Inflammation of islets and apoptosis. And how to protect the β-cell from Death. Kathrin Maedler, Larry L. Hillblom Islet Research Center, UCLA

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1 Inflammation of islets and apoptosis And how to protect the β-cell from Death Kathrin Maedler, Larry L. Hillblom Islet Research Center, UCLA

2 T1DM control Apoptosis in T1DM 1.4 Insulin Caspase T1DM control Meier et al, Diabetologia 2005 beta cell area (% total pancreatic area) T1DM control % beta cells positive for cleaved Caspase 3

3 Apoptosis in T2DM control T2DM Butler et al, Diabetes 2003

4 Apoptosis in transplanted islets Extrinsic Signals: Fas Cytokines GLP-1 A? B human islet intraportal porcine islet Diabetes 48, Oct allograft J.Leuc.Biol 77, May 2005 Environment in the liver Hypoxia c-flip Intrinsic Signals: Hypoxia Reactive oxygen Species Nutrient Withdrawal DNA damage XIAP TLR-4 up-regulation Clin.Exp.Imm144, Feb Activation of intrahepatic endothelial and Kupffer cells, resulting in inflammation and thrombosis. TLR-4 Diabetes 55, July 2006 insulin FASEB J. 21, May 2007 Apoptosis in mouse islet transplanted, inhibited by anticoagulant APC, Diabetes 53, Nov.2004

5 The Mechanisms of β-cell apoptosis in T1DM Islet antigen Mathis et al, Nature 2002

6 The Mechanisms of β-cell apoptosis in T2DM β-cells

7 The Mechanisms of β-cell apoptosis in T2DM β-cells

8 The Mechanisms of β-cell apoptosis in T2DM β-cell mass β-cells β-cell dysfunction β-cell apoptosis insulin resistance GLUCOSE Free fatty acids free radicals/ oxidative stress IAPP ER stress inos pro-inflammatory Cytokine anti-inflammatory cytokines Adipokines diabetic genes: PPARγ, Fas/FasL Calpain 10, HNF4 TCF7L2, Znt-8, CDKAL-1

9 Glucose is an important fuel for the β-cell Glucose β-cells insulin secretion Glucose Regulation Proliferation

10 Glucose-induced β-cell turnover Glucose β-cells Apoptosis Impaired function Diabetes

11 Glucose-induced β-cell turnover Glucose ZB4 FasL Caspase activation Fas β-cells Apoptosis Diabetes Impaired function Proliferation +Flip Are there other regulator of the Fas pathway in the β-cell?

12 The effect of IL-1β on the β-cell IL-1β IL-1R1 IL-1AcP Fas, Caspases, inos, SOCS-3, bcl-2... PDX-1, Isl-1, GLUT2... JNK/p38/ERK IκB NFκB Apoptosis impaired function PKCδ β-cell

13 Regulation of IL-1β & IL-1Ra in the β-cell in vivo nondiabetic control IL-1β Insulin Merge patient with T2DM nondiabetic control IL-1Ra Insulin Merge patient with T2DM Maedler et al, PNAS 2004

14 Glucose-induced β-cell turnover Glucose IL-1β ZB4 IL-1Ra FasL Caspase activation Fas β-cells Apoptosis Diabetes Impaired function Inhibit β-cell apoptosis by blocking IL-1β signaling?

15 The effect of IL-1β/ IL-1Ra on the β-cell IL-1R1 IL-1β IL-1AcP IL-1Ra Fas, Caspases, inos, SOCS-3, bcl-2... PDX-1, Isl-1, GLUT2... JNK/p38/ERK IκB NFκB Apoptosis impaired function PKCδ β-cell

16 IL-1Ra is protective against β-cell apoptosis and improves β-cell function glucose 5.5 mm 33.3 mm 33.3 mm+il-1ra 1.0 insulin secretion (pmol/islet) TUNEL Insulin basal stimulated glucose (mm) IL1-Ra % Ki67pos β-cells IL-1Ra (ng/ml) β-cell proliferation after 4 days of culture p<0.05 to 5.5 mm p<0.05 to 33.3 mm

17 Is IL-1Ra protective against diabetes progression in vivo? Glucose IL-1Ra Apoptosis Impaired function Does IL-1Ra influence β-cell function? β-cell survival? β-cell gene transcription?

18 Is IL-1Ra protective against diabetes progression in vivo? Start with five weeks old male C57BL/6 Daily injections of IL-1Ra or solvent for 12 weeks solvent IL-1Ra control diet HFD: high fat/ high sucrose diet control diet HFD: high fat/ high sucrose diet

19 IL-1Ra improves glucose tolerance Intraperitoneal glucose tolerance test after 12 weeks of diet and treatment control control + IL-1Ra Blood glucose (mm) time after injection (min) p<0.05 to untreated same diet +p<0.05 to control diet

20 IL-1Ra improves glucose tolerance Intraperitoneal glucose tolerance test after 12 weeks of diet and treatment control control + IL-1Ra High fat diet 25 Blood glucose (mm) time after injection (min) p<0.05 to untreated same diet +p<0.05 to control diet

21 IL-1Ra improves glucose tolerance Intraperitoneal glucose tolerance test after 12 weeks of diet and treatment control control + IL-1Ra High fat diet High fat diet + IL-1Ra 25 Blood glucose (mm) time after injection (min) p<0.05 to untreated same diet +p<0.05 to control diet

22 IL-1Ra improves insulin secretion Intraperitoneal glucose tolerance test after 12 weeks of treatment min 30 min 1.5 Insulin secretion µg/l IL-1Ra - + control p<0.05 to basal same treatment

23 IL-1Ra improves insulin secretion Intraperitoneal glucose tolerance test after 12 weeks of treatment min 30 min 1.5 Insulin secretion µg/l IL-1Ra control High fat diet p<0.05 to basal same treatment

24 IL-1Ra improves insulin secretion Intraperitoneal glucose tolerance test after 12 weeks of treatment min 30 min 1.5 Insulin secretion µg/l IL-1Ra control High fat diet p<0.05 to basal same treatment

25 IL-1Ra improves β-cell turnover control High fat diet Ki67-positive β-cells % of control IL-1Ra control diet High fat diet untreated IL-1Ra Ki67 Insulin DAPI p<0.05 to untreated same diet

26 β-cell apoptosis no increase in β-cell apoptosis in HFD-mice in pancreas sections BUT: higher sensitivity in isolated islets TUNEL-positive β-cells % of control IL-1Ra untreated IL-1Ra control High fat diet control diet High fat diet p<0.05 to control same treatment +p<0.05 to control HFD

27 HFD reduces insulin mrna which is restored by IL-1Ra treatment Quantitative RT-PCR analysis Insulin 300 Insulin/GAPDH % control IL-1Ra control High fat diet p<0.05 HFD to control same treatment

28 Summary & Conclusion IL-1Ra protects from diet-induced diabetes. IL-1Ra improves β-cell function. IL-1Ra improves β-cell survival. IL-1Ra overexpression increases beta cell replication and mass in transplanted islets, and improves metabolic outcome. (Diabetologia Mar;50(3):602-11). Results from a recent clinical study in patients with T2DM showed that IL-1Ra improved glycaemic control and β-cell function (NEnglJMed 356: ). The fact that IL-1Ra improves β-cell function is in favor for the critical role of IL-1β signaling in the β-cell in type 1, type 2 diabetes and in islet transplantation. Our data implements IL-1Ra for a potential therapy of diabetes.

29 Acknowledgements Andres Quiros Valerie Zamudio Nadine Sauter Ruth Schruefer Fabienne Schulthess Michelle Peng Luan Shu Lendy Lee Michael Muehle Heather Gerber Leena Haataja, Anil Bhushan & Peter Butler, LHIRC, UCLA Jake Lusis, Dept. of Genetics, UCLA Jose Oberholzer, University of Illinois at Chicago Marc Donath, USZ Zurich American Diabetes Association Larry L. Hillblom Research Foundation NIH Swiss National Foundation German Research Foundation ICR for human islets