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PubMed1998

Thermal analysis as a screening technique in preformulation studies of picotamide solid dosage forms.

The potential compatibilities of several commonly used pharmaceutical excipients with picotamide were evaluated using differential scanning calorimetry (DSC). The effects of aging and of mechanical treatment (blending, grinding, or kneading) of samples were also evaluated. Hot-stage microscopy (HSM) and scanning electron microscopy (SEM) were used as complementary techniques to implement and assist in interpretation of the DSC results. DSC analysis evidenced a noticeable modification of drug thermal features in the mixtures with palmitic acid, stearic acid, stearyl alcohol, polyethylene glycol (PEG) 20,000, and sorbitol, but HSM analysis showed that the DSC behavior was mainly because of the drug dissolution in the melted excipient, which allowed the presence of important solid-solid interactions to be excluded. Compatibility with Mg stearate was also found, even if sample manipulation induced the partial conversion of Mg stearate in a pseudo-polymorphic modification. Mechanical stress displayed an increased hygroscopicity of mixtures with glucose and lactose, as well as some solid-solid interactions with lactose and mannitol.

Calorimetry, Differential Scanning↗

PubMed2001

[Residual chemicals in natural rubber products for food contact use].

The residues of additives and other chemicals were investigated by GC/MS in natural rubber products for food contact, which included nipples, packing, gloves and a net for ham. The packings and gloves contained 980-6,570 micrograms/g of vulcanization accelerators, such as zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate (EZ), zinc di-n-buthyldithiocarbamate (BZ) and 2-mercaptobenzothiazole. Some samples contained BHT, Irganox 1076 and Yoshinox 2246R as antioxidants; dibutyl phthalate and di(2-ethylhexyl) phthalate as plasticizers; and palmitic acid, stearic acid, palmitamide, stearamide and hydrocarbons as lubricants. Two unknown peaks were identified as stigmasterol and beta-sitosterol, and others were estimated to be fucosterol, oryzanol and alpha-sitosterol. These sterols are widely distributed in plants, so their origin was presumed to be the rubber plants. The sterols were detected at a level of 340-2,940 micrograms/g in all natural rubber samples. A migration test was carried out for some samples. No chemicals were released into water, 4% acetic acid or 20% ethanol at 60 degrees C for 30 min, though BHT, Yoshinox 2246R, EZ, BZ and sterols were released into n-heptane at 25 degrees C for 60 min.

Antioxidants↗

PubMed1999

The effect of palm oil, lard, and puff-pastry margarine on postprandial lipid and hormone responses in normal-weight and obese young women.

Only a few studies have been published on the postprandial effects of different fatty acids in obese subjects. Therefore, the present study investigated the effects of three test meals containing palm oil (PO), lard (LD), or puff-pastry margarine (PPM), all normal dietary ingredients, on postprandial lipid and hormone responses in normal-weight and obese young women. The study was performed as a randomized, crossover design. The fats differed in the content of palmitic acid, stearic acid, and trans monounsaturated fatty acids allowing a dietary comparison of different 'solid' fatty acids. The obese women had significantly higher fasting concentrations and postprandial responses of plasma total triacylglycerol (TAG), chylomicron-TAG, and insulin compared with the normal-weight women but there was no significant difference in the postprandial responses between the three test meals. The obese women had fasting concentrations of leptin four times greater than the normal-weight women. There were no postprandial changes in the concentrations of leptin. The fasting concentrations of HDL-cholesterol were significantly lower in the obese women than in the normal-weight women, whereas there was no significant difference between the two groups in the concentrations of total cholesterol or LDL-cholesterol. These results provide evidence that obese women have exaggerated lipid and hormone responses compared with normal-weight women but the different contents of saturated and trans monounsaturated fatty acids provided by PO, LD, and PPM have no effect in either group.

Adult↗

PubMed1997

[Chemical constituents of fructus Amomi].

Seven compounds have been isolated from Fructus Amomi. They were identified as bornyl acetate, camphor, borneol, beta-sitosterol, vanillic acid, stearic acid and palmitic acid. The vanillic acid was found in this medicine for the first time. Fifty-seven components were identified from the volatile oil of Fructus Amomi on the basis of GC-MS analysis. Eight components in the volatile oil over 1% in content are bornyl acetate, camphor, borneol, limonene, camphene, myrecene, carene-3 and alpha-terpeneol.

Drugs, Chinese Herbal↗

PubMed2002

Effects of free fatty acid on polymerization of islet amyloid polypeptide (IAPP) in vitro and on amyloid fibril formation in cultivated isolated islets of transgenic mice overexpressing human IAPP.

BACKGROUND: Islet amyloid polypeptide (IAPP) is deposited as amyloid in the islets of Langerhans in type 2 diabetes. The mechanism behind the formation of the cytotoxic fibrils is unknown. Islet amyloid develops in a mouse IAPP null mouse strain that expresses human IAPP (+hIAPP/-mIAPP) after 9 months on a high-fat diet. Herein we investigate the effect that individual free fatty acids (FFAs) exert on formation of amyloid-like fibrils from synthetic IAPP and the effects of FFAs on IAPP polymerization in +hIAPP/-mIAPP islets cultivated in vitro. MATERIALS AND METHODS: In the study myristic acid, palmitic acid, stearic acid, oleic acid, and linoleic acid were used together with albumin. Thioflavin T (Th T) assay was used for quantification of amyloid-like fibrils. Islets were isolated from the +hIAPP/-mIAPP transgenic strain and cultured in the presence of the FFAs for 2 days. Immuno-electron microscopy was used for evaluation. RESULTS: The Th T assay showed that all studied FFAs potentiated fibril formation but that myristic acid revealed the highest capacity. In some cells from cultured islets, intragranular aggregates were present. These aggregates had a filamentous appearance and labeled with antibodies against IAPP. In some cells cultured in the presence of linoleic acid, large amounts of intracellular amyloid were present. Earlier, this has not been observed after such a short incubation period. CONCLUSIONS: Our studies suggest that FFAs can potentiate amyloid formation in vitro, probably without being integrated in the fibril. Cultivation of +hIAPP/-mIAPP transgenic mouse islets with FFAs results in altered morphology of the secretory granules with appearance of IAPP- immunoreactive fibrillar material. We suggest that such fibrillar material may seed extracellular amyloid formation after exocytosis.

Amyloid↗

PubMed1992

[Chemical constituents of the roots of Ostericum grosseserratum (Maxim.) Kitag].

This paper reports the isolation of eleven compounds from the roots of Ostericum grosseserratum, of which nine compounds were elucidated as myristic acid, palmitic acid, stearic acid, octacosanoic acid, succinic acid, beta-sitosterol, sitosterol-beta-D-glucoside, isoscopletin and sucrose. The results are helpful in the study of plant taxonomy.

Drugs, Chinese Herbal↗

PubMed2003

[Topical administration of an hyperoxygenated fatty acid compound. Preventive and curative effects on pressure ulcer].

INTRODUCTION: Hyper-oxygenized acidic fats are a very useful topical use product for preventing pressure ulcers and to treat stage I pressure ulcers. Mepentol is a hyper-oxygenized acidic fats product (linoleic acid, gamma linolenic acid, oleic acid, palmitic acid, stearic acid, palmitoleic acid, arachidonic acid and eicosenoic acid) with extracts of Equisetum Avrense and Hypericum Perforatum. It works in three main facets: improve as is possible the epidermis's resistance, repair the damage to the epidermis produced by a prolonged pressure, and restore capillary circulation and counter arrest the effect of oxygen radicals produced during reactive hyperemia which are caused by periods of prolonged pressure. The exclusive formula, based on hyperoxygenized acidic fats and the above referred plant extracts, gives to Mepentol a demonstrated effectiveness, and also special features, like speed of action, great speed of topical absorption and a peculiar fragrance. PATIENTS, MATERIAL AND METHOD: In order to evaluate the tissue level effect of Mepentol, we carried out an experimental research project based on two different objectives: determine the effect at capillary circulation level in heels of healthy volunteers and in patients under risk of developing pressure ulcers, a well as in the treatment of stage I pressure ulcers in patients under high risk of developing pressure ulcers. To do so, the authors determined the capillary blood flow by means of a Doppler laser flow meter. RESULTS: After the application of a hyper-oxygenized acidic fats product, the authors noted an increase of 122.29 +/- 68.74% in flow units related to base values. The authors also observed an increase in microcirculation in heels of patients under high risk of developing pressure ulcers, as well as those who suffer from stage I lesions. These increases remain constant over long periods of time. COMMENTARY: Based on the tests carried out, Mepentol shows an undoubtable effect which improves local circulation in zones under risk of developing pressure ulcers as well as for stage I lesions; this supports the use of this product as a preventive measure against pressure ulcers and as treatment for stage I lesions.

Administration, Topical↗

PubMed2006

The positive feedback role of arachidonic acid in the platelet-derived growth factor-induced signaling in lens epithelial cells.

PURPOSE: Platelet-derived growth factor (PDGF)-stimulated cell proliferation has been associated with reactive oxygen species (ROS)-mediated redox signaling. This study examined the role of arachidonic acid (AA) in PDGF-stimulated ROS generation in human lens epithelial B3 cells (HLE B3). METHODS: PDGF (1 ng/ml)-stimulated ROS generation was examined using dichlorofluorescein (DCFH)-activated fluorescence by laser confocal microscopy while AA (30-150 muM)-stimulated superoxide anion production was measured using lucigenin-amplified chemiluminescence in serum-starved HLE B3 cells. PDGF-stimulated AA release was quantified by cells prelabeled with (3)H-AA with and without the presence of cytosolic phospholipase A(2) (cPLA(2)) inhibitor (AACOCF(3)) and mitogen-activated protein (MAP) kinases (MEK) inhibitor (U0126). Western blot analysis was used to characterize the activated MAP kinase components in cell lysates or protein kinase C (PKC) translocation in isolated cytosolic and membrane fractions. Specific inhibitors to various enzymes were used in the study, including GF109203X for pan protein kinase C (PKC), AACOCF3 for cytosolic phospholipase A2 (cPLA(2)), U0126 for MEK, and DPI for NADPH oxidase. Inhibitors for AA metabolism were also used to examine the role of AA in PDGF-stimulated ROS generation, including CDC and NDGA for pan lipoxygenase, AA861 for 5-lipoxygenase, indomethacin for cycloxygenase, and ketoconazole for cytochrome p450. RESULTS: We found that PDGF-stimulated ROS was eradicated by inhibitors to MEK, cPLA(2), 5-lipoxygenase, NADPH oxidase, or PKC. PDGF-stimulated AA release depended on both active cPLA(2) and ERK1/2. Exogenous AA showed a concentration-dependent ROS generation via NADPH oxidase activation that was insensitive to MEK inhibitor, but sensitive to PKC inhibitor, and could be attenuated by superoxide dismutase (SOD), mannitol, or DPI. This effect of AA was specific as other long chain fatty acids (leinoleic acid, stearic acid), or AA derivatives (eicosa-11Z, 14Z, 17Z-trienoic acid (20:3) and eicosa-11Z, 14Z-dienoic acid (20:2)) were ineffective. Inhibitor to lipoxygenase, in particular the 5-isoform, but not cycloxygenase or cytochrome p450, could diminish AA-stimulated luminescence generation. Western blot analysis showed that AA-treated cells transiently activated ERK1/2 and JNK, but not p38, in a time- and dose-dependent manner that was similar to that of PDGF. Finally, PDGF-stimulated PKC translocation depended on AA release while AA-stimulated PKC translocation was eradicated by lipoxygenase inhibition. CONCLUSIONS: We conclude that PDGF signaling in HLE B3 cells is mediated by AA and its lipoxygenase metabolites, which provide a positive feedback loop for PDGF action, as AA and its metabolites can mobilize PKC and other factors needed for NADPH oxidase assembly and activation for ROS generation to facilitate cell proliferation. We further propose the role of AA in PDGF signaling.

Animals↗

PubMed2006

[Determination of fatty acids and organic acids in Ranunculus ternatus Thunb using GC-MS].

The determination of fatty acids and organic acids in Chinese medicinal plant Ranunculus ternatus Thunb using GC-MS was studied. The Ranunculus ternatus Thunb from Henan province was cut into less than 20 mesh pieces, then extracted by petroleum ether or ether in refluxing and esteried, and finally was determined using GC-MS. The results show that there are 23 kinds of organic compounds in the Chinese medicinal plant Ranunculus ternatus Thunb from Henan, among which 15 kinds of fatty acids were identified, including myristic acid, palmitic acid, stearic acid, oleic acid, linolenic acid, eicosanoic acid, docosanoic acid etc. The unsaturated fatty acids and oleic acid account for 58.19% and 35.68% of the total organic compounds respectively. The kinds of fatty acid in petroleum ether extract and ether extract are the same.

Alkanes↗

PubMed1989

[Studies on the chemical constituents of Arisaema fargesii Buchett].

Heptatriacontane, benzoic acid, succinic acid, palmitic acid, stearic acid, beta-sitosterol, stigmasterol, daucosterol, D-mannitol, D-glucose, sucrose and choline chloride were isolated from the roots of Arisaema fargesii collected from Gansu Province. Their structures were elucidated by spectroscopic methods and a few chemical transformations. The twelve compounds have not been reported before as constituents of Arisaema fargesii.

Antineoplastic Agents, Phytogenic↗

PubMed1989

The effect of delta-9-tetrahydrocannabinol (delta-9-THC) on the release of nonesterified fatty acids in various brain structures.

There was studied the effect of repeated administration of delta-9-THC (10 mg/kg per os for two days) on the level of nonesterified fatty acids (NEFA) in the brain structures of laboratory rats. Palmitic acid, stearic acid, oleic acid and arachidonic acid were estimated with the help of gas chromatography after preliminary separation by TLC. After administration of delta-9-THC, the levels of NEFA decreased in the brain cortex, the brain stem and most in the hypothalamus. The NEFA decrease after delta-9-THC administration is in harmony with the functional inhibition of CNS, provoked by this substance.

Animals↗

PubMed1989

[Screening of drugs and chemicals by wide-bore capillary gas chromatography with flame ionization and nitrogen phosphorus detectors].

A method is presented for forensic toxicological screening of drugs and chemicals in blood and urine by wide-bore capillary gas chromatography with flame ionization detectors (FID) and nitrogen phosphorus detectors (NPD). The presence of drugs and chemicals in blood and urine specimens was confirmed by comparing these gas chromatograms with those of typical drug-free specimens. Peak components of drug-free specimens were piperidone, p-cresol, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, n-butylphthalate, bis (2-ethylhexyl) phthalate, squalene, cholesterol and two alcohols (unidentified) on FID chromatograms and were piperidone, indole, nicotine, cotinine, hydroxycotinine, caffeine and several unknown urine constituents on NPD chromatograms. In practical cases, the presence of drugs and chemicals in postmortem specimens was easily ascertained by the present method.

Adult↗

PubMed1988

Biosynthesis of placental alkaline phosphatase and its post-translational modification by glycophospholipid for membrane-anchoring.

The biosynthesis and post-translational modification of placental alkaline phosphatase were studied in human choriocarcinoma cells, JEG-3. Pulse-chase experiments with [35S]methionine demonstrated that placental alkaline phosphatase was synthesized as a major precursor form with Mr 63,000, which was then converted to a mature form with Mr 66,000, by processing of its N-linked oligosaccharides from the high-mannose type to the complex type. In addition, the two forms of the protein were found to be modified by a glycophospholipid, components of which were characterized by metabolic incorporation into placental alkaline phosphatase of 3H-labeled compounds such as myo-inositol, palmitic acid, stearic acid, mannose, glucosamine, and ethanolamine. When placental alkaline phosphatase labeled with these compounds was treated with phosphatidylinositol-specific phospholipase C or papain, the phospholipase C removed only the 3H-labeled fatty acids, whereas papain, that is known to cleave the C-terminal region, released all the radioactive glycolipid components including [3H]ethanolamine. More detailed analysis with shorter pulse-chase experiments demonstrated that placental alkaline phosphatase was primarily synthesized as a form with Mr 64,500 which was not yet labeled with [3H]palmitic acid. This form was converted by papain digestion to the above-mentioned major precursor with Mr 63,000. Taken together, these results suggest that placental alkaline phosphatase is initially synthesized as the precursor with Mr 64,500, which is immediately converted to the intermediate form with Mr 63,000 by simultaneously occurring proteolysis of the C terminus and replacement by the glycophospholipid, and finally to the mature form with Mr 66,000 by terminal glycosylation of its N-linked oligosaccharides. The glycophospholipid thus attached is considered to function as the membrane-anchoring domain of placental alkaline phosphatase.

Alkaline Phosphatase↗

PubMed1986

Ganglioside enhancement of neuronal differentiation, plasticity, and repair.

Gangliosides are carbohydrate-rich complex lipids of large size and great complexity which are found in cell membranes, especially neuronal cell membranes. They are present in the external leaflet of the membrane. The hydrophobic moiety, consisting of sphingosine and fatty acid (stearic acid, 95%), is inserted into the membrane, while the hydrophilic moiety, consisting of sialic acid (NANA) and other carbohydrates, protrudes towards the extracellular fluid. Although gangliosides were discovered some 50 years ago, their potential role in neuronal functions has been appreciated only recently. During development, their composition and concentration change in a variety of animal species. Their role is indicated from studies which have shown that abnormalities in ganglioside metabolism can have a severe impairing effect on normal development. The mouse mutant weaver is characterized by cerebellar granule cell death, which is correlated by the lack of GM1 expression on the neuronal surface. On the other hand, inborn metabolic errors causing ganglioside accumulation in neurons (GM1 gangliosides) are correlated to an aberrant neurite outgrowth. A further appreciation of ganglioside action has been obtained either by adding gangliosides to neurons in culture or by treating animals during neuronal regeneration. It was found that these agents increased the rate and extent of sprouting of regenerating axons and enhanced neuronal differentiation and sprouting in vitro. Such effects were dependent upon the presence of the growth factor in the bathing medium; ganglioside incorporation, however, did not alter nerve growth factor (NGF) binding and internalization, indicating that some membrane events triggered by ganglioside incorporation may be relevant in neuronal differentiation and sprouting. More recently, we have obtained evidence showing that neurons from animals treated with gangliosides are more resistant to anoxia and ionic unbalances. It seems that ganglioside treatment prevents the decay of some key enzyme activity, such as Na+-K+-ATPase occurring after trauma. Indeed, the recent literature suggests that gangliosides may play an important role during development and, when injected into animals, enhance reparatory events in the central and peripheral nervous system.

Animals↗

PubMed1987

Identification of a novel insulin-sensitive glycophospholipid from H35 hepatoma cells.

This study identifies and partially characterizes an insulin-sensitive glycophospholipid in H35 hepatoma cells. The incorporation of [3H]glucosamine into cell lipids was investigated. A major labeled lipid was purified by sequential thin layer chromatography using first an acid followed by a basic solvent system. After hydrochloric acid hydrolysis and sugar analysis by thin layer chromatography, 80% of the radioactivity in the purified lipid was found to comigrate with glucosamine. H35 cells were prelabeled with [3H]glucosamine for either 4 or 24 h and treated with insulin causing a dose-dependent stimulation of turnover of the glycophospholipid which was detected within 1 min. The purified glycolipid was cleaved by nitrous acid deamination indicating that the glucosamine C-1 was linked to the lipid moiety through a glycosidic bond. [14C]Ethanolamine, [3H]inositol, and [3H]sorbitol were not incorporated into the purified glycolipid. The incorporation of various fatty acids into this glycolipid was also studied. [3H]Palmitate was found to be preferentially incorporated while myristic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, and arachidonic acid were either not incorporated or incorporated less than 10% of palmitate. The purified glycolipid labeled with [3H]palmitate was cleaved by treatment with phospholipase A2 but was resistant to mild alkali hydrolysis suggesting the presence of a 1-hexadecyl,2-palmitoyl-glyceryl moiety in the purified lipid. Treatment of labeled glycophospholipid with phosphatidylinositol-specific phospholipase C from Staphylococcus aureus generated a compound migrating as 1-alkyl,2-acyl-glycerol and a polar head group with a size in the range from 800 to 3500. These findings coupled with the nitrous acid deamination demonstrate that glucosamine was covalently linked through a phosphodiester bond to the glyceryl moiety of the purified glycolipid. These findings suggest that insulin acts on this glycophospholipid by stimulating an insulin-sensitive phospholipase C. This unique glycophospholipid may play an important role in insulin action by serving as precursor of insulin-generated mediators.

Acetylation↗

PubMed1987

Structure of a triphosphonopentaosylceramide containing 4-O-methyl-N-acetylglucosamine from the skin of the sea hare, Aplysia kurodai.

A novel phosphonoglycosphingolipid named SGL-I containing 3 mol of 2-aminoethylphosphonate residues was isolated from the skin of a sea gastropod, Aplysia kurodai. The saccharide moiety of the glycolipid was characterized as 4-O-methyl-GlcNAc alpha 1----4GalNAc alpha-1----3 [6'-O-(2-aminoethylphosphonyl)Gal alpha 1----2] (2-aminoethylphosphonyl----6)Gal beta 1----4(2-aminoethylphosphonyl----6) Glc beta 1----1-ceramide. The major aliphatic components of the ceramide portion were palmitic acid, stearic acid, octadeca-4-sphingenine, and anteisononadeca-4-sphingenine. This glycolipid is unique in containing 4-O-methyl-N-acetylglucosamine and 3 mol of 2-aminoethylphosphonate residues, one of which is attached to C-6 of glucose.

Acetylglucosamine↗

PubMed1979

[Fatty acid metabolism in primary hyperlipoproteinemia (HLP) (author's transl)].

The fatty acid spectra of cholesterol ester and triglyceride fractions separated by thin-layer chromatography were analyzed by gas chromatography in the sera of 252 patients with primary HLP (with 53 cases of type IIa, 48 cases of type IIb, and 151 cases of type IV) and 60 healthy persons. Showing significantly increased values in the cholesterol ester fraction for HLP of types IIa and IIb as well as in the triglyceride fraction for HLP of types IIb and IV were palmitic acid, stearic acid, palmitoleic acid, oleic acid, and eicosatrienic acid. Significantly reduced percentages were obtained for linoleic acid, linolenic acid, arachidonic acid, and eicosapentaenic acid in the same fractions for these types. Possible causes include disturbances of the fatty acid metabolism in the liver, increased selective reesterification of fatty acids of the lipolytic process, and partially altered LCAT activity.

Adult↗

PubMed1983

Isolation and characterization of a 4-O-methylglucuronic acid-containing glycosphingolipid from spermatozoa of a fresh water bivalve, Hyriopsis schlegelii.

A novel glycosphingolipid, provisionally named Lipid IV (Hori, T., Sugita, M., Ando, S., Kuwahara, M., Kumauchi, K., Sugie, E., and Itasaka, O. (1981) J. Biol. Chem. 256, 10979-10985), was obtained from spermatozoa of the fresh water bivalve, Hyriopsis schlegelii. The yield of the glycolipid was 2.2 mg/g of dried spermatozoa. The structure of the glycolipid was elucidated by partial hydrolysis, permethylation analysis, and proton nuclear magnetic resonance. The following structure is proposed: GlcA4Me beta 1-4(GalNAc3Me alpha 1-3)Fuc alpha 1-4GlcNAc beta 1-2Man alpha 1-3(Xyl beta 1-2)Man beta 1-4Glc beta 1-Cer. The acidic glycolipid is unique in containing 4-O-methylglucuronic acid as well as an internally located fucose. Palmitic acid, stearic acid, and C18-sphingosine are the major aliphatic components. This composition is similar to those of other neutral spermatozoan glycolipids, Lipid I (Hori, T., Sugita, M., Kanbayashi, J., and Itasaka, O. (1977) J. Biochem. (Tokyo) 81, 107-114) and Lipid II (Hori, T., Takeda, H., Sugita, M., and Itasaka, O. (1977) J. Biochem. (Tokyo) 82, 1281-1285), suggesting a possible metabolic relationship among them.

Acidic Glycosphingolipids↗