The Interplay between Magnesium and Testosterone in Modulating Physical Function in Men

Association between dietary magnesium intake, inflammation, and neurodegeneration

BACKGROUND

Consistent evidence shows that magnesium (Mg) intake is associated with lower blood pressure (BP), and that lower BP is associated with improved cerebral health. However, recent findings indicate that the positive effect of dietary Mg intake on cerebral health is not mediated by a decrease in BP. As Mg's anti-inflammatory action is a plausible alternative mechanism, the objective of this study was to investigate the associations between Mg intake and inflammation to determine whether it mediates any neuroprotective effect.

METHODS

Participants from the UK Biobank (n = 5775, aged 40-73 years, 54.7% female) were assessed for dietary magnesium using an online food questionnaire, brain and white matter lesion (WML) volumes were segmented with FreeSurfer software, and inflammation markers including high-sensitivity C-reactive protein (hs-CRP), leukocyte, erythrocyte count, and Glycoprotein acetylation (GlycA) were measured using specific laboratory techniques such as immunoturbidimetry, automated cell counting, and nuclear magnetic resonance. Hierarchical linear regression models were performed to investigate the association between dietary Mg, and inflammatory markers and between dietary Mg, brain and WMLs volumes. Mediation analysis was performed to test a possible mediation role of inflammation on the association between dietary Mg and brain and WMLs volumes.

RESULTS

Higher dietary Mg intake was associated with lower inflammation: hs-CRP level (- 0.0497%; 95% confidence interval [CI] - 0.0497%,  - 0.0199%) leukocytes count (- 0.0015%; 95%CI - 0.00151%,  - 0.0011%), and GlycA (- 0.0519%; 95%CI - 0.1298%,  - 0.0129%). Moreover, higher dietary Mg intake was associated with larger grey matter volume (0.010%; 95%CI 0.004%, 0.017%), white matter volume (0.012%; 95%CI 0.003,  0.022) and right hippocampal volume (0.002%; 95%CI 0.0007, -0.0025%). Lower hs-CRP levels mediated the positive association between higher dietary Mg intake and larger grey matter volume.

CONCLUSIONS

The anti-inflammatory effects of dietary Mg intake in the general population, appears to mediate its neuroprotective effect.

The magnesium depletion score is associated with increased likelihood of kidney stone disease among female adults

OBJECT

The association between magnesium depletion score (MDS) and kidney stone disease (KSD) remains unknown. This study was designed to investigate the association of MDS with KSD in adults.

METHODS

A total of 19,654 participants were enrolled from the National Health and Nutrition Examination Surveys (NHANES). The MDS was calculated by assessing four aspects, including alcohol assumption, renal function, and use of diuretics and proton pump inhibitor. Multivariable logistic regressions were performed to explore the associations between MDS and the prevalence of KSD. Linear correlations were conducted explore the relationship of testosterone with MDS.

RESULTS

In the multivariable logistic regressions with full adjustment for confounding variables, the odds ratio of MDS associating with KSD was 1.28 (95% CI: 1.04-1.58, P = 0.022) in total population, and 1.70 (95% CI: 1.16-2.50, P=0.007) in female participants. Besides, compared to the lowest MDS, the highest MDS was associated with a lower testosterone (β = -16.39, P=0.009) after full adjustment in non-menopause women.

CONCLUSION

This study highlighted a positive correlation of high MDS with KSD in female population, which may be associated low level of serum testosterone.

Levels of elements in selected food substances that support usage in the management and treatment of erectile dysfunction

BACKGROUND

The use of fruits and vegetables for the management and treatment of erectile dysfunction has gained popularity due to the cheaper cost, accessibility and perceived absence of side effects. Much of the work done on plant-based aphrodisiacs has focused on the phytochemistry of secondary metabolites.

AIM

This work sought to analyze selected fruits and vegetables that are commonly used in the management of erectile dysfunction in Ghana and quantify the levels of some micro- and macro-elements necessary for good penile health in order to determine the usefulness or otherwise of the selected produce.

METHODS

Energy-dispersive X-ray fluorescence spectroscopy was used to detect and quantify the levels of potassium (K), calcium (Ca), selenium (Se), magnesium (Mg), iron (Fe), and zinc (Zn) in carrot roots, cucumber fruit, garlic bulb, ginger rhizome, nutmeg fruit, sweet potato tuber, tiger nut tuber and watermelon fruit.

RESULTS

The analysis revealed the presence of K, Ca, Mg, Fe and Zn. Levels of Se were below detection. The concentration of K was the highest in each of the food substances. However, in terms of recommended daily allowance, Mg had the highest contribution. Cucumber fruit and the rind of watermelon fruit had the highest levels of micro- and macro-elements implicated in erectile dysfunction.

CONCLUSION

The potential use of these foods to treat and manage erectile dysfunction may not only be due to the presence of phytochemicals alone but also the presence of significant levels of micro- and macro-elements required for good penile health.

Concentrations of Bioelements (Zn, Cu, Fe, Cr, Mg, Mn) in Serum and Bone Tissue of Aging Men Undergoing Hip Arthroplasty: Implications for Erectile Dysfunction

Background: Erectile dysfunction (ED) stands out as one of the most prevalent sexual disorders in men, with its incidence progressively escalating with age. As delineated by the International Consultation Committee for Sexual Medicine on Definitions/Epidemiology/Risk Factors for Sexual Dysfunction, the prevalence of ED among men under 40 years is estimated to be within the range of 1-10%. The aim of this study was to determine the relationship between the concentration of bioelements (Zn, Cu, Fe, Cr, Mg, and Mn) in the serum and bone tissue and the concentration of selected hormones in men with and without erectile dysfunction. Materials and methods: The retrospective cohort study included 152 men who underwent total hip arthroplasty for hip osteoarthritis at the Department of Orthopaedic Traumatology and Musculoskeletal Oncology at the Pomeranian Medical University in Szczecin. Certain exclusion criteria were applied to ensure the integrity of the study. These included individuals with diabetes, a history of cancer, alcohol abuse, liver or kidney failure, New York Heart Association (NYHA) class III or IV heart failure, and those taking medications that affect bone metabolism, such as mineral supplements, neuroleptics, chemotherapeutic agents, immunosuppressants, corticosteroids, or antidepressants. Patients with hypogonadism or infertility were excluded from the study. Results: The study showed an association between bioT concentrations and Cu concentrations in both patients with and without erectile dysfunction. A correlation between bioactive testosterone and Cr concentrations was also observed in both groups. Patients with erectile dysfunction showed a relationship between bioT concentration and Zn concentration, TT concentration and Mn concentration, FT concentration and Zn concentration, and E2 concentration and Cr concentration. An analysis of elemental concentrations in bone tissue showed an association between FT and Mg and Mn concentrations, but only in patients with erectile dysfunction. In patients without erectile dysfunction, a correlation was observed between FT and Cu concentrations. A correlation was also observed between bioT concentrations and Mg, Mn, and Zn concentrations, but only in patients with erectile dysfunction. In patients without erectile dysfunction, a correlation was observed between bioT and Cu concentrations. Conclusions: Studying the relationship between the concentration of bioelements (Zn, Cu, Fe, Cr, Mg, and Mn) in the serum and bone tissue and the concentration of selected hormones in men may be important in explaining the etiology of the problem. The study of the concentration of Zn and Cu in bone tissue and serum showed that these two elements, regardless of the place of accumulation, may be related to the concentration of androgens in men.

Nonpharmacological Interventions for the Management of Testosterone and Sperm Parameters: A Scoping Review

PURPOSE

Testosterone replacement and associated pharmacologic agents are effective strategies to treat male hypogonadism; however, nutraceutical agents and lifestyle modification approaches have gained medical interest. The purpose of this scoping review is to highlight the evidence (or lack thereof) of nutraceuticals and lifestyle modification approaches in the management of testosterone levels and sperm parameters.

METHODS

A scoping review of nonpharmacologic interventions (supplements, herbal medicines, diets, sleep, and exercise) with the potential to improve male health was undertaken to elucidate changes in testosterone levels and sperm parameters in men with hypogonadism or infertility compared with healthy patients.

FINDINGS

A multitude of nutraceuticals and functional nutrients are purported to stimulate testosterone production; however, only a select few have had promising results, such as zinc, vitamin D (in case of hypovitaminosis D), l-arginine, mucuna, and ashwagandha, based on well-controlled randomized clinical trials of men with low testosterone levels and related problems. Except for l-arginine, these natural agents, as well as tribulus and ω3 fatty acids, can improve some degree of sperm parameters in infertile men. Before implementing these nutraceutical agents, adequate sleep, exercise, and weight loss in patients with obesity are imperative. The effects of nonpharmacologic interventions on testosterone levels are modest and hence do not directly translate into clinical benefits. Correspondingly, androgen receptor content, but not endogenous androgens, has been regarded as the principal factor in muscle hypertrophy.

IMPLICATIONS

A limited number of supplements and herbal medicines can be considered as adjunctive approaches in the management of testosterone levels and sperm parameters, primarily in men with low testosterone levels and infertility, whereas most nonpharmacologic supplements appear to lack evidence. Although proper physical exercise, sleep, and diet are indisputable approaches because of the general benefits to health, the use of nutraceuticals, if considered, must be personalized by physicians and/or registered dietitians.

D-aspartic Acid Supplementation Effects on Body Composition: A Systematic Review of Randomized Clinical Trials on Trained Males

Context: D-Aspartic acid (DAA) is an amino acid found in the brain and reproductive system. Some investigations have reported beneficial effects of DAA on brain function and reproductive system health by increasing testosterone through the hypothalamic-pituitary-gonadal axis. However, its effect on body composition is unknown. Given testosterone's role in muscle growth, this study aimed to evaluate the effect of DAA supplementation on the body composition of trained males. Evidence Acquisition: PubMed, Scopus, Embase, and Web of Science (until 1 August 2021) were searched for this systematic review. Inclusion criteria assumed as clinical trials assessed the effect of DAA on body composition in trained males. After including articles by keywords, the articles were reviewed for meeting the eligibility criteria. Three independent researchers conducted the search and full-text review. Results: Among 134 articles located during the primary search, five articles (47 interventions and 43 controls) were included in the study based on eligibility criteria. All included clinical trials had a low risk of bias. A review of the relevant literature concludes that different doses of DAA (three grams, six grams, 7.12, and 12 grams) in different intervention periods (two weeks, four weeks, and 12 weeks) have no effects on body composition in trained males. Conclusions: DAA supplementation is a low-level booster of testosterone and has no significant effect on the testosterone level in professional male athletes, and cannot alter the body composition.

Manipulation of Dietary Intake on Changes in Circulating Testosterone Concentrations

Elevations in the circulating concentration of androgens are thought to have a positive effect on the anabolic processes leading to improved athletic performance. Anabolic-androgenic steroids have often been used by competitive athletes to augment this effect. Although there has been concerted effort on examining how manipulating training variables (e.g., intensity and volume of training) can influence the androgen response to exercise, there has been much less effort directed at understanding how changes in both macronutrient and micronutrient intake can impact the androgen response. Thus, the focus of this review is to examine the effect that manipulating energy and nutrient intake has on circulating concentrations of testosterone and what the potential mechanism is governing these changes.

Associations Between Serum Magnesium Concentrations and Polycystic Ovary Syndrome Status: a Systematic Review and Meta-analysis

Magnesium (Mg) is the second most frequent intracellular cation in humans with a critical role in insulin metabolism and glucoregulation. Women with polycystic ovary syndrome (PCOS) often present with insulin resistance and impaired glucoregulatory status; however, their Mg status remains unclear. Therefore, we aimed to conduct a systematic review and meta-analysis to evaluate serum Mg concentration in women with PCOS and compare it with that of controls without PCOS. Online databases of PubMed, Scopus, Cochrane Library, and ISI Web of Science were searched for studies evaluating the relationship between Mg concentrations and PCOS status until October 2019. Pooled weighted mean differences (WMDs) of serum Mg levels were calculated using random effects models. A total of eight studies (10 arms; n = 2026 women) were included. Pooled effect sizes, expressed as WMD and 95% CI, revealed decreased serum Mg concentrations in women with PCOS compared with controls (- 0.09 (- 0.17, - 0.02) mmol/L; P = 0.01). However, significant heterogeneity was detected across the studies (I ² = 98.0%, P < 0.001). Despite the classification of studies based on baseline BMI classes, we did not detect the potential source of the observed heterogeneity. Subgroup analysis showed that overweight and obese women (BMI ≥ 25 kg/m², 0.07 mmol/L (- 0.14, - 0.01); P = 0.02) with PCOS had lower magnesium concentrations than normal women (BMI < 25 kg/m², - 0.11 (- 0.25, 0.04) mmol/L; P = 0.14) compared with the control group. Serum Mg concentrations appear to be declined in overweight or obese women with PCOS, which may warrant screening and management of Mg status in this clinical population. High-quality studies are needed to elucidate the relationship between Mg concentrations and the development of PCOS.

Comparison of biotechnological culture of hypoxia-conditioned rat mesenchymal stem cells with conventional in vitroculture of normoxia-conditioned rat mesenchymal stem cells for testicular failure therapy with low libido in rats

Aim:

Biotechnological culture of hypoxia-conditioned (CH) rat mesenchymal stem cells (rMSC-CH) for testicular failure therapy with low libido improves the functional outcome of the testicle for producing spermatogenic cells and repairs Leydig cells in rats (Rattus norvegicus).

Materials and Methods:

In the first group (T1), rats with testicular failure and low libido were injected with normoxia-conditioned (CN) rMSCs (21% oxygen); in the second group (T2), rats with testicular failure and low libido were injected with rMSC-CH (1% oxygen); in the negative control group (T−), rats with normal testis were injected with 0.1 mL phosphate-buffered saline (PBS); and in the sham group (TS), rats with testicular failure and low libido were injected with 0.1 mL of PBS.

Results:

Vascular endothelial growth factor expression, as the homing signal, in the groups T2, T−, T1, and TS was 2.00±0.5%, 2.95±0.4%, 0.33±0.48%, and 0±0%, respectively. The number of cluster of differentiation (CD)34⁺ and CD45⁺ cells in the groups T− and TS was <20%, whereas that in T1 and T2 groups was >30% and >80%, respectively, showing the mobilization of hematopoietic stem cells (HSCs). The number of spermatogenic cells (spermatogonia, primary spermatocytes, secondary spermatocytes, and spermatid) decreased significantly (p<0.05) in TS compared with that in T−, T1, and T2, whereas that in T2 did not show a significant (p>0.05) decrease compared to that in T−. The improvement in libido, based on the number of Leydig cells producing the hormone testosterone for libido expression, did not increase in T1, whereas T2 was able to maintain the number of Leydig cells significantly compared to that between TS and T1.

Conclusion:

rMSC-CH culture for testicular failure with low libido showed improvement in the functional outcome of the testicle and in repairing Leydig cells.

Supplements with purported effects on muscle mass and strength

PURPOSE

Several supplements are purported to promote muscle hypertrophy and strength gains in healthy subjects, or to prevent muscle wasting in atrophying situations (e.g., ageing or disuse periods). However, their effectiveness remains unclear.

METHODS

This review summarizes the available evidence on the beneficial impacts of several popular supplements on muscle mass or strength.

RESULTS

Among the supplements tested, nitrate and caffeine returned sufficient evidence supporting their acute beneficial effects on muscle strength, whereas the long-term consumption of creatine, protein and polyunsaturated fatty acids seems to consistently increase or preserve muscle mass and strength (evidence level A). On the other hand, mixed or unclear evidence was found for several popular supplements including branched-chain amino acids, adenosine triphosphate, citrulline, β-Hydroxy-β-methylbutyrate, minerals, most vitamins, phosphatidic acid or arginine (evidence level B), weak or scarce evidence was found for conjugated linoleic acid, glutamine, resveratrol, tribulus terrestris or ursolic acid (evidence level C), and no evidence was found for other supplements such as ornithine or α-ketoglutarate (evidence D). Of note, although most supplements appear to be safe when consumed at typical doses, some adverse events have been reported for some of them (e.g., caffeine, vitamins, α-ketoglutarate, tribulus terrestris, arginine) after large intakes, and there is insufficient evidence to determine the safety of many frequently used supplements (e.g., ornithine, conjugated linoleic acid, ursolic acid).

CONCLUSION

 In summary, despite their popularity, there is little evidence supporting the use of most supplements, and some of them have been even proven ineffective or potentially associated with adverse effects.

Gender-specific association between dietary acid load and total lean body mass and its dependency on protein intake in seniors

Diet-related mild metabolic acidosis may play a role in the development of sarcopenia. We investigated the relationship between dietary acid load and total lean body mass in male and female seniors age ≥ 60 years. We found that a more alkaline diet was associated with a higher %TLM only among senior women.

INTRODUCTION

The aim of this study was to determine if dietary acid load is associated with total lean body mass in male and female seniors age ≥ 60 years.

METHODS

We investigated 243 seniors (mean age 70.3 ± 6.3; 53% women) age ≥ 60 years who participated in the baseline assessment of a clinical trial on vitamin D treatment and rehabilitation after unilateral knee replacement due to severe knee osteoarthritis. The potential renal acid load (PRAL) was assessed based on individual nutrient intakes derived from a food frequency questionnaire. Body composition including percentage of total lean body mass (%TLM) was determined using dual-energy X-ray absorptiometry. Cross-sectional analyses were performed for men and women separately using multivariable regression models controlling for age, physical activity, smoking status, protein intake (g/kg BW per day), energy intake (kcal), and serum 25-hydroxyvitamin D concentration. We included a pre-defined subgroup analysis by protein intake (< 1 g/kg BW day, > 1 g/kg BW day) and by age group (< 70 years, ≥ 70 years).

RESULTS

Adjusted %TLM decreased significantly across PRAL quartiles only among women (P _trend = 0.004). Moreover, in subgroup analysis, the negative association between the PRAL and %TLM was most pronounced among women with low protein intake (< 1 g/kg BW per day) and age below 70 years (P = 0.002). Among men, there was no association between the PRAL and %TLM.

CONCLUSION

The association between dietary acid load and %TLM seems to be gender-specific, with a negative impact on total lean mass only among senior women. Therefore, an alkaline diet may be beneficial for preserving total lean mass in senior women, especially in those with low protein intake.

Cross-sectional association of coffee and caffeine consumption with sex hormone-binding globulin in healthy nondiabetic women

OBJECTIVE

Low sex hormone-binding globulin (SHBG) is a consistent risk factor for type 2 diabetes, particularly in women. Coffee consumption has been associated with a lower risk of type 2 diabetes, but its effects on SHBG are less known.

DESIGN AND METHODS

This was a cross-sectional study of 2377 nondiabetic pre- and postmenopausal women from the E3N cohort study whose baseline SHBG was measured. Information on diet (including coffee and caffeine consumption), lifestyle and medical conditions was collected through questionnaires. The relationship between coffee and caffeine consumption and SHBG was modelled, with adjustment for covariates and stratification by body mass index (BMI) categories (< or ≥25 kg/m² ) and menopausal status.

RESULTS

The mean age was 57.2±6.4 years and 61% of the 2377 women were postmenopausal. High coffee (≥3 cups/day) and caffeine (≥265 mg/day) intakes were associated with a reduced risk of being in the 1st quartile of the SHBG level distribution (<46.3 nmol/L) in a multivariate adjusted model (OR: 0.72 [95% CI: 0.52-1.01] and OR: 0.71 [95% CI: 0.53-0.95], respectively). No association was found between tea consumption and SHBG levels. In multivariate models stratified on BMI categories and menopausal status, associations were restricted to women with a BMI ≥25 kg/m² or being postmenopausal. The association with SHBG was consistently noted with consumption of both caffeinated coffee and caffeine, but not decaffeinated coffee.

CONCLUSIONS

Consumption of high coffee and caffeine is associated with a reduced risk of low SHBG, an established risk marker for T2DM, which might contribute to the protective effects of coffee for type 2 diabetes.

The impact of hypomagnesemia on erectile dysfunction in elderly, non-diabetic, stage 3 and 4 chronic kidney disease patients: a prospective cross-sectional study

BACKGROUND

Erectile dysfunction (ED) is common in older men with chronic kidney disease. Magnesium is essential for metabolism of nitric oxide which helps in penile erection. There is little information available about the influence of serum magnesium on ED. The aim of the study was to assess the influence of hypomagnesemia on ED in elderly chronic kidney disease patients.

SUBJECTS AND METHODS

A total of 372 patients aged 65-85 years, with an estimated glomerular filtration rate of 60-15 mL/min/1.73 m², were divided into two groups according to serum magnesium levels: hypomagnesemia, n=180; and normomagnesemia, n=192. ED was assessed through the International Index of Erectile Function-5. Hypomagnesemia is defined as serum magnesium <1.8 mg/dL.

RESULTS

The prevalence of ED was higher among hypomagnesemic subjects compared to that among normomagnesemics (93.3% vs 70.8%, P<0.001). Severe ED (62.8% vs 43.8%, P=0.037), mild-to-moderate ED (12.2% vs 5.2%, P=0.016), abdominal obesity (37.2% vs 22.9%, P=0.003), metabolic syndrome (38.4% vs 19.2%, P=0.026), proteinuria (0.83±0.68 vs 0.69±0.48 mg/dL, P=0.023), and C-reactive protein (6.1±4.9 vs 4.1±3.6 mg/L, P<0.001) were high; high-density lipoprotein cholesterol (48.8±14.0 vs 52.6±13.5 mg/dL, P=0.009), and albumin (4.02±0.53 vs 4.18±0.38 g/dL, P=0.001) were low in the hypomagnesemia group. Serum magnesium ≤1.85 mg/dL was the best cutoff point for prediction of ED. Hypomagnesemia (relative risk [RR] 2.27), age ≥70 (RR 1.74), proteinuria (RR 1.80), smoking (RR 21.12), C-reactive protein (RR 1.34), abdominal obesity (RR 3.92), and hypertension (RR 2.14) were predictors of ED.

CONCLUSION

Our data support that ED is related to hypomagnesemia in elderly patients with moderately to severely reduced kidney function.

Analysis of the relationship between the blood concentration of several metals, macro- and micronutrients and endocrine disorders associated with male aging

Beyond 30 years of age, men experience a decline in the production of testosterone, yet only a few develop late-onset hypogonadism. This study was designed to determine the relationship between blood concentrations of metals, macro- and micronutrients and age-related testosterone deficiency and associated hormonal changes in aging men. The research involved 313 men aged 50-75 years. We used ELISA to determine the concentrations of total testosterone (TT), free testosterone (FT), estradiol (E2), dehydroepiandrosterone sulfate (DHEAS) and sex hormone-binding globulin (SHBG). We calculated free androgen index (FAI). With the use of emission spectrometry in inductively coupled argon plasma, we determined the whole-blood concentrations of lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As) and tungsten (W), as well as serum concentrations of magnesium (Mg), iron (Fe), calcium (Ca), copper (Cu), zinc (Zn), selenium (Se), chromium (Cr), manganese (Mn) and molybdenum (Mo). The study showed no relationship between TT and FT and the concentrations of metals. Men with TT deficiency had significantly lower concentrations of Mg and Fe and increased Mn. Men with FT deficiency had higher W and Cr levels and lower Fe. Assessing the correlation between the concentrations of hormones, SHBG and FAI, and the concentration of metals and macro- and microelements in the blood of the men, we found positive correlations between the concentrations of TT-Mg, TT-Fe, TT-Mo, FT-Fe, E2-As, SHBG-Mn, FAI-W, FAI-As, FAI-Zn and FAI-Ca, and negative correlations between the concentrations of TT-Mn, FT-Cd, FT-Cr, E2-Hg, E2-Cr, SHBG-W, SHBG-As, SHBG-Zn, SHBG-Ca, FAI-Pb and FAI-Mn. Positive correlations between As and E2 and between As and FAI may suggest a lack of association between this metal and hypogonadism in people not exposed to excess As levels. Our research indicates a positive relationship between the concentrations of Mg, Fe and Zn and endocrine system in aging men, in contrast to Mn and Cr. Toxic metals (Cd, Pb) seemed to negatively affect the level of bioavailable testosterone. In persons not exposed to As, As does not contribute late-onset hypogonadism. Heavy metals (Pb, Cd, Hg and W) may contribute to a lower concentration of DHEAS. The role of W in men with LOH was found to be ambiguous, as on the one hand its concentration was higher in men with FT deficiency, and on the other hand it positively correlated with FAI, which in turn indirectly indicates testosterone availability. Copper and selenium do not seem to play any significant role in the occurrence of TT deficiency in aging men.

Innovative biomarkers for predicting type 2 diabetes mellitus: relevance to dietary management of frailty in older adults

Type 2 diabetes mellitus (T2DM) increases in prevalence in the elderly. There is evidence for significant muscle loss and accelerated cognitive impairment in older adults with T2DM; these comorbidities are critical features of frailty. In the early stages of T2DM, insulin sensitivity can be improved by a "healthy" diet. Management of insulin resistance by diet in people over 65 years of age should be carefully re-evaluated because of the risk for falling due to hypoglycaemia. To date, an optimal dietary programme for older adults with insulin resistance and T2DM has not been described. The use of biomarkers to identify those at risk for T2DM will enable clinicians to offer early dietary advice that will delay onset of disease and of frailty. Here we have used an in silico literature search for putative novel biomarkers of T2DM risk and frailty. We suggest that plasma bilirubin, plasma, urinary DPP4-positive microparticles and plasma pigment epithelium-derived factor merit further investigation as predictive biomarkers for T2DM and frailty risk in older adults. Bilirubin is screened routinely in clinical practice. Measurement of specific microparticle frequency in urine is less invasive than a blood sample so is a good choice for biomonitoring. Future studies should investigate whether early dietary changes, such as increased intake of whey protein and micronutrients that improve muscle function and insulin sensitivity, affect biomarkers and can reduce the longer term complication of frailty in people at risk for T2DM.

Multiple hormonal dysregulation as determinant of low physical performance and mobility in older persons

Mobility-disability is a common condition in older individuals. Many factors, including the age-related hormonal dysregulation, may concur to the development of disability in the elderly. In fact, during the aging process it is observed an imbalance between anabolic hormones that decrease (testosterone, dehydroepiandrosterone sulphate (DHEAS), estradiol, insulin like growth factor-1 (IGF-1) and Vitamin D) and catabolic hormones (cortisol, thyroid hormones) that increase. We start this review focusing on the mechanisms by which anabolic and catabolic hormones may affect physical performance and mobility. To address the role of the hormonal dysregulation to mobility-disability, we start to discuss the contribution of the single hormonal derangement. The studies used in this review were selected according to the period of time of publication, ranging from 2002 to 2013, and the age of the participants (≥65 years). We devoted particular attention to the effects of anabolic hormones (DHEAS, testosterone, estradiol, Vitamin D and IGF-1) on both skeletal muscle mass and strength, as well as other objective indicators of physical performance. We also analyzed the reasons beyond the inconclusive data coming from RCTs using sex hormones, thyroid hormones, and vitamin D (dosage, duration of treatment, baseline hormonal values and reached hormonal levels). We finally hypothesized that the parallel decline of anabolic hormones has a higher impact than a single hormonal derangement on adverse mobility outcomes in older population. Given the multifactorial origin of low mobility, we underlined the need of future synergistic optional treatments (micronutrients and exercise) to improve the effectiveness of hormonal treatment and to safely ameliorate the anabolic hormonal status and mobility in older individuals.