Abstract: TH-PO702

Nicotine Enhances Renal Mesangial Cell Proliferation and Fibronectin Production in High Glucose Milieu via Activation of Wnt/β-Catenin Pathway

Session Information

Category: Diabetes

  • 501 Diabetes Mellitus and Obesity: Basic - Experimental

Authors

  • Lan, Xiqian, Feinstein Institute for Medical Research, Great Neck, New York, United States
  • Aslam, Rukhsana, Feinstein Institute for medical research, Glenoaks, New York, United States
  • Marashi Shoshtari, Seyedeh Shadafarin, The Feinstein Institute for Medical Research, Manhasset, New York, United States
  • Mishra, Abheepsa, Feinstein Institute of Medical Research, Northwell Health, MANHASSET, New York, United States
  • Malhotra, Ashwani, Feinstein Inst.Med research , Manhasset, New York, United States
  • Singhal, Pravin C., North Shore LIJ Health System, Great Neck, New York, United States
Background

Diabetic nephropathy (DN) is a major complication of diabetes mellitus, and the commonest cause of end-stage renal disease (ESRD) in developed countries, including USA. Clinical reports have demonstrated that cigarette smoking is an independent risk factor for chronic kidney disease including DN; however, the underlying molecular mechanisms are still not clear. Recent studies have demonstrated that nicotine, one of the highly active compounds in cigarette smoke, is required for cigarette smoking-accelerated chronic kidney disease. DN is characterized by mesangial expansion, a precursor of glomerulosclerosis. In this study, we examine the role of Wnt/β-catenin pathway in nicotine-mediated mesangial cell phenotype in high glucose milieu.

Methods

We treated human mesangial cells (HRMC) with both normal/high glucose (5 mM and 25 mM) and nicotine (0.1, 1, and 10 uM), and then examined their phenotype. To evaluatet proliferation, we counted the total cell numbers (in a hemocytometer), or calculated the Ki-67 positive cell ratio by using immunofluorescent staining. We also performed real-time PCR to detect the expression of Wnts, β -catenin, and fibronectin. In addition, we used β-catenin inhibitor FH535 to examine a causal relationship between nicotine and high glucose treatment-mediated mesangial cell proliferation and fibronectin production.

Results

In 5 mM glucose medium, nicotine increased the total cell count and Ki-67 positive cell ratio in a dose-dependent manner, indicating that nicotine enhanced mesangial cell proliferation in normal glucose milieu, only moderately; 25 mM glucose further exacerbated nicotine-mediated mesangial cell proliferation. Similarly, nicotine increased the expression of Wnts, β-catenin, and fibronectin in normal glucose milieu, however, high glucose further increased these expressions. Addition of FH535 significantly inhibited the cell proliferation and fibronectin production.

Conclusion

Nicotine enhansces renal mesangial cell proliferation and fibornectin production in high glucose milieu, and Wnt/ β-catenin pathway plays an important role to regulate these effects. The present study provides insight into molecular mechanisms involved in diabetic nephropathy.

Funding

  • NIDDK Support