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BACKGROUND AND AIMS: A novel bioactive peptide, mitochondrial-derived peptide (MOTS-c), has recently attracted attention as a potential prevention or therapeutic option for obesity and type 2 diabetes mellitus (T2DM). MOTS-c profiles have not yet been reported in human obesity and T2DM. We aimed to determine circulating MOTS-c levels in obesity and explore the association between MOTS-c levels and various metabolic parameters. METHODS: In this case-control study, 40 obese children and adolescents (27 males) and 57 controls (40 males) were recruited in the Hubei Province of China in 2017. Circulating MOTS-c levels were measured, clinical data (eg, glucose, insulin, and lipid profile) were recorded, and anthropometric measurements were performed. Finally, we investigated correlations between MOTS-c levels and related variables. RESULTS: MOTS-c levels were significantly decreased in the obese group compared with the control group (472.61 ±22.83 vs 561.64 ±19.19 ng/mL, P <.01). After classification by sex, MOTS-c levels were significantly decreased in obese male children and adolescents compared to their counterparts (465.26 ±24.53 vs 584.07 ±21.18 ng/mL, P <.001), while they were comparable between the obese and healthy female subjects (487.89 ±49.77 vs 508.85 ±38.76 ng/mL, P >.05). Further, MOTS-c levels were negatively correlated with body mass index (BMI), BMI SD score, waist circumference, waist-to-hip ratio, fasting insulin level, homeostasis model assessment of insulin resistance (HOMA-IR), and glycated hemoglobin (HbA1c) in the male cohort. CONCLUSIONS: Circulating MOTS-c levels were decreased in obese male children and adolescents and correlated with markers of insulin resistance and obesity.
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Porcine ß-defensin 2 (pBD2), a recently discovered porcine defensin that is produced by the intestine, exerts antimicrobial activities and innate immune effects that are linked to intestinal diseases in pigs. Here, we report a codon-optimised protein corresponding to mature pBD2 cDNA that was expressed and purified in Pichia pastoris yeast. The highest amount of secreted protein (3,694.0 mg/L) was reached 144 h into a 150-h induction during high-density cultivation. Precipitation followed by gel exclusion chromatography yielded 383.7 mg/L purified recombinant pBD2 (rpBD2) with a purity of ~93.7 %. Two recombinant proteins of 5,458.5 and 5,258.4 Da were detected in the mass spectrum due to variation in the amino-terminus. The rpBD2 exhibited high antimicrobial activity against a broad range of pig pathogenic bacteria (minimal inhibitory concentration [MIC] 32-128 µg/mL); the highest activity was observed against Salmonella choleraesuis, Staphylococcus aureus and Streptococcus suis (MIC 32-64 µg/mL). However, rpBD2 also inhibited the growth of probiotics such as Lactobacillus plantarum, Bacillus subtilis and Saccharomyces cerevisiae, but at lower efficacies than the pathogens. Purified or unpurified rpBD2 also maintained high activity over a wide range of pH values (2.0-10.0), a high thermal stability at 100 °C for 40 min and significant resistance to papain, pepsin and trypsin. In addition, the activity of rpBD2 towards S. aureus was unaffected by 10 mM dithiothreitol (DTT) and 20 % dimethyl sulphoxide (DMSO). Our results suggest that pBD2 could be produced efficiently in large quantities in P. pastoris and be a substitute for traditional antibiotics for growth promotion in the porcine industry.
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Alimentación Animal/análisis , Pichia/genética , Porcinos/crecimiento & desarrollo , beta-Defensinas/genética , beta-Defensinas/metabolismo , Animales , Bacterias/efectos de los fármacos , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/veterinaria , Pruebas de Sensibilidad Microbiana , Pichia/química , Pichia/metabolismo , Ingeniería de Proteínas , Porcinos/genética , Porcinos/metabolismo , Enfermedades de los Porcinos/microbiología , beta-Defensinas/aislamiento & purificación , beta-Defensinas/farmacologíaRESUMEN
INTRODUCTION: Arsenicals have a special place in the history of human health, acting both as poison and medicine. Having been used to treat a variety of diseases in the past, the success of arsenic trioxide (ATO) in treating acute promyelocytic leukemia (APL) in the last century marked its use as a drug in modern medicine. To expand their role against cancer, there have been clinical uses of arsenicals worldwide and progress in the development of drug delivery for various malignancies, especially solid tumors. AREAS COVERED: In this review, conducted on Google Scholar [1977-2024], we start with various forms of arsenicals, highlighting the well-known ATO. The mechanism of action of arsenicals in cancer therapy is then overviewed. A summary of the research progress in developing new delivery approaches (e.g. polymers, inorganic frameworks, and biomacromolecules) in recent years is provided, addressing the challenges and opportunities in treating various malignant tumors. EXPERT OPINION: Reducing toxicity and enhancing therapeutic efficacy are guidelines for designing and developing new arsenicals and drug delivery systems. They have shown potential in the fight against cancer and emerging pathogens. New technologies and strategies can help us harness the potency of arsenicals and make better products.
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Antineoplásicos , Trióxido de Arsénico , Arsenicales , Sistemas de Liberación de Medicamentos , Neoplasias , Humanos , Trióxido de Arsénico/administración & dosificación , Trióxido de Arsénico/uso terapéutico , Trióxido de Arsénico/farmacocinética , Neoplasias/tratamiento farmacológico , Arsenicales/administración & dosificación , Arsenicales/uso terapéutico , Arsenicales/farmacocinética , Antineoplásicos/administración & dosificación , Animales , Desarrollo de Medicamentos , Diseño de Fármacos , Leucemia Promielocítica Aguda/tratamiento farmacológicoRESUMEN
Blue egg coloring is attributed to biliverdin derived from the oxidative degradation of heme through catalysis by heme oxygenase (HO). The pigment is secreted into the eggshell by the shell gland. There is uncertainty as to whether the pigment is synthesized in the shell gland or in other tissues. To investigate the site of pigment biosynthesis, the expression of heme oxygenase (decycling) 1 (HMOX1), a gene encoding HO, and HO activity in liver and spleen were compared between blue-shelled chickens (n = 12) and brown-shelled chickens (n = 12). There were no significant differences in HMOX1 expression and HO activity in these tissues between the two groups. Since the liver and spleen, two important sites outside the shell gland where heme is degraded into biliverdin, CO and Fe(2+), did not differ in HO expression and activity we conclude that the pigment is most likely synthesized in the shell gland.
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OBJECTIVE: To investigate the maturation of individual bones on the hand and wrist in children with central precocious puberty (CPP) and idiopathic short stature (ISS). METHODS: Hand and wrist films of 25 children with CPP, 29 children with ISS and 21 normal controls were evaluated by conventional Greulich-Pyle (GP) atlas method and individual bone assessment method, in which all twenty bones of the hand and wrist were evaluated based on GP atlas, including 2 radius and ulna, 7 carpal bones, 11 metacarpal and phalangeal bones, the average bone age (BA) was calculated. The differences in groups were analyzed by independent samples t test. The differences between the two methods were analyzed by paired sample t test. The differences between BA and chronological age (CA) were analyzed by ROC with SPSS 17.0. RESULTS: Compared with the normal control group, the advance of BA in the CPP group was 0.70-2.26 y (1.48 ±0.78) by the GP atlas method, while that was 0.28-2.00 y(1.14 ±0.86) by the individual bone evaluation method. In all twenty bones, the advance of metacarpal and phalangeal BA was the greatest [0.34-2.06 y(1.2±0.86)]. In the ISS group,the delay of BA was 0.47-2.91 y(-1.69±1.22) by the GP atlas method, while that was 0.48-2.50 y (-1.49±1.01) by individual bone evaluation method.The delay of carpal BA was the greatest [0.59-2.73 y(-1.66±1.07)] in all twenty bones. In the ISS group and the normal control group, there were no statistic differences between the two methods. In the CPP group, statistic difference was found between two methods. There were no statistic differences for the areas under ROC curves between two methods. CONCLUSION: The advance of metacarpal and phalangeal BA is the greatest in CPP group and the delay of carpal BA is the greatest in ISS group.Both methods provide diagnostic information for bone age in CPP and ISS children.
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Determinación de la Edad por el Esqueleto/métodos , Enanismo/diagnóstico por imagen , Mano/diagnóstico por imagen , Pubertad Precoz/diagnóstico por imagen , Huesos del Carpo/diagnóstico por imagen , Estudios de Casos y Controles , Niño , Femenino , Humanos , MasculinoRESUMEN
Objective: To explore the risk factors for neonatal congenital hypothyroidism (CH) and the influencing factors of false-positive results in CH screening. Methods: In this study, 255 neonatal patients with CH who completed the screening and further diagnosis and 366 neonates with positive CH screening results and normal thyroid function were selected as the case group. 246 healthy neonates with normal thyroid function were selected as the control group. Gestational age, birth-weight, maternal age, small for gestational age (SGA), perinatal factors (gestational thyroid dysfunction, gestational diabetes mellitus, etc.) were used as influencing factors, using χ 2 tests were performed for comparison. The statistically significant variables were analyzed with Logistic multiple regression models, and the difference was considered statistically significant (P<0.05). Results: There were statistical differences in the SGA, maternal gestational diabetes mellitus, thyroid disease, and the proportion using assisted reproduction technology among the case group, false-positive screening group, and control group (χ 2 was 11.943, 6.857, 6.999, 9.732, respectively, P < 0.05). The results of multivariate logistic regression analysis showed that the gestational thyroid disease (OR = 8.452, 95% CI:1.051-67.982), gestational diabetes mellitus (OR = 2.654, 95% CI:1.051-6.706), and assisted reproduction (OR = 0.194, 95% CI:0.041-0.911) were the influencing factors for neonatal CH, and the difference was statistically significant (P < 0.05). The SGA (OR = 2.556, 95% CI:1.027-6.361), gestational thyroid disease (OR = 7.801, 95% CI:1.03-59.057), gestational diabetes mellitus (OR = 2.731, 95% CI:1.18-6.322), and assisted reproduction (OR = 0.28, 95% CI:0.102-0.765) were the influencing factors of the false-positive screening results of neonatal CH. The difference was statistically significant (P < 0.05). Conclusion: Neonatal CH and positive screening results are influenced by assisted reproduction, gestational thyroid dysfunction, gestational diabetes mellitus, and SGA.
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Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of phototoxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid peroxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P<0.0001) than those of y in the UV-exposed groups, but not for the control. On the other hand, UV exposure had an adverse effect on courtship of flies. Stronger electron paramagnetic resonance (EPR) signals could be detected in w, e and y exposed to 5 min UV. And there were more significant changes of EPR signals in y than in w and e. UVR had no significant (P=0.1782) effect on the SOD activities. After pooling data from the control and UV-exposed groups, we found that w had a significantly (P<0.05) higher level of SOD activity, but e and y were nearly at the same levels (P>0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In conclusion, our results suggested that UVR can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals. w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding against UV and scavenging free radicals produced by UVR should be responsible for their different sensitivity to UVR.
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Fenómenos Bioquímicos , Cortejo , Drosophila melanogaster/metabolismo , Drosophila melanogaster/efectos de la radiación , Fertilidad/fisiología , Animales , Conducta Animal , Color , Drosophila melanogaster/genética , Espectroscopía de Resonancia por Spin del Electrón , Femenino , Masculino , Malondialdehído/metabolismo , Mutación/genética , Superóxido Dismutasa/metabolismo , Tasa de SupervivenciaRESUMEN
Background: Fibroblast growth factor 1 (FGF1) can regulate glucose and lipid metabolism in obese mice. Serum FGF1 has increased in type 2 diabetes mellitus adults and correlated with BMI. This study aimed to indicate conventional weight loss effects on FGF1 in obese children and adolescents. Materials and Methods: Clinical and metabolic parameters of 88 lean and obese individuals (ages 515 years) and 39 obese individuals followed with 6 months of lifestyle intervention were collected. Serum FGF1 levels were detected through enzyme-linked immunosorbent assays. Results: FGF1 levels were increased in obese individuals. Serum FGF1 levels were significantly correlated with BMI and waist circumferences (r = 0.377, P = 0.012; r = 0.301, P = 0.047, respectively). Multivariate stepwise linear regression analyses showed that FGF1 levels were significantly correlated with HbA1c and HOMA-IR (ß = 0.371, P = 0.008; ß = 0.323, P = 0.021, respectively). Weight loss (2.3 ± 0.1 kg) was accompanied by a significant reduction of circulating FGF1 levels (7.2 ± 0.4 pg/mL). Changes in FGF1 were significantly correlated with changes in fasting glucose, HOMA-IR and low-density lipoprotein cholesterol (ß = 0.277, P = 0.020; ß = 0.474, P < 0.001; ß = 0.320, P = 0.008, respectively). Conclusion: FGF1 levels were increased in obese individuals. Serum FGF1 levels were significantly correlated with BMI and waist circumferences (r = 0.377, P = 0.012; r = 0.301, P = 0.047, respectively). Multivariate stepwise linear regression analyses showed that FGF1 levels were significantly correlated with HbA1c and HOMA-IR (ß = 0.371, P = 0.008; ß = 0.323, P = 0.021, respectively). Weight loss (2.3 ± 0.1 kg) was accompanied by a significant reduction of circulating FGF1 levels (7.2 ± 0.4 pg/mL). Changes in FGF1 were significantly correlated with changes in fasting glucose, HOMA-IR and low-density lipoprotein cholesterol (ß = 0.277, P = 0.020; ß = 0.474, P < 0.001; ß = 0.320, P = 0.008, respectively).
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Wnt1-inducible signaling pathway protein-1 (WISP1), a member of the CCN family, is increasingly being recognized as a potential target for obesity and type 2 diabetes mellitus. Recent studies have shown that WISP1 can regulate low-grade inflammation in obese mice, and circulating WISP1 levels are associated with obesity and type 2 diabetes mellitus in adults. Herein, we measured serum WISP1 levels in obese youth and explored its relationships with pro-inflammatory cytokine interleukin 18 (IL-18) and other metabolic indexes. Totally, 44 normal-weight and 44 obese children and adolescents were enrolled. Physical and laboratory data were recorded, and then serum levels of WISP1 and IL-18 were determined by enzyme-linked immunosorbent assays. Results showed that serum levels of WISP1 were significantly higher in obese children and adolescents than in normal-weight healthy controls (1735.44±15.29 vs. 1364.08±18.69 pg/mL). WISP1 levels were significantly positively correlated with body mass index (BMI) and BMI z-score (r=0.392, P=0.008; r=0.474, P=0.001, respectively) in obese group; circulating IL-18 was increased in obese individuals (1229.06±29.42 vs. 295.87±13.30 pg/mL). Circulating WISP1 levels were significantly correlated with IL-18 (r=0.542, P<0.001), adiponectin (r=0.585, P<0.001) and leptin (r=0.592, P<0.001). The multivariate stepwise regression analysis showed that higher IL-18 levels represented the main determinant of increased WISP1 levels after adjusting for BMI, waist circumference, fasting insulin, homeostatic model assessment of insulin resistance (HOMA-IR) and HbA1c in obese individuals (ß=0.542, P=0.000). WISP1 can be involved in glucose/lipid metabolism in obese youth, which may be modulated by IL-18. Increased WISP1 levels may be a risk factor of obesity and insulin resistance, and WISP1 has a potential therapeutic effect on insulin resistance in obese children and adolescents.
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Proteínas CCN de Señalización Intercelular/sangre , Diabetes Mellitus Tipo 2/sangre , Interleucina-18/sangre , Obesidad/sangre , Proteínas Proto-Oncogénicas/sangre , Adolescente , Glucemia , Índice de Masa Corporal , Niño , Preescolar , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Glucosa/metabolismo , Hemoglobina Glucada/metabolismo , Humanos , Insulina/sangre , Resistencia a la Insulina/genética , Metabolismo de los Lípidos/genética , Masculino , Obesidad/genética , Obesidad/fisiopatología , Circunferencia de la Cintura , Proteína Wnt1/genéticaRESUMEN
Post-weaning diarrhoea (PWD) in piglets is associated with colonization of the intestine with bacterial pathogens. In this study, we evaluated the use of recombinant porcine ß-defensin 2 (rpBD2) as a medicated feed additive for weaned piglets. The crude extract from the culture supernatant of rpBD2-expressing Pichia pastoris was used as a medicated feed additive for weaned piglets. Dietary treatments included a positive control (basal diet + antibiotics, designated PC) and three different rpBD2 treatments without antibiotics (basal diet supplemented with 1, 5, or 15 g of crude rpBD2/kg basal diet, designated 1PD, 5PD, and 15PD, respectively). Of all the treatments, 5PD had the greatest impact on the weaned piglets. It increased their body weight, average daily weight gain, average daily feed intake, and intestinal villus height in the duodenum and jejunum, and reduced the incidence of PWD. The diversity of the cecal digesta and mucosa microflora was compared between the weaned piglets in the PC and 5PD groups. Piglets treated with 5PD had lower diversity indices and fewer bacterial pathogens in their cecal digesta and mucosa than the PC group. Our results demonstrate that crude rpBD2 could provide an alternative to the traditional antibiotic feed additives given to weaned piglets.
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Alimentación Animal , Antiinfecciosos/uso terapéutico , Diarrea/veterinaria , Aditivos Alimentarios/uso terapéutico , Enfermedades de los Porcinos/prevención & control , beta-Defensinas/uso terapéutico , Animales , Antiinfecciosos/administración & dosificación , Bacterias/clasificación , Bacterias/aislamiento & purificación , Peso Corporal/efectos de los fármacos , Ciego/microbiología , Diarrea/microbiología , Diarrea/prevención & control , Evaluación Preclínica de Medicamentos , Ingestión de Alimentos , Aditivos Alimentarios/administración & dosificación , Microbioma Gastrointestinal/efectos de los fármacos , Intestino Delgado/efectos de los fármacos , Intestino Delgado/ultraestructura , Microvellosidades/ultraestructura , Pichia , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/uso terapéutico , Ribotipificación , Alineación de Secuencia , Staphylococcus aureus/efectos de los fármacos , Porcinos , Enfermedades de los Porcinos/microbiología , Destete , beta-Defensinas/administración & dosificación , beta-Defensinas/genéticaRESUMEN
A total of 64 5-month-old Pietrain pigs were randomly allocated to four treatments with four replicates per treatment according to body weight. The pigs were fed either a standard corn-soybean meal based control diet (treatments 1 and 2), the standard diet with 1% Lycium barbarum (LB) (treatment 3), or the standard diet with 1% Polygala tenuifolia Willd (PT) (treatment 4). Serum lactic acid and glucose concentrations were increased in stressed pigs (P < 0.05). Addition of the herbs in the diet had no effect on the serum lactic acid concentration, but 1% LB decreased (P < 0.05) serum glucose concentration in the stressed pigs. Pre-slaughter stress also decreased (P < 0.01) liver glycogen concentration and the decrease could be inhibited by addition of 1% LB in the diet (P > 0.05). Pre-slaughter stress increased the concentration of maleic dialdehyde (MDA) (P < 0.05) and decreased glutathione peroxidase (GSH-Px) activity in serum, while dietary 1% LB increased (P < 0.05) the activity of GSH-Px and decreased the concentration of MDA in the serum. In conclusion, pre-slaughter stress induces oxidative stress in pigs and dietary supplementation with 1% LB improves antioxidant capacity in stressed pigs before slaughtering.
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Mataderos , Alimentación Animal , Antioxidantes , Dieta/veterinaria , Suplementos Dietéticos , Glucólisis/efectos de los fármacos , Lycium , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/fisiología , Plantas Medicinales , Polygala , Estrés Fisiológico/fisiología , Porcinos/metabolismo , Porcinos/fisiología , Animales , Glucemia/metabolismo , Femenino , Ácido Láctico/sangre , Masculino , Glycine max , Zea maysRESUMEN
BACKGROUND: Incidence of type 2 diabetes mellitus (T2DM) has increased in young people in recent years and new therapies are required for its effective treatment. Glucagon-like peptide 1 (GLP-1) is a potent blood glucose-lowering hormone produced in the L cells of the intestine. It may be potentially effective in the treatment of hyperglycemia in patients with T2DM. DATA SOURCES: PubMed database were searched with the terms "GLP-1", "incretins" and "diabetes". RESULTS: GLP-1 is a product of the glucagon gene, and its secretion is controlled by both neural and endocrine signals. GLP-1 lowers plasma glucose by stimulating insulin and suppressing secretion of glucagons, thus inhibiting gastric emptying and reducing appetite. GLP-1 exerts these actions by the engagement of structurally distinct G-protein-coupled receptors (GPCRs). In patients with T2DM, GLP-1 increases insulin secretion and normalizes both fasting and postprandial blood glucose when given as a continuous intravenous infusion. However, the native hormone is unsuitable as a drug because it is broken down rapidly by dipeptidyl peptidase IV (DPP-4) and cleared by the kidneys. Fortunately, many GLP-1 agonists or analogues and DPP-4 inhibitors have been found or developed, such as exendin-4, exenatide, liraglutide, CJC1131, vidaliptin and P32/98. Clinical trials have shown their therapeutic functions in T2DM with little adverse reaction. CONCLUSION: A GLP-1 based therapy will be safe and effective for the treatment of T2DM.
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Diabetes Mellitus Tipo 2/terapia , Péptido 1 Similar al Glucagón/uso terapéutico , Incretinas/uso terapéutico , Animales , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/fisiopatología , Terapia Genética , Péptido 1 Similar al Glucagón/agonistas , Péptido 1 Similar al Glucagón/análogos & derivados , Receptor del Péptido 1 Similar al Glucagón , Humanos , Hipoglucemiantes/uso terapéutico , Incretinas/análogos & derivados , Incretinas/fisiología , Insulina/metabolismo , Secreción de Insulina , Receptores de Glucagón/agonistasRESUMEN
OBJECTIVE: Fluctuations in arterial oxygen are associated with development of severe retinopathy of prematurity (ROP) in humans. However, the causal relationship between oxygen variability and ROP remains unknown. The authors developed a rat model of retinal neovascularization by repeated fluctuations of inhaled oxygen between hypoxia and hyperoxia to investigate the mechanism of the development of retinal neovascularization, the regulation of vascular endothelial growth factor (VEGF) and KDR/Flk-1 (VEGFR-2) expression. METHODS: Two hundred and eight newborn Sprague Dawley rats were randomly divided into oxygen and air groups. The oxygen concentration in the oxygen group was alternated between 50% and 10% every 24 hours for 14 days. The control group were kept in room air environment. VEGF and Flk-1 expression was observed at 14, 18 and 25 days after birth in both exposed group and control group by immunohistochemical staining and semiquantitative RT-PCR. The status of retinal vasculature on day 4 after oxygen exposure was also observed. The retinas were dissected and stained by using a histochemical method for detecting adenosine diphosphatase (ADPase) activity, digital images of the retinas were captured and the peripheral avascular retina were measured. HE staining on methacrylate sections of eyes was used for counting the number of nuclei extending from retinal area into vitreous to identify extraretinal neovascularization. Numeric data were expressed as the mean +/- standard deviation (SD). Statistical calculations were performed using the SAS 8.1 statistical package. Differences in measured variables between experimental and control groups were determined using comparison of the means using two-way analysis of variance (ANOVA) statistical calculations and T-test. AP value less than 0.05 was regarded as significant. RESULTS: (1) The animal model was successfully established: the avascular areas of retina of 18-day-old rats were larger than those of the control group and the numbers of nuclei extending from retinal area into vitreous in exposed group were significantly higher compared to the control (P < 0.05). (2) The expression of VEGF and Flk-1 on the 14(th) day in the oxygen group was significantly stronger than that of the control group (P < 0.05). In the oxygen group, VEGF and Flk-1 expression was the strongest in the retina on the 18(th) day, the result had significant difference as compared with the 14(th) and 25(th) day (P < 0.05), and they were also stronger than that of the control group (P < 0.05). The expression of VEGF and Flk-1 decreased on the 25(th) day and had no significant difference as compared with the control group (P > 0.05). (3) Both VEGF-mRNA and Flk-1-mRNA significantly increased on the 14(th) day and the 18th day (P < 0.05). On the 25(th) day, the amounts of VEGF-mRNA and Flk-1-mRNA were similar between the control and oxygen group (P > 0.05). CONCLUSION: Fluctuation in oxygen is associated with the development of retinal neovascularization in the retinopathy. Increased expressions of VEGF and Flk-1 in the oxgen fluctuations-induced neovascularized retina suggested that VEGF and Flk-1 might play a critical role in the pathogenesis of ROP. The results also indicated the positive feedback in the pathogenesis of ROP that the synergistic interaction of VEGF and Flk-1 in the retinal vascular proliferation. These findings provide insight into the effect of repeated oxygen fluctuation on the development of severe ROP in preterm infants.
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Modelos Animales de Enfermedad , Oxígeno/efectos adversos , Neovascularización Retiniana/patología , Retinopatía de la Prematuridad/patología , Animales , Humanos , Hiperoxia/patología , Hipoxia/patología , Recién Nacido , Ratas , Ratas Sprague-Dawley , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Inflammation contributes greatly to the pathogenesis of bronchopulmonary dysplasia. In previous studies, we showed that blocking neutrophil influx by treatment with SB265610, a selective CXCR2 antagonist, could partly reduce superoxide accumulation and preserve alveolar development in 60% O(2)-exposed newborn rats. The purpose of this study was to further investigate the role of neutrophils in the formation of reactive oxygen and nitrogen species mediating hyperoxia-impaired lung development. We found that hydroxyl radical formation and lipid peroxidation in rat lungs were significantly increased during 60% O(2) exposure. These increases were attenuated by the administration of SB265610. In addition, SB265610 largely inhibited protein nitration induced by hyperoxia. SB265610 partly prevented the hyperoxia-enhanced bronchoalveolar lavage (BAL) protein content in 60% O(2)-exposed animals. Our results demonstrate that neutrophils have a pivotal role in hydroxyl radical formation, lipid peroxidation and protein nitration. Taken together with our previous studies, the present findings show that blocking neutrophil influx protects alveolar development and improves lung function in part by preventing reactive oxygen/nitrogen species accumulation.