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1.
FASEB J ; 38(3): e23462, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38318662

RESUMO

Hibernation, a survival strategy in mammals for extreme climates, induces physiological phenomena such as ischemia-reperfusion and metabolic shifts that hold great potential for advancements in modern medicine. Despite this, the molecular mechanisms underpinning hibernation remain largely unclear. This study used RNA-seq and Iso-seq techniques to investigate the changes in liver transcriptome expression of Rhinolophus pusillus during hibernation and active periods, as well as under different microhabitat temperatures. We identified 11 457 differentially expressed genes during hibernation and active periods, of which 395 showed significant differential expression. Genes associated with fatty acid catabolism were significantly upregulated during hibernation, whereas genes related to carbohydrate metabolism and glycogen synthesis were downregulated. Conversely, immune-related genes displayed differential expression patterns: genes tied to innate immunity were significantly upregulated, while those linked to adaptive immunity and inflammatory response were downregulated. The analysis of transcriptomic data obtained from different microhabitat temperatures revealed that R. pusillus exhibited an upregulation of genes associated with lipid metabolism in lower microhabitat temperature. This upregulation facilitated an enhanced utilization rate of triglyceride, ultimately resulting in increased energy provision for the organism. Additionally, R. pusillus upregulated gluconeogenesis-related genes regardless of the microhabitat temperature, demonstrating the importance of maintaining blood glucose levels during hibernation. Our transcriptomic data reveal that these changes in liver gene expression optimize energy allocation during hibernation, suggesting that liver tissue adaptively responds to the inherent stress of its function during hibernation. This study sheds light on the role of differential gene expression in promoting more efficient energy allocation during hibernation. It contributes to our understanding of how liver tissue adapts to the stressors associated with this state.


Assuntos
Quirópteros , Hibernação , Animais , Transcriptoma , Hibernação/genética , Temperatura , Quirópteros/genética , Regulação da Expressão Gênica , Fígado/metabolismo
2.
Lupus ; 33(4): 403-408, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38407846

RESUMO

OBJECTIVE: Interleukin-18 (IL-18) is a proinflammatory cytokine. This study aims to determine whether there is a causal relationship between circulating IL-18 concentrations and the risk of inflammatory and autoimmune diseases. METHODS: We collected significant single nucleotide polymorphisms (SNPs) associated with circulating IL-18 levels (p < 5 × 10-8) as instrumental variables (IVs) from a genome-wide association study (GWAS) involving 21,758 individuals of European descent. We mainly employed the inverse-variance weighed (IVW) method of two-sample Mendelian randomization (TSMR) analysis to estimate the causality of circulating IL-18 levels on inflammatory and autoimmune diseases. RESULTS: The IVW method results showed evidence of a causal relationship between IL-18 and the risk of systemic lupus erythematosus (SLE) (OR = 1.32; 95% CI 1.15, 1.50; p < .001) and type 1 diabetes (T1D) (OR = 1.22; 95% CI 1.06, 1.42; p = .007) in individuals of European ancestry. No significant heterogeneity or horizontal pleiotropy for SLE and T1D was detected. The sensitivity analysis, which involved removing confounding SNP, produced similar results for SLE and T1D. The results of sensitivity analysis using leave-one-out method indicated no single SNP significantly influenced the analysis results. However, we did not find any significant findings for multiple sclerosis, psoriasis, asthma, and osteoarthritis. CONCLUSIONS: Our analyses suggest that circulating IL-18 is significantly related to SLE and T1D and may serve as a potential target for the treatment of these diseases.


Assuntos
Doenças Autoimunes , Diabetes Mellitus Tipo 1 , Lúpus Eritematoso Sistêmico , Humanos , Diabetes Mellitus Tipo 1/genética , Estudo de Associação Genômica Ampla , Interleucina-18/genética , Lúpus Eritematoso Sistêmico/genética
3.
Ann Rheum Dis ; 79(12): 1565-1571, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32868391

RESUMO

OBJECTIVES: The present study aimed to discover novel susceptibility loci associated with risk of rheumatoid arthritis (RA). METHODS: We performed a new genome-wide association study (GWAS) in Chinese subjects (1027 RA cases and 2879 controls) and further conducted an expanded meta-analysis with previous GWAS summary data and replication studies. The functional roles of the associated loci were interrogated using publicly available databases. Dual-luciferase reporter and cytokine assay were also used for exploring variant function. RESULTS: We identified five new susceptibility loci (IL12RB2, BOLL-PLCL1, CCR2, TCF7 and IQGAP1; pmeta <5.00E-08) with same effect direction in each study cohort. The sensitivity analyses showed that the genetic association of at least three loci was reliable and robust. All these lead variants are expression quantitative trait loci and overlapped with epigenetic marks in immune cells. Furthermore, genes within the five loci are genetically associated with risk of other autoimmune diseases, and genes within four loci are known functional players in autoimmunity, which supports the validity of our findings. The reporter assay showed that the risk allele of rs8030390 in IQGAP1 have significantly increased reporter activity in HEK293T cells. In addition, the cytokine assay found that the risk allele of rs244672 in TCF7 was most significantly associated with increased plasma IL-17A levels in healthy controls. Finally, identified likely causal genes in these loci significantly interacted with RA drug targets. CONCLUSION: This study identified novel RA risk loci and highlighted that comprehensive genetic study can provide important information for RA pathogenesis and drug therapy.


Assuntos
Artrite Reumatoide/genética , Predisposição Genética para Doença/genética , Povo Asiático/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos
4.
J Hum Genet ; 65(8): 675-681, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32313195

RESUMO

Previous studies are inconclusive on the relationships between BLK gene polymorphisms and clinical features of systemic lupus erythematosus (SLE). The present study aimed to estimate association between BLK loci and SLE clinical features in Chinese population. Associations between BLK single-nucleotide polymorphisms (SNPs) and susceptibility to SLE in this study were estimated using data of 1205 health controls previously reported in the same population. And a total of 814 SLE patients recruited from two different sources according with ACR criteria were analyzed for genotype-phenotype associations. A meta-analysis was conducted of the associations between BLK loci and renal disorder in SLE. The expression quantitative trait locus (eQTL) data were also extracted from the public databases for the selected SNPs. Significant associations were observed between these SNPs and susceptibility to SLE. In addition, the data showed that rs2618479 and rs7812879 were associated with renal disorder [OR = 1.51 (95% CI: 1.15, 1.99) and 1.61 (95% CI: 1.21, 2.14), Pcorr = 0.033 and 0.011, respectively] and proteinuria [OR = 1.47 (95% CI: 1.12, 1.95) and 1.52 (95% CI: 1.14, 2.03), Pcorr = 0.048 and 0.040, respectively]. The consistent associations were observed in two independent centers as well as new cases group. The result of meta-analysis for rs2618479 was also significant [OR = 1.35 (95% CI: 1.12, 1.62)]. In addition, bioinformatics analysis demonstrated that the two SNPs were significantly associated with the expression of BLK in whole blood and several immune cells. Our data support that variant loci of BLK are associated with presence of renal disorder in patients with SLE.


Assuntos
Nefropatias/genética , Lúpus Eritematoso Sistêmico/genética , Quinases da Família src/genética , Adulto , Povo Asiático/genética , Feminino , Estudos de Associação Genética , Humanos , Nefropatias/complicações , Nefropatias/fisiopatologia , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Quinases da Família src/sangue , Quinases da Família src/metabolismo
5.
J Org Chem ; 85(11): 6844-6853, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32412751

RESUMO

LCZ696 is a novel treatment for patients suffering from heart failure that combines the two active pharmaceutical ingredients sacubitril and valsartan in a single chemical compound. While valsartan is an established drug substance, a new manufacturing process suitable for large-scale commercial production had to be developed for sacubitril. The use of chemocatalysis, biocatalysis, and flow chemistry as state-of-the-art technologies allowed to efficiently build up the structure of sacubitril and achieve the defined performance targets.


Assuntos
Aminobutiratos , Antagonistas de Receptores de Angiotensina , Biocatálise , Compostos de Bifenilo , Combinação de Medicamentos , Humanos , Tetrazóis , Valsartana
6.
Microbiol Spectr ; 11(4): e0043323, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37378560

RESUMO

Variations in ambient temperature (Ta) may significantly influence the gut microbiotas of ectothermic and endothermic animals, affecting fitness. It remains unclear, however, whether temperature fluctuations affect the gut microbial communities of hibernating animals during torpor. To investigate temperature-induced changes in the gut microbiota during hibernation under entirely natural conditions, we took advantage of two adjacent but distinct populations of the least horseshoe bat (Rhinolophus pusillus), which inhabit sites with a similar summer Ta but a different winter Ta. Using 16S rRNA gene high-throughput sequencing, we estimated differences in gut microbial diversity and composition between the hibernating (winter) and active (summer) R. pusillus populations at both sites. During the active period, gut microbiotas did not differ significantly between the two populations, probably due to the similar Tas. However, during hibernation, a higher Ta was associated with decreased α-diversity in the gut microbiome. During hibernation, temperature variation did not significantly affect the relative abundance of Proteobacteria, the dominant phylum at both sites, but marked site-specific differences were detected in the relative abundances of Firmicutes, Actinobacteria, and Tenericutes. In total, 74 amplicon sequence variants (ASVs) were significantly differentially abundant between the hibernating and active bat guts across the two sites; most of these ASVs were associated with the cooler site, and many belonged to pathogenic genera, suggesting that lower ambient temperatures during hibernation may increase the risk of pathogen proliferation in the host gut. Our findings help to clarify the mechanisms underlying the gut microbiota-driven adaptation of hibernating mammals to temperature changes. IMPORTANCE Temperature variations affect gut microbiome diversity and structure in both ectothermic and endothermic animals. Here, we aimed to characterize temperature-induced changes in the gut microbiotas of adjacent natural populations of the least horseshoe bat (Rhinolophus pusillus) which hibernate at different ambient temperatures. We found that the ambient temperature significantly affected the α-diversity, but not the ß-diversity, of the gut microbiota. Bats hibernating at cooler temperatures experienced more drastic shifts in gut microbiome structure, with consequent effects on energy-related metabolic pathways. Our results provide novel insights into the effects of ambient temperature on the gut microbiotas of hibernating animals.


Assuntos
Quirópteros , Microbioma Gastrointestinal , Microbiota , Animais , Temperatura , RNA Ribossômico 16S/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-36634815

RESUMO

Dynamic epigenetic changes during hibernation occur in some hibernating rodents, but these changes are poorly understood in hibernating bats. Populations of the greater horseshoe bat (Rhinolophus ferrumequinum) in north China hibernate and provide an opportunity to study how epigenetic markers and modifiers differ in the active and torpid states of a chiropteran. We used fluorescence-labeled methylation-sensitive amplified polymorphism (F-MSAP) and qRT-PCR techniques to determine changes in the global DNA methylation levels and mRNA expression levels of methylation-related proteins. These included DNA methyltransferase (DNMTs), methyl-CpG-binding proteins (MBPs, including MBDs, UHRFs, and zinc-finger protein family) in active and torpid R. ferrumequinum. In the torpid state, both the relative global methylation and the relative mRNA expression levels of some DNMTs and MBPs, including dnmt3b and zbtb4, increased significantly compared to the expression levels of these in the active state. These changes may involve methylation or assist in regulation of a particular subset of genes according to hibernation status. This indicates that epigenetic mechanisms may exist and facilitate the hibernation process of R. ferrumequinum.


Assuntos
Quirópteros , Epigênese Genética , Hibernação , Animais , China , Quirópteros/genética , Quirópteros/metabolismo , Hibernação/genética , RNA Mensageiro/genética
8.
Arthritis Rheumatol ; 74(12): 1984-1990, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35830513

RESUMO

OBJECTIVE: Previous observational studies demonstrated that a subset of patients with systemic lupus erythematosus (SLE) have markedly short telomere length in leukocytes. This study was undertaken to test whether leukocyte telomere length is causally associated with risk of SLE. METHODS: A 2-sample Mendelian randomization (MR) analysis was conducted to estimate causality of telomere length on SLE in European populations. A replication 2-sample MR study using Asian genetic data was also conducted. A reverse MR analysis was then performed to test the effects of SLE on telomere length. The autoantibodies targeting telomere-associated protein (telomeric repeat-binding factor 1 [TERF1] autoantibodies) were detected in patients with SLE, healthy controls, and patients with rheumatoid arthritis. RESULTS: The results of the inverse variance-weighted method (odds ratio [OR] 2.96 [95% confidence interval (95% CI) 1.58-5.55], P < 0.001) showed strong evidence for a causal relationship between longer telomere length and risk of SLE in people with European ancestry. The outcomes of MR-Egger regression analysis (OR 29.46 [95% CI 3.02-287.60], P = 0.033) and MR pleiotropy residual sum and outlier analysis (OR 3.62 [95% CI 2.03-6.46], P = 0.002) also showed that longer telomere length was significantly associated with increased risk of SLE in a European population. Sensitivity analyses using different methods and summary data sets showed that the results were still broadly consistent. A replication MR study using Asian genetic data yielded similar findings. However, the reverse MR analysis showed that genetically predicted SLE was not causally associated with telomere length. In addition, we found that TERF1 autoantibodies were present in 2 of 40 SLE patients (5.0%). CONCLUSION: In contrast with previous observational studies, MR analyses show that longer telomere length is significantly associated with increased risk of SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Análise da Randomização Mendeliana , Humanos , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Lúpus Eritematoso Sistêmico/epidemiologia , Telômero/genética , Autoanticorpos/genética
9.
Chemistry ; 17(23): 6484-91, 2011 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-21538618

RESUMO

A highly efficient and enantioselective intramolecular crossed Rauhut-Currier (RC) reaction of nitroolefins with tethered enonates has been developed through cooperative nucleophilic activation and a hydrogen-bonding catalytic strategy (≤98% ee and 98% yield). The reaction features simple experimental procedures and is completely chemoselective and atom-economic in character. The potential synthetic applications have been demonstrated by the conversion of the RC reaction products into biologically and pharmaceutically valuable compounds with highly diastereoselectivity. In addition, computational investigations were employed to support the proposed mechanism and to obtain a good understanding of the origin of the stereoselectivity in RC reactions.


Assuntos
Alcenos/química , Reagentes de Ligações Cruzadas/química , Nitrocompostos/química , Catálise , Técnicas de Química Combinatória , Ligação de Hidrogênio , Estrutura Molecular , Estereoisomerismo
10.
Ann Med ; 53(1): 824-829, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34060972

RESUMO

OBJECTIVE: To investigated the association between single nucleotide polymorphisms (SNPs) in microRNA-146a (miR-146a) gene and susceptibility of rheumatoid arthritis (RA). METHODS: We systemically extracted the genetic data of miR-146a from previous genome-wide association studies (GWASs) of RA. Subsequently, we performed a replication study in an independent Chinese cohort for selected variant. A meta-analysis combined the previous GWASs with the replication study was also conducted. The epigenetic annotation and cytokine assay were used for exploring potential variant function. RESULTS: The extracted genetic association data from three previous GWASs showed that the allele T of functional SNP rs2431697 increased RA susceptibility. The significant association for the SNP was also found in the Chinese replication cohort (OR = 1.24, 95% CI = 1.06-1.46, p = 8.69E-03). The estimated effect size for this SNP was larger in Asian population than that in European population (Asian meta-analysis: OR = 1.15, 95% CI = 1.09-1.22, p = 4.37E-07; Tran-ethnic meta-analysis: OR = 1.07, 95% CI = 1.04-1.10, p = 1.79E-06). The cytokine assay also showed that the risk allele T of the SNP rs2431697 is inversely associated with plasma TNF-α levels in health controls (p = .016). CONCLUSIONS: In summary, this study supports that genetic variant in miR-146a gene is associated with RA risk.KEY MESSAGESThe association between SNPs in miR-146a gene and susceptibility of RA was unclear.We investigated the genetic association using GWASs data and a replication study.The SNP rs2431697 in miR-146a gene is associated with RA risk.


Assuntos
Artrite Reumatoide , MicroRNAs , Artrite Reumatoide/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa
11.
Chemistry ; 15(12): 2742-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19204966

RESUMO

Economical approach: The first organocatalytic asymmetric intramolecular hydroarylation of phenol- and aniline-derived enals offers one of the most straightforward and atom-economic approaches to enantioriched chromans and tetrahydroquinolines (up to 96% ee; see scheme).


Assuntos
Aldeídos/química , Compostos de Anilina/química , Cromanos/síntese química , Quinolinas/síntese química , Catálise , Cromanos/química , Técnicas de Química Combinatória , Estrutura Molecular , Quinolinas/química , Estereoisomerismo
12.
Chem Commun (Camb) ; (28): 4251-3, 2009 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-19585037

RESUMO

A useful Michael addition reaction using nitroalkanes as the nucleophile and 4-oxo-enoates as the Michael acceptor has been disclosed, and the reaction allows expedient access to functionalized chiral gamma-keto esters in high yields and excellent enantioselectivities (up to 98% ee), with a low catalyst loading.


Assuntos
Alcanos/química , Butiratos/química , Nitrocompostos/química , Compostos Orgânicos/química , Catálise , Cristalografia por Raios X , Modelos Moleculares , Estereoisomerismo
13.
J Org Chem ; 74(9): 3532-5, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19334694

RESUMO

A Brønsted acid catalyzed tandem Diels-Alder/aromatization reaction of 2-vinylindoles has been developed. The reaction provides a highly efficient and concise approach to 3-indolyl-substituted tetrahydrocarbazoles with various substituents in high yields under mild conditions.


Assuntos
Indóis/química , Ácido Trifluoracético/química , Carbazóis/química , Catálise
14.
J Org Chem ; 73(15): 6006-9, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18572922

RESUMO

A new class of organocatalysts has been designed by rational combination of proline with cinchona alkaloids. The chiral amine 3a, prepared from l-proline and cinchonidine, has been found to be an efficient catalyst for the direct aldol reactions of acetone or 2-butanone with a wide range of aldehydes (up to 98% ee). The cinchonidine backbone is essential to the reaction efficiency and enantioselectivity.


Assuntos
Aldeídos/química , Cetonas/química , Aminas/química , Catálise , Estrutura Molecular , Nitrobenzenos/química , Estereoisomerismo
15.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): o384, 2008 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-21201414

RESUMO

In the title compound, C(16)H(21)INO(4)P, the mol-ecular structure is stabilized by a weak intra-molecular C-H⋯O hydrogen-bond inter-action. The crystal packing is stabilized by strong inter-molecular O-H ⋯ O hydogen-bonding inter-actions to form a zigzag packing arrangement.

16.
Accid Anal Prev ; 106: 480-491, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27720427

RESUMO

To reduce exposure to risky and challenging driving situations and prolong mobility and independence, older drivers self-regulate their driving behavior. But self-regulation can be challenging because it depends on drivers' ability to assess their limitations. Studies using self-reports, survey data, and hazard and risk perception tests have shown that driving behavior feedback can help older drivers assess their limitations and adjust their driving behavior. But only limited work has been conducted in developing feedback technology interventions tailored to meet the information needs of older drivers, and the impact these interventions have in helping older drivers self-monitor their driving behavior and risk outcomes. The vehicles of 33 drivers 65 years and older were instrumented with OBD2 devices. Older drivers were provided access to customized web-based Trip Diaries that delivered post-trip feedback of the routes driven, low-risk route alternatives, and frequency of their risky driving behaviors. Data were recorded over four months, with baseline driving behavior collected for one month. Generalized linear mixed effects regression models assessed the effects of post-trip feedback on the route risk and driving behaviors of older drivers. Results showed that post-trip feedback reduced the estimated route risk of older drivers by 2.9% per week, and reduced their speeding frequency on average by 0.9% per week. Overall, the Trip Diary feedback reduced the expected crash rate from 1 in 6172 trips to 1 in 7173 trips, and the expected speeding frequency from 46% to 39%. Thus providing older drivers with tailored feedback of their driving behavior and crash risk could help them appropriately self-regulate their driving behavior, and improve their crash risk outcomes.


Assuntos
Envelhecimento/psicologia , Condução de Veículo/psicologia , Acidentes de Trânsito/prevenção & controle , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Condução de Veículo/estatística & dados numéricos , Retroalimentação , Feminino , Humanos , Masculino , Risco , Assunção de Riscos , Autorrelato
18.
Org Lett ; 13(4): 808-11, 2011 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-21247143

RESUMO

A catalytic asymmetric aza-Michael-Michael addition cascade of anilines to nitroolefin enoates in the presence of chiral bifunctional thiourea catalysts has been disclosed. This reaction provides a mild and efficient approach to polysubstituted chiral 4-aminobenzopyrans bearing three consecutive stereocenters in high yields with excellent stereoselectivities.


Assuntos
Benzopiranos/síntese química , Tioureia/química , Alcenos/química , Compostos de Anilina/química , Benzopiranos/química , Catálise , Técnicas de Química Combinatória , Estrutura Molecular , Nitrocompostos/química , Estereoisomerismo
19.
Org Lett ; 12(5): 1140-3, 2010 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20146508

RESUMO

A hydrogen bonding-mediated double Michael addition-aromatization cascade of 2-propenylindoles and nitroolefins has been disclosed. The methodology allows an efficient synthesis of diverse and structurally complex tetrahydrocarbazoles in good to excellent enantioselectivities and diastereoselectivities.


Assuntos
Carbazóis/química , Alcenos/química , Catálise , Ligação de Hidrogênio , Estereoisomerismo , Especificidade por Substrato , Sulfonamidas/química
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