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1.
J Int Soc Sports Nutr ; 20(1): 2243252, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37551682

ABSTRACT

INTRODUCTION: Chronic pain affects 19% of adults in the United States, with increasing prevalence in active and aging populations. Pain can limit physical activity and activities of daily living (ADLs), resulting in declined mental and social health. Nutritional interventions for pain currently target inflammation or joint health, but few influence both. Collagen, the most abundant protein in the human body and constituent of the extra cellular matrix, is such a nutraceutical. While there have been reports of reductions in pain with short-term collagen peptide (CP) supplementation, there are no long-term studies specifically in healthy middle-aged active adults. PURPOSE: To determine the effects of daily CP consumption over 3, 6, and 9 months on survey measures of pain, function, and physical and mental health using The Knee Injury & Osteoarthritis Outcomes Score (KOOS) and Veterans Rand 12 (VR-12) in middle-aged active adults. METHODS: This study was a double-blind randomized control trial with three treatment groups (Placebo, 10 g/d CP, and 20 g/d CP). RESULTS: Improvements in ADLs (p = .031, ηp2 = .096) and pain (p = .037, ηp2 = .164) were observed with 10 g/d CP over 6 months, although pain only improved in high frequency exercisers (>180 min/week). Additionally, VR-12 mental component scores (MCS) improved with 10 g/d of CP over 3-9 months (p = .017, ηp2 = .309), while physical component scores (PCS) improved with 20 g/d of CP over 3-9 months, but only in females (p = .013, ηp2= .582). CONCLUSION: These findings suggest 10 to 20 g/d of CP supplementation over 6 to 9 months may improve ADLs, pain, MCS, and PCS in middle-aged active adults.


Subject(s)
Activities of Daily Living , Osteoarthritis, Knee , Middle Aged , Female , Humans , Adult , Osteoarthritis, Knee/drug therapy , Pain/drug therapy , Peptides , Dietary Supplements , Collagen/therapeutic use , Treatment Outcome
2.
Curr Opin Clin Nutr Metab Care ; 25(6): 401-406, 2022 11 01.
Article in English | MEDLINE | ID: mdl-36044324

ABSTRACT

PURPOSE OF REVIEW: Connective tissue injuries are prevalent in active and aging populations, leading to chronic pain and decreased function. Turnover of this tissue is not well understood, especially as it relates to aging and injury. Supplementation of collagen peptides has been shown to improve connective tissue recovery and pain through increased collagen production. RECENT FINDINGS: Collagen peptide supplementation improves pain and function, and upregulates metabolic pathways associated with muscle and tendon growth. Literature from the past 12-18 months supports that these pathways are also involved with increased synthesis and degradation of collagen and other elements of the extracellular matrix. Improvements in body composition and strength have been noted with collagen peptide supplementation when paired with resistance training. Collagen peptide supplements are hydrolyzed into small peptides, termed bioactive peptides, and individual amino acids. These bioactive peptides are associated with the benefits observed with collagen peptide supplementation and may play a critical role in the collagen turnover. SUMMARY: Collagen peptide supplementation has been shown to promote recovery, decrease pain, and improve strength and body composition when paired with resistance training. These benefits may be attributed to bioactive peptides in collagen peptide supplements. Additional research is warranted to examine the specific effects of these bioactive peptides.


Subject(s)
Collagen , Peptides , Amino Acids , Collagen/chemistry , Dietary Supplements , Humans , Pain , Peptides/pharmacology , Peptides/therapeutic use
3.
Nutrients ; 14(2)2022 Jan 10.
Article in English | MEDLINE | ID: mdl-35057457

ABSTRACT

Osteoporosis is a major health concern in aging populations, where 54% of the U.S. population aged 50 and older have low bone mineral density (BMD). Increases in inflammation and oxidative stress play a major role in the development of osteoporosis. Men are at a greater risk of mortality due to osteoporosis-related fractures. Our earlier findings in rodent male and female models of osteoporosis, as well as postmenopausal women strongly suggest the efficacy of prunes (dried plum) in reducing inflammation and preventing/reversing bone loss. The objective of this study was to examine the effects of two doses of prunes, daily, on biomarkers of inflammation and bone metabolism in men with some degree of bone loss (BMD; t-score between -0.1 and -2.5 SD), for three months. Thirty-five men between the ages of 55 and 80 years were randomized into one of three groups: 100 g prunes, 50 g prunes, or control. Consumption of 100 g prunes led to a significant decrease in serum osteocalcin (p < 0.001). Consumption of 50 g prunes led to significant decreases in serum osteoprotegerin (OPG) (p = 0.003) and serum osteocalcin (p = 0.040), and an increase in the OPG:RANKL ratio (p = 0.041). Regular consumption of either 100 g or 50 g prunes for three months may positively affect bone turnover.


Subject(s)
Bone Density/physiology , Bone and Bones/metabolism , Osteoporosis/blood , Phytotherapy/methods , Prunus domestica , Aged , Aged, 80 and over , Biomarkers/blood , Body Composition , Bone Remodeling , Exercise , Humans , Inflammation/blood , Inflammation/prevention & control , Lumbar Vertebrae/diagnostic imaging , Male , Middle Aged , Osteocalcin/blood , Osteoporosis/prevention & control , Osteoporotic Fractures/prevention & control , Osteoprotegerin/blood , RANK Ligand/blood
4.
Nutrients ; 13(3)2021 Mar 05.
Article in English | MEDLINE | ID: mdl-33807747

ABSTRACT

Creatine is an organic compound, consumed exogenously in the diet and synthesized endogenously via an intricate inter-organ process. Functioning in conjunction with creatine kinase, creatine has long been known for its pivotal role in cellular energy provision and energy shuttling. In addition to the abundance of evidence supporting the ergogenic benefits of creatine supplementation, recent evidence suggests a far broader application for creatine within various myopathies, neurodegenerative diseases, and other pathologies. Furthermore, creatine has been found to exhibit non-energy related properties, contributing as a possible direct and in-direct antioxidant and eliciting anti-inflammatory effects. In spite of the new clinical success of supplemental creatine, there is little scientific insight into the potential effects of creatine on cardiovascular disease (CVD), the leading cause of mortality. Taking into consideration the non-energy related actions of creatine, highlighted in this review, it can be speculated that creatine supplementation may serve as an adjuvant therapy for the management of vascular health in at-risk populations. This review, therefore, not only aims to summarize the current literature surrounding creatine and vascular health, but to also shed light onto the potential mechanisms in which creatine may be able to serve as a beneficial supplement capable of imparting vascular-protective properties and promoting vascular health.


Subject(s)
Cardiovascular Agents/pharmacology , Cardiovascular Diseases/drug therapy , Cardiovascular Physiological Phenomena/drug effects , Creatine/pharmacology , Dietary Supplements , Heart Disease Risk Factors , Humans
5.
Nutrients ; 12(9)2020 Sep 16.
Article in English | MEDLINE | ID: mdl-32947909

ABSTRACT

Creatine is a naturally occurring compound, functioning in conjunction with creatine kinase to play a quintessential role in both cellular energy provision and intracellular energy shuttling. An extensive body of literature solidifies the plethora of ergogenic benefits gained following dietary creatine supplementation; however, recent findings have further indicated a potential therapeutic role for creatine in several pathologies such as myopathies, neurodegenerative disorders, metabolic disturbances, chronic kidney disease and inflammatory diseases. Furthermore, creatine has been found to exhibit non-energy-related properties, such as serving as a potential antioxidant and anti-inflammatory. Despite the therapeutic success of creatine supplementation in varying clinical populations, there is scarce information regarding the potential application of creatine for combatting the current leading cause of mortality, cardiovascular disease (CVD). Taking into consideration the broad ergogenic and non-energy-related actions of creatine, we hypothesize that creatine supplementation may be a potential therapeutic strategy for improving vascular health in at-risk populations such as older adults or those with CVD. With an extensive literature search, we have found only four clinical studies that have investigated the direct effect of creatine on vascular health and function. In this review, we aim to give a short background on the pleiotropic applications of creatine, and to then summarize the current literature surrounding creatine and vascular health. Furthermore, we discuss the varying mechanisms by which creatine could benefit vascular health and function, such as the impact of creatine supplementation upon inflammation and oxidative stress.


Subject(s)
Creatine/pharmacology , Dietary Supplements , Vascular Diseases/prevention & control , Creatine/therapeutic use , Humans
6.
Nutrients ; 12(7)2020 Jul 10.
Article in English | MEDLINE | ID: mdl-32664290

ABSTRACT

Pre-sleep whey protein intake has been shown to improve overnight muscle protein synthesis, muscle size and strength, and muscle recovery. Despite a growing interest in alternative protein sources, such as plant-based protein, there is no evidence regarding the efficacy of plant-based proteins consumed pre-sleep. Therefore, we aimed to compare whey vs. plant-based pre-sleep protein dietary supplementation on muscle recovery in middle-aged men. Twenty-seven recreationally active, middle-aged men performed 5 sets of 15 repetitions of maximal eccentric voluntary contractions (ECC) for the knee extensors (ext) and flexors (flex), respectively, in the morning. Participants consumed 40 g of either whey hydrolysate (WH, n = 9), whey isolate (WI, n = 6), rice and pea combination (RP, n = 6), or placebo (PL, n = 6) 30 min pre-sleep on the day of ECC and the following two nights. Catered meals (15% PRO, 55% CHO, 30% Fat) were provided to participants for 5 days to standardize nutrition. Plasma creatine kinase (CK), interleukin-6 (IL-6), and interleukin-10 (IL-10) were measured at pre, immediately post (+0), +4, +6, +24, +48, and +72 h post-ECC. Isometric (ISOM) and isokinetic (ISOK) maximal voluntary contraction force were measured at pre, immediately post (+0), +24, +48, and +72 h post-ECC. Muscle soreness, thigh circumference, and HOMA-IR were measured at pre, +24, +48, and +72 h post-ECC. CK was increased at +4 h post-ECC, remained elevated at all time points compared to baseline (p < 0.001), and was significantly greater at +72 h compared to all other time points (p < 0.001). IL-6 was increased at +6 h (p = 0.002) with no other time differing from baseline. ISOMext was reduced after ECC (p = 0.001) and remained reduced until returning to baseline at +72 h. ISOMflex, ISOKext, and ISOKflex were reduced after ECC and remained reduced at +72 h (p < 0.001). Muscle soreness increased post-ECC (p < 0.001) and did not return to baseline. Thigh circumference (p = 0.456) and HOMA-IR (p = 0.396) did not change post-ECC. There were no significant differences between groups for any outcome measure. These data suggest that middle-aged men consuming 1.08 ± 0.02 g/kg/day PRO did not recover from damaging eccentric exercise at +72 h and that pre-sleep protein ingestion, regardless of protein source, did not aid in muscle recovery when damaging eccentric exercise was performed in the morning.


Subject(s)
Exercise , Muscle, Skeletal/drug effects , Plant Proteins, Dietary/administration & dosage , Sleep , Whey Proteins/administration & dosage , Adult , Creatine Kinase/blood , Dietary Supplements , Humans , Isometric Contraction , Male , Middle Aged , Muscle Proteins/metabolism , Muscle Strength , Muscle, Skeletal/metabolism , Myalgia/epidemiology , Oryza/metabolism , Pea Proteins/administration & dosage
7.
Nutrients ; 12(2)2020 Feb 22.
Article in English | MEDLINE | ID: mdl-32098418

ABSTRACT

Vitamin D is known to elicit a vasoprotective effect, while vitamin D deficiency is a risk factor for endothelial dysfunction (ED). ED is characterized by reduced bioavailability of a potent endothelium-dependent vasodilator, nitric oxide (NO), and is an early event in the development of atherosclerosis. In endothelial cells, vitamin D regulates NO synthesis by mediating the activity of the endothelial NO synthase (eNOS). Under pathogenic conditions, the oxidative stress caused by excessive production of reactive oxygen species (ROS) facilitates NO degradation and suppresses NO synthesis, consequently reducing NO bioavailability. Vitamin D, however, counteracts the activity of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase which produces ROS, and improves antioxidant capacity by enhancing the activity of antioxidative enzymes such as superoxide dismutase. In addition to ROS, proinflammatory mediators such as TNF-α and IL-6 are risk factors for ED, restraining NO and eNOS bioactivity and upregulating the expression of various atherosclerotic factors through the NF-κB pathway. These proinflammatory activities are inhibited by vitamin D by suppressing NF-κB signaling and production of proinflammatory cytokines. In this review, we discuss the diverse activities of vitamin D in regulating NO bioavailability and endothelial function.


Subject(s)
Atherosclerosis/prevention & control , Endothelium, Vascular/physiopathology , Vitamin D Deficiency/complications , Vitamin D/administration & dosage , Atherosclerosis/blood , Atherosclerosis/etiology , Atherosclerosis/physiopathology , Clinical Trials as Topic , Dietary Supplements , Endothelium, Vascular/drug effects , Humans , NADPH Oxidases/metabolism , Nitric Oxide/biosynthesis , Nitric Oxide Synthase Type III/metabolism , Oxidative Stress/drug effects , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Superoxide Dismutase/metabolism , Treatment Outcome , Vitamin D/blood , Vitamin D/metabolism , Vitamin D Deficiency/blood , Vitamin D Deficiency/diet therapy , Vitamin D Deficiency/physiopathology
8.
Arch Phys Med Rehabil ; 99(11): 2151-2159, 2018 11.
Article in English | MEDLINE | ID: mdl-30092205

ABSTRACT

OBJECTIVE: To investigate changes in nutritive blood flow as well as interstitial glucose and lactate within an active myofascial trigger point (MTrP) following massage. DESIGN: Randomized, placebo-controlled trial. SETTING: Subjects were recruited from the general population; procedures were conducted at a research center affiliated with a university hospital. PARTICIPANTS: Adults (N=25) (18-49y old) with episodic or chronic tension-type headache and an active MTrP in the upper trapezius muscle. INTERVENTIONS: Subjects were randomized to receive a single trigger point (TrP) release massage or sham ultrasound (US) treatment at an active MTrP in the upper trapezius muscle. Microdialysis was used to continuously sample interstitial fluid from the MTrP before, during, and for 60 minutes following intervention. MAIN OUTCOME MEASURES: The primary outcome measure was nutritive blood flow within the MTrP as measured by microdialysis ethanol clearance; secondary measures included dialysate glucose, dialysate lactate, and subject discomfort with the procedures. Pressure-pain threshold (PPT) was determined to assess treatment effectiveness. RESULTS: There was no treatment effect of TrP release massage on nutritive blood flow (P=.663) or dialysate glucose (P=.766). The interaction for lactate was significant indicating that dialysate lactate increased for TrP release massage vs sham US (P=.04); maximum lactate increase over baseline was observed at 60 minutes after TrP release massage (P=.007, 0.128 µM, 95% confidence interval 0.045-0.212). Pain evoked by probe placement into an active MTrP was low. An interaction effect on PPT was significant (P=.005). CONCLUSION: TrP release massage of an active MTrP affected anaerobic metabolism as represented by an increase in dialysate lactate without change in nutritive blood flow or dialysate glucose. The lack of a treatment effect on blood flow is discussed.


Subject(s)
Glucose/metabolism , Headache Disorders/therapy , Lactic Acid/metabolism , Massage/methods , Regional Blood Flow/physiology , Tension-Type Headache/therapy , Trigger Points/physiopathology , Adolescent , Adult , Extracellular Fluid/metabolism , Female , Headache Disorders/physiopathology , Humans , Male , Middle Aged , Pain Threshold/physiology , Superficial Back Muscles/physiopathology , Tension-Type Headache/physiopathology , Treatment Outcome , Young Adult
9.
J Strength Cond Res ; 29(12): 3453-65, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26595135

ABSTRACT

Although multi-ingredient performance supplements (MIPS) have increased in popularity because of their array of ergogenic ingredients, their efficacy and safety remain in question. The objective of this study was to determine the impact of supplementation with T+ (SUP; Onnit Labs, Austin, TX, USA), an MIPS containing long jack root, beta-alanine, and branched-chain amino acids, and other proprietary blends, on strength, body composition, and hormones in young resistance-trained men. Subjects were randomized to consume either T+ (SUP; n = 14; age, 21 ± 3 years; body fat, 18.3 ± 4.7%) or an isocaloric placebo (PL; n = 13; age, 21 ± 3 years; body fat, 21.5 ± 6.2%) for 4 weeks. Both groups underwent a progressive, 4-week high-intensity resistance training protocol. Before and after the training protocol, mood state, body composition, blood hormones (also collected at midpoint), and maximal strength were measured. SUP had significantly greater increases in bench press (SUP, 102 ± 16 kg to 108 ± 16 kg vs. PL, 96 ± 22 kg to 101 ± 22 kg; p < 0.001) and total weight lifted (SUP, 379 ± 59 kg to 413 ± 60 kg vs. PL, 376 ± 70 kg to 400 ± 75 kg; p < 0.001) compared with PL. Additionally, deadlift strength relative to total body mass (calculated as weight lifted/body mass; kg:kg) (2.08 ± 0.18 to 2.23 ± 0.16; p = 0.036) and lean mass (2.55 ± 0.19 to 2.72 ± 0.16; p = 0.021) increased significantly in SUP but not PL (2.02 ± 0.30 to 2.15 ± 0.36 and 2.56 ± 0.31 to 2.70 ± 0.36, respectively). No other significant differences were detected between groups for the remaining variables. Supplementing with SUP enhanced resistance training adaptations independent of hormonal status, and thus SUP use may warrant inclusion into peri-workout nutrition regimens. This study was registered with clinicaltrials.gov (identifier: NCT01971723).


Subject(s)
Body Composition/drug effects , Dietary Supplements , Hormones/blood , Muscle Strength/drug effects , Resistance Training , Adaptation, Physiological/drug effects , Adolescent , Amino Acids, Branched-Chain/pharmacology , Dietary Supplements/adverse effects , Eurycoma , Humans , Male , Plant Preparations/pharmacology , Plant Roots , Weight Lifting/physiology , Young Adult , beta-Alanine/pharmacology
10.
Arch Phys Med Rehabil ; 94(1): 196-200, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22975226

ABSTRACT

OBJECTIVE: To demonstrate proof-of-principle measurement for physiologic change within an active myofascial trigger point (MTrP) undergoing trigger point release (ischemic compression). DESIGN: Interstitial fluid was sampled continuously at a trigger point before and after intervention. SETTING: A biomedical research clinic at a university hospital. PARTICIPANTS: Subjects (N=2) from a pain clinic who had chronic headache pain. INTERVENTIONS: A single microdialysis catheter was inserted into an active MTrP of the upper trapezius to allow for continuous sampling of interstitial fluid before and after application of trigger point therapy by a massage therapist. MAIN OUTCOME MEASURES: Procedural success, pain tolerance, feasibility of intervention during sample collection, and determination of physiologically relevant values for local blood flow as well as glucose and lactate concentrations. RESULTS: Both patients tolerated the microdialysis probe insertion into the MTrP and treatment intervention without complication. Glucose and lactate concentrations were measured in the physiologic range. After intervention, a sustained increase in lactate was noted for both subjects. CONCLUSIONS: Identifying physiologic constituents of MTrPs after intervention is an important step toward understanding pathophysiology and resolution of myofascial pain. The present study forwards that aim by showing that proof-of-concept for collection of interstitial fluid from an MTrP before and after intervention can be accomplished using microdialysis, thus providing methodological insight toward treatment mechanism and pain resolution. Of the biomarkers measured in this study, lactate may be the most relevant for detection and treatment of abnormalities in the MTrP.


Subject(s)
Acupressure , Headache/metabolism , Headache/physiopathology , Myofascial Pain Syndromes/metabolism , Myofascial Pain Syndromes/therapy , Trigger Points , Adult , Female , Glucose/metabolism , Humans , Lactates/metabolism , Male , Microdialysis , Middle Aged , Pain Management , Pain Measurement , Pain Threshold , Pilot Projects , Trigger Points/blood supply
11.
Med Sci Sports Exerc ; 38(4): 660-6, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16679980

ABSTRACT

PURPOSE: Oral L-arginine supplementation has been shown to improve treadmill time to exhaustion and resting insulin sensitivity in individuals with peripheral vascular disease and type 2 diabetes, respectively. Furthermore, L-citrulline supplementation increases plasma L-arginine concentration to a level higher than that achieved by oral L-arginine supplementation. The purpose of this investigation was therefore to determine whether time to exhaustion during a graded treadmill test, as well as plasma insulin and glucose profiles, could be improved with oral L-citrulline supplementation in healthy individuals. METHODS: Seventeen young (18-34 yr), healthy male and female volunteers performed incremental treadmill tests to exhaustion following either placebo or citrulline ingestion (3 g 3 h before test, or 9 g over 24 h prior to testing). RESULTS: Steady-state submaximal respiratory exchange ratio and VO2max were not significantly different between placebo and citrulline trials. Treadmill time to exhaustion was lower following citrulline ingestion than during placebo trials (888.2 +/- 17.7 vs 895.4 +/- 17.9 s; P < 0.05; N = 17), which was accompanied by a higher rating of perceived exertion during exercise in the L-citrulline compared with the placebo condition. There was also an increase in plasma insulin in response to this high-intensity exercise in the placebo, but not in the L-citrulline, condition (P < 0.05). CONCLUSIONS: It can be concluded that, contrary to the hypothesized improvement in treadmill time following L-citrulline ingestion, there is a reduction in treadmill time following L-citrulline ingestion over the 24 h prior to testing. The normal response of increased plasma insulin following high-intensity exercise is also not present in the L-citrulline condition, indicating that L-citrulline ingestion may reduce nitric oxide-mediated pancreatic insulin secretion or increased insulin clearance.


Subject(s)
Anaerobic Threshold/drug effects , Blood Glucose/metabolism , Citrulline/administration & dosage , Exercise Test , Insulin/blood , Adolescent , Adult , Analysis of Variance , Female , Humans , Male , Plasma Volume
12.
Neuro Oncol ; 6(1): 65-74, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14769143

ABSTRACT

In individuals with brain tumors, pharmacodynamic and pharmacokinetic studies of therapeutic agents have historically used analyses of drug concentrations in serum or cerebrospinal fluid, which unfortunately do not necessarily reflect concentrations within the tumor and adjacent brain. This review article introduces to neurological and medical oncologists, as well as pharmacologists, the application of microdialysis in monitoring drug metabolism and delivery within the fluid of the interstitial space of brain tumor and its surroundings. Microdialysis samples soluble molecules from the extracellular fluid via a semipermeable membrane at the tip of a probe. In the past decade, it has been used predominantly in neurointensive care in the setting of brain trauma, vasospasm, epilepsy,and intracerebral hemorrhage. At the first Carolyn Frye-Halloran Symposium held at Massachusetts General Hospital in March 2002, the concept of microdialysis was extended to specifically address its possible use in treating brain tumor patients. In doing so we provide a rationale for the use of this technology by a National Cancer Institute consortium, New Approaches to Brain Tumor Therapy, to measure levels of drugs in brain tissue as part of phase 1 trials.


Subject(s)
Antineoplastic Agents/metabolism , Brain Neoplasms/metabolism , Microdialysis/methods , Microdialysis/standards , Animals , Antineoplastic Agents/therapeutic use , Brain Neoplasms/drug therapy , Clinical Trials, Phase I as Topic/instrumentation , Clinical Trials, Phase I as Topic/methods , Clinical Trials, Phase I as Topic/standards , Drug Evaluation, Preclinical/instrumentation , Drug Evaluation, Preclinical/methods , Drug Evaluation, Preclinical/standards , Humans , Microdialysis/instrumentation
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