[Thalidomide and unilateral limb defects: the Italian chapter of a neverending story]. / Talidomide e difetti monolaterali degli arti: il capitolo italiano di una storia infinita.

Fifty years after the event, Italy introduced legislation to compensate malformations in children - now in their sixties - born to mothers who had been prescribed the antiemetic drug thalidomide for morning sickness. However, compensation has been denied to people 'only' damaged in one half of their body as opposed to those with bilateral malformations. The present study reviews the papers describing case series of children born with 'thalidomide embryopathy' in the UK, Germany, and other countries around 1960. Most clinical series were not organized on the basis of inclusion/exclusion criteria, thus allowing for probable selection and information biases on maternal use of thalidomide. In any case, they included a sizable number of children with a unilateral limb defect born from mothers certainly exposed to thalidomide during the relevant pregnancy. In many of these children, limb defects were associated with visceral malformations, as frequently observed following exposure to thalidomide in utero. Similarly, later literature reviews were not bias-free in their choice of articles, as is the case of a recently proposed 'diagnostic algorithm' for thalidomide-caused specific malformations and of the advice by the Italian National Institute of Health ruling out the possibility of thalidomide producing unilateral limb defects. Overall, the scientific evidence suggests that thalidomide can cause unilateral limb defects.

Fetal proximal and distal limb anomalies following exposure to mycophenolate mofetil during pregnancy: A case report and review of the literature.

BACKGROUND: Mycophenolate mofetil (MMF) is currently used in a wide spectrum of autoimmune diseases and has been rendered very effective in the management of systemic lupus erythematosus and lupus nephritis. MMF is known to be teratogenic (FDA category D) and therefore, women in childbearing period receiving MMF should be counselled to use effective contraceptive methods to avoid an unplanned pregnancy. CASE: A 22-year-old lady accidentally discovered to be pregnant while using MMF as a treatment of lupus nephritis which was replaced later on by azathioprine. After maternal and fetal evaluation, maternal lupus flare was confirmed and multiple fetal skeletal deformities associated with intrauterine growth restriction (IUGR) were diagnosed by 4-dimensional ultrasound. Termination of pregnancy was decided after shared decision making. CONCLUSION: Women in childbearing period should be advised to postpone pregnancy for at least six weeks after stoppage of MMF therapy because of its potential teratogenic effects during pregnancy.

In ovo hyperglycemia causes congenital limb defects in chicken embryos via disruption of cell proliferation and apoptosis.

While the correlation between diabetes during pregnancy and birth defects is well-established, how hyperglycemia causes developmental abnormalities remains unclear. In this study, we developed a novel "hyperglycemic" chicken embryonic model by administrating various doses of glucose to fertilized eggs at embryonic stages HH16 or HH24. When the embryos were collected at HH35, the LD50 was 1.57 g/Kg under HH16 treatment and 0.93 g/Kg under HH24 treatment, indicating that "hyperglycemic" environments can be lethal for the embryos. When exposed to a dose equal to or higher than 1 g/Kg glucose at HH16 or HH24, more than 40% of the surviving chicken embryos displayed heart defects and/or limb defects. The limb defects were associated with proliferation defects of both the wing and leg buds indicated by reduced numbers of p-H3S10 labeled cells. These limb defects were also associated with ectopic apoptosis in the leg bud and expression changes of key apoptotic genes. Furthermore, glucose treatment induced decreased expression of genes involved in Shh-signaling, chondrogenesis, and digit patterning in the limb bud. In summary, our data demonstrated that a high-glucose environment induces congenital heart and limb defects associated with disrupted cell proliferation and apoptosis, possibly through depressed Shh-signaling.

Thalidomide Inhibits Human iPSC Mesendoderm Differentiation by Modulating CRBN-dependent Degradation of SALL4.

Exposure to thalidomide during a critical window of development results in limb defects in humans and non-human primates while mice and rats are refractory to these effects. Thalidomide-induced teratogenicity is dependent on its binding to cereblon (CRBN), the substrate receptor of the Cul4A-DDB1-CRBN-RBX1 E3 ubiquitin ligase complex. Thalidomide binding to CRBN elicits subsequent ubiquitination and proteasomal degradation of CRBN neosubstrates including SALL4, a transcription factor of which polymorphisms phenocopy thalidomide-induced limb defects in humans. Herein, thalidomide-induced degradation of SALL4 was examined in human induced pluripotent stem cells (hiPSCs) that were differentiated either to lateral plate mesoderm (LPM)-like cells, the developmental ontology of the limb bud, or definitive endoderm. Thalidomide and its immunomodulatory drug (IMiD) analogs, lenalidomide, and pomalidomide, dose-dependently inhibited hiPSC mesendoderm differentiation. Thalidomide- and IMiD-induced SALL4 degradation can be abrogated by CRBN V388I mutation or SALL4 G416A mutation in hiPSCs. Genetically modified hiPSCs expressing CRBN E377V/V388I mutant or SALL4 G416A mutant were insensitive to the inhibitory effects of thalidomide, lenalidomide, and pomalidomide on LPM differentiation while retaining sensitivity to another known limb teratogen, all-trans retinoic acid (atRA). Finally, disruption of LPM differentiation by atRA or thalidomide perturbed subsequent chondrogenic differentiation in vitro. The data here show that thalidomide, lenalidomide, and pomalidomide affect stem cell mesendoderm differentiation through CRBN-mediated degradation of SALL4 and highlight the utility of the LPM differentiation model for studying the teratogenicity of new CRBN modulating agents.

Abnormal Development of Hyalomma Marginatum Ticks (Acari: Ixodidae) Induced by Plant Cytotoxic Substances.

The increasing application of toxic plant substances to deter and fight ticks proves the need for investigations focused on the elucidation of their impact on the developmental stages and populations of these arthropods. We examined the course of embryogenesis and egg hatch in Hyalomma marginatum ticks under the effect of cytotoxic plant substances. The investigations demonstrated that the length of embryonic development of egg batches treated with 20 µL of a 0.1875% colchicine solution did not differ significantly from that in the control group. Colchicine caused the high mortality of eggs (16.3%) and embryos (9.7%), disturbances in larval hatch (8.1%), and lower numbers of normal larval hatches (65.6%). In 0.2% of the larvae, colchicine induced anomalies in the idiosoma (67.6%) and gnathosoma (22.5%) as well as composite anomalies (8.5%). The study demonstrates that cytotoxic compounds with an effect similar to that of colchicine can reduce tick populations and cause teratological changes, which were observed in the specimens found during field studies. Since there are no data on the toxic effects of active plant substances on other organisms and the risk of development of tick resistance, a strategy for the use of such compounds in tick control and the management of plant products should be developed.

Defining a critical period in calvarial development for Hedgehog pathway antagonist-induced frontal bone dysplasia in mice.

The Hedgehog (Hh) signalling pathway is essential for cellular proliferation and differentiation during embryonic development. Gain and loss of function of Hh signalling are known to result in an array of craniofacial malformations. To determine the critical period for Hh pathway antagonist-induced frontal bone hypoplasia, we examined patterns of dysmorphology caused by Hh signalling inhibition. Pregnant mice received a single oral administration of Hh signalling inhibitor GDC-0449 at 100 mg•kg-1 or 150 mg•kg-1 body weight at preselected time points between embryonic days (E)8.5 and 12.5. The optimal teratogenic concentration of GDC-0449 was determined to be 150 mg•kg-1. Exposure between E9.5 and E10.5 induced frontal bone dysplasia, micrognathia and limb defects, with administration at E10.5 producing the most pronounced effects. This model showed decreased ossification of the frontal bone with downregulation of Hh signalling. The osteoid thickness of the frontal bone was significantly reduced. The amount of neural crest-derived frontal bone primordium was reduced after GDC-0449 exposure owing to a decreased rate of cell proliferation and increased cell death.

The teratogenic effects of thalidomide on limbs.

Thalidomide remains notorious as a result of the damage it caused to children born to mothers who used it to treat morning sickness between 1957 and 1961. The re-emergence of the drug to treat a range of conditions including erythema nodosum leprosum (a complication of leprosy) has led to a new generation of thalidomide damaged children being born in Brazil. Although thalidomide affects most of the developing tissues and organs of the body, the damage to the limbs is striking. Indeed phocomelia, the severe reduction or loss of the proximal long bones with retention of the distal hand/foot plate remains the stereotypical image of thalidomide. This review focuses on the type and range of damage thalidomide caused to the limbs, reviews current understanding of the mechanisms underlying thalidomide-induced limb malformations and outlines some of the challenges remaining in elucidating its teratogenicity.

A clinical review and introduction of the diagnostic algorithm for thalidomide embryopathy (DATE).

Thalidomide embryopathy results from the ingestion of thalidomide in the first trimester during pregnancy, causing multiple forms of congenital abnormalities of variable severity that involve all systems. The skeletal findings most frequently affect the limbs, particularly the upper limbs and hands. Increasingly, several genetic disorders with similar birth defects have been identified. New cases of malformations owing to possible exposure to thalidomide continue to present through both historical and current usage. However, inadequate proof of ingestion, marked phenotypic variation and the possibility of an alternative genetic condition, hinder the diagnosis of thalidomide embryopathy. We introduce a 'diagnostic algorithm for thalidomide embryopathy' (DATE) diagnostic software that can potentially provide a numerical score for the likelihood of birth defects in an individual as being caused by exposure to thalidomide and to provide a differential diagnosis based on the pattern of malformation.

Thalidomide and neurotrophism.

BACKGROUND: Following the thalidomide disaster (1958-62), Henkel and Willert analysed the pattern of dysmelia in the long bones (J Bone Joint Surg Br. 51:399-414, 1969) and the extremities, Willert and Henkel (Z Orthop Ihre Grenzgeb. 107:663-75, 1970). Willert's material from deformed extremities is re-examined here asking "How does thalidomide reduce the skeleton?" MATERIALS AND METHODS: We reviewed the original data collection of Willert and Henkel (Z Orthop Ihre Grenzgeb. 107:663-75, 1970), comprising musculoskeletal histology slides from 30 children affected by thalidomide with radiographs of hands (19 cases) and feet (4 cases). RESULTS: All original observations by Willert and Henkel (Z Orthop Ihre Grenzgeb. 107:663-75, 1970), were verified. Radial rays of the hand disappeared early, but the foot was spared until late. Radiology confirms that bone reduction in the hand (aplasia or hypoplasia in the thumb and index finger) coincides with sensory segmental nerve C6. In the foot, reduction of the toes is rare, but mesenchymal excess (polydactyly) occurs in the hallux (L5 sclerotome), usually associated with absent tibia (L4 sclerotome). Histology confirms skeletal mesenchymal components to be unremarkable, contrasting with grossly abnormal bony architecture, a striking discordance between microscopic and macroscopic findings. No necrosis or vascular pathology was seen. CONCLUSION: The basic lesion was an abnormal quantity rather than quality of mesenchyme. Cell populations result from cellular proliferation, controlled in early limb bud formation by neurotrophism. Thalidomide is a known sensory neurotoxin in adults. In the embryo, sensorineural injury alters neurotrophism, causing increased or diminished cell proliferation in undifferentiated mesenchyme. Differentiation into normal cartilage occurs later, but within an altered mesenchymal mass. Reduction or excess deformity results, with normal histology, a significant finding. The primary pathological condition is not in the skeleton, but in the nerves.

[Hedgehog pathway antagonist-induced oromandibular limb hypogenesis in mouse].

Objective: To analysis teratogenic effect of GDC-0449 to fetus and set up the animal model of GDC-0449 induced oromandibular limb hypogenesis in mouse for further research of its pathogenesis. Methods: Twenty-seven pregnant Institute of Cancer Research (ICR) mice were randomly divided into: control group, embryonic day 8.5 (E8.5) exposed groups, E9.5 exposed groups, E10.5 exposed groups, E11.5 exposed groups, E12.5 exposed groups, E13.5 exposed groups, E14.5 exposed groups and E15.5 exposed groups. Each group had 3 mice. Exposed groups were treated with the Hedgehog pathway antagonist GDC-0449 at a single dose 150 mg/kg by oral gavage from E8.5 to E15.5. At E16.5, embryonic phenotypes were analyzed in detail by stereo microscope and histology. After establish an optimal dysmorphogenic concentration, 6 pregnant ICR mice were randomly divided into control group and the optimal group, embryonic phenotypes were analyzed by whole-mount skeletal staining and micro-computed tomography at E18.5. Results: The mice were exposed to GDC-0449 on E11.5 and E12.5 had a high incidence of cleft palate. GDC-0449 exposed between E9.5 and E10.5 caused craniofacial and limb dysmorphology, including micrognathia, microglossia, ectrodactylia, partial anodontia and cleft palate. Most interestingly, these are extremely similar to oromandibular limb hypogenesis syndrome. Conclusions: The results of this study indicate that GDC-0449 can be used to induce micrognathia, microglossia, ectrodactylia, partial anodontia and cleft palate. This work established a novel mouse model for oromandibular limb hypogenesis.

CPS49-induced neurotoxicity does not cause limb patterning anomalies in developing chicken embryos.

Thalidomide notoriously caused severe birth defects, particularly to the limbs, in those exposed in utero following maternal use of the drug to treat morning sickness. How the drug caused these birth defects remains unclear. Many theories have been proposed including actions on the forming blood vessels. However, thalidomide survivors also have altered nerve patterns and the drug is known for its neurotoxic actions in adults following prolonged use. We have previously shown that CPS49, an anti-angiogenic analog of thalidomide, causes a range of limb malformations in a time-sensitive manner in chicken embryos. Here we investigated whether CPS49 also is neurotoxic and whether effects on nerve development impact upon limb development. We found that CPS49 is neurotoxic, just like thalidomide, and can cause some neuronal loss late developing chicken limbs, but only when the limb is already innervated. However, CPS49 exposure does not cause defects in limb size when added to late developing chicken limbs. In contrast, in early limb buds which are not innervated, CPS49 exposure affects limb area significantly. To investigate in more detail the role of neurotoxicity and its impact on chicken limb development we inhibited nerve innervation at a range of developmental timepoints through using ß-bungarotoxin. We found that neuronal inhibition or ablation before, during or after limb outgrowth and innervation does not result in obvious limb cartilage patterning or number changes. We conclude that while CPS49 is neurotoxic, given the late innervation of the developing limb, and that neuronal inhibition/ablation throughout limb development does not cause similar limb patterning anomalies to those seen in thalidomide survivors, nerve defects are not the primary underlying cause of the severe limb patterning defects induced by CPS49/thalidomide.

Committee Opinion No. 717 Summary: Sulfonamides, Nitrofurantoin, and Risk of Birth Defects.

The evidence regarding an association between the nitrofuran and sulfonamide classes of antibiotics and birth defects is mixed. As with all patients, antibiotics should be prescribed for pregnant women only for appropriate indications and for the shortest effective duration. During the second and third trimesters, sulfonamides and nitrofurantoins may continue to be used as first-line agents for the treatment and prevention of urinary tract infections and other infections caused by susceptible organisms. Prescribing sulfonamides or nitrofurantoin in the first trimester is still considered appropriate when no other suitable alternative antibiotics are available. Pregnant women should not be denied appropriate treatment for infections because untreated infections can commonly lead to serious maternal and fetal complications.

Committee Opinion No. 717: Sulfonamides, Nitrofurantoin, and Risk of Birth Defects.

The evidence regarding an association between the nitrofuran and sulfonamide classes of antibiotics and birth defects is mixed. As with all patients, antibiotics should be prescribed for pregnant women only for appropriate indications and for the shortest effective duration. During the second and third trimesters, sulfonamides and nitrofurantoins may continue to be used as first-line agents for the treatment and prevention of urinary tract infections and other infections caused by susceptible organisms. Prescribing sulfonamides or nitrofurantoin in the first trimester is still considered appropriate when no other suitable alternative antibiotics are available. Pregnant women should not be denied appropriate treatment for infections because untreated infections can commonly lead to serious maternal and fetal complications.

Possible association between acetazolamide administration during pregnancy and multiple congenital malformations.

Congenital malformations might occur because of environmental or genetic factors, and sometimes occur because of unknown causes. Acetazolamide is a carbonic anhydrase inhibitor that is used to treat idiopathic intracranial hypertension, glaucoma, and epilepsy. The use of acetazolamide has not been recommended for pregnant women because of reported teratogenic risks. Congenital malformations, such as ectrodactyly, syndactyly, cleft lip/palate, and retarded incisor teeth development, have been reported in experimental animals. However, tooth agenesis due to the use of acetazolamide has not been reported yet. Oligodontia is a severe type of tooth agenesis involving six or more congenitally missing teeth. The causes of oligodontia are attributed to environmental factors, such as irradiation, drugs, trauma, tumors, infection, genetic factors, or a combination. There is no credible evidence of undesirable effects of acetazolamide use in human pregnancy. However, we report a case of a 12-year-old Saudi boy who was exposed to maternal acetazolamide (1,000 mg/day) for treatment of idiopathic intracranial hypertension before pregnancy, during the first trimester, and throughout the pregnancy. This treatment might have resulted in some congenital malformations, such as ectrodactyly, syndactyly, and oligodontia.

Does folinic acid ameliorates retinoic acid induced teratogenicity in chick embryo?

OBJECTIVE: To investigate the protective effect of folinic acid on the hatching ability and developmental defects in a retinoic acid-induced teratogenic model of chick embryo. METHODS: The experimental study was conducted at the Department of Anatomy, Regional Centre of the College of Physicians and Surgeons Pakistan, Islamabad, from February 2009 to February 2010. Chicken eggs were divided into two experimental groups and a control group. The first experimental group was injected with retinoic acid to induce a defective model, while the second experimental group was concomitantly injected folinic acid to observe its protective effects on retinoic acid-induced defects in the development and hatching process. Both groups were compared with the age-matched control group. RESULTS: A total of 90 fertilised eggs were divided into three groups. The experimental groups had significantly more delayed and assisted hatchings compared to the control group (p<0.05) but the difference between the experimental groups regarding the mode and day of hatching was insignificant (p>0.05). CONCLUSIONS: Irrespective of the presence of folinic acid, prenatal retinoic acid exposure significantly altered the hatchability characteristics in the experimental groups compared to the control.

Novel FANCI mutations in Fanconi anemia with VACTERL association.

Fanconi anemia (FA) is an inherited bone marrow failure syndrome caused by mutations in DNA repair genes; some of these patients may have features of the VACTERL association. Autosomal recessive mutations in FANCI are a rare cause of FA. We identified FANCI mutations by next generation sequencing in three patients in our FA cohort among several whose mutated gene was unknown. Four of the six mutations are novel and all mutations are likely deleterious to protein function. There are now 16 reported cases of FA due to FANCI of whom 7 have at least 3 features of the VACTERL association (44%). This suggests that the VACTERL association in patients with FA may be seen in patients with FANCI mutations more often than previously recognized.

Pathogenesis of Pregabalin-Induced Limb Defects in Mouse Embryos.

PURPOSE: It is known that antiepileptic drugs might adversely affect neuronal function and thus influence brain development. However, we have reported that limb deformities are one of the most prominent disturbances caused by pregabalin (PGB) in the developing embryo. The aim of this work is to gain a better understanding of possible molecular mechanisms behind the musculoskeletal injuries and limb deformities associated with PGB. METHODS: Pregnant mice divided into four groups. Each mouse received an intraperitoneal injection (IP) of 0, 20 (group I), 40 (group II) or 80 (group III) mg/kg/day of PGB during the organogenesis period. On gestational day 18, embryos were separated and their limbs were dissected. Levels of apoptotic proteins were analyzed by Western blotting. To establish whether apoptosis is present in the limbs, the specimens were examined by TUNEL. Pathological findings were also reported as a score ranging from 1 to 3 based on the level of differentiation. RESULTS: Western blot analysis demonstrated that PGB in all PGB-treated groups significantly upregulated the levels of cleaved caspase-3, 8 and 9. Also, the results showed that PGB exposure increased the percentage of TUNEL positive cells in different limb tissues especially the mesenchymal tissue. The histopathological findings revealed that PGB administration to pregnant mice inhibited limb tissue differentiation, albeit to varying degrees. CONCLUSIONS: The result of our study revealed that apoptosis and inhibition of limb tissue differentiation play an important role in the pathogenesis of PGB-induced limb malformations. Both intrinsic and extrinsic caspase-dependent pathways of cell death are important in mediating the abnormal limb development triggered by insult with the PGB. Evaluating the effect of PGB on molecules involved in the cross-talk between intrinsic and extrinsic apoptotic pathways and cell adhesion, migration, proliferation, and differentiation during embryonic development can further help to identify and clarify the involved mechanisms.

Thalidomide embryopathy: Follow-up of cases born between 1959 and 2010.

BACKGROUND: Thalidomide is a known teratogen and it is estimated that more than ten thousand babies were affected by thalidomide embryopathy (TE), which is characterized mainly by limb defects, but can involve many organs and systems. Most people with TE were only evaluated at birth and it is not well established if thalidomide exposure during embryonic development leads to later effects. We analyzed the clinical history of adults with TE to better understand this gap in the clinical findings of TE. METHODS: Brazilian individuals with TE were invited to answer a clinical questionnaire which considered family history, social information, medical history, and current clinical and psychological health status. A clinical examination was also performed, including on the infant subjects to evaluate congenital anomalies. The characterization of the features was analyzed using descriptive statistics and Chi-square or Fisher's exact test. RESULTS: The congenital anomalies caused by thalidomide were reviewed in 28 Brazilian individuals, and the questionnaire was applied to the 23 adult subjects with TE (aged 19 to 55). Progressive deafness and dental loss were reported. From the comparison of TE individuals with the general Brazilian population, the early onset of cardiovascular diseases (p = 0.009) and a higher frequency of psychological disorders (p = 0.011) were observed. CONCLUSION: Although there is no sufficient evidence that thalidomide exposure caused or worsened the described events, this approach helps to better understand the TE phenotype, improves the clinical diagnosis, and can lead to adequate health support for these individuals.

MicroRNA-34a is dispensable for p53 function as teratogenesis inducer.

The tumor suppressor protein p53 is a powerful regulator of the embryo's susceptibility to diverse teratogenic stimuli, functioning both as a teratogenesis inducer and suppressor. However, the targets that p53 engages to fulfill its functions remain largely undefined. We asked whether the microRNA (miRNA) miR-34 family, identified as one of the main targets of p53, mediates its function as a teratogenesis inducer. For this, pregnant ICR-, p53- and miR-34a-deficient mice, as well as rats, were exposed to 5-aza-2'-deoxycytidine (5-aza), a teratogen inducing limb reduction anomalies (LRA) of the hindlimbs in mice and either the hindlimbs or forelimbs in rats. Using hind- and forelimb buds of 5-aza-exposed embryos, we identified that the miR-34 family members are the most upregulated miRNAs in mouse and rat limb buds, with their increase level being significantly higher in limb buds destined for LRA. We showed that p53 mediates the 5-aza-induced miR-34 transcription followed by met proto-oncogene and growth-arrest-specific 1 target suppression in embryonic limb buds. We demonstrated that p53 regulates the teratogenic response to 5-aza acting as a teratogenesis inducer albeit miR-34a deletion does not affect the susceptibility of mice to 5-aza. Overall, our study thoroughly characterizes the expression and regulation of miR-34 family in teratogen-resistant and teratogen-sensitive embryonic structures and discusses the involvement of epigenetic miRNA-mediated pathway(s) in induced teratogenesis.

Teratogenicity of asbestos in mice.

Possible teratogenicity of 3 different asbestos (crocidolite, chrysotile and amosite) was assessed in CD1(ICR) mice. Dams on day 9 of gestation were given a single intraperitoneal administration at dose of 40 mg/kg body weight of asbestos suspended in 2% sodium carboxymethyl cellulose solution in phosphate buffered saline, while dams in the control group were given vehicle (10 ml/kg body weight). Dams and fetuses were examined on day 18 of gestation. To compare with the control group, the mean percentage of live fetuses in implantations in the group given crocidolite and the incidence of dams with early dead fetuses in the groups given chrysotile or amosite were increased. While no external or skeletal malformation was observed in the control group, the incidence of external malformation (mainly reduction deformity of limb) in the group given amosite, and the incidences of skeletal malformation (mainly fusion of vertebrae) in the all dosed groups were significantly increased. The result indicated that asbestos (crocidolite, chrysotile and amosite) have fetotoxicity and teratogenicity in mice.