Carrier mediated transport of choline in rat lens

Choline accumulation was studied in rat lenses incubated in TC-199 medium containing radiolabeled choline. Choline entered the lens and was rapidly phosphorylated. Phosphorylcholine did not readily escape the lens and continued to accumulate throughout 24 hr of incubation. Accumulation of choline displayed saturation kinetics and this saturability appeared to be a property of transport rather than a reflection of the properties of choline kinase. Countertransport of labeled choline from lenses preloaded with radiolabeled choline indicates that choline transport in rat lens is carrier mediated. The existence of a choline carrier would also be consistent with the kinetic data. Ethanolamine competed for the choline carrier, however a component of ethanolamine uptake was non-saturable at concentrations of ethanolamine or choline up to 5 mm. Choline and ethanolamine appeared to be phosphorylated by separate kinases in lens.     

Comparison of Foaming Properties Between the Shirasu Porous Glass Membrane Device and Tessari’s Three-way Stopcock Technique for Polidocanol and Ethanolamine Oleate Foam Production: A Benchtop Study

PurposeTo compare the characteristics of polidocanol (POL) and ethanolamine oleate (EO) sclerosing foams produced by a Shirasu porous glass membrane (SPGM) device with those made using a 3-way stopcock (3WSC).Materials and MethodsFoam half-life times were measured in an ex-vivo benchtop study. Computed tomography (CT) images of each foam were obtained over the time course, and a CT texture analysis was conducted. The bubble size in each foam was measured by an optical microscope.ResultsMedian foam half-life times were longer in the SPGM group than in the 3WSC group (POL: 198 vs 166 s, P = .02; EO: 640 vs 391 s, P < .01). In the CT texture analysis, median standard deviation (SD) and entropy (randomness) were lower, and median energy (uniformity) and gray-level cooccurrence matrix (GLCM) homogeneity were higher in the SPGM group than in the 3WSC group (POL SD: at 30 s and 50–300 s; POL entropy: at 0–60 s; EO SD: at 0–600 s; EO entropy: at 0–460 s; POL energy: at 0–40 s; POL GLCM homogeneity: at 0–250 s; EO energy: at 0–360 s; EO GLCM homogeneity: at 0–480 s; all P < .05). Median bubble diameters in the SPGM group and in the 3WSC group were 69 and 83 μm (P < .01), respectively, in the POL foam; and 36 and 36 μm (P = .45), respectively, in the EO foam.ConclusionsPOL and EO foams had greater uniformity and longer foam half-life time when prepared with an SPGM device than with a 3WSC.     

化学促渗剂与负极性驻极体促进5-氟尿嘧啶体外透过大鼠增生性瘢痕和背部皮肤的比较

目的 比较化学促渗剂和负极性驻极体对5-氟尿嘧啶（5-FU）体外经增生性瘢痕皮肤的促渗作用,为驻极体5-FU缓控释贴剂的制备奠定基础。方法 通过Franz扩散池和高效液相色谱仪,研究1%氮酮、10%油酸乙酯、-1 000 V驻极体、-1 500 V驻极体和-2 000 V驻极体作用后5-FU的体外经大鼠瘢痕皮肤或背部皮肤的透皮规律。结果 （1）1%氮酮和10%油酸乙酯均可促进5-FU经大鼠瘢痕皮肤的渗透,且10%油酸乙酯的促渗效果优于1%氮酮。（2）化学促渗剂作用下的5-FU经大鼠瘢痕皮肤和背部皮肤的体外渗透规律相似,但是5-FU经瘢痕皮肤的累积透皮量少于经背部皮肤的累积透皮量。（3）负极性驻极体对5-FU均具有良好的促渗作用,促渗效果的优劣顺序依次为：-2 000 V驻极体、-1 500 V驻极体、-1 000 V驻极体。同样,负极性驻极体作用下5-FU经大鼠瘢痕皮肤的累积透过量少于经背部皮肤的累积透皮量。结论 化学促渗剂和负极性驻极体均能促进5-FU的经皮渗透。其中,10%油酸乙酯和-2 000 V驻极体对5-FU的促渗效果最佳,可用于驻极体5-FU缓控释贴剂的制备。     

Focal differences in lipid metabolism of the young pig aorta : Part 2. Synthesis from [2-C]ethanolamine and [1,2-C]choline

The ability of normal young pig aortic tissue to synthesize phospholipids from [2-¹⁴C]ethanolamine and [1,2-¹⁴C]choline, in vitro, has been examined in areas of focal Evans Blue accumulation (blue areas) and adjacent areas of no dye accumulation (white areas).

Incorporation of [2-¹⁴C]ethanolamine into total lipid was linear for 3 h of incubation in both blue and white areas. At 3 h, ethanolamine incorporation into phosphatidyl ethanolamine was significantly less in blue than in white areas.

[1,2-¹⁴C]Choline incorporation into total lipid was linear for 3 h of incubation in blue areas but not in white areas. At 30 min, choline incorporation into phosphatidyl choline was significantly less in blue than in white areas; at 1 h choline incorporation into phosphatidyl choline was similar in blue and white areas, while after 3 h of incubation incorporation was significantly greater in blue than in white areas.

With both [2-¹⁴C]ethanolamine and [1,2-¹⁴C]choline, the percentage distribution of label among individual phospholipids was similar in blue and white areas.

Phospholipid content of blue and white areas was similar.

The results presented demonstrate further focal metabolic differences within the same geographical region of the normal young pig aorta.     

Adverse effect of obesity on red cell membrane arachidonic and docosahexaenoic acids in gestational diabetes

Aims/hypothesis Gestational diabetes is a metabolic disorder affecting 2–5% of women and is a predictor of obesity, Type 2 diabetes mellitus and cardiovascular disease. Insulin resistance, a characteristic of gestational diabetes and obesity, is correlated with the fatty acids profile of the red cell and skeletal muscle membranes. We investigated the plasma and red cell fatty acid status of gestational diabetes. The effect of obesity on membrane fatty acids was also examined.Methods Fasting blood obtained at diagnosis was analysed for the fatty acids in plasma choline phosphoglycerides and red cell choline and ethanolamine phosphoglycerides.Results There were reductions in arachidonic acid (controls 10.74±2.35 vs gestational diabetes 8.35±3.49, p<0.01) and docosahexaenoic acid (controls 6.31±2.67 vs gestational diabetes 3.25±2.00, p<0.0001) in the red cell choline phosphoglycerides in gestational diabetes. A similar pattern was found in the ethanolamine phosphoglycerides. Moreover, the arachidonic and docosahexaenoic acids depletion in the red cell choline phosphoglycerides was much greater in overweight/obese gestational diabetes (arachidonic acid=7.49±3.37, docosahexaenoic acid=2.98±2.18, p<0.01) compared with lean gestational diabetes (arachidonic acid=10.03±2.74, docosahexaenoic acid=4.18±1.42).Conclusion/interpretation Apparently normal plasma choline phosphoglycerides fatty acids profile in the gestational diabetic women suggested that membrane lipid abnormality is associated specifically with perturbation in the membrane. The fact that the lipid abnormality is more pronounced in the outer leaflet of the membrane where most of receptor binding and enzyme activities take place might provide an explanation for the increased insulin resistance in gestational diabetes and obesity.Abbreviations AA arachidonic acid - CPG choline phosphoglycerides - DHA docosahexaenoic acid - EPG ethanolamine phosphoglycerides - FAME fatty acid methyl esters - GDM gestational diabetes mellitus     

Sclerotherapy for Simple Cysts with Use of Ethanolamine Oleate: Preliminary Experience

We evaluated the efficacy of ethanolamine oleate (EO) as a sclerosing agent for a symptomatic hepatic or renal cyst. Seven patients with symptomatic hepatic (n = 3) or renal cysts (n = 4) were treated by sclerotherapy with EO. The cyst size in the greater diameter ranged from 6 to 13 cm. The cyst was punctured under ultrasound guidance, and after all of the cyst’s content was aspirated, an iodized contrast agent was injected to check the absence of communication between the cyst and biliary tree, urinary tract, or vessels. Then, the solution of ethanolamine oleate–iopamidol mixture (EOI) of 10% of the volume of the cyst’s content was injected via catheter. After 30 min, the injected EOI was aspirated completely before catheter removal. A follow-up computed tomography scan was performed at 1 and 3 months after treatment. The volume of the cyst and its reduction rate was calculated. In addition, symptoms and complications were assessed. The volume of the cyst ranged from 64 to 636 ml (mean: 328 ml) before treatment. Three months after treatment, it ranged from 2 to 50 ml (mean: 15ml) and the reduction rate of the cyst’s volume was more than 90% on average. Symptoms caused by the cyst disappeared in all cases and no major complication was encountered. Although two patients had a low-grade fever after sclerotherapy, it was easily controlled. It is suggested that the sclerotherapy with EO might be a safe, effective, well-tolerated treatment for symptomatic hepatic or renal cysts.     

ANALYSIS OF PROGNOSTIC FACTORS IN PATIENTS WITH GASTRIC VARICES AFTER ENDOSCOPIC TREATMENT

Background: The prognostic factors, including gastric variceal bleeding itself, in patients with gastric varices (GV) after endoscopic treatment remain unclear. The aim of this study was to analyze prognostic factors in patients with GV after endoscopic treatment as well as to evaluate safety and efficacy of our endoscopic treatment. Patients and Methods: This study enrolled 115 patients who underwent endoscopic treatment for GV between October 1988 and December 2003 using cyanoacrylate and 5% ethanolamine oleate. Successful hemostasis, recurrence rates, rebleeding rates, survival rates, complications and prognostic factors after the treatment were retrospectively reviewed. Results: Treatment sessions for GV were performed 3.4 ± 2.5 times. All cases, including 14 emergency cases, were treated successfully. The cumulative recurrence rates at 1, 3 and 5 years after the treatment were 7.0%, 15.6% and 20.0%, respectively, and the cumulative rebleeding rates at 1, 3 and 5 years were 3.5%, 8.7% and 14.8%, respectively. The overall survival rates were 78.3%, 63.7% and 51.5% at 1, 3 and 5 years, respectively. Grade B or C in Child–Pugh classification, emergency or elective cases, and association with hepatocellular carcinoma were identified as significant negative prognostic factors after endoscopic treatment by multivariate analysis. Although several complications were observed, there was no mortality. Conclusions: Grade B or C in Child–Pugh classification, emergency or elective situation, and association with hepatocellular carcinoma are negative prognostic factors after endoscopic treatment.     

Conjugated linoleic acid alters caveolae phospholipid fatty acid composition and decreases caveolin-1 expression in MCF-7 breast cancer cells

Conjugated linoleic acid (CLA) refers to a group of biologically active fatty acids that exhibit anticarcinogenic properties; however, the mechanism of action remains poorly understood. Caveolae are specialized plasma membrane structures that affect many facets of cancer cell function, including growth, cell signaling, and apoptosis. Therefore, one potential mechanism could be alteration of caveolae lipid composition and function. We hypothesized that CLA can alter the lipid microenvironment of caveolae and alter expression of the major caveolae-resident protein, caveolin-1. MCF-7 human breast cancer cells were treated with a vehicle control, linoleic acid (LA), or CLA for 3 days after which total cell lysate, plasma membrane, and caveolae membrane fractions were isolated. Our findings indicate that CLA readily incorporates into caveolae (Δ9cis,11trans-18:2 being the major isomer) and maybe preferentially enriched in specific phospholipid species. Furthermore, caveolin-1 localization to caveolae after treatment with CLA was decreased relative to either control- or LA-treated cells, without changes in total cellular levels of protein relative to vehicle-control treated cells. Taken together, our results suggest that further investigation of a potential therapeutic role for CLA in modulating caveolae function in breast cancer is merited.     

The cytoprotective effects of oleoylethanolamide in insulin-secreting cells do not require activation of GPR119

BACKGROUND AND PURPOSE

β-cells express a range of fatty acid-responsive G protein-coupled receptors, including GPR119, which regulates insulin secretion and is seen as a potential therapeutic target in type 2 diabetes. The long-chain unsaturated fatty acid derivative oleoylethanolamide (OEA) is an endogenous agonist of GPR119 and, under certain conditions, some long-chain unsaturated fatty acids can promote β-cell cytoprotection. It is not known, however, if OEA is cytoprotective in β-cells. The present study has examined this and determined whether GPR119 is involved.

METHODS

Clonal rat insulin-secreting cell lines, BRIN-BD11 or INS-1E, were exposed to fatty acids complexed with BSA. cAMP levels, insulin release and cell viability were measured. Protein expression was studied by Western blotting and receptor expression by RT-PCR.

KEY RESULTS

GPR119 was expressed in both BRIN-BD11 and INS-1E cells and OEA was cytoprotective in these cells. However, cytoprotection was not reproduced by any of a range of selective, synthetic ligands of GPR119. The cytoprotective response to OEA was lost during exposure to inhibitors of fatty acid amide hydrolase (FAAH) suggesting that OEA per se is not the cytoprotective species but that release of free oleate is required. Similar data were obtained with anandamide, which was cytoprotective only under conditions favouring release of free arachidonate.

CONCLUSIONS AND IMPLICATIONS

Activation of GPR119 is not required to mediate the cytoprotective actions of OEA in BRIN-BD11 or INS-1E cells. Rather, OEA is internalised and subjected to hydrolysis by FAAH to release free oleate, which then mediates the cytoprotection.