A Dietary Assessment of Mid-Spectrum Chronic Kidney Disease

Diets of adult individuals with mid-spectrum (stages III and IV) Chronic Kidney Disease (CKD) remain understudied. The 2015-2020 Dietary Guidelines for Americans food patterns based on the Recommended Dietary Allowances (RDA) in concert with the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF KDOQI) guidelines are advised to individuals with CKD. Estimated glomerular filtration rate (eGFR) remains the best method for tracking CKD progression, yet relationships between self-reported dietary intake and eGFR are understudied. PURPOSE: To assess the self-reported dietary pattern in patients with stage III or IV CKD in contrast to the RDA and NKF KDOQI dietary guidelines and to identify correlates of eGFR. METHODS: Twenty participants with stage III or IV CKD [n = 6 male (M); n = 14 female (F)]; age 62.0 ± 9.9 years; weight 80.9 ± 16.2 kg; body fat 37.3 ± 8.5% of weight; eGFR 51.5 ± 6.82 mL/min/1.73m2) completed self-reported dietary assessments for an average of 5 days. Diet was assessed using the ESHA Food Processor Software, Version 11.1. Micro- and macronutrient analyses for males and females were compared to the RDA and NKF KDOQI guidelines to identify malnutrition. T-tests were used to test the difference in eGFR between genders and bivariate correlation analyses were used to identify correlates of eGFR, p-values were considered significant at the α = 0.05 level. RESULTS: On average, all subjects met the RDA and NKF KDOQI guidelines for caloric intake. Average consumption of saturated fat (F = 24.3 ± 10.8g, M = 34.1 ± 6.0g), sodium (F = 3780 ± 2510mg, M = 4210 ± 386mg) and protein (F = 65.0 ± 23.5g, M = 107.3 ± 27.3g) was higher than the recommendations while the average consumption of fiber (F = 13.6 ± 4.1g, M = 14.8 ± 7.3g), calcium (F = 573 ± 325mg, M = 720 ± 224mg), potassium (F = 240 ± 1800mg, M = 940 ± 492mg) and phosphorous (F = 628 ± 1320mg, M = 425 ± 314mg) was low. On average, males had a higher eGFR than females (t = -2.40, p = 0.03). Age, body fat percentage, weight, cholesterol, calcium intake, protein intake, and daily caloric intake were not found to be significantly correlated with eGFR. CONCLUSION: When compared to the RDA and NKF KDOQI guidelines, individuals with mid-spectrum CKD had poor nutritional quality. Female gender was correlated with reduced eGFR. Future interventions in individuals with mid-spectrum CKD should look to improve diet quality to align with clinical guidelines and prevent progression to end-stage renal disease

Wnt/β-Catenin and Androgen Receptor Signaling Increase Following High Load Resistance Exercise Without Elevations in Serum/Muscle Testosterone or Androgen Receptor Content

PURPOSE: The purpose of this study was 1) to determine the effect of single bouts of volume- and intensity-equated low (LL) and high load (HL) full-body resistance exercise (RE) on AR-DNA binding, serum/muscle testosterone and dihydrotestosterone, muscle androgen receptor (AR), and AR-DNA binding and 2) to determine the effect of RE on sarcoplasmic and nucleoplasmic β-catenin concentrations in order to determine their impact on mediating AR-DNA binding in the absence/presence of serum/muscle androgen and AR protein. METHODS: In a cross-over design, ten resistance-trained males completed volume- and intensity-equated LL and HL full-body RE. Blood and muscle samples were collected at pre-, 3h-, and 24h post-exercise. Separate 2x3 factorial ANOVAs with repeated measures and pairwise comparisons with a Bonferroni adjustment were used to analyze main effects. RESULTS: No significant differences were observed in muscle AR, testosterone, dihydrotestosterone, or serum total testosterone in either condition (p \u3e.05). Serum free testosterone was significantly decreased 3h post-exercise and remained significantly less than baseline 24h post-exercise in both conditions (p.05). Moreover, sarcoplasmic β-catenin was significantly greater in HL (p.05). CONCLUSION: Increases in AR-DNA binding in response to HL indicates AR signaling may be load-dependent. Furthermore, despite the lack of increase in serum and muscle androgens or AR content following HL RE, elevations in AR-DNA binding with elevated sarcoplasmic β-catenin suggests β-catenin may be facilitating this response

Impacts of Varying Blood Flow Restriction Cuff Size and Material on Arterial, Venous and Calf Muscle Pump-Mediated Blood Flow

Blood flow restriction (BFR) may become ineffective or potentially dangerous without sufficient standardization. The purpose of this investigation was therefore to (1) assess the viability of multiple sizes of a novel BFR cuff to determine arterial occlusion pressure (AOP) and (2) compare resting arterial, venous and calf muscle pump (cMP)-mediated blood flow between the aforementioned conditions and a commonly employed wide-rigid, tourniquet-style cuff. In randomized, counter-balanced, and crossover fashion, 20 apparently healthy males (18–40 years) donned a widely employed wide-rigid (WR) cuff, along with the largest (NE) and manufacturer-recommended sizes (NER) of a novel narrow-elastic cuff. Participants subsequently assessed AOP, as well as (at 80%AOP) arterial, venous, and venous cMP flow relative to baseline values via ultrasound. All analyses were performed at a significance level of p \u3c 0.05. Analyses revealed a significant condition effect for AOP (p \u3c 0.001; ηp2 = 0.907) whereby WR was significantly lower than both NE and NER; in addition, the latter two did not differ. Compared with baseline, there were no statistically significant differences between cuffs for either arterial or cMP-mediated blood flow. Unsurprisingly, no participants demonstrated venous blood flow at 80% AOP. These findings support the viability of a novel narrow-elastic BFR product, evidenced by consistent AOP acquisition and equivocal blood flow parameters

LGD-4033 and MK-677 Use Impacts Body Composition, Circulating Biomarkers, and Skeletal Muscle Androgenic Hormone and Receptor Content: A Case Report

LGD-4033, a selective androgen receptor modulator, and MK-677, a growth hormone secretagogue, are being used increasingly amongst recreationally active demographics. However, limited data exist describing their effects on health- and androgen-related biomarkers. The purpose of this case study was to determine changes in body composition and biomarkers during and after continued co-administration of LGD-4033 and MK-677. We also aimed to examine muscular strength and intramuscular androgen-associated biomarkers relative to non-users. A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks. Blood and body composition metrics were obtained pre-, on- and post-cycle. One-repetition maximum leg and bench press, in addition to intramuscular androgens and androgen receptor content, were analysed on-cycle. We observed pre- to on-cycle changes in body composition (body mass, +6.0%; total lean body mass, +3.1%; trunk lean body mass, +6.6%; appendicular lean body mass, +4.3%; total fat mass, +15.4%; trunk fat mass, +2.8%; and appendicular fat mass, +14.8%), bone (bone mineral content, −3.60%; area, −1.1%; and bone mineral density, −2.1%), serum lipid-associated biomarkers (cholesterol, +14.8%; triglycerides, +39.2%; low-density lipoprotein–cholesterol, +40.0%; and high-density lipoprotein–cholesterol, −36.4%), liver-associated biomarkers (aspartate aminotransferase, +95.8%; and alanine aminotransferase, +205.0%) and androgen-associated biomarkers (free testosterone, −85.7%; total testosterone, −62.3%; and sex hormone-binding globulin, −79.6%); however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein–cholesterol. Follicle-stimulating hormone was below clinical reference values on- (1.2 IU/L) and post-cycle (1.3 IU/L). Intramuscular androgen receptor (−44.6%), testosterone (+47.8%) and dihydrotestosterone (+34.4%), in addition to one-repetition maximum leg press and bench press (+39.2 and +32.0%, respectively), were different in the case subject compared with non-users. These data demonstrate that LGD-4033 and MK-677 increase several body composition parameters, whilst negatively impacting bone and several serum biomarkers. Given the sparsity of data in recreationally using demographics, further research is warranted to elucidate the acute and chronic physiological effects of these anabolic agents

Association between Total Body Composition and VO2max in Individuals with Mid-Spectrum Chronic Kidney Disease

Total body composition (TBC), a measure of body fat percentage (%BF), lean body mass (LBM), and bone mineral content (BMC), can be used as a predictor of cardiovascular fitness. Prior studies have established a relationship between TBC and VO2max in healthy individuals over 35 years of age. However, this relationship is poorly understood in chronic disease populations. PURPOSE: To assess the relationship between TBC and cardiovascular fitness in a clinical population of adults with mid-spectrum (stages G2, G3a, and G3b) chronic kidney disease (CKD). METHODS: A cross-sectional analysis was conducted among 24 subjects diagnosed with mid-spectrum CKD. Nine males and 15 females with an average age of 62.25±9.2 years and a glomerular filtration rate (GFR) of 54.38±9.04 ml/min/1.73m2 completed the study. Subjects completed a health screening, dual-energy x-ray absorptiometry (DEXA) scan, and underwent VO2max testing on a treadmill using a modified Bruce protocol. Normality tests, descriptive statistics, Pearson’s correlations, t-tests, and ANOVAs were conducted in SAS v.9.4. RESULTS: The average %BF was 36.28±8.47%, LBM was 117.16±31.32lbs., BMC was 2308.74±735.19g., and VO2max was 20.13±5.04ml/kg/min. VO2max was positively correlated with BMC and LBM (r=0.65, p=0.001 and r=0.75, p\u3c0.001, respectively) and negatively correlated with %BF (r= -0.80, p\u3c0.001). Individuals in later stages of CKD had lower LBM, BMC, and VO2max (p=0.017, p=0.001, and p=0.007, respectively), yet there was no association of CKD stage with %BF or age (p=0.210 and p=0.107). CONCLUSION: TBC was found to be significantly associated with cardiovascular fitness in the study sample. Higher BMD and LBM values were associated with higher VO2max whereas higher %BF was associated with a lower VO2max in individuals with mid-spectrum CKD. Progression of CKD stage was associated with lower LBM, BMC, and VO2max values, indicating a graded effect of CKD stage on cardiovascular fitness

The Effect of Fish Oil Supplementation on Resistance Training-induced Adaptations

Background: Resistance exercise training (RET) is a common and well-established method to induce hypertrophy and improvement in strength. Interestingly, fish oil supplementation (FOS) may aug-ment RET-induced adaptations. However, few studies have been conducted on young, healthy adults. Methods: A randomized, placebo-controlled design was used to determine the effect of FOS, a concentrated source of eicosapen-taenoic acid (EPA) and docosahexaenoic acid (DHA), compared to placebo (PL) on RET-induced adaptations following a 10-week RET program (3 days·week−1). Body composition was measured by dual- energy x-ray absorptiometry (LBM, fat mass [FM], percent body fat [%BF]) and strength was measured by 1-repetition maximum bar-bell back squat (1RMSQT) and bench press (1RMBP) at PRE (week 0) and POST (10 weeks). Supplement compliance was assessed via self-report and bottle collection every two weeks and via fatty acid dried blood spot collection at PRE and POST. An a priori α- level of 0.05 was used to determine statistical significance and Cohen’s d was used to quantify effect sizes (ES). Results: Twenty-one of 28 male and female participants (FOS, n = 10 [4 withdrawals]; PL, n = 11 [3 withdrawals]) completed the 10- week progressive RET program and PRE/POST measurements. After 10-weeks, blood EPA+DHA substantially increased in the FOS group (+109.7%, p\u3c .001) and did not change in the PL group (+1.3%, p = .938). Similar between-group changes in LBM (FOS: +3.4%, PL: +2.4%, p = .457), FM (FOS: −5.2%, PL: 0.0%, p = .092), and %BF (FOS: −5.9%, PL: −2.5%, p = .136) were observed, although, the between- group ES was considered large for FM (d = 0.84). Absolute and relative (kg·kg [body mass]−1) 1RMBP was significantly higher in the FOS group compared to PL (FOS: +17.7% vs. PL: +9.7%, p = .047; FOS: +17.6% vs. PL: +7.3%, p = .011; respectively), whereas absolute 1RMSQT was similar between conditions (FOS: +28.8% vs. PL: +20.5%, p = .191). Relative 1RMSQT was higher in the FOS group (FOS: +29.3% vs. PL: +17.9%, p = .045). Conclusions: When combined with RET, FOS improves absolute and relative 1RM upper-body and relative 1RM lower-body strength to a greater extent than that observed in the PL group of young, recreationally trained adults

Athletes can benefit from increased intake of EPA and DHA - evaluating the evidence

Fatty fish, which include mackerel, herring, salmon and sardines, and certain species of algae (e.g., Schizochytrium sp, Crytthecodiniumcohnii, and Phaeodactylumtricornutum) are the only naturally rich sources of the omega-3 polyunsaturated fatty acids (n-3 PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). EPA and DHA are the most biologically active members of the n-3 PUFA family. Limited dietary sources and fluctuating content of EPA and DHA in fish raise concerns about the status of EPA and DHA among athletes, as confirmed in a number of studies. The beneficial effects of EPA and DHA include controlling inflammation, supporting nervous system function, main-taining muscle mass after injury and improving training adaptation. Due to their inade-quate intake and beneficial health-promoting effects, athletes might wish to consider us-ing supplements that provide EPA and DHA. Here we provide an overview of the effects of EPA and DHA that are relevant to athletes and discuss the pros and cons of supple-ments as a source of EPA and DHA for athletes

A review and evaluation of study design considerations for omega-3 fatty acid supplementation trials in physically trained participants

Long chain omega-3 polyunsaturated fatty acid (LC n-3 PUFA) supplements, rich in eicosapentaenoic acid and/or docosahexaenoic acid, are increasingly being recommended within athletic institutions. The wide range of doses, durations and study designs implemented across trials make it difficult to provide clear recommendations. The importance of study design characteristics in LC n-3 PUFA trials has been detailed in cardiovascular disease research and these considerations may guide LC n-3 PUFA study design in healthy cohorts. This systematic review examined the quality of studies and study design considerations used in evaluating the evidence for LC n-3 PUFA improving performance in physically trained adults. SCOPUS, PubMed and Web of Science electronic databases were searched to identify studies that supplemented LC n-3 PUFA in physically trained participants. Forty six studies met inclusion. Most studies used a randomised control design. Risk of bias, assessed using the design-appropriate Cochrane Collaboration tool, revealed that studies had a predominant judgment of \u27some concerns\u27, \u27high risk\u27, or \u27moderate risk\u27 in randomised controlled, randomised crossover, or non-randomised studies, respectively. A custom 5-point quality assessment scale demonstrated that no study satisfied all recommendations for LC n-3 PUFA study design. This review has highlighted that the disparate range of study designs are likely contributing to the inconclusive state of outcomes pertaining LC n-3 PUFA as a potential ergogenic aid. Further research must adequately account for the specific LC n-3 PUFA study design considerations, underpinned by a clear hypothesis, in order to achieve evidence-based dose, duration and composition recommendations for physically trained individuals

Vitamin D3 Supplementation Alters Gut Microbiome Composition and Increases Stability in Healthy Individuals

Early onset colorectal cancer incidence has increased significantly. Evidence links serum 25(OH)D levels and the gut microbiome to colon carcinogenesis, with vitamin D pivotal in modulating the immune system and intestinal epithelial function. The effect of supplemental vitamin D3 on the gut microbiome in healthy adults is unclear. PURPOSE: Investigate the effect of a 12-week oral dose of 4000 IU vitamin D3 on acute and long-term gut microbiome changes in healthy adults. METHODS: Forty-three participants, aged 18-53, were randomized based on baseline serum 25(OH)D levels into treatment (n=21) and placebo groups (n=22). Fecal samples and dietary intake were collected at 15-time points during the 78-day study (daily collection for the first 14 days and one sample on day 78), and 16S rRNA sequencing was performed on samples (days 1,7,14, and 78). Bioinformatics tools (QIIME) and statistical methods (repeated measures ANOVA, PERMANOVA) were employed to assess microbial α-diversity, β-diversity, and microbiome stability. Participant characteristics were compared using student t-tests and chi-square. RESULTS: Vitamin D3 supplementation significantly increased serum 25(OH)D levels in the treatment group (baseline 39.94 ± 15.22 ng/mL, post-intervention 72.60 ± 27.87 ng/mL, pp=2.22e-16, Paired Wilcoxon Test). Microbial stability correlated positively with serum 25(OH)D levels up to a 60 ng/mL increase from baseline with no further changes beyond this threshold. The treatment group showed a significant increase in beneficial bacteria, including Bifidobacterium, Anaerostipes, and Eubacterium eligens, and a significant decrease in opportunistic pathogens, Bilophila wadsworthia, and Escherichia-Shigella post-intervention. CONCLUSION: Vitamin D3 supplementation significantly modifies the microbiome composition and influences microbiome stability in healthy adults. These data suggest that moderate dose Vitamin D3 supplementation may reduce the risk of colorectal cancer, in part, through improving the gut microbiome composition and stability

Resistance Exercise-Induced Increases in Muscle Myostatin mRNA and Protein Expression Are Subsequently Decreased in Circulation in the Presence of Increased Levels of the Extracellular Matrix Stabilizing Protein Decorin

Resistance exercise (RE) activates cell signaling pathways associated with myostatin. Decorin is located in the extracellular matrix (ECM) and can block the inhibitory effect of myostatin. This study sought to determine the impact of low-load (LL) and high-load (HL) RE on myostatin mRNA and protein expression along with changes in muscle decorin and circulating follistatin. Ten resistance-trained men performed a LL (50% 1RM) and HL (80% 1RM) RE session using the angled leg press and leg extension with load and volume equated. Venous blood samples and muscle biopsies were obtained prior to and at 3h and 24h following each RE session. Muscle myostatin mRNA expression was increased at 24h post-exercise (p = 0.032) in LL and at 3h (p = 0.044) and 24h (p = 0.003) post-exercise in HL. Muscle decorin was increased at 24h post-exercise (p \u3c 0.001) in LL and HL; however, muscle myostatin was increased at 24h post-exercise (p \u3c 0.001) only in HL. For muscle Smad 2/3, no significant differences were observed (p \u3e 0.05). Serum follistatin was increased and myostatin decreased at 24h post-exercise (p \u3c 0.001) in LL and HL. Muscle myostatin gene and protein expression increased in response to HL RE. However, serum myostatin was decreased in the presence of increases in decorin in muscle and follistatin in circulation. Therefore, our data suggest a possible mechanism may exist where decorin within the ECM is able to bind to, and decrease, myostatin that might otherwise enter the circulation for activin IIB (ACTIIB) receptor binding and subsequent canonical signaling through Smad 2/3