Synthetic Triglyceride Research Articles

Oral Administration of a Novel, Synthetic Ketogenic Compound Elevates Blood β-Hydroxybutyrate Levels in Mice in Both Fasted and Fed Conditions.

Elevating ketone levels with therapeutic nutritional ketosis can help to metabolically manage disease processes associated with epilepsy, diabetes, obesity, cancer, and neurodegenerative disease. Nutritional ketosis can be achieved with various dieting strategies such as the classical ketogenic diet, the modified Atkins diet, caloric restriction, periodic fasting, or the consumption of exogenous ketogenic supplements such as medium-chain triglycerides (MCTs). However, these various strategies can be unpleasant and difficult to follow, so that achieving and sustaining nutritional ketosis can be a major challenge. Thus, investigators continue to explore the science and applications of exogenous ketone supplementation as a means to further augment the therapeutic efficacy of this metabolic therapy. Here, we describe a structurally new synthetic triglyceride, glycerol tri-acetoacetate (Gly-3AcAc), that we prepared from glycerol and an acetoacetate precursor that produces hyperketonemia in the therapeutic range (2-3 mM) when administered to mice under both fasting and non-fasting conditions. Animal studies were undertaken to evaluate the potential effects of eliciting a ketogenic response systemically. Acute effects (24 h or less) were determined in male VM/Dk mice in both fasted and unfasted dietary states. Concentration levels of β-hydroxybutyrate in blood were elevated (βHB; 2-3 mM) under both conditions. Levels of glucose were reduced only in the fasted state. No detrimental side effects were observed. Pending further study, this novel compound could potentially add to the repertoire of methods for inducing therapeutic nutritional ketosis.

A fully bio‐based monomer derived from undecylenic acid, glycerol, and CO2 useful for the synthesis of polyhydroxyurethanes

AbstractUndecylenic acid, glycerol, and CO2 were used as building blocks for obtaining a fully bio‐based carbonated monomer, useful for polyurethanes. The functionality of the monomer was close to 3 cyclic carbonates/mol, located in terminal positions. In a first stage, a synthetic triglyceride was obtained with 99% selectivity by esterification of glycerol and undecylenic acid at 160°C. The triglyceride was then epoxidized using H2O2 and Amberlyst 15 or Amberlite IR‐120 acidic exchange resins at 57°C. The selectivity to epoxide was kept constant at 98% using Amberlite IR‐120. Terminal cyclic carbonates were then inserted through epoxide moieties under mild conditions by the chemical fixation of CO2 at 80°C and 6 MPa in 6 h. A complete conversion was obtained in 6 h reaction while the selectivity to carbonate groups was near to 99% during all the reaction time. An elastomeric polyhydroxyurethane was obtained by aminolysis of the carbonated monomer with ethylenediamine at 70°C, affording a Young's modulus of 22.6 MPa and Tg of −15.2°C. The material showed a good thermal stability below 240°C.

Long-term experience with triheptanoin in 12 Austrian patients with long-chain fatty acid oxidation disorders

BackgroundLong-chain fatty acid oxidation disorders (LC-FAOD) are a group of rare inborn errors of metabolism with autosomal recessive inheritance that may cause life-threatening events.Treatment with triheptanoin, a synthetic seven-carbon fatty acid triglyceride compound with an anaplerotic effect, seems beneficial, but clinical experience is limited. We report our long-term experience in an Austrian cohort of LC-FAOD patients.MethodsWe retrospectively assessed clinical outcome and total hospitalization days per year before and after start with triheptanoin by reviewing medical records of 12 Austrian LC-FAOD patientsResultsFor 12 Austrian LC-FAOD patients at three metabolic centers, triheptanoin was started shortly after birth in 3/12, and between 7.34 and 353.3 (median 44.5; mean 81.1) months of age in 9/12 patients. For 11 pediatric patients, mean duration of triheptanoin intake was 5.3 (median 3.9, range 1.2–15.7) years, 10/11 pediatric patients have an ongoing intake of triheptanoin. One patient quit therapy due to reported side effects. Total hospitalization days per year compared to before triheptanoin treatment decreased by 82.3% from 27.1 (range 11–65) days per year to 4.8 (range 0–13) days per year, and hospitalization days in the one year pre- compared to the one year post-triheptanoin decreased by 69.8% from 27.1 (range 4–75) days to 8.2 (range 0–25) days. All patients are in good clinical condition, show normal psychomotor development and no impairment in daily life activities.ConclusionIn this retrospective observational study in an Austrian LC-FAOD cohort, triheptanoin data show improvement in disease course. Triheptanoin appears to be a safe and beneficial treatment option in LC-FAOD. For further clarification, additional prospective randomized controlled trials are needed.

Triglyceride accumulation in macrophages upregulates paraoxonase 2 (PON2) expression via ROS‐mediated JNK/c‐Jun signaling pathway activation

The aim of this study was to analyze the effect and mechanism of action of macrophage triglyceride accumulation on cellular PON2 expression. Incubation of J774A.1 (murine macrophages) with VLDL (0-75 μg protein/mL) significantly and dose-dependently increased cellular triglyceride mass, and reactive oxygen species (ROS) formation, by up to 3.3- or 1.8-fold, respectively. PON2 expression (mRNA, protein, activity) in cells treated with VLDL (50 μg protein/mL) was higher by 2- to 3-fold, as compared with control cells. Similar effects were noted upon using THP-1 (human macrophages). Incubation of macrophages with synthetic triglyceride or triglyceride fraction from carotid lesion resulted in similar effects, as shown for VLDL. Upon using specific inhibitors of MEK1/2 (UO126, 10 μM), p38 (SB203580, 10 μM), or JNK (SP600125, 20 μM), we demonstrated that MEK, as well as JNK, but not p38, are involved in VLDL-induced macrophage PON2 upregulation. VLDL activated JNK (but not ERK), which resulted in c-Jun phosphorylation. This signaling pathway is probably activated by ROS, since the antioxidant reduced glutathione (GSH), significantly decreased VLDL-induced macrophage ROS formation, c-Jun phosphorylation and PON2 overexpression. We conclude that macrophage triglyceride accumulation upregulates PON2 expression via MEK/ JNK/c-Jun pathway, and these effects could be related, at least in part, to cellular triglycerides-induced ROS formation. ©

Paraoxonase 1 protects macrophages from atherogenicity of a specific triglyceride isolated from human carotid lesion

Human atherosclerotic lesions contain oxidized lipids that facilitate further oxidation of macrophages, LDLs, and oxidative stress (OS)-sensitive markers and inhibit the antiatherogenic enzyme paraoxonase 1 (PON1). Our aim was to isolate and identify the oxidizing agent in a human atherosclerotic lesion lipid extract (LLE) and to explore the mechanisms of oxidation and of PON1's effect on the oxidizing agent. Of the five main fractions separated from the LLE, only fraction 2 (F2) promoted macrophage reactive oxygen species (ROS) production via a mechanism requiring mitochondrial involvement, whereas the NADPH oxidase system was not involved. Incubation of F2 with PON1 abridged the former's peroxide value and reduced its capacity to oxidize OS markers. The active agent was a triglyceride composed of palmitic, oleic, and linoleic acids, with 0.3% of its linoleic moiety in oxidized form. Incubation of either F2 or an identical synthetic triglyceride with PON1 reduced their ability to oxidize macrophages, without affecting cellular accumulation of triglycerides. We conclude that macrophage ROS production by LLE occurs in the presence of a specific triglyceride and requires mitochondrial involvement. Lipid peroxide in the triglyceride can also facilitate lipid autoxidation. Both atherogenic pathways are suppressed by PON1, which acts as an antiatherogenic element.

Synthetic triglyceride containing an arachidonic acid branch (8A8) prevents lipopolysaccharide-induced liver injury

Aims In this study, we investigated the effect of synthetic triglyceride containing an arachidonic acid branch (8A8) on lipopolysaccharide (LPS)-induced production of tumor necrosis factor (TNF)-α and nitric oxide (NO) in macrophages, and LPS-induced liver injury in the rat. Main methods RAW264.7 macrophages were co-incubated with 8A8 and LPS (100 ng/ml), and TNF-α mRNA/protein levels, nuclear factor (NF)-κB DNA binding activity, expression of inducible-type NO synthase (NOS2), and NO 2 production were measured. Male Wistar rats were given a single intraperitoneal injection of 8A8 prior to an intravenous injection of LPS (5 mg/kg), and liver histology, apoptotic cell death, serum TNF-α levels, and hepatic TNF-α mRNA were then evaluated. Key findings LPS-induced increases in TNF-α production in RAW264.7 macrophages were blunted by 8A8 in a dose-dependent manner, with 40% inhibition at 100 ppm. Further, 8A8 dose-dependently prevented LPS-induced increases in TNF-α mRNA levels, as well as NF-κB DNA binding activities, in RAW264.7 macrophages. LPS-induction of NOS2 and NO 2 release from these cells was also decreased by 8A8 in a dose-dependent manner. In vivo, LPS-induced liver injury, including hepatocyte apoptosis, was largely prevented when 8A8 (100 µl/kg) was given 30 min prior to LPS. Indeed, 8A8 blunted increases in both serum TNF-α and hepatic TNF-α mRNA levels significantly. Significance LPS-induced liver injury was prevented by 8A8 most likely through the inhibition of TNF-α and NO production from hepatic macrophages, suggesting a potential usefulness of 8A8 as an immuno-modulating nutrient for prevention/treatment of endotoxin-related organ injuries including alcoholic liver disease and non-alcoholic steatohepatitis (NASH).

Esterification and transesterification on tungstated zirconia: Effect of calcination temperature

As part of ongoing efforts to investigate heterogeneous catalysts for biodiesel synthesis, the catalytic activity of the strong solid acid tungstated zirconia (WZ) was studied for the esterification of acetic acid (in both the gas and liquid phase) and the transesterification of triacetin (a synthetic triglyceride in the liquid phase) with methanol. Acetic acid and triacetin were used as model compounds for free fatty acids (FFAs) and triglycerides, respectively. Complex mixtures of FFAs and triglycerides are typical biodiesel precursors found in unrefined vegetable oils, animal fats, and waste greases. The effect of calcination temperature (400–900 °C) on the catalytic properties of WZ was investigated with the goal of determining the optimum pretreatment temperature and increasing the understanding of the nature of the active sites for esterification and transesterification. Catalyst characterization by powder X-ray diffraction, Raman spectroscopy, TGA, elemental analysis, and total BET surface area allowed us to correlate the changes in catalyst physicochemical properties with calcination temperature. Ion-exchange/titration and NH 3-TPD were used to characterize the number and strength of the acid sites. Esterification and transesterification rates (on a catalyst weight basis) increased with increasing surface WO x densities between 1.9 and 6.6 W-atoms nm −2 and then decreased for densities above 6.6 W-atoms nm −2. The growth of WO 3 crystalline species resulted in lower esterification and transesterification rates, consistent with a decrease in the number of active sites. For the catalyst that exhibited the optimum catalytic activity (calcined at 800 °C), selective poisoning of the potential catalytic centers revealed that Brønsted sites play the major role in carrying out these reactions.

High-yield purification of an organic solvent-tolerant lipase from Pseudomonas sp. strain S5

An organic solvent-tolerant S5 lipase was purified by affinity chromatography and anion exchange chromatography. The molecular mass of the lipase was estimated to be 60 kDa with 387 purification fold. The optimal temperature and pH were 45 °C and 9.0, respectively. The purified lipase was stable at 45 °C and pH 6–9. It exhibited the highest stability in the presence of various organic solvents such as n-dodecane, 1-pentanol, and toluene. Ca 2+ and Mg 2+ stimulated lipase activity, whereas EDTA had no effect on its activity. The S5 lipase exhibited the highest activity in the presence of palm oil as a natural oil and triolein as a synthetic triglyceride. It showed random positional specificity on the thin-layer chromatography.

Randomised controlled trial of a synthetic triglyceride milk formula for preterm infants

AIMSTo test whether use of infant formula containing synthetic structured triglycerides results in: (i) increased palmitate absorption; (ii) increased total fat absorption; (iii) reduction in calcium soap formation in the...

Biodegradation of sucrose poly fatty acid esters in soils

Sucrose polyesters (SPEs) were applied to soil at rates equivalent to 1062 to 1293 kg per hectare and incubated over periods of 100 to 403 days at 20 ± 2°C in darkness and at a soil moisture of 40 % of the maximum water holding capacity. All applied forms of SPEs were aerobically biodegraded to some degree in both American and German soil. However, the mineralization rates varied considerably and were dependent on both SPE and soil type. For example, sucrose octaoleate underwent slow and limited mineralization in the German soils Speyer and Borstel as well as in the American soil Madera, reaching only 6.9 – 18.4 % mineralisation after over 400 days incubation. The same material in the American soils Hollande, Thermal and Uvalde as well as in the German soil Speicherkoog, reached 35–52 % after the same incubation period. Of the SPEs most realistic for use in food products, the more liquid (i.e. with the least saturated fatty acids) underwent the most rapid and extensive mineralization. However, the mineralization rates for these materials were distinctly lower than the corresponding ones for sucrose octaoleate. In all cases the extent of mineralization of the SPEs in soil was significantly lower than that of a control fat (synthetic triglyceride mixture HB307), which typically underwent over 50 % mineralization in 60 days. As field conditions would be considerably different to those in the laboratory (due to the presence of microbially acclimatised sewage sludge, fluctuations in soil temperature and moisture, and contamination by ecotoxic pollutants) it is difficult to predict accurately, on the basis of laboratory results, the likely rate of mineralization of SPEs in the field. However, this study does suggest that the more solid the SPE, the more likely it is to persist, and possibly accumulate, following application to soil.

Peptide Targeting and Delivery across the Blood−Brain Barrier Utilizing Synthetic Triglyceride Esters: Design, Synthesis, and Bioactivity

As an approach to the development of therapeutically useful peptide pharmaceuticals that can penetrate the blood-brain barrier, we have designed and demonstrated the application of a carrier-targeting system. We have developed a prodrug design strategy that is designed to utilize membrane-bound enzymes whereby release of a bioactive peptide from a highly lipophilic triglyceride peptide-carrier is achieved in situ, thus attaining high localized concentrations of the bioactive peptide. Following localization of such a system, normal peptidase and lipase action is utilized to release the active peptide (deltorphin II) intact and in high concentration. At present, the exact mechanisms are unclear, but the observed results in which analgesia is observed following peripheral administration suggest that the active peptide is able to cross the blood-brain barrier and sustain prolonged periods of analgesia as determined by antinociception tests by release of the bioactive peptide. In vitro tests of binding and bioactivity by the peptide conjugate show essentially no potency in either target or control analogues, but potent antinociceptive effects are observed following peripheral administration.

Solubilities of methyl oleate, oleic acid, oleyl glycerols, and oleyl glycerol mixtures in supercritical carbon dioxide

Solubility isotherms for oleic acid and methyl oleate as well as mono‐, di‐, and trioleylglycerol (MO, DO, and TO) in supercritical fluid CO2 at 50 and 60°C are reported. Partition coefficients for quaternary (MO‐DO‐TO‐CO2) mixtures were obtained at 60°C at pressures ranging from 172 to 309 bar. Data indicate that diolein, and especially monoolein, exhibit positive deviation from ideal behavior, possibly due to intermolecular hydrogen bonding. Supercritical fluid CO2 appears to be a good media for removal of mono‐ and diacylglycerol by‐products from synthetic triglyceride reaction mixtures at moderate temperatures.

Screening of methylalkylketone-accumulating fungi from type culture strains

Fungal strains having the ability to accumulate methylalkylketones (MAKs) in culture medium containing tricaprin (synthetic triglyceride) or palm-kernel oil (natural triglycerides) were selected from type culture strains. Twenty two strains which were high accumulators were selected and concentrated taxonomically into the filamentous fungi of Deuteromycotina and Ascomycotina. The selected strains were divided into the following two types in terms of their MAK formation characteristics. The first type shows a high accumulation of methylheptylketone from tricaprin but a low accumulation of MAKs from palm-kernel oil, and the second type shows a high accumulation of MAKs from both tricaprin and palm-kernel oil. Fusarium, Trichoderma, and their related genera are grouped into the first type, and Penicillium, Aspergillus, Cladosporium, and their related genera are in the second type. The molecular sizes of the MAKs accumulated were short and middle carbon-lengths; carbon numbers 5–13. Specificity in the bioconversion of fatty acids to MAKs is as follows: one-carbon-atom-shorter MAK molecules (carbon number n-1) from fatty acids (carbon number n), constituents of triglycerides, are exclusively formed. However, some strains formed unknown product(s) other than MAKs. During time course experiments for MAK accumulation by P. decumbens IFO 7091, the degradation of accumulated MAK was discovered.

The effect of adsorbed lysozyme on interaction forces and coalescence of triglyceride droplets in aqueous salt solutions

We have used optical reflectance to measure the thickness of the draining film between droplets of a synthetic triglyceride (MCT810) brought together in aqueous solutions containing lysozyme (10 −3% w/w) and sodium chloride at 10 −1 to 10 −5 M. Drainage was essentially complete after ca. 30 s, the draining film then being close to plane parallel with a thickness in agreement with that calculated from a balance of electrostatic repulsive forces and capillary and van der Waals attractive forces, except at the highest salt concentration (10 −1 M) examined. Thicknesses ranged from 30 to 145 nm. The aqueous film collapsed after a time ranging from a few seconds to several hours, producing droplet coalescence. The median time to coalescence and the interquartile range increased with increasing film thickness. These data are not consistent with the concept of a “critical thickness” for the collapse of protein-stabilized films. The implications of the results for the use of proteins as emulsion stabilizers are discussed.

Biosynthesis of Flavor Compounds by Microorganisms 6. Odorous Constituents of Polyporus durus (Basidiomycetes)

Abstract The neutral volatile constituents produced by shake flask cultured mycelium of Polyporus durus comprise aliphatic and aromatic alcohols, lactones and various carbonyl compounds, and sesquiterpenoids. The occurrence of five 2,3-unsaturated 4-olides (γ-lactones), some of which were identified for the first time in nature, is characteristic of the fungus. The presence of a synthetic triglyceride in the nutrient medium strongly favors the formation of lactones and other volatile flavor compounds.

Determination of Triglyceride Composition by TLC·FID Method

A TLC-FID method to determine four glyceride types (S3, S2U, SU2, and U3) of fats was developed. Dipalmito-olein, palmito-diolein and triolein were quantitatively oxidised to the corresponding azelaoglycerides with KMnO4, but not tripalmitin. These azelaoglycerides and squalane added as an internal standard were separated on silica-gel TLC and determined with FID. Very good agreement between the determined and calculated compositions was obtained for some synthetic triglyceride mixtures with less polyenoic acid, but not for those with much polyenoic acid. The glyceride type composition of some natural oils and fats with less polyenoic and hydrogenated fats was determined by this method.

Relative bioactivity of alpha- and gamma-tocopherol calculated from respiration parameters in rat liver mitochondria.

In experiments with male wistar rats the influence of dl-alpha-tocopherol as well as dl-gamma-tocopherol on both the respiration of liver mitochondria and membrane lipid peroxidation has been investigated. For a test period of 8 weeks the animals were fed isoenergetic diets containing either no vitamin E or 46 mg d-alpha-tocopherol equivalents/kg diet as dl-alpha-tocopherol (60 ppm) or dl-gamma-tocopherol (480 ppm). The diets contained 6% of a synthetic triglyceride mixture rich in polyunsaturated fatty acids (about 60%). The measurements of the P/O ratios and corresponding respiratory control index (RCI) values for several substrates (alpha-ketoglutarate, malate/glutamate, succinate) indicated that under vitamin E-deficient conditions the mitochondria showed an increased respiratory intensity accompanied with an elevated lipid peroxidation. The oxidative phosphorylation itself was not affected. These deficiency symptoms could be normalized by the applied amounts of both tocopherols. In this respect dl-gamma-tocopherol showed a more distinct bioactivity than previously proposed. Based on the investigated parameters we calculated for dl-gamma-tocopherol an average bioactivity of 28% compared to that of dl-alpha-tocopherol.

Plasma fat metabolites and hunger

In order to test the hypothesis that the fat metabolites are the blood-borne signals which suppress hunger during recovery from reversible obesity, experiments were designed to manipulate plasma fat metabolite levels directly. In order to elevate plasma glycerol levels, glycerol was infused intravenously into relatively unrestrained rats for 36 hours; this treatment greatly increased plasma glycerol levels but reduced voluntary food intake only slightly. Similar results were obtained when glycerol was mixed with powdered rat food. These results suggest that glycerol is not the “lipostatic hormone” although it may contribute to regulation. Similar experiments with a synthetic precursor of the ketone bodies (1,3 butanediol), suggest that the ketone bodies contribute to the decrease in food intake after reversible obesity, but cannot be a complete explanation. Dietary fat consumption raised plasma free fatty acid (FFA) levels to the range seen during recovery from reversible obesity, suggesting that plasma FFAs may be a blood-borne signal of fat utilization in both cases. Intralipid, a synthetic triglyceride emulsion designed for intravenous administration, also increased plasma FFA levels but suppressed food intake by less than predicted. However, Intralipid may tend to cause spuriously high plasma FFA readings for reasons which are discussed. These results suggest that plasma fat metabolites, especially FFAs, may be blood-borne signals which contribute to the voluntary dieting after reversible obesity.

Differing uptake of emulsion triglyceride by the fed and fasted rat liver.

The recycling perfusion of a fasted rat liver with an apoprotein E-enriched synthetic triglyceride emulsion revealed a significantly greater hepatic uptake of both the apoprotein and the triglyceride than did the liver of a chow-fed animal. This greater hepatic triglyceride uptake by the perfused fasted liver in comparison to the fed was also noted for emulsions containing no added apoprotein or supplemented with both the E and CIII-1 proteins. However, no difference in the uptake of the triglyceride emulsion was seen for the fed and fasted livers when evaluated by a nonrecycling single pass perfusion. The isolated hepatocyte plasma membranes from fasted rats failed to demonstrate enhanced binding of apoprotein or lipid when compared to those from fed animals. If the residual E loaded triglyceride emulsion was recovered from the recycling perfusates of fed and fasted livers and evaluated in a non-recycling single-pass system, the emulsion from the fasted perfusion was cleared as facilely as previously, whereas that from the fed was less actively cleared. The emulsions retrieved from the perfusion of the fed liver contained significantly more protein than did the fasted; in particular apo C. This apparent alteration of emulsion apoproteins by the fed liver possibly results in a less active hepatic retrieval and may be important in downregulating the entry of lipoprotein triglyceride in the postabsorptive liver.

Gastric ulceration and the concentration of salicylate in plasma in rats after administration of 14C-labelled aspirin and its synthetic triglyceride, 1,3-dipalmitoyl-2(2'-acetoxy-[14C]carboxylbenzoyl) glycerol.

Triglycerides containing aspirin in place of one or more fatty acid residues of the molecule have been synthesized. Metabolism of the compound with the labelled (14C) drug residue introduced specifically into the 2-position of the triglyceride is reported. Plasma salicylate concentrations with this synthetic glyceride were determined and compared with those obtained with commercially available aspirin labelled with the 14C-isotope. Both compounds gave a therapeutic concentration of salicylate in the plasma after ingestion. The 1,3-di-fatty acyl-2-aspirin glyceride was absorbed through the intestine as 2-aspirin monoglyceride, some 20% of which was transported through the thoracic-duct chyle and about 30% through the portal system. Whereas pronounced ulceration of the rat stomach occurred with free aspirin, the above fatty acyl glyceride of aspirin produced no ulceration.