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Booth, S. L.

Publications and source records attributed to Booth, S. L..

5 recordsLinked to original sources

Commensal taxa in gut microbiota limit antibiotic resistance during extended oral antibiotic use

Certain bacterial infections, such as those involving prosthetics, can require antimicrobial therapy over months to years, potentially increasing the burden of antimicrobial resistance. Here we longitudinally track the antimicrobial resistome in mice during continuous antibiotic dosing over 21 months. The burden of antibiotic resistance genes (ARGs) initially increases, but, surprisingly, declines in later months, approaching levels observed in untreated animals. ARG burden is regulated by taxonomy and declines as ARG-harboring taxa that initially bloom are replaced by commensals. Furthermore, we find that the dynamics of antibiotic-induced ARG burden are influenced by age-related differences in microbial taxonomy and can be removed by fecal microbiota transplantation. We show that commensals may regulate the resistome by limiting the growth of ARG-harboring taxa, thereby providing antimicrobial expansion resistance.

microbiology↗

Estropausal gut microbiota transplant improves ovarian function in adult mice

Decline in ovarian function with age not only affects fertility but is also linked to a higher risk of age-related diseases in women (e.g. osteoporosis, dementia). Intriguingly, earlier menopause is linked to shorter lifespan; however, the underlying molecular mechanisms of ovarian aging are not well understood. Recent evidence suggests the gut microbiota may influence ovarian health. In this study, we characterized ovarian aging associated microbial profiles in mice and investigated the effect of the gut microbiome from young and estropausal female mice on ovarian health through fecal microbiota transplantation. We demonstrate that the ovarian transcriptome can be broadly remodeled after heterochronic microbiota transplantation, with a reduction in inflammation-related gene expression and trends consistent with transcriptional rejuvenation. Consistently, these mice exhibited enhanced ovarian health and increased fertility. Using metagenomics-based causal mediation analyses and serum untargeted metabolomics, we identified candidate microbial species and metabolites that may contribute to the observed effects of fecal microbiota transplantation. Our findings reveal a direct link between the gut microbiota and ovarian health.

physiology↗

Effects of long-term high dose aspartame on body mass, bone strength, femoral geometry, and microbiota composition in a young and aged cohort of male and female mice

BackgroundRecent reassessment of the safety of aspartame has prompted increased evaluation of its effect on the health of a range of tissues. The gut microbiome is altered by oral aspartame. One prior study suggested that changes in the microbiome caused by aspartame could influence the strength of bone in young skeletally developing mice. Here we ask how aspartame influences bone in mice of different age and sex. ObjectiveThe objective of this study was to determine the effect of aspartame on the bone strength and gut microbiota of young and aged mice. MethodsMale and female C57Bl/6J mice were untreated or treated with a high dose of aspartame in their drinking water from 1 month of age until 4 (young cohort; n = 80) or 22 months (aged cohort; n = 52). ResultsIn aged males, mice treated with aspartame had greater body mass, whole bone strength, and femoral geometry relative to untreated. Specifically, in aged males, aspartame led to 9% increase in body mass (p < 0.001), 22% increase in whole bone strength (p = 0.006), and 17% increase in section modulus (p < 0.001) relative to untreated mice. Aged males and females receiving aspartame had a different microbiota than untreated mice and a decreased abundance of Odoribacter. No differences in body mass, whole bone strength, or femoral geometry were associated with aspartame dosing in young males or young or aged females. ConclusionsAspartame treated aged males had greater whole bone strength and the effect appeared to be explained by greater body mass. Aspartame treatment did not alter whole bone strength in young males or young or aged females despite the aspartame having a similar effect on the microbiota of both aged males and females.

bioengineering↗

The Microbial Metagenome and Tissue Composition in Mice with Microbiome-Induced Reductions in Bone Strength

The genetic components of microbial species that inhabit the body are known collectively as the microbiome. Modifications to the microbiome have been implicated in disease processes throughout the body and have recently been shown to influence bone. Prior work has associated changes in the microbial taxonomy (phyla, class, species, etc.) in the gut with bone phenotypes but has provided limited information regarding mechanisms. With the goal of achieving a more mechanistic understanding of the effects of the microbiome on bone, we perform a metagenomic analysis of the gut microbiome that provides information on the functional capacity of the microbes (all microbial genes present) rather than only characterizing the microbial taxa. Male C57Bl/6 mice were subjected to disruption of the gut microbiota ({Delta}Microbiome) using oral antibiotics (from 4-16 weeks of age) or remained untreated (n=6-7/group). Disruption of the gut microbiome in this manner has been shown to lead to reductions in tissue mechanical properties and whole bone strength in adulthood with only minor changes in bone geometry and density. {Delta}Microbiome led to modifications in the abundance of microbial genes responsible for the synthesis of the bacterial cell wall and capsule; bacterially synthesized carbohydrates; and bacterially synthesized vitamins (B and K) (p <0.01). Follow up analysis focused on vitamin K, a factor that has previously been associated with bone health. The vitamin K content of the cecum, liver and kidneys was primarily microbe-derived forms of vitamin K (menaquinones) and was decreased by 32-66% in {Delta}Microbiome mice compared to untreated animals (p < 0.01). Bone mineral crystallinity was decreased (p=0.01) was decreased in {Delta}Microbiome mice (p < 0.001) and matrix carbonate-phosphoate ratio was increased. This study illustrates the use of metagenomic analysis to link the microbiome to bone phenotypes and implicates microbially synthesized vitamin-K as a regulator of bone matrix quality.

bioengineering↗

Large Meta-Analysis Provides Evidence For An Association Of Serum Vitamin D With Pulmonary Function

The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for the association of serum 25-hydroxyvitamin D [25(OH)D] and pulmonary function. We conducted the largest cross-sectional meta-analysis of the 25(OH)D- pulmonary function association to date, based on nine European ancestry (EA) cohorts (n=22,838) and five African ancestry (AA) cohorts (n=4,290) in the CHARGE Consortium. Data were analyzed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean (SD) serum 25(OH)D was 68 (29) nmol/L for EAs and 49 (21) nmol/L for AAs. For each 1 nmol/L higher 25(OH)D, forced expiratory volume in the first second (FEV1) was higher by 1.1 mL in EAs (95% CI: 0.9,1.3; P=2.5x10-21) and 1.8 mL (95% CI: 1.1,2.5; P=1.6x10-7) in Aas (Prace difference=0.06), and forced vital capacity (FVC) was higher by 1.3 mL in EAs (95% CI: 1.0,1.6; P=1.1x10-20) and 1.5 mL (95% CI: 0.8,2.3; P=1.2x10-4) in AAs (Prace difference=0.56). Among EAs, the 25(OH)D-FVC association was stronger in smokers: per 1nmol/L higher 25(OH)D, FVC was higher by 1.7 mL (95% CI: 1.1,2.3) for current smokers and 1.7 mL (95% CI: 1.2,2.1) for former smokers, compared to 0.8 mL (95% CI: 0.4,1.2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EAs, a stronger association was observed for smokers compared to never smokers, which supports the importance of vitamin D in vulnerable populations.\n\nCohort FundingThis work was supported by National Institutes of Health (NIH) grant number R21 HL125574 funded by the National Heart, Lung, and Blood Institute (NHLBI) and the NIH Office of Dietary Supplements (ODS) (co-Principal Investigators [co-PIs]: DBH and PAC). The corresponding author (PAC) had full access to the data for the meta-analysis, and had final responsibility for the decision to submit for publication. No funding source had any role in the analysis of the data, the writing of the manuscript, or the decision to submit it. This work was also supported in part by R01HL077612 (PI: RGB) and by the Intramural Research Program of the National Institutes of Health (NIH), National Institute of Environmental Health Sciences (ZO1 ES043012, PI: SJL). SJL is supported by the Intramural Research Program of NIH, National Institute of Environmental Health Sciences. Infrastructure for the CHARGE Consortium is supported in part by the NHLBI grant R01HL105756.\n\nThe Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study has been funded by NIH contracts N01-AG-1-2100 and 271201200022C, the National Institute on Aging (NIA) Intramural Research Program, Hjartavernd (the Icelandic Heart Association), and the Althingi (the Icelandic Parliament). The study is approved by the Icelandic National Bioethics Committee, VSN: 00-063. The researchers are indebted to the participants for their willingness to participate in the study.\n\nThe Atherosclerosis Risk in Communities Study is carried out as a collaborative study supported by NHLBI contracts HHSN268201100005C, HHSN268201100006C, HHSN268201100007C, HHSN268201100008C, HHSN268201100009C, HHSN268201100010C, HHSN268201100011C, and HHSN268201100012C. 25(OH)D measurements were conducted with the support of R01 HL103706 from the NHLBI and R01 HL103706-S1 from the NIH ODS. The authors thank the staff and participants of the ARIC study for their important contributions.\n\nThis Cardiovascular Health Study (CHS) research was supported by NHLBI contracts HHSN268201200036C, HHSN268200800007C, N01HC55222, N01HC85079, N01HC85080, N01HC85081, N01HC85082, N01HC85083, N01HC85086; and NHLBI grants U01HL080295, R01HL085251, R01HL087652, R01HL105756, R01HL103612, R01HL120393, and R01HL130114 with additional contribution from the National Institute of Neurological Disorders and Stroke (NINDS). Additional support was provided through R01AG023629 from NIA. A full list of principal CHS investigators and institutions can be found at CHS-NHLBI.org. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Vitamin D measurements were made possible by NHLBI (R01HL084443-01A2).\n\nThis work in Framingham Heart Study was supported by NHLBIs Framingham Heart Study contract (N01-HC-25195 and HHSN268201500001I). Vitamin D measurements in the Framingham study were made possible by NIA (R01 AG14759 to SLB.).\n\nThe Health Aging and Body Composition cohort study was supported by NIA contracts N01AG62101, N01AG2103, and N01AG62106, NIA grant R01-AG028050, NINR grant R01-NR012459, and in part by the Intramural Research Program of the NIA, NIH. This research was further supported by RC1AG035835, and the serum vitamin D assays were supported by R01AG029364.\n\nThe Multi-Ethnic Study of Atherosclerosis (MESA) study is conducted and supported by NHLBI in collaboration with MESA investigators. Support for MESA is provided by contracts HHSN268201500003I, N01-HC-95159, N01-HC-95160, N01-HC-95161, N01-HC-95162, N01-HC-95163, N01-HC-95164, N01-HC-95165, N01-HC-95166, N01-HC-95167, N01-HC-95168, and N01-HC-95169 from NHLBI, UL1-TR-000040, UL1-TR-001079, and UL1-TR-001881 from NCRR, and DK063491 from the NIDDK. The MESA Lung study was supported by grants R01 HL077612, RC1 HL100543 and R01 HL093081 from NHLBI. Support for the Mineral Metabolite dataset was provided by grant HL096875.\n\nThe Rotterdam Study is funded by Erasmus Medical Center and Erasmus University, Rotterdam, the Netherlands; the Organization for the Health Research and Development (ZonMw); the Research Institute for Diseases in the Elderly (RIDE); the Dutch Ministry of Education, Culture, and Science; the Dutch Ministry for Health, Welfare, and Sports; the European Commission (DG XII), and the Municipality of Rotterdam. LL was a postdoctoral fellow of the Research Foundation--Flanders (FWO) in Brussels, Belgium. Part of this work was supported by a FWO-grant G035014N. DSM Nutritional Products AG, Kaiseraugst, Switzerland, sponsored the Vitamin D serum analyses. The authors are grateful to the study participants, the staff from the Rotterdam Study, and the participating general practitioners and pharmacists.\n\nThe Coronary Artery Risk Development in Young Adults Study (CARDIA) is supported by contracts HHSN268201300025C, HHSN268201300026C, HHSN268201300027C, HHSN268201300028C, HHSN268201300029C, and HHSN268200900041C from the National Heart, Lung, and Blood Institute (NHLBI), the Intramural Research Program of the National Institute on Aging (NIA), and an intra-agency agreement between NIA and NHLBI (AG0005).\n\nAuthor DisclosureDr. Psaty serves on the DSMB of a clinical trial funded by the manufacturer (Zoll LifeCor) and on the Steering Committee of the Yale Open Data Access Project funded by Johnson & Johnson.\n\nAll other authors have no conflicts of interest. There is no commercial support or financial interest from the tobacco industry for the research presented.\n\nThe study sponsors were not involved in study design, data collection, data analysis, data interpretation, report writing, or decisions to submit the paper for publication. PAC and DBH had final responsibility for the decision to submit for publication.\n\nOnline Supporting MaterialSupplemental table, figures, and methods are available.\n\nAbbreviation Footnote

epidemiology↗