RESUMO
Low-grade body inflammation is a major cause of osteoarthritis (OA), a common joint disease. Gut dysbiosis may lead to systemic inflammation which can be prevented by probiotic administration. The Lactobacillus delbrueckii subsp. lactis 557 (LDL557) has been demonstrated to have beneficial effects for anti-inflammation. This study investigated the effects of LDL557 on OA progress using monosodium iodoacetate (MIA)-induced OA of rats. Live or heat-killed (HK)-LDL557 of a low or high dose was administrated for two weeks before MIA-induced OA, and then continuously administrated for another six weeks. After taking supplements for eight weeks, OA progress was analyzed. Results showed that MIA induced knee joint swelling, chondrocyte damage, and cartilage degradation, and supplementation with a high dose of LDL557 reduced MIA-induced knee joint swelling, chondrocyte damage, and cartilage degradation. Additionally, MIA increased serum levels of the matrix-degrading enzyme MMP-13, while a high dose of HK-LDL557 decreased it for the controls. Simultaneously, bone turnover markers and inflammatory cytokines of serum were assayed, but no significant differences were found except for a TNF-α decrease from a low dose of live LDL557. These results demonstrated that supplementation with high doses of live LDL557 or HK-LDL557 can reduce the progression of MIA-induced OA in rats.
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Osteoarthritis (OA) is a chronic degenerative disease leading to articular cartilage destruction. Menopausal and postmenopausal women are susceptible to both OA and osteoporosis. S-equol, a soy isoflavone-derived molecule, is known to reduce osteoporosis in estrogen-deficient mice, but its role in OA remains unknown. This study aimed to explore the effect of S-equol on different degrees of menopausal OA in female Sprague-Dawley (SD) rats induced by estrogen deficiency caused by bilateral ovariectomy (OVX) combined with intra-articular injection of mono-iodoacetate (MIA). Knee joint histopathological change; serum biomarkers of bone turnover, including N-terminal propeptide of type I procollagen (PINP), C-terminal telopeptide of type I collagen (CTX-I) and N-terminal telopeptide of type I collagen (NTX-I); the cartilage degradation biomarkers hyaluronic acid (HA) and N-terminal propeptide of type II procollagen (PIINP); and the matrix-degrading enzymes matrix metalloproteinases (MMP)-1, MMP-3 and MMP-13, as well as the oxidative stress-inducing molecules nitric oxide (NO) and hydrogen peroxide (H2O2), were assessed for evaluation of OA progression after S-equol supplementation for 8 weeks. The results showed that OVX without or with MIA injection induced various severity levels of menopausal OA by increasing pathological damage, oxidative stress, and cartilage matrix degradation to various degrees. Moreover, S-equol supplementation could significantly reduce these increased biomarkers in different severity levels of OA. This indicates that S-equol can lessen menopausal OA progression by reducing oxidative stress and the matrix-degrading enzymes involved in cartilage degradation.
Assuntos
Cartilagem Articular , Equol , Menopausa , Ovariectomia , Estresse Oxidativo , Ratos Sprague-Dawley , Animais , Estresse Oxidativo/efeitos dos fármacos , Feminino , Menopausa/efeitos dos fármacos , Ratos , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Equol/farmacologia , Biomarcadores/sangue , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Modelos Animais de Doenças , Óxido Nítrico/metabolismoRESUMO
Osteoarthritis (OA) causes joint pain and disability due to the abnormal production of inflammatory cytokines and reactive oxygen species (ROS) in chondrocytes, leading to cell death and cartilage matrix destruction. Selenium (Se) intake can protect cells against oxidative damage. It is still unknown whether Se supplementation is beneficial for OA. This study investigated the effects of Se on sodium iodoacetate (MIA)-imitated OA progress in human chondrocyte cell line (SW1353 cells) and rats. The results showed that 0.3 µM of Se treatment could protect SW1353 cells from MIA-induced damage by the Nrf2 pathway by promoting the gene expression of glutathione-synthesis-related enzymes such as the glutamate-cysteine ligase catalytic subunit, the glutamate-cysteine ligase modifier subunit, and glutathione synthetase. In addition, glutathione, superoxide dismutase, glutathione peroxidase, and glutathione reductase expressions are also elevated to eliminate excessive ROS production. Moreover, Se could downregulate NF-κB, leading to a decrease in cytokines, matrix proteases, and glycosaminoglycans. In the rats, MIA-induced cartilage loss was lessened after 2 weeks of Se supplementation by oral gavage; meanwhile, glutathione synthesis was increased, and the expressions of pro-inflammatory cytokines were decreased. These results suggest that Se intake is beneficial for OA due to its effects of decreasing cartilage loss by enhancing antioxidant capacity and reducing inflammation.
Assuntos
Cartilagem Articular , Osteoartrite , Selênio , Humanos , Ratos , Animais , NF-kappa B/metabolismo , Condrócitos/metabolismo , Selênio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Glutamato-Cisteína Ligase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Osteoartrite/metabolismo , Estresse Oxidativo , Citocinas/metabolismo , Glutationa/metabolismo , Cartilagem Articular/metabolismoRESUMO
Background: Although arthroscopic screw fixation and suture fixation are mainstream interventions for displaced anterior cruciate ligament avulsion fractures of the tibia, the differences in clinical outcomes between them remain inconclusive. Purpose: To conduct a meta-analysis comparing the clinical and functional outcomes between arthroscopic screw fixation and suture fixation for tibial avulsion fractures. Study Design: Systematic review; Level of evidence, 3. Methods: A systematic review was conducted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and using the PubMed, Embase, and Cochrane Central Register of Controlled Trials databases. Inclusion criteria were English-language articles that compared functional outcomes after screw fixation versus suture fixation for tibial avulsion fractures and had at least 1-year follow-up. Relevant data were extracted and analyzed statistically using the Mantel-Haenszel method and variance-weighted means. Random-effects models were used to generate pooled relative risk (RR) estimates with confidence intervals (CIs). Results: Of 1395 articles initially identified, we included 5 studies with 184 patients (91 patients with screw fixations and 93 patients with suture fixations). The pooled results indicated similar postoperative outcomes for screw fixation and suture fixation: Lysholm score (mean difference [MD], -0.32 [95% CI, -6.08 to 5.44]; P = .91), proportion of International Knee Documentation Committee score grade A (74% vs 74%; RR, 0.63 [95% CI, 0.10-3.95]; P = .63), Tegner score (MD, 0.10 [95% CI: -1.73 to 1.92]; P = .92), and Lachman test results (stable knee joint, 82% vs 82%; RR, 0.99; 95% CI: 0.85-1.16; P = .90). Patients in the screw fixation group had a significantly higher overall subsequent surgery rate (46% vs 19%; RR, 2.33; 95% CI,1.51-3.60; P = .0001) and implant removal rate (44% vs 3%; RR, 8.52; 95% CI, 3.58-20.29; P < .00001) compared with those in the suture fixation group. Nonimplant-related subsequent surgery rates were similar for the 2 groups. Conclusion: The findings indicated a higher risk of subsequent surgery (RR, 2.33) and implant removal (RR, 8.52) after screw fixation when compared with suture fixation for tibial avulsion fractures. However, there were no significant differences in clinical outcome scores between the 2 techniques.
RESUMO
PURPOSE: To investigate the relationship between the lateral femoral notch sign as well as the coronal lateral collateral ligament (LCL) sign and anterior tibial translation using the GNRB arthrometer in patients with anterior cruciate ligament (ACL) injuries. METHODS: Forty-six patients with ACL injuries were retrospectively included from May 2020 to February 2022; four patients were excluded due to incomplete data. Magnetic resonance imaging (MRI) were reviewed for the lateral femoral notch sign and the coronal LCL sign. The GNRB arthrometer was used to evaluate the dynamic anterior tibial translation of the knee, and the side-to-side differences (SSDs) in tibial translation between the injured knee and healthy knee were calculated at different force levels. Two types of slopes for displacement-force curves were acquired. RESULTS: Six patients (14.3%) had the positive lateral femoral notch sign (notch depth > 2.0 mm), and 14 patients (33.3%) had the positive coronal LCL sign. The SSD of the anterior tibial translations under different loads as well as the slopes of displacement-force curves were the same in the positive and negative notch sign groups (p all > 0.05) and between the positive and negative coronal LCL sign groups (p all > 0.05). Meanwhile, the measured notch depth and notch length were also not significantly correlated with the anterior tibial translation SSD in the GNRB. CONCLUSION: The presence of the lateral femoral notch sign and the coronal LCL sign did not indicate greater dynamic tibial laxity as measured using the GNRB.
Assuntos
Lesões do Ligamento Cruzado Anterior , Instabilidade Articular , Ligamentos Laterais do Tornozelo , Lesões do Ligamento Cruzado Anterior/diagnóstico por imagem , Lesões do Ligamento Cruzado Anterior/patologia , Fêmur/diagnóstico por imagem , Fêmur/patologia , Humanos , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/patologia , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Tíbia/diagnóstico por imagemRESUMO
Osteoarthritis (OA) is a common chronic disease with increasing prevalence in societies with more aging populations, therefore, it is causing more concern. S-Equol, a kind of isoflavones, was reported to be bioavailable and beneficial to humans in many aspects, such as improving menopausal symptoms, osteoporosis and prevention of cardiovascular disease. This study investigated the effects of S-Equol on OA progress in which rat primary chondrocytes were treated with sodium nitroprusside (SNP) to mimic OA progress with or without the co-addition of S-Equol for the evaluation of S-Equol's efficacy on OA. Results showed treatment of 0.8 mM SNP caused cell death, and increased oxidative stress (NO and H2O2), apoptosis, and proteoglycan loss. Furthermore, the expressions of MMPs of MMP-2, MMP-3, MMP-9, and MMP-13 and p53 were increased. The addition of 30 µM S-Equol could lessen those caused by SNP. Moreover, S-Equol activates the PI3K/Akt pathway, which is an upstream regulation of p53 and NO production and is associated with apoptosis and matrix degradation. As a pretreatment of phosphoinositide 3-kinases (PI3K) inhibitor, all S-Equol protective functions against SNP decrease or disappear. In conclusion, through PI3K/Akt activation, S-Equol can protect chondrocytes against SNP-induced matrix degradation and apoptosis, which are commonly found in OA, suggesting S-Equol is a potential for OA prevention.
Assuntos
Condrócitos/citologia , Equol/farmacologia , Nitroprussiato/efeitos adversos , Osteoartrite/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condrócitos/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Modelos Biológicos , Osteoartrite/induzido quimicamente , Osteoartrite/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/metabolismo , RatosRESUMO
Osteoarthritis (OA) is characterized with articular cartilage degradation, and monosodium iodoacetate (MIA)-treated chondrocyte is the most commonly used model for mimicking OA progression. Zinc protects chondrocytes from MIA-induced damage. Here, we explored the protective effects of 25⯵M zinc on 5⯵M MIA-treated SW1353â¯cells (human chondrosarcoma cell line) through the analysis of energy metabolism- and autophagy-related parameters. We found that the exposure of SW1353â¯cells to MIA decreased ATP levels, expression of glycolysis-related proteins, including glucose transporter 1, hexokinase 2, and pyruvate dehydrogenase E1 component subunit alpha, and the levels of mitochondrial complex I, II, IV, and V subunits of the oxidative phosphorylation pathway. MIA treatment also decreased the expression of autophagy-related proteins, including autophagic elongation protein 5 (ATG5), ATG7, and microtubule-associated protein 1A/1B light chain 3B (LC3-II) and mitophagy-related proteins, including phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1), ubiquitin, and p62. These results indicate that MIA interferes with energy metabolism and the autophagic clearance of dysfunctional mitochondria (so called mitophagy). Interestingly, zinc exposure could almost completely reverse the effects of MIA, suggesting its potential protective role against OA progression.
Assuntos
Trifosfato de Adenosina/metabolismo , Condrócitos/efeitos dos fármacos , Ácido Iodoacético/antagonistas & inibidores , Mitocôndrias/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Sulfato de Zinco/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Ácido Iodoacético/farmacologia , Mitocôndrias/metabolismo , Células Tumorais CultivadasRESUMO
Osteoarthritis (OA) is an age-related degenerative joint disease characterized by high oxidative stress, chondrocyte death and cartilage damage. Zinc has been implicated in the antioxidant capacity of the cell, and its deficiency might inhibit chondrocyte proliferation. The present study examined the potential of zinc as a preventive supplement against OA using the in vitro chondrosarcoma cell line SW1353 and an in vivo Wistar rat model to mimic OA progress induced by monosodium iodoacetate (MIA). The results demonstrated that, in SW1353 cells, 5 µM MIA exposure increased oxidative stress and decreased the expression of GPx1 and Mn-SOD but still increased GSH levels and HO-1 expression and enhanced the expression of interleukin (IL)-10, IL-1ß, and matrix metalloproteinase (MMP)-13. Zinc addition could block these changes. Besides, the expression of Nrf2 and phosphorylated (p)-Akt was dramatically increased, implicating the p-Akt/Nrf2 pathway in the effects of zinc on MIA-treated cells. A rat model achieved similar results as those of cell culture, and 1.6 mg/kg/day of zinc supplementation is sufficient to prevent OA progress, while 8.0 mg/kg/day of zinc supplementation does not have a better effect. These findings indicate that zinc supplementation exerts a preventive effect with respect to MIA-induced OA progress.
Assuntos
Antioxidantes/farmacologia , Cartilagem Articular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Interleucinas/metabolismo , Metaloproteinases da Matriz/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Osteoartrite/prevenção & controle , Sulfato de Zinco/farmacologia , Animais , Antioxidantes/metabolismo , Cartilagem Articular/enzimologia , Cartilagem Articular/patologia , Linhagem Celular Tumoral , Condrócitos/enzimologia , Condrócitos/patologia , Citoproteção , Heme Oxigenase-1/metabolismo , Humanos , Masculino , Osteoartrite/enzimologia , Osteoartrite/patologia , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacosRESUMO
Epirubicin is an anthracycline and is widely used in tumor treatment, but has toxic and undesirable side effects on wide range of cells and hematopoietic stem cells (HSC). Osteoblasts play important roles in bone development and in supporting HSC differentiation and maturation. It remains unknown whether epirubicin-induced bone loss and hematological toxicity are associated with its effect on osteoblasts. In primary osteoblast cell cultures, epirubicin inhibited cell growth and decreased mineralization. Moreover, epirubicin arrested osteoblasts in the G2/M phase, and this arrest was followed by apoptosis in which both the extrinsic (death receptor-mediated) and intrinsic (mitochondrial-mediated) apoptotic pathways were evoked. The factors involved in the extrinsic apoptotic pathway were increased FasL and FADD as well as activated caspase-8. Those involved in the intrinsic apoptotic pathway were decreased Bcl-2; increased reactive oxygen species, Bax, cytochrome c; and activated caspase-9 and caspase-3. These results demonstrate that epirubicin induced osteoblast apoptosis through the extrinsic and intrinsic apoptotic pathways, leading to the destruction of osteoblasts and consequent lessening of their functions in maintaining bone density and supporting hematopoietic stem cell differentiation and maturation.
Assuntos
Apoptose/efeitos dos fármacos , Epirubicina/farmacologia , Mitocôndrias/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Caspases/genética , Caspases/metabolismo , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Proteína de Domínio de Morte Associada a Fas/genética , Proteína de Domínio de Morte Associada a Fas/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Osteoblastos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismoRESUMO
Background: Cancer cells proliferate rapidly and are resistant to cell death, relying on aggravated glycolysis to satisfy their increased demand for energy and biosynthetic precursors. However, this process may create unfavorable microenvironments, such as increased acidity, leading to cytotoxicity. Our previous study demonstrated that arecoline induces anoikis of HA22T/VGH hepatoma cells. The present study aimed to examine if arecoline induced anoikis is related to the glycolytic pathway and explore the underlying mechanisms. Methods: HA22T/VGH cells were treated with arecoline and changes in the glycolytic end products lactate and ATP, glycolytic-related gene expression, intracellular and extracellular pH, pH-regulating gene expression, reactive oxygen species (ROS) levels, intracellular Ca2+ concentration ([Ca2+]i) and mitochondrial membrane potential were examined, relative to untreated cells. Cell viability and morphology were also assessed. Results: Arecoline increased lactate and ATP production through induction of glycolytic genes, including glucose transporter 3 (Glut3), hexokinase 1 (HK1), hexokinase 2 (HK2), and pyruvate kinase (PK). The intracellular pH was not changed, despite increased lactate levels, implying that intracellular H+ was exported out of the cells. mRNA expression of pH regulators including monocarboxylate transporter 1 and 4 (MCT 1 and 4), sodium bicarbonate cotransporter 1 (NBC1), carbonic anhydrases (CA) IX and XII and vacuolar ATPase (V-ATPase) were down-regulated. Na+/H+ exchanger 1 (NHE1) mRNA levels remained unchanged while Na+/Ca2+ exchanger (NCX) was up-regulated and eventually [Ca2+]i was increased. ROS generation was increased and mitochondrial membrane potential was decreased followed by cell detachment and death. Addition of 2-deoxy-d-glucose, a glucose competitor that interferes with glycolysis, attenuated arecoline induction of lactate [Ca2+]i, ROS and cell detachment. Similarly, ROS scavengers could block the effects of arecoline. Conclusions: This study demonstrated that arecoline induced glycolysis and modulated the mRNA expression of pH-regulator genes in HA22T/VGH cells. This phenomenon led to the elevation of [Ca2+]i, ROS generation, and subsequent cell detachment.
RESUMO
Osteoarthritis (OA) is the most prevalent joint disease. Dietary intake of vitamin C relates to a reduction in cartilage loss and OA. This study examined the efficacy of vitamin C to prevent OA with the in vitro chondrosarcoma cell line (SW1353) and the in vivo monosodium iodoacetate (MIA)-induced OA rat. Results demonstrated that, in SW1353 cells, treatment with 5 µM MIA inhibited cell growth and increased oxidative stress, apoptosis, and proteoglycan loss. In addition, the expression levels of the pro-inflammatory cytokines IL-6, IL-17A, and TNF-α and matrix metalloproteinases (MMPs) MMP-1, MMP-3, and MMP-13 were increased. All of these MIA-induced changes could be prevented with treatment of 100 µM vitamin C. In an animal model, intra-articular injection of MIA-induced cartilage degradation resembled the pathological changes of OA, and treatment of vitamin C could lessen these changes. Unexpectedly, vitamin C's effects did not strengthen with the increasing dosage, while the 100 mg/kg dosage was more efficient than the 200 or 300 mg/kg dosages. Vitamin C possessed multiple capacities for prevention of OA progress, including a decrease in apoptosis and in the expression of pro-inflammatory cytokines and MMPs in addition to the well-known antioxidation.
Assuntos
Ácido Ascórbico/farmacologia , Condrócitos/efeitos dos fármacos , Osteoartrite/tratamento farmacológico , Vitaminas/farmacologia , Animais , Apoptose , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/uso terapêutico , Linhagem Celular Tumoral , Citocinas/metabolismo , Humanos , Ácido Iodoacético/toxicidade , Masculino , Metaloproteinases da Matriz/metabolismo , Osteoartrite/etiologia , Osteoartrite/metabolismo , Estresse Oxidativo , Proteoglicanas/metabolismo , Ratos , Ratos Wistar , Vitaminas/administração & dosagem , Vitaminas/uso terapêuticoRESUMO
Arsenic trioxide is used to treat a variety of leukaemia types and causes tumour cell death. However, it is not well known whether arsenic trioxide is toxic to bone osteoblast cells, the precursor cells from which leukaemia cells originate. The aim of this study was to examine the response of osteosarcoma cell line MG63 and primary cultured osteoblasts to arsenic trioxide treatment. After 24h of treatment, arsenic trioxide was more effective at inhibiting cell growth and increasing oxidative stress and DNA damage in MG63 cells than in osteoblasts. In addition, arsenic trioxide arrested cell cycle progression in the G2/M phase, and induced apoptosis in MG63 cells, but not in primary cultured osteoblasts. The results further showed that the expression of transcription factor Nrf2 and its downstream antioxidant effectors, including hemeoxygenase-1, glutathione, and superoxide dismutase, was increased in primary cultured osteoblasts. Additionally, expression of heat shock proteins was also increased. Experiments using inhibitors of antioxidant enzymes in the presence of arsenic trioxide-treated osteoblasts demonstrated that glutathione and superoxide dismutase were responsible for reducing oxidative stress, caspase-3 activity, and apoptosis and that heat shock proteins helped reduce caspase-3 activity. Unexpectedly, there was no apparent effect of the markedly increased hemeoxygenase-1, suggesting that other functions might exist for hemeoxygenase-1. These findings demonstrate that osteosarcoma cells are more sensitive to arsenic trioxide treatment than primary cultured osteoblasts and that primary cultured osteoblasts activate the Nrf2 signalling pathway in response to arsenic trioxide exposure to escape from oxidative damage and apoptosis.
Assuntos
Antineoplásicos/efeitos adversos , Arsenicais/efeitos adversos , Fator 2 Relacionado a NF-E2/metabolismo , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Óxidos/efeitos adversos , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Trióxido de Arsênio , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/metabolismo , Humanos , Osteoblastos/metabolismo , Estresse Oxidativo/efeitos dos fármacosRESUMO
Arsenic trioxide (ATO) is widely used in tumor treatment, but excessive arsenic exposure can have adverse effects. We recently found that, in primary osteoblasts, ATO produces oxidative stress and causes DNA tailing, but does not induce apoptosis. We further examined the signaling pathway by which osteoblasts survive ATO treatment, and found that they were arrested at G2/M phase of the cell cycle at 30h and overrode the G2/M boundary at 48h. After treatment for 30h, there was increased Cdc2 phosphorylation and expression of Wee1, a Cdc2 kinase, and expression of the cell cycle inhibitor, p21(waf1/cip1), which interacts with Cdc2. Furthermore, levels of the phosphatase Cdc25C, which activates Cdc2, were decreased, while the ratio of its phosphorylated/inactivated form to the total amount was increased. Moreover, phosphorylation/activation of the checkpoint kinases Chk1, Chk2 and p53 levels were increased, as were levels of activated ATM and γ-H2AX. The cell viability was decreased as an ATM inhibitor was added. Additionally, these effects of ATO on γ-H2AX, Chk1, Chk2, p53, and p21(waf1/cip1) were reduced by an ATM inhibitor. These findings suggest that G2/M phase arrest of osteoblasts is mediated by Chk1/Chk2 activation via an ATM-dependent pathway by which osteoblasts survive.
Assuntos
Proteínas de Ciclo Celular/fisiologia , Proteínas de Ligação a DNA/fisiologia , Osteoblastos/efeitos dos fármacos , Óxidos/toxicidade , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Animais , Trióxido de Arsênio , Arsenicais , Proteínas Mutadas de Ataxia Telangiectasia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Quinase do Ponto de Checagem 2 , Quinases Ciclina-Dependentes/fisiologia , Dano ao DNA/efeitos dos fármacos , Reparo do DNA , Ativação Enzimática , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Osteoblastos/citologia , Fosforilação , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Transdução de SinaisRESUMO
Arsenic trioxide (ATO) is widely used in tumor treatment, but excessive arsenic exposure can have adverse health effects. This study was to examine the association between ATO treatment and bone remodeling. The effects of ATO on osteoblast function were investigated in primary cell cultures and in an in vivo study in rats. Sprague-Dawley rats (n=30) were randomly assigned to 3 groups which were injected intraperitoneally with saline or 5 or 10 mg/kg of ATO for 4 weeks. In cell culture, ATO decreased osteoblast mineralization by decreasing alkaline phosphatase (ALP) expression and this effect was prevented by co-addition of inorganic phosphate (Pi). Moreover, levels of mRNAs for the transcription factors runt-related transcription factor 2 (Runx2) and osterix, the osteoblast osteogenic gene osteocalcin, and the adherence molecule vascular cell adhesion molecule-1 (VCAM-1) were decreased by ATO. Levels of mRNAs for the cytokine IL-6 were also decreased, whereas GM-CSF mRNA levels were increased. Similar effects of ATO on osteoblasts were seen in in vivo experiments in the rat. Moreover, decreases of bone turnover markers of osteocalcin, Procollagen type I N-terminal propeptide (PINP), and C-terminal cross-linked telopeptide (CTX) as well as bone mineral density (BMD) and trabecular bone volume of femur were observed in ATO-treated rats. These results suggest that ATO interferes with bone remodeling mostly through changes in osteoblast differentiation and function.
Assuntos
Remodelação Óssea/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Óxidos/toxicidade , Fosfatase Alcalina/metabolismo , Animais , Trióxido de Arsênio , Arsenicais , Sequência de Bases , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/genética , Remodelação Óssea/fisiologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Interleucina-6/genética , Masculino , Osteoblastos/patologia , Osteoblastos/fisiologia , Osteocalcina/genética , Osteocalcina/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Peptídeos/metabolismo , Pró-Colágeno/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição/genética , Molécula 1 de Adesão de Célula Vascular/genéticaRESUMO
The cutaneous lesions of incontinentia pigmenti classically evolve in stages, beginning with erythematous vesicular rash and bullae, followed by verrucose lesions, with an eventual macular pattern of splashed or whorled hyperpigmentation. We describe female twins presenting with the classic form of cutaneous expression. Ophthalmologic examination revealed abnormal vascular proliferations in the peripheral retinas in twin B. Several studies have confirmed linkage of familial incontinentia pigmenti to chromosome Xq28, with the factor VIII gene in Xq28 identified as the locus for incontinentia pigmenti. Two-hundred kilobases proximal to this locus, the gene for NEMO (NF-kappaB essential modulator)/IKKgamma (I kappaB kinase-gamma) has been mapped. We describe herein female twins with incontinentia pigmenti caused by a de novo mutation of this locus, as demonstrated by diagnostic polymerase chain reaction.
Assuntos
Doenças Genéticas Ligadas ao Cromossomo X/genética , Incontinência Pigmentar/genética , Proteínas de Transporte/genética , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Humanos , Quinase I-kappa B , Incontinência Pigmentar/patologia , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Mutação , Linhagem , Reação em Cadeia da Polimerase , GêmeosRESUMO
BACKGROUND: Patent ductus arteriosus (PDA) is commonly found in very low-birthweight (VLBW) infants. The presence of respiratory distress syndrome (RDS) is also associated with increased frequency of significant PDA. Intravenous indomethacin has been used to treat and to prevent PDA in premature infants since 1976. However, concern remains regarding the safety of indomethacin, which affects renal, gastrointestinal and cerebral perfusion. Intravenous ibuprofen has recently been used to treat and to prevent PDA premature infants with PDA without reducing cerebral blood flow or affecting intestinal or renal hemodynamics. The aim of the present study is to compare intravenous ibuprofen and indomethacin with regard to efficacy and safety for the early treatment of PDA in preterm infants. METHODS: A total of 63 preterm infants with RDS who had a birthweight of < or =1500 g and gestational age of < or =32 weeks, were enrolled in the present study. All patients were treated with nasal continuous positive airway pressure with additional oxygen supply in inspired air>30%, or with mechanical ventilation. The patients' serum platelet counts were>100,000/uL, and serum creatinine values were <1.5 mg/dL. There were no 3-4 grade intraventricular hemorrhages before randomization, and all patients were aged 2-7 days and had echo-cardio-graphic evidence of significant PDA. Patients were randomized into two groups: the first group of neonates (group A, n = 32) received intravenous ibuprofen lysine 10 mg/kg, followed by 5 mg/kg after 24 and 48 h; the second group (group B, n = 31) received intravenous indomethacin 0.2 mg/kg every 12 h for three doses. RESULTS: Patent ductus arteriosus closed in 27 patients from the ibuprofen group (84.4%) and in 25 patients from the indomethacin group (80.6%). PDA reopened in three patients from the ibuprofen group (9.4%) and in three patients from the indomethacin group (9.7%). One patient in the ibuprofen group and two patients in the indomethacin group required ductal ligation. Serum creatinine and blood urea nitrogen (BUN) concentrations were lower in the ibuprofen group than in the indomethacin group. Urine output and creatinine clearance values were higher in the ibuprofen group than in the indomethacin group. CONCLUSIONS: Ibuprofen therapy is as efficacious as indomethacin for the treatment of PDA in preterm infants. Infants treated with ibuprofen have higher creatinine clearance and urine output and lower serum creatinine and BUN values than infants treated with indomethacin.