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1.
J Med Virol ; 95(8): e29035, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37605995

RESUMO

Recombinant LL-37 Lactococcus lactis (Oral LL-37) was designed to prevent progression of COVID-19 by targeting virus envelope, however, effectiveness and safety of Oral LL-37 in clinical application was unclear. A total of 238 adult inpatients, open-labelled, randomized, placebo-controlled, single-center study was conducted to investigate the primary end points, including negative conversion time (NCT) of SARS-CoV-2 RNA and adverse events (AEs). As early as intervened on 6th day of case confirmed, Oral LL-37 could significantly shorten NCT (LL-37 9.80 ± 2.67 vs. placebo 14.04 ± 5.89, p < 0.01). For Oral LL-37, as early as treated in 6 days, the adjusted hazard ratio (HR) for a primary event of nucleic acid negative outcome was 6.27-fold higher than 7-day-later (HR: 6.276, 95% confidence interval [CI]: 3.631-10.848, p < 0.0001), and the adjusted HR of Oral LL-37 within 6 days is higher than placebo (HR: 2.427 95% CI: 1.239-4.751, p = 0.0097). No severe AEs were observed during hospitalization and follow-up investigation. This study shows that early intervention of Oral LL-37 incredibly reduces NCT implying a potential for clearance of Omicron BA.5.1.3 without evident safety concerns.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Humanos , COVID-19/prevenção & controle , RNA Viral , Hospitalização , Pacientes Internados
2.
Am J Physiol Endocrinol Metab ; 323(1): E69-E79, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35575231

RESUMO

Brown adipose tissue (BAT) is the primary site of adaptive thermogenesis, which is involved in energy expenditure and has received much attention in the field of obesity treatment. By screening a small-molecule compound library of drugs approved by the Food and Drug Administration, pantothenic acid was identified as being able to significantly upregulate the expression of uncoupling protein 1 (UCP1), a key thermogenic protein found in BAT. Pantothenate (PA) treatment decreased adiposity, reversed hepatic steatosis, and improved glucose homeostasis by increasing energy expenditure in C57BL/6J mice fed a high-fat diet. PA also significantly increased BAT activity and induced beige adipocytes formation. Mechanistically, the beneficial effects were mediated by UCP1 because PA treatment was unable to ameliorate obesity in UCP1 knockout mice. In conclusion, we identified PA as an effective BAT activator that can prevent obesity and may represent a promising strategy for the clinical treatment of obesity and related metabolic diseases.NEW & NOTEWORTHY PA treatment effectively and safely protected against obesity via the BAT-UCP1 axis. PA has therapeutic potential for treating obesity and type II diabetes.


Assuntos
Tecido Adiposo Marrom , Diabetes Mellitus Tipo 2 , Tecido Adiposo Marrom/metabolismo , Animais , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Metabolismo Energético , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Termogênese , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
3.
Biotechnol Lett ; 44(10): 1149-1162, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36006576

RESUMO

OBJECTIVES: We constructed a recombinant oral GLP-1 analogue in Lactococcus lactis (L. lactis) and evaluated its physiological functions. RESULTS: In silico docking suggested the alanine at position 8 substituted with serine (A8SGLP-1) reduced binding of DPP4, which translated to reduced cleavage by DPP4 with minimal changes in stability. This was further confirmed by an in vitro enzymatic assay which showed that A8SGLP-1 significantly increased half-life upon DPP4 treatment. In addition, recombinant L. lactis (LL-A8SGLP-1) demonstrated reduced fat mass with no changes in body weight, significant improvement of random glycemic control and reduced systemic inflammation compared with WT GLP-1 in db/db mice. CONCLUSION: LL-A8SGLP-1 adopted in live biotherapeutic products reduce blood glucose in db/db mice without affecting its function.


Assuntos
Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Alanina/uso terapêutico , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Dipeptidil Peptidase 4/metabolismo , Dipeptidil Peptidase 4/uso terapêutico , Peptídeo 1 Semelhante ao Glucagon/genética , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Intolerância à Glucose/tratamento farmacológico , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Serina
4.
Biol Reprod ; 104(5): 1154-1161, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33590844

RESUMO

Sperm quality is an important indicator of male fertility, and a suitable biomarker enables the selection of high-quality spermatozoa. We previously found that L-amino acid oxidase encoded by the L-amino acid oxidase 1 (Lao1) gene exerts biological roles in the mammary gland and brain by converting specific L-amino acids into keto acids, ammonia, and hydrogen peroxide (H2O2). Here, we describe the role of Lao1 in male reproduction. Lao1-deficient (Lao1-/-) male mice generated fewer pregnant embryos and pups as well as lower ratios of fertilized oocytes and even ovulated number was not different, suggesting that male subfertility caused the smaller litters. We found that LAO1 expressed in acrosomes is associated with high malformation ratios and low viability of Lao1-/- sperm. Wild-type (WT) sperm produced more H2O2 than Lao1-/- sperm, and 10 µM H2O2 restored knockout (KO) sperm viability in vitro. In addition, the sperm ratio of induced acrosome reaction was higher in WT than in Lao1-/- sperm incubated with the calcium ionophore A23187. Moreover, LAO1 expression was abundant in bovine sperm with high fertilization ratios. We concluded that LAO1 localized in the sperm acrosome influences sperm viability and morphology as well as the acrosome reaction, and that LAO1-deficient sperm might cause male subfertility. Thus, LAO1 might serve as a novel marker for selecting high-quality spermatozoa, especially for livestock reproduction.


Assuntos
L-Aminoácido Oxidase/genética , Reprodução/genética , Espermatozoides/enzimologia , Animais , Bovinos , L-Aminoácido Oxidase/metabolismo , Masculino , Camundongos
5.
Appl Microbiol Biotechnol ; 105(14-15): 6007-6018, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34390354

RESUMO

Liver fibrosis is caused by the accumulation of extracellular matrix proteins on the surface of hepatocytes and results from chronic liver injury. TGFß1 is one of the most important promoters of hepatic fibrosis, which accelerates the transformation of hepatic stellate cells to myofibroblasts and collagen expression. It is well-known that TGFß1 binds to TGFßR2 to mediate its downstream signal cascades to regulate target gene transcription. Therefore, the TGFßR2 blocker might be a prominent drug candidate. We constructed TGFßR2 extracellular domain into living biotherapeutics Lactococcus lactis to reduce hepatic fibrosis in CCl4 treated mice in the present study. We found that the culture supernatant of the recombinant bacteria can inhibit the TGFß1-induced collagen synthesis in the hepatic stellate cells at the cellular level. In addition, results of in vivo study showed that the recombinant bacteria significantly reduced the degree of liver fibrosis in CCl4-treated mice. Furthermore, flow cytometry results indicated that the recombinant bacteria treatment significantly reduced the CD11b+ Kupffer cells compared with the empty vector bacteria group. Consistently, fibrosis-related gene and protein expression were significantly reduced upon recombinant bacteria treatment. Finally, the subchronic toxicity test results showed that this bacteria strain did not have any significant side effects. In conclusion, our recombinant Lactococcus lactis shows tremendous therapeutic potential in liver fibrosis. KEY POINTS: • The supernatant of L. lactis expressing TGFßR2 inhibits the activation of myofibroblast. • The oral recombinant strain reduced the degree of liver fibrosis and inflammation in mice. • The recombinant strain was safe in subchronic toxicity test in mice.


Assuntos
Lactococcus lactis , Animais , Colágeno , Hepatócitos , Lactococcus lactis/genética , Cirrose Hepática/prevenção & controle , Camundongos
6.
Gut ; 69(7): 1239-1247, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31744910

RESUMO

OBJECTIVE: Dietary fibre has beneficial effects on energy metabolism, and the majority of studies have focused on short-chain fatty acids produced by gut microbiota. Ginseng has been reported to aid in body weight management, however, its mechanism of action is not yet clear. In this study, we focused on the potential modulating effect of ginseng on gut microbiota, aiming to identify specific strains and their metabolites, especially long-chain fatty acids (LCFA), which mediate the anti-obesity effects of ginseng. DESIGN: Db/db mice were gavaged with ginseng extract (GE) and the effects of GE on gut microbiota were evaluated using 16S rDNA-based high throughput sequencing. To confirm the candidate fatty acids, untargeted metabolomics analyses of the serum and medium samples were performed. RESULTS: We demonstrated that GE can induce Enterococcus faecalis, which can produce an unsaturated LCFA, myristoleic acid (MA). Our results indicate that E. faecalis and its metabolite MA can reduce adiposity by brown adipose tissue (BAT) activation and beige fat formation. In addition, the gene of E. faecalis encoding Acyl-CoA thioesterases (ACOTs) exhibited the biosynthetic potential to synthesise MA, as knockdown (KD) of the ACOT gene by CRISPR-dCas9 significantly reduced MA production. Furthermore, exogenous treatment with KD E. faecalis could not reproduce the beneficial effects of wild type E. faecalis, which work by augmenting the circulating MA levels. CONCLUSIONS: Our results demonstrated that the gut microbiota-LCFA-BAT axis plays an important role in host metabolism, which may provide a strategic advantage for the next generation of anti-obesity drug development.


Assuntos
Tecido Adiposo Marrom/metabolismo , Enterococcus faecalis/metabolismo , Ácidos Graxos Monoinsaturados/metabolismo , Obesidade/metabolismo , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Panax , Extratos Vegetais/farmacologia , RNA Ribossômico 16S/genética
7.
FASEB J ; 33(3): 3343-3352, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30433825

RESUMO

The development of gut microbiota during infancy is an important event that affects the health status of the host; however, the mechanism governing it is not fully understood. l-Amino acid oxidase 1 (LAO1) is a flavoprotein that catalyzes the oxidative deamination of particular l-amino acids and converts them into keto acids, ammonia, and H2O2. Our previous study showed that LAO1 is present in mouse milk and exerts protection against bacteria by its production of H2O2. The data led us to consider whether LAO1, H2O2, or both could impact infant gut microbiota development via mother's milk consumption in mice. Different gut microbiota profiles were observed in the wild-type (WT) and LAO1-knockout mouse pups. The WT pups' microbiota was relatively simple and composed of only a few dominant bacteria, such as Lactobacillus, whereas the lactating knockout pups had high microbiota diversity. Cross-fostering experiments indicated that WT milk (containing LAO1) has the ability to suppress the diversity of microbiota in pups. We observed that the stomach content of pups fed WT milk had LAO1 proteins and the ability to produce H2O2. Moreover, culture experiments showed that Lactobacillus was abundant in the feces of pups fed WT milk and that Lactobacillus was more resistant to H2O2 than Bifidobacterium and Escherichia. Human breast milk produces very little H2O2, which could be the reason for Lactobacillus not being dominant in the feces of breast-fed human infants. In mouse mother's milk, H2O2 is generated from the process of free amino acid metabolism, and H2O2 may be a key player in regulating the initial acquisition and development of gut microbiota, especially growth of Lactobacillus, during infancy.-Shigeno, Y., Zhang, H., Banno, T., Usuda, K., Nochi, T., Inoue, R., Watanabe, G., Jin, W., Benno, Y., Nagaoka, K. Gut microbiota development in mice is affected by hydrogen peroxide produced from amino acid metabolism during lactation.


Assuntos
Aminoácidos/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Lactação/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Animais , Bifidobacterium/efeitos dos fármacos , Fezes/microbiologia , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Lactação/metabolismo , Lactobacillus/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Leite/microbiologia , Probióticos/administração & dosagem
8.
Proc Natl Acad Sci U S A ; 114(45): E9474-E9482, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29078316

RESUMO

Uncoupling protein 1 (UCP1) is localized on the inner mitochondrial membrane and generates heat by uncoupling ATP synthesis from proton transit across the inner membrane. UCP1 is a key element of nonshivering thermogenesis and is most likely important in the regulation of body adiposity. Pigs (Artiodactyl family Suidae) lack a functional UCP1 gene, resulting in poor thermoregulation and susceptibility to cold, which is an economic and pig welfare issue owing to neonatal mortality. Pigs also have a tendency toward fat accumulation, which may be linked to their lack of UCP1, and thus influences the efficiency of pig production. Here, we report application of a CRISPR/Cas9-mediated, homologous recombination (HR)-independent approach to efficiently insert mouse adiponectin-UCP1 into the porcine endogenous UCP1 locus. The resultant UCP1 knock-in (KI) pigs showed an improved ability to maintain body temperature during acute cold exposure, but they did not have alterations in physical activity levels or total daily energy expenditure (DEE). Furthermore, ectopic UCP1 expression in white adipose tissue (WAT) dramatically decreased fat deposition by 4.89% (P < 0.01), consequently increasing carcass lean percentage (CLP; P < 0.05). Mechanism studies indicated that the loss of fat upon UCP1 activation in WAT was linked to elevated lipolysis. UCP1 KI pigs are a potentially valuable resource for agricultural production through their combination of cold adaptation, which improves pig welfare and reduces economic losses, with reduced fat deposition and increased lean meat production.


Assuntos
Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/fisiologia , Sistemas CRISPR-Cas/fisiologia , Termogênese/fisiologia , Proteína Desacopladora 1/metabolismo , Adiposidade/fisiologia , Animais , Temperatura Corporal/fisiologia , Regulação da Temperatura Corporal/fisiologia , Temperatura Baixa , Metabolismo Energético/fisiologia , Feminino , Lipólise/fisiologia , Masculino , Camundongos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Suínos
9.
Proc Natl Acad Sci U S A ; 113(10): 2708-13, 2016 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-26903641

RESUMO

Polycystic ovary syndrome (PCOS), which is characterized by anovulation, hyperandrogenism, and polycystic ovaries, is a complex endocrinopathy. Because the cause of PCOS at the molecular level is largely unknown, there is no cure or specific treatment for PCOS. Here, we show that transplantation of brown adipose tissue (BAT) reversed anovulation, hyperandrogenism, and polycystic ovaries in a dehydroepiandrosterone (DHEA)-induced PCOS rat. BAT transplantation into a PCOS rat significantly stabilized menstrual irregularity and improved systemic insulin sensitivity up to a normal level, which was not shown in a sham-operated or muscle-transplanted PCOS rat. Moreover, BAT transplantation, not sham operation or muscle transplantation, surprisingly improved fertility in PCOS rats. Interestingly, BAT transplantation activated endogenous BAT and thereby increased the circulating level of adiponectin, which plays a prominent role in whole-body energy metabolism and ovarian physiology. Consistent with BAT transplantation, administration of adiponectin protein dramatically rescued DHEA-induced PCOS phenotypes. These results highlight that endogenous BAT activity is closely related to the development of PCOS phenotypes and that BAT activation might be a promising therapeutic option for the treatment of PCOS.


Assuntos
Tecido Adiposo Marrom/transplante , Infertilidade Feminina/cirurgia , Resistência à Insulina , Síndrome do Ovário Policístico/cirurgia , Adiponectina/sangue , Adiponectina/farmacologia , Adulto , Análise de Variância , Animais , Glicemia/metabolismo , Desidroepiandrosterona , Metabolismo Energético/efeitos dos fármacos , Ciclo Estral/efeitos dos fármacos , Feminino , Humanos , Insulina/sangue , Masculino , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/metabolismo , Ratos Sprague-Dawley , Resultado do Tratamento
10.
Int J Mol Sci ; 20(7)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939798

RESUMO

Brown adipose tissue (BAT), an organ that burns energy through uncoupling thermogenesis, is a promising therapeutic target for obesity. However, there are still no safe anti-obesity drugs that target BAT in the market. In the current study, we performed large scale screening of 636 compounds which were approved by Food and Drug Administration (FDA) to find drugs that could significantly increase uncoupling protein 1 (UCP1) mRNA expression by real-time PCR. Among those UCP1 activators, most of them were antibiotics or carcinogenic compounds. We paid particular attention to fluvastatin sodium (FS), because as an inhibitor of the cellular hydroxymethyl glutaryl coenzyme A (HMG-CoA) reductase, FS has already been approved for treatment of hypercholesteremia. We found that in the cellular levels, FS treatment significantly increased UCP1 expression and BAT activity in human brown adipocytes. Consistently, the expression of oxidative phosphorylation-related genes was significantly increased upon FS treatment without differences in adipogenic gene expression. Furthermore, FS treatment resisted to high-fat diet (HFD)-induced body weight gain by activating BAT in the mice model. In addition, administration of FS significantly increased energy expenditure, improved glucose homeostasis and ameliorated hepatic steatosis. Furthermore, we reveal that FS induced browning in subcutaneous white adipose tissue (sWAT) known to have a beneficial effect on energy metabolism. Taken together, our results clearly demonstrate that as an effective BAT activator, FS may have great potential for treatment of obesity and related metabolic disorders.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Fármacos Antiobesidade/uso terapêutico , Fluvastatina/uso terapêutico , Obesidade/tratamento farmacológico , Tecido Adiposo Marrom/metabolismo , Animais , Fármacos Antiobesidade/farmacologia , Células Cultivadas , Metabolismo Energético , Fluvastatina/farmacologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
11.
J Cell Mol Med ; 22(1): 101-110, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28816006

RESUMO

It has been recently reported that CD38 was highly expressed in adipose tissues from obese people and CD38-deficient mice were resistant to high-fat diet (HFD)-induced obesity. However, the role of CD38 in the regulation of adipogenesis and lipogenesis is unknown. In this study, to explore the roles of CD38 in adipogenesis and lipogenesis in vivo and in vitro, obesity models were generated with male CD38-/- and WT mice fed with HFD. The adipocyte differentiations were induced with MEFs from WT and CD38-/- mice, 3T3-L1 and C3H10T1/2 cells in vitro. The lipid accumulations and the alternations of CD38 and the genes involved in adipogenesis and lipogenesis were determined with the adipose tissues from the HFD-fed mice or the MEFs, 3T3-L1 and C3H10T1/2 cells during induction of adipocyte differentiation. The results showed that CD38-/- male mice were significantly resistant to HFD-induced obesity. CD38 expressions in adipocytes were significantly increased in WT mice fed with HFD, and the similar results were obtained from WT MEFs, 3T3-L1 and C3H10T1/2 during induction of adipocyte differentiation. The expressions of PPARγ, AP2 and C/EBPα were markedly attenuated in adipocytes from HFD-fed CD38-/- mice and CD38-/- MEFs at late stage of adipocyte differentiation. Moreover, the expressions of SREBP1 and FASN were also significantly decreased in CD38-/- MEFs. Finally, the CD38 deficiency-mediated activations of Sirt1 signalling were up-regulated or down-regulated by resveratrol and nicotinamide, respectively. These results suggest that CD38 deficiency impairs adipogenesis and lipogenesis through activating Sirt1/PPARγ-FASN signalling pathway during the development of obesity.


Assuntos
ADP-Ribosil Ciclase 1/deficiência , Adipogenia , Tecido Adiposo/metabolismo , Lipogênese , PPAR gama/metabolismo , Transdução de Sinais , Sirtuína 1/metabolismo , ADP-Ribosil Ciclase 1/metabolismo , Adipócitos/metabolismo , Animais , Diferenciação Celular , Embrião de Mamíferos/citologia , Fibroblastos/metabolismo , Camundongos , NAD/metabolismo
12.
Biochem Biophys Res Commun ; 501(3): 807-813, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29775611

RESUMO

The strong effects of classic brown adipose tissue (BAT) and recruited beige adipocytes in treatment of obesity and metabolic syndrome have been attracting increasing research interest. Cold treatment is an effective, convenient approach to stimulate BAT activity and induce white adipose tissue (WAT) browning. Here, we utilized prolonged cold exposure (from 2 h to 2 weeks in a 4° cold chamber) to elucidate dynamic changes in BAT and in WAT browning during acute and chronic cold exposure in mice. BAT mass decreased quickly, with reduced lipid droplet sizes within 8 h of cold exposure owing to the utilization of BAT pre-storage triglycerides, and subsequently increased during prolonged cold exposure. These dynamic morphological changes in BAT were confirmed by gene expression changes in ADRB3 and PGC1α, while UCP1 and ELOVL3 expression was continuously up-regulated throughout the entire cold exposure period. Additionally, cold treatment increased BAT secretion of FGF21, which has been reported to activate beige adipocyte formation. Thus, to illustrate potential crosstalk between secreted BAT proteins (so-called BATokines) and beige adipogenesis during cold stress, we performed an interscapular BAT (iBAT) removal experiment in mice. Surprisingly, loss of classic iBAT enhanced WAT browning due to compensatorily increased sympathetic WAT input. Unexpectedly, we observed significantly reduced adiposity in the iBAT removal group compared with the control group. These results further suggest that WAT browning plays an important role in whole-body energy metabolism during cold acclimation, even without iBAT. Furthermore, our data imply that enhanced WAT browning may be an efficient therapeutic tool to combat obesity and related syndromes.


Assuntos
Tecido Adiposo Marrom/fisiologia , Tecido Adiposo Branco/fisiologia , Adiposidade , Resposta ao Choque Frio , Tecido Adiposo Marrom/cirurgia , Animais , Metabolismo Energético , Masculino , Camundongos Endogâmicos C57BL , Obesidade/terapia , Termogênese , Transcriptoma
13.
FASEB J ; 31(1): 333-345, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28049156

RESUMO

Increasing energy expenditure through activation of brown adipose tissue (BAT) is a critical approach to treating obesity and diabetes. In this study, rutin, a natural compound extracted from mulberry and a drug used as a capillary stabilizer clinically for many years without any side effects, regulated whole-body energy metabolism by enhancing BAT activity. Rutin treatment significantly reduced adiposity, increased energy expenditure, and improved glucose homeostasis in both genetically obese (Db/Db) and diet-induced obesity (DIO) mice. Rutin also induced brown-like adipocyte (beige) formation in subcutaneous adipose tissue in both obesity mouse models. Mechanistically, we found that rutin directly bound to and stabilized SIRT1, leading to hypoacetylation of peroxisome proliferator-activated receptor γ coactivator-1α protein, which stimulated Tfam transactivation and eventually augmented the number of mitochondria and UCP1 activity in BAT. These findings reveal that rutin is a novel small molecule that activates BAT and may provide a novel therapeutic approach to the treatment of metabolic disorders.-Yuan, X., Wei, G., You, Y., Huang, Y., Lee, H. J., Dong, M., Lin, J., Hu, T., Zhang, H., Zhang, C., Zhou, H., Ye, R., Qi, X., Zhai, B., Huang, W., Liu, S., Xie, W., Liu, Q., Liu, X., Cui, C., Li, D., Zhan, J., Cheng, J., Yuan, Z., Jin, W. Rutin ameliorates obesity through brown fat activation.


Assuntos
Tecido Adiposo Marrom/fisiologia , Dieta Hiperlipídica/efeitos adversos , Metabolismo Energético/efeitos dos fármacos , Obesidade/tratamento farmacológico , Rutina/farmacologia , Animais , Regulação da Temperatura Corporal/efeitos dos fármacos , Regulação da Temperatura Corporal/fisiologia , Temperatura Baixa , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Teste de Tolerância a Glucose , Células HEK293 , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , Camundongos , Camundongos Obesos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
14.
Liver Int ; 38(5): 803-812, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28898508

RESUMO

BACKGROUND & AIMS: Hepatic steatosis is a common feature of patients with chronic hepatitis C. Previous reports have shown that the overexpression of hepatitis C virus core-encoding sequences (hepatitis C virus genotypes 3a and 1b) significantly induces intracellular triglyceride accumulation. However, the underlying mechanism has not yet been revealed. METHODS: To investigate whether Sirt1 is involved in hepatitis C virus-mediated hepatic steatosis, the overexpression of hepatitis C virus core 1b protein and Sirt1 and the knockdown of Sirt1 in HepG2 cells were performed. To confirm the results of the cellular experiment liver-specific Sirt1 KO mice with lentivirus-mediated hepatitis C virus core 1b overexpression were studied. RESULTS: Our results show that hepatitis C virus core 1b protein overexpression led to the accumulation of triglycerides in HepG2 cells. Notably the expression of PPARγ2 was dramatically increased at both the mRNA and protein levels by hepatitis C virus core 1b overexpression. The protein expression of Sirt1 is an upstream regulator of PPARγ2 and was also significantly increased after core 1b overexpression. In addition, the overexpression or knockdown of Sirt1 expression alone was sufficient to modulate p300-mediated PPARγ2 deacetylation. In vivo studies showed that hepatitis C virus core protein 1b-induced hepatic steatosis was attenuated in liver-specific Sirt1 KO mice by downregulation of PPARγ2 expression. CONCLUSIONS: Sirt1 mediates hepatitis C virus core protein 1b-induced hepatic steatosis by regulation of PPARγ2 expression.


Assuntos
Fígado Gorduroso/metabolismo , Fígado/patologia , Sirtuína 1/genética , Proteínas do Core Viral/metabolismo , Animais , Fígado Gorduroso/genética , Fígado Gorduroso/virologia , Expressão Gênica , Células Hep G2 , Hepacivirus , Hepatite C Crônica/complicações , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Triglicerídeos/metabolismo
15.
Eur J Nutr ; 57(1): 391-403, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28439667

RESUMO

PURPOSE: Myricetin, a dietary flavonoid, is effective in the treatment of obesity and insulin resistance by increasing glucose transport and lipogenesis in adipocyte and diminishing systemic inflammation in obesity. However, it has not been revealed yet whether myricetin is associated with brown adipose tissue (BAT) activation that tightly mediates systemic energy metabolism. Therefore, this study assessed whether myricetin activated brown adipose tissue in db/db mouse. METHODS: Myricetin (400 mg/kg) in distilled water was fed daily by oral gavage to leptin receptor-deficient db/db male mice at 4 weeks of age for 14 weeks. Body weight change, glucose intolerance test, blood lipid profile and BAT activation using PET-CT were assessed. RESULTS: After myricetin treatment for 14 weeks, systemic insulin resistance and hepatic steatosis were significantly improved in db/db mice with body weight reduction and myricetin led to decreased adipocity, improved plasma lipid profiles and increased energy expenditure. Myricetin activated BAT by upregulating thermogenic protein expression and activating mitochondrial biogenesis, eventually increasing heat dissipation in skin after cold exposure. In iWAT, myricetin induced beige formation, increased thermogenic protein expression and activated mitochondrial biogenesis. Consistently, thermogenic gene expression was upregulated when myricetin was introduced in C3H10T1/2 cells during brown adipocytes differentiation. Moreover, the expression level of adiponectin was significantly increased in C3H10T1/2 cells, adipose tissues and plasma after myricetin treatment. CONCLUSIONS: These results highlight that myricetin prevents obesity and systemic insulin resistance by activating BAT and increasing adiponectin expression in BAT.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/fisiologia , Flavonoides/administração & dosagem , Resistência à Insulina , Obesidade/prevenção & controle , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adiponectina/genética , Animais , Metabolismo Energético/efeitos dos fármacos , Fígado Gorduroso/prevenção & controle , Expressão Gênica/efeitos dos fármacos , Hiperlipidemias/prevenção & controle , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Receptores para Leptina/deficiência , Termogênese/efeitos dos fármacos , Termogênese/genética , Aumento de Peso
16.
Diabetologia ; 60(5): 900-910, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28074253

RESUMO

AIMS/HYPOTHESIS: High-energy diets are among the main causes of the global epidemic of metabolic disorders, including obesity and type 2 diabetes. The mechanisms of high-energy-diet-induced metabolic disorders are complex and largely unknown. The non-receptor tyrosine kinase c-Abl plays an important role in adipogenesis in vitro but its role in vivo in the regulation of metabolism is still elusive. Hence, we sought to address the role of c-Abl in diet-induced obesity and obesity-associated insulin resistance. METHODS: The expression of c-Abl in different fat tissues from obese humans or mice fed a high-fat diet (HFD) were first analysed by western blotting and quantitative PCR. We employed conditional deletion of the c-Abl gene (also known as Abl1) in adipose tissue using Fabp4-Cre and 6-week-old mice were fed with either a chow diet (CD) or an HFD. Age-matched wild-type mice were treated with the c-Abl inhibitor nilotinib or with vehicle and exposed to either CD or HFD, followed by analysis of body mass, fat mass, glucose and insulin tolerance. Histological staining, ELISA and biochemical analysis were used to clarify details of changes in physiology and molecular signalling. RESULTS: c-Abl was highly expressed in subcutaneous fat from obese humans and HFD-induced obese mice. Conditional knockout of c-Abl in adipose tissue improved insulin sensitivity and mitigated HFD-induced body mass gain, hyperglycaemia and hyperinsulinaemia. Consistently, treatment with nilotinib significantly reduced fat mass and improved insulin sensitivity in HFD-fed mice. Further biochemical analyses suggested that c-Abl inhibition improved whole-body insulin sensitivity by reducing HFD-triggered insulin resistance and increasing adiponectin in subcutaneous fat. CONCLUSIONS/INTERPRETATION: Our findings define a new biological role for c-Abl in the regulation of diet-induced obesity through improving insulin sensitivity of subcutaneous fat. This suggests it may become a novel therapeutic target in the treatment of metabolic disorders.


Assuntos
Tecido Adiposo/metabolismo , Obesidade/metabolismo , Proteínas Proto-Oncogênicas c-abl/metabolismo , Gordura Subcutânea/metabolismo , Tecido Adiposo/efeitos dos fármacos , Animais , Dieta Hiperlipídica/efeitos adversos , Ingestão de Energia/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Teste de Tolerância a Glucose , Resistência à Insulina/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Obesidade/tratamento farmacológico , Obesidade/etiologia , Proteínas Proto-Oncogênicas c-abl/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-abl/deficiência , Proteínas Proto-Oncogênicas c-abl/genética , Pirimidinas/uso terapêutico , Gordura Subcutânea/efeitos dos fármacos
17.
Biol Reprod ; 90(3): 52, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24451987

RESUMO

Among nearly 100 mammalian species, implantation can be suspended at blastocyst stage for a certain time and reactivated under favorable conditions, a phenomenon known as embryonic diapause. Until now, the underlying molecular mechanism governing embryonic diapause and reactivation for implantation remained largely unknown. Here we conducted the first integral proteomic analysis of blastocysts from diapause to reactivation by using a physiologically relevant mouse delayed implantation model. More than 6000 dormant and reactivated blastocysts were used for the proteomic analysis. A total of 2255 proteins were detected. Various cellular and molecular processes, including protein translation, aerobic glycolysis, pentose phosphate pathway, purine nucleotide biosynthesis, glutathione metabolism, and chromatin organization were identified as differentially regulated. In particular, we demonstrated a remarkable activation of mitochondria in blastocysts upon reactivation from dormancy, highlighting their essential physiological significance. Moreover, the activities of the endosome-lysosome system were prominently enhanced in the mural trophectoderm of reactivated blastocysts, accompanied by active phagocytosis at the fetal-maternal interface, suggesting a critical role in promoting trophoblast invasion. Collectively, we provided an integral proteomic view upon the regulatory network of blastocyst reactivation from diapause, which will help to better interpret the nature of embryonic diapause and reactivation in wild animals and to identify molecular indicators for selecting blastocysts with high implantation competency.


Assuntos
Blastocisto/metabolismo , Blastocisto/fisiologia , Implantação do Embrião/genética , Implantação do Embrião/fisiologia , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Blastocisto/química , Western Blotting , Cromatografia Líquida de Alta Pressão , Corantes , Endossomos/fisiologia , Metabolismo Energético/fisiologia , Feminino , Imunofluorescência , Glutationa/metabolismo , Leucina/metabolismo , Lisossomos/fisiologia , Masculino , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Via de Pentose Fosfato/fisiologia , Gravidez , Nucleotídeos de Purina/biossíntese , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas em Tandem
18.
Cell Metab ; 36(3): 459-460, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38447527

RESUMO

It is generally believed that the contributions of the UCP1-independent thermogenic pathways are secondary to UCP1-mediated thermogenesis in BAT. Now, Rahbani et al. demonstrate in vivo that adaptive thermogenesis in brown adipose tissue is regulated by UCP1 and CKB in parallel.


Assuntos
Tecido Adiposo Marrom , Termogênese
19.
Food Funct ; 15(2): 967-976, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38175708

RESUMO

Increasing evidence suggests that brown adipose tissue (BAT) plays an important role in obesity and related diseases. Increasing the amount or activity of BAT could prevent obesity. Therefore, a safe and effective method of activating BAT is urgently required. Here, we evaluated the potential effects of lotus leaf extract (LLE) on BAT function. We found that LLE substantially increased UCP1 mRNA and protein levels as well as thermogenic protein expression in primary brown adipocytes. Additionally, LLE treatment reduced diet-induced obesity and improved glucose homeostasis owing to BAT activation and increased energy expenditure. We found that nuciferine, an active ingredient of LLE, could dose-dependently activate BAT in vitro and in vivo, alleviate diet-induced obesity, and improve glucose homeostasis by increasing energy expenditure. Mechanistically, we found that nuciferine induced PPARG coactivator 1 alpha (PGC1-α) expression, which is a key gene involved in mitochondrial biogenesis promoter activity, by directly binding to RXRA. Furthermore, RXRA knockdown abolished expression of the nuciferine-induced mitochondrial and thermogenesis-related gene in primary brown adipocytes. In summary, we found that LLE and nuciferine have a notable effect on BAT activation and highlight the potential applications of the main component of LLE in preventing obesity and treating metabolic disorders.


Assuntos
Tecido Adiposo Marrom , Aporfinas , Humanos , Tecido Adiposo Marrom/metabolismo , Obesidade/genética , Obesidade/prevenção & controle , Obesidade/metabolismo , Aporfinas/farmacologia , Metabolismo Energético , Glucose/metabolismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-37743432

RESUMO

Novel antibiotic substitutes are increasingly in demand in the animal husbandry industry. An oral recombinant Lactococcus lactis (L. lactis) expressing human LL-37 (oral LL-37) was developed and its safety and antiviral effectiveness in vivo was tested. In addition to impairing liposome integrity, LL-37 polypeptide from recombinant L. lactis could prevent the host cell infection by a variety of viruses, including recombinant SARS, SARS-CoV-2, Ebola virus, and vesicular stomatitis virus G. Subchronic toxicity studies performed on Sprague-Dawley rats showed that no cumulative toxicity was found during short-term intervention. Oral LL-37 treatment after the onset of fever could reduce mortality in piglets infected with porcine reproductive and respiratory syndrome virus. Moreover, body weight gain of piglets receiving treatment was progressively restored, and nucleic acid positive rebound was not undetected after discontinuation. Oral LL-37 consistently increased the lifespan of chickens infected with Newcastle viruses. These findings suggested a potential use of recombinantly modified microorganisms in veterinary medicine.

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