2015 ICDM, 15-17, Jejudob Island, Korea Recent Advances in Diabetic Microvascular Complications. DPP-4 Inhibition and Diabetic Nephropathy

Size: px

Start display at page:

Download "2015 ICDM, 15-17, Jejudob Island, Korea Recent Advances in Diabetic Microvascular Complications. DPP-4 Inhibition and Diabetic Nephropathy"

Darlene Garrison
5 years ago
Views:

1 2015 ICDM, 15-17, Jejudob Island, Korea Recent Advances in Diabetic Microvascular Complications DPP-4 Inhibition and Diabetic Nephropathy Daisuke Koya Department of Diabetology & Endocrinology Kanazawa Medical University

2 Kidney fibrosis in diabetes How can we combat kidney fibrosis in diabetes?

3 DPP-4 levels are elevated in diabetic kidney DPP-4 on endothelial cells Kanasaki et al Diabetes 2014

4 Endothelial-to-Mesenchymal transition (EndMT) EndMT is appeared to be an important orign of myofibroblast or activated fibroblast. Kanasaki K, et al. Frontiers in Endocrinology 2013;4:7 Srivastava SP, et al. Biomed Res Int. 2013

5 Dipeptidyl Peptidase-4 (DPP-4) DPP-4 is a cell surface aminopeptidase which was originally characterized as a T-cell differentiation antigen (CD26). It is distributed throughout the body and cleaves numerous substrates other than incretin hormones. High expression of DPP-4 is associated with fibrogenic potential of fibroblasts. In diabetic mice, DPP-4 overexpression in endothelial cell is associated with EndMT and kidney fibrosis. Fleischer B.. Immunol Today 1994 Drucker, D. J. Exp. Opin. Investig. Drugs 2003 Rinkevich, Science, 2015 Keizo kanasaki. Diabetes, 2014

6 Inhibition of DPP-4 by linagliptin in diabetic kidney is associated with the amelioration of kidney fibrosis. Control DM DM+linagliptin Urine albumin

7 Linagliptin-suppressed kidney fibrosis in diabetic CD-1 mice was associated with EndMT inhibition Control DM DM+linagliptin Kanasaki et al Diabetes 2014

8 Fibrogenic cross-talk in diabetic kidney Summary of Kanasaki Diabetes 2014 Increased DPP-4 activity Diabetes High TGF-b activity microrna29 suppression DPP-4 inhibition

9 Linagliptin inhibited TGF-b2-induced smad3 phosphorylation in HMVEC How?

10 What is the relevance of DPP-4 on TGF-b/smad signal transduction?

11 Integrin β1 Integrins are cell surface receptors that play key roles in cell migration and adhesion. β1-integrin is the most critical one that can pair with different α- subunits, it is reported that it has a fibrotic potential, and high β1-integrin level is associated with seriously kidney fibrosis. Chen, et al. JCI 2014 Hynes, R. O. Cell 2002 Hind et al. Frontiers in Bioscience 2009

12 *The loss of DPP-4 surface expression has shown to be associated with decreased phosphorylation of integrin β1 at the S785 residue, which has a key role in cellular adhesion to ECM. *CD26 potentiates mesothelioma tumor cell invasion through its interaction with αvβ1 integrin. Tsutomu Sato, et al. Proc Amer Assoc Cancer Res, 2005 Toshihiro Okamoto, et al, PLoS One Hypothesis: DPP-4-integrin β1 interaction is a therapeutic target for kidney fibrosis in diabetes via the normalization of endothelial cell homeostasis and inhibition of EndMT.

13 Aim: To identify the interaction of integrin β1 and DPP-4 in diabetic kidney and EndMT Specific Aim 1: Intervention with DPP-4 inhibitor, linagliptin on STZ-induced diabetes-associated with suppression of integrin β1 and EndMT. Specific Aim 2: To analyze the interaction between DPP-4 and integrin β1. Specific Aim 3: To identify the mechanism of DPP- 4 /integrin β1 interaction on endothelial homeostasis

14 DPP-4/integrin β1/ DAPI P-integrin β1/dpp4 /DAPI P-integrin β1/cd31 /DAPI Specific Aim 1: The association of DPP-4 and integrin β1 expression in kidney of STZ- induced diabetic CD1 mice Control DM DM+linagliptin Control DM DM+linagliptin Control DM DM+linagliptin

15 Short summary 1 The protein expression levels of integrin β1, phosphorylated-integrin β1, and DPP- 4 were all increased in endothelial cells in STZ-induced diabetic kidneys; all of these inductions were suppressed by linagliptin treatment.

16 Specific Aim 2: To analyze the interaction between DPP-4 and integrin β1 TGF-β2 Control sirna TGF-β2 Control sirna Integrin β1 sirna DPP-4 sirna DPP-4 110kDa CD31 130kDa Integrin β1 P-integrin β1 GAPDH VWF αsma SM22α GAPDH αsma 88kDa DPP-4 88kDa Integrin β1 37kDa P-integrin β1 250kDa GAPDH 42kDa 23kDa 37kDa 42kDa 110kDa 88kDa 88kDa 37kDa Integrin β1 or DPP-4 deletion in endothelial cell is associated with inhibition of EndMT in cultured endothelial cells

17 Duolink (DPP-4-integrin β1)/dapi Duolink (TGF-βR1-TGF-βR2)/DAPI Interaction between DPP-4 and integrin β1 regulates TGF-β receptors heterodimer formation Control Control Control sirna +TGF-β2 TGF-β2 Integrin β1 sirna Integrin β1 sirna +TGF-β2 TGF-β2 +linagliptin DPP-4 sirna DPP-4 sirna +TGF-β2 Rik Derynck, nature TGF-β activation is dependent on the TGF-βR1/2 heterodimer formation We also perform the immunoprecipitation for DPP-4 and integrin β1 interaction and get the same result.

18 Integrin β1 activation antibody induced EndMT and DPP-4 expression ;also induce the interaction of DPP-4 and integrin β1 and TGFβ receptors heterodimer formation Control IgG Integrin β1 activation antibody CD31 αsma 130kDa 42kDa SM22α 23kDa β-actin 42kDa DPP-4 P-integrin β1 Integrin β1 110kDa 88kDa 88kDa β-actin 42kDa

19 Short summary 2 1. Deletion of integrin β1 was associated with suppression of DPP-4. By contrast, the activation of integrin β1 by a specific antibody induced EndMT associated with DPP-4 induction. 2. The interaction of DPP-4 and integrin β1 is associated with the induction of EndMT and TGFβ signaling by enhancing the TGF-βRs heterodimer formation.

20 Specific Aim 3: To identify the mechanism of DPP-4 /integrin β1 interaction on endothelial homeostasis Diverse VEGF receptors and their role on EndMT Integrin b1 EndMT VEGF-R1/ Flt-1 VEGF-R2/ KDR/Flk-1 sflt-1 PlGF VEGF-A VEGF-R3/ Flt-4 VEGF-B VEGF-C Neuropilin-1 Neuropilin-2 VEGF-D

21 VEGF-R2/CD31/ DAPI VEGF-R1/CD31/ DAPI DPP-4 regulate VEGFRs expression in vivo and in vitro In vivo In vitro Control DNA A. Control DPP-4 DNA VEGF DPP-4 110kDa VEGF-R1 180kDa Control DM DM+linagliptin VEGF-R2 180kDa D. P-ERK 75kDa β-actin 42kDa DM Control DM DM+linagliptin

22 Short summary 3 The DPP-4 is key factor to inhibit VEGFinduced survival signaling in endothelial cells.

23 DPP-4-integrin β1 interaction and EndMT ECM TGFβ2 activate α β1 α β1 DPP4 DPP4 T G F β R 1 T G F β R 2 VEGFR2 VEGFR1 VEGFR1 VEGFR2 TGF-βRs heterodimer formation EndMT and fibrosis

24 Conclusion The interaction between DPP-4 and integrin β1 is a therapeutic target for diabetic microvessel complications including diabetic nephropathy.

## : Co-correspondence. Address correspondence to:

## : Co-correspondence. Address correspondence to: Page 1 of 40 Linagliptin-mediated DPP-4 inhibition ameliorates kidney fibrosis in streptozotocin-induced diabetic mice by inhibiting endothelial-to-mesenchymal transition in a therapeutic regimen Keizo