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Isolation and identification of hematopoietic stem cell-stimulating substances from Kampo (Japanese herbal) medicine, Juzen-taiho-to.

We have previously found that TJ-48 has the capacity to accelerate recovery from hematopoietic injury induced by radiation and the anti-cancer drug mitomycin C (MMC). The effects are found to be due to its stimulation of spleen colony-forming unit (CFU-S) counts on day 14. In the present study, we attempt to isolate and purify the active components in TJ-48 extracts using a new in vitro hematopoietic stem cell (HSC) assay method. n-Hexane extract from TJ-48 shows a significant stimulatory activity. The extract is further fractionated by silica gel chromatography and HPLC in order to identify its active components. 1H-NMR and GC-EI-MS indicate that the active fraction is composed of free fatty acids (oleic acid and linolenic acid). When 27 kinds of free fatty acids (commercially available) are tested using the HSC proliferating assay, oleic acid, elaidic acid, and linolenic acid are found to have potent activity. The administration of oleic acid to MMC-treated mice enhances CFU-S counts on days 8 and 14 to twice the control group. These findings strongly suggest that fatty acids contained in TJ-48 actively promote the proliferation of HSCs. Although many mechanisms seem to be involved in the stimulation of HSC proliferation, we speculate that at least one of the signals is mediated by stromal cells, rather than any direct interaction with the HSCs.

Animals↗

Substrate dependence of the postischemic cardiomyocyte recovery: dissociation between functional, metabolic and injury markers.

Defining the substrate that influences the most favourably the myocardial post-ischemic recovery is subject of debates, due to dissociation between functional and biochemical benefits. Hence, we studied the effects of either glucose or different fatty acids on the functional and metabolic recovery of post-ischemic cardiomyocytes in a substrate-free hypoxia model of simulated ischemia-reperfusion. Rat cardiomyocytes were submitted to a 2.5 h simulated ischemia followed by a 2 h reoxygenation without substrate (control), or with either glucose, octanoic acid, oleic acid, or elaidic acid. During simulated ischemia, electromechanical function gradually disappeared while the cellular viability and mitochondrial function declined. During control simulated reperfusion, cardiomyocytes recovered near normal function but a significant reduction in the action potential amplitude and rate persisted. The addition of glucose or oleic acid during simulated reperfusion promoted a faster, better and sustain functional recovery. Amongst the fatty acids, the functional recovery was slower with elaidic and octanoic acids as compared with oleic acid. The mitochondrial function was better improved during simulated reperfusion with glucose than with the tested fatty acids, among which elaidic acid was the less unfavourable. Paradoxically, the addition of whichever substrate during simulated reperfusion tended to worsen the cellular viability. Thus, cardiomyocytes recovery strongly relies on the characteristics of the substrate supplied at the onset of simulated reperfusion: glucidic or lipidic nature, chain-length, insaturation degree. Moreover, these data suggest that defining the appropriateness of a given substrate for the post-ischemic cardiomyocyte recovery is closely related to the functional and the biological endpoints in consideration.

Animals↗

Interaction of Propionibacterium acnes with skin lipids in vitro.

Propionibacterium acnes is the predominant microbial resident within the pilosebaceous follicles of sebum-rich areas of human skin. This study investigated the effects of known hydrophobic components of sebum on the physiology and nutrition of this microorganism, grown anaerobically at 33 degrees C, under defined conditions using continuous culture techniques. The medium used was chemically defined, comprising eight amino acids, with glucose as the main carbon energy source, and the culture pH was maintained at 5.6. The range of sebum lipids assayed was based on the C18 monounsaturated fatty acid 9-cis-octadecenoic acid (oleic acid). Stock micronized solutions were aseptically pulsed into continuous cultures in the presence and absence of glucose, and nutritional effects monitored. None of the lipid substrates significantly affected P. acnes growth either in terms of maximum specific growth rate (mu max) or final culture biomass yield. Glycerol (3 mg ml-1) was found to be a poor carbon/energy source in comparison to glucose. Bacterial cells did, however, adhere with varying degrees, to the different lipid species, with maximum adherence occurring with the free fatty acid. This observation was confirmed by preliminary uptake experiments using [14C]oleic acid. The interactive site for cell adherence may be the lipid-fibrillar layer associated with the cell surface of P. acnes, as discerned in electron microscopical studies. The findings of this investigation suggest that one function of the P. acnes lipase may be to aid colonization within the pilosebaceous follicle, by promoting cell adherence to components such as oleic acid.

Glucose↗

Heteronuclear NMR analysis of unsaturated fatty acids in poly(3-hydroxyalkanoates). Study of beta-oxidation in Pseudomonas putida.

Poly(3-hydroxyalkanoates) (PHAs) were isolated from Pseudomonas putida KT2442 cultivated on petroselenic acid, oleic acid, and linoleic acid to study beta-oxidation of unsaturated fatty acids. Both saturated and unsaturated medium chain length 3-hydroxy fatty acids were found to be constituents of these polymers. With the aid of proton-detected multiple quantum coherence and proton-detected multiple bond coherence NMR spectra the structures of the unsaturated monomers were identified as 3-hydroxy-5-cis-tetradecanoate for PHA produced on oleic acid, and 3-hydroxy-6-cis-dodecanoate and 3-hydroxy-5-cis-8-cis-tetradecadienoate for PHA produced on linoleic acid. The identified structures, which are derived from fatty acid degradation intermediates, indicate a degradation of oleic acid via the enoyl-CoA isomerase-dependent route and a degradation of linoleic acid via the dienoyl-CoA reductase-dependent route.

Carbon Isotopes↗

Effects of fatty acids on Na/Ca exchange in cardiac sarcolemmal membranes.

Three structurally distinct amphiphiles palmitic acid, oleic acid, and palmityl carnitine were studied to determine their effects on sodium dependent calcium uptake by purified cardiac sarcolemmal vesicles (PSL). Sodium dependent calcium uptake by PSL when studied over a 20 min reaction period was composed of an initial rapid uptake (20.9 +/- 0.93 nmol/mg X 30 s, mean +/- S.E. n = 20) a plateau in calcium content (42.4 +/- 3.2 nmol/mg, mean +/- S.E. n = 20) and a slow spontaneous release characterized by a first order rate constant of 0.68 +/- 0.08/h (mean +/- S.E. n = 18). Both palmityl carnitine and palmitic acid inhibited, whereas oleic acid stimulated initial calcium uptake. All three amphiphiles shortened the time to peak calcium content, inhibited peak calcium content and increased the rate constant for calcium release. All these effects were observed at fatty acid: membrane phospholipid mole ratios of 0.67 : 1 to 1.67 : 1 for oleic acid and palmityl carnitine and 0.02 : 1 to 0.42 : 1 for palmitic acid. These effects do not reflect disruption of membrane vesicle structure and may be explained, at least in part, by amphiphile induced increases in sarcolemmal membrane ion permeability. Although amphiphile accumulation has been implicated in the pathogenesis of cellular abnormalities in the ischemic myocardium, this study has shown that large amounts of amphiphile relative to membrane lipid are required to alter sarcolemmal membrane function in vitro.

Animals↗

The binding of L-tryptophan to serum albumins in the presence of non-esterified fatty acids.

Bovine, human and rat serum albumins were defatted and palmitic acid, oleic acid and lauric acid added in various molar ratios. The binding of L-tryptophan to these albumins was measured at 20 degrees C in a 0.138 M salt solution at pH 7.4, by using an ultrafiltration technique, and analysed in terms of n, the number of available tryptophan-binding sites per albumin molecule, with apparent association constant, k. 2. n and k were 0.90 and 2.3x10(-4)M(minus-1) respectively for defatted bovine serum albumin and 0.87 and 9.7x10(-3)M(-minus-1) for human albumin. Addition of palmitic acid did not decrease n until the molar ratio, fatty acid/bovine albumin, approached and exceeded 2. The decrease in k was small and progressive. In contrast, lauric caused a marked decrease in n and k at ratios as low as 0.5. A similar distinction between the effects on n of palmitic acid and oleic acid and those of lauric acid was seen for human albumin. k for human albumin was not significantly affected by fatty acids under the conditions studied. 3. It is concluded that primary long-chain fatty acid sites interact only weakly with the tryptophan site on albumin and that inhibition of tryptophan binding occurs when secondary long-chain sites are occupied. Primary medium-chain fatty acid sites are distinct from primary long-chain sites but may be grouped with secondary long-chain sites. 4. The relationship between free and bound tryptophan in samples of rat plasma (Stoner et al., 1975) is discussed in terms of a similar but limited study of rat albumin.

Animals↗

Monohydroxylation and esterification as determinants of the effects of cis- and trans-9-octadecenoic acids on the permeation of hydrocortisone and 5-fluorouracil across hairless mouse skin in vitro.

The effects of cis-9-octadecenoic acid (oleic acid) and of a group of chemically related cis- (ricinoleic acid) and trans- (ricinelaidic acid) 12-monohydroxylated derivatives and their corresponding ethyl and methyl esters on the skin permeation of model hydrophobic (hydrocortisone, log K=1.61) and hydrophilic (5-fluorouracil, log K=-0.89) drugs was investigated in vitro using excised hairless mouse skin. Drug solutions were prepared in propylene glycol, with and without the addition of a fatty acid to a level of 5%. Whereas the addition of oleic acid markedly enhanced the transdermal flux of both drugs relative to a sample in propylene glycol alone (hydrocortisone approximately 1800-fold; 5-fluorouracil approximately 330-fold), that of a cis- or trans-12-monohydroxylated analog of oleic acid resulted in only a small increase (1.4-2.7-fold for hydrocortisone; 4.4-6.6-fold for 5-fluorouracil). On the other hand, the methyl and ethyl esters of cis- and trans-12-hydroxy-9-octadecenoic acid exerted a much greater enhancing effect (327-720-fold for hydrocortisone, 42-74-fold for 5-fluorouracil) than the corresponding parent fatty acids. Furthermore, whereas the ethyl esters were found to have a greater effect on the skin permeation of hydrocortisone than the methyl esters, the reverse was true with regards to 5-fluorouracil. Additionally, the esters of trans-12-hydroxy-9-octadecenoic acid promoted permeation to an extent comparable to that achieved with their cis-counterparts.

Animals↗

Long-chain fatty acids increase cellular dopamine in an immortalized cell line (MN9D) derived from mouse mesencephalon.

The lysate of an immortalized monoclonal cell line derived from the striatum (X61) contains a dopaminergic stimulatory activity that is capable of increasing the dopamine content of an immortalized mouse mesencephalic cell line (MN9D) which expresses a dopaminergic phenotype. Purification of an isoamyl alcohol extract of this lysate and subsequent identification by NMR spectroscopic analysis demonstrated that the dopaminergic stimulatory activity contained within the lysate was a mixture of 80-90% cis-9-octadecenoic acid (oleic acid) and 10-20% cis-11-octadecenoic acid (cis-vaccenic acid). The effect of oleic acid on MN9D dopamine is a prolonged event. MN9D dopamine increases linearly over a 48 h period suggesting the induction of an increased dopaminergic phenotype in these dividing cells. The ability to increase MN9D dopamine by oleic and cis-vaccenic acids is shared by a number of other long-chain fatty acids including arachidonic, linoleic, linolenic, palmitoleic, and cis-13-octadecenoic acid. The possibility that oleic or other relatively innocuous fatty acids might affect dopaminergic function in primary neurons is intriguing with respect to possible therapeutic approaches to the treatment of dopaminergic cell loss and the motor sequelae of Parkinson's disease.

Animals↗

Duodenal acidification and secretin, but not intraduodenal fat, inhibit human gastric acid secretion via prostaglandins.

BACKGROUND/AIMS: Acid and fat in the duodenum inhibit gastric acid secretion and increase plasma secretin. The role of prostaglandins and secretin in the inhibition of gastric acid secretion by duodenal infusion of hydrochloric acid and fat in healthy human volunteers was studied. METHODS: Gastric acid secretion was submaximally stimulated with intravenous pentagastrin followed by duodenal infusion of 0.1N hydrochloric acid, oleic acid, or intravenous secretin. To inhibit endogenous prostaglandins, the protocol was then repeated after indomethacin treatment. RESULTS: Duodenal fat infusion inhibited acid secretion 80% +/- 5% and was unaffected by indomethacin treatment. Intraduodenal acidification inhibited acid secretion by 43% +/- 8% and was reduced by indomethacin treatment to 15% +/- 4% (P < 0.01). Similarly, intravenous secretin inhibited acid secretion by 34% +/- 3%, which was decreased to 13% +/- 6% by indomethacin treatment (P < 0.01). The increase in plasma secretin levels after intraduodenal hydrochloric acid treatment was significantly greater than that observed with intravenous secretin or introduodenal oleic acid treatment; all were within the physiological range. Acid in the duodenum releases secretin, which inhibits gastric acid secretion at least in part via prostaglandins. In contrast, fat in the duodenum strongly inhibits gastric acid secretion via a nonprostaglandin pathway. CONCLUSIONS: Secretin is the predominant mediator for the inhibition of human gastric acid secretion induced by the presence of acid, but not fat, in the duodenum.

Adolescent↗

Effect of hydralazine on intrapulmonary shunt.

We compared the acute effects of bilateral arteriovenous may be related to levels of PvO2. The hydralazine-associated (p less than .05) decrease in resistance. Mixed venous oxygen fistulas to those of hydralazine infusion on hemodynamics and pulmonary gas exchange in dogs with pulmonary edema induced by administration of oleic acid. Oleic acid significantly (p less than .01) increased intrapulmonary shunt (Qsp/Qt) and pulmonary and systemic vascular resistance, and reduced cardiac output. Once the lesion stabilized, both opening the fistula and infusing hydralazine produced a similar and significant (p less than .01) increase in cardiac output, and a significant (p less than .05) decrease in resistance. Mixed venous oxygen tension (PvO2) closely followed the changes in cardiac output; however, PaO2 did not change. Qsp/Qt significantly (p less than .01) increased with the fistulas open and with hydralazine infusion. Closure of the fistulas or bleeding the animal at the end of the experiment reversed the changes in cardiac output and Qsp/Qt. The comparable increases in cardiac output and Qsp/Qt produced by opening the fistulas or infusing hydralazine may be related to levels of PvO2. The hydralazine-associated PvO2 increase indicates that this drug increased oxygen transport to the tissues even as Qsp/Qt became larger.

Animals↗

Effects of fatty acids and iontophoresis on the delivery of midodrine hydrochloride and the structure of human skin.

PURPOSE: The purpose of this work was to investigate if fatty acids can increase the iontophoretic delivery of midodrine hydrochloride through human dermatomed skin and to observe the effects of iontophoresis and fatty acids on skin using SEM. METHODS: After prehydration for 1 h, human dermatomed skin was treated with 0-0.3 M fatty acids (oleic acid, linoleic acid, decanoic acid, and lauric acid) in propylene glycol (PG) for 1 h. Then the fatty acid solution was replaced by 1% midodrine hydrochloride aqueous solution, and 0.1 mA/cm2 constant current was applied. Samples were taken over 24 h and analyzed by HPLC. After the treatments outlined above, the epidermis was separated, fixed with glutaraldehyde, and dehydrated for SEM. RESULTS: SEM studies revealed that only 1 h of treatment with fatty acids opened up the tightly compact stratum corneum cell layer, and the permeation study showed a significant increase of the permeability of skin to midodrine hydrochloride after fatty acid treatment. CONCLUSIONS: Using 5% oleic acid pretreatment, with the electrical current offset at 0.1 mA/cm2, the daily delivery of midodrine hydrochloride can provide an adequate clinical application. The enhancement of passive and iontophoretic delivery by fatty acids may be occurring through the same mechanism.

Adjuvants, Pharmaceutic↗

Intracolonic fat inhibits gastric acid secretion independent of gastrin release in the dog.

The purpose of this study was to examine the effect of perfusion of the colon with a fatty acid (oleic acid) on peptone-stimulated gastric acid secretion and release of gastrin in conscious dogs. Gastric acid secretion was monitored by continuous intragastric titration. Perfusion of the colon with sodium oleate (24 mmol/hr) inhibited gastric acid secretion (14.2 +/- 2.6 meq/hr) stimulated by a peptone meal (1%) significantly (P less than 0.05) when compared to perfusion of the colon with saline alone (20.1 +/- 1.6 meq/hr). The serum elevation in gastrin in response to intragastric instillation of the peptone meal was not affected by the colonic perfusion of oleic acid. Plasma concentrations of peptide YY (PYY) increased significantly in response to perfusion of the colon with saline or sodium oleate, and the integrated release of PYY in response to sodium oleate [6.9 +/- 2.8 ng (60-120) min/ml] was significantly greater than the response to saline [3.1 +/- 0.7 ng (60-120) min/ml]. The results of this study indicate that inhibition of gastric acid secretion by perfusion of the colon with fat is not due to an inhibition of gastrin release. In addition, because PYY is an inhibitor of gastric acid secretion, it is possible that PYY participates as an inhibitor of gastric acid secretion by the colon.

Animals↗

[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↗

Unsaturated fatty acid modulation of glucocorticoid receptor binding in L2 cells.

Glucocorticoids stimulate fatty acid synthesis during late fetal lung development by inducing fatty acid synthetase. To determine whether fatty acids modulate glucocorticoid receptor binding, we investigated the in vitro effect of fatty acids on [3H]triamcinolone acetonide (TA) binding to the cytosolic glucocorticoid receptor in L2 cells, a cell line cloned from the adult rat type II cell. The L2 cell glucocorticoid receptor exhibited specific binding of [3H]TA which was saturable and appeared to be a single species of binding sites with an apparent KD = 4.9 +/- 3.7 nM and Bmax = 395.4 +/- 84.4 fmol/mg protein. The receptor had the ligand specificity typical of a physiologically relevant glucocorticoid receptor. Long-chain unsaturated fatty acids (oleic acid [18:1], linoleic acid [18:2], and arachidonic acid [20:4]) markedly inhibited [3H]TA specific binding in a dose-dependent manner, but long-chain saturated fatty acids (myristic, 14:0; palmitic, 16:0; and stearic acid, 18:0) and phospholipids had no effect. Scatchard analysis revealed a noncompetitive type of inhibition by unsaturated fatty acids. This suggests that unsaturated fatty acids modulate L2 cell glucocorticoid receptor by binding to sites different from the glucocorticoid binding sites in the receptor. We propose that unsaturated fatty acids may act as negative feedback modulators of glucocorticoid-receptor binding in the lung.

Animals↗

Injury induced by fatty acids or bile acid in isolated human colonocytes prevented by calcium.

Measurement of the modulation of the growth fraction of isolated normal colonocytes from adult subjects in primary monolayer culture was used as a sensitive quantitative assay to evaluate toxic effects of several endogenous compounds found within the colon. This assay was used to study the role of CaCl2 in blocking cell injury. When added simultaneously with the injurious agent, 5-10 mM CaCl2 blocked the toxicity of physiological concentrations of deoxycholic acid, oleic acid, palmitic acid and linoleic acid.

Calcium Chloride↗

Oleic acid-induced Ca2+ mobilization in human platelets: is oleic acid an intracellular messenger?

The purpose of this study was to explore the effect of oleic acid (OA) on intracellular Ca2+ mobilization in human platelets. When applied extracellularly, OA produced a concentration dependent rise in cytosolic [Ca2+] ([Ca2+]cyt) when extracellular [Ca2+] (Ca2+]ext) was zero (presence of EGTA), suggesting that OA caused an intracellular release of Ca2+. Intracellular Ca2+ release was directly proportional to entry of OA into platelets and OA entry was indirectly proportional to [Ca2+]ext. In permeabilized platelets, OA caused the release of 45Ca2+ from ATP dependent intracellular stores. Finally, our results show that thrombin stimulated the release of [3H]OA from platelet phospholipids. The saturated fatty acids stearic and palmitic acid did not stimulate an increase in [Ca2+]cyt under these conditions, but the unsaturated fatty acid, linolenic acid produced effects similar to those of OA, suggesting specificity among fatty acids for effects on [Ca2+]cyt. Taken together, our experiments suggest that OA which has been incorporated into platelet phospholipids was released into the cytosol by thrombin stimulation. Our experiments also show that OA stimulates Ca2+ release from intracellular stores. These results support the hypothesis that OA may serve as an intracellular messenger in human platelets.

Blood Platelets↗

Fatty acid composition and preservation of the Tyrolean Iceman and other mummies.

In anthropology, objective parameters to adequately describe storage conditions and the preservation of mummies have yet to be identified. Considering that fatty acids degrade to stable products, we analysed their profile in human mummies and in control samples by gas chromatography coupled to mass spectrometry (GC/MS). Originating from different epochs and civilizations, samples of the Tyrolean Iceman, other glacier corpses, a freeze dried mummy, corpses from a permafrost region, a corpse mummified immersed in water, and a desert mummy were evaluated. Chemometric analysis based on the concentrations of 16 fatty acids revealed the degree of similarity between anthropologic and fresh corpse samples, which was mainly influenced by the content of palmitic acid, oleic acid, and 10-hydroxystearic acid. The presence of 10-hydroxystearic acid was associated with immersion in water, whereas dry mummification was accompanied by high contents of oleic acid. Samples of the Tyrolean Iceman clustered between fresh tissue and those of other glacier corpses indicating the good preservation of this mummy. Thus, environmental post-mortem conditions were associated with characteristic fatty acid patterns suggesting that chemometric analysis of fatty acid contents may add to our knowledge about post-mortem storage conditions and the preservation of human corpses.

Fatty Acids↗

Chronic effects of different fatty acids and leptin in INS-1 cells.

The effects of long-term exposure of a pancreatic beta cell line, INS-1, to major free fatty acids (FFA; palmitic acid, oleic acid and linoleic acid) and leptin on insulin secretion and cell viability by C,N-diphenyl-N'-4,5 dimethylthiazol 2-yl tetrazolium bromide (MTT) assay were examined. The cells were incubated with 1 mmol/l of each FFA and 25 or 100 ng/ml leptin, alone or in combination, for 4, 24 or 48 h before the insulin secretion experiments. Palmitic acid (C 16:0) significantly suppressed cell viability, and suppressed insulin secretion at 24 h. Treatment with oleic acid (C 18:1) or linoleic acid (C 18:2) enhanced basal insulin secretion and diminished glucose-stimulated insulin secretion (GSIS) at 48 h. In these groups, there were no differences in cell viability as compared to cells treated without FFA. Leptin did not affect insulin secretion at 4, 24 and 48 h, and in the cells co-treated with FFA and leptin, leptin did not ameliorate lipotoxicity. These results suggest that, in INS-1 cells, different FFA have different patterns of lipotoxicity with chronic exposure, and leptin has little direct effect on insulin secretion.

Animals↗