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1.
J Biol Chem ; 300(3): 105661, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246352

RESUMO

Nonalcoholic fatty liver disease (NAFLD), especially nonalcoholic steatohepatitis (NASH), has emerged as a prevalent cause of liver cirrhosis and hepatocellular carcinoma, posing severe public health challenges worldwide. The incidence of NASH is highly correlated with an increased prevalence of obesity, insulin resistance, diabetes, and other metabolic diseases. Currently, no approved drugs specifically targeted for the therapies of NASH partially due to the unclear pathophysiological mechanisms. G protein-coupled estrogen receptor 1 (GPER1) is a membrane estrogen receptor involved in the development of metabolic diseases such as obesity and diabetes. However, the function of GPER1 in NAFLD/NASH progression remains unknown. Here, we show that GPER1 exerts a beneficial role in insulin resistance, hepatic lipid accumulation, oxidative stress, or inflammation in vivo and in vitro. In particular, we observed that the lipid accumulation, inflammatory response, fibrosis, or insulin resistance in mouse NAFLD/NASH models were exacerbated by hepatocyte-specific GPER1 knockout but obviously mitigated by hepatic GPER1 activation in female and male mice. Mechanistically, hepatic GPER1 activates AMP-activated protein kinase signaling by inducing cyclic AMP release, thereby exerting its protective effect. These data suggest that GPER1 may be a promising therapeutic target for NASH.


Assuntos
Diabetes Mellitus , Resistência à Insulina , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Animais , Feminino , Masculino , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Diabetes Mellitus/metabolismo , Modelos Animais de Doenças , Receptor alfa de Estrogênio/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Lipídeos/farmacologia , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Camundongos Endogâmicos C57BL , Estrogênios/deficiência , Estrogênios/metabolismo , Dieta Hiperlipídica
2.
Stroke ; 55(5): 1261-1270, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38511332

RESUMO

BACKGROUND: Mitochondrial DNA copy number (mtDNA-CN) is associated with the severity and mortality in patients with stroke, but the associations in different stroke subtypes remain unexplored. METHODS: We conducted an observational prospective cohort analysis on patients with ischemic stroke or transient ischemic attack enrolled in the Third China National Stroke Registry. We applied logistic models to assess the association of mtDNA-CN with functional outcome (modified Rankin Scale score, 3-6 versus 0-2) and Cox proportional hazard models to assess the association with stroke recurrence (treating mortality as a competing risk) and mortality during a 12-month follow-up, adjusting for sex, age, physical activity, National Institutes of Health Stroke Scale at admission, history of stroke and peripheral artery disease, small artery occlusion, and interleukin-6. Subgroup analyses stratified by age and stroke subtypes were conducted. RESULTS: The Third China National Stroke Registry enrolled 15 166 patients, of which 10 241 with whole-genome sequencing data were retained (mean age, 62.2 [SD, 11.2] years; 68.8% men). The associations between mtDNA-CN and poststroke/transient ischemic attack outcomes were specific to patients aged ≤65 years, with lower mtDNA-CN significantly associated with stroke recurrence in 12 months (subdistribution hazard ratio, 1.15 per SD lower mtDNA-CN [95% CI, 1.04-1.27]; P=5.2×10-3) and higher all-cause mortality in 3 months (hazard ratio, 2.19 [95% CI, 1.41-3.39]; P=5.0×10-4). Across subtypes, the associations of mtDNA-CN with stroke recurrence were specific to stroke of undetermined cause (subdistribution hazard ratio, 1.28 [95% CI, 1.11-1.48]; P=6.6×10-4). In particular, lower mtDNA-CN was associated with poorer functional outcomes in stroke of undetermined cause patients diagnosed with embolic stroke of undetermined source (odds ratio, 1.53 [95% CI, 1.20-1.94]; P=5.4×10-4), which remained significant after excluding patients with recurrent stroke (odds ratio, 1.49 [95% CI, 1.14-1.94]; P=3.0×10-3). CONCLUSIONS: Lower mtDNA-CN is associated with higher stroke recurrence rate and all-cause mortality, as well as poorer functional outcome at follow-up, among stroke of undetermined cause, embolic stroke of undetermined source, and younger patients.

3.
BMC Genomics ; 25(1): 363, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609871

RESUMO

BACKGROUND: Cold hardiness is fundamental for amphibians to survive during the extremely cold winter on the Qinghai-Tibet plateau. Exploring the gene regulation mechanism of freezing-tolerant Rana kukunoris could help us to understand how the frogs survive in winter. RESULTS: Transcriptome of liver and muscle of R. kukunoris collected in hibernation and spring were assisted by single molecule real-time (SMRT) sequencing technology. A total of 10,062 unigenes of R. kukunoris were obtained, and 9,924 coding sequences (CDS) were successfully annotated. Our examination of the mRNA response to whole body freezing and recover in the frogs revealed key genes concerning underlying antifreeze proteins and cryoprotectants (glucose and urea). Functional pathway analyses revealed differential regulated pathways of ribosome, energy supply, and protein metabolism which displayed a freeze-induced response and damage recover. Genes related to energy supply in the muscle of winter frogs were up-regulated compared with the muscle of spring frogs. The liver of hibernating frogs maintained modest levels of protein synthesis in the winter. In contrast, the liver underwent intensive high levels of protein synthesis and lipid catabolism to produce substantial quantity of fresh proteins and energy in spring. Differences between hibernation and spring were smaller than that between tissues, yet the physiological traits of hibernation were nevertheless passed down to active state in spring. CONCLUSIONS: Based on our comparative transcriptomic analyses, we revealed the likely adaptive mechanisms of R. kukunoris. Ultimately, our study expands genetic resources for the freezing-tolerant frogs.


Assuntos
Resposta ao Choque Frio , Transcriptoma , Animais , Resposta ao Choque Frio/genética , Tibet , Perfilação da Expressão Gênica , Ranidae/genética , Anuros
4.
Plant Mol Biol ; 114(5): 101, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39312030

RESUMO

Histone deacetylation, one of most important types of post-translational modification, plays multiple indispensable roles in plant growth and development and abiotic stress responses. However, little information about the roles of histone deacetylase in regulating inflorescence architecture, fruit yield, and stress responses is available in tomato. Functional characterization revealed that SlHDT1 participated in the control of inflorescence architecture and fruit yield by regulating auxin signalling, and influenced tolerance to drought and salt stresses by governing abscisic acid (ABA) signalling. More inflorescence branches and higher fruit yield, which were influenced by auxin signalling, were observed in SlHDT1-RNAi transgenic plants. Moreover, tolerance to drought and salt stresses was decreased in SlHDT1-RNAi transgenic lines compared with the wild type (WT). Changes in parameters related to the stress response, including decreases in survival rate, chlorophyll content, relative water content (RWC), proline content, catalase (CAT) activity and ABA content and an increase in malonaldehyde (MDA) content, were observed in SlHDT1-RNAi transgenic lines. In addition, the RNA-seq analysis revealed varying degrees of downregulation for genes such as the stress-related genes SlABCC10 and SlGAME6 and the pathogenesis-related protein P450 gene SlCYP71A1, and upregulation of the pathogenesis-related protein P450 genes SlCYP94B1, SlCYP734A7 and SlCYP94A2 in SlHDT1-RNAi transgenic plants, indicating that SlHDT1 plays an important role in the response to biotic and abiotic stresses by mediating stress-related gene expression. In summary, the data suggest that SlHDT1 plays essential roles in the regulation of inflorescence architecture and fruit yield and in the response to drought and salt stresses.


Assuntos
Ácido Abscísico , Secas , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Tolerância ao Sal , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/fisiologia , Solanum lycopersicum/crescimento & desenvolvimento , Tolerância ao Sal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Abscísico/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Estresse Fisiológico/genética , Ácidos Indolacéticos/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo
5.
Plant Cell Physiol ; 65(5): 781-789, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38447119

RESUMO

MicroRNAs (miRNAs) are known to play critical roles in regulating rice agronomic traits through mRNA cleavage or translational repression. Our previous study indicated that miR5504 regulates plant height by affecting cell proliferation and expansion. Here, the two independent homozygous mir5504 mutants (CR1 and CR2) and overexpression lines (OE1 and OE2) were further used to investigate the functions of miR5504. The panicle length, 1000-grain weight and grain yield per plant of miR5504-OE lines were identical to those of Nipponbare (NIP), but the 1000-grain weight of mir5504 mutants was reduced by about 10% and 9%, respectively. Meanwhile, the grain width and thickness of mir5504 mutants decreased significantly by approximately 10% and 11%, respectively. Moreover, the cytological results revealed a significant decrease in cell number along grain width direction and cell width in spikelet in mir5504, compared with those in NIP. In addition, several major storage substances of the rice seeds were measured. Compared to NIP, the amylose content of the mir5504 seeds was noticeably decreased, leading to an increase of nearly 10 mm in gel consistency (GC) in mir5504 lines. Further investigation confirmed that LOC_Os08g16914 was the genuine target of miR5504: LOC_Os08g16914 over-expression plants phenocopied the mir5504 mutants. This study provides insights into the role of miR5504 in rice seed development.


Assuntos
Grão Comestível , Regulação da Expressão Gênica de Plantas , MicroRNAs , Oryza , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Mutação , Pleiotropia Genética , Plantas Geneticamente Modificadas , RNA de Plantas/genética , RNA de Plantas/metabolismo , Amilose/metabolismo
6.
Small ; 20(4): e2304968, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37715278

RESUMO

The contrast agents and tumor treatments currently used in clinical practice are far from satisfactory, due to the specificity of the tumor microenvironment (TME). Identification of diagnostic and therapeutic reagents with strong contrast and therapeutic effect remains a great challenge. Herein, a novel carbon dot nanozyme (Mn-CD) is synthesized for the first time using toluidine blue (TB) and manganese as raw materials. As expected, the enhanced magnetic resonance (MR) imaging capability of Mn-CDs is realized in response to the TME (acidity and glutathione), and r1 and r2 relaxation rates are enhanced by 224% and 249%, respectively. In addition, the photostability of Mn-CDs is also improved, and show an efficient singlet oxygen (1 O2 ) yield of 1.68. Moreover, Mn-CDs can also perform high-efficiency peroxidase (POD)-like activity and catalyze hydrogen peroxide to hydroxyl radicals, which is greatly improved under the light condition. The results both in vitro and in vivo demonstrate that the Mn-CDs are able to achieve real-time MR imaging of TME responsiveness through aggregation of the enhanced permeability and retention effect at tumor sites and facilitate light-enhanced chemodynamic and photodynamic combination therapies. This work opens a new perspective in terms of the role of carbon nanomaterials in integrated diagnosis and treatment of diseases.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Cloreto de Tolônio , Manganês , Espécies Reativas de Oxigênio , Carbono , Peróxido de Hidrogênio , Imageamento por Ressonância Magnética , Microambiente Tumoral , Linhagem Celular Tumoral
7.
Small ; 20(30): e2311013, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38372007

RESUMO

The ability to design halide perovskite nanocrystals (PNCs) with circularly polarized luminescence (CPL) offers exceptional potential in photonic technologies. Despite recent inspiring advances, the creation of PNCs with full-color tailorablity, outstanding CPL, and long-term stability remains a substantial challenge. Herein, a robust strategy to craft CPL-active PNCs is reported, exhibiting appealing full-color tunable wavelengths, enhanced CPL, and prolonged stability. In contrast to conventional methodologies, this strategy utilizes chiral nematic mesoporous silica (CNMS) as host to render in situ confined growth of diverse achiral PNCs. By strategically engineering photonic bandgap, adjusting loading amount of PNCs, and manipulating cations/anion compositions of PNCs, robust CPL responses with tunable wavelength and intensity are successfully obtained. The resulting PNCs-CNMS achieves stable CPL emissions with full-color tunability and impressive luminescent dissymmetric factors up to -0.17. Remarkably, silica-based hosts as a protective barrier confer exceptional resistance to humidity, photodegradation, and thermal stability, even up to 95 °C. Furthermore, the ability to achieve reversible CPL switching within PNCs-CNMS is attainable by leveraging the responsiveness of CNMS matrix or dynamic behavior of impregnated PNCs. Additionally, circularly polarized light-emitting diode devices based on PNCs-CNMS can be conveniently fabricated. This research affords a powerful platform for designing functional chiroptical materials.

8.
Small ; 20(22): e2307595, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38126648

RESUMO

In the osteoporotic microenvironment, the acidic microenvironment generated by excessive osteoclasts not only causes irreversible bone mineral dissolution, but also promotes reactive oxygen species (ROS) production to induce osteoblast senescence and excessive receptor activator of nuclear factor kappa-B ligand (RANKL) production, which help to generate more osteoclasts. Hence, targeting the acidic microenvironment and RANKL production may break this vicious cycle to rescue osteoporosis. To achieve this, an acid-responsive and neutralizing system with high in vivo gene editing capacity is developed by loading sodium bicarbonate (NaHCO3) and RANKL-CRISPR/Cas9 (RC) plasmid in a metal-organic framework. This results showed ZIF8-NaHCO3@Cas9 (ZNC) effective neutralized acidic microenvironment and inhibited ROS production . Surprisingly, nanoparticles loaded with NaHCO3 and plasmids show higher transfection efficiency in the acidic environments as compared to the ones loaded with plasmid only. Finally, micro-CT proves complete reversal of bone volume in ovariectomized mice after ZNC injection into the bone remodeling site. Overall, the newly developed nanoparticles show strong effect in neutralizing the acidic microenvironment to achieve bone protection through promoting osteogenesis and inhibiting osteolysis in a bidirectional manner. This study provides new insights into the treatment of osteoporosis for biomedical and clinical therapies.


Assuntos
Edição de Genes , Estruturas Metalorgânicas , Osteoclastos , Osteoporose , Animais , Osteoporose/metabolismo , Osteoclastos/metabolismo , Camundongos , Estruturas Metalorgânicas/química , Ligante RANK/metabolismo , Feminino , Sistemas CRISPR-Cas , Espécies Reativas de Oxigênio/metabolismo , Bicarbonato de Sódio/química , Ácidos/química , Nanopartículas/química , Osteogênese/efeitos dos fármacos , Plasmídeos/genética
9.
Ann Rheum Dis ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164066

RESUMO

OBJECTIVES: T helper 9 (Th9) cells are recognised for their characteristic expression of the transcription factor PU.1 and production of interleukin-9 (IL-9), which has been implicated in various autoimmune diseases. However, its precise relationship with rheumatoid arthritis (RA) pathogenesis needs to be further clarified. METHODS: The expression levels of PU.1 and IL-9 in patients with RA were determined by ELISA, western blotting (WB) and immunohistochemical staining. PU.1-T cell-conditional knockout (KO) mice, IL-9 KO and IL-9R KO mice were used to establish collagen antibody-induced arthritis (CAIA), respectively. The inhibitor of PU.1 and IL-9 blocking antibody was used in collagen-induced arthritis (CIA). In an in vitro study, the effects of IL-9 were investigated using siRNAs and IL-9 recombinant proteins. Finally, the underlying mechanisms were further investigated by luciferase reporter analysis, WB and Chip-qPCR. RESULTS: The upregulation of IL-9 expression in patients with RA exhibited a positive correlation with clinical markers. Using CAIA and CIA model, we demonstrated that interventions targeting PU.1 and IL-9 substantially mitigated the inflammatory phenotype. Furthermore, in vitro assays provided the proinflammatory role of IL-9, particularly in the hyperactivation of macrophages and fibroblast-like synoviocytes. Mechanistically, we uncovered that PU.1 and IL-9 form a positive feedback loop in RA: (1) PU.1 directly binds to the IL-9 promoter, activating its transcription and (2) Th9-derived IL-9 induces PU.1 via the IL-9R-JAK1/STAT3 pathway. CONCLUSIONS: These results support that the PU.1-IL-9 axis forms a positive loop in Th9 dysregulation of RA. Targeting this signalling axis presents a potential target approach for treating RA.

10.
Plant Physiol ; 191(2): 1017-1035, 2023 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-36417282

RESUMO

The fast growth of Moso bamboo (Phyllostachys edulis) shoots is caused by the rapid elongation of each internode. However, the key underlying cellular processes and epigenetic mechanisms remain largely unexplored. We used microscopy and multi-omics approaches to investigate two regions (bottom and middle) of the 18th internode from shoots of two different heights (2 and 4 m). We observed that internode cells become longer, and that lignin biosynthesis and glycosyltransferase family 43 (GT43) genes are substantially upregulated with shoot height. Nanopore direct RNA sequencing (DRS) revealed a higher N6-methyladenine (m6A) modification rate in 2-m shoots than in 4-m shoots. In addition, different specific m6A modification sites were enriched at different growth stages. Global DNA methylation profiling indicated that DNA methylation levels are higher in 4-m shoots than in 2-m shoots. We also detected shorter poly(A) tail lengths (PALs) in 4-m shoots compared with 2-m shoots. Genes showing differential PAL were mainly enriched in the functional terms of protein translation and vesicle fusion. An association analysis between PALs and DNA methylation strongly suggested that gene body CG methylation levels are positively associated with PAL. This study provides valuable information to better understand post-transcriptional regulations responsible for fast-growing shoots in Moso bamboo.


Assuntos
Regulação da Expressão Gênica de Plantas , Poaceae , Brotos de Planta/metabolismo , Poaceae/genética , RNA/metabolismo , Epigênese Genética
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