Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Discov Nano ; 18(1): 154, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087141

RESUMO

Burn injuries are characterized by prolonged inflammatory phases, neurovascular damage, and hypermetabolism, eventually causing improper tissue regeneration. Insulin has gained considerable attention in normal and diabetic wound healing, yet its role in burn wounds remains poorly understood. In this study, insulin-chitosan nano-formulations (ICNP) were synthesized using a simple and robust mechanism and characterized to monitor specific interactions between insulin and chitosan, and the particles measuring approximately 30 nm in size exhibited mild alterations in the amide I, II, and III bonds of the insulin protein along with impressive insulin loading efficiency of 88.725 ± 0.295% under physiological conditions, and significantly improved burn wound healing in vitro (HEKa cells) and in vivo (murine third-degree burn model). The underlying mechanism behind superior wound closure and tissue remodeling was attributed to significant early phase reduction of pro-inflammatory cytokine IL-6 levels in ICNP-treated mice, while anti-inflammatory cytokine IL-10 levels became markedly elevated, resulting in enhanced re-epithelialization and collagen deposition. Furthermore, treatment of ICNP was associated with unregulated expression of Nrf-2, a key regulator of oxidative stress and inflammation, indicating their molecular crosstalk. These findings highlight the potential of ICNP as a promising therapeutic formulation for burn wound healing, promoting wound closure by modulating inflammatory phases, making it a valuable candidate for further clinical development in burn care.

2.
Ann Med Surg (Lond) ; 81: 104248, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35937633

RESUMO

Background: It was formerly thought that patients with a history of active cancer were more likely to acquire COVID-19; however, new research contradicts this belief due to the impact of economic stress, malnutrition, fear of hospitalization, or therapeutic discontinuation. A cohort-based study was undertaken in Indian regional cancer centre to understand cancer-covid link in patients. Method: A total of 1565 asymptomatic patients were admitted based on thermal screening and evaluation from the screening form from June 2020 to November 2020. The RT-PCR technology was used to assess the COVID 19, and patients who tested positive for COVID 19 were transported to a hospital designated by the government for COVID 19 patients. Patients who tested negative for the COVID 19 virus were transferred to the normal cancer unit to complete their treatment. Patients who tested positive for COVID 19 were referred to the COVID hospital, where their findings were analyzed and correlated with patient age, gender, and cancer stage. Findings: Out of 1565 patients, 54 patients (3.4%) tested positive. Most of the patients are in 45-59 years age group. As female patients admitted were more in number than males, so predominance of disease is higher in female. 3 patients were symptomatic after admission and 2 were severe and were admitted to the ICU with ventilations. 8 patients died in Cancer and one patient died in COVID 19. Interpretation: As only 3.4% patients tested positive and only one patient out of 54 had died, so cancer is found not to be a comorbid condition towards COVID 19 patients in the Indian population studied.Funding: This project is not funded.

3.
Sci Adv ; 8(10): eabh1419, 2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35275724

RESUMO

The short half-life in the GI tract necessitates an excess of drugs causing side effects of oral formulations. Here, we report the development and deployment of Bacterioboat, which consists of surface-encapsulated mesoporous nanoparticles on metabolically active Lactobacillus reuteri as a drug carrier suitable for oral administration. Bacterioboat showed up to 16% drug loading of its dry weight, intestinal anchorage around alveoli regions, sustained release, and stability in physiological conditions up to 24 hours. In vivo studies showed that oral delivery of 5-fluorouracil leads to increased potency, resulting in improved shrinkage of solid tumors, enhanced life expectancy, and reduced side effects. This novel design and development make this system ideal for orally administrable drugs with low solubility or permeability or both and even making them effective at a lower dose.


Assuntos
Portadores de Fármacos , Nanopartículas , Administração Oral , Sistemas de Liberação de Medicamentos , Meia-Vida , Solubilidade
4.
J Ethnopharmacol ; 282: 114627, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34509603

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dengue virus (DENV) is a re-emerging mosquito-borne flavivirus that has recently engendered large epidemics around the world. Consequently antivirals with effective anti-DENV therapeutic activity are urgently required. In the 18th century, Europeans, as well as native inhabitants of North America, were known to adapt the medicinal property of the common perennial plant Eupatorium perfoliatum L. to treat fever and infections. Previous studies have shown that Eupatorium perfoliatum L. possesses anti-inflammatory, anti-oxidative, anti-plasmodial, anti-bacterial and antiviral activities. However, to the best of our knowledge, no anti-DENV activity of E. perfoliatum L. has been investigated at the molecular level so far. AIM OF STUDY: Here, for the first time we have attempted to study the action of E. perfoliatum extract and its few bioactive components i.e., quercetin, caffeic acid and eupafolin against wild primary clinical isolate of DENV-2 infection in an in vitro model. MATERIALS AND METHODS: The presence of the bioactive components in the E. perfoliatum extract, were analyzed by HPLC- DAD. Then, CC50 as well as IC50 values of the extract and its bioactive components were measured against DENV in HepG2 cell line. After that, the antiviral activity was studied by Time of addition assay using qRT-PCR. Further, the downstream signalling action of E. perfoliatum extract, was studied by Human phosphorylation MAPK antibody array, followed by immunofluorescence microscopy. Moreover, a molecular docking analysis was done to study the binding affinity of bioactive components of E. perfoliatum extract with TIM-1 transmembrane receptor protein, which is known for viral internalization. RESULT: We found that E. perfoliatum extract has marked antiviral activity during pre-treatment against DENV infection in HepG2 cell line. The extract also significantly reduced the DENV induced autophagy in HepG2 cell line as detected by LC3 II localization. The presence of different bioactive compounds in E. perfoliatum extract were confirmed by HPLC-DAD. In the bioactive components, in parallel to earlier studies, quercetin showed the most significant preventive action against DENV infection. Further, in molecular docking analysis also, quercetin showed the strongest binding affinity towards DENV membrane receptor TIM-1 protein. CONCLUSION: Our findings suggests that E. perfoliatum extract has significant potential to be an anti-DENV therapeutic agent. Moreover, among the bioactive components, quercetin may have a prophylaxis role in executing the antiviral activity of E. perfoliatum extract against DENV infection.


Assuntos
Autofagia/efeitos dos fármacos , Vírus da Dengue/efeitos dos fármacos , Eupatorium/química , Extratos Vegetais/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Aedes , Animais , Antivirais/química , Antivirais/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Vírus da Dengue/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Fitoterapia , Extratos Vegetais/química , RNA Viral/genética , RNA Viral/metabolismo , Serina-Treonina Quinases TOR/genética , Cultura de Vírus , Replicação Viral/efeitos dos fármacos
5.
Front Microbiol ; 13: 1088477, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36741891

RESUMO

Introduction: Natural carotenoids are well known for their anti-oxidant property and also shown to have antimicrobial and anticancer efficacy. Production of carotenoids from microbial resources mainly from yeast has attracted commercial interest. Breast cancer has the highest incidence among women, and therapy resistance and lack of effective therapeutic strategies are major treatment bottlenecks, particularly for triple-negative subtypes. Yeast carotenoids are recently being evaluated for affordable, non-toxic, natural product-based therapies. In the present study, we have shown an environment-friendly and inexpensive method for carotenoid production from yeasts, utilizing "mandi" wastes, and investigated the biomedical properties of carotenoids, particularly antineoplastic properties. Methods: Vegetable "mandi" waste was used to prepare waste hydrolysate, a culture medium, in which oleaginous red yeast Rhodosporidium sp. was grown. Carotenoid pigments were extracted using the solvent extraction method and analyzed by UV spectroscopy, thin-layer chromatography (TLC), and high-performance liquid chromatography (HPLC). Antimicrobial, antioxidant, and anticancer activities of the extract were evaluated, followed by in silico docking and absorption, distribution, metabolism, and excretion/toxicity (ADME/T) studies. Results: Carotenoid extract was found to be composed of three main pigments-ß-carotene, torulene, and torularhodin. Extract exhibited significant antioxidant, antimicrobial, and anti-breast cancer activities in vitro while being biocompatible. Interestingly, carotenoids have shown better efficacy in triple-negative breast cancer (TNBC) cells than ER+PR+ cells. In silico evaluation predicted binding with breast cancer-specific molecular targets, specifically the three components showed good binding energy toward VEGF receptors and good drug likeliness properties, as well as less toxicity. Discussion: This is the first report on anti-breast cancer activities, particularly targeting TNBC cells by red yeast carotenoids (ß-carotene, torulene, and torularhodin) produced via a sustainable environment-friendly bioprocess utilizing waste hydrolysate.

6.
Life Sci ; 284: 119927, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34492262

RESUMO

AIMS: Among polyphenolic phytoconstituents with anticancer properties, Ellagic acid (EA) is widely reported for its translational potential in vitro but efficient in vivo delivery of EA has been a challenge. We, for the first time, used a tween 80 coated nano delivery of Ellagic acid to evaluate its preclinical efficacy in vitro and in vivo for breast cancer. MAIN METHODS: To overcome the challenges of in vivo delivery, two batches of chitosan-based nanoformulations of EA (with and without tween 80 coating) were prepared by the ionotropic gelation method. The nanoformulations were characterized and further evaluated in vitro against breast cancer cells (MCF7) and in vivo with EAC tumor-bearing mice for establishing their anticancer efficacy compared to Ellagic acid alone. A quantitative simulation study was undertaken to understand if the observed antitumor efficacy is due to the synergistic efficacy of the Chitosan-Ellagic acid combination. KEY FINDINGS: Results revealed that nanoformulations consist of good nano-sized encapsulation of EA and showed good drug entrapment-release capacity. Nano-encapsulated EA is biocompatible and exhibited higher cytotoxicity in vitro compared to EA alone. Similarly, significantly higher tumor regression was observed in nano-EA treated mice compared to EA alone, and best efficacy was observed with the nanoformulation with tween 80 coating. Furthermore, nanoformulations showed higher apoptosis in tumor tissues with no significant tissue toxicity in vital organs. SIGNIFICANCE: We report synergism of Chitosan-Ellagic acid combination in the tween 80 coated nanoparticles of Ellagic acid resulting in enhanced anti-breast tumor efficacy that may be of translational value for other tumor types, too.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Quitosana/química , Ácido Elágico/uso terapêutico , Nanopartículas/química , Polissorbatos/química , Animais , Neoplasias da Mama/patologia , Varredura Diferencial de Calorimetria , Morte Celular , Sobrevivência Celular , Simulação por Computador , Liberação Controlada de Fármacos , Ácido Elágico/farmacologia , Feminino , Células HEK293 , Humanos , Células MCF-7 , Camundongos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Eletricidade Estática , Carga Tumoral
7.
J Biol Chem ; 294(17): 6733-6750, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30824542

RESUMO

Notch signaling is reported to be deregulated in several malignancies, including breast, and the enzyme γ-secretase plays an important role in the activation and nuclear translocation of Notch intracellular domain (NICD). Hence, pharmacological inhibition of γ-secretase might lead to the subsequent inhibition of Notch signaling in cancer cells. In search of novel γ-secretase inhibitors (GSIs), we screened a series of triazole-based compounds for their potential to bind γ-secretase and observed that 3-(3'4',5'-trimethoxyphenyl)-5-(N-methyl-3'-indolyl)-1,2,4-triazole compound (also known as NMK-T-057) can bind to γ-secretase complex. Very interestingly, NMK-T-057 was found to inhibit proliferation, colony-forming ability, and motility in various breast cancer (BC) cells such as MDA-MB-231, MDA-MB-468, 4T1 (triple-negative cells), and MCF-7 (estrogen receptor (ER)/progesterone receptor (PR)-positive cell line) with negligible cytotoxicity against noncancerous cells (MCF-10A and peripheral blood mononuclear cells). Furthermore, significant induction of apoptosis and inhibition of epithelial-to-mesenchymal transition (EMT) and stemness were also observed in NMK-T-057-treated BC cells. The in silico study revealing the affinity of NMK-T-057 toward γ-secretase was further validated by a fluorescence-based γ-secretase activity assay, which confirmed inhibition of γ-secretase activity in NMK-T-057-treated BC cells. Interestingly, it was observed that NMK-T-057 induced significant autophagic responses in BC cells, which led to apoptosis. Moreover, NMK-T-057 was found to inhibit tumor progression in a 4T1-BALB/c mouse model. Hence, it may be concluded that NMK-T-057 could be a potential drug candidate against BC that can trigger autophagy-mediated cell death by inhibiting γ-secretase-mediated activation of Notch signaling.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Autofagia/efeitos dos fármacos , Neoplasias da Mama/patologia , Receptores Notch/metabolismo , Transdução de Sinais , Triazóis/farmacologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/enzimologia , Neoplasias da Mama/metabolismo , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Bioorg Med Chem ; 27(4): 604-619, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30638966

RESUMO

5-Lipoxygenase (5-LOX) is a key enzyme involved in the biosynthesis of pro-inflammatory leukotrienes, leading to asthma. Developing potent 5-LOX inhibitors especially, natural product based ones, are highly attractive. Coumaperine, a natural product found in white pepper and its derivatives were herein developed as 5-LOX inhibitors. We have synthesized twenty four derivatives, characterized and evaluated their 5-LOX inhibition potential. Coumaperine derivatives substituted with multiple hydroxy and multiple methoxy groups exhibited best 5-LOX inhibition. CP-209, a catechol type dihydroxyl derivative and CP-262-F2, a vicinal trihydroxyl derivative exhibited, 82.7% and 82.5% inhibition of 5-LOX respectively at 20 µM. Their IC50 values are 2.1 ±â€¯0.2 µM and 2.3 ±â€¯0.2 µM respectively, and are comparable to zileuton, IC50 = 1.4 ±â€¯0.2 µM. CP-155, a methylenedioxy derivative (a natural product) and CP-194, a 2,4,6-trimethoxy derivative showed 76.0% and 77.1% inhibition of 5-LOX respectively at 20 µM. Antioxidant study revealed that CP-209 and 262-F2 (at 20 µM) scavenged DPPH radical by 76.8% and 71.3% respectively. On the other hand, CP-155 and 194 showed very poor DPPH radical scavenging activity. Pseudo peroxidase assay confirmed that the mode of action of CP-209 and 262-F2 were by redox process, similar to zileuton, affecting the oxidation state of the metal ion in the enzyme. On the contrary, CP-155 and 194 probably act through some other mechanism which does not involve the disruption of the oxidation state of the metal in the enzyme. Molecular docking of CP-155 and 194 to the active site of 5-LOX and binding energy calculation suggested that they are non-competitive inhibitors. The In-Silico ADME/TOX analysis shows the active compounds (CP-155, 194, 209 and 262-F2) are with good drug likeliness and reduced toxicity compared to existing drug. These studies indicate that there is a great potential for coumaperine derivatives to be developed as anti-inflammatory drug.


Assuntos
Antioxidantes/farmacologia , Araquidonato 5-Lipoxigenase/metabolismo , Inibidores de Lipoxigenase/farmacologia , Piperidinas/farmacologia , Antioxidantes/síntese química , Antioxidantes/farmacocinética , Araquidonato 5-Lipoxigenase/química , Domínio Catalítico , Desenho de Fármacos , Ensaios Enzimáticos , Humanos , Hidroxiureia/análogos & derivados , Hidroxiureia/farmacologia , Inibidores de Lipoxigenase/síntese química , Inibidores de Lipoxigenase/farmacocinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Peroxidases/química , Piperidinas/síntese química , Piperidinas/farmacocinética , Relação Estrutura-Atividade
9.
Nanomedicine ; 15(1): 47-57, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30213518

RESUMO

Little is known about insulin's wound healing capability in normal as well as diabetic conditions. We here report specific interaction of silver nanoparticles (AgNPs) with insulin by making a ~2 nm thick coat around the AgNPs and its potent wound healing efficacy. Characterization of the interaction of human insulin with silver nanoparticles showed confirmed alteration of amide-I in insulin whereas amide-II and III remained unaltered. Further, nanoparticles protein interaction kinetics showed spontaneous interaction at physiological temperature with ΔG, ΔS, Ea and Ka values -7.48, 0.076, 3.84 kcal mol-1 and 6 × 105 s-1 respectively. Insulin loaded AgNPs (IAgNPs) showed significant improvement in healing activity in vitro (HEKa cells) and in vivo (Wister Rats) in comparison with the control in both normal and diabetic conditions. The underlying mechanism was attributed to a regulation of the balance between pro (IL-6, TNFα) and anti-inflammatory cytokines (IL-10) at the wound site to promote faster wound remodeling.


Assuntos
Citocinas/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Nanopartículas Metálicas/administração & dosagem , Cicatrização , Animais , Movimento Celular , Diabetes Mellitus Experimental/metabolismo , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Mediadores da Inflamação/metabolismo , Insulina/administração & dosagem , Insulina/química , Masculino , Nanopartículas Metálicas/química , Ratos , Ratos Wistar , Prata/química
10.
PLoS One ; 6(9): e25215, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21949884

RESUMO

Cutaneous wound healing is a normal physiological process and comprises different phases. Among these phases, angiogenesis or new blood vessel formation in wound tissue plays an important role. Skin is richly supplied by sympathetic nerves and evidences indicate the significant role of the sympathetic nervous system in cutaneous wound healing. Dopamine (DA) is an important catecholamine neurotransmitter released by the sympathetic nerve endings and recent studies have demonstrated the potent anti-angiogenic action of DA, which is mediated through its D(2) DA receptors. We therefore postulate that this endogenous catecholamine neurotransmitter may have a role in the neovascularization of dermal wound tissues and subsequently in the process of wound healing. In the present study, the therapeutic efficacy of D(2) DA receptor antagonist has been investigated for faster wound healing in a murine model of full thickness dermal wound. Our results indicate that treatment with specific D(2) DA receptor antagonist significantly expedites the process of full thickness normal dermal wound healing in mice by inducing angiogenesis in wound tissues. The underlined mechanisms have been attributed to the up-regulation of homeobox transcription factor HoxD3 and its target α5ß1 integrin, which play a pivotal role in wound angiogenesis. Since D(2) DA receptor antagonists are already in clinical use for other disorders, these results have significant translational value from the bench to the bedside for efficient wound management along with other conventional treatment modalities.


Assuntos
Derme/irrigação sanguínea , Derme/lesões , Dopamina/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/fisiologia , Cicatrização/fisiologia , Ferimentos e Lesões/prevenção & controle , Animais , Western Blotting , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Derme/efeitos dos fármacos , Dopaminérgicos/farmacologia , Antagonistas de Dopamina/farmacologia , Antagonistas dos Receptores de Dopamina D2 , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Citometria de Fluxo , Integrina alfa5beta1/metabolismo , Camundongos , Receptores de Dopamina D2/metabolismo , Salicilamidas/farmacologia , Veias Umbilicais/citologia , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo , Ferimentos e Lesões/patologia
11.
Am J Pathol ; 177(6): 2701-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21075859

RESUMO

The overexpression of insulin-like growth factor receptor-I (IGF-IR) and the activation of its signaling pathways both play critical roles in the development and progression of gastric cancer. Dopamine (DA), a major enteric neurotransmitter, has been reported to have a wide variety of physiological functions in the gastrointestinal tract, including the stomach. We have previously reported that both DA and tyrosine hydroxylase, the rate-limiting enzyme required for the synthesis of DA, are lost in malignant gastric tissues. The effect of this loss of DA on IGF-IR-induced growth of gastric cancer has not yet been elucidated; we therefore investigated the role of DA, if any, on IGF-IR-induced proliferation of malignant gastric cells. There was a significant increase in the expression of phosphorylated IGF-IR and its downstream signaling molecule AKT in human malignant gastric tissues compared with normal nonmalignant tissues. Furthermore, to determine whether this loss of DA has any effect on the activation of IGF-IR signaling pathways in malignant gastric tumors, in vitro experiments were undertaken, using AGS gastric cancer cells. Our results demonstrated that DA acting through its D(2) receptor, inhibits IGF-I-induced proliferation of AGS cells by up-regulating KLF4, a negative regulator of the cell cycle through down regulation of IGF-IR and AKT phosphorylation. Our results suggest that DA is an important regulator of IGF-IR function in malignant gastric cancer cells.


Assuntos
Adenocarcinoma/patologia , Proliferação de Células/efeitos dos fármacos , Dopamina/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Fatores de Transcrição Kruppel-Like/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo , Receptores de Dopamina D2/fisiologia , Neoplasias Gástricas/patologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Idoso , Células Cultivadas , Dopamina/metabolismo , Regulação para Baixo/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Fator de Crescimento Insulin-Like I/efeitos adversos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Masculino , Pessoa de Meia-Idade , Fosforilação/efeitos dos fármacos , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/fisiologia , Receptores de Dopamina D2/agonistas , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Regulação para Cima/efeitos dos fármacos
12.
J Biol Chem ; 285(35): 27026-27032, 2010 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-20592018

RESUMO

Dopamine is a catecholamine neurotransmitter, which plays an important role in the regulation of T cell functions. In activated T cells from normal volunteers, stimulation of D(1) and D(2) dopamine receptors inhibit cell proliferation and cytokine secretion. However, there is no report yet regarding the regulatory role of D(1) and D(2) dopamine receptors in abnormally proliferating T cells. The present study investigates the expression and effect of activation of these dopamine receptors in Jurkat cells, a leukemic T cell line showing uncontrolled proliferation. Like normal human T cells, in Jurkat cells, D(1) and D(2) dopamine receptors are also expressed; however, unlike activated normal T cells, stimulation of these dopamine receptors in Jurkat cells fails to inhibit their T cell receptor-induced proliferation. This alteration is due to failure of D(1) dopamine receptor-mediated activation of cyclic AMP signaling and a missense mutation at the third cytoplasmic loop of D(2) dopamine receptors affecting inhibition of phosphorylation of ZAP-70, an important downstream protein transducing signal from the T cell receptor. These results help to understand the biology of abnormal proliferation of T cells in pathophysiological conditions where dopamine plays an important role.


Assuntos
Proliferação de Células/efeitos dos fármacos , Dopaminérgicos/farmacologia , Dopamina/farmacologia , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linfócitos T/metabolismo , Citocinas/metabolismo , Dopamina/metabolismo , Dopaminérgicos/metabolismo , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Células Jurkat , Ativação Linfocitária/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Receptores de Dopamina D1/genética , Receptores de Dopamina D2/genética , Proteína-Tirosina Quinase ZAP-70/genética , Proteína-Tirosina Quinase ZAP-70/metabolismo
13.
Brain Behav Immun ; 24(4): 525-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19896530

RESUMO

The neurotransmitter dopamine (DA) is an important molecule bridging the nervous and immune systems. DA through autocrine/paracrine manner modulates the functions of immune effector cells by acting through its receptors present in these cells. DA also has unique and opposite effects on T cell functions. Although DA activates naïve or resting T cells, but it inhibits activated T cells. In addition, changes in the expression of DA receptors and their signaling pathways especially in T cells are associated with altered immune functions in disorders like schizophrenia and Parkinson's disease. These results suggest an immunoregulatory role of DA. Therefore, targeting DA receptors and their signaling pathways in these cells by using DA receptor agonists and antagonists may be useful for the treatment of diseases where DA induced altered immunity play a pathogenic role.


Assuntos
Dopamina/imunologia , Receptores Dopaminérgicos/imunologia , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Dopamina/metabolismo , Agonistas de Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/imunologia , Psiconeuroimunologia , Esquizofrenia/tratamento farmacológico , Esquizofrenia/imunologia , Transdução de Sinais/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos
14.
Cancer Res ; 69(9): 3727-30, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19383906

RESUMO

Among the regulators of angiogenesis, catecholamine neurotransmitters are of recent interest because of their opposite roles in the regulation of tumor neovascularization. Norepinephrine and epinephrine by acting through specific adrenoceptors increase the synthesis of proangiogenic factors, and thereby, promote tumor growth. In contrast, dopamine acting via its specific D(2) receptors inhibits tumor growth by suppressing the actions of vascular permeability factor/vascular endothelial growth factor-A on both tumor endothelial and bone marrow-derived endothelial progenitor cells. These reports identify novel endogenous regulators of tumor angiogenesis and also indicate a new and an inexpensive class of antiangiogenic drugs for the treatment of cancer.


Assuntos
Proteínas Angiogênicas/metabolismo , Catecolaminas/metabolismo , Neoplasias/irrigação sanguínea , Neoplasias/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Proteínas Angiogênicas/antagonistas & inibidores , Proteínas Angiogênicas/biossíntese , Animais , Humanos , Neoplasias/metabolismo , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia
15.
J Immunol ; 177(11): 7525-9, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17114421

RESUMO

The neurotransmitter dopamine (DA) is an important regulator of human T cell functions. Although it has been observed that DA, by acting through the D1/D5, D2, and D3 receptors, can activate resting T cells by stimulating the release of cytokines and the expression of surface integrins and also inhibit the proliferation of activated T cells by down-regulating nonreceptor tyrosine kinases, there is not yet a report indicating the functional significance of the D4 DA receptors present in these cells. The present work, for the first time, demonstrates that the stimulation of D4 DA receptors in human T cells induces T cell quiescence by up-regulating lung Krüppel-like factor-2 expression through the inhibition of ERK1/ERK2 phosphorylation. These results reveal a new link between the nervous system and T cell quiescence and indicate that D4 DA receptor agonists may have a therapeutic value in diseases with uncontrolled T cell proliferation.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fatores de Transcrição Kruppel-Like/biossíntese , Ativação Linfocitária/imunologia , Receptores de Dopamina D4/imunologia , Linfócitos T/imunologia , Proliferação de Células/efeitos dos fármacos , Dopamina/imunologia , Dopamina/metabolismo , Agonistas de Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/imunologia , Citometria de Fluxo , Expressão Gênica , Regulação da Expressão Gênica , Humanos , Immunoblotting , Fatores de Transcrição Kruppel-Like/imunologia , Ativação Linfocitária/efeitos dos fármacos , Fosforilação , Receptores de Dopamina D4/efeitos dos fármacos , Receptores de Dopamina D4/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Regulação para Cima
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA