Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
EMBO Mol Med ; 15(7): e17230, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37272212

RESUMO

Obesity and diabetes are risk factors for hepatocellular carcinoma (HCC); however, the underlying mechanisms are yet to be elucidated. Adeno-associated virus (AAV) frequently infects humans and has been widely used in gene therapy, but the risk of AAV infection such as HCC should be further evaluated. Here, we show that recombinant AAV injection caused liver injury, hepatic necroptosis, and HCC in db/db or high-fat diet-induced hyperglycemic and obese mice, but not in mice with only hyperglycemia or obesity. Prednisone administration or knockdown of Pebp1, highly expressed in db/db mice, alleviated hepatic injury and necroptosis induced by recombinant AAV in mice with diabetes and obesity. Inhibition of Pebp1 pathway also attenuated inflammation and necroptosis in vitro. Our findings show that AAV infection is a critical risk factor for HCC in patients with diabetes and obesity, and AAV gene therapy for these patients should be carefully evaluated. Both prednisone treatment and targeting Pebp1 pathway are promising strategies to alleviate inflammation and necroptosis that occurred in AAV gene therapy or related diseases.


Assuntos
Carcinoma Hepatocelular , Diabetes Mellitus , Neoplasias Hepáticas , Humanos , Camundongos , Animais , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/terapia , Camundongos Obesos , Dependovirus/genética , Neoplasias Hepáticas/terapia , Necroptose , Prednisona , Obesidade/complicações , Inflamação , Camundongos Endogâmicos C57BL
2.
Sci China Life Sci ; 66(1): 127-136, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35907113

RESUMO

Phenylketonuria (PKU), a disease resulting in the disability to degrade phenylalanine (Phe) is an inborn error with a 1 in 10,000 morbidity rate on average around the world which leads to neurotoxicity. As an potential alternative to a protein-restricted diet, oral intake of engineered probiotics degrading Phe inside the body is a promising treatment, currently at clinical stage II (Isabella, et al., 2018). However, limited transmembrane transport of Phe is a bottleneck to further improvement of the probiotic's activity. Here, we achieved simultaneous degradation of Phe both intracellularly and extracellularly by expressing genes encoding the Phe-metabolizing enzyme phenylalanine ammonia lyase (PAL) as an intracellularly free and a cell surface-immobilized enzyme in Escherichia coli Nissle 1917 (EcN) which overcomes the transportation problem. The metabolic engineering strategy was also combined with strengthening of Phe transportation, transportation of PAL-catalyzed trans-cinnamic acid and fixation of released ammonia. Administration of our final synthetic strain TYS8500 with PAL both displayed on the cell surface and expressed inside the cell to the PahF263S PKU mouse model reduced blood Phe concentration by 44.4% compared to the control EcN, independent of dietary protein intake. TYS8500 shows great potential in future applications for PKU therapy.


Assuntos
Microbioma Gastrointestinal , Fenilcetonúrias , Animais , Camundongos , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo , Enzimas Imobilizadas/uso terapêutico , Proteínas Alimentares , Fenilcetonúrias/terapia , Fenilcetonúrias/genética , Fenilcetonúrias/metabolismo , Fenilalanina/metabolismo , Fenilalanina/uso terapêutico
3.
Nat Metab ; 4(12): 1713-1731, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36456724

RESUMO

Dietary restriction is widely used to reduce fat mass and lose weight in individuals with or without obesity; however, weight regain after dieting is still a big challenge, and the underlying mechanisms remain largely elusive. Here we show that refeeding after various types of dieting induces quick fat accumulation in mice and enhanced intestinal lipid absorption contributes to post-dieting fat mass increase. Moreover, refeeding after short-term dietary restriction is accompanied by an increase in intestinal Lactobacillus and its metabolites, which contributes to enhanced intestinal lipid absorption and post-dieting fat mass increase; however, refeeding a high-protein diet after short-term dietary restriction attenuates intestinal lipid absorption and represses fat accumulation by preventing Lactobacillus growth. Our results provide insight into the mechanisms underlying fat mass increase after dieting. We also propose that targeting intestinal Lactobacillus to inhibit intestinal lipid absorption via high-protein diet or antibiotics is likely an effective strategy to prevent obesity after dieting.


Assuntos
Dieta Rica em Proteínas , Lactobacillus , Camundongos , Animais , Obesidade/prevenção & controle , Obesidade/metabolismo , Lipídeos
4.
J Inflamm Res ; 15: 5635-5648, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211223

RESUMO

Background: Sustained inflammation is implicated in a variety of pathological conditions like infection, obesity and type 2 diabetes. Lipid metabolism is crucial to support immune response during infection of bacteria. However, how sustained inflammation affects lipid metabolism, especially in white adipose tissue remains largely unknown. Methods: Sustained inflammation was induced by daily injection of Lipopolysaccharide (LPS). Tlr4 knockout mice were used to study the mechanism. Inflammation and lipid metabolism were evaluated by quantitative PCR, white blood cell counting, nuclear magnetic resonance, fat cell size quantification, lipolysis and fatty acid uptake assays, respiratory exchange ratio, and energy expenditure. Results: Here, we found that sustained inflammation leads to fat loss in mice with a quick loss and gradual increase manner. Moreover, LPS injection leads to inflammation, anorexia, decreased lipid anabolism, and increased lipid catabolism. Mechanically, we show that LPS induces fat loss, inflammation, anorexia, and alteration of lipid metabolism mainly dependent on Tlr4. Interestingly, sustained inflammation induces less fat loss, especially in epididymal white adipose tissue, than pair-feeding, and pair-feeding has no significant effect on inflammation and leads to less fatty acid uptake, more lipid catabolism and energy expenditure than LPS injection. In addition, we demonstrate that short-term sustained inflammation leads to relative long-term tolerance for LPS-induced anorexia, inflammation and altered lipid metabolism. Conclusion: These findings demonstrate that sustained inflammation induced by LPS leads to tolerable anorexia and fat loss via Tlr4 in mice, and provide new insights into the effect of sustained inflammation on lipid metabolism and subsequent tolerance.

5.
Diabetes ; 68(11): 2120-2130, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31439642

RESUMO

Diabetic peripheral neuropathy (DPN) is the most common complication in both type 1 and type 2 diabetes, but any treatment toward the development of DPN is not yet available. Axon degeneration is an early feature of many peripheral neuropathies, including DPN. Delay of axon degeneration has beneficial effects on various neurodegenerative diseases, but its effect on DPN is yet to be elucidated. Deficiency of Sarm1 significantly attenuates axon degeneration in several models, but the effect of Sarm1 deficiency on DPN is still unclear. In this study, we show that Sarm1 knockout mice exhibit normal glucose metabolism and pain sensitivity, and deletion of the Sarm1 gene alleviates hypoalgesia in streptozotocin-induced diabetic mice. Moreover, Sarm1 gene deficiency attenuates intraepidermal nerve fiber loss in footpad skin; alleviates axon degeneration, the change of g-ratio in sciatic nerves, and NAD+ decrease; and relieves axonal outgrowth retardation of dorsal root ganglia from diabetic mice. In addition, Sarm1 gene deficiency markedly diminishes the changes of gene expression profile induced by streptozotocin in the sciatic nerve, especially some abundant genes involved in neurodegenerative diseases. These findings demonstrate that Sarm1 gene deficiency attenuates DPN in mice and suggest that slowing down axon degeneration is a potential promising strategy to combat DPN.


Assuntos
Proteínas do Domínio Armadillo/genética , Proteínas do Citoesqueleto/genética , Diabetes Mellitus Experimental/genética , Neuropatias Diabéticas/genética , Doenças do Sistema Nervoso Periférico/genética , Animais , Proteínas do Domínio Armadillo/metabolismo , Axônios/metabolismo , Proteínas do Citoesqueleto/metabolismo , Diabetes Mellitus Experimental/metabolismo , Neuropatias Diabéticas/metabolismo , Gânglios Espinais/metabolismo , Masculino , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Doenças do Sistema Nervoso Periférico/metabolismo
6.
FEBS Lett ; 592(19): 3305-3316, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30192985

RESUMO

Short-term tamoxifen treatment has effects on lipid and glucose metabolism in mice fed chow. However, its effects on metabolism in mice fed high-fat diet (HFD) and the underlying mechanisms are unclear. Here, we show that tamoxifen treatment for 5 days decreases fat mass for as long as 18 weeks in mice fed HFD. Tamoxifen alters mRNA levels of some genes involved in lipid metabolism in white adipose tissue and improves glucose and insulin tolerance as well as hepatic insulin signaling for 12-20 weeks. Proopiomelanocortin (POMC) neuron-specific deletion of nicotinamide mononucleotide adenylyltransferase 2 (Nmnat2) attenuates the effects of tamoxifen on glucose and insulin tolerance. These data demonstrate that short-term injection of tamoxifen has long-term effects on lipid and glucose metabolism in HFD mice with involvement of Nmnat2 in POMC neurons.


Assuntos
Neurônios/efeitos dos fármacos , Nicotinamida-Nucleotídeo Adenililtransferase/metabolismo , Pró-Opiomelanocortina/metabolismo , Tamoxifeno/farmacologia , Animais , Antineoplásicos Hormonais/farmacologia , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Resistência à Insulina/genética , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Neurônios/metabolismo , Nicotinamida-Nucleotídeo Adenililtransferase/genética , Obesidade/etiologia , Obesidade/genética , Obesidade/metabolismo , Pró-Opiomelanocortina/genética , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...