39th Annual Meeting of

the European Teratology Society

Korean Motherisk Program

J.Y.Han

Gent, Belgium

ETS education course

“Omics for beginners”

paramount importance in reproductive toxicology research

toxicogenomic and metabolomic data as well as bioinformatics is expected to play an increasing role for reaching the ultimate goal of chemical safety for man

Currently, there are 10,000 to 30,000 chemicals in world-wide commerce in need of hazard data for assessing potential reproductive toxicity health risks. The traditional animal study designs cannot accommodate the evaluation of this large number of chemicals and bioinformatics technologies are currently being developed to make the goal of chemical safety for man reachable.

I. Exploiting the Revolution: Mouse Genetic and Genomic Resources for Reproductive Health Research.

Dr. Lee B. Smith - MRC, Edinburgh U.K

II. Toxicogenomic Approaches used in Developmental ToxicologyDr. Joshua F. Robinson - RIVM, The Netherlands

III. MetabolomicsDr. Elwin.R. Verheij - TNO, Zeist, The Netherlands

IV. HTS and Computational Modeling for Developmental Toxicity

Dr. Thomas B. Knudsen - USEPA Research Triangle Park, NC, USA

ETS symposium 1 - maternal and childhood asthma:causes, consequences and treatment

Asthma: Chronic inflammatory disease of lower airwayBronchial obstruction Symptom: wheezing, shortness of breath, chest tightness, cough

Inflammation: 특이 싸이토카인( IL-4, IL-5, IL-13)을 내는Type 2 helper T cells에 의해서 가속됨.

이들 싸이토카인이 airway에 염증세포들(eosinophils, neutrophils 등)을 chronic infiltration시킴

Prevalence : 4-8% in USA

Asthma, asthma medications and their effects on maternal/fetal outcome during pregnancy

Rocklin RE

Effect of pregnancy on maternal asthma

Increased estrogen Increased pregesterone B2-adrenoreceptor hypo-responsiveness Female fetus Altered immune function

1/3 악화 1/3 변화 없음 1/3 호전

Effects of maternal asthma on pregnancy and perinatal outcomes

Lung inflammation Maternal hypoxia Altered placental function Fetal gender Asthma exacerbations

Low birth weight Preterm labor Preeclampsia C/S

Reproductive issues in the development of asthma medications

Tx goal: maintain control of asthma for maternal health and quality of life as well as normal fetal maturation

I. Inflammation control : inhaled corticosteroid, leukotrien inhibitors, chromones

II. Relieve sx : B2-agonisttheophylline

Anti asthma medications의 development에 고려점

I. Toxic considerations : adverse fetal outcome

Route of administration Metabolism Dose Whether the agent crosses the placenta at the point of development

at the time of exposure Pharmacologic activity Non-target mediated effects Binding affinity to target in relation to inactive or active forms of the

receptors Toxicokinetics

II. VLA4 antagonism as a specific example of issues related to asthma drug development

Risk evaluation associated with asthma medication use during pregnancy

1. General considerations : Risk and benefit of asthma medication

2. Human data :RCT, generally not feasible Case-control study, Cohort studyDo not by themselves prove causalityOften limited by inadequate sample size

3. Animal data :Animal developmental toxicology experiments Designed to maximize the potential toxic effects by using large doseNegative result: a low potential for human development toxicity Positive result: less predictive for human toxicity

(species difference, clinically irrelevant high dose, maternal toxicity?)

Drug label categories and step therapy recommendations

단점: paucity of adequate and well controlled data in humanOver reliance on animal dataClinical interpretation of C is very difficultRoute of administration와 임싞중일어나는 약물의 약동학과약력학을 고려하지 않음

Inhaled corticosteroid(budesonide) : B

ACAAI-ACOG recommendations for pharmacological step for chronic asthma during pregnancy

- 임싞 시 사용될 수 있는 약: inhaled corticosteroids, theophylline, cromolyn, long acting b2 agonist, leukotriene antagonist(monterukast, zafirlukast)

- Oral steroid: maintain on lowest effective daily dose of steroid

Safety of asthma medication during pregnancy

T4

Maternal and childhood asthma: Risk factors, interactions,and ramifications

Dietert RR

Fetal and early neonatal development: critical period

“Barker Hypotheisis”: Prenatal environmental determination of Later life diseas

Recent examples of early life environmental determinations

1. Developmental Pb on specific childhood neurobehavior outcomes2. Fetal alcohol on CNS3. Developmental PCBs(polycyclic chlorinated biphenys) on adult

pregnancy4. Arsenic and resistance to infectious disease5. Prenatal stress on the HPA axis6. Undernutrition and cardiovascular diseas7. Pesticides and neurodegenerative conditions8. Developmental estrogens and risk of prostate cancer9. Developmental high fat intake and liver disease10. Low vitamin D level and GI tr allergy

Maternal and childhood asthma - Risk factors

Maternal asthma: potential implications

A family history of atopy and asthma: inheritance of allelles driving Th3-bias and skewed inflammatory responses

not pure due to 1. epigenetic alterations-several generations2. environmental risk factors-differential effects

Asthma management in pregnancy : err

Th-2 biased environment : exacerbate sx of Th2-associated disease

Immune dysfunction based-disease and childhood

¼ of children : immune dysfunction based conditions(asthma, autoimmune ds, inflammatory conditions)

Childhood asthma : 선진국에서 최근 크게 증가

Childhood asthma : 25.9%

Risk factors for the child

“largely developmental disease” : its origin in early life

Genetic factors- alleleic and epigenetic

alleric varients of gene encoding cytokines, cytokine receptors 등in animal model, specific genotypes: predispose for Th2-biased adaptive immune responses & hyperinflammatory response in tissuegenes involved : related to immune, inflammatory signaling

and/or functional response examples: minor allelle of Nrf2, common allele for IL-13

IL-1 receptor like 1 polymorphisms, NOD1 and NOD2alleles for both TLR-2 and TLR-4 – traffic related air pollutants

Interactions between genetic and environmental factors: maternal and child polymorphism for antioxidant status vs prenatal paracetamol(acetaminophen) – affected risk for asthma

Study of epigenetics and potential transgenerational effects : infancy

Environmental risk factors

Safety testing gap for childhood asthma

Asthma : most common chronic condition of childrengreatest number of school absence for chronic disease입원 치료의 3번째 원인Annual cost : 18 billion dollars

Immunotoxicity safety testing for childhood allergy and asthma: Not routine for most drugs and chemicals“Safety testing gap”

Outcome of the gap: most children must be treated for childhood asthma rather than benefiting from an aggressive safety testing program to prevent childhood asthma one solution: same level of attention for drug development

Endpoints to monitor the management of childhood allergy and asthma : 천식의 위험을 스크린 하는데 유용

levels of IgE antibody, T2 cytokines, eosinophils in bronchial lavage, production of inflammatory mediators, chemokine in the airways, alterations in pattern recognition receptors, changes in bronchial reactivitiyand architectiure

스크린이 효율적이기 위해서

1. age-relevant immunotoxicity safety screening be widely employed in evaluating the safety of drugs and chemicals.

2. Immune respiratory challenge (eq. respiratory viral infection) 포함되어야 함.

Consequence for children diagnosed with asthma

Childhood asthma: a significant lifelong health burden beginning in children and entryway to potential additional chronic disease

Child with asthma is a high risk group for later childhood and adult onset conditions: allergic rhinitis, atopic dermatitis, otitismedia, increased respiratory infections, behavioral disorders, obesity, olfactory disorders, and lung cancer

The elevated risks be connected to fundamental immune dysfunction associated with childhood asthma: Th2 biased responses, improper innate immune maturation, improperly regulated inflammation in the airways, other tissues than can affect metabolism and risk of lung cancer, cytokine imbalances that can affect sleelppatterns, moods and sensory functions

ETS symposium 2 – Prenatal and postnatal causes for obesity and their complications later in life

Asher Ornoy

PGDM & GDM : Sp abortion, IUFD, congenital anomalies, neurodevelopmental problems, increased risk of perinatal complications

또핚, fetal growth disturbance: increased or decreased BW.

Optimal control of maternal blood glucose: reduce these changes

Metabolic syndrome: hypertension, cardiovascular complications, type 2 diabetes

Excessive maternal overweight and obesity or excessive wt gain:

Increased obesity and complications in the offspring.

FGR and Macrosomia : “metabolic syndrome”

Mechanisms underlying these long term effects on growth:

Insulin resistance, fetal hyperleptinemia,

hypothalamic changes, probably epigenetic changes

Prevention of metabolc syndrome:

Tight dietary control and physical activity in the children born to

obese or diabetic mothers

Long-term effects of FGR and of Macrosomia- the metabolic syndrome

Reaven(1988) :

Insulin resistance and secondary hyperinsulinemia –etioology of diabetes type 2, cardiovascular disease, hypertension- 3 components of main complications of FGR and macrosomia at

adulthood- then called “ syndrome X, later modified to the “metabolic

syndrome” - glucose intolerance,

increased insulin secretion, increased blood triglyceride, decreased HDL, hypercholesterolemia, cardiovascular disease, diabetes type 2

Thrifty phenotype hypothesis:

- epidemiological association between poor fetal growth, type 2 diabetes, metabolic syndrome result from the effects of poor nutrition in early life, which produces permanent changes in glucose insulin metabolism

reduced capacity for insulin secretion and insulin resistance

obesity, aging and physical inactivity : cardiovascular and metabolic complications

the result of adaptational change of the fetal endocrine-metabolic mechanism to the impaired intrauterine milieu to assure survival in the short term

FGR이 일어났던 time과 정도에 따라, 각 개인들에서

metabolic syndrome의 parameter가 다르게 나타남 :

Symmetric type of FGR : arterial hypertension later in life

Asymmetric type of FGR : glucose intolerance and type 2

diabetes.

GDM and Obesity associated macrosomia : strong predictor

of metabolic syndrome

Mechanisms of long term outcome of children born SGA or macrosomic

1) The “Thrifty” genes or “Barker” hypothesis(metabolic syndrome)

2) Insulin resistance

3) Changes in leptin secretion and leptin insensitivity

4) Hypothalamic programming

5) Epigenetic changes

1) The “Thrifty” genes or “Barker” hypothesis(metabolic syndrome)

-“thrifty phenotype” hypothesis : Hales and Barker 1992

407 men Hertfordshire, England 1920-1930 226 men and women Preston, England 1935-1943

Size at birth and 1year of agePrevalence of “thrifty syndrome” fell progressively in both men and women with the increase in birth weight

At birth, subjects with the thrifty syndrome : small head circumference, at 1year low weight and below-average dental eruption.

Type 2 diabetes and hypertension : common origin in sub-optimal growth and development in in utero

2. Insulin resistance

Insulin resistance : fundamental and most important underlying problem in the pathogenesis of the “metabolic syndrome”

Insulin resistance cause insulin over-secretion followed by insulin deficiency, which is the basic pathogenesis of obesity and type 2 diabetes

In pregnant women with GDM, maternal hyperglycemia(diabetes) induces fetal hyperinsulinemia. Elevated fetal insulin affect its hypothalamic development.

Insulin in the brain decrease food intake, while insulin depletion(or resitance) may promote hyperphagia.

Fetal intra-cerebral injection of insulin : decline of the NPY(Neuropeptide Y) protein, NPY increase food intake.

These effects on the fetal brain : long lasting, affecting hypothalamic organization and metabolism.

Increased insulin levels increase leptin secretion by adipocytes, further decreasing food intake.

3) Changes in leptin secretion and leptin insensitivity

Leptin : hormone secreted by the adipose tissue which acts as a sensor of

body fats.

Secteted in levels that directly correlate with body fat stores

Acts as an anorexogenic hormone in the brain

Controlling feeding behavior by specifically decreeing appetite

Leptin or leptin receptor animal or man : early onset obesity

Main action : in the hypothalamus

hypothalamus arcuate nucleus’ neuron : express several

peptides related to feeding behavior

“leptin resistance” : situation where leptin is elevated in the blood of obese individualoccur in many obese people where food intake is not reduce in spite of the increased leptin levels

different explanation: impaired transport through the BBB, impairment of leptin signaling by the chronic high level of leptin

Placenta produces a significant amount of leptinInsulin treatment increase the production of leptin by the placenta, as a fetal cerculating leptin

Fetal hyperleptinemia(by maternal obesity or maternal increased wt gain) : significnat influence on the fetal hypothalamus and on future

energy homeostasis

Mice lacking leptin : increased appatite, obese and become diabetic due to development of insulin resistance

4) Hypothalamic programming : the role of fetal nutritional imbalance

Hypothalamus : regulate food intake and energy balance

Different area for the regulation :ventromedial hypothalamic nucleus : satiety lateral hypothalamic area : feeding center

In these area, neurotransmitters(norepinephrine, serotonin, GABA ext) are secreted.

이들 neurotransmitter의 metabolism의 변화는 food intake에 영향

Most important area : arcuate nucleus- have both central and peripheral connections also containing leptin sensitive neuron.

NYP : a 36 amino acid peptidereleased from the nerve terminals of the arcuate nucleus and in other part of cerebral cortex.involve in vasomotor reactivity, sexual function, promote feeding and obesity

POMC(proopiomelanocortin derived peptides) : inhibit feeding glycoprotein which serves as multihormonal precursorof corticotropin, lipotropins, melanotropins, dendorphins

The neurons secreting NPY of POMC have synapses with neurons located in other parts of the hypothalamus associated food regulations, also with neurons in the cerebral cortex, thalamus and brain stem.

Receive information from the periphery mainly through leptin and insulin.

Nutritional change of developing fetus( resulting in FGR or macrosmoia) will induce long lasting changes in the hypothalamic centers that control food intake.

Most hypothalamic connections in the human fetus seem to develop during the second half of pregnancy

Hypothalamic disturbances may cause obesity and diabetes

5) Epigenetic changes

How do intrauterine growth disturbances remain as a stable memory in the later biology and behavior of the offspring?

New understanding of genome-function is emerging.

Genome-functionality is determined by DNA sequence, the

timing and expression of the genes.

Epigenome: molecular mechanisms that govern gene

expression in a time- and cell-type dependant fashion.

Early environmental exposures such as high glucose or

maternal obesity and overfeeding during pregnancy alter the

programming of genes by epigenetic markings, resulting in a

long term imprint on gene expression that lasts into adulthood.

Severe reprogramming of critical genes for development may result in teratogenicity or early neurodevelopmental deficit, Whereas responses in the physiological range would increase the risk of development of neurobehavioral problems, obesity and thye 2 diabetes later in life.

Homeobox PdX1 undergoes progressive epigenetic silencing in beta cells in rodents that were exposed to intrauterine growth retardation and are prone to develop diabetes.

Streptozocin induced type 1 diabetes in the rat results in genral DNA hypomethylation in the liver.

Gluckman and Hanson: fetal undernutrition causes epigenetic changes that can later in life, when nutrition is adequate or high, cause metabolic imbalance resulting in the typical “metabolic syndrome”

Stevens : maternal undernutrition may induce epigenetic changes in the offspring, especially in the hypothalamic neuropeptide(NPY, POMC) genes that regulate energy balance.

One of the most important tasks of preventive medicine in the 21st century

ETS-T Debate- “All Mixed up about Mixtures:How Big of a problem and What to Do about it”

Teratology society : low level of mixtures is OK

European teratology society :

sensitive endpoints of antiandrogen1. anogenital distance 2. nipple retention 3. malformation : hyposphadia

0% + 0% + 0% = ~60%

“Paracelsus” : dose make poisonso, cumulative dose make risk.

Elsevier Award lecture :

Fetal malformations and early embryonic gene expression response in Cynomolgus monkeys maternally exposed to thalidomide

Makoto Ema

ETS Award lecture

“The Male conundrum”

John Tesh

Conundrum : confusion

BC 600, 피타고라스 : male essence for offsprings

아리스토텔레스 : Theory of epigenesisSoul guide gradual epigenetic development

- - -

1993, Male mediated developmental toxicity

Male Female

Offsprings

Free Communications

In utero exposure to antiepileptic drugs: Cognitive development and functioning of the child

Epilepsy : 198 Control 210

Sodium valproate (n=51) : lower global cognitive ability, memory, attention, rate of learning,

language score

Dose dependent relationship was found, above 800mg/d increased cognitive impairment.

Neurodevelopmental disorders of valproate vs control : OR 7.28

No significant association with lower cognitive or neurodevelopmentaldisorders was founded born to women with untreated epilepsy(n=25) , carbamazepine(n=50), lamotrigine(n=29)

University of Manchester, UK

Poster