Plasminogen Activator Inhibitor-1 is Regulated Through Dietary Fat Intake and Heritability: Studies in Twins

Diet Quality and Epigenetic Aging in the Women's Health Initiative

BACKGROUND

Higher diet quality scores are associated with a lower risk for many chronic diseases and all-cause mortality; however, it is unclear if diet quality is associated with aging biology.

OBJECTIVE

This study aimed to examine the association between diet quality and a measure of biological aging known as epigenetic aging.

DESIGN

A cross-sectional data analysis was used to examine the association between three diet quality scores based on self-reported food frequency questionnaire data and five measures of epigenetic aging based on DNA methylation (DNAm) data from peripheral blood.

PARTICIPANTS/SETTING

This study included 4,500 postmenopausal women recruited from multiple sites across the United States (1993-98), aged 50 to 79 years, with food frequency questionnaire and DNAm data available from the Women's Health Initiative baseline visit.

MAIN OUTCOME MEASURES

Five established epigenetic aging measures were generated from HumanMethylation450 Beadchip DNAm data, including AgeAccelHannum, AgeAccelHorvath, AgeAccelPheno, AgeAccelGrim, and DunedinPACE.

STATISTICAL ANALYSES PERFORMED

Linear mixed models were used to test for associations between three diet quality scores (Healthy Eating Index, Dietary Approaches to Stop Hypertension, and alternate Mediterranean diet scores) and epigenetic aging measures, adjusted for age, race and ethnicity, education, tobacco smoking, physical activity, Women's Health Initiative substudy from which DNAm data were obtained, and DNAm-based estimates of leukocyte proportions.

RESULTS

Healthy Eating Index, Dietary Approaches to Stop Hypertension, and alternate Mediterranean diet scores were all inversely associated with AgeAccelPheno, AgeAccelGrim, and DunedinPACE (P < 0.05), with the largest effects with DunedinPACE. A one standard deviation increment in diet quality scores was associated with a decrement (β ± SE) in DunedinPACE z score of -0.097 ± 0.014 (P = 9.70 x 10-13) for Healthy Eating Index, -0.107 ± 0.014 (P = 1.53 x 10-14) for Dietary Approaches to Stop Hypertension, and -0.068 ± 0.013 (P = 2.31 x 10-07) for the alternate Mediterranean diet.

CONCLUSIONS

In postmenopausal women, diet quality scores were inversely associated with DNAm-based measures of biological aging, particularly DunedinPACE.

Supplementing L-Citrulline Can Extend Lifespan in C. elegans and Attenuate the Development of Aging-Related Impairments of Glucose Tolerance and Intestinal Barrier in Mice

L-Citrulline (L-Cit) is discussed to possess a protective effect on intestinal barrier dysfunction but also to diminish aging-associated degenerative processes. Here, the effects of L-Cit on lifespan were assessed in C. elegans, while the effects of L-Cit on aging-associated decline were determined in C57BL/6J mice. For lifespan analysis, C. elegans were treated with ±5 mM L-Cit. Twelve-month-old male C57BL/6J mice (n = 8-10/group) fed a standard chow diet received drinking water ± 2.5 g/kg/d L-Cit or 5 g/kg/d hydrolyzed soy protein (Iso-N-control) for 16 or 32 weeks. Additionally, 4-month-old C57BL/6J mice were treated accordingly for 8 weeks. Markers of senescence, glucose tolerance, intestinal barrier function, and intestinal microbiota composition were analyzed in mice. L-Cit treatment significantly extended the lifespan of C. elegans. The significant increase in markers of senescence and signs of impaired glucose tolerance found in 16- and 20-month-old control mice was attenuated in L-Cit-fed mice, which was associated with protection from intestinal barrier dysfunction and a decrease in NO2- levels in the small intestine, while no marked differences in intestinal microbiota composition were found when comparing age-matched groups. Our results suggest that pharmacological doses of L-Cit may have beneficial effects on lifespan in C. elegans and aging-associated decline in mice.

The mediatory role of inflammatory markers on the relationship between dietary energy density and body composition among obese and overweight adult women: A cross-sectional study

AIMS

Energy density (ED) is known to influence body composition (BC). Indeed, consumption of high ED foods can increase body fat mass (BFM) and inflammatory markers. We sought to assess the mediatory role of high-sensitive-C-reactive protein (hs-CRP), transforming growth factor-β (TGF-beta), and plasminogen activator inhibitor-1 (PAI-1) on the relationship between ED and BC in women with overweight/obesity.

METHODS

This was a cross-sectional study consisting of 391 women. Body composition (Bioelectrical Impedance Analysis) and a food frequency questionnaire (FFQ) was used to assess the BC and food intake of individuals. Blood samples and serum level of hs-CRP, PAI-1, and TGF-β were collected. ED per one gram of foods was calculated and divided to quartiles. Linear logistic regression was used to investigate the association between BC across quartiles of ED intake.

RESULTS

Total body water (TBW), fat free mass (FFM), visceral fat area (VFA), and fat free mass index (FFMI) appeared to be mediated by hs-CRP across ED quartiles. TBW, FFM with PAI-1, bone mineral content (BMC) with PAI-1 and TGF-beta, and skeletal lean mass (SLM) were inversely associated with hs-CRP, respectively. Fat trunk, TBW, BFM, FFM, SLM, waist circumference (WC), FFMI, and FMI were positively mediated by TGF-beta with increasing ED food intakes. Fat trunk, BFM, SLM, WC, FFMI and FMI were positively mediated by PAI-1.

CONCLUSIONS

Most BC subcategories were positively associated with higher ED intake, mediated by increasing serum levels of PAI-1 and TGF-beta. Moreover, higher serum hs-CRP levels may be related to body fat and water alteration concomitant to a higher ED intake.