82 results on '"Tag"'
Search Results
2. JcMYB1, a Jatropha R2R3MYB Transcription Factor Gene, Modulates Lipid Biosynthesis in Transgenic Plants.
- Author
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Khan K, Kumar V, Niranjan A, Shanware A, and Sane VA
- Subjects
- Arabidopsis, Fatty Acids biosynthesis, Genes, Plant genetics, Jatropha physiology, Metabolic Networks and Pathways, Plant Proteins physiology, Plants, Genetically Modified, Nicotiana, Transcription Factors physiology, Triglycerides biosynthesis, Two-Hybrid System Techniques, Genes, Plant physiology, Jatropha genetics, Lipids biosynthesis, Plant Proteins genetics, Transcription Factors genetics
- Abstract
The lipid biosynthesis pathway in plants has been studied in detail; however, the factors that regulate the pathway at the transcription level are largely unknown. LEAFY COTYLEDON1 (LEC1), WRINKLED1 (WRI1) and FUSCA3 (FUS3) are considered master regulators to control seed oil content in Arabidopsis. Beside these master regulators, several other transcription factors that may regulate the pathway in plants are poorly studied. In the present work, we have shown the involvement of an uncharacterized Jatropha curcas R2R3MYB gene (JcMYB1) in seed oil biosynthesis. Seed oil analysis and expression profiling of fatty acid (FA) and triacylglycerol (TAG) biosynthetic genes in transgenic Arabidopsis and tobacco plants revealed that JcMYB1 enhances seed oil accumulation and alters FA composition by regulating the expression of endogenous pathway genes in transgenics. Using virus-induced gene silencing (VIGS) in Jatropha, we demonstrated that the suppression of JcMYB1 reduced lipid content with altered FA composition. Agro-infiltration and yeast one-hybrid assay results showed that JcMYB1 protein directly binds to the diacylglycerol acyltransferase1 (DGAT1) promoter, a rate-limiting enzyme of TAG biosynthesis, and activates its expression. These results suggested that JcMYB1 may augment the lipid content by regulating lipid biosynthetic genes. Additionally, manipulation of JcMYB1 in oil crop plants may be used for the potential improvement of oil production and quality., (� The Author(s) 2018. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2019
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3. Lipid-gene regulatory network reveals coregulations of triacylglycerol with phosphatidylinositol/lysophosphatidylinositol and with hexosyl-ceramide.
- Author
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Wang W, Xin J, Yang X, Lam SM, Shui G, Wang Y, and Huang X
- Subjects
- Animals, Cell Line, Ceramides metabolism, Ceramides physiology, Drosophila, Gene Regulatory Networks genetics, HeLa Cells, Homeostasis, Humans, Lipid Metabolism genetics, Lipids physiology, Lysophospholipids metabolism, Signal Transduction, Triglycerides genetics, Lipids genetics, Phosphatidylinositols metabolism, Triglycerides metabolism
- Abstract
Lipid homeostasis is important for executing normal cellular functions and maintaining physiological conditions. The biophysical properties and intricate metabolic network of lipids underlie the coordinated regulation of different lipid species in lipid homeostasis. To reveal the homeostatic response among different lipids, we systematically knocked down 40 lipid metabolism genes in Drosophila S2 cells by RNAi and profiled the lipidomic changes. Clustering analyses of lipids reveal that many pairs of genes acting in a sequential fashion or sharing the same substrate are tightly clustered. Through a lipid-gene regulatory network analysis, we further found that a reduction of triacylglycerol (TAG) is associated with an increase of phosphatidylinositol (PI) and lysophosphatidylinositol (LPI) or a reduction of hexosyl-ceramide (HexCer) and hydroxylated hexosyl-ceramide (OH-HexCer). Importantly, negative coregulation between TAG and LPI/PI, and positive coregulation between TAG and HexCer, were also found in human Hela cells. Together, our results reveal coregulations of TAG with PI/LPI and with HexCer in lipid homeostasis., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2019
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4. Optimizing photon dose and frequency to enhance lipid productivity of thermophilic algae for biofuel production.
- Author
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Abu-Ghosh S, Dubinsky Z, Banet G, and Iluz D
- Subjects
- Biomass, Light, Nitrogen, Photons, Biofuels, Lipids
- Abstract
The aim of this work was to examine the potential of the thermophilic green microalga Micractinium sp. to accumulate triacylglycerols (TAGs) and to develop a light strategy to increase TAG productivity in this alga. To this end, dense cultures of Micractinium sp. were grown at 37 °C under nitrogen (N) starvation and exposed to a light intensity of 1000 µmol photons m
-2 s-1 of different light regimes. The highest per-biomass TAG-content and maximal volumetric productivities of TAG were displayed by the cultures grown under flashing light of 5 Hz with 50% duty cycle. Based on the results, a sufficiently high-starting culture density should be combined with a high irradiance delivered by an appropriate light regime to enhance the production of biomass enriched TAGs., (Copyright © 2018 Elsevier Ltd. All rights reserved.)- Published
- 2018
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5. Reconstruction of the microalga Nannochloropsis salina genome-scale metabolic model with applications to lipid production.
- Author
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Loira N, Mendoza S, Paz Cortés M, Rojas N, Travisany D, Genova AD, Gajardo N, Ehrenfeld N, and Maass A
- Subjects
- Chromosome Mapping, Gene Expression Profiling, Genetic Engineering, Molecular Sequence Annotation, Nitrogen metabolism, Genomics, Lipids biosynthesis, Microalgae genetics, Microalgae metabolism, Models, Biological, Stramenopiles genetics, Stramenopiles metabolism
- Abstract
Background: Nannochloropsis salina (= Eustigmatophyceae) is a marine microalga which has become a biotechnological target because of its high capacity to produce polyunsaturated fatty acids and triacylglycerols. It has been used as a source of biofuel, pigments and food supplements, like Omega 3. Only some Nannochloropsis species have been sequenced, but none of them benefit from a genome-scale metabolic model (GSMM), able to predict its metabolic capabilities., Results: We present iNS934, the first GSMM for N. salina, including 2345 reactions, 934 genes and an exhaustive description of lipid and nitrogen metabolism. iNS934 has a 90% of accuracy when making simple growth/no-growth predictions and has a 15% error rate in predicting growth rates in different experimental conditions. Moreover, iNS934 allowed us to propose 82 different knockout strategies for strain optimization of triacylglycerols., Conclusions: iNS934 provides a powerful tool for metabolic improvement, allowing predictions and simulations of N. salina metabolism under different media and genetic conditions. It also provides a systemic view of N. salina metabolism, potentially guiding research and providing context to -omics data.
- Published
- 2017
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6. Microalgae cultivation as tertiary unit operation for treatment of pharmaceutical wastewater associated with lipid production.
- Author
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Hemalatha M and Venkata Mohan S
- Subjects
- Carbohydrate Metabolism, Drug Industry, Microalgae metabolism, Water Pollutants, Chemical analysis, Water Pollutants, Chemical metabolism, Lipids biosynthesis, Microalgae growth & development, Wastewater analysis, Water Purification
- Abstract
Microalgae based treatment was studied to polish sequential batch reactor (SBR) treated pharmaceutical wastewater under mixotrophic mode of operation with simultaneous biomass/lipid production. At the end of biomass growth phase (BGP), carbon removal efficiency was observed to be 73% along with good removal of nitrates (62%). Since microalgae assimilate nutrients from wastewater for growth, an increment in total biomass productivity (2.8g/l) was observed. Subjecting to nutrient stress phase (NSP), total lipid content of 17.2% with neutral lipids of 6.2% was observed under light condition. Contrarily, dark condition depicted total lipid content of 15.8% with neutral lipids constituting 6.5%. The nutrient stress in combination with light showed marked influence on the profile of saturated and unsaturated fatty acids. Integration of microalgae cultivation improves environmental sustainability and enables greener routes of biofuels and value added products synthesis in a biorefinery approach., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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7. De-novo assembly and characterization of Chlorella minutissima UTEX2341 transcriptome by paired-end sequencing and the identification of genes related to the biosynthesis of lipids for biodiesel.
- Author
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Yu M, Yang S, and Lin X
- Subjects
- Base Sequence, DNA genetics, RNA, Plant genetics, RNA, Plant metabolism, Biofuels, Chlorella genetics, Gene Expression Regulation, Plant physiology, Lipids biosynthesis, Transcriptome
- Abstract
Chlorella minutissima is considered to be one of the promising feedstocks for biofuels in the future. In this study, the transcriptome from the oil-rich strain UTEX2341 of C. minutissima was generated based on Illumina paired-end sequencing. Through de-novo assembly, a total of 14,905 isogenes were obtained and compacted into 6216 unigenes. A total of 80% of the unigenes were assigned with GO terms and were further subdivided into 55 sub-categories. KEGG analysis demonstrated that 37.2% of the unigenes could be accessed and mapped into 278 pathways. Interestingly, the genes that encoded key enzymes that are involved in the biosynthesis, elongation, and metabolism of fatty acids were identified, including malonyl-CoA-ACP transacylase, 3-ketoacyl-ACP synthase, 3-ketoacyl-ACP reductase, and others. Moreover, the genes that are involved in triacylglycerol (TAG) biosynthesis and metabolism were also observed. Therefore, the transcriptome analysis of C. minutissima UTEX2341 not only supplies comprehensive insight into the molecular pathway that is involved in the biosynthesis of biofuel precursors but also provides substantial valuable genomic resources to accelerate the further development and utilization of biofuels., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2016
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8. Molecular analysis of the Mycobacterium tuberculosis lux-like mel2 operon.
- Author
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Janagama HK, Tounkang S, Cirillo SL, Zinniel DK, Barletta RG, and Cirillo JD
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- Cell Proliferation, Chromatography, Thin Layer, Genetic Complementation Test, Humans, Luminescent Proteins metabolism, Macrophages metabolism, Mycobacterium Infections, Nontuberculous genetics, Mycobacterium Infections, Nontuberculous microbiology, Oxidative Stress genetics, Reactive Oxygen Species metabolism, Virulence, Bacterial Proteins metabolism, Cell Wall metabolism, Lipids biosynthesis, Mycobacterium marinum genetics, Mycobacterium tuberculosis genetics, Operon
- Abstract
Using a high throughput genetic strategy, designated Random Inducible Controlled Expression (RICE), we identified the six gene mel2 locus in Mtb and M. marinum. Interestingly, three of the genes present in mel2 have similarities to bioluminescence genes. Similar to other bacterial bioluminescence systems, mel2 facilitates detoxification of reactive oxygen species (ROS). Through the use of thin layer chromatography (TLC) we demonstrate enhanced production of the cell wall virulence lipid, pthiocerol dimycoserosate (PDIM), in a Mtb mel2 mutant relative to the wild type strain in the presence of both H2O2 and diamide oxidative stresses. Furthermore, propionate toxicity assays revealed increased accumulation of triacylglycerol (TAG) in the mel2 mutant relative to wild type. These observations provide the first evidence that mel2 plays a critical role in Mtb lipid biosynthesis., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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9. Combination of lipid metabolism alterations and their sensitivity to inflammatory cytokines in human lipin-1-deficient myoblasts.
- Author
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Michot C, Mamoune A, Vamecq J, Viou MT, Hsieh LS, Testet E, Lainé J, Hubert L, Dessein AF, Fontaine M, Ottolenghi C, Fouillen L, Nadra K, Blanc E, Bastin J, Candon S, Pende M, Munnich A, Smahi A, Djouadi F, Carman GM, Romero N, de Keyzer Y, and de Lonlay P
- Subjects
- Biomarkers metabolism, Blotting, Western, Case-Control Studies, Cell Cycle, Cell Proliferation, Child, Child, Preschool, Endoplasmic Reticulum Stress, Female, Gene Expression Profiling, Humans, Lipid Metabolism Disorders metabolism, Lipid Metabolism Disorders pathology, Male, Muscle Fibers, Skeletal drug effects, Muscle Fibers, Skeletal metabolism, Muscle, Skeletal drug effects, Muscle, Skeletal metabolism, Muscle, Skeletal pathology, Mutation genetics, Myoblasts drug effects, Myoblasts metabolism, Oligonucleotide Array Sequence Analysis, Pancreatitis-Associated Proteins, Phosphatidate Phosphatase metabolism, RNA, Messenger genetics, Real-Time Polymerase Chain Reaction, Reverse Transcriptase Polymerase Chain Reaction, Rhabdomyolysis etiology, Rhabdomyolysis metabolism, Rhabdomyolysis pathology, Cytokines pharmacology, Inflammation Mediators pharmacology, Lipid Metabolism Disorders etiology, Lipids, Muscle Fibers, Skeletal pathology, Myoblasts pathology, Phosphatidate Phosphatase genetics
- Abstract
Lipin-1 deficiency is associated with massive rhabdomyolysis episodes in humans, precipitated by febrile illnesses. Despite well-known roles of lipin-1 in lipid biosynthesis and transcriptional regulation, the pathogenic mechanisms leading to rhabdomyolysis remain unknown. Here we show that primary myoblasts from lipin-1-deficient patients exhibit a dramatic decrease in LPIN1 expression and phosphatidic acid phosphatase 1 activity, and a significant accumulation of lipid droplets (LD). The expression levels of LPIN1-target genes [peroxisome proliferator-activated receptors delta and alpha (PPARδ, PPARα), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), acyl-coenzyme A dehydrogenase, very long (ACADVL), carnitine palmitoyltransferase IB and 2 (CPT1B and CPT2)] were not affected while lipin-2 protein level, a closely related member of the family, was increased. Microarray analysis of patients' myotubes identified 19 down-regulated and 51 up-regulated genes, indicating pleiotropic effects of lipin-1 deficiency. Special attention was paid to the up-regulated ACACB (acetyl-CoA carboxylase beta), a key enzyme in the fatty acid synthesis/oxidation balance. We demonstrated that overexpression of ACACB was associated with free fatty acid accumulation in patients' myoblasts whereas malonyl-carnitine (as a measure of malonyl-CoA) and CPT1 activity were in the normal range in basal conditions accordingly to the normal daily activity reported by the patients. Remarkably ACACB invalidation in patients' myoblasts decreased LD number and size while LPIN1 invalidation in controls induced LD accumulation. Further, pro-inflammatory treatments tumor necrosis factor alpha+Interleukin-1beta(TNF1α+IL-1ß) designed to mimic febrile illness, resulted in increased malonyl-carnitine levels, reduced CPT1 activity and enhanced LD accumulation, a phenomenon reversed by dexamethasone and TNFα or IL-1ß inhibitors. Our data suggest that the pathogenic mechanism of rhabdomyolysis in lipin-1-deficient patients combines the predisposing constitutive impairment of lipid metabolism and its exacerbation by pro-inflammatory cytokines., (© 2013.)
- Published
- 2013
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10. Fat accretion in a subpopulation of hepatocytes as a strategy to protect the whole liver against oxidative stress and lipotoxicity.
- Author
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Fromenty B
- Subjects
- Animals, Hepatocytes cytology, Lipid Metabolism, Lipids chemistry
- Abstract
Fatty liver can be induced by obesity, some drugs and alcohol intoxication. In this liver lesion, lipid accumulation can involve only some hepatocytes but the significance of this cell-to-cell heterogeneity is unknown. In a recent work, Dr Pol et al. propose that high-fat hepatocytes could protect the cell population against oxidative stress and lipotoxicity., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)
- Published
- 2013
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11. Surface analysis of lipids by mass spectrometry: more than just imaging.
- Author
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Ellis SR, Brown SH, In Het Panhuis M, Blanksby SJ, and Mitchell TW
- Subjects
- Humans, Lasers, Lipids isolation & purification, Liquid-Liquid Extraction, Temperature, Lipids analysis, Mass Spectrometry
- Abstract
Mass spectrometry is now an indispensable tool for lipid analysis and is arguably the driving force in the renaissance of lipid research. In its various forms, mass spectrometry is uniquely capable of resolving the extensive compositional and structural diversity of lipids in biological systems. Furthermore, it provides the ability to accurately quantify molecular-level changes in lipid populations associated with changes in metabolism and environment; bringing lipid science to the "omics" age. The recent explosion of mass spectrometry-based surface analysis techniques is fuelling further expansion of the lipidomics field. This is evidenced by the numerous papers published on the subject of mass spectrometric imaging of lipids in recent years. While imaging mass spectrometry provides new and exciting possibilities, it is but one of the many opportunities direct surface analysis offers the lipid researcher. In this review we describe the current state-of-the-art in the direct surface analysis of lipids with a focus on tissue sections, intact cells and thin-layer chromatography substrates. The suitability of these different approaches towards analysis of the major lipid classes along with their current and potential applications in the field of lipid analysis are evaluated., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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12. Lipidomics as a principal tool for advancing biomedical research.
- Author
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Lam SM and Shui G
- Subjects
- Animals, Biomedical Research instrumentation, Humans, Biomedical Research methods, Lipids chemistry
- Abstract
Lipidomics, which targets at the construction of a comprehensive map of lipidome comprising the entire lipid pool within a cell or tissue, is currently emerging as an independent discipline at the interface of lipid biology, technology and medicine. The diversity and complexity of the biological lipidomes call for technical innovation and improvement to meet the needs of various biomedical studies. The recent wave of expansion in the field of lipidomic research is mainly attributed to advances in analytical technologies, in particular, the development of new mass spectrometric and chromatographic tools for the characterization and quantification of the wide array of diverse lipid species in the cellular lipidome. Here, we review some of the key technical advances in lipidome analysis and put forth the applications of lipidomics in addressing the biological roles of lipids in numerous disease models including the metabolic syndrome, neurodegenerative diseases and infectious diseases, as well as the increasing urgency to construct the lipidome inventory for various mammalian/organism models useful for biomedical research., (Copyright © [2103], The Society of Chinese Scholars on Exercise Physiology and Fitness. Published by Elsevier (Singapore) Pvt Ltd. All rights reserved.)
- Published
- 2013
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13. Dietary factors are associated with coronary heart disease risk factors in college students.
- Author
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Fernandes J, Arts J, Dimond E, Hirshberg S, and Lofgren IE
- Subjects
- Adolescent, Alcohol Drinking adverse effects, Blood Glucose metabolism, Cholesterol, HDL blood, Coronary Disease blood, Cross-Sectional Studies, Energy Intake, Exercise, Female, Humans, Logistic Models, Male, Rhode Island, Risk Factors, Students, Triglycerides blood, Universities, Waist Circumference, Body Mass Index, Coronary Disease etiology, Diet, Feeding Behavior, Health Behavior, Lipids blood, Obesity complications
- Abstract
It is hypothesized that healthy dietary and physical activity choices will be inversely associated with coronary heart disease (CHD) risk factors. Results from a cross-sectional study of 294 first-year University of Rhode Island students were used for the analyses. The presence of CHD risk factors was defined by the National Cholesterol Education Program Adult Treatment Panel III guidelines. Diet was assessed by three 24-hour food recalls, and physical activity was assessed by the International Physical Activity Questionnaire. Logistic regression models adjusted for sex estimated the odds of having CHD risk factors. A higher percent of kilocalories from alcohol was associated with a 9.9% increased risk for elevated triacylglycerol (odds ratio [OR], 1.099; 95% confidence interval [CI], 1.000-1.207). Sugar intake (OR, 1.015; 95% CI, 1.004-1.026), saccharin intake (OR, 1.047; 95% CI, 1.015-1.080), and body mass index (BMI; OR, 1.139; 95% CI, 1.037-1.252) were associated with an increased risk of low high-density lipoprotein cholesterol; dietary fiber intake (OR, 0.934; 95% CI, 0.873-1.000) was associated with a decreased risk of low high-density lipoprotein cholesterol. Participants with a higher BMI were 9.4% more likely to have elevated fasting glucose (OR, 1.094; 95% CI, 1.004-1.192) and 193.6% more likely to have a larger waist circumference (OR, 2.936; 95% CI, 1.543-5.586). Dietary factors and BMI are better indicators of CHD risk than physical activity is in this population., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2013
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14. Educational intervention based on the extended parallel process model improves adherence to diabetic diet and glycaemic control indices: a randomised, double-blind, controlled, factorial field trial.
- Author
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Dehghan, Tayebe, Mohsenpour, Mohammad Ali, Karimi, Masoud, Mehrabi, Manoosh, Zare, Morteza, Akbarzadeh, Marzieh, Kohansal, Atefeh, Fathi, Fatemeh, and Sohrabi, Zahra
- Subjects
INTELLECT ,HIGH density lipoproteins ,CONCEPTUAL models ,SELF-efficacy ,GLYCOSYLATED hemoglobin ,EDUCATIONAL outcomes ,LIPIDS ,STATISTICAL sampling ,BLIND experiment ,DESCRIPTIVE statistics ,RANDOMIZED controlled trials ,PSYCHOLOGY ,ATTITUDE (Psychology) ,BLOOD sugar ,WAIST circumference ,LOW density lipoproteins ,TYPE 2 diabetes ,ANTHROPOMETRY ,HEALTH education ,CARBOHYDRATE metabolism ,NUTRITION education ,DIET therapy for diabetes - Abstract
Nutritional education is pivotal in the medical nutritional therapy of type 2 diabetes mellitus (T2DM). The extended parallel process model (EPPM) is a health education method for inducing desirable health behaviours. The present study aimed to investigate the effect of nutritional education based on the EPPM in T2DM patients on knowledge, attitude, practice, anthropometric indices, glycaemic factors, lipid profile and adherence to the diabetic diet. A randomised, double-blind, controlled, factorial field trial was designed for T2DM patients aged 30–59 years (n 88). Participants were randomly allocated into four groups to receive EPPM-based nutritional education through gain framed message (GFM), loss framed message (LFM), their combination (G\LFM) or usual diabetic education in the control group (CG). Participants were assessed before and after the study duration. After 3 months of intervention, eighty participants finished the study. The EPPM-based intervention increased participants' knowledge, behavioural intention, perceived sensitivity, severity, self-efficacy (P < 0·001 for all) and response efficacy (P = 0·029) in comparison with CG. GFM (P = 0·004) and G\FLM (P = 0·034) reduced carbohydrate intake and LFM (P = 0·034) and G\LFM (P = 0·047) decreased fat intake. Between-group analysis indicated interventions reduced weight (P = 0·046), BMI (P = 0·038), fasting blood sugar (P = 0·030), 2-hour postprandial blood glucose (P = 0·027) and TAG (P = 0·002) in comparison with the CG. Results were NS for protein intake, waist and hip circumference, waist:hip ratio, HbA1c, total cholesterol, LDL and HDL. Nutritional education based on EPPM could increase the knowledge and awareness of T2DM patients. Also, it could be beneficial for blood glucose amendment. Further investigations are recommended. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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15. Lipid accumulation mechanism of Amphora coffeaeformis under nitrogen deprivation and its application as a feed additive in Carassius auratus aquaculture.
- Author
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Cui, Yulin, Wang, Kang, Zhou, Xiuzhi, Meng, Chunxiao, and Gao, Zhengquan
- Subjects
- *
GOLDFISH , *UNSATURATED fatty acids , *CRUCIAN carp , *AMPHORAS , *LIPIDS - Abstract
Background: Amphora coffeaeformis, a unicellular diatom, can significantly accumulate lipids under nitrogen (N) limitation. However, the molecular mechanism underlying lipid accumulation in A. coffeaeformis remains unknown and its application development is lagging. Results: This work analyzed the lipid composition of A. coffeaeformis under N deprivation and investigated its mechanism underlying lipid accumulation using RNA-seq. The results showed that the total lipid content of A. coffeaeformis increased from 28.22 to 44.05% after 5 days of N deprivation, while the neutral lipid triacylglycerol (TAG) content increased from 10.41 to 25.21%. The transcriptional profile showed that N deprivation induced wide-ranging reprogramming of regulation and that most physiological activities were repressed, while the upregulation of glycerol-3-phosphate acyltransferase directly determined TAG accumulation. Moreover, we explored the effect of A. coffeaeformis as a food additive on the lipid composition of crucian carp. The results showed that the contents of unsaturated fatty acids in the meat of fish supplemented with A. coffeaeformis were significantly increased, indicating its potential application in animal nutrition for improving meat quality indicators. Conclusion: The findings shed light on the molecular mechanisms of neutral lipid accumulation and revealed the key genes involved in lipid metabolism in A. coffeaeformis. Moreover, we also confirmed that A. coffeaeformis can be used as feed additive for improving the lipid composition of crucian carp meat, which provided evidence for the biotechnology application of this high-oil microalgae. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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16. Structured Lipids Engineering for Health: Novel Formulations Enriched in n -3 Long-Chain Polyunsaturated Fatty Acids with Potential Nutritional Benefits.
- Author
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Lopes, Paula A., Alfaia, Cristina M., Pestana, José M., and Prates, José A. M.
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CHEMICAL processes ,DIETARY fats ,LIPIDS ,FATTY liver ,FATTY acids ,FAT ,UNSATURATED fatty acids - Abstract
Structured lipids (SLs) offer a promising avenue for designing novel formulations enriched in n-3 long-chain polyunsaturated fatty acids (LCPUFAs) with potential health benefits. Triacylglycerols (TAGs), the most common fats in the human diet, are both non-toxic and chemically stable. The metabolic efficiency and digestibility of TAGs are significantly influenced by the position of fatty acids (FAs) within the glycerol backbone, with FAs at the sn-2 position being readily absorbed. Over the past two decades, advancements in SL research have led to the development of modified TAGs, achieved either through chemical or enzymatic processes, resulting in SLs. The ideal structure of SLs involves medium-chain FAs at the sn-1,3 positions and long-chain n-3 LCPUFAs at the sn-2 position of the glycerol backbone, conferring specific physicochemical and nutritional attributes. These tailored SL formulations find wide-ranging applications in the food and nutraceutical industries, showing promise for dietary support in promoting health and mitigating various diseases. In particular, SLs can be harnessed as functional oils to augment TAG metabolism, thereby impeding the development of fatty liver, countering the onset of obesity, and preventing atherosclerosis and age-related chronic diseases. In scrutinising prevailing research trajectories, this review endeavours to provide an in-depth analysis of the multifaceted advantages and repercussions associated with the synthesis of SLs. It elucidates their burgeoning potential in enhancing health and well-being across a range of demographic cohorts. Specifically, the implications of SL utilisation are discussed in the context of healthcare environments and early childhood developmental support. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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17. Study Of Lipids And Lipoprotein Levels In Uncomplicated Diabetes Mellitus Patients Attending Shadan Hospital.
- Author
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Tulla, Samatha, Ahmed Khan, Mohammed Siddique, and Siddiqua, Syeda Ayesha
- Subjects
- *
DYSLIPIDEMIA , *DIABETES , *LDL cholesterol , *PEOPLE with diabetes , *HDL cholesterol , *LIPIDS - Abstract
Background: Lipid and lipoprotein levels are interrelated with diabetes mellitus. Abnormalities in the levels of total cholesterol (TC) or triglycerides (TAG) or low-density lipoprotein (LDL) cholesterol or very-low-density lipoprotein (VLDL) cholesterol or high-density lipoprotein (HDL) cholesterol or lipoprotein (a) [Lp (a)] is traditionally named as dyslipidemia. Diabetes mellitus has been known to be associated with lipid disorders and cardiovascular diseases. In patients with diabetes mellitus, dyslipidemia occurs earlier in life, leading to increased morbidity and mortality rates. The study aims to assess the changes in lipids and lipoprotein levels in uncomplicated diabetes mellitus patients. Methods: A case-control type of study was conducted for 18 months (September 2011 to March 2013) at the Department of General Medicine, Shadan Hospital, Hyderabad. Ethical committee approval was taken before the study from the institutional ethical committee. A total of 120 subjects, 60 non-diabetic (healthy) control subjects with matching age and gender and, 60 cases of subjects with uncomplicated diabetes mellitus were enrolled based on predetermined inclusion and exclusion criteria. Results: This study was conducted to evaluate the changes in lipids and lipoprotein levels between control (normal and healthy subjects) and case (subjects with uncomplicated diabetes mellitus) groups. The Mean±SD levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, and lipoprotein (a) were higher in the cases group and showed statistical significance when compared with the control group. Conclusions: Our study states that there are abnormal levels of lipids and lipoprotein in subjects with uncomplicated diabetes mellitus, which is the foremost cause of cardiovascular diseases, coronary heart disease, dyslipidemia, etc. [ABSTRACT FROM AUTHOR]
- Published
- 2022
18. Functional analysis of alternative castor bean DGAT enzymes
- Author
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Thomaz Stumpf Trenz, Andreia Carina Turchetto-Zolet, Rogério Margis, Marcia Margis-Pinheiro, and Felipe dos Santos Maraschin
- Subjects
TAG ,lipids ,oil ,diacylglycerol acyltransferase ,Ricinus ,Genetics ,QH426-470 - Abstract
Abstract The diversity of diacylglycerol acyltransferases (DGATs) indicates alternative roles for these enzymes in plant metabolism besides triacylglycerol (TAG) biosynthesis. In this work, we functionally characterized castor bean (Ricinus communis L.) DGATs assessing their subcellular localization, expression in seeds, capacity to restore triacylglycerol (TAG) biosynthesis in mutant yeast and evaluating whether they provide tolerance over free fatty acids (FFA) in sensitive yeast. RcDGAT3 displayed a distinct subcellular localization, located in vesicles outside the endoplasmic reticulum (ER) in most leaf epidermal cells. This enzyme was unable to restore TAG biosynthesis in mutant yeast; however, it was able to outperform other DGATs providing higher tolerance over FFA. RcDAcTA subcellular localization was associated with the ER membranes, resembling RcDGAT1 and RcDGAT2, but it failed to rescue the long-chain TAG biosynthesis in mutant yeast, even with fatty acid supplementation. Besides TAG biosynthesis, our results suggest that RcDGAT3 might have alternative functions and roles in lipid metabolism.
- Published
- 2022
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19. Microalgal lipid production: A comparative analysis of <italic>Nannochloropsis</italic> and <italic>Microchloropsis</italic> strains.
- Author
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Abdelkarim, Omnia H., Wijffels, Rene H., and Barbosa, Maria J.
- Subjects
- *
LIGHT intensity , *CONDITIONED response , *LIPIDS , *PHOTONS , *STARVATION - Abstract
The oleaginous genera
Nannochloropsis andMicrochloropsis are recognized for their lipid accumulation capacity. Microalgal lipid accumulation is triggered by nitrogen starvation, negatively affecting photosynthesis and growth. Moreover, light and temperature play pivotal roles in microalgal physiology, lipid accumulation and composition. This study focuses on comparing the responses of eight microalgal strains fromNannochloropsis (N. oceanica Necton, N. oceanica IMET1, Nannochloropsis. sp. CCAP211/78, N. oculata, andN. limnetica) andMicrochloropsis (M. gaditana CCFM01,M. gaditana CCMP526, andM. salina ) to light, temperature, and nitrogen availability. Biomass, lipid content and productivities were monitored under different light intensities (150 (LL) and 600 μmol photons m−2 s−1 (HL)) and temperatures (15, 25, 30℃) under nitrogen (N-) starvation and replete conditions. Under N-starvation and HL,N. sp. exhibited the highest lipid content (59%) and productivity (0.069 g L-1 day-1), whileN. oculata had the lowest lipid content (37.5%) and productivity (0.037 g L-1 day-1) among the eight strains. Notably,M. gaditana CCFM01 achieved the highest EPA content (4.7%), contrasting withN. oceanica IMET1 lowest EPA content (2.9%) under 150 μmol photons m−2 s−1 and N-repletion. The response to temperature fluctuations under LL was strain-dependent.Microchloropsis salina andM. gaditana CCFM01 demonstrated the highest and lowest lipid productivities (0.069 g L-1 day-1 and 0.022 g L-1 day-1, respectively) at 15℃ under N-starvation. Moreover, significant EPA accumulation across various strains was observed inN. oculata (5.7%) under N-repletion at 15°C, surpassingM. gaditana CCFM01 by 40%. Ultimately, the physiological responses to cultivation conditions vary markedly among microalgal strains, even within the same genus or species. This knowledge is essential for selecting suitable strains for the efficient microalgal lipid production industry.Optimi zing cultivation conditions for the maximal lipid production in Nannochloropsis andMicrochloropsisGraphical Abstract: The oleaginous generaNannochloropsis andMicrochloropsis are recognized for their lipid accumulation capacity. Microalgal lipid accumulation is triggered by nitrogen starvation, negatively affecting photosynthesis and growth. Moreover, light and temperature play pivotal roles in microalgal physiology, lipid accumulation and composition. This study focuses on comparing the responses of eight microalgal strains fromNannochloropsis (N. oceanica Necton, N. oceanica IMET1, Nannochloropsis. sp. CCAP211/78, N. oculata, andN. limnetica) andMicrochloropsis (M. gaditana CCFM01,M. gaditana CCMP526, andM. salina ) to light, temperature, and nitrogen availability. Biomass, lipid content and productivities were monitored under different light intensities (150 (LL) and 600 μmol photons m−2 s−1 (HL)) and temperatures (15, 25, 30℃) under nitrogen (N-) starvation and replete conditions. Under N-starvation and HL,N. sp. exhibited the highest lipid content (59%) and productivity (0.069 g L-1 day-1), whileN. oculata had the lowest lipid content (37.5%) and productivity (0.037 g L-1 day-1) among the eight strains. Notably,M. gaditana CCFM01 achieved the highest EPA content (4.7%), contrasting withN. oceanica IMET1 lowest EPA content (2.9%) under 150 μmol photons m−2 s−1 and N-repletion. The response to temperature fluctuations under LL was strain-dependent.Microchloropsis salina andM. gaditana CCFM01 demonstrated the highest and lowest lipid productivities (0.069 g L-1 day-1 and 0.022 g L-1 day-1, respectively) at 15℃ under N-starvation. Moreover, significant EPA accumulation across various strains was observed inN. oculata (5.7%) under N-repletion at 15°C, surpassingM. gaditana CCFM01 by 40%. Ultimately, the physiological responses to cultivation conditions vary markedly among microalgal strains, even within the same genus or species. This knowledge is essential for selecting suitable strains for the efficient microalgal lipid production industry.Optimi zing cultivation conditions for the maximal lipid production in Nannochloropsis andMicrochloropsis [ABSTRACT FROM AUTHOR]- Published
- 2024
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20. The effect of honey on lipid profiles: a systematic review and meta-analysis of controlled clinical trials.
- Author
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Gholami, Zohreh, Sohrabi, Zahra, Zare, Morteza, Pourrajab, Behnaz, and Nasimi, Nasrin
- Subjects
HONEY analysis ,ONLINE information services ,MEDICAL databases ,HDL cholesterol ,META-analysis ,MEDICAL information storage & retrieval systems ,CLINICAL trials ,CONFIDENCE intervals ,SYSTEMATIC reviews ,LDL cholesterol ,HYPERLIPIDEMIA ,QUALITY assurance ,DESCRIPTIVE statistics ,MEDLINE ,DATA analysis software ,LIPIDS ,CHOLESTEROL - Abstract
The article discusses the effect of honey on lipid profiles.
- Published
- 2022
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21. Enhanced microalgae biomass and lipid output for increased biodiesel productivity.
- Author
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Morais, Keli C.C., Conceição, Daniele, Vargas, José V.C., Mitchell, David A., Mariano, André B., Ordonez, Juan C., Galli-Terasawa, Lygia Vitoria, and Kava, Vanessa M.
- Subjects
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GLUCOSE analysis , *BIOMASS , *LIPIDS , *PHAEODACTYLUM tricornutum , *MICROALGAE , *GLYCERIN , *FATTY acid methyl esters - Abstract
This paper investigated the cumulative impact of salinity, carbon source (glycerol and glucose) and photoperiod on the cultivation of the microalga Phaeodactylum tricornutum in mixotrophic growth in pure air supplied photobioreactors aiming at biomass output and lipid content enhancement for increased biodiesel productivity. For that, Phaeodactylum tricornutum was grown for 18 and 20 days in modified F2 medium which was supplied in the beginning of the culture, and with daily addition of glycerol (0.1 M) or glucose (0.05 M); salinity at 15 and 30‰, with the luminosity of 165 μmols photons m−2s−2 for 24 h day−1 or partial 12 h day−1. Biomass production was registered, total lipids quantified with the Bligh and Dyer methodology, and the lipids' drops observed with Nile Red staining. Regarding salinity, a value of 15‰ led to the highest microalgae growth. Glycerol 0.1 M was the carbon source which provided the best assimilation by the microalgae, reaching up to 1.3 g L−1 of biomass. The 24 h-illumination photoperiod with glycerol in mixotrophic cultivation led to 338.97 mg L−1 of lipids, which was roughly 80% higher than the lipid content obtained with autotrophic growth. In conclusion, the most effective conditions were glycerol 0.1 M (carbon source), 15‰ salinity, and 24 h-illumination. Image 1 • Salinity, carbon source and photoperiod effect on microalgae growth. • No CO 2 injection on microalgae mixotrophic cultivation outcome. • Lipids identification with Nile Red staining. • Glycerol and glucose comparative analysis on lipid production. • Glycerol addition produced 80% more lipid content than autotrophic growth. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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22. Supplementation with EPA or fish oil for 11 months lowers circulating lipids, but does not delay the onset of diabetes in UC Davis-type 2 diabetes mellitus rats
- Author
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Cummings, Bethany P, Stanhope, Kimber L, Graham, James L, Griffen, Steven C, and Havel, Peter J
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Agricultural ,Veterinary and Food Sciences ,Biomedical and Clinical Sciences ,Nutrition and Dietetics ,Nutrition ,Prevention ,Obesity ,Diabetes ,Complementary and Integrative Health ,Metabolic and endocrine ,Age of Onset ,Animals ,Cholesterol ,Diabetes Mellitus ,Type 2 ,Dietary Fats ,Dietary Supplements ,Eicosapentaenoic Acid ,Fatty Acids ,Nonesterified ,Fish Oils ,Hypolipidemic Agents ,Lipids ,Male ,Rats ,Rats ,Inbred Strains ,Triglycerides ,Diabetes prevention ,EPA ,Fish oil ,TAG ,Animal Production ,Food Sciences ,Nutrition & Dietetics ,Animal production ,Food sciences ,Nutrition and dietetics - Abstract
EPA or fish oil supplementation has been suggested as treatments for the prevention of type 2 diabetes mellitus (T2DM) due to their lipid-lowering and potential insulin-sensitising effects. We investigated the effects of supplementation with EPA (1 g/kg body weight per d) or fish oil (3 g/kg body weight per d) on the age of onset of T2DM and circulating glucose, insulin, lipids, leptin and adiponectin in UC Davis (UCD)-T2DM rats. Animals were divided into three groups starting at 1 month of age: control, EPA and fish oil. All the animals were followed until diabetes onset or for up to 12 months of age. Monthly fasting blood samples were collected for the measurement of glucose, lipids, hormones and C-reactive protein (CRP). Neither EPA nor fish oil delayed the onset of T2DM or altered fasting plasma glucose, insulin, CRP, adiponectin or leptin concentrations. The groups did not differ in energy intake or body weight. Fish oil treatment lowered fasting plasma TAG concentrations by 39 (sd 7) % (P < 0.001) and EPA lowered fasting plasma NEFA concentrations by 23 (sd 5) % (P < 0.05) at 4 months of age compared with the control group. EPA and fish oil lowered fasting plasma cholesterol concentrations at 4 months of age by 19 (sd 4) and 22 (sd 4) % compared with the control group, respectively (both P < 0.01). In conclusion, EPA and fish oil supplementation lowers circulating lipid concentrations, but does not delay the onset of T2DM in UCD-T2DM rats.
- Published
- 2010
23. Temperature-Dependent Lipid Accumulation in the Polar Marine Microalga Chlamydomonas malina RCC2488.
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Morales-Sánchez, Daniela, Schulze, Peter S. C., Kiron, Viswanath, and Wijffels, Rene H.
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CHLAMYDOMONAS ,NITROGEN deficiency ,LIPIDS ,UNSATURATED fatty acids ,LIPID synthesis - Abstract
The exploration of cold-adapted microalgae offers a wide range of biotechnological applications that can be used for human, animal, and environmental benefits in colder climates. Previously, when the polar marine microalga Chlamydomonas malina RCC2488 was cultivated under both nitrogen replete and depleted conditions at 8°C, it accumulated lipids and carbohydrates (up to 32 and 49%, respectively), while protein synthesis decreased (up to 15%). We hypothesized that the cultivation temperature had a more significant impact on lipid accumulation than the nitrogen availability in C. malina. Lipid accumulation was tested at three different temperatures, 4, 8, and 15°C, under nitrogen replete and depleted conditions. At 4°C under the nitrogen replete condition C. malina had the maximal biomass productivity (701.6 mg L
–1 day–1 ). At this condition, protein content was higher than lipids and carbohydrates. The lipid fraction was mainly composed of polyunsaturated fatty acids (PUFA) in the polar lipid portion, achieving the highest PUFA productivity (122.5 mg L–1 day–1 ). At this temperature, under nitrogen deficiency, the accumulation of carbohydrates and neutral lipids was stimulated. At 8 and 15°C, under both nitrogen replete and depleted conditions, the lipid and carbohydrate content were higher than at 4°C, and the nitrogen stress condition did not affect the algal biochemical composition. These results suggest that C. malina is a polar marine microalga with a favorable growth temperature at 4°C and is stressed at temperatures ≥8°C, which directs the metabolism to the synthesis of lipids and carbohydrates. Nevertheless, C. malina RCC2488 is a microalga suitable for PUFA production at low temperatures with biomass productivities comparable with mesophilic strains. [ABSTRACT FROM AUTHOR]- Published
- 2020
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24. Impairment of MET transcriptional activators, MET4 and MET31 induced lipid accumulation in Saccharomyces cerevisiae.
- Author
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Rajakumar, Selvaraj, Suriyagandhi, Vennila, and Nachiappan, Vasanthi
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SACCHAROMYCES cerevisiae , *LIPIDS , *METABOLIC models , *LIPID synthesis , *DISABILITIES , *LIPID metabolism - Abstract
The genes involved in the methionine pathway are closely associated with phospholipid homeostasis in yeast. The impact of the deletion of methionine (MET) transcriptional activators (MET31 , MET32 and MET4) in lipid homeostasis is studied. Our lipid profiling data showed that aberrant phospholipid and neutral lipid accumulation occurred in met31∆ and met4∆ strains with low Met. The expression pattern of phospholipid biosynthetic genes such as CHO2, OPI3 and triacylglycerol (TAG) biosynthetic gene, DGA1 were upregulated in met31∆ , and met4∆ strains when compared to wild type (WT). The accumulation of triacylglycerol and sterol esters (SE) content supports the concomitant increase in lipid droplets in met31∆ and met4∆ strains. However, excessive supplies of methionine (1 mM) in the cells lacking the MET transcriptional activators MET31 and MET4 ameliorates the abnormal lipogenesis and causes aberrant lipid accumulation. These findings implicate the methionine accessibility plays a pivotal role in lipid metabolism in the yeast model. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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25. Development of a fatty liver model using oleic acid in primary liver cells isolated from Atlantic salmon and the prevention of lipid accumulation using metformin.
- Author
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Espe, Marit, Xie, Shiwei, Chen, Shijun, Pedro, Araujo, and Holen, Elisabeth
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- *
FATTY liver , *ATLANTIC salmon , *OLEIC acid , *PRIMARY cell culture , *LIVER cells , *LIPIDS - Abstract
The following study aimed to develop a fatty liver model in primary hepatocytes isolated from Atlantic salmon. In order to induce the fatty liver, oleic acid (OA) at 0.2 or 0.4 mM was used. Metformin, known to prevent and cure fatty liver in mammalian cells, was used at 1 or 10 mM for 24 hr before addition of OA to test possible prevention effect of metformin on the OA‐induced fatty liver phenotype. Cells grown in 0.2 mM OA did not increase the mean number of lipid droplets, while cells grown in 0.4 mM OA increased the number of lipid droplets within the liver cells (p < 0.0001). Metformin pretreatment prior to OA supplementation reduced the mean number of lipid droplets. Gene expression of ApoB100, CD36 and PPARa increased in cells treated with metformin and most so at 10 mM. On the other hand, gene expression of LXR, SREBP2 and CPT‐1 decreased at both concentrations of metformin, while OA treatment did not affect these genes. Gene expression of IL‐8 increased by 0.4 mM OA (p = 0.002). Metformin reduced the gene expression of IL‐8. Thus, metformin efficiently enhanced the expression of genes related to transport and oxidation of lipids in hepatic cells of salmon, but required higher concentrations of OA and metformin than those required in rodent models to increase and prevent lipid accumulation, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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26. Concept of lipid droplet biogenesis.
- Author
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Kumari, R.Mankamna, Khatri, Amit, Chaudhary, Ritika, and Choudhary, Vineet
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- *
LIPIDS , *LIPIDOSES , *LIPID synthesis , *DISCONTINUOUS precipitation , *CELL physiology , *FAT - Abstract
Lipid droplets (LD) are functionally conserved fat storage organelles found in all cell types. LDs have a unique structure comprising of a hydrophobic core of neutral lipids (fat), triacylglycerol (TAG) and cholesterol esters (CE) surrounded by a phospholipid monolayer. LD surface is decorated by a multitude of proteins and enzymes rendering this compartment functional. Accumulating evidence suggests that LDs originate from discrete ER-subdomains, demarcated by the lipodystrophy protein seipin, however, the mechanisms of which are not well understood. LD biogenesis factors together with biophysical properties of the ER membrane orchestrate spatiotemporal regulation of LD nucleation and growth at specific ER subdomains in response to metabolic cues. Defects in LD formation manifests in several human pathologies, including obesity, lipodystrophy, ectopic fat accumulation, and insulin resistance. Here, we review recent advances in understanding the molecular events during initial stages of eukaryotic LD assembly and discuss the critical role of factors that ensure fidelity of this process. • Lipid droplets store excess fat and play crucial role in cell physiology. • Assembly of LDs occurs at specialized ER subdomains marked by the seipin-complex. • Number of LD biogenesis sites is regulated in a dynamic manner in response to metabolic cues that drives neutral lipid synthesis. • LD assembly factors, locally enriched lipids, membrane geometry, and biophysical properties of the ER influence LD nucleation. • Seipin has emerged as a general LD assembly factor responsible for nucleation of different classes of neutral lipids. • Characterization of LD associated factors holds the key to mechanistic understanding of LD biogenesis. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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27. Functional analysis of alternative castor bean DGAT enzymes
- Author
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Thomaz Stumpf Trenz, Andreia Carina Turchetto-Zolet, Rogério Margis, Marcia Margis-Pinheiro, and Felipe dos Santos Maraschin
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lipids ,Ricinus ,TAG ,Genetics ,diacylglycerol acyltransferase ,oil ,Molecular Biology - Abstract
The diversity of diacylglycerol acyltransferases (DGATs) indicates alternative roles for these enzymes in plant metabolism besides triacylglycerol (TAG) biosynthesis. In this work, we functionally characterized castor bean (Ricinus communis L.) DGATs assessing their subcellular localization, expression in seeds, capacity to restore triacylglycerol (TAG) biosynthesis in mutant yeast and evaluating whether they provide tolerance over free fatty acids (FFA) in sensitive yeast. RcDGAT3 displayed a distinct subcellular localization, located in vesicles outside the endoplasmic reticulum (ER) in most leaf epidermal cells. This enzyme was unable to restore TAG biosynthesis in mutant yeast; however, it was able to outperform other DGATs providing higher tolerance over FFA. RcDAcTA subcellular localization was associated with the ER membranes, resembling RcDGAT1 and RcDGAT2, but it failed to rescue the long-chain TAG biosynthesis in mutant yeast, even with fatty acid supplementation. Besides TAG biosynthesis, our results suggest that RcDGAT3 might have alternative functions and roles in lipid metabolism.
- Published
- 2023
28. Brown adipose tissue and lipid metabolism: New strategies for identification of activators and biomarkers with clinical potential.
- Author
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Xiang, Angie S., Meikle, Peter J., Carey, Andrew L., and Kingwell, Bronwyn A.
- Subjects
- *
BROWN adipose tissue , *OBESITY , *COMORBIDITY , *LIPID metabolism , *LIPIDS - Abstract
Abstract Development of therapeutic agents directed towards increasing brown adipose tissue (BAT) energy expenditure to combat obesity and its comorbidities is currently an area of intense research. Both preclinical and clinical studies have suggested a potentially significant role for BAT in regulating whole body energy expenditure as well as glucose and lipid metabolism. Lipids, particularly long chain fatty acids (LCFAs), are recognized as integral substrates in mediating the primary heat-producing functions of BAT, and to date thought to be principally sourced from stored intracellular lipid droplets. While this prior understanding is not disputed, recent evidence has demonstrated the importance of lipids derived from the circulation, including those from dietary sources and from tissue lipolysis, especially white adipose tissue lipolysis. Moreover, recent studies have shed further light on a potential role for BAT as an autocrine, paracrine and endocrine organ, with lipids as key signaling molecules. Advances in metabolomics have enabled high-resolution exploration of biomolecules that may be associated with various physiological processes and potentially pathological states. Such approaches have led to several novel lipid species recently being associated with BAT function and dysfunction. Further exploration of the circulating lipidome will likely reveal additional novel BAT biomarkers that can inform development of BAT-directed therapies. This review will address current progress and new strategies to identify and characterize BAT-associated lipids which may represent both novel activators and/or activity biomarkers with both research and clinical utility. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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29. Improving the chemical properties of Buriti oil (Mauritia flexuosa L.) by enzymatic interesterification.
- Author
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Speranza, P., Leãoa, K. M. M., Narciso Gomes, T. S., Reisa, L. V. C., Rodrigues, A. P., Macedo, J. Alves, Ribeiro, A. P. B., and Macedo, G. Alves
- Subjects
- *
MAURITIA flexuosa , *EDIBLE fats & oils , *ESTERIFICATION , *LIPIDS , *BETA carotene , *VEGETABLE oils , *VITAMIN E - Abstract
Although Amazonian oils present great potential for various applications, they have not been extensively explored for commercial use. In this study, the effects of enzymatic interesterification of buriti oil in relation to its triacylglycerol composition, regiospecific distribution of fatty acids, and minority compounds were evaluated. The results indicated that the lipase used in the reaction showed higher specificity for oleic acid and the sn-1 and sn-3 positions of triacylglycerol, generating more unsaturated structured lipids. There were increases of 11% and 12.5% in unsaturated-unsaturated-unsaturated triacylglycerol types and reductions of 12.1% and 16.2% in saturated-unsaturated-unsaturated triacylglycerol types after 6 and 24 hours of reaction, respectively. At 24 h of reaction, the structured lipid formed was totally unsaturated at the three triacylglycerol positions. In addition, as the reaction conditions were mild, the carotenoids and phenolic compounds were maintained in the structured lipids. The results indicate that the enzymatic interesterification can be an alternative to produce structured lipids with new functionalities, and diversify the application of this oil from the Amazon. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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30. Lipid metabolism alterations in the neuronal response to A53T α-synuclein and Fe-induced injury.
- Author
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Sánchez Campos, Sofía, Alza, Natalia P., and Salvador, Gabriela A.
- Subjects
- *
TRIGLYCERIDES , *LIPIDS , *PARKINSON'S disease , *OXIDATIVE stress , *NEURONS - Abstract
Abstract Pathological α-synuclein (α-syn) overexpression and iron (Fe)-induced oxidative stress (OS) are involved in the death of dopaminergic neurons in Parkinson's disease (PD). We have previously characterized the role of triacylglycerol (TAG) formation in the neuronal response to Fe-induced OS. In this work we characterize the role of the α-syn variant A53T during Fe-induced injury and investigate whether lipid metabolism has implications for neuronal fate. To this end, we used the N27 dopaminergic neuronal cell line either untransfected (UT) or stably transfected with pcDNA3 vector (as a transfection control) or pcDNA-A53T-α-syn (A53T α-syn). The overexpression of A53T α-syn triggered an increase in TAG content mainly due to the activation of Acyl-CoA synthetase. Since fatty acid (FA) β-oxidation and phospholipid content did not change in A53T α-syn cells, the unique consequence of the increase in FA-CoA derivatives was their acylation in TAG moieties. Control cells exposed to Fe-induced injury displayed increased OS markers and TAG content. Intriguingly, Fe exposure in A53T α-syn cells promoted a decrease in OS markers accompanied by α-syn aggregation and elevated TAG content. We report here new evidence of a differential role played by A53T α-syn in neuronal lipid metabolism as related to the neuronal response to OS. Graphical abstract Effect of A53T α-syn overexpression and Fe exposure on neuronal lipid metabolism. A53T α-syn overexpression increased FAS expression levels, ACS activity and TAG content. A53T α-syn diminished ROS generation and lipid peroxidation induced by Fe-exposure. A53T α-syn cells exposed to Fe showed increased TAG content. The appearance of TAG in A53T α-syn cells could constitute a marker of neuronal injury during the early stages of PD. Image 1 Highlights • A53T α-syn overexpression induced TAG and lipid droplet accumulation in dopaminergic neurons. • Dopaminergic neurons that overexpressed A53T α-syn displayed augmented Acyl-CoA synthetase activity. • Fe induced A53T α-syn aggregation and increased TAG content in neurons. • Blockage of TAG synthesis reduced A53T α-syn cell viability. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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31. Intermittent <italic>v</italic>. continuous energy restriction: differential effects on postprandial glucose and lipid metabolism following matched weight loss in overweight/obese participants.
- Author
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Antoni, Rona, Johnston, Kelly L., Collins, Adam L., and Robertson, M. Denise
- Subjects
LIPID metabolism ,REDUCING diets ,BLOOD sugar ,HEALTH promotion ,INGESTION ,PROBABILITY theory ,WEIGHT loss ,DATA analysis software ,DESCRIPTIVE statistics - Abstract
The intermittent energy restriction (IER) approach to weight loss involves short periods of substantial (>70 %) energy restriction (ER) interspersed with normal eating. Studies to date comparing IER to continuous energy restriction (CER) have predominantly measured fasting indices of cardiometabolic risk. This study aimed to compare the effects of IER and CER on postprandial glucose and lipid metabolism following matched weight loss. In all, twenty-seven (thirteen male) overweight/obese participants (46 (sem 3) years, 30·1 (sem 1·0) kg/m
2 ) who were randomised to either an IER intervention (2638 kJ for 2 d/week with an overall ER of 22 (sem 0·3) %,n 15) or a CER intervention (2510 kJ below requirements with overall ER of 23 (sem 0·8) %) completed the study. Postprandial responses to a test meal (over 360 min) and changes in anthropometry (fat mass, fat-free mass, circumferences) were assessed at baseline and upon attainment of 5 % weight loss, following a 7-d period of weight stabilisation. The study found no statistically significant difference in the time to attain a 5 % weight loss between groups (median 59 d (interquartile range (IQR) 41–80) and 73 d (IQR 48–128), respectively,P =0·246), or in body composition (P ≥ 0·437). For postprandial measures, neither diet significantly altered glycaemia (P =0·266), whereas insulinaemia was reduced comparatively (P =0·903). The reduction in C-peptide tended (P =0·057) to be greater following IER (309 128 (sem23 268) to 247781 (sem20 709) pmol×360 min/l)v . CER (297 204 (sem25 112) to 301 655 (sem32 714) pmol×360 min/l). The relative reduction in TAG responses was greater (P =0·045) following IER (106 (sem30) to 68 (sem 15) mmol×360 min/l) compared with CER (117 (sem 43) to 130 (sem 31) mmol×360 min/l). In conclusion, these preliminary findings highlight underlying differences between IER and CER, including a superiority of IER in reducing postprandial lipaemia, which now warrant targeted mechanistic evaluation within larger study cohorts. [ABSTRACT FROM AUTHOR]- Published
- 2018
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32. Triacylglycerol: nourishing molecule in endurance of Mycobacterium tuberculosis.
- Author
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MALI, PRATAP C. and MEENA, LAXMAN S.
- Subjects
- *
MYCOBACTERIUM tuberculosis , *LIPIDS , *TRIGLYCERIDES , *ALVEOLAR macrophages , *TUBERCULOSIS prevention - Abstract
The ability of Mycobacterium tuberculosis (M. tuberculosis) to accumulate lipid-rich molecules as an energy source obtained from host cell debris remains interesting. Additionally, the potential of M. tuberculosis to survive under different stress conditions leading to its dormant state in pathogenesis remains elusive. The exact mechanism by which these lipid bodies generated in M. tuberculosis infection and utilized by bacilli inside infected macrophage for its survival is still not understood. In this, during bacillary infection, many metabolic pathways are involved that influence the survival of M. tuberculosis for their own support. However, the exact energy source derived from infecting host cells remain elusive. Therefore, this study highlights several alternative energy sources in the form of triacylglycerol (TAG) and fatty acids, i.e. oleic acids accumulation, which are essential in dormancy-like state under M. tuberculosis infection. The prominent stage in tuberculosis (TB) infection is re-establishment of M. tuberculosis under stress conditions and deployment of a confined strategy to utilize these biomolecules for its persistence survival. So, growing in our understanding of these pathways will help us in accelerating therapies, which could reduce TB prevalence world widely. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
33. The influence of dietary and supplemental calcium on postprandial effects of a high-fat meal on lipaemia, glycaemia, C-reactive protein and adiponectin in obese women.
- Author
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Ferreira, Thaís Da S., Antunes, Vanessa P., Leal, Priscila M., Sanjuliani, Antonio F., and Klein, Márcia R. S. T.
- Subjects
BIOMARKERS ,BLOOD testing ,C-reactive protein ,DIETARY calcium ,COMPARATIVE studies ,CROSSOVER trials ,FAT content of food ,GLUCOSE ,INGESTION ,LIPIDS ,OBESITY ,STATISTICAL sampling ,WOMEN'S health ,CALCIUM compounds ,RANDOMIZED controlled trials ,ADIPONECTIN ,PHARMACODYNAMICS - Abstract
Non-fasting hypertriacylglycerolaemia is a risk factor for CVD and the amount of fat in a meal seems to be the main factor influencing postprandial lipaemia. Although several studies suggest that Ca can increase faecal fat excretion, it is not known whether Ca can decrease postprandial TAG. This study aimed to evaluate the influence of dietary Ca (DC) and supplemental Ca (SC) on lipaemia, glucose metabolism, C-reactive protein (CRP) and adiponectin during postprandial period in obese women challenged with a high-fat meal. In this cross-over controlled trial, sixteen obese women aged 20–50 years were randomly assigned to receive three test meals (approximately 2900 kJ; 48 % fat): high DC (547 mg DC), high SC (HSCM; 500 mg SC-calcium carbonate) and low Ca (42 mg DC). Blood samples were collected in the fasting period and at minutes 120 and 240 after meals to evaluate total cholesterol and fractions, TAG, glucose, insulin, high-sensitivity CRP and adiponectin. Serum levels of TAG and insulin increased significantly after all test meals. Only after HSCM total cholesterol did not present a significant increase and LDL-cholesterol had a significant decrease. Postprandial glucose, HDL-cholesterol, CRP and adiponectin did not present significant changes after the three test meals. The comparative analysis of the effects of the three test meals on serum lipids, glucose, insulin, CRP and adiponectin revealed no significant meal-by-time interaction. These results suggest that in obese women challenged with a high-fat meal DC and SC do not interfere with postprandial lipaemia, glucose metabolism, CRP and adiponectin. [ABSTRACT FROM PUBLISHER]
- Published
- 2017
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- View/download PDF
34. The expanding role of sphingolipids in lipid droplet biogenesis.
- Author
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Deevska, Gergana M. and Nikolova-Karakashian, Mariana N.
- Subjects
- *
LIPIDS , *ORIGIN of life , *SPHINGOLIPIDS , *BIOACTIVE compounds , *GLYCEROPHOSPHOLIPIDS - Abstract
Sphingolipids are a diverse class of lipids that have regulatory, structural, and metabolic functions. Although chemically distinct from the neutral lipids and the glycerophospholipids, which are the main lipid components of the lipid droplets, sphingolipids have nonetheless been shown to influence lipid droplet formation. The goal of this article is to review the available information and provide a cohesive picture of the role sphingolipids play in lipid droplet biogenesis. The following topics are discussed: (i) the abundance of sphingolipids in lipid droplets and their functional significance; (ii) cross-talk between the synthetic pathways of sphingolipids, glycerophospholipids, and neutral lipids; (iii) the impact of bioactive sphingolipids on TAG synthesis and degradation; (iv) interactions between sphingolipids and other lipid droplet components, like cholesterol esters and proteins; (v) inhibition/genetic deletion of specific sphingolipid metabolic enzymes and the resulting effects on lipid droplet formation in mouse models. This article is part of a Special Issue entitled: Recent Advances in Lipid Droplet Biology edited by Rosalind Coleman and Matthijs Hesselink. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
35. Selection of oleaginous yeasts for fatty acid production.
- Author
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Lamers, Dennis, van Biezen, Nick, Martens, Dirk, Peters, Linda, van de Zilver, Eric, Dreumel, Nicole Jacobs-van, Wijffels, René H., and Lokman, Christien
- Subjects
- *
YEAST , *FATTY acid synthesis , *LIPIDS , *BIOMASS energy , *SCHWANNIOMYCES occidentalis - Abstract
Background: Oleaginous yeast species are an alternative for the production of lipids or triacylglycerides (TAGs). These yeasts are usually non-pathogenic and able to store TAGs ranging from 20% to 70% of their cell mass depending on culture conditions. TAGs originating from oleaginous yeasts can be used as the so-called second generation biofuels, which are based on non-food competing "waste carbon sources". Results: In this study the selection of potentially new interesting oleaginous yeast strains is described. Important selection criteria were: a broad maximum temperature and pH range for growth (robustness of the strain), a broad spectrum of carbon sources that can be metabolized (preferably including C-5 sugars), a high total fatty acid content in combination with a low glycogen content and genetic accessibility. Conclusions: Based on these selection criteria, among 24 screened species, Schwanniomyces occidentalis (Debaromyces occidentalis) CBS2864 was selected as a promising strain for the production of high amounts of lipids. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
36. Effects of Soy Protein Containing of Isoflavones and Isoflavones Extract on Plasma Lipid Profile in Postmenopausal Women as a Potential Prevention Factor in Cardiovascular Diseases: Systematic Review and Meta-Analysis of Randomized Controlled Trials
- Author
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Agata Błaszczuk, Wiesław Kanadys, Agnieszka Barańska, Marian Jędrych, Bożena Baczewska, Małgorzata Polz-Dacewicz, and Ewelina Wawryk-Gawda
- Subjects
postmenopausal women ,030204 cardiovascular system & hematology ,Cochrane Library ,law.invention ,chemistry.chemical_compound ,0302 clinical medicine ,Randomized controlled trial ,soy isoflavones extracts ,law ,Casein ,Medicine ,TX341-641 ,Soy protein ,Randomized Controlled Trials as Topic ,Nutrition and Dietetics ,medicine.diagnostic_test ,Isoflavones ,Middle Aged ,Lipids ,Postmenopause ,lipid profile ,Soybean Proteins ,Female ,TC ,medicine.medical_specialty ,030209 endocrinology & metabolism ,Placebo ,Article ,03 medical and health sciences ,Internal medicine ,Humans ,HDL-C ,LDL-C ,Triglycerides ,business.industry ,Nutrition. Foods and food supply ,Plant Extracts ,Cholesterol, HDL ,Lipid metabolism ,Cholesterol, LDL ,Lipid Metabolism ,cardiovascular diseases ,Endocrinology ,chemistry ,TAG ,soy protein containing isoflavones ,business ,Lipid profile ,Food Science - Abstract
The aim of the report was to evaluate the impact of soy protein containing isoflavones and soy isoflavones extract on lipid profile in postmenopausal women, as compared with placebo or protein of milk, casein or isolated soy protein with or without trace isoflavone content. We used the following databases: MEDLINE (PubMed), EMBASE and the Cochrane Library. Quantitative data synthesis was performed by applying a random-effects model. Subgroup analysis and meta-regression were performed to assess the modifiers of treatment response. In total, in the analysis studies, 2305 postmenopausal women took part. Changes in the lipid profile showed statistically significant decreases of total cholesterol by −0.12 (95% CI: −0.21, −0.03) mmol/L, −4.64 (95% CI: −8.12, −1.16) mg/dL, p = 0.01 and increased HDL-cholesterol by 0.03 (95% CI: 0.00, 0.06) mmol/L, 1.15 (95% CI: 0.00, 1.93) mg/dL, p = 0.05, as well as in LDL-cholesterol −0.05 (95% CI: −0.11, 0.01) mmol/L, −1.93 (95% CI: −4.25, 0.39) mg/dL, p = 0.08 and triacylglycerols −0.07 (95% CI: −0.14, 0.00) mmol/L, −6.123 (95% CI: −12.25, 0.00) mg/dL, p = 0.06. Our results suggests that soy and its isoflavones can be effective in correction changes in lipid metabolism in postmenopausal women and may favorably influence in preventing cardiovascular events.
- Published
- 2021
- Full Text
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37. The association between serum lipids and colorectal neoplasm: a systemic review and meta-analysis.
- Author
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Yun Tian, Keming Wang, Juan Li, Jirong Wang, Zhaoxia Wang, Yingrui Fan, Ying Ye, Guozhong Ji, Yi Li, Tian, Yun, Wang, Keming, Li, Juan, Wang, Jirong, Wang, Zhaoxia, Fan, Yingrui, Ye, Ying, Ji, Guozhong, and Li, Yi
- Subjects
- *
BLOOD serum analysis , *COLON cancer , *META-analysis , *LIPIDS , *CHOLESTEROL - Abstract
Objective: There have been inconsistent results published regarding the relationship between dyslipidaemia and an increased risk of colorectal neoplasia (CRN), including colorectal adenoma (CRA) and colorectal cancer (CRC). We conducted a meta-analysis to explore the relationship between dyslipidaemia and CRN.Design: We identified studies by performing a literature search using PubMed, EMBASE and the Science Citation Index through October 2013.Setting: We analysed thirty-three independent studies reporting the association between CRN and at least one of the selected lipid components, including total cholesterol (TC), TAG, HDL-cholesterol (HDL-C) and LDL-cholesterol (LDL-C).Subjects: CRN cases (n 21 809) were identified.Results: Overall, people with high levels of serum TAG (risk ratio (RR)=1.08; 95% CI 1.05, 1.12, P<0.00001) and LDL-C (RR=1.07; 95% CI 1.00, 1.14, P=0.04) presented an increased prevalence of CRN. Subgroup analyses revealed that high levels of serum TC (RR=1.04; 95% CI 1.01, 1.09, P=0.02), TAG (RR=1.06; 95% CI 1.03, 1.10, P=0.0009) and LDL-C (RR=1.11; 95% CI 1.04, 1.19, P=0.003) increased the risk of CRA but not of CRC. No association between serum HDL-C and risk for CRN (including CRA and CRC) was observed.Conclusions: Both TAG and LDL-C were significantly associated with an increasing prevalence of CRN. High levels of serum TC, TAG and LDL-C were positively associated with CRA but not with CRC. No significant association was observed between levels of serum HDL-C and CRN. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
38. Synergistic effect of fermentable and non-fermentable carbon sources enhances TAG accumulation in oleaginous yeast Rhodosporidium kratochvilovae HIMPA1.
- Author
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Patel, Alok, Pruthi, Vikas, Singh, Rajesh P., and Pruthi, Parul A.
- Subjects
- *
YEAST , *LIPIDS , *GLYCERIN , *GLUCOSE , *FATTY acids - Abstract
Novel strategy for enhancing TAG accumulation by simultaneous utilization of fermentable and non-fermentable carbon sources as substrate for cultivation of oleaginous yeast Rhodosporidium kratochvilovae HIMPA1 were undertaken in this investigation. The yeast strain showed direct correlation between the size of lipid bodies, visualized by BODIPY stain (493–515 nm) and TAG accumulation when examined on individual fermenting and non-fermenting carbon sources and their mixtures. Maximum TAG accumulation (μm) in glucose (2.38 ± 0.52), fructose (4.03 ± 0.38), sucrose (4.24 ± 0.45), glycerol (4.35 ± 0.54), xylulose (3.94 ± 0.12), and arabinose (2.98 ± 0.43) were observed. Synergistic effect of the above carbon sources (fermentable and non-fermentable) in equimolar concentration revealed maximum lipid droplet size of 5.35 ± 0.76 μm and cell size of 6.89 ± 0.97 μm. Total lipid content observed in mixed carbon sources was 9.26 g/l compared to glucose (6.2 g/l). FAME profile revealed enhanced longer chain (C 14:0 -C 24:0 ) fatty acids in mix carbon sources. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
39. Chronic muscle stimulation improves insulin sensitivity while increasing subcellular lipid droplets and reducing selected diacylglycerol and ceramide species in obese Zucker rats.
- Author
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Holloway, Graham, Han, Xiao, Jain, Swati, Bonen, Arend, and Chabowski, Adrian
- Abstract
Aims/hypothesis: Although insulin resistance has been associated with accumulations of specific intramuscular fatty acids and altered subcellular localisation of lipid droplets, these concepts remain controversial. Therefore, we aimed to identify specific intramuscular fatty acids and subcellular lipid localisations associated with improved insulin sensitivity following chronic muscle contraction. Methods: In lean and insulin-resistant obese Zucker rats the tibialis anterior muscle was stimulated (6 h/day for 6 days). Thereafter, muscles were examined for insulin sensitivity, intramuscular lipid droplet localisation and triacylglycerol (TAG), diacylglycerol (DAG) and ceramide fatty acid composition. Results: In lean and obese animals, regardless of muscle type, chronic muscle contraction improved muscle insulin sensitivity and increased intramuscular levels of total and most C14-C22 TAG fatty acids ( p < 0.05). Therefore, accumulation in subcellular lipid droplet compartments reflected the oversupply of lipids within muscle. In contrast, improvements in insulin sensitivity induced by muscle contraction were associated with reductions in specific DAG and ceramide species that were not uniform in red and white muscle of obese rats. However, these reductions were insufficient to fully normalise insulin sensitivity, indicating that other mechanisms are involved. Conclusions/interpretation: Reductions in 18 C length DAG and ceramide species were the most consistent in red and white muscle and therefore may represent therapeutic targets for improving insulin sensitivity. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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- View/download PDF
40. A predicted transmembrane region in plant diacylglycerol acyltransferase 2 regulates specificity toward very-long-chain acyl-CoAs
- Author
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Simon, Jeppson, Helena, Mattisson, Kamil, Demski, and Ida, Lager
- Subjects
diacylglycerol ,DAG ,Brassica napus ,food and beverages ,Lipids ,Substrate Specificity ,lipid ,TAG ,plant biochemistry ,acyltransferase ,Kennedy pathway ,Acyl Coenzyme A ,plant lipids ,Cloning, Molecular ,triacylglycerol ,enzyme specificity ,DGAT2 ,Plant Proteins - Abstract
Triacylglycerols are the main constituent of seed oil. The specific fatty acid composition of this oil is strongly impacted by the substrate specificities of acyltransferases involved in lipid synthesis, such as the integral membrane enzyme diacylglycerol acyltransferase (DGAT). Two forms of DGAT, DGAT1 and DGAT2, are thought to contribute to the formation of seed oil, and previous characterizations of various DGAT2 enzymes indicate that these often are associated with the incorporation of unusual fatty acids. However, the basis of DGAT2's acyl-donor specificity is not known because of the inherent challenges of predicting structural features of integral membrane enzymes. The recent characterization of DGAT2 enzymes from Brassica napus reveals that DGAT2 enzymes with similar amino acid sequences exhibit starkly contrasting acyl-donor specificities. Here we have designed and biochemically tested a range of chimeric enzymes, substituting parts of these B. napus DGAT2 enzymes with each other, allowing us to pinpoint a region that dramatically affects the specificity toward 22:1-CoA. It may thus be possible to redesign the acyl-donor specificity of DGAT2 enzymes, potentially altering the fatty acid composition of seed oil. Further, the characterization of a DGAT2 chimera between Arabidopsis and B. napus demonstrates that the specificity regulated by this region is transferrable across species. The identified region contains two predicted transmembrane helices that appear to reoccur in a wide range of plant DGAT2 orthologues, suggesting that it is a general feature of plant DGAT2 enzymes.
- Published
- 2020
41. Postprandial lipid responses to standard carbohydrates used to determine glycaemic index values.
- Author
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Vega-López, Sonia, Ausman, Lynne M., Matthan, Nirupa R., and Lichtenstein, Alice H.
- Subjects
BLOOD sugar ,CHOLESTEROL ,COMPARATIVE studies ,FATTY acids ,CARBOHYDRATE content of food ,GLUCOSE ,GLYCEMIC index ,HIGH density lipoproteins ,INGESTION ,INSULIN ,LIPIDS ,LOW density lipoproteins ,PROBABILITY theory ,RESEARCH funding ,T-test (Statistics) ,TRIGLYCERIDES ,REPEATED measures design ,DATA analysis software ,DESCRIPTIVE statistics - Abstract
Prior studies assessing the metabolic effects of different types of carbohydrates have focused on their glycaemic response. However, the response of postprandial cardiometabolic risk indicators has not been considered in these studies. The present study assessed postprandial lipid responses to two forms of carbohydrates used as reference foods for glycaemic index determinations, white bread (50 g available carbohydrate) and glucose (50 g), under controlled conditions and with intra-individual replicate determinations. A total of twenty adults (20–70 years) underwent two cycles of challenges with each pair of reference foods (four challenges/person), administered in a random order on separate days under standard conditions. Serum lipids (total cholesterol, LDL-cholesterol, HDL-cholesterol, TAG and NEFA), glucose and insulin were monitored for 5 h post-ingestion. Oral glucose resulted in greater glycaemic and insulinaemic responses than white bread for the first 90 min and a greater subsequent decline after 120 min (P =0·0001). The initial decline in serum NEFA concentrations was greater after the oral glucose than after the white bread challenge, as was the rebound after 150 min (P =0·001). Nevertheless, the type of carbohydrate had no significant effect on postprandial total cholesterol, LDL-cholesterol and HDL-cholesterol concentrations. Following an initial modest rise in TAG concentrations in response to both challenges, the values dropped below the fasting values for oral glucose but not for the white bread challenge. These data suggest that the type of carbohydrate used to determine the glycaemic index, bread or glucose, has little or modest effects on postprandial plasma cholesterol concentrations. Differences in TAG and NEFA concentrations over the 5 h time period were modest, and their clinical relevance is unclear. [ABSTRACT FROM PUBLISHER]
- Published
- 2013
- Full Text
- View/download PDF
42. Gene–diet interactions on plasma lipid levels in the Inuit population.
- Author
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Rudkowska, Iwona, Dewailly, Eric, Hegele, Robert A., Boiteau, Véronique, Dubé-Linteau, Ariane, Abdous, Belkacem, Giguere, Yves, Chateau-Degat, Marie-Ludivine, and Vohl, Marie-Claude
- Subjects
LIPID metabolism ,CHOLESTEROL ,DIET ,DNA ,FISHER exact test ,FAT content of food ,GENETIC polymorphisms ,GENETICS ,HIGH density lipoproteins ,INGESTION ,INUIT ,LIPIDS ,LONGITUDINAL method ,LOW density lipoproteins ,QUESTIONNAIRES ,REGRESSION analysis ,RESEARCH funding ,TRIGLYCERIDES ,WHITE people ,BODY mass index ,FOOD diaries ,DATA analysis software ,GENOTYPES - Abstract
The Inuit population is often described as being protected against CVD due to their traditional dietary patterns and their unique genetic background. The objective of the present study was to examine gene–diet interaction effects on plasma lipid levels in the Inuit population. Data from the Qanuippitaa Nunavik Health Survey (n 553) were analysed via regression models which included the following: genotypes for thirty-five known polymorphisms (SNP) from twenty genes related to lipid metabolism; dietary fat intake including total fat (TotFat) and saturated fat (SatFat) estimated from a FFQ; plasma lipid levels, namely total cholesterol (TC), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C) and TAG. The results demonstrate that allele frequencies were different in the Inuit population compared with the Caucasian population. Further, seven SNP (APOA1 − 75G/A (rs670), APOB XbAI (rs693), AGT M235T (rs699), LIPC 480C/T (rs1800588), APOA1 84T/C (rs5070), PPARG2 − 618C/G (rs10865710) and APOE 219G/T (rs405509)) in interaction with TotFat and SatFat were significantly associated with one or two plasma lipid parameters. Another four SNP (APOC3 3238C>G (rs5128), CETP I405V (rs5882), CYP1A1 A4889G (rs1048943) and ABCA1 Arg219Lys (rs2230806)) in interaction with either TotFat or SatFat intake were significantly associated with one plasma lipid variable. Further, an additive effect of these SNP in interaction with TotFat or SatFat intake was significantly associated with higher TC, LDL-C or TAG levels, as well as with lower HDL-C levels. In conclusion, the present study supports the notion that gene–diet interactions play an important role in modifying plasma lipid levels in the Inuit population. [ABSTRACT FROM PUBLISHER]
- Published
- 2013
- Full Text
- View/download PDF
43. Optimization of Reaction Conditions in the Enzymatic Interesterification of Soybean Oil and Fully Hydrogenated Soybean Oil to Produce Plastic Fats.
- Author
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Pacheco, Consuelo, Palla, Camila, Crapiste, Guillermo H., and Carrín, María E.
- Subjects
LIPIDS ,SOY oil ,FOOD industry ,MELTING points ,HYDROGENATION ,CRYSTALS - Abstract
Semisolid fats obtained from oils and fats through enzymatic interesterification have interesting applications. The effect of certain reaction parameters (enzyme concentration, moisture content, reaction time, substrate ratio, temperature, and agitation level) over the enzymatic interesterification of fully hydrogenated soybean oil (FHSO) and refined soybean oil (SO) using two immobilized enzyme types (Lipozyme RM IM and Lipozyme TL IM), was studied with a fractional factorial design (FFD). The reaction products were analyzed with respect to melting point (mp), by-products content and triacylglycerols (TAG) composition. It was found that substrate ratio, reaction time, and their interaction presented the most significant contributions to mp, varying this from 43.4 to 61.5 °C. The highest contributions to by-product content were presented by time and its interaction with the amount of molecular sieves, mainly for Lipozyme TL IM. Through the models obtained, theoretical conditions to achieve minimal by-product generation and mp were found, being 5.0 % (w/w) of any of both lipases, 24 h, 70:30 (oil:fat, % w/w), 65 °C, 230 rpm, and absence of molecular sieves. Regression models for TAG groups as a function of significant factors and interactions were constructed, offering useful information to establish the reaction conditions for obtaining a product with a target mp or chemical composition. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
44. The lipid-lowering effect of dietary proanthocyanidins in rats involves both chylomicron-rich and VLDL-rich fractions.
- Author
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Quesada, Helena, Díaz, Sabina, Pajuelo, David, Fernández-Iglesias, Anabel, Garcia-Vallvé, Santiago, Pujadas, Gerard, Salvadó, M. Josepa, Arola, Lluis, and Bladé, Cinta
- Subjects
FLAVONOIDS ,THERAPEUTIC use of plant extracts ,RNA analysis ,ANALYSIS of variance ,ANIMAL experimentation ,GRAPES ,INGESTION ,LIPIDS ,LIPOPROTEINS ,RATS ,RESEARCH funding ,T-test (Statistics) ,TRIGLYCERIDES ,DATA analysis software ,GENE expression profiling ,THERAPEUTICS - Abstract
Proanthocyanidins have been shown to improve postprandial hypertriacylglycerolaemia. The present study aims to determine the actual contribution of chylomicrons (CM) and VLDL in the hypotriacylglycerolaemic action of grape seed proanthocyanidin extract (GSPE) in the postprandial state and to characterise the mechanisms by which the GSPE treatment reduces TAG-rich lipoproteins in vivo. A plasma lipid tolerance test was performed on rats fasted for 14 h and orally loaded with lard containing either GSPE or not. GSPE (250 mg/kg body weight) markedly blocked the increase in plasma TAG induced by lard, with a statistically significant reduction of 22 % in the area under the curve. The VLDL-rich fraction was the major contributor (72 %) after 1 h, whereas the CM-rich fraction was the major contributor (85 %) after 3 h. At 5 and 7 h after treatment, CM-rich and VLDL-rich fractions showed a similar influence. Plasma post-heparin lipoprotein lipase (LPL) activity and LPL mRNA levels in white adipose tissue and muscle were not affected by GSPE. On the contrary, GSPE treatment significantly repressed (30 %) the secretion of VLDL-TAG. In the liver, GSPE treatment induced different effects on the expression of acyl-coenzyme A synthetase long-chain family member 1, Apoc3 and 3-hydroxy-3-methylglutaryl-coenzyme A reductase at 1 h and Cd36 at 5 h, compared to those induced by lard. Furthermore, GSPE treatment significantly increased the activity of carnitine palmitoyltransferase 1a at 1 h. In conclusion, both CM-rich and VLDL-rich fractions contributed to the hypotriacylglycerolaemic action of GSPE, but their influence depended on time. GSPE induces hypotriacylglycerolaemic actions by repressing lipoprotein secretion and not by increasing LPL activity. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
- Full Text
- View/download PDF
45. The Chain Length of Dietary Saturated Fatty Acids Affects Human Postprandial Lipemia.
- Author
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Karupaiah, Tilakavati, Tan, Choon, Chinna, Karuthan, and Sundram, Kalyana
- Subjects
LIPIDS ,LIPOPROTEINS ,FAT ,ATHEROSCLEROSIS ,HYPERTENSION - Abstract
The article discusses a study to evaluate the postprandial effect of varying chain length saturation of dietary fats on lipids and lipoproteins. Data gathered from 20 healthy participants aged between 22 to 38 years with no history of atherosclerotic disease or hypertension indicate that the individual nature of dietary saturates variably affected the fat digestion and absorption in the test participants.
- Published
- 2011
- Full Text
- View/download PDF
46. H- and C-NMR Characterization of the Molecular Components of the Lipid Fraction of Pecorino Sardo Cheese.
- Author
-
Scano, P., Anedda, R., Melis, M., Dessi', M., Lai, A., and Roggio, T.
- Subjects
PECORINO cheese ,LIPIDS ,FATTY acids ,DIGLYCERIDES ,NUCLEAR magnetic resonance spectroscopy ,LINOLEIC acid ,PEROXIDES - Abstract
In this work the molecular fatty components of Pecorino Sardo Protected Designation of Origin (PS PDO) cheese were characterized through an exhaustive investigation of the H- and C-NMR spectra of the extracted lipids. Several fatty acids (FA), such as long chain saturated, oleic, linoleic, linolenic, butyric, capric, caprylic, caproic, trans vaccenic, conjugated linoleic acid ( cis9, trans11-18:2), and caproleic (9-10:1) were unambiguously detected. The positional isomery of some acyl groups in the glycerol backbone of triacylglycerols (TAG) was assessed. Furthermore, the NMR signals belonging to sn-1,2/2,3, sn-1,3 diacylglycerols (DAG), and free fatty acids (FFA) were analysed as a measure of lipolytic processes on cheese. Lastly, H-NMR resonances of saturated aldehydes and hydroperoxides were detected, their very low intensity indicating that the lipid oxidation process can be considered to be of minor relevance in Pecorino Sardo cheese. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
47. Systematic investigation of biomass and lipid productivity by microalgae in photobioreactors for biodiesel application
- Author
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Pruvost, J., Van Vooren, G., Le Gouic, B., Couzinet-Mossion, A., and Legrand, J.
- Subjects
- *
BIOMASS energy , *LIPIDS , *MICROALGAE , *BIODIESEL fuels , *BIOREACTORS , *SCIENTIFIC method , *CHLORELLA , *SEAWATER , *DIATOMS - Abstract
Abstract: We describe a methodology to investigate the potential of given microalgae species for biodiesel production by characterizing their productivity in terms of both biomass and lipids. A multi-step approach was used: determination of biological needs for macronutrients (nitrate, phosphate and sulphate), determination of maximum biomass productivity (the “light-limited” regime), scaling-up of biomass production in photobioreactors, including a theoretical framework to predict corresponding productivities, and investigation of how nitrate starvation protocol affects cell biochemical composition and triggers triacylglycerol (TAG) accumulation. The methodology was applied to two freshwater strains, Chlorella vulgaris and Neochloris oleoabundans, and one seawater diatom strain, Cylindrotheca closterium. The highest total lipid content was achieved with N. oleoabundans (25–37% of DW), while the highest TAG content was found in C. vulgaris (11–14% of DW). These two species showed similar TAG productivities. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
48. Investigation of biomass and lipids production with Neochloris oleoabundans in photobioreactor
- Author
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Pruvost, J., Van Vooren, G., Cogne, G., and Legrand, J.
- Subjects
- *
BIOMASS production , *LIPIDS , *MICROALGAE , *BIOREACTORS , *PHOTOBIOCHEMISTRY , *ALGAL growth , *EFFECT of nitrogen on plants , *BIODIESEL fuels , *INDUSTRIAL microbiology - Abstract
Abstract: The fresh water microalga Neochloris oleoabundans was investigated for its ability to accumulate lipids and especially triacylglycerols (TAG). A systematic study was conducted, from the determination of the growth medium to its characterization in an airlift photobioreactor. Without nutrient limitation, a maximal biomass areal productivity of 16.5gm−2 day−1 was found. Effects of nitrogen starvation to induce lipids accumulation was next investigated. Due to initial N. oleoabundans total lipids high content (23% of dry weight), highest productivity was obtained without mineral limitation with a maximal total lipids productivity of 3.8gm−2 day−1. Regarding TAG, an almost similar productivity was found whatever the protocol was: continuous production without mineral limitation (0.5gm−2 day−1) or batch production with either sudden or progressive nitrogen deprivation (0.7gm−2 day−1). The decrease in growth rate reduces the benefit of the important lipids and TAG accumulation as obtained in nitrogen starvation (37% and 18% of dry weight, respectively). [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
49. Winter lipid depletion of juvenile walleye pollock Theragra chalcogramma in the Doto area, northern Japan.
- Author
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KOOKA, K., YAMAMURA, O., OHKUBO, N., and HONDA, S.
- Subjects
- *
WALLEYE pollock , *TERRITORIAL waters , *ANIMAL morphology , *LIPIDS - Abstract
Seasonal variation in body size and nutritional condition of juvenile walleye pollock Theragra chalcogramma was examined to elucidate the mechanism underlying their first-winter survival on the continental shelf of the Doto area, northern Japan, based on monthly samples collected over 2 years. Stored lipid mass was highest during autumn, but 93% (2004) and 80% (2005) of lipids were exhausted by the onset of winter. Lipid levels in the winter of 2004 remained low (7–14% of the autumnal maximum), and there was reduced growth rate until the spring, whereas in 2005 lipid levels were higher and more variable (10–46% of the maximum) and some growth occurred. An analysis of the allometric relationships between body size and stored energy showed that larger individuals accumulated disproportionately more energy in the autumn, but the advantage disappeared prior to the winter. In January 2004, stored lipid energy was low throughout the Doto continental shelf relative to the continental slope area. These results suggest that winter feeding opportunities on the shelf are severely limited but not completely absent. Previous studies have shown that winter temperatures on the shelf are lower than those in the slope area. It is possible that juvenile T. chalcogramma survive winter on the shelf without a high level of pre-winter lipid storage because the occasional feeding in the cold shelf water benefits energy conservation. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
50. Lipolytic enzymes in Mycobacterium tuberculosis.
- Author
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Côtes, K., Bakala N’Goma, J., Dhouib, R., Douchet, I., Maurin, D., Carrière, F., and Canaan, S.
- Subjects
- *
ENZYMES , *MYCOBACTERIUM tuberculosis , *PATHOGENIC microorganisms , *GLYCERIN , *ADIPOSE tissues , *LIPIDS , *CELL membranes , *HYDROLYSIS , *GENOMES - Abstract
Mycobacterium tuberculosis is a bacterial pathogen that can persist for decades in an infected patient without causing a disease. In vivo, the tubercle bacillus present in the lungs store triacylglycerols in inclusion bodies. The same process can be observed in vitro when the bacteria infect adipose tissues. Indeed, before entering in the dormant state, bacteria accumulate lipids originating from the host cell membrane degradation and from de novo synthesis. During the reactivation phase, these lipids are hydrolysed and the infection process occurs. The degradation of both extra and intracellular lipids can be directly related to the presence of lipolytic enzymes in mycobacteria, which have been ignored during a long period particularly due to the difficulties to obtain a high expression level of these enzymes in M. tuberculosis. The completion of the M. tuberculosis genome offered new opportunity to this kind of study. The aim of this review is to focus on the recent results obtained in the field of mycobacterium lipolytic enzymes and although no experimental proof has been shown in vivo, it is tempting to speculate that these enzymes could be involved in the virulence and pathogenicity processes. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
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