Generation Of Free Fatty Acids Research Articles

Kinetic analysis and back propagation neural network model for shelf-life estimation of stabilized rice bran

To establish a general model for predicting shelf-life of stabilized rice bran, different samples with varying residual enzyme activity, water activity (aw), and packaging materials were used, and hot air assisted-radio frequency (HA-RF) heating was applied as stabilization method. Free fatty acids (FFA) were recorded during storage at different temperatures and kinetic analysis was conducted to compare the effects of different conditions on rice bran shelf-life. FFA content increased rapidly during storage, and higher aw and lipase (LA) activity corresponded to a higher FFA generation rate. Only the increase in FFA of samples with low LA activity (≤30 mg/g) and aw (≤0.3) conformed to Zero-order model, while that of other samples conformed to Fractional Conversion model. For the inhibitory effect of packaging materials on the generation of FFA, BOPP/Kraft-paper/PE > PA/PE > PET/PE > LDPE. A back propagation neural network (BPNN) model was also constructed to predict rice bran shelf-life, which employing LA activity, aw, packaging materials, and storage temperature as input parameters. The BPNN model trained by Levenberg–Marquardt achieved the best prediction performance, with coefficient of determination (R2) of 0.996 and root mean square error (RMSE) of 2.077. Rice bran packaged by BOPP/Kraft-paper/PE with LA activity of 20 mg/g and aw of 0.2 had the longest shelf-life of 147 d at 25 °C. This model is of great help in predicting the shelf-life of stabilized rice bran and guiding the development of rice bran stabilization process.

Effect of Ageing of Rolling Oil on the Performance of Cold‐Rolled Steel

ABSTRACTInteraction between the cold rolling oil and substrate at the roll bite has always intrigued the tribologists. In plant conditions, it has been observed that occurrences of surface defects on cold‐rolled FHCR coils increase with the ageing of cold rolling emulsion. In this study, the rolling oil was aged at different lab conditions to replicate 6 and 11 months of rolling oil ageing from a particular cold rolling mill. The studies indicated an increase in acid number of the oil. Tribological studies indicated an increase in CoF along with an increase in wear phenomenon on the substrate. The removability of the surface oil becomes difficult with ageing which could lead to potential surface oil residues remaining on the strip after degreasing, resulting in surface defects and dirty coils after annealing. Deterioration in anti‐stain property is also observed as ageing progresses. The deterioration in performance is mainly governed by the depletion in additives and generation of free fatty acids within the rolling oil bath. Proper maintenance of the bath ensures lesser defect formation.

Extrusion inhibits lipolytic enzymes in pearl millet (Pennisetum glaucum) flour

The present study was undertaken to evaluate the effect of extrusion technology on anti-nutritional factors and lipolytic enzymes in pearl millet. The effect of process parameters such as die temperature (140–160 °C), screw speed (150–190 rpm), and feed moisture content (24–30%) was evaluated using response surface methodology. The extrudates so obtained were evaluated for their physico-chemical and functional properties. Optimized extrudate that showed maximum inhibition of anti-nutritional factors and lipolytic enzymes was evaluated for extent of starch gelatinization by differential scanning calorimetry, structural properties by FTIR, morphology by scanning electron microscopy, and crystallinity by X-ray diffractometry. Extrusion at 140 °C/150 rpm/30% moisture content could decrease trypsin inhibitors (∼100%), phytic acid (up to 89%) and condensed tannin (up to 85%), and inhibited lipase and lipoxygenase activities by 79.2 and 77.9%, respectively. The results so obtained are promising for extending the shelf life of pearl millet flour and utilizing it in food premixes. Industrial relevance textThe presence of lipase and lipoxygenase enzymes in pearl millet limits its shelf life due to generation of free fatty acids which results in bitter taste and off flavour. The presence of anti-nutrients such as phytic acid, trypsin inhibitor and condensed tannins restricts its digestibility, and poses challenges to its commercial as well as domestic use. Extrusion has attracted attention in millet processing due to its feasibility for implementation in the food industry without major additional costs. The extrusion processing parameters, mainly temperature, screw speed and moisture content 140 °C/150 rpm/30% decreased trypsin inhibitors (∼100%), phytic acid (up to 89%) and condensed tannin (up to 85%), and inhibited lipase and lipoxygenase activities by 79.2 and 77.9%, respectively. These results on inhibition of lipolytic enzymes through extrusion could help in extending the shelf life of pearl millet flour. It is anticipated that extruded pearl millet flour could form a base for premixes based thereon.

Mitophagy Responds to the Environmental Temperature and Regulates Mitochondrial Mass in Adipose Tissues.

There are at least two types of adipose tissues in the body, defined as brown adipose tissues (BATs) and white adipose tissues (WATs). These tissues comprise brown and white adipocytes, respectively. The adipocytes are commonly endowed with mitochondria, but they have diverse characteristics and roles. Brown adipocytes have abundant mitochondria that contribute to the β-oxidation of fatty acids to produce chemical energy and the production of heat via uncoupling of the mitochondrial membrane potential from ATP synthesis. Alternatively, white adipocytes have fewer mitochondria that contribute to the generation of free fatty acids via lipogenesis by providing key intermediates. Besides the described types of adipocytes, brown-like adipocytes, termed beige adipocytes, are developed in WAT depots during cold exposure. Beige adipocytes also contribute to thermogenesis. Notably, beige adipocytes may transform into white-like adipocytes after the withdrawal of cold exposure. This process is marked by the elimination of mitochondria through the activation of mitochondria autophagy (mitophagy). This review aims to describe the mitophagy that occurs during the beige-to-white transition and discuss recent insights into the molecular mechanisms of this transformation. Additionally, we describe the mitophagy monitoring strategy in adipose tissues using three independent reporter systems and discuss the availabilities and limitations of the method.

Free Fatty Acids and Cocoa Butter Quality Traits: Causes and Impact on Consumers’ Health

Cocoa butter (CB) technological quality and financial value depend widely on the free fatty acids (FFA) content. Cocoa butter has to contain less than 1.75% free fatty acids (FFA, based on oleic acid) to be in compliance with the EU directive 2000/36/EC (2000) and needs to be free from off-flavours and rancidity from a sensory (taste, odour, colour) and technological point of view. Free fatty acids are carboxylic acids, generated from triglycerides via the hydrolysis of their ester bounds by enzymatic and/or chemical reactions. The present work reviews free fatty acids formation mechanisms in cocoa beans, the free fatty acids levels assay as well as possible reduction methods. Furthermore, the impact of high free fatty acids content on the technological and chemical qualities and on the health of consumer of cocoa derived products were described. The results highlighted that the free fatty acids formation in cocoa beans was ascribed to the endogenous and exogenous lipases activities. Excreted exogenous lipases by contaminated molds during poor post-harvest processing are most active for free fatty acids generation in cocoa beans. In addition, the germination, poor storage conditions such as high water activity and moisture content provoke high free fatty acids content in cocoa butter. Although alkalization, deodorization and other refining treatments are efficient methods for reduction of free fatty acids content, chocolate manufacturers recorded high losses in cocoa butter. It is important to eliminate the free fatty acids content of cocoa butter because excessive consumption of high- free fatty acids cocoa product induces pathologies.

Characterization of recombinant cutinase from Thermobifida cellulosilytica and its application in tomato cutin degradation

Cutinases are desirable biorecycling agents for big molecules because of their great efficiency in generating monomer under mild reaction conditions. In this study, the biochemical characterizations of a thermostable cutinase from Thermobifida cellulosilytica for tomato cutin degradation are presented. The cutinase gene was chosen from the sequence database. The gene was synthesized, cloned, and successfully expressed in the Escherichia coli (E. coli) system. SDS-PAGE analysis revealed that the cutinase had a molecular weight of approximately 29kDa. The recombinant cutinase showed highest activity at an optimum pH of 9.0. The result also showed thermal stability up to 60 °C. The activity of the recombinant cutinase was enhanced by 1 mM NaCl, 5 mM NaCl and 1 mM CaCl2; however, slightly inhibited by 5 mM CaCl2. Cutin from tomato peel was efficiently degraded into free fatty acid monomers. The bonding features between the deteriorated and polymerized cutin were clearly visible in the fourier transformed infrared spectroscopy study. These findings open the possibilities of using cutinases for the generation of free fatty acids from tomato peel. It could be a potential raw material for other industrial applications.

Therapeutic strategy targeting host lipolysis limits infection by SARS-CoV-2 and influenza A virus

The biosynthesis of host lipids and/or lipid droplets (LDs) has been studied extensively as a putative therapeutic target in diverse viral infections. However, directly targeting the LD lipolytic catabolism in virus-infected cells has not been widely investigated. Here, we show the linkage of the LD-associated lipase activation to the breakdown of LDs for the generation of free fatty acids (FFAs) at the late stage of diverse RNA viral infections, which represents a broad-spectrum antiviral target. Dysfunction of membrane transporter systems due to virus-induced cell injury results in intracellular malnutrition at the late stage of infection, thereby making the virus more dependent on the FFAs generated from LD storage for viral morphogenesis and as a source of energy. The replication of SARS-CoV-2 and influenza A virus (IAV), which is suppressed by the treatment with LD-associated lipases inhibitors, is rescued by supplementation with FFAs. The administration of lipase inhibitors, either individually or in a combination with virus-targeting drugs, protects mice from lethal IAV infection and mitigates severe lung lesions in SARS-CoV-2-infected hamsters. Moreover, the lipase inhibitors significantly reduce proinflammatory cytokine levels in the lungs of SARS-CoV-2- and IAV-challenged animals, a cause of a cytokine storm important for the critical infection or mortality of COVID-19 and IAV patients. In conclusion, the results reveal that lipase-mediated intracellular LD lipolysis is commonly exploited to facilitate RNA virus replication and furthermore suggest that pharmacological inhibitors of LD-associated lipases could be used to curb current COVID-19- and future pandemic outbreaks of potentially troublesome RNA virus infection in humans.

The role of oil concentration on the rheological properties, microstructure, and in vitro digestion of cellulose ether emulsions

The effect of oil concentration (from 5 to 47%) and type of cellulose ether on the rheological properties (flow and linear viscoelasticity), microstructure and oil digestion in o/w cellulose ether emulsions were investigated in the study. Three types of cellulose ethers were used: a hydroxypropyl methylcellulose (HPMC) and two methylcelluloses (MC) with different degrees of methoxyl content. All the emulsions showed shear thinning behaviour. The increase in oil concentration increase the emulsion's viscosity, the viscoelastic moduli G′ and G″, and decreases the loss tangent. The greatest viscosity and viscoelasticity was in the MC with the highest methoxyl content. Oil digestibility was determined by a titration method during in vitro digestion. Compared to a whey protein emulsion (control), the cellulose ether emulsions required a lower NaOH, which indicates lower free fatty acid generation and lower fat digestion. In the cellulose ether emulsions, this decrease in oil digestion was found at all the oil concentrations. A difference in oil digestion kinetics was found between the cellulose ether emulsion (linear) and the control (logarithmic), which was associated to a saturation in the digestive system in the whey protein emulsion. The microstructure after in vitro digestion showed practically no fat globules in the whey protein emulsion, whereas fat globules were observed in the cellulose ether emulsions, which confirms the highest oil digestion in the control emulsion. Cellulose ether emulsions with a wide variety of rheological properties can be obtained by varying cellulose type and oil concentration, with the barrier against fat digestion effective at low and high oil concentrations. • The effect of oil contentin rheology, microstructure and digestion of emulsions were studied. • Viscosity and viscoelasticity increased with oil concentration. • Cellulose ethers showed lower digestibility than a whey protein control. • Different oil digestion kinetics was found among cellulose ether and whey protein control. • Saturation occurs in the whey protein emulsion at higher oil concentration.

Lysosomal Acid Lipase a (LIPA) Modulates Leukemia Stem Cell (LSC) Response to Venetoclax/TKI Combination Therapy in Blast Phase Chronic Myeloid Leukemia

Chronic myeloid leukemia (CML) is a heterogeneous disease, initiated by reciprocal translocation of chromosome 9 and 22, resulting in the generation of a BCR-ABL fusion protein and constitutive activation of the ABL kinase. ABL tyrosine kinase inhibitors (TKIs) have been very successful in suppressing CML disease. However, TKIs may not eliminate leukemia stem cells (LSCs), as evidenced by the frequent re-emergence of the disease upon TKI discontinuation. Moreover, blast phase CML (bpCML) remains a formidable challenge in disease management. Recent clinical evidence suggests that the BCL2 inhibitor venetoclax (Ven) in combination with ABL-targeting tyrosine kinase inhibitors (TKI) can eradicate bpCML LSCs. However, the exact mechanism by which this combination may targets LSCs is not known. In this report, we confirm the efficacy and LSC-targeting capacity of Ven/TKI combination in preclinical models of bpCML and we further identify that inhibition of free fatty acid (FFA) mobilization pathways may provide enhanced efficacy against LSCs.To establish the efficacy of Ven/TKI combination, we treated bpCML samples with Ven+Dasatinib (Das) combination for 24h, this resulted in a significant decrease in the viability of bulk and primitive populations (CD34+, CD38+). Patient-derived xenografts of bpCML samples in NSGS-mice, were treated with Ven/Das as well as single agents. The result showed a significant decrease in leukemia burden in the combination treated group, compared to either drug alone, albeit, some resistant cells survived in the combo treated group. Furthermore, using a syngeneic mouse model of bpCML, co-expressing Bcr-Abl and Nup98-HOXA9 translocations, the mouse leukemic cells treated with Ven/Dasatinib combination demonstrated a significant loss of viability of the bulk as well as phenotypically defined LSCs (Lin-/Sca1+). Treatment of leukemic mice with Ven/Das had a significant survival benefit and remained disease free at 80 days post treatment. We also showed significant survival benefits of Ven/ponatinib in NSGS-mice harboring syngeneic bpCML cells with the T315I gatekeeper mutation. Treatment of normal mice with Ven/Das combo did not affect the colony forming ability of LSK cells from the bone marrow, indicating a leukemia-specific response. Based on these results, we conclude that Ven/TKI combination effects were due to direct targeting of the LSC population.To investigate the potential mechanism of Ven/TKI activity in LSC targeting, we performed gene expression studies using RNA-seq based methods after short term treatment. Our findings indicated that the LSC population from Ven/TKI-treated mice showed enrichment of a gene signature associated with lysosome biology. Pre-treatment of mouse leukemia cells with bafilomycin, an inhibitor of lysosome function, resulted in increased sensitivity to Ven/TKI combo. Intriguingly, we also found significant induction of lysosomal acid lipase (LIPA), an enzyme involved in the generation of free fatty acids for energy needs.Metabolomic analysis of LSCs isolated after short term treatment with Ven/TKI, showed that a number of fatty acids were up-regulated in the Ven/Das treated group compared to control. Knocking down Lipa using CRISPR technology resulted in increased sensitivity to Ven/TKI combination, whereas overexpression of Lipa resulted in decreased sensitivity to the Ven/TKI combination, implicating Lipa upregulation and a resultant increase in free fatty acids as a protective response to Ven/TKI treatment. Furthermore, knocking down CPT1A, an important free fatty acid mitochondrial transporter, resulted in increased sensitivity to Ven/TKI combination both in mouse and primary human leukemic cells, leading to the hypothesis that activation of fatty acid processing through enhanced Lipa activity may represent a compensatory response to venetoclax based therapies in bpCML.In summary, we demonstrate the preclinical efficacy of Ven/TKI combination therapies for targeting of bpCML LSCs. Furthermore, our data suggest that blocking upregulation of free fatty acids through mechanisms such as inhibition of LIPA activity, might synergize with Ven/TKI combinations to eradicate LSCs, allowing for more durable response. Our findings provide a therapeutic rationale for blocking pathways involved in free fatty acids generation, as a potential strategy for increasing remission duration. DisclosuresPollyea: Amgen: Consultancy; Janssen: Consultancy; Genentech: Consultancy; AbbVie: Consultancy, Research Funding; Syndax: Consultancy; Daiichi Sankyo: Consultancy; Takeda: Consultancy; Pfizer: Consultancy; Celgene/BMS: Consultancy; Agios: Consultancy; Karyopharm: Consultancy; Novartis: Consultancy; Glycomimetics: Other. Smith: Syros: Research Funding; Kura: Research Funding; Argenx: Research Funding.

Development of CRISPR-Cas9 knock-in tools for free fatty acid production using the fast-growing cyanobacterial strain Synechococcus elongatus UTEX 2973

Synechococcus elongatus UTEX 2973 has one of the fastest measured doubling time of cyanobacteria making it an important candidate for metabolic engineering. Traditional genetic engineering methods, which rely on homologous recombination, however, are inefficient, labor-intensive, and time-consuming due to the oligoploidy or polyploidy nature of cyanobacteria and the reliance on unique antibiotic resistance markers. CRISPR-Cas9 has emerged as an effective and versatile editing platform in a wide variety of organisms, but its application for cyanobacterial engineering is limited by the inherent toxicity of Cas9 resulting in poor transformation efficiencies. Here, we demonstrated that a single-plasmid CRISPR-Cas9 system, pCRISPOmyces-2, can effectively knock-in a truncated thioesterase gene from Escherichia coli to generate free fatty acid (FFA) producing mutants of Syn2973. To do so, three parameters were evaluated on the effect of generating recipient colonies after conjugation with pCRISPOmyces-2-based plasmids: 1) a modified conjugation protocol termed streaked conjugation, 2) the deletion of the gene encoding RecJ exonuclease, and 3) single guide RNA (sgRNA) sequence. With the use of the streaked conjugation protocol and a ΔrecJ mutant strain of Syn2973, the conjugation efficiency for the pCRISPomyces-2 plasmid could be improved by 750-fold over the wildtype (WT) for a conjugation efficiency of 2.0 × 10−6 transconjugants/recipient cell. While deletion of the RecJ exonuclease alone increased the conjugation efficiency by 150-fold over the WT, FFA generation was impaired in FFA-producing mutants with the ΔrecJ background, and the large number of poor FFA-producing isolates indicated the potential increase in spontaneous mutation rates. The sgRNA sequence was found to be critical in achieving the desired CRISPR-Cas9-mediated knock-in mutation as the sgRNA impacts conjugation efficiency, likelihood of homogenous recombinants, and free fatty acid production in engineered strains.

Organelle homeostasis principles: How organelle quality control and inter-organelle crosstalk promote cell survival.

To survive, cells sense their surroundings and adapt to enable homeostasis. Studies dissecting this process reveal organizational principles, including quality-control pathways, changes to organelle shape, and inter-organelle communication, that facilitate metabolic or developmental remodeling. In this issue, several reviews discuss these organelle homeostasis principles and how they are altered in disease.

Dissolution of Polysorbate 20 Degradation Related Free Fatty Acid Particles in Intravenous Bag Solutions.

Degradation of Polysorbate 20 (PS20), a commonly used surfactant in drug product (DP) formulations, is a phenomenon of increasing concern to the biopharmaceutical industry. One of the most prevalent modes of PS20 degradation is enzymatic hydrolysis resulting from co-purified hydrolases that make their way into biologic DP formulations at trace levels. Enzymatic PS20 degradation results in generation of free fatty acids (FFAs) that have limited solubility in aqueous formulations and can form visible and/or sub-visible particles which is undesirable for parenteral DP stability and administration. Many therapeutic monoclonal antibodies are administered intravenously after first diluting the DP into an infusion solution (e.g., 0.9% normal saline, 0.45% half normal saline or 5% dextrose). The purpose of this work is to understand if FFA particles in the DP dissolve in intravenous solutions prior to administration. Our assessment indicates that visible and/or sub-visible particles that contain high levels of lauric, myristic and palmitic acids dissolve immediately upon dilution (at or exceeding two fold) regardless of the intravenous bag or solution type. Therefore, the risk is low of visible and/or sub-visible particles, comprised of FFAs in biopharmaceutical DPs, being intravenously administered to a patient.

Inhibition of Free Fatty Acids generation in Crude Palm Oil during storage by using UV-C Light treatment

During the lengthy storage of crude palm oil (CPO), free fatty acid (FFA) concentration generated in the oil tends to increase which will affect the quality of CPO as the result of lipase enzymatic degradation of triglycerides. Currently, the conventional thermal processes in CPO storage tanks still applied to reduce the FFA formation. However, the thermal method is not very effective in reducing FFA for prolonged heat exposed due to deteriorate the CPO quality and high energy consuming. The alternative UV-C light technique gives some advantages compare with thermal treatment i.e less energy consumption, simple method, cheaper investment and low-cost operation. This study is aimed to evaluate the effects of UV-C light on inhibiting FFA generation in CPO during storage. The evaluation of UV-C light effect on the inhibition of FFA generation was conducted by irradiating CPO samples with various UV-C light exposure time. The FFA level of CPO samples was analyzed by using sodium hydroxide solution before and after treatment. The results show that UV-C light has the ability to deactivate lipase enzyme and consequently inhibit FFA generation in CPO.

Photobiomodulation therapy decreases free fatty acid generation and release in adipocytes to ameliorate insulin resistance in type 2 diabetes

Excessive circulating free fatty acids (FFA) cause insulin resistance in peripheral tissues by inhibiting the proximal insulin signaling pathway. White adipose tissue (WAT) is a primary source of FFA generation and release through triglyceride (TG) hydrolysis. Thus, reducing excessive lipolysis in adipocytes ameliorates whole-body insulin resistance in type 2 diabetes. Here, we found that a noninvasive photobiomodulation therapy (PBMT), decreased FFA generation and release in WATs from high-fat diet (HFD)-fed mice and diabetic db/db mice. Meanwhile, plasma FFA and TG levels were reduced in two mouse models after PBMT. PBMT promoted mitochondrial reactive oxygen species (ROS) generation, which inhibited phosphatase and tensin homologue (PTEN) and promoted protein kinase B (AKT) activation. Photoactivation of AKT inhibited the transcriptional activity of Forkhead box transcription factor O1 (FoxO1), reducing expression of lipolytic enzymes and FFA generation and release. Eliminating ROS elimination or inhibiting AKT blocked the effects of the laser therapy in vivo and in vitro. Taken together, PBMT suppresses FFA generation and release in insulin-resistant adipocytes, contributing to improvement of insulin resistance in mouse models of type 2 diabetes.

Deacetylation of LAMP1 drives lipophagy-dependent generation of free fatty acids by Abrus agglutinin to promote senescence in prostate cancer.

Therapy-induced senescence in cancer cells is an irreversible antiproliferative state, which inhibits tumor growth and is therefore a potent anti-neoplastic mechanism. In this study, low doses of Abrus agglutinin (AGG)-induced senescence through autophagy in prostate carcinoma cells (PC3) and inhibited proliferation. The inhibition of autophagy with 3-methyl adenine reversed AGG-induced senescence, thus confirming that AGG-triggered senescence required autophagy. AGG treatment also led to lipophagy-mediated accumulation of free fatty acids (FFAs), with a concomitant decrease in the number of lipid droplets. Lalistat, a lysosomal acid lipase inhibitor, abrogated AGG-induced lipophagy and senescence in PC3 cells, indicating that lipophagy is essential for AGG-induced senescence. The accumulation of FFAs increased reactive oxygen species generation, a known facilitator of senescence, which was also reduced in the presence of lalistat. Furthermore, AGG upregulated silent mating type information regulator 2 homolog 1 (SIRT1), while the presence of sirtinol reduced autophagy flux and the senescent phenotype in the AGG-treated cells. Mechanistically, AGG-induced cytoplasmic SIRT1 deacetylated a Lys residue on the cytoplasmic domain of lysosome-associated membrane protein 1 (LAMP1), an autolysosomal protein, resulting in lipophagy and senescence. Taken together, our findings demonstrate a novel SIRT1/LAMP1/lipophagy axis mediating AGG-induced senescence in prostate cancer cells.

Effects of triacylglycerol on the structural remodeling of human plasma very low- and low-density lipoproteins

Very low-density lipoprotein (VLDL) is the main plasma carrier of triacylglycerol that is elevated in pathological conditions such as diabetes, metabolic syndrome, obesity and dyslipidemia. How variations in triacylglycerol levels influence structural stability and remodeling of VLDL and its metabolic product, low-density lipoproteins (LDL), is unknown. We applied a biochemical and biophysical approach using lipoprotein remodeling by lipoprotein lipase and cholesterol ester transfer protein, along with thermal denaturation that mimics key aspects of lipoprotein remodeling in vivo. The results revealed that increasing the triacylglycerol content in VLDL promotes changes in the lipoprotein size and release of the exchangeable apolipoproteins. Similarly, increased triacylglycerol content in LDL promotes lipoprotein remodeling and fusion. These effects were observed in single-donor lipoproteins from healthy subjects enriched in exogenous triolein, in single-donor lipoproteins from healthy subjects with naturally occurring differences in endogenous triacylglycerol, and in LDL and VLDL from pooled plasma of diabetic and normolipidemic patients. Consequently, triacylglycerol-induced destabilization is a general property of plasma lipoproteins. This destabilization reflects a direct effect of triacylglycerol on lipoproteins. Moreover, we show that TG can act indirectly by increasing lipoprotein susceptibility to oxidation and lipolysis and thereby promoting the generation of free fatty acids that augment fusion. These in vitro findings are relevant to lipoprotein remodeling and fusion in vivo. In fact, fusion of LDL and VLDL enhances their retention in the arterial wall and, according to the response-to-retention hypothesis, triggers atherosclerosis. Therefore, enhanced fusion of triacylglycerol-rich lipoproteins suggests a new causative link between elevated plasma triacylglycerol and atherosclerosis.

Free Fatty‐Acid Generation and Lipid Oxidation during Dry‐Grind Corn Ethanol Fermentation

AbstractThe formation of free fatty acid (FFA) is an undesirable change during dry‐grind corn ethanol fermentation because it negatively affects biodiesel transformation. The primary objective of this work was to determine where in the process FFA is generated using laboratory‐scale simulation experiments. TLC and GC were used to quantify FFA in the extracted total lipids. Values obtained from FFA determination by titration were also compared with those obtained from TLC‐GC. Results indicate that FFA generation is due to an incremental increase at each step in the process, particularly at the early slurrying and liquefaction stage, and also likely during the continuous backset. Furthermore, laboratory‐based fermentations indicate that the oxidation of linoleic acid in the FFA fraction and possibly in the oil increased the FFA level determined using the titration method. Industrial oil samples collected were shown to be highly oxidized and this led to an overestimation of FFA by 15–24% using the titration method compared to TLC‐GC due to the formation of a secondary oxidation product, acids. Such a discrepancy in FFA quantification and the level of lipid oxidation have not been seen in the literature.

SGLT2 INHIBITOR-INDUCED EUGLYCEMIC DIABETIC KETOACIDOSIS

SESSION TITLE: Critical Care 1 SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/09/2018 01:15 PM - 02:15 PM INTRODUCTION: Diabetic Ketoacidosis (DKA) is a life-threatening complication of diabetes mellitus. While most cases of DKA present with hyperglycemia coupled with anion-gap metabolic acidosis and ketonemia, some cases, referred to as “Euglcyemic DKA”, may present with normal blood glucose levels. Sodium-glucose cotransporter 2 (SGLT-2) inhibitors are a class of oral hypoglycemic agents which target the SGLT-2 transporter in renal proximal convoluted tubules, preventing reabsorption of glucose from urine into the bloodstream. We present a patient of Type 2 Diabetes Mellitus (T2DM) who was on an SGLT-2 inhibitor and developed euglycemic ketoacidosis. CASE PRESENTATION: A 38 year old male with a past history of T2DM accompanied with neuropathy, peripheral vascular disease and hypertension, presented to the ED with a three day history of nausea and vomiting. His home medications included empagliflozin, metformin and insulin detemir. Our patient reported medication compliance and denied recent alcohol consumption. He was afebrile; BP 159/71 mmHg and pulse 118 BPM. On exam, patient appeared in mild distress with abdominal tenderness. Labs revealed an anion-gap of 24, blood glucose of 176 g/dL with a normal BUN, creatinine and lactic acid. Urinalysis revealed ketones and glycosuria. At this time, euglycemic DKA was highly suspected. He was admitted to the MICU and DKA protocol was initiated. He was administered normal saline, Dextrose 5% in water with IV insulin drip at 0.1U/kg/hr with concurrent potassium supplementation. After his anion gap closed within 24 hours, our patient was switched to a basal and pre-meal insulin regimen. DISCUSSION: Euglycemic DKA is characterized by normal to mildly elevated blood glucose levels and can be missed due to the absence of hyperglycemia that’s usually seen in DKA. SGLT-2 inhibitors lower blood glucose levels by increasing urinary glucose excretion, which reduces the stimulus for pancreatic β-cell insulin secretion. Insulin normally acts to inhibit hormone-sensitive lipase, thereby decreasing the generation of free-fatty acids that serve as a substrate for β-oxidation and ketogenesis. With SGLT-2 inhibitors, marked glycosuria and resultant decreased insulin secretion results in uninhibited lipolysis, increased β-oxidation and ketogenesis. As a result of decreased blood glucose levels, pancreatic α-cells are stimulated to increase glucagon secretion, further promoting lipolysis and ketogenesis. CONCLUSIONS: Management of SGLT-2 inhibitor euglycemic DKA follows the American Diabetes Association recommendations with focus on intravenous fluids, insulin and electrolyte management. However, initiation of dextrose in IV fluids is imperative considering the euglycemic nature of the pathogenesis. Upon stabilization and subsequent discharge, patients should discontinue SGLT-2 inhibitors and maintain adequate hydration going forward. Reference #1: LexiComp Online. 2016 Wolters Kluwer Clinical Drug Information Inc. July 29, 2016. Reference #2: Peters, Anne L, Buschur EO, Buse JB, Cohan P, Dinner JC, Hirsch IB. Euglycemic Diabetic Ketoacidosis: A Potential Complication of Treatment with Sodium-Glucose Cotransporter 2 Inhibition. Diabetes Care 2015; 38:1687-1693 DISCLOSURES: No relevant relationships by Ambreesh Chawla, source=Web Response no disclosure on file for Austin Healy; No relevant relationships by Minha Kim, source=Web Response no disclosure on file for Sunil Sapru

Relationship between cellulose chemical substitution, structure and fat digestion in o/w emulsions

The effect of cellulose ether chemical substitution on the reduction of fat digestion in an o/w emulsion was investigated. Emulsions containing 47% sunflower oil and water were prepared with two types of hydroxypropyl methylcellulose (HPMC) and two types of methyl cellulose (MC), with different hydroxypropyl and methoxyl content. The changes in the emulsion structure were evaluated after mouth, stomach and small intestine in vitro digestion by Confocal laser microscopy and by small amplitude oscillatory shear (viscoelastic properties). The total amount of fat present in the supernatant after digesta centrifugation, serving as an indicator of fat bioaccessibility, and the free fatty acids, serving as an indicator of fat digestion, were determined at the end of the digestion. A relationship was found between cellulose ether chemical substitution, initial structure, structural changes during digestion, fat bioaccessibility and fat digestion. All the cellulose ether emulsions showed a lower level of fat digestion in comparison with a whey protein emulsion, the cellulose ether containing the highest amount of methoxyl being the most effective. The rise in the methoxyl content increases the emulsion viscoelastic properties before and after digestion and reduces fat bioaccessibility and the generation of free fatty acids. The decrease in the fat digestibility of the cellulose ether emulsions was mainly associated with a physical effect, which limits the emulsification of appropriate fats by bile salts, and the subsequent lipase digestion effect.

Micro RNA-124a regulates lipolysis via adipose triglyceride lipase and comparative gene identification 58.

Lipolysis is the biochemical pathway responsible for the catabolism of cellular triacylglycerol (TG). Lipolytic TG breakdown is a central metabolic process leading to the generation of free fatty acids (FA) and glycerol, thereby regulating lipid, as well as energy homeostasis. The precise tuning of lipolysis is imperative to prevent lipotoxicity, obesity, diabetes and other related metabolic disorders. Here, we present our finding that miR-124a attenuates RNA and protein expression of the major TG hydrolase, adipose triglyceride lipase (ATGL/PNPLA2) and its co-activator comparative gene identification 58 (CGI-58/ABHD5). Ectopic expression of miR-124a in adipocytes leads to reduced lipolysis and increased cellular TG accumulation. This phenotype, however, can be rescued by overexpression of truncated Atgl lacking its 3'UTR, which harbors the identified miR-124a target site. In addition, we observe a strong negative correlation between miR-124a and Atgl expression in various murine tissues. Moreover, miR-124a regulates the expression of Atgl and Cgi-58 in murine white adipose tissue during fasting as well as the expression of Atgl in murine liver, during fasting and re-feeding. Together, these results point to an instrumental role of miR-124a in the regulation of TG catabolism. Therefore, we suggest that miR-124a may be involved in the regulation of several cellular and organismal metabolic parameters, including lipid storage and plasma FA concentration.