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Maximal oxygen uptake (VO2max) is a determining indicator for cardiorespiratory capacity in endurance athletes, and epigenetics is crucial in its levels and variability. This initial study examined a broad plasma miRNA profile of twenty-three trained elite endurance athletes with similar training volumes but different VO2max in response to an acute maximal graded endurance test. Six were clustered as higher/lower levels based on their VO2max (75.4 ± 0.9 and 60.1 ± 5.0 mL.kg-1.min-1). Plasma was obtained from athletes before and after the test and 15 ng of total RNA was extracted and detected using an SYBR-based 1113 miRNA RT-qPCR panel. A total of 51 miRNAs were differentially expressed among group comparisons. Relative amounts of miRNA showed a clustering behavior among groups regarding distinct performance/time points. Significantly expressed miRNAs were used to perform functional bioinformatic analysis (DIANA tools). Fatty acid metabolism pathways were strongly targeted for the significantly different miRNAs in all performance groups and time points (p < 0.001). Although this pathway does not solely determine endurance performance, their significant contribution is certainly achieved through the involvement of miRNAs. A highly genetically dependent gold standard variable for performance evaluation in a homogeneous group of elite athletes allowed genetic/epigenetic aspects related to fatty acid pathways to emerge.

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In the present work we aimed to study the effects of parenteral vitamin and mineral supplementation on hepatic fatty acid metabolism as well as on the oxidative stress biomarkers in biological samples of transition cows. The supplemented group (SG, n = 11) received a subcutaneous injection of 5 mL of vitamin A palmitate 35 mg/mL, vitamin E acetate 50 mg/mL plus other injection of 5 mL of copper edetate 10 mg/mL, zinc edetate 40 mg/mL, manganese edetate 10 mg/mL, and sodium selenite 5 mg/mL on days - 60, - 30, and 7 (± 3) relative to calving. The control group (CG, n = 11) received two subcutaneous injections of 5 mL of 9 mg/mL sodium chloride at the same times of the SG. Blood, urine, and liver biopsies were sampled 21 (± 3) days before the expected calving date and 7 and 21 (± 3) days after calving. Results revealed that supplemented animals had higher glutation peroxidase (GSH-Px) activity, lower and higher concentration of 3-nitrotyrosine (3-NT) in the liver and plasma, respectively, higher expression of the mitochondrial beta-oxidation enzyme carnitine palmitoyltransferase 1 in the liver, and lower content of hepatic triacylglycerol, mirroring plasma liver function parameters. No differences between groups were found in the superoxide dismutase activity, MDA concentrations, the protein abundance of peroxisomal acyl-CoA oxidase 1, diacylglycerol O-acyltransferase 1, and peroxisome proliferator-activated receptor alpha. These results suggest that the vitamin and mineral supplementation provided to dairy cows had a beneficial effect on GSH-Px activity, hepatic 3-NT concentration, and on the metabolic adaptation during the peripartum period.

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PURPOSE: Metabolic reprogramming is a novel hallmark and therapeutic target of cancer. Our study aimed to establish fatty acid metabolism-associated scores based on gene signature and investigated its effects on immunotherapy in colon cancer. METHODS: Gene expression and clinical information were collected from Gene Expression Omnibus (GEO) database to identify a gene signature by non-negative matrix factorization (NMF) clustering and Cox regression analysis. Subsequently, we constructed the fatty acid metabolism score (FA-score) model by principal component analysis (PCA) and explored its relativity of prognosis and the response to immunotherapy in colon cancer. Finally, the Cancer Genome Atlas (TCGA) database was introduced and in vitro study was performed for verification. RESULTS: The FA-score-high group had a higher level of fatty acid metabolism and was associated with worse patient overall survival. Significantly, FA-score correlated closely with the biomarkers of immunotherapy, and the FA-score-high group had a poorer therapeutic efficacy of immune checkpoint blockade. In vitro experiments demonstrated that ACSL5 may be a critical metabolic regulatory target. CONCLUSIONS: Our study provided a comprehensive analysis of the heterogeneity of fatty acid metabolism in colon cancer. We highlighted the potential clinical utility of fatty acid metabolism-related genes to be biomarkers of colon cancer prognosis and targets to improve the effect of immunotherapy.

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INTRODUCTION AND OBJECTIVES: Hepatocellular carcinoma (HCC), a malignancy with a very dismal prognosis, has drawn a lot of attention, particularly in East Asia, where morbidity and mortality are higher. Although new information about the role of fatty acids (FAs) in HCC is constantly being discovered, it is still vital to investigate how FA metabolism affects the prognosis, immune microenvironment, and responsiveness of HCC to immunotherapy as a whole. MATERIALS AND METHODS: To determine the significance of FA metabolism in HCC immunotherapy, we first evaluated HCC samples from the single-cell dataset GSE151530. The TCGA-LIHC cohort and GSE140901 were further studied to identify the impact of FA metabolism on prognosis, immune microenvironment, drug sensitivity, and immunotherapy response by developing a fatty acid prediction index (FPI). The heterogeneity and similarity of the involvement of FA metabolism in pan-cancer is also investigated. RESULTS: Combining single-cell and bulk analyses, we confirmed that FA metabolism regulates tumor malignancy, prognosis, immune microenvironment, drug sensitivity, and immunotherapy response in patients with HCC. Moreover, it can have a considerable impact on the physiological activities of hepatocellular cancer. In addition, we demonstrate that FA metabolism has a comparable or same role in many malignancies. CONCLUSIONS: Our investigation shows the crucial regulatory role of FA metabolism in HCC and suggests a potential therapeutic method for HCC patients, which may improve their survival.

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Abstract Background: CTHRC1 is highly expressed in various cancers. Objectives: The aim of the study was to study the role of CTHRC1 played in lung adenocarcinoma (LUAD) development and its underlying biological functions. Methods: Enriched pathways and upstream transcription factors of CTHRC1 were explored by bioinformatics analysis. Dual-luciferase assay and Chromatin immunoprecipitation assay were used to verify the binding relationship between CTHRC1 and HOXB9. CCK-8 was utilized to detect cell viability. Expression levels of CTHRC1, HOXB9, and angiogenesis-related genes were assessed by quantitative real time-polymerase chain reaction. Angiogenesis assay was used to detect angiogenesis ability. Quantitative analysis of metabolites were used to detect the accumulation of neutral lipids, the levels of free fatty acids (FAs), and glycerol. Western blot was conducted to measure expression of metabolic enzymes of FA. Results: CTHRC1 was enriched in FA metabolic pathway, which was positively correlated and bound with HOXB9. CTHRC1 and HOXB9 expression was remarkably up-regulated in LUAD cells. Overexpression of CTHRC1 promoted FA metabolic pathway and angiogenesis, and FA inhibitor Orlistat restored it to NC group level. Meanwhile, CTHRC1 affected LUAD angiogenesis by activating HOXB9 to regulate FA metabolism. Conclusions: This study found that activation of CTHRC1 by HOXB9 induces angiogenesis by mediating FA metabolism. CTHRC1 may be a potential target for LUAD diagnosis.

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Fatty acid (FA) metabolism dysfunction of white adipose tissue (WAT) underlies obesity and insulin resistance in response to high calorie intake and/or endocrine-disrupting chemicals (EDCs), among other factors. Arsenic is an EDC that has been associated with metabolic syndrome and diabetes. However, the combined effect of a high-fat diet (HFD) and arsenic exposure on WAT FA metabolism has been little studied. FA metabolism was evaluated in visceral (epididymal and retroperitoneal) and subcutaneous WAT of C57BL/6 male mice fed control or HFD (12 and 40% kcal fat, respectively) for 16 weeks together with an environmentally relevant chronic arsenic exposure through drinking water (100 µg/L) during the second half of the study. In mice fed HFD, arsenic potentiated the increase of serum markers of selective insulin resistance in WAT and fatty acid re-esterification and the decrease of the lipolysis index. Retroperitoneal was the WAT most affected, where the combination of arsenic and HFD in contrast to HFD, generated higher adipose weight, larger adipocytes, increased triglyceride content, and decreased fasting stimulated lipolysis evidenced by lower phosphorylation of HSL and perilipin. At the transcriptional level, arsenic in mice fed either diet downregulated genes involved in fatty acid uptake (LPL, CD36), oxidation (PPARα, CPT1), lipolysis (ADRß3) and glycerol transport (AQP7 and AQP9). Additionally, arsenic potentiated hyperinsulinemia induced by HFD, despite a slight increase in weight gain and food efficiency. Thus, the second hit of arsenic in sensitized mice by HFD worsens fatty acid metabolism impairment in WAT, mainly retroperitoneal, along with an exacerbated insulin resistance phenotype.

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Serine palmitoyltransferase (SPT) catalyzes the first and committed step in sphingolipid biosynthesis condensating L-serine and acyl-CoA to form 3-oxo-sphinganine. Whenever the structural gene for SPT is present in genomes of Rhodobacteria (α-, ß-, and γ-Proteobacteria), it co-occurs with genes coding for a putative acyl carrier protein (ACP) and a putative acyl-CoA synthetase (ACS). In the α-proteobacterium Caulobacter crescentus, CC_1162 encodes an SPT, whereas CC_1163 and CC_1165 encode the putative ACP and ACS, respectively, and all three genes are known to be required for the formation of the sphingolipid intermediate 3-oxo-sphinganine. Here we show that the putative ACP possesses a 4'-phosphopantetheine prosthetic group, is selectively acylated by the putative ACS and therefore is a specialized ACP (AcpR) required for sphingolipid biosynthesis in Rhodobacteria. The putative ACS is unable to acylate coenzyme A or housekeeping ACPs, but acylates specifically AcpR. Therefore, it is a specialized acyl-ACP synthetase (AasR). SPTs from C. crescentus, Escherichia coli B, or Sphingomonas wittichii use preferentially acyl-AcpR as thioester substrate for 3-oxo-sphinganine synthesis. Whereas acyl-AcpR from C. crescentus is a good substrate for SPTs from distinct Rhodobacteria, acylation of a specific AcpR is achieved by the cognate AasR from the same bacterium. Rhodobacteria might use this more complex way of 3-oxo-sphinganine formation in order to direct free fatty acids toward sphingolipid biosynthesis.

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Saroglitazar, being a dual PPAR-α/γ agonist, has shown beneficial effect in diabetic dyslipidemia and hypertriglyceridemia. Fibrates are commonly used to treat severe hypertriglyceridemia. However, the effect of saroglitazar in patients with moderate to severe hypertriglyceridemia was not evaluated. We conducted a study to compare the efficacy and safety of saroglitazar (4 mg) with fenofibrate (160 mg) in patients with moderate to severe hypertriglyceridemia. This was a multicenter, randomized, double-blinded, double-dummy, active-control, and noninferiority trial in adult patients with fasting triglyceride (TG) levels of 500-1,500 mg/dl. The patients were randomized in a 1:1 ratio to receive daily dose of saroglitazar or fenofibrate for 12 weeks. The primary efficacy end point was the percent change in TG levels at week 12 relative to baseline. The study comprised of 41 patients in the saroglitazar group and 41 patients in the fenofibrate group. We found that the percent reduction from baseline in TG levels at week 12 was significantly higher in the saroglitazar group (least square mean = -55.3%; SE = 4.9) compared with the fenofibrate group (least square mean = -41.1%; SE = 4.9; P = 0.048). Overall, 37 treatment-emergent adverse events (AEs) were reported in 24 patients (saroglitazar: 13; fenofibrate: 11). No serious AEs were reported, and no patient discontinued the study because of AEs. We conclude that saroglitazar (4 mg) is noninferior to fenofibrate (160 mg) in reducing TG levels after 12 weeks of treatment, was safe, and well tolerated.

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Background: CTHRC1 is highly expressed in various cancers. Objectives: The aim of the study was to study the role of CTHRC1 played in lung adenocarcinoma (LUAD) development and its underlying biological functions. Methods: Enriched pathways and upstream transcription factors of CTHRC1 were explored by bioinformatics analysis. Dual-luciferase assay and Chromatin immunoprecipitation assay were used to verify the binding relationship between CTHRC1 and HOXB9. CCK-8 was utilized to detect cell viability. Expression levels of CTHRC1, HOXB9, and angiogenesis-related genes were assessed by quantitative real time-polymerase chain reaction. Angiogenesis assay was used to detect angiogenesis ability. Quantitative analysis of metabolites were used to detect the accumulation of neutral lipids, the levels of free fatty acids (FAs), and glycerol. Western blot was conducted to measure expression of metabolic enzymes of FA. Results: CTHRC1 was enriched in FA metabolic pathway, which was positively correlated and bound with HOXB9. CTHRC1 and HOXB9 expression was remarkably up-regulated in LUAD cells. Overexpression of CTHRC1 promoted FA metabolic pathway and angiogenesis, and FA inhibitor Orlistat restored it to NC group level. Meanwhile, CTHRC1 affected LUAD angiogenesis by activating HOXB9 to regulate FA metabolism. Conclusions: This study found that activation of CTHRC1 by HOXB9 induces angiogenesis by mediating FA metabolism. CTHRC1 may be a potential target for LUAD diagnosis.

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The objective of this study was to investigate the effects of recombinant adiponectin on chicken liver cells. The full-length chicken adiponectin gene was amplified by PCR and cloned into the vector pET-32a, followed by the transformation of the vector into Escherichia coli BL21. SDS-PAGE was used to detect and analyze the purity of the expressed recombinant protein. Induction was performed with 1 mM IPTG at 30 °C for 3 h, and the recombinant thioredoxin­adiponectin fusion protein was purified using Ni-NTA affinity chromatography. Chicken adiponectin was successfully expressed and purified in a bacterial system. In addition, the chicken recombinant adiponectin demonstrated that it ameliorates palmitic acid- and oleic acid-induced adipogenesis, in which an increase in ß-oxidation and a decrease in lipogenesis-related genes may be involved. In summary, chicken recombinant adiponectin enhances fatty acid metabolism in LMH cells.(AU)

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The study aimed to evaluate the supplementation of gilts with cow's milk naturally enriched with n-3 and n-6 polyunsaturated fatty acids (PUFA) on reproductive outcomes, and the serum biochemical and FA profile of swine females and their offspring. During 316 days, 30 gilts were distributed into three groups: (1) Control, fed a basal diet + milk from cows without oil; (2) n-3, fed a basal diet + milk from cows fed a diet enriched with linseed oil; (3) n-6, fed a basal diet + milk from cows fed a diet enriched with soybean oil. The gilts receiving the diets containing PUFA had higher serum urea and very-low-density lipoprotein levels and lower serum total protein and low-density lipoprotein levels compared to the Control group. Females supplemented with n-3 presented higher serum palmitic acid and γ-linolenic acid levels than those fed n-6. Piglets from the Control group were heavier at birth than those from females supplemented with enriched milk. The piglets from females receiving enriched milk had 140 g higher body weight from 1 to 21 days old compared to the Control group, and greater average daily weight gain from 7 to 14 days old. The serum eicosapentaenoic acid level of piglets fed n-3 was 69% higher than those fed n-6, which reduced the AA/EPA ratio. Gilts supplemented with PUFA-enriched cow's milk showed changes in their serum palmitic and γ-linolenic acid levels, in addition to improved performance, EPA concentration and consequently reduced AA/EPA ratio in their piglets, demonstrating beneficial results for their progeny.

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PURPOSE: In contrast to hormone receptor driven breast cancer, patients presenting with triple-negative breast cancer (TNBC) often have limited drug treatment options. Efavirenz, a non-nucleoside reverse transcriptase (RT) inhibitor targets abnormally overexpressed long interspersed nuclear element 1 (LINE-1) RT and has been shown to be a promising anticancer agent for treating prostate and pancreatic cancers. However, its effectiveness in treating patients with TNBC has not been comprehensively examined. METHODS: In this study, the effect of Efavirenz on several TNBC cell lines was investigated by examining several cellular characteristics including viability, cell division and death, changes in cell morphology as well as the expression of LINE-1. RESULTS: The results show that in a range of TNBC cell lines, Efavirenz causes cell death, retards cell proliferation and changes cell morphology to an epithelial-like phenotype. In addition, it is the first time that a whole-genome RNA sequence analysis has identified the fatty acid metabolism pathway as a key regulator in this Efavirenz-induced anticancer process. CONCLUSION: In summary, we propose Efavirenz is a potential anti-TNBC drug and that its mode of action can be linked to the fatty acid metabolism pathway.

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Abstract: Prenatal and postnatal development are closely related to healthy maternal conditions that allow for the provision of all nutritional requirements to the offspring. In this regard, an appropriate supply of fatty acids (FA), mainly n-3 and n-6 long-chain polyunsaturated fatty acids (LCPUFA), is crucial to ensure a normal development, because they are an integral part of cell membranes and participate in the synthesis of bioactive molecules that regulate multiple signaling pathways. On the other hand, maternal obesity and excessive gestational weight gain affect FA supply to the fetus and neonate, altering placental nutrient transfer, as well as the production and composition of breast milk during lactation. In this regard, maternal obesity modifies FA profile, resulting in low n-3 and elevated n-6 PUFA levels in maternal and fetal circulation during pregnancy, as well as in breast milk during lactation. These modifications are associated with a pro-inflammatory state and oxidative stress with short and long-term consequences in different organs of the fetus and neonate, including in the liver, brain, skeletal muscle, and adipose tissue. Altogether, these changes confer to the offspring a higher risk of developing obesity and its complications, as well as neuropsychiatric disorders, asthma, and cancer. Considering the consequences of an abnormal FA supply to offspring induced by maternal obesity, we aimed to review the effects of obesity on the metabolism and bioavailability of FA during pregnancy and breastfeeding, with an emphasis on LCPUFA homeostasis.

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Lipoic acid (LA) is a sulfur-containing cofactor that covalently binds to a variety of cognate enzymes that are essential for redox reactions in all three domains of life. Inherited mutations in the enzymes that make LA, namely lipoyl synthase, octanoyltransferase, and amidotransferase, result in devastating human metabolic disorders. Unfortunately, because many aspects of this essential pathway are still obscure, available treatments only serve to alleviate symptoms. We envisioned that the development of an organismal model system might provide new opportunities to interrogate LA biochemistry, biology, and physiology. Here we report our investigations on three Caenorhabditis elegans orthologous proteins involved in this post-translational modification. We established that M01F1.3 is a lipoyl synthase, ZC410.7 an octanoyltransferase, and C45G3.3 an amidotransferase. Worms subjected to RNAi against M01F1.3 and ZC410.7 manifest larval arrest in the second generation. The arrest was not rescued by LA supplementation, indicating that endogenous synthesis of LA is essential for C. elegans development. Expression of the enzymes M01F1.3, ZC410.7, and C45G3.3 completely rescue bacterial or yeast mutants affected in different steps of the lipoylation pathway, indicating functional overlap. Thus, we demonstrate that, similarly to humans, C. elegans is able to synthesize LA de novo via a lipoyl-relay pathway, and suggest that this nematode could be a valuable model to dissect the role of protein mislipoylation and to develop new therapies.

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Metabolic deregulation is an emergent hallmark of cancer. Altered patterns of metabolic pathways result in exacerbated synthesis of macromolecules, increased proliferation, and resistance to treatment via alteration of drug processing. In addition, molecular heterogeneity creates a barrier to therapeutic options. In breast cancer, this broad variation in molecular metabolism constitutes, simultaneously, a source of prognostic and therapeutic challenges and a doorway to novel interventions. In this work, we investigated the metabolic deregulation landscapes in breast cancer molecular subtypes. Such landscapes are the regulatory signatures behind subtype-specific metabolic features. n = 735 breast cancer samples of the Luminal A, Luminal B, Her2+, and Basal subtypes, as well as n = 113 healthy breast tissue samples were analyzed. By means of a single-sample-based algorithm, deregulation for all metabolic pathways in every sample was determined. Deregulation levels match almost perfectly with the molecular classification, indicating that metabolic anomalies are closely associated with gene-expression signatures. Luminal B tumors are the most deregulated but are also the ones with higher within-subtype variance. We argued that this variation may underlie the fact that Luminal B tumors usually present the worst prognosis, a high rate of recurrence, and the lowest response to treatment in the long term. Finally, we designed a therapeutic scheme to regulate purine metabolism in breast cancer, independently of the molecular subtype. This scheme is founded on a computational tool that provides a set of FDA-approved drugs to target pathway-specific differentially expressed genes. By providing metabolic deregulation patterns at the single-sample level in breast cancer subtypes, we have been able to further characterize tumor behavior. This approach, together with targeted therapy, may open novel avenues for the design of personalized diagnostic, prognostic, and therapeutic strategies.

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The liver is an essential organ for body energy homeostasis, controlling the biosynthesis, uptake and the disposal of carbohydrates and lipids. The hepatic steatosis is a common condition frequently associated with metabolic diseases and is characterized by the excessive accumulation of triglycerides in the liver. In recent years, many efforts have been devoted to prevent and treat the hepatic steatosis, but it remains being pointed out as the major cause for chronic hepatic diseases in Western countries. A considerable part of the knowledge about the physiopathology of hepatic steatosis, the effects of diets and drugs on the metabolic capacity of the liver to metabolize fatty acids, as well as the potential therapeutic approaches for hepatic steatosis derived from experimental animal models using rodents. Here, in this article, we present the details of some of the most common techniques used to evaluate fatty acid metabolism in liver of rats, including quantification of total lipid content, measurement of fatty acid oxidation in isolated subcellular fractions and procedures to measure the activities of important lipogenic enzymes. Classical protocols previously described to be performed using samples from other tissues were adapted to liver samples and different techniques with equivalent aims were compared. The principles and the advantages in terms of reliability and costs were discussed and the procedures here described can be applied for a low-cost broad evaluation of the fatty acid metabolism in liver of rats submitted to different experimental conditions.

O fígado é um órgão essencial para a homeostase energética, controlando a biossíntese, a captação e a eliminação de carboidratos e lipídios. A esteatose hepática é uma condição frequentemente associada a doenças metabólicas e é caracterizada pelo acúmulo excessivo de triacilgliceróis no fígado. Nos últimos anos, muitos esforços têm sido dedicados para prevenir e tratar a esteatose hepática, mas essa condição continua sendo apontada como a principal causa de doenças hepáticas crônicas em países ocidentais. Uma parte considerável do conhecimento sobre a fisiopatologia da esteatose hepática, sobre os efeitos de dietas e drogas na capacidade metabólica do fígado em metabolizar ácidos graxos, bem como sobre as possíveis abordagens terapêuticas para a esteatose hepática, derivam de estudos com modelos animais experimentais usando roedores. Neste artigo, apresentamos os detalhes de algumas das técnicas que podem ser usadas para avaliar o metabolismo de ácidos graxos no fígado de ratos, incluindo a quantificação do conteúdo lipídico total, medida da oxidação de ácidos graxos em frações subcelulares isoladas e procedimentos para medir as atividades de importantes enzimas lipogênicas. Protocolos clássicos previamente descritos para serem realizados utilizando amostras de outros tecidos foram adaptados para amostras de fígado e diferentes técnicas com objetivos equivalentes foram comparadas. Os princípios e as vantagens em termos de confiabilidade e custos foram discutidos e os procedimentos aqui descritos podem ser aplicados para uma avaliação ampla e de baixo custo do metabolismo de ácidos graxos no fígado de ratos submetidos a diferentes condições experimentais.

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Diatoms play key roles in primary production and carbon fixation at a global scale and in some cases these species live on marine ecosystems impacted by crude oil (CO) spills. Halamphora oceanica, a new diatom species from the Southwest of the Gulf of Mexico was isolated and cultured in the laboratory and was exposed to water accommodated fraction (WAF) of different Maya CO loads at 0.01, 0.1, 1 and 10g/L by 96h. A battery of biomarkers involved in oxidative stress (O2•, H2O2, TBARS, ROOH, RC=O, SOD, CAT, GPx), biotransformation and conjugation (total CYP450 activity and GST) moreover fatty acid (FA) metabolism (FA levels, fatty-acid synthase and acyl-CoA oxidase) were measured. Obtained results suggest that increases of PAHs in the medium (below to EC50) acts as external forces able to turn-on regulatory mechanisms on H. oceanica involved in both, on the PAHs uptake and changing its aerobic metabolism to anaerobic metabolism. However, the growth of this microalgae species evaluated as chlorophyll "a" and pheophytin levels increased as the WAF concentration indicating that PAHs and other hydrosoluble hydrocarbons were used as carbon and energy sources by unidentified enzymes not evaluated in the current study. Our hypothesis was also corroborated by IBRv2. In the current study, we suppose the change from aerobic to anaerobic metabolism as a strategy for Halamphora oceanica survival exposed to petroleum hydrocarbons.

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The liver is an essential organ for body energy homeostasis, controlling the biosynthesis, uptake and the disposal of carbohydrates and lipids. The hepatic steatosis is a common condition frequently associated with metabolic diseases and is characterized by the excessive accumulation of triglycerides in the liver. In recent years, many efforts have been devoted to prevent and treat the hepatic steatosis, but it remains being pointed out as the major cause for chronic hepatic diseases in Western countries. A considerable part of the knowledge about the physiopathology of hepatic steatosis, the effects of diets and drugs on the metabolic capacity of the liver to metabolize fatty acids, as well as the potential therapeutic approaches for hepatic steatosis derived from experimental animal models using rodents. Here, in this article, we present the details of some of the most common techniques used to evaluate fatty acid metabolism in liver of rats, including quantification of total lipid content, measurement of fatty acid oxidation in isolated subcellular fractions and procedures to measure the activities of important lipogenic enzymes. Classical protocols previously described to be performed using samples from other tissues were adapted to liver samples and different techniques with equivalent aims were compared. The principles and the advantages in terms of reliability and costs were discussed and the procedures here described can be applied for a low-cost broad evaluation of the fatty acid metabolism in liver of rats submitted to different experimental conditions.(AU)

O fígado é um órgão essencial para a homeostase energética, controlando a biossíntese, a captação e a eliminação de carboidratos e lipídios. A esteatose hepática é uma condição frequentemente associada a doenças metabólicas e é caracterizada pelo acúmulo excessivo de triacilgliceróis no fígado. Nos últimos anos, muitos esforços têm sido dedicados para prevenir e tratar a esteatose hepática, mas essa condição continua sendo apontada como a principal causa de doenças hepáticas crônicas em países ocidentais. Uma parte considerável do conhecimento sobre a fisiopatologia da esteatose hepática, sobre os efeitos de dietas e drogas na capacidade metabólica do fígado em metabolizar ácidos graxos, bem como sobre as possíveis abordagens terapêuticas para a esteatose hepática, derivam de estudos com modelos animais experimentais usando roedores. Neste artigo, apresentamos os detalhes de algumas das técnicas que podem ser usadas para avaliar o metabolismo de ácidos graxos no fígado de ratos, incluindo a quantificação do conteúdo lipídico total, medida da oxidação de ácidos graxos em frações subcelulares isoladas e procedimentos para medir as atividades de importantes enzimas lipogênicas. Protocolos clássicos previamente descritos para serem realizados utilizando amostras de outros tecidos foram adaptados para amostras de fígado e diferentes técnicas com objetivos equivalentes foram comparadas. Os princípios e as vantagens em termos de confiabilidade e custos foram discutidos e os procedimentos aqui descritos podem ser aplicados para uma avaliação ampla e de baixo custo do metabolismo de ácidos graxos no fígado de ratos submetidos a diferentes condições experimentais.(AU)

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Abstract 3-Hydroxy-3-methylglutaryl-coenzyme A lyase (HMGCL, HMGCL) deficiency is a rare inborn error of ketogenesis. Even if the ketogenic enzyme is fully disrupted, an elevated signal for the ketone body acetoacetic acid is a frequent observation in the analysis of urinary organic acids, at least if derivatization is performed by methylation. We provide an explanation for this phenomenon and trace it back to degradation of the derivatized 3-hydroxy-3-methylglutaric acid and high temperature of the injector of the gas chromatograph.

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BACKGROUND: Pisolithus microcarpus (Cooke & Massee) G. Cunn is a gasteromycete that produces closed basidiocarps in symbiosis with eucalypts and acacias. The fungus produces a complex basidiocarp composed of peridioles at different developmental stages and an upper layer of basidiospores free of the hyphae and ready for wind dispersal upon the rupture of the basidiocarp pellis. During basidiosporogenesis, a process that takes place inside the basidiocarp peridioles, a conspicuous reserve of fatty acids is present throughout development. While several previous studies have described basidiosporogenesis inside peridioles, very little is known about gene expression changes that may occur during this part of the fungal life cycle. The objective of this work was to analyze gene transcription during peridiole and basidiospore development, while focusing specifically on cell cycle progression and lipid metabolism. RESULTS: Throughout different developmental stages of the peridioles we analyzed, 737 genes were regulated between adjacent compartments (>5 fold, FDR-corrected p-value < 0.05) corresponding to 3.49% of the genes present in the P. microcarpus genome. We identified three clusters among the regulated genes which showed differential expression between the peridiole developmental stages and the basidiospores. During peridiole development, transcripts for proteins involved in cellular processes, signaling, and information storage were detected, notably those for coding transcription factors, DNA polymerase subunits, DNA repair proteins, and genes involved in chromatin structure. For both internal embedded basidiospores (hereto referred to as "Internal spores", IS) and external free basidiospores (hereto referred to as "Free spores", FS), upregulated transcripts were found to involve primary metabolism, particularly fatty acid metabolism (FA). High expression of transcripts related to ß-oxidation and the glyoxylate shunt indicated that fatty acids served as a major carbon source for basidiosporogenesis. CONCLUSION: Our results show that basidiocarp formation in P. microcarpus involves a complex array of genes that are regulated throughout peridiole development. We identified waves of transcripts with coordinated regulation and identified transcription factors which may play a role in this regulation. This is the first work to describe gene expression patterns during basidiocarp formation in an ectomycorrhizal gasteromycete fungus and sheds light on genes that may play important roles in the developmental process.

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