Background: Glucose is the main substrate for the generation of NADPH, the cofactor of the oxidative burst enzyme NADPH-oxidase of blood neutrophils. Changes in blood glucose are thus expected to modify the generation...Background: Glucose is the main substrate for the generation of NADPH, the cofactor of the oxidative burst enzyme NADPH-oxidase of blood neutrophils. Changes in blood glucose are thus expected to modify the generation of reactive oxygen species (ROS). The new blood ROS generation assay (BRGA) quantifies ROS changes induced by blood glucose concentrations as they are found in diabetes mellitus. Material and Methods: Citrated or EDTA blood of 6 healthy donors were analyzed in the BRGA: 10 μl sample in black polystyrene F-microwells (Brand 781608) were incubated in triplicate with 125 μl Hanks’ balanced salt solution, 40 μl 0 - 200 mM glucose in 0.9% NaCl (final added conc.: 0 - 41 mM;final basal glucose conc.: about4 mM), 10 μl5 mMluminol, and 10 μl zymosan A (final conc.: 1.9 μg/ml) in 0.9% NaCl. The plates were measured within 0 - 250 min (37℃) in a photons-multiplyer microtiter plate luminometer (LUmo) with an integration time of 1 s. Results: Up to about 30 min reaction time the mean ROS generation was 50% inhibited by about1 mMadded glucose (= approx. IC50). At ≥80 min reaction time (possibly necessary for full phosphorylation of glucose to glucose-6-phosphate (G6P), the substrate metabolized by G6P-dehydrogenase to generate NADPH, the cofactor of the NADPH-oxidase) the mean ROS generation approximately doubled at about1 mMadded glucose (= approx. SC200) in citrated blood. Discussion: Elevated glucose concentrations not only increase systemic thrombin generation, they can also diminish cellular fibrinolysis and increase systemic inflammation, resulting in a chronic pro-thrombotic state. The fascinating importance of NADPH-oxidases not only in phagocytes but also in the beta cells of pancreas points towards a new pathogenesis explication of diabetes mellitus type 1: whatever stimulus (e.g. a pancreas-tropic virus) could activate the beta cell’s autodestructive NADPH-oxidase.展开更多
The sexual maturation in all mammals is the period in which the quiescent gonads are activated by gonadotropins from anterior pituitary, increasing the secretion of sexual hormones. Sexual maturation it is also relate...The sexual maturation in all mammals is the period in which the quiescent gonads are activated by gonadotropins from anterior pituitary, increasing the secretion of sexual hormones. Sexual maturation it is also related with the development of several other body features such as body mass and maturation of the circulatory, skeletal and hematopoietic systems. The aim of the present study was to evaluate the function of neutrophils submitted to in vivo lower and higher concentration of testosterone (sexually immature: 60 days and sexually mature: 90 days). Using different approaches we evaluated cell viability and function and gene expression in rat neutrophils from 60 and 90 days-old animals. Neutrophils from 90 days-old rats showed a decrease in phagocytic and fungicidal capacity, without change in cellular viability. Additionally, we verified that sexual maturation induced increase in production of reactive oxygen and nitrogen species (RONS) and also in TNF-α, IL-6 and IL-10 cytokines. In conclusion, our data suggest that increase in testosterone levels induced significant alteration in neutrophil function, impairing phagocytic capacity.展开更多
The renin-angiotensin system(RAS)was classically considered a circulating hormonal system that regulates blood pressure.However,different tissues and organs,including the brain,have a local paracrine RAS.Mutual regula...The renin-angiotensin system(RAS)was classically considered a circulating hormonal system that regulates blood pressure.However,different tissues and organs,including the brain,have a local paracrine RAS.Mutual regulation between the dopaminergic system and RAS has been observed in several tissues.Dysregulation of these interactions leads to renal and cardiovascular diseases,as well as progression of dopaminergic neuron degeneration in a major brain center of dopamine/angiotensin interaction such as the nigrostriatal system.A decrease in the dopaminergic function induces upregulation of the angiotensin type-1(AT1)receptor activity,leading to recovery of dopamine levels.However,AT1 receptor overactivity in dopaminergic neurons and microglial cells upregulates the cellular NADPH-oxidase-superoxide axis and Ca^(2+)release,which mediate several key events in oxidative stress,neuroinflammation,andα-synuclein aggregation,involved in Parkinson’s disease(PD)pathogenesis.An intraneuronal antioxidative/anti-inflammatory RAS counteracts the effects of the pro-oxidative AT1 receptor overactivity.Consistent with this,an imbalance in RAS activity towards the pro-oxidative/pro-inflammatory AT1 receptor axis has been observed in the substantia nigra and striatum of several animal models of high vulnerability to dopaminergic degeneration.Interestingly,autoantibodies against angiotensin-converting enzyme 2 and AT1 receptors are increased in PD models and PD patients and contribute to blood-brain barrier(BBB)dysregulation and nigrostriatal pro-inflammatory RAS upregulation.Therapeutic strategies addressed to the modulation of brain RAS,by AT1 receptor blockers(ARBs)and/or activation of the antioxidative axis(AT2,Mas receptors),may be neuroprotective for individuals with a high risk of developing PD or in prodromal stages of PD to reduce progression of the disease.展开更多
文摘Background: Glucose is the main substrate for the generation of NADPH, the cofactor of the oxidative burst enzyme NADPH-oxidase of blood neutrophils. Changes in blood glucose are thus expected to modify the generation of reactive oxygen species (ROS). The new blood ROS generation assay (BRGA) quantifies ROS changes induced by blood glucose concentrations as they are found in diabetes mellitus. Material and Methods: Citrated or EDTA blood of 6 healthy donors were analyzed in the BRGA: 10 μl sample in black polystyrene F-microwells (Brand 781608) were incubated in triplicate with 125 μl Hanks’ balanced salt solution, 40 μl 0 - 200 mM glucose in 0.9% NaCl (final added conc.: 0 - 41 mM;final basal glucose conc.: about4 mM), 10 μl5 mMluminol, and 10 μl zymosan A (final conc.: 1.9 μg/ml) in 0.9% NaCl. The plates were measured within 0 - 250 min (37℃) in a photons-multiplyer microtiter plate luminometer (LUmo) with an integration time of 1 s. Results: Up to about 30 min reaction time the mean ROS generation was 50% inhibited by about1 mMadded glucose (= approx. IC50). At ≥80 min reaction time (possibly necessary for full phosphorylation of glucose to glucose-6-phosphate (G6P), the substrate metabolized by G6P-dehydrogenase to generate NADPH, the cofactor of the NADPH-oxidase) the mean ROS generation approximately doubled at about1 mMadded glucose (= approx. SC200) in citrated blood. Discussion: Elevated glucose concentrations not only increase systemic thrombin generation, they can also diminish cellular fibrinolysis and increase systemic inflammation, resulting in a chronic pro-thrombotic state. The fascinating importance of NADPH-oxidases not only in phagocytes but also in the beta cells of pancreas points towards a new pathogenesis explication of diabetes mellitus type 1: whatever stimulus (e.g. a pancreas-tropic virus) could activate the beta cell’s autodestructive NADPH-oxidase.
文摘The sexual maturation in all mammals is the period in which the quiescent gonads are activated by gonadotropins from anterior pituitary, increasing the secretion of sexual hormones. Sexual maturation it is also related with the development of several other body features such as body mass and maturation of the circulatory, skeletal and hematopoietic systems. The aim of the present study was to evaluate the function of neutrophils submitted to in vivo lower and higher concentration of testosterone (sexually immature: 60 days and sexually mature: 90 days). Using different approaches we evaluated cell viability and function and gene expression in rat neutrophils from 60 and 90 days-old animals. Neutrophils from 90 days-old rats showed a decrease in phagocytic and fungicidal capacity, without change in cellular viability. Additionally, we verified that sexual maturation induced increase in production of reactive oxygen and nitrogen species (RONS) and also in TNF-α, IL-6 and IL-10 cytokines. In conclusion, our data suggest that increase in testosterone levels induced significant alteration in neutrophil function, impairing phagocytic capacity.
基金supported by Spanish Ministry of Science and Innovation(PID2021-126848NB-I00,PLEC2022-009401)Instituto de Salud CarlosⅢ(RD21/0017/0031+1 种基金PI20/00345,and CIBERNED)Galician Government(XUGA,ED431C 2022/41),and FEDER(Regional European Development Fund).
文摘The renin-angiotensin system(RAS)was classically considered a circulating hormonal system that regulates blood pressure.However,different tissues and organs,including the brain,have a local paracrine RAS.Mutual regulation between the dopaminergic system and RAS has been observed in several tissues.Dysregulation of these interactions leads to renal and cardiovascular diseases,as well as progression of dopaminergic neuron degeneration in a major brain center of dopamine/angiotensin interaction such as the nigrostriatal system.A decrease in the dopaminergic function induces upregulation of the angiotensin type-1(AT1)receptor activity,leading to recovery of dopamine levels.However,AT1 receptor overactivity in dopaminergic neurons and microglial cells upregulates the cellular NADPH-oxidase-superoxide axis and Ca^(2+)release,which mediate several key events in oxidative stress,neuroinflammation,andα-synuclein aggregation,involved in Parkinson’s disease(PD)pathogenesis.An intraneuronal antioxidative/anti-inflammatory RAS counteracts the effects of the pro-oxidative AT1 receptor overactivity.Consistent with this,an imbalance in RAS activity towards the pro-oxidative/pro-inflammatory AT1 receptor axis has been observed in the substantia nigra and striatum of several animal models of high vulnerability to dopaminergic degeneration.Interestingly,autoantibodies against angiotensin-converting enzyme 2 and AT1 receptors are increased in PD models and PD patients and contribute to blood-brain barrier(BBB)dysregulation and nigrostriatal pro-inflammatory RAS upregulation.Therapeutic strategies addressed to the modulation of brain RAS,by AT1 receptor blockers(ARBs)and/or activation of the antioxidative axis(AT2,Mas receptors),may be neuroprotective for individuals with a high risk of developing PD or in prodromal stages of PD to reduce progression of the disease.
