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1.
Cell Mol Life Sci ; 81(1): 130, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472355

RESUMO

ALKBH1 is a typical demethylase of nucleic acids, which is correlated with multiple types of biological processes and human diseases. Recent studies are focused on the demethylation of ALKBH1, but little is known about its non-demethylase function. Here, we demonstrate that ALKBH1 regulates the glycolysis process through HIF-1α signaling in a demethylase-independent manner. We observed that depletion of ALKBH1 inhibits glycolysis flux and extracellular acidification, which is attributable to reduced HIF-1α protein levels, and it can be rescued by reintroducing HIF-1α. Mechanistically, ALKBH1 knockdown enhances chaperone-mediated autophagy (CMA)-mediated HIF-1α degradation by facilitating the interaction between HIF-1α and LAMP2A. Furthermore, we identify that ALKBH1 competitively binds to the OST48, resulting in compromised structural integrity of oligosaccharyltransferase (OST) complex and subsequent defective N-glycosylation of LAMPs, particularly LAMP2A. Abnormal glycosylation of LAMP2A disrupts lysosomal homeostasis and hinders the efficient degradation of HIF-1α through CMA. Moreover, NGI-1, a small-molecule inhibitor that selectively targets the OST complex, could inhibit the glycosylation of LAMPs caused by ALKBH1 silencing, leading to impaired CMA activity and disruption of lysosomal homeostasis. In conclusion, we have revealed a non-demethylation role of ALKBH1 in regulating N-glycosylation of LAMPs by interacting with OST subunits and CMA-mediated degradation of HIF-1α.


Assuntos
Autofagia , Transdução de Sinais , Humanos , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Glicosilação , Glicólise , Homólogo AlkB 1 da Histona H2a Dioxigenase/metabolismo
2.
Biol Reprod ; 110(1): 140-153, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-37812450

RESUMO

Fish have evolved various reproductive strategies including oviparity, viviparity, and ovoviviparity, which undoubtedly affect the survival of the whole species continuity. As the final step in reproduction, parturition in viviparous vertebrate and ovulation in oviparous teleost seem to share a similar mechanism, when prostaglandins (PGs) act as the trigger to launch the whole process. In the present study, ovoviviparous teleost black rockfish (Sebastes schlegelii) is employed as the research object. Intraperitoneal injection showed that PGE2 (500 µg/kg) could activate the delivery reactions in perinatal black rockfish. RNA-seq data of ovary in perinatal period revealed transcriptional change in cell junction, inflammation, and apoptosis, which is related to mammal parturition and teleost ovulation. Further results proved the positive correlation between ptger EP2 and previous mentioned pathways. Subsequent experiment proved that PGE2 was able to induce the ovulation and spawning in unfertilized individuals, which had a bilayer follicular structure compared to monolayer follicular in perinatal period black rockfish. Both unfertilized and perinatal ovary matrix could response to PGE2 stimulation. In conclusion, the function of PGE2 in activating both parturition and ovulation in a relatively different pathways conserved with viviparity or oviparity provided novel evidence of the evolutionary status of ovoviviparous vertebrates.


Assuntos
Ovoviviparidade , Perciformes , Animais , Feminino , Gravidez , Ovoviviparidade/genética , Dinoprostona , Sequência de Aminoácidos , Ovulação , Parto , Filogenia , Mamíferos
3.
Biol Reprod ; 109(5): 693-704, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37593921

RESUMO

Along with the evolution process, the reproductive strategies evolved including oviparity, viviparity and ovoviviparity, to fit the residential environment maximize the survival rate of the off spring. In mammals, the key to the initiation of parturition is the inflammatory response at the maternal-fetal interface. As a pro-inflammatory cytokine, interleukin 1 beta (IL1ß) plays an important role in the process of human parturition. While less is known about IL1ß1 in teleost parturition, identification of the functions of IL1ß1 in inducing the parturition, black rockfish, an ovoviviparity teleost, which provides over 60% nutrition supply for over 50 000 embryos though a placenta like structure during pregnant, was employed as the research model. In the present study, based on the gene cloning, we detected the expression pattern of both Il1b1 and its receptor perinatal period, as well as the localization to the ovary by in situ hybridization. The different expression genes in transcriptomic data of perinatal primary ovarian cells treated with the recombinant IL1ß1 (rIL1ß1) obtained by prokaryotic expression system were analyzed. Differentially expressed genes, functional enrichment and pathway analysis mainly included immune response, signal transduction and cell death. In summary, our research provides novel insights into the potential role of IL1ß1 in the parturition of ovoviviparity teleost.


Assuntos
Ovoviviparidade , Perciformes , Gravidez , Animais , Feminino , Humanos , Ovoviviparidade/fisiologia , Citocinas/genética , Sequência de Aminoácidos , Filogenia , Perciformes/genética , Parto , Proteínas de Peixes/genética , Proteínas de Peixes/química , Mamíferos
4.
Br J Nutr ; 130(12): 2039-2052, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-37183696

RESUMO

Iodine is an essential nutrient that may change the occurrence of autoimmune thyroiditis (AIT). Apoptosis and DNA methylation participate in the pathogenesis and destructive mechanism of AIT. We detected the methylation and the expression of mRNA of intrinsic apoptosis-associated genes (YWHAG, ING4, BRSK2 and GJA1) to identify the potential interactions between the levels of methylation in these genes and different levels of iodine. 176 adult patients with AIT in Shandong Province, China, were included. The MethylTargetTM assay was used to verify the levels of methylation. We used PCR to detect the mRNA levels of the candidate genes. Interactions between methylation levels of the candidate genes and iodine levels were evaluated with multiplicative and addictive interaction models and GMDR. In the AIT group, YWHAG_1 and six CpG sites and BRSK2_1 and eight CpG sites were hypermethylated, whereas ING4_1 and one CpG site were hypomethylated. A negative correlation was found between methylation levels of YWHAG and mRNA expression. The combination of iodine fortification, YWHAG_1 hypermethylation and BRSK2_1 hypermethylation was significantly associated with elevated AIT risk. A four-locus model (YWHAG_1 × ING4_1 × BRSK2_1 × iodine level) was found to be the best model of the gene-environment interactions. We identified abnormal changes in the methylation status of YWHAG, ING4 and BRSK2 in patients with AIT in different iodine levels. Iodine fortification not only affected the methylation levels of YWHAG and BRSK2 but also interacted with the methylation levels of these genes and may ultimately increase the risk of AIT.


Assuntos
Iodo , Tireoidite Autoimune , Adulto , Humanos , Tireoidite Autoimune/genética , Metilação de DNA , Iodo/metabolismo , Interação Gene-Ambiente , Apoptose/genética , RNA Mensageiro/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo
5.
Gen Comp Endocrinol ; 338: 114275, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36940835

RESUMO

To guarantee the quality and survival rate of their offspring, ovoviviparous teleost evolved special characteristics of in vivo fertilization and embryo development. Maternal black rockfish, having over 50 thousand embryos developing within the ovary simultaneously, provided around 40% nutrition throughout oocyte development, while the capillaries around each embryo contributed the rest 60% during pregnancy. Since fertilization, capillaries started to proliferate and developed into a placenta-like structure that covered over half of each embryo. Aimed to characterize the potential mechanism behind, comparative transcriptome analysis of samples collected according to the process of pregnancy. Three important time point in the process, including mature oocyte stage, fertilization and sarcomere period, were chosen for the transcriptome sequencing. Our study identified key pathways and genes involved in the cell cycle as well as DNA replication and repair, cell migration and adhesion, immune, and metabolic functions. Notably, several of the semaphoring gene family members were differently expressed. To confirm the accuracy of these genes, total of 32 sema genes were identified from the whole genome and distinct expression pattern of sema genes was observed in different pregnant stages. Our results revealed a novel insight for further investigating the functions of sema genes in reproduction physiology and embryo processes in ovoviviparous teleost.


Assuntos
Perciformes , Transcriptoma , Animais , Feminino , Ovoviviparidade/fisiologia , Perciformes/genética , Ovário/metabolismo , Perfilação da Expressão Gênica , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo
6.
Opt Express ; 30(2): 2063-2077, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209354

RESUMO

The optical scale bar with calibrated or measured internal point-to-point length has many applications in coordinate measurements. In this paper, the virtual optical scale bar with two retroreflectors is constructed by the absolute distance measurement based on pulse-to-pulse interferometry. The temporal and dispersive coherence could be utilized to determine the adjustable internal length of multiple pulse-to-pulse intervals with high precision. The proposed scheme was combined with a pellicle beamsplitter to minimize systematic error. The influence of its thickness on precision is also discussed and calibrated in detail. Besides, a femtosecond mode-locked pulse laser with 100-MHz repetition rates was employed in our system to develop an optical scale bar and verify the feasibility of the proposed method. The sub-micron precision could be realized by temporal coherence with a piezo-driven stage or a simplified non-polarized scheme of dispersed coherence. It shows that this method could achieve a flexible and high-precision virtual optical scale bar for further practical applications.

7.
FASEB J ; 35(10): e21908, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34478580

RESUMO

Cadherin EGF LAG seven-pass G-type receptor 2 (CELSR2), a mammalian orthologue of drosophila flamingo, belongs to the cadherin subfamily. CELSR2 mainly function in neural development and cilium polarity. Recent studies showed that the CELSR2 gene is related to many human diseases, including coronary artery disease, idiopathic scoliosis, and cancer. Genome-Wide Association Studies data showed that SNP in the CELSR2-PSRC1-SORT1 gene loci has a strong association with circulating lipid levels and coronary artery disease. However, the function and underlying mechanism of CELSR2 in hepatic lipid metabolism remain unknown. Here, we found that CELSR2 expression is decreased in the liver of NAFLD/NASH patients and db/db mice. Depletion of CELSR2 significantly decreased the lipid accumulation in hepatocytes by suppressing the expression of lipid synthesis enzymes. Moreover, CELSR2 deficiency impaired the physiological unfolded protein response (UPR), which damages the ER homeostasis, and elevates the reactive oxygen species (ROS) level by decreasing the antioxidant expression. Scavenging of ROS by N-acetylcysteine treatment could restore the decreased lipid accumulation of CELSR2 knockdown cells. Furthermore, CELSR2 loss impaired cell survival by suppressing cell proliferation and promoting apoptosis. Our results uncovered a new role of CELSR2 in regulating lipid homeostasis and UPR, suggesting CELSR2 may be a new therapeutic target for non-alcoholic fatty liver disease.


Assuntos
Caderinas/deficiência , Hepatócitos/metabolismo , Metabolismo dos Lipídeos , Espécies Reativas de Oxigênio/metabolismo , Resposta a Proteínas não Dobradas , Animais , Apoptose/genética , Caderinas/genética , Linhagem Celular , Proliferação de Células/genética , Sobrevivência Celular/genética , Hepatócitos/enzimologia , Humanos , Lipídeos , Masculino , Camundongos , Resposta a Proteínas não Dobradas/genética
8.
Br J Nutr ; : 1-11, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35876046

RESUMO

The aim of this study was to explore the status of thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TGAb) in three areas with differing water iodine concentrations; and to discuss the relationships between these two thyroid antibodies and thyroid diseases in the three areas. We investigated 2503 adults from three areas. Urinary iodine concentrations, thyroid stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), TPOAb, TGAb and thyroid volume (TV) were measured, and thyroid ultrasonography was performed. The positivity rates of TGAb(+), TPOAb(+) and TGAb(+) and TPOAb(+) or TGAb(+) were significantly higher in iodine fortification (IF) areas than iodine adequate (IA) areas (all P < 0·05). In IF and iodine excess areas, the positivity rates of TPOAb(+), TGAb(+) and TPOAb(+) or TGAb(+) significantly increased with age (all P for trend < 0·05). The levels of TSH, TV and the prevalence of overt hypothyroidism, subclinical hypothyroidism and goitre were significantly elevated in the thyroid antibody-positive groups in the three areas, but the FT3 was diminished (all P < 0·010). Positivity for TPOAb and TGAb was associated with an increased risk of subclinical hypothyroidism in the three areas. In areas with different median water iodine, positivity for both TPOAb and TGAb was associated with elevated TSH values. Notably, with the increased levels of TPOAb, the frequency of abnormally elevated TSH increased dramatically in the three areas.

9.
Gen Comp Endocrinol ; 316: 113947, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34848189

RESUMO

Glucocorticoid receptors (GRs) are ligand-activated transcription factors associated with anti-inflammation, stress, metabolism and gonadal development. In this study, two gr genes (gr1 and gr2) were cloned and analyzed from a viviparous teleost, black rockfish (Sebastes schlegelii). The phylogenetic analysis of GRs showed that GR1 and GR2 clustered into teleost GR1 and GR2 separately and differed from the GRs of tetrapods or basal ray-finned fishes. Black rockfish GRs possess four modular domains of the nuclear receptor superfamily: an N-terminal domain (NTD), a DNA-binding domain (DBD), a hinge region (HR) and a ligand-binding domain (LBD). Nine conserved amino acid inserts were found in the GR1 DBD, and the ligand cavity-related amino acids of GR1 and GR2 LBD were slightly different. Tissue distribution analysis revealed that grs was widely expressed in various tissues, while cyp11b was mainly expressed in the testis and head kidney. The cyp11b transcripts were localized in the interrenal glands of the head kidney, the main source of cortisol; grs transcripts were detected in oocytes, the follicle layer and the ovarian wall. Histologically, significant blood vessel dilation was observed in the fetal membrane during or after parturition of black rockfish. The highest levels of serum cortisol and ovarian cyp11b mRNA were detected in parturition. In addition, the relative expression level of gr1 was upregulated significantly after delivery, while the levels of gr2 showed no significant change. In addition, in vitro GC treatment inhibited the expression of il1b but significantly upregulated the transcription of il1r1. These data provide evidence that GRs are likely to work as anti-inflammatory factors by inhibiting the functions of pro-inflammatory factors in the parturition of black rockfish.


Assuntos
Perciformes , Receptores de Glucocorticoides , Animais , Proteínas de Peixes/metabolismo , Peixes/genética , Peixes/metabolismo , Gônadas/metabolismo , Masculino , Perciformes/genética , Perciformes/metabolismo , Filogenia , Receptores de Glucocorticoides/metabolismo
10.
Proc Natl Acad Sci U S A ; 116(14): 6932-6937, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30894497

RESUMO

Clinical application of inhaled glucocorticoids (GCs) has been hampered in the case of steroid-resistant severe asthma. To overcome this limitation, we have developed a series of highly potent GCs, including VSGC12, VSG158, and VSG159 based on the structural insight into the glucocorticoid receptor (GR). Particularly, VSG158 exhibits a maximal repression of lung inflammation and is 10 times more potent than the currently most potent clinical GC, Fluticasone Furoate (FF), in a murine model of asthma. More importantly, VSG158 displays a unique property to reduce neutrophilic inflammation in a steroid-resistant airway inflammation model, which is refractory to clinically available GCs, including dexamethasone and FF. VSG158 and VSG159 are able to deliver effective treatments with reduced off-target and side effects. In addition, these GCs also display pharmacokinetic properties that are suitable for the inhalation delivery method for asthma treatment. Taken together, the excellent therapeutic and side-effect profile of these highly potent GCs holds promise for treating steroid-resistant severe asthma.


Assuntos
Antiasmáticos , Asma/tratamento farmacológico , Desenvolvimento de Medicamentos , Glucocorticoides , Animais , Antiasmáticos/química , Antiasmáticos/farmacologia , Asma/patologia , Modelos Animais de Doenças , Feminino , Glucocorticoides/química , Glucocorticoides/farmacologia , Masculino , Camundongos , Receptores de Glucocorticoides/agonistas , Índice de Gravidade de Doença
11.
BMC Genomics ; 22(1): 874, 2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34863110

RESUMO

BACKGROUND: The black rockfish (Sebastes schlegelii) has an ovoviviparous reproductive pattern and long-term sperm storage, resulting in asynchronous gonadal development between the sexes. However, the comprehensive understanding of gonadal development in black rockfish has not yet been achieved. Here, we studied gonadal development and germ cell renewal using histology and RNA-seq. RESULTS: In this study, RNA-seq was performed on testes and ovaries to characterize key pathways and genes that are active during development and gamete maturation in black rockfish. Differentially expressed genes (DEGs) were identified and annotated in 4 comparisons (F_III vs. F_IV, F_IV vs. F_V, M_III vs. M_IV and M_IV vs. M_V). Based on analysis of DEGs enriched in the testis, 11 and 14 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were mapped to the M_III vs. M_IV group and the M_IV vs. M_V group, respectively. DEGs in ovarian development were also classified into 10 groups according to their biological functions. The expression patterns of the selected genes determined by qPCR were significantly correlated with the RNA-Seq results, supporting the reliability and accuracy of the RNA-Seq analysis. E2 levels showed down regulation from previtellogenesis to mature stage in female and T level showed down regulation from spermatogenesis to regressed stage in the male. CONCLUSIONS: The categories "intercellular interaction and cytoskeleton", "molecule amplification" and "repair in the cell cycle" were revealed to be crucial in testis development and spermatogenesis, as was the biosynthesis of a series of metabolites. Our results provide comprehensive insight into black rockfish gonadal development and provide a basis for further study of reproductive physiology and molecular biology in ovoviviparity teleosts.


Assuntos
Ovoviviparidade , Perciformes , Animais , Feminino , Gônadas , Masculino , Reprodutibilidade dos Testes , Transcriptoma
12.
Gen Comp Endocrinol ; 302: 113689, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33301756

RESUMO

Mitochondrial cytochrome P450 side-chain cleavage (P450scc), encoded by the cyp11a1 gene, initiates the first step of steroid biosynthesis. In this study, a 1554-bp open reading frame (ORF) of black rockfish (Sebastes schlegelii) cyp11a1 was cloned. The cyp11a1 gene is located on chromosome 5 and has 9 exons. The ORF encodes a putative precursor protein of 517 amino acids, and the predicted cleavable mitochondrial targeting peptide is located at amino acids 1-39. P450scc shares homology with other teleosts and tetrapods, which have relatively conserved binding regions with heme, cholesterol and adrenodoxin. Tissue distribution analysis revealed that the highest expression levels of cyp11a1 were detected in mature gonads and head kidney but that low levels were detected in gestational/regressed ovaries, regressed testes and other tissues. Immunostaining of P450scc was observed in testicular Leydig cells, ovarian theca cells, interrenal glands of head kidney, pituitary and multiple regions of brain. Particularly, two kinds of fish-specific P450scc-positive cells, including coronet cells of brain saccus vasculosus and hypophyseal somatolactin cells, were identified in black rockfish. Our results provide novel evidence for the potential role played by P450scc in reproduction behavior by mediating steroidogenesis in viviparous teleost.


Assuntos
Enzima de Clivagem da Cadeia Lateral do Colesterol , Perciformes , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Feminino , Peixes/genética , Gônadas , Masculino , Perciformes/genética , Desenvolvimento Sexual
13.
Fish Physiol Biochem ; 47(4): 811-828, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33694040

RESUMO

In order to study the variation of gonad lipidomics during reproductive cycle, black rockfish was employed as the research model in the present study. Using histology, lipidomics, and qPCR, the profile of gonad lipidomics and the expression levels of related genes during different developmental stages were detected and analyzed to show the potential regulatory network of lipid metabolism. Based on Ultra High-Performance Liquid Tandem Chromatography Quadrupole Time of Flight Mass Spectrometry (UHPLC-QTOFMS), four significant differential glycerophospholipid metabolic pathways including phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), and phosphatidic acid (PA) were enriched by KEGG. Pathway-related enzyme-coding genes, including phosphatidylserine decarboxylase (pisd), phosphatidylserine synthase (ptdss1, ptdss2), and phospholipase D (pld1, pld2) were identified from the whole genome data and confirmed by cloning. The expression profiles of these genes were tested by qPCR in the tissues and gonads in developmental stages, and we found that pisd, pld, and ptdss genes were all downregulated through the developmental process in the brain of male, and the latter two genes were upregulated in the liver and testis at stage IV, which were the opposite trend observed in the female. Thus, our findings would be helpful in further understanding the substance metabolism and regulation during gonad development in ovoviviparity teleosts.


Assuntos
Glicerofosfolipídeos/metabolismo , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Perciformes , Testículo/crescimento & desenvolvimento , Testículo/metabolismo , Animais , Feminino , Expressão Gênica , Lipidômica , Masculino , Ovoviviparidade/genética , Perciformes/genética , Perciformes/crescimento & desenvolvimento , Perciformes/metabolismo , Filogenia
14.
Opt Express ; 28(4): 4398-4411, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32121677

RESUMO

In this paper, we propose a method aiming to measure the absolute distance via the slope of the inter-mode beat phase by sweeping the repetition frequency of the frequency comb. The presented approach breaks the inertial thinking of the extremely stable comb spacing, and the bulky phase-locking circuit of the repetition frequency is not required. In particular, the non-ambiguity range can be expanded to be infinite. To verify the performance of presented method, a series of distance experiments have been devised in different scenarios. Compared with the reference values, the experimental results show the differences within 25 µm at 65 m range in the laboratory, and within 100 µm at 219 m range out of the lab.

15.
Hum Mol Genet ; 26(15): 2949-2960, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28486600

RESUMO

Ciliopathies form a group of inherited disorders sharing several clinical manifestations because of abnormal cilia formation or function, and few treatments have been successful against these disorders. Here, we report a mouse model with mutated Sclt1 gene, which encodes a centriole distal appendage protein important for ciliogenesis. Sodium channel and clathrin linker 1 (SCLT1) mutations were associated with the oral-facial-digital syndrome (OFD), an autosomal recessive ciliopathy. The Sclt1-/- mice exhibit typical ciliopathy phenotypes, including cystic kidney, cleft palate and polydactyly. Sclt1-loss decreases the number of cilia in kidney; increases proliferation and apoptosis of renal tubule epithelial cells; elevates protein kinase A, extracellular signal-regulated kinases, SMAD and signal transducer and activator of transcription 3 (STAT3) pathways; and enhances pro-inflammation and pro-fibrosis pathways with disease progression. Embryonic kidney cyst formation of Sclt1-/- mice was effectively reduced by an anti-STAT3 treatment using pyrimethamine. Overall, we reported a new mouse model for the OFD; and our data suggest that STAT3 inhibition may be a promising treatment for SCLT1-associated cystic kidney.


Assuntos
Fator de Transcrição STAT3/metabolismo , Canais de Sódio/metabolismo , Animais , Cílios/metabolismo , Ciliopatias/genética , Ciliopatias/metabolismo , Cistos/metabolismo , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Rim/metabolismo , Doenças Renais Císticas/etiologia , Doenças Renais Císticas/genética , Doenças Renais Císticas/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Transgênicos , Modelos Animais , Mutação , Fenótipo , Fator de Transcrição STAT3/genética , Transdução de Sinais , Canais de Sódio/genética
16.
J Lipid Res ; 59(10): 1841-1850, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30087205

RESUMO

Intestinal alkaline SMase (Alk-SMase) cleaves phosphocholine from SM, platelet-activating factor (PAF), and lysophosphatidylcholine. We recently found that colitis-associated colon cancer was 4- to 5-fold enhanced in Alk-SMase KO mice. Here, we further studied the pathogenesis of colitis induced by dextran sulfate sodium (DSS) in WT and KO mice. Compared with WT mice, KO mice demonstrated greater body weight loss, more severe bloody diarrhea, broader inflammatory cell infiltration, and more serious epithelial injury. Higher levels of PAF and lower levels of interleukin (IL)10 were identified in KO mice 2 days after DSS treatment. A greater and progressive increase of lysophosphatidic acid (LPA) was identified. The change was associated with increased autotaxin expression in both small intestine and colon, which was identified by immunohistochemistry study, Western blot, and sandwich ELISA. The upregulation of autotaxin coincided with an early increase of PAF. IL6 and TNFα were increased in both WT and KO mice. At the later stage (day 8), significant decreases in IL6, IL10, and PAF were identified, and the decreases were greater in KO mice. In conclusion, deficiency of Alk-SMase enhances DSS-induced colitis by mechanisms related to increased autotaxin expression and LPA formation. The early increase of PAF might be a trigger for such reactions.


Assuntos
Colite/induzido quimicamente , Colite/metabolismo , Sulfato de Dextrana/efeitos adversos , Diester Fosfórico Hidrolases/metabolismo , Esfingomielina Fosfodiesterase/deficiência , Esfingomielina Fosfodiesterase/genética , Regulação para Cima/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/genética , Proteínas de Transporte/biossíntese , Colite/enzimologia , Colite/genética , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Técnicas de Inativação de Genes , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Lisofosfolipídeos/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Fator de Necrose Tumoral alfa/metabolismo
17.
Biochim Biophys Acta Mol Basis Dis ; 1864(2): 338-346, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29101051

RESUMO

Hepatic insulin sensitivity is critical for glucose homeostasis, and insulin resistance is a fundamental syndrome found in various metabolic disorders, including obesity and type 2 diabetes. Despite considerable studies on the mechanisms of hepatic insulin resistance, the link between epigenetic regulation and the development of insulin resistance remains elusive. Here, we reported that G9a/EHMT2, a histone methyltransferase, was markedly decreased in the liver of db/db mice and high-fat diet (HFD)-fed mice. In cultured hepatic cells, G9a knockdown resulted in downregulation of insulin receptor, p-AKT and p-GSK3ß; while upon upregulation, G9a prevented the palmitic acid- or glucosamine-induced insulin resistance by preserving the normal level of insulin receptor and integrity of insulin signaling. Further mechanistic study suggested that G9a regulated the expression level of high mobility group AT-hook 1 (HMGA1), a key regulator responsible for the transcription of insulin receptor (INSR) gene. Overexpression of HMGA1 normalized the impaired insulin signaling in G9a knockdown hepatic cells. Importantly, in db/db mice, restoring the expression level of G9a not only upregulated HMGA1 level and improved the impaired hepatic insulin signaling, but also alleviated hyperglycemia and hyperinsulinemia. Together, our results revealed a novel role for G9a in modulating insulin signaling, at least in part, depending on its regulatory function on HMGA1.


Assuntos
Proteína HMGA1a/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Resistência à Insulina , Insulina/metabolismo , Fígado/metabolismo , Animais , Glicemia/análise , Dieta Hiperlipídica , Epigênese Genética , Regulação da Expressão Gênica , Glucosamina/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Células Hep G2 , Antígenos de Histocompatibilidade/genética , Histona-Lisina N-Metiltransferase/genética , Histonas/metabolismo , Humanos , Insulina/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ácido Palmítico/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor de Insulina/metabolismo , Receptores para Leptina/genética , Transdução de Sinais
18.
Hepatology ; 66(2): 631-645, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28387968

RESUMO

Up-regulated glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is observed in multiple cancers with unclear mechanism. Using GAPDH transgenic mouse and a mouse model of diethylnitrosamine-induced hepatocellular carcinoma (HCC), here we show that GAPDH overexpression aggravated tumor development by activating cell proliferation and inflammation. In cultured hepatic cells, overexpression of GAPDH or a catalytic domain-deleted GAPDH (GAPDHΔCD ) affected metabolism, up-regulated phosphoglycerate dehydrogenase (PHGDH), increased histone methylation levels, and promoted proliferation. Consistently, inhibition of GAPDH by short hairpin RNA reprogrammed metabolism down-regulated PHGDH and histone methylation, and inhibited proliferation. The xenograft study suggested that HepG2 cells overexpressing GAPDH or GAPDHΔCD similarly promoted tumor development, whereas knockdown PHGDH in GAPDH overexpressing cells significantly inhibited tumor development. In liver sections of HCC patients, increased GAPDH staining was found to be positively correlated with PHGDH and histone methylation staining. CONCLUSION: GAPDH increases histone methylation levels by up-regulating PHGDH, promoting diversion from glycolysis to serine biosynthesis, and consequently accelerating HCC development. (Hepatology 2017;66:631-645).


Assuntos
Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Neoplasias Hepáticas/genética , Fosfoglicerato Desidrogenase/genética , Animais , Biópsia por Agulha , Western Blotting , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , Modelos Animais de Doenças , Regulação para Baixo , Imuno-Histoquímica , Modelos Lineares , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias Experimentais , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Estatísticas não Paramétricas , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
19.
J Am Soc Nephrol ; 28(9): 2694-2707, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28583915

RESUMO

Renal ischemia-reperfusion (I/R) injury is the most common cause of AKI, which associates with high mortality and has no effective therapy. ELABELA (ELA) is a newly identified 32-residue hormone peptide highly expressed in adult kidney. To investigate whether ELA has protective effects on renal I/R injury, we administered the mature peptide (ELA32) or the 11-residue furin-cleaved fragment (ELA11) to hypoxia-reperfusion (H/R)-injured or adriamycin-treated renal tubular cells in vitro ELA32 and ELA11 significantly inhibited the elevation of the DNA damage response, apoptosis, and inflammation in H/R-injured renal tubular cells and suppressed adriamycin-induced DNA damage response. Similarly, overexpression of ELA32 or ELA11 significantly inhibited H/R-induced cell death, DNA damage response, and inflammation. Notably, treatment of mice with ELA32 or ELA11 but not an ELA11 mutant with a cysteine to alanine substitution at the N terminus (AE11C) inhibited I/R injury-induced renal fibrosis, inflammation, apoptosis, and the DNA damage response and markedly reduced the renal tubular lesions and renal dysfunction. Together, our results suggest that ELA32 and ELA11 may be therapeutic candidates for treating AKI.


Assuntos
Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/prevenção & controle , Proteínas de Transporte/farmacologia , Fragmentos de Peptídeos/farmacologia , Hormônios Peptídicos/farmacologia , RNA Mensageiro/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Injúria Renal Aguda/genética , Injúria Renal Aguda/fisiopatologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Autofagia/efeitos dos fármacos , Proteínas de Transporte/genética , Proteínas de Transporte/uso terapêutico , Moléculas de Adesão Celular/genética , Hipóxia Celular , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quinase 1 do Ponto de Checagem/metabolismo , Reparo do DNA/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Receptor Celular 1 do Vírus da Hepatite A/genética , Histonas/metabolismo , Humanos , Inflamação/genética , Inflamação/prevenção & controle , Molécula 1 de Adesão Intercelular/genética , Interleucina-6/genética , Túbulos Renais/citologia , Camundongos , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/uso terapêutico , Hormônios Peptídicos/uso terapêutico , Fosfoproteínas/metabolismo , Fosforilação , Ratos , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/fisiopatologia , Fator de Crescimento Transformador beta1/genética , Fator de Necrose Tumoral alfa/genética
20.
Opt Express ; 24(21): 24361-24376, 2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27828166

RESUMO

Two-color interferometry is powerful for the correction of the air refractive index especially in the turbulent air over long distance, since the empirical equations could introduce considerable measurement uncertainty if the environmental parameters cannot be measured with sufficient precision. In this paper, we demonstrate a method for absolute distance measurement with high-accuracy correction of air refractive index using two-color dispersive interferometry. The distances corresponding to the two wavelengths can be measured via the spectrograms captured by a CCD camera pair in real time. In the long-term experiment of the correction of air refractive index, the experimental results show a standard deviation of 3.3 × 10-8 for 12-h continuous measurement without the precise knowledge of the environmental conditions, while the variation of the air refractive index is about 2 × 10-6. In the case of absolute distance measurement, the comparison with the fringe counting interferometer shows an agreement within 2.5 µm in 12 m range.

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