bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of prostatic secretion protein on uptake of androgen‐receptor complex in prostatic cell nuclei
Authors: Pousette ÅKe , Björk Per , Carlström Kjell , Forsgren Björn , Högberg Bertil , Gustafsson Jan‐Åke
Published: February 2007

Prostatic secretion protein (PSP) is a major component of rat prostatic cytosol, and this protein is also found in the prostatic fluid. Purified PSP was found to inhibit the nuclear uptake of the [3H]methyltrienolone‐receptor complex in vitro. Furthermore, purified PSP inhibited the binding of this androgen‐receptor complex to DNA‐cellulose. It is suggested that these effects of PSP may represent an intracellular control system regulating the concentration of PSP. Administration of estramustine, the dephosphorylated metabolite of the anti‐cancer drug estramustine phosphate (Estracyt®), to rats was found to decrease the weight of the prostate gland but to maintain the concentration of PSP, calculated as mg PSP/mg protein, at a constant level. In contrast, castration or administration of estradiol‐17β valerate decreased the weight of the prostate gland as well as the concentration of PSP. These findings indicate that the mechanism of action of estramustine is at least partially different from that of estradiol‐17β. Furthermore, it is suggested that estramustine may exert part of its action through its effects on the concentration of PSP.
Cell separation and characterization of epithelial cells from human benign prostatic hyperplasia
Authors: Oishi K. , Romijn J. C. , Schröder F. H.
Published: February 2007

Epithelial cells were isolated from human prostatic hyperplasia (BPH) after mechanical disruption of the tissue. The tissue was cut into small pieces, then mechanical pressure was applied. Stroma and epithelium were separated by a sequence of sedimentation steps. The recovery rate of epithelial cells was around 20 million cells per gram of tissue and more than 95% of the cells did exclude trypan blue. Epithelial cells can be identified by phase contrast microscopy and by the acid phosphatase content of the cells. In more than 95% of the cells the presence of acid phosphatase could be shown cytochemically with phosphorylcholine as a substrate. This finding indicates that the contamination with other cell types is very small. Histological study of the remaining stroma indicates that most of the epithelial cells are removed. Also, the acid phosphatase content of this fraction was found to be very low. The problem of obtaining large quantities of stromal cells in suspension has not yet been resolved. However, the technique described may be more suitable than others for the separate study of stroma and epithelium from BPH.
Effect of surgery and adjuvant chemotherapy on the R3327 MAT‐Ly Lu tumor
Authors: Kadmon Dov , Heston Warren D. W. , Fair William R.
Published: February 2007

The R3327 MAT‐Ly Lu is a prostate derived, anaplastic, hormone independent carcinoma. It spreads primarily to regional lymph nodes, followed by lung metastases. Combination therapy with surgery (tumor removal with or without regional lymphadenectomy) and chemotherapy (ICRF‐159) was more effective treatment than either one alone. Primary tumor excision plus lymphadenectomy appeared to reduce the number of pulmonary metastases.
Melanin‐like pigment in the human prostate
Authors: Seman Gabriel , Gallager H. Stephen , Johnson Douglas E.
Published: February 2007

Twenty surgical specimens of prostate [1 histologically normal, 8 with benign hyperplasia (BPH), and 11 with cancer (PCa)] were examined by histochemical staining methods for the presence of a melanin‐like pigment that we first observed in organ culture. Fontana‐Masson‐positive pigment was observed in epithelial cells of the normal specimen, of five BPH and of eight PCa. The distribution of pigment in BPH was unpredictable and patchy. The pigment was consistently absent in neoplastic epithelia. Silver‐positive stromal cells also were observed in a number of the specimens. The epithelial pigment reacted to histochemical stains in part like melanin, in part like lipofuscin. It probably represents an endogenous pigment similar to other types of noncutaneous melanins.
Densitometric and morphometric evaluation of growth in primary cultures of rat ventral prostate epithelial cells
Authors: Terracio Louis , Douglas William H. J.
Published: February 2007

This study describes a method for establishing primary cultures in 24‐well culture vessels and evaluating the effects of serum, hormones, and other factors on cell growth using densitometry. Primary cultures of rat ventral prostate epithelial cells were grown in 24‐well culture vessels containing F12K culture medium supplemented with various concentrations of the following substances: fetal bovine serum (FBS), horse serum (HS), testosterone (T), dihydrotestosterone (DHT), hydrocortisone (HC), zinc (Zn), transferrin (TR), cysteine (CYS), glutamine (GLT), selenium (SEL), and ascorbic acid (AC). The effect of each supplement on cell growth was evaluated on fixed and stained cultures using a photovoltaic cell densitometer designed to read the total culture surface of a 16‐mm well. Increasing concentrations of both HS and FBS resulted in an increase in cell growth. T, Zn, HC, TR, and AC each had a stimulatory effect on cell growth. CYS, GLT, and DHT had little effect on cell growth, while SEL was inhibitory to cell growth. This data compares favorably with that obtained by other methods, such as morphometric analysis and ornithine decarboxylase production. These results indicate that densitometry is a useful method for determining the effect of supplements on cell growth in primary culture.
Prostatic binding protein, polyamine, and dna synthesis in rat ventral prostate cells
Authors: McKeehan Wallace L. , Glass Howard A. , Rosser Mary P. , Adams Pamela S.
Published: February 2007

Prostatic binding protein (PBP), polyamine, and DNA synthesis were examined in primary cultures of rat ventral prostate cells. Soon after aggregates of prostate cells were placed in culture, PBP synthesis fell dramatically and DNA synthetic activity in the epithelial cells increased. The amount of polyamines that were labeled with [3H] from [3H]ornithine fell transiently, but rose again at or before the peak of DNA synthesis. Individual 3H‐labeled polyamines in cells and medium were dansylated and separated by thin‐layer chromatography. The ratio of [3H]Spermidine plus [3H]Spermine to [3H]Putrescine in the culture medium declined as DNA synthesis increased. Ornithine decarboxylase (ODC) activity fell dramatically along with PBP synthesis even as DNA synthesis and 3H‐labeled polyamines increased in the prostate‐cell cultures. These results support others that suggest that high ODC activity in prostate epithelial cells is a correlate of prostate epithelial cell function rather than proliferation. However, prostate epithelial cells retain the capacity to synthesize significant levels of polyamines from ornithine (especially Putrescine) during proliferation even when ODC activity is low.
Nuclear androgen receptor assay in biopsy‐size specimens of human prostatic tissue
Authors: Blankenstein M. A. , Bolt‐DeVries J. , Foekens J. A.
Published: February 2007

Nuclear androgen receptors in benign and malignant human prostatic tumors were estimated with a nuclear exchange assay to evaluate the applicability of the assay to biopsy‐size tissue samples. The mean nuclear androgen receptor content of six different prostate samples was not dependent on the amount of tissue used. In contrast, however, there was no significant correlation between the results obtained for individual prostates when large samples (500 mg) and samples weighing 100, 50 (r = 0.38, n = 14), and 25 mg were compared. This lack of correlation could not be attributed to variations in the assay nor to differences in the percentage of epithelium in the samples. There was no effect of the presence of molybdate on the estimated nuclear androgen receptor level. We concluded that androgen receptors are distributed nonhomogeneously over prostatic tissue and that androgen receptor assays on multiple biopsies are required to obtain a proper estimate of the true androgen receptor content of the tissue.
Effect of molybdate on androgen receptor levels in canine prostate
Authors: Naritoku Wesley Y. , Howard Edwin B. , Britt James O. , Markland Francis S.
Published: February 2007

A comparative study on the stabilizing effect of sodium molybdate on androgen receptors was performed using canine prostates. Prostates from intact male dogs of mixed breeds were run in parallel sucrose density gradient analyses, using buffer systems with or without molybdate. Prostates that were homogenized in a molybdate buffer showed a significant increase in androgen receptor content relative to those in a molybdate‐free system.
Age‐adjusted mortality rate and regional distribution for prostatic carcinoma in Italy between 1969 and 1978
Authors: Di Silverio F. , La Pera G. , Tenaglia R.
Published: February 2007

The age‐adjusted mortality rate for prostatic carcinoma in Italy between 1969 and 1978 was calculated, as was the regional distribution for this disease. An overall increase in mortality was found, but the increase of the age‐adjusted data was not statistically significant. The regional distribution of age‐adjusted mortality rate showed a difference between northern and southern Italy, even when errors that can affect these findings were taken into consideration. At present, however, the size of these errors is not known. Such factors should not, however, prevent development of useful information and indications, but they should not be overlooked in an analytical interpretation of the data.
Effect of inhibitors or RNA and protein synthesis on mitochondrial aspartate aminotransferase response to testosterone in rat ventral prostate
Authors: Franklin R. B. , Brandly R. L. , Costello L. C.
Published: February 2007

The prostate gland is unusual in that it has a high content of citric acid compared with other soft tissues. The mechanism of citrate accumulation in prostate is unknown. One possibility is that aspartate aminotransferase (AAT) could supply an extra Krebs cycle source of oxaloacetate for citrate formation. Since testosterone regulates citrate production and secretion and strong transaminase activity exists in prostate, a relationship between AAT and citrate production could exist if testosterone also regulates AAT activity. To investigate this possibility, animals were castrated and given testosterone. After a total castration period of 72 hours, animals were sacrificed and mitochondrial AAT activity determined. Results revealed that castration decreased AAT activity and testosterone replacement stimulated activity. Neither castration nor testosterone affected malate dehydrogenase (MDH) activity. Both actinomycin D and cycloheximide blocked the testosterone stimulation of AAT activity. These studies indicate that testosterone may regulate AAT activity in rat ventral prostate. Furthermore, regulation may occur through testosterone stimulation of specific RNA and protein synthesis.
Intravenous application of omega‐3 fatty acids in patients with active rheumatoid arthritis. The ORA‐1 trial. An open pilot study
Authors: Leeb Burkhard F. , Sautner Judith , Andel Ingrid , Rintelen Bernhard
Published: February 2007

The objective of this work was to assess the therapeutic efficacy and to lerability of intravenously applied n‐3‐PUFA in patients with active rheumatoid arthritis (RA). Thirty‐four patients with active RA [identified as having a DAS28 (disease activity score including a 28 joint count) >4.0] were enrolled into this 5‐wk open pilot study (one group design). From the time of screening (visit 0, or V0), background therapy had to remain unchanged. Patients received 2 mL/kg(=0.1–0.2 g fish oil/kg) fish oil emulsion intravenously on 7 consecutive days (Visit 1–Visit 2, or V1–V2) in addition to their background therapy. A decrease of the DAS28>0.6 at day 8 (Visit 2) was the primary efficacy measure. Moreover, the DAS28 at day 35 (Visit 3, or V3), the modified Health Assessment Questionnaire, the American College of Rheumatology (ACR) response criteria (V2, V3) and the Short Form‐36 (V3) were assessed. Thirty‐three patients completed the trial. The mean DAS28 at V1 was 5.45; at V2, 4.51 (P<.001 V1–V2) and at V3, 4.73 (P<.001 V1–V3; V2–V3, not significantly different). Of the 34 patients, 56% achieved a reduction of the DAS28>0.6 at V2 (mean 1.52); 27%>1.2. At V3, 41% of the patients showed a DAS28 reduction >0.6 (mean 1.06), and 36%>1.2. ACR 20 and 50% responses at V2 were seen in 29 and 12% of patients, respectively; at V3, the comparable values were 18 and 9%, respectively. Overall tolerability was excellent. Intravenous application of n‐3‐PUFA (as an add‐on therapy) was considerably well tolerated and led to improvement of the disease activity status in a reasonable number of RA patients. Future trials are warranted to answer whether the intravenous application of n‐3‐PUFA constitutes a therapeutic option in RA patients.
Astonishing diversity of natural surfactants: 7. Biologically active hemi‐ and monoterpenoid glycosides
Authors: Dembitsky Valery M.
Published: February 2007

This review article presents 90 hemi‐ and 188 monoterpenoid glycosides, isolated and identified from plants and microorganisms, that demonstrate different biological activities. These natural bioactive glycosides are good prospects for future chemical preparations from these compounds as antioxidants and as anticancer, antimicrobial, and antibacterial agents. These glycosidic compounds have been subdivided into several groups, including hemiterpenoids; acyclic, monocyclic, and bicyclic monoterpenoids; and iridoid monoterpenoids.
n‐3 polyunsaturated fatty acids endogenously synthesized in fat‐1 mice are enriched in the mammary gland
Authors: Ma David W. L. , Ngo Victoria , Huot Pedro S. P. , Kang Jing X.
Published: February 2007

In this study, we determined the phospholipid FA composition in the mammary gland of the transgenic Fat‐1 mouse. This is the first animal model developed that can endogenously synthesize n−3 PUFA. The synthesis of n−3 PUFA is achieved through the expression of the fat‐1 transgene encoding for an n−3 desaturase from Caenorhabditis elegans, which utilizes n−6 PUFA as substrate. Wild‐type and Fat‐1 female mice were terminated at 7 wk of age and the fifth mammary gland was removed. Lipids were extracted and phospholipids were separated by TLC and converted to FAME for analysis by GC. There was no significant change in total saturated, monounsaturated, and PUFA composition. However, there was a significant increase in total n−3 PUFA and a corresponding decrease in n−6 PUFA. The major n−3 PUFA that were enriched included 20:5n−3 and 22:6n−3. The n−6 PUFA that were reduced included 20:4n−6, 22:4n−6, and 22:5n−6. Overall, these findings demonstrate that female Fat‐1 mice have elevated levels of n−3 PUFA in the mammary gland. Moreover, the n−3 desaturase products are the same n−3 PUFA found in fish oil, which have been shown to have chemoprotective properties against breast cancer. Therefore, this newly developed mouse model may be highly useful for investigating molecular and cellular mechanisms by which n−3 PUFA prevents and inhibits breast cancer growth.
Dietary comparison of conjugated linolenic acid (9 cis, 11 trans, 13 trans) and α‐tocopherol effects on blood lipids and lipid peroxidation in alloxan‐induced diabetes mellitus in rats
Authors: Dhar P. , Bhattacharyya D. , Bhattacharyya D. K. , Ghosh S.
Published: February 2007

The present study investigated the dietary effect of conjugated linolenic acid (CLnA) on lipid profiles and lipid peroxidations in alloxan‐induced diabetes mellitus in rats. Diabetic rats were fed with 20% sunflower oil (diabetic control), sunflower oil supplemented with 0.5% CLnA, sunflower oil supplemented with 0.15% α‐tocopherol, and sunflower oil containing 0.25% CLnA+0.15% α‐tocopherol. The results demonstrated that 0.5% CLnA, 0.15% α‐tocopherol, and 0.25% CLnA+0.15% α‐tocopherol each on supplementation significantly lowered total cholesterol and non‐HDL‐cholesterol in comparison with the diabetic control group. The TAG level was significantly lowered in both the 0.15% α‐tocopherol and 0.25% CLnA+0.15% α‐tocopherol groups. LDL lipid peroxidation and erythrocyte membrane lipid peroxidation were reduced significantly in each of the experimental groups vs. the control group. The CLnA+α‐tocopherol diet induced a greater reduction in membrane lipid and liver lipid peroxidation than the α‐tocopherol diet alone. In conclusion, dietary CLnA exerts antioxidant activity as evidenced by reduced lipid peroxidation in chemically induced diabetes mellitus.
Lymphatic transport of a physical mixture of medium‐and long‐chain TAG in rats
Authors: Takeuchi Hiroyuki , Funabashi Jun , Ooyama Katsuhiko , Aoyama Toshiaki , Sugano Michihiro
Published: February 2007

Lymphatic transport of a mixture of medium‐chain TAG (MCT) and long‐chain TAG (LCT) was studied in lymph‐cannulated rats. Animals were administered a test emulsion containing either triolein, tricaprylin, or a 1∶1 mixture of triolein and tricaprylin, and the lymph was collected for 24 h. The lymphatic recovery rate of medium‐chain FA (MCFA) was significantly higher in rats given the TAG mixture than in those given MCT alone. The lymphatic recovery rate of long‐chain FA (LCFA) also was significantly higher in rats given the TAG mixture than in those given LCT alone. No TAG containing three MCFA (i.e., MCT) was detected, and 37.7% of TAG containing one or two MCFA was detected in the lymph TAG when rats were given the TAG mixture. These results indicate that lymphatic transport of MCFA and LCFA can be modified by the combination of MCT and LCT.
Effect of sucrose and saturated‐fat diets on mRNA levels of genes limiting muscle fatty acid and glucose supply in rats
Authors: Ferrer‐Martínez Andreu , Marotta Mario , Turini Marco , Macé Katherine , Gómèz‐Foix Anna M.
Published: February 2007

In this study, we examined whether the increased availability of lipids in blood resulting from two types of diet manipulation regulated metabolic gene expression in the skeletal muscle of rats. Feeding for 4 wk on an isocaloric‐sucrose or a hypercaloric‐fat diet increased plasma TAG in the fed condition by increments of 70 and 40%, respectively, and increased fasting insulinemia (approximately 3‐fold) compared with a starch diet. The fat diet impaired glucose tolerance and caused obesity, whereas sucrose‐fed rats maintained their normal weight. We analyzed the expression of genes that regulate the exogenous FA supply (LPL, FAT/CD36, FATP1), synthesis (ACC1), glucose (GLUT4, GLUT1, HK2, GRAT1, glycogen phosphorylase) or glycerol (glycerol kinase) provision, or substrate choice for oxidation (PDK4) in gastrocnemius and soleus muscles at the end of the glucose tolerance test. LPL, FAT/CD36, FATP1, PDK4, and GLUT4 mRNA as well as glycogen phosphorylase and glycerol kinase activity levels in both muscles were unchanged by the diets. Increased mRNA levels of GLUT1 (1.6‐ and 2.6‐fold, respectively) and GFAT1 (about 1.7‐fold) in gastrocnemius, and of ACC1 (about 1.5‐fold) in soleus, were found in both the sucrose and fat groups. In the fat group, HK2 mRNA was also higher (1.8‐fold) in the gastrocnemius. Both sucrose and saturated‐fat diets prompted hyperinsulinemia and hyperlipemia in rats. These metabolic disturbances did not alter the expression of LPL, FAT/CD36, FATP1, PDK4, and GLUT4 genes or glycogen phosphorylase and glycerol kinase activity levels in either analyzed muscle. Instead, they were linked to the coordinated upregulation in gastrocnemius of genes that govern glucose uptake and the hexosamine pathway, namely, GLUT1 and GFAT1, which might contribute to insulin resistance.
Monitoring monohydroperoxides in docosahexaenoic acid using high‐performance liquid chromatography
Authors: Lyberg Ann‐Marie , Adlerceutz Patrick
Published: February 2007

The oxidation of free DHA has been investigated with respect to monohydroperoxides and polyhydroperoxides, which were analyzed with a novel HPLC method. The temperature and physical system, i.e., bulk and liposome, were varied. We have also studied the effects of antioxidants such as α‐tocopherol, ascorbic acid, and juice from sea buckthorn on DHA. The HPLC method, which was performed isocratically, eluted eight peaks, each containing one or two isomers of monohydroperoxy‐DHA. This method showed that the double bond farthest from the carboxyl group was easily oxidized, as shown by the rapid increase in the amount of C20‐monohydroperoxy‐DHA, which always provided the largest contribution to the total amount of monohydroperoxides. The monohydroperoxy‐DHA containing the hydroperoxy group located on the double bond nearest the carboxyl group also was shown to incease considerably during an increase in the total amount of monohydroperoxides. This demonstrates that the double bonds located nearest and farthest from the carboxyl group were the most prome to hydroperoxide formation. DHA was more stable when stored in liposomes than as bulk. Addition of α‐tocopherol to the DHA‐containing liposomes reduced the oxidation of these double bonds. The antioxidant effect of α‐tocopherol was prolonged when combined with ascorbic acid, since α‐tocopherol was regenerated.
Lipase‐catalyzed esterification of 2‐monoricinolein for 1,2(2,3)‐diricinolein synthesis
Authors: Turner Charlotta , Wani Seiji , Wong Rosalind , Lin Jiann‐Tsyh , McKeon Thomas
Published: February 2007

The purpose of this investigation was to develop conditions for producing 2‐monoricinoleoyl DAG. We used lipase‐catalyzed hydrolysis of triricinolein to obtain 2‐monoricinolein and thereafter synthesized 1,2(2,3)‐diricinolein through esterification of 2‐monoricinolein, using ricinoleic acid as the acyl donor. Five different 1,3‐specific immobilized lipases were tested for the initial methanolysis reaction: Candida antarctica type B, Rhizomucor miehei, Rhizopus oryzae (ROL), Thermomyces lanuginosus, and Aspergillus niger. For the second esterification reaction, we investigated these five lipases plus Pseudomonas cepacia, Penicillium roquefortii, Candida rugosa, and Pseudomonas fluorescence. Toluene and diisopropyl ether (DIPE) were examined as reaction media at a water activity of 0.11. ROL in DIPE gave the highest yield of 2‐monoricinolein from triricinolein, 78% after 3 h of reaction. The isolated 2‐monoricinolein was esterified with ricinoleic acid for synthesis of 1,2(2,3)‐diricinolein. ROL in DIPE gave the highest yield of 1,2(2,3)‐diricinolein, 58% after 1 h of reaction, and NMR analysis showed that the purity was 97.2%. This methodology can used for synthesizing radiolabeled 1,2(2,3)‐diricinolein to study lipid biosynthesis in castor and other oilseeds.
A significant inverse relationship between concentrations of plasma homocysteine and phospholipid docosahexaenoic acid in healthy male subjects
Authors: Li Duo , Mann Neil J. , Sinclair Andrew J.
Published: February 2007

The aim of this study was to investigate the possibility of a relationship between plasma homocysteine (Hcy) and phospholipid FA (PUFA) in healthy Australian males. One hundred thirty six healthy male subjects aged 20–55 yr were recruited from the Melbourne metropolitan area. Each volunteer completed a semiquantitative food frequency questionnaire and gave a blood sample. Plasma Hcy concentrations were determined by an established HPLC method; the plasma phospholipid FA were determined by standard methods. Plasma Hcy concentration was significantly negatively correlated with plasma phospholipid concentration of the PUFA 20∶5n−3 (r=−0.226, P=0.009), 22∶5n−3 (r=−0.182, P=0.036), 22∶6n−3 (r=−0.286, P=0.001), total n−3 (r=−0.270, P=0.002) and the ratio n−3/n−6 PUFA (r=−0.265, P=0.002), and significantly positively correlated with 20∶4n−6 (r=0.180, P=0.037). In the partial correlation analysis, after controlling for serum vitamin B12 and folate concentration, plasma Hcy was significantly negatively correlated with the plasma phospholipid concentration of 22∶6n−3 (r=−0.205, P=0.019), total n−3 (r=−0.182, P=0.038) and the ratio n−3/n−6 PUFA (r=−0.174, P=0.048). Evidence indicates that an increased concentration of n−3 PUFA in tissues has a beneficial effect on cardiovascular health. Our findings provide further evidence that increased consumption of dietary n−3 PUFA increases the concentration of n−3 PUFA in plasma phospholipid, which is associated with a protective effect on cardiovascular diseases and lower plasma Hcy levels. The mechanism that might explain the association between plasma 22∶6n−3 and Hcy levels is not clear.
The real radical generator other than main‐product hydroperoxide in lipid autoxidation
Authors: Morita Makio , Tokita Masako
Published: February 2007

The theory of initiation in lipid autoxidation, which deals with the supply of radicals to the chain reaction, has not been substantively advanced for several decades. Most researchers have long assumed a mechanism of initiation in which main‐product hydroperoxide is centrally responsible for autocatalytic radical generation. However, this paper, in which we investigate autoxidizing methyl linoleate, presents decisive evidence against such an assumption: Autoxidation‐accelerating activity under mild conditions was not found in the chromatographically separated main‐product hydroperoxide fraction but was found in other fractions; and highly active substances with structures containing a peroxide‐linked dimer with two hydroperoxy groups were actually obtained.
Novel imine from Hemsleya macrocarpa var. clavata
Authors: Lin Yu‐ping , Yan Jian , Qiu Ming‐hua
Published: February 2007

The new substance hemsleyin imine A (1) was isolated along with (2S,3S,4R,2′R)‐2‐(2′‐hydroxytetracosanoylamino)‐octadecan‐1,3,4‐triol (2), (2S,3R,4E,8E)‐1‐O‐β‐d‐glucopyranosyl‐3‐hydroxy‐2‐(2′R‐hydroxypalmitoylamino)‐4,8‐octadecadiene (3) from the rhizomes of Hemsleya macrocarpa var. clavata. Their chemical structures were established mainly by spectral analysis and chemical evidence. Compound 1 possesses the skeleton of an imine moiety, which is novel in natural products.
Regulation of the α‐tocopherol transfer protein in mice: Lack of response to dietary vitamin E or oxidative stress
Authors: Bella Deborah L. , Schock Bettina C. , Lim Yunsook , Leonard Scott W. , Berry Crystal , Cross Carroll E. , Traber Maret G.
Published: February 2007

The α‐tocopherol transfer protein (TTP) plays an important role in the regulation of plasma α‐tocopherol concentrations. We hypothesized that hepatic TTP levels would be modulated by dietary vitamin E supplementation and/or by oxidative stress. Mice were fed either a High E (1150 mg RRR‐α‐tocopheryl acetate/kg diet) or a Low E (11.5 mg/kg diet) diet for 2 wk. High E increased plasma and liver α‐tocopherol concentrations approximately 8‐ and 40‐fold, respectively, compared with Low E‐fed mice, whereas hepatic TTP increased approximately 20%. Hepatic TTP concentrations were unaffected by fasting (24 h) in mice fed either diet. To induce oxidative stress, chow‐fed mice were exposed for 3 d to environmental tobacco smoke (ETS) for 6 h/d (total suspended particulate, 57.4±1.8 mg/m3). ETS exposure, while resulting in pulmonary and systemic oxidative stress, had no effect on hepatic α‐tocopherol concentrations or hepatic TTP. Overall, changes in hepatic TTP concentrations were minimal in response to dietary vitamin E levels or ETS‐related oxidative stress. Thus, hepatic TTP concentrations may be at sufficient levels such that they are unaffected by either modulations of dietary vitamin E or by the conditions of environmentally related oxidative stress used in the present studies.
Effects of orlistat therapy on plasma concentrations of oxygenated and hydrocarbon carotenoids
Authors: Sundl Isabella , Pail Elisabeth , Mellitzer Karin , Toplak Hermann , Winklhofer‐Roob Brigitte M.
Published: February 2007

Orlistat is a lipase inhibitor that is applied for treating obesity. Lipases are required for digestion and absorption of dietary lipids and fat‐soluble vitamins and carotenoids. The aim of this study was to compare the effects of orlistat therapy on plasma concentrations of oxygenated (β‐cryptoxanthin, lutein/zeaxanthin) and hydrocarbon (α‐, β‐carotene, lycopene) carotenoids. Six patients with a body mass index (BMI)≥30 kg/m2 received 360 mg/d orlistat over 4.5 mon. Plasma carotenoid concentrations were determined at baseline (T0) and after 3 (T3) and 4.5 mon (T4.5) along with anthropometric, dietary, and biochemical indices, including plasma lipids, retinol, α‐ and γ‐tocopherols, and FA. Baseline BMI was 32.7±1.97 kg/m2. Five of six patients lost weight; the average weight loss was 3.6±2.4% (P=0.47). There were no significant changes in dietary carotenoid intakes. In contrast, plasma α‐and β‐carotene concentrations decreased significantly from T0 to T4.5 by 45% (P=0.006) and 32% (P=0.013), respectively. Plasma lycopene decreased from T0 to T3 but increased again from T3 to T4.5, while β‐cryptoxanthin and lutein/zeaxanthin concentrations did not change. There were no significant alterations in tocopherol, retinol, and FA concentrations. In conclusion, even though weight loss was not significant, orlistat therapy was associated with significant decreases in plasma concentrations of the highly lipophilic hydrocarbon carotenoids, α‐ and β‐carotene.
Positive association between plasma antioxidant capacity and n−3 PUFA in red blood cells from women
Authors: Thorlaksdottir A. Y. , Skuladottir G. V. , Petursdottir A. L. , Tryggvadottir L. , Ogmundsdottir H. M. , Eyfjord J. E. , Jonsson J. J. , Hardardottir I.
Published: February 2007

PUFA are susceptible to oxidation. However, the chain‐reaction of lipid peroxidation can be interrupted by antioxidants. Whether an increased concentration of PUFA in the body leads to decreased antioxidant capacity and/or increased consumption of antioxidants is not known. To elucidate the relationship between plasma total antioxidant capacity (TAC), the concentration of antioxidant vitamins, and the proportion of PUFA in red blood cells (RBC), plasma TAC was measured by a Trolox equivalent antioxidant capacity assay in blood samples from 99 Icelandic women. Concentrations of tocopherols and carotenoids in the plasma were determined by HPLC, and the FA composition of RBC total lipids was analyzed by GC. Plasma TAC and the plasma concentration of α‐tocopherol correlated positively with the proportion of total n−3 PUFA, 20∶5n−3, and 22∶6n−3 in RBC, whereas the plasma lycopene concentration correlated negatively with the proportion of total n−3 PUFA and 20∶5n−3. On the other hand, plasma TAC correlated negatively with the proportion of n−6 PUFA in RBC. Plasma TAC also correlated positively with the plasma concentration of α‐tocopherol, alcohol consumption, and age. Both the plasma concentration of α‐tocopherol and age correlated positively with the proportion of n−3 PUFA in RBC; however, n−3 PUFA contributed independently to the correlation with plasma TAC. Because the proportion of n−3 PUFA in RBC reflects the consumption of n−3 PUFA, these results suggest that dietary n−3 PUFA do not have adverse effects on plasma TAC or the plasma concentration of most antioxidant vitamins.
Cholesterol‐lowering ability of a phytostanol softgel supplement in adults with mild to moderate hypercholesterolemia
Authors: Woodgate Derek , Chan Christina H. M. , Conquer Julie A.
Published: February 2007

Plant sterols, incorporated into spreads and other food sources, have been shown to lower serum cholesterol concentrations. The effect of phytostanol supplementation in softgel form has not been assessed. Our objective was to examine the effects of sitostanol as sitostanol ester in softgel form on serum lipid concentrations in hypercholesterolemic individuals. Thirty hypercholesterolemic adults were supplemented with 1.6 g of free phytostanol equivalents as phytostanol ester (2.7 g stanol esters) or placebo per day for 28 d in a randomized, double‐blind, parallel study design. Phytostanol supplementation resulted in a significant decrease in total cholesterol (TC) (−8%) and LDL‐cholesterol (−9%). There were no alterations in concentrations of HDL‐cholesterol or TG. Nor were the ratios of LDL/HDL or TC/HDL altered significantly. Thus, use of phytostanol ester softgel supplements improved serum total and LDL‐cholesterol concentrations in hypercholesterolemic individuals.
Dose‐dependent hypocholesterolemic actions of dietary apple polyphenol in rats fed cholesterol
Authors: Osada Kyoichi , Suzuki Takashi , Kawakami Yuki , Senda Mineo , Kasai Atsushi , Sami Manabu , Ohta Yutaka , Kanda Tomomasa , Ikeda Mitsuo
Published: February 2007

The dose‐dependent hypocholesterolemic and antiatherogenic effects of dietary apple polyphenol (AP) from unripe apple, which contains approximately 85% catechin oligomers (procyanidins), were examined in male Sprague‐Dawley rats (4 wk of age) given a purified diet containing 0.5% cholesterol. Dietary AP at 0.5 and 1.0% levels significantly decreased the liver cholesterol level compared with that in the control (AP‐free dietfed) group. Dietary AP also significantly lowered the serum cholesterol level compared with that in the control group. However, the HDL cholesterol level was significantly higher in the 1.0% AP fed group than in the control group. Accordingly, the ratio of HDL‐cholesterol/total cholesterol was significantly higher in the 0.5% AP‐fed group and 1.0% AP‐fed group than in the control group. Moreover, the atherogenic indices in the 0.5 and 1.0% AP‐fed groups were significantly lower than those in the control group. The activity of hepatic cholesterol 7α‐hydroxylase tended to be increased by dietary AP in a dose‐dependent manner. In accord with this observation, dietary AP increased the excretion of acidic steroids in feces. Dietary AP also significantly promoted the fecal excretion of neutral steroids in a dose‐dependent manner. These observations suggest that dietary AP at 0.5 or 1.0% level exerts hypocholesterolemic and antiatherogenic effects through the promotion of cholesterol catabolism and inhibition of intestinal absorption of cholesterol.
Effects of margarine and butter consumption on distribution of trans‐18∶1 fatty acid isomers and conjugated linoleic acid in major serum lipid classes in lactating women
Authors: Shahin Alam M. , McGuire Michelle K. , Anderson Nicole , Williams Janet , McGuire Mark A.
Published: February 2007

Trans FA (TFA) have at least one trans double bond and comprise several isomers and types, including many of the CLA (e.g., c9, t11–18∶2 CLA). Some TFA may have adverse effects (e.g., cardiovascular disease), whereas some are though to have beneficial effects (e.g., anticarcinogenicity). The presence of TFA in human tissues and fluids is related to dietary intake, although this relationship is not completely understood—especially in regard to serum lipid fractions. This study was conducted as part of an investigation designed to test the influence of butter (B), “low TFA” margarine (LT), and regular margarine (RM) on milk fat content. Here we tested the secondary hypothesis that consumption of B, LT, and RM by lactating women would result in differential distribution of TFA and CLA in major serum lipid classes. Breastfeeding women (n=11) participated in this randomized Latinsquare study consisting of five periods: intervention I (5 d), washout I (7 d), intervention II (5 d), washout II (7 d), and intervention III (5 d). Extracted serum lipid was separated into cholesterol ester (CE), TAG, and phospholipid (PL) fractions and analyzed for total and isomeric TFA and CLA concentrations. Data indicate that TAG consistently contained the highest concentration of total t‐18∶1. No interaction between treatment and fraction was found for any of the t‐18∶1 isomers identified. Absolute concentration of each t‐18∶1 isomer was greatest during the RM period, regardless of fraction. On a relative basis, concentrations of t10–18∶1 and t12–18∶1 were most responsive to treatment in the CE fraction. The concentration of c9, t11–18∶2 CLA was highest in the TAG fraction and lowest in the PL fraction, regardless of treatment. In summary, these results indicate (i) that there is a differential distribution of some isomeric TFA and CLA among human serum lipid fractions and (ii) that dietary TFA intake influences absolute and relative concentrations of some of the isomers in selected fractions.
Effect of substitution of low linolenic acid soybean oil for hydrogenated soybean oil on fatty acid intake
Authors: DiRienzo Maureen A. , Astwood James D. , Petersen Barbara J. , Smith Kim M.
Published: February 2007

Low linolenic acid soybean oil (LLSO) has been developed as a substitute for hydrogenated soybean oil to reduce intake of trans FA while improving stability and functionality in processed foods. We assessed the dietary impact of substitution of LLSO for hydrogenated soybean oil (HSBO) used in several food categories. All substitutions were done using an assumption of 100% market penetration. The impact of this substitution on the intake of five FA and trans FA was assessed. Substitution of LLSO for current versions of HSBO resulted in a 45% decrease in intake of trans FA. Impacts on other FA intakes were within the realm of typical dietary intakes. No decrease in intake of α‐linolenic acid was associated with the use of LLSO in place of HSBO because LLSO substitutes for HSBO that are already low in α‐linolenic acid.
A high‐saturated fat diet enriched with phytosterol and pectin affects the fatty acid profile in guinea pigs
Authors: Brufau Gemma , Canela Miguel Angel , Rafecas Magda
Published: February 2007

This paper presents the results of a study whose aim was to test the effects of several doses of pectin and phytosterols on the body weight gain and the FA content in emale guinea pigs. The treatments resulted from supplementing with pectin and plant sterol a guinea pig diet (rich in saturated FA), following a 3×3 factorial design, with three levels of pectin (0,3.67 and 6.93%) and three levels of phytosterols (0, 1.37, and 2.45%). Seventy‐two female Dunkin Hartley guinea pigs were randomly assigned to the treatment groups (8 animals/group), the duration of the treatment being 4 wk. Pectin dietary intake led to a significant increase in body weight (P<0.001), food consumption (P=0.025), and feed efficiency (P<0.001), but no influence of phytosterols on weight gain or food consumption was detected. We found a significant negative effect of the addition of phytosterols on lauric, myristic, and palmitic acid concents in feces, and a positive effect on their concentration in plasma and liver, but no significant effect on stearic acid content. Apparent FA absorption was assessed by calculating the ratio of FA in feces and diets that the absorption of the different FA could be compared, and the negative effect of phytosterol supplementation on these ratios, especially for lauric and myristic acids, was established.
Thia fatty acids with the sulfur atom in even or odd positions have opposite effects on fatty acid catabolism
Authors: Dyroy Endre , Wergedahl Hege , Skorve Jon , Gudbrandsen Oddrun A. , Songstad Jon , Berge Rolf K.
Published: February 2007

As tools for mechanistic studies on lipid metabolism, with the long‐term goal of developing a drug for the treatment of lipid disorders, thia FA with the sulfur atom inserted at positions 3–9 from the carboxyl group were fed to male Wistar rats for 1 wk to determine their impact on key parameters in lipid metabolism and hepatic levels of thia FA metabolites. Thia FA with the sulfur atom in even positions decreased hepatic and cardiac mitochondrial β‐oxidation and profoundly increased hepatic and cardiac TAG levels. The plasma TAG level was unchanged and the hepatic acyl‐CoA oxidase activity increased. In contrast, thia FA with the sulfur atom in odd positions, especially 3‐thia FA, tended to increase hepatic and cardiac FA oxidation and acyl‐CoA oxidase and carnitine palmitoyltransferase‐II activities, and decreased the plasma TAG levels. The effects seem to be related to differences in the catabolic rate of the thia FA. Differences between the two groups of acids were also observed with respect to the regulation of genes involved in FA transport and catabolism. Feeding experiments with 3‐ and 4‐thia FA in combination indicated that the 4‐thia FA partly attenuated the effects of the 3‐thia FA on mitochondrial FA oxidation and the hepatic TAG level. In summary, the position of the sulfur atom in the alkyl chain, especially whether it is placed in the even or odd position, is crucial for the biological effect of the thia FA.
Conjugated linoleic acid reduces hepatic steatosis, improves liver function, and favorably modifies lipid metabolism in obese insulin‐resistant rats
Authors: Noto Amy , Zahradka Peter , Yurkova Natalia , Xie Xueping , Nitschmann Evan , Ogborn Malcolm , Taylor Carla G.
Published: February 2007

CLA has been shown to induce or suppress excess liver lipid accumulation in various animal models. Interestingly, the state of insulin resistance may be an important modulator of this effect. The objective of the current study was to determine how feeding a dietary CLA mixture would affect liver lipid accumulation in insulin‐resistant/obese and lean rats in relation to liver function, lipidemia, liver TAG and phospholipid FA composition, and expression of hepatic markers of FA transport, oxidation, and synthesis. Six‐week‐old fa/fa and lean Zucker rats (n=20/genotype) were fed either a 1.5% CLA mixture or a control diet for 8 wk. CLA supplementation reduced liver lipid concentration of fa/fa rats by 62% in concurrence with improved liver function (lower serum alanine aminotransferase and alkaline phosphatase) and favorable modification of the serum lipoprotein profile (reduced VLDL and LDL and elevated HDL) compared with control‐fed fa/fa rats. The fa/fa genotype had two‐thirds the amount of CLA (as % total FA) incorporated into liver TAG and phospholipids compared with the lean genotype. In both genotypes, CLA altered the hepatic FA profile (TAG greater than phospholipids) and these changes were explained by a desaturase enzyme index. Liver‐FA‐binding protein and acyl CoA oxidase, markers of FA transport and oxidation, respectively, were expressed at higher levels in CLA‐fed fa/fa rats. In summary, these results illustrate a strong relationship between the state of insulin resistance and liver lipid metabolism and suggest that CLA acts to favorably modify lipid metabolism in fa/fa Zucker rats.
Selective incorporation of docosahexaenoic acid into lysobisphosphatidic acid in cultured THP‐1 macrophages
Authors: Besson Nelly , Hullin‐Matsuda Francoise , Makino Asami , Murate Motohide , Lagarde Michel , Pageaux Jean‐Francois , Kobayashi Toshihide , Delton‐Vandenbroucke Isabelle
Published: February 2007

Lysobisphosphatidic acid (LBPA) is highly accumulated in specific domains of the late endosome and is involve in the biogenesis and function of this organelle. Little is known about the biosynthesis and metabolism of this lipid. We examined its FA composition and the incorporation of exogenous FA into LBPA in the human monocytic leukemia cell line THP‐1. The LBPA FA composition in THP‐1 cells exhibits an elevated amount of oleic acid (18∶1n−9) and enerichment of PUFA, especially DHA (22∶6n−3). DHA supplemented to the medium was efficiently incorporated into LBPA. In contrast, arachidonic acid (20∶4n−6) was hardly esterified to LBPA under the same experimental conditions. The turnover of DHA in LBPA was similar to that in other phospholipids. Specific incorporation of DHA into LBPA was also observed in baby hamster kidney fibroblasts, although LBPA in these cells contains very low endogenous levels of DHA in normal growth conditions. Our results, together with published observations, suggest that the specific incorporation of DHA into LBPA is a common phenomenon in mammalian cells. The physiological significance of DHA‐enriched LBPA is discussed.
Characterization of hair lipid images by argon sputter etching‐scanning electron microscopy
Authors: Masukawa Yoshinori , Tanamachi Hiroto , Tsujimura Hisashi , Mamada Akira , Imokawa Genji
Published: February 2007

Hair lipid images, as visualized by argon sputter etching‐scanning electron microscopy (ASE‐SEM), reveal convex structures with a stitch pattern (SP) at the cell membrane complex (CMC) in the transverse hair plane. Based on interindividual variation, different features of the convex SP were classified into Types 0 to 4 with the corresponding scores 0 to 4. Observations using hair fibers collected from 27 Japanese females revealed significant positive correlations between the scores and the levels of exogenous lipids, which suggests that exogenous lipids internalized at the CMC predominantly constitute the convex SP. Intraindividual variation with different levels of exogenous lipids among hair fibers derived from individual females may be relevant to the uneven physicochemical properties of hair fibers on the scalp. Observations of 380 hair fibers collected from Japanese (Mongoloid), German and American (Caucasoid) females aged 3 to 77 yr demonstrated similar age‐related changes in the lipid images, which represent an increase and then a decrease in levels of exogenous lipids with increasing age. This suggests that age‐related changes in exogenous lipids are attributable to alterations in sebum excreted during aging and that this elicits age‐related changes in physical parameters, which affect human hair texture.
Lower weight gain and higher expression and blood levels of adiponectin in rats fed medium‐chain TAG compared with long‐chain TAG
Authors: Takeuchi Hiroyuki , Noguchi Osamu , Sekine Seiji , Kobayashi Aiko , Aoyama Toshiaki
Published: February 2007

Previous studies demonstrated that, compared with long‐chain TAG (LCT), dietary medium‐chain TAG (MCT) could improve glucose tolerance in rats and humans. It has been well established that adiponectin acts to increase insulin sensitivity. The effects of dietary MCT on adiponectin serum concentration and mRNA levels in adipose tissue were studied in rats. Male Spague‐Dawley rats were feda diet containing 20% MCT or LCT for 8 wk. After 6 wk of dietary treatment, an oral glucose tolerance test was performed. Rats fed the MCT diet had less body fat accumulation than those fed the LCT diet (P<0.01). The cell diameter of the perirenal adipose tissue, one of the abdominal adipose tissues, was smaller (P<0.01) in the MCT diet group. The serum adiponectin concentration was higher (P<0.01) in the MCT diet group than in the LCT diet group. The adiponectin content in the perirenal adipose tissue was higher (P<0.01) in the MCT diet group. The MCT‐fed group had a higher adiponectin mRNA level in their perirenal adipose tissue (P<0.05). The increase of the plasma glucose concentration after glucose administration istration (area under the curve) was smaller (P<0.01) in the MCT diet group than in the LCT diet group. These findings suggest that dietary MCT, compared with LCT, results in a higher serum adiponectin level with trascriptional activation of the adiponectin gene in rats. We speculate that improved lucose tolerance in rats fed an MCT diet may be, at least in part, ascribed to this higher serum adiponectin level.