Anti-epileptic drug topiramate upregulates TGFβ1 and SOX9 expression in primary embryonic palatal mesenchyme cells: Implications for teratogenicity.

Syed K Rafi,Jeremy P Goering,Nathan R Wilson,Lauren A Hipp,Adam J Olm-Shipman,Nicholas J Ernst,Sumedha Gunewardena,Everett G Hall,Irfan Saadi,James A Marrs

doi:10.1371/journal.pone.0246989

Syed K Rafi, Jeremy P Goering + Show 8 more

Open Access

https://doi.org/10.1371/journal.pone.0246989

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Journal: PloS one	Publication Date: Feb 12, 2021
Citations: 5	License type: CC BY 4.0

Affiliation: University of Kansas Medical Center

Abstract

Topiramate is an anti-epileptic drug that is commonly prescribed not just to prevent seizures but also migraine headaches, with over 8 million prescriptions dispensed annually. Topiramate use during pregnancy has been linked to significantly increased risk of babies born with orofacial clefts (OFCs). However, the exact molecular mechanism of topiramate teratogenicity is unknown. In this study, we first used an unbiased antibody array analysis to test the effect of topiramate on human embryonic palatal mesenchyme (HEPM) cells. This analysis identified 40 differentially expressed proteins, showing strong connectivity to known genes associated with orofacial clefts. However, among known OFC genes, only TGFβ1 was significantly upregulated in the antibody array analysis. Next, we validated that topiramate could increase expression of TGFβ1 and of downstream target phospho-SMAD2 in primary mouse embryonic palatal mesenchyme (MEPM) cells. Furthermore, we showed that topiramate treatment of primary MEPM cells increased expression of SOX9. SOX9 overexpression in chondrocytes is known to cause cleft palate in mouse. We propose that topiramate mediates upregulation of TGFβ1 signaling through activation of γ-aminobutyric acid (GABA) receptors in the palate. TGFβ1 and SOX9 play critical roles in orofacial morphogenesis, and their abnormal overexpression provides a plausible etiologic molecular mechanism for the teratogenic effects of topiramate.

Highlights

Our analysis indicated TGFβ1 as the central molecule affected by topiramate treatment of human embryonic palatal mesenchyme (HEPM) cells
We found that SRY-Box Transcription Factor 9 (SOX9) expression is increased following topiramate treatment (Fig 3A and 3B), which is consistent with a role for TGFβ1 in stabilizing SOX9 protein [38]
We utilized primary mouse embryonic palatal mesenchyme (MEPM) cells to validate TGFβ1 increase upon topiramate treatment

Summary

Introduction

Verispan’s Vector One: National (VONA) and IQVIA’s Total Patient Tracker (TPT) reported that, between January 2007 and December 2010, approximately 4.3 million patients filled 32.3 million topiramate prescriptions (FDA Drug Safety Communication, 03-04-2011) This number has risen to approximately 4.1 million patients receiving a prescription for topiramate between March 2014 and February 2016 (FDA Pediatric Post-marketing Pharmacovigilance and Drug Utilization Review for topiramate; June 20, 2016). In the North American Antiepileptic Drug Pregnancy Registry [15], the relative risk of oral clefts in topiramate-exposed pregnancies was ~13-fold higher than the general risk in births [16]. Topiramate treatment of primary MEPM cells increased expression of SRY-Box Transcription Factor 9 (SOX9), a TGFB1 target that causes cleft palate when abnormally expressed. We propose that perturbation of TGFβ pathway and SOX9 expression through γ-aminobutyric acid (GABA) receptors in the embryonic palate represents a plausible etiologic mechanism underlying topiramate-induced oral clefts

Materials and methods

Results

Discussion