Inflammation and l-carnitine therapy in hemodialysis patients: a review

Neuroprotective effects of L-carnitine towards oxidative stress and inflammatory processes: a review of its importance as a therapeutic drug in some disorders

L-carnitine (LC) is a natural compound crucial for transporting long-chain fatty acids into mitochondria for ATP production. It is found mainly in red meat, fish, and dairy products, in addition to being synthesized by the body. LC is supplemented in patients with organic acidemias since it corrects secondary carnitine deficiency and accelerates the removal of the accumulated acyl organic acid derivative groups. Recently, it was also shown to behave as an antioxidant and an anti-inflammatory agent in various pathological conditions like hypertension, diabetes, and neurodegenerative diseases. Inflammation is a complex response to tissue damage or infection associated with oxidative stress. LC has been implicated in reducing inflammatory cytokines and other biomarkers. Recent studies suggest that LC supplementation reduces inflammation in chronic kidney disease, cardiovascular disease, and neuroinflammation. LC supplementation has been effective in reducing inflammatory markers like C-reactive protein (CRP) and interleukins (IL-6, TNF-α) in various pathologies, including septic shock and polycystic ovary syndrome (PCOS). It has also been shown to reduce cardiovascular events in patients with end-stage renal disease. In experimental models, LC revealed neuroprotective effects, improving memory and reducing neuronal death. Additionally, in spinal cord ischemia-reperfusion injury and acute myocardial infarction, LC treatment diminished inflammation and oxidative stress while improving neurological and cardiac functions. In conclusion, LC supplementation demonstrates significant potential properties in reducing inflammation and improving health outcomes in various pathological conditions, making it a subject of increasing interest in medical research. This article aims to review the literature on the anti-inflammatory and antioxidant effects of LC in different pathologies.

Fucoidan alleviated colitis aggravated by fiber deficiency through protecting the gut barrier, suppressing the MAPK/NF-κB pathway, and modulating gut microbiota and metabolites

Insufficient dietary fiber intake has become a global public health issue, affecting the development and management of various diseases, including intestinal diseases and obesity. This study showed that dietary fiber deficiency enhanced the susceptibility of mice to colitis, which could be attributed to the disruption of the gut barrier integrity, activation of the NF-κB pathway, and oxidative stress. Undaria pinnatifida fucoidan (UPF) alleviated colitis symptoms in mice that fed with a fiber deficient diet (FD), characterized by increased weight gain and reduced disease activity index, liver and spleen indexes, and histological score. The protective effect of UPF against FD-exacerbated colitis can be attributed to the alleviation of oxidative stress, the preservation of the gut barrier integrity, and inhibition of the MAPK/NF-κB pathway. UPF ameliorated the gut microbiota composition, leading to increased microbiota richness, as well as increased levels of Muribaculaceae, Lactobacillaceae, and Bifidobacterium and reduced levels of Proteobacteria, Bacteroidetes, and Bacteroides. Metabolomics analysis revealed that UPF improved the profile of microbiota metabolites, with increased levels of carnitine and taurine and decreased levels of tyrosine and deoxycholic acid. This study suggests that UPF has the potential to be developed as a novel prebiotic agent to enhance human health.

The effects of L-carnitine supplementation on cardiovascular risk factors in participants with impaired glucose tolerance and diabetes: a systematic review and dose-response meta-analysis

AIMS

L-carnitine plays a role related to cardiometabolic factors, but its effectiveness and safety in CVD are still unknown. We aim to assess the effect of L-carnitine supplementation on CVD risk factors.

METHODS

A systematic literature search was conducted in PubMed, Web of Science, and Scopus until October 2022. The main outcomes were lipid profiles, anthropometric parameters, insulin resistance, serum glucose levels, leptin, blood pressure, and inflammatory markers. The pooled weighted mean difference (WMD) was calculated using a random-effects model.

RESULTS

We included the 21 RCTs (n = 2900) with 21 effect sizes in this study. L-carnitine supplementation had a significant effect on TG (WMD = - 13.50 mg/dl, p = 0.039), LDL (WMD = - 12.66 mg/dl, p < 0.001), FBG (WMD = - 6.24 mg/dl, p = 0.001), HbA1c (WMD = -0.37%, p = 0.013) HOMA-IR (WMD = -0.72, p = 0.038 (, CRP (WMD = - 0.07 mg/dl, P = 0.037), TNF-α (WMD = - 1.39 pg/ml, p = 0.033), weight (WMD = - 1.58 kg, p = 0.001 (, BMI (WMD = - 0.28 kg/m2, p = 0.017(, BFP (WMD = - 1.83, p < 0.001) and leptin (WMD = - 2.21 ng/ml, p = 0.003 (in intervention, compared to the placebo group, in the pooled analysis.

CONCLUSIONS

This meta-analysis demonstrated that administration of L-carnitine in diabetic and glucose intolerance patients can significantly reduce TG, LDL-C, FBG, HbA1c, HOMA-IR, CRP, TNF-α, weight, BMI, BFP, and leptin levels. PROSPERO registration code: CRD42022366992.

Hyperlipoproteinemia (a) and Phytoestrogen Therapy in Dialysis Patients: A Review

PURPOSE

Hyperlipoproteinemia (a) is a prevalent complication in dialysis patients, with no valid treatment strategy. The aim of this narrative review was to investigate the clinical significance of hyperlipoproteinemia (a) and phytoestrogen therapy in dialysis patients.

METHODS

A comprehensive literature search of the published data was performed regarding the effects of phytoestrogen therapy on hyperlipoproteinemia (a) in dialysis patients.

FINDINGS

Hyperlipoproteinemia (a) occurs in dialysis patients due to decreased catabolism and increased synthesis of lipoprotein (a) [Lp(a)]. A few clinical trials have studied the effects of phytoestrogens on serum Lp(a). All studies of dialysis patients or nonuremic individuals with hyperlipoproteinemia (a), except one, showed that phytoestrogens could significantly reduce serum Lp(a) levels. However, all investigations of phytoestrogen therapy in individuals with normal serum Lp(a) levels showed that it had no effect on serum Lp(a). Phytoestrogens seem to have effects similar to those of estrogen in lowering Lp(a) concentrations.

IMPLICATIONS

Considering the high prevalence of hyperlipoproteinemia (a) in dialysis patients, phytoestrogen therapy is a reasonable approach for reducing serum Lp(a) levels and its complications in these patients.

The effect of l-carnitine supplementation on mortality and clinical outcomes in ventilator-dependent critically ill patients with obesity and COVID-19: Protocol for a randomized double-blind placebo-controlled trial

BACKGROUND

Coronavirus disease 2019 (COVID-19) still remains a pandemic accounting for at least 15% of intensive care unit (ICU) admissions. Recently, it has been observed that l-carnitine levels, which play an important role in fatty acid metabolism, have an inverse association with the severity of COVID-19 and its complications, hence a potential role for supplementing with this nutraceutical has been suggested. The current protocol describes a trial aiming to an evaluation of the effect of l-carnitine intervention on mortality and clinical outcomes in ICU-admitted patients with COVID-19.

METHODS

This parallel-group, randomized, placebo-controlled, and double-blind clinical trial involves 50 participants and will be performed at the ICU of Artesh (AJA) Hospital, Mashhad, IRAN. Eligible participants will be randomized into two groups: 1) the intervention group will receive 1000 mg l-carnitine capsules 3 times a day, and 2) the placebo group will receive 1000 mg placebo capsules 3 times a day. Assessments will be performed at baseline, 7 and 28 days after study initiation. The primary outcome includes changes in serum levels of C-reactive protein (CRP). Secondary outcomes include the length of stay in the ICU, ICU mortality, hospital mortality, 28-day mortality, duration of mechanical ventilation (MV), and the neutrophil-lymphocyte ratio (NLR).

CONCLUSION

Based on previous evidence, l-carnitine may reduce inflammation and oxidation stress and improve respiratory function. However, the effects of l-carnitine on ventilator-dependent COVID-19 critically ill patients have not been assessed yet, justifying the necessity to conduct a clinical study in this field. c.

Ascophyllum nodosum polysaccharide regulates gut microbiota metabolites to protect against colonic inflammation in mice

Ascophyllum nodosum polysaccharide (ANP) can protect against colonic inflammation but the underlying mechanism is still unclear. This study has determined the metabolites of gut microbiota regulated by ANP to reveal the mechanism of the anti-inflammation effect of ANP. Using an in vitro colonic fermentation model, the results indicate that gut microbiota could utilize a proportion of ANP to increase the concentrations of short-chain fatty acids (SCFAs) and decrease ammonia content. Metabolomics revealed that 46 differential metabolites, such as betaine, L-carnitine, and aminoimidazole carboxamide ribonucleotide (AICAR), could be altered by ANP. Metabolic pathway analysis showed that ANP mainly up-regulated the phenylalanine, tyrosine, and tryptophan biosynthesis and aminoacyl-tRNA biosynthesis, which were negatively correlated with inflammation progression. Interestingly, these metabolites associated with inflammation were also up-regulated by ANP in colitis mice, including betaine, L-carnitine, AICAR, N-acetyl-glutamine, tryptophan, and valine, which were mainly associated with amino acid metabolism and aminoacyl-tRNA biosynthesis. Furthermore, the metabolites modulated by ANP were associated with the relative abundances of Akkermansia, Bacteroides, Blautia, Coprobacillus, Enterobacter, and Klebsiella. Additionally, based on VIP values, betaine is a key metabolite after the ANP supplement in vitro and in vivo. As indicated by these findings, ANP can up-regulate the production of SCFAs, betaine, L-carnitine, and AICAR and aminoacyl-tRNA biosynthesis to protect against colonic inflammation and maintain intestinal health.

Prognostic value of the combination of neutrophil-to-lymphocyte ratio, monocyte-to-lymphocyte ratio and platelet-to-lymphocyte ratio on mortality in patients on maintenance hemodialysis

BACKGROUND

Hemodialysis (HD) is the most important renal replacement therapy for patients with end-stage kidney disease (ESKD). Systemic inflammation is a risk factor of mortality in HD patients. Neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) are new inflammatory markers. However, previous studies have inconsistent conclusions about the predictive value of NLR, MLR and PLR on mortality of HD patients. The aim of this study was to establish an inflammation scoring system by including NLR, MLR and PLR, and evaluate the association between the inflammation score and all-cause and cardiovascular mortality in HD patients.

METHODS

In this single center retrospective cohort study, 213 incident HD patients from January 1, 2015 to December 31, 2020 were included. Baseline demographic and clinical data and laboratory measurements were collected. According to the optimal cut-off values, NLR, MLR and PLR were assigned 0 or 1 point, respectively. Then, the inflammation score was obtained by adding the NLR, MLR and PLR scores. All patients were followed until July 31, 2021. The associations of the inflammation score with all-cause and cardiovascular mortality were assessed by multivariable-adjusted Cox models.

RESULTS

Of 213 patients, the mean (± SD) age was 56.8 ± 14.4 years, 66.2% were men, and 32.9% with diabetes. The primary cause of ESKD was mainly chronic glomerulonephritis (46.5%) and diabetic nephropathy (28.6%). The median inflammation score was 2 (interquartile range = 1-3). During a median 30 months (interquartile range = 17-50 months) follow-up period, 53 patients had died, of which 33 deaths were caused by cardiovascular disease. After adjusting for demographics, primary diseases and other confounders in multivariable model, the inflammation score = 3 was associated with a hazard ratio for all-cause mortality of 4.562 (95% confidence interval, 1.342-15.504, P = 0.015) and a hazard ratio for cardiovascular mortality of 4.027 (95% confidence interval, 0.882-18.384, P = 0.072).

CONCLUSION

In conclusion, an inflammation scoring system was established by including NLR, MLR and PLR, and the higher inflammation score was independently associated with all-cause mortality in HD patients.

The upregulation of Nur77 decreases ketamine-induced hippocampal neurons toxicity in rats

Ketamine is clinically used as a narcotic. However, ketamine has certain deficits and produces toxicity to neurons. As a member of the NR4A receptor subfamily, Nur77 decreases neurodegenerative disorders. The study aims to investigate the effects of upregulated Nur77 on ketamine-induced rat hippocampal neurons damage and the active mechanism. Neurons were obtained from rat hippocampal and identified by immunofluorescence assays. The treatment groups contained ketamine group, Nur77 group, ketamine + Nur77 group and ketamine + L-cam group. Neurons apoptosis and reactive oxygen species (ROS) were determined by a related kit using flow cytometry. Enzyme NAD(P)H quinone oxidoreductase 1 (NQO1), enzyme heme oxygenase 1 (HO1), Nur77, the expression of Bax, Bcl-2 and cleaved-caspase-3 and inflammatory cytokines were measured using western blot assays and reverse transcription-quantitative PCR (RT-qPCR) assays. Ketamine-induced neurons apoptosis; however, Nur77 decreased ketamine-induced neurons apoptosis. A low level of ROS was observed in two combination groups. Neurons treated by ketamine only had the lowest levels of Nur77, NQO1 and HO1, compared with other treatment groups. The levels of Bax and cleaved-caspase-3 in two combination groups were lower than those in the ketamine group. Furthermore, the ketamine group had higher levels of tumor necrosis factor alpha, IL-1β and IL-6 but the lowest level of IL-4. Upregulated Nur77 reduced the ketamine-induced toxicity in neurons. The mechanism of Nur77 involved antioxidation, apoptosis signaling pathway and inflammation signaling pathway. Our study provides a novel therapy that could attenuate ketamine-induced toxicity.

The Effects of L-Carnitine, Acetyl-L-Carnitine, and Propionyl-L-Carnitine on Body Mass in Type 2 Diabetes Mellitus Patients

Purpose: The study aimed to explore the effects of l-carnitine, acetyl-l-carnitine, and propionyl-l-carnitine on Body Mass in type 2 diabetes mellitus (T2DM) patients.

Methods: Randomized controlled trial (RCT) studies of l-carnitine, acetyl-l-carnitine, and propionyl-l-carnitine in T2DM patients were searched. The change rates of Body Mass index (BMI) from baseline values were used as an evaluation indicator. The maximal effect (E_max) model by non-linear mixed-effect modeling (NONMEM) was used as the evaluation method.

Results: A total of 10 RCT studies, 1239 T2DM patients were included for analysis, including eight studies of l-carnitine, one study of acetyl-l-carnitine, and one study of propionyl-l-carnitine. The study found that l-carnitine could reduce the Body Mass of T2DM patients. Based on only one study each for acetyl-l-carnitine and propionyl-l-carnitine, no significant effects were found in acetyl-l-carnitine or propionyl-l-carnitine. In addition, in order to achieve a plateau of efficacy (80% E_max), 2 g/day l-carnitine was required for at least 2 weeks.

Conclusions: Two g/day l-carnitine was required for at least 2 weeks to affect Body Mass in T2DM patients, and no significant effects were found in acetyl-l-carnitine or propionyl-l-carnitine.

Dietary supplementary glutamine and L-carnitine enhanced the anti-cold stress of Arbor Acres broilers

Newborn poultry in cold regions often suffer from cold stress, causing a series of changes in their physiology and metabolism, leading to slow growth and decreased production performance. However, a single anti-stress substance cannot completely or maximally eliminate or alleviate the various effects of cold stress on animals. Therefore, the effects of the supplemented glutamine and L-carnitine on broilers under low temperature were evaluated in this study. Broilers were randomly allocated into 16 groups which were respectively fed with different levels of glutamine and L-carnitine according to the L16 (45) orthogonal experimental design for 3 weeks (the first week is the adaptive feeding period; the second and third weeks are the cold exposure period). Growth performance was recorded, and blood samples were collected during cold exposure. The results showed the supplementation had altered the plasma parameters, growth performance and cold-induced oxidative stress. The increase of corticosterone and suppression of thyroid hormone was ameliorated. Supplemented groups had lower daily feed intake and feed-to-gain ratio, higher daily weight gain and better relative weights of immune organs. Plasma glucose, total protein, blood urea nitrogen and alkaline phosphatase changed as well. Oxidative stress was mollified due to the improved activities of superoxide dismutase and glutathione peroxidase, heightened total antioxidant capacity and stable malondialdehyde. Dietary glutamine and L-carnitine improve the growth performance, nutritional status and cold stress response of broilers at low temperature, and their interaction occurred.

Quantitative efficacy of L-carnitine supplementation on glycemic control in type 2 diabetes mellitus patients

OBJECTIVES

This study aimed to explore the quantitative efficacy of L-carnitine supplementation on glycemic control in type 2 diabetes mellitus patients using model-based meta-analysis (MBMA).

METHODS

Literatures were retrieved from the public database and data from these trials were extracted. The quantitative efficacy of L-carnitine on fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c) in type 2 diabetes mellitus patients were evaluated by maximal effect (E_max) models with nonlinear mixed effects modeling (NONMEM).

RESULTS

In the model of FPG, E_max and _treatment duration to reach half of the maximal effects (ET₅₀) were -9.8% and 36.1 weeks, respectively. In the model of HbA1c, E_max and ET₅₀ were -19.6% and 106 weeks, respectively. In addition, the durations for achieving 25%, 50%, 75%, 80%, and 90% E_max of L-carnitine on FPG were 13, 36.1, 118, 160, and 390 weeks, respectively. The durations for achieving 25%, 50%, 75%, 80%, and 90% E_max of L-carnitine on HbA1c were 38, 106, 334, 449, and 1058 weeks, respectively.

CONCLUSIONS

It was the first time to provide valuable quantitative information for efficacy of L-carnitine supplementation on glycemic control in type 2 diabetes mellitus patients.

L-Carnitine Tartrate Downregulates the ACE2 Receptor and Limits SARS-CoV-2 Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been responsible for one of the worst pandemics in modern history. Several prevention and treatment strategies have been designed and evaluated in recent months either through the repurposing of existing treatments or the development of new drugs and vaccines. In this study, we show that L-carnitine tartrate supplementation in humans and rodents led to significant decreases of key host dependency factors, notably angiotensin-converting enzyme 2 (ACE2), transmembrane protease serine 2 (TMPRSS2), and Furin, which are responsible for viral attachment, viral spike S-protein cleavage, and priming for viral fusion and entry. Interestingly, pre-treatment of Calu-3, human lung epithelial cells, with L-carnitine tartrate led to a significant and dose-dependent inhibition of the infection by SARS-CoV-2. Infection inhibition coincided with a significant decrease in ACE2 mRNA expression levels. These data suggest that L-carnitine tartrate should be tested with appropriate trials in humans for the possibility to limit SARS-CoV-2 infection.

The efficacy of L-carnitine in improving malnutrition in patients on maintenance hemodialysis: a meta-analysis

The improvement of malnutrition with levocarnitine in maintenance hemodialysis (MHD) patients is controversial. We performed a meta-analysis to evaluate the efficacy of levocarnitine in improving malnutrition in MHD patients. We performed a literature search for relevant articles related to the treatment of malnutrition by L-carnitine in MHD patients in PubMed, Embase, Web of Science, China National Knowledge Infrastructure, and Wanfang databases. We set the publication dates from 1950 to July 2019. The levels of albumin, prealbumin, total protein, and transferrin before and after treatment were used for assessing malnutrition. Twenty-seven studies were included in the present analysis. The results of the random effects model indicated that L-carnitine treatment improved the albumin level in patients on MHD patients. The pooled standardized mean difference of albumin level was 2.51 (95% confidence interval (CI): 2.13-2.90, P<0.001). The pooled total protein level was 3.83 (95% CI: 2.41-5.24, P = 0.000) and the pooled transferrin level was 0.35 (95% CI: 0.18-0.52, P = 0.000). Significant differences were observed with the total protein and transferrin levels. The results indicated that levocarnitine significantly improved the prealbumin level in patients on MHD. The pooled prealbumin level was 70.86 (95% CI: 42.99-98.73, P = 0.000). No publication bias was detected (P>0.05). The present meta-analysis indicated that L-carnitine can have a favorable effect on malnutrition biomarkers in patients on MHD, including the increase in albumin, total protein, transferrin, and prealbumin levels. The L-carnitine could be an option for treatment of MHD patients.

The effects of nanocurcumin supplementation on inflammation in hemodialysis patients: A randomized controlled trial

INTRODUCTION

Serum levels of several pro-inflammatory cytokines are higher in hemodialysis patients compared to healthy people. Curcumin has been shown to be able to decrease cytokines levels in nonuremic subjects. Our goal was to evaluate the effect of nanocurcumin administration on cytokines levels in hemodialysis patients.

METHODS

The study was performed over a 3 months period on 54 hemodialysis patients who had been randomized to receive either nanocurcumin or placebo. Serum levels and gene expressions of tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6) were evaluated using enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (RT-PCR).

FINDINGS

Serum levels of IL-6 and TNF-α were similar in the two groups at baseline but were lower after 12 weeks of treatment with nanocurcumin compared to placebo (P = 0.024 for IL-6 and 0.02 for TNF). In the group given nanocurcumin, serum levels of both cytokines decreased substantially (P < 0.001 for each), whereas they were unchanged in the group given placebo. Gene expression for each cytokine in peripheral blood mononuclear cells (PBMCs) was reduced at 12 weeks vs. baseline in the group given nanocurcumin, and changes in gene expression correlated with changes in serum level for each of the two cytokines.

DISCUSSION

The results indicate that nanocurcumin supplementation reduces both serum levels and gene expression of IL-6 and TNF-α in hemodialysis patients. The feasibility and potential clinical benefits of nanocurcumin treatment to reduce inflammation in hemodialysis patients warrant further study.

Exploration of anti-inflammatory mechanism of forsythiaside A and forsythiaside B in CuSO4-induced inflammation in zebrafish by metabolomic and proteomic analyses

BACKGROUND

Inflammation is a general pathological phenomenon during severe disturbances to the homeostasis. Forsythiaside A (FA) and forsythiaside B (FB), isolated from the dried fruit of Forsythia suspensa (Thunb.) Vahl, are phenylethanoid compounds that show a significant anti-inflammatory effect. However, the properties and therapeutic mechanisms of this effect have not yet been systematically elucidated.

METHODS

In this study, the anti-inflammatory effects of FA and FB were investigated in CuSO₄-induced inflammation in zebrafish larvae. Intracellular generation of reactive oxygen species (ROS) and nitric oxide (NO) was investigated using fluorescence probes. Metabolomic and proteomic analyses using liquid chromatography-mass spectrometry were carried out to identify the expressions of metabolites and proteins associated with the anti-inflammatory mechanism of FA and FB. Quantitative polymerase chain reaction (PCR) was performed to detect the progressive changes in gene expression.

RESULTS

FA and FB inhibited neutrophils migration to the damaged neuromasts and remarkably reduced CuSO₄-induced ROS and NO generation in zebrafish larvae. Metabolomic analysis pointed to the involvement of nicotinate and nicotinamide metabolism, energy metabolism, pyrimidine metabolism, and purine metabolism. Proteomic analysis identified 146 differentially expressed proteins between the control and model groups. These included collagen [collagen type II alpha 1b precursor (col2a1b), collagen alpha-2(IX) chain precursor (col9a2), collagen type IX alpha I precursor (col9a1b)], nucleoside diphosphate kinase 3 isoform X1 (Nme3), WD repeat-containing protein 3 (Wdr3), and 28S ribosomal protein S7 mitochondrial precursor (Mrps7). FA and FB were shown to reverse the abnormal expressions of potential metabolite and protein biomarkers and alleviate CuSO₄-induced damage to the neuromasts in the zebrafish lateral line.

CONCLUSIONS

Our results indicate that FA and FB possess remarkable anti-inflammatory properties, protecting against CuSO₄-induced neuromasts damage in zebrafish larvae. The results also suggest a multi-component and multi-regulatory therapeutic mechanism for FA and FB.

Effects of soy isoflavones on serum systemic and vascular inflammation markers and oxidative stress in peritoneal dialysis patients: A randomized controlled trial

Cardiovascular disease (CVD) is common in peritoneal dialysis (PD) patients. This study was designed to investigate the effects of isoflavones on systemic and vascular inflammation markers and oxidative stress in PD patients. In this randomized clinical trial, 40 PD patients were randomly assigned to either the isoflavone or the placebo group. The isoflavone group received 100 mg soy isoflavones daily for 8 weeks, whereas the placebo group received corresponding placebos. At baseline and the end of eighth week, serum high sensitive C-reactive protein (hs-CRP), intercellular adhesion molecule type 1 (ICAM-1), vascular cell adhesion molecule type 1 (VCAM-1), E-selectin, and malondialdehyde were measured. Serum VCAM-1 decreased significantly in the isoflavone group at the end of Week 8 compared to baseline (p = .01), whereas no significant change was observed in the placebo group. Serum ICAM-1 decreased significantly in the isoflavone (p = .01) and placebo (p = .01) group compared to baseline. However, the reduction of ICAM-1 was significantly higher in the isoflavone group than in the placebo group (p = .02). There were no significant differences between the two groups in mean changes of serum E-selectin, malondialdehyde, and hs-CRP. This study indicates that isoflavones reduce serum VCAM-1 and ICAM-1, which are two CVD risk factors, in PD patients.

Exosomes in inflammation and role as biomarkers

Exosomes are endosomal-derived nano-vesicles. They are considered vehicles through which donor cells transfer proteins, lipids and nucleic acids to target cells thus influencing their metabolism. Exosomes are involved in inflammatory processes that play a pivotal role in a large number of pathologic states including cancer, inflammatory bowel diseases, type 2 diabetes, obesity, rheumatoid arthritis and neurodegenerative diseases. The association between inflammation and change in nature or expression level of some exosomal cargos is the fundamental step for identifying possible novel biomarkers of inflammatory-based diseases. A novel interesting exosome cargo is the SLC22A5 transport protein whose level in exosomes is regulated by the pro-inflammatory cytokine INF-γ. The advantage of using exosomes as a biomarker vehicle consists of their ease of collection from body fluids such as urine and saliva as they may represent a non-invasive means for screening human pathology.

Characterization of Exosomal SLC22A5 (OCTN2) carnitine transporter

Exosomes are extracellular vesicles involved in cell-to-cell communication. Previous large scale proteomics revealed that they contain SLC proteins. However, no data on the function of exosomal SLCs is available, so far. An SLC localized in exosomes was here characterized for the first time: the carnitine transporter OCTN2 (SLC22A5). The protein was detected by Western Blot analysis in HEK293 exosomes. To investigate the functional properties of the exosomal OCTN2, the proteins extracted from vesicles were reconstituted into proteolipsomes and the transport function was measured as uptake of ³H-carnitine. Transport was stimulated by sodium and was dependent on pH. ³H-carnitine uptake was inhibited by Acetyl-carnitine, but not by Asn, Gln and Arg thus excluding interference by ATB^0,+, an amino acid transporter which also recognizes carnitine. Cardiolipin failed to stimulate transport, excluding the activity of the mitochondrial Carnitine/acylcarnitine transporter. Increased level of exosomal OCTN2 was induced by treatment of HEK293 with the pro-inflammatory cytokine INFγ. All data concurred to demonstrate that OCTN2 present in exosomes is fully functional and is in its native conformation. Functional OCTN2 was detected also in human urinary exosomes, thus suggesting the OCTN2 exosomal protein as a candidate biomarker for inflammation related pathologies.

Effects of a Novel Nutritional Formula Enriched With Eicosapentaenoic Acid and Docosahexaenoic Acid Specially Developed for Tube-Fed Hemodialysis Patients

OBJECTIVE

To evaluate the effects of a nutritional formula enriched with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in tube-fed bedridden hemodialysis patients.

DESIGN

A prospective, multicenter, single-arm study.

SETTING

Koyukai Memorial Hospital, Orimoto Hospital, and Chofu Hospital, Japan.

SUBJECTS

Eleven tube-fed bedridden hemodialysis patients.

INTERVENTION

Patients were fed a nutritional formula enriched with EPA and DHA for 12 weeks.

MAIN OUTCOME MEASURES

Body weight; body mass index (BMI); serum levels of total protein, albumin, prealbumin, total cholesterol, triglyceride, and C-reactive protein (CRP); serum fatty acid composition.

RESULTS

Body weight; BMI; and serum levels of total protein, albumin, total cholesterol, triglyceride, and CRP at 12 weeks were not significantly different from baseline levels. Serum prealbumin, EPA, and DHA levels significantly increased after 12 weeks of treatment.

CONCLUSIONS

A nutritional formula enriched with EPA and DHA may be beneficial for nutritional management in tube-fed bedridden hemodialysis patients.

L-Carnitine improves gastrointestinal disorders and altered the intestinal microbiota in hemodialysis patients

Patients receiving hemodialysis also manifest gastrointestinal symptoms, such as constipation, caused by restriction of water intake and the loss of body water balance. Because dietary carnitine deficiency is considered to cause smooth muscle dysmotility of the gastrointestinal tract similarly to that in skeletal muscles, carnitine deficiency in hemodialysis patients may be one cause of gastrointestinal discomfort and dysfunctions. We performed a multicenter nonrandomized single-arm prospective clinical trial. Fifteen Japanese patients receiving hemodialysis were administered L-carnitine tablets (900 mg) for 3 months, and clinical and biochemical analyses were performed before and after treatment. The serum total carnitine level was increased significantly by supplementation with L-carnitine for 3 months (from 40.9 ± 2.6 μmol/l to 172.3 ± 19.0 μmol/l, p<0.05). The myasthenia score was decreased significantly by the supplementation (from 1.3 ± 0.3 to 0.8 ± 0.2, p<0.05). The frequency of passing stool tended to increase with the treatment for 3 months (from 4.2 ± 0.5 times/week to 4.8 ± 0.5 times/week). A phyla-level analysis of the microbiota showed that the composition of the individual microbiota was not different between before and after supplementation. A genus-level analysis, however, revealed that the relative abundance of genus Clostridium subcluster 4 was significantly decreased by the supplementation (from 7.7 ± 1.9% to 4.7 ± 1.3%, p<0.05). Oral supplementation of L-carnitine to the patients receiving hemodialysis improved not only their muscle discomfort but also their gastrointestinal disorders and microbiota, although its effect on the prognosis of hemodialysis patients should be further investigated.