70 resultados para Hepatic growth factor
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Background. Mesothelial injury is the pivot in the development of adhesions. An increase in the proliferation of mesothelial cells was verified by in vitro studies with the use of keratinocyte growth factor (KGF). This study investigated the influence of KGF associated with thermo-sterilized carboxymethyl chitosan (NOCCts) in the reduction of pericardial adhesions. Methods. An induction model of pericardial adhesion was carried out in 24 pigs. Animals were randomly allocated to receive topical application of KGF, KGF + NOCCts, NOCCts, or saline (control). At 8 weeks, intra-pericardial adhesions were evaluated and a severity score was established. The time spent to dissect the adhesions and the amount of sharp dissection used, were recorded. Histologic sections were stained with sirius red for a morphometric evaluation using a computer-assisted image analysis system. Cytokeratin AE1/AE3 immunostaining were employed to identify mesothelial cells. Results. The severity score expressed in median (minimum to maximum), in relation to the control group (17 [15 to 18]), was lower in the KGF + NOCCts group (7 [6 to 9], p < 0.01) followed by the KGF group (11.5 [9 to 12], 0.01 < p < 0.05) and the NOCCts group (12 [9 to 14], p > 0.05). The dissection time was significantly lower in the KGF + NOCCts group (7.1 +/- 0.6 vs 33.9 +/- 9.2 minutes, p < 0.001). A significantly less sharp dissection was also required in the KGF + NOCCts group. In the adhesion segment, a decreased collagen proportion was found in the KGF + NOCCts group (p < 0.05). Mesothelial cells were present more extensively in groups in which KGF was delivered (p = 0.01). Conclusions. The use of KGF associated with NOCCts resulted in a synergic action that decreases postoperative pericardial adhesions in a highly significant way. (Ann Thorac Surg 2010; 90: 566-72) (C) 2010 by The Society of Thoracic Surgeons
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P>Brazilian Santa Ines (SI) sheep are very well-adapted to the tropical conditions of Brazil and are an important source of animal protein. A high rate of twin births was reported in some SI flocks. Growth and Differentiation Factor 9 (GDF9) and Bone Morphogenetic Protein 15 (BMP15) are the first two genes expressed by the oocyte to be associated with an increased ovulation rate in sheep. All GDF9 and BMP15 variants characterized, until now, present the same phenotype: the heterozygote ewes have an increased ovulation rate and the mutated homozygotes are sterile. In this study, we have found a new allele of GDF9, named FecGE (Embrapa), which leads to a substitution of a phenylalanine with a cysteine in a conservative position of the mature peptide. Homozygote ewes presenting the FecGE allele have shown an increase in their ovulation rate (82%) and prolificacy (58%). This new phenotype can be very useful in better understanding the genetic control of follicular development; the mechanisms involved in the control of ovulation rate in mammals; and for the improvement of sheep production.
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Background: Glutamine and proline are metabolized in the liver and may collaborate on its regeneration. Parenteral nutrition (PN) containing either glutamine or proline was given to partially hepatectomized rats. The total RNA content and growth factor gene expression in hepatic remnants was measured, to determine the effects of these amino acid supplementation on the expression of growth factors during liver regeneration. Methods: Wistar rats nourished (HN) and malnourished (HM) were hepatectomized and divided in two groups: 20 receiving PN enriched with Alanyl-Glutamine (HN-Gln and HM-Gln) and 20 PN enriched with proline+alanine (HN-Pro and HM-Pro). The control groups comprised 7 nourished (CN) and 7 malnourished (CM) rats that didn`t undergo surgery. Growth factor and thymidine kinase mRNA levels were measured by RT-PCR. Results: In nourished rats, total hepatic RNA levels were lower in the HN-Gln and HN-Pro groups (0.75 and 0.63 mu g/mg tissue, respectively) than in control group (1.67 mu g/mg tissue) (P<0.05). In malnourished rats, total hepatic RNA content was higher in the HM-Pro group than FIN-Pro, HM-Gln, and CM (3.18 vs. 0.63, 0.93 and 1.10 mu g/mg, respectively; P<0.05). Hepatocyte growth factor mRNA was more abundant in the HM-Gln group when compared to CM (031 vs. 0.23 arbitrary units) and also in HM-Pro in relation to HM-Gln, HN-Pro, and CM (0.46 vs. 033 and 0.23, respectively, P<0.05). Conclusions: Proline or glutamine supplementation in malnourished rats improves total RNA content in the remnant hepatic tissue. Amino acids administration increased HGF gene expression after partial hepatectomy in malnourished rats, with a greater effect of proline than glutamine.
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The pathophysiology of hepatic osteodystrophy (HO) remains poorly understood. Our aim was to evaluate bone histomorphometry, biomechanical properties, and the role of the growth hormone (GH)/insulin-like growth factor-I (IGF-I) system in the onset of this disorder. Forty-six male Wistar rats were divided into two groups: sham-operated (SO, n = 23) and bile duct-ligated (BDL, n = 23). Rats were killed on day 30 postoperatively. Immunohistochemical expression of IGF-I and GH receptor was determined in liver tissue and in the proximal growth plate cartilage of the left tibia. Histomorphometric analysis was performed in the right tibia, and the right femur was used for biomechanical analysis. The maximal force at fracture and the stiffness of the mid-shaft femur were, respectively, 53% and 24% lower in BDL compared to SO. Histomorphometric measurements showed low cancellous bone volume and decreased cancellous bone connectivity in BDL, compatible with osteoporosis. This group also showed increased mineralization lag time, indicating disturbance in bone mineralization. Serum levels of IGF-I were lower in BDL (basal 1,816 +/- A 336 vs. 30 days 1,062 +/- A 191 ng/ml, P < 0.0001). BDL also showed higher IGF-I expression in the liver tissue but lower IGF-I and GH receptor expression in growth plate cartilage than SO. Osteoporosis is the most important feature of HO; BDL rats show striking signs of reduced bone volume and decreased bone strength, as early as after 1 month of cholestasis. The endocrine and autocrine-paracrine IGF-I systems are deeply affected by cholestasis. Further studies will be necessary to establish their role in the pathogenesis of HO.
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Chronic and excessive alcohol consumption has been related to an increased risk of several cancers, including that of the liver; however, studies in animal models have yet to conclusively determine whether ethanol acts as a tumor promoter in hepatic tumorigenesis. We examined whether prolonged alcohol consumption could act as a hepatic tumor promoter after initiation by diethylnitrosamine (DEN) in a rat model. Male Sprague-Dawley rats were injected with 20 mg DEN/kg body weight 1 wk before introduction of either an ethanol liquid diet or an isoenergic control liquid diet. Hepatic pathological lesions, hepatocyte proliferation, apoptosis, PPAR alpha and PPAR gamma, and plasma insulin-like growth factor 1 IGF-1) levels were assessed after 6 and 10 mo. Mean body and liver weights, plasma IGF-1 concentration, hepatic expressions of proliferating cellular nuclear antigen and Ki-67, and cyclin D1 in ethanol-fed rats were all significantly lower after 10 mo of treatment compared with control rats. In addition, levels of hepatic PPAR gamma protein, not PPAR alpha, were significantly higher in the ethanol-fed rats after prolonged treatment. Although ethanol feeding also resulted in significantly fewer altered hepatic foci, hepatocellular adenoma was detected in ethanol-fed rats at 10 mo, but not in control rats given the same dose of DEN. Together, these results indicate that chronic, excessive ethanol consumption impairs normal hepatocyte proliferation, which is associated with reduced IGF-1 levels, but promotes hepatic carcinogenesis. J. Nutr. 141: 1049-1055, 2011.
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Foram avaliados dois protocolos de administração, em ratos sadios, de uma solução de fatores hepatotróficos (FH), composta por aminoácidos, vitaminas, sais minerais, glicose, insulina, glucagon e triiodotironina (T3). A solução foi administrada durante 10 dias, 40mg/kg/dia, i.p., em duas, grupo 2xFH (n=15), ou três doses, grupo 3xFH (n=15), diárias. Foram observados os efeitos na proliferação celular dos hepatócitos, na angiogênese e na matriz extracelular hepática, assim como as possíveis reações adversas. Os animais dos grupos 2xFH e 3xFH apresentaram aumento da massa hepática de 30,1% e 22,5%, respectivamente, em relação ao grupo-controle (CT; n=15). O índice de proliferação hepatocelular foi maior nos grupos 2xFH (1,4%) e 3xFH (1,2%) em relação ao grupo CT (0,53%), e a densitometria relativa do fator de crescimento do endotélio vascular pelo imunoblot não revelou diferença estatística entre os três grupos. Nos grupos 2xFH e 3xFH, houve redução do colágeno intersticial em relação ao grupo CT. A solução de FH estimulou o crescimento hepático e reduziu o volume de colágeno perissinusoidal. A administração em três doses diárias resultou em mortalidade de 26,7%, possivelmente pelo excessivo estresse da manipulação e pela menor adaptação fisiológica dos ratos, o que não ocorreu nos grupos 2xFH e CT. Para esse tipo de abordagem em ratos, o procedimento experimental mais apropriado, seguro, com melhor chance de adaptação dos animais e com resultados significativos é a aplicação dos FH em duas doses diárias.
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This study aimed to investigate the effects of physical training, and different levels of protein intake in the diet, on the growth and nutritional status of growing rats. Newly-weaned Wistar rats (n=48) were distributed into six experimental groups: three of them were subjected to physical swim training (1 h per day. 5 d per week, for 4 wk, after 2 wk of familiarization) and the other three were considered as controls (non-trained). Each pair of groups, trained and non-trained, received diets with a different level of protein in their composition: 14%. 21% or 28%. The animals were euthanized at the end of the training period and the following analyses were performed: proteoglycan synthesis as a biomarker of bone and cartilage growth, IGF-I (insulin-like growth factor-I) assay as a biomarker of growth and nutritional status. total RNA and protein concentration and protein synthesis measured in vivo using a large-dose phenylalanine method. As a main finding, increased dietary protein, combined with physical training, was able to improve neither tissue protein synthesis nor muscle growth. In addition, cartilage and bone growth seem to be deteriorated by the lower and the higher levels of protein intake. Our data allow us to conclude that protein enhancement in the diet, combined with physical exercise, does not stimulate tissue protein synthesis or muscle mass growth. Furthermore, physical training, combined with low protein intake, was not favorable to bone development in growing animals
Resumo:
This study aimed to investigate the effects of physical training, and different levels of protein intake in the diet, on the growth and nutritional status of growing rats. Newly-weaned Wistar rats (n=48) were distributed into six experimental groups: three of them were subjected to physical swim training (1 h per day. 5 d per week, for 4 wk, after 2 wk of familiarization) and the other three were considered as controls (non-trained). Each pair of groups, trained and non-trained, received diets with a different level of protein in their composition: 14%. 21% or 28%. The animals were euthanized at the end of the training period and the following analyses were performed: proteoglycan synthesis as a biomarker of bone and cartilage growth, IGF-I (insulin-like growth factor-I) assay as a biomarker of growth and nutritional status. total RNA and protein concentration and protein synthesis measured in vivo using a large-dose phenylalanine method. As a main finding, increased dietary protein, combined with physical training, was able to improve neither tissue protein synthesis nor muscle growth. In addition, cartilage and bone growth seem to be deteriorated by the lower and the higher levels of protein intake. Our data allow us to conclude that protein enhancement in the diet, combined with physical exercise, does not stimulate tissue protein synthesis or muscle mass growth. Furthermore, physical training, combined with low protein intake, was not favorable to bone development in growing animals.
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Background: Statins induces cell cycle arrest, apoptosis, reduction of angiogenic factors, inhibition of the endothelial growth factor, impairing tissue adhesion and attenuation of the resistance mechanisms. The aim of this study was evaluate the anti tumoral activity of simvastatin in a B16F10 melanoma-mouse model. Methods: Melanoma cells were treated with different concentrations of simvastatin and assessed by viability methods. Melanoma cells (5 x 10(4)) were implanted in two month old C57Bl6/J mice. Around 7 days after cells injection, the oral treatments were started with simvastatin (5 mg/kg/day, p.o.). Tumor size, hematological and biochemical analyses were evaluated. Results: Simvastatin at a concentration of 0.8 mu M, 1.2 mu M and 1.6 mu M had toxic effect. Concentration of 1.6 mu M induced a massive death in the first 24 h of incubation. Simvastatin at 0.8 mu M induces early cell cycle arrest in G0/G1, followed by increase of hypodiploidy. Tumor size were evaluated and the difference of treated group and control, after ten days, demonstrates that simvastatin inhibited the tumor expansion in 68%. Conclusion: Simvastatin at 1.6 mu M, presented cytototoxicity after 72 h of treatment, with an intense death. In vivo, simvastatin being potentially useful as an antiproliferative drug, with an impairment of growth after ten days.
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Objective-Nitro-fatty acids (NO(2)-FAs) are emerging as a new class of cell signaling mediators. Because NO(2)-FAs are found in the vascular compartment and their impact on vascularization remains unknown, we aimed to investigate the role of NO(2)-FAs in angiogenesis. Methods and Results-The effects of nitrolinoleic acid and nitrooleic acid were evaluated on migration of endothelial cell (EC) in vitro, EC sprouting ex vivo, and angiogenesis in the chorioallantoic membrane assay in vivo. At 10 mu mol/L, both NO(2)-FAs induced EC migration and the formation of sprouts and promoted angiogenesis in vivo in an NO-dependent manner. In addition, NO(2)-FAs increased intracellular NO concentration, upregulated protein expression of the hypoxia inducible factor-1 alpha (HIF-1 alpha) transcription factor by an NO-mediated mechanism, and induced expression of HIF-1 alpha target genes, such as vascular endothelial growth factor, glucose transporter-1, and adrenomedullin. Compared with typical NO donors such as spermine-NONOate and deta-NONOate, NO(2)-FAs were slightly less potent inducers of EC migration and HIF-1 alpha expression. Short hairpin RNA-mediated knockdown of HIF-1 alpha attenuated the induction of vascular endothelial growth factor mRNA expression and EC migration stimulated by NO(2)-FAs. Conclusion-Our data disclose a novel physiological role for NO(2)-FAs, indicating that these compounds induce angiogenesis in an NO-dependent mechanism via activation of HIF-1 alpha. (Arterioscler Thromb Vasc Biol. 2011;31:1360-1367.)
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Stromal cells from pediatric myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) associated with MDS(MDS-AML) present high expression of leukemia inhibitor factor (LIF). We demonstrated using mitogen-activated protein kinase ( MAPK) inhibitors that in stromal cells from pediatric MDS and MDS-AML, p38MAPK was critical in serum-induced secretion of LIF. The serum induction of phosphorylated p38MAPK form was observed only in stromal cells from healthy children, whereas in MDS and MDS-AML basal levels were maintained suggesting constitutive p38MAPK activation. Our study suggested the possible importance in pediatric MDS of p38MAPK signaling pathway which may be a future therapeutic target. (C) 2009 Elsevier Ltd. All rights reserved.
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Our data suggest that serum concentrations of insulin-like growth factor I and insulin-like growth factor binding protein 3 do not correlate with breast cancer development. (Fertil Steril (R) 2011;95:2753-5. (C)2011 by American Society for Reproductive Medicine.)
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Objective: To analyze the antiangiogenic effects of the selective cyclooxygenase-2 (COX-2) inhibitor parecoxib on the growth of endometrial implants in a rat model of peritoneal endometriosis. Design: Pharmacologic interventions in an experimental model of peritoneal endometriosis. Setting: Research laboratory in the Federal University of Rio de Janeiro. Animal(s): Twenty female Sprague-Dawley rats with experimentally induced endometriosis. Intervention(s): After implantation and establishment of autologous endometrium onto the peritoneum abdominal wall, rats were randomized into groups and treated with parecoxib or the vehicle by IM injection for 30 days. Main Outcome Measure(s): Vascular density, the expression of vascular endothelial growth factor (VEGF) and its receptor Flk-1, the distribution of activated macrophages, the expression of COX-2, and the prostaglandin concentration in the endometriotic lesions treated with parecoxib were analyzed. Result(s): The treatment significantly decreased the implant size, and histologic examination indicated mostly atrophy and regression. A reduction in microvessel density and in the number of macrophages, associated with decreased expression of VEGF and Flk-1, also were observed. The treatment group showed a low concentration of prostaglandin E(2). Conclusion(s): These results suggest that the use of COX-2 selective inhibitors could be effective to suppress the establishment and growth of endometriosis, partially through their antiangiogenic activity. (Fertil Steril (R) 2010; 93: 2674-9. (C) 2010 by American Society for Reproductive Medicine.)
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Brain-derived neurotrophic factor (BDNF) is the most widely distributed neurotrophin in the CNS, where it plays several pivotal roles in synaptic plasticity and neuronal survival. As a consequence, BDNF has become a key target in the physiopathology of several neurological and psychiatric diseases. Recent studies have consistently reported altered levels of BDNF in the circulation (i.e., serum or plasma) of patients with major depression, bipolar disorder, Alzheimer`s disease, Huntington`s disease and Parkinson`s disease. Correlations between serum BDNF levels and affective, cognitive and motor symptoms have also been described. BDNF appears to be an unspecific biomarker of neuropsychiatric disorders characterized by neurodegenerative changes.
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Background/Aims: There are many controversies regarding side effects on craniofacial and extremity growth due to growth hormone ( GH) treatment. Our aim was to estimate GH action on craniofacial development and extremity growth in GH-deficient patients. Methods: Twenty patients with GH deficiency with a chronological age ranging from 4.6 to 24.3 years (bone age from 1.5 to 13 years) were divided in 2 groups: group 1 (n = 6), naive to GH treatment, and group 2 (n = 14), ongoing GH treatment for 2-11 years. GH doses (0.1 -0.15 U/kg/day) were adjusted to maintain insulin-like growth factor 1 and insulin-like growth factor binding protein 3 levels within the normal range. Anthropometric measurements, cephalometric analyses and facial photographs to verify profile and harmony were performed annually for at least 3 years. Results: Two patients with a disharmonious profile due to mandibular growth attained harmony, and none of them developed facial disharmony. Increased hand or foot size (>P97) was observed in 2 female patients and in 4 patients (1 female), respectively, both not correlated with GH treatment duration and increased levels of insulin-like growth factor 1. Conclusions: GH treatment with standard doses in GH-deficient patients can improve the facial profile in retrognathic patients and does not lead to facial disharmony although extremity growth, mainly involving the feet, can occur. Copyright (C) 2009 S. Karger AG, Basel