Effects of improved on-farm crop storage on DNA methylation of mothers and their infants: evidence from a randomized controlled trial in Kenya.

BACKGROUND: Stress during pregnancy can lead to adverse maternal and infant health outcomes through epigenetic changes in the hypothalamic-pituitary-adrenal axis. Among farmers in low-income countries, one important stressor is food insecurity, which can be reduced using hermetic storage bags. This study aimed to determine, for the first time, whether a hermetic storage bag intervention during pregnancy positively affects maternal and infant DNA methylation of the hypothalamic-pituitary-adrenal axis-related genes FKBP5 and NR3C1. We further analyzed whether anthropometrics, stress, and mental health were associated with DNA methylation. METHODS: This study was part of a larger matched-pair randomized controlled trial focusing on the impact of improved on-farm storage on food security, poverty, and net income of smallholder farming households. A total of N = 149 mothers were recruited by telephone and invited to attend a study appointment at health facilities in Kakamega County, Western Kenya, with their infants in April or May 2021. During the appointment, anthropometric measurements were taken, questionnaires on stress and mental health were administered, and saliva samples were collected. Logistic and multiple linear regression were used to examine the effect of the intervention and related measures on DNA methylation. RESULTS: Mothers in the intervention group showed higher mean NR3C1 methylation levels than those in the control group, corrected for multiple testing. Maternal postpartum body mass index was positively associated with infant NR3C1 CpG3 DNA methylation. The more stressful life events a mother had experienced in the previous 12 months (including during pregnancy), the lower her FKBP5 CpG3 methylation levels. CONCLUSIONS: Food insecurity and stressful life events during pregnancy seem to exert significant effects on maternal DNA methylation. While these stressors did not appear to impact infant DNA methylation in the present study, maternal postpartum body mass index was significantly related to infant methylation. These findings suggest that while infants may be protected from excessive maternal glucocorticoids by placental barrier activity, maternal metabolic status is still reflected in their epigenetic make-up. Trial registration This study was part of a larger matched-pair randomized controlled trial on the impact of improved on-farm crop storage on welfare, nutrition, and human health. Registration can be found in the American Economic Association (AEA) RCT Registry, RCT ID: AEARCTR-0005845.

The association between prenatal famine, DNA methylation and mental disorders: a systematic review and meta-analysis.

BACKGROUND: Undernutrition in pregnant women is an unfavorable environmental condition that can affect the intrauterine development via epigenetic mechanisms and thus have long-lasting detrimental consequences for the mental health of the offspring later in life. One epigenetic mechanism that has been associated with mental disorders and undernutrition is alterations in DNA methylation. The effect of prenatal undernutrition on the mental health of adult offspring can be analyzed through quasi-experimental studies such as famine studies. The present systematic review and meta-analysis aims to analyze the association between prenatal famine exposure, DNA methylation, and mental disorders in adult offspring. We further investigate whether altered DNA methylation as a result of prenatal famine exposure is prospectively linked to mental disorders. METHODS: We conducted a systematic search of the databases PubMed and PsycINFO to identify relevant records up to September 2022 on offspring whose mothers experienced famine directly before and/or during pregnancy, examining the impact of prenatal famine exposure on the offspring's DNA methylation and/or mental disorders or symptoms. RESULTS: The systematic review showed that adults who were prenatally exposed to famine had an increased risk of schizophrenia and depression. Several studies reported an association between prenatal famine exposure and hyper- or hypomethylation of specific genes. The largest number of studies reported differences in DNA methylation of the IGF2 gene. Altered DNA methylation of the DUSP22 gene mediated the association between prenatal famine exposure and schizophrenia in adult offspring. Meta-analysis confirmed the increased risk of schizophrenia following prenatal famine exposure. For DNA methylation, meta-analysis was not suitable due to different microarrays/data processing approaches and/or unavailable data. CONCLUSION: Prenatal famine exposure is associated with an increased risk of mental disorders and DNA methylation changes. The findings suggest that changes in DNA methylation of genes involved in neuronal, neuroendocrine, and immune processes may be a mechanism that promotes the development of mental disorders such as schizophrenia and depression in adult offspring. Such findings are crucial given that undernutrition has risen worldwide, increasing the risk of famine and thus also of negative effects on mental health.

Effects of improved on-farm crop storage on perceived stress and perceived coping in pregnant women-Evidence from a cluster-randomized controlled trial in Kenya.

BACKGROUND: Food insecurity can be harmful to pregnant women, as pregnancy is a challenging period with increased maternal nutritional requirements to ensure optimal fetal development and health of the mother. Whether food insecurity negatively affects maternal health may depend on how stressful pregnant women perceive this food insecurity to be and how strongly they believe they can cope with it. In Sub-Saharan Africa (SSA), pregnant women from smallholder households suffer from food insecurity due to post-harvest losses (PHL), i.e., loss of crops because of inadequate storage. An agricultural intervention that improves crop storage has been shown to reduce food insecurity. However, it remains to be determined whether this agricultural intervention (treatment) has an additional positive effect on pregnant women's perceived stress levels and coping abilities. This study examines whether pregnant women from treatment households experience lower perceived stress levels and higher perceived coping abilities compared to pregnant women from control housholds. METHODS AND FINDINGS: In a randomized controlled trial (RCT), short message service (SMS)-based mobile phone surveys were conducted to assess the causal effect of a food security intervention (improved on-farm storage of maize) on perceived stress and coping in pregnant women from smallholder households. Pregnant women were identified through these monthly surveys by asking whether someone in their household was currently pregnant. The significant results revealed that pregnant women from treatment households experienced more perceived stress but better perceived coping abilities compared to pregnant women from control households. Uncertainty due to lack of experience, this might have contributed to the higher perceived stress, as the women could not easily judge the benefits and risks of the new storage technology. However, the technology itself is a tangible resource which might have empowered the pregnant women to counteract the effects of PHL and thus food insecurity. CONCLUSION: Our findings indicate that pregnant women from treatment households had higher perceived coping abilities but experienced more perceived stress. More research is needed on how this technology impacts maternal mental health in a broader sense and whether biological mechanisms, such as epigenetics, may underlie this association.