Evaluation of in vitro embryotoxicity tests for Chinese herbal medicines.

Chinese herbal medicines (CHMs) have been widely used during pregnancy, but feto-embryo safety tests are lacking. Here we evaluated in vitro embryotoxicity tests (IVTs) as alternative methods in assessing developmental toxicity of CHMs. Ten CHMs were selected and classified as strongly, weakly and non-embryotoxic. Three well validated IVTs and prediction models (PMs), including embryonic stem cell test (EST), micromass (MM) and whole embryo culture (WEC), were compared. All strongly embryotoxic CHMs were predicted by MM and WEC PM2. While all weakly embryotoxic CHMs were predicted by MM and WEC PM1. All non-embryotoxic CHMs were classified by EST, MM, but over-classified as weakly embryotoxic by WEC PM1. Overall predictivity, precision and accuracy of WEC determined by PM2 were better than EST and MM tests. Compared with validated chemicals, performance of IVTs for CHMs was comparable. So IVTs are adequate to identify and exclude embryotoxic potential of CHMs in this training set.

Embryotoxicity of Psoralea corylifolia L.: in vivo and in vitro studies.

BACKGROUND: Psoralea corylifolia L. (PC) was commonly used to treat miscarriages clinically. The aim of this study was to examine its embryotoxicity in mice and embryonic stem cells (ESCs). METHODS: Quality control of PC extract including reference marker compounds, pesticide residues, and heavy metals was authenticated with HPLC, Gas chromatography-mass spectrometry (GC-MS), and inductively coupled plasma-mass spectrometry. Pregnant mice were randomly assigned into five groups and dosed with distilled water (G1), PC extract of 2 (G2), 4 (G3), or 8 g/kg/day (G4), and vitamin A (G5). Meanwhile, half maximal inhibitory concentration values for ESCs and 3T3 cells were identified in a cytotoxicity assay, and apoptosis in neuroepithelium was assessed by transmission electron microscopy. RESULTS: In the G4 group, a statistically significant decrease in the total fetus, live fetus, and gravid uterine weight, and increase in the resorbed fetus, postimplantation loss, and neuroepithelial apoptosis as well as maternal liver-weight were found (p < 0.05). CONCLUSIONS: PC extracts at 8 g/kg/day might cause fetal toxicity and maternal liver damage in mice, although it did not cause typical malformation and ESC's cytotoxicity in this experiment. Our data suggested that high dosage and long-term administration of PC preparations may not be safe for pregnant women.

Safety profile of Hoodia gordonii extract: rabbit prenatal developmental toxicity study.

Hoodia gordonii extract was orally administered by gavage to groups of 22 female New Zealand white rabbits from day 3-28 after mating at doses of 0 (control), 3, 6 or 12 mg/kg bodyweight/day. These doses were reached by a dose escalation phase between days 3 and 7 after mating. As well as a vehicle control group, a control group pair-fed to the high dose was also included. On day 29 after mating the females were euthanized and examined. Treatment at 6 or 12 mg/kg/day was associated with a dose-related reduction in feed intake and bodyweight gain. Feed consumption and bodyweight gain was unaffected at 3mg/kg/day. In spite of marked maternal effects at 12 mg/kg/day, reproductive indices were unaffected at all doses and there were no effects on fetal or placental weights and no morphological changes in the fetuses. The no-observed-effect level (NOEL) for developmental effects was therefore 12 mg/kg/day, and the maternal NOEL was 3mg/kg/day. At doses that caused marked maternal effects, H. gordonii extract did not affect embryonic or fetal development in a species that is considered predictive of developmental toxicity in man.

Developmental toxicity of orally administered pineapple leaf extract in rats.

The extract of pineapple leaves (EPL) has anti-diabetic and anti-dyslipidemic effects and can be developed into a promising natural medicine. This study was conducted to evaluate EPL's effects on developmental parameters in order to provide evidence of its safety before potential medical use. Five groups were included: a negative control that was given distilled water daily, a positive control that was dosed 7 mg/kg cyclophosphamide (CP) every two days, and three groups that were respectively dosed 2.0, 1.0, and 0.5 g/kg EPL daily. Female rats were dosed during the organogenesis period of gestation days (GD) 7-17 and terminated on GD 20. A series of parameters were examined. Data revealed that CP significantly reduced maternal body weight gains, caused maternal organ weight alterations, reduced female fertility, disturbed fetal growth and development, and caused marked teratogenic effects on fetal appearances, skeleton and internal organs. Distilled water and the three high doses of EPL did not cause any of the aforementioned effects. This study concluded that orally administered EPL is safe to rats during embryonic development.

Safety assessment of Cordyceps guangdongensis.

Cordyceps guangdongensis as a kind of fungus, has been discovered and cultivated successfully in recent years. However, its safety assessments have not been studied. In this report, a serial of tests for toxicological safety assessments were depicted in details. These tests included bacterial reverse mutation (Ames) study, bone marrow cell micronucleus test in mice, sperm aberration test in mice, teratogenicaction test in rats, acute toxicity test and 13-week oral toxicity study in rats. After a profound analysis of these tests, it clearly demonstrated that C. guangdongensis did not have any mutagenic, clastogenic nor genotoxic effects; the oral LD50 of the biomass in rats was greater than 15 g/kg body weight; the no-observed adverse-effect-levels (NOAEL) was 5.33 g/kg body weight according to the 13-week oral toxicity analysis. Therefore, a conclusion can be drawn that C. guangdongensis is considered safe for long term consumption.

Effects of Ginkgo biloba extract on the embryo-fetal development in Wistar rats.

BACKGROUND: Ginkgo biloba extract (GBE) is an herbal medicine used for treating neurodegenerative diseases, cerebrovascular insufficiency, peripheral arterial occlusive disease, and also vestibular disturbance. Some components of GBE have presented estrogenic effects and, in a previous study, high dosages of GBE caused intra-uterine growth retardation in fetuses of Wistar rats treated during the fetogenesis period. METHODS: Pregnant Wistar rats were treated, through gavage, with different dosages of aqueous GBE (3.5, 7.0, and 14.0 mg/Kg/day), during the tubal transit and implantation period. Rats were killed on the 15th day of pregnancy and the following parameters were evaluated: clinical symptoms of maternal toxicity; maternal body weight; feed and water intake; maternal liver, kidney, and ovary weights; number of corpora lutea; implants per group ratio; pre- and post-implantation loss per group ratio; live fetuses mean; dead fetuses percentage; fetus and placenta weight per offspring ratio; and fetal external malformation. RESULTS: No significant alteration was found for both the maternal and embryonic parameters evaluated. CONCLUSIONS: The GBE treatment in pregnant Wistar rats, during the tubal transit and implantation period, caused no toxic effect on the maternal organism and did not induce embryonic death, growth retardation, and/or fetal malformations.

Improved methodology for identifying the teratogenic potential in early drug development of hERG channel blocking drugs.

Drugs blocking the potassium current IKr of the heart (via hERG channel-inhibition) have the potential to cause hypoxia-related teratogenic effects. However, this activity may be missed in conventional teratology studies because repeat dosing may cause resorptions. The aim of the present study was to investigate an alternative protocol to reveal the teratogenic potential of IKr-blocking drugs. The IKr blocker astemizole, given as a single dose (80 mg/kg) on gestation day (GD) 13 to pregnant rats caused digital defects. In whole rat embryo culture (2h) on GD 13, astemizole caused a decrease in embryonic heart rate at 20 nM, and arrhythmias at 200-400 nM. Cetirizine, without IKr-blocking properties, did not affect the rat embryonic heart in vitro. The present study shows that single dose testing on sensitive days of development, together with whole embryo culture, can be a useful methodology to better characterize the teratogenic potential of IKr-blocking drugs.

[Importance of the Teratogen Information Service in Bahia, Brazil, for prevention of congenital malformations: an initial four-year review]. / A importância do Serviço de Informações sobre Agentes Teratogênicos, Bahia, Brasil, na prevenção de malformações congênitas: análise dos quatro primeiros anos de funcionamento.

Teratogenic agents are defined as physical, chemical, or biological agents or nutrient deficiencies that lead to fetal structural or functional alterations. Information on the effects of exposure to teratogens during pregnancy is of the utmost importance. In order to achieve this goal, in 2001, the Bahia State Teratogen Information Service was created in the Medical Genetics Department at the University Hospital of the Federal University in Bahia. The current paper aimed to describe the first four years of operation in the service. From March 2001 to May 2005, the service was consulted by telephone, fax, and e-mail. During this period, 408 queries were made, for a total of 1,091 different reasons. Most queries were made by pregnant women and health care professionals. Hair products, herbal teas, and misoprostol were the most widely investigated agents. The low number of queries (average 1/day) shows the need for more awareness-raising on the risks posed by the various agents.

A importância do Serviço de Informações sobre Agentes Teratogênicos, Bahia, Brasil, na prevenção de malformações congênitas: análise dos quatro primeiros anos de funcionamento / Importance of the Teratogen Information Service in Bahia, Brazil, for prevention of congenital malformations: an initial four-year review

Agente teratogênico é definido como o agente físico, químico, biológico ou estado de deficiência que, durante a vida embrionária, leva a alteração na estrutura ou função do concepto. Informações sobre a conduta a ser tomada no caso de exposições a teratogênicos durante a gestação são imprescindíveis. Com essa finalidade, em 2001, foi implantado o Serviço de Informações sobre Agentes Teratogênicos da Bahia (SIAT-BA), localizado no Serviço de Genética Médica do Hospital Universitário Professor Edgard Santos da Universidade Federal da Bahia. O objetivo é descrever as características do atendimento do SIAT-BA nos seus primeiros quatro anos de funcionamento. As consultas foram realizadas através do contato via telefone, fax ou e-mail, entre março de 2001 e maio de 2005. Nesse período, o SIAT-BA recebeu 408 consultas, totalizando 1.091 motivos. A maioria das consultas foi realizada por gestantes e profissionais de saúde. Produtos para cabelo, chás e misoprostol foram os agentes mais investigados. O pequeno número de consultas (1/dia) indica a necessidade de maior divulgação do serviço e da conscientização da população sobre os riscos oferecidos pelos diversos agentes.

Teratogenic agents are defined as physical, chemical, or biological agents or nutrient deficiencies that lead to fetal structural or functional alterations. Information on the effects of exposure to teratogens during pregnancy is of the utmost importance. In order to achieve this goal, in 2001, the Bahia State Teratogen Information Service was created in the Medical Genetics Department at the University Hospital of the Federal University in Bahia. The current paper aimed to describe the first four years of operation in the service. From March 2001 to May 2005, the service was consulted by telephone, fax, and e-mail. During this period, 408 queries were made, for a total of 1,091 different reasons. Most queries were made by pregnant women and health care professionals. Hair products, herbal teas, and misoprostol were the most widely investigated agents. The low number of queries (average 1/day) shows the need for more awareness-raising on the risks posed by the various agents.

Comparison of the potential for developmental toxicity of prenatal exposure to two dietary chromium supplements, chromium picolinate and [Cr3O(O2CCH2CH3)(6(H2O)3]+, in mice.

BACKGROUND: Chromium(III) is generally thought to be an essential trace element that allows for proper glucose metabolism. However, chromium(III) picolinate, Cr(pic)3, a popular dietary supplement form of chromium, has been shown to be capable of generating hydroxyl radicals and oxidative DNA damage in rats. The cation [Cr3O(O2CCH2CH3)(6(H2O)3]+, Cr3, has been studied as an alternative supplemental source of chromium. It has been shown to increase insulin sensitivity and lower glycated hemoglobin levels in rats, making it attractive as a potential therapeutic treatment for gestational diabetes. To date, no studies have been published regarding the safety of Cr3 supplementation to a developing fetus. METHODS: From gestation days (GD) 6-17, mated CD-1 female mice were fed diets delivering either 25 mg Cr/kg/day as Cr(pic)(3), 3.3 or 26 mg Cr/kg/day as Cr3, or the diet only to determine if Cr3 could cause developmental toxicity. Dams were sacrificed on GD 17, and their litters were examined for adverse effects. RESULTS: No signs of maternal toxicity were observed. No decrease in fetal weight or significantly increased incidence of skeletal defects was observed in the Cr3 or Cr(pic)3 exposed fetuses compared to the controls. CONCLUSION: Maternal exposure to either Cr(pic)3 or Cr3 at the dosages employed did not appear to cause deleterious effects to the developing offspring in mice.

Teratogenicity study of the dihydroorotate-dehydrogenase inhibitor and protein tyrosine kinase inhibitor Leflunomide in mice.

Leflunomide is an immunosuppressive agent that inhibits de novo synthesis of pyrimidine nucleotides and the activity of protein tyrosine kinase. This study examined the teratogenicity of Leflunomide in mice. Pregnant mice were treated orally with Leflunomide at a dose of 10, 30 or 70 mg/kg/day from day 6 to 15 of pregnancy. At 70 mg/kg, all embryos were resorbed and no live fetuses were detected. At 30 mg/kg, Leflunomide reduced fetal viability, and increased the incidence of multiple external, skeletal and visceral malformations. Characteristic external malformations were neural tube defects, cleft palate and tail deformities. Limb malformations were observed in a small number of fetuses. Skeletal examinations revealed malformations of cervical to sacral vertebrae, ribs and sternebrae. In the viscerae, the main anomalies were membranous ventricular septum defect and persistent truncus arteriosus. The results of this study indicate that Leflunomide administered at 30 mg/kg on days 6 to 15 of pregnancy can induce craniofacial malformations and deformities of the axial skeleton, heart and great vessels in mice.

Embryotoxicity study of ginsenoside Rc and Re in in vitro rat whole embryo culture.

BACKGROUND: Pregnant women commonly consume ginseng. However, there is little data concerning the effects of ginseng on early pregnancy. METHODS: Rat embryos were exposed in vitro to different concentrations of Rc and Re from day 9.5 to day 11.5 after conception. Embryos were scored for growth and differentiation at the end of the culture period. RESULTS: Embryos exposed to 50.0 microg/ml Re had significantly lower median morphological score (29.0 versus 48.0), fewer number of somites (15.0 versus 21.0), and smaller yolk sac diameter (3.5 versus 4.1 mm) and crown-rump length (CRL) (2.9 versus 3.4 mm) compare to control embryos. There was no significant difference between embryos exposed to 5.0 microg/ml Re and control embryos. There was also no difference in the biometric and morphologic parameters among control and embryos exposed to 5.0 and 50.0 microg/ml Rc. CONCLUSION: There is a significant variability in embryotoxic effects of different ginsenosides. Further studies to evaluate the synergistic embryotoxic effects of ginsenosides are warranted.

Guía de práctica clínica basada en la evidencia para el manejo de la paciente embarazada que requiera tratamiento endodóntico / Evidence-based clinical practice guide for the management of the pregnant patients requiring endodontic treatment

Antecedentes: el tratamiento odontológico de los pacientes sistémicamente comprometidos tiene cada vez más importancia en el campo de la salud bucal. El sistema general de seguridad social actual en Colombia crea la necesidad de establecer protocolos para el diagnóstico y tratamiento de las diferentes patologías, con evidencia científica para el mejoramiento en la calidad de la atención de los usuarios. La mayoría de los protocolos que existen actualmente para el manejo del paciente con compromiso sistémico y diangóstico de patología bucal, se presentan como revisiones teóricas con poca aplicabilidad clínica o con una inapropiada sustentación científica; de igual forma, se encuentra diversidad de procedimientos terapéuticos para abordar una mismma patología, generando serias dificultades para unificar criterios de planes de tratamiento en este grupo de pacientes. Objetivo: diseñar guías de práctica clínica bassadas en la evidencia para el manejo del paciente sistémicamente comprometido que requiera tratamiento. En este artículo se presenta una revisión que concierne a la condición sistémica del embarazo. Métodos: revisión sistemática de la literatura y desarrollo de guías de práctica clínica con metodología de medicina basada en la evidencia. Resultados: desarrollo de la guía de práctica clínica basada en la evidencia para el manejo de la paciente embarazada que requiera tratamiento endodóntico. Conclusiones: la realización de esta guía ofrece una ilustración práctica de los puntos críticos de la toma de decisiones para el tratamiento endodóntico de la paciente embarazada (uso de anestésicos, analgésicos, antibióticos y toma de radiografías) y garantiza que éstas sean tan realizables y éticas como sea posible

Safe prescribing practices in pregnancy and lactation.

Midwives and other health care providers face a dilemma when a pregnant woman develops a condition that usually is treated with a pharmacologic agent. Understanding of basic teratology associated with drugs as well as the FDA categorization of agents can assist professionals in recognizing which pharmaceuticals should be used or avoided. In addition to reviewing teratology, this article addresses the use of common drugs for the treatment of upper respiratory conditions, minor pain, gastrointestinal problems, psychiatric illnesses, and neurologic disorders. In each category, current evidence is presented pertaining to which agents should be recommended for pregnant women.

Use of the adult developmental relationship in prescreening for developmental hazards.

The overwhelming majority of chemicals already in commerce or brought into use each year have not been evaluated for their potential to adversely affect in utero development. Data from those that have been evaluated thus far in pregnant laboratory animals establish that most, but not all, were no more hazardous to the conceptus than they were to adult homeostasis. Most did not need standard developmental toxicity testing because avoidance of adult toxic exposure levels would have precluded abnormal in utero development. The six general principles of teratology when modified, expanded, and placed into this type of context of contemporary developmental toxicology allow an updating of the present testing sequence which was devised prior to 1966. The developmental hazard index (A/D ratio) calculated from the adult and developmental NOELs of standard Segment II evaluations is predicted by in vitro means. This determination, when coupled with adequate considerations of exposure can be used to prioritize chemicals for more elaborate developmental toxicity tests. Those chemicals with large ratios, i.e., disruptive of embryogenesis at treatment levels too low to produce overt effects in the mother and/or with significant concern regarding exposure, can be identified and tested in pregnant laboratory animals as high priority items. Those with low ratios and those for which there is a low level of concern regarding exposure potential also can be identified and are not high priority items for testing in pregnant animals. The proposed tier system establishes priorities of testing based on exposure and the concept of target organ toxicity applied to the embryo. It provides intensive in vivo evaluations of those chemicals for which developmental effects testing is most needed and avoids use of resources and animals for unnecessary testing of agents that do not pose threats to the conceptus.

Evaluating the alleged teratogenicity of environmental agents.

The criteria used to regulate exposure to a drug or chemical are different from those employed to implicate an agent as a human teratogen in general and in an individual patient. The importance of regulating exposures and in implicating teratogenicity merit special attention to the problems of educating physicians and the lay public, scientifically evaluating teratogenicity, preventing unnecessary abortions, and protecting the public.