELISA) kit, and the carotid intima-media thickness (CIMT) was assessed via high-resolution color Doppler ultrasonography. The associations of serum FGF23, α-klotho and FGF23/α-klotho ratio with atherosclerosis in T2DM patients were evaluated using multivariable logistic regression models. RESULTS: This cross-sectional study involved 403 subjects (207 with T2DM and 196 without T2DM), 41.7% of the patients had atherosclerosis, and 67.2% of the carotid intima were thickened to a thickness greater than 0.9 mm. Compared with those in the lowest tertile, higher tertiles of FGF23 levels and FGF23/α-klotho ratio were positively associated with T2DM after adjusting for covariates, and serum α-klotho concentration was inversely correlated with T2DM (all P values < 0.01). Moreover, elevated serum FGF23 levels and FGF23/α-klotho ratio were positively associated with CIMT and carotid atherosclerosis in T2DM patients (all P values < 0.01). Further spline analysis similarly revealed linear dose‒response relationship (all P values < 0.01). And there was still significant differences in CIMT and carotid atherosclerosis between the highest group of α-klotho and the reference group in T2DM patients (P values = 0.05). CONCLUSIONS: T2DM was positively linearly related to serum FGF23 concentration and FGF23/α-klotho ratio, and negatively correlated with serum α-klotho concentration. Furthermore, both FGF23 and FGF23/α-klotho ratio were positively correlated with CIMT and atherosclerosis in T2DM patients, while α-klotho was inversely correlated with both CIMT and atherosclerosis, although the associations were not completely significant. Prospective exploration and potential mechanisms underlying these associations remain to be further elucidated.


Assuntos
Aterosclerose , Doenças das Artérias Carótidas , Diabetes Mellitus Tipo 2 , Humanos , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/etiologia , Espessura Intima-Media Carotídea , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Estudos Prospectivos , Fatores de Risco
3.
J Am Chem Soc ; 146(15): 10257-10262, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38578111

RESUMO

Sorption-based atmospheric water harvesting (AWH) is a promising solution for addressing water scarcity. Developing cost-effective and stable water adsorbents with high water uptake capacity and a low-temperature regeneration requirement is a crucially important procedure. In this Communication, we present a novel and stable aluminophosphate (AlPO) molecular sieve (MS) named DNL-11 with 16-ring channels synthesized by using an affordable and commercialized organic structure directing agent (OSDA), whose crystallographic structure is elucidated by three-dimensional electron diffraction (3D ED). DNL-11 exhibits a significant water uptake capacity (189 mg/g) at a very low vapor pressure (5% relative humidity at 30 °C). In addition, most of the adsorbed water can be effortlessly removed by purging N2 at 25 °C under ambient pressure conditions. This may expand the possibility of AWH under extreme drought conditions.

4.
Int J Biol Macromol ; 268(Pt 2): 131785, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38679258

RESUMO

To expand the scope of genomic editing, a C-to-G transversion-based editor called CGBE has been developed for precise single-nucleotide genomic editing. However, limited editing efficiency and product purity have hindered the development and application of CGBE. In this study, we introduced the Puromycin-Resistance Screening System, referred to as CGBE/ABE-PRSS, to select genetically modified cells via the CGBE or ABE editors. The CGBE/ABE-PRSS system significantly improves the enrichment efficiency of CGBE- or ABE-modified cells, showing enhancements of up to 59.6 % compared with the controls. Our findings indicate that the CGBE/ABE-PRSS, when driven by the CMV promoter, results in a higher enrichment of edited cells compared to the CAG and EF1α promoters. Furthermore, we demonstrate that this system is compatible with different versions of both CGBE and ABE, enabling various cell species and simultaneous multiplexed genome editing without any detectable random off-targets. In conclusion, our developed CGBE/ABE-PRSS system facilitates the selection of edited cells and holds promise in both basic engineering and gene therapy applications.


Assuntos
Resistência Microbiana a Medicamentos , Edição de Genes , Edição de Genes/métodos , Humanos , Resistência Microbiana a Medicamentos/genética , Sistemas CRISPR-Cas , Células HEK293 , Regiões Promotoras Genéticas , Puromicina/farmacologia , Animais
5.
Structure ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38521071

RESUMO

Membrane forces shift the equilibria of mechanosensitive channels enabling them to convert mechanical cues into electrical signals. Molecular tools to stabilize and methods to capture their highly dynamic states are lacking. Cyclodextrins can mimic tension through the sequestering of lipids from membranes. Here we probe the conformational ensemble of MscS by EPR spectroscopy, the lipid environment with NMR, and function with electrophysiology under cyclodextrin-induced tension. We show the extent of MscS activation depends on the cyclodextrin-to-lipid ratio, and that lipids are depleted slower when MscS is present. This has implications in MscS' activation kinetics when distinct membrane scaffolds such as nanodiscs or liposomes are used. We find MscS transits from closed to sub-conducting state(s) before it desensitizes, due to the lack of lipid availability in its vicinity required for closure. Our approach allows for monitoring tension-sensitive states in membrane proteins and screening molecules capable of inducing molecular tension in bilayers.

6.
Cell Discov ; 10(1): 20, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378648

RESUMO

Adenine base editors (ABEs) and cytosine base editors (CBEs) enable the single nucleotide editing of targeted DNA sites avoiding generation of double strand breaks, however, the genomic features that influence the outcomes of base editing in vivo still remain to be characterized. High-throughput datasets from lentiviral integrated libraries were used to investigate the sequence features affecting base editing outcomes, but the effects of endogenous factors beyond the DNA sequences are still largely unknown. Here the base editing outcomes of ABE and CBE were evaluated in mammalian cells for 5012 endogenous genomic sites and 11,868 genome-integrated target sequences, with 4654 genomic sites sharing the same target sequences. The comparative analyses revealed that the editing outcomes of ABE and CBE at endogenous sites were substantially different from those obtained using genome-integrated sequences. We found that the base editing efficiency at endogenous target sites of both ABE and CBE was influenced by endogenous factors, including epigenetic modifications and transcriptional activity. A deep-learning algorithm referred as BE_Endo, was developed based on the endogenous factors and sequence information from our genomic datasets, and it yielded unprecedented accuracy in predicting the base editing outcomes. These findings along with the developed computational algorithms may facilitate future application of BEs for scientific research and clinical gene therapy.

7.
Genome Biol ; 25(1): 51, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378658

RESUMO

The FokI catalytic domain can be fused to various DNA binding architectures to improve the precision of genome editing tools. However, evaluation of off-target effects is essential for developing these tools. We use Genome-wide Off-target analysis by Two-cell embryo Injection (GOTI) to detect low-frequency off-target editing events in mouse embryos injected with FokI-based architectures. Specifically, we test FokI-heterodimers fused with TALENs, FokI homodimers fused with RYdCas9, or FokI catalytic domains alone resulting in no significant off-target effects. These FokI genome editing systems exhibit undetectable off-target effects in mouse embryos, supporting the further development of these systems for clinical applications.


Assuntos
Edição de Genes , Genoma , Animais , Camundongos , Domínio Catalítico , Edição de Genes/métodos , Sistemas CRISPR-Cas
8.
J Am Chem Soc ; 145(44): 24191-24201, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37877469

RESUMO

The pure-silica zeolite plays a crucially important role in the gas separation of alkane/alkene, the low-k dielectric material, and the robust matrix for confining metal species during catalysis. However, the environmentally friendly synthesis of pure-silica zeolites is still challenging since (1) the toxic fluoride or dealuminum seeds are inevitably utilized through the hydrothermal synthesis and (2) it will also take a longer crystallization time. Herein, we present an efficient method called the OSDA-mismatch approach for the fluoride- and seed-free synthesis of pure-silica zeolites using Si-SOD (enriched 4-rings) as the sole silica source. This approach allows for the rapid and green synthesis of 15 pure-silica zeolites (CHA, *BEA, EUO, SFF, STF, -SVR, *-SVY, DOH, MTN, NON, *MRE, MEL, MFI, MTW, and *STO). Furthermore, distinct crystallization mechanisms of two significant pure-silica CHA- and *BEA-type zeolites (denoted as Si-CHA and Si-BEA) are investigated in detail by advanced characterization techniques such as FIB, 3D ED, 4D-STEM, HRTEM, Raman, and 29Si MAS NMR. More importantly, Si-CHA displays promising propane/propylene separation performance even better than the one synthesized in the presence of toxic HF. In addition, the incorporation of Zn species within Si-BEA fabricated by this approach also renders superior performance on propane dehydrogenation.

9.
J Microbiol Methods ; 215: 106848, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37871727

RESUMO

Metagenomic next-generation sequencing (mNGS) is widely used as a more promising technology than conventional tests. However, its clinical utility in the context of bronchoalveolar lavage fluid (BALF) samples for discriminating between non-severe and severe pneumonia is not well established. Thus, this study aimed to investigate the diagnostic performance of mNGS on BALF samples from 100 individuals suspected of pneumonia, and compared it with conventional microbiological tests (CMT) of BALF samples and the final clinical diagnosis. Twenty-seven cases of non-severe pneumonia and 73 cases of severe pneumonia patients were finally clinically diagnosed. Among 100 cases, diagnostic performance of mNGS and culture showed a significant difference; 65 cases had the same sample types, of which 25 cases were diagnosed as positive by mNGS only (38.46%) and 1 was diagnosed as positive by culture only (1.54%). Moreover, 24 cases were diagnosed positive in both mNGS and culture (36.92%) and 15 cases tested negative in both mNGS and culture (23.08%). Among 35 cases, 28 out of 35 cases were diagnosed as positive by mNGS, while only 4 out of 35 cases were diagnosed as positive by the indirect immunofluorescence method (IIFT). In addition, the positive rate of mNGS was higher than that of culture in cases regardless of prior antibiotic exposure. Mixed pathogens were found to be significantly more prevalent in severe pneumonia patients than in non-severe pneumonia patients. Importantly, among 38 cases who were diagnosed solely by mNGS, 25 patients experienced an improved outcome after physicians changed the therapy according to the mNGS results. In conclusion, the results showed that mNGS of BALF represents a potentially effective tool for detection of mixed pathogens in severe pneumonia.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Pneumonia , Humanos , Líquido da Lavagem Broncoalveolar , Antibacterianos , Metagenoma , Metagenômica , Pneumonia/diagnóstico , Sensibilidade e Especificidade
10.
Nat Commun ; 14(1): 4189, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37443163

RESUMO

Separating deuterium from hydrogen isotope mixtures is of vital importance to develop nuclear energy industry, as well as other isotope-related advanced technologies. As one of the most promising alternatives to conventional techniques for deuterium purification, kinetic quantum sieving using porous materials has shown a great potential to address this challenging objective. From the knowledge gained in this field; it becomes clear that a quantum sieve encompassing a wide range of practical features in addition to its separation performance is highly demanded to approach the industrial level. Here, the rational design of an ultra-microporous squarate pillared titanium oxide hybrid framework has been achieved, of which we report the comprehensive assessment towards practical deuterium separation. The material not only displays a good performance combining high selectivity and volumetric uptake, reversible adsorption-desorption cycles, and facile regeneration in adsorptive sieving of deuterium, but also features a cost-effective green scalable synthesis using chemical feedstock, and a good stability (thermal, chemical, mechanical and radiolytic) under various working conditions. Our findings provide an overall assessment of the material for hydrogen isotope purification and the results represent a step forward towards next generation practical materials for quantum sieving of important gas isotopes.


Assuntos
Hidrogênio , Deutério , Adsorção , Transporte Biológico
11.
Int J Biol Macromol ; 243: 124926, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37217056

RESUMO

CRISPR/Cas9 is a powerful tool for gene editing in various cell types and organisms. However, it is still challenging to screen genetically modified cells from an excess of unmodified cells. Our previous studies demonstrated that surrogate reporters can be used for efficient screening of genetically modified cells. Here, we developed two novel traffic light screening reporters, puromycin-mCherry-EGFP (PMG) based on single-strand annealing (SSA) and homology-directed repair (HDR), respectively, to measure the nuclease cleavage activity within transfected cells and to select genetically modified cells. We found that the two reporters could be self-repaired coupling the genome editing events driven by different CRISPR/Cas nucleases, resulting in a functional puromycin-resistance and EGFP selection cassette that can be afforded to screen genetically modified cells by puromycin selection or FACS enrichment. We further compared the novel reporters with different traditional reporters at several endogenous loci in different cell lines, for the enrichment efficiencies of genetically modified cells. The results indicated that the SSA-PMG reporter exhibited improvements in enriching gene knockout cells, while the HDR-PMG system was very useful in enriching knock-in cells. These results provide robust and efficient surrogate reporters for the enrichment of CRISPR/Cas9-mediated editing in mammalian cells, thereby advancing basic and applied research.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Animais , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Linhagem Celular , Técnicas de Inativação de Genes , Puromicina/farmacologia , Mamíferos
12.
Clin Oral Investig ; 27(7): 3885-3894, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37017752

RESUMO

OBJECTIVES: To investigate the genetic causes and teeth characteristics of dentin dysplasia Shields type II(DD-II) in three Chinese families. MATERIALS AND METHODS: Data from three Chinese families affected with DD-II were collected. Whole-exome sequencing (WES) and whole-genome sequencing (WGS) were conducted to screen for variations, and Sanger sequencing was used to verify mutation sites. The physical and chemical characteristics of the affected teeth including tooth structure, hardness, mineral content, and ultrastructure were investigated. RESULTS: A novel frameshift deletion mutation c.1871_1874del(p.Ser624fs) in DSPP was found in families A and B, while no pathogenic mutation was found in family C. The affected teeth's pulp cavities were obliterated, and the root canals were smaller than normal teeth and irregularly distributed comprising a network. The patients' teeth also had reduced dentin hardness and highly irregular dentinal tubules. The Mg content of the teeth was significantly lower than that of the controls, but the Na content was obviously higher than that of the controls. CONCLUSIONS: A novel frameshift deletion mutation, c.1871_1874del (p.Ser624fs), in the DPP region of the DSPP gene causes DD-II. The DD-II teeth demonstrated compromised mechanical properties and changed ultrastructure, suggesting an impaired function of DPP. Our findings expand the mutational spectrum of the DSPP gene and strengthen the understanding of clinical phenotypes related to the frameshift deletion in the DPP region of the DSPP gene. CLINICAL RELEVANCE: A DSPP mutation can alter the characteristics of the affected teeth, including tooth structure, hardness, mineral content, and ultrastructure.


Assuntos
Dentinogênese Imperfeita , Dente , Humanos , Dentina/patologia , Dentinogênese , Dentinogênese Imperfeita/genética , Proteínas da Matriz Extracelular/genética , Mutação , Fenótipo
13.
Natl Sci Rev ; 10(4): nwac290, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36960224

RESUMO

Building a more resilient food system for sustainable development and reducing uncertainty in global food markets both require concurrent and near-real-time and reliable crop information for decision making. Satellite-driven crop monitoring has become a main method to derive crop information at local, regional, and global scales by revealing the spatial and temporal dimensions of crop growth status and production. However, there is a lack of quantitative, objective, and robust methods to ensure the reliability of crop information, which reduces the applicability of crop monitoring and leads to uncertain and undesirable consequences. In this paper, we review recent progress in crop monitoring and identify the challenges and opportunities in future efforts. We find that satellite-derived metrics do not fully capture determinants of crop production and do not quantitatively interpret crop growth status; the latter can be advanced by integrating effective satellite-derived metrics and new onboard sensors. We have identified that ground data accessibility and the negative effects of knowledge-based analyses are two essential issues in crop monitoring that reduce the applicability of crop monitoring for decisions on food security. Crowdsourcing is one solution to overcome the restrictions of ground-truth data accessibility. We argue that user participation in the complete process of crop monitoring could improve the reliability of crop information. Encouraging users to obtain crop information from multiple sources could prevent unconscious biases. Finally, there is a need to avoid conflicts of interest in publishing publicly available crop information.

14.
Nat Commun ; 14(1): 1784, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36997536

RESUMO

Base editors have been reported to induce off-target mutations in cultured cells, mouse embryos and rice, but their long-term effects in vivo remain unknown. Here, we develop a Systematic evaluation Approach For gene Editing tools by Transgenic mIce (SAFETI), and evaluate the off-target effects of BE3, high fidelity version of CBE (YE1-BE3-FNLS) and ABE (ABE7.10F148A) in ~400 transgenic mice over 15 months. Whole-genome sequence analysis reveals BE3 expression generated de novo mutations in the offspring of transgenic mice. RNA-seq analysis reveals both BE3 and YE1-BE3-FNLS induce transcriptome-wide SNVs, and the numbers of RNA SNVs are positively correlated with CBE expression levels across various tissues. By contrast, ABE7.10F148A shows no detectable off-target DNA or RNA SNVs. Notably, we observe abnormal phenotypes including obesity and developmental delay in mice with permanent genomic BE3 overexpression during long-time monitoring, elucidating a potentially overlooked aspect of side effects of BE3 in vivo.


Assuntos
Citosina , Edição de Genes , Animais , Camundongos , Camundongos Transgênicos , Citosina/metabolismo , Mutação , Edição de Genes/métodos , RNA/genética , Sistemas CRISPR-Cas
15.
Hepatology ; 77(1): 239-255, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35460276

RESUMO

BACKGROUND AND AIMS: Peroxisome proliferator-activated receptor α (PPARα) regulates fatty acid transport and catabolism in liver. However, the role of intestinal PPARα in lipid homeostasis is largely unknown. Here, intestinal PPARα was examined for its modulation of obesity and NASH. APPROACH AND RESULTS: Intestinal PPARα was activated and fatty acid-binding protein 1 (FABP1) up-regulated in humans with obesity and high-fat diet (HFD)-fed mice as revealed by using human intestine specimens or HFD/high-fat, high-cholesterol, and high-fructose diet (HFCFD)-fed C57BL/6N mice and PPARA -humanized, peroxisome proliferator response element-luciferase mice. Intestine-specific Ppara or Fabp1 disruption in mice fed a HFD or HFCFD decreased obesity-associated metabolic disorders and NASH. Molecular analyses by luciferase reporter assays and chromatin immunoprecipitation assays in combination with fatty acid uptake assays in primary intestinal organoids revealed that intestinal PPARα induced the expression of FABP1 that in turn mediated the effects of intestinal PPARα in modulating fatty acid uptake. The PPARα antagonist GW6471 improved obesity and NASH, dependent on intestinal PPARα or FABP1. Double-knockout ( Ppara/Fabp1ΔIE ) mice demonstrated that intestinal Ppara disruption failed to further decrease obesity and NASH in the absence of intestinal FABP1. Translationally, GW6471 reduced human PPARA-driven intestinal fatty acid uptake and improved obesity-related metabolic dysfunctions in PPARA -humanized, but not Ppara -null, mice. CONCLUSIONS: Intestinal PPARα signaling promotes NASH progression through regulating dietary fatty acid uptake through modulation of FABP1, which provides a compelling therapeutic target for NASH treatment.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR alfa/metabolismo , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Dieta Hiperlipídica/efeitos adversos , Obesidade/metabolismo , Camundongos Knockout , Intestinos , Proteínas de Ligação a Ácido Graxo/metabolismo , Proteínas de Ligação a Ácido Graxo/farmacologia , Ácidos Graxos/metabolismo
16.
Channels (Austin) ; 16(1): 148-158, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35941834

RESUMO

Mechanosensitive ion channels are integral membrane proteins ubiquitously present in bacteria, archaea, and eukarya. They act as molecular sensors of mechanical stress to serve vital functions such as touch, hearing, osmotic pressure, proprioception and balance, while their malfunction is often associated with pathologies. Amongst them, the structurally distinct MscL and MscS channels from bacteria are the most extensively studied. MscS-like channels have been found in plants and Schizosaccharomyces pombe, where they regulate intracellular Ca2+ and cell volume under hypo-osmotic conditions. Here we characterize two MscS-like putative channels, named MscA and MscB, from the model filamentous fungus Aspergillus nidulans. Orthologues of MscA and MscB are present in most fungi, including relative plant and animal pathogens. MscA/MscB and other fungal MscS-like proteins share the three transmembrane helices and the extended C-terminal cytosolic domain that form the structural fingerprint of MscS-like channels with at least three additional transmembrane segments than Escherichia coli MscS. We show that MscA and MscB localize in Endoplasmic Reticulum and the Plasma Membrane, respectively, whereas their overexpression leads to increased CaCl2 toxicity or/and reduction of asexual spore formation. Our findings contribute to understanding the role of MscS-like channels in filamentous fungi and relative pathogens.


Assuntos
Aspergillus nidulans , Proteínas de Escherichia coli , Aspergillus nidulans/genética , Aspergillus nidulans/metabolismo , Bactérias/metabolismo , Escherichia coli , Proteínas de Escherichia coli/metabolismo , Canais Iônicos/metabolismo , Mecanotransdução Celular , Pressão Osmótica/fisiologia
17.
Viruses ; 14(7)2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35891504

RESUMO

Infectious bursal disease virus (IBDV) is one of the main threats to the poultry industry worldwide. Very virulent IBDV (vvIBDV) is a fatal virus strain that causes heavy mortality in young chicken flocks. Ca2+ is one of the most universal and versatile signalling molecules and is involved in almost every aspect of cellular processes. Clinical examination showed that one of the characteristics of vvIBDV-infected chickens was severe metabolic disorders, and the chemical examination showed that their serum Ca2+ level decreased significantly. However, there are limited studies on how vvIBDV infection modulates the cellular Ca2+ level and the effect of Ca2+ level changes on vvIBDV replication. In our study, we found Ca2+ levels in the endoplasmic reticulum (ER) of vvIBDV-infected B cells were higher than that of mock-infected cells, and the expression level of stromal interaction molecule 1 (STIM1), an ER Ca2+ sensor, was significantly upregulated due to vvIBDV infection. The knock-down expression of STIM1 led to decreased Ca2+ level in the ER and suppressed vvIBDV replication, while the over-expressed STIM1 led to ER Ca2+ upregulation and promoted vvIBDV replication. We also showed that the inhibition of Ca2+-release-activated-Ca2+ (CRAC) channels could reduce vvIBDV infection by blocking Ca2+ from entering the ER. This study suggests a new mechanism that STIM1 promotes the replication of vvIBDV by mobilizing Ca2+ in the ER.


Assuntos
Infecções por Birnaviridae , Vírus da Doença Infecciosa da Bursa , Doenças das Aves Domésticas , Animais , Infecções por Birnaviridae/veterinária , Galinhas , Retículo Endoplasmático , Molécula 1 de Interação Estromal/genética
18.
Molecules ; 27(4)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35209218

RESUMO

BACKGROUND: This study aimed to develop an ultrathin nanofibrous membrane able to, firstly, mimic the natural fibrous architecture of human Bruch's membrane (BM) and, secondly, promote survival of retinal pigment epithelial (RPE) cells after surface functionalization of fibrous membranes. METHODS: Integrin-binding peptides (IBPs) that specifically interact with appropriate adhesion receptors on RPEs were immobilized on Bruch's-mimetic membranes to promote coverage of RPEs. Surface morphologies, Fourier-transform infrared spectroscopy spectra, contact angle analysis, Alamar Blue assay, live/dead assay, immunofluorescence staining, and scanning electron microscopy were used to evaluate the outcome. RESULTS: Results showed that coated membranes maintained the original morphology of nanofibers. After coating with IBPs, the water contact angle of the membrane surfaces varied from 92.38 ± 0.67 degrees to 20.16 ± 0.81 degrees. RPE cells seeded on IBP-coated membranes showed the highest viability at all time points (Day 1, p < 0.05; Day 3, p < 0.01; Days 7 and 14, p < 0.001). The proliferation rate of RPE cells on uncoated poly(ε-caprolactone) (PCL) membranes was significantly lower than that of IBP-coated membranes (p < 0.001). SEM images showed a well-organized hexa/polygonal monolayer of RPE cells on IBP-coated membranes. RPE cells proliferated rapidly, contacted, and became confluent. RPE cells formed a tight adhesion with nanofibers under high-magnification SEM. Our findings confirmed that the IBP-coated PCL membrane improved the attachment, proliferation, and viability of RPE cells. In addition, in this study, we used serum-free culture for RPE cells and short IBPs without immunogenicity to prevent graft rejection and immunogenicity during transplantation. CONCLUSIONS: These results indicated that the biomimic BM-IBP-RPE nanofibrous graft might be a new, practicable approach to increase the success rate of RPE cell transplantation.


Assuntos
Lâmina Basilar da Corioide , Nanofibras , Peptídeos , Epitélio Pigmentado da Retina/transplante , Engenharia Tecidual , Materiais Biocompatíveis , Biomimética/métodos , Adesão Celular , Transplante de Células , Células Cultivadas , Fenômenos Químicos , Humanos , Integrinas/metabolismo , Nanofibras/química , Nanofibras/ultraestrutura , Peptídeos/metabolismo , Análise Espectral
19.
Food Chem Toxicol ; 160: 112807, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34995708

RESUMO

Withaferin A (WA) is a natural steroidal compound with reported hepatoprotective activities against various liver diseases. Whether WA has therapeutic effects on alcoholic liver disease has not been explored. A binge alcoholic liver injury model was employed by feeding C57BL/6J mice an ethanol (EtOH) diet for 10 days followed by an acute dose of EtOH to mimic clinical acute-upon-chronic liver injury. In this binge model, WA significantly reduced the binge EtOH-induced increase of serum aminotransaminase levels and decreased hepatic lipid accumulation. Mechanistically, WA decreased levels of hepatic lipogenesis gene mRNAs in vivo, including Srebp1c, Fasn, Acc1 and Fabp1. In EtOH-treated primary hepatocytes in vitro, WA decreased lipid accumulation by lowering the expression of the lipogenesis gene mRNAs Fasn and Acc1 as well as decreasing hepatocyte death. In the established binge alcoholic liver injury model, WA therapeutically reduced the EtOH-induced increase of serum aminotransaminase levels as well as hepatic lipid accumulation. These results demonstrate that WA reduces EtOH-induced liver injury by inhibiting hepatic lipogenesis, suggesting a potential therapeutic option for treating alcoholic liver injury.


Assuntos
Etanol/efeitos adversos , Lipogênese/efeitos dos fármacos , Hepatopatias Alcoólicas/tratamento farmacológico , Hepatopatias Alcoólicas/fisiopatologia , Vitanolídeos/administração & dosagem , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Feminino , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/lesões , Fígado/fisiopatologia , Hepatopatias Alcoólicas/etiologia , Hepatopatias Alcoólicas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
20.
Drug Metab Dispos ; 50(5): 685-693, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34903587

RESUMO

Withaferin A (WA) is a natural steroidal compound used in Ayurvedic medicine in India and elsewhere. Although WA was used as an anticancer reagent for decades, its role in the treatment of liver diseases has only recently been experimentally explored. Here, the effects of WA in the treatment of liver injury, systematic inflammation, and liver cancer are reviewed, and the toxicity and metabolism of WA as well as pharmacological potentials of other extracts from Withania somnifera (W. somnifera) discussed. The pharmacokinetic behaviors of WA are summarized and pharmacokinetic insights into current progress and future opportunities are highlighted. SIGNIFICANCE STATEMENT: This review outlines the current experimental progress of Withaferin A (WA) hepatoprotective activities and highlights gaps in the field. This work also discusses the pharmacokinetics of WA that can be used to guide future studies for the possible treatment of liver diseases with this compound.


Assuntos
Hepatopatias , Withania , Vitanolídeos , Humanos , Hepatopatias/tratamento farmacológico , Ayurveda , Vitanolídeos/farmacocinética , Vitanolídeos/uso terapêutico
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