Environmental mismatch and obesity in humans: The Jerusalem Perinatal Family Follow-Up Study

Metabolic and fecal microbial changes in adult fetal growth restricted mice

BACKGROUND

Fetal growth restriction (FGR) increases risk for development of obesity and type 2 diabetes. Using a mouse model of FGR, we tested whether metabolic outcomes were exacerbated by high-fat diet challenge or associated with fecal microbial taxa.

METHODS

FGR was induced by maternal calorie restriction from gestation day 9 to 19. Control and FGR offspring were weaned to control (CON) or 45% fat diet (HFD). At age 16 weeks, offspring underwent intraperitoneal glucose tolerance testing, quantitative MRI body composition assessment, and energy balance studies. Total microbial DNA was used for amplification of the V4 variable region of the 16 S rRNA gene. Multivariable associations between groups and genera abundance were assessed using MaAsLin2.

RESULTS

Adult male FGR mice fed HFD gained weight faster and had impaired glucose tolerance compared to control HFD males, without differences among females. Irrespective of weaning diet, adult FGR males had depletion of Akkermansia, a mucin-residing genus known to be associated with weight gain and glucose handling. FGR females had diminished Bifidobacterium. Metabolic changes in FGR offspring were associated with persistent gut microbial changes.

CONCLUSION

FGR results in persistent gut microbial dysbiosis that may be a therapeutic target to improve metabolic outcomes.

IMPACT

Fetal growth restriction increases risk for metabolic syndrome later in life, especially if followed by rapid postnatal weight gain. We report that a high fat diet impacts weight and glucose handling in a mouse model of fetal growth restriction in a sexually dimorphic manner. Adult growth-restricted offspring had persistent changes in fecal microbial taxa known to be associated with weight, glucose homeostasis, and bile acid metabolism, particularly Akkermansia, Bilophilia and Bifidobacteria. The gut microbiome may represent a therapeutic target to improve long-term metabolic outcomes related to fetal growth restriction.

Perinatal exposures and adolescence overweight: The role of shared maternal-offspring pathways

BACKGROUND AND AIMS

Early life exposures affect offspring health across the life-course. We aimed to examine whether prevalent perinatal exposures and obstetric complications are independently associated with offspring overweight in adolescence. We then assessed whether shared maternal-offspring pathways drive the association of perinatal exposures with offspring overweight.

METHODS

Using data from the Jerusalem Perinatal Study birth cohort, two perinatal scores were constructed: obstetric complications (OC) and prevalent perinatal exposures (PPE) scores. PPE score, generated by principal component analysis, included three primary components. Logistic regressions were used to assess associations of scores with offspring overweight, with and without adjustment for maternal life-course survival.

RESULTS

OC and PPE scores were independently associated with offspring overweight (OROC = 1.15, 95%CI:1.07,1.25; ORPPE1- SEP and lifestyle = 0.85, 95%CI:0.79,0.91; ORPPE2- Maternal body size = 1.20, 95%CI: 1.13,1.28; ORPPE3-Fetal growth = 1.18, 95%CI:1.11,1.26). Maternal survival was associated with offspring overweight (OR = 1.38, 95%CI:1.08,1.76), yet introducing PPE score to the same model attenuated this association (OR = 1.16, 95%CI:0.90, 1.49). When OC score and maternal survival were included in the same model, their associations with offspring overweight remained unchanged.

CONCLUSIONS

Mother-offspring shared factors, captured by maternal life-course survival, underlie the effect of prevalent perinatal exposures on offspring overweight. However, the effect of obstetric complications was independent, highlighting the contribution of additional pathways.

Childhood circumstances, social mobility and the obesity transition: Evidence from South Africa

The distribution of obesity tends to shift from rich to poor individuals as countries develop, in a process of shifting sociodemographic patterns of obesity that has been called the 'obesity transition'. This change tends to happen with economic development, but little is known about the specific mechanisms that drive the change. We propose that improvements in childhood circumstances with economic development may be one of the drivers of the obesity transition. We explore whether the social gradient in body weight differs by childhood socioeconomic status (SES), proxied by the respondent's mother having Grade 12, using South Africa's nationally representative panel National Income Dynamics Study. In support of our hypothesis, we find that the social gradient in body weight is less positive for adults who had a high childhood SES, and already appears to have reversed among high-SES women who also had a high childhood SES. Upward social mobility over an individual's life course or across a single generation is associated with higher body weight compared to a stable high SES. But a high SES sustained in childhood and adulthood - or across more than one generation - may decrease adult obesity risk, and result in a reversal of the social gradient in body weight. Random effects within-between models show that the social gradient in body weight and its interaction with childhood SES are driven more by differences in income between individuals than by short-run changes in income within individuals, again suggesting that the obesity transition is driven by long-run changes rather than by very short-run changes. Our results are broadly robust to using several alternative measures of body weight, childhood SES and adult SES. Our results are consistent with the hypothesis that widespread improvements in childhood circumstances and nutrition with economic development may contribute to the shift to later stages of the obesity transition.

Conceptual and analytical approaches for modelling the developmental origins of inequality

In many species, individuals that experience harsh conditions during development have poor health and fitness outcomes in adulthood, compared with peers that do not. These early-life contributions to inequality are often attributed to two classes of evolutionary hypotheses: Developmental Constraints (DC) models, which focus on the deleterious effects of low-quality early-life environments, and Predictive Adaptive Response (PAR) hypotheses, which emphasize the costs individuals incur when they make incorrect predictions about conditions in adulthood. Testing these hypotheses empirically is difficult for conceptual and analytical reasons. Here, we help resolve some of these difficulties by providing mathematical definitions for DC, PAR (particularly focusing on 'external' PAR) and related concepts. We propose a novel, quadratic regression-based statistical test derived from these definitions. Our simulations show that this approach markedly improves the ability to discriminate between DC and PAR hypotheses relative to the status quo approach, which uses interaction effects. Simulated data indicate that the interaction effects approach often conflates PAR with DC, while the quadratic regression approach yields high sensitivity and specificity for detecting PAR. Our results highlight the value of linking verbal and visual models to a formal mathematical treatment for understanding the developmental origins of inequitable adult outcomes. This article is part of the theme issue 'Evolutionary ecology of inequality'.

Food Security and Nutrition as the Neglected Missing Links in Cultural Evolution: The Role of the Sociotype

Food security and nutrition were major drivers of cultural evolution by enabling sociotypic development and communal living after the Neolithic agricultural revolution some 12,000 years ago. The sociotype unites concepts from the sciences and the humanities; in concert with the genotype it determines an individual's phenotype (observable traits and behavior), and together they advance societal culture. As such, the sociotype relates to an individual's dynamic interactions with the surrounding social environment throughout life and comprises three domains: the Individual, Relationships, and Context. Nutrition affects each domain, respectively, by ensuring the following dimensions of food security: utilization (metabolic fuel and health); accessibility (physical and economic); and availability (the right to nutritious food for all citizens). The sociotype is influenced by multiple factors, including diet-gene interactions, allostasis, microbiota, oxytocin, and culturally through mate selection, family bonds, social communication, political ideologies, and values. Food security, sociotypes, and culture form a complex adaptive system to enable coping with the circumstances of life in health and disease, to achieve sustainable development, and to eradicate hunger. The current geopolitical unrest highlights the absolutely critical role of this system for global security, yet many challenges remain in implementing this paradigm for society. Therefore, sustainable food security must be considered a fundamental human right and responsibility for safeguarding the survival and progress of the sociotypes of humankind (Homo culturus) worldwide.

Exposure to Chinese Famine during Early Life Increases the Risk of Fracture during Adulthood

This study focused on identifying whether exposure to the Chinese Great Famine (1959–1961) in early life amplified the potential for fractures in adulthood. The survey was conducted using data from the 1997–2015 China Health and Nutrition Survey (CHNS)—5235 adults born between 1954 and 1964 were selected as the sample size. Fracture was defined based on self-report. Those born from 1962–1964 were treated as non-exposure group. Those with exposure to famine were divided into four subgroups: Fetal, early childhood, mid-childhood, and late childhood cohorts. The association between the groups and fracture was determined using Cox regression. In follow-up data (mean of 11 years), fractures were identified in 418 of the participants. The incidence of fracture was 8.7 in late childhood, 8.1 in mid-childhood, 8.3 in early childhood, 7.0 in fetal, and 5.4 in non-exposed cohorts per 1000 person-year. Compared with the non-exposed group, the famine-exposed groups had an increased risk of developing fracture in adulthood with hazard ratio (HR) and 95% CI of 1.29 (0.90–1.85), 1.48 (1.08–2.03), 1.45 (1.02–2.06), and 1.54 (1.08–2.20), respectively. The positive link of famine exposure to risk of fracture occurred primarily in those participants with a modern diet who lived in urban areas. In conclusion, the risk of fracture in Chinese adults is associated with famine exposure.