Association between low birth weight and elevated white blood cell count in adulthood within a Japanese population

The effect of low birth weight as an intrauterine exposure on the early onset of sarcopenia through possible molecular pathways

Sarcopenia, a musculoskeletal disease characterized by the progressive loss of skeletal muscle mass, strength, and physical performance, presents significant challenges to global public health due to its adverse effects on mobility, morbidity, mortality, and healthcare costs. This comprehensive review explores the intricate connections between sarcopenia and low birth weight (LBW), emphasizing the developmental origins of health and disease (DOHaD) hypothesis, inflammatory processes (inflammaging), mitochondrial dysfunction, circadian rhythm disruptions, epigenetic mechanisms, and genetic variations revealed through genome-wide studies (GWAS). A systematic search strategy was developed using PubMed to identify relevant English-language publications on sarcopenia, LBW, DOHaD, inflammaging, mitochondrial dysfunction, circadian disruption, epigenetic mechanisms, and GWAS. The publications consist of 46.2% reviews, 21.2% cohort studies, 4.8% systematic reviews, 1.9% cross-sectional studies, 13.4% animal studies, 4.8% genome-wide studies, 5.8% epigenome-wide studies, and 1.9% book chapters. The review identified key factors contributing to sarcopenia development, including the DOHaD hypothesis, LBW impact on muscle mass, inflammaging, mitochondrial dysfunction, the influence of clock genes, the role of epigenetic mechanisms, and genetic variations revealed through GWAS. The DOHaD theory suggests that LBW induces epigenetic alterations during foetal development, impacting long-term health outcomes, including the early onset of sarcopenia. LBW correlates with reduced muscle mass, grip strength, and lean body mass in adulthood, increasing the risk of sarcopenia. Chronic inflammation (inflammaging) and mitochondrial dysfunction contribute to sarcopenia, with LBW linked to increased oxidative stress and dysfunction. Disrupted circadian rhythms, regulated by genes such as BMAL1 and CLOCK, are associated with both LBW and sarcopenia, impacting lipid metabolism, muscle mass, and the ageing process. Early-life exposures, including LBW, induce epigenetic modifications like DNA methylation (DNAm) and histone changes, playing a pivotal role in sarcopenia development. Genome-wide studies have identified candidate genes and variants associated with lean body mass, muscle weakness, and sarcopenia, providing insights into genetic factors contributing to the disorder. LBW emerges as a potential early predictor of sarcopenia development, reflecting the impact of intrauterine exposures on long-term health outcomes. Understanding the complex interplay between LBW with inflammaging, mitochondrial dysfunction, circadian disruption, and epigenetic factors is essential for elucidating the pathogenesis of sarcopenia and developing targeted interventions. Future research on GWAS and the underlying mechanisms of LBW-associated sarcopenia is warranted to inform preventive strategies and improve public health outcomes.

The interrelationships of birthweight, inflammation and body composition in healthy adults

BACKGROUND

Lower birthweight is associated with an increased risk of cardiovascular diseases and diabetes. We hypothesized that inflammation and body fat may be potential mediators for these inverse relationships.

MATERIALS AND METHODS

Healthy adults aged 25-41 years were enrolled in a prospective population-based cohort study in the Principality of Liechtenstein. Main exclusion criteria were diabetes, overt cardiovascular disease or a body mass index > 35 kg/m(2) . Birthweight was self-reported by the study participants. White blood cell (WBC) count and high-sensitivity C-reactive protein (hs-CRP) levels were assayed from fresh blood samples. Body composition was determined by bioelectrical impedance analysis. Multivariable linear regression models were constructed to assess the relationships between birthweight, inflammation and body composition.

RESULTS

Our sample consisted of 1774 participants (53·4% females) with a median age of 37 years. Median birthweight was 3355 g. In multivariable models, we found an inverse relationship of birthweight with hs-CRP levels (β -0·010 (95% CI -0·02; -0·002), P = 0·01) and WBC count (β -0·002 (95% CI -0·004; -0·0002), P = 0·03). Additional adjustment for body fat mass attenuated these relationships (β -0·008 (95% CI -0·02; 0·0003), P = 0·06 for hs-CRP levels and (β -0·002 (95% CI -0·004; 0·0006), P = 0·16 for WBC count. Body fat mass itself was strongly associated with birthweight (β -0·06 (95% CI -0·10; -0·03), P < 0·0001).

CONCLUSION

Birthweight is inversely associated with inflammation in adulthood. This relationship may be mediated by an elevated body fat mass among individuals with lower birthweight.

High-density lipoprotein-cholesterol trajectory pattern, associated lifestyle and biochemical factors among Taiwanese

BACKGROUND

Little is known about high-density lipoprotein-cholesterol (HDL-C) trajectory patterns among ethnic Chinese in Taiwan, or the effects of lifestyle and biochemical measurements on these trajectory patterns.

METHODS AND RESULTS

This longitudinal study was based on 330 adult participants who underwent biochemical measurements annually from 2003 to 2006. As time progressed, HDL-C increased significantly; women had a consistently higher value (10 mg/dl) than men. An increase of 1 kg/m(2) in body mass index was associated with -1.00 +/-0.25 mg/dl HDL-C for women (P=0.0001) and -0.78 +/-0.11 mg/dl for men (P<0.0001). Current smoking was inversely associated with HDL-C in men only. Systolic blood pressure and exercise frequency were positively associated with HDL-C in men only. Compared with non-smokers, participants who smoked had a lower HDL-C level of -8.42 +/-4.90 mg/dl in women (P=0.09) and -3.60 +/-0.94 mg/dl in men (P=0.0001). In contrast, a 1-h increase in exercise frequency every week was related to an increased HDL-C level of 0.38 +/-0.28 mg/dl for women (P=0.18) and 0.53 +/-0.14 mg/dl for men (P=0.0001).

CONCLUSIONS

An increase in HDL-C was shown over a 4-year period and gender-specific lifestyle factors were associated with HDL-C concentration among ethnic Chinese in Taiwan.