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1.
Braz J Biol ; 82: e262815, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35976285

RESUMO

The objective of the study was to evaluate the quality of Zamzam water, holy water for Muslims and consumed for its medicinal value. The present study demonstrates the physicochemical characterization and wound healing property of Zamzam water. The physicochemical characterization of Zamzam water samples was analyzed for dissolved oxygen, pH, conductivity, total dissolved solids, redox potential, zeta potential, polydispersity index, and zeta size. The microbial quality of Zamzam water was also assessed by exposing water samples to open air. In this work, Zamzam water was also screened for the medicinal value through wound healing properties in Wistar rats. Zamzam water exhibited a unique physicochemical characterization with high levels of dissolved oxygen, zeta potential, polydispersity index, redox potential, total dissolved solids, and conductivity before exposure to open air. After open air exposure, Zamzam water resisted the growth of bacteria. The wound healing properties of Zamzam water in vivo showed a 96% of healing effect on 12th day observation. The wound healing was achieved by modulating pro-inflammatory cytokine such as interleukin -1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor -α (TNF-α). Followed by the level of apoptosis markers caspase-9 and caspase-3 were reduced. The present study proved that Zamzam water is a good-quality water and showed excellent wound healing property. Therefore, Zamzam water can be used for pharmaceutical formulations.


Assuntos
Água , Cicatrização , Animais , Oxigênio , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa
2.
Braz J Biol ; 82: e256158, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35384962

RESUMO

The study investigated the wound healing effect of medicinal oil (MO) formulation prepared from Murraya koenigii leaves extract (methanolic) incorporated in olive oil. The MO was visually transparent, homogenous, smooth in texture, the viscosity grade was observed as 140 cP and easily spreadable. Pro-inflammatory cytokines IL-1ß, IL-6, and TNF-α were significantly reduced to 82.3 ± 3.5, 156 ± 6.2, 137.3. ± 5.5 pg/ml, respectively after treatment with MO when compared to disease control animals that showed IL-1ß, IL-6, and TNF-α levels of 170 ± 6, 265 ± 7, and 288.6 ± 11, pg/ml respectively. The level of pro-inflammatory cytokine in povidone iodine solution (PIS) group was 95.3 ± 3, 162 ± 6, 177.6 ± 8.9 pg/ml of IL-1ß, IL-6, and TNF-α respectively. Interestingly, the wound-healing efficacy of MO was found better as compared to povidone iodine treated standard group and concluded that MO has excellent wound healing effect.


Assuntos
Murraya , Animais , Citocinas , Interleucina-6/farmacologia , Azeite de Oliva/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta , Povidona-Iodo/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Cicatrização
3.
Braz. j. biol ; 82: e256158, 2022. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364495

RESUMO

The study investigated the wound healing effect of medicinal oil (MO) formulation prepared from Murraya koenigii leaves extract (methanolic) incorporated in olive oil. The MO was visually transparent, homogenous, smooth in texture, the viscosity grade was observed as 140 cP and easily spreadable. Pro-inflammatory cytokines IL-1ß, IL-6, and TNF-α were significantly reduced to 82.3 ± 3.5, 156 ± 6.2, 137.3. ± 5.5 pg/ml, respectively after treatment with MO when compared to disease control animals that showed IL-1ß, IL-6, and TNF-α levels of 170 ± 6, 265 ± 7, and 288.6 ± 11, pg/ml respectively. The level of pro-inflammatory cytokine in povidone iodine solution (PIS) group was 95.3 ± 3, 162 ± 6, 177.6 ± 8.9 pg/ml of IL-1ß, IL-6, and TNF-α respectively. Interestingly, the wound-healing efficacy of MO was found better as compared to povidone iodine treated standard group and concluded that MO has excellent wound healing effect.


O estudo investigou o efeito cicatrizante da formulação de óleo medicinal (MO) preparado a partir do extrato de folhas de Murraya koenigii (metanol) incorporado ao azeite de oliva. O MO era visualmente transparente, homogêneo, de textura lisa, o grau de viscosidade observado foi de 140 cP e facilmente espalhável. As citocinas pró-inflamatórias IL-1ß, IL-6 e TNF-α foram significativamente reduzidas para 82,3 ± 3,5, 156 ± 6,2, 137,3. ± 5,5 pg/ml, respectivamente, após o tratamento com MO quando comparados aos animais controle da doença que apresentaram níveis de IL-1ß, IL-6 e TNF-α de 170 ± 6, 265 ± 7 e 288,6 ± 11, pg/ml, respectivamente . O nível de citocina pró-inflamatória no grupo solução de iodopovidona (PIS) foi de 95,3 ± 3, 162 ± 6, 177,6 ± 8,9 pg/ml de IL-1ß, IL-6 e TNF-α, respectivamente. Curiosamente, a eficácia de cicatrização de feridas de MO foi encontrada melhor em comparação com o grupo padrão tratado com iodopovidona e concluiu que a preparação de MO tem efeito de cicatrização de feridas.


Assuntos
Cicatrização , Ferimentos e Lesões , Citocinas , Metanol , Azeite de Oliva
4.
J Pharm Bioallied Sci ; 4(Suppl 1): S74-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23066214

RESUMO

Spray formulation can minimize pain and irritation experience during the application of conventional dosage forms. Econazole Nitrate is an active ingredient of the aerosol concentrate to be used for twice-daily application because of its long durability in the superficial layers of the fungal infected skin. The aim of this study is preliminary investigation of Econazole Nitrate spray by varying the concentrations of different constituents of the spray. The ratios of Propylene glycol (PG) and isopropyl myristate (IPM) were selected as independent variables in 2(2) full factorial designs, keeping the concentration of solvent, co-solvent and propellant LPG constant. Aerosol also contained Ethanol as solvent and Isopropyl alcohol as co-solvent. All ingredients of the aerosol were packaged in an aluminum container fitted with continuous-spray valves. Physical properties evaluated for the Econazole Nitrate spray included delivery rate, delivery amount, pressure, minimum fill, leakage, flammability, spray patterns, particle image and plume angle. Glass containers were used to study incompatibility between concentrate and propellant due to the ease of visible inspection. Isopropyl myristate at lower concentrate showed turbidity, while at high concentration it met the requirements for aerosol and produced Econazole Nitrate spray with expected characteristics.

5.
J Adv Pharm Technol Res ; 2(1): 56-61, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22171294

RESUMO

In ethno medicinal practices, the traditional healers use the genus Curcuma for the treatment of various ailments but Curcuma caesia Roxb. is a very less known and almost untouched drug. The present work attempts to establish the necessary pharmocognostic standards for evaluating the plant material of C. caesia Roxb. Various parameters, such as morphology, microscopy, physicochemical constants, and phytochemical profiles of the entire parts of the plant were studied and the salient diagnostic features are documented. Major chemical constituents, extractive values, physicochemical constants, and other features are also been recorded.

6.
Oncogene ; 29(33): 4648-57, 2010 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-20531297

RESUMO

Endocrine therapy is the main therapeutic option for patients with estrogen receptor (ERalpha)-positive breast cancer. Resistance to this treatment is often associated with estrogen-independent activation of ERalpha. In this study, we show that in ERalpha-positive breast cancer cells, activation of the receptor tyrosine kinase RET (REarranged during Transfection) by its ligand GDNF results in increased ERalpha phosphorylation on Ser118 and Ser167 and estrogen-independent activation of ERalpha transcriptional activity. Further, we identify mTOR as a key component in this downstream signaling pathway. In tamoxifen response experiments, RET downregulation resulted in 6.2-fold increase in sensitivity of MCF7 cells to antiproliferative effects of tamoxifen, whereas GDNF stimulation had a protective effect against the drug. In tamoxifen-resistant (TAM(R)-1) MCF7 cells, targeting RET restored tamoxifen sensitivity. Finally, examination of two independent tissue microarrays of primary human breast cancers revealed that expression of RET protein was significantly associated with ERalpha-positive tumors and that in primary tumors from patients who subsequently developed invasive recurrence after adjuvant tamoxifen treatment, there was a twofold increase in the number of RET-positive tumors. Together these findings identify RET as a potentially important therapeutic target in ERalpha-positive breast cancers and in particular in tamoxifen-resistant tumors.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Proteínas Proto-Oncogênicas c-ret/metabolismo , Tamoxifeno/farmacologia , Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-ret/genética , Transdução de Sinais , Serina-Treonina Quinases TOR , Tamoxifeno/análogos & derivados
7.
Br J Cancer ; 102(8): 1235-43, 2010 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-20386540

RESUMO

BACKGROUND: Cross-talk between receptor tyrosine kinases and the oestrogen receptor (ER) is implicated in resistance to endocrine therapy. We investigated whether AEE788 (a combined inhibitor of EGFR, HER2 and VEGFR) plus tamoxifen or letrozole enhanced the individual anti-tumour effects of these agents. METHODS: Breast cancer cell lines modelling endocrine-resistant and -sensitive disease were engineered to express aromatase (A) and examined using proliferation, western blotting and ER-alpha transcription assays. RESULTS: AEE788 enhanced the anti-proliferative effect of tamoxifen and letrozole in ER(+) cell lines (MCF-7 2A, ZR75.1 A3 and BT474 A3). This associated with an elevated G1 arrest and nuclear accumulation of p27. It is noteworthy that AEE788 alone or in combination with endocrine therapy increased the expression of progesterone receptor (PGR) and TFF1 in BT474 A3 cells. This may indicate a mechanism of resistance to AEE788 in ER(+)/HER2(+) breast cancers. In a ZR75.1 A3 xenograft, AEE788 alone or in combination with tamoxifen provided no further benefit compared with letrozole. However, letrozole plus AEE788 produced a significantly greater inhibition of tumour growth compared with letrozole alone. CONCLUSION: These data suggest that AEE788 plus letrozole in breast cancer overexpressing HER2 may provide superior anti-tumour activity, compared with single agents.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Receptores ErbB/antagonistas & inibidores , Nitrilas/administração & dosagem , Purinas/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Receptores de Estrogênio/metabolismo , Tamoxifeno/administração & dosagem , Triazóis/administração & dosagem , Animais , Aromatase/genética , Aromatase/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Citoproteção/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Humanos , Letrozol , Camundongos , Camundongos Nus , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Purinas/administração & dosagem , Transcrição Gênica/efeitos dos fármacos , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Endocr Relat Cancer ; 12(4): 1017-36, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16322340

RESUMO

Long-term culture of MCF-7 wild-type (wt) cells in steroid-depleted medium (LTED) results in hypersensitivity to oestradiol (E2) coinciding with elevated levels of ERalpha and enhanced growth factor signalling. In this study, we aimed to compare the effects of the pure anti-oestrogen ICI 182,780 (ICI) with the competitive anti-oestrogen tamoxifen (TAM) on oestrogen and IGF signalling in these cells. Wt MCF-7 and LTED cells were treated with a log 7 concentration range of E2, TAM or ICI. Effects on cell growth, ERalpha transactivation, expression of ERalpha, ERbeta and components of the IGF pathway were measured with and without insulin. In the presence of insulin, growth of LTED cells was refractory to TAM but inhibited by ICI and E2. In the absence of insulin, LTED cells showed persistent hypersensitivity to E2, and remained inhibited by ICI but were largely unaffected by TAM. ICI but not TAM inhibited ER-mediated gene transcription and treatment with ICI resulted in a dose-dependent reduction in ERalpha levels whilst having no effect on ERbeta expression. IGF-I receptor and insulin receptor substrate 2 levels were increased in LTED versus the Wt MCF-7 cells, and ICI but not TAM reduced their expression in a dose-dependent fashion. Thus IGF signalling as well as ERalpha expression and function are enhanced during LTED. While the resultant cells are resistant to TAM, ICI down-regulates ERalpha, reducing IGF signalling and cell growth. These results support the use of ICI in women with ER-positive breast cancer who have relapsed on an aromatase inhibitor.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Estradiol/análogos & derivados , Antagonistas de Estrogênios/uso terapêutico , Receptor alfa de Estrogênio/antagonistas & inibidores , Antagonistas da Insulina/uso terapêutico , Antineoplásicos Hormonais/farmacologia , Apoptose , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Estradiol/farmacologia , Estradiol/uso terapêutico , Antagonistas de Estrogênios/farmacologia , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Estrogênios/deficiência , Feminino , Fulvestranto , Humanos , Insulina/farmacologia , Antagonistas da Insulina/farmacologia , Proteínas Substratos do Receptor de Insulina , Peptídeos e Proteínas de Sinalização Intracelular , Fosfoproteínas/efeitos dos fármacos , Fosfoproteínas/metabolismo , Receptor IGF Tipo 1/efeitos dos fármacos , Receptor IGF Tipo 1/metabolismo , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico , Transcrição Gênica/efeitos dos fármacos
9.
Pharmazie ; 60(2): 131-4, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15739902

RESUMO

Microspheres of chitosan hydrochloride (CH) were prepared in order to deliver albendazole specifically into the colon. Microspheres were prepared by an emulsion method using different ratios of drug and CH (1:1 to 1:5), agitation speeds (500 to 1500 rpm) and concentrations of glutaraldehyde in toluene as the cross-linking agent (0.25 to 1.0% w/v). The effect of polymer concentration, stirring rate and concentration of cross-linking agent on the particle size and drug loading was studied. With an increase in CH concentration, the average particle size was increased. Increased agitation speed reduced the size of the microspheres but higher agitation speed resulted in irregularly shaped microspheres. Increasing the concentration of cross-linking agent produced more regularly shaped microspheres of smaller size. The drug loading was highest at a drug: CH ratio of 1:3, stirring speed 1000 rpm and 0.75% w/v concentration of cross-linking agent. The effect of CH concentration on in vitro drug release from the microspheres was evaluated in simulated g.i.t fluids. A comparative in vitro drug release study of the optimized formulation was carried out in simulated colonic fluid, with and without 2% rat caecal content. The drug release in 24 h was 48.9% in colonic fluid without rat caecal content, and 76.5% in colonic fluid with rat caecal contents.


Assuntos
Albendazol/administração & dosagem , Anti-Helmínticos/administração & dosagem , Colo/metabolismo , Sistemas de Liberação de Medicamentos , Animais , Ceco/metabolismo , Quitosana , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Excipientes , Íleo/metabolismo , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Microesferas , Tamanho da Partícula , Ratos , Espectrofotometria Infravermelho
10.
Drug Deliv ; 11(3): 193-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15204638

RESUMO

Aquasomes, a new drug delivery system comprised of surface-modified nanocrystalline ceramic carbohydrate composites, was developed to serve as haemoglobin carrier for oxygen delivery. The hydroxy-apatite ceramic core was prepared by coprecipitation and self-precipitation and coated with various sugars like cellobiose, maltose, sucrose, and trehalose. The effect of drying methods, i.e., air drying, vacuum drying, and lyophilization, on the degree of binding was studied by concanavalin-induced aggregation method. Haemoglobin was adsorbed over the sugar-coated ceramics, and percent loading was estimated by benzidine method. The adsorption of sugars on calcium hydro-apatite powder and haemoglobin adsorption on sugar-adsorbed ceramic followed both Freundlich and Langmuir isotherm. The haemoglobin aquasome formulations (equivalent to 7.5% Hb) were suspended in a phosphate buffer containing 7.5% w/v albumin and 0.01% w/v lecithin, and they were evaluated for oxygen-carrying capacity, which was found to be similar to fresh blood. The Hill coefficients were found to be fairly good for its use as oxygen carrier. The haemoglobin aquasome formulations did not induce haemolysis of red blood cells nor alter the blood coagulation time. The haemoglobin content of the formulation remained unchanged on storage for 30 days. The haemoglobin desorption was fairly low under shear conditions, indicating good stability of formulation in biological system. During in vivo study in rats the survivals were monitored as function of hematocrit in rats receiving isovolemic exchange transfusion. Arterial blood pressure and heart rate did not change significantly in animals transfused with aquasomal suspension on 50% exchange transfusion.


Assuntos
Cerâmica , Hemoglobinas/administração & dosagem , Veículos Farmacêuticos , Adsorção , Animais , Materiais Biocompatíveis , Transfusão de Sangue , Carboidratos , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Durapatita , Feminino , Hematócrito , Hemodinâmica/efeitos dos fármacos , Hemoglobinas/farmacologia , Hemólise/efeitos dos fármacos , Masculino , Microesferas , Oxigênio/química , Tamanho da Partícula , Porosidade , Pós , Ratos , Ratos Sprague-Dawley , Espectrofotometria Ultravioleta , Propriedades de Superfície , Viscosidade
11.
Pharmazie ; 59(3): 191-3, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15074590

RESUMO

The solubilization of piroxicam to increase transdermal permeation rate was attempted by incorporating the drug in reverse micelle systems consisting of lecithin/isopropyl myristate/water [RMS-1] and sodium bis(2-ethylhexyl) sulfosuccinate (AOT)/isooctane/water [RMS-2]. The change in polarity of water present in the water pool formed by reverse micelles resulted in a solubilization of piroxicam. These systems were used for the formation of reverse micellar organogels RMO-1 and RMO-2 by means of either varying hydration ratio (Wo) or by addition of a macromolecule, e.g. gelatin, into the system or by taking both the parameters in consideration. These systems were evaluated for physical properties, toxicology, in vitro and in vivo transdermal permeation. Significant (p < 0.01) inhibition of carrageenan induced rat paw oedema was observed for products RMO-1 and RMO-2 and a marketed transdermal product after 3 h.


Assuntos
Anti-Inflamatórios não Esteroides/química , Piroxicam/química , Administração Tópica , Animais , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/toxicidade , Química Farmacêutica , Géis , Micelas , Piroxicam/farmacocinética , Piroxicam/toxicidade , Coelhos , Ratos , Absorção Cutânea , Solventes , Tensoativos , Temperatura
12.
Int J Pharm ; 274(1-2): 149-55, 2004 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15072791

RESUMO

Nimesulide is a non-steroidal anti-inflammatory drug (NSAID) that exhibits analgesic, antipyretic and anti-inflammatory activities. It is practically insoluble in water. The effect of various hydrotropes such as nicotinamide, sodium ascorbate, sodium benzoate, sodium salicylate and piperazine on the solubility of nimesulide was investigated. The solubility enhancement of nimesulide by the hydrotropes was observed in decreasing order as piperazine > sodium ascorbate > sodium salicylate > sodium benzoate > nicotinamide. In order to elucidate the probable mechanism of solubilization, various solution properties of hydrotropes such as viscosity, specific gravity, surface tension, refractive index, specific conductance of hydrotropic solutions were studied at 25 +/- 2 degrees C on the basis of earlier studies. The hydrotropic solubilization of nimesulide at lower hydrotrope concentration may be attributed to weak ionic interactions while that at higher hydrotrope concentration may be due to molecular aggregation. Parenteral formulations using piperazine as a hydrotrope were developed and studied for physical and chemical stability.


Assuntos
Sulfonamidas/administração & dosagem , Sulfonamidas/química , Infusões Parenterais , Solubilidade/efeitos dos fármacos , Tensão Superficial/efeitos dos fármacos , Viscosidade/efeitos dos fármacos
13.
Phys Rev Lett ; 88(10): 102502, 2002 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-11909351

RESUMO

The quadrupole moment of the 11(-) isomer in 196Pb has been measured by the level mixing spectroscopy method. This state has a pi(3s(-2)(1/2)1h(9/2)1i(13/2))11(-) configuration which is involved in most of the shears band heads in the Pb region. The first directly measured value of Q(s)(11(-)) = (-)3.41(66) b, coupled to the previously known quadrupole moment of the nu(1i(-2)(13/2))12(+) isomer allows us to estimate the quadrupole moment of the 16(-) shears band head as Q(s)(16(-)) = -0.32(10) b. The experimental values are compared to tilted axis cranking calculations, giving insight into the validity of the additivity approach to couple quadrupole moments and on the amount of deformation in the shears bands.

15.
Cytokine ; 12(9): 1322-5, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10975990

RESUMO

Vascular smooth muscle cells (VSMC) may be programmed by nutrient deprivation. We found that after 2 and 12 h exposure to 75% reduced amino acids, the release of basic fibroblast growth factor (bFGF) and transforming growth factor beta1 (TGF beta 1) from VSMC was significantly greater than that from cells maintained in control medium [2572.0 (546.3) vs 602.1 (241.7), P=0.001 and 16 028.0 (2192. 4) vs 13 027.3 (1233.5) pg/10(6)cells, P=0.022 respectively]. These differences were magnified after two passages of exposure for both bFGF (P=0.0001) and TGF beta 1 (P=0.0001). The stimulated release of VEGF by hypoxia and bFGF was unaffected. Amino acid deprivation of human VSMC is associated with a patterned release of angiogenic cytokines which could be relevant to the programmed changes in VSMC phenotype.


Assuntos
Aminoácidos/farmacologia , Citocinas/biossíntese , Músculo Liso Vascular/metabolismo , Neovascularização Fisiológica , Células Cultivadas , Meios de Cultura/farmacologia , Endotélio Vascular/metabolismo , Fator 2 de Crescimento de Fibroblastos/biossíntese , Humanos , Hipóxia , Fenótipo , Fatores de Tempo , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta1 , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo
17.
J Cell Physiol ; 176(2): 359-64, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9648923

RESUMO

The role of nutrient supply in the replicative capacity and secretory phenotype of cultured human diploid cells is unclear. We examined the relationship between amino acid privation, the secretion of vascular endothelial growth factor (VEGF) and growth phenotype of vascular smooth muscle cells (VSMC), and endothelial cells. Cultures of VSMCs, but not endothelial cells, were growth inhibited by exposure to medium that was 75% deficient in leucine, methionine, arginine, and cysteine over two passages. Exposed VSMC cultures exhibited an increased vulnerability to apoptosis. The maximal cumulative population doubling of the exposed cells was reduced significantly compared with the control cells (25.7 +/- 2.0 doublings vs. 27.9 +/- 2.1 doublings; P < 0.03). Constitutive VEGF production first became evident in the later passages of the exposed and nonexposed cell cultures. However, production of VEGF was 17-fold greater in the exposed cultures at the tenth passage (P < 0.001). The replicative capacity and constitutive production of VEGF in VSMCs in culture may be programmed by transient privation of amino acids. These observations are relevant to new concepts concerning the pathogenesis of vascular disease.


Assuntos
Aminoácidos/farmacologia , Fatores de Crescimento Endotelial/biossíntese , Linfocinas/biossíntese , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Apoptose/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Veias Umbilicais/citologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
18.
Graefes Arch Clin Exp Ophthalmol ; 236(1): 1-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9457509

RESUMO

BACKGROUND: As growth factors play an important role in epithelial wound repair, we evaluated the effect of exogenous growth factors in the presence and absence of corneal epithelial and keratocyte conditioned medium on human corneal epithelial cell and keratocyte proliferation. METHODS: Preconfluent cultures of human corneal epithelial cells or stromal keratocytes were exposed to varying concentrations of EGF, TGF-beta or bFGF in the presence or absence of human corneal epithelial or stromal keratocyte conditioned medium. Cell numbers were determined after 48 h incubation. RIA and ELISA were used to quantify the levels of EGF, TGF-beta and bFGF in conditioned media. RESULTS: EGF and bFGF increased, while TGF-beta decreased, the proliferation of both cell types in a dose-dependent manner. Epithelial cell conditioned medium inhibited, and keratocyte conditioned medium stimulated, the proliferation of both cell types. The proliferative effects of EGF, TGF-beta and bFGF in the presence of keratocyte conditioned medium were additive for both cell types. By contrast, the addition of exogenous growth factors was unable to overcome the inhibitory potential of epithelial conditioned medium. Both conditioned media contained significant levels of bFGF, but TGF-beta levels in epithelial conditioned medium were up to 5 times greater than that in keratocyte conditioned medium. CONCLUSIONS: The results indicate that corneal cells maintain tissue homeostasis and modulate the wound healing response via paracrine/autocrine pathways.


Assuntos
Substância Própria/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Epitélio Corneano/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Comunicação Celular , Contagem de Células , Divisão Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Substância Própria/citologia , Substância Própria/metabolismo , Transplante de Córnea , Meios de Cultivo Condicionados/metabolismo , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Epitélio Corneano/citologia , Epitélio Corneano/metabolismo , Seguimentos , Humanos , Pessoa de Meia-Idade , Radioimunoensaio , Doadores de Tecidos
19.
Exp Eye Res ; 62(5): 555-64, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8759523

RESUMO

The effects of growth factors on re-epithelialization of wounded human and bovine corneas were studied in a simple organ culture system. Excisional trephine and epithelial scrape wounds were created on bovine and human corneo-scleral rings in which the endothelial corneal concavity was then filled with an agar-collagen mixture. Organ culture was undertaken at 37 degrees C in a humidified 5% CO2 incubator with serum-free Medium 199 maintained at the level of the conjunctival epithelium. Rates of reepithelialization in response to addition of exogenous epidermal growth factor (EGF), basic fibroblast growth factor (bFGF) and transforming growth factor type beta 1 (TGF-beta 1) were assessed by image analysis. Corneal cultures could be maintained for up to 3 weeks without significant stromal oedema or keratocyte deterioration and with little loss of epithelial architecture. Following wounding the cornea reepithelialized in a similar fashion to that observed in vivo i.e. a lag phase followed by migration/proliferation and the reformation of an intact multilayered epithelium. EGF accelerated, basic FGF had no effect on, and TGF-beta 1 inhibited the rate of corneal re-epithelialization. Our organ culture model maintains corneal integrity and provides a practical system in which to study factors that modulate corneal reepithelialization following wounding.


Assuntos
Lesões da Córnea , Substâncias de Crescimento/farmacologia , Técnicas de Cultura de Órgãos , Cicatrização/efeitos dos fármacos , Animais , Bovinos , Divisão Celular , Córnea/citologia , Relação Dose-Resposta a Droga , Fator de Crescimento Epidérmico/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Fatores de Tempo , Fator de Crescimento Transformador beta/farmacologia
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