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Alban Longchamp - One of the best experts on this subject based on the ideXlab platform.
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short term preoperative Protein Restriction attenuates vein graft disease via induction of cystathionine γ lyase
Cardiovascular Research, 2019Co-Authors: Kaspar Trocha, Peter Kip, Ming Tao, Michael R Macarthur, Humberto J Trevinovillarreal, Alban LongchampAbstract:Aims Therapies to prevent vein graft disease, a major problem in cardiovascular and lower extremity bypass surgeries, are currently lacking. Short-term preoperative Protein Restriction holds promise as an effective preconditioning method against surgical stress in rodent models, but whether it can improve vein graft patency after bypass surgery is undetermined. Here, we hypothesized that short-term Protein Restriction would limit vein graft disease via up-regulation of cystathionine γ-lyase and increased endogenous production of the cytoprotective gaseous signalling molecule hydrogen sulfide. Methods and results Low-density lipoProtein receptor knockout mice were preconditioned for 1 week on a high-fat high-cholesterol (HFHC) diet with or without Protein prior to left common carotid interposition vein graft surgery with caval veins from donor mice on corresponding diets. Both groups were returned to a complete HFHC diet post-operatively, and vein grafts analysed 4 or 28 days later. A novel global transgenic cystathionine γ-lyase overexpressing mouse model was also employed to study effects of genetic overexpression on graft patency. Protein Restriction decreased vein graft intimal/media+adventitia area and thickness ratios and intimal smooth muscle cell infiltration 28 days post-operatively, and neutrophil transmigration 4 days post-operatively. Protein Restriction increased cystathionine γ-lyase Protein expression in aortic and caval vein endothelial cells (ECs) and frequency of lung EC producing hydrogen sulfide. The cystathionine γ-lyase inhibitor propargylglycine abrogated Protein Restriction-mediated protection from graft failure and the increase in hydrogen sulfide-producing ECs, while cystathionine γ-lyase transgenic mice displayed increased hydrogen sulfide production capacity and were protected from vein graft disease independent of diet. Conclusion One week of Protein Restriction attenuates vein graft disease via increased cystathionine γ-lyase expression and hydrogen sulfide production, and decreased early inflammation. Dietary or pharmacological interventions to increase cystathionine γ-lyase or hydrogen sulfide may thus serve as new and practical strategies to improve vein graft durability.
Peter Kip - One of the best experts on this subject based on the ideXlab platform.
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short term preoperative Protein Restriction attenuates vein graft disease via induction of cystathionine γ lyase
Cardiovascular Research, 2019Co-Authors: Kaspar Trocha, Peter Kip, Ming Tao, Michael R Macarthur, Humberto J Trevinovillarreal, Alban LongchampAbstract:Aims Therapies to prevent vein graft disease, a major problem in cardiovascular and lower extremity bypass surgeries, are currently lacking. Short-term preoperative Protein Restriction holds promise as an effective preconditioning method against surgical stress in rodent models, but whether it can improve vein graft patency after bypass surgery is undetermined. Here, we hypothesized that short-term Protein Restriction would limit vein graft disease via up-regulation of cystathionine γ-lyase and increased endogenous production of the cytoprotective gaseous signalling molecule hydrogen sulfide. Methods and results Low-density lipoProtein receptor knockout mice were preconditioned for 1 week on a high-fat high-cholesterol (HFHC) diet with or without Protein prior to left common carotid interposition vein graft surgery with caval veins from donor mice on corresponding diets. Both groups were returned to a complete HFHC diet post-operatively, and vein grafts analysed 4 or 28 days later. A novel global transgenic cystathionine γ-lyase overexpressing mouse model was also employed to study effects of genetic overexpression on graft patency. Protein Restriction decreased vein graft intimal/media+adventitia area and thickness ratios and intimal smooth muscle cell infiltration 28 days post-operatively, and neutrophil transmigration 4 days post-operatively. Protein Restriction increased cystathionine γ-lyase Protein expression in aortic and caval vein endothelial cells (ECs) and frequency of lung EC producing hydrogen sulfide. The cystathionine γ-lyase inhibitor propargylglycine abrogated Protein Restriction-mediated protection from graft failure and the increase in hydrogen sulfide-producing ECs, while cystathionine γ-lyase transgenic mice displayed increased hydrogen sulfide production capacity and were protected from vein graft disease independent of diet. Conclusion One week of Protein Restriction attenuates vein graft disease via increased cystathionine γ-lyase expression and hydrogen sulfide production, and decreased early inflammation. Dietary or pharmacological interventions to increase cystathionine γ-lyase or hydrogen sulfide may thus serve as new and practical strategies to improve vein graft durability.
Kaspar Trocha - One of the best experts on this subject based on the ideXlab platform.
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short term preoperative Protein Restriction attenuates vein graft disease via induction of cystathionine γ lyase
Cardiovascular Research, 2019Co-Authors: Kaspar Trocha, Peter Kip, Ming Tao, Michael R Macarthur, Humberto J Trevinovillarreal, Alban LongchampAbstract:Aims Therapies to prevent vein graft disease, a major problem in cardiovascular and lower extremity bypass surgeries, are currently lacking. Short-term preoperative Protein Restriction holds promise as an effective preconditioning method against surgical stress in rodent models, but whether it can improve vein graft patency after bypass surgery is undetermined. Here, we hypothesized that short-term Protein Restriction would limit vein graft disease via up-regulation of cystathionine γ-lyase and increased endogenous production of the cytoprotective gaseous signalling molecule hydrogen sulfide. Methods and results Low-density lipoProtein receptor knockout mice were preconditioned for 1 week on a high-fat high-cholesterol (HFHC) diet with or without Protein prior to left common carotid interposition vein graft surgery with caval veins from donor mice on corresponding diets. Both groups were returned to a complete HFHC diet post-operatively, and vein grafts analysed 4 or 28 days later. A novel global transgenic cystathionine γ-lyase overexpressing mouse model was also employed to study effects of genetic overexpression on graft patency. Protein Restriction decreased vein graft intimal/media+adventitia area and thickness ratios and intimal smooth muscle cell infiltration 28 days post-operatively, and neutrophil transmigration 4 days post-operatively. Protein Restriction increased cystathionine γ-lyase Protein expression in aortic and caval vein endothelial cells (ECs) and frequency of lung EC producing hydrogen sulfide. The cystathionine γ-lyase inhibitor propargylglycine abrogated Protein Restriction-mediated protection from graft failure and the increase in hydrogen sulfide-producing ECs, while cystathionine γ-lyase transgenic mice displayed increased hydrogen sulfide production capacity and were protected from vein graft disease independent of diet. Conclusion One week of Protein Restriction attenuates vein graft disease via increased cystathionine γ-lyase expression and hydrogen sulfide production, and decreased early inflammation. Dietary or pharmacological interventions to increase cystathionine γ-lyase or hydrogen sulfide may thus serve as new and practical strategies to improve vein graft durability.
L. John Hoffer - One of the best experts on this subject based on the ideXlab platform.
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Effect of Protein Restriction on sulfur amino acid catabolism in insulin-dependent diabetes mellitus
American journal of physiology. Endocrinology and metabolism, 2002Co-Authors: Mazen J. Hamadeh, L. John HofferAbstract:Persons with conventionally treated insulin-dependent diabetes mellitus (IDDM) appear to be impaired in their ability to reduce fed-state urea production appropriately in response to dietary Protein Restriction (Hoffer LJ, Taveroff A, and Schiffrin A. Am J Physiol 272: E59-E67, 1997). To determine whether these conclusions apply to whole body sulfur amino acid (SAA) catabolism, we used samples from this protocol to measure daily urinary sulfate excretion and fed-state sulfate production after a high-Protein test meal before and after dietary Protein Restriction. Eight normal subjects and six IDDM subjects treated with twice-daily intermediate- and short-acting insulin consumed a mixed test meal containing 0.50 g Protein/kg after adaptation to 4 days of high Protein intake (1.28 g Protein/kg body wt) and again after 5 days of dietary Protein Restriction (0.044 g/kg). Adaptation to Protein Restriction decreased daily urinary sulfate and urea-N excretion by ∼80%. Over the first 24 h of Protein Restriction, urinary sulfate excretion decreased more than urea-N excretion for both the normal and IDDM subjects. Under conditions of a high prior Protein intake, fed-state sulfate production was normal for the IDDM subjects; Protein Restriction reduced fed-state sulfate production by 51% (normal subjects) and 59% (IDDM subjects; not significant). We conclude that whole body SAA metabolism is normal in conventionally treated IDDM before and after dietary Protein Restriction. SAA catabolism, as measured by fed-state sulfate production, may be a convenient and useful method to determine the extent of whole body Protein dysregulation in IDDM.
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Sulfate production depicts fed-state adaptation to Protein Restriction in humans.
American journal of physiology. Endocrinology and metabolism, 2001Co-Authors: Mazen J. Hamadeh, A Schiffrin, L. John HofferAbstract:One feature of the adaptation to dietary Protein Restriction is reduced urea production over the hours after consumption of a test meal of fixed composition. This adaptation is impaired in conventionally treated insulin-dependent diabetes mellitus (Hoffer LJ, Taveroff A, and Schiffrin A. Am J Physiol Endocrinol Metab 272: E59--E67, 1997). We have now tested the response to a test meal containing less Protein and included as a main outcome variable the production of sulfate, a specific indicator of sulfur amino acid catabolism. Six normal men consumed a mixed test meal containing 0.25 g Protein/kg and 10 kcal/kg while adapted to high (1.5 g x kg(-1) x day(-1)) and low (0.3 g. kg(-1) x day(-1)) Protein intakes. They followed the identical protocol twice. Six subjects with insulin-dependent diabetes consumed the test meal while adapted to their customary high-Protein diet. Adaptation to Protein Restriction reproducibly reduced 9-h cumulative postmeal urea N and S production by 22--29% and 49--52%, respectively (both P < 0.05). Similar results were obtained for a postmeal collection period of 6 h. The response of the diabetic subjects was normal. We conclude that reductions in postmeal urea and sulfate production after Protein Restriction are reproducible and are evident using a postmeal collection period as short as 6 h. Sulfate production effectively depicts fed-state adaptation to Protein Restriction.
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Sulfate production depicts fed-state adaptation to Protein Restriction in humans.
American Journal of Physiology-endocrinology and Metabolism, 2001Co-Authors: Mazen J. Hamadeh, A Schiffrin, L. John HofferAbstract:One feature of the adaptation to dietary Protein Restriction is reduced urea production over the hours after consumption of a test meal of fixed composition. This adaptation is impaired in conventi...
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Adaptation to Protein Restriction Is Impaired in Insulin-Dependent Diabetes Mellitus
Journal of Nutrition, 1998Co-Authors: L. John HofferAbstract:Although mild abnormalities of amino acid metabolism frequently exist in conventionally treated insulin-dependent diabetes mellitus (IDDM), their physiologic and nutritional importance is uncertain. We tested whether a tendency toward body N loss can be either masked or revealed in insulin-treated IDDM by changing the level of Protein in the diet. After adaptation to a Protein-free diet adequate in all other nutrients, obligatory urinary N excretion of intensively treated IDDM subjects was significantly greater than normal, indicating an impaired ability to recycle endogenous amino acids during Protein Restriction. When the preceding diet was high in Protein, urea N production after consumption of a mixed test meal matched the amount of N consumed for both normal and diabetic subjects. However, when the test meal was preceded by 5 d of Protein Restriction, conventionally treated IDDM subjects failed to adaptively reduce postprandial urea production as effectively as normal or intensively treated IDDM subjects. Thus, even during insulin treatment, the ability to maximally recycle endogenous amino acids is impaired in IDDM, as is the ability to adaptively increase dietary amino acid retention in response to Protein Restriction.
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Metabolic adaptation to Protein Restriction in insulin-dependent diabetes mellitus
American Journal of Physiology-Endocrinology and Metabolism, 1997Co-Authors: L. John Hoffer, Arlene Taveroff, A SchiffrinAbstract:Eight normal subjects, four subjects with intensively treated insulin-dependent diabetes mellitus (IDDM), and six subjects with conventionally treated IDDM consumed a test meal of 0.5 g Protein and 10 kcal per kg body weight, first while adapted to a conventional diet high in Protein, and then again after 5 days of dietary Protein Restriction. Metabolic N balance (N consumed minus urea production) and net Protein utilization were measured over the 9 h after consumption of the test meal, as was recovery in urea of 15N from a tracer dose of [15N]alanine included in each test meal. After the first test meal, N balance and net Protein utilization were similar and close to zero for all groups. After the second test meal, N balance and net Protein utilization became positive for all groups (P < 0.05) but significantly less so (P < 0.05) for the conventionally treated than for the normal and intensively treated diabetic subjects. 15N recovery in urea was reduced for all groups after the second test meal (P < 0.05) but probably less effectively (P < 0.09) for the conventionally treated diabetic subjects. Metabolic adaptation to Protein Restriction may be less effective than normal in conventionally treated IDDM.
Mazen J. Hamadeh - One of the best experts on this subject based on the ideXlab platform.
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Effect of Protein Restriction on sulfur amino acid catabolism in insulin-dependent diabetes mellitus
American journal of physiology. Endocrinology and metabolism, 2002Co-Authors: Mazen J. Hamadeh, L. John HofferAbstract:Persons with conventionally treated insulin-dependent diabetes mellitus (IDDM) appear to be impaired in their ability to reduce fed-state urea production appropriately in response to dietary Protein Restriction (Hoffer LJ, Taveroff A, and Schiffrin A. Am J Physiol 272: E59-E67, 1997). To determine whether these conclusions apply to whole body sulfur amino acid (SAA) catabolism, we used samples from this protocol to measure daily urinary sulfate excretion and fed-state sulfate production after a high-Protein test meal before and after dietary Protein Restriction. Eight normal subjects and six IDDM subjects treated with twice-daily intermediate- and short-acting insulin consumed a mixed test meal containing 0.50 g Protein/kg after adaptation to 4 days of high Protein intake (1.28 g Protein/kg body wt) and again after 5 days of dietary Protein Restriction (0.044 g/kg). Adaptation to Protein Restriction decreased daily urinary sulfate and urea-N excretion by ∼80%. Over the first 24 h of Protein Restriction, urinary sulfate excretion decreased more than urea-N excretion for both the normal and IDDM subjects. Under conditions of a high prior Protein intake, fed-state sulfate production was normal for the IDDM subjects; Protein Restriction reduced fed-state sulfate production by 51% (normal subjects) and 59% (IDDM subjects; not significant). We conclude that whole body SAA metabolism is normal in conventionally treated IDDM before and after dietary Protein Restriction. SAA catabolism, as measured by fed-state sulfate production, may be a convenient and useful method to determine the extent of whole body Protein dysregulation in IDDM.
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Sulfate production depicts fed-state adaptation to Protein Restriction in humans.
American journal of physiology. Endocrinology and metabolism, 2001Co-Authors: Mazen J. Hamadeh, A Schiffrin, L. John HofferAbstract:One feature of the adaptation to dietary Protein Restriction is reduced urea production over the hours after consumption of a test meal of fixed composition. This adaptation is impaired in conventionally treated insulin-dependent diabetes mellitus (Hoffer LJ, Taveroff A, and Schiffrin A. Am J Physiol Endocrinol Metab 272: E59--E67, 1997). We have now tested the response to a test meal containing less Protein and included as a main outcome variable the production of sulfate, a specific indicator of sulfur amino acid catabolism. Six normal men consumed a mixed test meal containing 0.25 g Protein/kg and 10 kcal/kg while adapted to high (1.5 g x kg(-1) x day(-1)) and low (0.3 g. kg(-1) x day(-1)) Protein intakes. They followed the identical protocol twice. Six subjects with insulin-dependent diabetes consumed the test meal while adapted to their customary high-Protein diet. Adaptation to Protein Restriction reproducibly reduced 9-h cumulative postmeal urea N and S production by 22--29% and 49--52%, respectively (both P < 0.05). Similar results were obtained for a postmeal collection period of 6 h. The response of the diabetic subjects was normal. We conclude that reductions in postmeal urea and sulfate production after Protein Restriction are reproducible and are evident using a postmeal collection period as short as 6 h. Sulfate production effectively depicts fed-state adaptation to Protein Restriction.
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Sulfate production depicts fed-state adaptation to Protein Restriction in humans.
American Journal of Physiology-endocrinology and Metabolism, 2001Co-Authors: Mazen J. Hamadeh, A Schiffrin, L. John HofferAbstract:One feature of the adaptation to dietary Protein Restriction is reduced urea production over the hours after consumption of a test meal of fixed composition. This adaptation is impaired in conventi...
