Eder João Arruda

Proposal of non-invasive experimental model to induce scoliosis in rats

BACKGROUND In the literature, there are several experimental models that induce scoliosis in rats; however, they make use of drugs or invasive interventions to generate a scoliotic curve. OBJECTIVES To design and apply a non-invasive immobilization model to induce scoliosis in rats. METHODS Four-week old male Wistar rats (85±3.3g) were divided into two groups: control (CG) and scoliosis (SG). The animals in the SG were immobilized by two vests (scapular and pelvic) made from polyvinyl chloride (PVC) and externally attached to each other by a retainer that regulated the scoliosis angle for twelve weeks with left convexity. After immobilization, the abdominal, intercostal, paravertebral, and pectoral muscles were collected for chemical and metabolic analyses. Radiographic reports were performed every 30 days over a 16-week period. RESULTS The model was effective in the induction of scoliosis, even 30 days after immobilization, with a stable angle of 28±5º. The chemical and metabolic analyses showed a decrease (p<0.05) in the glycogenic reserves and in the relationship between DNA and total protein reserves of all the muscles analyzed in the scoliosis group, being lower (p<0.05) in the convex side. The values for the Homeostatic Model Assessment of Insulin Resistance indicated a resistance condition to insulin (p<0.05) in the scoliosis group (0.66±0.03), when compared to the control group (0.81±0.02). CONCLUSIONS The scoliosis curvature remained stable 30 days after immobilization. The chemical and metabolic analyses suggest changes in muscular homeostasis during the induced scoliosis process.

Comparação das reservas glicogênicas em ratos jovens e envelhecidos tratados com picolinato de cromo

INTRODUCCION: Entre los suplementos que se usan en los deportes, el mineral cromo ha sido distinguido, en particular por el aumento de la accion de la via de la insulina, una accion muy importante en el mantenimiento de la homeostasis metabolica. La accion del cromo parece tener una accion significativa como coadyuvante en la dinamica de la accion de la insulina.OBJETIVO: Evaluar el perfil del glucogeno y la sensibilidad de los tejidos a la insulina y de la glucosa pancreatica en ratas jovenes y envejecidas tratadas con picolinato de cromo.METODOS: Se utilizaron ratas Wistar con edades de 3 y 24 meses, divididas en cuatro grupos experimentales (n = 6), llamados asi: jovenes (Y), jovenes complementados con picolinato de cromo (JP, 80 mg/Kg.), envejecidos (E) y envejecidos suplementados con picolinato de cromo (EP 80 mg/Kg.). La sensibilidad a la insulina se evaluo mediante la prueba de tolerancia a la insulina (ITT, 2 U/Kg.) y la sensibilidad pancreatica, mediante la prueba de tolerancia a la glucosa (GTT, 2 g/Kg.). En el analisis estadistico se utilizo la prueba de normalidad de Kolmogorov-Smirnov seguida por ANOVA y la prueba post-hoc de Tukey, p < 0,05.RESULTADOS: El grupo de ratas envejecidas mostro reservas de glucogeno mas bajas en comparacion con el grupo de jovenes; a su vez, el tratamiento con picolinato de cromo causo la elevacion de las reservas hepaticas sin efecto en ratas jovenes. Al mismo analisis de perfiles, se demostro que el tratamiento con picolinato de cromo promovio un aumento de las reservas de glucogeno muscular, efecto observado en ratas jovenes y envejecidas. En el grupo joven, no se observo ninguna diferencia en la ITT, pero hubo una reduccion en el area bajo la curva en la GTT. En el grupo envejecido, hubo aumento en la capacidad de respuesta a la insulina en la ITT y reduccion en el area bajo la curva.CONCLUSION: El picolinato expreso una accion secretagoga y sensibilizadora de la accion de la insulina, con la expresion mas significativa en los musculos envejecidos.INTRODUCAO: Entre os suplementos utilizados no meio esportivo, o mineral cromo tem se destacado, principalmente por potencializar a acao da via insulinica, acao extremamente importante na manutencao da homeostasia metabolica. A acao do cromo parece ter acao importante como coadjuvante nas dinâmicas da acao insulinica.OBJETIVO: Avaliar o perfil glicogenico, bem como a sensibilidade tecidual a insulina e a pancreatica a glicose em ratos jovens e envelhecidos tratados com picolinato de cromo.METODO: Foram utilizados ratos Wistar, com idade de 3 e 24 meses, distribuidos em quatro grupos experimentais (n = 6), assim denominados: jovens (J), jovens suplementados com picolinato de cromo (JP, 80 µg/Kg), envelhecidos (E) e envelhecidos suplementados com picolinato de cromo (EP, 80 µg/Kg). A sensibilidade a insulina foi avaliada atraves do teste de tolerância a insulina (ITT, 2 U/Kg) e a sensibilidade pancreatica, atraves do teste de tolerância a glicose (GTT, 2 g/Kg). Na analise estatistica foi utilizado teste de normalidade de dados de Kolmogorov-Smirnov, seguido de ANOVA e o teste post-hoc de Tukey, p < 0,05.RESULTADOS: O grupo envelhecido apresentou menores reservas glicogenicas se comparado ao grupo jovem; por sua vez, o tratamento com picolinato promoveu elevacao das reservas hepaticas de ratos jovens sem efeito nos envelhecidos. No mesmo perfil de analise, foi demonstrado que o tratamento com picolinato promoveu elevacao das reservas glicogenicas musculares, efeito observado tanto nos jovens quanto nos envelhecidos. No grupo jovem, nao foi observada diferenca no ITT, porem houve reducao da area sob a curva descrita no GTT. No grupo envelhecido, houve elevacao da responsividade a insulina no ITT e reducao da area sob a curva.CONCLUSAO: O picolinato expressou acao de secretagogo e sensibilizador da acao insulinica, com expressao mais significativa nos musculos envelhecidos.Introduction: Among the supplements used in sports, the mineral chromium has stood out particularly by enhancing the action of insulin route, action extremely important in maintaining metabolic homeostasis. The chromium action seems to have significant action as an adjunct in the dynamics of insulin action. Objective: To evaluate the glycogen profile and the tissue sensitivity to insulin and pancreatic glucose sensitivity in young and aged rats treated with chromium picolinate. Methods: Wistar rats were used, aged 3 and 24 months, divided into four experimental groups (n = 6), so named: young (Y), young supplemented with chromium picolinate (YP, 80 μg/kg), aged (A) and aged supplemented with chromium picolinate (AP, 80 μg/kg). The insulin sensitivity was assessed by the insulin tolerance test (ITT, 2U/Kg) and pancreatic sensitivity was assessed by the glucose tolerance test (GTT, 2 g/Kg). Statistical analysis used Kolmogorov-Smirnov Test for Normality, followed by ANOVA and Tukey’s Post-hoc test, p <0.05. Results: The aged group showed lower glycogen reserves compared to the young group; in turn, treatment with chromium picolinate causes an increase in liver reserves of young rats with no effect on aged rats. At the same profile analysis, it was shown that treatment with chromium picolinate promoted an increase in muscle glycogen reserves, effect observed in both young and aged rats. In the young group, no difference was observed in the ITT, but there was a decrease of the area under the curve described in GTT. In the aged group, there was an increase in responsiveness to insulin in the ITT and decrease of the area under the curve. Conclusion: The chromium picolinate expressed secretagogue and sensitizer action of insulin action with most significant expression in aging muscles.

Glycogen reserves in young and aged rats treated with chromium picolinate

INTRODUCCION: Entre los suplementos que se usan en los deportes, el mineral cromo ha sido distinguido, en particular por el aumento de la accion de la via de la insulina, una accion muy importante en el mantenimiento de la homeostasis metabolica. La accion del cromo parece tener una accion significativa como coadyuvante en la dinamica de la accion de la insulina.OBJETIVO: Evaluar el perfil del glucogeno y la sensibilidad de los tejidos a la insulina y de la glucosa pancreatica en ratas jovenes y envejecidas tratadas con picolinato de cromo.METODOS: Se utilizaron ratas Wistar con edades de 3 y 24 meses, divididas en cuatro grupos experimentales (n = 6), llamados asi: jovenes (Y), jovenes complementados con picolinato de cromo (JP, 80 mg/Kg.), envejecidos (E) y envejecidos suplementados con picolinato de cromo (EP 80 mg/Kg.). La sensibilidad a la insulina se evaluo mediante la prueba de tolerancia a la insulina (ITT, 2 U/Kg.) y la sensibilidad pancreatica, mediante la prueba de tolerancia a la glucosa (GTT, 2 g/Kg.). En el analisis estadistico se utilizo la prueba de normalidad de Kolmogorov-Smirnov seguida por ANOVA y la prueba post-hoc de Tukey, p < 0,05.RESULTADOS: El grupo de ratas envejecidas mostro reservas de glucogeno mas bajas en comparacion con el grupo de jovenes; a su vez, el tratamiento con picolinato de cromo causo la elevacion de las reservas hepaticas sin efecto en ratas jovenes. Al mismo analisis de perfiles, se demostro que el tratamiento con picolinato de cromo promovio un aumento de las reservas de glucogeno muscular, efecto observado en ratas jovenes y envejecidas. En el grupo joven, no se observo ninguna diferencia en la ITT, pero hubo una reduccion en el area bajo la curva en la GTT. En el grupo envejecido, hubo aumento en la capacidad de respuesta a la insulina en la ITT y reduccion en el area bajo la curva.CONCLUSION: El picolinato expreso una accion secretagoga y sensibilizadora de la accion de la insulina, con la expresion mas significativa en los musculos envejecidos.INTRODUCAO: Entre os suplementos utilizados no meio esportivo, o mineral cromo tem se destacado, principalmente por potencializar a acao da via insulinica, acao extremamente importante na manutencao da homeostasia metabolica. A acao do cromo parece ter acao importante como coadjuvante nas dinâmicas da acao insulinica.OBJETIVO: Avaliar o perfil glicogenico, bem como a sensibilidade tecidual a insulina e a pancreatica a glicose em ratos jovens e envelhecidos tratados com picolinato de cromo.METODO: Foram utilizados ratos Wistar, com idade de 3 e 24 meses, distribuidos em quatro grupos experimentais (n = 6), assim denominados: jovens (J), jovens suplementados com picolinato de cromo (JP, 80 µg/Kg), envelhecidos (E) e envelhecidos suplementados com picolinato de cromo (EP, 80 µg/Kg). A sensibilidade a insulina foi avaliada atraves do teste de tolerância a insulina (ITT, 2 U/Kg) e a sensibilidade pancreatica, atraves do teste de tolerância a glicose (GTT, 2 g/Kg). Na analise estatistica foi utilizado teste de normalidade de dados de Kolmogorov-Smirnov, seguido de ANOVA e o teste post-hoc de Tukey, p < 0,05.RESULTADOS: O grupo envelhecido apresentou menores reservas glicogenicas se comparado ao grupo jovem; por sua vez, o tratamento com picolinato promoveu elevacao das reservas hepaticas de ratos jovens sem efeito nos envelhecidos. No mesmo perfil de analise, foi demonstrado que o tratamento com picolinato promoveu elevacao das reservas glicogenicas musculares, efeito observado tanto nos jovens quanto nos envelhecidos. No grupo jovem, nao foi observada diferenca no ITT, porem houve reducao da area sob a curva descrita no GTT. No grupo envelhecido, houve elevacao da responsividade a insulina no ITT e reducao da area sob a curva.CONCLUSAO: O picolinato expressou acao de secretagogo e sensibilizador da acao insulinica, com expressao mais significativa nos musculos envelhecidos.Introduction: Among the supplements used in sports, the mineral chromium has stood out particularly by enhancing the action of insulin route, action extremely important in maintaining metabolic homeostasis. The chromium action seems to have significant action as an adjunct in the dynamics of insulin action. Objective: To evaluate the glycogen profile and the tissue sensitivity to insulin and pancreatic glucose sensitivity in young and aged rats treated with chromium picolinate. Methods: Wistar rats were used, aged 3 and 24 months, divided into four experimental groups (n = 6), so named: young (Y), young supplemented with chromium picolinate (YP, 80 μg/kg), aged (A) and aged supplemented with chromium picolinate (AP, 80 μg/kg). The insulin sensitivity was assessed by the insulin tolerance test (ITT, 2U/Kg) and pancreatic sensitivity was assessed by the glucose tolerance test (GTT, 2 g/Kg). Statistical analysis used Kolmogorov-Smirnov Test for Normality, followed by ANOVA and Tukey’s Post-hoc test, p <0.05. Results: The aged group showed lower glycogen reserves compared to the young group; in turn, treatment with chromium picolinate causes an increase in liver reserves of young rats with no effect on aged rats. At the same profile analysis, it was shown that treatment with chromium picolinate promoted an increase in muscle glycogen reserves, effect observed in both young and aged rats. In the young group, no difference was observed in the ITT, but there was a decrease of the area under the curve described in GTT. In the aged group, there was an increase in responsiveness to insulin in the ITT and decrease of the area under the curve. Conclusion: The chromium picolinate expressed secretagogue and sensitizer action of insulin action with most significant expression in aging muscles.

Reservas de glucógeno en ratas jóvenes y envejecidas tratadas con picolinato de cromo

INTRODUCCION: Entre los suplementos que se usan en los deportes, el mineral cromo ha sido distinguido, en particular por el aumento de la accion de la via de la insulina, una accion muy importante en el mantenimiento de la homeostasis metabolica. La accion del cromo parece tener una accion significativa como coadyuvante en la dinamica de la accion de la insulina.OBJETIVO: Evaluar el perfil del glucogeno y la sensibilidad de los tejidos a la insulina y de la glucosa pancreatica en ratas jovenes y envejecidas tratadas con picolinato de cromo.METODOS: Se utilizaron ratas Wistar con edades de 3 y 24 meses, divididas en cuatro grupos experimentales (n = 6), llamados asi: jovenes (Y), jovenes complementados con picolinato de cromo (JP, 80 mg/Kg.), envejecidos (E) y envejecidos suplementados con picolinato de cromo (EP 80 mg/Kg.). La sensibilidad a la insulina se evaluo mediante la prueba de tolerancia a la insulina (ITT, 2 U/Kg.) y la sensibilidad pancreatica, mediante la prueba de tolerancia a la glucosa (GTT, 2 g/Kg.). En el analisis estadistico se utilizo la prueba de normalidad de Kolmogorov-Smirnov seguida por ANOVA y la prueba post-hoc de Tukey, p < 0,05.RESULTADOS: El grupo de ratas envejecidas mostro reservas de glucogeno mas bajas en comparacion con el grupo de jovenes; a su vez, el tratamiento con picolinato de cromo causo la elevacion de las reservas hepaticas sin efecto en ratas jovenes. Al mismo analisis de perfiles, se demostro que el tratamiento con picolinato de cromo promovio un aumento de las reservas de glucogeno muscular, efecto observado en ratas jovenes y envejecidas. En el grupo joven, no se observo ninguna diferencia en la ITT, pero hubo una reduccion en el area bajo la curva en la GTT. En el grupo envejecido, hubo aumento en la capacidad de respuesta a la insulina en la ITT y reduccion en el area bajo la curva.CONCLUSION: El picolinato expreso una accion secretagoga y sensibilizadora de la accion de la insulina, con la expresion mas significativa en los musculos envejecidos.INTRODUCAO: Entre os suplementos utilizados no meio esportivo, o mineral cromo tem se destacado, principalmente por potencializar a acao da via insulinica, acao extremamente importante na manutencao da homeostasia metabolica. A acao do cromo parece ter acao importante como coadjuvante nas dinâmicas da acao insulinica.OBJETIVO: Avaliar o perfil glicogenico, bem como a sensibilidade tecidual a insulina e a pancreatica a glicose em ratos jovens e envelhecidos tratados com picolinato de cromo.METODO: Foram utilizados ratos Wistar, com idade de 3 e 24 meses, distribuidos em quatro grupos experimentais (n = 6), assim denominados: jovens (J), jovens suplementados com picolinato de cromo (JP, 80 µg/Kg), envelhecidos (E) e envelhecidos suplementados com picolinato de cromo (EP, 80 µg/Kg). A sensibilidade a insulina foi avaliada atraves do teste de tolerância a insulina (ITT, 2 U/Kg) e a sensibilidade pancreatica, atraves do teste de tolerância a glicose (GTT, 2 g/Kg). Na analise estatistica foi utilizado teste de normalidade de dados de Kolmogorov-Smirnov, seguido de ANOVA e o teste post-hoc de Tukey, p < 0,05.RESULTADOS: O grupo envelhecido apresentou menores reservas glicogenicas se comparado ao grupo jovem; por sua vez, o tratamento com picolinato promoveu elevacao das reservas hepaticas de ratos jovens sem efeito nos envelhecidos. No mesmo perfil de analise, foi demonstrado que o tratamento com picolinato promoveu elevacao das reservas glicogenicas musculares, efeito observado tanto nos jovens quanto nos envelhecidos. No grupo jovem, nao foi observada diferenca no ITT, porem houve reducao da area sob a curva descrita no GTT. No grupo envelhecido, houve elevacao da responsividade a insulina no ITT e reducao da area sob a curva.CONCLUSAO: O picolinato expressou acao de secretagogo e sensibilizador da acao insulinica, com expressao mais significativa nos musculos envelhecidos.Introduction: Among the supplements used in sports, the mineral chromium has stood out particularly by enhancing the action of insulin route, action extremely important in maintaining metabolic homeostasis. The chromium action seems to have significant action as an adjunct in the dynamics of insulin action. Objective: To evaluate the glycogen profile and the tissue sensitivity to insulin and pancreatic glucose sensitivity in young and aged rats treated with chromium picolinate. Methods: Wistar rats were used, aged 3 and 24 months, divided into four experimental groups (n = 6), so named: young (Y), young supplemented with chromium picolinate (YP, 80 μg/kg), aged (A) and aged supplemented with chromium picolinate (AP, 80 μg/kg). The insulin sensitivity was assessed by the insulin tolerance test (ITT, 2U/Kg) and pancreatic sensitivity was assessed by the glucose tolerance test (GTT, 2 g/Kg). Statistical analysis used Kolmogorov-Smirnov Test for Normality, followed by ANOVA and Tukey’s Post-hoc test, p <0.05. Results: The aged group showed lower glycogen reserves compared to the young group; in turn, treatment with chromium picolinate causes an increase in liver reserves of young rats with no effect on aged rats. At the same profile analysis, it was shown that treatment with chromium picolinate promoted an increase in muscle glycogen reserves, effect observed in both young and aged rats. In the young group, no difference was observed in the ITT, but there was a decrease of the area under the curve described in GTT. In the aged group, there was an increase in responsiveness to insulin in the ITT and decrease of the area under the curve. Conclusion: The chromium picolinate expressed secretagogue and sensitizer action of insulin action with most significant expression in aging muscles.

Desuso gerado por colete de retificação de coluna: estudo experimental

The spine is the main support and movement axis of the locomotor system, and numberless clinical conditions may require that this structure be submitted to functional restriction. Among the non-invasive treatments used in spinal or appendicular skeleton injuries, the immobilization of the spine is used as a rehabilitation strategy. Because of the functional restrictions generated by restraining devices used on the spine, the proposal of this study was to adapt a spinal orthosis on rats, thus mimicking the immobilization of corrective vests and assessing the energetic conditions of thoracic muscles after 12 weeks of application. Wistar rats that were 42 days old were used in this study (post-weaning period), followed-up for 12 weeks in 2 groups called control (C) and rectification vests (R), which were made of PVC to immobilize the spine. The following concentrations were evaluated: glycogen (GLY) of the paravertebral muscle and the thorax; total proteins and DNA (TP/DNA) and interleukin-6 (IL-6). The normality Kolmogorov-Smirnov test was used for statistical analysis, followed by the Tukey test. A 5% level was established for all of the calculations. It was observed that group R presented 12% less body mass and GLY stores 21% lower; the ratio between TP/DNA was in average 6.6% lower; IL-6 concentrations were in average 25% higher. The study shows that the movement restriction in the spine leads to energetic crisis and compromised muscular development. More studies should be conducted with this model to generate physical therapy strategies that could reduce muscle compromise after spine immobilization.

Disuse induced by the spine rectification vest: experimental study

The spine is the main support and movement axis of the locomotor system, and numberless clinical conditions may require that this structure be submitted to functional restriction. Among the non-invasive treatments used in spinal or appendicular skeleton injuries, the immobilization of the spine is used as a rehabilitation strategy. Because of the functional restrictions generated by restraining devices used on the spine, the proposal of this study was to adapt a spinal orthosis on rats, thus mimicking the immobilization of corrective vests and assessing the energetic conditions of thoracic muscles after 12 weeks of application. Wistar rats that were 42 days old were used in this study (post-weaning period), followed-up for 12 weeks in 2 groups called control (C) and rectification vests (R), which were made of PVC to immobilize the spine. The following concentrations were evaluated: glycogen (GLY) of the paravertebral muscle and the thorax; total proteins and DNA (TP/DNA) and interleukin-6 (IL-6). The normality Kolmogorov-Smirnov test was used for statistical analysis, followed by the Tukey test. A 5% level was established for all of the calculations. It was observed that group R presented 12% less body mass and GLY stores 21% lower; the ratio between TP/DNA was in average 6.6% lower; IL-6 concentrations were in average 25% higher. The study shows that the movement restriction in the spine leads to energetic crisis and compromised muscular development. More studies should be conducted with this model to generate physical therapy strategies that could reduce muscle compromise after spine immobilization.

Desuso generado por el corsé de rectificación de la columna: estudio experimenta

The spine is the main support and movement axis of the locomotor system, and numberless clinical conditions may require that this structure be submitted to functional restriction. Among the non-invasive treatments used in spinal or appendicular skeleton injuries, the immobilization of the spine is used as a rehabilitation strategy. Because of the functional restrictions generated by restraining devices used on the spine, the proposal of this study was to adapt a spinal orthosis on rats, thus mimicking the immobilization of corrective vests and assessing the energetic conditions of thoracic muscles after 12 weeks of application. Wistar rats that were 42 days old were used in this study (post-weaning period), followed-up for 12 weeks in 2 groups called control (C) and rectification vests (R), which were made of PVC to immobilize the spine. The following concentrations were evaluated: glycogen (GLY) of the paravertebral muscle and the thorax; total proteins and DNA (TP/DNA) and interleukin-6 (IL-6). The normality Kolmogorov-Smirnov test was used for statistical analysis, followed by the Tukey test. A 5% level was established for all of the calculations. It was observed that group R presented 12% less body mass and GLY stores 21% lower; the ratio between TP/DNA was in average 6.6% lower; IL-6 concentrations were in average 25% higher. The study shows that the movement restriction in the spine leads to energetic crisis and compromised muscular development. More studies should be conducted with this model to generate physical therapy strategies that could reduce muscle compromise after spine immobilization.

Propriedades Glicostáticas em Eritrócitos de Ratas Tratadas com Tamoxifeno

Tamoxifen is a drug that has been widely used in chemoprevention of breast cancer, yet little is known about the possible effects on erythrocytes. Wistar rats (3-4 months) were divided into two groups namely: control and treated with tamoxifen, n = 6. After anesthesia (sodium pentobarbital 40 mg / kg, ip) blood was collected with heparinized syringes from the femoral artery and vein and the portal vein and supra-hepatic being directed to evaluation of blood glucose with the use of tapes used in glicotest, hemoglobin concentration through laboratory application kit and glycogen reserves through micro-enzymatic method. A second aliquot of blood was collected from the renal vein and directed toward evaluating the properties glucostatic in vitro . Statistical analysis used ANOVA and Tukey test, p in vivo were repeated in vitro . It was also observed that the capacity glucostatic was compromised in the presence of tamoxifen. Tamoxifen inhibits the functions of erythrocyte glucostatic properties by modifying enzymatic functions and / or structural.