Vanessa Amaral Mendonça

High intensity interval training modulates hippocampal oxidative stress, BDNF and inflammatory mediators in rats

Although High Intensity Interval Training (HIIT) are being associated to increase cardiovascular and metabolic adaptation, there is controversy and limited information about the effects of HIIT on hippocampal oxidative stress, pro- and anti-inflammatory cytokines balance and neurotrophic status. Thus, this study evaluated the effects of six weeks of HIIT on hippocampal redox state (oxidative damage and enzymatic and non-enzymatic antioxidant defenses), neuroimmune mediators (TNFα, IL-6, IL-1β and IL-10) and brain-derived neurotrophic (BDNF) levels. After six weeks of HIIT young adults male Wistar rats presented reduced oxidative damage and increased enzymatic (superoxide dismutase) and non-enzymatic activity in hippocampus. Moreover HIIT induced a decrease in cytokine content (TNFα, IL-6, IL-1β and IL-10) and enhanced hippocampal BDNF levels. In conclusion, the present study showed for the first time a positive effect of six weeks of HIIT on reducing hippocampal oxidative stress by decreasing lipoperoxidation and inflammatory markers, as well enhancing antioxidant defenses and BDNF content.

Central cholinergic activation induces greater thermoregulatory and cardiovascular responses in spontaneously hypertensive than in normotensive rats

There is evidence that central cholinergic stimulation increases heat dissipation in normotensive rats besides causing changes on the cardiovascular system via modulation of baroreceptors activity. However, the contribution of the central cholinergic system on thermoregulatory responses and its relationship with cardiovascular adjustments in spontaneously hypertensive rats (SHRs), an animal model of reduced baroreceptor sensitivity and thermoregulatory deficit, has not been completely clarified. Therefore, the aim of this study was to verify the involvement of the central cholinergic system in cardiovascular and thermoregulatory adjustments in SHRs. Male Wistar rats (n = 17) and SHRs (n = 17) were implanted with an intracerebroventricular cannula for injections of 2 µL of physostigmine (phy) or saline solution. Tail temperature (Ttail), internal body temperature (Tint), systolic arterial pressure (SAP), heart rate (HR) and metabolic rate were registered during 60 min while the animals remained at rest after randomly receiving the injections. The variability of the SAP and the HR was estimated by the fast Fourier transform. Phy treatment began a succession of cardiovascular and thermoregulatory responses that resulted in increased SAP, reduced HR and increased Ttail in both Wistar and SHRs groups. The magnitude of these effects seems to be more intense in SHRs, since the improvement of heat dissipation reflected in Tint. Taken together, these results provide evidence that hypertensive rats present greater cardiovascular and thermoregulatory responses than normotensive rats after central cholinergic stimulation.

Comparison of respiratory muscle strength between fragility subgroups in community elderly

A fragilidade e composta por um tripe constituido por: sarcopenia, disfuncao imunologica e desregulacao neuroendocrina. A sarcopenia e definida como uma diminuicao na forca e na potencia muscular, sendo que os musculos respiratorios tambem sao afetados. O objetivo foi comparar a forca muscular respiratoria (FMR) em idosas residentes na comunidade, classificadas como nao frageis (NF), pre-frageis (PF) e frageis (F) e correlacionar a FMR com a forca de preensao manual (FPM). O estudo foi do tipo transversal, com uma amostra de conveniencia composta por 106 idosas. As participantes foram classificadas quanto ao fenotipo de fragilidade. A FMR foi avaliada por meio da pressao inspiratoria maxima (PImax) e da pressao expiratoria maxima (PEmax). Foram encontradas diferencas significativas da FMR entre os grupos NF e F (PImax: p=0,001 e PEmax: p<0,001) e entre os grupos PF e F (PImax: p<0,001 e PEmax: p<0,001). Em relacao a FPM, foram observadas diferencas significativas entre todos os grupos (p<0,001). Houve correlacao entre FMR e FPM apenas no grupo fragil. Desta forma, a FPM pode ser importante na pratica clinica para diferenciar os subgrupos de fragilidade e identificar a perda de forca muscular, incluindo a perda da FMR.Correspondence to: Vanessa Amaral Mendonça – Rodovia MGT 367, km 583, 5000 – CEP: 39100-000 – Campus JK – Diamantina (MG), Brazil – E-mail: vaafisio@gmail.com Presentation: Apr. 2013 – Accepted for publication: Nov. 2013 – Financing source: none – Conflict of interests: nothing to declare – Presentation at a scientific event: SINTEGRA – 2012/ UFVJM, Diamantina (MG), Brazil – Approval at the Ethics Committee n. 056/11. ABSTRACT | The fragility consist in a tripod comprising: sarcopenia, immune dysregulation, and neuroendocrine dysfunction. Sarcopenia is defined as a decrease in strength and muscle power, so that the respiratory muscles are also affected. The aim was to compare respiratory muscle strength (RMS) in elderly community residents, classified as nonfrail (NF), pre frail (PF) and frail (F), and correlate RMS with the handgrip strength (HS). The study was cross-sectional, with a convenience sample of 106 elderly women. Participants were classified according to the phenotype of frailty. The RMS was assessed by maximal inspiratory pressure (MIP) and maximum expiratory pressure (MEP). Significant differences were found in RMS between groups NF and F (MIP: p=0.001 and MEP: p<0.001) and between groups PF and F (MIP: p<0.001 and MEP: p<0.001). In relation to HS, significant differences were observed between all groups (p<0.001). There was correlation between HS and RMS only in the frail group. Thus, the HS may be important in the clinical evaluation to differentiate subgroups of fragility and identify the loss of muscle strength, including the loss of RMS.

Comparación de la fuerza muscular respiratoria entre los subgrupos de fragilidad en añosas de la comunidad

A fragilidade e composta por um tripe constituido por: sarcopenia, disfuncao imunologica e desregulacao neuroendocrina. A sarcopenia e definida como uma diminuicao na forca e na potencia muscular, sendo que os musculos respiratorios tambem sao afetados. O objetivo foi comparar a forca muscular respiratoria (FMR) em idosas residentes na comunidade, classificadas como nao frageis (NF), pre-frageis (PF) e frageis (F) e correlacionar a FMR com a forca de preensao manual (FPM). O estudo foi do tipo transversal, com uma amostra de conveniencia composta por 106 idosas. As participantes foram classificadas quanto ao fenotipo de fragilidade. A FMR foi avaliada por meio da pressao inspiratoria maxima (PImax) e da pressao expiratoria maxima (PEmax). Foram encontradas diferencas significativas da FMR entre os grupos NF e F (PImax: p=0,001 e PEmax: p<0,001) e entre os grupos PF e F (PImax: p<0,001 e PEmax: p<0,001). Em relacao a FPM, foram observadas diferencas significativas entre todos os grupos (p<0,001). Houve correlacao entre FMR e FPM apenas no grupo fragil. Desta forma, a FPM pode ser importante na pratica clinica para diferenciar os subgrupos de fragilidade e identificar a perda de forca muscular, incluindo a perda da FMR.Correspondence to: Vanessa Amaral Mendonça – Rodovia MGT 367, km 583, 5000 – CEP: 39100-000 – Campus JK – Diamantina (MG), Brazil – E-mail: vaafisio@gmail.com Presentation: Apr. 2013 – Accepted for publication: Nov. 2013 – Financing source: none – Conflict of interests: nothing to declare – Presentation at a scientific event: SINTEGRA – 2012/ UFVJM, Diamantina (MG), Brazil – Approval at the Ethics Committee n. 056/11. ABSTRACT | The fragility consist in a tripod comprising: sarcopenia, immune dysregulation, and neuroendocrine dysfunction. Sarcopenia is defined as a decrease in strength and muscle power, so that the respiratory muscles are also affected. The aim was to compare respiratory muscle strength (RMS) in elderly community residents, classified as nonfrail (NF), pre frail (PF) and frail (F), and correlate RMS with the handgrip strength (HS). The study was cross-sectional, with a convenience sample of 106 elderly women. Participants were classified according to the phenotype of frailty. The RMS was assessed by maximal inspiratory pressure (MIP) and maximum expiratory pressure (MEP). Significant differences were found in RMS between groups NF and F (MIP: p=0.001 and MEP: p<0.001) and between groups PF and F (MIP: p<0.001 and MEP: p<0.001). In relation to HS, significant differences were observed between all groups (p<0.001). There was correlation between HS and RMS only in the frail group. Thus, the HS may be important in the clinical evaluation to differentiate subgroups of fragility and identify the loss of muscle strength, including the loss of RMS.

Comparação da força muscular respiratória entre os subgrupos de fragilidade em idosas da comunidade

A fragilidade e composta por um tripe constituido por: sarcopenia, disfuncao imunologica e desregulacao neuroendocrina. A sarcopenia e definida como uma diminuicao na forca e na potencia muscular, sendo que os musculos respiratorios tambem sao afetados. O objetivo foi comparar a forca muscular respiratoria (FMR) em idosas residentes na comunidade, classificadas como nao frageis (NF), pre-frageis (PF) e frageis (F) e correlacionar a FMR com a forca de preensao manual (FPM). O estudo foi do tipo transversal, com uma amostra de conveniencia composta por 106 idosas. As participantes foram classificadas quanto ao fenotipo de fragilidade. A FMR foi avaliada por meio da pressao inspiratoria maxima (PImax) e da pressao expiratoria maxima (PEmax). Foram encontradas diferencas significativas da FMR entre os grupos NF e F (PImax: p=0,001 e PEmax: p<0,001) e entre os grupos PF e F (PImax: p<0,001 e PEmax: p<0,001). Em relacao a FPM, foram observadas diferencas significativas entre todos os grupos (p<0,001). Houve correlacao entre FMR e FPM apenas no grupo fragil. Desta forma, a FPM pode ser importante na pratica clinica para diferenciar os subgrupos de fragilidade e identificar a perda de forca muscular, incluindo a perda da FMR.Correspondence to: Vanessa Amaral Mendonça – Rodovia MGT 367, km 583, 5000 – CEP: 39100-000 – Campus JK – Diamantina (MG), Brazil – E-mail: vaafisio@gmail.com Presentation: Apr. 2013 – Accepted for publication: Nov. 2013 – Financing source: none – Conflict of interests: nothing to declare – Presentation at a scientific event: SINTEGRA – 2012/ UFVJM, Diamantina (MG), Brazil – Approval at the Ethics Committee n. 056/11. ABSTRACT | The fragility consist in a tripod comprising: sarcopenia, immune dysregulation, and neuroendocrine dysfunction. Sarcopenia is defined as a decrease in strength and muscle power, so that the respiratory muscles are also affected. The aim was to compare respiratory muscle strength (RMS) in elderly community residents, classified as nonfrail (NF), pre frail (PF) and frail (F), and correlate RMS with the handgrip strength (HS). The study was cross-sectional, with a convenience sample of 106 elderly women. Participants were classified according to the phenotype of frailty. The RMS was assessed by maximal inspiratory pressure (MIP) and maximum expiratory pressure (MEP). Significant differences were found in RMS between groups NF and F (MIP: p=0.001 and MEP: p<0.001) and between groups PF and F (MIP: p<0.001 and MEP: p<0.001). In relation to HS, significant differences were observed between all groups (p<0.001). There was correlation between HS and RMS only in the frail group. Thus, the HS may be important in the clinical evaluation to differentiate subgroups of fragility and identify the loss of muscle strength, including the loss of RMS.