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

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.

An improved multicellular human organoid model for the study of chemical effects on palatal fusion

“…TPM is a known CP teratogen. TPM also upregulates TGFβ1 and downstream Sox9 in mouse and human palate mesenchyme, which regulates palatogenesis in the mouse and human, and an increase or decrease in Sox9 can lead to disrupted palatal fusion (Rafi et al, 2021). While TPM may affect palate fusion in vivo, by this mechanism, the likelihood of a Sox9 mechanism is low in our organoid model as Sox9 regulates neural crest cells and our model does not contain neural crest cells.…”

“…Chemicals were suspended in DMSO at a stock concentration of 10, 20, or 100 mM, stored as stock solutions in −20°C and serial diluted in CC medium +1% P/S/A (abx) on the day of dosing to provide a 1% DMSO concentration at final test chemical dosing concentrations. Concentrations of test chemicals were selected based on previous studies in our laboratory (Belair et al, 2018) and in the literature (Kim et al, 2015; Kitase & Shuler, 2013; Rafi et al, 2021). Organoids stained with CellTracker™ dye were placed by organoid type in wells of a 96‐well plate in groups of 5–7 per well in 100 μL CC medium + abx and 100 μL 2% DMSO vehicle control or experimental chemicals at 2× final concentration were added to the well to dilute to final concentration.…”

“…CP can be induced in mice and humans by environmental factors including smoking (Chung et al, 2000) or diabetes (Spilson et al, 2001) and an imbalance of endogenous chemicals, such as epidermal growth factor (EGF) or retinoic acid (RA; Abbott & Pratt, 1988; Roa Fuentes et al, 2022; Wilson et al, 1953). CP can also be induced by exposure to teratogenic consumer chemicals, such as anti‐epileptic drugs valproic acid (VPA) and topiramate (TPM), and drugs such as anti‐neoplastic agent nocodazole (Guveli et al, 2017; Jentink et al, 2010; Kitase & Shuler, 2013; Margulis et al, 2012; Martinelli et al, 2020; Paulson & Paulson, 1981; Rafi et al, 2021).…”

Phentermine and Topiramate: Monotherapy and Their Combination Efficacy in the Treatment of Children and Adults with Obesity

“…Лечение топираматом взрослого населения с ожирением не вызывало каких-либо серьезных побочных явлений [27,35]. Применение препарата противопоказано при беременности, так как связано с повышенным риском врожденных дефектов развития ротоглотки, сердца и мочеполовой системы [36][37][38]. Кроме того, топирамат может снижать эстрогенный компонент оральных контрацептивов, поэтому женщинам репродуктивного возраста необходимо соблюдать меры предосторожности.…”

A Narrative Review: Phentermine and Topiramate for the Treatment of Pediatric Obesity

“…59 Topiramate is classified as Pregnancy Category D and use during pregnancy has been linked to a significantly increased risk of birth defects, affecting orofacial, cardiac and urogenital development. [67][68][69][70][71] In addition, topiramate can reduce the estrogen component of oral contraceptive medications, thus precautions must be provided for females of reproductive age. 42…”