Valvular Interstitial Valvular Interstitial Cell Calcification Cell Calcification

Liwen GuJuly 5, 2005

Prof C. Simmons

Background

Endothelial Cells

Interstitial Cells

http://www.ctsnet.org/edmunds/Chapter28section2.html (Fig 28-4)

20 000 deaths caused by valvular diseases in 2002 (US)

Aortic sclerosis: thickening of the valve leaftlets calcification

Calcification process

The American Journal of Cardiology Vol.94; 2004

Objectives

• How calcification occurs in valvular interstitial cells (VIC)

• Effects of endothelial cell (EC) paracrine factors on interstitial cells - signaling processShort-term/immediate goal:

induce calcification in VIC culture

1st Experiment

Purpose: to induce calcification in VIC culture by providing

an osteogenic supplemented (OS) media

Method: -Porcine Aortic Valvular Interstitial Cells (PAVIC) – 14 days-added 10 mmol/L βGP to VIC media

Hypothesis:-more nodule formation compared to control-alkaline phosphatase activity-mineralization

Ann Thorac Surg 2003; 75:457-66

1st Experiment (cont’d)

Results:

+OS control (-OS)Explanations:

- βGP is not enough-ALP protocol-no positive control

2nd Experiment

Method: -3 time points: 0, 14, 21 days-10 mmol/L βGP + 50μg/mL ascorbic acid + 50ng RANKL (J.J. Kaden et al. Journal of Molecular and Cellular Cardiology 36(2004)57-66)

Future Experiments

VIC alone VIC + EC

1. VIC + osteogenic supplement (βGP)

2. VIC + OS (βGP + ascorbic acid)

3. Gene expression

4. VIC + EC conditioned media

5. VIC-EC co-culture

6. VIC collagen gel + EC

Future Experiments

VIC alone VIC + EC

1. VIC + osteogenic supplement (βGP)

2. VIC + OS (βGP + ascorbic acid)

3. Gene expression

4. VIC + EC conditioned media

5. VIC-EC co-culture

6. VIC collagen gel + EC

Future Experiments

VIC alone VIC + EC

1. VIC + osteogenic supplement (βGP)

2. VIC + OS (βGP + ascorbic acid)

3. Gene expression

4. VIC + EC conditioned media

5. VIC-EC co-culture

6. VIC collagen gel + EC

Co-Culture

Shin et al. “Endothelial Cells Modulate Osteogenesis in Calcifying Vascular Cells”. J Vasc Res 2004;41: 193-201

Method:

Results:

Future Experiments

VIC alone VIC + EC

1. VIC + osteogenic supplement (βGP)

2. VIC + OS (βGP + ascorbic acid)

3. Gene expression

4. VIC + EC conditioned media

5. VIC-EC co-culture

6. VIC collagen gel + EC

Acknowledgements

• Prof C. Simmons

• Simmons Group:Alice HoYifei WangSamir RazaJan ChenJoel Rebello

• Davies lab

Thank You!

Contact: liwen.gu@utoronto.ca