The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform
Rachel Levy - One of the best experts on this subject based on the ideXlab platform.
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Hypoparathyroidism, Retardation, and Dysmorphism Syndrome: Impaired Early Growth and Increased Susceptibility to Severe Infections Due to Hyposplenism and Impaired Polymorphonuclear Cell Functions
Pediatric Research, 2007Co-Authors: Eli Hershkovitz, Ilia Rozin, Yehuda Limony, Haim Golan, Nurit Hadad, Rafael Gorodischer, Rachel LevyAbstract:Hypoparathyroidism, retardation, and dysmorphism (HRD) syndrome is the first reported disease caused by a defect in the tubulin folding and assembly pathway. We aimed to summarize our experience with a cohort of patients with HRD, analyze their growth, and evaluate patients' Polymorphonuclear Cell (PMN) functions. The records of 22 HRD patients in a single medical center were reviewed. Growth during infancy and early childhood were analyzed by the Infancy-Childhood-Puberty (ICP) growth model. PMN functions were compared with healthy controls. Twelve patients died and many hospitalizations due to infections and convulsions were recorded. Growth measurements, expressed as weight and height SD scores in boys at a mean age of 4 y were –13.1 ± 3.8 and –8.7 ± 1 and –16.6 ± 4.4 and –9.5 ± 2.4, respectively, in girls at a mean age of 6.4 y. Chemotactic migration, random migration, and phagocytosis of PMN from HRD patients were significantly lower than that of PMN from healthy controls. No significant differences were found in superoxide production of PMN from patients compared with controls. Functional hyposplenism has been demonstrated in most of the studied patients. The defect in the tubulin folding and assembly pathway, previously described in HRD, has grave consequences on growth and PMN functions.
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hypoparathyroidism retardation and dysmorphism syndrome impaired early growth and increased susceptibility to severe infections due to hyposplenism and impaired Polymorphonuclear Cell functions
Pediatric Research, 2007Co-Authors: Eli Hershkovitz, Ilia Rozin, Yehuda Limony, Haim Golan, Nurit Hadad, Rafael Gorodischer, Rachel LevyAbstract:Hypoparathyroidism, retardation, and dysmorphism (HRD) syndrome is the first reported disease caused by a defect in the tubulin folding and assembly pathway. We aimed to summarize our experience with a cohort of patients with HRD, analyze their growth, and evaluate patients' Polymorphonuclear Cell (PMN) functions. The records of 22 HRD patients in a single medical center were reviewed. Growth during infancy and early childhood were analyzed by the Infancy-Childhood-Puberty (ICP) growth model. PMN functions were compared with healthy controls. Twelve patients died and many hospitalizations due to infections and convulsions were recorded. Growth measurements, expressed as weight and height SD scores in boys at a mean age of 4 y were -13.1 3.8 and -8.7 1 and -16.6 4.4 and -9.5 2.4, respectively, in girls at a mean age of 6.4 y. Chemotactic migration, random migration, and phagocytosis of PMN from HRD patients were significantly lower than that of PMN from healthy controls. No significant differences were found in superoxide production of PMN from patients compared with controls. Functional hyposplenism has been demonstrated in most of the studied patients. The defect in the tubulin folding and assembly pathway, previously described in HRD, has grave consequences on growth and PMN functions. (Pediatr Res 62: 505-509, 2007)
Emmanuel Le Poul - One of the best experts on this subject based on the ideXlab platform.
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functional characterization of human receptors for short chain fatty acids and their role in Polymorphonuclear Cell activation
Journal of Biological Chemistry, 2003Co-Authors: Emmanuel Le Poul, Cecile Loison, Sofie Struyf, Jeanyves Springael, Vincent Lannoy, Marieeve Decobecq, Stephane Brezillon, Vincent Dupriez, Gilbert Vassart, Jozef Van DammeAbstract:Short chain fatty acids (SCFAs), including acetate, propionate, and butyrate, are produced at high concentration by bacteria in the gut and subsequently released in the bloodstream. Basal acetate concentrations in the blood (about 100 microm) can further increase to millimolar concentrations following alcohol intake. It was known previously that SCFAs can activate leukocytes, particularly neutrophils. In the present work, we have identified two previously orphan G protein-coupled receptors, GPR41 and GPR43, as receptors for SCFAs. Propionate was the most potent agonist for both GPR41 and GPR43. Acetate was more selective for GPR43, whereas butyrate and isobutyrate were more active on GPR41. The two receptors were coupled to inositol 1,4,5-trisphosphate formation, intraCellular Ca2+ release, ERK1/2 activation, and inhibition of cAMP accumulation. They exhibited, however, a differential coupling to G proteins; GPR41 coupled exclusively though the Pertussis toxin-sensitive Gi/o family, whereas GPR43 displayed a dual coupling through Gi/o and Pertussis toxin-insensitive Gq protein families. The broad expression profile of GPR41 in a number of tissues does not allow us to infer clear hypotheses regarding its biological functions. In contrast, the highly selective expression of GPR43 in leukocytes, particularly Polymorphonuclear Cells, suggests a role in the recruitment of these Cell populations toward sites of bacterial infection. The pharmacology of GPR43 matches indeed the effects of SCFAs on neutrophils, in terms of intraCellular Ca2+ release and chemotaxis. Such a neutrophil-specific SCFA receptor is potentially involved in the development of a variety of diseases characterized by either excessive or inefficient neutrophil recruitment and activation, such as inflammatory bowel diseases or alcoholism-associated immune depression. GPR43 might therefore constitute a target allowing us to modulate immune responses in these pathological situations.
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functional characterization of human receptors for short chain fatty acids and their role in Polymorphonuclear Cell activation
Journal of Biological Chemistry, 2003Co-Authors: Emmanuel Le Poul, Cecile Loison, Sofie Struyf, Jeanyves Springael, Vincent Lannoy, Marieeve Decobecq, Stephane Brezillon, Vincent Dupriez, Gilbert Vassart, Jozef Van DammeAbstract:Short chain fatty acids (SCFAs), including acetate, propionate, and butyrate, are produced at high concentration by bacteria in the gut and subsequently released in the bloodstream. Basal acetate concentrations in the blood (about 100 microm) can further increase to millimolar concentrations following alcohol intake. It was known previously that SCFAs can activate leukocytes, particularly neutrophils. In the present work, we have identified two previously orphan G protein-coupled receptors, GPR41 and GPR43, as receptors for SCFAs. Propionate was the most potent agonist for both GPR41 and GPR43. Acetate was more selective for GPR43, whereas butyrate and isobutyrate were more active on GPR41. The two receptors were coupled to inositol 1,4,5-trisphosphate formation, intraCellular Ca2+ release, ERK1/2 activation, and inhibition of cAMP accumulation. They exhibited, however, a differential coupling to G proteins; GPR41 coupled exclusively though the Pertussis toxin-sensitive Gi/o family, whereas GPR43 displayed a dual coupling through Gi/o and Pertussis toxin-insensitive Gq protein families. The broad expression profile of GPR41 in a number of tissues does not allow us to infer clear hypotheses regarding its biological functions. In contrast, the highly selective expression of GPR43 in leukocytes, particularly Polymorphonuclear Cells, suggests a role in the recruitment of these Cell populations toward sites of bacterial infection. The pharmacology of GPR43 matches indeed the effects of SCFAs on neutrophils, in terms of intraCellular Ca2+ release and chemotaxis. Such a neutrophil-specific SCFA receptor is potentially involved in the development of a variety of diseases characterized by either excessive or inefficient neutrophil recruitment and activation, such as inflammatory bowel diseases or alcoholism-associated immune depression. GPR43 might therefore constitute a target allowing us to modulate immune responses in these pathological situations.
Jozef Van Damme - One of the best experts on this subject based on the ideXlab platform.
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functional characterization of human receptors for short chain fatty acids and their role in Polymorphonuclear Cell activation
Journal of Biological Chemistry, 2003Co-Authors: Emmanuel Le Poul, Cecile Loison, Sofie Struyf, Jeanyves Springael, Vincent Lannoy, Marieeve Decobecq, Stephane Brezillon, Vincent Dupriez, Gilbert Vassart, Jozef Van DammeAbstract:Short chain fatty acids (SCFAs), including acetate, propionate, and butyrate, are produced at high concentration by bacteria in the gut and subsequently released in the bloodstream. Basal acetate concentrations in the blood (about 100 microm) can further increase to millimolar concentrations following alcohol intake. It was known previously that SCFAs can activate leukocytes, particularly neutrophils. In the present work, we have identified two previously orphan G protein-coupled receptors, GPR41 and GPR43, as receptors for SCFAs. Propionate was the most potent agonist for both GPR41 and GPR43. Acetate was more selective for GPR43, whereas butyrate and isobutyrate were more active on GPR41. The two receptors were coupled to inositol 1,4,5-trisphosphate formation, intraCellular Ca2+ release, ERK1/2 activation, and inhibition of cAMP accumulation. They exhibited, however, a differential coupling to G proteins; GPR41 coupled exclusively though the Pertussis toxin-sensitive Gi/o family, whereas GPR43 displayed a dual coupling through Gi/o and Pertussis toxin-insensitive Gq protein families. The broad expression profile of GPR41 in a number of tissues does not allow us to infer clear hypotheses regarding its biological functions. In contrast, the highly selective expression of GPR43 in leukocytes, particularly Polymorphonuclear Cells, suggests a role in the recruitment of these Cell populations toward sites of bacterial infection. The pharmacology of GPR43 matches indeed the effects of SCFAs on neutrophils, in terms of intraCellular Ca2+ release and chemotaxis. Such a neutrophil-specific SCFA receptor is potentially involved in the development of a variety of diseases characterized by either excessive or inefficient neutrophil recruitment and activation, such as inflammatory bowel diseases or alcoholism-associated immune depression. GPR43 might therefore constitute a target allowing us to modulate immune responses in these pathological situations.
Jozef Van Damme - One of the best experts on this subject based on the ideXlab platform.
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functional characterization of human receptors for short chain fatty acids and their role in Polymorphonuclear Cell activation
Journal of Biological Chemistry, 2003Co-Authors: Emmanuel Le Poul, Cecile Loison, Sofie Struyf, Jeanyves Springael, Vincent Lannoy, Marieeve Decobecq, Stephane Brezillon, Vincent Dupriez, Gilbert Vassart, Jozef Van DammeAbstract:Short chain fatty acids (SCFAs), including acetate, propionate, and butyrate, are produced at high concentration by bacteria in the gut and subsequently released in the bloodstream. Basal acetate concentrations in the blood (about 100 microm) can further increase to millimolar concentrations following alcohol intake. It was known previously that SCFAs can activate leukocytes, particularly neutrophils. In the present work, we have identified two previously orphan G protein-coupled receptors, GPR41 and GPR43, as receptors for SCFAs. Propionate was the most potent agonist for both GPR41 and GPR43. Acetate was more selective for GPR43, whereas butyrate and isobutyrate were more active on GPR41. The two receptors were coupled to inositol 1,4,5-trisphosphate formation, intraCellular Ca2+ release, ERK1/2 activation, and inhibition of cAMP accumulation. They exhibited, however, a differential coupling to G proteins; GPR41 coupled exclusively though the Pertussis toxin-sensitive Gi/o family, whereas GPR43 displayed a dual coupling through Gi/o and Pertussis toxin-insensitive Gq protein families. The broad expression profile of GPR41 in a number of tissues does not allow us to infer clear hypotheses regarding its biological functions. In contrast, the highly selective expression of GPR43 in leukocytes, particularly Polymorphonuclear Cells, suggests a role in the recruitment of these Cell populations toward sites of bacterial infection. The pharmacology of GPR43 matches indeed the effects of SCFAs on neutrophils, in terms of intraCellular Ca2+ release and chemotaxis. Such a neutrophil-specific SCFA receptor is potentially involved in the development of a variety of diseases characterized by either excessive or inefficient neutrophil recruitment and activation, such as inflammatory bowel diseases or alcoholism-associated immune depression. GPR43 might therefore constitute a target allowing us to modulate immune responses in these pathological situations.
Marieeve Decobecq - One of the best experts on this subject based on the ideXlab platform.
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functional characterization of human receptors for short chain fatty acids and their role in Polymorphonuclear Cell activation
Journal of Biological Chemistry, 2003Co-Authors: Emmanuel Le Poul, Cecile Loison, Sofie Struyf, Jeanyves Springael, Vincent Lannoy, Marieeve Decobecq, Stephane Brezillon, Vincent Dupriez, Gilbert Vassart, Jozef Van DammeAbstract:Short chain fatty acids (SCFAs), including acetate, propionate, and butyrate, are produced at high concentration by bacteria in the gut and subsequently released in the bloodstream. Basal acetate concentrations in the blood (about 100 microm) can further increase to millimolar concentrations following alcohol intake. It was known previously that SCFAs can activate leukocytes, particularly neutrophils. In the present work, we have identified two previously orphan G protein-coupled receptors, GPR41 and GPR43, as receptors for SCFAs. Propionate was the most potent agonist for both GPR41 and GPR43. Acetate was more selective for GPR43, whereas butyrate and isobutyrate were more active on GPR41. The two receptors were coupled to inositol 1,4,5-trisphosphate formation, intraCellular Ca2+ release, ERK1/2 activation, and inhibition of cAMP accumulation. They exhibited, however, a differential coupling to G proteins; GPR41 coupled exclusively though the Pertussis toxin-sensitive Gi/o family, whereas GPR43 displayed a dual coupling through Gi/o and Pertussis toxin-insensitive Gq protein families. The broad expression profile of GPR41 in a number of tissues does not allow us to infer clear hypotheses regarding its biological functions. In contrast, the highly selective expression of GPR43 in leukocytes, particularly Polymorphonuclear Cells, suggests a role in the recruitment of these Cell populations toward sites of bacterial infection. The pharmacology of GPR43 matches indeed the effects of SCFAs on neutrophils, in terms of intraCellular Ca2+ release and chemotaxis. Such a neutrophil-specific SCFA receptor is potentially involved in the development of a variety of diseases characterized by either excessive or inefficient neutrophil recruitment and activation, such as inflammatory bowel diseases or alcoholism-associated immune depression. GPR43 might therefore constitute a target allowing us to modulate immune responses in these pathological situations.
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functional characterization of human receptors for short chain fatty acids and their role in Polymorphonuclear Cell activation
Journal of Biological Chemistry, 2003Co-Authors: Emmanuel Le Poul, Cecile Loison, Sofie Struyf, Jeanyves Springael, Vincent Lannoy, Marieeve Decobecq, Stephane Brezillon, Vincent Dupriez, Gilbert Vassart, Jozef Van DammeAbstract:Short chain fatty acids (SCFAs), including acetate, propionate, and butyrate, are produced at high concentration by bacteria in the gut and subsequently released in the bloodstream. Basal acetate concentrations in the blood (about 100 microm) can further increase to millimolar concentrations following alcohol intake. It was known previously that SCFAs can activate leukocytes, particularly neutrophils. In the present work, we have identified two previously orphan G protein-coupled receptors, GPR41 and GPR43, as receptors for SCFAs. Propionate was the most potent agonist for both GPR41 and GPR43. Acetate was more selective for GPR43, whereas butyrate and isobutyrate were more active on GPR41. The two receptors were coupled to inositol 1,4,5-trisphosphate formation, intraCellular Ca2+ release, ERK1/2 activation, and inhibition of cAMP accumulation. They exhibited, however, a differential coupling to G proteins; GPR41 coupled exclusively though the Pertussis toxin-sensitive Gi/o family, whereas GPR43 displayed a dual coupling through Gi/o and Pertussis toxin-insensitive Gq protein families. The broad expression profile of GPR41 in a number of tissues does not allow us to infer clear hypotheses regarding its biological functions. In contrast, the highly selective expression of GPR43 in leukocytes, particularly Polymorphonuclear Cells, suggests a role in the recruitment of these Cell populations toward sites of bacterial infection. The pharmacology of GPR43 matches indeed the effects of SCFAs on neutrophils, in terms of intraCellular Ca2+ release and chemotaxis. Such a neutrophil-specific SCFA receptor is potentially involved in the development of a variety of diseases characterized by either excessive or inefficient neutrophil recruitment and activation, such as inflammatory bowel diseases or alcoholism-associated immune depression. GPR43 might therefore constitute a target allowing us to modulate immune responses in these pathological situations.