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Kenneth C. Welch - One of the best experts on this subject based on the ideXlab platform.
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Glucose transporter expression and Regulation following a fast in the ruby-throated hummingbird, Archilochus colubris.
The Journal of Experimental Biology, 2020Co-Authors: Raafay Syed Ali, Morag F. Dick, Saad Muhammad, Dylan Sarver, Lily Hou, G. William Wong, Kenneth C. WelchAbstract:ABSTRACT Hummingbirds, subsisting almost exclusively on nectar Sugar, face extreme challenges to Blood Sugar Regulation. The capacity for transmembrane Sugar transport is mediated by the activity of facilitative glucose transporters (GLUTs) and their localisation to the plasma membrane (PM). In this study, we determined the relative protein abundance of GLUT1, GLUT2, GLUT3 and GLUT5 via immunoblot using custom-designed antibodies in whole-tissue homogenates and PM fractions of flight muscle, heart and liver of ruby-throated hummingbirds (Archilochus colubris). The GLUTs examined were detected in nearly all tissues tested. Hepatic GLUT1 was minimally present in whole-tissue homogenates and absent win PM fractions. GLUT5 was expressed in flight muscles at levels comparable to those of the liver, consistent with the hypothesised uniquely high fructose uptake and oxidation capacity of hummingbird flight muscles. To assess GLUT Regulation, we fed ruby-throated hummingbirds 1 mol l−1 sucrose ad libitum for 24 h followed by either 1 h of fasting or continued feeding until sampling. We measured relative GLUT abundance and concentration of circulating Sugars. Blood fructose concentration in fasted hummingbirds declined (∼5 mmol l−1 to ∼0.18 mmol l−1), while fructose-transporting GLUT2 and GLUT5 abundance did not change in PM fractions. Blood glucose concentrations remained elevated in fed and fasted hummingbirds (∼30 mmol l−1), while glucose-transporting GLUT1 and GLUT3 in flight muscle and liver PM fractions, respectively, declined in fasted birds. Our results suggest that glucose uptake capacity is dynamically reduced in response to fasting, allowing for maintenance of elevated Blood glucose levels, while fructose uptake capacity remains constitutively elevated promoting depletion of Blood total fructose within the first hour of a fast.
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Glucose transporter expression and Regulation following a fast in the ruby-throated hummingbird, Archilochus colubris.
2020Co-Authors: Raafay Syed Ali, Morag F. Dick, Saad Muhammad, Dylan Sarver, G. William Wong, Kenneth C. WelchAbstract:Hummingbirds subsist almost exclusively on nectar Sugar and face extreme challenges Blood Sugar Regulation. Transmembrane Sugar transport is mediated by facilitative glucose transporters (GLUTs) and the capacity for Sugar transport is dependent on both the activity of GLUTs and their localisation to the plasma membrane (PM). In this study, we determined the relative protein abundance in whole-tissue (WT) homogenates and PM fractions via immunoblot using custom antibodies for GLUT1, GLUT2, GLUT3, and GLUT5 in flight muscle, heart, and, liver of ruby-throated hummingbirds (Archilochus colubris). GLUTs examined were detected in nearly all tissues tested. Hepatic GLUT1 was minimally present in WT homogenates and absent in PM fractions. GLUT5 was expressed in hummingbird flight muscles at levels comparable to that of their liver, consistent with the hypothesised uniquely high fructose-uptake and oxidation capacity of this tissue. To assess GLUT Regulation, we fed ruby-throated hummingbirds 1M sucrose ad libitum for 24 hours followed by either 1 hour of fasting or continued ad libitum feeding until sampling. We measured relative GLUT abundance and concentrations of circulating Sugars. Blood fructose concentration in fasted hummingbirds declined from ~5mM to ~0.18mM, while fructose-transporting PM GLUT2 and PM GLUT5 did not change in abundance. Blood glucose concentrations remained elevated in both fed and fasted hummingbirds, at ~30mM, while glucose-transporting PM GLUT1 and PM GLUT3 in the flight muscle and liver, respectively, declined in fasted birds. Our results suggest that glucose uptake capacity is dynamically reduced in response to fasting, allowing for maintenance of elevated Blood glucose levels, while fructose uptake capacity remains constitutively elevated promoting depletion of Blood total fructose within the first hour of a fast.
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Glucose transporter expression in an avian nectarivore: the ruby-throated hummingbird (Archilochus colubris).
PloS one, 2013Co-Authors: Kenneth C. Welch, Amina Allalou, Prateek Sehgal, Jason X. Cheng, Aarthi AshokAbstract:Glucose transporter (GLUT) proteins play a key role in the transport of monosaccharides across cellular membranes, and thus, Blood Sugar Regulation and tissue metabolism. Patterns of GLUT expression, including the insulin-responsive GLUT4, have been well characterized in mammals. However, relatively little is known about patterns of GLUT expression in birds with existing data limited to the granivorous or herbivorous chicken, duck and sparrow. The smallest avian taxa, hummingbirds, exhibit some of the highest fasted and fed Blood glucose levels and display an unusual ability to switch rapidly and completely between endogenous fat and exogenous Sugar to fuel energetically expensive hovering flight. Despite this, nothing is known about the GLUT transporters that enable observed rapid rates of carbohydrate flux. We examined GLUT (GLUT1, 2, 3, & 4) expression in pectoralis, leg muscle, heart, liver, kidney, intestine and brain from both zebra finches (Taeniopygia guttata) and ruby-throated hummingbirds (Archilochus colubris). mRNA expression of all four transporters was probed using reverse-transcription PCR (RT-PCR). In addition, GLUT1 and 4 protein expression were assayed by western blot and immunostaining. Patterns of RNA and protein expression of GLUT1-3 in both species agree closely with published reports from other birds and mammals. As in other birds, and unlike in mammals, we did not detect GLUT4. A lack of GLUT4 correlates with hyperglycemia and an uncoupling of exercise intensity and relative oxidation of carbohydrates in hummingbirds. The function of GLUTs present in hummingbird muscle tissue (e.g. GLUT1 and 3) remain undescribed. Thus, further work is necessary to determine if high capillary density, and thus surface area across which cellular-mediated transport of Sugars into active tissues (e.g. muscle) occurs, rather than taxon-specific differences in GLUT density or kinetics, can account for observed rapid rates of Sugar flux into these tissues.
Henning Morawietz - One of the best experts on this subject based on the ideXlab platform.
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Reprint of: Blood Sugar Regulation for Cardiovascular Health Promotion and Disease Prevention: JACC Health Promotion Series.
Journal of the American College of Cardiology, 2018Co-Authors: Peter E H Schwarz, Patrick Timpel, Lorenz Harst, Colin J Greaves, Mohammed K. Ali, Mary Beth Weber, Mohamad M. Almedawar, Jeffrey Lambert, Henning MorawietzAbstract:The primary objective of this study was to analyze the most up-to-date evidence regarding whether and how Blood Sugar Regulation influences cardiovascular health promotion and disease prevention by carrying out an umbrella review. Three separate, systematic literature searches identified 2,343 papers in total. Overall, 44 studies were included for data extraction and analysis. The included systematic reviews and meta-analyses published between January 1, 2016, and December 31, 2017, were of good to very good quality (median Overview Quality Assessment Questionnaire score = 17). Identified evidence suggests that cardiovascular disease (CVD) prevention services should consider Regulation of Blood glucose as a key target for intervention. Furthermore, the recommendations for effective intervention and service development/training described here for prevention of CVD should be adopted into evidence-based practice guidelines. Multidisciplinary teams should be formed to deliver multicomponent interventions in community-based settings. There may be substantial opportunities for integrating CVD and diabetes prevention services.
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Blood Sugar Regulation for Cardiovascular Health Promotion and Disease Prevention
Journal of the American College of Cardiology, 2018Co-Authors: Peter Schwarz, Patrick Timpel, Lorenz Harst, Colin J Greaves, Mohammed K. Ali, Jeffrey D Lambert, Mary Beth Weber, Mohamad M. Almedawar, Henning MorawietzAbstract:AbstractThe primary objective of this study was to analyze the most up-to-date evidence regarding whether and how Blood Sugar Regulation influences cardiovascular health promotion and disease preve...
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Blood Sugar Regulation for cardiovascular health promotion and disease prevention jacc health promotion series
Journal of the American College of Cardiology, 2018Co-Authors: Peter E H Schwarz, Patrick Timpel, Lorenz Harst, Colin J Greaves, Mohammed K. Ali, Jeffrey D Lambert, Mary Beth Weber, Mohamad M. Almedawar, Henning MorawietzAbstract:AbstractThe primary objective of this study was to analyze the most up-to-date evidence regarding whether and how Blood Sugar Regulation influences cardiovascular health promotion and disease preve...
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Reprint of: Blood Sugar Regulation for Cardiovascular Health Promotion and Disease Prevention
Journal of the American College of Cardiology, 2018Co-Authors: Peter Schwarz, Patrick Timpel, Lorenz Harst, Colin J Greaves, Mohammed K. Ali, Jeffrey D Lambert, Mary Beth Weber, Mohamad M. Almedawar, Henning MorawietzAbstract:AbstractThe primary objective of this study was to analyze the most up-to-date evidence regarding whether and how Blood Sugar Regulation influences cardiovascular health promotion and disease preve...
Colleen Fogarty Draper - One of the best experts on this subject based on the ideXlab platform.
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a 48 hour vegan diet challenge in healthy women and men induces a branch chain amino acid related health associated metabolic signature
Molecular Nutrition & Food Research, 2018Co-Authors: Irene Vassallo, Cristiana Milone, Ornella Comminetti, Irina Monnard, Jean Philippe Godin, Max Scherer, Andrea Cara, Colleen Fogarty Draper, Mingming SuAbstract:cope : Research is limited on diet challenges to improve health. A short-term, vegan protein diet regimen nutritionally balanced in macronutrient composition compared to an omnivorous diet was hypothesized to improve metabolic measurements of Blood Sugar Regulation, Blood lipids, and amino acid metabolism. Methods and results : This randomized, cross-over, controlled vegan verses animal diet challenge was conducted on 21 (11 female,10 male) healthy participants. Fasting plasma was measured during a 3-day diet intervention for clinical biochemistry and metabonomics. Intervention diet plans met individual caloric needs. Meals were provided and supervised. Diet compliance was monitored. Conclusions : The vegan diet lowered triglycerides, insulin and homeostatic model assessment (HOMA-IR), bile acids, elevated magnesium levels, and changed branched-chain amino acids (BCAAs) metabolism (p<0.05), potentiating insulin and Blood Sugar control after 48 hours. Cholesterol control improved significantly in the vegan verses omnivorous diets. Plasma amino acid and magnesium concentrations positively correlated with dietary amino acids. Polyunsaturated fatty acids and dietary fiber inversely correlated with insulin, HOMA-IR and triglycerides. Nutritional biochemistries, BCAAs, insulin and HOMA-IR were impacted by sexual dimorphism. A health-promoting, BCAA-associated metabolic signature was produced from a short-term, healthy, controlled, vegan diet challenge when compared with a healthy, controlled, omnivorous diet. This article is protected by copyright. All rights reserved
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A 48‐Hour Vegan Diet Challenge in Healthy Women and Men Induces a BRANCH‐Chain Amino Acid Related, Health Associated, Metabolic Signature
Molecular Nutrition & Food Research, 2017Co-Authors: Colleen Fogarty Draper, Irene Vassallo, Cristiana Milone, Ornella Comminetti, Irina Monnard, Jean Philippe Godin, Max Scherer, Andrea Cara, Mingming Su, Wei JiaAbstract:cope : Research is limited on diet challenges to improve health. A short-term, vegan protein diet regimen nutritionally balanced in macronutrient composition compared to an omnivorous diet was hypothesized to improve metabolic measurements of Blood Sugar Regulation, Blood lipids, and amino acid metabolism. Methods and results : This randomized, cross-over, controlled vegan verses animal diet challenge was conducted on 21 (11 female,10 male) healthy participants. Fasting plasma was measured during a 3-day diet intervention for clinical biochemistry and metabonomics. Intervention diet plans met individual caloric needs. Meals were provided and supervised. Diet compliance was monitored. Conclusions : The vegan diet lowered triglycerides, insulin and homeostatic model assessment (HOMA-IR), bile acids, elevated magnesium levels, and changed branched-chain amino acids (BCAAs) metabolism (p
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A 48-Hour Vegan Diet Challenge in Healthy Women and Men Induces a BRANCH-Chain Amino Acid Related, Health Associated, Metabolic Signature.
Molecular nutrition & food research, 2017Co-Authors: Colleen Fogarty Draper, Irene Vassallo, Cristiana Milone, Ornella Comminetti, Irina Monnard, Jean Philippe Godin, Max Scherer, Alessandro Di Cara, Wei JiaAbstract:cope : Research is limited on diet challenges to improve health. A short-term, vegan protein diet regimen nutritionally balanced in macronutrient composition compared to an omnivorous diet was hypothesized to improve metabolic measurements of Blood Sugar Regulation, Blood lipids, and amino acid metabolism. Methods and results : This randomized, cross-over, controlled vegan verses animal diet challenge was conducted on 21 (11 female,10 male) healthy participants. Fasting plasma was measured during a 3-day diet intervention for clinical biochemistry and metabonomics. Intervention diet plans met individual caloric needs. Meals were provided and supervised. Diet compliance was monitored. Conclusions : The vegan diet lowered triglycerides, insulin and homeostatic model assessment (HOMA-IR), bile acids, elevated magnesium levels, and changed branched-chain amino acids (BCAAs) metabolism (p
Aarthi Ashok - One of the best experts on this subject based on the ideXlab platform.
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Glucose transporter expression in an avian nectarivore: the ruby-throated hummingbird (Archilochus colubris).
PloS one, 2013Co-Authors: Kenneth C. Welch, Amina Allalou, Prateek Sehgal, Jason X. Cheng, Aarthi AshokAbstract:Glucose transporter (GLUT) proteins play a key role in the transport of monosaccharides across cellular membranes, and thus, Blood Sugar Regulation and tissue metabolism. Patterns of GLUT expression, including the insulin-responsive GLUT4, have been well characterized in mammals. However, relatively little is known about patterns of GLUT expression in birds with existing data limited to the granivorous or herbivorous chicken, duck and sparrow. The smallest avian taxa, hummingbirds, exhibit some of the highest fasted and fed Blood glucose levels and display an unusual ability to switch rapidly and completely between endogenous fat and exogenous Sugar to fuel energetically expensive hovering flight. Despite this, nothing is known about the GLUT transporters that enable observed rapid rates of carbohydrate flux. We examined GLUT (GLUT1, 2, 3, & 4) expression in pectoralis, leg muscle, heart, liver, kidney, intestine and brain from both zebra finches (Taeniopygia guttata) and ruby-throated hummingbirds (Archilochus colubris). mRNA expression of all four transporters was probed using reverse-transcription PCR (RT-PCR). In addition, GLUT1 and 4 protein expression were assayed by western blot and immunostaining. Patterns of RNA and protein expression of GLUT1-3 in both species agree closely with published reports from other birds and mammals. As in other birds, and unlike in mammals, we did not detect GLUT4. A lack of GLUT4 correlates with hyperglycemia and an uncoupling of exercise intensity and relative oxidation of carbohydrates in hummingbirds. The function of GLUTs present in hummingbird muscle tissue (e.g. GLUT1 and 3) remain undescribed. Thus, further work is necessary to determine if high capillary density, and thus surface area across which cellular-mediated transport of Sugars into active tissues (e.g. muscle) occurs, rather than taxon-specific differences in GLUT density or kinetics, can account for observed rapid rates of Sugar flux into these tissues.
Raafay Syed Ali - One of the best experts on this subject based on the ideXlab platform.
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Glucose transporter expression and Regulation following a fast in the ruby-throated hummingbird, Archilochus colubris.
The Journal of Experimental Biology, 2020Co-Authors: Raafay Syed Ali, Morag F. Dick, Saad Muhammad, Dylan Sarver, Lily Hou, G. William Wong, Kenneth C. WelchAbstract:ABSTRACT Hummingbirds, subsisting almost exclusively on nectar Sugar, face extreme challenges to Blood Sugar Regulation. The capacity for transmembrane Sugar transport is mediated by the activity of facilitative glucose transporters (GLUTs) and their localisation to the plasma membrane (PM). In this study, we determined the relative protein abundance of GLUT1, GLUT2, GLUT3 and GLUT5 via immunoblot using custom-designed antibodies in whole-tissue homogenates and PM fractions of flight muscle, heart and liver of ruby-throated hummingbirds (Archilochus colubris). The GLUTs examined were detected in nearly all tissues tested. Hepatic GLUT1 was minimally present in whole-tissue homogenates and absent win PM fractions. GLUT5 was expressed in flight muscles at levels comparable to those of the liver, consistent with the hypothesised uniquely high fructose uptake and oxidation capacity of hummingbird flight muscles. To assess GLUT Regulation, we fed ruby-throated hummingbirds 1 mol l−1 sucrose ad libitum for 24 h followed by either 1 h of fasting or continued feeding until sampling. We measured relative GLUT abundance and concentration of circulating Sugars. Blood fructose concentration in fasted hummingbirds declined (∼5 mmol l−1 to ∼0.18 mmol l−1), while fructose-transporting GLUT2 and GLUT5 abundance did not change in PM fractions. Blood glucose concentrations remained elevated in fed and fasted hummingbirds (∼30 mmol l−1), while glucose-transporting GLUT1 and GLUT3 in flight muscle and liver PM fractions, respectively, declined in fasted birds. Our results suggest that glucose uptake capacity is dynamically reduced in response to fasting, allowing for maintenance of elevated Blood glucose levels, while fructose uptake capacity remains constitutively elevated promoting depletion of Blood total fructose within the first hour of a fast.
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Glucose transporter expression and Regulation following a fast in the ruby-throated hummingbird, Archilochus colubris.
2020Co-Authors: Raafay Syed Ali, Morag F. Dick, Saad Muhammad, Dylan Sarver, G. William Wong, Kenneth C. WelchAbstract:Hummingbirds subsist almost exclusively on nectar Sugar and face extreme challenges Blood Sugar Regulation. Transmembrane Sugar transport is mediated by facilitative glucose transporters (GLUTs) and the capacity for Sugar transport is dependent on both the activity of GLUTs and their localisation to the plasma membrane (PM). In this study, we determined the relative protein abundance in whole-tissue (WT) homogenates and PM fractions via immunoblot using custom antibodies for GLUT1, GLUT2, GLUT3, and GLUT5 in flight muscle, heart, and, liver of ruby-throated hummingbirds (Archilochus colubris). GLUTs examined were detected in nearly all tissues tested. Hepatic GLUT1 was minimally present in WT homogenates and absent in PM fractions. GLUT5 was expressed in hummingbird flight muscles at levels comparable to that of their liver, consistent with the hypothesised uniquely high fructose-uptake and oxidation capacity of this tissue. To assess GLUT Regulation, we fed ruby-throated hummingbirds 1M sucrose ad libitum for 24 hours followed by either 1 hour of fasting or continued ad libitum feeding until sampling. We measured relative GLUT abundance and concentrations of circulating Sugars. Blood fructose concentration in fasted hummingbirds declined from ~5mM to ~0.18mM, while fructose-transporting PM GLUT2 and PM GLUT5 did not change in abundance. Blood glucose concentrations remained elevated in both fed and fasted hummingbirds, at ~30mM, while glucose-transporting PM GLUT1 and PM GLUT3 in the flight muscle and liver, respectively, declined in fasted birds. Our results suggest that glucose uptake capacity is dynamically reduced in response to fasting, allowing for maintenance of elevated Blood glucose levels, while fructose uptake capacity remains constitutively elevated promoting depletion of Blood total fructose within the first hour of a fast.