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1.
Acta Pharm Sin B ; 14(4): 1711-1725, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38572109

RESUMEN

Drug repurposing offers an efficient approach to therapeutic development. In this study, our bioinformatic analysis first predicted an association between obesity and lansoprazole (LPZ), a commonly prescribed drug for gastrointestinal ulcers. We went on to show that LPZ treatment increased energy expenditure and alleviated the high-fat diet-induced obesity, insulin resistance, and hepatic steatosis in mice. Treatment with LPZ elicited thermogenic gene expression and mitochondrial respiration in primary adipocytes, and induced cold tolerance in cold-exposed mice, suggesting the activity of LPZ in promoting adipose thermogenesis and energy metabolism. Mechanistically, LPZ is an efficient inhibitor of adipose phosphocholine phosphatase 1 (PHOSPHO1) and produces metabolic benefits in a PHOSPHO1-dependent manner. Our results suggested that LPZ may stimulate adipose thermogenesis by inhibiting the conversion of 2-arachidonoylglycerol-lysophosphatidic acid (2-AG-LPA) to 2-arachidonoylglycerol (2-AG) and reduce the activity of the thermogenic-suppressive cannabinoid receptor signaling. In summary, we have uncovered a novel therapeutic indication and mechanism of LPZ in managing obesity and its related metabolic syndrome, and identified a potential metabolic basis by which LPZ improves energy metabolism.

2.
Lancet Infect Dis ; 24(4): e212, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38340737
3.
Front Immunol ; 14: 1145080, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37180167

RESUMEN

Background: The role of copper in cancer treatment is multifaceted, with copper homeostasis-related genes associated with both breast cancer prognosis and chemotherapy resistance. Interestingly, both elimination and overload of copper have been reported to have therapeutic potential in cancer treatment. Despite these findings, the exact relationship between copper homeostasis and cancer development remains unclear, and further investigation is needed to clarify this complexity. Methods: The pan-cancer gene expression and immune infiltration analysis were performed using the Cancer Genome Atlas Program (TCGA) dataset. The R software packages were employed to analyze the expression and mutation status of breast cancer samples. After constructing a prognosis model to separate breast cancer samples by LASSO-Cox regression, we examined the immune statement, survival status, drug sensitivity and metabolic characteristics of the high- and low-copper related genes scoring groups. We also studied the expression of the constructed genes using the human protein atlas database and analyzed their related pathways. Finally, copper staining was performed with the clinical sample to investigate the distribution of copper in breast cancer tissue and paracancerous tissue. Results: Pan-cancer analysis showed that copper-related genes are associated with breast cancer, and the immune infiltration profile of breast cancer samples is significantly different from that of other cancers. The essential copper-related genes of LASSO-Cox regression were ATP7B (ATPase Copper Transporting Beta) and DLAT (Dihydrolipoamide S-Acetyltransferase), whose associated genes were enriched in the cell cycle pathway. The low-copper related genes scoring group presented higher levels of immune activation, better probabilities of survival, enrichment in pathways related to pyruvate metabolism and apoptosis, and higher sensitivity to chemotherapy drugs. Immunohistochemistry staining showed high protein expression of ATP7B and DLAT in breast cancer samples. The copper staining showed copper distribution in breast cancer tissue. Conclusion: This study displayed the potential impacts of copper-related genes on the overall survival, immune infiltration, drug sensitivity and metabolic profile of breast cancer, which could predict patients' survival and tumor statement. These findings may serve to support future research efforts aiming at improving the management of breast cancer.


Asunto(s)
Neoplasias de la Mama , ATPasas Transportadoras de Cobre , Cobre , Acetiltransferasa de Residuos Dihidrolipoil-Lisina , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Humanos , Cobre/análisis , Cobre/metabolismo , Perfilación de la Expresión Génica , Análisis de Supervivencia , ATPasas Transportadoras de Cobre/análisis , ATPasas Transportadoras de Cobre/genética , Acetiltransferasa de Residuos Dihidrolipoil-Lisina/análisis , Acetiltransferasa de Residuos Dihidrolipoil-Lisina/genética , Acetiltransferasa de Residuos Dihidrolipoil-Lisina/metabolismo , Pronóstico , Resistencia a Antineoplásicos , Modelos Biológicos
4.
Commun Biol ; 6(1): 194, 2023 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-36804628

RESUMEN

Hepatic ischemia-reperfusion (I/R) injury is a common complication in liver transplantation. The connection between I/R-induced injury response and liver heterogeneity has yet to be fully understood. In this study, we converge histopathological examination with spatial transcriptomics to dissect I/R injury patterns and their associated molecular changes, which reveal that the pericentral zones are most sensitive to I/R injury in terms of histology, transcriptomic changes, and cell type dynamics. Bioinformatic analysis of I/R injury-related pathways predicts that celastrol can protect against liver I/R injury by inducing ischemic pre-conditioning, which is experimentally validated. Mechanistically, celastrol likely implements its protective effect against I/R injury by activating HIF1α signaling and represents a potential strategy for resolving liver I/R.


Asunto(s)
Daño por Reperfusión , Transcriptoma , Ratones , Animales , Modelos Animales de Enfermedad , Hígado/metabolismo , Daño por Reperfusión/genética , Daño por Reperfusión/patología
5.
Proc Natl Acad Sci U S A ; 119(45): e2204795119, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36322719

RESUMEN

Abnormal neovascularization is an important cause of blindness in many ocular diseases, for which the etiology and pathogenic mechanisms remain incompletely understood. Recent studies have revealed the diverse roles of noncoding RNAs in various biological processes and facilitated the research and development of the clinical application of numerous RNA drugs, including microRNAs. Here, we report the antiangiogenic activity of microRNA-29a (miR-29a) in three animal models of ocular neovascularization. The miR-29a knockout (KO) mice displayed enhanced vessel pruning, resulting in a decreased vascularized area during retinal development. In contrast, miR-29a deletion in adult mice accelerated angiogenesis in preclinical disease models, including corneal neovascularization, oxygen-induced retinopathy, and choroidal neovascularization, while the administration of agomir-29a ameliorated pathological neovascularization. Furthermore, miR-29a exerted inhibitory effects on endothelial cell proliferation, migration, and tube formation capacities. RNA sequencing analysis of retinas from miR-29a KO mice and RNA interference experiments identified platelet-derived growth factor C and several extracellular matrix genes as downstream targets of miR-29a involved in regulating ocular angiogenesis. Our data suggest that miR-29a may be a promising clinical candidate for the treatment of neovascular diseases.


Asunto(s)
Neovascularización Coroidal , MicroARNs , Ratones , Animales , MicroARNs/metabolismo , Proliferación Celular , Interferencia de ARN , Ojo/metabolismo , Neovascularización Coroidal/metabolismo , Ratones Noqueados
6.
Front Physiol ; 13: 935195, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35957983

RESUMEN

Emerging evidence suggests that phosphoethanolamine/phosphocholine phosphatase 1 (PHOSPHO1), a specific phosphoethanolamine and phosphocholine phosphatase, is involved in energy metabolism. In this review, we describe the structure and regulation of PHOSPHO1, as well as current knowledge about the role of PHOSPHO1 and its related phospholipid metabolites in regulating energy metabolism. We also examine mechanistic evidence of PHOSPHO1- and phospholipid-mediated regulation of mitochondrial and lipid droplets functions in the context of metabolic homeostasis, which could be potentially targeted for treating metabolic disorders.

7.
J Virol ; 96(8): e0202821, 2022 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-35389233

RESUMEN

BK polyomavirus (PyV) infects the genitourinary tract of >90% of the adult population. Immunosuppression increases the risk of viral reactivation, making BKPyV a leading cause of graft failure in kidney transplant recipients. Polyomaviruses have a small double-stranded DNA (dsDNA) genome that requires host replication machinery to amplify the viral genome. Specifically, polyomaviruses promote S phase entry and delay S phase exit by activating the DNA damage response (DDR) pathway via an uncharacterized mechanism requiring viral replication. BKPyV infection elevates expression of MutSα, a mismatch repair (MMR) pathway protein complex that senses and repairs DNA mismatches and can activate the DDR. Thus, we investigated the role of the MMR pathway by silencing the MutSα component, Msh6, in BKPyV-infected primary cells. This resulted in severe DNA damage that correlated with weak DNA damage response activation and a failure to arrest the cell cycle to prevent mitotic entry during infection. Furthermore, silencing Msh6 expression resulted in significantly fewer infectious viral particles due to significantly lower levels of VP2, a minor capsid protein important for trafficking during subsequent infections. Since viral assembly occurs in the nucleus, our findings are consistent with a model in which entry into mitosis disrupts viral assembly due to nuclear envelope breakdown, which disperses VP2 throughout the cell, reducing its availability for encapsidation into viral particles. Thus, the MMR pathway may be required to activate the ATR (ATM-Rad3-related) pathway during infection to maintain a favorable environment for both viral replication and assembly. IMPORTANCE Since there are no therapeutics that target BKPyV reactivation in organ transplant patients, it is currently treated by decreasing immunosuppression to allow the natural immune system to fight the viral infection. Antivirals would significantly improve patient outcomes since reducing immunosuppression carries the risk of graft failure. PyVs activate the DDR, for which there are several promising inhibitors. However, a better understanding of how PyVs activate the DDR and what role the DDR plays during infection is needed. Here, we show that a component of the mismatch repair pathway is required for DDR activation during PyV infection. These findings show that the mismatch repair pathway is important for DDR activation during PyV infection and that inhibiting the DDR reduces viral titers by generating less infectious virions that lack the minor capsid protein VP2, which is important for viral trafficking.


Asunto(s)
Virus BK , Reparación de la Incompatibilidad de ADN , Virus BK/genética , Proteínas de la Cápside/genética , Daño del ADN , Reparación de la Incompatibilidad de ADN/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Humanos , Infecciones por Polyomavirus/virología , Replicación Viral/genética
8.
Molecules ; 26(22)2021 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-34833997

RESUMEN

The soft rot disease caused by Rhizopus stolonifer is an important disease in cherry tomato fruit. In this study, the effect of iturin A on soft rot of cherry tomato and its influence on the storage quality of cherry tomato fruit were investigated. The results showed that 512 µg/mL of iturin A could effectively inhibit the incidence of soft rot of cherry tomato fruit. It was found that iturin A could induce the activity of resistance-related enzymes including phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), peroxidase (POD), glucanase (GLU), and chitinase (CHI), and active oxygen-related enzymes including ascorbate peroxidases (APX), superoxide dismutases (SOD), catalases (CAT), and glutathione reductase (GR) of cherry tomato fruit. In addition, iturin A treatment could slow down the weight loss of cherry tomato and soften the fruit. These results indicated that iturin A could retard the decay and improve the quality of cherry tomato fruit by both the inhibition growth of R. stolonifera and the inducing the resistance.


Asunto(s)
Resistencia a Medicamentos/efectos de los fármacos , Frutas/metabolismo , Péptidos Cíclicos/farmacología , Enfermedades de las Plantas/microbiología , Raíces de Plantas/metabolismo , Solanum lycopersicum/metabolismo , Frutas/microbiología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Solanum lycopersicum/microbiología , Proteínas de Plantas/biosíntesis , Raíces de Plantas/microbiología , Rhizopus/crecimiento & desarrollo
9.
Ocul Immunol Inflamm ; 29(6): 1045-1055, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-32657648

RESUMEN

Purpose: To characterize the quality of life and mental health status of patients with uveitis and investigate predictors of psychological problems.Methods: A total of 245 patients and 105 controls were enrolled in this cross-sectional study. Quality of life, psychological status, socio-demographic and clinical data were obtained from questionnaires and medical records. Multivariate regression analyses and Receiver Operating Characteristic (ROC) were applied to obtain the model predicting psychological problems of patients.Results: Of 245 patients, 16.7% and 26.5% (P< .0001) screened positive for anxiety and depression, respectively. The model predicting anxiety was comprised of low annual household income and poor self-reported visual function (P= .029,P< .0001, respectively), with an AUC of ROC of 0.744. The model predicting depression was comprised of poor self-reported visual function and ocular complications (P< .0001, P= .012, respectively), with an AUC of 0.78.Conclusions: Economic hardship, ocular complications, and poor self-reported visual function are predictors of mental problems in patients with uveitis.


Asunto(s)
Oftalmopatías/diagnóstico , Estrés Financiero/diagnóstico , Trastornos Mentales/diagnóstico , Uveítis/diagnóstico , Baja Visión/diagnóstico , Adulto , Estudios Transversales , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Calidad de Vida , Curva ROC , Encuestas y Cuestionarios
11.
Gene ; 757: 144926, 2020 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-32621951

RESUMEN

Endometriosis is a frequent gynecologic disease in the world. CircRNAs can exert a crucial role in various diseases. Nevertheless, little is known about its roles in endometriosis. We investigated the involvement of circ_0061140 in endometriosis. Tissues from endometriosis women displayed an increased expression of circ_0061140. Then, we found loss of circ_0061140 significantly repressed ectopic endometrial cell proliferation, migration and invasion. Meanwhile,miR-140-3pcan demonstrate an important role in several cancers.Here, we reported miR-140-3p was reduced in ectopic endometrial cells and it acted as a target of circ_0061140. Moreover, miR-140-3p was able to reverse the effect of circ_0061140 on ectopic endometrial cells. Furthermore, Notch2 was predicted as a putative target of miR-140-3p. A positive correlation between circ_0061140 and Notch2 was indicated. miR-140-3p and Notch2 were operated as downstream effectors in the circ_0061140 mediated signaling in endometriosis. Decrease of circ_0061140 could depress endometriosis progression through modulating miR-140-3p and Notch2.


Asunto(s)
Movimiento Celular , Proliferación Celular , Endometriosis/genética , ARN Circular/genética , Células Cultivadas , Regulación hacia Abajo , Endometriosis/metabolismo , Endometriosis/patología , Endometrio/metabolismo , Endometrio/patología , Femenino , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular/metabolismo , Receptor Notch2/genética , Receptor Notch2/metabolismo
12.
Proc Natl Acad Sci U S A ; 117(26): 15055-15065, 2020 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-32554489

RESUMEN

Phosphocholine phosphatase-1 (PHOSPHO1) is a phosphocholine phosphatase that catalyzes the hydrolysis of phosphocholine (PC) to choline. Here we demonstrate that the PHOSPHO1 transcript is highly enriched in mature brown adipose tissue (BAT) and is further induced by cold and isoproterenol treatments of BAT and primary brown adipocytes. In defining the functional relevance of PHOPSPHO1 in BAT thermogenesis and energy metabolism, we show that PHOSPHO1 knockout mice are cold-tolerant, with higher expression of thermogenic genes in BAT, and are protected from high-fat diet-induced obesity and development of insulin resistance. Treatment of mice with the PHOSPHO1 substrate phosphocholine is sufficient to induce cold tolerance, thermogenic gene expression, and allied metabolic benefits. Our results reveal a role of PHOSPHO1 as a negative regulator of BAT thermogenesis, and inhibition of PHOSPHO1 or enhancement of phosphocholine represent innovative approaches to manage the metabolic syndrome.


Asunto(s)
Tejido Adiposo Pardo/fisiología , Monoéster Fosfórico Hidrolasas/genética , Fosforilcolina/metabolismo , Termogénesis , Adipocitos Marrones/enzimología , Adipocitos Marrones/metabolismo , Tejido Adiposo Pardo/enzimología , Animales , Frío , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Monoéster Fosfórico Hidrolasas/deficiencia
13.
Bone Res ; 8: 8, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32128276

RESUMEN

The most severe sequelae after rehabilitation from SARS are femoral head necrosis and pulmonary fibrosis. We performed a 15-year follow-up on the lung and bone conditions of SARS patients. We evaluated the recovery from lung damage and femoral head necrosis in an observational cohort study of SARS patients using pulmonary CT scans, hip joint MRI examinations, pulmonary function tests and hip joint function questionnaires. Eighty medical staff contracted SARS in 2003. Two patients died of SARS, and 78 were enrolled in this study from August 2003 to March 2018. Seventy-one patients completed the 15-year follow-up. The percentage of pulmonary lesions on CT scans diminished from 2003 (9.40 ± 7.83)% to 2004 (3.20 ± 4.78)% (P < 0.001) and remained stable thereafter until 2018 (4.60 ± 6.37)%. Between 2006 and 2018, the proportion of patients with interstitial changes who had improved pulmonary function was lower than that of patients without lesions, as demonstrated by the one-second ratio (FEV1/FVC%, t = 2.21, P = 0.04) and mid-flow of maximum expiration (FEF25%-75%, t = 2.76, P = 0.01). The volume of femoral head necrosis decreased significantly from 2003 (38.83 ± 21.01)% to 2005 (30.38 ± 20.23)% (P = 0.000 2), then declined slowly from 2005 to 2013 (28.99 ± 20.59)% and plateaued until 2018 (25.52 ± 15.51)%. Pulmonary interstitial damage and functional decline caused by SARS mostly recovered, with a greater extent of recovery within 2 years after rehabilitation. Femoral head necrosis induced by large doses of steroid pulse therapy in SARS patients was not progressive and was partially reversible.

14.
Int J Biol Macromol ; 143: 775-784, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31726133

RESUMEN

In this study, we investigated the structural characterization and antidiabetic effects of Lactobacillus H31 exopolysaccharide (EPS) H31-2 from pickled cabbage. The BLAST result indicated that Lactobacillus H31 was closely related to Lactobacillusplantarum S1S2L2. In the spectrum of Fourier-transform infrared spectroscopy (FT-IR), 3370 cm-1 was the characteristic band of polysaccharide. A structural analysis showed that the monosaccharides of EPS H31-2 included d-mannose (Man) and d-glucose (Glc). The molecular weight of EPS H31-2 was around 10.75 kDa. All these results suggested EPS H31-2 was a novel polysaccharide. The inhibition ratios of crude EPS H31 and the pure fraction H31-2 of pancreatic α-amylase were 89.1 ±â€¯2.59% and 69.2 ±â€¯8.95%, respectively. In addition, the supernatant glucose concentration of insulin-resistant HepG2 cells decreased by treatment with 10-8 M of EPS H31-2, which meant EPS H31-2 could promote the glucose uptake of insulin-resistant HepG2 cell. Furthermore, EPS H31-2 upregulated the expression of the GLUT-4, Akt-2, and AMPK, which play important roles in glycometabolism. These results suggested that Lactobacillus plantarum EPS H31-2 could effectively inhibit the activity of pancreas α-amylase and has potential applications in the prevention and alleviation of diabetes mellitus.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Brassica/microbiología , Lactobacillus plantarum/química , Páncreas/enzimología , Polisacáridos Bacterianos/farmacología , Transducción de Señal , alfa-Amilasas/antagonistas & inhibidores , Proteínas Quinasas Activadas por AMP/metabolismo , Glucemia/análisis , Células Hep G2 , Humanos , Hipoglucemiantes/farmacología , Metilación , Monosacáridos/análisis , Fosfatidilinositol 3-Quinasas/metabolismo , Filogenia , Proteínas Proto-Oncogénicas c-akt/metabolismo , Espectroscopía de Protones por Resonancia Magnética , Transducción de Señal/efectos de los fármacos , Espectroscopía Infrarroja por Transformada de Fourier , alfa-Amilasas/metabolismo
15.
Appl Microbiol Biotechnol ; 103(18): 7663-7674, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31297555

RESUMEN

The inhibitory effect of Bacillomycin D, a cyclic lipopeptide, on Rhizopus stolonifer colonization of cherry tomato was studied, and its possible mechanism of action was explored. Bacillomycin D showed a direct inhibitory effect on R. stolonifer spore germination and mycelial growth in vitro. It conferred both a direct inhibitory effect on R. stolonifer growth in cherry tomato in vivo and induced host resistance in cherry tomato. Moreover, Bacillomycin D treatment significantly increased the activities of plant defense-related enzymes, including chitinase (CHI), ß-1,3-glucanase (GLU), phenylalanine ammonia-lyase (PAL), and peroxidase (POD). Real-time PCR (RT-PCR) showed that defense-related genes involved in the salicylic acid defense signaling pathway and genes encoding pathogenesis-related proteins were up-regulated in Bacillomycin D treatment. Furthermore, Bacillomycin D-C16 resulted in direct inhibition and a remarkable induced resistance to R. stolonifer which was higher than as induced by Bacillomycin D-C14. Together, the data indicated that Bacillomycin D can control the growth of R. stolonifer through both the direct inhibition of the fungus and the activation of defense-related genes and enzymes in cherry tomato.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/farmacología , Frutas/microbiología , Rhizopus/efectos de los fármacos , Rhizopus/crecimiento & desarrollo , Solanum lycopersicum/microbiología , Quitinasas/metabolismo , Frutas/enzimología , Glucano 1,3-beta-Glucosidasa/metabolismo , Solanum lycopersicum/enzimología , Peroxidasa/metabolismo , Fenilanina Amoníaco-Liasa/metabolismo , Enfermedades de las Plantas/microbiología , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/crecimiento & desarrollo
16.
mBio ; 10(1)2019 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-30723127

RESUMEN

APOBEC3B is a single-stranded DNA cytosine deaminase with beneficial innate antiviral functions. However, misregulated APOBEC3B can also be detrimental by inflicting APOBEC signature C-to-T and C-to-G mutations in genomic DNA of multiple cancer types. Polyomavirus and papillomavirus oncoproteins induce APOBEC3B overexpression, perhaps to their own benefit, but little is known about the cellular mechanisms hijacked by these viruses to do so. Here we investigate the molecular mechanism of APOBEC3B upregulation by the polyomavirus large T antigen. First, we demonstrate that the upregulated APOBEC3B enzyme is strongly nuclear and partially localized to virus replication centers. Second, truncated T antigen (truncT) is sufficient for APOBEC3B upregulation, and the RB-interacting motif (LXCXE), but not the p53-binding domain, is required. Third, genetic knockdown of RB1 alone or in combination with RBL1 and/or RBL2 is insufficient to suppress truncT-mediated induction of APOBEC3B Fourth, CDK4/6 inhibition by palbociclib is also insufficient to suppress truncT-mediated induction of APOBEC3B Last, global gene expression analyses in a wide range of human cancers show significant associations between expression of APOBEC3B and other genes known to be regulated by the RB/E2F axis. These experiments combine to implicate the RB/E2F axis in promoting APOBEC3B transcription, yet they also suggest that the polyomavirus RB-binding motif has at least one additional function in addition to RB inactivation for triggering APOBEC3B upregulation in virus-infected cells.IMPORTANCE The APOBEC3B DNA cytosine deaminase is overexpressed in many different cancers and correlates with elevated frequencies of C-to-T and C-to-G mutations in 5'-TC motifs, oncogene activation, acquired drug resistance, and poor clinical outcomes. The mechanisms responsible for APOBEC3B overexpression are not fully understood. Here, we show that the polyomavirus truncated T antigen (truncT) triggers APOBEC3B overexpression through its RB-interacting motif, LXCXE, which in turn likely modulates the binding of E2F family transcription factors to promote APOBEC3B expression. This work strengthens the mechanistic linkage between active cell cycling, APOBEC3B overexpression, and cancer mutagenesis. Although this mutational mechanism damages cellular genomes, viruses may leverage it to promote evolution, immune escape, and pathogenesis. The cellular portion of the mechanism may also be relevant to nonviral cancers, where genetic mechanisms often activate the RB/E2F axis and APOBEC3B mutagenesis contributes to tumor evolution.


Asunto(s)
Antígenos Virales de Tumores/metabolismo , Citidina Desaminasa/biosíntesis , Interacciones Huésped-Patógeno , Antígenos de Histocompatibilidad Menor/biosíntesis , Poliomavirus/crecimiento & desarrollo , Proteína p53 Supresora de Tumor/metabolismo , Regulación hacia Arriba , Antígenos Virales de Tumores/genética , Sitios de Unión , Células Cultivadas , Factores de Transcripción E2F/metabolismo , Perfilación de la Expresión Génica , Humanos , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Neoplasias/patología , Proteínas de Unión a Retinoblastoma/metabolismo
17.
Endocrinology ; 159(9): 3365-3377, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30060148

RESUMEN

Steroid sulfatase (STS), a desulfating enzyme that converts steroid sulfates to hormonally active steroids, plays an important role in the homeostasis of sex hormones. STS is expressed in the adipose tissue of both male and female mice, but the role of STS in the development and function of adipose tissue remains largely unknown. In this report, we show that the adipose expression of Sts was induced in the high-fat diet (HFD) and ob/ob models of obesity and type 2 diabetes. Transgenic overexpression of the human STS in the adipose tissue of male mice exacerbated the HFD-induced metabolic phenotypes, including increased body weight gain and fat mass, and worsened insulin sensitivity, glucose tolerance, and energy expenditure, which were accounted for by adipocyte hypertrophy, increased adipose inflammation, and dysregulation of adipogenesis. The metabolic harm of the STS transgene appeared to have resulted from increased androgen activity in the adipose tissue, and castration abolished most of the phenotypes. Interestingly, the transgenic effects were sex specific, because the HFD-fed female STS transgenic mice exhibited improved metabolic functions, which were associated with attenuated adipose inflammation. The metabolic benefit of the STS transgene in female mice was accounted for by increased estrogenic activity in the adipose tissue, whereas such benefit was abolished upon ovariectomy. Our results revealed an essential role of the adipose STS in energy homeostasis in sex- and sex hormone-dependent manner. The adipose STS may represent a therapeutic target for the management of obesity and type 2 diabetes.


Asunto(s)
Tejido Adiposo/metabolismo , Andrógenos/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Metabolismo Energético/genética , Estrógenos/metabolismo , Obesidad/metabolismo , Caracteres Sexuales , Esteril-Sulfatasa/genética , Adipogénesis , Tejido Adiposo/inmunología , Tejido Adiposo/patología , Animales , Peso Corporal , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Femenino , Prueba de Tolerancia a la Glucosa , Hormonas Esteroides Gonadales/metabolismo , Humanos , Inflamación , Resistencia a la Insulina , Lipólisis , Masculino , Ratones , Ratones Obesos , Ratones Transgénicos , Obesidad/inmunología , Orquiectomía , Ovariectomía , Esteril-Sulfatasa/metabolismo , Transcriptoma
18.
Nat Commun ; 8(1): 2115, 2017 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-29235464

RESUMEN

Brown adipose tissue (BAT) metabolism influences glucose homeostasis and metabolic health in mice and humans. Sympathetic stimulation of ß-adrenergic receptors in response to cold induces proliferation, differentiation, and UCP1 expression in pre-adipocytes and mature brown adipocytes. Here we show that spleen tyrosine kinase (SYK) is upregulated during brown adipocyte differentiation and activated by ß-adrenergic stimulation. Deletion or inhibition of SYK, a kinase known for its essential roles in the immune system, blocks brown and white pre-adipocyte proliferation and differentiation in vitro, and results in diminished expression of Ucp1 and other genes regulating brown adipocyte function in response to ß-adrenergic stimulation. Adipocyte-specific SYK deletion in mice reduces BAT mass and BAT that developed consisted of SYK-expressing brown adipocytes that had escaped homozygous Syk deletion. SYK inhibition in vivo represses ß-agonist-induced thermogenesis and oxygen consumption. These results establish SYK as an essential mediator of brown fat formation and function.


Asunto(s)
Adipocitos Marrones/enzimología , Tejido Adiposo Pardo/metabolismo , Diferenciación Celular , Quinasa Syk/metabolismo , Adipocitos Marrones/citología , Animales , Proliferación Celular , Células Cultivadas , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Quinasa Syk/genética , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
19.
Adv Exp Med Biol ; 1043: 455-469, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29224107

RESUMEN

Sulfonation and desulfation are two opposing processes that represent an important layer of regulation of estrogenic activity via ligand supplies. Enzymatic activities of families of enzymes, known as sulfotransferases and sulfatases, lead to structural and functional changes of the steroids, thyroids, xenobiotics, and neurotransmitters. Estrogen sulfotransferase (EST) and steroid sulfatase (STS) represent negative and positive regulation of the estrogen activity, respectively. This is because EST-mediated sulfation deactivates estrogens, whereas STS-mediated desulfation converts the inactive estrogen sulfates to active estrogens. In addition to the known functions of estrogens, EST and STS in reproductive processes, regulation of estrogens and other signal molecules especially at the local tissue levels has gained increased attention in the context of metabolic disease in recent years. EST expression is detectable in the subcutaneous adipose tissue in both obese women and men, and the expression of EST is markedly induced in the livers of rodent models of obesity and type 2 diabetes. STS was found to be upregulated in patients with chronic inflammatory liver diseases. Interestingly, the tissue distribution and the transcriptional regulation of EST and STS exhibit obvious sex and species specificity. EST ablation produces completely opposite metabolic phenotype in female and male obese mice. Adipogenesis is also differentially regulated by EST in murine and human adipocytes. This chapter focuses on the recent progress in our understanding of the expression and regulation EST and STS in the context of metabolic homeostasis.


Asunto(s)
Metabolismo Energético , Estrógenos/metabolismo , Esteril-Sulfatasa/metabolismo , Sulfotransferasas/metabolismo , Animales , Femenino , Homeostasis , Humanos , Masculino , Caracteres Sexuales , Factores Sexuales , Transducción de Señal , Especificidad de la Especie
20.
Liver Res ; 1(1): 63-69, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29130021

RESUMEN

BACKGROUND AND AIM: Sulfotransferase (SULT)-mediated sulfation and steroid sulfatase (STS)-mediated desulfation represent two critical mechanisms that regulate the chemical and functional homeostasis of endogenous and exogenous molecules. STS catalyzes the hydrolysis of steroid sulfates to form hydroxysteroids. Oxygenated cholesterol derivative oxysterols are known to be endogenous ligands of the liver X receptor (LXR), a nuclear receptor with anti-cholestasis activity, whereas the sulfated oxysterols antagonize LXR signaling. The conversion of sulfated oxysterols to their non-sulfated counterparts is catalyzed by STS. The aim of this study is to determine whether STS can alleviate cholestasis by increasing the activity of LXR. METHODS: Liver-specific STS transgenic mice were created and subject to the lithocholic acid (LCA)-induced model of cholestasis. RESULTS: Transgenic overexpression of STS in the liver promoted bile acid elimination and alleviated LCA-induced cholestasis. The protective effect of the STS transgene was associated with the activation of LXR and induction of LXR target genes, likely because of the increased conversion of the antagonistic oxysterol sulfates to the agonistic oxysterols. CONCLUSIONS: STS has a novel function in controlling the homeostasis of bile acids by regulating endogenous LXR ligands.

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