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1.
Int J Mol Sci ; 25(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38612416

RESUMO

Acute kidney injury (AKI) is a public health burden with increasing morbidity and mortality rates and health care costs. Acute tubular necrosis (ATN) is the most common cause of AKI. Cisplatin (CIS) is a platinum-based chemotherapeutic agent used in the treatment of a wide variety of malignancies such as lung, breast, ovary, testis, bladder, cervix, and head and neck cancers. Autophagy plays an important role in AKI. Galectin-3 (Gal-3) is significantly increased in renal tubules in AKI; however, its role in autophagy is not well understood. Male C57B6/J and B6.Cg-Lgals3 /J Gal-3 knockout (KO) mice were used to induce AKI using a CIS mouse model of ATN. Renal Gal-3 and autophagy proteins' expression were measured using standard histologic, immunofluorescent, and enzyme-linked immunosorbent assay techniques. The data were presented as the mean ± S.E. Statistically significant differences (p < 0.05) were calculated between experimental groups and corresponding control groups by one-way analysis of variance. There was a significant increase in renal concentrations of Gal-3 in the Gal-3 wild-type CIS-treated mice when compared with sham control mice. There were significantly higher concentrations of renal LC3B, ATG13, Ulk-1, Beclin, ATG5, ATG12, ATG9A, and p-AMPK in the CIS-treated Gal-3 KO mice than in the Gal-3 wild-type CIS-treated mice. Further, there were significantly higher concentrations of mTOR, p- NF-κB, beta-catenin, and p62 in the kidneys of the Gal-3 wild-type CIS-treated mice than in the Gal-3 KO CIS-treated mice. Our findings affirm the connection between Gal-3 and autophagy, revealing its central role as a connector with prosurvival signaling proteins. Gal-3 plays a pivotal role in orchestrating cellular responses by interacting with prosurvival signal pathways and engaging with autophagy proteins. Notably, our observations highlight that the absence of Gal-3 can enhance autophagy in CIS-induced ATN.


Assuntos
Injúria Renal Aguda , Necrose do Córtex Renal , Animais , Masculino , Camundongos , Autofagia , Cisplatino/efeitos adversos , Cisplatino/farmacologia , Galectina 3/genética , Rim , Necrose
2.
Cell Physiol Biochem ; 56(4): 401-417, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36001774

RESUMO

BACKGROUND/AIMS: Doxorubicin (DOXO) is a potent chemotherapeutic drug that is used in the treatment of a large number of cancers. Despite its important chemotherapeutic characteristics, its usage is limited because of the serious side effects; the most noticeable is cardiotoxicity which can manifest acutely or years after completion of treatment leading to left ventricular dysfunction, dilated cardiomyopathy and heart failure. Nootkatone (NK) is a recognized bioactive compound isolated from the heartwood of Cupressus nootkatensis and has been reported to have antiseptic, antioxidant, and anti-allergic activities. METHODS: Male C57B6/J mice were used for mice model of DOXO-cardiac toxicity. Mice were given either DOXO or NK or DOXO+NK or vehicle (normal saline) after which the mice again had free access to food and water. Heart and plasma samples were collected 5 days after DOXO administration and were used for immunohistochemistry, electron microscopy and enzyme linked immunosorbent assay (ELISA). RESULTS: There were significant reduction in inflammatory markers in hearts of DOXO-NK- treated mice when compared with DOXO-treated mice. Moreover, there were significant increase in antioxidant proteins and reduction of oxidative stress in hearts of DOXO-NK-treated mice when compared with DOXO-treated mice. There was a significant reduction in myocardial damage as shown by significant reduction of troponin I in DOXO-NK- treated mice when compared with DOXO-treated mice. CONCLUSION: Nootkatone improves DOXO-induced myocardial injury through modulation of NF-κB signals and reduction of oxidative stress.


Assuntos
Traumatismos Cardíacos , NF-kappa B , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Cardiotoxicidade/metabolismo , Doxorrubicina , Traumatismos Cardíacos/metabolismo , Masculino , Camundongos , Miócitos Cardíacos/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , Sesquiterpenos Policíclicos
3.
Int J Mol Sci ; 23(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36293342

RESUMO

Doxorubicin (DOXO) is an effective drug that is used in the treatment of a large number of cancers. Regardless of its important chemotherapeutic characteristics, its usage is restricted because of its serious side effects; the most obvious is cardiotoxicity, which can manifest acutely or years after completion of treatment, leading to left ventricular dysfunction, dilated cardiomyopathy, and heart failure. Galectin 3 (Gal-3) is a beta galactoside binding lectin that has different roles in normal and pathophysiological conditions. Gal-3 was found to be upregulated in animal models, correlating with heart failure, atherosclerosis, and myocardial infarction. Male C57B6/J and B6.Cg-Lgals3 /J Gal-3 knockout (KO) mice were used for a mouse model of acute DOXO-induced cardiotoxicity. Mice were given DOXO or vehicle (normal saline), after which the mice again had free access to food and water. Heart and plasma samples were collected 5 days after DOXO administration and were used for tissue processing, staining, electron microscopy, and enzyme-linked immunosorbent assay (ELISA). There was a significant increase in the heart concentration of Gal-3 in Gal-3 wild type DOXO-treated mice when compared with the sham control. There were significantly higher concentrations of heart cleaved caspase-3, plasma troponin I, plasma lactate dehydrogenase, and plasma creatine kinase in Gal-3 KO DOXO-treated mice than in Gal-3 wild type DOXO-treated mice. Moreover, there were significantly higher heart antioxidant proteins and lower oxidative stress in Gal-3 wild type DOXO-treated mice than in Gal-3 KO DOXO-treated mice. In conclusion, Gal-3 can affect the redox pathways and regulate cell survival and death of the myocardium following acute DOXO injury.


Assuntos
Galectina 3 , Insuficiência Cardíaca , Masculino , Camundongos , Animais , Galectina 3/genética , Galectina 3/metabolismo , Caspase 3/metabolismo , Cardiotoxicidade/etiologia , Troponina I/metabolismo , Miócitos Cardíacos/metabolismo , Antioxidantes/farmacologia , Solução Salina , Camundongos Endogâmicos C57BL , Doxorrubicina/efeitos adversos , Estresse Oxidativo , Camundongos Knockout , Insuficiência Cardíaca/metabolismo , Creatina Quinase/metabolismo , Água/metabolismo , Lactato Desidrogenases/metabolismo
4.
Cell Physiol Biochem ; 55(3): 344-363, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34171186

RESUMO

BACKGROUND/AIMS: Acute kidney injury (AKI) is a public health burden with increasing morbidity, mortality and health care cost. It is associated with increased risk for the development of chronic kidney disease and death. Acute tubular necrosis (ATN) is the most common cause of AKI. Apoptosis and tissue necrosis play an important role in ATN. Galectin 3 (GAL-3), a beta galactoside binding lectin, is known to have a role in inflammation, apoptosis and oxidative stress but its role in cisplatin induced acute tubular necrosis is not clearly elucidated. METHODS: Male C57B6-J and C57BL-6 -GAL-3 knock-out mice were used to induce ATN using cisplatin mouse model of acute tubular necrosis. GAL-3 expression, apoptotic, necrotic and necroptotic proteins in kidneys were measured using standard histologic, immunohistochemical, and enzyme-linked immunosorbent assay techniques. Data were presented as mean ± S.E. Statistically significant differences (p<0.05) was calculated between experimental groups and corresponding control groups by one-way analysis of variance. RESULTS: There was a significant increase in GAL-3 in kidneys of cisplatin treated GAL-3 wild mice when compared with its control mice. In addition, there were significant higher percentage of ATN, higher levels of plasma urea and creatinine, and higher levels of cathepsin B and cathepsin D, in kidneys of cisplatin-treated GAL-3 KO mice than cisplatin-treated GAL-3 wild mice. Likewise, there were significant higher levels of necroptosis proteins RIPK1, RIPK3, and MLKL in kidneys of cisplatin-treated GAL-3 KO mice than cisplatin-treated GAL-3 wild mice. Moreover, there were significant higher levels of kidney pro-apoptotic proteins; cleaved caspase-3, cleaved PARP, TRAIL and FAS in cisplatin treated GAL-3 KO mice when compared with cisplatin treated GAL-3 wild mice. CONCLUSION: GAL-3 can affect cell survival and death through its interaction with necroptotic, apoptotic and pro-survival proteins in renal tubules during cisplatin-induced acute tubular necrosis.


Assuntos
Injúria Renal Aguda/metabolismo , Cisplatino/efeitos adversos , Galectina 3/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Túbulos Renais/metabolismo , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/genética , Injúria Renal Aguda/patologia , Animais , Cisplatino/farmacologia , Galectina 3/genética , Humanos , Proteínas Inibidoras de Apoptose/genética , Túbulos Renais/patologia , Camundongos , Camundongos Knockout , Necrose
5.
BMC Cancer ; 19(1): 135, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30744593

RESUMO

BACKGROUND: Breast carcinoma is the commonest cancer among UAE population and the most common cancer among females. Examination of the 5' promoter regions of trefoil factor 3 (TFF3) gene has identified putative estrogen and progesterone receptor-DNA binding domains as direct response elements to estrogen and progesterone that are linked to breast functions or steroid regulation. The study was designed to determine the role of TFF3 in breast cancer chemoresistance with the aim of establishing TFF3 expression as a biomarker for drug resistance. METHODS: In total, 133 cases of breast carcinoma treated with neo-adjuvant therapy were collected. Tissue samples from pre-neoadjuvant therapy as well as tissues from post-neo-adjuvant therapy of those cases were collected and stained with immunohistochemistry for TFF3, Bcl2, BAX, cleaved caspase-3, AKT-1, NF kappa B and Ki-67. RESULTS: There was increased expression of TFF3 in residual invasive carcinoma cells. There was a significant correlation between the expression of TFF3 in breast carcinoma cells and response to neoadjuvant chemotherapy (p = 0.0165). There was significant co-expression of TFF3 with AKT1 (p = 0.0365), BCl2 (p = 0.0152), and NF Kappa-B (p = 0.0243) in breast carcinoma cases with residual carcinoma following neoadjuvant therapy which support the role of TFF3 in chemoresistance. CONCLUSION: The expression of TFF3 is significantly associated with residual breast carcinoma following neoadjuvant chemotherapy suggesting its expression is associated with increased resistance to chemotherapy. This is supported by its co-expression with antiapoptotic proteins; BCl2, AKT1 and NF Kappa-B in residual breast carcinoma cells and very low proliferating index and apoptotic bodies in residual tumors.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Fator Trefoil-3/metabolismo , Adulto , Fatores Etários , Apoptose , Biópsia , Neoplasias da Mama/tratamento farmacológico , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Proliferação de Células , Quimioterapia Adjuvante , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Terapia Neoadjuvante , Invasividade Neoplásica , Estadiamento de Neoplasias , Ligação Proteica , Transporte Proteico , Resultado do Tratamento , Fator Trefoil-3/genética
6.
Oncotarget ; 12(9): 923-935, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33953846

RESUMO

Malignant cells commonly use aerobic glycolysis for ATP production; this is known as the Warburg effect, where pyruvate is converted to lactate, by enzyme lactate dehydrogenase A (LDH-A). In this study, we have investigated the effect of inhibition of LDH-A on cells viability and identifying the mechanism of cell death in HeLa and MCF-7 cancer cells. Human cervical cancer HeLa cell line and breast cancer MCF-7 cell line were used to investigate the effect of inhibition of LDH-A by sodium oxamate on cell survival and proliferation using western blot, spectrophotometry, and immunofluorescent study. There was significant reduction in LDH-A (P < 0.001) and cell viability (P < 0.001) in a dose-dependent mode in both HeLa and MCF-7 SO-treated cancer cells. The voltage-dependent anion channel (VDAC) protein was significantly increased (P < 0.001) in association with decreased LDH-A. The proapoptotic proteins; cytochrome C (P < 0.001), BAX (P < 0.001), cleaved caspase-3 (P < 0.001), cleaved caspase-8 (P < 0.001), and cleaved caspase-9 (P < 0.001) were significantly increased in association with decreased LDH-A. While, the anti-apoptotic protein Bcl2 was significantly decreased (P < 0.001) in association with decreased LDH-A. We conclude that Inhibition of LDH-A can decrease cells viability through activation of intrinsic apoptotic pathway via increased VDAC protein and inhibition of Bcl2 as well as activation of the extrinsic apoptotic pathway through activation of caspase-8.

7.
J Chemother ; 32(2): 88-97, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31884896

RESUMO

Idelalisib, an inhibitor of the phosphatidylinositol-3-kinase p110δ subunit (PI3Kδ), is approved for treating lymphoid malignancy. The drug is associated with hematopoietic and pulmonary toxicities, which limit its clinical use. However, the toxicity mechanisms are not completely elucidated. In this study, mice were intraperitoneally injected with idelalisib (40 or 80 µg/g) or dimethyl sulfoxide for five days every week for up to four weeks to evaluate the changes in the thymus, spleen, and pulmonary functions. Idelalisib treatment induced thymic involution, decreased CD4+/CD8+ T-cell population, and increased CD4-/CD8- T-cell population. In the spleen, idelalisib dose dependently decreased the lymphocyte viability and cell count. Idelalisib-treated mice exhibited enhanced cleaved caspase-3 expression in the thymus, spleen, and lung tissues. Idelalisib augmented thoracic and airway resistance and decreased thoracic compliance. Thus, PI3Kδ has physiological roles in T-cell development and airway function. Monitoring drug toxicity is important for developing follow-up compounds that target PI3Kδ signalling.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Tecido Linfoide/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Injeções Intraperitoneais , Pulmão/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Purinas , Quinazolinonas , Transdução de Sinais/efeitos dos fármacos , Baço/efeitos dos fármacos , Timo/efeitos dos fármacos
8.
Biomolecules ; 9(3)2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871269

RESUMO

Anaphylactic shock (AS) is a life-threatening, multisystem disorder arising from sudden release of mast cell- and basophil-derived mediators into the circulation. In this study, we have used a Wistar rat model to investigate AS-associated histopathologic changes in various organs. Rats were sensitized with ovalbumin (1 mg s.c), and AS was induced by intravenous injection of ovalbumin (1 mg). Experimental groups included nonallergic rats (n = 6) and allergic rats (n = 6). Heart rate and blood pressure were monitored during one hour. Organs were harvested at the end of the experiment and prepared for histologic and immunohistochemical studies. Lung, small bowel mucosa and spleen were found to undergo heavy infiltration by mast cells and eosinophils, with less prominent mast cell infiltration of cardiac tissue. The mast cells in lung, small bowel and spleen exhibited increased expression of tryptase, c-kit and induced nitric oxide synthase (iNOS). Increased expression of endothelial nitric oxide synthase (eNOS) by vascular endothelial cells was noted principally in lung, heart and small bowel wall. The Wistar rat model of AS exhibited accumulation of mast cells and eosinophils in the lung, small bowel, and spleen to a greater extent than in the heart. We conclude that lung and gut are principal inflammatory targets in AS, and likely contribute to the severe hypotension of AS. Targeting nitric oxide (NO) production may help reduce AS mortality.


Assuntos
Anafilaxia/imunologia , Anafilaxia/patologia , Hipotensão/patologia , Inflamação/patologia , Ovalbumina/imunologia , Animais , Modelos Animais de Doenças , Hipotensão/imunologia , Inflamação/imunologia , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Óxido Nítrico/biossíntese , Ovalbumina/administração & dosagem , Ratos , Ratos Wistar
9.
Int J Clin Exp Pathol ; 6(12): 2765-77, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24294363

RESUMO

Classic Hodgkin lymphoma (cHL), a germinal-center related B cell neoplasm in almost all cases, is characterized by scarcity of the neoplastic Hodgkin/Reed-Sternberg (H/RS) cells. Epstein-Barr virus (EBV) has been shown to affect cell cycle and regulation of apoptosis. In total, 95 cases of cHL were studied. Five-micrometer sections were prepared and stained with hematoxylin and eosin and immunohistochemical streptavidin-biotin methods for EBV-LMP-1, COX-2, p53, p16, ki-67 and cleaved caspase-3. In-situ hybridization for EBV encoded RNA was used to confirm the detection of EBV in H/RS. There were 49 nodular sclerosis, 32 mixed cellularity, 8 lymphocyte-rich, and 6 lymphocyte-depleted subtypes in this series of cases. EBV, COX-2, p16(INK4A) and p53 were detected in 55% (52/95), 64% (61/95), 62% (59/95), and 65% (62/95) of the cases respectively. EBV was detected in 62% (38/61), 70% (41/59), and 69% (43/62) of COX2, p16 and p53 positive cases respectively. On the other hand, EBV-non-infected cases of cHL are associated with 59% (20/34), 69% (25/36), and 73% (24/33) of COX2, p16 and p53 negative cases respectively. In conclusion, EBV infection is associated with the expression of COX-2, p16(INK4A) and p53. EBV might be the dominant factor in determining the expression of these three proteins.


Assuntos
Biomarcadores Tumorais/análise , Inibidor p16 de Quinase Dependente de Ciclina/análise , Ciclo-Oxigenase 2/análise , Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/metabolismo , Doença de Hodgkin/virologia , Células de Reed-Sternberg/química , Células de Reed-Sternberg/virologia , Proteína Supressora de Tumor p53/análise , Apoptose , Caspase 3/análise , Proliferação de Células , Herpesvirus Humano 4/química , Herpesvirus Humano 4/genética , Doença de Hodgkin/patologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Antígeno Ki-67/análise , RNA Viral/análise , Células de Reed-Sternberg/patologia , Proteínas da Matriz Viral/análise
10.
Toxicol Sci ; 122(1): 86-99, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21470958

RESUMO

We report on the pneumatocyte structure and function of mouse lung specimens exposed in vitro to two calcined mesoporous silica particles, MCM41-cal (spheres, ∼300 to 1000 nm in diameter) and SBA15-cal (irregular rods averaging ∼500 nm in diameter and ∼1000 nm in length). These mesoporous silica particles are in consideration for potential medical application as delivery vehicles for genes, drugs, and bio-imagers. In the study, lung specimens (about 10 mg each) were excised from male Balb/c mice, immediately immersed in Krebs-Henseleit buffer, ice-cold, and continuously gassed with O(2):CO(2) (95:5). The samples were incubated at 37°C in the same buffer with and without 200 µg/mL MCM41-cal or SBA15-cal for 5-14 h. The tissues were then rinsed thoroughly and processed for light and electron microscopy. Normal alveolar morphology was evident in all the studied specimens. There was no significant difference in the number of apoptotic cells between the treated and untreated samples. Despite their relatively large sizes, the particles were abundantly present in pneumocytes, macrophages, endothelial cells, fibroblasts, and interstitium. They were seen in different areas of the cytoplasm, suggesting intracellular movements. Their presence did not appear to disturb cellular configuration or micro-organelles. Due to their rigidity and surface charges, some were firmly attached to (indenting) the nuclear membrane. The rate of respiration (cellular mitochondrial O(2) consumption, in µM O(2)/min/mg) in specimens exposed to 200 µg/mL particles for up to 12 h was the same as untreated specimens. These findings confirm "reasonable" bioavailability and biocompatibility of calcined mesoporous silicas with mouse lung within at least 5-14 h of exposure time.


Assuntos
Células Epiteliais Alveolares/patologia , Materiais Biocompatíveis/farmacologia , Pulmão/efeitos dos fármacos , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Células Epiteliais Alveolares/efeitos dos fármacos , Animais , Materiais Biocompatíveis/toxicidade , Disponibilidade Biológica , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Glucose , Técnicas In Vitro , Pulmão/metabolismo , Pulmão/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Nanoestruturas/química , Tamanho da Partícula , Dióxido de Silício/metabolismo , Dióxido de Silício/toxicidade , Manejo de Espécimes , Trometamina
11.
J Pharmacol Toxicol Methods ; 63(2): 196-204, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21034836

RESUMO

INTRODUCTION: A novel in vitro system was developed to measure O2 consumption by murine tissues over several hours. METHODS: Tissue specimens (7-35 mg) excised from male Balb/c mice were immediately immersed in ice-cold Krebs-Henseleit buffer, saturated with 95% O2:5% CO2. The specimens were incubated at 37 °C in the buffer, continuously gassed with O2:CO2 (95:5). [O2] was determined as a function of time from the phosphorescence decay rates (1/τ) of Pd(II) meso-tetra-(4-sulfonatophenyl)-tetrabenzoporphyrin. The values of 1/τ were linear with [O2]: 1/τ=1/τo + kq [O2]; 1/τo=the decay rate for zero O2, kq=the rate constant in s⁻¹ µM⁻¹. RESULTS: NaCN inhibited O2 consumption, confirming oxidation occurred in the mitochondrial respiratory chain. The rate of respiration in lung specimens incubated in vitro for 3.9≤t≤12.4 h was 0.24±0.03 µM O2 min⁻¹ mg⁻¹ (mean±SD, n=28). The corresponding rate for the liver was 0.27±0.13 (n=11, t≤4.7 h), spleen 0.28± 0.07 (n=10, t≤5h), kidney 0.34±0.12 (n=7, t≤5h) and pancreas 0.35±0.09 (n=10, t≤4h). Normal tissue histology at hour 5 was confirmed by light and electron microscopy. There was negligible number of apoptotic cells by caspase 3 staining. DISCUSSION: This approach allows accurate assessment of tissue bioenergetics in vitro.


Assuntos
Consumo de Oxigênio/fisiologia , Oxigênio/análise , Animais , Transporte de Elétrons/fisiologia , Metabolismo Energético/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Oxirredução , Oxigênio/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Testes de Função Respiratória/métodos , Taxa Respiratória/fisiologia , Cianeto de Sódio/farmacologia
12.
Toxicology ; 263(2-3): 84-92, 2009 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-19560508

RESUMO

Inhaled particulate matter is associated with increased cerebro- and cardiovascular events. However, the systemic mechanisms underlying these effects remain unclear. In the present study, we investigated the mechanisms underlying the relationship between airway and systemic inflammation and pial cerebral venular thrombosis, 24h after intratracheal (i.t.) instillation of diesel exhaust particles (DEP; 15 or 30 microg/mouse) or saline (control). Doses of 15 and 30 microg/mouse induced a dose-dependent macrophage and neutrophil influx into the bronchoalveolar lavage (BAL) fluid with elevation of total proteins and Trolox equivalent antioxidant capacity (TEAC), but without IL-6 release. Similarly, in plasma, IL-6 concentrations did not increase but the TEAC was significantly and dose-dependently decreased. The number of platelets and the tail bleeding time were both significantly reduced after exposure to DEP (30 microg). Interestingly, the same dose showed platelet proaggregatory effect in mouse pial cerebral venules. Pretreatment with the cysteine prodrug l-2-oxothiazolidine-4-carboxylic acid (OTC, 80 mg/kg) 24 and 1h before i.t. DEP (30 microg), abolished the DEP-induced macrophage and neutrophil influx, and the increase of TEAC in BAL. Lung histopathology confirmed the protective effect of OTC on DEP-induced lung inflammation. OTC also reversed the decrease of TEAC concentrations in plasma, the shortening of the bleeding time, and the thrombotic effect of DEP in pial cerebral venules. We conclude that pulmonary exposure to DEP cause oxidative stress responsible, at least partially, for the pulmonary and systemic inflammation and thrombotic events in the pial cerebral microvessels of mice. OTC pretreatment abrogated these effects through its ability to balance oxidant-antioxidant status.


Assuntos
Poluentes Atmosféricos/toxicidade , Trombose Intracraniana/patologia , Pró-Fármacos , Substâncias Protetoras/metabolismo , Ácido Pirrolidonocarboxílico/metabolismo , Tiazolidinas/metabolismo , Emissões de Veículos/toxicidade , Animais , Relação Dose-Resposta a Droga , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos , Microvasos/patologia , Tamanho da Partícula
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