RESUMO
The prevalence of obesity is increasing globally and is associated with many metabolic disorders, such as type 2 diabetes and cardiovascular diseases. In recent years, a number of studies suggest that promotion of white adipose browning represents a promising strategy to combat obesity and its related metabolic disorders. The aim of this study was to identify compounds that induce adipocyte browning and elucidate their mechanism of action. Among the 500 natural compounds screened, a small molecule named Rutaecarpine, was identified as a positive regulator of adipocyte browning both in vitro and in vivo. KEGG pathway analysis from RNA-seq data suggested that the AMPK signaling pathway was regulated by Rutaecarpine, which was validated by Western blot analysis. Furthermore, inhibition of AMPK signaling mitigated the browning effect of Rutaecaripine. The effect of Rutaecaripine on adipocyte browning was also abolished upon deletion of Prdm16, a downstream target of AMPK pathway. In collusion, Rutaecarpine is a potent chemical agent to induce adipocyte browning and may serve as a potential drug candidate to treat obesity.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos Bege/efeitos dos fármacos , Adipócitos Bege/metabolismo , Adipócitos Brancos/efeitos dos fármacos , Adipócitos Brancos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Alcaloides Indólicos/farmacologia , Quinazolinas/farmacologia , Fatores de Transcrição/metabolismo , Adipócitos Bege/citologia , Adipócitos Brancos/citologia , Animais , Produtos Biológicos/farmacologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Transgênicos , Modelos Biológicos , Obesidade/tratamento farmacológico , Obesidade/genética , Obesidade/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Termogênese/efeitos dos fármacos , Termogênese/genética , Termogênese/fisiologiaRESUMO
BACKGROUND: Previous studies have demonstrated that serum amyloid A (SAA) levels are correlated with the clinical outcomes of solid tumors. However, the available data have not been systematically evaluated. The objective of the present meta-analysis was to explore the prognostic value of SAA levels in solid tumors. METHODS: Eligible studies were identified from the PubMed, EMBASE and Science Citation Index electronic databases. The clinical characteristics, disease/progression-free survival (DFS/PFS) and overall survival (OS) were extracted from the eligible studies. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated with Stata 12.0 software. We also performed subgroup, meta-regression and sensitivity analyses. RESULTS: In total, 12 eligible studies including 2749 patients were enrolled in the present meta-analysis. The pooled HRs with 95% CIs showed that elevated levels of SAA were significantly associated with poor OS (HR = 3.01, 95% CI 1.96-4.63) and DFS/PFS (HR = 1.67, 95% CI 1.31-2.12) in patients with solid tumors. Although publication bias was seem found in the studies with regard to OS, a further trim and fill analysis revealed that the adjusted HR was 3.02 (95% CI 1.96-4.63), which was close to the original HR. Subgroup analysis confirmed an elevated level of SAA as a strong prognostic marker in patients with solid tumors, regardless of tumor type, detection method, cut-off value, sample size, area and variance analyses. CONCLUSION: Our meta-analysis indicated that elevated levels of SAA might be an unfavorable prognostic marker for OS in patients with solid tumors.
RESUMO
BACKGROUND: Altered composition of the gut microbiota is involved in both the onset and progression of obesity and diabetes mellitus. However, the link between gut microbiota and obesity-related cardiovascular complications has not been explored. The present study was designed to investigate the role of Akkermansia muciniphila, a mucin-degrading bacterium with beneficial effects on metabolism, in the pathogenesis of atherosclerosis in apolipoprotein E-deficient (Apoe(-/-)) mice. METHODS AND RESULTS: Apoe(-/-) mice on normal chow diet or a Western diet were treated with A muciniphila by daily oral gavage for 8 weeks, followed by histological evaluations of atherosclerotic lesion in aorta. Real-time polymerase chain reaction analysis demonstrated that the fecal abundance of A muciniphila was significantly reduced by Western diet. Replenishment with A muciniphila reversed Western diet-induced exacerbation of atherosclerotic lesion formation without affecting hypercholesterolemia. A muciniphila prevented Western diet-induced inflammation in both the circulation and local atherosclerotic lesion, as evidenced by reduced macrophage infiltration and expression of proinflammatory cytokines and chemokines. These changes were accompanied by a marked attenuation in metabolic endotoxemia. A muciniphila-mediated reduction in circulating endotoxin level could be attributed to the induction of intestinal expression of the tight junction proteins (zona occuldens protein-1 and occludin), thereby reversing Western diet-induced increases in gut permeability. Long-term infusion of endotoxin to Apoe(-/-) mice reversed the protective effect of A muciniphila against atherosclerosis. CONCLUSION: A muciniphila attenuates atherosclerotic lesions by ameliorating metabolic endotoxemia-induced inflammation through restoration of the gut barrier.
Assuntos
Aterosclerose/prevenção & controle , Endotoxemia/prevenção & controle , Inflamação/prevenção & controle , Intestinos/microbiologia , Verrucomicrobia/fisiologia , Animais , Aterosclerose/microbiologia , Aterosclerose/patologia , Células CACO-2 , Modelos Animais de Doenças , Endotoxemia/etiologia , Endotoxemia/microbiologia , Humanos , Inflamação/etiologia , Inflamação/microbiologia , Masculino , Camundongos , Camundongos Transgênicos , Resultado do TratamentoRESUMO
Emerging evidence indicates that ß-galactoside-α2,3-sialyltransferase III (ST3Gal3) involves in development, inflammation, neoplastic transformation, and metastasis. However, the role of ST3Gal3 in regulating cancer chemoresistance remains elusive. Herein, we investigated the functional effects of ST3Gal3 in cisplatin-resistant ovarian cancer cells. We found that the levels of ST3Gal3 mRNA differed significantly among ovarian cancer cell lines. HO8910PM cells that have high invasive and metastatic capacity express elevated ST3Gal3 mRNA and are resistant to cisplatin, comparing to SKOV3 cells that have a lower level of ST3Gal3 expression and are more chemosensitive to cisplatin. We found that the expression of ST3Gal3 has reverse correlation with the dosage of cisplatin used in both SKOV3 and HO8910PM cells, and high dose of cisplatin could down-regulate ST3Gal3 expression. We then examined the functional effects of ST3Gal3 knockdown in cancer cell lines using FACS analysis. The number of apoptotic cells was much higher in cells if ST3Gal3 expression was knocked down by siRNA and/or by treating cells with higher dosage of cisplatin in comparison to control cells. Interestingly, in HO8910PM cells with ST3Gal3 knockdown, the levels of caspase 8 and caspase 3 proteins increased, which was more obvious in cells treated with both ST3Gal3 knockdown and cisplatin, suggesting that ST3Gal3 knockdown synergistically enhanced cisplatin-induced apoptosis in ovarian cancer cells. Taken together, these results uncover an alternative mechanism of cisplatin-resistance through ST3Gal3 and open a window for effective prevention of chemoresistance and relapse of ovarian cancer by targeting ST3Gal3.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cisplatino/farmacologia , Neoplasias Ovarianas/metabolismo , Sialiltransferases/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Feminino , Técnicas de Silenciamento de Genes , Humanos , Recidiva Local de Neoplasia , RNA Interferente Pequeno/metabolismo , Sialiltransferases/metabolismo , beta-Galactosídeo alfa-2,3-SialiltransferaseRESUMO
BACKGROUND & AIMS: Inflammatory cell infiltration in the liver is a hallmark of non-alcoholic steatohepatitis (NASH). However, the pathological events which trigger the infiltration of inflammatory cells to mediate NASH pathogenesis remains poorly understood. This study aims to investigate the role of neutrophil-derived lipocalin 2 (LCN2) in mediating the transition from simple steatosis to NASH. METHODS: Animal models of NASH were induced by high fat high cholesterol (HFHC) diet and methionine- and choline-deficient (MCD) diet in LCN2 knockout mice and wild-type controls. RESULTS: Circulating levels of LCN2 and its hepatic expression were markedly increased in both murine models and human subjects with NASH, and these changes were associated with increased infiltration of neutrophils. In diet-induced NASH models, hepatic injury, necroinflammation and infiltration of neutrophils and macrophages were substantially attenuated by genetic depletion of LCN2. In contrast, chronic infusion of recombinant LCN2 exacerbated diet-induced liver injury, inflammation and macrophage accumulation in a neutrophil-dependent manner. Primary mouse neutrophils lacking LCN2 exhibited a defective migration capacity, which can be reversed by replenishment with recombinant LCN2. Mechanistically, LCN2 induced the expression of the chemokine (C-X-C motif) receptor 2 (CXCR2), thereby leading to activation of ERK1/2 and production of proinflammatory chemokines. LCN2-induced inflammation, infiltration of macrophages and liver injury was abrogated in CXCR2-deficient mice. CONCLUSIONS: These findings demonstrated that LCN2 acts as a central mediator to facilitate the crosstalk between neutrophils and hepatic macrophages via induction of the chemokine receptor CXCR2, thereby exacerbating steatohepatitis. LAY SUMMARY: Lipocalin-2 levels in blood and the liver were markedly increased in both mouse models and human subjects with NASH, and these changes were associated with increased infiltration of neutrophils in the liver. In diet-induced NASH models, hepatic injury, necroinflammation and infiltration of neutrophils and macrophages were substantially attenuated by genetic depletion of lipocalin-2, but was augmented by chronic infusion of recombinant lipocalin-2. Lipocalin-2 induced the expression of the chemokine receptor CXCR2, thereby leading to activation of the mitogen-activated protein (MAP) kinase ERK1/2 and production of proinflammatory chemokines. Lipocalin-2-induced inflammation, infiltration of macrophages and liver injury was abrogated in CXCR2-deficient mice.
Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Modelos Animais de Doenças , Humanos , Lipocalina-2 , Fígado , Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos , Receptores de Interleucina-8BRESUMO
BACKGROUND & AIMS: Acetaminophen (APAP) overdose causes hepatic necrosis and acute liver injury by inducing mitochondrial dysfunction and damage. Although the biochemical pathways that mediate APAP-induced hepatotoxicity have been well studied, the body's defense mechanism to attenuate this disease remains elusive. This study investigated the roles of adiponectin, an adipocyte-secreted adipokine with pleiotropic protective effects against obesity-related metabolic dysfunction, in the pathogenesis of APAP-induced liver injury in mice. METHODS: Adiponectin knockout (ADN KO) and C57 wild type mice were treated with an overdose of APAP, followed by histological and biochemical evaluation of liver injury and activation of autophagy. The mechanism of adiponectin in APAP-induced hepatocytic toxicity was also explored in primary cultured hepatocytes. RESULTS: APAP overdose triggers a marked accumulation of adiponectin in injured liver tissues. ADN KO mice exhibit severely exacerbated mitochondrial dysfunction and damage, oxidative stress and necrosis and much higher mortality in response to APAP overdose, whereas these changes are reversed by a single injection of adiponectin. Mechanistically, adiponectin induces autophagosome formation by AMP-activated protein kinase (AMPK)-dependent activation of the Unc-51-like kinase 1, consequently leading to the removal of damaged mitochondria from hepatocytes. The protective effects of adiponectin against APAP-induced mitochondrial damage, oxidative stress and necrosis are abrogated by blockage of AMPK or pharmacological inhibition of autophagy. CONCLUSIONS: Our findings suggest that the APAP-induced accumulation of adiponectin in liver tissues serves as an adaptive mechanism to ameliorate hepatotoxicity by promoting autophagy-mediated clearance of damaged mitochondria. Adiponectin agonists may represent a promising therapy for the drug-induced acute liver failure.
Assuntos
Acetaminofen/toxicidade , Adiponectina/metabolismo , Doença Hepática Induzida por Substâncias e Drogas , Fígado/patologia , Mitocôndrias Hepáticas/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Analgésicos não Narcóticos/toxicidade , Animais , Autofagia/fisiologia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Citoproteção , Overdose de Drogas/metabolismo , Hepatócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Serina-Treonina Quinases/metabolismoRESUMO
PURPOSE: Methyltransferase-like 3 (METTL3), a key member of the m6A methyltransferase complex, is upregulated in multiple human malignancies and plays a role in regulating tumor migration. This study aimed to reveal the underlying mechanism by which METTL3 in regulates the metastasis of colorectal cancer (CRC). METHODS: We compared METTL3 expression levels in CRC tumor tissues and adjacent nontumor tissues by immunohistochemistry (IHC). The functional roles of METTL3 in CRC were assessed by real-time cell migration assays, wound-healing assays and Transwell assays. miRNA sequencing (miRNA-seq), RNA-binding protein immunoprecipitation (RIP) assays and N6-methyladenosine immunoprecipitation (MeRIP) assays were performed to confirm the molecular mechanism underlying the involvement of METTL3 in CRC cell metastasis. RESULTS: We found that METTL3 was overexpressed in CRC tissues. METTL3 knockdown significantly inhibited CRC cell migration and invasion, while METTL3 overexpression had the opposite effects. Furthermore, we demonstrated that METTL3 regulates miR-196b expression via an N6-methyladenosine (m6A)-pri-miR-196b-dependent mechanism and thereby promotes CRC metastasis. CONCLUSION: This study shows the important role of METTL3 in CRC metastasis and provides novel insight into m6A modification in CRC metastasis.
Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , MicroRNAs/genética , Adenosina , Movimento Celular/genética , Metiltransferases/genética , Neoplasias Colorretais/genéticaRESUMO
OBJECTIVE: To explore whether casticin (CAS) suppresses stemness in cancer stem-like cells (CSLCs) obtained from human cervical cancer (CCSLCs) and the underlying mechanism. METHODS: Spheres from HeLa and CaSki cells were used as CCSLCs. DNA methyltransferase 1 (DNMT1) activity and mRNA levels, self-renewal capability (Nanog and Sox2), and cancer stem cell markers (CD133 and CD44), were detected by a colorimetric DNMT activity/inhibition assay kit, quantitative real-time reverse transcription-polymerase chain reaction, sphere and colony formation assays, and immunoblot, respectively. Knockdown and overexpression of DNMT1 by transfection with shRNA and cDNA, respectively, were performed to explore the mechanism for action of CAS (0, 10, 30, and 100 nmol/L). RESULTS: DNMT1 activity was increased in CCSLCs compared with HeLa and CaSki cells (P<0.05). In addition, HeLa-derived CCSLCs transfected with DNMT1 shRNA showed reduced sphere and colony formation abilities, and lower CD133, CD44, Nanog and Sox2 protein expressions (P<0.05). Conversely, overexpression of DNMT1 in HeLa cells exhibited the oppositive effects. Furthermore, CAS significantly reduced DNMT1 activity and transcription levels as well as stemness in HeLa-derived CCSLCs (P<0.05). Interestingly, DNMT1 knockdown enhanced the inhibitory effect of CAS on stemness. As expected, DNMT1 overexpression reversed the inhibitory effect of CAS on stemness in HeLa cells. CONCLUSION: CAS effectively inhibits stemness in CCSLCs through suppression of DNMT1 activation, suggesting that CAS acts as a promising preventive and therapeutic candidate in cervical cancer.
Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Linhagem Celular Tumoral , Células HeLa , Células-Tronco Neoplásicas/metabolismo , RNA Interferente Pequeno/metabolismo , Neoplasias do Colo do Útero/metabolismoRESUMO
Ovarian cancer (OC) is the most lethal of all gynecologic malignancies with poor survival rates. Although surgical treatment and chemotherapy had advanced to improve survival, platinum-based chemoresistance remains a major hurdle in the clinical treatment of OC. The search for novel active ingredients for the treatment of drug-resistant OC is urgently needed. Here, we demonstrated that icaritin, the main active ingredient derived from the traditional Chinese herb Epimedium genus, significantly suppressed the proliferation, migration, and invasion of both drug-susceptible and cisplatin-resistant OC cells in vitro. Mechanistically, icaritin at 20 µM significantly inhibited the phosphorylation of Akt and mTOR, as well as decreased the expression of vimentin and increased the expression of E-cadherin. Our data indicate that icaritin, a prenylated flavonoid natural product, could serve as a potential inhibitor of cisplatin-resistant OC by inhibiting the Akt/mTOR signaling pathway.
RESUMO
BACKGROUND: C-X-C chemokine ligand 16 (CXCL16) is a scavenger receptor for oxidized low-density lipoprotein that has been shown to promote atherogenic effects in vivo and to predict the long-term mortality in acute coronary syndrome. We conducted a cross-sectional study to test the hypothesis that elevated CXCL16 concentrations are associated with the change in renal function in patients with chronic kidney disease (CKD) at different stages of disease. MATERIALS AND METHODS: Two hundred and forty subjects including 200 patients with CKD (146 CKD from outpatients and 54 CKD with long-term haemodialysis) and 40 normal control subjects were recruited into this study. All CKD subjects underwent echocardiograms to assess left ventricular mass index. Plasma levels of CXCL16 and other relevant clinical and biochemical parameters in all subjects were obtained upon standard clinical examinations. RESULTS: Plasma CXCL16 levels were significantly increased with the development of CKD from early- and end-stage (P < 0·001 for trend) and significantly higher in CKD subjects than those of normal subjects (P<0·001). Furthermore, plasma CXCL16 levels in CKD patients with type 2 diabetes mellitus (DM) were higher than those of CKD patients without DM. Multiple stepwise regression analyses indicated that plasma CXCL16 levels were independently associated with estimated glomerular filtration rate, C-reactive protein and adiponectin (all P<0·05). CONCLUSIONS: Plasma CXCL16 levels are significantly increased with the development of early- to end-stage CKD and are independently associated with the change in renal function. Elucidating the role of CXCL16 as a biomarker or disease modifier in CKD progression requires further study.
Assuntos
Quimiocina CXCL6/sangue , Diabetes Mellitus Tipo 2/sangue , Falência Renal Crônica/sangue , Adulto , Idoso , Biomarcadores/metabolismo , Estudos de Casos e Controles , Estudos Transversais , Ecocardiografia , Feminino , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Receptores Depuradores/metabolismo , Análise de Regressão , Diálise RenalRESUMO
There are significant gender differences in the incidence and mortality of hepatocellular carcinoma (HCC). Compared with men, the incidence and mortality of HCC in women are relatively low. The estrogen signaling pathway, composed of estrogen and estrogen receptors, has been postulated to have a protective effect on the occurrence and development of HCC. There have been multiple studies that have supported anti-HCC effects of the estrogen signaling pathways, including direct and indirect pathways such as genomic pathways, rapid transduction pathways, non-coding RNA, tumor microenvironment, estrogen metabolites, and inhibition of hepatitis infection and replication. Based on the evidence of an anti-HCC effect of the estrogen signaling pathway, a number of strategies have been investigated to determine the potential therapeutic effect. These have included estrogen replacement therapy, targeting the estrogen receptor, key molecules, inflammatory mediators, and regulatory pathways of the estrogen signaling pathway. In this review, we have systematically summarized the latest developments in the complex functions and molecular mechanisms of the estrogen signaling pathway in liver cancer. Furthermore, we have highlighted the potential targets of treatment strategies based on the estrogen signaling pathway in the treatment of liver cancer and the principal obstacles currently encountered for future investigation.
RESUMO
Recent studies have identified pleiotropic roles of methyltransferase-like 3 (METTL3) in tumor progression. However, the roles of METTL3 in esophageal squamous cell carcinoma (ESCC) are still unclear. Here, we investigated the function and mechanism of METTL3 in ESCC tumorigenesis. We reported that higher METTL3 expression was found in ESCC tissues and was markedly associated with depth of invasion and poor prognosis. Loss- and gain-of function studies showed that METTL3 promoted the migration and invasion of ESCC cells in vitro. Integrated methylated RNA immunoprecipitation sequencing (MeRIP-Seq) and RNA sequencing (RNA-Seq) analysis first demonstrated that glutaminase 2 (GLS2) was regulated by METTL3 via m6A modification. Our findings identified METTL3/GLS2 signaling as a potential therapeutic target in antimetastatic strategies against ESCC.
RESUMO
PURPOSE: EF24, a synthetic analogue of curcumin, was developed as an anti-tumor compound to induce apoptosis, inhibit proliferation and metastasis in various cancers. However, whether EF24 induces ferroptosis in osteosarcoma cells or not, and its underlying mechanism remains largely elusive. METHODS: After EF24 combining with or without other compounds treatments, mRNA expression profiles were proceeded by RNA sequencing. Cytotoxicity was measured by cell counting kit-8 assay. Cell death was quantified by flow cytometer. Gene expression was quantified by real-time PCR. Protein level was detected by western blot. Malonydialdehyde (MDA) level was measured by lipid peroxidation MDA assay kit. Reactive oxygen species (ROS) level was measured by ROS Assay Kit. Ferric ion was measured by Iron Assay kit. RESULTS: EF24 significantly induced cell death in osteosarcoma cell lines, and this effect was significantly reversed by ferrostatin-1, but not Z-VAD(Ome)-FMK, MRT68921 or necrosulfonamide. EF24 significantly increased MDA level, ROS level and intracellular ferric ion level, these effects were significantly attenuated by ferrostatin-1. EF24 upregulated HMOX1 expression in a dose dependent manner, overexpression of HMOX1 facilitated EF24 to induce ferroptosis in osteosarcoma cell lines. HMOX1 knockdown attenuated EF24-induced cytotoxicity and attenuated EF24-induced inhibition of Glutathione Peroxidase 4 (GPX4) expression. CONCLUSION: Our results showed that EF24 upregulated HMOX1 to suppress GPX4 expression to induce ferroptosis by increasing MDA level, ROS level and intracellular ferric ion level. Thus, EF24 might serve as a potential agent for the treatment of HMOX1-positive osteosarcoma patients.
Assuntos
Antineoplásicos/farmacologia , Compostos de Benzilideno/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Ferroptose/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Osteossarcoma/tratamento farmacológico , Piperidonas/farmacologia , Neoplasias Ósseas/enzimologia , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Heme Oxigenase-1/genética , Humanos , Ferro/metabolismo , Malondialdeído/metabolismo , Osteossarcoma/enzimologia , Osteossarcoma/genética , Osteossarcoma/patologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de SinaisRESUMO
BACKGROUND & AIMS: Hepatosteatosis, defined as excessive intrahepatic lipid accumulation, represents the first step of NAFLD. When combined with additional cellular stress, this benign status progresses to local and systemic pathological conditions such as NASH and insulin resistance. However, the molecular events directly caused by hepatic lipid build-up, in terms of its impact on liver biology and peripheral organs, remain unclear. Carnitine palmitoyltransferase 1A (CPT1A) is the rate limiting enzyme for long chain fatty acid beta-oxidation in the liver. Here we utilise hepatocyte-specific Cpt1a knockout (LKO) mice to investigate the physiological consequences of abolishing hepatic long chain fatty acid metabolism. APPROACH & RESULTS: Compared to the wild-type (WT) littermates, high fat diet (HFD)-fed LKO mice displayed more severe hepatosteatosis but were otherwise protected against diet-induced weight gain, insulin resistance, hepatic ER stress, inflammation and damage. Interestingly, increased energy expenditure was observed in LKO mice, accompanied by enhanced adipose tissue browning. RNAseq analysis revealed that the peroxisome proliferator activator alpha (PPARα)- fibroblast growth factor 21 (FGF21) axis was activated in liver of LKO mice. Importantly, antibody-mediated neutralization of FGF21 abolished the healthier metabolic phenotype and adipose browning in LKO mice, indicating that the elevation of FGF21 contributes to the improved liver pathology and adipose browning in HFD-treated LKO mice. CONCLUSIONS: Liver with deficient CPT1A expression adopts a healthy steatotic status that protects against HFD-evoked liver damage and potentiates adipose browning in an FGF21-dependent manner. Inhibition of hepatic CPT1A may serve as a viable strategy for the treatment of obesity and NAFLD.
RESUMO
BACKGROUND & AIMS: Hepatosteatosis, defined as excessive intrahepatic lipid accumulation, represents the first step of NAFLD. When combined with additional cellular stress, this benign status progresses to local and systemic pathological conditions such as NASH and insulin resistance. However, the molecular events directly caused by hepatic lipid build-up, in terms of its impact on liver biology and peripheral organs, remain unclear. Carnitine palmitoyltransferase 1A (CPT1A) is the rate limiting enzyme for long chain fatty acid beta-oxidation in the liver. Here we utilise hepatocyte-specific Cpt1a knockout (LKO) mice to investigate the physiological consequences of abolishing hepatic long chain fatty acid metabolism. APPROACH & RESULTS: Compared to the wild-type (WT) littermates, high fat diet (HFD)-fed LKO mice displayed more severe hepatosteatosis but were otherwise protected against diet-induced weight gain, insulin resistance, hepatic ER stress, inflammation and damage. Interestingly, increased energy expenditure was observed in LKO mice, accompanied by enhanced adipose tissue browning. RNAseq analysis revealed that the peroxisome proliferator activator alpha (PPARα)- fibroblast growth factor 21 (FGF21) axis was activated in liver of LKO mice. Importantly, antibody-mediated neutralization of FGF21 abolished the healthier metabolic phenotype and adipose browning in LKO mice, indicating that the elevation of FGF21 contributes to the improved liver pathology and adipose browning in HFD-treated LKO mice. CONCLUSIONS: Liver with deficient CPT1A expression adopts a healthy steatotic status that protects against HFD-evoked liver damage and potentiates adipose browning in an FGF21-dependent manner. Inhibition of hepatic CPT1A may serve as a viable strategy for the treatment of obesity and NAFLD.
RESUMO
BACKGROUND: Gamma-delta (γδ) T lymphocytes are primed to potently respond to pathogens and transformed cells by recognizing a broad range of antigens. However, adoptive immunotherapy with γδT cells has exhibited mixed treatment responses. Better understanding of γδT cell biology and stratifying healthy donors for allogeneic adoptive therapy is clinically needed to fully realize the therapeutic potential of γδT cells. METHODS: We examine 98 blood samples from healthy donors and measure their expansion capacity after zoledronate stimulation, and test the migration and cytotoxic effector function of expanded γδT cells in 2D culture, 3D tumor spheroid and patient-derived melanoma organoid assays. RESULTS: We find that γδT cell expansion capacity is independent of expansion methods, gender, age and HLA type. Basal γδT cell levels in Peripheral blood mononuclear cell (PBMC) correlate well with their expansion, migration and cytotoxic effector capacity in vitro. Circulating γδT cells with lower expression of PD-1, CTLA-4, Eomes, T-bet and CD69, or higher IFN-γ production expand better. γδT cells with central memory and effector memory phenotypes are significantly more abundant in good expanders. A cut-off level of 0.82% γδT cells in PBMC stratifies good versus poor γδT cell expansion with a sensitivity of 97.78%, specificity of 90.48% and area under the curve of 0.968 in a healthy individual. Donors with higher Vδ2 Index Score in PBMC have greater anti-tumor functions including migratory function and cytotoxicity. CONCLUSIONS: Our results demonstrate that the interindividual γδT cell functions correlate with their circulating levels in healthy donors. Examination of circulating γδT cell level may be used to select healthy donors to participate in γδT-based immunotherapies.
Assuntos
Proliferação de Células , Linfócitos Intraepiteliais/imunologia , Ativação Linfocitária , Adulto , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Técnicas de Cocultura , Citotoxicidade Imunológica , Feminino , Voluntários Saudáveis , Humanos , Memória Imunológica , Imunofenotipagem , Linfócitos Intraepiteliais/efeitos dos fármacos , Linfócitos Intraepiteliais/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Contagem de Linfócitos , Masculino , Melanoma/imunologia , Melanoma/metabolismo , Melanoma/patologia , Pessoa de Meia-Idade , Fenótipo , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Adulto Jovem , Ácido Zoledrônico/farmacologiaRESUMO
The development of non-invasive ocular drug delivery systems is of practical importance in the treatment of retinal disease. In this study, we evaluated the efficacy of transactivator of transcription protein transduction domain (TAT-PTD, TAT(49-57)) as a vehicle to deliver acidic FGF (aFGF) to retina in rats. TAT-conjugated aFGF-His (TAT-aFGF-His) exhibited efficient penetration into the retina following topical administration to the ocular surface. Immunochemical staining with anti-His revealed that TAT-aFGF-His proteins were readily found in the retina (mainly in the ganglion cell layer) at 30 min. and remained detectable for at least 8 hrs after administration. In contrast, His(+) proteins were undetectable in the retina after topical administration of aFGF-His, indicating that aFGF-His cannot penetrate the ocular barrier. Furthermore, TAT-aFGF-His, but not aFGF-His, mediated significant protection against retinal ischemia-reperfusion (IR) injury. After IR injury, retina from TAT-aFGF-His-treated rats showed better-maintained inner retinal layer structure, reduced apoptosis of retinal ganglion cells and improved retinal function compared to those treated with aFGF-His or PBS. These results indicate that conjugation of TAT to aFGF-His can markedly improve the ability of aFGF-His to penetrate the ocular barrier without impairing its biological function. Thus, TAT(49-57) provides a potential vehicle for efficient drug delivery in the treatment of retinal disease.
Assuntos
Fatores de Crescimento de Fibroblastos/administração & dosagem , Produtos do Gene tat/administração & dosagem , Traumatismo por Reperfusão/prevenção & controle , Retina/metabolismo , Animais , RatosRESUMO
Colon cancer is a leading cause of morbidity and mortality in Western countries. Basic fibroblast growth factor (bFGF) was up-regulated in patients with colon cancer and was considered as a potential therapeutic target. In this study, we first demonstrated that a novel bFGF-binding peptide (named P7) inhibited proliferation of several colon cancer cell lines including HT-29, LoVo, and Caco2 cells stimulated by bFGF. Further investigations with HT-29 cells indicated that P7 arrested the cell cycle at the G0/G1 phase of bFGF-stimulated cells, reduced the levels of phospho-Erk1/Erk2 induced by bFGF, and caused significant changes in the expression of proteins related to proliferation, cell cycle, and cancer. Our results suggested that the bFGF-binding peptide has a potential antitumor effect on colon cancer.
Assuntos
Antineoplásicos/farmacologia , Proteínas de Transporte/farmacologia , Neoplasias do Colo/tratamento farmacológico , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Ciclo Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Fator 2 de Crescimento de Fibroblastos/metabolismo , Células HT29 , Humanos , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Diabetes impairs the expression and function of endogenous growth factors, leading to increased cardiovascular events in diabetic patients. Supplementation of fibroblast growth factors (FGFs) protected the heart from ischemia/reperfusion (I/R)-induced injury in animal models. However, it has not yet been tested in diabetic heart. The present study was thus to clarify whether basic fibroblast growth factor (bFGF) could protect the heart from I/R-induced damage under diabetic conditions using a rat model. Male Sprague Dawley rats were used to induce diabetes by intraperitoneal injection of streptozotocin. Eight weeks later, I/R injury was generated in diabetic rats and age-matched non-diabetic rats. All I/R rats were administrated bFGF or saline through intramyocardial injection. Seven days after I/R, cardiac infarction, structural changes, cell death and blood vessel density, serum malondialdehyde (MDA) and cardiac enzyme lactate dehydrogenase (LDH) were examined. We found that I/R induced significant increases in the cardiac infarction, blood MDA contents and LDH activities, and the expression of caspase-3. Treatment of I/R rats with bFGF simultaneously with reperfusion significantly attenuated I/R-induced pathological changes, along with a significant increase in the cardiac blood vessel density in both diabetic and non-diabetic rates. The protective effects of bFGF on I/R-induced cardiac injury in diabetic group are less than those in non-diabetic group. The results indicated that bFGF provide a protection of the heart against I/R-induced oxidative damage, cell death and infarction under diabetic conditions.