Thalidomide Analogs in Brazil: Concern About Teratogenesis

It has been more than 50 years since thalidomide was withdrawn from the world market due to its teratogenic potential. However, its widespread use around the world resumed due to its immunomo-dulatory and anti-angiogenic properties. The drug established itself in new therapies, and interest continued with the emergence of more potent analogs, the most notable being lenalidomide and pomalidomide, which are not approved in Brazil. The question that arises after analog synthesis is: Do these drugs also have the same teratogenic potential? The answer to this question is based only on experimental studies because exposure to humans is not authorized and has not yet been descri-bed. Although thalidomide has been recognized as a powerful human teratogen for many years, its molecular mechanisms of teratogenesis remain to be fully explained. Efforts with animal models and human genetic studies have clarified some important pathways that are most likely involved in the teratogenic action of thalidomide. However, it has not yet been possible to identify the teratogenic domain of the molecule from the therapeutic ones. Moreover, there are species-specific differences that must be taken into consideration when teratogenicity is evaluated.Título PT: Análogos da Talidomida no Brasil: Preocupação com a TeratogêneseFaz mais de 50 anos que a talidomida foi retirada do mercado mundial devido ao seu potencial teratogênico. Entretanto, seu uso disseminado em todo o mundo foi retomado devido às suas propriedades imunomodulatórias e antiangiogênicas. A droga foi utilizada em novas terapias e o interesse continuou com a emergência de análogos mais potentes, os mais notáveis deles sendo a lenalidomida e a pomalidomida, que não estão aprovados no Brasil. A questão que surge após a síntese dos análogos é: Estas drogas também têm o mesmo potencial teratogênico? A resposta a esta pergunta baseia-se apenas em estudos experimentais, pois a exposição a humanos não está autorizada e ainda não foi reporta-da. Embora a talidomida tenha sido durante muitos anos reconhecida como um poderoso teratógeno humano, os mecanismos moleculares da teratogênese ainda não foram com-pletamente explicados. Os esforços com modelos animais e estudos genéticos humanos para entender o efeito tóxico da droga esclareceram alguns importantes caminhos que estão muito provavelmente envolvidos na ação teratogênica. Entretanto, ainda não foi possível isolar o agente teratogênico das outras ações terapêuticas na talidomida e seus análogos. Além disso, há diferenças específicas da espécie que devem ser levadas em consideração quando a teratogenicidade é avaliada

Role of gut microbiota in infectious and inflammatory diseases

Thousands of microorganisms compose the human gut microbiota, fighting pathogens in infectious diseases and inhibiting or inducing inflammation in different immunological contexts. The gut microbiome is a dynamic and complex ecosystem that helps in the proliferation, growth, and differentiation of epithelial and immune cells to maintain intestinal homeostasis. Disorders that cause alteration of this microbiota lead to an imbalance in the host’s immune regulation. Growing evidence supports that the gut microbial community is associated with the development and progression of different infectious and inflammatory diseases. Therefore, understanding the interaction between intestinal microbiota and the modulation of the host’s immune system is fundamental to understanding the mechanisms involved in different pathologies, as well as for the search of new treatments. Here we review the main gut bacteria capable of impacting the immune response in different pathologies and we discuss the mechanisms by which this interaction between the immune system and the microbiota can alter disease outcomes

Comparative Genomics Identifies Putative Interspecies Mechanisms Underlying Crbn-Sall4-Linked Thalidomide Embryopathy

The identification of thalidomide–Cereblon-induced SALL4 degradation has brought new understanding for thalidomide embryopathy (TE) differences across species. Some questions, however, regarding species variability, still remain. The aim of this study was to detect sequence divergences between species, affected or not by TE, and to evaluate the regulated gene co-expression in a murine model. Here, we performed a comparative analysis of proteins experimentally established as affected by thalidomide exposure, evaluating 14 species. The comparative analysis, regarding synteny, neighborhood, and protein conservation, was performed in 42 selected genes. Differential co-expression analysis was performed, using a publicly available assay, GSE61306, which evaluated mouse embryonic stem cells (mESC) exposed to thalidomide. The comparative analyses evidenced 20 genes in the upstream neighborhood of NOS3, which are different between the species who develop, or not, the classic TE phenotype. Considering protein sequence alignments, RECQL4, SALL4, CDH5, KDR, and NOS2 proteins had the biggest number of variants reported in unaffected species. In co-expression analysis, Crbn was a gene identified as a driver of the co-expression of other genes implicated in genetic, non-teratogenic, limb reduction defects (LRD), such as Tbx5, Esco2, Recql4, and Sall4; Crbn and Sall4 were shown to have a moderate co-expression correlation, which is affected after thalidomide exposure. Hence, even though the classic TE phenotype is not identified in mice, a deregulatory Crbn-induced mechanism is suggested in this animal. Functional studies are necessary, especially evaluating the genes responsible for LRD syndromes and their interaction with thalidomide–Cereblon

Molecular mechanisms of Zika virus teratogenesis from animal studies : a systematic review protocol

Background: Due to the diversity of studies in animal models reporting that molecular mechanisms are involved in the teratogenic effect of the Zika virus (ZIKV), the objective of the present study is to evaluate the methodological quality of these studies, as well as to demonstrate which genes and which molecular pathways are affected by ZIKV in different animal models. Methods: This search will be performed in four databases: PubMed/MEDLINE, EMBASE, Web of Science, and Scopus, as well as in the grey literature. The studies selection process will be reported through the PRISMA Statement diagram model. All studies describing the molecular mechanisms possibly involved in the development of malformations caused by embryonic/fetal ZIKV exposure in animal models with an appropriate control group and methodology will be included (including, for instance, randomized and non-randomized studies). All animals used as experimental models for ZIKV teratogenesis may be included as long as exposure to the virus occurred during the embryonic/fetal period. From the selected studies, data will be extracted using a previously prepared standard form. Bias risk evaluation will be conducted following the SYRCLE’s Risk of Bias tool. All data obtained will be tabulated and organized by outcomes (morphological and molecular). Discussion: With the proposed systematic review, we expect to present results about the methodological quality of the published studies with animal models that investigated the molecular mechanisms involved in the teratogenic effect of ZIKV, as well as to show the studies with greater reliability

COVID-19 during pregnancy and adverse outcomes : concerns and recommendations from The Brazilian Teratology Information Service

SARS-CoV-2 virus was first identified in the beginning of 2020 and has spread all over the world, causing the Coronavirus Disease 2019 (COVID-19) pandemic. The virus is a member of the Coronavirus family, which includes viruses that cause common cold, Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). MERS and SARS are known by causing adverse events in pregnancy. Considering that SARS-CoV-2 is a new infection agent, little is known about the risk of its infection to human embryo/fetal development. However, SARS and MERS were associated with negative outcomes, such as miscarriage, preterm birth, intrauterine growth restriction and perinatal death. Here, we raise concerns and possibilities related the harmful potential of SARS-CoV-2 and COVID-19 to pregnancy, discussing symptoms, immunological changes during pregnancy, SARS-CoV-2 mutation rate (and the risks related to it). Finally, we point out recommendations to be performed by the scientific community and health care workers in order to identify and to manage potential risks to pregnant women and their babies

Performance of the Gail and Tyrer-Cuzick breast cancer risk assessment models in women screened in a primary care setting with the FHS-7 questionnaire

Breast cancer (BC) risk assessment models base their estimations on different aspects of a woman’s personal and familial history. The Gail and Tyrer–Cuzick models are the most commonly used, and BC risks assigned by them vary considerably especially concerning familial history. In this study, our aim was to compare the Gail and Tyrer-Cuzick models after initial screening for familial history of cancer in primary care using the FHS-7 questionnaire. We compared 846 unrelated women with at least one positive answer to any of the seven FHS-7 questions (positive group) and 892 unrelated women that answered negatively (negative group). Concordance between BC risk estimates was compared by Bland-Altman graphics. Mean BC risk estimates were higher using the Tyrer-Cuzick Model in women from the positive group, while women from the negative group had higher BC risk estimates using the Gail model. With increasing estimates, discordance also increased, mainly in the FHS-7 positive group. Our results show that in women with a familial history of cancer, the Gail model underestimates risk and the Tyrer-Cuzick seems to be more appropriate. FHS-7 can be a useful tool for the identification of women with higher breast cancer risks in the primary care setting