Satyanarayana R. Pondugula, DVM, PhD

The laboratory has interests in understanding the role of nuclear receptors (NRs), including pregnane xenobiotic receptor (PXR), in health and disease. It has been shown that PXR plays a central role in activating the expression of drug metabolizing enzymes. Changes in the expression of PXR-regulated drug metabolizing enzymes may lead to adverse drug interactions. The more recent evidence also suggests that PXR has implications in cancer pathogenesis, chemotherapeutic drug resistance, and endocrine disruption. However, the cellular mechanisms that regulate PXR activity are poorly understood. We will investigate the mechanisms regulating PXR activity by using modern molecular and cell biology approaches.

Pondugula SR, Xie W, Chen T. PXR and hepatocyte proliferation. J Exp Clin Med 2010;2(6):260-261.

Pondugula SR, Tong A, Wu J, Cui J, Chen T. Protein phosphatase 2Cbl regulates human pregnane X receptor-mediated CYP3A4 gene expression in HepG2 liver carcinoma  cells. Drug Metab Dispos. 2010 Sep;38(9):1411-6.

Pondugula SR, Raveendran NN, Marcus DC. Regulators of Ion Transport by Semicircular Canal Duct Epithelium: P2Y Receptors, protein kinase C and phosphatidylinositol 3-kinase. BMC Research Notes. 2010 Apr 14;3(1):100.

Pondugula SR, Dong H, Chen T. Phosphorylations and protein-protein interactions in PXR-mediated CYP3A Repression. Expert Opin Drug Metab Toxicol. 2009 Aug;5(8):861-73. 

Pondugula SR, Brimer-Cline C, Wu J, Schuetz EG, Tyagi RK, Chen T. A phosphomimetic mutation at threonine-57 abolishes transactivation activity and alters nuclear localization pattern of human pregnane X receptor. Drug Metab Dispos. 2009 Apr;37(4):719-30. 

Kim SH, Kim KX, Raveendran NN, Wu T, Pondugula SR, Marcus DC. Regulation of Epithelial Sodium Channel (ENaC)-Mediated Sodium Transport by Glucocorticoids in Reissner's Membrane Epithelium. Am J Physiol Cell Physiol. 2009 Mar;296(3):C544-57. 

Pondugula SR, Raveendran NN, Ergonul Z, Deng Y, Chen J, Sanneman JD, Palmer LG, Marcus DC. Glucocorticoid-regulation of genes in the amiloride-sensitive sodium transport pathway by semicircular canal duct epithelium of neonatal rat.  Physiol. Genomics. 2006 Jan 12;24(2):114-23. 

Yamauchi D, Raveendran NN, Pondugula SR, Kampalli SB, Sanneman JD, Harbidge DG, Marcus DC.  Vitamin D upregulates expression of ECaC1 mRNA in semicircular canal. Biochem Biophys Res Commun.  2005 Jun 17;331(4):1353-7.

Pondugula SR, Sanneman JD, Wangemann P, Milhaud PG, Marcus DC.  Glucocorticoids stimulate cation absorption by semicircular canal duct epithelium via epithelial sodium channel.  Am J Physiol Renal Physiol. 2004 Jun; 286(6):F1127-35.

Milhaud PG, Pondugula SR, Lee JH, Herzog M, Lehouelleur J, Wangemann P, Sans A, Marcus DC. Chloride secretion by semicircular canal duct epithelium is stimulated via β₂-adrenergic receptors. Am J Physiol Cell Physiol. 2002 Dec; 283(6):C1752-60.