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1.
Cell Prolif ; 53(1): e12705, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31657086

RESUMO

OBJECTIVES: Increasing evidences demonstrate a close correlation between epithelial-to-mesenchymal transition (EMT) induction and cancer lipid metabolism. However, the molecular mechanisms have not been clarified. MATERIALS AND METHODS: In our study, the relative expression level of PRRX1 was detected, its relationship with free fatty acid (FFA) and PPARG2 was analysed in 85 SACC tissues and 15 salivary glands from the benign salivary tumours. We also compared the FFAs composition and levels in these SACC cells. PPARG2 was detected in PRRX1-induced FFAs treatment as well as Src and MMP-9 were detected in FFAs treatment-induced invasion and migration of SACC cells, and ChIP test was performed to identify the target interactions. RESULTS: Our data showed that overexpression of PRRX1 induced EMT and facilitated the invasion and migration of SACC cells, and PRRX1 expression was closely associated with high FFAs level and poor prognosis of SACC patients. Furthermore, PRRX1 silence led to the increase of PPARG2 and the reduction of FFAs level and the migration and invasion of SACC cells. And inhibition of PPARG2 rescued FFAs level and migration and invasion capabilities of SACC cells. Free fatty acids treatment induced an increase of Stat5-DNA binding activity via Src- and MMP-9-dependent pathway. CONCLUSIONS: Collectively, our findings showed that the PRRX1/PPARG2/FFAs signalling in SACC was important for accelerating tumour metastasis through the induction of EMT and the metabolic reprogramming of FFAs.


Assuntos
Carcinoma Adenoide Cístico/metabolismo , Reprogramação Celular , Transição Epitelial-Mesenquimal , Ácidos Graxos/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias das Glândulas Salivares/metabolismo , Animais , Carcinoma Adenoide Cístico/genética , Carcinoma Adenoide Cístico/patologia , Linhagem Celular Tumoral , Ácidos Graxos/genética , Proteínas de Homeodomínio/genética , Humanos , Camundongos , Invasividade Neoplásica , Metástase Neoplásica , Proteínas de Neoplasias/genética , Neoplasias das Glândulas Salivares/genética , Neoplasias das Glândulas Salivares/patologia
2.
Chem Biol Interact ; 315: 108869, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31682803

RESUMO

Spermatogenic dysfunction is one of the major secondary complications of male diabetes. Salidroside (SAL) is the important active ingredients isolated from Herba Cistanche, which exhibits numerous pharmacological activities such as antioxidant, anti-diabetic, and anti-inflammatory effects. The present study was designed to determine whether SAL contributes to the recovery from spermatogenic dysfunction in streptozotocin (STZ) induced type-1 diabetic mice. SAL (25, 50, or 100 mg/kg) and Clomiphene citrate (CC, 5 mg/kg) were orally administered to male type-1 diabetic mice for 10 weeks. Testis tissues were collected for histopathological and biochemical analysis. Moreover, reproductive organ weight, sperm parameters, and testicular cell DNA damage were estimated. The results revealed that SAL significantly improved the weight of the reproductive organs, sperm parameters and testicular morphology to different degrees in type-1 diabetic mice. Furthermore, reactive oxygen species (ROS) and malondialdehyde (MDA) levels were significantly reduced, and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), markedly increased in the testicular tissue after SAL treatment. In addition, our data also showed a marked downregulation the fluorescence expressions of p38 MAPK phosphorylation and upregulation the protein expressions of ZO-1, Occludin, Claudin-11 and N-cadherin after SAL administration (100 mg/kg) compared with the type-1 diabetic group. In conclusion, these results demonstrated that SAL exerts protective effects on type-1 diabetes-induced male spermatogenic dysfunction, which is likely mediated by inhibiting oxidative stress-mediated blood testis barrier damage.


Assuntos
Barreira Hematotesticular/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Glucosídeos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia , Substâncias Protetoras/farmacologia , Espermatogênese/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Barreira Hematotesticular/metabolismo , Catalase/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/metabolismo , Glutationa/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Contagem de Espermatozoides/métodos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Estreptozocina/farmacologia , Superóxido Dismutase/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo
3.
Blood ; 134(Supplement_1): 7, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31724004

RESUMO

DISCLOSURES: No relevant conflicts of interest to declare.

4.
Biomed Pharmacother ; 120: 109474, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31585299

RESUMO

BACKGROUND: Blood-testis barrier (BTB) impairments is one of the major secondary complications of diabetes. Betaine (BET) is the important active ingredients isolated from Lycium barbarum, which exhibits numerous pharmacological activities such as antioxidant, anti-diabetic, and anti-inflammatory effects. This study aimed to establish whether BET contributes to the recovery from BTB dysfunction in streptozotocin (STZ) induced diabetic mice. METHODS: BET (200, 400, 800 mg/kg) was orally administered to diabetic mice for 8 weeks. Testis tissues were collected for histopathological and biochemical analysis, the reproductive organ weight was estimated. Antioxidant enzyme activity and BTB associated protein expressions were determined with their corresponding assay kits and western blot analysis. The results revealed that BET significantly improved the weight of the reproductive organs and testicular morphology in diabetic mice. Furthermore, reactive oxygen species (ROS) and malondialdehyde (MDA) levels were significantly reduced, and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), markedly increased in the testicular tissue after SAL treatment. In addition, our data also showed a marked down-regulated the expressions of p38 MAPK phosphorylation and up-regulation the protein expressions of ZO-1, Occludin, Claudin-11, N-cadherin, and Connexin-43 after BET administration compared with the diabetic group. In conclusion, these results demonstrated that BET exerts protective effects on diabetes-induced BTB dysfunction, which may be through regulating oxidative stress-mediated p38 MAPK pathways.

5.
Cell Rep ; 29(5): 1287-1298.e6, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31665640

RESUMO

Glutamine is thought to play an important role in cancer cells by being deaminated via glutaminolysis to α-ketoglutarate (aKG) to fuel the tricarboxylic acid (TCA) cycle. Supporting this notion, aKG supplementation can restore growth/survival of glutamine-deprived cells. However, pancreatic cancers are often poorly vascularized and limited in glutamine supply, in alignment with recent concerns on the significance of glutaminolysis in pancreatic cancer. Here, we show that aKG-mediated rescue of glutamine-deprived pancreatic ductal carcinoma (PDAC) cells requires glutamate ammonia ligase (GLUL), the enzyme responsible for de novo glutamine synthesis. GLUL-deficient PDAC cells are capable of the TCA cycle but defective in aKG-coupled glutamine biosynthesis and subsequent nitrogen anabolic processes. Importantly, GLUL expression is elevated in pancreatic cancer patient samples and in mouse PDAC models. GLUL ablation suppresses the development of KrasG12D-driven murine PDAC. Therefore, GLUL-mediated glutamine biosynthesis couples the TCA cycle with nitrogen anabolism and plays a critical role in PDAC.

6.
Oncotarget ; 10(42): 4307-4320, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31303964

RESUMO

Cell migration-inducing protein (CEMIP) and binding immunoglobulin protein (BiP) are upregulated in human cancers, where they drive cancer progression and metastasis. It has been shown that CEMIP resides in the endoplasmic reticulum (ER) where it interacts with BiP to induce cell migration, but the relationship between the two proteins was previously unknown. Here we show that CEMIP mediates activation of the BiP promoter and upregulates BiP transcript and protein levels in breast cancer cell lines. Moreover, CEMIP overexpression confers protective adaptations to cancer cells under hypoxic conditions, by decreasing apoptosis, activating autophagy, and increasing glucose uptake, to facilitate tumor growth. We demonstrate that BiP signals downstream of CEMIP, modulating cellular resistance to hypoxia. Reducing BiP in CEMIP-expressing cells sensitized cells to hypoxia treatment, decreased glucose uptake, and resulted in tumor regression in vivo. Our study provides insights into the link between CEMIP and BiP expression and the pro-survival role they play in hypoxia. Better understanding of the mechanisms behind cancer cell adaptations to harsh tumor environments could lead to development of improved cancer treatments.

7.
J Gen Physiol ; 151(8): 1051-1058, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31217223

RESUMO

Heart rate in physiological conditions is set by the sinoatrial node (SN), the primary cardiac pacing tissue. Phosphoinositide 3-kinase (PI3K) signaling is a major regulatory pathway in all normal cells, and its dysregulation is prominent in diabetes, cancer, and heart failure. Here, we show that inhibition of PI3K slows the pacing rate of the SN in situ and in vitro and reduces the early slope of diastolic depolarization. Furthermore, inhibition of PI3K causes a negative shift in the voltage dependence of activation of the pacemaker current, I F, while addition of its second messenger, phosphatidylinositol 3,4,5-trisphosphate, induces a positive shift. These shifts in the activation of I F are independent of, and larger than, those induced by the autonomic nervous system. These results suggest that PI3K is an important regulator of heart rate, and perturbations in this signaling pathway may contribute to the development of arrhythmias.

8.
J Clin Invest ; 129(8): 3264-3276, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31112530

RESUMO

The presence of tumor-infiltrating T cells is associated with favorable patient outcomes, yet most pancreatic cancers are immunologically silent and resistant to currently available immunotherapies. Here we show using a syngeneic orthotopic implantation model of pancreatic cancer that Pik3ca regulates tumor immunogenicity. Genetic silencing of Pik3ca in KrasG12D/Trp53R172H-driven pancreatic tumors resulted in infiltration of T cells, complete tumor regression, and 100% survival of immunocompetent host mice. By contrast, Pik3ca-null tumors implanted in T cell-deficient mice progressed and killed all of the animals. Adoptive transfer of tumor antigen-experienced T cells eliminated Pik3ca-null tumors in immunodeficient mice. Loss of PIK3CA or inhibition of its effector, AKT, increased the expression of MHC Class I and CD80 on tumor cells. These changes contributed to the increased susceptibility of Pik3ca-null tumors to T cell surveillance. Our results indicate that tumor cell PIK3CA-AKT signaling limits T cell recognition and clearance of pancreatic cancer cells. Strategies that target this pathway may yield an effective immunotherapy for this cancer.

9.
Biomed Pharmacother ; 110: 561-570, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30537673

RESUMO

Spermatogenic dysfunction is a common complication in men with diabetes and is the most important manifestation of diabetes-related male reproduction damage. Astragalin (AG) is one of the main flavonoids from Cuscuta chinensis, which has rich pharmacological activities. This study aimed to establish whether AG may contribute to the recovery from spermatogenic dysfunction. AG (3.3, 10 and 30 mg/kg) and Clomiphene (5 mg/kg) were orally administered to streptozotocin-induced diabetic male mice for 8 weeks. After the experiments performed, reproductive organs, sperm parameters and histomorphological changes were analysed. Antioxidant and anti-inflammatory capacity were estimated in testicular tissues. The results revealed that AG significantly improved the reproductive organs, sperm parameters and testicular morphology to different degrees in diabetic mice. Nitric oxide (NO) and malondialdehyde (MDA) levels were significantly reduced, and the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), markedly increased in the testicular tissue after AG was administered. Interestingly, AG also downregulated the protein expressions of tumour necrosis factor-α (TNF-α) and inducible nitric oxide synthase (iNOS) in testes. In conclusion, AG is a potential beneficial agent to protect diabetic-induced spermatogenic dysfunction in male mice by increasing antioxidant enzymes activities and inhibiting inflammation.


Assuntos
Antioxidantes/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Mediadores da Inflamação/metabolismo , Quempferóis/uso terapêutico , Espermatogênese/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Mediadores da Inflamação/antagonistas & inibidores , Quempferóis/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Distribuição Aleatória , Espermatogênese/fisiologia , Resultado do Tratamento
10.
Chem Biol Interact ; 297: 119-129, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30365938

RESUMO

Diabetes-associated sexual dysfunction and fertility impairments are major secondary complications in diabetic patients and animal models. Natural herbs are important sources of therapeutic agents for diabetic complications. This study investigated the effect of vitexin on male sexual dysfunction and fertility impairments in streptozotocin (STZ)-induced diabetic mice. Diabetes was induced by intraperitoneal injection of 45 mg/kg STZ for 5 consecutive days in mice. Vitexin (10, 20 or 40 mg/kg) and Sildenafil citrate (SC, 5 mg/kg) were administered daily for 62 days after the induction of diabetes. The parameters of sexual behavior and fertility were analyzed. The reproductive organ weight, sperm motility, and viability of the treated mice were examined. Testicular histopathological alterations were detected by hematoxylin and eosin (H&E) staining. Enzyme-linked immunosorbent assay (ELISA) was used to evaluate serum hormonal levels. Results showed that 40 mg/kg vitexin significantly improved the sexual behavior and fertility levels compared with the diabetic group. Moreover, vitexin (20 or 40 mg/kg) significantly increased reproductive organ weight and improved testicular pathological structure damage. Meanwhile, sperm analysis demonstrated that vitexin significantly restored sperm quality in a dose-dependent manner. Furthermore, ELISA data showed that vitexin significantly increased the serum testosterone (T), follicular-stimulating hormone (FSH), and luteinizing hormone (LH) levels but decreased the gonadotropin-releasing hormone (GnRH) level to different degrees. These findings suggest that vitexin ameliorates sexual dysfunction and fertility impairments in male diabetic mice possibly by modulating the hypothalamus-pituitary-gonadal axis.


Assuntos
Apigenina/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Fertilidade/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Animais , Apigenina/administração & dosagem , Apigenina/química , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/induzido quimicamente , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Injeções Intraperitoneais , Masculino , Camundongos , Estrutura Molecular , Disfunções Sexuais Fisiológicas/induzido quimicamente , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Estreptozocina/administração & dosagem , Relação Estrutura-Atividade
11.
Cell Tissue Res ; 374(3): 653-666, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30073544

RESUMO

Testicular dysfunction is one of the serious secondary complications in diabetes. Lycium barbarum polysaccharide (LBP) has long been considered to possess a wide range of beneficial properties including antiaging, anticancer and reproductive-enhancing. Abnormal autophagy was reported to play a significant role in accelerating diabetic reproductive injury. However, the autophagy regulation mechanism of LBP on diabetic testicular dysfunction is incompletely understood. We investigate the protective effects of LBP on diabetic testicular dysfunction and its underlying mechanism with different approaches. Protective effects of LBP (40 mg/kg) on testicular functions were assessed through the use of sperm parameters, testosterone levels and hematoxylin and eosin staining. Antioxidant capacity and serum malondialdehyde levels were determined using assay kits. Immune intensity of Beclin-1 and LC3I in testes was detected by immunofluorescence staining. Western blot analysis was used to detect expressions of p-PI3K, Akt, p-Akt, Beclin-1, LC3I and LC3II proteins. Q-PCR was used to evaluate Beclin-1 and LC3I mRNA expressions in testis. Administration of LBP (40 mg/kg) considerably recovered testicular function, obviously improved testicular histopathologic structure and significantly increased antioxidant enzyme activities. Immunofluorescence staining showed that immune intensity of Beclin-1 and LC3I significantly decreased in the LBP 40 mg/kg group. The results of Q-PCR and western blot analysis showed that LBP 40 mg/kg significantly downregulated Beclin-1 and LC3I protein expressions upregulated p-PI3K and p-Akt protein expressions and decreased Beclin-1 and LC3I mRNA expressions compared with diabetic mice. In conclusion, inhibition of PI3K/Akt pathway-mediated testicular excessive autophagy may be a target for protective effects of LBP on diabetic testicular dysfunction.


Assuntos
Autofagia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/fisiopatologia , Medicamentos de Ervas Chinesas/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Testículo/patologia , Testículo/fisiopatologia , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Autofagossomos/ultraestrutura , Autofagia/efeitos dos fármacos , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Proteína Beclina-1/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/genética , Medicamentos de Ervas Chinesas/farmacologia , Masculino , Camundongos Endogâmicos ICR , Proteínas Associadas aos Microtúbulos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testosterona/sangue
12.
Biomed Pharmacother ; 103: 29-37, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29635125

RESUMO

Chemotherapy could be used as an effective therapeutic treatment for ovarian cancer and subsequent peritoneal metastasis. However, the occurrence of drug resistance reduced the treatment effect originated from cancer chemotherapy. Accumulating evidences indicated the significant role of autophagy in tumor cell resistance to chemotherapy. Thus, inhibition of autophagy using natural compounds could be a promising candidate to overcome multidrug resistance in human ovarian cancer cells. Nobiletin (NOB), a polymethoxyflavonoid found in citrus fruits such as Citrus depressa and Citrus reticulate, exhibits a number of bioactivities. In the present study, NOB selectively suppressed the growth and proliferation of human SKOV3/TAX cells, inducing G0/G1 phase arrest and reducing G2/M phase, along with the increase of p53 and p21. In addition, NOB induced significant apoptosis in SKOV3/TAX cells through the intrinsic apoptosis pathway, as evidenced by the up-regulation of cleaved Caspase-9/-3 and PARP. Further, NOB impaired the autophagic degradation in SKOV3/TAX cells, resulting in autophagic flux inhibition. Moreover, the impaired autophagic flux enhanced NOB-induced apoptosis in SKOV3/TAX cells. Importantly, AKT signaling was activated by NOB, which was involved in autophagic degradation and apoptotic cell death. In conclusion, the findings here supplied the illustration that NOB could overcome multidrug resistance in human ovarian cancer cells through AKT-regulated suppression of autophagic degradation.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Flavonas/farmacologia , Neoplasias Ovarianas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Feminino , Flavonas/química , Humanos , Modelos Biológicos , Neoplasias Ovarianas/enzimologia , Proteína Supressora de Tumor p53/metabolismo
13.
Biomed Pharmacother ; 101: 510-527, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29505922

RESUMO

Diabetes mellitus (DM) is a major endocrine metabolic disease and is marked by a lack of insulin. The complication of DM is one of the most difficult problems in medicine. The initial translational studies revealed that growth factors have a major role in integrating tissue physiology and in embryology as well as in growth, maturation and tissue repair. In some tissues affected by diabetes, growth factors are induced by a relative deficit or excess. Fibroblast growth factor 21 (FGF21) is a promising regulator of glucose and lipid metabolism with multiple beneficial effects including hypoglycemic and lipid-lowering. Vascular endothelial growth factor (VEGF) is a potent angiogenic and vascular permeability factor and is implicated in both of these complications in diabetes. Increase or decrease in the production of transforming growth factor-ß1 (TGF-ß1) has been associated with diabetic nephropathy and retinopathy. The insulin-like growth factor-I (IGF-I) is a naturally-occurring single chain polypeptide which has been widely used in the treatment of diabetic glomerular and renal tubular injuries. This review summarizes the recent evidences for an involvement of growth factors in diabetic complications, focusing on their emergence in sequence of events leading to vascular complications or their potential therapeutic role in these diseases. Growth factor therapy in diabetic foot ulcers is already a clinical reality. As methods to finely regulate growth factors in a tissue and time-specific manner are further developed and tested, regulation of the growth factor to normal level in vivo may well become a therapy to prevent and treat diabetic complications.


Assuntos
Complicações do Diabetes/metabolismo , Diabetes Mellitus/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Animais , Humanos
14.
Circ Arrhythm Electrophysiol ; 10(5): e004508, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28500172

RESUMO

BACKGROUND: Although multiple approaches have been used to create biological pacemakers in animal models, induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) have not been investigated for this purpose. We now report pacemaker function of iPSC-CMs in a canine model. METHODS AND RESULTS: Embryoid bodies were derived from human keratinocytes, their action potential characteristics determined, and their gene expression profiles and markers of differentiation identified. Atrioventricular blocked dogs were immunosuppressed, instrumented with VVI pacemakers, and injected subepicardially into the anterobasal left ventricle with 40 to 75 rhythmically contracting embryoid bodies (totaling 1.3-2×106 cells). ECG and 24-hour Holter monitoring were performed biweekly. After 4 to 13 weeks, epinephrine (1 µg kg-1 min-1) was infused, and the heart removed for histological or electrophysiological study. iPSC-CMs largely lost the markers of pluripotency, became positive for cardiac-specific markers. and manifested If-dependent automaticity. Epicardial pacing of the injection site identified matching beats arising from that site by week 1 after implantation. By week 4, 20% of beats were electronically paced, 60% to 80% of beats were matching, and mean and maximal biological pacemaker rates were 45 and 75 beats per minute. Maximum night and day rates of matching beats were 53±6.9 and 69±10.4 beats per minute, respectively, at 4 weeks. Epinephrine increased rate of matching beats from 35±4.3 to 65±4.0 beats per minute. Incubation of embryoid bodies with the vital dye, Dil, revealed the persistence of injected cells at the site of administration. CONCLUSIONS: iPSC-CMs can integrate into host myocardium and create a biological pacemaker. Although this is a promising development, rate and rhythm of the iPSC-CMs pacemakers remain to be optimized.


Assuntos
Bloqueio Atrioventricular/cirurgia , Relógios Biológicos , Diferenciação Celular , Frequência Cardíaca , Células-Tronco Pluripotentes Induzidas/transplante , Miócitos Cardíacos/transplante , Transplante de Células-Tronco , Potenciais de Ação , Animais , Bloqueio Atrioventricular/metabolismo , Bloqueio Atrioventricular/fisiopatologia , Estimulação Cardíaca Artificial , Linhagem Celular , Modelos Animais de Doenças , Cães , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Perfilação da Expressão Gênica/métodos , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Miócitos Cardíacos/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Recuperação de Função Fisiológica , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Fatores de Tempo , Transcriptoma , Transfecção
15.
PLoS One ; 12(5): e0176713, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28464037

RESUMO

Our previous work on angiotensin II-mediated electrical-remodeling in canine left ventricle, in connection with a long history of other studies, suggested the hypothesis: increases in mechanical load induce autocrine secretion of angiotensin II (A2), which coherently regulates a coterie of membrane ion transporters in a manner that increases contractility. However, the relation between load and A2 secretion was correlative. We subsequently showed a similar or identical system was present in murine heart. To investigate whether the relation between mechanical load and A2-mediated electrical remodeling was causal, we employed transverse aortic constriction in mice to subject the left ventricle to pressure overload for short-term (1 to 2 days) or long-term (1 to 2 weeks) periods. Heart-to-body weight ratios and cell capacitance measurements were used to determine hypertrophy. Whole-cell patch clamp recordings of the predominant repolarization currents Ito,fast and IK,slow were used to assess electrical remodeling. Hearts or myocytes subjected to long-term load displayed significant hypertrophy, which was not evident in short-term load. However, short-term load induced significant reductions in Ito,fast and IK,slow. Incubation of these myocytes with the angiotensin II type 1 receptor inhibitor saralasin for 2 hours restored Ito,fast and IK,slow to control levels. The number of Ito.fast or IK,slow channels did not change with A2 or long-term load, however the hypertrophic increase in membrane area reduced the current densities for both channels. For Ito,fast but not IK,slow there was an additional reduction that was reversed by inhibition of angiotensin receptors. These results suggest increased load activates an endogenous renin angiotensin system that initially reduces Ito,fast and IK,slow prior to the onset of hypertrophic growth. However, there are functional interactions between electrical and anatomical remodeling. First, hypertrophy tends to reduce all current densities. Second, the hypertrophic program can modify signaling between the angiotensin receptor and target current.


Assuntos
Angiotensina II/metabolismo , Cardiopatias/fisiopatologia , Miócitos Cardíacos/fisiologia , Sistema Renina-Angiotensina/fisiologia , Estresse Fisiológico/fisiologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Hipertrofia/fisiopatologia , Potenciais da Membrana/fisiologia , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Técnicas de Patch-Clamp , Pressão , Receptor Tipo 1 de Angiotensina/metabolismo , Sistema Renina-Angiotensina/efeitos dos fármacos , Saralasina/farmacologia , Estresse Fisiológico/efeitos dos fármacos
16.
J Cardiovasc Pharmacol ; 69(4): 198-211, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28376509

RESUMO

Receptors that activate the heterotrimeric G protein Gαq are thought to play a role in the development of heart failure. Dysregulation of autophagy occurs in some pathological cardiac conditions including heart failure, but whether Gαq is involved in this process is unknown. We used a cardiomyocyte-specific transgenic mouse model of inducible Gαq activation (termed GαqQ209L) to address this question. After 7 days of Gαq activation, GαqQ209L hearts contained more autophagic vacuoles than wild type hearts. Increased levels of proteins involved in autophagy, especially p62 and LC3-II, were also seen. LysoTracker staining and western blotting showed that the number and size of lysosomes and lysosomal protein levels were increased in GαqQ209L hearts, indicating enhanced lysosomal degradation activity. Importantly, an autophagic flux assay measuring LC3-II turnover in isolated adult cardiomyocytes indicated that autophagic activity is enhanced in GαqQ209L hearts. GαqQ209L hearts exhibited elevated levels of the autophagy initiation complex, which contains the Class III phosphoinositide 3-kinase Vps34. As a consequence, Vps34 activity and phosphatidylinositol 3-phosphate levels were higher in GαqQ209L hearts than wild type hearts, thus accounting for the higher abundance of autophagic vacuoles. These results indicate that an increase in autophagy is an early response to Gαq activation in the heart.


Assuntos
Autofagia/fisiologia , Classe III de Fosfatidilinositol 3-Quinases/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Células Cultivadas , Ativação Enzimática/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
17.
PLoS One ; 12(2): e0171341, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28152077

RESUMO

Collective invasion of cells plays a fundamental role in tissue growth, wound healing, immune response and cancer metastasis. This paper aimed to investigate cytokeratin-14 (CK14) expression and analyze its association with collective invasion in the invasive front of salivary adenoid cystic carcinoma (SACC) to uncover the role of collective invasion in SACC. Here, in the clinical data of 121 patients with SACC, the positive expression of CK14 was observed in 35/121(28.93%) of the invasive front of SACC. CK14 expression in the invasive front, local regional recurrence and distant metastasis were independent and significant prognostic factors in SACC patients. Then, we found that in an ex vivo 3D culture assay, CK14 siRNA receded the collective invasion, and in 2D monolayer culture, CK14 overexpression induced a collective SACC cell migration. These data indicated that the presence of characterized CK14+ cells in the invasive front of SACC promoted collective cell invasion of SACC and may be a biomarker of SACC with a worse prognosis.


Assuntos
Carcinoma Adenoide Cístico/fisiopatologia , Queratina-14/fisiologia , Neoplasias das Glândulas Salivares/fisiopatologia , Carcinoma Adenoide Cístico/mortalidade , Carcinoma Adenoide Cístico/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/fisiopatologia , Neoplasias das Glândulas Salivares/mortalidade , Neoplasias das Glândulas Salivares/patologia , Técnicas de Cultura de Tecidos
18.
Oncotarget ; 8(7): 12472-12483, 2017 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-27992370

RESUMO

Noncoding RNAs (ncRNAs) have been demonstrated to closely associate with gene regulation and encompass the well-known microRNAs (miRNAs), as well as the most recently acknowledged long noncoding RNAs (lncRNAs). Current evidence indicates that lncRNAs can interact with miRNAs and these interactions play crucial roles in cancer metastasis, through regulating critical events especially the epithelial-mesenchymal transition (EMT). This review summarizes the types of lncRNA-miRNA crosstalk identified to-date and discusses their influence on the epithelial-mesenchymal plasticity and clinical metastatic implication.


Assuntos
Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias/genética , RNA Longo não Codificante/genética , Humanos , Modelos Genéticos , Metástase Neoplásica , Neoplasias/patologia , Estabilidade de RNA/genética , Transdução de Sinais/genética
19.
J Huazhong Univ Sci Technolog Med Sci ; 36(5): 752-757, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27752895

RESUMO

This study aimed to conduct measurement uncertainty assessment of a new method for determination of Sudan colorants (Sudan I, II, III and IV) in food by high performance liquid chromatography (HPLC). Samples were extracted with organic solvents (hexane, 20% acetone) and first purified by magnesium trisilicate (2MgO·3SiO2). The Sudan colorants (Sudan I-IV) were also initially separated on C8 by gradient elution using acetonitrile and 0.1% (v/v) formic acid aqueous solution as the mobile phases and detected with diode-array detector (DAD). The uncertainty of mathematical model of Sudan I, II, III and IV is based on EURACHEM guidelines. The sources and components of uncertainty were calculated. The experiment gave a good linear relationship over the concentration from 0.4 to 4.0 µg/mL and spiked recoveries were from 74.0% to 97.5%. The limits of determination (LOD) were 48, 61, 36, 58 µg/kg for the four analytes, respectively. The total uncertainty of Sudan colorants (Sudan I, II, III and IV) was 810±30.8, 790±28.4, 750±27.0, 730±50.0 µg/kg, respectively. The recovery uncertainty was the most significant factor contributing to the total uncertainty. The developed method is simple, rapid, and highly sensitive. It can be used for the determination of trace Sudan dyes in food samples. The sources of uncertainty have been identified and uncertainty components have been simplified and considered.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Corantes de Alimentos/isolamento & purificação , Silicatos de Magnésio/química , Compostos Azo/química , Compostos Azo/isolamento & purificação , Corantes de Alimentos/química , Humanos , Limite de Detecção , Naftóis/química , Naftóis/isolamento & purificação
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