RESUMO
BACKGROUND: Acute lung injury (ALI) always leads to severe inflammation. As inflammation and oxidative stress are the common pathological basis of endotoxin-induced inflammatory injury and ischemic reperfusion injury (IRI), we speculate that remote ischemic preconditioning (RIPC) can be protective for ALI when used as remote inflammatory preconditioning (RInPC). METHOD: A total of 21 Sprague-Dawley rats were used for the animal experiments. Eighteen rats were equally and randomly divided into the control (NS injection), LPS (LPS injection), and RInPC groups. The RInPC was performed prior to the LPS injection via tourniquet blockage of blood flow to the right hind limb and adopted three cycles of 5 min tying followed by 5 min untying. Animals were sacrificed 24 hours later. There were 2 rats in the LPS group and 1 in the RInPC group who died before the end of the experiment. Supplementary experiments in the LPS and RInPC groups were conducted to ensure that 6 animals in each group reached the end of the experiment. RESULTS: In the present study, we demonstrated that the RInPC significantly attenuated the LPS-induced ALI in rats. Apoptotic cells were reduced significantly by the RInPC, with the simultaneous improvement of apoptosis-related proteins. Reduction of MPO and MDA and increasing of SOD activity were found significantly improved by the RInPC. Increasing of TNF-α, IL-1ß, and IL-6 induced by the LPS was inhibited, while IL-10 was significantly increased by RInPC, compared to the LPS group. CONCLUSION: RInPC could inhibit inflammation and attenuate oxidative stress, thereby reducing intrinsic apoptosis and providing lung protection in the LPS-induced ALI in rats.
Assuntos
Lesão Pulmonar Aguda/imunologia , Apoptose/imunologia , Precondicionamento Isquêmico/métodos , Pulmão/imunologia , Transdução de Sinais/imunologia , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/metabolismo , Animais , Caspases/imunologia , Caspases/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Lipopolissacarídeos , Pulmão/metabolismo , Pulmão/patologia , Malondialdeído/imunologia , Malondialdeído/metabolismo , Peroxidase/imunologia , Peroxidase/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Superóxido Dismutase/imunologia , Superóxido Dismutase/metabolismo , Proteína X Associada a bcl-2/imunologia , Proteína X Associada a bcl-2/metabolismoRESUMO
BACKGROUND: Benign prostatic hyperplasia (BPH) is a pathological condition affecting older men. BPH complications often lead to deterioration in the quality of life. Serenoa repens (Saw Palmetto) is used for treating lower urinary tract infections in traditional medicine. METHODS: This study was performed to compare the efficacy of ß-sitosterol enriched saw palmetto oil (VISPO) and conventional saw palmetto oil (SPO) extracted using supercritical fluid extraction, in alleviating the BPH complications using testosterone-induced BPH model rats. The animals received testosterone (5 mg/kg s.c.) with or without SPO and VISPO (200 and 400 mg/kg b.w.) or Finasteride (1 mg/kg b.w.) p.o. for 28 days. At the end of the experiment, overnight fasted animals were euthanized, blood samples collected for serum analysis of testosterone. Prostate tissue histomorphology was examined by hematoxylin and eosin (H&E) staining. Western blot analysis was performed using prostate tissue homogenates. RESULTS: VISPO exhibited superior efficacy compared to SPO as evident from the significant decrease in prostate weight to body weight ratio, serum testosterone level and increase in growth inhibition of prostate tissue compared to BPH group (p < 0.001). Histological examination of prostate tissue samples showed that VISPO treatment was comparatively better than SPO in improving the hyperplastic patterns. Further, VISPO significantly regulated the expression of inflammatory and apoptotic marker proteins in BPH rats. CONCLUSION: Our data provide experimental evidence that ß-sitosterol enriched saw palmetto oil could be higher efficacious in treating the BPH complications compared to the conventional saw palmetto oil preparations.
Assuntos
Fitosteróis/administração & dosagem , Extratos Vegetais/administração & dosagem , Hiperplasia Prostática/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína X Associada a bcl-2/genética , Animais , Cromatografia com Fluido Supercrítico , Humanos , Masculino , Fitosteróis/isolamento & purificação , Fitoterapia , Extratos Vegetais/isolamento & purificação , Próstata/efeitos dos fármacos , Próstata/imunologia , Hiperplasia Prostática/sangue , Hiperplasia Prostática/induzido quimicamente , Hiperplasia Prostática/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Ratos , Ratos Wistar , Serenoa/química , Sitosteroides/administração & dosagem , Sitosteroides/isolamento & purificação , Testosterona/efeitos adversos , Testosterona/sangue , Proteína X Associada a bcl-2/imunologiaRESUMO
This study was designed to examine the potential involvement of reactive oxygen species in skeletal muscle dysfunction linked with stretching in a mouse model and to explore the effects of combined antioxidant intake on peripheral leukocyte apoptosis following eccentrically-biased downhill runs in human subjects. In the mouse model, diaphragmatic muscle was stretched by 30% of its optimal length, followed by 5-min contraction. Muscle function and extracellular reactive oxygen species release was measured ex vivo. In human models, participants performed two trials of downhill running either with or without antioxidant supplementation, followed by apoptotic assay of inflammatory cells in the blood. The results showed that stretch led to decreased muscle function and prominent ROS increase during muscle contraction. In human models, we observed an elevation in circulating leukocyte apoptosis 24-48 hours following acute downhill runs. However, there is an attenuated leukocyte apoptosis following the second bout of downhill run. Interestingly, the combination of ascorbic acid (vitamin C) and α-tocopherol (vitamin E) supplementation attenuated the decrease in B-cell lymphoma 2 (Bcl-2) at 24 hours following acute downhill running. These data collectively suggest that significant ROS formation can be induced by muscle-lengthening associated with eccentric exercise, which is accompanied by compromised muscle function. The combination of antioxidants supplementation appears to have a protective role via the attenuation of decrease in anti-apoptotic protein.
Assuntos
Apoptose/imunologia , Leucócitos/imunologia , Músculo Esquelético/imunologia , Doenças Musculares/imunologia , Condicionamento Físico Animal , Espécies Reativas de Oxigênio/imunologia , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Leucócitos/patologia , Masculino , Camundongos , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Doenças Musculares/patologia , Doenças Musculares/fisiopatologia , Oxirredução/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Vitamina E/farmacologiaRESUMO
The renin angiotensin system (RAS) is essential for the regulation of cardiovascular and renal functions to maintain the fluid and electrolyte homeostasis. Recent studies have demonstrated a locally expressed RAS in various tissues of mammals, which is having pathophysiological roles in those organ system. Interestingly, local RAS has important role during the inflammatory bowel disease pathogenesis. Further to delineate its role and also to identify the potential effects of telmisartan, an angiotensin receptor blocker, we have used a mouse model of acute colitis induced by dextran sulphate sodium. We have used 0.01 and 5mg/kg body weight doses of telmisartan and administered as enema to facilitate the on-site action and to reduce the systemic adverse effects. Telmisartan high dose treatment significantly reduced the disease activity index score when compared with the colitis control mice. In addition, oxidative stress and endoplasmic reticulum stress markers expression were also significantly reduced when compared with the colitis control mice. Subsequent experiments were carried out to investigate some of the mechanisms underlying its anti-inflammatory effects and identified that the mRNA levels of pro-inflammatory cytokines such as tumour necrosis factor α, interleukin 1ß, interleukin 6 and monocyte chemoattractant protein 1 as well as cellular DNA damage were significantly suppressed when compared with the colitis control mice. Similarly the apoptosis marker proteins such as cleaved caspase 3 and 7 levels were down-regulated and anti-apoptotic protein Bcl2 level was significantly upregulated by telmisartan treatment. These results indicate that blockade of RAS by telmisartan can be an effective therapeutic option against acute colitis.
Assuntos
Benzimidazóis/farmacologia , Benzoatos/farmacologia , Colite , Citocinas/imunologia , Sulfato de Dextrana/toxicidade , Doença Aguda , Animais , Caspase 3/imunologia , Caspase 7/imunologia , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/imunologia , Modelos Animais de Doenças , Feminino , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , TelmisartanRESUMO
Therapeutic manipulation of cellular apoptosis holds great promise for malignant and potentially nonmalignant diseases. A relative resistance to apoptosis in RA synovium is associated with increased expression of prosurvival Bcl-2 family members. In this study, we demonstrate that treatment of DBA/1 mice, prior to the onset of CIA with ABT-737, a BH3 mimetic targeting Bcl-2, Bcl-w, and Bcl-x(L), ameliorated disease development. In contrast, treatment of mice with ABT-737 in established CIA did not alter the course of disease. ABT-737 induced lymphopenia, however pathogenic lymphoid populations in CIA mice were less affected, as shown by relatively normal T and B cell responses to CII. Naïve lymphocytes were highly sensitive to apoptosis after culture with ABT-737, but synovial macrophages and neutrophils were not. Mcl-1 was detected in synovial monocyte/macrophages and neutrophils and strikingly, its expression, rather than Bcl-2 and Bcl-x(L), increased in the affected paws and lymphoid organs of mice with CIA. These observations implicate Mcl-1, which is not targeted by ABT-737, in the survival of inflammatory cells in established CIA and suggest that antagonism of Mcl-1 may be more effective in diseases such as RA.
Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Compostos de Bifenilo/farmacologia , Nitrofenóis/farmacologia , Proteínas/antagonistas & inibidores , Sulfonamidas/farmacologia , Proteína bcl-X/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Proteínas Reguladoras de Apoptose , Artrite Experimental/imunologia , Artrite Experimental/patologia , Avaliação Pré-Clínica de Medicamentos , Leucócitos/imunologia , Leucócitos/metabolismo , Linfopenia/induzido quimicamente , Linfopenia/imunologia , Linfopenia/metabolismo , Linfopenia/patologia , Camundongos , Proteína de Sequência 1 de Leucemia de Células Mieloides , Piperazinas/farmacologia , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Membrana Sinovial/imunologia , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia , Proteína bcl-X/metabolismoRESUMO
AIM: In order to express a novel gene named as BCL-G(L); of swine in E.coli and prepare its polyclonal antibody. METHODS: The contig sequence of the gene was predicted and in silicon cloned by blasting the human BCL-G(L); in swine ESTs database in NCBI. The cloning sequence was obtained by RT-PCR from swine spleen. The cloning sequence was identified by sequencing and compared with the contig sequence. Then the gene was cloned into a prokaryotic expression vector pET-32a to construct a recombinant plasmid named as pET32a-BCL-G(L);. The fusion protein pET32a-BCL-G(L); was expressed in E.coli BL21 and purified using a His-tag fusion protein purification kit. Then guinea pigs were immunized with the purified protein to get the specific polyclonal antibody. RESULTS: The titer of the antibody was 1:800 detected by ELISA. The protein BCL-G(L); can be specifically detected by western blot assay using the polyclonal antibody. CONCLUSION: The novel swine gene BCL-G(L); was cloned and expressed in E.coli and its polyclonal antibody was prepared successfully.
Assuntos
Anticorpos/imunologia , Escherichia coli/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Suínos/genética , Animais , Especificidade de Anticorpos , Clonagem Molecular , DNA Complementar/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Vetores Genéticos/genética , Cobaias , Humanos , Isopropiltiogalactosídeo/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Mapeamento por RestriçãoRESUMO
G1-4A, a polysaccharide from an Indian medicinal plant Tinospora cordifolia, was recently shown to protect mice against septic shock by modulating the proinflammatory cytokines. G1-4A also activated B cells polyclonally. The present report describes in detail the molecular events associated with G1-4A-induced immunomodulation in vitro and in vivo. G1-4A treatment led to an increase in the CD69 expression in lymphocytes. G1-4A-induced proliferation of B cells was completely inhibited by PI3K inhibitor Ly294002, mTOR inhibitor rapamycin and NF-kappaB inhibitor plumbagin. Akt, ERK and JNK were activated by G1-4A which finally resulted in the activation of IKK, degradation of IkappaB-alpha and translocation of NF-kappaB to the nucleus. Administration of G1-4A to mice led to splenomegaly and an increase in the numbers of T cells, B cells and macrophages. This increase in spleen cellularity was due to in vivo proliferation of lymphocytes and upregulation of anti-apoptotic genes. Anti-TLR4-MD2 complex antibody inhibited G1-4A-induced B cell proliferation and degradation of IkappaB-alpha suggesting that TLR-4 was a receptor for G1-4A on B cells. Activation of RAW 264.7 macrophages by G1-4A was found to be dependent on ERK and NF-kappaB-mediated signals. The phagocytosis index in peritoneal exudate cells (PEC) isolated from G1-4A treated mice was significantly higher as compared to that in PEC from control mice. G1-4A administration also increased the number of CD11b(+) cells in the PEC without an increase in the total number of PEC. Thus the present understanding of the molecular mechanism of action of G1-4A, a novel non-microbial TLR4 agonist, will pave the way for its application as an immunomodulator and adjuvant.
Assuntos
Adjuvantes Imunológicos/farmacologia , Linfócitos B/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Polissacarídeos/farmacologia , Receptor 4 Toll-Like/agonistas , Adjuvantes Imunológicos/química , Animais , Antígenos CD/imunologia , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos B/imunologia , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/imunologia , Proteínas de Transporte/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cromonas/farmacologia , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Lectinas Tipo C , Ativação Linfocitária , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/imunologia , MAP Quinase Quinase Quinases/metabolismo , Macrófagos/imunologia , Camundongos , Morfolinas/farmacologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/imunologia , NF-kappa B/metabolismo , Naftoquinonas/farmacologia , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia , Fosfatidilinositol 3-Quinases/imunologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Fosfotransferases (Aceptor do Grupo Álcool)/imunologia , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Polissacarídeos/química , Proteínas Quinases/efeitos dos fármacos , Proteínas Quinases/imunologia , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/agonistas , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sirolimo/farmacologia , Esplenomegalia/imunologia , Esplenomegalia/metabolismo , Serina-Treonina Quinases TOR , Tinospora/química , Receptor 4 Toll-Like/imunologiaRESUMO
Impaired neutrophil function has been associated with increased infectious diseases in ruminants. Attachment of neutrophils to endothelium and superoxide production is critical features of their immune activity. Once the infection is cleared, programmed cell death ensures the rapid resolution of inflammation. To develop new natural therapeutics for ruminants, standard extracts of Echinacea angustifolia (Polinacea), Butea frondosa and Curcuma longa (Curcuvet) were first evaluated on ovine neutrophil functions. Curcuvet strongly reduced PMA-stimulated adhesion and superoxide production. Polinacea and B. frondosa extract also reduced these functions, but with less efficacy than Curcuvet. We analyzed the effect of extracts on spontaneous apoptosis and gene expression in neutrophils aged in vitro for up to 22h. IL8 is critical for neutrophil recruitment and the immune response; Bcl2-related proteins, Bcl2A1 and Bax, are key regulators of neutrophil fate. Spontaneous apoptosis strongly increased in ovine neutrophils cultured for 22h (T22), accompanied by an upregulation of IL8 and a decreased Bcl2A1:Bax ratio. Curcuvet stimulated spontaneous apoptosis and inhibited IL8 and Bcl2A1 gene expression at T22, whereas Polinacea and B. frondosa extract inhibited spontaneous apoptosis and stimulated IL8 expression at T22. These results suggest that Curcuvet has antiinflammatory activity, whereas Polinacea and B. frondosa have an immunomodulatory action on sheep neutrophils.
Assuntos
Apoptose/imunologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Extratos Vegetais/farmacologia , Ovinos/imunologia , Animais , Butea/química , Adesão Celular/imunologia , Sobrevivência Celular/imunologia , Curcuma/química , Echinacea/química , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-8/biossíntese , Interleucina-8/genética , Interleucina-8/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Superóxidos/imunologia , Superóxidos/metabolismo , Proteína X Associada a bcl-2/biossíntese , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/imunologiaRESUMO
Administration of kefir and a kefir cell-free fraction (KF) to mice injected with breast tumor cells produced, locally in the mammary gland, different profiles of cells secreting cytokines. Here, the immune cell populations in mammary glands affected by the cyclic consumption of kefir or KF for 2 or 7 d were evaluated using a breast tumor model. Apoptosis was also assayed as another mechanism involved in tumor growth delay. The rate development of tumor cells, IgA(+) cells, and CD4+ and CD8+ T lymphocytes was monitored in mammary gland tissues. The number of Bcl-2(+) cells in the mammary gland was compared with the apoptosis observed in the tumor. Two-day cyclical administration of both products delayed tumor growth and increased the number of IgA(+) cells in the mammary gland. Changes in the balance between CD4+ and CD8+ cells in the mammary gland were observed in mice from the group fed KF cyclically for 2 d, such that the number of CD4+ cells increased when the number of CD8+ cells remained constant. Mice that received 2-d cyclic administration of KF showed significant increases in the number of apoptotic cells and decreases in Bcl-2(+) cells in the mammary gland, compared with the tumor control group. The present study allows a better understanding of the mechanisms (immune and nonimmune) involved in the antitumor effect observed in mice administered kefir or KF. The importance of nonmicrobial components released during milk fermentation to obtain the beneficial antitumor effects is also reported.
Assuntos
Neoplasias da Mama/prevenção & controle , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Produtos Fermentados do Leite/imunologia , Neoplasias Mamárias Experimentais/prevenção & controle , Animais , Antineoplásicos/imunologia , Antineoplásicos/uso terapêutico , Apoptose , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Imunoglobulina A/imunologia , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/imunologia , Neoplasias Mamárias Experimentais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Proto-Oncogênicas c-bcl-2/imunologiaRESUMO
OBJECTIVE: To investigate the effect of Radix Astragali Injection on apoptosis of lymphocytes and immune function in treating patients with systemic lupus erythematosus (SLE). METHODS: Eighty SLE patients were randomly assigned into the routine treatment group (RT) treated with conventional therapy and the Radix Astragali treated group (RA) treated with Radix Astragali Injection besides routine treatment. The expressions of Fas and Bcl-2 antigen on lymphocytes and the changes of T lymphocyte subsets in peripheral blood before and after treatment were observed. RESULTS: After treatment, the expression of Fas antigen on lymphocytes significantly lowered (P < 0.01), and that of Bcl-2 antigen, CD4+ lymphocyte subset and CD4+ / CD8+ ratio significantly increased in both groups (all P < 0.01). However, the changes of Fas antigen expression, CD4+ and CD4+ / CD8+ ratio were more significant in the RA group than those in the RT group (P < 0.05). CONCLUSION: Radix Astragli Injection can enhance the inhibitory function of corticosteroid/immunosuppressant on apoptosis, and regulate the ratio and function of T lymphocyte subsets to normal range, which may be a useful approach for enhancing the efficacy of treatment to SLE.
Assuntos
Apoptose/efeitos dos fármacos , Astragalus propinquus , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Linfócitos/imunologia , Fitoterapia , Adolescente , Adulto , Relação CD4-CD8 , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Humanos , Injeções Intravenosas , Lúpus Eritematoso Sistêmico/imunologia , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Receptor fas/imunologiaRESUMO
Cordyceps sinensis (Chinese caterpillar fungus) is a fungus parasitic on the larvae of Lepidoptera and has been considered to be a precious tonic food and herbal medicine since ancient times in China. Recently, some fungal strains have been isolated from the fruiting bodies of wild C. sinensis, and some of them have been reported to show the same properties as the natural product. In the present study, an EPSF (exopolysaccharide fraction) was prepared from cultivated C. sinensis and its effects on B16 melanoma-bearing mice were investigated. Three doses of EPSF were intraperitoneally administered every 2 days after the day of tumour-cell injection. The experiment was terminated on day 28. Phagocytosis of peritoneal macrophages and proliferation of spleen and thymus lymphocytes were assayed. The tumour metastatic foci on the lung and liver surface were checked. The expression of oncoprotein Bcl-2 in livers and lungs was assayed by a immunohistochemical method. The results showed that EPSF significantly enhanced the Neutral Red uptake capacity of peritoneal macrophages (60 mg/kg, P<0.01; 120 mg/kg, P<0.001) and spleen lymphocyte proliferation (60 mg/kg, P<0.05; 120 mg/kg, P<0.001) in B16-bearing mouse. The metastasis of B16 melanoma cells to lungs (120 mg/kg) and livers (30, 60 and 120 mg/kg) was significantly inhibited by EPSF. Moreover, EPSF decreased the levels of Bcl-2 in the lungs (120 mg/kg) and livers (30, 60 and 120 mg/kg). These results suggest that EPSF has immunomodulatory function and antitumour activity.
Assuntos
Antineoplásicos/administração & dosagem , Ascomicetos/metabolismo , Fatores Imunológicos/administração & dosagem , Melanoma/tratamento farmacológico , Melanoma/secundário , Polissacarídeos/administração & dosagem , Animais , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Melanoma/imunologia , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Resultado do TratamentoAssuntos
Apoptose/fisiologia , Catecolaminas/metabolismo , Hipotálamo/citologia , Hipotálamo/fisiologia , Neurônios/metabolismo , Óxido Nítrico/metabolismo , Animais , Apoptose/efeitos dos fármacos , Caspase 9 , Caspases/imunologia , Caspases/metabolismo , Desidratação , Hipotálamo/efeitos dos fármacos , Masculino , Metiltirosinas/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Óxido Nítrico Sintase/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo I , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos WistarRESUMO
Vascular cell death is a key feature of atherosclerotic lesions and may contribute to the plaque "necrotic" core, cap rupture, and thrombosis. Oxidatively modified low-density lipoproteins (LDLs) are implicated in the pathogenesis of atherosclerosis, and dietary antioxidants are thought to protect the vasculature against LDL-induced cytotoxicity. Because LDL oxidative modification may vary within atherosclerotic lesions, we examined the effects of defined, oxidatively modified LDL species on human arterial smooth muscle cell apoptosis and the cytoprotective effects of vitamin C. Moderately oxidized LDL (0 to 300 microg protein/mL), which has the highest content of lipid hydroperoxides, induced smooth muscle cell apoptosis within 6 hours, whereas native LDL and mildly and highly oxidized LDL had no effect. Moderately oxidized LDL increased cellular DNA fragmentation, release of fragmented DNA into the culture medium, and annexin V binding and decreased mitochondrial dehydrogenase activity and expression of the antiapoptotic mediator Bcl-x(L). Treatment of cells with native LDL together with the lipid hydroperoxide 13(S)-hydroperoxyoctadeca-9Z,11E-dienoic acid (HPODE, 200 micromol/L, 6 to 24 hours) also induced apoptotic cell death. Pretreatment of smooth muscle cells with vitamin C (0 to 100 micromol/L, 24 hours) attenuated the cytotoxicity and apoptosis induced by both moderately oxidized LDL and HPODE. Our findings suggest that moderately oxidized LDL, with its high lipid hydroperoxide content, rather than mildly or highly oxidized LDL, causes apoptosis of human smooth muscle cells and that vitamin C supplementation may provide protection against plaque instability in advanced atherosclerosis.