BIOL1XX8 2024 Glucose Homeostasis PDF

18/01/2024 Feedback loops and the regulation of glucose homeostasis Presented by Professor Peter Thorn, Charles Perkins Centre Thornlab.com OLE Health Challenges: Diabetes OLEO1503 or OLET1504 WARNING This presentation may contain material that has been reproduced and communicated to you by or on be...

18/01/2024 Feedback loops and the regulation of glucose homeostasis Presented by Professor Peter Thorn, Charles Perkins Centre Thornlab.com OLE Health Challenges: Diabetes OLEO1503 or OLET1504 WARNING This presentation may contain material that has been reproduced and communicated to you by or on behalf of the University of Sydney in accordance with section 113P of the Copyright Act 1968 (Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Do not remove this notice The University of Sydney Page 1 1 Principles of feedback loops The University of Sydney Page 2 2 1 18/01/2024 For example, temperature control: The University of Sydney Page 3 3 Aims Describe the mechanisms that maintain blood sugar in the fed state Describe the mechanisms that maintain blood sugar during fasting The University of Sydney Page 4 4 2 18/01/2024 Importance of circulating glucose Glucose is the main source of energy for the brain Glycogen stores in the brain are low Use of other fuels, like free fatty acids, is poor, although ketones can be used The University of Sydney Page 5 5 How does glucose enter the body? Ragil The University of Sydney Page 6 6 3 18/01/2024 Glucose will diffuse along a gradient The University of Sydney Page 7 7 Diffusion across tissues will, alone dampen changes in blood glucose levels The University of Sydney Page 8 8 4 18/01/2024 How does glucose enter the body? Ragil The University of Sydney Page 9 9 But glucose cannot cross membranes: needs glucose transporters The University of Sydney Page 10 10 5 18/01/2024 The University of Sydney Page 11 11 GLUT transporters GLUT4 GLUT2 GLUT4 The University of Sydney Page 12 12 6 18/01/2024 Glucose diffusion does not provide enough control End section 1 The University of Sydney Page 13 13 Regulation needs both mechanisms for both storage and release section 2 The University of Sydney Page 14 14 7 18/01/2024 STORAGE RELEASE The University of Sydney Page 15 The University of Sydney Page 16 15 16 8 18/01/2024 The University of Sydney Page 17 The University of Sydney Page 18 17 18 9 18/01/2024 Amino acids lactate ketones Free fatty acids glycerol End section 2 The University of Sydney Page 19 19 Mid-lecture activity 100 mg/dl = 5.5 mM section 3 The University of Sydney Page 20 20 10 18/01/2024 Control of glucose storage and release The University of Sydney Page 21 21 INSULIN Amino acids lactate Glucagon ketones Free fatty acids glycerol The University of Sydney Page 22 22 11 18/01/2024 INSULIN GLUCAGON The University of Sydney Page 23 The University of Sydney Page 24 23 24 12 18/01/2024 The University of Sydney Page 25 The University of Sydney Page 26 25 26 13 18/01/2024 INSULIN Targets: Muscle to promote glucose uptake Liver to promote glycogen storage Fat to promote glucose uptake Amino acids lactate Glucagon Targets: Liver to promote glycogen breakdown ketones and glucose release Free fatty acids glycerol The University of Sydney Page 27 27 Aims Describe the mechanisms that maintain blood sugar in the fed state Describe the mechanisms that maintain blood sugar during fasting The University of Sydney Page 28 28 14