Qualitative and quantitative analysis of rabbit's fat mesenchymal stem cells / Análise quantitativa e qualitativa de células tronco mesênquimais da gordura de coelhos

PURPOSE: To present an experimental model of qualitative and quantitative analysis of mesenchymal stem cells from fat of rabbits obtained by lipectomy. The fat could be a great source for obtaining mesenchymal stem cells and to create conditions for repairing injured tissues by bioengineering. METHODS: New Zealand rabbits (n= 10) adipose panicle (2-3 cm) were removed by lipectomy, fragmented and washed with PBS and enzymatically dissociated with trypsin/EDTA. Lately, these cells were incubated in culture medium DMEM and after 20 days, was performed quantitative analysis of the accession of first and second mesenchymal cells in cell culture bottles. RESULTS: The fat total cells (CTF) were 1.62 x10(6) cells/mL and presented 98 percent of viability. These cells were taken for cultivation and after 20 days were counted 2.88 x10(6) cells/mL MSC. The same was done and after 20 days we quantified 4.28 x10(6) cells/mL MSC. CONCLUSION: The lipectomy of adipose panicule is a very satisfactory method to extract stem cells from fat, quantitatively and qualitatively.

OBJETIVO: Apresentar um modelo experimental de análise qualitativa e quantitativa de células tronco mesênquimais proveniente da gordura de coelhos obtido por lipectomia. A gordura poderia ser uma grande fonte de obtenção de células tronco mesenquimais, criando condições para a reparação de tecidos lesados. MÉTODOS: Foram removidos os panículos adiposos (2-3 cm) da região cervical de Coelhos Nova Zelândia (n = 10) por lipectomia. Os panículos foram fragmentados e lavados com PBS e, posteriormente, dissociados enzimaticamente com tripsina / EDTA. As células extraídas do panículo adiposo foram incubadas em meio de cultura DMEM e após 20 dias, foi realizada uma análise quantitativa da adesão de primeira e segunda passagem das células mesênquimais em garrafas de cultura. RESULTADOS: Foram extraídas 1,62 x106 cel/ mL células totais de gordura (CTG) with 98 por cento de viabilidade. Essas células foram levadas para o cultivo e após 20 dias, foi realizada a primeira passagem (1pd) sendo quantificadas 2,88 x10(6) cel/mL células tronco mesênquimais (CTM). Na segunda passagem (2pd) foi obtido 4,28 x10(6) cel/mL CTM. CONCLUSÃO: A lipectomia do paniculo adiposo é um método muito satisfatório para extrair células tronco a partir de gordura, quantitativamente e qualitativamente.

Comparative study of technique to obtain stem cells from bone marrow collection between the iliac crest and the femoral epiphysis in rabbits / Estudo comparativo da técnica para a obtenção de células tronco pela coleta de medula óssea entre a crista ilíaca e epífise do fêmur em coelhos

PURPOSE: To assess the technique for the collection of rabbit bone marrow stem cells from different regions to be used as an experimental model in regenerative medicine. METHODS: Thirty rabbits were allocated into 2 groups: GROUP A, n=8, animals that underwent bone marrow blood (BMB) harvesting from the iliac crest; and GROUP B: including 22 rabbits that underwent BMB harvesting from the femur epiphysis. After harvesting, mononuclear cells were isolated by density gradient centrifugation (Ficoll - Histopaque). The number of mononuclear cells per ml was counted in a Neubauer chamber and cell viability was checked through Tripan Blue method. RESULTS: Harvesting from the iliac crest yielded an average of 1 ml of BMB and 3,6.10(6) cells/ml over 1 hour of surgery, whereas an average of 3ml of BMB and 11,79.10(6) cells./ml were obtained in 30 min from the femur epiphysis with a reduced animal death rate. CONCLUSION: The analysis for the obtention of a larger number of mononuclear cells/ml from rabbit bone marrow blood was more satisfactory in the femur epiphysis than in the iliac crest.

OBJETIVO: Avaliar a técnica mais promissora para a coleta de células tronco adultas de medula óssea de coelhos para a utilização do mesmo como modelo experimental na medicina regenerativa. MÉTODOS: Foram utilizados 30 coelhos divididos em 2 grupos: GRUPO A, n=8, onde realizamos a coleta de sangue de medula óssea (MO) da crista ilíaca e grupo B, n=22, onde realizamos a coleta de sangue da medula óssea da epífise do fêmur. Após as coletas, realizamos a separação das células mononucleadas através do gradiente de densidade (Ficoll-Hystopaque). Através da câmara de Neubauer realizamos a contagem das células mononucleadas por ml. Testamos a viabilidade celular através do método Tripan Blue. RESULTADOS: Na coleta de sangue de MO na crista ilíaca obtivemos a média de 1 ml durante 1 hora de procedimento cirúrgico, obtendo a quantidade de 3,6 .10(6) células/ml, enquanto que a punção na epífise do fêmur obtivemos a média de 3 ml durante 30 minutos de procedimento cirúrgico obtendo a quantidade de 11,79.10(6) cél./ml diminuindo o óbito dos animais. CONCLUSÃO: A análise para a obtenção de maior número de células mononucleadas/ml de sangue de medula óssea de coelho foi mais satisfatória na região da epífise do fêmur em comparação com a crista ilíaca.

Avaliação morfológica e dos mecanismos de mobilização de Ca2+ pela glicose e acetilcolina em células pancreáticas humanas / Morphologic evaluation and Ca2+ mobilization by glicose and acetylcholine in human pancreatic cells

OBJETIVOS: Avaliar a morfologia das organelas e do citoesqueleto em células pancreáticas humanas cultivadas e a mobilização de Ca2+ em resposta à glicose e ACh por medidas fluorimétricas. MATERIAL E MÉTODOS: As células foram semeadas em lamínulas, fixadas e marcadas com uma combinação de fluoróforos: o núcleo foi corado com DAPI e as mitocôndrias, com Mytotracker Red. Foram utilizados faloidina e anticorpos secundários conjugados com Alexa Fluor verde e vermelho fluorescentes (488 e 594) para identificar proteína actina F e receptor muscarínico tipo M3, respectivamente. Para estudar a mobilização de Ca2+, as células foram incubadas com fura-2/AM. RESULTADOS: As células pancreáticas humanas apresentaram morfologia preservada com grande quantidade de mitocôndrias. Na região de maior densidade celular, evidenciou-se as pseudo-ilhotas e os receptores muscarínicos M3. Por meio da elevação da [Ca2+]c, devido à ação da glicose e ACh, mostrou-se preservação da capacidade responsiva a esses estímulos e foi dependente de concentração desses agonistas. A glicose promoveu uma resposta sustentada e a ACh induziu uma resposta bifásica. CONCLUSÃO: As células pancreáticas humanas cultivadas conservaram sua morfologia. A mobilização de Ca2+ em resposta à glicose e a ACh confirma a sua funcionalidade. Os receptores muscarínicos M3 estão presentes nessas células.

AIMS: The proposal of this study was to analyze morphology of the organelles and cytoskeleton in human pancreatic cells cultured and the mobilization of the cytosolic calcium ([Ca2+]c) in response to glucose and ACh by fluorimetry method. MATERIAL AND METHODS: The cells were plated on glass coverslips, fixed and stained with a combination of fluorophores: the nuclei were stained with DAPI and mitochondria with Mytotracker Red. It was used phalloidin and the secondary antibodies Alexa Fluor conjugated green and red-fluorescent (488 and 594) to identify the protein cell actin F and type M3 muscarinic receptor respectively. The cells also were loaded with fura-2/AM to study Ca2+ mobilization. RESULTS: The human pancreatic cells show characteristics morphologically preserved with great amount of mitochondria. In region major cell density was evidenced pseudo-islets and type M3 muscarinic receptors. Through increase of [Ca2+]c due to action of glucose and ACh were shown that the cellsÆ capacity to respond to these stimuli were conserved. The elevation of the [Ca2+]c depended on concentration by glucose-induced promoting sustained phase and ACh-induced a biphasic response. CONCLUSION: The morphologic characteristics of human pancreatic cells cultured were preserved. The Ca2+ mobilization in response to glucose and ACh confirmed its functionality. The expression of the M3 muscarinic receptors in human pancreatic cell cultured was demonstrated.

Calcium handling in a testosterone responsive skeletal muscle of the MDX mouse

Muscle necrosis in Duchenne muscle dystrophy (DMD) and in the mdx mouse has been related to abnormal calcium homeostasis associated with the lack of dystrophin. We have previously shown that the testosterone-dependent levator ani (LA) muscle of the mdx mouse develops a mild muscle wasting and fiber degeneration compared to the less hormone sensitive diaphragm (DIA) muscle, suggesting a protective effect of androgens. This study assessed the calcium handling mechanisms and cytosolic calcium concentration ([Ca2+]i) in LA muscles of mdx mice at critical stages of muscle disease. Muscle contractures induced by caffeine and 4-chloro-m-cresol (4-CmC), two activators of ryanodine channels, were recorded in LA and DIA muscles of prepubertal (1 month-old), adult (4 month-old) and aged (18 month-old) wild-type (wt) and mdx mice. [Ca2+]i was estimated with the fura-2 fluorescent dye in enzymatically dissociated LA muscle fibers of the same wt and mdx groups. Tetanus tension (TT) in the LA increased proportionately to the muscle weight (4 to 5-fold), but specific TT (TT/mg) did not differ among age-matched wt and mdx groups. Muscle contractures induced by caffeine (3-100 mM) or 4-CmC (0.1-5.0 mM) in the LA were greater in prepubertal than in adult and aged mice, but they did not differ among age-matched wt and mdx groups. The resting [Ca2+]i in mdx LA muscle fibers was not significantly affected at any age. Comparatively, dystrophic DIA presented reduced muscle strength in adult (40%) and aged (45%) mice, whereas the muscle responses to caffeine increased with age (63 to 82%), indicating changes in the Ca2+ handling mechanisms. The results indicated that muscle strength and calcium homeostasis in dystrophic LA muscle fibers were not significantly altered, confirming previous evidence of androgens’ beneficial effects on hormone-sensitive skeletal muscles.