Different Concentrations Of Oleic Acid Research Articles

Oleic acid-induced steatosis model establishment in LMH cells and its effect on lipid metabolism

Hepatic steatosis is a highly prevalent liver disease, yet research on it is hampered by the lack of tractable cellular models in poultry. To examine the possibility of using organoids to model steatosis and detect it efficiently in leghorn male hepatocellular (LMH) cells, we first established steatosis using different concentrations of oleic acid (OA) (0.05–0.75 mmol/L) for 12 or 24 h. The subsequent detections found that the treatment of LMH cells with OA resulted in a dramatic increase in intracellular triglyceride (TG) concentrations, which was positively associated with the concentration of the inducing OA (R2 > 0.9). Then, the modeled steatosis was detected by flow cytometry after NileRed staining and it was found that the intensity of NileRed-A was positively correlated with the TG concentration (R2 > 0.93), which demonstrates that the flow cytometry is suitable for the detection of steatosis in LMH cells. According to the detection results of the different steatosis models, we confirmed that the optimal induction condition for the establishment of the steatosis model in LMH cells is OA (0.375 mmol/L) incubation for 12 h. Finally, the transcription and protein content of fat metabolism-related genes in steatosis model cells were detected. It was found that OA-induced steatosis could significantly decrease the expression of nuclear receptor PPAR-γ and the synthesis of fatty acids (SREBP-1C, ACC1, FASN), increasing the oxidative decomposition of triglycerides (CPT1A) and the assembly of low-density lipoproteins (MTTP, ApoB). Sterol metabolism in model cells was also significantly enhanced (HMGR, ABCA1, L-BABP). This study established, detected, and analyzed an OA-induced steatosis model in LMH cells, which provides a stable model and detection method for the study of poultry steatosis-related diseases.

Single Fluorescent Probe for Zero-Crosstalk Discrimination of Lipid Droplets and the Endoplasmic Reticulum Based on Reversible Cyclization Reaction.

The interactions between different organelles are ubiquitous and crucial for life activities. Thus, development of a single fluorescent probe enabling the simultaneous two-color visualization of two organelles is of great significance for the study of organelle interplay. Herein, using the reversible ring-opening/closing reactions of rhodamine dyes, we have fabricated a robust fluorescent probe to distinguish lipid droplets (LDs) and the endoplasmic reticulum (ER) in dual-emission channels with negligible crosstalk. The probe 6'-(diethylamino)-4'-((7-(diethylamino)-2-oxo-2H-chromen-3-yl)methylene)-1',2',3',4'-tetrahydro-3H-spiro[isobenzofuran-1,9'-xanthen]-3-one, which was sensitive to the changes in the water content in the organism, displayed strong green fluorescence in the hydrophobic LDs from its ring-closed form, while it existed in a ring-opened form in the ER to illuminate a strong near-infrared emission. Importantly, the spectral difference was up to 320 nm, and thus the crosstalk between two channels was negligible. With the unique probe, the lipid accumulation in cells treated with different concentrations of oleic acid, cholesterol, and stearic acid has been successfully observed. The changes of LDs and the ER in living cells stimulated by temperature changes and hypoxia stimulation have also been revealed. Meanwhile, the different sizes and distribution of LDs and the ER in various tissues were also studied using the robust probe. This work provides a new approach to the design of dual-emissive probes and contributes to a significant molecular tool to promote the study of organelle interactions.

Oleic acid, independent of insulin, promotes differentiation of goat primary preadipocytes

Context Oleic acid together with insulin is widely used to induce preadipocyte differentiation in humans and mammals, and is also used alone in chicken preadipocytes from abdominal adipose tissue. However, it is not clear whether oleic acid alone promotes goat primary intramuscular preadipocyte differentiation. Aims The aim of the present study was to identify the role of oleic acid in regulating primary preadipocyte differentiation in goats. Methods Three healthy, 7-day-old Jianzhou goats were randomly selected. After slaughter, the longissimus dorsi tissues were collected from each goat under sterile procedures and mixed equally. The primary preadipocytes were then prepared using collagenase type I digestion, and treated with 5 mg/L insulin or different concentrations of oleic acid, including 0 μM, 50 μM, 100 μM, 150 μM and 300 μM. The results were determined using microscopy and Oil Red O staining. The expression of genes related to preadipocyte differentiation were determined by real-time fluorescence quantitative polymerase chain reaction. Results Lower concentrations of oleic acid (50 μM, 100 μM and 150 μM) did not affect the cell morphology and cell growth, whereas 300 μM oleic acid led to severe cytotoxicity compared with the control (0 μM). The treatment of oleic acid (100 μM) enhanced cellular accumulation and lipid droplets deposition significantly, which was not affected by supplementary insulin. In addition, insulin alone treatment did not alter cellular adipogenesis in goat intramuscular preadipocytes. Treatment with oleic acid significantly increased the expression of peroxisome proliferator-activated receptor gamma, CCAAT enhancer-binding protein alpha and fatty acid binding protein 4, and decreased the expression of lipoprotein esterase on Day 2 after cell differentiation, all of which decreased continually on Day 4 and Day 6. Expression of all genes increased significantly on Day 8 after oleic acid treatment in goat intramuscular preadipocytes. Conclusion The results underscore the role of oleic acid independent of insulin in promoting intramuscular preadipocytes in goats, and probably via the control of peroxisome proliferator-activated receptor gamma and CCAAT enhancer-binding protein alpha. Implications These data provide insight into the mechanism underlying preadipocyte differentiation.

Effect of exogenous lipids on cryotolerance of Atlantic salmon (Salmo salar) spermatozoa

The development of semen cryopreservation strategies is necessary to improve the semen storage technologies of species of great commercial interest for aquaculture. Recent studies demonstrate that lipids play an important role in the fertility and cryotolerance of fish gametes. This study investigated the effect of exogenous lipids in the freezing medium on the post-thaw functional parameters of Salmo salar spermatozoa. Semen samples (n = 12) were incubated in standard extender supplemented with different concentrations of oleic acid (OA, C18:1n9), linoleic acid (LA, C18:2n6), arachidonic acid (ARA, C20:4n6) and cholesterol-loaded cyclodextrin (CLC). Post-thaw motility, membrane integrity, mitochondrial membrane potential (ΔΨm), superoxide anion (O2•-) and fertility rates were analyzed. The results revealed that the semen incubated with 0.003 mmol/L OA increased the motility (~7%) and ΔΨm (~2%) (P < 0.05), but membrane integrity and fertility were not increased. The addition of 0.003 mmol/L LA increased the motility (~4%) and all LA extenders increased the ΔΨm (P < 0.05); however, LA increased the O2•- levels and decreased the membrane integrity and fertility (P < 0.05). Semen incubated with ARA improved sperm motility (~5%), membrane integrity (~10.5%) and fertility rates (~11%) (P < 0.05). The maximum improvement in post-thaw sperm functionality was observed by adding 0.003 mmol/L ARA. In contrast, sperm quality parameters and fertility were decreased by the CLC addition (P < 0.05). This study showed that ARA could be considered as an additive for semen cryopreservation and could be relevant in the reproductive process and reproductive management of Salmo salar.

Comparison of different carrier-compounds and varying concentrations of oleic acid on freezing tolerance of ram spermatozoa in tris-citric acid-egg yolk plasma semen diluent

The current study was conducted to determine the optimal concentration carrier-compound for oleic acid (OA) among dimethyl sulfoxide (DMSO), liposome and β-cyclodextrin on ram spermatozoa cryosurvival. The preliminary experiment was designed to ascertain the optimal concentration of egg yolk plasma. In Experiment 1, semen was placed in a diluent containing different concentrations of OA dissolved in DMSO (0.125, 0.25, 0.50, 1, 2, 4 and 8 mM). In Experiments 2 and 3, effects of liposome loaded-OA and β-cyclodextrin-OA complexes (0.25, 0.50, 1 and 2 mM) on semen cryopreservation were evaluated. In Experiment 4, optimal concentrations of OA were determined, based on results from previous experiments. Spermatozoa viability, kinematics, plasma membrane integrity, malondialdehyde, superoxide dismutase activity and total antioxidant status of samples were evaluated. Results indicated varying concentrations of OA had different effects on sperm kinematics, viability and membrane functionality after freezing/thawing (P < 0.05). In addition, inclusion of OA in liposomes or combinations with β-cyclodextrin resulted in greater values for spermatozoa motion variables compared with DMSO dissolved-OA (P < 0.05). Inclusions of OA at 0.25 and 0.50 mM led to a reduction in amounts of lipid peroxidation when there was inclusion of liposome and β-cyclodextrin as carrier-compounds (P < 0.05). Activity of SOD was similar with inclusion of different concentrations of OA or carrier-compounds, but total antioxidant capacity was affected by OA concentration and carrier-compound type (P < 0.05). The results highlight the importance of carrier-compound type and concentrations of OA on ram spermatozoa during cryopreservation.

Insights into the ameliorative effect of oleic acid in rejuvenating phenylhydrazine induced oxidative stress mediated morpho-functionally dismantled erythrocytes

Phenylhydrazine (PHZ), an intermediate in the synthesis of fine chemicals is toxic for human health and environment. Despite of having severe detrimental effects on different physiological systems, exposure of erythrocytes to PHZ cause destruction of haemoglobin and membrane proteins leading to iron release and complete haemolysis of red blood cells (RBC). Involvement of oxidative stress behind such action triggers the urge for searching a potent antioxidant. The benefits of consuming olive oil is attributed to its 75% oleic acid (OA) content in average. Olive oil is the basic component of Mediterranean diet. Hence, OA has been chosen in our present in vitro study to explore its efficacy against PHZ (1 mM) induced alterations in erythrocytes. Four different concentrations of OA (0.01 nM, 0.02 nM, 0.04 nM and 0.06 nM) were primarily experimented with, among which 0.06 nM OA has shown to give maximal protection. This study demonstrates the capability of OA in preserving the morphology, intracellular antioxidant status and the activities of metabolic enzymes of RBCs that have been diminished by PHZ, through its antioxidant mechanisms. The results of the present study firmly establish OA as a promising antioxidant for conserving the health of erythrocyte from PHZ toxicity which indicate toward future possible use of OA either singly or in combination with other dietary components for protection of erythrocytes against PHZ induced toxic cellular changes.

Formulation and Evaluation of Transdermal Patches Containing Glimipiride

The purpose of this research was to develop a matrix-type transdermal therapeutic system containing drug Glimepride with different ratios of hydrophilic and hydrophobic polymeric systems by the solvent evaporation technique. Different concentrations of oleic acid and isopropyle myristate were used to enhance the transdermal permeation of glimipride. Matrix type transdermal patches prepared by using different ratio of Eudragit RS100, HPMC100M, by using solvent evaporation techniques. All the prepared formulation were subjected to evaluation studies i.e., weight variation, thickness, drug content, moisture content, moisture uptake, flatness and in-vitro drug release. The physicochemical compatibility of the drug and the polymers studied by differential scanning calorimetry and infrared spectroscopy suggested absence of any incompatibility. Compatibility study between drug and polymer can be done by FTIR. From the all formulation batch F3 was optimized formula. Shows linear zero order release for 24 hrs with cumulative % drug diffusion of 88.34% from 4cm2 patches. It is concluded that concentration of polymer (HPMC100M) when increases into primary layer, then In-vitro diffusion rate also increases and concentration of Eudragit Rs100 when increases, the drug diffusion decreases. It provides better controlled drug release for patch.

Exogenous hydrogen sulfide mitigates NLRP3 inflammasome-mediated inflammation through promoting autophagy via the AMPK-mTOR pathway.

ABSTRACTThe aim of this study was to investigate whether exogenous hydrogen sulfide (H2S) could mitigate NLRP3 inflammasome-mediated inflammation through promoting autophagy via the AMPK-mTOR pathway in L02 cells. L02 cells were stimulated with different concentrations of oleic acid (OA), then cell viability and the protein expression of NLRP3 and pro-caspase-1 were detected by MTT and western blot, respectively, to determine appropriate OA concentration in this study. The cells were divided into four groups: the cells in the control group were cultured with RPMI-1640 for 24.5 h; the cells in the OA group were cultured with RPMI-1640 for 0.5 h, then were stimulated with 1.2 mmol/l OA for 24 h; the cells in the NaHS+OA group were pretreated with sodium hydrogen sulfide (NaHS, a donor of H2S) for 0.5 h before exposure to OA for 24 h; and the cells in the NaHS group were treated with NaHS 0.5 h, then were cultured with RPMI-1640 for 24 h. Subsequently, the cells in every group were collected and the protein expression of NLRP3, procaspase-1, cleaved caspase-1, P62, LC3, Beclin1, T-AMPK, P-AMPK, T-mTOR, P-mTOR and the level of IL-1β were detected by western blot and ElISA, respectively. Exogenous H2S reduced the level of NLRP3, caspase-1, P62, IL-1β and the ratio of P-mTOR/T-mTOR induced by OA and increased the ratio of LC3 II/I and the protein expression of Beclin1 suppressed by OA. This study demonstrates for the first time that H2S might suppress NLRP3 inflammasome-mediated inflammation induced by OA through promoting autophagy via the AMPK-mTOR pathway. It provides a theoretical basis for the further study of the anti-inflammatory mechanism of H2S.

The differentiation of preadipocytes and gene expression related to adipogenesis in ducks (Anas platyrhynchos).

Meat quality is closely related to adipose tissues in ducks, and adipogenesis is controlled by a complex network of transcription factors tightly acting at different stages of differentiation especially in ducks. The aim of this study was to establish the preadipocyte in vitro culture system and understand the biological characteristics of expansion of duck adipocyte tissue at the cellular and molecular level. We isolated pre-adipocytes from the subcutaneous fat of three breeds of duck and differentiated them into mature adipocytes using a mixture of insulin, rosiglitazone, dexamethasone, 3-isobutyl-1-methylxanthine, and oleic acid over 0,2, 4, 6, and 8 days. Successful differentiation was confirmed from the development of lipid droplets and their response to Oil Red O, and increasing numbers of lipid droplets were stained red over time. The expression of key marker genes, including peroxisome proliferator activated receptor γ (PPARγ), CCAAT/enhancer binding protein-α (C/EBPα), adipocyte fatty acid binding protein 4 (FABP4), and fatty acid synthetase (FAS), gradually increased during pre-adipocyte differentiation. Furthermore, it was verified by interference experiments that the knockdown of PPARγ directly reduced lipid production. Meanwhile we analyzed the role of unsaturated fatty acids in the production of poultry fat using different concentrations of oleic acid and found that lipid droplet deposition was highest when the concentration of oleic acid was 300 μM. We also compared the level of differentiated pre-adipocytes that were isolated from Jianchang ducks (fatty-meat duck), Cherry Valley ducks (lean-meat duck) and White-crested ducks (egg-producing duck). The proliferation and differentiation rate of pre-adipocytes derived from Jianchang ducks was higher than that of White-crested ducks. These results provide the foundation for further research into waterfowl adipogenesis.

Upregulated 14‑3‑3β aggravates restenosis by promoting cell migration following vascular injury in diabetic rats with elevated levels of free fatty acids.

Mono‑unsaturated free fatty acids (FFAs) can serve as a predictive indicator of vascular restenosis following interventional therapy, particularly in individuals with high‑fat diet‑induced type 2 diabetes. However, the pathogenic mechanism remains to be fully elucidated. In the present study, the levels of tyrosine 3‑monooxygenase/tryptophan 5‑monooxygenase activation protein β (YWHAB; also known as 14‑3‑3β), in vascular smooth muscle cells (VSMCs) treated with different concentrations of oleic acid (OA) were examined by reverse transcription‑quantitative polymerase chain reaction and western blot analyses. The migration of VSMCs was examined using wound‑healing and Transwell migration assays. The protein distribution of B‑cell lymphoma2 (BCL‑2)‑associated death promoter (BAD) in VSMCs treated with OA was examined by immunofluorescence and western blot analyses. In invivo experiments, the carotid artery morphology of rats in different groups was assessed at 14days post‑injury by non-invasive ultrasonographic imaging and confirmed by histological staining. The expression of YWHAB was upregulated by OA in a concentration‑dependent manner in VSMCs. In the invivo experiments, carotid stenosis was more serious among high‑FFA diabetic rats. However, silencing of YWHAB significantly alleviated carotid neointimal hyperplasia among the diabetic rats with elevated FFA levels. In addition, YWHAB silencing alleviated the migration of OA‑treated VSMCs and increased translocation of the BAD protein from the cytoplasm to the mitochondria. In conclusion, the results showed that FFA‑induced upregulation of YWHAB was involved in neointimal hyperplasia by enhancing the migration of VSMCs following carotid artery injury. The inhibition of YWHAB may serve as a novel potential pharmacological target for preventing vascular restenosis following interventional therapy in diabetic individuals with high FFA levels.

The effect of oleic acid concentration on the optical, structural, and magnetic properties of cobalt oxide nanostructures prepared by ultrasound-assisted method

ABSTRACTCobalt oxide nanostructures have been prepared using ultrasound waves by adding different concentrations of oleic acid as a capping agent. Cobalt oxide nanostructures were characterized using different techniques such as scanning electron microscopy, vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), differential thermal analysis (DTA), X-ray diffraction (XRD), UV–Vis, and FT-IR spectroscopy. The XRD patterns shows formation of pure cobalt oxide compounds in cubic structure. UV–Vis spectroscopy showed that by increasing the concentration of capping agent, the wavelength of absorption edge of the samples shifted toward blue region of the spectrum. The obtained results from VSM, indicated that the variation of magnetic susceptibility increased or decreased with concentration of oleic acid.

Mechanisms of highly stabilized ex-situ oleic acid-modified iron oxide nanoparticles functionalized with 4-pentynoic acid

In this paper, the main objective is to successfully functionalize 4-pentynoic acid on iron oxide nanoparticles (NPs) which arises second objective; to ex-situ modify different concentrations of oleic acid on the NPs. A new understanding has been achieved as to how the concentrations of oleic acid prior ex-situ modification, play a major role in the successful functionalization of 4-pentynoic acid on the NPs. The functionalization proposed is a potential alternative route of creating an acid anhydride from two carboxylic acids without the use of dehydrating agent. Unmodified NPs were synthesized by co-precipitation method and were altered to pH 12 using NH4OH to promote dispersity right before ex-situ modification with oleic acid (0.2–0.8 wt % oleic acid to iron oxide) and subsequent 4-pentynoic acid (1.63 × 10−3 mol) functionalization. Characterizations were conducted by X-ray-diffraction (XRD), Transmission Electron Microscopy (TEM), Thermogravimetric and Differential Thermal analysis (TGA-DTA), Fourier transform infrared spectroscopy (FTIR), proton nucleic magnetic resonance (NMR) and Zetasizer. A monolayer oleic acid is produced for ex-situ modification of 0.2 wt % oleic acid to iron oxide. Whereas the higher concentrations of oleic acid ex-situ modifications generate bilayer oleic acid-modified iron oxide NPs to which, functionalization of 4-pentynoic acid is only successfully performed. The samples pose highly stabilized dispersions at pH 12 varying between -42 and -75 mV, whereas the mean hydrodynamic particle size distributions are achieved at approximately 35–48 nm. Mechanisms of ex-situ modifications of different oleic acid concentrations and functionalization of 4-pentynoic acid on the iron oxide NPs at pH 12 and 333.15 K are also proposed.

Effects of three Wenyang Jianpi Tang on cell proliferation and apoptosis of nonalcoholic fatty liver cells

To investigate the effects of Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang on the cell proliferation and apoptosis of nonalcoholic fatty liver cells through the nonalcoholic fatty liver cell model established by inducing L02 cells with oleic acid. Different concentrations of oleic acid were added into L02 cells to induce the nonalcoholic fatty liver cell model. Oil red O staining was used to observe fatty droplets of fatty liver cells. Automatic biochemical analyzer was used to detect the levels of aspartic transaminase(AST), alanine aminotransferase(ALT), total cholesterol(TC), and triglyceride(TG) in the cell supernatants. There were five groups, namely normal group, model group, model and Sijunzi Tang group, model and Lizhong Tang group, and model and Fuzi Lizhong Tang group. The cell proliferation and apoptosis of the five groups were detected by MTT colorimetry test and flow cytometer. The expressions of PCNA, cleaved caspase-3, cleaved caspase-8, cleaved caspase-9, Bax and Bcl-2 proteins of the five groups were detected by Western blot. The oil red O staining results showed that the optimum concentration of oleic acid that was used to induce nonalcoholic fatty liver cell models was 80 mg•L-1. The levels of AST, ALT, TC and TG in the nonalcoholic fatty liver cell supernatants were higher than that in normal liver cell supernatants(P<0.01). MTT colorimetry test and flow cytometer results showed that all of Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang could effectively promote the cell proliferation, and inhibit the cellular apoptosis of nonalcoholic fatty liver cells(P<0.01). And Fuzi Lizhong Tang showed the best effect. Western blot results showed that Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang could down-regulate the expressions of cleaved caspase-3, cleaved caspase-8, cleaved caspase-9 and Bax proteins, and up-regulate the expressions of PCNA and Bcl-2 proteins of nonalcoholic fatty liver cells. And Fuzi Lizhong Tang showed the best effect. In conclusion, all of Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang could effectively promote the cell proliferation, and inhibit the cellular apoptosis of nonalcoholic fatty liver cells. And Fuzi Lizhong Tang showed the best effect. The pharmacodynamic mechanism may be related to the expressions of key factors in pathways related with proliferation and apoptosis mediated by the three decoctions.

An exhaustive review based on the formulation and evaluation methods behind the development of transdermal drug delivery systems

Transdermal drug delivery systems (TDDS) are dosage forms involves drug transport to viable epidermal and or dermal tissues of the skin for local therapeutic effect while a main function of drug is transported into the systemic blood circulation. The purpose of this research was to develop a matrix-type transdermal therapeutic system containing drug diclofenac with different ratios of hydrophilic (hydroxyl propyl cellulose) and hydrophobic (ethyl cellulose) polymeric systems polymeric systems by the solvent evaporation technique and by using Glycerol as plasticizer. Different concentrations of oleic acid and isopropyl myristate were used to enhance the transdermal permeation of Diclofenac. To improve characters of transdermal drug delivery system (TDDS) was emerged, which will improve the therapeutic efficacy and safety of drugs by specific sites within the body, thereby reducing both the size and number of doses. The present article reviews the selection of drug candidates and polymers suitable to be formulated as transdermal system, advantages, disadvantages of formulation design and the methods of evaluation. In this review article the various aspects of pharmaceutical transdermal drug delivery system where compiled together and the target audience are specifically the M Pharm and B Pharm students so that their knowledge towards the subject concern can be enhanced and also at the same time can be motivated towards the publications.

Investigation of Fucoidan-Oleic Acid Conjugate for Delivery of Curcumin and Paclitaxel.

Nanoparticles for a specific delivery are likely to be designed for cancer therapeutic effectiveness and improvement. In this study, a fucoidan-oleic acid conjugate was prepared and investigated in terms of loading capacity for poorly water-soluble anti-cancer drugs to maximize effectiveness of the treatment. Fucoidan was used as a hydrophilic portion of an amphiphilic structure for improving cancer therapeutic effects. Paclitaxel and curcumin were chosen as other model drugs loaded in the conjugates. The results showed that self-assembled nanoparticles with different sizes and morphologies could be prepared with two different concentrations of oleic acid as hydrophobic portion. Moreover, loading efficiency and release patterns of these drugs were mainly dependent on the hydrophobic interaction between drugs and oleic acid. It was also revealed that fucoidan and curcumin were released higher at pH 4.5 than at the physiological condition (pH 7.4), thus, facilitating the delivery and maximizing effects of the anticancer agents on cancer cells. On the contrary, paclitaxel from fucoidan nanoparticles was released faster at pH 7.4. The exploration of fucoidan-oleic acid conjugate could be considered as promising nanomedicines for cancer therapeutics.

Establishment of a hepatocyte steatosis model using Chang liver cells

The objective of this study was to explore the experimental conditions for hepatocellular steatosis models of Chang liver cells induced by oleic acid (OA). For that, Chang liver cells were induced by different concentrations of OA for different periods. The MTT assay was used to detect hepatic cell activity, the Oil Red O staining was used to observe intracellular lipid droplets accumulation, and the glycerol phosphate oxidase method was used to detect the triglyceride (TG) content in the Chang liver cell. The hepatocellular steatosis models of Chang liver cell were established successfully by inducing with 0.2 mM OA for 24h. TG content in model cells was 379.98 ± 23.19 mg/g, which is significantly different from control cells (185.03 ± 12.68 mg/g; P < 0.01). These were considered proper conditions for establishing hepatocellular steatosis models of Chang liver cells, producing a reliable model for nonalcoholic fatty liver disease research.

Formulation, optimization, and evaluation of a transdermal patch of heparin sodium.

The purpose of this research was to develop a matrix-type transdermal therapeutic system containing drug heparin sodium with different ratios of hydrophilic polymeric systems by the solvent evaporation technique by using 30% (w/w) of PEG 400 LR to the dry polymer weight, incorporated as plasticizer. Different concentrations of oleic acid and isopropyl myristate were used to enhance the transdermal permeation of heparin sodium. The physicochemical compatibility of the drug and the polymers studied by differential scanning calorimetry and infrared spectroscopy suggested absence of any incompatibility. Formulated transdermal films were physically evaluated with regard to thickness, weight variation, drug content, flatness, tensile strength, folding endurance, percentage of moisture content and water vapour transmission rate. All prepared formulations indicated good physical stability. In-vitro permeation studies of formulations were performed by using diffusion cell apparatus. Formulation prepared with hydrophilic polymer containing permeation enhancer showed best in-vitro skin permeation through Wistar albino rat skin as compared to all other formulations. Formulation F9 showed highest flux among all the formulations and 1.369-fold enhancements in drug permeation. These results indicate that the formulation containing 10% of oleic acid with 10% isopropyl myristate give better penetration of heparin sodium through rat skin.

Partitioning of Oleic Acid into Phosphatidylcholine Membranes Is Amplified by Strain

Partitioning of fatty acids into phospholipid membranes is studied on giant unilamellar vesicles (GUVs) utilizing phase-contrast microscopy. With use of a micropipet, an individual GUV is transferred from a vesicle suspension in a mixed glucose/sucrose solution into an isomolar glycerol solution with a small amount of oleic acid added. Oleic acid molecules intercalate into the phospholipid membrane and thus increase the membrane area, while glycerol permeates into the vesicle interior and thus via osmotic inflation causes an increase of the vesicle volume. The conditions are chosen at which a vesicle swells as a sphere. At sufficiently low oleic acid concentrations, when the critical membrane strain is reached, the membrane bursts and part of vesicle content is ejected, upon which the membrane reseals and the swelling commences again. The radius of the vesicle before and after the burst is determined at different concentrations of oleic acid in suspension. The results of our experiments show that the oleic acid partitioning increases when the membrane strain is increased. The observed behavior is interpreted on the basis of a tension-dependent intercalation of oleic acid into the membrane.

Electrokinetic Behavior of Fluorite

The electrokinetic behavior of fluorite mineral was studied under various partical sizes and different concentrations of oleic acid at constant pH. The particle size has been reduced with an increase in activation time. The surface energies of milled fluorite minerals were calculated theoretically and experimentally. The zeta potential of the fluorite/water system has shifted to lower side with an increase in particle size. The isoelectric point (iep) of fluorite minerals has been shifted to lower side with increase in oleic acid concentration. This indicates the chemisorbed oleate formation on fluorite. A sharp decrease in zeta potential in the pH range of 6.5–8.4 and the decrease in calculated free energy of adsorption shows the formation of calcium dioleate precipitate on fluorite.

Oleic acid decreases the expression of a cholesterol transport-related protein (NPC1L1) by the induction of endoplasmic reticulum stress in CaCo-2 cells

The reported data indicate that oleic acid (OA) decreases cholesterol absorption. To explore the underlying mechanisms, the effects of OA on the expression of cholesterol transport-related proteins (NPC1L1, ABCG5/8, ACAT2, MTP) and the unfolded protein response (UPR) pathway were studied in CaCo-2 enterocytes by incubating CaCo-2 cells with taurocholate micelles or taurocholate micelles containing different concentrations of OA (0.25-1.0 mM). We show that OA effectively induces XBP1 mRNA splicing, a key component of the UPR signaling, and the expression of BiP and mature ATF6 proteins in a concentration-dependent manner, leading to the induction of endoplasmic reticulum (ER) stress and activation of the UPR. Interestingly, OA decreases NPC1L1 expression in a dose-dependent manner while it has no effects on ABCG5 and MTP mRNA level or SREBP-2, ABCG8, and ACAT2 protein level. In CaCo-2 cells treated with 1.0 mM OA, both the NPC1L1 mRNA level and the NPC1L1 protein expression in brush-border membrane fractions were decreased by 39% and 37%, respectively (P < 0.01). A dose of 1 mM dithiothreitol (DTT), a positive control for ER stress induction, also decreases NPC1L1 mRNA and protein expression by 27% and 23%, respectively (P < 0.05). Furthermore, 4-phenyl-butyric acid, an UPR inhibitor, blocks OA- and DTT-induced reduction on NPC1L1 mRNA and protein levels. The results suggest that OA down-regulates NPC1L1 mRNA and protein expression via the induction of the UPR, which may play an important role in reducing intestinal cholesterol absorption.