7 research outputs found

    The effect of chronic quercetin supplementation on bone health in postmenopausal women: A double-blind placebo-controlled investigation

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    Currently, there is limited research investigating the effects of quercetin on bone turnover and density. Therefore, this study aimed to examine the efficacy of 90-day quercetin supplementation on bone turnover, inflammation, body composition, and physical function in postmenopausal women. Thirty-four healthy postmenopausal women (59.2 ± 7.0 yrs, 80.7 ± 15.6 kg, 29.8 ± 6.1 kgâž±m2) participated in the double-blind placebo-controlled investigation. Participants were randomly assigned to one of two groups: 500 mg of Q or 500 mg of fiber (placebo; PLB). Data collected during the pre-and post-supplementation assessments included: bone turnover (osteocalcin, P1NP, CTX), inflammation markers (IL-6, TNF-alpha, CRP), body composition, dominant handgrip strength, and timed up and go test. Independent samples t-tests were used for between-group comparisons of baseline values and the percent change for each dependent variable. A significant difference in percent change for osteocalcin (Q: 20.5±25.7; PLB: 1.3±17.2; p=0.016; d=0.89), P1NP (Q: 28.9 (6.0–57.3); PLB: 4.6 (-7.6 – 8.5); p=0.030; d=0.64), and CTX (Q: 39.0 (-10.0 – 84.6); PLB: -7.74 (-28.9 – 18.5); p=0.023; d=0.91) was found between Q and PLB, with greater increases in Q. Changes in the inflammation markers IL-6 (Q: -17.6±24.1; PLB: 2.90±31.1; p=0.045; d=0.73) and TNF-alpha (Q: -4.9± (-15.3 – [-3.2]); PLB: 1.9 (-7.8 – 4.0); p=0.021; d=0.90) between the two groups were significant. No significant changes were found between groups for CRP, body composition, and physical function (p\u3e0.05). The data suggest that Q may improve bone health status in postmenopausal women through its ability to decrease pro-inflammatory mediators and increase turnover markers

    The Effect of Quercetin on Bone Turnover Markers, Inflammatory Markers, and Bone Mineral Density in Postmenopausal Women: A Double-Blind Placebo-Controlled Investigation

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    Maintaining optimal bone health prevents major bone disorders (e.g., osteoporosis) and prolongs longevity. Quercetin is a plant-based flavonoid that is suggested to have anti-inflammatory effects and may improve bone health. PURPOSE: To investigate the effects of quercetin supplementation over 90-days on prominent bone turnover markers (BTMs), inflammatory markers, bone mineral density (BMD), body composition, and physical functioning in postmenopausal women. METHODS: Thirty-three healthy, nonosteoporotic, postmenopausal women (59.2±7.0 years) participated in a double-blind, placebo-controlled investigation. Participants were randomized into one of two supplement groups: 1) 500 mg of quercetin (QUE) once daily or 2) 500 mg of methylcellulose (placebo; PLB) once daily. Pre- and post-testing visits included assessments of BTMs (i.e., osteocalcin [OC], procollagen type-I N-terminal propeptide [PINP], and type-I collagen cross-linked C-terminal telopeptide [CTX]), inflammatory markers (i.e., interleukin [IL]-6, tumor necrosis factor-alpha [TNF-a], and C-reactive protein [CRP]), BMD measurements, body composition measurements (i.e., body fat percentage), and physical function. RESULTS: The QUE group increased OC (p=0.016; d=0.89), PINP (p=0.030; d=0.64), and CTX (p=0.023; d=0.91) levels and decreased IL-6 (p=0.045; d=0.73) and TNF-a (p=0.021; d=0.90) levels compared to PLB. CRP (p=0.448; d=0.34), BMD, body composition, and physical function remained unchanged. CONCLUSION: The results indicate that QUE may maintain optimal bone health by mediating bone formation and decreasing pro-inflammatory cytokines

    Safety of short-term supplementation with methylliberine (DynamineÂź) alone and in combination with teacrineÂź in young adults

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    © 2020 by the authors. Licensee MDPI, Basel, Switzerland. Methylliberine (DynamineŸ; DYM) and theacrine (TeacrineŸ; TCR) are purine alkaloids purported to have similar neuro-energetic effects as caffeine. There are no published human safety data on DYM, and research on TCR is limited. The purpose of this study was to examine the effect of four weeks of DYM supplementation with and without TCR on cardiovascular function and blood biomarkers. One-hundred twenty-five men and women (mean age 23.0 yrs, height 169.7 cm, body mass 72.1 kg; n = 25/group) were randomly assigned to one of five groups: low-dose DYM (100 mg), high-dose DYM (150 mg), low-dose DYM with TCR (100 mg + 50 mg), high-dose DYM with TCR (150 mg + 25 mg), and placebo. Regardless of group and sex, significant main effects for time were noted for heart rate, systolic blood pressure, and QTc (p \u3c 0.001), high-density lipoproteins (p = 0.002), mean corpuscular hemoglobin (p = 0.018), basophils (p = 0.006), absolute eosinophils (p = 0.010), creatinine (p = 0.004), estimated glomerular filtration rate (p = 0.037), chloride (p = 0.030), carbon dioxide (p = 0.023), bilirubin (p = 0.027), and alanine aminotransferase (p = 0.043), among others. While small changes were found in some cardiovascular and blood biomarkers, no clinically significant changes occurred. This suggests that DYM alone or in combination with TCR consumed at the dosages used in this study does not appear to negatively affect markers of health over four weeks of continuous use

    Rate of Force Development as a Predictor of Mobility in Community-dwelling Older Adults

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    BACKGROUND AND PURPOSE: Rate of force development (RFD) is influential, and possibly more influential than other muscular performance parameters, for mobility in older adults. However, only a few studies have investigated this matter, and this has not been examined for the plantar flexors (PFs). The purpose of this study was to examine the contribution of PF RFD and other common tests of muscular performance to Up-and-Go (UG) performance and walking speed (WS) in older adults. METHODS: Twenty-six (19 females) healthy, community-dwelling older adults (73.7 ± 4.9 years) were recruited from a senior citizen center for this observational study. Handgrip strength, UG performance, as well as preferred and maximal WS were obtained. Time taken to complete 5-chair rises and the number of chair rises completed in 30 seconds were recorded. Rate of force development of the PFs was obtained during a rapid, bilateral calf raise performed on a force plate. Hierarchical multiple linear regression was used to identify significant predictors, after adjusting for physical activity level and body mass index, of mobility (ie, UG, preferred and maximal WS). RESULTS AND DISCUSSION: No muscular performance variables correlated with preferred WS. Rate of force development (adjusted R2 = 0.356; P = .008) and handgrip strength (adjusted R2 = 0.293; P = .026) were the only predictors of maximal WS and accounted for a 21.7% and 16.1% change in R2, respectively, after accounting for physical activity level and body mass index. Rate of force development was the only predictor of UG performance (adjusted R2 = 0.212; P = .006) and accounted for a 29.2% change in R2 after adjustment variables were applied. CONCLUSIONS: Compared to common assessments of muscular performance, such as handgrip strength and chair rise performance, PF RFD was a greater predictor of mobility in older adults. These findings, in conjunction with recent reports, indicate that the assessment of RFD likely complements strength testing, thereby enabling a more robust assessment of functional decline in older adults

    Microbiopsy Sampling for Examining Age-Related Differences in Skeletal Muscle Fiber Morphology and Composition

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    The increasingly popular microbiopsy is an appealing alternative to the more invasive Bergström biopsy given the challenges associated with harvesting skeletal muscle in older populations. Parameters of muscle fiber morphology and composition derived from the microbiopsy have not been compared between young and older adults. The purpose of this study was to examine muscle fiber morphology and composition in young (YM) and older (OM) males using the microbiopsy sampling technique. A secondary aim was to determine if specific strength is associated with serum levels of C-terminal agrin fragment [CAF; an indicator of neuromuscular junction (NMJ) degradation]. Thirty healthy, YM ( = 15, age = 20.7 ± 2.2 years) and OM ( = 15, age = 71.6 ± 3.9 years) underwent ultrasound imaging to determine whole-muscle cross-sectional area (CSA) of the vastus lateralis and rectus femoris as well as isometric and isokinetic (60°⋅s and 180°⋅s) peak torque testing of the knee extensors. Microbiopsy samples of the vastus lateralis were collected from 13 YM and 11 OM, and immunofluorescence was used to calculate CSA and proportion of type I and type II fibers. Peak torque was lower in OM at all velocities ( ≀ 0.001; = 1.39-1.86) but only lower at 180°⋅s ( = 0.003; = 1.23) when normalized to whole-muscle CSA. Whole-muscle CSA was smaller in OM ( = 0.001; = 1.34), but atrophy was not present at the single fiber level ( \u3e 0.05). Per individual, ∌900 fibers were analyzed, and type I fiber CSA was larger ( = 0.05; = 0.94) in OM which resulted in a smaller type II/I fiber CSA ratio ( = 0.015; = 0.95). CAF levels were not sensitive to age ( = 0.159; = 0.53) nor associated with specific strength or whole-muscle CSA in OM. The microbiopsy appears to be a viable alternative to the Bergström biopsy for histological analyses of skeletal muscle in older adults. NMJ integrity was not influential for age-related differences in specific strength in our healthy, non-sarcopenic older sample

    New insights into the genetic etiology of Alzheimer’s disease and related dementias

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    Characterization of the genetic landscape of Alzheimer’s disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/‘proxy’ AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE Δ4 allele

    New insights into the genetic etiology of Alzheimer’s disease and related dementias

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    Characterization of the genetic landscape of Alzheimer’s disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/‘proxy’ AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE Δ4 allele
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