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Fanny Buckinx,1,2 Mylène Aubertin-Leheudre1,2 1Département des Sciences de l’Activité Physique, Groupe de Recherche en Activité Physique Adapté, Université du Québec à Montréal (UQAM), Montréal (Qc), Canada; 2Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal (CRIUGM), Montréal (Qc), CanadaCorrespondence: Mylène Aubertin-Leheudre, Email aubertin-leheudre.mylene@uqam.caAbstract: Menopause is associated with hormonal changes, which could accelerate or lead to sarcopenia. Functional impairment and physical disability are the major consequences of sarcopenia. In order to hamper these negative health outcomes, it appears necessary to prevent and even treat sarcopenia, through healthy lifestyle changes including diet and regular physical activity or through hormonal replacement therapy when appropriate. Therefore, the purpose of this narrative review will be 1) to present the prevalence of sarcopenia in postmenopausal women; 2) to address the risk factors related to sarcopenia in this specific population; and 3) to discuss how to manage sarcopenia among postmenopausal women.Keywords: sarcopenia, menopause, hormones, physical activity, nutrition

Ageing leads to a progressive loss of muscle function (MF) and quality (MQ: muscle strength (MS)/lean muscle mass (LM)). Power training and protein (PROT) supplementation have been proposed as efficient interventions to improve MF and MQ. Discrepancies between results appear to be mainly related to the type and/or dose of proteins used. The present study aimed at determining whether or not mixed power training (MPT) combined with fast-digested PROT (F-PROT) leads to greater improvements in MF and MQ in elderly men than MPT combined with slow-digested PROT (S-PROT) or MPT alone. Sixty elderly men (age 69 (sd 7) years; BMI 18–30 kg/m2) were randomised into three groups: (1) placebo + MPT (PLA; n 19); (2) F-PROT + MPT (n 21) and (3) S-PROT + MPT (n 20) completed the intervention. LM, handgrip and knee extensor MS and MQ, functional capacity, serum metabolic markers, skeletal muscle characteristics, dietary intake and total energy expenditure were measured. The interventions consisted in 12 weeks of MPT (3 times/week; 1 h/session) combined with a supplement (30 g:10 g per meal) of F-PROT (whey) or S-PROT (casein) or a placebo. No difference was observed among groups for age, BMI, number of steps and dietary intake pre- and post-intervention. All groups improved significantly their LM, lower limb MS/MQ, functional capacity, muscle characteristics and serum parameters following the MPT. Importantly, no difference between groups was observed following the MPT. Altogether, adding 30 g PROT/d to MPT, regardless of the type, does not provide additional benefits to MPT alone in older men ingesting an adequate (i.e. above RDA) amount of protein per d. [ABSTRACT FROM AUTHOR]

We provide an evidence base and guidance for the use of menopausal hormone therapy (MHT) for the maintenance of skeletal health and prevention of future fractures in recently menopausal women. Despite controversy over associated side effects, which has limited its use in recent decades, the potential role for MHT soon after menopause in the management of postmenopausal osteoporosis is increasingly recognized. We present a narrative review of the benefits versus risks of using MHT in the management of postmenopausal osteoporosis. Current literature suggests robust anti-fracture efficacy of MHT in patients unselected for low BMD, regardless of concomitant use with progestogens, but with limited evidence of persisting skeletal benefits following cessation of therapy. Side effects include cardiovascular events, thromboembolic disease, stroke and breast cancer, but the benefit-risk profile differs according to the use of opposed versus unopposed oestrogens, type of oestrogen/progestogen, dose and route of delivery and, for cardiovascular events, timing of MHT use. Overall, the benefit-risk profile supports MHT treatment in women who have recently (< 10 years) become menopausal, who have menopausal symptoms and who are less than 60 years old, with a low baseline risk for adverse events. MHT should be considered as an option for the maintenance of skeletal health in women, specifically as an additional benefit in the context of treatment of menopausal symptoms, when commenced at the menopause, or shortly thereafter, in the context of a personalized benefit-risk evaluation. [ABSTRACT FROM AUTHOR]

Hormone-replacement therapy (HRT) attenuates the menopause-associated alterations in body composition. It is not known, however, whether this effect is a result of a concomitant increase in energy expenditure. The authors examined whether women submitted to a long-term HRT treatment presented greater energy expenditure than women who had never used HRT. We compared 13 postmenopausal women using HRT (>1 yr) with 13 age- (±2 yr) and body-mass-index-matched (BMI; ±1.5kg/m2) postmenopausal women not using HRT. Resting energy expenditure (REE; indirect calorimetry), body composition, and daily (DEE) and physical activity (PAEE) energy expenditure (accelerometry) were obtained. Although BMI, fat mass, fat-free mass, DEE, and PAEE were similar between groups, the HRT group displayed a significantly greater REE than the no-HRT group (D +222 kcal/day). In conclusion, the authors observed that a long-term treatment with HRT is associated with a greater REE in postmenopausal women. These results need to be confirmed. [ABSTRACT FROM AUTHOR]

Background: Muscle quality is a strong independent predictor of physical function. Body mass and fatness, muscle mass and cardiorespiratory fitness are known to influence muscle quality.Objective: To identify the contributors of muscle quality in young and postmenopausal women and whether hormone replacement therapy (HT) could influence this relationship at the age of menopause.Methods: Fifty-four postmenopausal women, 27 not on HT (PMW) and 27 on HT (PMW-HT), and 33 young women (YW) were evaluated for (1) body composition (body mass index, BMI), total fat mass (FM, %), appendicular lean mass (ALM, in kg and %), and appendicular skeletal mass index (ASMI = ALM/height2 in kg/m2); (2) absolute peak oxygen uptake (VO2peak, in ml/min) and relative peak oxygen uptake (VO2peakRel in ml/kg/min); and (3) absolute isometric knee extension strength (iKES in kg) and relative isometric knee extension strength (iKES/BMI and iKES/ALM).Results: YW, PMW and PMW-HT had similar BMI (32.1 ± 10.2, 27.3 ± 4.7 and 26.7 ± 4 kg/m2) and FM (39.8 ± 10.0, 39.8 ± 7.3 and 39.9 ± 7.1%), respectively. Correlations were found between iKES/BMI index and FM (r = -0.52), ALM (r = 0.32) and VO2peak (r = 0.31). Regression analysis demonstrated that, in YW, total amount of variance in iKES/BMI was mostly explained by ALM (42%), whereas, in PMW and PMW-HT, it was cumulatively explained by FM along with VO2peakRel (34 and 46%, respectively).Conclusion: The main contributors of muscle quality differ between young and postmenopausal women and HT does not seem to influence this relationship. [ABSTRACT FROM AUTHOR]

Objective The purpose of the present study was to examine the relationship between two different levels of protein intake (0.8 vs.1.2 g/kg body weight/day) with muscle mass and muscle strength. Method Seventy-two postmenopausal women were recruited. Body composition (bioelectrical impedance analysis), muscle strength (dynamometer), energy metabolism (indirect calorimetry) and dietary intake (dietary journal) were measured. We divided the women into two groups. Women with a protein intake of ≥ 1.2 g/kg body weight/day were placed in the Protein ≥ 1.2 group ( n = 35), whereas women with a protein intake of 0.8-1.19 g/kg body weight/day were categorized in the Protein 0.8-1.19 group ( n = 32). Results No significant difference was observed between groups for age, height, skeletal muscle mass, resting energy expenditure, total energy expenditure, carbohydrate and lipid intake. Significant differences between groups were observed for body mass index ( p < 0.001), fat mass ( p < 0.001) and muscle strength (hand grip and knee extensors) ( p < 0.001). More specifically, the Protein ≥ 1.2 group presented a higher muscle strength as well as a lower body mass index and fat mass compared to the Protein 0.8-1.19 group. In addition, the group with a protein intake of ≥ 1.2 g/kg body weight/day presented significantly higher energy intake ( p = 0.002), and essential ( p < 0.001) and non-essential ( p < 0.001) amino acid intake. Interestingly, when muscle strength was adjusted for essential or non-essential amino acids, differences in muscle strength persisted. Conclusion The present study indicates higher levels of muscle strength in postmenopausal women with a protein intake of ≥ 1.2 g/kg body weight/day compared to 0.8-1.19 g/kg body weight/day despite no differences in muscle mass. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the relationship of several muscle strength and cardiorespiratory fitness indices with body composition and energy expenditure in obese postmenopausal women. This was a crosssectional study involving 72 obese postmenopausal women (age: 60.0 ± 4.8 years; body mass index: 34.1 ± 3.5 kg/m 2). Muscle strength was determined by hand dynamometer and cardiorespiratory fitness was measured by indirect calorimetry. Muscle strength and cardiorespiratory fitness were expressed in absolute (kg and L/min, respectively) and in relative values (kg/ body weight (BW) and kg/lean body mass (LBM) for muscle strength and ml/min/kg BW and ml/ min kg LBM for cardiorespiratory fitness). Body composition was measured using dual energy x-ray absorptiometry. Anthropometric (waist and thigh circumference), physical activity energy expenditure and daily number of steps (SenseWear armband) as well as blood pressure were also assessed. Correlations of muscle strength and cardiorespiratory fitness indices with body composition and energy expenditure showed several similarities, however, several variations were also observed. Furthermore, our results showed that age and waist circumference were the primary independent predictors for the muscle strength indices, explaining 22-37 % of the variance and % body fat and age were the primary predictors for the cardiorespiratory fitness indices, explaining 18-40 % of the variance. In conclusion, the present study indicates that the different methods of expressing muscle strength and cardiorespiratory fitness may display several variations and similarities with body composition and energy expenditure associations. Therefore, interpretations of relationships between muscle strength and cardiorespiratory indices with body composition and energy expenditure factors should take in account the method used to express them. [ABSTRACT FROM AUTHOR]

Background: Aging is associated with reductions in muscle mass and strength, so-called sarcopenia, and is generally characterized using muscle mass index (MMI = FFM (kg) / height (m)²). It is believed that adequate nutrition especially regarding protein intake, can delay this progression and enhance the quality of life of elders. Objectives: We examined whether the predominant source of protein consumed (animal or vegetal) by older women was associated with MMI. Design: Thirty-eight healthy, normal weight, sedentary women, aged between 57-75 years (mean age: 66 ± 5 years old), and taking no medication that could influence metabolism were recruited. Body composition was measured by dual-energy X-ray absorptiometry; muscle protein content was measured by the use of creatinine excretion. Physical activity metabolism was obtained by the use of accelerometry, and indirect calorimetry. Finally, protein intake was measured with a 3-day dietary record. Results: Significant correlations were observed between MMI and body mass index, fat-free mass, muscle protein content, total protein intake, animal protein intake, fat mass, visceral fat and daily energy expenditure. However, a stepwise regression analysis showed animal protein intake to be the only independent predictor of MMI (r²=0.19; p=0.008). Conclusions: Our results suggest that protein intake, especially from animal sources, may be associated with a better preservation of MMI. However, more research is needed to confirm our results. [ABSTRACT FROM AUTHOR]

BACKGROUND AND AIM: No study to date has documented the association between short sleep duration and the risk for obesity in older people. Therefore, the aim of this study was to examine crosssectional associations between short sleep duration and variations in body fat indices in older women. METHODS: Anthropometric and body composition measurements, resting energy expenditure, daily energy expenditure, daily energy intake, plasma lipid-lipoprotein profile, and self-reported sleep duration were determined in a sample of 90 women of 50 years and above. RESULTS: The odds ratios for overweight/obesity were comparable in subjects reporting <7 hours and >/=7 hours of sleep per day, with or without adjustment for age, daily energy expenditure and daily energy intake. The results did not permit to observe any significant difference between the two sleeper groups for all the variables investigated. The correlations between sleep duration and adiposity indices were also non significant. CONCLUSIONS: Short sleep duration does not predict an increased risk of being overweight/obese in older women. This observation, together with our previously reported results in younger subjects, suggests that the sleep-body fat relationship progressively becomes less detectable with increasing in age. [ABSTRACT FROM AUTHOR]

Background: The effect of nutritional intake on sarcopenia has been mostly examined in class II sarcopenia, i.e. when muscle mass has sufficiently decreased to induce a loss in physical capacity. Although this provides important information regarding the treatment of sarcopenia, it may not help highlight mechanisms involved at the very beginning of its development. Hypothesis: We hypothesized that class l sarcopenia is associated with differences in antioxidant intakes (vitamins A, C, E and selenium) and status in healthy, older white men and women when physical activity and protein intake are taken into account. Design: Fat-free mass and total appendicular skeletal muscle mass was determined by dual-energy X-ray absorptiometry in 50 healthy, older white men (n = 16) and women (n = 34) aged 60-75 yrs. Physical activity energy expenditure (PAEE) was determined using a Caltrac accelerometer over a 3-d period. Dietary protein and antioxidant intakes were estimated from a 3-d food record and serum total antioxidant activity (TAA) was measured by a ferrylmyoglobin- ABTS assay. Results: The prevalence of class I sarcopenia was 23.5 % in women and 25.0 % in men; 12 participants were thus considered sarcopenic (4 men and 8 women) and 38 participants were considered nonsarcopenic (12 men and 26 women). Our results showed that PAEE, serum albumin concentrations, TAA, and the four antioxidants intake levels were similar between groups. On the other hand, our results showed that total protein intake was significantly higher (P < 0.01) in the non-sarcopenic group than in the sarcopenic group. Also, the number of Recommended Dietary Allowances (RDAs) reached for the antioxidant nutrients and protein intakes by the non-sarcopenic group was significantly higher (P < 0.01) than in the sarcopenic group. Conclusions: Although there were no significant differences between the sarcopenic and the non-sarcopenic group when antioxidant intakes were considered individually, we observed that the number of RDAs reached for antioxidant micronutrients and protein in healthy, older white men and women was lower in sarcopenic than nonsarcopenic individuals. Our results also suggest that a higher total dietary protein intake is associated with the preservation of muscle mass loss although both groups displayed values above actual RDAs. Obviously, prospective studies are needed to determine the minimum amount of protein in the diet needed to prevent class I sarcopenia and to examine the utility of antioxidant intake to combat the age-related loss in skeletal muscle mass. [ABSTRACT FROM AUTHOR]

PHA-stimulated peripheral blood mononuclear cells (PBMCs) are widely used for investigating replication and neutralization of HIV primary isolates in vitro. The objective of this study was to identify the T lymphocyte subset(s) that are found infected after one replication cycle by either R5- or X4-HIV-1 variants in PHA-stimulated PBMCs from healthy donors. Infected T lymphocytes were detected by intracellular p24 staining and characterized by cell surface immunophenotyping using flow cytometry. The predominant lymphocyte subset expressing p24 after 24 h of infection with either R5 or X4 HIV-1 strains was found to exhibit mainly the memory CD45RO phenotype, a greater percentage of CD62L+CD45RO+ central memory T lymphocytes was infected with X4 HIV strains. Although some CD45RA+ lymphocytes were also infected, these cells co-expressed CD45RO+. The proportion of lymphocytes expressing CD4 and CD4/CD45RO decreased by 20% after 24 h of infection. A 2-fold decrease of CD4+CD8+ T lymphocytes could also be recorded, even though this subset accounted for less than 5% of total lymphocytes in control cultures. Moreover, CD4+CD8+ T cells further decreased by 90% after 4 days of infection, a time at which they scored p24+. Therefore, our results indicate that the in vitro infection system of PHA-stimulated PBMC utilized in neutralization assays provides an appropriate model for the study of infected CD45RO+ lymphocytes but not CD45RA+ lymphocytes. [ABSTRACT FROM AUTHOR]

Hormonal replacement therapy (HRT) helps to prevent osteoporosis. The effect of short-term discontinuation of a long-term HRT on bone mineral density (BMD) in healthy post-menopausal women is unknown. Fifteen women on HRT (HRT users), 17 who never used HRT (non-users) and 8 former HRT users (past-HRT users) were recruited. BMD was measured by DXA. Our results allow to hypothesize that BMD may decline after short-term HRT discontinuation, which would increase the fracture risks. Indeed, our results show that past-HRT users are osteopenic just as non-users. However, these results should be re-examined using a prospective trial and a larger sample size. [ABSTRACT FROM AUTHOR]

A series of 2′,3′-didehydro-2′,3′-dideoxynucleosides substituted with an alkynylhydroxy- (6, 7, 12 and 13) and alkynylamino- (20) groups at the C-5 position were synthesized. All these five target modified nucleosides were tested for anti-human immunodeficiency virus type 1 activity in CEM-SS and MT-4 cells and unfortunately displayed no improvement in antiviral activity. [ABSTRACT FROM AUTHOR]

Synthesis, biological activities and decomposition kinetics of novel phosphotriester derivatives of 3′-azido-2′,3′-dideoxythymidine (AZT) bearing a S-tButyl-2-thioethyl (tBuSATE) group and L-tyrosinyl residues are reported. All the derivatives appeared to be potent inhibitors of HIV-1 replication in various cell culture experiments. The proposed decomposition process of these mixed phosphotriesters may involve successively an esterase and then a phosphodiesterase activation. [ABSTRACT FROM AUTHOR]

Expected for the ability to inhibit HIV replication, we report the synthesis of two heterodimers of the general formula: [2NRTI]-C5-GLY-SUCCINYL-Npiperazinyl-[NNRTI] (18, 19) containing both a Nucleoside Reverse Transcriptase Inhibitor (10, 11) and a Non-Nucleoside Reverse Transcriptase Inhibitor (8) [Trovirdine Analogue belonging of the phenethyl thiazolyl thiourea class] connected through the “succinyl-glycine” spontaneously cleavable linker. [ABSTRACT FROM AUTHOR]