AT THE BORDER:
Protect Pregnant Migrant Mothers and Their Offspring OLIVIA SCHULIST | MARCH 2020 The thrifty phenotype hypothesis postulates that key
environment prefaces the the types and magnitudes of
elements of an individual's metabolism are established
stressors that a given developing infant will encounter over
during critical periods of life in an evolutionary attempt to
their lifetime. In contrast, a mismatch occurs when the
prepare bodies for their future environments. Stress during
expression of an individual is optimized in early life for an
in utero and early postpartum development, especially
environment unlike that in which the individual will
during the second trimester of pregnancy, increases
eventually reside. For instance, maternal undernutrition
offspring risk for chronic diseases like cardiovascular
epigenetically programs offspring propensity for metabolic
disease and diabetes, which are the first and seventh most
pathways typifying pre-diabetes and heart disease when
common causes of death in the United States, respectively.
affected offspring eventually reside in calorically-dense
Stress
maternal
environments. Calorie and protein restriction during the
psychological distress and malnutrition. Immigrant pregnant
perinatal period is correlated with altered methylation of
mothers held in detainment centers at the United States
the promoters of POMC, glucocorticoid, angiotensin
border may be uniquely susceptible to psychological and
receptor, leptin, FTO, MC4R, PPARɑ, PPARγ genes. These
physiological
epigenetic
epigenetic modifications alter the roles of adiponectin,
determinants of health and disease can be transferred from
insulin, and leptin molecules in the body, consequently
parent to offspring intergenerationally, the lack of social
altering the size and density of neurons in hypothalamic
support and poor nutrition inflicted upon these mothers may
regions of the brain. Hypothalamic alterations affect energy
yield adverse epigenetic fetal programming with effects
balance systems by reducing leptin and insulin signalling.
lasting centuries, if not longer.
Tissue and organ functions then shift to accommodate
can
take
many
distress.
forms,
Because
including
lifetime
slowed growth. Peripheral nervous system innervations to Fetal programming is the process by which the expression
adipose and gut tissues program the body to accumulate
of an individual’s genes is modified to reflect environmental
energy in states of nutritional excess. Because patterns of
demands. These “epigenetic” modifications include histone
histone
modifications, DNA demethylation and DNA acetylation;
acetylation patterns can be transferred intergenerationally,
each process can yield long-lasting changes in protein
various types of stressors during pregnancy can have
synthesis and function throughout the body. Alterations to
lifelong effects in a woman’s immediate offspring and
metabolic set points are adaptive when the in utero
subsequent lineage.
modification,
DNA
methylation,
and
DNA
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