The aim of this study was to test if previous ingestion of compounds containing resveratrol or hydroxytyrosol, followed by an exhausting hand grip exercise, could induce an acute post-exercise increase in brachial blo...The aim of this study was to test if previous ingestion of compounds containing resveratrol or hydroxytyrosol, followed by an exhausting hand grip exercise, could induce an acute post-exercise increase in brachial blood flow. Six healthy subjects (three males and three females, 35 ± 7 years), 60 minutes after ingestion of a capsule containing 200 mg of resveratrol or 30 ml of extra virgin olive oil enriched with tyrosol, oleuropein and hydroxytyrosol, performed a hand grip exercise equal to half of their maximum strength until they were no longer able to express the same force (2-day interval between tests). The nonparametric Wilcoxon signed rank test was used for statistical evaluations. Brachial artery blood flow (Fba) and both blood velocity (Vba) and artery diameter (Dba) were assessed immediately after exercise cessation by means of colour Doppler ultrasound. After ingestion of the oil mixture the post-exercise value of Fba median was 2.4 times higher than that after ingestion of the resveratrol compound (P = 0.03), and also the Vba median concerning the hydroxytyrosol was 1.9 times higher than that of the resveratrol (P = 0.03). Both functional foods did not lead to a significant difference in the Dba medians. These results indicate that hydroxytyrosol, but not resveratrol, may be an effective adjuvant of recreational or agonistic, long-lasting sports performances, thanks to the powerful blood flow increment which can be obtained as soon as one hour from its oral intake.展开更多
Natural killer cells (NK) are a group of peripheral blood lymphocytes which display cytotoxic activity against a wide range of tumour cells. They are a consistent part of the inflammatory response that is activated wh...Natural killer cells (NK) are a group of peripheral blood lymphocytes which display cytotoxic activity against a wide range of tumour cells. They are a consistent part of the inflammatory response that is activated when either internal or external injuries occur as they are able to synthesize perforins. An important role is played by NK cells in the host defence against tumours without expressing any antigen-binding recaptor in their membrane which, however, distinguish T and B lymphocytes. NK activity appears early in the immune response, thus providing immediate protection during the time required for the activation and proliferation of cytotoxic T lymphocytes and for their differentiation into functional cells. Even though much research regarding the effects of aerobic training exercise on NK cell numbers and function, there appears to be much controversy regarding its effect. NK cells are rapidly mobilized into circulation in response to acute exercise, most likely by increased shear stress and catecholamine-induced down-regulation of adhesion molecule expression. However, tissue injury and inflammation which often accompanies strenuous exercise have been associated to post-exercise NK cell suppression. Scientific evidence indicates exercise-induced changes in NK cell redistribution and function should be strongly influenced by stress hormones including catecholamines, cortisol and prolactin as well as by soluble mediators such as cytokines and prostaglandins. The role of exercise therapy in cancer patients and survivors rehabilitation is becoming increasingly important as it is thought to modulate immunity and inflammation. However, more knowledge about the effects of exercise on immune function in these patients is needed.展开更多
文摘The aim of this study was to test if previous ingestion of compounds containing resveratrol or hydroxytyrosol, followed by an exhausting hand grip exercise, could induce an acute post-exercise increase in brachial blood flow. Six healthy subjects (three males and three females, 35 ± 7 years), 60 minutes after ingestion of a capsule containing 200 mg of resveratrol or 30 ml of extra virgin olive oil enriched with tyrosol, oleuropein and hydroxytyrosol, performed a hand grip exercise equal to half of their maximum strength until they were no longer able to express the same force (2-day interval between tests). The nonparametric Wilcoxon signed rank test was used for statistical evaluations. Brachial artery blood flow (Fba) and both blood velocity (Vba) and artery diameter (Dba) were assessed immediately after exercise cessation by means of colour Doppler ultrasound. After ingestion of the oil mixture the post-exercise value of Fba median was 2.4 times higher than that after ingestion of the resveratrol compound (P = 0.03), and also the Vba median concerning the hydroxytyrosol was 1.9 times higher than that of the resveratrol (P = 0.03). Both functional foods did not lead to a significant difference in the Dba medians. These results indicate that hydroxytyrosol, but not resveratrol, may be an effective adjuvant of recreational or agonistic, long-lasting sports performances, thanks to the powerful blood flow increment which can be obtained as soon as one hour from its oral intake.
文摘Natural killer cells (NK) are a group of peripheral blood lymphocytes which display cytotoxic activity against a wide range of tumour cells. They are a consistent part of the inflammatory response that is activated when either internal or external injuries occur as they are able to synthesize perforins. An important role is played by NK cells in the host defence against tumours without expressing any antigen-binding recaptor in their membrane which, however, distinguish T and B lymphocytes. NK activity appears early in the immune response, thus providing immediate protection during the time required for the activation and proliferation of cytotoxic T lymphocytes and for their differentiation into functional cells. Even though much research regarding the effects of aerobic training exercise on NK cell numbers and function, there appears to be much controversy regarding its effect. NK cells are rapidly mobilized into circulation in response to acute exercise, most likely by increased shear stress and catecholamine-induced down-regulation of adhesion molecule expression. However, tissue injury and inflammation which often accompanies strenuous exercise have been associated to post-exercise NK cell suppression. Scientific evidence indicates exercise-induced changes in NK cell redistribution and function should be strongly influenced by stress hormones including catecholamines, cortisol and prolactin as well as by soluble mediators such as cytokines and prostaglandins. The role of exercise therapy in cancer patients and survivors rehabilitation is becoming increasingly important as it is thought to modulate immunity and inflammation. However, more knowledge about the effects of exercise on immune function in these patients is needed.
