RESUMO
We investigated the effects of gossypol acetic acid (GAA) on the proliferation, apoptosis, and expression of DNA methyltransferase 1 (DNMT1) mRNA in human adenoid cystic carcinoma (ACC-M) cells in vitro. The proliferation and apoptosis of ACC-M cells after treatment with different concentrations of GAA were detected using Cell Counting Kit-8 and flow cytometry, respectively. DNMT1 mRNA expression was measured by real-time fluorescence quantitative polymerase chain reaction. The growth of ACC-M cells was inhibited after treatment with GAA for 24, 48, and 72 h. The apoptotic rates of ACC-M cells after treatment with GAA for 72 h were higher than those of control cells (without treatment) (P < 0.05). DNMT1 mRNA expression in ACC-M after treatment with GAA for 72 h was lower than that in control cells (P < 0.05). GAA had inhibitory effects on the proliferation and induced apoptosis of human ACC-M cells, while GAA also reduced the expression level of DNMT1 mRNA in ACC-M cells.
Assuntos
Carcinoma Adenoide Cístico/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Gossipol/análogos & derivados , Apoptose/efeitos dos fármacos , Carcinoma Adenoide Cístico/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/genética , Citometria de Fluxo , Gossipol/farmacologia , HumanosRESUMO
BACKGROUND: Gossypol is a chemical present in the seeds of cotton plants (Gossypium sp.) that reduces fertility in farm animals. Vitamin E is an antioxidant and may help to protect cells and tissues against the deleterious effects of free radicals. The aim of this study was to evaluate the mechanisms of reproductive toxicity of gossypol in rats and the protective effects of vitamin E. Forty Wistar rats were used, divided into four experimental groups (n = 10): DMSO/saline + corn oil; DMSO/saline + vitamin E; gossypol + corn oil; and gossypol + vitamin E. RESULTS: Fertility was significantly reduced in male rats treated with gossypol in that a significant decrease in epididymal sperm count was observed (P < 0.05) and the number of offspring was significantly reduced in females mated with them (P < 0.05). This dysfunction was prevented by vitamin E. Gossypol caused a significant increase in the activity of the enzymes glutathione peroxidase (P < 0.01) and glutathione reductase (P < 0.01), but vitamin E did not reduce the enzyme activities (P > 0.05). The levels of reduced glutathione and pyridine nucleotides in testis homogenate were significantly reduced by gossypol (P < 0.05 and P < 0.01, respectively) and this reduction was accompanied by increased levels of oxidized glutathione (P < 0.05). Vitamin E showed a preventive effect on the changes in the levels of these substances. Gossypol significantly increased the levels of malondialdehyde (P < 0.01), a lipid peroxidation indicator, whereas treatment with vitamin E inhibited the action of the gossypol. Vitamin E prevented a decrease in mitochondrial ATP induced by gossypol (P < 0.05). CONCLUSIONS: This study suggests that the reproductive dysfunction caused by gossypol may be related to oxidative stress and mitochondrial bioenergetic damage and that treatment with vitamin E can prevent the infertility caused by the toxin.
Assuntos
Anticoncepcionais Masculinos/farmacologia , Fertilidade/efeitos dos fármacos , Gossipol/farmacologia , Vitamina E/farmacologia , Animais , Feminino , Glutationa Peroxidase , Glutationa Redutase , Gossipol/efeitos adversos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído , Estresse Oxidativo/efeitos dos fármacos , Gravidez , Ratos , Ratos Wistar , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacosRESUMO
AT-101 is a BH3 mimetic and pan-Bcl-2 inhibitor that has shown potent anticancer activity in non-small-cell lung cancer (NSCLC) in murine models, but failed to show clinical efficacy when used in combination with docetaxel in NSCLC patients. Our recent study has demonstrated that AT-101 enhanced the antitumor effect of cisplatin (CDDP) in a murine model of NSCLC via inhibition of the interleukin-6/signal transducer and activator of transcription 3 (STAT3) pathway. This study explored the underlying mechanisms for the enhanced anticancer activity of CDDP by AT-101. Our results show that, when compared with monotherapy, AT-101 significantly enhanced the inhibitory effects of CDDP on proliferation and migration of A549 cells and on tube formation and migration in human umbilical vein endothelial cells. AT-101 promoted the proapoptotic activity of CDDP in A549 cells. AT-101 also enhanced the inhibitory effect of CDDP on DNA repair and redox activities of apurinic/apyrimidinic endonuclease 1 (APE1) in A549 cells. In tumor tissues from nude mice treated with AT-101 plus CDDP or monotherapy, the combination therapy resulted in greater inhibition of angiogenesis and tumor cell proliferation than the monotherapy. These results suggest that AT-101 can enhance the antitumor activity of CDDP in NSCLC via inhibition of APE1 DNA repair and redox activities and by angiogenesis and induction of apoptosis, but other mechanisms cannot be excluded. We are now conducting a Phase II trial to examine the clinical efficacy and safety profile of combined use of AT-101 plus CDDP in advanced NSCLC patients.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/farmacologia , Gossipol/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/administração & dosagem , Reparo do DNA/efeitos dos fármacos , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Gossipol/administração & dosagem , Gossipol/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Oxirredução/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Gossypol is a chemical present in the seeds of cotton plants (Gossypium sp.) that reduces fertility in farm animals. Vitamin E is an antioxidant and may help to protect cells and tissues against the deleterious effects of free radicals. The aim of this study was to evaluate the mechanisms of reproductive toxicity of gossypol in rats and the protective effects of vitamin E. Forty Wistar rats were used, divided into four experimental groups (n = 10): DMSO/ saline + corn oil; DMSO/saline + vitamin E; gossypol + corn oil; and gossypol + vitamin E. RESULTS: Fertility was significantly reduced in male rats treated with gossypol in that a significant decrease in epididy-mal sperm count was observed (P < 0.05) and the number of offspring was significantly reduced in females mated with them (P < 0.05). This dysfunction was prevented by vitamin E. Gossypol caused a significant increase in the activity of the enzymes glutathione peroxidase (P < 0.01) and glutathione reductase (P < 0.01), but vitamin E did not reduce the enzyme activities (P > 0.05). The levels of reduced glutathione and pyridine nucleotides in testis homogen-ate were significantly reduced by gossypol (P < 0.05 and P < 0.01, respectively) and this reduction was accompanied by increased levels of oxidized glutathione (P < 0.05). Vitamin E showed a preventive effect on the changes in the levels of these substances. Gossypol significantly increased the levels of malondialdehyde (P < 0.01), a lipid peroxida-tion indicator, whereas treatment with vitamin E inhibited the action of the gossypol. Vitamin E prevented a decrease in mitochondrial ATP induced by gossypol (P < 0.05). CONCLUSIONS: This study suggests that the reproductive dysfunction caused by gossypol may be related to oxidative stress and mitochondrial bioenergetic damage and that treatment with vitamin E can prevent the infertility caused by the toxin.
Assuntos
Animais , Masculino , Feminino , Gravidez , Ratos , Vitamina E/farmacologia , Gossipol/farmacologia , Anticoncepcionais Masculinos/farmacologia , Fertilidade/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Gossipol/efeitos adversos , Peroxidação de Lipídeos/efeitos dos fármacos , Ratos Wistar , Estresse Oxidativo/efeitos dos fármacos , Glutationa Peroxidase , Glutationa Redutase , MalondialdeídoRESUMO
The present study aimed to determine if gossypol interferes with ovarian follicles in rats. Twenty-four female Wistar rats were assigned to two equal groups: one control group and the other dosed with gossypol (25 mg/kg/day, subcutaneously) for 15 days. Ovarian follicles were histologically classified according to the stage of development and as normal or atretic. Gossypol treatment reduced the length of estrous with an increase in the duration of the diestrus phase. This compound was responsible for reduced serum levels of T4 and progesterone. Treatment with gossypol was responsible for a significant reduction in the number of normal ovarian follicles and a significant increase in the number of atretic follicles, both in all stages of development. Thus, treatment of rats with gossypol was responsible for reduction in the number of viable follicles and changes in hormone levels that resulted in interference of the estrous cycle.
Assuntos
Anticoncepcionais Masculinos/efeitos adversos , Ciclo Estral/efeitos dos fármacos , Gossipol/efeitos adversos , Folículo Ovariano/metabolismo , Progesterona/sangue , Animais , Anticoncepcionais Masculinos/farmacocinética , Ciclo Estral/sangue , Feminino , Gossipol/farmacologia , Folículo Ovariano/patologia , Ratos , Ratos WistarRESUMO
Gossypol is a natural disesquiterpene that blocks the activity of the mammalian facilitative hexose transporter GLUT1. In human HL-60 cells, which express GLUT1, Chinese hamster ovary cells overexpressing GLUT1, and human erythrocytes, gossypol inhibited hexose transport in a concentration-dependent fashion, indicating that blocking of GLUT1 activity is independent of cellular context. With the exception of red blood cells, the inhibition of cellular transport was instantaneous. Gossypol effect was specific for the GLUT1 transporter since it did not alter the uptake of nicotinamide by human erythrocytes. Gossypol affects the glucose-displaceable binding of cytochalasin B to GLUT1 in human erythrocyte ghost in a mixed noncompetitive way, with a K(i) value of 20 microM. Likewise, GLUT1 fluorescence was quenched approximately 80% by gossypol, while Stern-Volmer plots for quenching by iodide displayed increased slopes by gossypol addition. These effects on protein fluorescence were saturable and unaffected by the presence of D-glucose. Gossypol did not alter the affinity of D-glucose for the external substrate site on GLUT1. Kinetic analysis of transport revealed that gossypol behaves as a noncompetitive inhibitor of zero-trans (substrate outside but not inside) transport, but it acts as a competitive inhibitor of equilibrium-exchange (substrate inside and outside) transport, which is consistent with interaction at the endofacial surface, but not at the exofacial surface of the transporter. Thus, gossypol behaves as a quasi-competitive inhibitor of GLUT1 transport activity by binding to a site accessible through the internal face of the transporter, but it does not, in fact, compete with cytochalasin B binding. Our observations suggest that some effects of gossypol on cellular physiology may be related to its ability to disrupt the normal hexose flux through GLUT1, a transporter expressed in almost every kind of mammalian cell and responsible for the basal uptake of glucose.
Assuntos
Eritrócitos/efeitos dos fármacos , Transportador de Glucose Tipo 1/antagonistas & inibidores , Glucose/metabolismo , Gossipol/farmacologia , 3-O-Metilglucose/metabolismo , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Sítios de Ligação , Ligação Competitiva , Células CHO , Cricetinae , Cricetulus , Citocalasina B/metabolismo , Desoxiglucose/metabolismo , Relação Dose-Resposta a Droga , Eritrócitos/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Gossipol/metabolismo , Células HL-60 , Humanos , Cinética , Modelos Biológicos , Niacinamida/metabolismo , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Espectrometria de Fluorescência , TransfecçãoRESUMO
Com o objetivo estudar o efeito de dieta contendo gossipol sobre a qualidade seminal e morfologia dos testículos de touros da raça Nelore, utilizaram-se 16 animais, distribuídos em dois tratamentos: T1, oito touros submetidos a dieta contendo 20 por cento de caroço de algodão e T2, oito touros submetidos a dieta isenta de gossipol. Realizaram-se coletas de sêmen para avaliar a qualidade seminal. Os testículos dos animais foram retirados ao final dos 73 dias de experimento, fragmentos dos mesmos foram preparados para serem analisados em microscopia eletrônica de transmissão e outros fixados em lâminas e corados por hematoxilina-eosina. O consumo médio de caroço de algodão/animal/dia de 1,71kg interferiu na morfologia dos testículos; os túbulos seminíferos apresentaram menor espessura de parede, redução no número de camadas de células espermatogênicas e no volume dos núcleos da célula de Sertoli em relação aos do T2. Por microscopia eletrônica observouse que os touros do T1 apresentavam células de Sertoli com membrana citoplasmática enrugada, acúmulo de lipídeos no citoplasma, mitocôndrias deformadas e algumas espermátides estavam em apoptose. Touros do T1 apresentaram redução na motilidade espermática, aumento no percentual de defeitos espermáticos maiores e totais em relação aos animais do T2. O gossipol alterou a morfologia testicular e reduziu a qualidade espermática dos touros [...]
We studied the effect of a gossypol-enriched diet on the quality of semen and the morphology of testes of Nelore bulls. Sixteen animals were scheduled for 2 treatments: T1, 8 bulls fed a diet containing 20 percent cottonseed and T2, 8 bulls fed a gossypol-free diet. Semen samples were collected in order to evaluate the semen quality. At the end of the 73-day period of treatment, the testes were removed and tissue fragments were prepared for transmission electron microscopy or fixed on slides and stained with haematoxylin-eosin for light microscopy. The mean daily intake of cottonseed by T1 bulls was 1.71 kg/animal, which interfered on testes morphology; the seminiferous tubules had less thick walls, fewer layers of the spermatogenic lineage cells and reduced volumes of Sertoli cell nuclei with regard to T2 bulls. Electron microscopy analyses revealed that the Sertoli cells from T1 animals had a rough cytoplasmic membrane, lipid accumulation in the cytoplasm, deformed mitochondriae; in addition, some apoptotic spermatids were seen. T1 bulls showed reduction of sperm motility and an increase of the percentage of major and total sperm defects in relation to the animals of T2 group. It is concluded that a gossypol-enriched diet promoted alterations in the testicles morphology and it reduced the sperm quality of bulls [...]
Assuntos
Masculino , Animais , Bovinos , Anticoncepcionais Masculinos/farmacologia , Dieta/veterinária , Gossipol/farmacologia , Sêmen , Testículo/ultraestrutura , Microscopia EletrônicaRESUMO
Com o objetivo estudar o efeito de dieta contendo gossipol sobre a qualidade seminal e morfologia dos testículos de touros da raça Nelore, utilizaram-se 16 animais, distribuídos em dois tratamentos: T1, oito touros submetidos a dieta contendo 20 por cento de caroço de algodão e T2, oito touros submetidos a dieta isenta de gossipol. Realizaram-se coletas de sêmen para avaliar a qualidade seminal. Os testículos dos animais foram retirados ao final dos 73 dias de experimento, fragmentos dos mesmos foram preparados para serem analisados em microscopia eletrônica de transmissão e outros fixados em lâminas e corados por hematoxilina-eosina. O consumo médio de caroço de algodão/animal/dia de 1,71kg interferiu na morfologia dos testículos; os túbulos seminíferos apresentaram menor espessura de parede, redução no número de camadas de células espermatogênicas e no volume dos núcleos da célula de Sertoli em relação aos do T2. Por microscopia eletrônica observouse que os touros do T1 apresentavam células de Sertoli com membrana citoplasmática enrugada, acúmulo de lipídeos no citoplasma, mitocôndrias deformadas e algumas espermátides estavam em apoptose. Touros do T1 apresentaram redução na motilidade espermática, aumento no percentual de defeitos espermáticos maiores e totais em relação aos animais do T2. O gossipol alterou a morfologia testicular e reduziu a qualidade espermática dos touros [...](AU)
We studied the effect of a gossypol-enriched diet on the quality of semen and the morphology of testes of Nelore bulls. Sixteen animals were scheduled for 2 treatments: T1, 8 bulls fed a diet containing 20 percent cottonseed and T2, 8 bulls fed a gossypol-free diet. Semen samples were collected in order to evaluate the semen quality. At the end of the 73-day period of treatment, the testes were removed and tissue fragments were prepared for transmission electron microscopy or fixed on slides and stained with haematoxylin-eosin for light microscopy. The mean daily intake of cottonseed by T1 bulls was 1.71 kg/animal, which interfered on testes morphology; the seminiferous tubules had less thick walls, fewer layers of the spermatogenic lineage cells and reduced volumes of Sertoli cell nuclei with regard to T2 bulls. Electron microscopy analyses revealed that the Sertoli cells from T1 animals had a rough cytoplasmic membrane, lipid accumulation in the cytoplasm, deformed mitochondriae; in addition, some apoptotic spermatids were seen. T1 bulls showed reduction of sperm motility and an increase of the percentage of major and total sperm defects in relation to the animals of T2 group. It is concluded that a gossypol-enriched diet promoted alterations in the testicles morphology and it reduced the sperm quality of bulls [...](AU)
Assuntos
Animais , Masculino , Bovinos , Testículo/ultraestrutura , Gossipol/farmacologia , Anticoncepcionais Masculinos/farmacologia , Sêmen , Dieta/veterinária , Microscopia EletrônicaRESUMO
Com o objetivo estudar o efeito de dieta contendo gossipol sobre a qualidade seminal e morfologia dos testículos de touros da raça Nelore, utilizaram-se 16 animais, distribuídos em dois tratamentos: T1, oito touros submetidos a dieta contendo 20 por cento de caroço de algodão e T2, oito touros submetidos a dieta isenta de gossipol. Realizaram-se coletas de sêmen para avaliar a qualidade seminal. Os testículos dos animais foram retirados ao final dos 73 dias de experimento, fragmentos dos mesmos foram preparados para serem analisados em microscopia eletrônica de transmissão e outros fixados em lâminas e corados por hematoxilina-eosina. O consumo médio de caroço de algodão/animal/dia de 1,71kg interferiu na morfologia dos testículos; os túbulos seminíferos apresentaram menor espessura de parede, redução no número de camadas de células espermatogênicas e no volume dos núcleos da célula de Sertoli em relação aos do T2. Por microscopia eletrônica observouse que os touros do T1 apresentavam células de Sertoli com membrana citoplasmática enrugada, acúmulo de lipídeos no citoplasma, mitocôndrias deformadas e algumas espermátides estavam em apoptose. Touros do T1 apresentaram redução na motilidade espermática, aumento no percentual de defeitos espermáticos maiores e totais em relação aos animais do T2. O gossipol alterou a morfologia testicular e reduziu a qualidade espermática dos touros...
We studied the effect of a gossypol-enriched diet on the quality of semen and the morphology of testes of Nelore bulls. Sixteen animals were scheduled for 2 treatments: T1, 8 bulls fed a diet containing 20 percent cottonseed and T2, 8 bulls fed a gossypol-free diet. Semen samples were collected in order to evaluate the semen quality. At the end of the 73-day period of treatment, the testes were removed and tissue fragments were prepared for transmission electron microscopy or fixed on slides and stained with haematoxylin-eosin for light microscopy. The mean daily intake of cottonseed by T1 bulls was 1.71 kg/animal, which interfered on testes morphology; the seminiferous tubules had less thick walls, fewer layers of the spermatogenic lineage cells and reduced volumes of Sertoli cell nuclei with regard to T2 bulls. Electron microscopy analyses revealed that the Sertoli cells from T1 animals had a rough cytoplasmic membrane, lipid accumulation in the cytoplasm, deformed mitochondriae; in addition, some apoptotic spermatids were seen. T1 bulls showed reduction of sperm motility and an increase of the percentage of major and total sperm defects in relation to the animals of T2 group. It is concluded that a gossypol-enriched diet promoted alterations in the testicles morphology and it reduced the sperm quality of bulls...
Assuntos
Animais , Masculino , Bovinos , Anticoncepcionais Masculinos/farmacologia , Gossipol/farmacologia , Sêmen , Testículo/ultraestrutura , Microscopia EletrônicaRESUMO
The constituents of the leaves of Garcinia intermedia and heartwood of Calophyllum brasiliense were investigated based on their trypanocidal activity against epimastigotes of Trypanosoma cruzi, the etiologic agent of Chagas' disease. As the active components, the polyisoprenylated benzophenone derivative guttiferone A and the xanthone 8-desoxygartanin were isolated along with the biflavonoids podocarpusflavone A and amentoflavone, and friedelin from the former. Three xanthones, jacareubin, 6-deoxyjacareubin, and 1,3,5,6-tetrahydroxy-2-(3-methyl-2-butenyl)xanthone from the latter showed activity. The trypanocidal activity of these compounds against trypomastigotes, an infectious form of T. cruzi, was examined as well as gossypol, berberine chloride, and harmine for comparison.