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1.
Proc Natl Acad Sci U S A ; 121(20): e2320674121, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38684007

RESUMEN

Identifying and protecting hotspots of endemism and species richness is crucial for mitigating the global biodiversity crisis. However, our understanding of spatial diversity patterns is far from complete, which severely limits our ability to conserve biodiversity hotspots. Here, we report a comprehensive analysis of amphibian species diversity in China, one of the most species-rich countries on Earth. Our study combines 20 y of field surveys with new molecular analyses of 521 described species and also identifies 100 potential cryptic species. We identify 10 hotspots of amphibian diversity in China, each with exceptional species richness and endemism and with exceptional phylogenetic diversity and phylogenetic endemism (based on a new time-calibrated, species-level phylogeny for Chinese amphibians). These 10 hotspots encompass 59.6% of China's described amphibian species, 49.0% of cryptic species, and 55.6% of species endemic to China. Only four of these 10 hotspots correspond to previously recognized biodiversity hotspots. The six new hotspots include the Nanling Mountains and other mountain ranges in South China. Among the 186 species in the six new hotspots, only 9.7% are well covered by protected areas and most (88.2%) are exposed to high human impacts. Five of the six new hotspots are under very high human pressure and are in urgent need of protection. We also find that patterns of richness in cryptic species are significantly related to those in described species but are not identical.


Asunto(s)
Anfibios , Biodiversidad , Filogenia , Animales , Anfibios/clasificación , China , Conservación de los Recursos Naturales
2.
Nature ; 575(7781): 203-209, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31666698

RESUMEN

Accumulation of mutant proteins is a major cause of many diseases (collectively called proteopathies), and lowering the level of these proteins can be useful for treatment of these diseases. We hypothesized that compounds that interact with both the autophagosome protein microtubule-associated protein 1A/1B light chain 3 (LC3)1 and the disease-causing protein may target the latter for autophagic clearance. Mutant huntingtin protein (mHTT) contains an expanded polyglutamine (polyQ) tract and causes Huntington's disease, an incurable neurodegenerative disorder2. Here, using small-molecule-microarray-based screening, we identified four compounds that interact with both LC3 and mHTT, but not with the wild-type HTT protein. Some of these compounds targeted mHTT to autophagosomes, reduced mHTT levels in an allele-selective manner, and rescued disease-relevant phenotypes in cells and in vivo in fly and mouse models of Huntington's disease. We further show that these compounds interact with the expanded polyQ stretch and could lower the level of mutant ataxin-3 (ATXN3), another disease-causing protein with an expanded polyQ tract3. This study presents candidate compounds for lowering mHTT and potentially other disease-causing proteins with polyQ expansions, demonstrating the concept of lowering levels of disease-causing proteins using autophagosome-tethering compounds.


Asunto(s)
Alelos , Evaluación Preclínica de Medicamentos/métodos , Proteína Huntingtina/antagonistas & inhibidores , Proteína Huntingtina/genética , Proteínas Mutantes/antagonistas & inhibidores , Proteínas Mutantes/genética , Mutación/genética , Animales , Ataxina-3/genética , Autofagosomas/metabolismo , Autofagia , Modelos Animales de Enfermedad , Proteínas de Drosophila/antagonistas & inhibidores , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Femenino , Humanos , Proteína Huntingtina/química , Proteína Huntingtina/metabolismo , Masculino , Ratones , Proteínas Asociadas a Microtúbulos/genética , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Mutación/efectos de los fármacos , Neuronas/citología , Péptidos/genética , Fenotipo , Reproducibilidad de los Resultados
3.
Stem Cells ; 41(1): 11-25, 2023 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-36318802

RESUMEN

As crucial epigenetic regulators, long noncoding RNAs (lncRNAs) play critical functions in development processes and various diseases. However, the regulatory mechanism of lncRNAs in early heart development is still limited. In this study, we identified cardiac mesoderm-related lncRNA (LncCMRR). Knockout (KO) of LncCMRR decreased the formation potential of cardiac mesoderm and cardiomyocytes during embryoid body differentiation of mouse embryonic stem (ES) cells. Mechanistic analyses showed that LncCMRR functionally interacted with the transcription suppressor PURB and inhibited its binding potential at the promoter region of Flk1, which safeguarded the transcription of Flk1 during cardiac mesoderm formation. We also carried out gene ontology term and signaling pathway enrichment analyses for the differentially expressed genes after KO of LncCMRR, and found significant correlation of LncCMRR with cardiac muscle contraction, dilated cardiomyopathy, and hypertrophic cardiomyopathy. Consistently, the expression level of Flk1 at E7.75 and the thickness of myocardium at E17.5 were significantly decreased after KO of LncCMRR, and the survival rate and heart function index of LncCMRR-KO mice were also significantly decreased as compared with the wild-type group. These findings indicated that the defects in early heart development led to functional abnormalities in adulthood heart of LncCMRR-KO mice. Conclusively, our findings elucidate the main function and regulatory mechanism of LncCMRR in cardiac mesoderm formation, and provide new insights into lncRNA-mediated regulatory network of mouse ES cell differentiation.


Asunto(s)
ARN Largo no Codificante , Animales , Ratones , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Ratones Noqueados , Diferenciación Celular/genética , Miocardio , Miocitos Cardíacos , Mesodermo/metabolismo
4.
FASEB J ; 37(2): e22749, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36688808

RESUMEN

Tacrolimus (TAC)-induced renal injury is detrimental to long-term kidney function, but a treatment medication is not available. Glycyrrhizic acid (GA) is an active ingredient in licorice widely used to treat kidney disease. Thus, this study explored the mechanisms of renoprotection by GA on TAC-induced renal injury. C57BL/6 mice were subjected daily to TAC or a combination of TAC and GA for 4 weeks, and then renal function, histopathology, and autophagy were assessed to examine the effect of GA on a renal injury. Next, Human kidney proximal tubular epithelial (HK-2) cells were pretreated with GA for 2 h and then treated with TAC for 24 h. The effect of GA on TAC-induced HK-2 cell injury was assessed by measuring cell viability, apoptosis, autophagy, and lysosomes. Mice exposed to TAC and treated with GA had significantly greater improvements in renal function and tubulointerstitial fibrosis in comparison to mice not treated with GA. In addition, fibrosis-related protein expression, including α-smooth muscle actin and fibronectin, decreased after GA treatment. GA treatment also relieved autophagic clearance in TAC-induced renal injury. Several in vitro studies found that TAC inhibited cell viability, autophagy, lysosomal acidification, and promoted apoptosis. However, these results were less pronounced with GA pretreatment. In addition, bafilomycin A1 (which inhibits lysosomal function) reduced the protective effect of GA, indicating that lysosomal function plays an important role in this effect. Our data suggest that GA improves lysosomal function and regulates autophagy to protect against TAC-induced renal injury.


Asunto(s)
Enfermedades Renales , Tacrolimus , Ratones , Humanos , Animales , Tacrolimus/farmacología , Ácido Glicirrínico/metabolismo , Ácido Glicirrínico/farmacología , Ratones Endogámicos C57BL , Riñón/metabolismo , Autofagia , Enfermedades Renales/patología
5.
Lipids Health Dis ; 23(1): 98, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570797

RESUMEN

Pulmonary fibrosis (PF) is a severe pulmonary disease with limited available therapeutic choices. Recent evidence increasingly points to abnormal lipid metabolism as a critical factor in PF pathogenesis. Our latest research identifies the dysregulation of low-density lipoprotein (LDL) is a new risk factor for PF, contributing to alveolar epithelial and endothelial cell damage, and fibroblast activation. In this study, we first integrative summarize the published literature about lipid metabolite changes found in PF, including phospholipids, glycolipids, steroids, fatty acids, triglycerides, and lipoproteins. We then reanalyze two single-cell RNA-sequencing (scRNA-seq) datasets of PF, and the corresponding lipid metabolomic genes responsible for these lipids' biosynthesis, catabolism, transport, and modification processes are uncovered. Intriguingly, we found that macrophage is the most active cell type in lipid metabolism, with almost all lipid metabolic genes being altered in macrophages of PF. In type 2 alveolar epithelial cells, lipid metabolic differentially expressed genes (DEGs) are primarily associated with the cytidine diphosphate diacylglycerol pathway, cholesterol metabolism, and triglyceride synthesis. Endothelial cells are partly responsible for sphingomyelin, phosphatidylcholine, and phosphatidylethanolamines reprogramming as their metabolic genes are dysregulated in PF. Fibroblasts may contribute to abnormal cholesterol, phosphatidylcholine, and phosphatidylethanolamine metabolism in PF. Therefore, the reprogrammed lipid profiles in PF may be attributed to the aberrant expression of lipid metabolic genes in different cell types. Taken together, these insights underscore the potential of targeting lipid metabolism in developing innovative therapeutic strategies, potentially leading to extended overall survival in individuals affected by PF.


Asunto(s)
Fibrosis Pulmonar , Humanos , Fibrosis Pulmonar/genética , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/patología , Análisis de Expresión Génica de una Sola Célula , Metabolismo de los Lípidos/genética , Células Endoteliales/metabolismo , Fosfolípidos/metabolismo , Colesterol/metabolismo , Fosfatidilcolinas
6.
Pharmacol Res ; 189: 106680, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36746359

RESUMEN

Acute kidney injury (AKI) is a common clinical complication. Cisplatin (Cis) is an effective chemotherapeutic drug; however, its acute nephrotoxicity often limits its application. The role of liraglutide (Lir), an agonist of the glucagon-like peptide-1 receptor (GLP-1R), has recently attracted increasing attention beyond glycemic regulation. This study showed that Lir significantly ameliorated Cis-induced kidney dysfunction and renal damage. However, this renoprotective effect was partially abolished in GLP-1R knockout (GLP-1R-/-) mice. Furthermore, we synthesized Lir metabolites, GLP-1 (9-37) and GLP-1 (28-37), and found that they also exerted reno-protective effects that were not impaired in GLP-1R-/- mice. We also demonstrated that Lir and its metabolites reduced cisplatin-induced apoptosis in human renal tubular epithelial cells (HK-2). After silencing GLP-1R expression in HK-2 cells with small interfering ribose nucleic acid (siRNA), the protective effect of Lir on HK-2 cells was inhibited, while the protective effects of GLP-1 (9-37) and GLP-1 (28-37) were not affected. Additionally, we demonstrated that Lir and its metabolites inhibited Cis-induced high-mobility group box 1 (HMGB1) nuclear-cytoplasmic translocation and release, and reduced inflammatory cytokines and HMGB1 receptor expression. The exogenous use of recombinant HMGB1 (rHMGB1) dramatically weakened the protective effects of Lir and its metabolites. In conclusion, our study shows that Lir significantly attenuated Cis-induced AKI through GLP-1R dependent and independent pathways, mediated by inhibiting nuclear-cytoplasmic translocation and release of HMGB1. Lir and its metabolites may be effective drugs for treating cisplatin-induced nephrotoxicity.


Asunto(s)
Lesión Renal Aguda , Proteína HMGB1 , Ratones , Humanos , Animales , Liraglutida/farmacología , Cisplatino , Péptido 1 Similar al Glucagón/uso terapéutico , Lesión Renal Aguda/tratamiento farmacológico , Receptor del Péptido 1 Similar al Glucagón/agonistas
7.
Nucleic Acids Res ; 49(4): 1935-1950, 2021 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-33544864

RESUMEN

Long noncoding RNAs (lncRNAs) play a wide range of roles in the epigenetic regulation of crucial biological processes, but the functions of lncRNAs in cortical development are poorly understood. Using human embryonic stem cell (hESC)-based 2D neural differentiation approach and 3D cerebral organoid system, we identified that the lncRNA PAUPAR, which is adjacent to PAX6, plays essential roles in cortical differentiation by interacting with PAX6 to regulate the expression of a large number of neural genes. Mechanistic studies showed that PAUPAR confers PAX6 proper binding sites on the target neural genes by directly binding the genomic regions of these genes. Moreover, PAX6 recruits the histone methyltransferase NSD1 through its C-terminal PST enrichment domain, then regulate H3K36 methylation and the expression of target genes. Collectively, our data reveal that the PAUPAR/PAX6/NSD1 complex plays a critical role in the epigenetic regulation of hESC cortical differentiation and highlight the importance of PAUPAR as an intrinsic regulator of cortical differentiation.


Asunto(s)
Corteza Cerebral/metabolismo , Células Madre Embrionarias/metabolismo , Regulación de la Expresión Génica , Factor de Transcripción PAX6/metabolismo , ARN Largo no Codificante/metabolismo , Sitios de Unión , Diferenciación Celular/genética , Células Cultivadas , Células Madre Embrionarias/citología , Eliminación de Gen , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/metabolismo , Humanos , Metilación , Organoides , ARN Largo no Codificante/genética
8.
Pharmacol Res ; 178: 106161, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35259481

RESUMEN

Renal fibrosis is a non-negligible pathological change in chronic kidney disease (CKD). Increasing evidence indicates that macrophage and gut-kidney axis are correlated with CKD. In this study, we manifest that pharmacological modulating macrophage phenotype via gut-kidney axis is conducive to the alleviation of renal fibrosis. Employing wild-type male mice with unilateral ureteral obstruction (UUO), renal fibrosis was dramatically mitigated in mice treated with antibiotics. And antibiotics application restricted the synthesis of intestinal flora metabolite Trimethylamine N-Oxide (TMAO). However, a 1.3% choline diet enhanced fibrosis. Then we further examined macrophage phenotype through the gut-kidney axis. In in vivo and in vitro culture experiments, the mRNA expression of Nos2, Tnf-α, Il-6, and Il-1ß increased under TMAO stimulation. Curbing the NLRP3 inflammasome countered TMAO-induced M1 polarization in bone marrow-derived macrophages. This finding demonstrates that NLRP3 plays a critical part in macrophage polarization. Because of the declining M1 polarization trend in the early stage, M2 macrophages undoubtedly decreased in the tissues. Our results revealed that some metabolites could regulate macrophage phenotype, which matters the severity of renal fibrosis. Thus, pharmacological targeting macrophage phenotype via gut-kidney axis may be a different strategy to treat renal fibrosis.


Asunto(s)
Proteína con Dominio Pirina 3 de la Familia NLR , Insuficiencia Renal Crónica , Animales , Antibacterianos/uso terapéutico , Modelos Animales de Enfermedad , Fibrosis , Riñón/patología , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Fenotipo , Insuficiencia Renal Crónica/metabolismo
9.
Stem Cells ; 2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-32997855

RESUMEN

Embryonic stem (ES) cells have the property of self-renewal and multi-directional differentiation, and provide an ideal model for studying early embryo development in vitro. Wnt3, as Wnt family member 3, plays a vital role during ES cell differentiation. However, the exact regulatory mechanism of Wnt3 remains to be elucidated. MicroRNAs can directly regulate gene expression at the post-transcriptional level and play critical function in cell fate determination. Here, we found the expression level of miR-184 decreased when ES cells differentiated into cardiac mesoderm then increased during the process as differentiated into cardiomyocytes, which negatively correlated with the expression of Wnt3. Overexpression of miR-184 during the process of ES cell differentiation into cardiac mesoderm repressed cardiac mesoderm differentiation and cardiomyocyte formation. Bioinformatics prediction and mechanism studies showed that miR-184 directly bound to the 3'UTR region of Wnt3 and inhibited the expression level of Wnt3. Consistently, knockdown of Wnt3 mimicked the effects of miR-184-overexpression on ES cell differentiation into cardiac mesoderm, whereas overexpression of Wnt3 rescued the inhibition effects of miR-184 overexpression on ES cell differentiation. These findings demonstrated that miR-184 is a direct regulator of Wnt3 during the differentiation process of ES cells, further enriched the epigenetic regulatory network of ES cell differentiation into cardiac mesoderm and cardiomyocytes.

10.
Stem Cells ; 38(3): 340-351, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31778238

RESUMEN

Embryonic stem cells (ESCs) have self-renewal and multi-lineage differentiation potential and perform critical functions in development and biomedicine. Several long noncoding RNAs (lncRNAs) have been reported as key regulators of stem cell pluripotency and differentiation. However, the function and regulatory mechanism of lncRNAs during the initiation of ESC differentiation remains unclear. Here, we found that linc1557 was highly expressed in mouse ESCs and required for the initiation of ESC differentiation. Knockdown of linc1557 increased the expression and phosphorylation levels of signal transducer and activator of transcription 3 (STAT3), a key factor in the leukemia inhibitory factor (LIF)/STAT3 signaling pathway. Furthermore, we found that linc1557 directly bound to Stat3 mRNA and affected its stability. The differentially expressed transcriptome after linc1557 knockdown in ESCs was involved primarily in multicellular organism development and cell differentiation as similar to that after Stat3 knockdown. Moreover, either knockdown of Stat3 or addition of a LIF/STAT3 signaling inhibitor rescued the suppressive effects of linc1557 knockdown on the initiation of mouse ESC differentiation. These findings not only elucidated the critical function of linc1557 in the initiation of mouse ESC differentiation but also clarified that its specific mechanism as directly affecting Stat3 mRNA stability, which enhanced the understanding of the lncRNA-mediated regulatory mechanism for mRNA stability and key signaling pathways in ESC pluripotency and differentiation.


Asunto(s)
Factor Inhibidor de Leucemia/metabolismo , Células Madre Embrionarias de Ratones/metabolismo , Animales , Diferenciación Celular , Ratones , Factor de Transcripción STAT3 , Transducción de Señal
11.
Biogerontology ; 21(5): 637-652, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32372324

RESUMEN

Aging dramatically increases the risk of cardiovascular diseases in human. Animal models are of great value to study cardiac aging, and zebrafish have become a popular model for aging study recently. However, there is limited knowledge about the progression and regulation of cardiac aging in zebrafish. In this study we first validated the effectiveness of a panel of aging-related markers and revealed their spatial-temporal specificity. Using these markers, we discovered that cardiac aging in zebrafish initiated at mid-age around 24 months, followed by a gradual progression marked with increased DNA damage, inflammatory response and reduced mitochondrial function. Furthermore, we showed aging-related expression profile change in zebrafish hearts was similar to that in rat hearts. Overall, our results provide a deeper insight into the cardiac aging process in zebrafish, which will set up foundation for generating novel cardiac aging models suitable for large scale screening of pharmaceutical targets.


Asunto(s)
Envejecimiento , Corazón/fisiología , Transcriptoma , Pez Cebra , Animales , Daño del ADN , Inflamación , Mitocondrias Cardíacas , Modelos Animales , Pez Cebra/genética
12.
Stem Cells ; 36(3): 325-336, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29205638

RESUMEN

Clarifying the regulatory mechanisms of embryonic stem cell (ESC) neural differentiation is helpful not only for understanding neural development but also for obtaining high-quality neural progenitor cells required by stem cell therapy of neurodegenerative diseases. Here, we found that long noncoding RNA 1604 (lncRNA-1604) was highly expressed in cytoplasm during neural differentiation, and knockdown of lncRNA-1604 significantly repressed neural differentiation of mouse ESCs both in vitro and in vivo. Bioinformatics prediction and mechanistic analysis revealed that lncRNA-1604 functioned as a novel competing endogenous RNA of miR-200c and regulated the core transcription factors ZEB1 and ZEB2 during neural differentiation. Furthermore, we also demonstrated the critical role of miR-200c and ZEB1/2 in mouse neural differentiation. Either introduction of miR-200c sponge or overexpression of ZEB1/2 significantly reversed the lncRNA-1604 knockdown-induced repression of mouse ESC neural differentiation. Collectively, these findings not only identified a previously unknown role of lncRNA-1604 and ZEB1/2 but also elucidated a new regulatory lncRNA-1604/miR-200c/ZEB axis in neural differentiation. Stem Cells 2018;36:325-336.


Asunto(s)
MicroARNs/metabolismo , Neuronas/citología , Neuronas/metabolismo , ARN Largo no Codificante/metabolismo , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc/metabolismo , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo , Animales , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Línea Celular , Biología Computacional/métodos , Transición Epitelial-Mesenquimal/genética , Transición Epitelial-Mesenquimal/fisiología , Ratones , MicroARNs/genética , ARN Largo no Codificante/genética , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genética
13.
Proc Natl Acad Sci U S A ; 110(8): 2858-63, 2013 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-23386720

RESUMEN

Fibroblasts can be reprogrammed to induced pluripotent stem cells (iPSCs) by application of transcription factors octamer-binding protein 4 (Oct4), SRY-box containing gene 2 (Sox2), Kruppel-like factor 4 (Klf4), and c-Myelocytomatosis oncogene (c-Myc) (OSKM), but the underlying mechanisms remain unclear. Here, we report that exogenous Oct4 and Sox2 can bind at the promoter regions of mir-141/200c and mir-200a/b/429 cluster, respectively, and induce the transcription activation of miR-200 family during the OSKM-induced reprogramming. Functional suppression of miR-200s with specific inhibitors significantly represses the OSKM-caused mesenchymal-to-epithelial transition (MET, an early event in reprogramming of fibroblasts to iPSCs) and iPSC generation, whereas overexpression of miR-200s promotes the MET and iPSC generation. Mechanistic studies showed that miR-200s significantly repress the expression of zinc finger E-box binding homeobox 2 (ZEB2) through directly targeting its 3' UTR and direct inhibition of ZEB2 can mimic the effects of miR-200s on iPSC generation and MET process. Moreover, the effects of miR-200s during iPSC generation can be blocked by ZEB2 overexpression. Collectively, our findings not only reveal that members of the miR-200 family are unique mediators of the reprogramming factors Oct4/Sox2, but also demonstrate that the miR-200/ZEB2 pathway as one critical mechanism of Oct4/Sox2 to induce somatic cell reprogramming at the early stage.


Asunto(s)
Transición Epitelial-Mesenquimal , Proteínas de Homeodominio/metabolismo , MicroARNs/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Células Madre Pluripotentes/citología , Proteínas Represoras/metabolismo , Factores de Transcripción SOXB1/metabolismo , Animales , Sitios de Unión , Diferenciación Celular , Células Cultivadas , Factor 4 Similar a Kruppel , Ratones , Células Madre Pluripotentes/metabolismo , Regiones Promotoras Genéticas , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc
14.
Eur Heart J ; 35(11): 733-42, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23798577

RESUMEN

AIMS: Elevated homocysteine levels are known to be a risk factor for congenital heart disease (CHD), but the mechanism underlying this effect is unknown. During early embryonic development, homocysteine removal is dictated exclusively by the MTR activity. To examine the role of MTR in CHD risk, we identified genetic variants in MTR and investigated the mechanisms that affect its expression levels and that increase the risk of CHD in Chinese populations. METHODS AND RESULTS: The association between regulatory variants of the MTR gene and CHD was examined in three independent case-control studies in a total of 2340 patients with CHD and 2270 controls. The functional consequences of these variants were demonstrated using dual-luciferase assays, real-time polymerase chain reaction (PCR), electrophoretic mobility shift assays, surface plasma resonance, chromatin immunoprecipitation, and bisulfite sequencing, as well as by a group of predicted microRNAs using a gene reporter system. Two regulatory variants of MTR, -186T>G and +905G>A, were associated with an increased risk of CHD in both the separate and combined case-control studies (-186GG P = 1.32 × 10(-9); +905AA P = 6.35 × 10(-14)). Compared with the major allele, the -186G allele exhibited significantly lower promoter activity, decreased hnRNA and mRNA levels, reduced transcription factor binding affinity, and a more highly methylated promoter. The +905A allele exhibited a statistically stronger binding affinity to functional microRNAs that down regulate MTR expression at the translational level. Both of the minor alleles were correlated with elevated plasma homocysteine concentrations, indicating a genetic component for hyperhomocysteinaemia. CONCLUSIONS: Regulatory variants of the MTR gene increase CHD risk by reducing MTR expression and inducing the homocysteine accumulation and elevation.


Asunto(s)
5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/genética , Cardiopatías Congénitas/genética , Pueblo Asiatico/genética , Estudios de Casos y Controles , Metilación de ADN/genética , Ferredoxina-NADP Reductasa/genética , Expresión Génica/genética , Predisposición Genética a la Enfermedad/genética , Genotipo , Homocisteína/metabolismo , Humanos , Hiperhomocisteinemia/genética , MicroARNs/genética , Factores de Riesgo , Transcripción Genética/genética
15.
Front Nutr ; 10: 1127845, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37032786

RESUMEN

Introduction: The ketogenic diet (KD), as a dietary intervention, has gained importance in the treatment of solid organ structural remodeling, but its role in renal fibrosis has not been explored. Methods: Male C57BL/6 mice were fed a normal diet or a KD for 6 weeks prior to unilateral ureteral obstruction (UUO), a well-established in vivo model of renal fibrosis in rodents. Seven days after UUO, serum and kidney samples were collected. Serum ß-hydroxybutyrate (ß-OHB) concentrations and renal fibrosis were assessed. NRK52E cells were treated with TGFß1, a fibrosis-inducing cytokine, and with or without ß-OHB, a ketone body metabolized by KD, to investigate the mechanism underlying renal fibrosis. Results: KD significantly enhanced serum ß-OHB levels in mice. Histological analysis revealed that KD alleviated structural destruction and fibrosis in obstructed kidneys and reduced the expression of the fibrosis protein markers α-SMA, Col1a1, and Col3a1. Expression of the rate-limiting enzymes involved in fatty acid oxidation (FAO), Cpt1a and Acox1, significantly decreased after UUO and were upregulated by KD. However, the protective effect of KD was abolished by etomoxir (a Cpt1a inhibitor). Besides, our study observed that KD significantly suppressed UUO-induced macrophage infiltration and the expression of IL-6 in the obstructive kidneys. In NRK52E cells, fibrosis-related signaling was increased by TGFß1 and reduced by ß-OHB. ß-OHB treatment restored the impaired expression of Cpt1a. The effect of ß-OHB was blocked by siRNA targeting free fatty acid receptor 3 (FFAR3), suggesting that ß-OHB might function through the FFAR3-dependent pathway. Discussion: Our results highlight that KD attenuates UUO-induced renal fibrosis by enhancing FAO via the FFAR3-dependent pathway, which provides a promising dietary therapy for renal fibrosis.

16.
J Nutr Biochem ; 118: 109335, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37023933

RESUMEN

The ketogenic diet (KD), a high-fat and extremely low-carbohydrate dietary regimen, has long been acknowledged as a highly beneficial dietary therapy for the treatment of intractable epilepsy throughout the last decade. Because of its significant therapeutic potential for a variety of ailments, KD is increasingly attracting study interest. In renal fibrosis, KD has received little attention. This study aimed to determine whether KD protects against renal fibrosis in unilateral ureteral obstruction (UUO) models and the possible mechanisms. The ketogenic diet, according to our findings, reduces UUO-induced kidney injury and fibrosis in mice. KD dramatically decreased the number of F4/80+macrophages in kidneys. Next, immunofluorescence results revealed a reduction in the number of F4/80+Ki67+macrophages in the KD group. Furthermore, our study evaluated the impact of ß-hydroxybutyric acid (ß-OHB) in RAW246.7 macrophages in vitro. We found that ß-OHB inhibits macrophage proliferation. Mechanistically, ß-OHB inhibits macrophage proliferation may be via the FFAR3-AKT pathway. Collectively, our study indicated that KD ameliorates UUO-induced renal fibrosis by regulating macrophage proliferation. KD may be an effective therapy method for renal fibrosis due to its protective impact against the disorder.


Asunto(s)
Dieta Cetogénica , Enfermedades Renales , Obstrucción Ureteral , Ratones , Animales , Obstrucción Ureteral/complicaciones , Obstrucción Ureteral/tratamiento farmacológico , Obstrucción Ureteral/metabolismo , Enfermedades Renales/etiología , Riñón/metabolismo , Macrófagos/metabolismo , Fibrosis , Proliferación Celular , Ratones Endogámicos C57BL
17.
Biodivers Data J ; 11: e103580, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38327331

RESUMEN

Background: To date, 10 species of the genus Microhyla have been recorded in China, of which six were distributed in Yunnan Province. Microhylahmongorum Hoang, Nguyen, Phan, Pham, Ninh, Wang, Jiang, Ziegler, and Nguyen, 2022 was also speculated to be distributed in Xishuangbana, Yunnan Province, China. However, there is no evidence of documentation of M.hmongorum. New information: We report the first country record of Microhylahmongorum, based on specimens collected from Yunnan border region. Morphologically, the specimen was consistent with the original descriptions of M.hmongorum. Phylogenetically, the sequences of the specimens from China clustered with the sequence of type specimens of M.hmongorum from Vietnam, with uncorrected pairwise distances of 0.9% at the 16S gene fragment analysed. Therefore, we report M.hmongorum as a new record species in China.

18.
Front Immunol ; 13: 923424, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35874724

RESUMEN

Innate lymphoid cells (ILCs) develop from ILC progenitors in the bone marrow. Various ILC precursors (ILCPs) with different ILC subset lineage potentials have been identified based on the expression of cell surface markers and ILC-associated key transcription factor reporter genes. This study characterized an interleukin (IL)-7Rα+IL-18Rα+ ILC progenitor population in the mouse bone marrow with multi-ILC lineage potential on the clonal level. Single-cell gene expression analysis revealed the heterogeneity of this population and identified several subpopulations with specific ILC subset-biased gene expression profiles. The role of IL-18 signaling in the regulation of IL-18Rα+ ILC progenitors and ILC development was further investigated using Il18- and Il18r1-deficient mice, in vitro differentiation assay, and adoptive transfer model. IL-18/IL-18R-mediated signal was found to not be required for early stages of ILC development. While Il18r1-/- lymphoid progenitors were able to generate all ILC subsets in vitro and in vivo like the wild-type counterpart, increased IL-18 level, as often occurred during infection or under stress, suppressed the growth of ILCP/ILC in an IL-18Ra-dependent manner via inhibiting proliferation and inducing apoptosis.


Asunto(s)
Inmunidad Innata , Subunidad alfa del Receptor de Interleucina-18 , Interleucina-18 , Linfocitos , Animales , Diferenciación Celular , Interleucina-18/metabolismo , Subunidad alfa del Receptor de Interleucina-18/metabolismo , Linfocitos/metabolismo , Ratones , Análisis de la Célula Individual
19.
ACS Appl Mater Interfaces ; 14(41): 46401-46409, 2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36183270

RESUMEN

The regulation of the coordination environment of the central metal atom is considered as an alternative way to enhance the performance of single-atom catalysts (SACs). Herein, we design an electrocatalyst with active sites of isolated Co atoms coordinated with four sulfur atoms supported on N-doped carbon frameworks (Co1-S4/NC), confirmed by high-angle annular dark-field scanning transmission electron microscope (HADDF-STEM) and synchrotron-radiation-based X-ray absorption fine structure (XAFS) spectroscopy. The Co1-S4/NC possesses higher hydrogen evolution reaction (HER) catalytic activity than other Co species and exceptional stability, which exhibits a small Tafel slope of 60 mV dec-1 and a low overpotential of 114 mV at 10 mA cm-2 during the HER in 0.5 M H2SO4 solution. Furthermore, through in situ X-ray absorption spectrum tests and density functional theory (DFT) calculations, we reveal the catalytic mechanism of Co1-S4 moieties and find that the increasing number of sulfur atoms in the Co coordination environment leads to a substantial reduction of the theoretical HER overpotential. This work may point a new direction for the synthesis, performance regulation, and practical application of single-metal-atom catalysts.

20.
Zool Res ; 43(3): 469-480, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35514224

RESUMEN

Effective conservation of threatened biota relies on accurate assessments and scientific guidance. As an unfortunate example, Chinese giant salamanders ( Andrias, CGS) remain critically endangered in nature. Misguided conservation efforts, e.g., commercial propagation and releasing of millions of likely non-indigenous or interspecific hybrids, have further compromised conservation initiatives. Limited information on wild populations of CGS poses a significant conservation challenge. Following 18-month long field monitoring, we now report the discovery of a wild population of CGS in a closed nature reserve in Jiangxi Province, China. Genomic assessments reveal its genetic distinctiveness and do not detect genetic admixture with other species. Based on morphological and molecular evidences, we describe this CGS as a new species Andrias jiangxiensis sp. nov. This is the only known species of CGS today with a genetically pure, reproducing, in situ population. This discovery emphasizes the important role that closed nature reserves play in protecting species, and the necessity of integrating long-term field monitoring and genetic assessments. It sets a new pathway for discovering and conserving endangered species, especially for those biotas that are similarly being extirpated by anthropogenic translocations and overexploitation.


Asunto(s)
Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Animales , China , Urodelos/genética
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