Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
J Cell Physiol ; 235(12): 9958-9973, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32474911

RESUMO

Nephron loss stimulates residual functioning nephrons to undergo compensatory growth. Excessive nephron growth may be a maladaptive response that sets the stage for progressive nephron damage, leading to kidney failure. To date, however, the mechanism of nephron growth remains incompletely understood. Our previous study revealed that class III phosphatidylinositol-3-kinase (Pik3c3) is activated in the remaining kidney after unilateral nephrectomy (UNX)-induced nephron loss, but previous studies failed to generate a Pik3c3 gene knockout animal model. Global Pik3c3 deletion results in embryonic lethality. Given that renal proximal tubule cells make up the bulk of the kidney and undergo the most prominent hypertrophic growth after UNX, in this study we used Cre-loxP-based approaches to demonstrate for the first time that tamoxifen-inducible SLC34a1 promoter-driven CreERT2 recombinase-mediated downregulation of Pik3c3 expression in renal proximal tubule cells alone is sufficient to inhibit UNX- or amino acid-induced hypertrophic nephron growth. Furthermore, our mechanistic studies unveiled that the SLC34a1-CreERT2 recombinase-mediated Pik3c3 downregulation inhibited UNX- or amino acid-stimulated lysosomal localization and signaling activation of mechanistic target of rapamycin complex 1 (mTORC1) in the renal proximal tubules. Moreover, our additional cell culture experiments using RNAi confirmed that knocking down Pik3c3 expression inhibited amino acid-stimulated mTORC1 signaling and blunted cellular growth in primary cultures of renal proximal tubule cells. Together, both our in vivo and in vitro experimental results indicate that Pik3c3 is a major mechanistic mediator responsible for sensing amino acid availability and initiating hypertrophic growth of renal proximal tubule cells by activation of the mTORC1-S6K1-rpS6 signaling pathway.


Assuntos
Classe III de Fosfatidilinositol 3-Quinases/genética , Túbulos Renais Proximais/crescimento & desenvolvimento , Rim/efeitos dos fármacos , Néfrons/crescimento & desenvolvimento , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIa/genética , Animais , Classe III de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Proteínas da Matriz Extracelular/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Integrases/genética , Rim/crescimento & desenvolvimento , Rim/patologia , Rim/cirurgia , Túbulos Renais Proximais/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Camundongos , Nefrectomia , Néfrons/metabolismo , Fosforilação/genética , Proteína-Lisina 6-Oxidase/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia
2.
Am J Physiol Renal Physiol ; 318(3): F628-F638, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31904289

RESUMO

Excessive compensatory nephron hypertrophy (CNH) has been implicated in setting the stage for progressive nephron damage. Lack of a class III phosphatidylinositol 3-kinase (Pik3c3) inhibitor suitable for using in animals and lack of a Pik3c3-deficient animal model preclude the possibility of conclusively defining a role for Pik3c3 in CNH in previous studies. Here, we report that insertion of an Frt-flanked PGK-Neo cassette into intron 19 of the mouse Pik3c3 gene resulted in a hypomorphic allele. This allowed us to create a unique mouse model and provide the first definitive genetic evidence demonstrating whether Pik3c3 is essential for the regulation of CNH. Our results indicate that homozygous Pik3c3 hypomorphic (Pik3c3Hypo/Hypo) mice express significantly low levels of Pik3c3 than heterozygous Pik3c3 hypomorphic (Pik3c3Hypo/WT) littermates, which already express a lower level of Pik3c3 than wild-type (Pik3c3WT/WT) littermates. Interestingly, after unilateral nephrectomy (UNX), Pik3c3Hypo/Hypo mice develop a significantly lower degree of CNH than Pik3c3WT/WT mice and Pik3c3Hypo/WT mice, as revealed by measurement of kidney weight, kidney-to-body weight ratio, renal protein-to-DNA ratio, and morphometric analysis of proximal tubular and glomerular size. Mechanistically, UNX-induced mammalian target of rapamycin complex 1 (mTORC1) signaling to phosphorylation of ribosomal protein S6 (rpS6) in the remaining kidney was markedly inhibited in Pik3c3 hypomorphic mice. In conclusion, the present study reports a Pik3c3 hypomorphic mouse model and provides the first definitive evidence that Pik3c3 controls the degree of compensatory nephron hypertrophy. In addition, our signaling data provide the first definitive in vivo proof that Pik3c3 functions upstream of the mTORC1-S6 kinase 1-rpS6 pathway in the regulation of compensatory nephron hypertrophy.


Assuntos
Classe III de Fosfatidilinositol 3-Quinases/metabolismo , Néfrons/patologia , Animais , Classe III de Fosfatidilinositol 3-Quinases/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , Hipertrofia , Íntrons/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Mutagênese Insercional , Nefrectomia , Néfrons/metabolismo , Transdução de Sinais/fisiologia
3.
Liver Int ; 39(8): 1504-1513, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30721562

RESUMO

BACKGROUND & AIMS: Insulin resistance is strongly associated with non-alcoholic fatty liver disease, a chronic, obesity-related liver disease. Increased endoplasmic reticulum (ER) stress plays an important role in the development of insulin resistance. In this study, we investigated the roles of miRNAs in regulating ER stress in the liver of rats with obesity. METHODS: We used miRNA microarray to determine the miRNA expression profiles in the liver of rats fed with a high fat diet (HFD). We used prediction algorithms and luciferase reporter assay to identify the target gene of miRNAs. To overexpress the miRNA miR-30b or inhibit miR-30b rats were injected with lentivirus particles containing PGLV3-miR-30b or PGLV3-miR-30b antimiR through tail vein. Hepatic steatosis was measured using transient elastography in human subjects. RESULTS: Our data showed that miR-30b was markedly up-regulated in the liver of HFD-treated rats. Bioinformatic and in vitro and in vivo studies led us to identify sarco(endo)plasmic reticulum Ca2+ -ATPase 2b (SERCA2b), as a novel target of miR-30b. Overexpression of miR-30b induced ER stress and insulin resistance in rats fed with normal diet, whereas inhibition of miR-30b by miR-30b antimiR suppressed ER stress and insulin resistance in HFD-treated rats. Finally, our data demonstrated that there was a positive correlation between serum miR-30b levels and hepatic steatosis or homoeostasis model assessment of insulin resistance (HOMA-IR) in human subjects. CONCLUSIONS: Our findings suggest that miR-30b represents not only a potential target for the treatment of insulin resistance, but also a non-invasive disease biomarker of NAFLD.


Assuntos
Estresse do Retículo Endoplasmático , Resistência à Insulina , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Animais , Gluconeogênese , Glicólise , Lipogênese , Fígado/enzimologia , Masculino , Ratos Sprague-Dawley
4.
J Nanobiotechnology ; 17(1): 95, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506085

RESUMO

BACKGROUND: It is extremely difficult to develop targeted treatments for triple-negative breast (TNB) cancer, because these cells do not express any of the key biomarkers usually exploited for this goal. RESULTS: In this work, we develop a solution in the form of a cascade responsive nanoplatform based on thermo-sensitive poly(N-vinylcaprolactam) (PNVCL)-chitosan (CS) nanoparticles (NPs). These are further modified with the cell penetrating peptide (CPP) and loaded with the chemotherapeutic drug doxorubicin (DOX). The base copolymer was optimized to undergo a phase change at the elevated temperatures of the tumor microenvironment. The acid-responsive properties of CS provide a second trigger for drug release, and the inclusion of CPP should ensure the formulations accumulate in cancerous tissue. The resultant CPP-CS-co-PNVCL NPs could self-assemble in aqueous media into spherical NPs of size < 200 nm and with low polydispersity. They are able to accommodate a high DOX loading (14.8% w/w). The NPs are found to be selectively taken up by cancerous cells both in vitro and in vivo, and result in less off-target cytotoxicity than treatment with DOX alone. In vivo experiments employing a TNB xenograft mouse model demonstrated a significant reduction in tumor volume and prolonging of life span, with no obvious systemic toxicity. CONCLUSIONS: The system developed in this work has the potential to provide new therapies for hard-to-treat cancers.


Assuntos
Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Quitosana/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Linhagem Celular , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Camundongos , Nanopartículas/química , Ratos , Ratos Wistar , Microambiente Tumoral/efeitos dos fármacos
5.
Hum Hered ; 83(2): 55-64, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29860254

RESUMO

OBJECTIVES: To estimate the prevalence and mutation types of G6PD deficiency and evaluate the relationship between G6PD genotypes and erythrocyte phenotypes in the Dai and Jingpo ethnic groups in the Dehong prefecture of the Yunnan province, China. METHODS: G6PD deficiency was screened in Dai (1,530 individuals) and Jingpo (372 individuals) populations using a modified G6PD/6PGD ratio assay. Red blood cell traits were analyzed using the Sysmex XE2100 fully automated blood analyzer. PCR-direct sequencing for G6PD genotyping analysis was performed, and then the linkage disequilibrium blocks of the target SNPs were constructed with Haploview 4.2 software. RESULTS: The prevalence of G6PD deficiency was higher in the Dai ethnic group (8.63%) than in the Jingpo ethnic group (5.91%). The major mutations in descending order were rs137852314 G>A, rs72554664 G>A, rs72554665 G>T, and rs137852341 G>T. Hemoglobin concentration was significantly lower in the rs137852314 G>A group than in the normal group (p = 0.021). Mean corpuscular volume and mean corpuscular hemoglobin were substantially higher in the rs137852341 G>T group compared to the normal group (p = 0.049, p = 0.042). A linkage disequilibrium block of 13 SNPs was constructed for the G6PD deficiency group from the Dai sample. CONCLUSIONS: The Dai and Jingpo ethnic groups have distinctive incidence rates and gene frequencies of G6PD deficiency, and the genotypes of G6PD deficiency are associated with erythrocyte phenotypes.


Assuntos
Povo Asiático/genética , Etnicidade/genética , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Deficiência de Glucosefosfato Desidrogenase/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , China/epidemiologia , Índices de Eritrócitos , Feminino , Frequência do Gene , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Prevalência , Adulto Jovem
6.
Cell Physiol Biochem ; 45(4): 1410-1422, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29462818

RESUMO

BACKGROUND/AIMS: This study aimed to investigate the mechanism by which microRNA-206 (miR-206) affects the proliferation, apoptosis, migration and invasion of osteosarcoma (OS) cells by targeting ANXA2 via the AKT signaling pathway. METHODS: A total of 132 OS tissues and 120 osteochondroma tissues were examined in this study. The targeting relationship between miR-206 and ANXA2 was verified with a dual-luciferase reporter assay. The miR-206 expression and ANXA2, AKT, PARP, FASN, Survivin, Bax, Mcl-1 and Bcl-1 mRNA and protein expression in the above two groups were examined by qRT-PCR and western blotting. The cultured OS cells were divided into 6 groups: a blank group, negative control (NC) group, miR-206 mimic group, miR-206 inhibitor group, si-ANXA2 group and miR-206 inhibitor + si-ANXA2 group. Cell cycle and apoptosis were assessed by flow cytometry, cell migration was examined with a wound-healing assay, and cell invasion was assessed with a Transwell assay. Pearson correlation analysis was used to determine the correlation between ANXA2 mRNA expression and miR-206 expression in OS. RESULTS: OS tissues exhibited increased mRNA and protein expression of ANXA2, AKT, PARP, FASN, Survivin, Mcl-1 and Bcl-2; decreased miR-206 expression; and decreased Bax mRNA and protein expression. ANXA2 mRNA expression was strongly negatively correlated with miR-206 expression in OS. ANXA2 was found to be a miR-206 target gene. In the miR-206 mimic group and the si-ANXA2 group, the mRNA and protein expression of ANXA2, AKT, PARP, FASN, Survivin, Mcl-1 and Bcl-1 decreased markedly, cell proliferation was inhibited, apoptosis was promoted, higher cell growth in G1 phase and decreased growth in S phase was detected, and decreased cell migration and invasion were observed compared with those in the blank group. CONCLUSION: The current results demonstrate that miR-206 overexpression inhibits OS cell proliferation, migration and invasion and promotes apoptosis through targeting ANXA2 by blocking the AKT signaling pathway.


Assuntos
Anexina A2/metabolismo , Neoplasias Ósseas/patologia , MicroRNAs/metabolismo , Osteossarcoma/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Adolescente , Adulto , Anexina A2/antagonistas & inibidores , Anexina A2/genética , Antagomirs/metabolismo , Apoptose , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Criança , Feminino , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Pessoa de Meia-Idade , Osteossarcoma/genética , Osteossarcoma/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Survivina , Adulto Jovem
7.
Neurochem Res ; 43(10): 1927-1937, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30167941

RESUMO

Artificial abnormal microenvironment caused by microperfusion of L-glutamate (Glu) and Ca2+ in the hippocampus results in neuron damage, which is closely related to cerebral ischemia. Ginsenoside Rb1, a compound from Panax notoginseng, was previously used to counter the artificial abnormal hippocampal environment in a microperfusion model. In addition, while the Akt/mTOR/PTEN signaling pathway has been shown to mediate neuronprotection in cerebral ischemia, whether this pathway is involved in the neuroprotection of ginsenoside Rb1 is unknown. Here SH-SY5Y cells exposed to OGD/R injury in treated with LY294002, ginsenoside Rb1, ginsenoside Rb1+ LY294002. Expressions of phosphorylation (P-)Akt/P-mTOR/P-PTEN (24 h after OGD/R) were detected by Western blotting. Effects were examined via the memory function of rats (by Morris water maze test), morphological changes in pyramidal cell (by histology), and mRNA expression (by qRT-PCR) and phosphorylation (P-) (by Western blotting and immunohistochemical staining) of Akt, P-mTOR, and P-PTEN in the hippocampus. The memory deficit of rats and pyramidal cellular necrosis and apoptosis in the CA1 region of hippocampus after microperfusion of Glu and Ca2+ were dose dependently alleviated by ginsenoside Rb1.Moreover,Western blot showed that ginsenoside Rb1 increased the expressions of P-Akt, P-mTOR and reduced P-PTEN in vivo and vitro. Thus, the potent neuroprotection of ginsenoside Rb1 in artificial abnormal microenvironment is, at least partially, related to the activation of P-AKT/P-mTOR signaling pathway and inhibition of P-PTEN protein.


Assuntos
Ginsenosídeos/farmacologia , Hipocampo/efeitos dos fármacos , PTEN Fosfo-Hidrolase/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Serina-Treonina Quinases TOR/efeitos dos fármacos , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Cromonas/farmacologia , Hipocampo/metabolismo , Masculino , Morfolinas/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
8.
Metab Brain Dis ; 33(6): 1961-1974, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30105614

RESUMO

Alzheimer's disease (AD) is a chronic neurodegenerative disorder which can contribute to memory loss and cognitive damage in the elderly; moreover, evidence from clinical and animal studies demonstrated that AD always exhibit severe cognitive deficits. However, the effects of donepezil medications on cognition are controversial. Additionally, it is unclear whether donepezil can protect neurons to improve cognitive function through the brain-derived neurotropic factor (BDNF)/tyrosine receptor kinase B (TrkB) signalling pathway in the tree shrew (TS), which has a closer evolutionary relationship to primates than rodents. Here, we designed a study on an amyloid-ß1-40 (Aß1-40)-induced TS model of AD and investigated the molecular mechanism by which donepezil protects neurons and improves cognitive function through activating the BDNF/TrkB signalling pathway. The results showed that donepezil could rescue Aß1-40-induced spatial cognition deficits, and reverse Aß1-40-induced temporal horn along with ADC enlargement in the TS brain. Meanwhile, it suppressed Aß1-40-induced neuronal damage and loss of body weight. Intriguingly, donepezil could increase the choline acetyl transferase (ChAT) expression level and reduce the fibrillary acid protein (GFAP) expression level in the hippocampus and cortex of TS. Additionally, donepezil significantly upregulated the expression level of BDNF, as well as the phosphorylated level of TrkB. These results suggested that donepezil could protect neurocytes from senility and ameliorate learning and memory impairment in the TS model of AD, which appeared to be through regulating the cholinergic system and inhibiting the BDNF/TrkB-dependent signalling pathway. Moreover, the study underlines the potency of TS to be a novel animal model for research on AD, and it deserves intensive attention.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/toxicidade , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Disfunção Cognitiva/metabolismo , Modelos Animais de Doenças , Donepezila/uso terapêutico , Fragmentos de Peptídeos/toxicidade , Receptor trkB/metabolismo , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Animais , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/tratamento farmacológico , Donepezila/farmacologia , Masculino , Nootrópicos/farmacologia , Nootrópicos/uso terapêutico , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Tupaiidae
9.
Bioorg Med Chem Lett ; 27(16): 3867-3871, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28709827

RESUMO

As shown in our previous studies, 20(R)-ginsenoside Rg3 [20(R)-Rg3] exerts a neuroprotective effect on a rat model of transient focal cerebral ischemia, and the mechanism through which it decreases the mRNA expression of calpain I and caspase-3 has been delineated. However, researchers do not know whether 20(R)-Rg3 exhibits a neuroprotective effect following oxygen-glucose deprivation and reperfusion (OGD/R) injury in vitro. In the present study, 20(R)-Rg3 increased cell viability, decreased the LDH leakage rate, and inhibited the apoptosis rate in a concentration-dependent manner. In addition, 20(R)-Rg3 markedly decreased cleaved caspase-3 protein expression. Furthermore, 20(R)-Rg3 significantly decreased the Bax mRNA and protein levels and increased the levels of Bcl-2 mRNA and protein, subsequently decreasing the Bax/Bcl-2 protein ratio. Based on these findings, 20(R)-Rg3 exerts a neuroprotective effect against OGD/R-induced apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Ginsenosídeos/farmacologia , Glucose/metabolismo , Oxigênio/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ginsenosídeos/química , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
10.
Exp Cell Res ; 347(2): 274-82, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27426724

RESUMO

Deregulation of Toll-like receptor 4 (TLR4) is closely associated with the progression of various types of cancers, but its role in pancreatic carcinogenesis is unclear. This study aimed to investigate the role of TLR4 in the angiogenesis of pancreatic cancer and the underlying molecular mechanisms. The culture supernatant (conditioned medium) of PANC-1 cells after appropriate treatment was used for the treatment of HUVECs. The proliferation, migration and tube formation of HUVECs were assessed by MTT, Transwell and Matrigel, respectively. In pancreatic cancer tissues, TLR4, VEGF and CD31 were upregulated as determined by immunohistochemistry and the expression of TLR4 and VEGF was positively correlated with microvessel density as detected by CD31 staining. Activation of TLR4 signaling by LPS in PANC-1 cells resulted in increased VEGF and phosphorylation of AKT, which were abolished by TLR4 silencing with siRNA and PI3K/AKT signaling inhibitor LY294002. The conditioned medium from PANC-1 cells treated with LY294002 or transfected with TRL4 siRNA reduced the proliferation, migration and tube formation of HUVECs. In contrast, the conditioned medium from PANC-1 cells treated with LPS stimulated the proliferation, migration and tube formation of HUVECs, which was however significantly inhibited by pretreatment of PANC-1 cells with LY294002 or transfection with TRL4 siRNA. Our findings suggest TLR4 may promote angiogenesis in pancreatic cancer by activating the PI3K/AKT signaling pathway to induce VEGF expression.


Assuntos
Neovascularização Patológica/metabolismo , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Pancreáticas/patologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , RNA Interferente Pequeno/metabolismo , Regulação para Cima/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Bioorg Med Chem Lett ; 25(3): 673-9, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25532904

RESUMO

In the present study, we investigated the antiosteoporotic effect of geraniin on osteoporosis induced by OVX in rats. The analysis of biochemical parameters showed that geraniin could significantly increase serum calcium, estradiol and calcitonin levels, and decrease serum ALP, tartrate-resistant acid phosphatase, serum crosslinked C-terminal telopeptide of type I collagen, and urinary deoxypyridinoline/creatinine ratio levels, respectively. Geraniin was also found to prevent OVX-induced bone loss in bone mineral density and bone mineral content, to elevate femur weight and bone calcium content, and to enhance the bone mechanical properties as compared with OVX group. In addition, geraniin was demonstrated to improve the histomorphological parameters of OVX-induced bone loss, including bone trabecular number, thickness, and separation. These results indicated that geraniin have a protective effect against OVX-induced rat osteoporosis.


Assuntos
Glucosídeos/uso terapêutico , Taninos Hidrolisáveis/uso terapêutico , Osteoporose/tratamento farmacológico , Fosfatase Alcalina/sangue , Animais , Densidade Óssea/efeitos dos fármacos , Calcitonina/sangue , Cálcio/sangue , Modelos Animais de Doenças , Estradiol/sangue , Feminino , Fêmur/efeitos dos fármacos , Fêmur/metabolismo , Fêmur/patologia , Glucosídeos/química , Glucosídeos/farmacologia , Taninos Hidrolisáveis/química , Taninos Hidrolisáveis/farmacologia , Osteoporose/etiologia , Ovariectomia , Ratos , Ratos Wistar
12.
Acta Biochim Biophys Sin (Shanghai) ; 47(6): 397-403, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25910576

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is associated with increased plasma homocysteine level, which is caused by down-regulation of hepatic cystathionine beta-synthase (CBS) activity. CBS catalyzes the first step in the transsulfuration of homocysteine to cysteine, which contributes ∼50% of the cysteine required for hepatic biosynthesis of glutathione (GSH), the most abundant antioxidant in cells. As the glucagon-like peptide-1 (GLP-1) receptor agonists (e.g. exendin-4) effectively reverse hepatic steatosis, the effect of exendin-4 on both homocysteine and redox status was investigated in the livers of rats fed with high-fat diet (HFD). It was found that HFD down-regulated CBS protein expression, which was probably due to induction of rno-miR-376c expression in the liver. The level of GSH was markedly reduced, whereas the level of malonydialdehyde, an indicator of lipid peroxidation, was significantly increased in the livers of rats fed with HFD. Exendin-4 treatment increased hepatic CBS protein and GSH levels, and reduced malonydialdehyde level in hyperlipidemic rats. Our findings suggest that GLP-1 receptor agonists have beneficial effects on redox homeostasis in NAFLD.


Assuntos
Dieta Hiperlipídica , Homeostase , Peptídeos/fisiologia , Animais , Cistationina beta-Sintase/genética , Cistationina beta-Sintase/metabolismo , Regulação para Baixo , Exenatida , Glutationa/metabolismo , Homocisteína/sangue , Masculino , Malondialdeído/metabolismo , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Oxirredução , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Peçonhas
13.
BMC Clin Pathol ; 14: 29, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25057261

RESUMO

BACKGROUND: A higher prevalence of chronic atrophic gastritis (CAG) occurs in younger adults in Asia. We used Stomach Age to examine the different mechanisms of CAG between younger adults and elderly individuals, and established a simple model of cancer risk that can be applied to CAG surveillance. METHODS: Stomach Age was determined by FISH examination of telomere length in stomach biopsies. Δψm was also determined by flow cytometry. Sixty volunteers were used to confirm the linear relationship between telomere length and age while 120 subjects were used to build a mathematical model by a multivariate analysis. Overall, 146 subjects were used to evaluate the validity of the model, and 1,007 subjects were used to evaluate the relationship between prognosis and Δage (calculated from the mathematical model). ROC curves were used to evaluate the relationship between prognosis and Δage and to determine the cut-off point for Δage. RESULTS: We established that a tight linear relationship between the telomere length and the age. The telomere length was obvious different between patients with and without CAG even in the same age. Δψm decreased in individuals whose Stomach Age was greater than real age, especially in younger adults. A mathematical model of Stomach Age (real age + Δage) was successfully constructed which was easy to apply in clinical work. A higher Δage was correlated with a worse outcome. The criterion of Δage >3.11 should be considered as the cut-off to select the subgroup of patients who require endoscopic surveillance. CONCLUSION: Variation in Stomach Age between individuals of the same biological age was confirmed. Attention should be paid to those with a greater Stomach Age, especially in younger adults. The Δage in the Simple Model can be used as a criterion to select CAG patients for gastric cancer surveillance.

14.
Bioorg Med Chem Lett ; 23(3): 630-4, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23290455

RESUMO

In our previous studies, geraniin was reported to have a preventive effect in the rat model of tretinoin-induced osteoporosis. However, whether geraniin exhibits an inhibitory effect on bone resorption or on MMP-9 expression is not yet known. We present here our novel findings from in vitro experiments that geraniin (a) decreases the number of mature osteoclasts and pre-osteoclast in cultures, (b) reduces the osteoclastic fusion index, and (c) inhibits the resorption areas and resorption pits. We also report that geraniin suppresses the mRNA and protein expression levels of MMP-9. These results demonstrate that geraniin has an inhibitory effect on the bone-absorption ability of osteoclasts in vitro, and the mechanisms may be closely associated with the downregulation of mRNA and protein expression of MMP-9.


Assuntos
Reabsorção Óssea , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucosídeos/farmacologia , Taninos Hidrolisáveis/farmacologia , Metaloproteinase 9 da Matriz/metabolismo , Osteoclastos/efeitos dos fármacos , Animais , Conservadores da Densidade Óssea/farmacologia , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Glucosídeos/química , Taninos Hidrolisáveis/química , Metaloproteinase 9 da Matriz/genética , Estrutura Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos
15.
Food Chem ; 405(Pt B): 135008, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36435103

RESUMO

This study aimed to mitigate the adverse effects of global warming by applying severe shoot topping (SST) to grapevines in a semi-arid climate. A three-year study (2018-2020) was performed to investigate the impact of SST on wine flavor composition. Results showed that SST effectively delayed the grape harvest date, which was more evident in the dry and warm vintage (7-11 d). SST significantly increased the concentration of myricetin-based flavonols in wines which were 18% higher than in untreated wines. Through orthogonal partial least squares discriminant analysis (OPLS-DA), SST wines were characterized by more abundant phenolic compounds and higher sensory scores. The carry-over effect of applying SST in consecutive years in the same vines could be reflected in wine color. The correlations among wine metabolites, color and aroma parameters, and sensory parameters were evaluated through multiple analyses. This study provided an idea for delaying grape ripening in a semi-arid climate.


Assuntos
Clima Desértico , Vinho , Flavonóis , Aquecimento Global , Fenóis
16.
Food Chem ; 403: 134421, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36358073

RESUMO

The cluster-zone of the fan training system with multiple trunks (F-MT) distribute >1.5 m vertically and 1.0 m horizontally, which leads to microclimate heterogeneity around clusters. In the current study, clusters were divided into eight spatial positions according to the cluster growing height and light conditions, and the aroma profiles of grapes and wines were evaluated by HS-SPME-GC-MS. Results showed that the microclimate varied in different spatial positions. Light exposure promotes the accumulation of terpenes and C13-norisoprenoids, while inhibiting C6/C9 compounds in grape berries. Zone 2 wine presented the highest global aroma concentration. Floral and fruity were the main aromas in F-MT wines, but the herbaceous was more prominent in lower-position wines. C6/C9 compounds in grapes negatively correlated with terpenes and C13-norisoprenoids in wines. In conclusion, the aroma profiles of grapes and wines varied from different cluster positions, and graded harvesting will be helpful to produce quality wines.


Assuntos
Vitis , Compostos Orgânicos Voláteis , Vinho , Vinho/análise , Norisoprenoides , Microclima , Compostos Orgânicos Voláteis/análise , Odorantes/análise , Frutas/química , Terpenos
17.
Food Chem X ; 19: 100772, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37780257

RESUMO

Recently, revealing the terroir influence on wine chemical features has drawn increasing interest. This study aimed to explain how wine flavonoid signatures were altered by vineyard parcel, harvest ripeness, vintage and bottle aging. Six commercial Cabernet Sauvignon vineyards were selected in the Manas region to produce wines at three harvest ripeness in three seasons (2019-2021) and aged for three years. The six vineyards had little difference in mesoclimate conditions while varying greatly in soil composition. Results showed high vineyard pH (> 8.5) could accelerate grape ripening rate and increase wine flavonol concentration. Vineyards with moderate nutrition produced wines with abundant anthocyanin derivatives and maintained color characteristics during aging. The role of detailed anthocyanin derivatives in regulating wine color was clarified. As the harvest ripeness elevated, wine's flavonoid profiles were altered and gained a higher red color intensity. This work provides chemical mechanisms underlying single-vineyard wines and a theoretical basis for targeted wine production.

18.
Food Res Int ; 174(Pt 1): 113508, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37986505

RESUMO

To produce premium wines in a specific region is the goal of local oenologists. This study aimed to investigate the influence of soil properties and harvest date on the volatolomics of wine to provide a better insight into single-vineyard wines. Six Cabernet Sauvignon vineyards were selected in a semi-arid region to produce their wines at three harvest ripeness levels ranging from 23°Brix-28°Brix in three seasons (2019-2021). Results showed that among all six vineyards, the vineyard with the highest soil pH produced wines with lower C6 alcohols and herbaceous aroma. Moderate nutrition in soils was beneficial for the accumulation of ß-damascenone and enhanced fruity and floral aroma in wines while over-fertile soil produced wines with the lowest sensory score. As the harvest ripeness elevated, the wine's fruity and floral aroma intensity decreased. Through advanced network analysis, the key volatiles such as ß-damascenone, ethy1 lactate, and isoamyl octanoate, and their interaction in affecting wine sensory scores were evaluated. Our study provided a concept for producing premium single-vineyard wines.


Assuntos
Vitis , Vinho , Vinho/análise , Vitis/química , Fazendas , Solo
19.
Dis Markers ; 2022: 3058354, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571612

RESUMO

Diabetes cardiomyopathy has metabolic disorder and abnormality of cardiomyocytes, which is closely related to autophagy or apoptosis of cardiomyocytes. Scutellarin (SCU) is an important monomer extracted from Erigeron breviscapus (vant.) Hand.-Mazz. This study was conducted to investigate the function of SCU on apoptosis and autophagy of myocardial cells. We established a model of type 2 diabetic cardiomyopathy by high-fat and high-sugar diet. The results indicated that SCU downregulated blood glucose, total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL) levels and upregulated high-density lipoprotein (HDL) level. In addition, SCU downregulated lactic dehydrogenase 1 (LDH1) and creatine kinase (CK) levels. Meanwhile, SCU improved the myocardium morphology and reduced myocardial apoptosis. Furthermore, SCU promoted the mRNA and protein expression of autophagy-related factors (Beclin-1 and LC3-II) and inhibited the mRNA and protein expression of apoptosis-related factors (caspase-3, caspase-8, caspase-9, caspase-12, Bax, and Cyt-C). In conclusion, SCU can promote autophagy signal pathway by upregulating the autophagy-related factors and inhibit the apoptotic signal pathway by downregulating apoptosis-related factors, thereby relieving type 2 diabetic cardiomyopathy (T2DC).


Assuntos
Diabetes Mellitus Tipo 2 , Cardiomiopatias Diabéticas , Apigenina , Apoptose , Autofagia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Cardiomiopatias Diabéticas/tratamento farmacológico , Glucuronatos , Humanos , Miócitos Cardíacos , RNA Mensageiro
20.
Front Cardiovasc Med ; 9: 869279, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571212

RESUMO

Object: Obesity is an increase in body weight beyond the limitation of skeletal and physical requirement, as the result of an excessive accumulation of fat in the body. Obesity could increase the risk of myocardial fibrosis. (-)-Epigallocatechin-3-gallate (EGCG) is the most abundant substance in green tea and has been reported to have multiple pharmacological activities. However, there is not enough evidence to show that EGCG has a therapeutic effect on obesity-induced myocardial fibrosis. This study aims to investigate whether EGCG is a potential drug for obesity-induced myocardial fibrosis. Methods: Obesity-induced myocardial fibrosis rat model was established by HFD feeding for 36 weeks. EGCG was intragastrically administered at 160 mg/kg/d for the last 4 weeks. The pathological changes of myocardial fibrosis were evaluated by tissue pathological staining and collagen quantification. Furthermore, total RNA was extracted from the heart for RNA-seq to identify the changes in the transcript profile, and the relevant hub genes were verified by quantitative real-time PCR and western blot. Results: EGCG significantly relieved HFD diet-induced obesity and alleviated the pathology of myocardial fibrosis. Biochemical analysis showed that EGCG could relieve the burden of lipid metabolism and injury to the myocardium and transcript profile analysis showed that EGCG could alleviate obesity-induced myocardial fibrosis by increasing the level of Scn5a in the heart. Furthermore, quantitative real-time PCR and western blot analysis for SCN5A also confirmed this finding. Conclusion: Taken together, these results suggest that EGCG could protect against the obesity-induced myocardial fibrosis. EGCG plays an anti-myocardial fibrosis role by regulating the expression of SCN5A in the heart.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA