RESUMO
High-risk neuroblastoma (NB) is a significant clinical challenge. MYCN and Anaplastic Lymphoma Kinase (ALK), which are often involved in high-risk NB, lead to increased replication stress in cancer cells, suggesting therapeutic strategies. We previously identified an ATR (ataxia telangiectasia and Rad3-related)/ALK inhibitor (ATRi/ALKi) combination as such a strategy in two independent genetically modified mouse NB models. Here, we identify an underlying molecular mechanism, in which ALK signaling leads to phosphorylation of ATR and CHK1, supporting an effective DNA damage response. The importance of ALK inhibition is supported by mouse data, in which ATRi monotreatment resulted in a robust initial response, but subsequent relapse, in contrast to a 14-d ALKi/ATRi combination treatment that resulted in a robust and sustained response. Finally, we show that the remarkable response to the 14-d combined ATR/ALK inhibition protocol reflects a robust differentiation response, reprogramming tumor cells to a neuronal/Schwann cell lineage identity. Our results identify an ability of ATR inhibition to promote NB differentiation and underscore the importance of further exploring combined ALK/ATR inhibition in NB, particularly in high-risk patient groups with oncogene-induced replication stress.
Assuntos
Neuroblastoma , Receptores Proteína Tirosina Quinases , Humanos , Camundongos , Animais , Quinase do Linfoma Anaplásico/genética , Receptores Proteína Tirosina Quinases/metabolismo , Proliferação de Células , Linhagem Celular Tumoral , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Neuroblastoma/patologia , Reparo do DNA , Dano ao DNA , Proteínas Mutadas de Ataxia Telangiectasia/genéticaRESUMO
OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD), the primary hepatic consequence of obesity, is affecting about 25% of the global adult population. The aim of this study was to examine the in vivo role of STE20-type protein kinase TAOK3, which has been previously reported to regulate hepatocellular lipotoxicity in vitro, in the development of NAFLD and systemic insulin resistance in the context of obesity. METHODS: Taok3 knockout mice and wild-type littermates were challenged with a high-fat diet. Various in vivo tests were performed to characterize the whole-body metabolism. NAFLD progression in the liver, and lipotoxic damage in adipose tissue, kidney, and skeletal muscle were compared between the genotypes by histological assessment, immunofluorescence microscopy, protein and gene expression profiling, and biochemical assays. Intracellular lipid accumulation and oxidative/ER stress were analyzed in cultured human and mouse hepatocytes where TAOK3 was knocked down by small interfering RNA. The expression of TAOK3-related STE20-type kinases was quantified in different organs from high-fat diet-fed Taok3-/- and wild-type mice. RESULTS: TAOK3 deficiency had no impact on body weight or composition, food consumption, locomotor activity, or systemic glucose or insulin homeostasis in obese mice. Consistently, Taok3-/- mice and wild-type littermates developed a similar degree of high-fat diet-induced liver steatosis, inflammation, and fibrosis, and we detected no difference in lipotoxic damage of adipose tissue, kidney, or skeletal muscle when comparing the two genotypes. In contrast, the silencing of TAOK3 in vitro markedly suppressed ectopic lipid accumulation and metabolic stress in mouse and human hepatocytes. Interestingly, the hepatic mRNA abundance of several TAOK3-related kinases, which have been previously implicated to increase the risk of NAFLD susceptibility, was significantly elevated in Taok3-/- vs. wild-type mice. CONCLUSIONS: In contrast to the in vitro observations, genetic deficiency of TAOK3 in mice failed to mitigate the detrimental metabolic consequences of chronic exposure to dietary lipids, which may be partly attributable to the activation of liver-specific compensation response for the genetic loss of TAOK3 by related STE20-type kinases.
Assuntos
Hepatopatia Gordurosa não Alcoólica , Adulto , Animais , Humanos , Camundongos , Dieta Hiperlipídica/efeitos adversos , Lipídeos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/etiologia , Obesidade/metabolismoRESUMO
Nonalcoholic fatty liver disease (NAFLD) is emerging as a leading cause of chronic liver disease worldwide. Despite intensive nonclinical and clinical research in this field, no specific pharmacological therapy is currently approved to treat NAFLD, which has been recognized as one of the major unmet medical needs of the 21st century. Our recent studies have identified STE20-type kinase MST3, which localizes to intracellular lipid droplets, as a critical regulator of ectopic fat accumulation in human hepatocytes. Here, we explored whether treatment with Mst3-targeting antisense oligonucleotides (ASOs) can promote hepatic lipid clearance and mitigate NAFLD progression in mice in the context of obesity. We found that administration of Mst3-targeting ASOs in mice effectively ameliorated the full spectrum of high-fat diet-induced NAFLD including liver steatosis, inflammation, fibrosis, and hepatocellular damage. Mechanistically, Mst3 ASOs suppressed lipogenic gene expression, as well as acetyl-CoA carboxylase (ACC) protein abundance, and substantially reduced lipotoxicity-mediated oxidative and endoplasmic reticulum stress in the livers of obese mice. Furthermore, we found that MST3 protein levels correlated positively with the severity of NAFLD in human liver biopsies. In summary, this study provides the first in vivo evidence that antagonizing MST3 signaling is sufficient to mitigate NAFLD progression in conditions of excess dietary fuels and warrants future investigations to assess whether MST3 inhibitors may provide a new strategy for the treatment of patients with NAFLD.
Assuntos
Dieta Hiperlipídica/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Obesidade/complicações , Oligonucleotídeos Antissenso/genética , Estresse Oxidativo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Animais , Lipogênese , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Proteínas Serina-Treonina Quinases/genética , Transdução de SinaisRESUMO
Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are emerging as leading causes of liver disease worldwide and have been recognized as one of the major unmet medical needs of the 21st century. Our recent translational studies in mouse models, human cell lines, and well-characterized patient cohorts have identified serine/threonine kinase (STK)25 as a protein that coats intrahepatocellular lipid droplets (LDs) and critically regulates liver lipid homeostasis and progression of NAFLD/NASH. Here, we studied the mechanism-of-action of STK25 in steatotic liver by relative quantification of the hepatic LD-associated phosphoproteome from high-fat diet-fed Stk25 knockout mice compared with their wild-type littermates. We observed a total of 131 proteins and 60 phosphoproteins that were differentially represented in STK25-deficient livers. Most notably, a number of proteins involved in peroxisomal function, ubiquitination-mediated proteolysis, and antioxidant defense were coordinately regulated in Stk25-/- versus wild-type livers. We confirmed attenuated peroxisomal biogenesis and protection against oxidative and ER stress in STK25-deficient human liver cells, demonstrating the hepatocyte-autonomous manner of STK25's action. In summary, our results suggest that regulation of peroxisomal function and metabolic stress response may be important molecular mechanisms by which STK25 controls the development and progression of NAFLD/NASH.
Assuntos
Fígado Gorduroso/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Gotículas Lipídicas/enzimologia , Peroxissomos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Estresse Fisiológico , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Serina-Treonina Quinases/deficiênciaRESUMO
Ectopic lipid storage in the liver is considered the main risk factor for nonalcoholic steatohepatitis (NASH). Understanding the molecular networks controlling hepatocellular lipid deposition is therefore essential for developing new strategies to effectively prevent and treat this complex disease. Here, we describe a new regulator of lipid partitioning in human hepatocytes: mammalian sterile 20-like (MST) 3. We found that MST3 protein coats lipid droplets in mouse and human liver cells. Knockdown of MST3 attenuated lipid accumulation in human hepatocytes by stimulating ß-oxidation and triacylglycerol secretion while inhibiting fatty acid influx and lipid synthesis. We also observed that lipogenic gene expression and acetyl-coenzyme A carboxylase protein abundance were reduced in MST3-deficient hepatocytes, providing insight into the molecular mechanisms underlying the decreased lipid storage. Furthermore, MST3 expression was positively correlated with key features of NASH (i.e., hepatic lipid content, lobular inflammation, and hepatocellular ballooning) in human liver biopsies. In summary, our results reveal a role of MST3 in controlling the dynamic metabolic balance of liver lipid catabolism vs. lipid anabolism. Our findings highlight MST3 as a potential drug target for the prevention and treatment of NASH and related complex metabolic diseases.-Cansby, E., Kulkarni, N. M., Magnusson, E., Kurhe, Y., Amrutkar, M., Nerstedt, A., Ståhlman, M., Sihlbom, C., Marschall, H.-U., Borén, J., Blüher, M., Mahlapuu, M. Protein kinase MST3 modulates lipid homeostasis in hepatocytes and correlates with nonalcoholic steatohepatitis in humans.
Assuntos
Hepatócitos/metabolismo , Proteínas Associadas a Gotículas Lipídicas/fisiologia , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Animais , Compartimento Celular , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/farmacocinética , Feminino , Técnicas de Silenciamento de Genes , Homeostase , Humanos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Hepáticas/metabolismo , Especificidade de Órgãos , Oxirredução , Estresse Oxidativo , Proteínas Serina-Treonina Quinases/análise , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Ratos , Triglicerídeos/metabolismoRESUMO
Several preclinical studies have revealed antidepressant and anxiolytic-like effect of 5-HT3 receptor antagonists. In our earlier study, we have reported the antidepressive-like effect of 3-methoxy-N-p-tolylquinoxalin-2-carboxamide (QCM-4) in obese mice subjected to chronic stress. The present study deals with the biochemical mechanisms associated with depression co-morbid with obesity. Mice were fed with high fat diet (HFD) for 14 weeks, further subjected for treatment with QCM-4 (1 and 2mg/kg p.o.) and standard antidepressant escitalopram (ESC) (10mg/kg p.o.) for 28 days. Behavioral assays for depression such as sucrose preference test (SPT), forced swim test (FST) and for anxiety such as light and dark test (LDT) and hole board test (HBT) were performed in obese mice. Biochemical assessments including plasma leptin and corticosterone concentration followed by brain oxidative stress parameters malonaldehyde (MDA) and reduced glutathione (GSH) were performed. Results confirmed that QCM-4 exhibits antidepressive effect by increasing the sucrose consumption in SPT, reducing immobility time in FST and anxiolytic effect by increasing transitions and time in light chamber in LDT, increasing head dip and crossing score in HBT. Furthermore, QCM-4 attenuated the hypothalamic-pituitary-adrenal (HPA) axis hyperactivity by reducing the plasma corticosterone, reversing altered plasma leptin, restoring the imbalance of brain MDA and GSH concentration. In conclusion, QCM-4 showed antidepressive and anxiolytic effect by reversing the behavioral alterations that were supported by biochemical estimations in obese mice.
Assuntos
Antidepressivos/farmacologia , Ansiedade/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Depressão/tratamento farmacológico , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Leptina/química , Estresse Oxidativo , Antagonistas do Receptor 5-HT3 de Serotonina/farmacologia , Corticosteroides/sangue , Ração Animal , Animais , Encéfalo/metabolismo , Gorduras na Dieta , Glutationa/metabolismo , Masculino , Malondialdeído/metabolismo , Aprendizagem em Labirinto , Camundongos , Camundongos Obesos , Quinoxalinas/farmacologia , Sacarose , NataçãoRESUMO
CONTEXT: Metabolic syndrome and non-alcoholic fatty liver disease (NAFLD) are the emerging co-morbidities of skin inflammation. Occurrence of skin inflammation such as psoriasis is substantially higher in NAFLD patients than normal. Currently, there are no animal models to study the interaction between these co-morbidities. OBJECTIVE: The present study seeks to develop a simple mouse model of NAFLD-enhanced skin inflammation and to study the effect of NAFLD on different parameters of skin inflammation. MATERIALS AND METHOD: Metabolic syndrome and NAFLD were induced in C57BL/6 mice by feeding high-fat diet (HFD, 60% kcal) and high fructose liquid (HFL, 40% kcal) in drinking water. Skin inflammation was induced by repeated application of oxazolone (1% sensitization and repeated 0.5% challenge) in both normal and NAFLD mice and various parameters of skin inflammation and NAFLD were measured. RESULTS: HFD and HFL diet induced obesity, hyperglycemia, hyperinsulinemia, and histological features of NAFLD in mice. Oxazolone challenge significantly increased ear thickness, ear weight, MPO activity, NF-κB activity, and histological features of skin inflammation in NAFLD mice as compared with normal mice. Overall, induction of oxazolone-induced skin inflammation was more prominent in NAFLD mice than normal mice. Hence, HFD and HFL diet followed by topical oxazolone application develops metabolic syndrome, NAFLD, and enhanced skin inflammation in mice. DISCUSSION AND CONCLUSION: This simple model can be utilized to evaluate a therapeutic strategy for the treatment of metabolic syndrome and NAFLD with skin inflammation and also to understand the nexus between these co-morbidities.
Assuntos
Dermatite/metabolismo , Modelos Animais de Doenças , Síndrome Metabólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Dermatite/etiologia , Dermatite/patologia , Dieta Hiperlipídica/efeitos adversos , Masculino , Síndrome Metabólica/etiologia , Síndrome Metabólica/patologia , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/patologiaRESUMO
The biological mechanisms that link the development of depression to metabolic disorders such as obesity and diabetes remain ambiguous. In the present study the potential of a selective cyclooxygenase inhibitor celecoxib (15 mg/kg p.o.) was investigated in depression associated with obesity in mice. Behavioral tests used to assess depressive-like behavior were sucrose preference test, forced swim test (FST), tail suspension test (TST) and elevated plus maze (EPM). The basal locomotor score in obese mice was not altered. Furthermore, estimation of biochemical parameters was performed for plasma glucose, total cholesterol, triglycerides and total proteins. Escitalopram (10 mg/kg p.o.) served as reference standard drug. In the results, chronic treatment with celecoxib for 28 days significantly attenuated the behavioral alterations as indicated by increased the sucrose consumption, reduced the immobility time in FST and TST, increased the percent open arm time and entries in EPM in obese mice. In the biochemical parameters celecoxib significantly reversed the increased plasma glucose, total cholesterol, triglycerides and total proteins in obese mice. In conclusion, celecoxib exhibited potential antidepressant-like effect in depression associated with obesity, which to some extent is mediated by reversing the altered plasma glucose in obese mice.
Assuntos
Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Depressão/tratamento farmacológico , Atividade Motora/efeitos dos fármacos , Obesidade/tratamento farmacológico , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico , Animais , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Celecoxib , Inibidores de Ciclo-Oxigenase 2/farmacologia , Depressão/metabolismo , Depressão/psicologia , Masculino , Camundongos , Atividade Motora/fisiologia , Obesidade/metabolismo , Obesidade/psicologia , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Resultado do TratamentoRESUMO
AIM: To investigate the antidepressant-like effects of a novel 5-HT3 receptor antagonist N-(benzo[d]thiazol-2-yl)-3-methoxyquinoxalin-2-carboxamide (6z) in acute and chronic murine models of depression. METHODS: 5-HT3 receptor antagonism was examined in guinea pig ileum in vitro. A tail suspension test (TST) was used as acute depression model to evaluate the antidepressant-like behavior in mice treated with 6z (0.5-2 mg/kg, ip). In chronic depression model, mice were exposed to a 4-week chronic unpredictable stress (CUS) protocol, and treated with 6z (0.5-2 mg·kg(-1)·d(-1), po) or a positive drug fluoxetine (10 mg·kg(-1)·d(-1), po) in the last 2 weeks, followed by behavioral and biochemical assessments. RESULTS: The 5-HT3 receptor antagonism of 6z (pA2=7.4) in guinea pig ileum was more potent than that of a standard 5-HT3 receptor antagonist ondansetron (pA2=6.9). In acute depression model, 6z administration significantly decreased the immobility duration. In chronic depression model, 6z administration reversed CUS-induced depressive-like behavior, as evidenced by increased immobility duration in the forced swim test and sucrose preference in the sucrose preference test. Furthermore, chronic administration of 6z prevented CUS-induced brain oxidative stress, with significant reduction of pro-oxidant markers and elevation of antioxidant enzyme activity. Moreover, chronic administration of 6z attenuated CUS-induced hypothalamic-pituitary-adrenal axis hyperactivity, as shown by reduced plasma corticosterone levels. Similar results were observed in the fluoxetine-treated group. CONCLUSION: 6z is a novel 5-HT3 receptor antagonist with potential antidepressant-like activities, which may be related to modulating hypothalamic-pituitary-adrenal axis and attenuating brain oxidative damage.
Assuntos
Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Benzotiazóis/farmacologia , Encéfalo/efeitos dos fármacos , Depressão/tratamento farmacológico , Quinoxalinas/farmacologia , Receptores 5-HT3 de Serotonina/efeitos dos fármacos , Antagonistas do Receptor 5-HT3 de Serotonina/farmacologia , Doença Aguda , Animais , Antioxidantes/metabolismo , Biomarcadores/sangue , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Doença Crônica , Corticosterona/sangue , Depressão/sangue , Depressão/fisiopatologia , Depressão/psicologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Comportamento Alimentar/efeitos dos fármacos , Feminino , Fluoxetina/farmacologia , Cobaias , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipotálamo-Hipofisário/fisiopatologia , Íleo/efeitos dos fármacos , Íleo/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Sistema Hipófise-Suprarrenal/fisiopatologia , Receptores 5-HT3 de Serotonina/metabolismoRESUMO
Clinical and preclinical data suggest that diabetes is often associated with anxiety. Insulin, a peptide hormone has been reported to have key functions in the brain and in alleviating several psychological impairments, occur as a consequence of diabetes. However, its effects in diabetes-induced anxiety are scanty. The present study examined whether; insulin can reverse the anxiety-like behavior in streptozotocin (STZ)-induced diabetes in mice. After 8-weeks of diabetes induced by STZ (200 mg/kg, intraperitoneally (i.p.)), mice were given insulin (1-2 IU/kg/day, i.p.)/ diazepam (1 mg/kg/day, i.p.)/ vehicle for 14 days and evaluated for behavioral effects in three validated models of anxiety viz. elevated plus maze (EPM), light-dark (L/D) and hole board (HB) tests. STZ-induced diabetic mice elicited significant behavioral effects which include, decreased percentage open arm entries and time in EPM, reduced latency and time spent in light chamber in L/D, decreased number of head dips, squares crossed and rearings in HB tests respectively. Insulin treatment attenuated the behavioral effects evoked by STZ-induced diabetes in mice as indicated by increased open arms activity in EPM, decreased aversion in light chamber during L/D test and increased exploratory behavior in HB test. In conclusion, this study revealed that insulin can reverse anxiety-like behavior in STZ-induced diabetes in mice.
Assuntos
Ansiolíticos/farmacologia , Ansiedade/tratamento farmacológico , Comportamento Animal/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Insulina/farmacologia , Animais , Ansiolíticos/uso terapêutico , Ansiedade/etiologia , Glicemia , Diabetes Mellitus Experimental/tratamento farmacológico , Diazepam/farmacologia , Diazepam/uso terapêutico , Comportamento Exploratório/efeitos dos fármacos , Feminino , Insulina/uso terapêutico , Masculino , Camundongos , Atividade Motora/efeitos dos fármacosRESUMO
The aim of the present work was to investigate the role of ondansetron on the high fat diet (HFD) induced obese mice for behavioral and biochemical alterations using chronic unpredictable mild stress (CUMS) model of depression. Animals were fed with high fat diet for 14 weeks and subjected to different stress procedures for 4 weeks. Treatment with ondansetron was started on day 15. After day 28 behavioral assays and biochemical estimations were performed. Behavioral paradigms viz. sucrose preference test, locomotor score, forced swim test (FST) and elevated plus maze (EPM), whereas biochemical parameters like plasma glucose, total cholesterol, triglycerides and total proteins were estimated. Results examines that in behavioral assays, ondansetron significantly (P < 0.05) increased sucrose consumption, reduced immobility time in FST, increased the percent entries and time in open arm in EPM. In biochemical assessments elevated plasma glucose, total cholesterol, triglycerides and total proteins were significantly (P < 0.05) reversed by ondansetron treatment in HFD obese animals subjected to CUMS. The study indicates that the obese mice subjected to CUMS exhibited severe depressive-like symptoms and ondansetron significantly reversed the behavioral and biochemical alterations. In the present study the plasma glucose level indicates that, it could be "altered glucose level" playing an important role in depression co-morbid with obesity. Ondansetron through allosteric modulation of serotonergic system elevates the serotonin level and thereby regulates the insulin secretion and hence, reversing the "altered glucose level", could be the possible antidepressive-like mechanism against depression co-morbid with obesity.
Assuntos
Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Transtorno Depressivo/tratamento farmacológico , Obesidade/complicações , Ondansetron/farmacologia , Animais , Antidepressivos/uso terapêutico , Glicemia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Depressão/complicações , Depressão/metabolismo , Transtorno Depressivo/complicações , Transtorno Depressivo/metabolismo , Dieta Hiperlipídica , Lipídeos/sangue , Masculino , Camundongos , Camundongos Obesos , Atividade Motora/efeitos dos fármacos , Obesidade/metabolismo , Ondansetron/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Estresse Psicológico/metabolismo , NataçãoRESUMO
BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is one of the most fatal and fastest-growing cancers. Recently, nonalcoholic steatohepatitis (NASH) has been recognized as a major catalyst for HCC. Thus, additional research is critically needed to identify mechanisms involved in NASH-induced hepatocarcinogenesis, to advance the prevention and treatment of NASH-driven HCC. Because the sterile 20-type kinase serine/threonine kinase 25 (STK25) exacerbates NASH-related phenotypes, we investigated its role in HCC development and aggravation in this study. METHODS: Hepatocarcinogenesis was induced in the context of NASH in Stk25 knockout and wild-type mice by combining chemical procarcinogens and a dietary challenge. In the first cohort, a single injection of diethylnitrosamine was combined with a high-fat diet-feeding. In the second cohort, chronic administration of carbon tetrachloride was combined with a choline-deficient L-amino-acid-defined diet. To study the cell-autonomous mode of action of STK25, we silenced this target in the human hepatocarcinoma cell line HepG2 by small interfering RNA. RESULTS: In both mouse models of NASH-driven HCC, the livers from Stk25-/- mice showed a markedly lower tumor burden compared with wild-type controls. We also found that genetic depletion of STK25 in mice suppressed liver tumor growth through reduced hepatocellular apoptosis and decreased compensatory proliferation, by a mechanism that involves protection against hepatic lipotoxicity and inactivation of STAT3, ERK1/2, and p38 signaling. Consistently, silencing of STK25 suppressed proliferation, apoptosis, migration, and invasion in HepG2 cells, which was accompanied by lower expression of the markers of epithelial-mesenchymal transition and autophagic flux. CONCLUSIONS: This study provides evidence that antagonizing STK25 signaling hinders the development of NASH-related HCC and provides an impetus for further analysis of STK25 as a therapeutic target for NASH-induced HCC treatment in human beings.
Assuntos
Carcinoma Hepatocelular , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Proteínas Serina-Treonina Quinases , Animais , Carcinoma Hepatocelular/patologia , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/patologia , Oncogenes , Proteínas Serina-Treonina Quinases/genéticaRESUMO
High-risk neuroblastoma (NB) often involves MYCN amplification as well as mutations in ALK. Currently, high-risk NB presents significant clinical challenges, and additional therapeutic options are needed. Oncogenes like MYCN and ALK result in increased replication stress in cancer cells, offering therapeutically exploitable options. We have pursued phosphoproteomic analyses highlighting ATR activity in ALK-driven NB cells, identifying the BAY1895344 ATR inhibitor as a potent inhibitor of NB cell growth and proliferation. Using RNA-Seq, proteomics and phosphoproteomics we characterize NB cell and tumour responses to ATR inhibition, identifying key components of the DNA damage response as ATR targets in NB cells. ATR inhibition also produces robust responses in mouse models. Remarkably, a 2-week combined ATR/ALK inhibition protocol leads to complete tumor regression in two independent genetically modified mouse NB models. These results suggest that NB patients, particularly in high-risk groups with oncogene-induced replication stress, may benefit from ATR inhibition as therapeutic intervention.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Neuroblastoma/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Quinase do Linfoma Anaplásico/genética , Quinase do Linfoma Anaplásico/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , Dano ao DNA , Reparo do DNA , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Morfolinas/farmacologia , Morfolinas/uso terapêutico , Neuroblastoma/genética , Neuroblastoma/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/farmacologia , Pirazóis/uso terapêutico , RNA-Seq , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Nonalcoholic fatty liver disease (NAFLD) has emerged as a leading cause of chronic liver disease worldwide, primarily because of the massive global increase in obesity. Despite intense research efforts in this field, the factors that govern the initiation and subsequent progression of NAFLD are poorly understood, which hampers the development of diagnostic tools and effective therapies in this area of high unmet medical need. Here we describe a regulator in molecular pathogenesis of NAFLD: STE20-type protein kinase MST4. We found that MST4 expression in human liver biopsies was positively correlated with the key features of NAFLD (i.e., hepatic steatosis, lobular inflammation, and hepatocellular ballooning). Furthermore, the silencing of MST4 attenuated lipid accumulation in human hepatocytes by stimulating ß-oxidation and triacylglycerol secretion, while inhibiting fatty acid influx and lipid synthesis. Conversely, overexpression of MST4 in human hepatocytes exacerbated fat deposition by suppressing mitochondrial fatty acid oxidation and triacylglycerol efflux, while enhancing lipogenesis. In parallel to these reciprocal alterations in lipid storage, we detected substantially decreased or aggravated oxidative/endoplasmic reticulum stress in human hepatocytes with reduced or increased MST4 levels, respectively. Interestingly, MST4 protein was predominantly associated with intracellular lipid droplets in both human and rodent hepatocytes. Conclusion: Together, our results suggest that hepatic lipid droplet-decorating protein MST4 is a critical regulatory node governing susceptibility to NAFLD and warrant future investigations to address the therapeutic potential of MST4 antagonism as a strategy to prevent or mitigate the development and aggravation of this disease.
RESUMO
INTRODUCTION: Obesity is an important risk factor for depression as more than half of the obese population is susceptible for depression at double rate. Our earlier studies reported the antidepressant potential of 5-HT3 receptor antagonist, ondansetron (OND) in depression associated obesity using behavioral tasks. The present research work is aimed to evaluate the effect of OND on depression associated with obesity with special emphasis on biochemical and molecular mechanisms such as hippocampal brain-derived neurotrophic factor (BDNF), cyclic adenosine monophosphate (cAMP), 5-hydroxytryptamine (5-HT), hippocampal histological examination and immunohistochemical expression of p53 proteins. MATERIALS AND METHODS: Mice were fed with high-fat diet (HFD) for 14 weeks, followed by treatment schedule for 28 days with vehicle/OND (0.5 and 1 mg/kg, p.o.)/reference antidepressant escitalopram (10 mg/kg, p.o.). Subsequently, animals were screened in the behavioral tests of depression such as forced swim test (FST) and sucrose preference test (SPT), biochemical estimations including hippocampal cAMP, BDNF and 5-HT, and molecular assays mainly histology and p53 expression of dentate gyrus (DG). RESULTS: HFD-fed mice showed increased immobility time in FST, reduced sucrose consumption in SPT, decreased level of signal transduction factor cAMP, neuronal growth factor BDNF and neurotransmitter 5-HT in the hippocampus, and raised and p53 expression neuronal damage in the DG region of mice fed with HFD in comparison to the mice fed with normal pellet diet. Chronic treatment with OND (0.5 and 1 mg/kg, p.o.) significantly inhibited the behavioral, biochemical and molecular modifications in HFD-fed mice. CONCLUSION: In the preliminary study, OND attenuated depression associated with obesity in mice fed with HFD using various assays procedures, at least in part by the modulation of serotonergic transmission.
Assuntos
Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Dieta Hiperlipídica/efeitos adversos , Hipocampo/metabolismo , Atividade Motora/fisiologia , Obesidade/tratamento farmacológico , Animais , Antidepressivos/farmacologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Depressão/metabolismo , Depressão/psicologia , Hipocampo/efeitos dos fármacos , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Obesidade/metabolismo , Obesidade/psicologia , Antagonistas do Receptor 5-HT3 de Serotonina/farmacologia , Antagonistas do Receptor 5-HT3 de Serotonina/uso terapêutico , Natação/fisiologia , Natação/psicologiaRESUMO
RATIONALE: Depression associated with obesity remains an interesting area to study the biological mechanisms and novel therapeutic intervention. OBJECTIVES: The present study investigates the effect of a novel 5-HT3 receptor antagonist 3-methoxy-N-p-tolylquinoxalin-2-carboxamide (QCM-4) on several pathogenic markers of depression associated with obesity such as plasma insulin resistance, hippocampal cyclic adenosine monophosphate (cAMP), brain-derived neurotrophic factor (BDNF), serotonin (5-HT) concentrations, hippocampal neuronal damage, and p53 protein expression in high-fat-diet (HFD)-fed mice. METHODS: Obesity was experimentally induced in mice by feeding with HFD for 14 weeks followed by administration of QCM-4 (1 and 2 mg/kg, p.o.)/standard escitalopram (ESC) (10 mg/kg, p.o.)/vehicle (10 ml/kg, p.o.) for 28 days. Behavioral assays such as sucrose preference test (SPT); forced swim test (FST); elevated plus maze (EPM); biochemical assays including oral glucose tolerance tests (OGTT), insulin, cAMP, BDNF, and 5-HT concentrations; and molecular assays mainly histology and immunohistochemistry (IHC) of p53 protein in the dentate gyrus (DG), CA1, and CA3 regions of hippocampus in HFD fed mice were performed. RESULTS: Chronic treatment with QCM-4 in HFD-fed mice reversed the behavioral alterations in SPT, FST, and EPM. QCM-4 showed poor sensitivity for plasma glucose, improved insulin sensitivity, increased hippocampal cAMP, BDNF, and 5-HT concentrations. In the hippocampal DG, CA1, and CA3 regions, QCM-4 treatment improved the neuronal morphology in the histopathology and inhibited p53 protein expression in IHC assay in HFD-fed mice. CONCLUSION: QCM-4 attenuated the depressive-like phenotype in HFD-fed mice by improving behavioral, biochemical, and molecular alterations through serotonergic neuromodulation.
Assuntos
Depressão/tratamento farmacológico , Obesidade/psicologia , Quinoxalinas/uso terapêutico , Antagonistas do Receptor 5-HT3 de Serotonina/uso terapêutico , Animais , Ansiedade/tratamento farmacológico , Ansiedade/psicologia , Química Encefálica/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/complicações , Depressão/psicologia , Dieta Hiperlipídica , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Resistência à Insulina , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Serotonina/metabolismo , Natação/psicologia , Proteína Supressora de Tumor p53/metabolismoRESUMO
Pioglitazone, a peroxisome proliferator activated receptor gamma (PPARγ) agonist belonging to thiazolidinedione class, is mainly used in diabetes mellitus. Obese subjects are twice likely to become depressed than non-obese individuals. The biological mechanisms linking depression with obesity still remain poorly understood and there is immense need for better therapeutic intervention against such co-morbid disorders. The present study investigates the effect of pioglitazone on the chronic unpredictable mild stress (CUMS) induced depression in obese mice by using behavioral tests and biochemical estimations. Mice were fed with high fat diet (HFD) for 14 weeks and were further subjected to different stress procedures for 28 days to induce depressive behavior. Animals were administered orally with pioglitazone (30 mg/kg p.o.)/escitalopram (10 mg/kg p.o.)/vehicle (10 ml/kg p.o.) daily from day 15-28. Various behavioral paradigms such as sucrose preference test, forced swim test (FST), tail suspension test (TST) and elevated plus maze (EPM) were performed. Biochemical estimations including plasma glucose, total cholesterol, triglycerides, and total proteins were performed. The data obtained from behavioral assays and biochemical assessments indicated that obese animals exhibited severe depressive-like behavior compared to non-obese animals. Furthermore, obese animals subjected to CUMS worsen the depressive behavior compared to obese control animals. Repetitive treatment with pioglitazone reversed the CUMS induced behavioral and biochemical alterations in HFD fed obese mice which atleast in part may be mediated through improving altered plasma glucose. The study suggests that pioglitazone needs further attention with respect to molecular mechanisms that could provide a better therapeutic strategy against depression associated with obesity.
RESUMO
In our earlier study we reported the antidepressant activity of ondansetron in obese mice. The present study investigates the effect of ondansetron on depression and anxiety associated with obesity in experimental mice with biochemical evidences. Male Swiss albino mice were fed with high fat diet (HFD) for 14weeks to induce obesity. Then the subsequent treatment with ondansetron (0.5 and 1mg/kg, p.o.), classical antidepressant escitalopram (ESC) (10mg/kg, p.o.) and vehicle (distilled water 10ml/kg, p.o.) was given once daily for 28days. Behavioral assay for depression including sucrose preference test, forced swim test (FST) and anxiety such as light dark test (LDT) and hole board test (HBT) were performed in obese mice. Furthermore, in biochemical estimations oral glucose tolerance test (OGTT), plasma leptin, insulin, corticosterone, brain oxidative stress marker malonaldehyde (MDA), antioxidant reduced glutathione (GSH) and serotonin assays were performed. Results indicated that HFD fed obese mice showed severe depressive and anxiety-like behaviors. Chronic treatment with ondansetron inhibited the co-morbid depression and anxiety in obese mice by increasing sucrose consumption in sucrose preference test and reducing the immobility time in FST, increasing time and transitions of light chamber in LDT, improving head dip and crossing scores in HBT compared to HFD control mice. Ondansetron in obese mice inhibited glucose sensitivity in OGTT, improved plasma leptin and insulin sensitivity, reversed hypothalamic pituitary adrenal (HPA) axis hyperactivity by reducing the corticosterone concentration, restored brain pro-oxidant/anti-oxidant balance by inhibiting MDA and elevating GSH concentrations and facilitated serotonergic neurotransmission. In conclusion, ondansetron reversed the co-morbid depression and anxiety associated with obesity in experimental mice by attenuating the behavioral and biochemical abnormalities.
Assuntos
Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Depressão/tratamento farmacológico , Depressão/metabolismo , Obesidade/complicações , Ondansetron/farmacologia , Serotonina/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Animais , Ansiedade/sangue , Ansiedade/complicações , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Citalopram/farmacologia , Corticosterona/sangue , Depressão/sangue , Depressão/complicações , Dieta Hiperlipídica , Teste de Tolerância a Glucose , Glutationa/metabolismo , Insulina/sangue , Leptina/sangue , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Obesos , Obesidade/metabolismo , Ondansetron/uso terapêutico , Estresse Oxidativo/efeitos dos fármacosRESUMO
Despite of the enormous research, therapeutic treatment for depression has always been a serious issue. Even though depression and obesity are individual abnormal health conditions, each act as a triggering factor for the other. Obese individuals are twice prone to develop depression than that of non-obese persons. The exact mechanism how obesity increases the risk for depression still remains an area of interest for research in neuropsychopharmacology. Depression and obesity share some common pathological pathways such as hyperactivity of hypothalamic-pituitary-adrenal (HPA) axis, dysregulation of oxidant/antioxidant system balance, higher level of inflammatory cytokines, leptin resistance, altered plasma glucose, insulin resistance, reduced neuronal brain derived neurotrophic factor (BDNF) and decreased serotonergic neurotransmission in various regions of brain. The antidepressant-like effect of 5-HT3 receptor antagonists through allosteric modulation of serotonergic pathways is well evident from several research investigations belonging to our and some in other laboratories. Furthermore, serotonin regulates diet intake, leptin, corticosterone, inflammatory mechanisms, altered plasma glucose, insulin resistance and BDNF concentration in brain. The present review deals with various biological mechanisms involved in depression co-morbid with obesity and 5-HT3 receptor antagonists by modulation of serotonergic system as a therapeutic target for such co-morbid disorder.
Assuntos
Transtorno Depressivo , Obesidade , Antagonistas do Receptor 5-HT3 de Serotonina/farmacologia , Transmissão Sináptica/efeitos dos fármacos , Animais , Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Comorbidade , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/metabolismo , Transtorno Depressivo/fisiopatologia , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Inflamação/metabolismo , Resistência à Insulina , Obesidade/epidemiologia , Obesidade/metabolismo , Obesidade/psicologia , Estresse Oxidativo , Sistema Hipófise-Suprarrenal/metabolismoRESUMO
Stress in our daily life severely affects the normal physiology of the biological system. Dysregulation of hypothalamic-pituitary-adrenal (HPA) axis has been implicated in the development of depression-like behavior, which remains under diagnosed and poorly treated. Exogenous corticosterone (CORT) administration has been demonstrated to develop a depression model, which has shown to mimic HPA-axis induced depression-like state in rodents. In the present study, the effect of a novel 5HT3 receptor, 4i was examined on CORT induced depression in mice. CORT (30mg/kg, subcutaneously) was given for 4-weeks to mice in control group, while mice in drug treated group were given 4i (0.5-1mg/kg, intraperitoneally)/fluoxetine (as a positive control, 10mg/kg), for the last 2-weeks of CORT dosing. Repeated CORT dosing caused depression-like behavior in mice as indicated by increased despair effects in forced swim test (FST) and anhedonia in sucrose preference test. In addition, CORT administration induced oxidative load in the brain with significant increase in pro-oxidant (lipid peroxidation and nitrite levels) markers and a substantial decline in anti-oxidant defense (catalase and reduced glutathione levels) system, indicating a direct effect of stress hormones in the induction of the brain oxidative damage. On the other hand, 4i and fluoxetine treatment reversed the CORT induced depressive-like deficits. Furthermore, 4i and fluoxetine prevented CORT induced oxidative brain insults, which may plausibly demonstrate one of the key mechanisms for antidepressant-like effects of the compounds. Thus, the study suggests that 5HT3 antagonist; 4i may be implicated as pharmacological intervention targeting depressive-like anomaly associated with HPA-axis dysregulation.