L-Carnitine in the treatment of fatigue in adult celiac disease patients: a pilot study

Celiac Disease: An Academy of Nutrition and Dietetics Evidence-Based Nutrition Practice Guideline

Celiac disease is an autoimmune disorder in which the immune system of genetically susceptible individuals elicits a reaction to gluten causing small intestine damage. If left undiagnosed and untreated, the resulting nutrition malabsorption can lead to anemia, bone disease, growth faltering, or other consequences. The condition is lifelong and lacks a cure; the only treatment is lifelong adherence to a gluten-free diet (GFD). This diet is challenging to follow and adversely influences quality of life; however, it is essential to ensure intestinal recovery and prevent future negative health consequences. The Academy of Nutrition and Dietetics convened an expert panel complemented by a celiac disease patient advocate to evaluate evidence for six topics, including medical nutrition therapy; the GFD; oat consumption; micronutrients; pro-/prebiotics; and the low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols diet. This publication outlines the Academy of Nutrition and Dietetics Evidence Analysis Library methods used to complete the systematic review and guideline development, and summarizes the recommendations and supporting evidence. The guidelines affirm that all individuals with celiac disease should follow a GFD (1C, Imperative) that may include gluten-free oats in adults (2D, Conditional). Children should follow a nutritionally adequate GFD that supports healthy growth and development (Consensus, Imperative) and does not unnecessarily restrict gluten-free oats (Consensus, Conditional). The guidelines indicate nutritional care should include routine nutritional assessment (Consensus, Imperative) and medical nutrition therapy (Consensus, Imperative). At this time, the guidelines do not support a recommendation for the addition of the low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols diet (2C, Conditional); prebiotic or probiotic supplementation (2D, Conditional); or micronutrient supplementation (in the absence of nutritional deficiency) (Consensus, Conditional). The 2021 Celiac Disease Evidence-Based Nutrition Guideline will assist registered dietitian nutritionists in providing appropriate evidence-based medical nutrition therapy to support people with celiac disease in achieving and maintaining nutritional health and avoiding adverse celiac disease consequences throughout their lives.

Carnitine metabolites and cognitive improvement in patients with schizophrenia treated with olanzapine: a prospective longitudinal study

Objective: Cognitive impairment is one of the core symptoms of schizophrenia, which is stable and lifelong. L-carnitine has been shown to improve cognitive function and decrease the rate of cognitive deterioration in patients with Alzheimer's disease. However, it remains unclear regarding the role of L-carnitine and its metabolites in cognitive functions in schizophrenia after treatment with olanzapine. The purpose of this study was to evaluate the relationship between changes in plasma levels of L-carnitine metabolites and cognitive improvement after olanzapine treatment. Methods: This was a prospective longitudinal study. In this study, we recruited 25 female patients with first episode schizophrenia (FES) who were drug naïve at baseline and received 4 weeks of olanzapine monotherapy. Cognitive function was assessed at baseline and 4-week follow-up using the RBANS. Plasma L-carnitine metabolite levels were determined by a metabolomics technology based on untargeted ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Results: We found that the immediate memory index, delayed memory index and RBANS composite score were significantly increased at the 4-week follow-up after treatment. A total of 7 differential L-carnitine metabolites were identified in FES patients after olanzapine monotherapy. In addition, we found that changes in butyrylcarnitine were positively correlated with improvements in language index and RBANS composite score. Further regression analyses confirmed the association between reduced butyrylcarnitine levels and cognitive improvement after olanzapine monotherapy in FES patients. Conclusion: Our study shows that cognitive improvement after olanzapine treatment was associated with changes in L-carnitine metabolite levels in patients with FES, suggesting a key role of L-carnitine in cognition in schizophrenia.

Acetyl-L-carnitine in chronic pain: A narrative review

Acetyl-L-carnitine (ALC) is an endogenous molecule that not only plays a role in energy metabolism, but also has antioxidant properties, protects from oxidative stress, modulates brain neurotransmitters such as acetylcholine, serotonin and dopamine, and acts on neurotrophic factors such as nerve growth factor (NGF) and metabotropic glutamate (mGlu) receptors by means of epigenetic mechanisms. Importantly, it induces mGlu2 expression at nerve terminals, thus giving rise to analgesia and preventing spinal sensitisation. It has also been found to have even long-term neurotrophic and analgesic activity in experimental models of chronic inflammatory and neuropathic pain. The aim of this narrative review is to summarise the current evidence regarding the use of ALC in patients with chronic pain, and cognitive and mood disorders, and investigate the rationale underlying its use in patients with fibromyalgia syndrome, which is characterised by nociplastic changes that increase the sensitivity of the nervous system to pain.

Nutrition Assessment, Interventions, and Monitoring for Patients with Celiac Disease: An Evidence Analysis Center Scoping Review

The objectives of this scoping review were to identify and characterize studies examining nutrition assessment, interventions, and measures to monitor gluten-free diet (GFD) adherence/compliance in patients with celiac disease (CD). An electronic literature search of four databases (Cochrane Database for systematic reviews, CINAHL, Embase, and Ovid MEDLINE) was conducted to identify articles examining nutrition care in CD individuals. Except for narrative review, grey literature, and case study/report, all types of peer-reviewed articles published between January 2007 and August 2018 were eligible. There were a total of 10,823 records; 10,368 were excluded during the first round of screening due to irrelevancy and/or duplication. Of the 455 full-text articles that were assessed, 292 met the criteria and were included. Most of the studies were observational studies (n=212), followed by experimental trials (n=50), evidence-based practice guideline (EBPG)/report/statement (n=16), and systematic review (SR) (n=14). Nine original studies examined assessment, focusing mainly on different tools/ways to assess GFD adherence. The majority of the included original articles (n=235) were in the nutrition intervention category with GFD, oats, and prebiotics/probiotics as the top-three most studied interventions. There were eight SRs on GFD and five on oats. One SR and 21 original studies investigated the effectiveness of different measures to monitor GFD adherence/compliance. Although recent CD EBPGs were identified, different methods with varying levels of rigor, in terms of literature search and assessment of evidence strength, were used. Based on this scoping review, interventions focused on gluten-free diet and oats have been significantly covered by either SRs or EBPGs. Studies related to prebiotics/probiotics and education program/counseling focused interventions, as well as assessment, in CD patients have increased in recent years. Thus, it might be beneficial to conduct SRs/EBPGs focused on these topics to guide practitioners.

Mass Spectrometric Analysis of L-carnitine and its Esters: Potential Biomarkers of Disturbances in Carnitine Homeostasis

PURPOSE

After a golden age of classic carnitine research three decades ago, the spread of mass spectrometry opened new perspectives and a much better understanding of the carnitine system is available nowadays. In the classic period, several human and animal studies were focused on various distinct physiological functions of this molecule and these revealed different aspects of carnitine homeostasis in normal and pathological conditions. Initially, the laboratory analyses were based on the classic or radioenzymatic assays, enabling only the determination of free and total carnitine levels and calculation of total carnitine esters' amount without any information on the composition of the acyl groups. The introduction of mass spectrometry allowed the measurement of free carnitine along with the specific and sensitive determination of different carnitine esters. Beyond basic research, mass spectrometry study of carnitine esters was introduced into the newborn screening program because of being capable to detect more than 30 metabolic disorders simultaneously. Furthermore, mass spectrometry measurements were performed to investigate different disease states affecting carnitine homeostasis, such as diabetes, chronic renal failure, celiac disease, cardiovascular diseases, autism spectrum disorder or inflammatory bowel diseases.

RESULTS

This article will review the recent advances in the field of carnitine research with respect to mass spectrometric analyses of acyl-carnitines in normal and various pathological states.

CONCLUSION

The growing number of publications using mass spectrometry as a tool to investigate normal physiological conditions or reveal potential biomarkers of primary and secondary carnitine deficiencies shows that this tool brought a new perspective to carnitine research.

Characterizing acyl-carnitine biosignatures for schizophrenia: a longitudinal pre- and post-treatment study

Subjects with schizophrenia have high risks of metabolic abnormalities and bioenergetic dysfunction. Acyl-carnitines involved in bioenergetic pathways provide potential biomarker targets for identifying early changes and onset characteristics in subjects with schizophrenia. We measured 29 acyl-carnitine levels within well-characterized plasma samples of adults with schizophrenia and healthy controls using liquid chromatography-mass spectrometry (LC-MS). Subjects with schizophrenia were measured at baseline and after 8 weeks of treatment. A total of 225 subjects with schizophrenia and 175 age- and gender-matched healthy controls were enrolled and 156 subjects completed the 8-week follow-up. With respect to plasma acyl-carnitines, the individuals with schizophrenia at baseline showed significantly higher levels of C4-OH (C3-DC) and C16:1, but lower concentrations of C3, C8, C10, C10:1, C10:2, C12, C14:1-OH, C14:2, and C14:2-OH when compared with healthy controls after controlling for age, sex, body mass index (BMI), smoking, and drinking. For the comparison between pretreatment and posttreatment subjects, all detected acyl-carnitines were significantly different between the two groups. Only the concentration of C3 and C4 were increased after selection by variable importance in projection (VIP) value >1.0 and false discovery rate (FDR) q value <0.05. A panel of acyl-carnitines were selected for the ability to differentiate subjects of schizophrenia at baseline from controls, pre- from post-treatment, and posttreatment from controls. Our data implicated acyl-carnitines with abnormalities in cellular bioenergetics of schizophrenia. Therefore, acyl-carnitines can be potential targets for future investigations into their roles in the pathoetiology of schizophrenia.

Fatigue as an Extra-Intestinal Manifestation of Celiac Disease: A Systematic Review

Celiac disease may present with a range of different symptoms, including abdominal problems in a broader sense, iron deficiency and “constant tiredness”. All of these symptoms should consequently lead the clinicians to consider celiac disease as a potential etiopathogenetic cause. Although the pathophysiology of celiac disease is well documented, the actual mechanisms for disease presentation(s) are less well understood. We here address the topic of fatigue in celiac disease. A systematic literature search identified 298 papers of which five met the criteria for full evaluation. None of the reviewed papers were of high quality and had several methodological weaknesses. We conclude that there is an unmet need to study the contributing factors and management of fatigue in celiac disease.

Low testosterone in non-responsive coeliac disease: A case series, case-control study with comparisons to the National Health and Nutrition Examination Survey

BACKGROUND

Adults with coeliac disease (CD) often report persistent fatigue, even when CD appears well controlled for unknown reasons.

AIMS

To evaluate common indications for testosterone panel (TP) testing and prevalence of low testosterone (T) in CD.

METHODS

In our case series, we determined common indications for checking TP in CD. Next, we conducted a case-control study to compare TP in CD vs. healthy controls (HC). We compared mean total T (TT), free T (FT) based on serologic, histologic disease activity. Finally, we assessed TT in tissue transglutaminase (tTG)+ vs. tTG- subjects and CD vs. HC obtained from the National Health and Nutrition Examination Survey (NHANES).

RESULTS

53 coeliac males had TP tested. Common indications included osteoporosis and fatigue. Low FT was observed in 7/13 men with osteoporosis and 5/6 with fatigue. In our case-control study (n=26 each), there was no difference in mean TT or FT between CD vs. HC, tTG+ vs tTG- or Marsh 0 vs. Marsh 3 groups. NHANES data showed no difference in mean TT between tTG+ vs tTG- (n=16 each) or CD vs. HC subjects (n=5 each).

CONCLUSIONS

Low T occurs in CD patients at a similar rate as the general population. Common presentations of low T may mimic non-responsive CD symptoms.

Systematic review: patient-reported outcome measures in coeliac disease for regulatory submissions

BACKGROUND

New therapeutics are moving into phase 3 clinical trials for the treatment of coeliac disease, a condition with no established therapies other than gluten-free diet. These trials will require a meaningful, validated and fit for purpose patient-reported outcome measure (PROM) to quantify the symptomatic improvement of patients.

AIM

To evaluate existing PROMs for suitability in a Food and Drug Administration (FDA) approval trial for a coeliac disease therapeutic.

METHOD

We performed a systematic search in five online databases (MedLine, EmBase, Web of Science, CENTRAL, CINAHL) for studies that enrolled patients with coeliac disease and used PROMs. Studies included in this review had to measure some PROM concept, be patient administered and based upon a previously validated instrument with published measurement properties.

RESULTS

Our literature search identified 2706 unique records of which 199 ultimately qualified for abstraction. The majority of PROMs used in studies of coeliac disease was generic and did not measure numerous symptoms or concerns of interest to patients. Four PROMs were found to contain appropriate content for use in an FDA trial: the coeliac disease-specific modification of the Gastrointestinal Symptoms Rating Scale (CeD-GSRS), Psychological General Well-Being Index (PGWB), the Celiac Disease Symptom Diary (CDSD) and the Celiac Disease Patient Reported Outcome (CeD-PRO). The GSRS and PGWB are most often used together and are two of the most extensively used measures in coeliac disease. The CDSD and CeD-PRO were developed exclusively for trials in coeliac disease but have much less published information on their measurement properties.

CONCLUSIONS

While we did not find PROMs that currently meet the stated expectations of the FDA for regulatory purposes, four PROMs (CeD-GSRS, PGWB, CDSD and CeD-PRO) appear to contain appropriate content and with modest additional validation work could meet scientific standards for valid and sensitive measures of disease and treatment outcome. Specifically, what is needed for these instruments is an understanding of how sensitive they are to real changes in-patient condition, how stable they are over a period of time when health status should not have changed (test-retest reliability) as well as how they correlate with other measures of patient functioning such as intestinal biopsy. All of these objectives could feasibly be accomplished over a short cohort study of patients with biopsy-defined coeliac disease undergoing gluten challenge.

Bones of contention: bone mineral density recovery in celiac disease--a systematic review

Metabolic bone disease is a frequent co-morbidity in newly diagnosed adults with celiac disease (CD), an autoimmune disorder triggered by the ingestion of dietary gluten. This systematic review of studies looked at the efficacy of the gluten-free diet, physical activity, nutrient supplementation, and bisphosphonates for low bone density treatment. Case control and cohort designs were identified from PubMed and other academic databases (from 1996 to 2015) that observed newly diagnosed adults with CD for at least one year after diet treatment using the dual-energy x-ray absorptiometry (DXA) scan. Only 20 out of 207 studies met the inclusion criteria. Methodological quality was assessed using the Strengthening of the Reporting of Observational Studies in Epidemiology (STROBE) statement checklist. Gluten-free diet adherence resulted in partial recovery of bone density by one year in all studies, and full recovery by the fifth year. No treatment differences were observed between the gluten-free diet alone and diet plus bisphosphonates in one study. For malnourished patients, supplementation with vitamin D and calcium resulted in significant improvement. Evidence for the impact of physical activity on bone density was limited. Therapeutic strategies aimed at modifying lifestyle factors throughout the lifespan should be studied.

Psychological morbidity of celiac disease: A review of the literature

BACKGROUND

Celiac disease has been linked to decreased quality of life and certain mood disorders. The effect of the gluten free diet on these psychological aspects of the disease is still unclear.

OBJECTIVES

The objective of this article is to review the literature on psychological morbidity of celiac disease.

METHODS

We performed a PubMed search for the time period from 1900 until June 1, 2014, to identify papers on psychological aspects of celiac disease looking specifically at quality of life, anxiety, depression and fatigue.

RESULTS

Anxiety, depression and fatigue are common complaints in patients with untreated celiac disease and contribute to lower quality of life. While aspects of these conditions may improve within a few months after starting a gluten-free diet, some patients continue to suffer from significant psychological morbidity. Psychological symptoms may affect the quality of life and the dietary adherence.

CONCLUSION

Health care professionals need to be aware of the ongoing psychological burden of celiac disease in order to support patients with this disease.

A review of current evidence for acetyl-l-carnitine in the treatment of depression

Despite numerous antidepressants available, many patients with depression do not achieve adequate response rendering needs for novel antidepressants with different mechanism of actions. Acetyl-l-carnitine (ALC) is a potential antidepressant with novel mechanism of action because of its diverse functions related with neuroplasticity. Animal and cellular models suggest that ALC's neuroplasiticity effect, membrane modulation, and neurotransmitter regulation may play an important role in treatment of depression. Four randomized clinical studies (RCT) demonstrated the superior efficacy of ALC over placebo (PBO) in patients with depression. Two RCTs showed its superior efficacy over PBO in dysthymic disorder, and 2 other RCTs showed that it is equally effective as fluoxetine and amisulpride in treatment of dysthymic disorder. ALC was also effective in improving depressive symptoms in patients with fibromyalgia and minimal hepatic encephalopathy. It was also found to be equally tolerable to PBO and better tolerable than fluoxetine and amisulpride. In conclusion, ALC may be potentially effective and tolerable next treatment option with novel action mechanisms for patients with depression, in particular older population and patients with comorbid medical conditions who are vulnerable to adverse events from antidepressants. However, more clinical trial data with adequately-powered, well-designed and advanced methodology will be mandatory to conclude whether ALC as a monotherapy or augmentation agent may be efficacious and clinically beneficial for depression.

Risk of idiopathic dilated cardiomyopathy in 29 000 patients with celiac disease

Background

Dilated cardiomyopathy (DCM) is a rare disease of largely unknown origin. Previous studies have suggested an increased prevalence of celiac disease (CD) in patients with DCM. These studies, however, were based on a maximum of 5 patients with both CD and DCM. In the present large Swedish population-based cohort study, we examined the risk of idiopathic DCM in patients with CD determined by small-intestinal histopathology.

Methods and Results

From 2006 to 2008, we collected duodenal/jejunal biopsy data on CD (equal to villous atrophy, Marsh stage 3, n=29 071 unique individuals) from (all) 28 pathology departments in Sweden. These individuals were compared with 144 429 reference individuals matched for age, sex, calendar year, and county. Data on DCM were obtained through the National Patient Register and confirmed by patient charts and echocardiography data. During follow-up, 17 patients with CD and 52 reference individuals developed idiopathic DCM. Thus, patients with CD were at an increased risk of idiopathic DCM (hazard ratio, 1.73; 95% confidence interval, 1.00 to 3.00), although the risk estimate failed to attain statistical significance (P=0.052).

Conclusion

This nationwide study found a moderately but not statistically significantly increased risk of idiopathic DCM in patients with biopsy-verified CD. (J Am Heart Assoc. 2012;1:e001594 doi: 10.1161/JAHA.112.001594.)

Carnitine for fatigue in multiple sclerosis

BACKGROUND

Fatigue is reported to occur in up to 92% of patients with multiple sclerosis (MS) and has been described as the most debilitating of all MS symptoms by 28% to 40% of MS patients.

OBJECTIVES

To assess whether carnitine (enteral or intravenous) supplementation can improve the quality of life and reduce the symptoms of fatigue in patients with MS-related fatigue and to identify any adverse effects of carnitine when used for this purpose.

SEARCH METHODS

A literature search was performed using Cochrane MS Group Trials Register (09 September 2011), Cochrane Central Register of Controlled Trials (CENTRAL) "The Cochrane Library 2011, issue 3", MEDLINE (PubMed) (1966-09 September 2011), EMBASE (1974-09 September 2011), and www.clinicaltrials.gov for ongoing trials retrieval. Reference lists of review articles and primary studies were also screened. A hand search of the abstract book of recent relevant conference symposia was also conducted. Personal contact with MS experts and a manufacturer (Source Naturals, United States) of carnitine formulation was contacted to determine if they knew of other clinical trials. No language restrictions were applied.

SELECTION CRITERIA

Full reports of published and unpublished randomized controlled trials and quasi-randomized trials of any carnitine intervention in adults affected by multiple sclerosis with a clinical diagnosis of fatigue associated with multiple sclerosis were included.

DATA COLLECTION AND ANALYSIS

Data from the eligible trials was extracted and coded using a standardized data extraction form and entered into RevMan 5. Discrepancies were to be resolved by discussion with a third reviewer, however this was not necessary.The quality items to be assessed were method of randomization, allocation concealment, blinding (participants, investigators, outcome assessors and data analysis), intention-to-treat analysis and completeness of follow up.

MAIN RESULTS

The search identified one ongoing randomized, placebo-controlled, cross-over trial (expected completion 2013) and one completed randomized, active-comparator, cross-over trial. In the completed study, adult patients with relapsing-remitting and secondary progressive MS were exposed to both acetyl L-carnitine 2 grams daily and amantadine 200 mg daily The effects of carnitine on fatigue are unclear. There was no difference between carnitine and amantadine for the number of patients withdrawing from the study due to an adverse event (relative risk ratio 0.20; 95% confidence interval 0.03 to 1.55) and no patients experienced a serious adverse event in either treatment group. Mortality and quality of life were not reported.

AUTHORS' CONCLUSIONS

There is insufficient evidence that carnitine for the treatment of MS-related fatigue offers a therapeutic advantage over placebo or active comparators. Results of the ongoing trial are eagerly anticipated in order to provide clarity.

Investigation of electroacupuncture and manual acupuncture on carnitine and glutathione in muscle

Electroacupuncture (EA) and manual acupuncture (MA) have therapeutic effects on muscle fatigue in muscle disease. The deficiencies of carnitine and glutathione induce muscle fatigue. This report investigated the effects of EA and MA on carnitine and glutathione in muscle. After the mice of EA group were fixed in the animal cage, right Zusanli (ST36) and Jiexi (ST41) were acupunctured and stimulated with uniform reinforcing and reducing method by twirling the acupuncture needle for 15 min. And then, the needle handles were connected to an electric stimulator for stimulating the acupoint with dense-sparse waves. After the mice of MA group were fixed in an animal cage, right ST36 and ST41 were acupunctured and allowed for 15 min. The mice of normal control group were not acupunctured and stimulated for 15 min. The mice of all groups were killed for collecting muscle tissue 1 h after the final treatment. Carnitine and glutathione in homogenate of muscle tissue were determined with carnitine (Kainos Laboratories Co., Tokyo, Japan) and glutathione assay kit (Dojin Chemicals Co., Kumamoto, Japan). Carnitine level in muscle tissue of MA group was significantly higher than those of EA group and normal control group. Carnitine level in muscle tissue of EA group was not significantly different from that of normal control group. Glutathione levels in muscle tissue of EA group and MA group were significantly higher than that of normal control group. This report presented that carnitine in muscle is increased by MA, and not increased by EA, and that glutathione in muscle is increased by EA and MA.

Plasma carnitine is associated with fatigue in chronic hepatitis C but not in the irritable bowel syndrome

BACKGROUND

Fatigue is an important determinant of altered quality of life in patients affected by chronic hepatitis C or the irritable bowel syndrome (IBS).

AIM

In this study, we aimed at determining the contributory role of plasma levels of leptin and carnitine on fatigue in chronic hepatitis C and IBS.

METHODS

We enrolled 81 patients with chronic hepatitis C, 42 with IBS and 44 healthy subjects. Fatigue was evaluated using the Fatigue Impact Scale questionnaire. Body composition was assessed through impedance analysis. Plasma carnitine and leptin were measured.

RESULTS

Fatigue scores were significantly more elevated in patients with chronic hepatitis C and IBS than in healthy subjects. Patients with chronic hepatitis C but not IBS, had significant lower plasma levels of total and free carnitine adjusted for fat mass compared with healthy subjects. In patients with chronic hepatitis C and not with IBS, fatigue scores were negatively correlated with plasma levels of carnitine. Levels of free carnitine were significantly and independently associated with the severity of fatigue in patients with chronic hepatitis C [OR=2.019, P=0.02, CI 95% (1.01-1.23)].

CONCLUSIONS

In patients with chronic hepatitis C, the severity of fatigue is associated with a low level of carnitine, suggesting that an oral supplementation may be effective to relieve fatigue in chronic hepatitis C. The underlying mechanism of fatigue in IBS does not seem to involve carnitine.

Colon OCTN2 gene expression is up-regulated by peroxisome proliferator-activated receptor gamma in humans and mice and contributes to local and systemic carnitine homeostasis

In the large intestine organic cation transporter type-2 (OCTN2) is recognized as a transporter of compounds such as carnitine and colony sporulation factor, promoting health of the colon intestinal epithelium. Recent reports suggest that OCTN2 expression in small intestine is under control of peroxisome proliferator-activated receptor-alpha (PPARalpha). However, PPARalpha contribution to colonic OCTN2 expression remains controversial. Here we examined the transcriptional regulation of colon OCTN2 gene by PPARgamma. To exclude any additional modulation of other PPAR to OCTN2 expression, we used both in vivo and in vitro PPAR-null models and specific PPAR inhibitors. The PPARgamma agonists thiazolidinediones increased both OCTN2 mRNA and protein expression in colonic epithelial cell lines independently by PPARalpha expression. The induction was blocked only by PPARgamma antagonists or by gammaORF4, a PPARgamma isoform with dominant negative activity, suggesting a PPARgamma-dependent mechanism. A conserved noncanonical PPAR-responsive element was found by computational analysis in the first intron of human OCTN2 gene and validated by EMSA assay. Promoter-reporter assays further confirmed transcriptional functionality of the putative PPAR response element, whereas selective mutation caused complete loss of responsiveness to PPARgamma activation. Finally, adenovirus-mediated overexpression of constitutively active PPARgamma mutant increased colon OCTN2 expression in PPARalpha(-/-) mice. Interestingly, animals overexpressing colon PPARgamma showed a significant increase in plasma carnitine, thus demonstrating the functional contribution of large intestine to systemic carnitine homeostasis. This study reveals a PPARgamma-dependent absorption machinery in colon that is likely involved in the health of colon epithelium, in the microbiota-host interactions and in the absorption of nutraceuticals and drugs.

Carnitine for fatigue in multiple sclerosis

BACKGROUND

Fatigue is reported to occur in up to 92% of patients with multiple sclerosis (MS) and has been described as the most debilitating of all MS symptoms by 28% to 40% of MS patients.

OBJECTIVES

To assess whether carnitine (enteral or intravenous) supplementation can improve the quality of life and reduce the symptoms of fatigue in patients with MS-related fatigue and to identify any adverse effects of carnitine when used for this purpose.

SEARCH STRATEGY

A literature search was performed using Cochrane MS Group Trials Register (21 May 2009), Cochrane Central Register of Controlled Trials (CENTRAL) "The Cochrane Library 2009, issue 2, MEDLINE (PubMed) (1966-21 May 2009), EMBASE (1974-21 May 2009). Reference lists of review articles and primary studies were also screened. A hand search of the abstract book of recent relevant conference symposia was also conducted. Personal contact with MS experts and a manufacturer (Source Naturals, United States) of carnitine formulation was contacted to determine if they knew of other clinical trials. No language restrictions were applied.

SELECTION CRITERIA

Full reports of published and unpublished randomized controlled trials and quasi-randomized trials of any carnitine intervention in adults with a clinical diagnosis of fatigue associated with multiple sclerosis were included.

DATA COLLECTION AND ANALYSIS

Data from the eligible trials was extracted and coded using a standardized data extraction form and entered into RevMan 5. Discrepancies were to be resolved by discussion with a third reviewer however this was not necessary. The quality items to be assessed were method of randomization, allocation concealment, blinding (participants, investigators, outcome assessors and data analysis), intention-to-treat analysis and completeness of follow up.

MAIN RESULTS

The search identified one randomized cross-over trial. In this study patients were exposed to both acetyl L-carnitine (ALCAR(tm)) 2 grams daily and amantadine 200 mg daily in adult patients with relapsing-remitting and secondary progressive MS. The effects of carnitine on fatigue are not clear based on the one included crossover RCT. There was no difference between carnitine and amantadine for the number of patients withdrawing from the study due to an adverse event (relative risk ratio 0.20; 95% confidence interval 0.03 to 1.55. Mortality, serious adverse events, total adverse events, and quality of life were not reported.

AUTHORS' CONCLUSIONS

There is insufficient evidence that carnitine for the treatment of MS-related fatigue offers a therapeutic advantage over placebo or active comparators.

Recent advances in coeliac disease

PURPOSE OF REVIEW

Worldwide awareness of coeliac disease in all ages continues to grow. This article aims to summarize critically the recent research advances in coeliac disease.

RECENT FINDINGS

Large multicentre studies have provided further evidence of the role of environmental and nonhuman leucocyte antigen genetic factors in coeliac disease. Siblings of coeliac patients carry a high risk, but those found to have negative coeliac serology are very unlikely to develop the disease. Advances in the efficacy of serological antibody testing potentiate the possibility of future accurate screening programmes in the community. Adherence to a gluten-free diet remains paramount as the recognition of coeliac related complications increases.

SUMMARY

Despite the encouraging progress that has taken place in our genetic and immunological knowledge of coeliac disease, early introduction of a gluten-free diet remains the cornerstone of treatment. Alternatives, however, aimed at altering the toxicity of cereal proteins are now looking more promising.

The metabonomic signature of celiac disease

Celiac disease (CD) is a multifactorial disorder involving genetic and environmental factors, thus, having great potential impact on metabolism. This study aims at defining the metabolic signature of CD through Nuclear Magnetic Resonance (NMR) of urine and serum samples of CD patients. Thirty-four CD patients at diagnosis and 34 healthy controls were examined by (1)H NMR of their serum and urine. A CD patients' subgroup was also examined after a gluten-free diet (GFD). Projection to Latent Structures provided data reduction and clustering, and Support Vector Machines provided pattern recognition and classification. The classification accuracy of CD and healthy control groups was 79.7-83.4% for serum and 69.3% for urine. Sera of CD patients were characterized by lower levels (P < 0.01) of several metabolites such as amino acids, lipids, pyruvate and choline, and by higher levels of glucose and 3-hydroxybutyric acid, while urines showed altered levels (P < 0.05) of, among others, indoxyl sulfate, meta-[hydroxyphenyl]propionic acid and phenylacetylglycine. After 12 months of GFD, all but one of the patients were classified as healthy by the same statistical analysis. NMR thus reveals a characteristic metabolic signature of celiac disease. Altered serum levels of glucose and ketonic bodies suggest alterations of energy metabolism, while the urine data point to alterations of gut microbiota. Metabolomics may thus provide further hints on the biochemistry of the disease.