Effects of thalidomide on Fgf8, Bmp4 and Hoxa11 expression in the limb bud in Kbl:JW rabbit embryos

Abstract

Thalidomide (TM) induces limb defects inhumans and some animal species including rabbits. Although the mechanism of TM-induced limb defects has been investigated for a long period, the limb development-related genes expressions have not been vigorously characterized in rabbits. In this study, we investigated the Fgf8, Bmp4 and Hoxa11 expressions in TM-treated JW rabbit embryos on gestation days (GDs) 10, 11 and 12 by whole mount in situ hybridization. On GDs 10 and 11, growth retardation of the embryo was induced by TM treatment. The Fgf8 expression lengths on GDs 10 and 11 in the forelimb bud were significantly or tended to be decreased in the TM-treated embryos, which was correlated to the growth retardation and was not considered to be directly relevant to the teratogenic effect of TM in the forelimb. The TM-induced characteristic changes in the expression pattern of Hoxa11 and Bmp4 on GDs 10 and/or 11 were not noted. On GD 12, TM-induced growth retardation was not noted and the Fgf8 and Bmp4 expressions were not changed. On the contrary, Hoxa11 expression was narrowed at the anterior region, which was located on the radial side, and was not changed at the middle and posterior regions in the forelimb bud and in all regions in the hindlimb bud. Because the radius malformations were induced by TM treatment, we concluded the decrease in the Hoxa11 expression was related to the TM-induced limb defects and can be a good marker for early prediction of the teratogenic effect of TM.

Augmentation of Pectoral Fin Teratogenicity by Thalidomide in Human Cytochrome P450 3A-Expressing Zebrafish

“…Fgf8 is believed to be indispensable for forelimb growth in chickens and rabbits, which are thalidomide-sensitive species [ 25 , 46 ]. Thalidomide reduced the expression of fgf8 and fgf10 in these species, suggesting that these are major targets of thalidomide in defects of forelimbs and wings [ 14 , 27 ]. In zebrafish, however, an fgf8 mutant (acerebellar, ace) had loss of the MHB but had normal pectoral fins, whereas the functional disruption of fgf24, fgf10 and fgf16 resulted in the loss of pectoral fins [ 46 , 47 ].…”

“…Thalidomide inhibited the expression of fibroblast growth factor 8 (fgf8) without having an effect on sonic hedgehog (shh) expression in pectoral fin buds of zebrafish [ 23 ]. Similarly, the expression of fgf8 and 10 was generally reduced by thalidomide exposure in wing buds of chickens and forelimb buds of rabbits [ 14 , 23 , 26 , 27 ]. Recently, Miyagawa and co-workers reported specific formation of an SALL4-CRBN complex and SALL4-specific degradation by 5-hydroxythalidomide, a major metabolite of thalidomide, but not by thalidomide, in humans and rabbits, while thalidomide induced the formation of an IKZF1–CRBN complex [ 28 ].…”

Genetic susceptibility to thalidomide embryopathy in humans: Study of candidate development genes

“…The seven genes here selected were chosen for their role in embryogenesis, especially limb development, and based on literature reports demonstrating their expression affected by thalidomide or its analogues. Assays with model organisms of thalidomide teratogenicity showed that genes important to limb development, such as Fgf8 , Fgf10 , Shh , and Bmp4 , are affected by thalidomide, having their expression altered after exposure to the drug (Hansen et al, ; Kawamura et al, ; Therapontos et al, ). The absence of p53, a protein involved in the repair of mutations emerged by the oxidative stress caused by thalidomide (Wells et al, ), was considered a contributing factor to the accumulation of DNA damage in limb cells of murine embryos, caused by 4‐hydroperoxycyclophosphamide, an analogue of cyclophosphamide (Moallem & Hales, ).…”

“…The p53 family (TP53, TP63 and TP73) is important during embryonic development and has already been associated to teratogenic outcomes (Rinne, Brunner, & van Bokhoven, 2007;Torchinsky & Toder, 2010). The Fibroblast growth factor-8 (FGF8), Fibroblast growth factor-10 (FGF10), Sonic hedgehog (SHH) and Bone morphogenetic protein 4 (BMP4) genes, important to limb development, were reported to had their expression changed in embryos of animal models exposed to thalidomide (Hansen, Gong, Philbert, & Harris, 2002;Kawamura, Yamashita, Yamauchi, Matsumoto, & Sato, 2014;Therapontos, Erskine, Gardner, Figg, & Vargesson, 2009).…”

Thalidomide interaction with inflammation in idiopathic pulmonary fibrosis

“…Further, Ito and Handa ( 2020 ) have explained the old and the current model of thalidomide mechanism of action to induce teratogenicity and its exploration in recent drug development (Ito and Handa 2020 ). Thalidomide downregulates fibroblast growth factor 8 (FGF8), thereby upregulating the apoptotic genes in the limbs (Kawamura et al 2014 ). Therefore, the FGF8 downregulation could be another molecular mechanism that explains the abnormally short limbs in deformed infants exposed to thalidomide during embryonic development (Asatsuma-Okumura et al 2019a ).…”