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1.
Chinese Journal of Contemporary Pediatrics ; (12): 1143-1149, 2023.
Artículo en Chino | WPRIM | ID: wpr-1009861

RESUMEN

OBJECTIVES@#To investigate the changes in the serum levels of Klotho, fibroblast growth factor 23 (FGF23), and insulin-like growth factor-1 (IGF-1) in children with idiopathic short stature (ISS) before and after recombinant human growth hormone (rhGH) treatment, as well as the correlation of Klotho and FGF23 with the growth hormone (GH)/IGF-1 growth axis in these children.@*METHODS@#A prospective study was conducted on 33 children who were diagnosed with ISS in the Department of Pediatrics, Hebei Provincial People's Hospital, from March 10, 2021 to December 1, 2022 (ISS group). Twenty-nine healthy children, matched for age and sex, who attended the Department of Child Healthcare during the same period, were enrolled as the healthy control group. The children in the ISS group were treated with rhGH, and the serum levels of Klotho, FGF23, and IGF-1 were measured before treatment and after 3, 6, and 9 months of treatment. A correlation analysis was conducted on these indexes.@*RESULTS@#There were no significant differences in the serum levels of IGF-1, Klotho, and FGF23 between the ISS and healthy control groups (P>0.05). The serum levels of Klotho, FGF23, and IGF-1 increased significantly in the ISS group after 3, 6, and 9 months of rhGH treatment (P<0.05). In the ISS group, Klotho and FGF23 levels were positively correlated with the phosphate level before treatment (P<0.05). Before treatment and after 3, 6, and 9 months of rhGH treatment, the Klotho level was positively correlated with the IGF-1 level (P<0.05), the FGF23 level was positively correlated with the IGF-1 level (P<0.05), and the Klotho level was positively correlated with the FGF23 level (P<0.05), while Klotho and FGF23 levels were not correlated with the height standard deviation of point (P>0.05).@*CONCLUSIONS@#The rhGH treatment can upregulate the levels of Klotho, FGF23, and IGF-1 and realize the catch-up growth in children with ISS. Klotho and FGF23 may not directly promote the linear growth of children with ISS, but may have indirect effects through the pathways such as IGF-1 and phosphate metabolism. The consistent changes in Klotho, FGF23 and IGF-1 levels show that there is a synergistic relationship among them in regulating the linear growth of ISS children.


Asunto(s)
Niño , Humanos , Hormona de Crecimiento Humana/farmacología , Factor I del Crecimiento Similar a la Insulina/farmacología , Factor-23 de Crecimiento de Fibroblastos , Estudios Prospectivos , Trastornos del Crecimiento , Fosfatos/farmacología , Estatura
2.
China Journal of Chinese Materia Medica ; (24): 5250-5258, 2023.
Artículo en Chino | WPRIM | ID: wpr-1008722

RESUMEN

To explore the effect and mechanism of Zuogui Pills in promoting neural tissue recovery and functional recovery in mice with ischemic stroke. Male C57BL/6J mice were randomly divided into a sham group, a model group, and low-, medium, and high-dose Zuogui Pills groups(3.5, 7, and 14 g·kg~(-1)), with 15 mice in each group. The ischemic stroke model was established using photochemical embolization. Stiker remove and irregular ladder walking behavioral tests were conducted before modeling and on days 7, 14, 21, and 28 after medication. Triphenyl tetrazolium chloride(TTC) staining was performed on day 3 after modeling, and T2-weighted imaging(T2WI) and diffusion-weighted imaging(DWI) were performed on day 28 after medication to evaluate the extent of brain injury. Hematoxylin-eosin(HE) staining was performed to observe the histology of the cerebral cortex. Axonal marker proteins myelin basic protein(MBP), growth-associated protein 43(GAP43), mammalian target of rapamycin(mTOR), and its downstream phosphorylated s6 ribosomal protein(p-S6), as well as mechanism-related proteins osteopontin(OPN) and insulin-like growth factor 1(IGF-1), were detected using immunofluorescence and Western blot. Zuogui Pills had a certain restorative effect on the neural function impairment caused by ischemic stroke in mice. TTC staining showed white infarct foci in the sensory-motor cortex area, and T2WI imaging revealed cystic necrosis in the sensory-motor cortex area. The Zuogui Pills groups showed less brain tissue damage, fewer scars, and more capillaries. The number of neuronal axons in those groups was higher than that in the model group, and neuronal activity was stronger. The expression of GAP43, OPN, IGF-1, and mTOR proteins in the Zuogui Pills groups was higher than that in the model group. In summary, Zuogui Pills can promote the recovery of neural function and axonal growth in mice with ischemic stroke, and its mechanism may be related to the activation of the OPN/IGF-1/mTOR signaling pathway.


Asunto(s)
Ratones , Animales , Masculino , Accidente Cerebrovascular Isquémico , Recuperación de la Función/fisiología , Factor I del Crecimiento Similar a la Insulina/farmacología , Ratones Endogámicos C57BL , Serina-Treonina Quinasas TOR/metabolismo , Accidente Cerebrovascular/tratamiento farmacológico , Isquemia Encefálica/tratamiento farmacológico , Mamíferos/metabolismo
3.
Acta cir. bras ; 31(8): 513-519, Aug. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-792411

RESUMEN

ABSTRACT PURPOSE: To investigate the effects of pharmacological delay with insulin-like growth factor-1 (IGF-1) on skin flap survival. METHODS: Thirty Sprague-Dawley rats were submitted to dorsal skin flap (3x9 cm). Seven days before the surgery, the animals were subdivided into three groups of 10 rats. In group 1 (controls), no injection was done. Seven days before the elevation, saline had been injected to the marked skin flap area in group 2 (sham group), and group 3 (experimental group) underwent a pharmacological delay with subcutaneous IGF-1 injections. On the seventh postoperative day, flap area was analyzed for survival. Tissue samples were obtained for histological and biochemical evaluations. RESULTS: Survival rates were 43.55 ± 16%, 21.40 ± 8%, and 43.12 ± 14% in groups 1, 2, and 3, respectively. Differences between group 2 and other groups were statistically significant. No significant difference was detected between all three groups for tissue or plasma vascular endothelial growth factor (VEGF) levels. There was no significant histological difference between groups. CONCLUSION: Although a single injection of insulin-like growth factor-1 (IGF-1) did not significantly increase flap survival, its wound healing features are still encouraging and further meticulously planned studies, especially with repeated applications or controlled-release methods, and combinations with binding protein are required.


Asunto(s)
Animales , Ratas , Colgajos Quirúrgicos/fisiología , Cicatrización de Heridas/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/farmacología , Supervivencia de Injerto/efectos de los fármacos , Antiinflamatorios/farmacología , Colgajos Quirúrgicos/irrigación sanguínea , Factor I del Crecimiento Similar a la Insulina/administración & dosificación , Ratas Sprague-Dawley , Factores de Crecimiento Endotelial Vascular/sangre , Inyecciones Subcutáneas , Antiinflamatorios/administración & dosificación
4.
Braz. dent. j ; 24(4): 299-307, July-Aug/2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-689828

RESUMEN

This work evaluated the bone-forming potential of the platelet-derived growth factor isoform BB (PDGF-BB), insulin-like growth factor I (IGF-I), and mixed PDGF-BB/IGF-I delivered in liposomes compared with phosphate buffered saline (PBS), in the healing process of rat tooth sockets. One hundred and twelve Wistar rats were randomized into 7 groups of 16 animals each and were evaluated at 3, 7, 14 and 21 days after extraction of the maxillary second molars. The left sockets were treated with PBS (P), empty liposome (L), IGF-I in PBS (IP), IGF-I in liposome (IL), PDGF-BB in PBS (PDP), PDGF-BB in liposome (PDL) and both growth factors (GFs) together within liposomes (PDIL). The right sockets were filled with blood clot (BC). Histological and histomorphometric analyses were used to evaluate the formation of new bone and blood vessels. Immunohistochemistry was performed to evaluate the expression of osteocalcin and vascular endothelial growth factor (VEGF) during bone repair. Data were tested statistically using a Tukey's test according to a Dunn's analysis and Mann-Whitney U test followed by Kruskal-Wallis one-way analysis. Results were considered significant when p<0.05. A significantly higher percentage of bone trabeculae and a higher number of blood vessels were observed in the IL, PDL and PDIL groups (p<0.05). However, these GF-liposome groups had statistically similar results. Immunohistochemical assays first detected osteocalcin and VEGF expression at 3 days followed by a peak at 7 days. Lower immunoreactivity levels were observed in the BC, L, P, IP and PDP groups compared with the IL, PDL and PDIL groups (p<0.05). The results suggest that GFs carried by liposomes, either in isolated or mixed forms, enhanced the healing process in rat tooth sockets. The differential expression of the osteogenic markers VEGF and osteocalcin in the early phases of bone healing support these findings.


Este trabalho avaliou o potencial de formação óssea do fator de crescimento derivado de plaquetas na isoforma BB (PDGF-BB), fator de crescimento semelhante à insulina I (IGF-I), e a mistura PDGF-BB/IGF-I administrada em lipossomas comparando com tampão fosfato salino (PBS), no processo de cicatrização de alvéolos dentários de ratos. Cento e doze ratos Wistar foram distribuídos aleatoriamente em 7 grupos de 16 animais cada e foram avaliados aos 3, 7, 14 e 21 dias após a extração dos segundos molares maxilares. Os alvéolos esquerdos foram tratados com PBS (P), lipossomas vazios (L), IGF-I em PBS (IP), IGF-I em lipossomas (IL), PDGF-BB em PBS (PDP), PDGF-BB em lipossomas (PDL) e ambos os fatores de crescimento (GFs) em associação dentro de lipossomas (PDIL). Os alvéolos direitos foram preenchidos com coágulo sanguíneo (BC). As análises histomorfométrica e histológica foram utilizadas para avaliar a formação de novo osso e vasos sanguíneos. Imunohistoquímica foi realizada para avaliar a expressão de osteocalcina e o fator de crescimento endotelial vascular (VEGF) durante o reparo ósseo. Os dados foram testados estatisticamente utilizando o teste de Tukey em acordo com análise de Dunn e o teste Mann-Whitney U seguido pela análise de um passo de Kruskal-Wallis. Os resultados foram considerados significantes quando p<0,05. Uma percentagem altamente significativa de osso trabecular e alto número de vasos sanguíneos foram observados nos grupos IL, PDL e PDIL (p<0,05). Todavia, esses grupos lipossoma-GF tiveram resultados similares estatisticamente. Ensaios de imunohistoquímica inicialmente detectaram a expressão de osteocalcina e VEGF aos 3 dias, seguida por um pico aos 7 dias. Niveis mais baixos de imunorreatividade foram observados em BC, L, P, PI e PDP quando comparados com os grupos IL, PDL e PDIL (p<0,05). Os resultados sugerem que GFs carreados por lipossomas, na forma isolada ou em combinação, aceleram o processo de cicatrização em alvéolos dentários de rato. A expressão diferencial dos marcadores osteogênicos VEGF e osteocalcina, nas fases iniciais de cicatrização óssea, confirma esses achados.


Asunto(s)
Animales , Masculino , Ratas , Factor I del Crecimiento Similar a la Insulina/administración & dosificación , Liposomas , Proteínas Proto-Oncogénicas c-sis/administración & dosificación , Alveolo Dental/patología , Cicatrización de Heridas/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/farmacología , Proteínas Proto-Oncogénicas c-sis/farmacología , Ratas Wistar
5.
Clinics ; 67(1): 35-40, 2012. ilus
Artículo en Inglés | LILACS | ID: lil-610621

RESUMEN

OBJECTIVE: Hypoxia-inducible factor 1 alpha regulates genes related to cellular survival under hypoxia. This factor is present in osteroarthritic chondrocytes, and cytokines, such as interleukin-1 beta, participate in the pathogenesis of osteoarthritis, thereby increasing the activities of proteolytic enzymes, such as matrix metalloproteinases, and accelerating cartilage destruction. We hypothesize that Hypoxia Inducible Factor-1 alpha (HIF-1α) can regulate cytokines (catabolic action) and/or growth factors (anabolic action) in osteoarthritis. The purpose of this study was to investigate the modulation of HIF-1α in human osteoarthritic chondrocytes by interleukin-1 beta (IL-1β) and insulin-like growth factors I (IGF-I) and II (IGF-II) and to determine the involvement of the phosphatidylinositol-3kinase (PI-3K) pathway in this process. METHODS: Human osteroarthritic chondrocytes were stimulated with IL-1β, IGF-I and IGF-II and LY294002, a specific inhibitor of PI-3K. Nuclear protein levels and gene expression were analyzed by western blot and quantitative reverse transcription-polymerase chain reaction analyses, respectively. RESULTS: HIF-1α expression was upregulated by IL-1β at the protein level but not at the gene level. IGF-I treatment resulted in increases in both the protein and mRNA levels of HIF-1α , whereas IGF-II had no effect on its expression. However, all of these stimuli exploited the PI-3K pathway. CONCLUSION: IL-1β upregulated the levels of HIF-1α protein post-transcriptionally, whereas IGF-I increased HIF-1α at the transcript level. In contrast, IGF-II did not affect the protein or gene expression levels of HIF-1α . Furthermore, all of the tested stimuli exploited the PI-3K pathway to some degree. Based on these findings, we are able to suggest that Hypoxia inducible Factor-1 exhibits protective activity in chondrocytes during osteoarthritis.


Asunto(s)
Humanos , Condrocitos/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Factor II del Crecimiento Similar a la Insulina/farmacología , Interleucina-1beta/farmacología , Osteoartritis/metabolismo , Condrocitos/metabolismo , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Osteoartritis/genética , /antagonistas & inhibidores , /metabolismo , ARN Mensajero/análisis , Estadísticas no Paramétricas , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética
6.
Braz. j. med. biol. res ; 44(12): 1194-1201, Dec. 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-606537

RESUMEN

Recent biotechnological advances have permitted the manipulation of genetic sequences to treat several diseases in a process called gene therapy. However, the advance of gene therapy has opened the door to the possibility of using genetic manipulation (GM) to enhance athletic performance. In such ‘gene doping’, exogenous genetic sequences are inserted into a specific tissue, altering cellular gene activity or leading to the expression of a protein product. The exogenous genes most likely to be utilized for gene doping include erythropoietin (EPO), vascular endothelial growth factor (VEGF), insulin-like growth factor type 1 (IGF-1), myostatin antagonists, and endorphin. However, many other genes could also be used, such as those involved in glucose metabolic pathways. Because gene doping would be very difficult to detect, it is inherently very attractive for those involved in sports who are prepared to cheat. Moreover, the field of gene therapy is constantly and rapidly progressing, and this is likely to generate many new possibilities for gene doping. Thus, as part of the general fight against all forms of doping, it will be necessary to develop and continually improve means of detecting exogenous gene sequences (or their products) in athletes. Nevertheless, some bioethicists have argued for a liberal approach to gene doping.


Asunto(s)
Humanos , Rendimiento Atlético , Doping en los Deportes/métodos , Técnicas de Transferencia de Gen , Mejoramiento Genético/métodos , Discusiones Bioéticas , Doping en los Deportes , Endorfinas/genética , Endorfinas/farmacología , Eritropoyetina/genética , Eritropoyetina/farmacología , Mejoramiento Genético , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/farmacología , Miostatina/genética , Miostatina/farmacología , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/farmacología
7.
Braz. j. med. biol. res ; 43(8): 728-736, Aug. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-554966

RESUMEN

The objective of this study was to determine the effects of GDF-9, IGF-I, and GH alone or combined on preantral follicle survival, activation and development after 1 and 7 days of in vitro culture. Either fresh (non-cultured) or cultured ovarian tissue was processed for histological and fluorescence analysis. For all media tested, the percent of normal follicles was greater when compared to minimum essential medium supplemented (MEM+) alone, except when ovarian tissue was cultured with GDF-9/IGF-I or GDF-9/GH (P < 0.05). Fluorescence analysis showed that the percent of viable follicles after 7 days of culture was similar for non-cultured tissue and for all treatments tested. The percent of primordial follicles was reduced (P < 0.05) and there was a significant and concomitant increase in the percent of intermediate and primary follicles in all treatments tested after 7 days of culture when compared to non-cultured tissue. After 7 days of culture, the highest percent of intermediate follicles was observed with IGF-I/GH (61.3 percent), and the highest percent of primary follicles was achieved with IGF-I (57.7 percent). After 7 days of culture in MEM+ containing GDF-9, IGF-I and GH alone or in all associations, a significant increase in follicular diameter was observed when compared to MEM+ alone and non-cultured tissue. In conclusion, GDF-9, IGF-I and GH alone or in combination maintain preantral follicle survival and promote primordial follicle activation. Nevertheless, the data showed that IGF-I/GH and IGF-I alone are efficient in promoting the transition from primordial to intermediate follicles and from intermediate to primary follicles, respectively.


Asunto(s)
Animales , Femenino , Factor 9 de Diferenciación de Crecimiento/farmacología , Hormona del Crecimiento/farmacología , Factor I del Crecimiento Similar a la Insulina/farmacología , Folículo Ovárico/efectos de los fármacos , Proliferación Celular , Cabras , Microscopía Fluorescente , Folículo Ovárico/citología , Folículo Ovárico/crecimiento & desarrollo , Técnicas de Cultivo de Tejidos
8.
Experimental & Molecular Medicine ; : 696-702, 2010.
Artículo en Inglés | WPRIM | ID: wpr-193634

RESUMEN

Expression of zinc-finger protein 143 (ZNF143), a human homolog of the Xenopus transcriptional activator protein Staf, is induced by various DNA-damaging agents including etoposide, doxorubicin, and gamma-irradiation. ZNF143 binds to cisplatin-modified DNA, and its levels are increased in cancer cells that are resistant to anticancer drugs, including cisplatin, suggesting that it plays a role in carcinogenesis and cancer cell survival. However, the mechanism of ZNF143 induction in cancer cells remains unclear. Both insulin-like growth factor-1 (IGF-1) and its receptor (IGF-1R) have been reported to be overexpressed in cancer cells and to be related to anticancer drug resistance, but the identity of the relevant signaling mediators is still being investigated. In the present study, we observed that IGF-1 was able to induce ZNF143 expression in HCT116 human colon cancer cells and that wortmannin, an inhibitor of phosphatidylinositide 3-kinase (PI3-kinase), inhibited this induction, as did diphenyleneiodonium (DPI), an NADPH oxidase inhibitor, and monodansylcardavarine (MDC), a receptor internalization inhibitor. Treatment with MDC decreased the IGF-1-stimulated generation of reactive oxygen species. Taken together, these data suggest that IGF-1 induces ZNF143 expression in cancer cells via PI3-kinase and reactive oxygen species generation during receptor internalization.


Asunto(s)
Humanos , Antineoplásicos/farmacología , Línea Celular Tumoral , Cisplatino/farmacología , Neoplasias del Colon/enzimología , Células HCT116 , Factor I del Crecimiento Similar a la Insulina/farmacología , Fosfatidilinositol 3-Quinasa/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Transactivadores/biosíntesis
9.
Indian J Exp Biol ; 2007 Aug; 45(8): 669-75
Artículo en Inglés | IMSEAR | ID: sea-60809

RESUMEN

The tumor necrosis factor-alpha (TNF-alpha) plays an important role in ovarian follicular development and ovulation process and acts through its receptor (TNFRI). The present investigation describes the expression of mRNAs encoding TNF-alpha and TNFRI in relation to glyceraldehyde-3-phosphate dehydrogenase (G3PDH) and beta-actin as control genes, using RT-PCR, in granulosa cells, intact follicles and luteal tissues from buffalo ovary. There was significant higher expression of mRNAs encoding TNF-alpha in granulosa cells from medium follicles and TNFRI expression increased with increase in size of follicles. Post-ovulatory structures (corpus luteum and corpus albicans) exhibited significantly higher expression of TNFRI mRNAs as compared to that obtained in intact follicles suggesting its immediate and critical role just after ovulation, for mediating TNF-alpha action on these tissues. Though the expression of TNF-alpha mRNA was stimulated by treatment of granulosa cells with FSH during culture, the expression of TNFRI mRNA did not change. The FSH alongwith IGF-I did not exert any effect. These results suggested an important role of TNF-alpha and its receptor in buffalo ovarian functions.


Asunto(s)
Actinas/genética , Animales , Búfalos/crecimiento & desarrollo , Cuerpo Lúteo/metabolismo , Femenino , Hormona Folículo Estimulante/farmacología , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Células de la Granulosa/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/farmacología , Folículo Ovárico/efectos de los fármacos , Ovario/efectos de los fármacos , ARN Mensajero/análisis , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Factor de Necrosis Tumoral alfa/genética
10.
Yonsei Medical Journal ; : 949-954, 2007.
Artículo en Inglés | WPRIM | ID: wpr-154658

RESUMEN

PURPOSE: To determine whether insulin-like growth factor (IGF-1) affects transforming growth factor (TGF-beta)- mediated fibronectin accumulation in human lens epithelial cell line (HLE B-3) cells. MATERIALS AND METHODS: HLE B-3 cells were incubated for 24 hours with TGF-beta (10ng/ mL), IGF-1 (10ng/mL), or both. Expression of the fibronectin gene was determined using a real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Fibronectin levels were examined using western blot analysis and immunofluorescence staining. RESULTS: Expression of the fibronectin gene was not different between the TGF-beta/IGF-1 treated group and the TGF-beta treated group (p= 0.116). However, western blot analysis demonstrated decreased fibronectin levels in human lens epithelial cells treated with TGF-beta and IGF-1 compared to those treated with TGF-beta only (p < 0.01). Immunofluorescence staining disclosed inhibition of TGF-beta-induced fibronectin in the presence of IGF-1. CONCLUSION: This study suggests that IGF-1 counteracts TGF-beta-mediated fibronectin accumulation in human lens epithelial cells.


Asunto(s)
Humanos , Línea Celular , Células Epiteliales/citología , Fibronectinas/genética , Técnica del Anticuerpo Fluorescente , Regulación de la Expresión Génica/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/farmacología , Cristalino/citología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Crecimiento Transformador beta/farmacología
11.
Jordan Medical Journal. 2006; 40 (4): 300-314
en Inglés | IMEMR | ID: emr-77652

RESUMEN

IGF-1 that is generated in the liver is the anabolic effector and linear growth promoting hormone of the pituitary Growth Hormone [GH]. In the tissues, IGFs are important regulators of cell survival, growth, metabolism and differentiated functions. Prospective studies suggest that individuals with circulating levels of Insulin- like Growth Factor 1 [IGF-1] at the high end of the normal range are exposed to increased risk for several common cancers. This has led to the development of novel IGF- I receptor targeting therapies which have impressive antineoplastic activity in experimental system. This review article will focus on the biology of IGF-1 and its role in health and malignant states


Asunto(s)
Humanos , Factor II del Crecimiento Similar a la Insulina/fisiología , Factor I del Crecimiento Similar a la Insulina/farmacología , Factor II del Crecimiento Similar a la Insulina/farmacología , Hormona del Crecimiento , Receptor IGF Tipo 1 , Trastornos del Crecimiento
12.
Biol. Res ; 37(4): 625-633, 2004. tab, graf
Artículo en Inglés | LILACS | ID: lil-437518

RESUMEN

We studied the effect of IGF-I, insulin and testosterone on intracellular Ca2+ in cultured muscle cells. Insulin produced a fast (<1 s) and transient [Ca2+] increase lasting less than 10 s. IGF-I induced a transient [Ca2+] increase, reaching a fluorescence peak 6 s after stimulus, to return to basal values after 60 s. Testosterone induced delayed (35 s) and long lasting (100-200 s) signals, frequently associated with oscillations. IGF-I, testosterone and electrical stimulation-induced Ca2+ signals were shown to be dependent on IP3 production. All of these Ca2+ signals were blocked by inhibitors of the IP3 pathway. On the other hand, insulin-induced Ca2+ increase was dependent on ryanodine receptors and blocked by either nifedipine or ryanodine. The different intracellular Ca2+ patterns produced by electrical stimulation, testosterone, IGF-I and insulin, may help to understand the role of intracellular calcium kinetics in the regulation of gene expression by various stimuli in skeletal muscle cells.


Asunto(s)
Animales , Ratas , Células Musculares , Células Musculares/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Insulina/farmacología , Señalización del Calcio , Señalización del Calcio/fisiología , Testosterona/farmacología , Técnicas de Cultivo de Célula , Calcio/metabolismo , Estimulación Eléctrica , Expresión Génica , Factores de Transcripción/metabolismo , Miocitos Cardíacos , Miocitos Cardíacos/metabolismo , Músculo Esquelético/citología , Músculo Esquelético , Potenciales de la Membrana
13.
J Biosci ; 2001 Sep; 26(3): 341-7
Artículo en Inglés | IMSEAR | ID: sea-110977

RESUMEN

Meiotic arrest of oocyte in an Indian carp, Labeo rohita Ham. has been found for the first time to be withdrawn by insulin only. Addition of insulin to oocytes in vitro caused germinal vesicle breakdown (GVBD), one of the first visual markers to determine initiation of the final maturational process. Under the influence of insulin the germinal vesicle (GV) of the oocyte migrated towards the animal pole, reached the micropyle and then dissolved (GVBD). By using different concentrations of insulin i.e., 0.063, 0.63, 6.3 and 12.6 mM, optimum amount required was found to be 6.3 mM. Induction of GVBD by insulin could be blocked by cycloheximide (Chx), a translation inhibitor, while actinomycin D (AcD) had no effect suggesting non-involvement of transcriptional activity in this process. Addition of the maturation-inducing steroid 17alpha,20beta-dihydroxy-4-pregnen-3-one (DHP) stimulated (P<0.01) GVBD of carp oocytes and its combination with insulin showed an additive effect. Gonadotropin (GtH) caused GVBD but its effect was greatly augmented by insulin. Our results demonstrate that not only can insulin alone induce GVBD in carp oocytes, but it also augments the stimulatory effect of DHP or IGF-I or GtH on GVBD. This information will be important in hormonal manipulation during induced breeding of carp.


Asunto(s)
Animales , Carpas/fisiología , Cicloheximida/farmacología , Dactinomicina/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Gonadotropinas/farmacología , Hidroxiprogesteronas/farmacología , Insulina/farmacología , Factor I del Crecimiento Similar a la Insulina/farmacología , Meiosis/fisiología , Oocitos/citología , Inhibidores de la Síntesis de la Proteína/farmacología
14.
Journal of Korean Medical Science ; : 155-163, 1995.
Artículo en Inglés | WPRIM | ID: wpr-7340

RESUMEN

This study was performed to prove the hypothesis that oncogene expressions would have the same patterns with those of cellular growth to growth factors in FRTL-5 cells. Ribonucleic acids of FRTL-5 were extracted at 15', 30', 60' and 120' after administration of growth factors to quiescent FRTL-5, and blotted to the nitrocellulose membrane. They were hybridized with radiolabelled c-fos, c-myc and beta-actin probes. Hybridized dot blots were autoradiographed and the amount of radioactivity was measured by densitometry. Densitometric readings were used as the indices of oncogene expressions. Expressions of c-fos and c-myc were more prominent in combined administrations of TSH (10 mU/ml) and IGF-I (100 ng/ml) or IgG of Graves' disease (Graves' IgG; 1 mg/ml) and IGF-I than in combined administration of TSH and Graves' IgG. IgG of primary myxedema suppressed oncogene expressions by TSH or Graves' IgG, but not by IGF-I. From the above results, it was suggested that expressions of c-fos and c-myc to growth factors would have similar patterns with those of cell growth to growth factors in FRTL-5, and the actions of TSH and Graves' IgG would be manifested through same signal transduction system, but IGF-I would be manifested by its own.


Asunto(s)
Ratas , Animales , División Celular/efectos de los fármacos , Línea Celular/citología , Expresión Génica/efectos de los fármacos , Enfermedad de Graves/inmunología , Sustancias de Crecimiento/genética , Inmunoglobulina G/farmacología , Factor I del Crecimiento Similar a la Insulina/farmacología , Mixedema/inmunología , Proteínas Proto-Oncogénicas c-fos/genética , Proteínas Proto-Oncogénicas c-myc/genética , ARN/análisis , Ratas Endogámicas F344 , Glándula Tiroides/citología , Tirotropina/farmacología , Factores de Tiempo
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