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CAPTION: ©Lilly USA, LLC 2021. All rights reserved.
TITLE: GIP and GLP-1 in Physiology & Tpe 2 Diabetes
[Title moves to the corner. Dr. Frias speaks to the camera. His name and credentials write on-screen.]
CAPTION: Dr. Juan Pablo Frias, Medical Director, National Research Institute, Los Angeles, California
DR. FRIAS: Hello. I’m Dr. Juan Pablo Frias, medical director at National Research Institute in Los Angeles. In this video, we’ll discuss the potential pleiotropic effects of endogenous GIP and GLP-1 as they relate to type 2 diabetes.
CAPTION: The purpose of this video is to educate on the roles of GIP and GLP-1 in physiology and type 2 diabetes. To understand these mechanisms, physiological GIP and/or GLP-1 must be increased or blocked. Data for these concepts arise from studies in humans, rodents, and in vitro systems.
DR. FRIAS: The purpose of this material is to educate health care providers on the roles of the incretin hormones glucose-dependent insulinotropic polypeptide, or GIP, and glucagon-like peptide-1, or GLP-1, in physiology and type 2 diabetes. In order to understand these mechanisms, physiology must undergo manipulations to increase levels of incretins or to block the actions of GIP, GLP-1, or both. Data for these concepts arise from several experimental methods: in humans, rodents, and in vitro systems.
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TITLE: The incretin effect
[Cut to Dr. Frias standing, speaking to the camera. On-screen graphic highlights relevant organs/tissue.]
DR. FRIAS: In this section, we’ll describe the effect of GIP and GLP-1 in healthy people and the loss of the incretin effect in people with type 2 diabetes.
[Cut to Dr. Frias with chart in corner: "The incretin effect in healthy individuals". Dr. Frias glances at it as he continues to talk to us.]
DR. FRIAS: When comparing insulin secretion following an oral glucose load to insulin secretion following intravenous glucose infusion, the dynamic difference between the two insulin secretory responses is known as the incretin effect.
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DR. FRIAS (VOICEOVER): This shows that healthy individuals have a stronger insulin response to oral glucose than intravenous glucose infusion, demonstrating the role that incretin hormones play in insulin secretion in response to oral glucose intake.
[Cut to Dr. Frias with chart in corner: "The incretin effect is impaired in people with type 2 diabetes". Dr. Frias occasionally glances at it as he continues to talk to us.]
DR. FRIAS: In people with type 2 diabetes, the incretin effect is reduced. On the left, we can see the normal incretin effect in healthy individuals, ...
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DR. FRIAS (VOICEOVER): ... but in people with type 2 diabetes shown on the right, the difference in insulin secretion between an oral glucose dose and intravenous glucose infusion is diminished, indicating an impaired incretin effect. The reduced incretin effect contributes to postprandial hyperglycemia in patients with type 2 diabetes.
[Cut to Dr. Frias full-screen, wide shot. Mechanism of Action appears in corner of the screen. We see incretins binding to receptors on pancreatic cells. Dr. Frias glances at it as he continues to talk to us.]
DR. FRIAS: GIP and GLP-1 are gut-derived hormones that regulate the incretin effect. GIP and GLP-1 signal to pancreatic islets to enhance glucose-dependent insulin secretion.
[Cut to Dr. Frias full-screen, close-up, with chart in corner: GIP and GLP-1 enhance glucose-dependent insulin secretion in healthy individuals"]
DR. FRIAS: Clinical data from healthy individuals demonstrate that infusion of physiologic levels of GIP and/or GLP-1 enhances glucose-dependent insulin secretion.
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CAPTION: Relative contribution of GIP and GLP-1 to glucose clearance
DR. FRIAS (VOICEOVER): GIP and GLP-1 are responsible for the majority of postprandial glucose clearance, but endogenous GIP generates more of an effect on insulin-mediated glucose clearance compared with endogenous GLP-1.
[Cut to Dr. Frias with chart in corner: "Measuring the relative contributions of GIP and GLP-1 to glucose clearance in healthy individuals". Dr. Frias glances at it as he continues to talk to us.]
DR. FRIAS: In the study shown here, the relative contributions of GIP and GLP-1 to insulin-mediated glucose clearance were measured. Healthy individuals were given placebo or receptor antagonists to block the individual effects of endogenous GIP and GLP-1. This demonstrates that GIP and GLP-1 are both required for postprandial insulin-mediated glucose clearance.
[Cut to Dr. Frias with summary text in corner.]
CAPTION: Endogenous GIP and GLP-1 regulate insulin-mediated glucose clearance.1 Endogenous GIP and GLP-1 differ in their relative contribution to the incretin effect in healthy humans.
DR. FRIAS: In summary, GIP and GLP-1 are incretin hormones that regulate insulin-mediated glucose clearance and differ in their relative contributions to the incretin effect in healthy humans.
CAPTION: The incretin effect is impaired in people with type 2 diabetes.
DR. FRIAS: However, the endogenous incretin effect is impaired in people with type 2 diabetes, which contributes to an inability to properly regulate postprandial glucose.