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1.
BMJ Open ; 12(9): e061080, 2022 09 19.
Article En | MEDLINE | ID: mdl-36123082

OBJECTIVES: Although inherited retinal disorders (IRDs) related to the gene encoding the retinal pigment epithelium 65kD protein (RPE65) significantly impact the vision-related quality of life (VRQoL), their emotional and social aspects remain poorly investigated in Italy. Narrative Medicine (NM) reveals the more intimate aspects of the illness experience, providing insights into clinical practice. DESIGN AND SETTING: This NM project was conducted in Italy between July and December 2020 and involved five eye clinics specialised in IRDs. Illness plots and parallel charts, together with a sociodemographic survey, were collected through the project's website; remote in-depth interviews were also conducted. Narratives and interviews were analysed through NVivo software and interpretive coding. PARTICIPANTS: 3 paediatric and 5 adult patients and eight caregivers participated in the project; 11 retinologists globally wrote 27 parallel charts; 5 professionals from hospital-based multidisciplinary teams and one patient association member were interviewed. RESULTS: Findings confirmed that RPE65-related IRDs impact VRQoL in terms of activities and mobility limitations. The emotional aspects emerged as crucial in the clinical encounter and as informative on IRD management challenges and real-life experiences, while psychological support was addressed as critical from clinical diagnosis throughout the care pathway for both patients and caregivers; the need for an IRDs 'culture' emerged to acknowledge these conditions, and therefore, promoting diversity within society. CONCLUSIONS: The project was the first effort to investigate the impact of RPE65-related IRDs on the illness experience through NM, concomitantly addressing the perspectives of paediatric and adult patients, caregivers and healthcare professionals and provided preliminary insights for the knowledge of RPE65-related IRDs and the clinical practice.


Narrative Medicine , Retinal Diseases , Adult , Caregivers/psychology , Child , Emotions , Humans , Quality of Life/psychology , Vision Disorders
2.
Clin Ophthalmol ; 15: 4591-4605, 2021.
Article En | MEDLINE | ID: mdl-34880596

PURPOSE: Timely detection and multidisciplinary management of RPE65-related inherited retinal disorders (IRDs) can significantly improve both disease management and patient care. Thus, this Narrative Medicine (NM) project aimed to investigate the evolution of the care pathway and the expectations on genetic counseling and gene therapy by patients, caregivers, and healthcare professionals. PATIENTS AND METHODS: This project was conducted between July and December 2020, involving five Italian eye clinics specialized in IRDs, targeted pediatric and adult patients, their caregivers, attending retinologists and multidisciplinary healthcare professionals. Narratives and parallel charts, together with a sociodemographic survey, were collected through the project webpage. In-depth interviews were conducted with Patient Association (PA) members and multidisciplinary healthcare professionals. All data were entered into the Nvivo Software for coding and analysis. RESULTS: Three pediatric and five adult patients with early-onset RPE65-related IRDs as well as eight caregivers were enrolled; 11 retinologists globally wrote 27 parallel charts; in-depth interviews were done with five multidisciplinary healthcare professionals and one PA member. Early diagnosis remains challenging, and patients reported to have changed up to 10 healthcare professionals before accessing their specialized center. Despite the oftentimes lack of awareness of patients and caregivers on the purpose of genetic testing, participants generally consider gene therapy as a therapeutic chance and a historic breakthrough for the management of RPE65-related IRDs. Well-organized networks to support the patient's referral to specialized centers - as well as a proper communication of the clinical and genetic diagnosis and the multidisciplinary approach - emerge as crucial aspects in facilitating an early diagnosis and management and a timely initiation of the rehabilitation pathway. CONCLUSION: The project investigated the RPE65-related IRDs care pathway while integrating the different perspectives involved through NM. The analysis explored the patient's pathway in Italy and confirmed the need for a well-organized network and multidisciplinary care while highlighting several preliminary areas of improvement in the management of RPE65-related IRDs.

3.
Int J Mol Sci ; 22(13)2021 Jul 05.
Article En | MEDLINE | ID: mdl-34281261

Inherited retinal diseases (IRDs) are a heterogeneous group of conditions that include retinitis pigmentosa (RP) and Leber congenital amaurosis (LCA) and early-onset severe retinal dystrophy (EO[S]RD), which differ in severity and age of onset. IRDs are caused by mutations in >250 genes. Variants in the RPE65 gene account for 0.6-6% of RP and 3-16% of LCA/EORD cases. Voretigene neparvovec is a gene therapy approved for the treatment of patients with an autosomal recessive retinal dystrophy due to confirmed biallelic RPE65 variants (RPE65-IRDs). Therefore, the accurate molecular diagnosis of RPE65-IRDs is crucial to identify 'actionable' genotypes-i.e., genotypes that may benefit from the treatment-and is an integral part of patient management. To date, hundreds of RPE65 variants have been identified, some of which are classified as pathogenic or likely pathogenic, while the significance of others is yet to be established. In this review, we provide an overview of the genetic diagnostic workup needed to select patients that could be eligible for voretigene neparvovec treatment. Careful clinical characterization of patients by multidisciplinary teams of experts, combined with the availability of next-generation sequencing approaches, can accelerate patients' access to available therapeutic options.


Eye Diseases, Hereditary/genetics , Retinal Diseases/genetics , cis-trans-Isomerases/genetics , Eye Diseases, Hereditary/diagnosis , Eye Diseases, Hereditary/therapy , Genetic Counseling , Genetic Testing/methods , Genetic Therapy , Genetic Variation , Genotype , Humans , Mutation , Retinal Diseases/diagnosis , Retinal Diseases/therapy
4.
Nutrients ; 10(11)2018 Nov 03.
Article En | MEDLINE | ID: mdl-30400275

Pentadecanoic acid (C15:0) and heptadecanoic acid (C17:0) have been described as dietary biomarkers of dairy-fat consumption, with varying degrees of reliability between studies. It remains unclear how the total amount of dietary fat, representing one of the main confounding factors in these biomarker investigations, affects C15:0 and C17:0 circulating concentrations independent of their relative intake. Additionally, it is not clear how changes in the dietary total-fat affects other fatty acids in circulation. Through two dietary studies with different total-fat levels but maintaining identical fatty acid compositions, we were able to see how the dietary total-fat affects the fatty acids in circulation. We saw that there was a statistically significant, proportionate, and robust decrease in the endogenous C15:0 levels with an increase in dietary total-fat. However, there was no significant change in the circulating C17:0 concentrations as the total-fat increased. To conclude, the dietary total-fat content and fat-type have a very complex influence on the relative compositions of circulating fatty acids, which are independent of the actual dietary fatty acid composition. Knowing how to manipulate circulating C15:0 and C17:0 concentrations is far-reaching in nutritional/pathological research as they highlight a dietary route to attenuate the development of metabolic disease (both by reducing risk and improving prognosis).


Dietary Fats/administration & dosage , Fatty Acids/blood , Animals , Biomarkers , Diet , Fatty Acids/administration & dosage , Gas Chromatography-Mass Spectrometry , Male , Rats , Rats, Sprague-Dawley , Rats, Wistar
5.
Mol Genet Metab ; 121(2): 180-189, 2017 06.
Article En | MEDLINE | ID: mdl-28456385

Pantothenate Kinase-Associated Neurodegeneration (PKAN) is a form of Neurodegeneration with Brain Iron Accumulation (NBIA) associated with mutations in the pantothenate kinase 2 gene (PANK2). The PANK2 catalyzes the first step of coenzyme A (CoA) biosynthesis, a pathway producing an essential cofactor that plays a key role in energy and lipid metabolism. The majority of PANK2 mutations reduces or abolishes the activity of the enzyme. In around 10% of cases with PKAN, the presence of deformed red blood cells with thorny protrusions in the circulation has been detected. Changes in membrane protein expression and assembly during erythropoiesis were previously explored in patients with PKAN. However, data on red blood cell membrane phospholipid organization are still missing in this disease. In this study, we performed lipidomic analysis on red blood cells from Italian patients affected by PKAN with a particular interest in membrane physico-chemical properties. We showed an increased number of small red blood cells together with membrane phospholipid alteration, particularly a significant increase in sphingomyelin (SM)/phosphatidylcholine (PC) and SM/phosphatidylethanolamine (PE) ratios, in subjects with PKAN. The membrane structural abnormalities were associated with membrane fluidity perturbation. These morphological and functional characteristics of red blood cells in patients with PKAN offer new possible tools in order to shed light on the pathogenesis of the disease and to possibly identify further biomarkers for clinical studies.


Erythrocyte Membrane/chemistry , Membrane Lipids/blood , Pantothenate Kinase-Associated Neurodegeneration/blood , Pantothenate Kinase-Associated Neurodegeneration/physiopathology , Phospholipids/blood , Adult , Biomarkers/blood , Brain/diagnostic imaging , Brain/pathology , Child , Erythrocyte Membrane/physiology , Female , Humans , Iron/metabolism , Magnetic Resonance Imaging , Male , Membrane Fluidity , Membrane Lipids/chemistry , Membrane Proteins/genetics , Mitochondria/enzymology , Mitochondria/ultrastructure , Mutation , Pantothenate Kinase-Associated Neurodegeneration/genetics , Phospholipids/chemistry , Young Adult
6.
Biochim Biophys Acta ; 1847(10): 1025-35, 2015 Oct.
Article En | MEDLINE | ID: mdl-26028302

Cardiolipin (CL), a unique mitochondrial phospholipid, plays a key role in several processes of mitochondrial bioenergetics as well as in mitochondrial membrane stability and dynamics. The present study was designed to determine the effect of MitoQ, a mitochondrial-targeted antioxidant, on the content of liver mitochondrial membrane phospholipids, in particular CL, and its fatty acid composition in obesogenic diet-fed rats. To do this, twenty-four 6week old male Sprague Dawley rats were randomized into three groups of 8 animals and fed for 8weeks with either a control diet, a high fat diet (HF), or a HF diet with MitoQ (HF+MitoQ). Phospholipid classes and fatty acid composition were assayed by chromatographic methods in liver and liver mitochondria. Mitochondrial bioenergetic function was also evaluated. While MitoQ had no or slight effects on total liver fatty acid composition and phospholipid classes and their fatty acid composition, it had major effects on liver mitochondrial phospholipids and mitochondrial function. Indeed, MitoQ both increased CL synthase gene expression and CL content of liver mitochondria and increased 18:2n-6 (linoleic acid) content of mitochondrial phospholipids by comparison to the HF diet. Moreover, mitochondrial CL content was positively correlated to mitochondrial membrane fluidity, membrane potential and respiration, as well as to ATP synthase activity, while it was negatively correlated to mitochondrial ROS production. These findings suggest that MitoQ may decrease pathogenic alterations to CL content and profiles, thereby preserving mitochondrial function and attenuating the development of some of the features of metabolic syndrome in obesogenic diet-fed rats.

7.
Int J Biochem Cell Biol ; 63: 25-31, 2015 Jun.
Article En | MEDLINE | ID: mdl-25668476

Neurodegeneration with brain iron accumulation (NBIA) comprises a group of brain iron deposition syndromes that lead to mixed extrapyramidal features and progressive dementia. Exact pathologic mechanism of iron deposition in NBIA remains unknown. However, it is becoming increasingly evident that many neurodegenerative diseases are hallmarked by metabolic dysfunction that often involves altered lipid profile. Among the identified disease genes, four encode for proteins localized in mitochondria, which are directly or indirectly implicated in lipid metabolism: PANK2, CoASY, PLA2G6 and C19orf12. Mutations in PANK2 and CoASY, both implicated in CoA biosynthesis that acts as a fatty acyl carrier, lead, respectively, to PKAN and CoPAN forms of NBIA. Mutations in PLA2G6, which plays a key role in the biosynthesis and remodeling of membrane phospholipids including cardiolipin, lead to PLAN. Mutations in C19orf12 lead to MPAN, a syndrome similar to that caused by mutations in PANK2 and PLA2G6. Although the function of C19orf12 is largely unknown, experimental data suggest its implication in mitochondrial homeostasis and lipid metabolism. Altogether, the identified mutated proteins localized in mitochondria and associated with different NBIA forms support the concept that dysfunctions in mitochondria and lipid metabolism play a crucial role in the pathogenesis of NBIA. This article is part of a Directed Issue entitled: Energy Metabolism Disorders and Therapies.


Group VI Phospholipases A2/genetics , Iron Metabolism Disorders/genetics , Mitochondria/genetics , Mitochondrial Proteins/genetics , Phosphotransferases (Alcohol Group Acceptor)/genetics , Transferases/genetics , Brain/metabolism , Brain/pathology , Humans , Iron/metabolism , Iron Metabolism Disorders/pathology , Lipid Metabolism/genetics , Mitochondria/metabolism , Mitochondria/pathology , Mutation , Phospholipids/metabolism
8.
J Inherit Metab Dis ; 38(1): 123-36, 2015 Jan.
Article En | MEDLINE | ID: mdl-25300979

Neurodegeneration with brain iron accumulation (NBIA) is a group of devastating and life threatening rare diseases. Adult and early-onset NBIA syndromes are inherited as X-chromosomal, autosomal dominant or recessive traits and several genes have been identified as responsible for these disorders. Among the identified disease genes, only two code for proteins directly involved in iron metabolism while the remaining NBIA genes encode proteins with a wide variety of functions ranging from fatty acid metabolism and autophagy to still unknown activities. It is becoming increasingly evident that many neurodegenerative diseases are associated with metabolic dysfunction that often involves altered lipid metabolism. This is not surprising since neurons have a peculiar and heterogeneous lipid composition critical for the development and correct functioning of the nervous system. This review will focus on specific NBIA forms, namely PKAN, CoPAN, PLAN, FAHN and MPAN, which display an interesting link between neurodegeneration and alteration of phospholipids and sphingolipids metabolism, mitochondrial morphology and membrane remodelling.


Brain/metabolism , Iron Metabolism Disorders/metabolism , Iron/chemistry , Lipid Metabolism , Neuroaxonal Dystrophies/metabolism , Neurodegenerative Diseases/metabolism , Animals , Fatty Acids/metabolism , Humans , Iron Metabolism Disorders/genetics , Mitochondria/metabolism , Mixed Function Oxygenases/metabolism , Neuroaxonal Dystrophies/genetics , Neurodegenerative Diseases/genetics , Pantothenate Kinase-Associated Neurodegeneration/genetics , Pantothenate Kinase-Associated Neurodegeneration/metabolism , Phospholipids/metabolism , Sphingolipids/metabolism , Syndrome
9.
J Hepatol ; 62(2): 278-85, 2015 Feb.
Article En | MEDLINE | ID: mdl-25220251

BACKGROUND & AIMS: The metabolic identity of a hepatocyte is determined by its position along the porto-centrilobular axis of a liver lobule. Altered patterns of metabolic liver zonation are associated with several pathologies. In hepatitis C, although only a minority of hepatocytes harbour the virus, the liver undergoes major systemic metabolic changes. We have investigated the HCV-driven mechanisms that allow the systemic loss of metabolic zonation. METHODS: Transgenic mice with hepatocyte-targeted expression of all HCV proteins (FL-N/35 model) and needle biopsies from hepatitis C patients were studied with respect to patterns of lipid deposition in the context of metabolic zonation of the liver lobule. RESULTS: We report that low levels of viral proteins are sufficient to drive striking alterations of hepatic metabolic zonation. In mice, a major lipogenic enzyme, fatty acid synthase, was redistributed from its normal periportal expression into the midzone of the lobule, coinciding with a highly specific midzone accumulation of lipids. Strikingly, alteration of zonation was not limited to lipogenic enzymes and appeared to be driven by systemic signalling via the Wnt/ß-catenin pathway. Importantly, we show that similarly perturbed metabolic zonation appears to precede steatosis in early stages of human disease associated with HCV infection. CONCLUSIONS: Our results rationalize systemic effects on liver metabolism, triggered by a minority of infected cells, thus opening new perspectives for the investigation of HCV-related pathologies.


Hepacivirus/metabolism , Hepatitis C, Chronic/metabolism , Hepatocytes/metabolism , Liver/metabolism , Viral Proteins/metabolism , Animals , Biopsy, Needle , DNA, Viral/genetics , Disease Models, Animal , Hepacivirus/genetics , Hepatitis C, Chronic/pathology , Hepatitis C, Chronic/virology , Hepatocytes/pathology , Hepatocytes/virology , Humans , Liver/pathology , Liver/virology , Male , Mice , Mice, Transgenic
10.
J Food Sci ; 79(7): C1260-70, 2014 Jul.
Article En | MEDLINE | ID: mdl-24962212

UNLABELLED: Antioxidant activities of Myrtus communis leaf phenolic compounds (McPCs) were investigated on 2,2'-9-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS(+) •) and oxygen radical absorbance capacity (ORAC) tests or on oxidation of biological models, human low-density lipoprotein (LDL) and phospholipid aqueous dispersion (L-α-phosphatidylcholine stabilized by bile salts). Two extraction techniques, microwave-assisted (MAE) and conventional (CE), were used to isolate McPCs, producing similar results of phenolic compound content. ABTS(+) • assay showed clearly that myrtle extracts exhibited a stronger scavenging effect than butylated hydroxyanisole and α-tocopherol, with a slight advantage for myrtle CE extract. In ORAC assay, the both McPC extracts were similarly less effective than the pure compounds as caffeic acid and myricitrin (myricetin 3-O-rhamnoside) but stronger than butylated hydroxytoluene. Moreover, myrtle CE and MAE extracts, and myricitrin were able to inhibit similarly the production of conjugated dienes and to prolong the lag phase (Tlag) during Cu(2+)-induced LDL oxidation with a dose-response effect. The cryo-electron microscopy observations on studied phospholipid dispersion stabilized by bile salts (BS) revealed the presence of bilayer vesicles and micelles. In 2,2'-azobis (2-amidinopropane) hydrochloride-induced phospholipid/BS oxidation, myrtle CE and MAE extracts gave similar effects to α-tocopherol and caffeic acid but myricitrin showed a higher protective effect than myrtle extracts. We showed also that no synergic or additive effect between α-tocopherol and myrtle extracts or caffeic acid in α-tocopherol-enriched phospholipid/BS dispersion, but myricitrin showed an additive effect and thus promoted the total antioxidant activity. These data showed that myrtle extract could be used as potential natural antioxidants, food stabilizers, or natural health products. PRACTICAL APPLICATION: We show that microwave-assisted extraction could be an alternative method for plant phenolic compound recovery allowing important gain in time extraction.We report inhibition of low-density lipoprotein oxidation in vitro initiated by Cu(2+) ions. We report that myrtle extract may be a source of natural antioxidants to counteract phospholipid peroxidation as well as α-tocopherol.


Antioxidants/chemistry , Lipoproteins, LDL/chemistry , Myrtus/chemistry , Phenols/chemistry , Phospholipids/chemistry , Plant Leaves/chemistry , Humans , Oxidation-Reduction , Plant Extracts/pharmacology
11.
Br J Nutr ; 110(10): 1789-802, 2013 Nov.
Article En | MEDLINE | ID: mdl-23656726

The incidence of metabolic syndrome components including obesity, lipid deregulation, insulin resistance (IR) and non-alcoholic fatty liver disease is increasing rapidly in wealthy societies. The present study was designed to determine the effect of different nutritional lipid patterns (quantity and quality) on lipid utilisation and oxidative stress in the liver and muscle of rats in an integrated fashion. A total of forty-eight Wistar male rats were fed for 12 weeks with a mixed, lard or fish-oil diet, containing either 50 or 300 g lipid/kg. Rats developed liver steatosis associated with moderate liver injury when fed the 30% lipid diets, in spite of the absence of overt obesity or IR, except when fed the lard 30% lipid diet. The intake of the 30% lipid diets decreased hepatic lipogenesis and mitochondriogenesis and increased lipid peroxidation and protein oxidation. Surprisingly, muscle lipid content was not modified whatever the administered diet. The intake of the 30% lipid diets increased the muscle protein expression of fatty acid (FA) translocase/cluster of differentiation 36 (FAT/CD36), PPARg co-activator 1a (PGC-1a) and muscle carnitine palmitoyltransferase 1 (m-CPT1), reflecting increased FA transport in the muscle associated with increased oxidative metabolism. The lard 30% lipid diet led to IR without modifying the muscle lipid content. The fish-oil 30% lipid diet failed to prevent the development of hepatic steatosis and made the tissues more prone to oxidation. Overall, the present study suggests that the FA composition of muscle is more important than lipid accumulation itself in the modulation of insulin sensitivity, and indicates that precaution should be taken when advising an unphysiologically high (pharmacological) supplementation with long-chain n-3 PUFA.


Fatty Acids, Omega-3/pharmacology , Fatty Acids/pharmacology , Fatty Liver/metabolism , Insulin Resistance , Liver/metabolism , Muscle, Skeletal/metabolism , Oxidative Stress , Animals , Biological Transport/drug effects , CD36 Antigens/metabolism , Carnitine O-Palmitoyltransferase/metabolism , Diet , Dietary Fats/metabolism , Dietary Fats/pharmacology , Dietary Supplements , Fatty Acids/metabolism , Fatty Acids, Omega-3/metabolism , Fatty Liver/chemically induced , Fish Oils/metabolism , Fish Oils/pharmacology , Lipid Metabolism/drug effects , Lipid Peroxidation/drug effects , Male , Mitochondria , Muscle Proteins/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Protein Carbonylation/drug effects , Rats , Rats, Wistar , Transcription Factors/metabolism
12.
J Bioenerg Biomembr ; 44(4): 439-52, 2012 Aug.
Article En | MEDLINE | ID: mdl-22689144

No data are reported on changes in mitochondrial membrane phospholipids in non-alcoholic fatty liver disease. We determined the content of mitochondrial membrane phospholipids from rats with non alcoholic liver steatosis, with a particular attention for cardiolipin (CL) content and its fatty acid composition, and their relation with the activity of the mitochondrial respiratory chain complexes. Different dietary fatty acid patterns leading to steatosis were explored. With high-fat diet, moderate macrosteatosis was observed and the liver mitochondrial phospholipid class distribution and CL fatty acids composition were modified. Indeed, both CL content and its C18:2n-6 content were increased with liver steatosis. Moreover, mitochondrial ATP synthase activity was positively correlated to the total CL content in liver phospholipid and to CL C18:2n-6 content while other complexes activity were negatively correlated to total CL content and/or CL C18:2n-6 content of liver mitochondria. The lard-rich diet increased liver CL synthase gene expression while the fish oil-rich diet increased the (n-3) polyunsaturated fatty acids content in CL. Thus, the diet may be a significant determinant of both the phospholipid class content and the fatty acid composition of liver mitochondrial membrane, and the activities of some of the respiratory chain complex enzymes may be influenced by dietary lipid amount in particular via modification of the CL content and fatty acid composition in phospholipid.


Cardiolipins/metabolism , Dietary Fats/adverse effects , Fatty Liver/metabolism , Mitochondria, Liver/metabolism , Mitochondrial Membranes/metabolism , Animals , Dietary Fats/pharmacology , Fatty Liver/chemically induced , Fatty Liver/pathology , Male , Mitochondria, Liver/pathology , Mitochondrial Membranes/pathology , Mitochondrial Proton-Translocating ATPases/metabolism , Non-alcoholic Fatty Liver Disease , Rats , Rats, Wistar
13.
Chem Res Toxicol ; 25(3): 687-94, 2012 Mar 19.
Article En | MEDLINE | ID: mdl-22283477

Eicosapentaenoic acid (EPA) is a polyunsaturated fatty acid present in fish oils used for omega-3 enriched diets. The natural cis double bond geometry can be transformed to the trans configuration during the deodorization process utilized in the food industry. The analytical discrimination of the possible five monotrans regioisomers represents a limiting step for the recognition and structure-activity relationship in connection with the harmful effects of trans fatty acids in health. We carried out a dual synthetic strategy, providing new access to monotrans EPA isomers and valuable information on GC and NMR characteristics for further applications in metabolomics and lipidomics. This small library was used as an analytical reference for isomer determination in deodorized fish oils and the follow-up of rats fed fish oil diets, evidencing for the first time that monotrans EPA isomers are incorporated in liver mitochondrial membranes after dietary intake.


Eicosapentaenoic Acid/chemistry , Fish Oils/chemistry , Trans Fatty Acids/chemistry , Animals , Diet , Eicosapentaenoic Acid/pharmacokinetics , Fish Oils/pharmacokinetics , Isomerism , Mitochondria, Liver/metabolism , Phospholipids/metabolism , Rats , Trans Fatty Acids/pharmacokinetics , Tuna
14.
Br J Nutr ; 107(5): 647-59, 2012 Mar.
Article En | MEDLINE | ID: mdl-21774841

Dietary lipids are known to affect the composition of the biological membrane and functions that are involved in cell death and survival. The mitochondrial respiratory chain enzymes are membrane protein complexes whose function depends on the composition and fluidity of the mitochondrial membrane lipid. The present study aimed at investigating the impact of different nutritional patterns of dietary lipids on liver mitochondrial functions. A total of forty-eight Wistar male rats were divided into six groups and fed for 12 weeks with a basal diet, lard diet or fish oil diet, containing either 50 or 300 g lipid/kg. The 30 % lipid intake increased liver NEFA, TAG and cholesterol levels, increased mitochondrial NEFA and TAG, and decreased phospholipid (PL) levels. SFA, PUFA and unsaturation index (UI) increased, whereas MUFA and trans-fatty acids (FA) decreased in the mitochondrial membrane PL in 30 % fat diet-fed rats compared with 5 % lipid diet-fed rats. PL UI increased with fish oil diet v. basal and lard-rich diets, and PL trans-FA increased with lard diet v. basal and fish oil diets. The 30 % lipid diet intake increased mitochondrial membrane potential, membrane fluidity, mitochondrial respiration and complex V activity, and decreased complex III and IV activities. With regard to lipid quality effects, ß-oxidation decreased with the intake of basal or fish oil diets compared with that of the lard diet. The intake of a fish oil diet decreased complex III and IV activities compared with both the basal and lard diets. In conclusion, the characteristics and mitochondrial functions of the rat liver mitochondrial membrane are more profoundly altered by the quantity of dietary lipid than by its quality, which may have profound impacts on the pathogenesis and development of non-alcoholic fatty liver disease.


Diet, High-Fat/adverse effects , Mitochondria, Liver/metabolism , Mitochondrial Membranes/metabolism , Animals , Dietary Fats/administration & dosage , Dietary Fats/adverse effects , Dietary Fats/analysis , Electron Transport Complex III/metabolism , Electron Transport Complex IV/metabolism , Fatty Acids, Monounsaturated/administration & dosage , Fatty Acids, Monounsaturated/adverse effects , Fatty Acids, Monounsaturated/metabolism , Fatty Liver/etiology , Fish Oils/administration & dosage , Fish Oils/adverse effects , Fish Oils/chemistry , Male , Membrane Fluidity , Membrane Potential, Mitochondrial , Mitochondria, Liver/enzymology , Mitochondrial Membranes/enzymology , Mitochondrial Proton-Translocating ATPases/metabolism , Mitochondrial Trifunctional Protein , Multienzyme Complexes/metabolism , Oxidative Phosphorylation , Random Allocation , Rats , Rats, Wistar , Trans Fatty Acids/administration & dosage , Trans Fatty Acids/adverse effects , Trans Fatty Acids/metabolism
15.
Br J Nutr ; 106(4): 491-501, 2011 Aug.
Article En | MEDLINE | ID: mdl-21554810

Accumulation of muscle TAG content and modification of muscle phospholipid fatty acid pattern may have an impact on lipid metabolism, increasing the risk of developing diabetes. Some polyphenols have been reported to modulate lipid metabolism, in particular those issued from red grapes. The present study was designed to determine whether a grape polyphenol extract (PPE) modulates skeletal muscle TAG content and phospholipid fatty acid composition in high-fat-high-sucrose (HFHS) diet-fed rats. Muscle plasmalemmal and mitochondrial fatty acid transporters, GLUT4 and lipid metabolism pathways were also explored. The PPE decreased muscle TAG content in HFHS/PPE diet-fed rats compared with HFHS diet-fed rats and induced higher proportions of n-3 PUFA in phospholipids. The PPE significantly up-regulated GLUT4 mRNA expression. Gene and protein expression of muscle fatty acid transporter cluster of differentiation 36 (CD36) was increased in HFHS diet-fed rats but returned to control values in HFHS/PPE diet-fed rats. Carnitine palmitoyltransferase 1 protein expression was decreased with the PPE. Mitochondrial ß-hydroxyacyl CoA dehydrogenase was increased in HFHS diet-fed rats and returned to control values with PPE supplementation. Lipogenesis, mitochondrial biogenesis and mitochondrial activity were not affected by the PPE. In conclusion, the PPE modulated membrane phospholipid fatty acid composition and decreased muscle TAG content in HFHS diet-fed rats. The PPE lowered CD36 gene and protein expression, probably decreasing fatty acid transport and lipid accumulation within skeletal muscle, and increased muscle GLUT4 expression. These effects of the PPE are in favour of a better insulin sensibility.


Dietary Supplements , Fatty Acids/metabolism , Flavonoids/therapeutic use , Fruit/chemistry , Muscle, Skeletal/metabolism , Phenols/therapeutic use , Plant Extracts/therapeutic use , Vitis/chemistry , Animals , CD36 Antigens/genetics , CD36 Antigens/metabolism , Dietary Fats/adverse effects , Dietary Sucrose/adverse effects , Gene Expression Regulation , Glucose Transporter Type 4/genetics , Glucose Transporter Type 4/metabolism , Insulin Resistance , Lipid Metabolism , Male , Phytotherapy , Polyphenols , RNA, Messenger/metabolism , Random Allocation , Rats , Rats, Wistar
16.
Br J Nutr ; 104(12): 1760-70, 2010 Dec.
Article En | MEDLINE | ID: mdl-20673376

High-fat or high-fat-high-sucrose diets are known to induce non-alcoholic fatty liver disease and this is emerging as one of the most common liver diseases worldwide. Some polyphenols have been reported to decrease rat hepatic lipid accumulation, in particular those extracted from red grapes such as resveratrol. The present study was designed to determine whether a polyphenol extract (PPE), from red grapes, modulates liver fatty acid composition and desaturase activity indexes in rats fed a high-fat-high-sucrose (HFHS) diet, and to explore whether sirtuin-1 deacetylase activation was implicated in the effect of the PPE against liver steatosis. The effect of this PPE on mitochondriogenesis and mitochondrial activity was also explored. The PPE decreased liver TAG content in HFHS+PPE diet-fed rats in comparison with HFHS diet-fed rats. The PPE had no effect on liver fatty acid composition, desaturase activity indexes and stearoyl-CoA desaturase 1 (SCD1) gene expression. Sirtuin-1 deacetylase protein expression was significantly increased with the PPE; AMP kinase protein expression was higher with the PPE in comparison with the HFHS rats, but no modification of phosphorylated AMP kinase was observed. Protein expression of phospho-acetyl-CoA carboxylase was decreased in HFHS rats and returned to basal values with the PPE. Finally, the PPE modulated PPARγ coactivator-1α (PGC-1α) but did not modify mitochondriogenesis and mitochondrial activity. In conclusion, the PPE partially prevented the accumulation of TAG in the liver by regulating acetyl-CoA carboxylase phosphorylation, a key enzyme in lipid metabolism, probably via sirtuin-1 deacetylase activation. However, the PPE had no effect on the qualitative composition of liver fatty acids.


Fatty Acids/metabolism , Flavonoids/pharmacology , Liver/metabolism , Phenols/pharmacology , Plant Extracts/pharmacology , Sirtuin 1/metabolism , Animals , Diet , Dietary Fats/administration & dosage , Dietary Fats/adverse effects , Dietary Sucrose/administration & dosage , Dietary Sucrose/adverse effects , Fatty Liver/chemically induced , Flavonoids/chemistry , Male , Phenols/chemistry , Plant Extracts/chemistry , Polyphenols , RNA, Messenger/genetics , RNA, Messenger/metabolism , Random Allocation , Rats , Rats, Wistar
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