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2.
Cell Death Dis ; 8(7): e2926, 2017 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-28703798

RESUMO

mTORC2 is aberrantly activated in cancer and therefore is considered to be an important therapeutic target. The hedgehog pathway, which is also often hyperactivated, regulates transcription of several genes associated with angiogenesis, metastasis, cellular proliferation and cancer stem cell (CSC) regeneration. However, the contribution of mTORC2 toward hedgehog pathway activity has not been explored yet. Here we have addressed the molecular cross talk between mTORC2 and hedgehog pathway activities in the context of glioblastoma multiforme, a malignant brain tumor using as a model system. We observed that higher mTORC2 activity enhanced the expression of a few hedgehog pathway molecules (Gli1, Gli2 and Ptch1) and amplified its target genes (Cyclin D1, Cyclin D2, Cyclin E, Snail, Slug and VEGF) both in mRNA and protein levels as corroborated by increased metastasis, angiogenesis, cellular proliferation and stem cell regeneration. Inhibition of mTORC2 formation decreased hedgehog pathway activity and attenuated all these above-mentioned events, suggesting their cross talk with each other. Further investigations revealed that mTORC2 inhibited ubiquitination of Gli2 by inactivating GSK3ß, and thus it promotes stability to Gli2 and its nuclear translocation. Moreover, enhanced mTORC2 activity led to the increased clonogenic properties and CD133+ cells, indicating its role in CSC regeneration. mTORC2 inhibitor directed the reduction of hedgehog pathway proteins and also reduced CSCs. Thus, our observations support a role for elevated mTORC2 activity in regulating angiogenesis, metastasis, cellular proliferation and CSC regeneration via hedgehog pathway activity. Taken together, it provides a rationale for including the mTOR2 inhibitor as part of the therapeutic regimen for CSCs.


Assuntos
Núcleo Celular/metabolismo , Proteínas Hedgehog/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteínas Nucleares/metabolismo , Transdução de Sinais , Proteína Gli2 com Dedos de Zinco/metabolismo , Carbazóis/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclina E/genética , Ciclina E/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Alvo Mecanístico do Complexo 2 de Rapamicina/antagonistas & inibidores , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Proteína Companheira de mTOR Insensível à Rapamicina/antagonistas & inibidores , Proteína Companheira de mTOR Insensível à Rapamicina/genética , Proteína Companheira de mTOR Insensível à Rapamicina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína GLI1 em Dedos de Zinco/genética , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína Gli2 com Dedos de Zinco/antagonistas & inibidores , Proteína Gli2 com Dedos de Zinco/genética
3.
Sci Rep ; 7(1): 4141, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28646156

RESUMO

Earlier we have established a carbazole alkaloid (mahanine) isolated from an Indian edible medicinal plant as an anticancer agent with minimal effect on normal cells. Here we report for the first time that mahanine-treated drug resistant and sensitive virulent Leishmania donovani promastigotes underwent apoptosis through phosphatidylserine externalization, DNA fragmentation and cell cycle arrest. An early induction of reactive oxygen species (ROS) suggests that the mahanine-induced apoptosis was mediated by oxidative stress. Additionally, mahanine-treated Leishmania-infected macrophages exhibited anti-amastigote activity by nitric oxide (NO)/ROS generation along with suppression of uncoupling protein 2 and Th1-biased cytokines response through modulating STAT pathway. Moreover, we have demonstrated the interaction of a few antioxidant enzymes present in parasite with mahanine through molecular modeling. Reduced genetic and protein level expression of one such enzyme namely ascorbate peroxidase was also observed in mahanine-treated promastigotes. Furthermore, oral administration of mahanine in acute murine model exhibited almost complete reduction of parasite burden, upregulation of NO/iNOS/ROS/IL-12 and T cell proliferation. Taken together, we have established a new function of mahanine as a potent antileishmanial molecule, capable of inducing ROS and exploit antioxidant enzymes in parasite along with modulation of host's immune response which could be developed as an inexpensive and nontoxic therapeutics either alone or in combination.


Assuntos
Carbazóis/farmacologia , Leishmania/efeitos dos fármacos , Leishmania/metabolismo , Oxirredução/efeitos dos fármacos , Tripanossomicidas/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Homeostase/efeitos dos fármacos , Humanos , Leishmaniose/tratamento farmacológico , Leishmaniose/parasitologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Moleculares , Conformação Molecular , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Tripanossomicidas/química
4.
Mol Genet Metab ; 119(3): 223-231, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27590926

RESUMO

Long-chain fatty acid oxidation disorders (LC-FAOD) can cause cardiac hypertrophy and cardiomyopathy, often presenting in infancy, typically leading to death or heart transplant despite ongoing treatment. Previous data on triheptanoin treatment of cardiomyopathy in LC-FAOD suggested a clinical benefit on heart function during acute failure. An additional series of LC-FAOD patients with critical emergencies associated with cardiomyopathy was treated with triheptanoin under emergency treatment or compassionate use protocols. Case reports from 10 patients (8 infants) with moderate or severe cardiomyopathy associated with LC-FAOD are summarized. The majority of these patients were detected by newborn screening, with follow up confirmatory testing, including mutation analysis; all patients were managed with standard treatment, including medium chain triglyceride (MCT) oil. While on this regimen, they presented with acute heart failure requiring hospitalization and cardiac support (ventilation, ECMO, vasopressors) and, in some cases, resuscitation. The patients discontinued MCT oil and began treatment with triheptanoin, an investigational drug. Triheptanoin is expected to provide anaplerotic metabolites, to replace deficient TCA cycle intermediates and improve effective energy metabolism. Cardiac function was measured by echocardiography and ejection fraction (EF) was assessed. EF was moderately to severely impaired prior to triheptanoin treatment, ranging from 12-45%. Improvements in EF began between 2 and 21days following initiation of triheptanoin, and peaked at 33-71%, with 9 of 10 patients achieving EF in the normal range. Continued treatment was associated with longer-term stabilization of clinical signs of cardiomyopathy. The most common adverse event observed was gastrointestinal distress. Of the 10 patients, 7 have continued on treatment, 1 elected to discontinue due to tolerability issues, and 2 patients died from other causes. Two of the case histories illustrate that cardiomyopathy may also develop later in childhood and/or persist into adulthood. Overall, the presented cases suggest a therapeutic effect of triheptanoin in the management of acute cardiomyopathy associated with LC-FAOD.


Assuntos
Cardiomiopatias/tratamento farmacológico , Erros Inatos do Metabolismo Lipídico/tratamento farmacológico , Triglicerídeos/administração & dosagem , Adolescente , Cardiomiopatias/complicações , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Erros Inatos do Metabolismo Lipídico/complicações , Erros Inatos do Metabolismo Lipídico/patologia , Masculino , Oxirredução/efeitos dos fármacos , Triglicerídeos/efeitos adversos
5.
Indian Pediatr ; 37(6): 691-2, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10869169
6.
Am J Med Genet ; 78(1): 44-51, 1998 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-9637422

RESUMO

We describe a complex and unique, de novo apparently balanced translocation involving chromosomes 4, 18, and 21 with 4 breakpoints, in a patient who was referred for an evaluation of possible fragile-X syndrome. Fluorescence in situ hybridization (FISH) confirmed the complexity of the rearrangement and showed the derivative 21 to be composed of 3 distinct segments derived from chromosomes 21, 18, and 4. The derivative chromosome 18 had undergone a double translocation, the first such event to be described in constitutional complex chromosomal rearrangements (CCRs) involving chromosome 18. A review of these CCRs suggests the existence of a breakpoint "hot spot" on 18q21.


Assuntos
Cromossomos Humanos Par 18 , Cromossomos Humanos Par 21 , Cromossomos Humanos Par 4 , Deficiência Intelectual/genética , Translocação Genética , Pré-Escolar , Feminino , Humanos , Hibridização in Situ Fluorescente
7.
Ophthalmic Genet ; 16(4): 171-5, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8749054

RESUMO

The authors present a case report of Duane retraction syndrome (DRS) associated with Rubinstein-Taybi syndrome (RTS). RTS is a multisystem condition characterized by psychomotor developmental delay, broad thumbs and great toes, short stature, and characteristic facies with a beaked nose. DRS is an ocular disorder characterized by retraction of the globe with narrowing of the palpebral fissure in attempted adduction, with abduction and/or adduction deficiency, and, frequently, upshoot or downshoot of the affected eye on adduction. The case report described represents the first reported case of DRS associated with RTS, an association not previously recognized. This association raises the possibility that the abnormal CNS development in RTS may occasionally involve the ocular motor nerves.


Assuntos
Síndrome da Retração Ocular/etiologia , Síndrome de Rubinstein-Taybi/complicações , Criança , Síndrome da Retração Ocular/patologia , Feminino , Humanos , Cariotipagem , Síndrome de Rubinstein-Taybi/patologia
8.
Obstet Gynecol ; 71(6 Pt 2): 988-91, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3287253

RESUMO

We report the first prenatal identification using ultrasound of a fetus affected with spondylocostal dysplasia type I, or Jarcho-Levin syndrome, in a patient without a positive family history for this condition. The fetus was initially evaluated because of a low maternal serum alpha-fetoprotein determination. At 23 weeks, we visualized a shortened spine, disorganization of the vertebral bodies, posterior fusion of the ribs, and normal long-bone biometry. Termination of pregnancy was elected. All features identified with ultrasound were confirmed postnatally. The fetus was affected with Jarcho-Levin syndrome, a recessively inherited condition associated with a 25% recurrence rate.


Assuntos
Osteocondrodisplasias/diagnóstico , Diagnóstico Pré-Natal , Costelas/anormalidades , Coluna Vertebral/anormalidades , Ultrassonografia , Adulto , Feminino , Humanos , Fenótipo , Gravidez , Segundo Trimestre da Gravidez , Síndrome
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