B-hydroxy-B-methylbutyrate

OBJECTIVES: The objective of this study was to perform a systematic review to investigate the effects protein, essential amino acids (EAA), β-hydroxy β-methylbutyrate (HMB), creatine, dehydroepiandrosterone (DHEA) and fatty acid supplementation on muscle mass, muscle strength and physical performance of elderly subjects. METHODS: Using the electronic databases MEDLINE and EMBASE we identified RCTs published until February 2016 which assessed the effects of these nutrient supplementation on muscle strength, muscle mass or physical performance...

BACKGROUND/OBJECTIVES: Vascular endothelial function declines with advancing age, due in part to increased oxidative stress and inflammation, and this age-related vascular dysfunction has been identified as an independent risk factor for cardiovascular diseases. This double-blind, placebo-controlled trial investigated the effects of a dietary supplement containing β-hydroxy-β-methylbutyrate (HMB), glutamine and arginine on endothelial-dependent vasodilation of older adults. SUBJECTS/METHODS: A total of 31 community-dwelling men and women aged 65-87 years were randomly assigned to two groups...

β-Hydroxy-β-methylbutyrate (HMB) has been shown to enhance cell survival, differentiation and protein turnover in muscle, mainly activating phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) and mitogen-activated protein kinases/ extracellular-signal-regulated kinases (MAPK/ERK) signaling pathways. Since these two pathways are related to neuronal survival and differentiation, in this study, we have investigated the neurotrophic effects of HMB in mouse neuroblastoma Neuro2a cells. In Neuro2a cells, HMB promotes differentiation to neurites independent from any effects on proliferation...

INTRODUCTION: although -hydroxy--methylbutyrate (HMB) is generally marketed as a supplement for increasing muscle mass and strength, it is still not fully understood how and in which particular sports and conditions HMB can be more effective. AIMS: the primary purpose of this review is to update and summarize the current knowledge about the usefulness of HMB and to organize this information by different sports with specific reference to sports with high wear and tear phenomena as soccer, rugby or football...

OBJECTIVES: Soldiers lose muscle and bone density during sustained operations. We investigated the impact of β-hydroxy-β-methylbutyrate (HMB) on bone properties, muscle mass, and markers of skeletal muscle regeneration under simulated military sustained operations. METHODS: Male mice were divided into four groups (10/group): (1) ALT = ad libitum + trained (1h/d for 3 d/wk); (2) ALTH = ALT + HMB (0.5 g/kg BW/d); (3) C = caloric restricted (-30%) + trained (6h/d, 6d/wk); and (4) CH = C + HMB...

OBJECTIVE: To compare pressure ulcer healing rates in patients supplemented with a specialised amino acid mixture containing (beta)-hydroxy (beta)-methylbutyrate (HMB), arginine and glutamine, and standard oral nutritional supplements versus patients supplemented with oral nutritional supplements and a placebo mixture. METHOD: Twenty-three inpatients with stage II, III or IV pressure ulcers in an acute care hospital were randomised to recieve (A) a HMB, arginine and glutamine mixture twice daily alongside oral nutritional supplements (n=11) or (B) standard nutritional care alongside oral nutritional supplements (n=12) for 2 weeks...

OBJECTIVE: This prospective randomized Phase II study was designed to evaluate the preventive effect of an oral nutrition supplement composed of beta-hydroxy-beta-methylbutyrate, arginine and glutamine (beta-hydroxy-beta-methylbutyrate/arginine/glutamine) on radiation dermatitis in head and neck cancer patients. METHODS: Forty patients with histologically proven head and neck cancer, treated with concurrent chemoradiotherapy involving cisplatin were recruited. They were randomly assigned to the beta-hydroxy-beta-methylbutyrate/arginine/glutamine supplement treatment group (Group A) or the control group that received no supplement (Group B)...

The AMPK-Sirt1 pathway is an important regulator of energy metabolism and therefore a potential target for prevention and therapy of metabolic diseases. We recently demonstrated leucine and its metabolite β-hydroxy-β-methylbutyrate (HMB) to synergize with low-dose resveratrol (200 nM) to activate sirtuin signaling and stimulate energy metabolism. Here we show that leucine exerts a direct effect on Sirt1 kinetics, reducing its Km for NAD(+) by >50% and enabling low doses of resveratrol to further activate the enzyme (p = 0...

The larval osmeterial secretions of sixPapilio species examined displayed a remarkable qualitative change at the fourth larval ecdysis. The secretions of 4th (penultimate) instar larvae ofP. machaon, P. memnon, P. helenus, P. bianor, andP. maackii principally comprised mono- and/or sesquiterpenoids. The compounds identified from these species included α-pinene, sabinene, β-myrcene, limonene, β-phellandrene, (Z)-β-ocimene, (E)-β-ocimene, β-elemene, β-caryophyllene, (E)-β-farnesene, β-selinene, (E,E)-α-farnesene, germacrene-A, germacrene-B, caryophyllene oxide, methyl 3-hydroxy-n-butyrate, and acetic acid...

Glucocorticoid (GC) excess alters glucose homeostasis and promotes modifications in murinometric and anthropometric parameters in rodents and humans, respectively. β-hydroxy-β-methylbutyrate (HMB), a leucine metabolite, has been proposed as a nutritional strategy for preventing muscle wasting, but few data regarding its effects on glucose homeostasis are available. Here, we analyzed whether the effects of GC excess on glucose homeostasis may be attenuated or exacerbated by the concomitant ingestion of HMB...

Treatment of the ether-insoluble resin glycoside (convolvulin) fraction from seeds of Quamoclit pennata (Convolvulaceae) with indium(III) chloride in methanol provided three oligoglycosides of hydroxy fatty acid (glycosidic acid) methyl esters and two methyl glycosides, which were partially acylated by a glycosidic acid, 7S-hydroxydecanoic acid 7-O-β-D-quinovopyranoside (quamoclinic acid B) and/or two organic acids, (E)-2-methylbut-2-enoic (tiglic) acid and/or 3R-hydroxy-2R-methylbutyric (nilic) acid. Their structures were elucidated on the basis of spectroscopic data and chemical conversions...

BACKGROUND: Evidence suggests CaHMB may impact muscle mass and/or strength in older adults, yet no long-term studies have compared its effectiveness in sedentary and resistance training conditions. The purpose of this study was to evaluate the effects of 24 weeks of CaHMB supplementation and resistance training (3 d wk(-1)) or CaHMB supplementation only in ≥65 yr old adults. METHODS: This double-blinded, placebo-controlled, trial occurred in two phases under ad libitum conditions...

Maintenance of skeletal muscle mass is contingent upon the dynamic equilibrium (fasted losses-fed gains) in protein turnover. Of all nutrients, the single amino acid leucine (Leu) possesses the most marked anabolic characteristics in acting as a trigger element for the initiation of protein synthesis. While the mechanisms by which Leu is 'sensed' have been the subject of great scrutiny, as a branched-chain amino acid, Leu can be catabolized within muscle, thus posing the possibility that metabolites of Leu could be involved in mediating the anabolic effect(s) of Leu...

Position Statement: The International Society of Sports Nutrition (ISSN) bases the following position stand on a critical analysis of the literature on the use of beta-hydroxy-beta-methylbutyrate (HMB) as a nutritional supplement. The ISSN has concluded the following. 1. HMB can be used to enhance recovery by attenuating exercise induced skeletal muscle damage in trained and untrained populations. 2. If consuming HMB, an athlete will benefit from consuming the supplement in close proximity to their workout...

The purpose of the present study was to determine the effects of short-term supplementation with the free acid form of b-hydroxyb-methylbutyrate (HMB-FA) on indices of muscle damage, protein breakdown, recovery and hormone status following a high-volume resistance training session in trained athletes. A total of twenty resistance-trained males were recruited to participate in a high-volume resistance training session centred on full squats, bench presses and dead lifts. Subjects were randomly assigned to receive either 3 g/d of HMB-FA or a placebo...

Older women exhibit blunted skeletal muscle hypertrophy following resistance training (RT) compared to other age and gender cohorts that is partially due to an impaired regenerative capacity. In the present study, we examined whether β-hydroxy-β-methylbutyrate (HMB) provision to aged female rodents would enhance regenerative mechanisms and facilitate RT-induced myofiber growth. Nineteen-month old female Sprague-Dawley rats were randomly divided into three groups: HMB (0.48 g/kg/d; n = 6), non-HMB (n = 6), and control (n = 4)...

PURPOSE: To determine the effects of 16 wk. of beta-hydroxy-beta-methylbutyrate (HMB) administration on age-related changes in functionality and diffusion tensor imaging (DTI) determined myofiber dimensions. METHODS: Twelve young (44 wk.), 6 middle-aged (60 wk.), 10 old (86 wk.), and 5 very old (102 wk.) male Fisher-344 rat's body composition and grip strength were assessed at baseline. Following, 6 young, 6 middle-aged, 5 old and 5 very old rats were sacrificed for baseline myofiber dimensions and gene transcript factor expression in the soleus (SOL) and gastrocnemius (GAS)...

β-Hydroxy-β-methylbutyrate (HMB) is a leucine metabolite that may have a positive effect in protein catabolic conditions. Therefore, we hypothesized that HMB treatment could attenuate the sepsis-induced protein catabolic state. The aims of our study were to elucidate the effect of HMB in healthy and septic animals and to evaluate the differences in the action of HMB in different muscle types. Intact and septic (5 mg endotoxin/kg i.p.) rats were administered with HMB (0.5 g/kg/day) or saline. After 24 h, extensor digitorum longus (EDL) and soleus (SOL) muscles were isolated and used for determination of total and myofibrillar proteolysis, protein synthesis, leucine oxidation, activity of cathepsins B and L, chymotrypsin-like activity, and expression of α-subunits of proteasome...

BACKGROUND: While chronic β-Hydroxy β-Methylbutyrate (HMB) supplementation (≥ 2 wk) lowers exercise induced muscle damage, its acute or timing effects have not been examined. The purpose of this study was to investigate the acute and timing effects of oral HMB supplementation on serum creatine kinase (CK), lactate dehydrogenase (LDH), muscle soreness, and maximal voluntary contraction (MVC). METHODS: Sixteen non-resistance trained men (22 ± 2 yrs) were assigned to HMB-Pre or HMB-Post groups...

Cancer cachexia syndrome contributes to wasting and weight loss leading to inefficacy of anticancer therapy. In this study, the anticatabolic agent beta-hydroxy-beta-methylbutyrate (HMB) was supplemented to adult Walker 256 tumor-bearing rats during 8 weeks aiming to determine if tumor burden could be reduced. Male Wistar rats were randomly assigned to nontumor and tumor-bearing groups and fed regular chow or regular chow plus HMB supplemented (76 mg/kg body weight). Beta-hydroxy-beta-methylbutyrate supplementation induced a lower tumor weight and tumor cell proliferation ex vivo, totally prevented glycemia reduction, as well as blunted the increase in the serum lactate concentrations and also preserved glycogen stores in tumor-bearing rats...