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1.
Neonatology ; 121(2): 195-202, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38043512

RESUMO

INTRODUCTION: The effects of hydrocortisone (HDC) administration to extremely low birth weight (ELBW) infants on later development remain unclear. This study examined the association between HDC dosage during neonatal period and neurodevelopmental outcomes in ELBW infants. METHODS: This study was a retrospective cohort study conducted in eight centers in Japan. The subjects of this study were ELBW infants born between April 2015 and March 2017. The association between postnatal total HDC dosage up to 36 weeks postmenstrual age and the developmental quotient (DQ) at 3 years of age was examined. Multiple linear regression evaluated the association, adjusting for weeks of gestation, birth weight, and the presence of bronchopulmonary dysplasia, late-onset circulatory collapse, intracranial hemorrhage, necrotizing enterocolitis, and sepsis. RESULTS: This study included 218 ELBW infants, of whom 144 underwent a developmental test at 3 years of age. Simple linear regression analysis revealed a significant association between total HDC dosage and DQ at 3 years of age (coefficients: -2.65, 95% CI: -3.73, -1.57). Multiple linear regression analysis adjusted for the presence of bronchopulmonary dysplasia and late-onset circulatory collapse also revealed a significant association between total HDC dosage and DQ at 3 years of age (coefficients: -2.66, 95% CI: -3.89, -1.42). CONCLUSION: Higher total HDC dosage up to 36 weeks postmenstrual age in ELBW infants was associated with impaired neurodevelopmental outcomes. Although HDC is often needed in the treatment of ELBW infants, clinicians should be aware that an increased dose of HDC may be associated with impaired neurodevelopmental outcomes.


Assuntos
Displasia Broncopulmonar , Choque , Lactente , Humanos , Recém-Nascido , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Hidrocortisona , Estudos Retrospectivos
2.
Artigo em Inglês | MEDLINE | ID: mdl-38083610

RESUMO

Fibrosis is a disease that causes abnormal accumulation of collagen and other extracellular matrix components. It can lead to organ failure and is responsible for one-third of all deaths worldwide. However, there is no cure for this disease, and the development of minimally invasive therapies is urgently needed. We have previously reported techniques for adjusting the shape and flexibility of fibrous tissue by traction while denaturing it with heat. However, studies comparing heat and traction on fibrous tissue are limited, so this paper examined that. Applying heat and traction to bovine Achilles tendon tissue has been shown to cause the denaturation of collagen molecules to accumulate in the tissue in response to these loads. Heat-induced collagen denaturation was nondirectional and omnidirectional, whereas mechanical stress-induced collagen denaturation was concentrated in the direction of traction. When both heat and traction were applied, collagen denaturation increased more than under a single load, indicating a synergistic effect.


Assuntos
Colágeno , Animais , Bovinos , Colágeno/fisiologia , Estresse Mecânico
3.
Nagoya J Med Sci ; 83(2): 311-319, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34239179

RESUMO

Premature infants are at risk for developing symptomatic postnatal cytomegalovirus (CMV) disease, including sepsis-like syndrome. We performed a retrospective case-control study including infants born before 32 weeks of gestation and diagnosed with symptomatic postnatal CMV infection during the neonatal period. Neurodevelopmental outcome was evaluated using the Kyoto Scale of Psychological Development 2001 at 18 months of corrected age and at 3 years of age. Twenty-four infants were diagnosed with postnatal CMV infection; of them, 14 had sepsis-like symptoms and 10 had laboratory test abnormalities only. Home oxygen therapy was used significantly higher in the CMV-positive group compared with the control group at hospital discharge (52% vs 21%, P=0.032). The incidence of neurodevelopmental impairment was not significantly different between the two groups at 18 months of corrected age (29% vs 17%, P=0.48) and at 3 years of age (43% vs 29%, P=0.34). Postnatal CMV infection did not have a significant influence on neurodevelopmental outcomes of symptomatic preterm infants, although those in the CMV-positive group appeared worse. Larger studies with long-term follow-up are needed for a better understanding of continued neurodevelopmental outcomes in preterm infants with postnatal CMV infection.


Assuntos
Infecções por Citomegalovirus , Pré-Escolar , Citomegalovirus , Infecções por Citomegalovirus/epidemiologia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Estudos Retrospectivos , Sepse
4.
J AOAC Int ; 103(6): 1610-1618, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33247751

RESUMO

BACKGROUND: PixeeMo™ is a compact instrument that enables bacterial cell counting using microfluidic chips instead of counting of colonies on culture media. Chips containing electrodes, based on fluid, electric filtering and sorting technology (FES), allow the selection of bacterial cells from other components in the sample. In the United States (US), surface water or ground water affected by surface water must be treated to reduce the total microbial load to less than 500 CFU/mL. In Japan, drinking water regulations limit the total bacterial load to 100 CFU/mL. OBJECTIVE: To validate the PixeeMoTM aerobic bacteria method based on the Japanese regulation in the range of 30-300 CFU/mL in drinking water. METHOD: PixeeMoTM aerobic bacteria method was compared to the Standard Method for the Examination of Water and Wastewater (SMEWW) 9215B (2017) using naturally contaminated drinking water. RESULTS: The maximum repeatability standard deviation of the PixeeMoTM method was 14.8%. The difference of mean log10 values between the PixeeMoTM and SMEWW 9215B methods ranged from -0.015 to 0.258. Similar results were obtained in the independent laboratory study. CONCLUSIONS: The PixeeMoTM method is equivalent to that of the SMEWW 9215B methods. The product consistency and stability study demonstrated no significant difference within the expiration date. The robustness study confirmed that there was no effect within the expected range. The instrument variation study also demonstrated no significant difference among the data of three PixeeMoTM instruments. HIGHLIGHTS: Total counts of bacteria in drinking water can be determined accurately within 1 h with PixeeMoTM.


Assuntos
Bactérias Aeróbias , Água Potável , Bactérias , Carga Bacteriana , Contagem de Colônia Microbiana , Japão
5.
Endocrine ; 69(3): 642-649, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32621048

RESUMO

PURPOSE: To evaluate the effects of denosumab (Dmb) on calcium, renal, and bone involvement in osteoporotic patients with primary hyperparathyroidism (PHPT) and compare with those who underwent a parathyroidectomy (PTX) procedure. METHODS: This retrospective, longitudinal study included patients treated with Dmb (60 mg) once every 6 months (n = 19) and those who successfully underwent a PTX procedure (n = 19) corrected calcium (cCa), eGFR, bone mineral density (BMD) in the lumbar spine (LS), total hip (TH), and femoral neck (FN) and LS-trabecular bone score (TBS) changes at 1 year after beginning Dmb or undergoing PTX were measured. RESULTS: Dmb group had older age, and showed milder disease activity and lower eGFR as compared with PTX group. In PTX group, cCa and eGFR were significantly decreased following surgery, while those were stable in Dmb group. There were significant increases in LS, TH, and FN-BMD in both Dmb (LS: 6.0 ± 0.8%, TH: 3.7 ± 1.0%, FN: 4.3 ± 1.5%) and PTX (LS: 11.2 ± 1.5%, TH: 7.5 ± 1.5%, FN: 7.9 ± 2.1%) groups. In Dmb group, LS-TBS was significantly improved by 3.0 ± 1.0%, while TBS change in PTX group approached significance (2.8 ± 1.5%). Percent change in TH-BMD was significantly correlated with baseline tartrate-resistant acid phosphatase-5b (TRACP-5b) in both groups. CONCLUSIONS: Dmb treatment not only increased BMD, dependent on bone turnover status, the same as PTX, but also improved LS-TBS. In addition, it did not decrease the level of eGFR, whereas PTX did. These results suggest that Dmb treatment help in the clinical management of osteoporotic patients with PHPT who do not undergo surgery as alternative to PTX.


Assuntos
Cálcio , Hiperparatireoidismo Primário , Absorciometria de Fóton , Idoso , Densidade Óssea , Denosumab/uso terapêutico , Humanos , Hiperparatireoidismo Primário/complicações , Hiperparatireoidismo Primário/tratamento farmacológico , Hiperparatireoidismo Primário/cirurgia , Estudos Longitudinais , Vértebras Lombares , Paratireoidectomia , Estudos Retrospectivos
6.
Am J Med Genet A ; 179(7): 1253-1259, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30942556

RESUMO

Infants with trisomy 18 (T18) previously had a poor prognosis; however, the intensive care of these patients has markedly diversified the prognosis. We investigated the current situation of patients with T18, clarified factors for survival discharge, and surveyed actual home healthcare. A total of 117 patients with T18 admitted to nine institutions between 2000 and 2015 were retrospectively investigated. After excluding four patients whose outcomes were unclear, we divided 113 patients into two groups-the survival discharge group (n = 52) and the death discharge group (n = 61)-and compared maternal factors, perinatal factors, neonatal factors, and therapeutic factors between the groups. In addition, home healthcare, readmission, utilization of respite care and home nursing, and cause of death among the survival group were surveyed. Fifty-two (44%) patients with T18 survived at discharge and their 1-year survival rate was 29%. The survival group had a longer gestation period, larger physique, and longer survival time, compared to the death group. Independent factors associated with survival discharge were the absence of an extremely low birthweight infant (ELBWI), the absence of esophageal atresia and patent ductus arteriosus, and cardiovascular surgery. All surviving patients required some home healthcare. The most frequent cause of death was a respiratory disorder. We recommend discussing the treatment strategy with families in the presence of neonatologists or pediatric surgeons, who can explain differences in prognosis, based on the gestation period, birthweight, severity of cardiovascular disease, and cardiovascular surgery.


Assuntos
Doenças Cardiovasculares/diagnóstico , Idade Gestacional , Alta do Paciente/tendências , Síndrome da Trissomía do Cromossomo 18/diagnóstico , Adulto , Peso ao Nascer , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/cirurgia , Feminino , Serviços de Assistência Domiciliar , Assistência Domiciliar/métodos , Humanos , Lactente , Mortalidade Infantil/tendências , Recém-Nascido , Masculino , Gravidez , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Síndrome da Trissomía do Cromossomo 18/complicações , Síndrome da Trissomía do Cromossomo 18/mortalidade , Síndrome da Trissomía do Cromossomo 18/cirurgia
7.
Neurosci Lett ; 662: 259-263, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29079432

RESUMO

Peripheral nerve injury often induces abnormal pain states, such as hyperalgesia and allodynia. In this study, we attempted to elucidate how neurons are synaptically integrated into the neuronal circuitry in the spinal dorsal horn and how synaptic connectivity patterns among dorsal horn neurons are altered by peripheral nerve injury. Experiments were performed on 6-8-week-old ICR mice. Partial sciatic nerve ligation was performed. Transverse slices of the lumbar spinal cord were prepared. Spike activities were simultaneously recorded from multiple neurons in the superficial dorsal horn (SDH) using a multi-electrode array system, and cross-correlograms between spike trains of neuron pairs were constructed. In sham-operated control mice, except for the flat cross-correlogram, the most common pattern was a cross-correlogram suggestive of common excitatory synaptic inputs to neuronal pairs. Peripheral nerve ligation increased the incidences of cross-correlograms suggestive of common excitatory synaptic inputs and excitatory synaptic connections, and decreased that of inhibitory synaptic connections. Additionally, bath-applied capsaicin, an agonist for transient receptor potential vanilloid 1 receptor, increased the frequency of action potentials. The effects of capsaicin stimulation on the incidence of cross-correlograms with various patterns were significantly different between sham-operated control and sciatic nerve-ligated mice. The present observations seem to indicate that neurons in the SDH form excitatory and/or inhibitory synapses with nearby neurons, and that synaptic connections among neurons in the SDH may remarkably change after the development of neuropathic pain.


Assuntos
Neuralgia/fisiopatologia , Plasticidade Neuronal/fisiologia , Traumatismos dos Nervos Periféricos/fisiopatologia , Células do Corno Posterior/patologia , Corno Dorsal da Medula Espinal/fisiopatologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Neuralgia/etiologia , Traumatismos dos Nervos Periféricos/complicações
8.
Am J Med Genet A ; 173(10): 2635-2640, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28856870

RESUMO

Trisomy 13 (T13) is accompanied by severe complications, and it can be challenging to achieve long-term survival without aggressive treatment. However, recently, some patients with T13 have been receiving home care. We conducted this study to investigate factors related to home health-care transition for patients with T13.We studied 28 patients with T13 born between January 2000 and December 2014. We retrospectively compared nine home care transition patients (the home care group) and 19 patients that died during hospitalization (the discharge at death group). The median gestational age of the patients was 36.6 weeks, with a median birth weight of 2,047 g. Currently, three patients (11%) have survived, and 25 (89%) have died. The home care group exhibited a significantly longer gestational age (38.9 vs. 36.3 weeks, p = 0.039) and significantly larger occipitofrontal circumference Z score (-0.04 vs. -0.09, p = 0.019). Congenital heart defects (CHD) was more frequent in the discharge at death group, with six patients in the home care group and 18 patients in the discharge at death group (67% vs. 95%, p = 0.047), respectively. Survival time was significantly longer in the home care group than in the discharge at death group (171 vs. 19 days, p = 0.012). This study has shown that gestational age, occipitofrontal circumference Z score at birth, and the presence of CHD are helpful prognostic factors for determining treatment strategy in patients with T13.


Assuntos
Cromossomos Humanos Par 13/genética , Serviços de Assistência Domiciliar/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Síndrome da Trissomia do Cromossomo 13/genética , Síndrome da Trissomia do Cromossomo 13/mortalidade , Adulto , Peso ao Nascer , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
9.
Nutrients ; 9(7)2017 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-28640219

RESUMO

Ascorbic acid (AA) possesses multiple beneficial functions, such as regulating collagen biosynthesis and redox balance in the skin. AA derivatives have been developed to overcome this compound's high fragility and to assist with AA supplementation to the skin. However, how AA derivatives are transferred into cells and converted to AA in the skin remains unclear. In the present study, we showed that AA treatment failed to increase the cellular AA level in the presence of AA transporter inhibitors, indicating an AA transporter-dependent action. In contrast, torisodium ascorbyl 6-palmitate 2-phosphate (APPS) treatment significantly enhanced the cellular AA level in skin cells despite the presence of inhibitors. In ex vivo experiments, APPS treatment also increased the AA content in a human epidermis model. Interestingly, APPS was readily metabolized and converted to AA in keratinocyte lysates via an intrinsic mechanism. Furthermore, APPS markedly repressed the intracellular superoxide generation and promoted viability associated with an enhanced AA level in Sod1-deficient skin cells. These findings indicate that APPS effectively restores the AA level and normalizes the redox balance in skin cells in an AA transporter-independent manner. Topical treatment of APPS is a beneficial strategy for supplying AA and improving the physiology of damaged skin.


Assuntos
Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/administração & dosagem , Fibroblastos/efeitos dos fármacos , Palmitatos/administração & dosagem , Administração Tópica , Ácido Ascórbico/química , Ácido Ascórbico/metabolismo , Linhagem Celular , Epiderme/efeitos dos fármacos , Deleção de Genes , Humanos , Modelos Biológicos , Estrutura Molecular , Estresse Oxidativo , Palmitatos/química , Palmitatos/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
10.
Neurosci Lett ; 636: 270-275, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27984198

RESUMO

Pregabalin (PGB) is a chemical derivative of the inhibitory neurotransmitter γ-aminobutyric acid, and is successfully used for the treatment of neuropathic pain. Substantial evidence suggests that d-serine, an endogenous co-agonist at the strychnine-insensitive glycine site of the NMDA receptor, counteracts the antinociceptive actions of PGB at the level of the spinal cord. In the present study, we examined the impact of PGB treatment on spinal d-serine content and NMDA receptor-mediated synaptic transmission in the superficial dorsal horn of peripheral nerve-ligated neuropathic mice. Mechanical allodynia was assessed using von Frey filaments. On post-surgical day 9 (after 5days of treatment with PGB [50mg/kg] or saline vehicle), the lumbar spinal cord was removed, homogenized, and ultrafiltrated. Supernatant samples were treated with Marfey's reagent and analyzed with liquid chromatography-mass spectrometry to measure d-serine content. In the electrophysiological experiments, tight-seal whole-cell recording was performed on neurons in the superficial dorsal horn of spinal cord slices. Partial sciatic nerve ligation increased spinal d-serine content, increased the NMDA/non-NMDA ratio of EPSC amplitudes, and slowed the decay phase of the NMDA component of EPSCs (NMDA-EPSCs). PGB treatment attenuated mechanical allodynia and reduced spinal d-serine content, decreased the NMDA/non-NMDA ratio, and shortened the decay time of NMDA-EPSCs. Furthermore, bath-applied d-serine attenuated the effects of PGB treatment. Although the precise mechanism for the effect of PGB on d-serine metabolism and abundance is unknown, the antinociceptive action of PGB likely involves the reduction of spinal d-serine content and subsequent attenuation of NMDA receptor-mediated synaptic transmission in the superficial dorsal horn.


Assuntos
Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Neuralgia/tratamento farmacológico , Neurônios/efeitos dos fármacos , Pregabalina/farmacologia , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Neuralgia/metabolismo , Neurônios/metabolismo , Serina/metabolismo , Ácido gama-Aminobutírico/metabolismo
11.
Bioorg Med Chem ; 20(12): 3837-42, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22579618

RESUMO

Sodium dl-α-tocopheryl-6-O-phosphate (1), a water-soluble derivative of vitamin E (dl-α-tocopherol, 2), exhibits protective effects against various type of skin damage. As reported herein, we found that topical application of 1 improves hygroscopicity and water holding capacity in the stratum corneum of hairless mice in vivo by increasing the ceramide content. In normal human epidermal keratinocytes, treatment with 1 increases ceramide levels and enhances gene expression of serine palmitoyltransferase, which catalyzes the first step of ceramide synthesis in vitro. In addition, 1 increases gene expressions of differentiation markers (transglutaminase 1, cytokeratin 10, involucrin and loricrin), and intracellular Ca(2+) concentrations. These results suggest that 1 could be an excellent agent for improving skin moisture-retention by enhancing ceramide synthesis through the induction of differentiation.


Assuntos
Ceramidas/análise , Pele/efeitos dos fármacos , alfa-Tocoferol/farmacologia , Animais , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Ceramidas/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/genética , Humanos , Queratinócitos/química , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Camundongos , Camundongos Pelados , Pele/química , Pele/metabolismo , Esfingosina N-Aciltransferase/genética , Esfingosina N-Aciltransferase/metabolismo , Relação Estrutura-Atividade , alfa-Tocoferol/química
12.
Bioorg Med Chem ; 19(21): 6348-55, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21945458

RESUMO

The water-soluble vitamin E derivative, sodium dl-α-tocopheryl-6-O-phosphate (1), exhibits protective effects against skin damage. As reported herein, we investigated the actions of 1 on the formation of the inflammatory mediator, prostaglandin E(2) (PGE(2)), as compared to dl-α-tocopheryl acetate (2) and dipotassium glycyrrhizin acid (3). In a three-dimensional (3D) human skin model 1 was converted to α-tocopherol (Toc) to a greater extent than 2. Post-treatment using 2% 1 following ultraviolet B (UVB) irradiation for 2h significantly reduced photodamage as indicated by UVB-damaged cell formation and PGE(2) synthesis. In normal human epidermal keratinocytes stimulated with UVB irradiation, or exposed to interleukin-1 beta, tert-butylhydroperoxide or hydrogen peroxide, pre-treatment with 1 (0-2 µM) inhibited PGE(2) production in dose-dependent manner to a greater extent than 2 and 3. Increases in stimulator-induced cyclooxygenase 2 mRNA expression and p38 MAPK phosphorylation were suppressed by pre-treatment with 1. The vitamin C derivative, magnesium L-ascorbyl-2-phosphate, significantly and synergistically, enhanced the inhibitory effects of 1 on PGE(2) production. These results suggest that 1 is a highly potent protective when compared among the examined commercial human skin care products, and that it might be useful for therapeutic and preventive medicine.


Assuntos
Dinoprostona/antagonistas & inibidores , Queratinócitos/efeitos dos fármacos , alfa-Tocoferol/análogos & derivados , Anti-Inflamatórios/farmacologia , Western Blotting , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/biossíntese , Humanos , Técnicas In Vitro , Interleucina-1beta/farmacologia , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Oxidantes/farmacologia , RNA Mensageiro/química , RNA Mensageiro/genética , Protetores contra Radiação/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Pele/citologia , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/efeitos da radiação , Raios Ultravioleta , alfa-Tocoferol/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
13.
Int J Oncol ; 23(6): 1561-7, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14612927

RESUMO

Our previous study showed that tumor invasion of human fibrosarcoma cells HT-1080 is hardly inhibited by ascorbic acid itself (Asc), but inhibited by 2-O-phosphorylated Asc-6-O-palmitylester (Asc2P6Plm) more markedly than 2-O-phosphorylated Asc or Asc-6-O-palmitylester, and that the inhibitory effect may be attributed to an increase in intracellular Asc derived from Asc2P6Plm. In the present study, the mechanism underlying the inhibitory effect of Asc2P6Plm on tumor invasion was analyzed. Migratory ability of the tumor cells was shown to be inhibited in a dose-dependent manner by either treatment with Asc2P6Plm at 50-300 micro M for 1 h or at 10-50 micro M for 18 h as assessed by cell sheet scratching assay. Hydroxyl radicals in homogenates of Asc2P6Plm-treated HT-1080 cells were markedly diminished relative to those of non-treated cells as evaluated by electron spin resonance method using the spin trapping agent DMPO. This may be closely related to attenuation of intracellular gross reactive oxygen species by Asc2P6Plm as was shown with the redox indicator CDCFH-DA. Actin was localized in the vicinity of the cell membrane abundantly in non-treated cells, but was diminished in a time-dependent manner in Asc2P6Plm-treated cells together with disappearance of pseudopods as shown with the actin-directed agent NBD-phallacidin and by immunocytochemical stain. The cell adhesion-controling molecule RhoA was increased time-dependently in the cytoplasm of Asc2P6Plm-treated cells as shown by Western blots. Thus the inhibition of tumor invasion by Asc2P6Plm was shown to be attributed to decrease in both the cell migratory ability and the actin localization near the cell membrane, which may result from an increase in cytoplasmic RhoA and reduction of intracellular ROS that is achieved by enrichment of intracellular Asc derived from Asc2P6Plm.


Assuntos
Actinas/química , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/química , Neoplasias/metabolismo , Proteína rhoA de Ligação ao GTP/fisiologia , Actinas/metabolismo , Ácido Ascórbico/metabolismo , Western Blotting , Linhagem Celular Tumoral , Movimento Celular , Óxidos N-Cíclicos/farmacologia , Relação Dose-Resposta a Droga , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Radical Hidroxila , Imuno-Histoquímica , Microscopia de Fluorescência , Invasividade Neoplásica , Espécies Reativas de Oxigênio , Marcadores de Spin , Fatores de Tempo , Proteína rhoA de Ligação ao GTP/química , Proteína rhoA de Ligação ao GTP/metabolismo
14.
Mol Cell Biochem ; 252(1-2): 17-23, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14577572

RESUMO

To search a regimen for prevention of post-ischemic reperfusional (I/R) injuries, I/R in the liver was induced by 30-min clamping and subsequent unfastening of the portal vein of a rat, which underwent previous i.v. administration with ascorbic acid (Asc) of 1 mg/kg or the autooxidation-resistant pro-vitamin C, 2-O-alpha-D-glucosylated Asc (Asc2G) or 2-O-phosphorylated Asc (Asc2P) of 1 mg Asc equivalent/kg from the viewpoint of utilization of antioxidants that can promptly scavenge I/R-derived reactive oxygen species. The administration with Asc, Asc2P or Asc2G prevented some features of hepatic I/R injuries such as release of hepatic marker enzymes GOT and GPT into the blood vessel, cellular degenerative symptoms including vacuolation and cell fragmentation, and nuclear DNA strand cleavage as detected by TUNEL staining. The preventive effects on I/R injuries were in the order: Asc2G > Asc2P >> Asc. This order of preventive degrees of three anti-oxidants is partly attributable to proper efficiency of conversion to vitamin C and stability in blood stream; Asc2P was moderately converted to a free monoanion form of Asc in human serum, but, in rat serum, so efficiently converted to Asc as to undergo the resultant oxidative decomposition before reaching the liver, whereas Asc2G underwent scarce conversion to Asc in human serum but moderate conversion in rat serum, suggesting that Asc2P might be less cytoprotective against I/R injury than Asc2G in the rat liver in a way different from the human liver. In contrast Asc was so susceptible to autooxidation as to be rapidly decomposed in either rat or human serum. The concentrations of ascorbyl radicals (AscR) in serum were unchanged during I/R for sham-operated rats, but appreciably diminished time-dependently for I/R-operated rats as shown by ESR spectra. A marked increase in serum AscR occurred in rats receiving Asc, Asc2G or Asc2P, but it was time-dependently restored down to the pre-ischemic level of AscR in I/R-operated rats more rapidly than in sham-operated rats. Thus, hepatic I/R injuries were shown to be prevented more markedly by Asc2G or Asc2P than by Asc, which is attributable to efficiencies of both vitamin C conversion and subsequent AscR retention.


Assuntos
DNA/metabolismo , Fígado/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Açúcares Ácidos/farmacologia , Animais , Ácido Ascórbico/sangue , Citoproteção , Espectroscopia de Ressonância de Spin Eletrônica , Hidrólise , Marcação In Situ das Extremidades Cortadas , Fígado/metabolismo , Fígado/patologia , Masculino , Ratos , Ratos Wistar , Traumatismo por Reperfusão/patologia
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