Evaluation of the anticonvulsant and neuroprotective effect of intracerebral administration of growth hormone in rats / Evaluación del efecto anticonvulsivante y neuroprotector de la administración intracerebral de la hormona de crecimiento en ratas

Introduction The growth hormone (GH) has been reported as a crucial neuronal survival factor in the hippocampus against insults of diverse nature. Status epilepticus (SE) is a prolonged seizure that produces extensive neuronal cell death. The goal of this study was to evaluate the effect of intracerebroventricular administration of GH on seizure severity and SE-induced hippocampal neurodegeneration. Methodology Adult male rats were implanted with a guide cannula in the left ventricle and different amounts of GH (70, 120 or 220 ng/3 μl) were microinjected for 5 days; artificial cerebrospinal fluid was used as the vehicle. Seizures were induced by the lithium–pilocarpine model (3 mEq/kg LiCl and 30 mg/kg pilocarpine hydrochloride) one day after the last GH administration. Neuronal injury was assessed by Fluoro-Jade B (F-JB) staining. Results Rats injected with 120 ng of GH did not had SE after 30 mg/kg pilocarpine, they required a higher number of pilocarpine injections to develop SE than the rats pretreated with the vehicle, 70 ng or 220 ng GH. Prefrontal and parietal cortex EEG recordings confirmed that latency to generalized seizures and SE was also significantly higher in the 120 ng group when compared with all the experimental groups. FJ-B positive cells were detected in the hippocampus after SE in all rats, and no significant differences in the number of F-JB cells in the CA1 area and the hilus was observed between experimental groups. Conclusion Our results indicate that, although GH has an anticonvulsive effect in the lithium–pilocarpine model of SE, it does not exert hippocampal neuroprotection after SE. (AU)

Introducción La hormona de crecimiento (HC) es un factor que favorece la supervivencia neuronal en el hipocampo ante agresiones de diversa naturaleza. El status epilepticus (SE) es un tipo de crisis epiléptica de larga duración que produce muerte neuronal. El objetivo de este estudio fue evaluar el efecto de la administración intracerebroventricular de HC en la severidad de las convulsiones y la neurodegeneración hipocampal debida al SE. Metodología A ratas macho adultas se les implantó una cánula guía en el ventrículo lateral izquierdo y se les microinyectaron diferentes cantidades de HC (70, 120 o 220 ng/3 μl) durante 5 días; como vehículo se inyectó líquido cefalorraquídeo artificial. Las convulsiones se generaron con el modelo de litio-pilocarpina (3 mEq/kg LiCl y 30 mg/kg clorhidrato pilocarpina) un día después de la última inyección de HC. La neurodegeneración se identificó con la tinción de Fluoro-Jade B (F-JB). Resultados Las ratas a las que se les inyectaron 120 ng de HC requirieron 2 o 3 inyecciones de pilocarpina para desarrollar SE, en comparación con el resto de los grupos experimentales que requirieron solo una aplicación del convulsivante. Los registros EEG de la corteza prefrontal y parietal confirmaron que la latencia a las crisis generalizadas y al SE fue mayor en dicho grupo experimental. Todas las ratas con SE presentaron células positivas al FJ-B en el área CA1 e hilus del hipocampo, y no se identificaron diferencias entre los tratamientos. Conclusión Nuestros resultados muestran que, aunque la HC tiene un efecto anticonvulsivante, una vez que se ha desarrollado el SE no promueve neuroprotección en el hipocampo. (AU)

Evaluation of the anticonvulsant and neuroprotective effect of intracerebral administration of growth hormone in rats / Evaluación del efecto anticonvulsivante y neuroprotector de la administración intracerebral de la hormona de crecimiento en ratas

Introduction The growth hormone (GH) has been reported as a crucial neuronal survival factor in the hippocampus against insults of diverse nature. Status epilepticus (SE) is a prolonged seizure that produces extensive neuronal cell death. The goal of this study was to evaluate the effect of intracerebroventricular administration of GH on seizure severity and SE-induced hippocampal neurodegeneration. Methodology Adult male rats were implanted with a guide cannula in the left ventricle and different amounts of GH (70, 120 or 220 ng/3 μl) were microinjected for 5 days; artificial cerebrospinal fluid was used as the vehicle. Seizures were induced by the lithium–pilocarpine model (3 mEq/kg LiCl and 30 mg/kg pilocarpine hydrochloride) one day after the last GH administration. Neuronal injury was assessed by Fluoro-Jade B (F-JB) staining. Results Rats injected with 120 ng of GH did not had SE after 30 mg/kg pilocarpine, they required a higher number of pilocarpine injections to develop SE than the rats pretreated with the vehicle, 70 ng or 220 ng GH. Prefrontal and parietal cortex EEG recordings confirmed that latency to generalized seizures and SE was also significantly higher in the 120 ng group when compared with all the experimental groups. FJ-B positive cells were detected in the hippocampus after SE in all rats, and no significant differences in the number of F-JB cells in the CA1 area and the hilus was observed between experimental groups. Conclusion Our results indicate that, although GH has an anticonvulsive effect in the lithium–pilocarpine model of SE, it does not exert hippocampal neuroprotection after SE. (AU)

Introducción La hormona de crecimiento (HC) es un factor que favorece la supervivencia neuronal en el hipocampo ante agresiones de diversa naturaleza. El status epilepticus (SE) es un tipo de crisis epiléptica de larga duración que produce muerte neuronal. El objetivo de este estudio fue evaluar el efecto de la administración intracerebroventricular de HC en la severidad de las convulsiones y la neurodegeneración hipocampal debida al SE. Metodología A ratas macho adultas se les implantó una cánula guía en el ventrículo lateral izquierdo y se les microinyectaron diferentes cantidades de HC (70, 120 o 220 ng/3 μl) durante 5 días; como vehículo se inyectó líquido cefalorraquídeo artificial. Las convulsiones se generaron con el modelo de litio-pilocarpina (3 mEq/kg LiCl y 30 mg/kg clorhidrato pilocarpina) un día después de la última inyección de HC. La neurodegeneración se identificó con la tinción de Fluoro-Jade B (F-JB). Resultados Las ratas a las que se les inyectaron 120 ng de HC requirieron 2 o 3 inyecciones de pilocarpina para desarrollar SE, en comparación con el resto de los grupos experimentales que requirieron solo una aplicación del convulsivante. Los registros EEG de la corteza prefrontal y parietal confirmaron que la latencia a las crisis generalizadas y al SE fue mayor en dicho grupo experimental. Todas las ratas con SE presentaron células positivas al FJ-B en el área CA1 e hilus del hipocampo, y no se identificaron diferencias entre los tratamientos. Conclusión Nuestros resultados muestran que, aunque la HC tiene un efecto anticonvulsivante, una vez que se ha desarrollado el SE no promueve neuroprotección en el hipocampo. (AU)

Evaluation of the anticonvulsant and neuroprotective effect of intracerebral administration of growth hormone in rats.

INTRODUCTION: The growth hormone (GH) has been reported as a crucial neuronal survival factor in the hippocampus against insults of diverse nature. Status epilepticus (SE) is a prolonged seizure that produces extensive neuronal cell death. The goal of this study was to evaluate the effect of intracerebroventricular administration of GH on seizure severity and SE-induced hippocampal neurodegeneration. METHODOLOGY: Adult male rats were implanted with a guide cannula in the left ventricle and different amounts of GH (70, 120 or 220ng/3µl) were microinjected for 5 days; artificial cerebrospinal fluid was used as the vehicle. Seizures were induced by the lithium-pilocarpine model (3mEq/kg LiCl and 30mg/kg pilocarpine hydrochloride) one day after the last GH administration. Neuronal injury was assessed by Fluoro-Jade B (F-JB) staining. RESULTS: Rats injected with 120ng of GH did not had SE after 30mg/kg pilocarpine, they required a higher number of pilocarpine injections to develop SE than the rats pretreated with the vehicle, 70ng or 220ng GH. Prefrontal and parietal cortex EEG recordings confirmed that latency to generalized seizures and SE was also significantly higher in the 120ng group when compared with all the experimental groups. FJ-B positive cells were detected in the hippocampus after SE in all rats, and no significant differences in the number of F-JB cells in the CA1 area and the hilus was observed between experimental groups. CONCLUSION: Our results indicate that, although GH has an anticonvulsive effect in the lithium-pilocarpine model of SE, it does not exert hippocampal neuroprotection after SE.

Exogenous growth hormone promotes an epithelial-mesenchymal hybrid phenotype in cancerous HeLa cells but not in non-cancerous HEK293 cells.

In cancer, the Epithelial to Mesenchymal Transition (EMT) is the process in which epithelial cells acquire mesenchymal features that allow metastasis, and chemotherapy resistance. Growth hormone (GH) has been associated with melanoma, breast, and endometrial cancer progression through an autocrine regulation of EMT. Since exogenous and autocrine expression of GH is known to have different molecular effects, we investigated whether exogenous GH is capable of regulating the EMT of cancer cells. Furthermore, we investigated whether exogenous GH could promote EMT in non-cancerous cells. To study the effect of GH (100 ng/ml) on cancer and non-cancer cells, we used HeLa and HEK293 cell lines, respectively. We evaluated the loss of cell-cell contacts, by cell scattering assay and migration by wound-healing assay. Additionally, we evaluated the morphological changes by phalloidin-staining. Finally, we evaluated the molecular markers E-cadherin and vimentin by flow cytometry. GH enhances cell scattering and the migratory rate and promotes morphological changes such as cell area increase and actin cytoskeleton filaments formation on HeLa cell line. Moreover, we found that GH favors the expression of the mesenchymal protein vimentin, followed by an increase in E-cadherin's epithelial protein expression, characteristics of an epithelial-mesenchymal hybrid phenotype that is associated with metastasis. On HEK293cells, GH promotes morphological changes, including cell area increment and filopodia formation, but not affects scattering, migration, nor EMT markers expression. Our results suggest that exogenous GH might participate in cervical cancer progression favoring a hybrid EMT phenotype but not on non-cancerous HEK293 cells.

Evaluation of the anticonvulsant and neuroprotective effect of intracerebral administration of growth hormone in rats.

INTRODUCTION: The growth hormone (GH) has been reported as a crucial neuronal survival factor in the hippocampus against insults of diverse nature. Status epilepticus (SE) is a prolonged seizure that produces extensive neuronal cell death. The goal of this study was to evaluate the effect of intracerebroventricular administration of GH on seizure severity and SE-induced hippocampal neurodegeneration. METHODOLOGY: Adult male rats were implanted with a guide cannula in the left ventricle and different amounts of GH (70, 120 or 220ng/3µl) were microinjected for 5 days; artificial cerebrospinal fluid was used as the vehicle. Seizures were induced by the lithium-pilocarpine model (3mEq/kg LiCl and 30mg/kg pilocarpine hydrochloride) one day after the last GH administration. Neuronal injury was assessed by Fluoro-Jade B (F-JB) staining. RESULTS: Rats injected with 120ng of GH did not had SE after 30mg/kg pilocarpine, they required a higher number of pilocarpine injections to develop SE than the rats pretreated with the vehicle, 70ng or 220ng GH. Prefrontal and parietal cortex EEG recordings confirmed that latency to generalized seizures and SE was also significantly higher in the 120ng group when compared with all the experimental groups. FJ-B positive cells were detected in the hippocampus after SE in all rats, and no significant differences in the number of F-JB cells in the CA1 area and the hilus was observed between experimental groups. CONCLUSION: Our results indicate that, although GH has an anticonvulsive effect in the lithium-pilocarpine model of SE, it does not exert hippocampal neuroprotection after SE.

Controlled clinical study of deep partial-thickness burns treated with frozen cultured human allogeneic epidermal sheets.

Numerous studies, many uncontrolled, have suggested that the application of freshly prepared human allogeneic epidermal cultures promotes faster re-epithelialization of skin donor sites and deep partial-thickness burns. We describe the results of a study of deep partial-thickness burns treated with such cultures preserved in the frozen state. The study was controlled, side-by-side comparative, and randomized. Nine patients with deep partial-thickness burns and 2 patients with superficial partial-thickness burns were treated with the frozen cultures, with the use of adjacent wounds covered with petrolatum-coated gauze (Jelonet, Smith & Nephew Inc, Largo, Fla) as control wounds. The results showed that for the 2 superficial partial-thickness burns, the frozen cultures reduced healing time by 44%. For 5 of the patients with deep partial-thickness burns, the wounds treated with frozen cultures healed in a mean time of 5.6 days, whereas the control wounds healed in 12.2 days. More importantly, for the 4 other patients with deep partial-thickness burns, the wounds treated with the frozen cultures underwent complete re-epithelialization in a mean time of 4.2 days, but the control wounds were partially or mostly unhealed at up to 14 days. The results show that the frozen cultures not only accelerate the re-epithelialization of deep and superficial partial-thickness burns but also make it possible to heal such wounds that otherwise would not heal.

Frozen human epidermal allogeneic cultures promote rapid healing of facial dermabrasion wounds.

BACKGROUND: Clinical studies have shown that cultured human epidermal allogenic sheets promote faster reepithelization of skin donor sites and deep partial-thickness wounds. OBJECTIVE: We describe the results of a controlled, clinical study of facial dermabrasion sites treated with a single application of frozen cultured human allogenic epidermal sheets that were thawed for 5-10 minutes at room temperature before application. METHODS: Ten patients with scars from acne or of other etiology underwent facial dermabrasion. One side of the face was treated with the frozen and thawed cultures, the other side was treated with standard dry dressing. RESULTS: The epidermal cultures promoted faster reepithelization of the wounds, with complete reepithelization in an average time of 4.6 days, whereas controls healed in an average of 7. 9 days. The reduction in healing time was 42% (P = 4.82 x 10(-7)). Pain was reduced in sites treated with the thawed cultures. CONCLUSION: Epidermal allogenic cultures, preserved by freezing, promoted significantly faster reepithelization and reduced pain intensity of dermabraded facial wounds, suggesting that they could be used routinely to improve the recovery from dermabrasion.

Functional domains of human growth hormone necessary for the adipogenic activity of hGH/hPL chimeric molecules.

Genetic analysis through construction of chimeric genes and their transfection in mammalian cells could provide a better understanding of biological functions of native or modified proteins, and would allow the design of new gene constructs encoding peptides that mimic or block ligand interaction with target tissues. To identify the hGH domains responsible for induction of adipose differentiation we constructed hGH/hPL chimeric molecules using homologous DNA mutagenesis, since hGH, but not human placental lactogen (hPL), promotes adipose differentiation in mouse 3T3-F442A cells. We assayed their adipogenic activity in an autocrine/paracrine biological model consisting of transiently transfected 3T3-F442A cells with the chimeric constructs. Plasmid DNAs carrying these constructs were transfected into growing 3T3-F442A cells, and cultures were further maintained for 7 days to differentiate into adipocytes. Secretion of transfected hGH/hPL chimeric proteins into the medium was in the range of 5-25 ng/ml. Adipogenic activity was a property only of those chimeric proteins that contained hGH exon III together with either hGH exon II or hGH IV. Our results also suggest that hGH binding site-2 is composed of two structural subdomains: subsite 2A encoded by exon II of hGH and subsite-2B encoded by exon IV. We also suggest that full adipogenic activity requires the presence of binding site-1 and any of the subsites of binding site-2. This simple autocrine/paracrine biological model of gene transfection allows the analysis of specific biological activity of products encoded by modified genes.

22-kDa and 20-kDa hGH isoforms show differential effects when assayed in 3T3-F442A and 3T3-F442A/C4 adipocytes.

To known whether 22.0-kDa human growth hormone (hGH22K) and the 20.0-kDa isoform (hGH20K) show different activities, we used 3T3-F442A and 3T3-F442A/C4 cells to evaluate their adipogenic and metabolic effects. Both isoforms had similar adipogenic and insulin-like activities. Lipolytic and diabetogenic effects of hGH22K were, respectively, 12.5 and 1.7-fold higher than those found for hGH20K. The 3T3-F442A/C4 clone was not responsive to insulin-like and diabetogenic effects of hGH. The results suggest that adipogenic and lipolytic effects of hGH are mediated by mechanisms different from those involved in insulin-like and diabetogenic activities.