Statin-Associated Myopathy: Emphasis on Mechanisms and Targeted Therapy.

Hyperlipidemia is a major risk factor for cardiovascular morbidity and mortality. Statins are the first-choice therapy for dyslipidemias and are considered the cornerstone of atherosclerotic cardiovascular disease (ASCVD) in both primary and secondary prevention. Despite the statin-therapy-mediated positive effects on cardiovascular events, patient compliance is often poor. Statin-associated muscle symptoms (SAMS) are the most common side effect associated with treatment discontinuation. SAMS, which range from mild-to-moderate muscle pain, weakness, or fatigue to potentially life-threatening rhabdomyolysis, are reported by 10% to 25% of patients receiving statin therapy. There are many risk factors associated with patient features and hypolipidemic agents that seem to increase the risk of developing SAMS. Due to the lack of a "gold standard", the diagnostic test for SAMS is based on a clinical criteria score, which is independent of creatine kinase (CK) elevation. Mechanisms that underlie the pathogenesis of SAMS remain almost unclear, though a high number of risk factors may increase the probability of myotoxicity induced by statin therapy. Some of these, related to pharmacokinetic properties of statins and to concomitant therapies or patient characteristics, may affect statin bioavailability and increase vulnerability to high-dose statins.

Unacylated ghrelin normalizes skeletal muscle oxidative stress and prevents muscle catabolism by enhancing tissue mitophagy in experimental chronic kidney disease.

Unacylated ghrelin (UnAG) may lower skeletal muscle oxidative stress, inflammation, and insulin resistance in lean and obese rodents. UnAG-induced autophagy activation may contribute to these effects, likely involving removal of dysfunctional mitochondria (mitophagy) and redox state maintenance. In chronic kidney disease (CKD) oxidative stress, inflammation and insulin resistance may negatively influence patient outcome by worsening nutritional state through muscle mass loss. Here we show in a 5/6 nephrectomy (Nx) CKD rat model that 4 d s.c. UnAG administration (200 µg twice a day) normalizes CKD-induced loss of gastrocnemius muscle mass and a cluster of high tissue mitochondrial reactive oxygen species generation, high proinflammatory cytokines, and low insulin signaling activation. Consistent with these results, human uremic serum enhanced mitochondrial reactive oxygen species generation and lowered insulin signaling activation in C2C12 myotubes while concomitant UnAG incubation completely prevented these effects. Importantly, UnAG enhanced muscle mitophagy in vivo and silencing RNA-mediated autophagy protein 5 silencing blocked UnAG activities in myotubes. UnAG therefore normalizes CKD-induced skeletal muscle oxidative stress, inflammation, and low insulin signaling as well as muscle loss. UnAG effects are mediated by autophagy activation at the mitochondrial level. UnAG administration and mitophagy activation are novel potential therapeutic strategies for skeletal muscle metabolic abnormalities and their negative clinical impact in CKD.-Gortan Cappellari, G., Semolic, A., Ruozi, G., Vinci, P., Guarnieri, G., Bortolotti, F., Barbetta, D., Zanetti, M., Giacca, M., Barazzoni, R. Unacylated ghrelin normalizes skeletal muscle oxidative stress and prevents muscle catabolism by enhancing tissue mitophagy in experimental chronic kidney disease.

Unacylated Ghrelin: A Novel Regulator of Muscle Intermediate Metabolism With Potential Beneficial Effects in Chronic Kidney Disease.

In patients with chronic kidney disease (CKD), malnutrition with loss of skeletal muscle mass has a negative impact on morbidity and mortality. Emerging evidence indicates that a cluster of oxidative stress, inflammation, and insulin resistance directly contributes to skeletal muscle catabolism by favoring protein breakdown over synthesis. Ghrelin is a gastric hormone discovered and initially studied in its acylated orexigenic form. More recently, a role of unacylated ghrelin (UnAG) has been described to reduce skeletal muscle mitochondrial reactive oxygen species generation, inflammation, and insulin resistance both in experimental models and in clinical studies. UnAG administration could therefore represent a potential comprehensive therapeutic approach for CKD-related metabolic and nutritional complications. Studies of UnAG administration in experimental and clinical CKD are needed to test the hypothesis that UnAG may chronically improve nutritional status and outcome in CKD patients.

Procalcitonin in early rule-in/rule-out of sepsis in SIRS patients admitted to a medical ward.

BACKGROUND: A relevant amount of patients with clinical suspect of sepsis is admitted and treated in medical wards (MW). These patients have a better prognosis but are older and with more comorbidities compared to those admitted to intensive care units (ICU). Procalcitonin (PCT) is extensively used in emergency departments for the diagnosis of sepsis, but its accuracy in the setting of a MW has not been thoroughly investigated. Predicted low PCT levels also call for the comparison of immunomagnetic-chemiluminescent (L-PCT) and time-resolved amplified cryptate emission (TRACE, K-PCT) technologies, in PCT determination. METHODS: In 80 patients with systemic inflammatory response syndrome (SIRS) diagnostic criteria and suspect of sepsis newly admitted to a MW, PCT was determined with L- and K-PCT method. RESULTS: Sixty patients were diagnosed as sepsis (20 microbiologically and 40 clinically proven) and 20 with non-infective SIRS. The sepsis group had significantly higher levels of both PCTs, with no differences between the clinically and microbiologically proven subgroups. The areas under ROC curves for L- and K-PCT were 0.72 and 0.78 (p<0.001 for each), respectively. Based on MW customized cut-off values of 0.150 (L-PCT) and 0.143 ng/mL (K-PCT), overall accuracies were 66.8 (95% CI 58.7-78.9) and 78.2% (69.8-87.2), respectively, compared to the 55% (44.2-66) of 0.5 ng/mL canonical cut-off. Neither PCT-L nor -K held prognostic value on survival. CONCLUSIONS: In MW patients, customized PCT cut-off levels provide better accuracy than customary levels adopted from ICU, and TRACE technology seems to offer a wider analysis range.

Metabolic Consequences of Anabolic Steroids, Insulin, and Growth Hormone Abuse in Recreational Bodybuilders: Implications for the World Anti-Doping Agency Passport.

BACKGROUND: Hormonal doping in recreational sports is a public-health concern. The World Anti-Doping Agency (WADA) promoted the creation of the Athlete Biological Passport, aiming to monitor athlete's biological variables over time to facilitate indirect detection of doping. Detection tests for anabolic androgenic steroids (AAS) and growth hormone (GH) are available while insulin abuse cannot be revealed. We have determined in recreational bodybuilders the metabolic effects associated with different patterns of hormone abuse. All analyses were conducted using Statistical Package for Social Sciences (SPSS) 21.0 software (SPSS Chicago, IL). RESULTS: We have assessed plasma concentrations of selected metabolic markers and fatty acid content in erythrocyte membranes of 92 male bodybuilders and in 45 healthy controls. Hormonal abuse was identified by anonymous questionnaires. 43% (%) of recruited bodybuilders regularly abused hormones, i.e., anabolic androgenic steroids (95%) often associated with GH (30%) and/or insulin (38%). HDL-cholesterol was lower in insulin and/or GH abusers. Alanine (ALT) and aspartic (AST) transaminases were greater in hormone abusing bodybuilders than in non-doping bodybuilders and controls. Insulin doping was selectively associated with increased plasma ALT-to-AST ratio. In erythrocyte membranes, elongase activity (i.e., stearic-to-palmitic ratio) was lower in insulin and/or growth hormone doping, whereas increased Δ-9 desaturase activity (i.e., palmitoleic-to-palmitic ratio) was selectively associated with insulin doping. CONCLUSIONS: In conclusion, our study demonstrates that insulin and GH abuse are characterized by multiple alterations of specific metabolic markers. Although further studies are needed to test whether longitudinal monitoring of selected metabolic marker such as muscle contraction time, HDL levels, ALT-AST ratio as well as the activities of selected enzymes (e.g. Δ-9 desaturase and elongase), could contribute to the detection of insulin and GH abuse in sport.

Obesity and high waist circumference are associated with low circulating pentraxin-3 in acute coronary syndrome.

BACKGROUND: Long pentraxin 3 (PTX3) is a component of the pentraxin superfamily and a potential marker of vascular damage and inflammation, associated with negative outcome in patients with acute coronary syndromes (ACS). Obesity is a risk factor for cardiovascular disease and PTX3 production is reported in abdominal adipose tissue. Low PTX3 is however reported in the obese population, and obesity per se may be associated with less negative ACS outcome. METHODS: We investigated the potential impact of obesity and high waist circumference (reflecting abdominal fat accumulation) on plasma PTX3 concentration in ACS patients (n = 72, 20 obese) compared to age-, sex- and BMI-matched non-ACS individuals. RESULTS: Both obese and non-obese ACS patients had higher PTX3 than matched non-ACS counterparts, but PTX3 was lower in obese than non-obese individuals in both groups (all P < 0.05). PTX3 was also lower in ACS subjects with high than in those with normal waist circumference (WC). Plasma PTX3 was accordingly associated negatively with BMI and WC, independently of age and plasma creatinine. No associations were observed between PTX3 and plasma insulin, glucose or the short pentraxin and validated inflammation marker C-reactive protein, that was higher in ACS than in non-ACS individuals independently of BMI or WC. CONCLUSIONS: Obesity is associated with low circulating PTX3 in ACS. This association is also observed in the presence of abdominal fat accumulation as reflected by elevated waist circumference. Low PTX3 is a novel potential modulator of tissue damage and outcome in obese ACS patients.

High-protein diet with excess leucine prevents inactivity-induced insulin resistance in women.

BACKGROUND AND AIMS: Muscle inactivity leads to muscle atrophy and insulin resistance. The branched-chain amino acid (BCAA) leucine interacts with the insulin signaling pathway to modulate glucose metabolism. We have tested the ability of a high-protein BCAA-enriched diet to prevent insulin resistance during long-term bed rest (BR). METHODS: Stable isotopes were infused to determine glucose and protein kinetics in the postabsorptive state and during a hyperinsulinemic-euglycemic clamp in combination with amino acid infusion (Clamp + AA) before and at the end of 60 days of BR in two groups of healthy, young women receiving eucaloric diets containing 1 g of protein/kg per day (n = 8) or 1.45 g of protein/kg per day enriched with 0.15 g/kg per day of BCAAs (leucine/valine/isoleucine = 2/1/1) (n = 8). Body composition was determined by Dual X-ray Absorptiometry. RESULTS: BR decreased lean body mass by 7.6 ± 0.3 % and 7.2 ± 0.8 % in the groups receiving conventional or high protein-BCAA diets, respectively. Fat mass was unchanged in both groups. At the end of BR, percent changes of insulin-mediated glucose uptake significantly (p = 0.01) decreased in the conventional diet group from 155 ± 23 % to 84 ± 10 % while did not change significantly in the high protein-BCAA diet group from 126 ± 20 % to 141 ± 27 % (BR effect, p = 0.32; BR/diet interaction, p = 0.01; Repeated Measures ANCOVA). In contrast, there were no BR/diet interactions on proteolysis and protein synthesis Clamp + AA changes in the conventional diet and the high protein-BCAA diet groups. CONCLUSION: A high protein-BCAA enriched diet prevented inactivity-induced insulin resistance in healthy women.

Sarcopenic obesity in free-living older adults detected by the ESPEN-EASO consensus diagnostic algorithm: Validation in an Italian cohort and predictive value of insulin resistance and altered plasma ghrelin profile.

Aging and obesity are synergistic sarcopenia risk factors (RF). Their association in sarcopenic obesity (SO) enhances morbidity and mortality, but consensus on SO diagnostic criteria is limited. ESPEN and EASO issued a consensus algorithm for SO screening (obesity and clinical SO suspicion) and diagnosis [low muscle strength by hand-grip (HGS) and low muscle mass by BIA], and we investigated its implementation in older adults (>65-years), as well as SO-associated metabolic RF [insulin resistance (IR: HOMA) and plasma acylated (AG) and unacylated (UnAG) ghrelin, with predictive value also assessed from 5-year-prior observations]. Older adults with obesity from the Italian MoMa study on metabolic syndrome in primary care (n = 76) were studied. 7 of 61 individuals with positive screening had SO (SO+; 9 % of cohort). No individuals with negative screening had SO. SO+ had higher IR, AG and plasma AG/UnAG ratio (p < 0.05 vs negative screening and SO-), and both IR and ghrelin profile predicted 5-year SO risk independent of age, sex and BMI. The current results provide the first ESPEN-EASO algorithm-based investigation of SO in free-living older adults, with 9 % prevalence in those with obesity and 100 % algorithm sensitivity, and they support IR and plasma ghrelin profile as SO risk factors in this setting.

Lipoprotein(a) as a Risk Factor for Cardiovascular Diseases: Pathophysiology and Treatment Perspectives.

Cardiovascular disease (CVD) is still a leading cause of morbidity and mortality, despite all the progress achieved as regards to both prevention and treatment. Having high levels of lipoprotein(a) [Lp(a)] is a risk factor for cardiovascular disease that operates independently. It can increase the risk of developing cardiovascular disease even when LDL cholesterol (LDL-C) levels are within the recommended range, which is referred to as residual cardiovascular risk. Lp(a) is an LDL-like particle present in human plasma, in which a large plasminogen-like glycoprotein, apolipoprotein(a) [Apo(a)], is covalently bound to Apo B100 via one disulfide bridge. Apo(a) contains one plasminogen-like kringle V structure, a variable number of plasminogen-like kringle IV structures (types 1-10), and one inactive protease region. There is a large inter-individual variation of plasma concentrations of Lp(a), mainly ascribable to genetic variants in the Lp(a) gene: in the general po-pulation, Lp(a) levels can range from <1 mg/dL to >1000 mg/dL. Concentrations also vary between different ethnicities. Lp(a) has been established as one of the risk factors that play an important role in the development of atherosclerotic plaque. Indeed, high concentrations of Lp(a) have been related to a greater risk of ischemic CVD, aortic valve stenosis, and heart failure. The threshold value has been set at 50 mg/dL, but the risk may increase already at levels above 30 mg/dL. Although there is a well-established and strong link between high Lp(a) levels and coronary as well as cerebrovascular disease, the evidence regarding incident peripheral arterial disease and carotid atherosclerosis is not as conclusive. Because lifestyle changes and standard lipid-lowering treatments, such as statins, niacin, and cholesteryl ester transfer protein inhibitors, are not highly effective in reducing Lp(a) levels, there is increased interest in developing new drugs that can address this issue. PCSK9 inhibitors seem to be capable of reducing Lp(a) levels by 25-30%. Mipomersen decreases Lp(a) levels by 25-40%, but its use is burdened with important side effects. At the current time, the most effective and tolerated treatment for patients with a high Lp(a) plasma level is apheresis, while antisense oligonucleotides, small interfering RNAs, and microRNAs, which reduce Lp(a) levels by targeting RNA molecules and regulating gene expression as well as protein production levels, are the most widely explored and promising perspectives. The aim of this review is to provide an update on the current state of the art with regard to Lp(a) pathophysiological mechanisms, focusing on the most effective strategies for lowering Lp(a), including new emerging alternative therapies. The purpose of this manuscript is to improve the management of hyperlipoproteinemia(a) in order to achieve better control of the residual cardiovascular risk, which remains unacceptably high.

Epidemiology of atherosclerotic cardiovascular disease in polygenic hypercholesterolemia with or without high lipoprotein(a) levels.

Background and aims: Epidemiology of atherosclerotic cardiovascular disease might be different in patients with polygenic hypercholesterolemia plus high levels (≥30 mg/dl) of Lp(a) (H-Lpa) than in those with polygenic hypercholesterolemia alone (H-LDL). We compared the incidence of peripheral artery disease (PAD), coronary artery disease (CAD), and cerebrovascular disease (CVD) in patients with H-Lpa and in those with H-LDL. Methods: Retrospective analysis of demographics, risk factors, vascular events, therapy, and lipid profile in outpatient clinical data. Inclusion criteria was adult age, diagnosis of polygenic hypercholesterolemia, and both indication and availability for Lp(a) measurement. Results: Medical records of 258 patients with H-Lpa and 290 H-LDL were reviewed for occurrence of vascular events. The median duration of follow-up was 10 years (IQR 3-16). In spite of a similar reduction of LDL cholesterol, vascular events occurred more frequently, and approximately 7 years earlier (P = 0.024) in patients with H-Lpa than in H-LDL (HR 1.96 1.21-3.17, P = 0.006). The difference was around 10 years for acute events (TIA, Stroke, acute coronary events) and one year for chronic ones (P = 0.023 and 0.525, respectively). Occurrence of acute CAD was higher in H-Lpa men (HR 3.1, 95% CI 1.2-7.9, P = 0.007) while, among women, PAD was observed exclusively in H-Lpa subjects with smoking habits (P = 0.009). Conclusions: Patients with high Lp(a) levels suffer from a larger and earlier burden of the disease compared to those with polygenic hypercholesterolemia alone. These patients are at higher risk of CAD if they are men, and of PAD if they are women.

[Identifying possible homozygous familial hypercholesterolemia patients: an Italian experts' opinion]. / Inquadramento diagnostico del paziente con possibile ipercolesterolemia familiare omozigote: il parere di un gruppo italiano di esperti.

Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disease characterized by high plasma levels of low-density lipoprotein cholesterol (LDL-C) and massive risk of premature atheromasia and cardiovascular events. HoFH is caused by mutations in several genes, such as LDLR, APOB, PCSK9 and LDLRAP1. If untreated, the average age of death is 18 years old, but fatalities within the first 5 years of age have been recorded. Therefore, early diagnosis and treatment are crucial, in order to prevent and/or delay the cardiovascular complications of LDL-C exposure. Because HoFH is a rare disorder, it is not frequently encountered in daily clinical practice at the primary/secondary unspecialized cardiological centers. Then the availability of practical indications helping to identify HoFH patients or to arise a suspect of HoFH is particularly strategic to promptly start the appropriate lipid-lowering therapy. For such a purpose, a group of Italian experts suggests three useful algorithms to identify cases requiring accurate and specialized clinical evaluation as potential HoFH patients. These cases with suspected HoFH should be addressed to specialized centres for the optimal management of these patients.

Skeletal Muscle in Hypoxia and Inflammation: Insights on the COVID-19 Pandemic.

SARS-CoV-2 infection is often associated with severe inflammation, oxidative stress, hypoxia and impaired physical activity. These factors all together contribute to muscle wasting and fatigue. In addition, there is evidence of a direct SARS-CoV-2 viral infiltration into skeletal muscle. Aging is often characterized by sarcopenia or sarcopenic obesity These conditions are risk factors for severe acute COVID-19 and long-COVID-19 syndrome. From these observations we may predict a strong association between COVID-19 and decreased muscle mass and functions. While the relationship between physical inactivity, chronic inflammation, oxidative stress and muscle dysfunction is well-known, the effects on muscle mass of COVID-19-related hypoxemia are inadequately investigated. The aim of this review is to highlight metabolic, immunity-related and redox biomarkers potentially affected by reduced oxygen availability and/or muscle fatigue in order to shed light on the negative impact of COVID-19 on muscle mass and function. Possible countermeasures are also reviewed.

Mechanism of action and therapeutic use of bempedoic acid in atherosclerosis and metabolic syndrome.

Bempedoic acid is a new cholesterol-lowering drug, which has recently received US FDA and EMA approval. This drug targets lipid and glucose metabolism as well as inflammation via downregulation of ATP-citrate lyase and upregulation of AMP-activated protein kinase (AMPK). The primary effect is the reduction of cholesterol synthesis in the liver and its administration is generally not associated to unwanted muscle effects. Suppression of hepatic fatty acid synthesis leads to decreased triglycerides and, possibly, improved non-alcoholic fatty liver disease. Bempedoic acid may decrease gluconeogenesis leading to improved insulin sensitivity, glucose metabolism, and metabolic syndrome. The anti-inflammatory action of bempedoic acid is mainly achieved via activation of AMPK pathway in the immune cells, leading to decreased plasma levels of C-reactive protein. Effects of bempedoic acid on atherosclerotic cardiovascular disease, type 2 diabetes and chronic liver disease have been assessed in randomized clinical trials but require further confirmation. Safety clinical trials in phase III indicate that bempedoic acid administration is generally well-tolerated in combination with statins, ezetimibe, or proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors to achieve low-density lipoprotein cholesterol targets. The aim of this narrative review on bempedoic acid is to explore the underlying mechanisms of action and potential clinical targets, present existing evidence from clinical trials, and describe practical management of patients.

Early lean mass sparing effect of high-protein diet with excess leucine during long-term bed rest in women.

Muscle inactivity leads to muscle atrophy. Leucine is known to inhibit protein degradation and to promote protein synthesis in skeletal muscle. We tested the ability of a high-protein diet enriched with branched-chain amino acids (BCAAs) to prevent muscle atrophy during long-term bed rest (BR). We determined body composition (using dual energy x-ray absorptiometry) at baseline and every 2-weeks during 60 days of BR in 16 healthy young women. Nitrogen (N) balance was assessed daily as the difference between N intake and N urinary excretion. The subjects were randomized into two groups: one received a conventional diet (1.1 ± 0.03 g protein/kg, 4.9 ± 0.3 g leucine per day) and the other a high protein, BCAA-enriched regimen (1.6 ± 0.03 g protein-amino acid/kg, 11.4 ± 0.6 g leucine per day). There were significant BR and BR × diet interaction effects on changes in lean body mass (LBM) and N balance throughout the experimental period (repeated measures ANCOVA). During the first 15 days of BR, lean mass decreased by 4.1 ± 0.9 and 2.4 ± 2.1% (p < 0.05) in the conventional and high protein-BCAA diet groups, respectively, while at the end of the 60-day BR, LBM decreased similarly in the two groups by 7.4 ± 0.7 and 6.8 ± 2.4%. During the first 15 days of BR, mean N balance was 2.5 times greater (p < 0.05) in subjects on the high protein-BCAA diet than in those on the conventional diet, while we did not find significant differences during the following time intervals. In conclusion, during 60 days of BR in females, a high protein-BCAA diet was associated with an early protein-LBM sparing effect, which ceased in the medium and long term.

n-3 PUFA dietary lipid replacement normalizes muscle mitochondrial function and oxidative stress through enhanced tissue mitophagy and protects from muscle wasting in experimental kidney disease.

INTRODUCTION AND METHODS: Skeletal muscle mitochondrial dysfunction may cause tissue oxidative stress and consequent catabolism in chronic kidney disease (CKD), contributing to patient mortality. We investigated in 5/6-nephrectomized (Nx) rats the impact of n3-polyunsaturated fatty-acids (n3-PUFA) isocaloric partial dietary replacement on gastrocnemius muscle (Gm) mitochondrial master-regulators, ATP production, ROS generation and related muscle-catabolic derangements. RESULTS: Nx had low Gm mitochondrial nuclear respiratory factor-2 and peroxisome proliferator-activated receptor gamma coactivator-1alpha, low ATP production and higher mitochondrial fission-fusion protein ratio with ROS overproduction. n3-PUFA normalized all mitochondrial derangements and pro-oxidative tissue redox state (oxydized to total glutathione ratio). n3-PUFA also normalized Nx-induced muscle-catabolic proinflammatory cytokines, insulin resistance and low muscle weight. Human uremic serum reproduced mitochondrial derangements in C2C12 myotubes, while n3-PUFA coincubation prevented all effects. n3-PUFA also enhanced muscle mitophagy in-vivo and siRNA-mediated autophagy inhibition selectively blocked n3-PUFA-induced normalization of C2C12 mitochondrial ROS production. CONCLUSIONS: In conclusion, dietary n3-PUFA normalize mitochondrial master-regulators, ATP production and dynamics in experimental CKD. These effects occur directly in muscle cells and they normalize ROS production through enhanced mitophagy. Dietary n3-PUFA mitochondrial effects result in normalized catabolic derangements and protection from muscle wasting, with potential positive impact on patient survival.

The Aging Muscle in Experimental Bed Rest: A Systematic Review and Meta-Analysis.

Background: Maintaining skeletal muscle mass and function in aging is crucial for preserving the quality of life and health. An experimental bed rest (BR) protocol is a suitable model to explore muscle decline on aging during inactivity. Objective: The purpose of this systematic review and meta-analysis was, therefore, to carry out an up-to-date evaluation of bed rest, with a specific focus on the magnitude of effects on muscle mass, strength, power, and functional capacity changes as well as the mechanisms, molecules, and pathways involved in muscle decay. Design: This was a systematic review and meta-analysis study. Data sources: We used PubMed, Medline; Web of Science, Google Scholar, and the Cochrane library, all of which were searched prior to April 23, 2020. A manual search was performed to cover bed rest experimental protocols using the following key terms, either singly or in combination: "Elderly Bed rest," "Older Bed rest," "Old Bed rest," "Aging Bed rest," "Aging Bed rest," "Bed-rest," and "Bedrest". Eligibility criteria for selecting studies: The inclusion criteria were divided into four sections: type of study, participants, interventions, and outcome measures. The primary outcome measures were: body mass index, fat mass, fat-free mass, leg lean mass, cross-sectional area, knee extension power, cytokine pattern, IGF signaling biomarkers, FOXO signaling biomarkers, mitochondrial modulation biomarkers, and muscle protein kinetics biomarkers. Results: A total of 25 studies were included in the qualitative synthesis, while 17 of them were included in the meta-analysis. In total, 118 healthy elderly volunteers underwent 5-, 7-, 10-, or 14-days of BR and provided a brief sketch on the possible mechanisms involved. In the very early phase of BR, important changes occurred in the skeletal muscle, with significant loss of performance associated with a lesser grade reduction of the total body and muscle mass. Meta-analysis of the effect of bed rest on total body mass was determined to be small but statistically significant (ES = -0.45, 95% CI: -0.72 to -0.19, P < 0.001). Moderate, statistically significant effects were observed for total lean body mass (ES = -0.67, 95% CI: -0.95 to -0.40, P < 0.001) after bed rest intervention. Overall, total lean body mass was decreased by 1.5 kg, while there was no relationship between bed rest duration and outcomes (Z = 0.423, p = 672). The meta-analyzed effect showed that bed rest produced large, statistically significant, effects (ES = -1.06, 95% CI: -1.37 to -0.75, P < 0.001) in terms of the knee extension power. Knee extension power was decreased by 14.65 N/s. In contrast, to other measures, meta-regression showed a significant relationship between bed rest duration and knee extension power (Z = 4.219, p < 0.001). Moderate, statistically significant, effects were observed after bed rest intervention for leg muscle mass in both old (ES = -0.68, 95% CI: -0.96 to -0.40, P < 0.001) and young (ES = -0.51, 95% CI: -0.80 to -0.22, P < 0.001) adults. However, the magnitude of change was higher in older (MD = -0.86 kg) compared to younger (MD = -0.24 kg) adults. Conclusion: Experimental BR is a suitable model to explore the detrimental effects of inactivity in young adults, old adults, and hospitalized people. Changes in muscle mass and function are the two most investigated variables, and they allow for a consistent trend in the BR-induced changes. Mechanisms underlying the greater loss of muscle mass and function in aging, following inactivity, need to be thoroughly investigated.

Ruling Out Coronavirus Disease 2019 in Patients with Pneumonia: The Role of Blood Cell Count and Lung Ultrasound.

Coronavirus disease 2019 (COVID-19) is characterized by a distinctive blood leucocyte pattern and B-lines on lung ultrasound (LUS) as marker of alveolar-interstitial syndrome. We aimed to evaluate the accuracy of blood leucocyte count alone or in combination with LUS for COVID-19 diagnosis. We retrospectively enrolled consecutive patients diagnosed with community acquired pneumonia (CAP) at hospital admission to derive and validate cutoff values for blood cell count that could be predictive of COVID-19 before confirmation by the nucleic acid amplification test (NAAT). Cutoff values, generated and confirmed in inception (41/115, positive/negative patients) and validation (100/180, positive/negative patients) cohorts, were ≤17 and ≤10 cells/mm3 for basophils and eosinophils, respectively. Basophils and/or eosinophils below cutoff were associated with sensitivity of 98% (95%CI, 94-100) and negative likelihood ratio of 0.04 (95%CI, 0.01-0.11). In a subgroup of 265 subjects, the sensitivity of B-line on LUS was 15% lower (p < 0.001) than that of basophils and/or eosinophils below cutoff. The combination of B-lines with basophils and eosinophils below cutoff was associated with a moderate increase of the positive likelihood ratio: 5.0 (95%CI, 3.2-7.7). In conclusion, basophil and eosinophil counts above the generated cutoff virtually rule out COVID-19 in patients with CAP. Our findings can help optimize patient triage pending the NAAT results.

Metabolic syndrome and chronic kidney disease.

Obesity is a global health threat because of its associated metabolic and cardiovascular complications. Metabolic and hemodynamic complications of obesity (insulin resistance and hyperglycemia, hypertension, atherogenic dyslipidemia) are often clustered in the metabolic syndrome, leading to high cardiovascular morbidity and mortality. In recent years, epidemiological studies have clearly indicated that both obesity and the metabolic syndrome are independent risk factors for chronic kidney disease and these associations are at least in part independent of diabetes and hypertension per se. Additional mechanisms associated with obesity and metabolic syndrome leading to reduced renal function may include altered levels of adipose tissue hormones, inflammation, and oxidative stress. The ongoing worldwide obesity epidemic is therefore likely to increase the number of patients with chronic uremia and features of the metabolic syndrome in the next few years. Moreover, the onset and maintenance of renal damage may worsen metabolic syndrome features including insulin resistance and hypertension, leading to potential vicious cycles with negative clinical effect. Further understanding of the interactions between obesity, metabolic syndrome, and chronic kidney disease represents a potential strategy to design more effective treatments aimed at reducing morbidity and mortality in uremic patients.

Insulin resistance in chronic uremia.

Insulin resistance often characterizes chronic uremia, and is associated with enhanced morbidity and mortality, because it may contribute to protein-energy wasting (in turn, an independent predictor of reduced survival), atherosclerosis, and cardiovascular death. Causes of insulin resistance in chronic uremia are complex and multifactorial. Obesity is emerging as an independent risk factor for chronic kidney disease, and an expected rise in number of obese uremic patients because of the ongoing worldwide obesity epidemic is likely to increase the prevalence of insulin resistance in chronic uremia in the near future. Similar to the general population, reported associations between obesity and insulin resistance in chronic uremia support a role of adipose tissue and altered adipokine profiles in insulin resistance in obese chronic kidney disease patients. Hormonal imbalances, chronic acidosis, and systemic inflammation and oxidative stress are uremia-associated relevant causes of insulin resistance in nonobese individuals. A further understanding of the causes of insulin resistance in chronic uremia represents a potential important tool in the design of more effective therapeutic strategies to reduce uremia-associated morbidity and mortality.

Central adiposity markers, plasma lipid profile and cardiometabolic risk prediction in overweight-obese individuals.

BACKGROUND: Waist circumference (WC) is the currently recommended marker of central fat for cardiometabolic risk screening. Alternative surrogate markers have been recently proposed to better reflect the metabolic impact of central fat accumulation per se, based on WC normalization by height (Weight-to-Height Ratio - WtoH; Body Roundness Index - BRI) or body mass index (BMI) without (A Body Shape Index - ABSI) or with inclusion of plasma triglyceride and HDL-cholesterol concentrations (Visceral Adiposity Index - VAI). METHODS: We investigated associations between WtoH, BRI, ABSI or VAI and insulin resistance (HOMA-index) or metabolic syndrome (MetS) in a general population cohort from the North-East Italy Mo.Ma. study (n = 1965, age = 49 ± 13 years, BMI = 26.7 ± 5.2 kg/m2). Baseline values were also evaluated as predictors of future insulin resistance and MetS in overweight-obese individuals undergoing 5-year follow-up (Ow-Ob) (n = 263; age = 54 ± 9, BMI = 30,7 ± 4,1). RESULTS: Compared to WC or BMI, basal WtoH and BRI were similarly associated with baseline HOMA and MetS prevalence after multiple adjustments (P < 0.001) and all markers similarly predicted 5-year HOMA and MetS (P < 0.001). Under basal conditions, superimposable results were observed for VAI whereas ABSI was less accurate or unable to identify baseline HOMA and MetS (p < 0.05 vs WtoH-BRI-VAI-WC-BMI). VAI had highest 5-year risk predictive value in Ow-Ob [ROC Area Under the Curve (AUC) VAI > WtoH-BRI-WC-BMI; p < 0.05] while no predictive value was in contrast observed for ABSI (ROC AUC ABSI < WtoH-BRI-WC-BMI; p < 0.05). Using alternate formulae with plasma lipid inclusion in ABSI and removal from VAI calculations completely reversed their 5-year predictive value and AUC. CONCLUSIONS: The current findings do not support replacement of WC with height-normalized anthropometric central fat surrogate markers to predict cardiometabolic risk in the general and overweight-obese population. BMI-normalization impairs risk assessment unless plasma lipid concentrations are available and included in calculations.