n-3 PUFA-Enriched Diet Preserves Skeletal Muscle Mitochondrial Function and Redox State and Prevents Muscle Mass Loss in Mice with Chronic Heart Failure.

Rationale and Methods: Skeletal muscle derangements, potentially including mitochondrial dysfunction with altered mitochondrial dynamics and high reactive oxygen species (ROS) generation, may lead to protein catabolism and muscle wasting, resulting in low exercise capacity and reduced survival in chronic heart failure (CHF). We hypothesized that 8-week n-3-PUFA isocaloric partial dietary replacement (Fat = 5.5% total cal; EPA + DHA = 27% total fat) normalizes gastrocnemius muscle (GM) mitochondrial dynamics regulators, mitochondrial and tissue pro-oxidative changes, and catabolic derangements, resulting in preserved GM mass in rodent CHF [Myocardial infarction (MI)-induced CHF by coronary artery ligation, left-ventricular ejection fraction <50%]. Results: Compared to control animals (Sham), CHF had a higher GM mitochondrial fission-fusion protein ratio, with low ATP and high ROS production, pro-inflammatory changes, and low insulin signalling. n-3-PUFA normalized all mitochondrial derangements and the pro-oxidative state (oxidized to total glutathione ratio), associated with normalized GM cytokine profile, and enhanced muscle-anabolic insulin signalling and prevention of CHF-induced GM weight loss (all p < 0.05 vs. CHF and p = NS vs. S). Conclusions:n-3-PUFA isocaloric partial dietary replacement for 8 weeks normalizes CHF-induced derangements of muscle mitochondrial dynamics regulators, ROS production and function. n-3-PUFA mitochondrial effects result in preserved skeletal muscle mass, with potential to improve major patient outcomes in clinical settings.

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.

Clinical Nutrition and Human Rights. An International Position Paper.

The International Working Group for Patients' Right to Nutritional Care presents its position paper regarding nutritional care as a human right intrinsically linked to the right to food and the right to health. All people should have access to food and evidence-based medical nutrition therapy including artificial nutrition and hydration. In this regard, the hospitalized malnourished ill should mandatorily have access to screening, diagnosis, nutritional assessment, with optimal and timely nutritional therapy in order to overcome malnutrition associated morbidity and mortality, while reducing the rates of disease-related malnutrition. This right does not imply there is an obligation to feed all patients at any stage of life and at any cost. On the contrary, this right implies, from an ethical point of view, that the best decision for the patient must be taken and this may include, under certain circumstances, the decision not to feed. Application of the human rights-based approach to the field of clinical nutrition will contribute to the construction of a moral, political, and legal focus to the concept of nutritional care. Moreover, it will be the cornerstone to the rationale of political and legal instruments in the field of clinical nutrition.

Clinical nutrition and human rights. An international position paper.

The International Working Group for Patients' Right to Nutritional Care presents its position paper regarding nutritional care as a human right intrinsically linked to the right to food and the right to health. All people should have access to food and evidence-based medical nutrition therapy including artificial nutrition and hydration. In this regard, the hospitalized malnourished ill should mandatorily have access to screening, diagnosis, nutritional assessment, with optimal and timely nutritional therapy in order to overcome malnutrition associated morbidity and mortality, while reducing the rates of disease-related malnutrition. This right does not imply there is an obligation to feed all patients at any stage of life and at any cost. On the contrary, this right implies, from an ethical point of view, that the best decision for the patient must be taken and this may include, under certain circumstances, the decision not to feed. Application of the human rights-based approach to the field of clinical nutrition will contribute to the construction of a moral, political and legal focus to the concept of nutritional care. Moreover, it will be the cornerstone to the rationale of political and legal instruments in the field of clinical nutrition.

The Impact of Protein Supplementation Targeted at Improving Muscle Mass on Strength in Cancer Patients: A Scoping Review.

Deterioration of muscle strength during cancer results in functional limitation, poor quality of life and reduced survival. The indirect effects on muscle strength of nutritional interventions based on protein and amino acid derivatives targeted at improving muscle mass are poorly documented. A scoping review was performed to examine the available evidence on the effects of proteins, amino acids and their derivatives on muscle strength in adult cancer patients. Pubmed and Scopus databases were searched to identify research articles published in the last 10 years. Fourteen studies met the inclusion criteria, showing that changes in muscle strength following protein or amino acid supplementation are generally concordant with those in muscle mass in cancer patients. Administration of both energy and proteins in the presence of reduced oral intakes results in more robust effects on both muscle strength and mass. It is not clear whether this is due to the correction of the energy deficit or to an interaction between proteins and other macronutrients. The optimal mixture, type, and dose of amino acid/protein supplementation alone or in combination with other anabolic strategies should be determined to provide the best nutritional approach in cancer.

Perioperative nutrition: Recommendations from the ESPEN expert group.

BACKGROUND & AIMS: Malnutrition has been recognized as a major risk factor for adverse postoperative outcomes. The ESPEN Symposium on perioperative nutrition was held in Nottingham, UK, on 14-15 October 2018 and the aims of this document were to highlight the scientific basis for the nutritional and metabolic management of surgical patients. METHODS: This paper represents the opinion of experts in this multidisciplinary field and those of a patient and caregiver, based on current evidence. It highlights the current state of the art. RESULTS: Surgical patients may present with varying degrees of malnutrition, sarcopenia, cachexia, obesity and myosteatosis. Preoperative optimization can help improve outcomes. Perioperative fluid therapy should aim at keeping the patient in as near zero fluid and electrolyte balance as possible. Similarly, glycemic control is especially important in those patients with poorly controlled diabetes, with a stepwise increase in the risk of infectious complications and mortality per increasing HbA1c. Immobilization can induce a decline in basal energy expenditure, reduced insulin sensitivity, anabolic resistance to protein nutrition and muscle strength, all of which impair clinical outcomes. There is a role for pharmaconutrition, pre-, pro- and syn-biotics, with the evidence being stronger in those undergoing surgery for gastrointestinal cancer. CONCLUSIONS: Nutritional assessment of the surgical patient together with the appropriate interventions to restore the energy deficit, avoid weight loss, preserve the gut microbiome and improve functional performance are all necessary components of the nutritional, metabolic and functional conditioning of the surgical patient.

ESPEN expert statements and practical guidance for nutritional management of individuals with SARS-CoV-2 infection.

The COVID-19 pandemics is posing unprecedented challenges and threats to patients and healthcare systems worldwide. Acute respiratory complications that require intensive care unit (ICU) management are a major cause of morbidity and mortality in COVID-19 patients. Patients with worst outcomes and higher mortality are reported to include immunocompromised subjects, namely older adults and polymorbid individuals and malnourished people in general. ICU stay, polymorbidity and older age are all commonly associated with high risk for malnutrition, representing per se a relevant risk factor for higher morbidity and mortality in chronic and acute disease. Also importantly, prolonged ICU stays are reported to be required for COVID-19 patients stabilization, and longer ICU stay may per se directly worsen or cause malnutrition, with severe loss of skeletal muscle mass and function which may lead to disability, poor quality of life and additional morbidity. Prevention, diagnosis and treatment of malnutrition should therefore be routinely included in the management of COVID-19 patients. In the current document, the European Society for Clinical Nutrition and Metabolism (ESPEN) aims at providing concise guidance for nutritional management of COVID-19 patients by proposing 10 practical recommendations. The practical guidance is focused to those in the ICU setting or in the presence of older age and polymorbidity, which are independently associated with malnutrition and its negative impact on patient survival.

Sarcopenic obesity: Time to meet the challenge.

The prevalence of overweight and obesity has reached epidemic proportions worldwide due to increasingly pervasive obesogenic lifestyle changes. Obesity poses unprecedented individual, social and multi-disciplinary medical challenges by increasing the risk for metabolic diseases, chronic organ failures and cancer, as well as complication rates in the presence of acute disease conditions. Whereas reducing excess adiposity remains the fundamental pathogenetic treatment for obese individuals, complex metabolic and lifestyle abnormalities as well as weight-reduction therapies per se may also compromise the ability to preserve muscle function and mass, especially when chronic disease co-exists with obesity. Emerging evidence indicates that low muscle mass and quality have a strong negative prognostic impact in obese individuals and may lead to frailty, disability and increased morbidity and mortality. Awareness of the importance of skeletal muscle maintenance in obesity is however low among clinicians and scientists. The term "sarcopenic obesity" has been proposed to identify obesity with low skeletal muscle function and mass, but its utilization is largely limited to the aging patient population, and consensus on its definition and diagnostic criteria remains insufficient. Knowledge on prevalence of sarcopenic obesity in various clinical conditions and patient subgroups, on its clinical impacts in patient risk stratification and on effective prevention and treatment strategies remain therefore dramatically inadequate. In particular, optimal dietary options and medical nutritional support strategies to preserve muscle mass in obese individuals remain largely undefined. The European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO) recognize and indicate obesity with altered body composition due to low skeletal muscle function and mass (sarcopenic obesity) as a scientific and clinical priority for researchers and clinicians. ESPEN and EASO therefore call for coordinated action aimed at reaching consensus on its definition, diagnostic criteria and optimal treatment with particular regard to nutritional therapy. We are convinced that achievement of these goals has strong potential to reduce the burden of morbidity and mortality in the rapidly increasing obese patient population.

Update on the Impact of Omega 3 Fatty Acids on Inflammation, Insulin Resistance and Sarcopenia: A Review.

Elderly and patients affected by chronic diseases face a high risk of muscle loss and impaired physical function. Omega 3 fatty acids (FA) attenuate inflammation and age-associated muscle loss, prevent systemic insulin resistance and improve plasma lipids, potentially impacting on sarcopenia. This paper aims to review recent randomized clinical studies assessing the effects a chronic omega 3 FA supplementation on inflammatory and metabolic profile during conditions characterized by sarcopenia (aging, insulin resistance, type 2 diabetes, chronic renal failure). A comprehensive search of three online databases was performed to identify eligible trials published between 2012 and 2017. A total of 36 studies met inclusion criteria. Omega 3 FA yielded mixed results on plasma triglycerides in the elderly and no effects in renal patients. No changes in systemic insulin resistance were observed. Inflammation markers did not benefit from omega 3 FA in insulin resistant and in renal subjects while decreasing in obese and elderly. Muscle related parameters improved in elderly and in renal patients. In conclusion, in aging- and in chronic disease-associated sarcopenia omega 3 FA are promising independently of associated anabolic stimuli or of anti-inflammatory effects. The evidence for improved glucose metabolism in insulin resistant and in chronic inflammatory states is less solid.

Omega 3 Polyunsaturated Fatty Acids Improve Endothelial Dysfunction in Chronic Renal Failure: Role of eNOS Activation and of Oxidative Stress.

BACKGROUND: Endothelial dysfunction is a key vascular alteration in chronic kidney disease (CKD). Omega 3 (n-3) polyunsaturated fatty acids (PUFA) reduce vascular oxidative stress and inflammation. We investigated whether n-3 PUFA could reverse endothelial dysfunction in CKD by improving endothelial nitric oxide synthase (eNOS) function and oxidative stress. METHODS: 5/6 nephrectomized male Wistar rats (CKD; n = 10) and sham operated animals (SHAM; n = 10) were treated for 6 weeks with standard diet. An additional group of CKD rats were fed an n-3 PUFA enriched diet (CKD + PUFA; n = 10). We then measured endothelium-dependent (EDD) and -independent vasodilation, markers of endothelial function and of oxidative stress in thoracic aortas. RESULTS: Compared to SHAM, in CKD aortas EDD and eNOS expression were reduced (p < 0.05) and 3-nitrotyrosine levels were increased, while expression of NADPH oxidase subunits NOX4 and p22phox was similar. In-vitro incubation with Tiron failed to reverse endothelial dysfunction in CKD. In CKD + PUFA, EDD improved (p < 0.05) compared with CKD rats, while blockade of eNOS by L-NAME worsened EDD. These effects were accompanied by increased (p < 0.05) eNOS and reduced (p < 0.05) expression of NOX4 and 3-nitrotyrosine levels. CONCLUSION: Collectively, these findings indicate that n-3 PUFA improve endothelial dysfunction by restoring NO bioavailability in CKD.

Health insurance or subsidy has universal advantage for management of hospital malnutrition unrelated to GDP.

BACKGROUND AND OBJECTIVES: Protein-energy and micronutrient malnutrition are global public health problems which, when not prevented and severe, require medical management by clinicians with nutrition expertise, preferably as a collectively skilled team, especially when disease-related. This study aimed to investigate barriers and facilitators of clinical nutrition services (CNS), especially the use of oral, enteral (EN) and parenteral (PN) nutrition in institutional and home settings. METHODS AND STUDY DESIGN: An international survey was performed between January and December 2014 in twenty-six countries from all continents. Electronic questionnaires were distributed to 28 representatives of clinical nutrition (PEN) societies, 27 of whom responded. The questionnaire comprised questions regarding a country's economy, reimbursement for CNS, education about and the use of EN and PN. RESULTS: The prevalence of malnutrition was not related to gross domestic product (GDP) at purchasing power parity (PPP) per capita (p=0.186). EN and PN were used in all countries surveyed (100%), but to different extents. Reimbursement of neither EN nor PN use depended on GDP, but was associated with increased use of EN and PN in hospitals (p=0.035), although not evident for home or chronic care facilities. The size of GDP did not affect the use of EN (p=0.256), but it mattered for PN (p=0.019). CONCLUSIONS: A worldwide survey by nutrition support societies did not find a link between national economic performance and the implementation of medical nutrition services. Reimbursement for CNS, available through health insurance systems, is a factor in effective nutrition management.

Effectiveness and efficacy of nutritional therapy: A systematic review following Cochrane methodology.

BACKGROUND & AIMS: Disease-related malnutrition has deleterious consequences on patients' outcome and healthcare costs. The demonstration of improved outcome by appropriate nutritional management is on occasion difficult. The European Society of Clinical Nutrition and Metabolism (ESPEN) appointed the Nutrition Education Study Group (ESPEN-NESG) to increase recognition of nutritional knowledge and support in health services. METHODS: To obtain the best available evidence on the potential effects of malnutrition on morbidity, mortality and hospital stay; cost of malnutrition; effect of nutritional treatment on outcome parameters and pharmaco-economics of nutritional therapy, a systematic review of the literature was performed following Cochrane methodology, to answer the following key questions: Q1) Is malnutrition an independent predictive factor for readmission within 30 days from hospital discharge? Q2) Does nutritional therapy reduce the risk of readmission within 30 days from hospital discharge? Q3) Is nutritional therapy cost-effective/does it reduce costs in hospitalized patients? and Q4) Is nutritional therapy cost effective/does it reduce costs in outpatients? RESULTS: For Q1 six of 15 identified observational studies indicated that malnutrition was predictive of re-admissions, whereas the remainder did not. For Q2 nine randomized controlled trials and two meta-analyses gave non-conclusive results whether re-admissions could be reduced by nutritional therapy. Economic benefit and cost-effectiveness of nutritional therapy was consistently reported in 16 identified studies for hospitalized patients (Q3), whereas the heterogeneous and limited corresponding data on out-patients (Q4) indicated cost-benefits in some selected sub-groups. CONCLUSIONS: This result of this review supports the use of nutritional therapy to reduce healthcare costs, most evident from large, homogeneous studies. In general, reports are too heterogeneous and overall of limited quality for conclusions on impact of malnutrition and its treatment on readmissions.

Omega-3 Polyunsaturated Fatty Acids: Structural and Functional Effects on the Vascular Wall.

Omega-3 polyunsaturated fatty acids (n-3 PUFA) consumption is associated with reduced cardiovascular disease risk. Increasing evidence demonstrating a beneficial effect of n-3 PUFA on arterial wall properties is progressively emerging. We reviewed the recent available evidence for the cardiovascular effects of n-3 PUFA focusing on structural and functional properties of the vascular wall. In experimental studies and clinical trials n-3 PUFA have shown the ability to improve arterial hemodynamics by reducing arterial stiffness, thus explaining some of its cardioprotective properties. Recent studies suggest beneficial effects of n-3 PUFA on endothelial activation, which are likely to improve vascular function. Several molecular, cellular, and physiological pathways influenced by n-3 PUFA can affect arterial wall properties and therefore interfere with the atherosclerotic process. Although the relative weight of different physiological and molecular mechanisms and the dose-response on arterial wall properties have yet to be determined, n-3 PUFA have the potential to beneficially impact arterial wall remodeling and cardiovascular outcomes by targeting arterial wall stiffening and endothelial dysfunction.

Biomarkers of fish oil omega-3 polyunsaturated fatty acids intake in humans.

A biomarker is a measured characteristic that may be used as an indicator of some biological state or condition. In health and disease, biomarkers have been used not only for clinical diagnosis purposes but also as tools to assess effectiveness of a nutrition or drug intervention. When considering nutrition studies, evaluating the appropriate biomarker is a useful tool to assess compliance and incidence of a particular dietary component in the biochemistry of the organism. Fish oil is rich in ω-3 fatty acids that have well-known beneficial effects on human health mainly through its anti-inflammatory properties. It has been widely use to improve health and as a nutrition supplement in different pathological conditions such as cardiovascular, neurological, and critically ill related diseases. Eicosapentaenoic acid and docosahexaenoic acid levels present in different biological moieties (plasma, cellular membranes, adipose tissue, etc) are the best biomarkers of fish oil intake. Each biological source of fatty acids has its own advantages and disadvantages, thus which biomarker to choose and where to measure it requires a comprehension of the objectives of the investigation. In this article we will review key facts about fish oil intake biomarkers to evaluate how components of a specific diet could be monitored and identified in biological samples. Having an accurate assessment of nutrition patterns could provide effective targets for intervention aimed at modifying eating habits and lifestyle towards the improvement of health.

Treatment with n-3 polyunsaturated fatty acids reverses endothelial dysfunction and oxidative stress in experimental menopause.

Menopause is associated with endothelial dysfunction and oxidative stress. In this condition, reduced n-3 polyunsaturated fatty acids (n-3 PUFAs) contribute to cardiovascular disease. We investigated whether treatment with n-3 PUFA reverses endothelial dysfunction and oxidative stress in experimental menopause. Thirty female rats underwent either sham-surgery or bilateral ovariectomy or bilateral ovariectomy+oral n-3 PUFA (0.8 g kg(-1) day(-1) for 2 months). Ovariectomy caused endothelial dysfunction to acetylcholine, which was reversed by superoxide scavenger Tiron. Erythrocyte membrane lipid composition was characterized by reduced n-3 PUFA total content and omega-3 index, and by concomitant increase in n-6:n-3 PUFA ratio. Ovariectomy-related oxidative stress, demonstrated by both enhanced superoxide production and 3-nitrotyrosine expression in aorta, was associated with increased nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit NOX-4 protein expression. Endothelial nitric oxide synthase (eNOS) functional inhibition by l-NG-nitroarginine methyl ester, protein expression and activity did not change. In ovariectomized rats, treatment with n-3 PUFA increased n-3 PUFA total content and omega-3 index and decreased n-6:n-3 PUFA ratio in erythrocyte membrane, reversed vascular oxidative stress, endothelial dysfunction, aortic 3-nitrotyrosine and markedly lowered NOX-4 protein expression; eNOS protein expression also increased, paralleled by reversal of inhibitory binding to Caveolin-1, while ex-vivo functional inhibition and NOS synthesis were unchanged. These findings demonstrate in vivo a therapeutic benefit of n-3 PUFA on menopause-associated endothelial dysfunction by reversal of alterations in membrane lipid composition induced by ovariectomy and by reduction of vascular oxidative stress. In this setting they also identify NOX-4 as a potential target to reduce oxidative stress-mediated vascular complications.

Treating hyperglycemia improves skeletal muscle protein metabolism in cancer patients after major surgery.

OBJECTIVE: Cancer and surgical stress interact to aggravate insulin resistance, protein catabolism, and glutamine depletion in skeletal muscle. We compared the effects of insulin-mediated euglycemia and moderate hyperglycemia on kinetics of protein and selected amino acids in skeletal muscle of female cancer patients after major surgery. DESIGN: In each patient, a 24-hr period of insulin-mediated tight euglycemia (mean blood glucose, 5.8 +/- 0.4 mmol/L) preceded or followed a 24-hr control period of moderate hyperglycemia (mean blood glucose, 9.6 +/- 0.6 mmol/L) on the first and second day after surgery, in randomized order, according to a crossover experimental design. SETTING: Intensive care unit, cancer hospital. PATIENTS: Cancer patients after abdominal radical surgery combined with intraoperative radiation therapy. INTERVENTIONS: Intensive (57 +/- 11 units/24 hrs) and conventional (25 +/- 5 units/24 hrs) insulin treatment during total parenteral nutrition. MEASUREMENTS AND MAIN RESULTS: Muscle metabolism was assessed at the end of each 24-hr period of euglycemia and of hyperglycemia by leg arteriovenous catheterization with stable isotopic tracers. We found that euglycemia as compared with hyperglycemia was associated with higher (p < .05) fractional glucose uptake (16% +/- 4% vs. 9% +/- 3%); higher (p < .05) muscle protein synthesis and neutral net protein balance (-3 +/- 3 vs. -11 +/- 3 nmol phenylalanine x 100 mL(-1) x min(-1), respectively); lower (-52% +/- 12%, p < .01) muscle nonprotein leucine disposal (an index of leucine oxidation) and higher (p < .05) plasma leucine concentrations; and higher (3.6 +/- 1.7 times, p < .01) net de novo muscle glutamine synthesis and plasma glutamine concentrations (p < .05). Euglycemia was associated with higher (23% +/- 7%, p < .05) plasma concentrations of arginine but did not affect either arginine release from muscle or plasma concentration and muscle flux of asymmetrical dimethylarginine. Rate of muscle proteolysis correlated (p < .05) with muscle release of asymmetrical dimethylarginine. CONCLUSIONS: Treating hyperglycemia improves skeletal muscle protein and amino acid metabolism in cancer patients after major surgery.

Insulin action on glucose and protein metabolism during L-carnitine supplementation in maintenance haemodialysis patients.

BACKGROUND: Impaired protein anabolism and insulin resistance are characteristic features of maintenance haemodialysis patients. We have used a randomised, matched-paired, double-blind, placebo-controlled experimental design to determine the capability of intravenous L-carnitine supplementation to modify insulin resistance and protein catabolism in non-diabetic patients with end-stage renal disease (ESRD) undergoing chronic haemodialysis treatment. METHODS: L-carnitine (20 mg x kg(-1)) (n = 9) or placebo (n = 10) were given intravenously at the end of seven consecutive dialysis sessions. Whole-body protein and glucose metabolism were assessed on interdialytic days by the L[1-(13)C]leucine and the [2,2-(2)H(2)]glucose kinetic models in the postabsorptive state and during euglicemic hyperinsulinemic clamp studies at baseline and at the end of the treatment period. RESULTS: L-carnitine supplementation was associated with lower (P < 0.05) rates of leucine oxidation (-11 +/- 12%) and appearance from proteolysis (-6 +/- 2%) during the clamp studies than after placebo supplementation. The rates of glucose appearance in the postabsorptive state did not change significantly in the patients receiving L-carnitine treatment. Insulin-mediated glucose disappearance was improved by L-carnitine only in those patients (n = 5) (+18 +/- 3%, P < 0.05 vs placebo group, n = 5) with greater baseline insulin resistance, selected according to the median value of insulin sensitivity before treatment. CONCLUSIONS: L-carnitine supplementation was associated with protein-sparing effects in maintenance haemodialysis patients during hyperinsulinemia.