UNIPROT:P56851 - FACTA Search

Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P56851 (epididymal)
11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In their transit from the caput to the cauda segments of the epididymis, rat spermatozoa undergo significant modifications in lipid content and composition. The amount of lipid phosphorus per cell decreases, and most lipid classes show specific changes in their constituent fatty acids. A depletion of phosphatidylcholine and phosphatidylethanolamine, concomitant with a virtually unchanged amount of the corresponding plasmalogens, are the major alterations, plasmenylcholine thereby becoming the major phospholipid. Diphosphatidylglycerol, sphingomyelin and the phosphoinositides decrease to a lesser extent or do not change at all, also resulting in relative increases with sperm maturation. Concerning the fatty acids, the proportions of oleate (C18:1, n-9) and linoleate (C18:2, n-6) in most lipids decrease on movement of sperm from caput to cauda, augmenting in turn the proportions of longer-chain (C20 to C24) and more unsaturated fatty acids. Docosapentaenoate (C22:5, n-6) is a major acyl chain present in all lipids at both stages, but uncommon long-chain polyenoic fatty acids of the n-9 series are also present, being almost exclusively found in the choline glycerophospholipids. These fatty acids are found to undergo the most significant changes during sperm maturation. They are minor components of plasmenylcholine in immature spermatozoa, but increase severalfold on maturation, representing more than half of the acyl chains of this major lipid in cells from the cauda. The high concentration of n-9 polyenes in mature sperm plasmenylcholine raises intriguing questions on the possible role epididymal cells may play in providing spermatozoa with such an unusual phospholipid. These plasmenylcholines could contribute to the characteristic lipid domain organization of the mature spermatozoa plasma membrane.
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PMID:Lipid remodelling during epididymal maturation of rat spermatozoa. Enrichment in plasmenylcholines containing long-chain polyenoic fatty acids of the n-9 series. 156 71

An enriched plasma membrane fraction was isolated from caput, corpus, and cauda rat spermatozoa and analyzed for lipid and protein content, thermal phase transition temperature using electron paramagnetic resonance spectroscopy (EPR), and enzymatic assays of calcium-dependent ATPase activity. Based on sperm concentration, total membrane phospholipid, cholesterol, and protein content declined as sperm passed through the epididymis. A more refined analysis of the bulk plasma membrane phospholipid revealed that approximately 56% of the phospholipid consisted of choline (PC) and ethanolamine (PE) phosphoglycerides; the remainder consisted of sphingomyelin (SM), phosphatidylserine (PS), and diphosphatidylglycerol (DPG). The mole percent of PE increased in sperm proceeding from the caput to the corpus epididymis and then declined from the corpus to the cauda epididymis. The phospholipid-bound fatty acids consisted primarily of palmitate (C16:0) and stearate (C18:0), with a significant increase in the mole percent of the docosapentenoyl acyl group (C22:5) in cauda sperm. Arrhenius' plots of the EPR peak height signals using the lipid soluble spin label, 5-doxyldecane, and the calcium-dependent ATPase activity as a function of temperature demonstrated a change in the apparent fluidity of the membrane and energy of activation of the calcium-dependent ATPase associated with the three sperm membrane preparations. These data suggest that the apparent fluidity and biochemical composition of the sperm membrane change during epididymal maturation.
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PMID:Correlation between changes in rat sperm membrane lipids, protein, and the membrane physical state during epididymal maturation. 184 30

In Japan, Hochu-ekki-to (TJ-41), a Japanese Kampo preparation is used extensively in the treatment of idiopathic male infertility. In order to elucidate the mechanism of how this drug affects spermatogenesis, we examined the effects of the sera from male mice to which TJ-41 was administered orally, on protein synthesis in cultured hamster epididymal cells. Golden hamster epididymal cells were cultured in RPMI1640 medium supplemented with FCS for 7 to 10 days. After the initial culture period, the medium was changed to RPMI1640 supplemented with 1 microCi/ml [3H]-leucine and 10% serum from male ICR mice to which TJ-41 was orally administered for 7 days. The culture was then continued for 20 hours, and the uptake of [3H]-leucine into the cultured hamster epididymal cells was measured. The uptake of [3H]-leucine was significantly higher (p < 0.05) in cells cultured in media supplemented with sera from the TJ-41 treated mice than in cells cultured with control sera. Elements in the sera from control and TJ-41 treated mice were analyzed by high performance liquid chromatography (Waters HPLC, type 510; Milipore) with a mu-Bondapack C18 column. Several new peaks were detected in the sera from TJ-41 treated mice. These results and the clinical data suggest that TJ-41 may promote the synthesis of several proteins which might he related to the functional maturation of spermatozoa in the epididymis.
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PMID:Effects of hochu-ekki-to, a Japanese kampo medicine, on cultured hamster epididymal cells. 787 42

The present study investigates fat deposition, variances of fatty acid (FA) composition, and lipogenic enzyme activities through dietary medium- and long-chain triglyceride (MCT and LCT) supplementation in growing rats. Eighteen male Wistar rats were divided into three groups and fed isocalorically for 4 weeks with control (based on AIN 76), MCT (C8:0 26%), or LCT (corn oil 25%) diets. Compared to the control group with 0.28 +/- 0.01, feed efficiency was lower in the MCT rats and greater in the LCT rats (0.24 +/- 0.01 and 0.33 +/- 0.01, respectively). Weights of perirenal and epididymal adipose tissue pads of the MCT rats were similar to those of the control group, but were significantly lower than those of the LCT group. Whole-body carcass components data of MCT rats showed the decrease in moisture and protein contents compared to those of control and LCT rats. Fat content of LCT rats was 25-30% higher than those of the MCT and control group. Glucose-6-phosphate dehydrogenase, citrate cleavage enzyme, and malic enzyme activities of liver and epididymal adipose tissue were markedly low in LCT rats. In the MCT group, however, lipogenic enzyme activities were not suppressed, and malic enzyme activity was drastically increased. FA composition of whole-body triglycerides and epididymal adipose tissue in MCT rats showed that C16:0 and C16:1 levels were higher than those of the LCT rats. In contrast, FA composition of the LCT group presented high C18:2 content.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Influence of dietary medium- and long-chain triglycerides on fat deposition and lipogenic enzyme activities in rats. 829 19

The free fatty acid (FFA) concentration in the epididymal cytosol of the adult rat was found to be 20-fold higher than in the serum. The binding of [3H] dihydrotestosterone to epididymal rat androgen binding protein (rABP) was modified by physiological concentrations of saturated and unsaturated fatty acids. Polyunsaturated fatty acids inhibited the binding more efficiently than monounsaturated or saturated fatty acids. Scatchard analysis and Dixon plots indicated that the number of binding sites decreased in presence of unsaturated fatty acids with an inhibition constant (Ki) of 4 microM for arachidonic acid (C20:4) and 20 microM for oleic acid (C18:1). These results indicate that unsaturated fatty acids induce alterations in rABP steroid-binding properties that could modulate the endocrine function of rABP.
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PMID:Free fatty acid-induced alterations in the steroid-binding properties of rat androgen-binding protein. 842 2

Effects of the conjugated linoleic acid (CLA) isomers cis-9, trans-11 (c9,t11 CLA) and trans-10, cis-12 (t10,c12 CLA) on lipid metabolism and markers of peroxisome proliferation were investigated in hamsters fed on purified diets containing 30% energy as fat and 0.1 g cholesterol/kg for 8 weeks. Four groups (n 32 each) received diets without CLA (control), with a mixture of equal amounts of c9,t11 and t10,c12 CLA (CLA mix), with c9,t11 CLA, and with t10,c12 CLA. The total amount of CLA isomers was 1.5% energy of 6.6g/ kg diet. CLA was incorporated into glycerides and exchanged for linoleic acid in the diet. Compared with the control, the CLA mix and t10,c12 CLA decreased fasting values of LDL- (21 and 18% respectively) and HDL-cholesterol (8 and 11%), increased VLDL-triacylglycerol (80 and 61%, and decreased epididymal fat pad weights (9 and 16%), whereas c9,t11 CLA had no significant effects. All CLA preparations increased liver weight, but not liver lipids. However, the increase in liver weight was much less in the c9,t11 CLA group (8%) than in the other two groups (25%) and might have been caused by the small amount of t10,c12 CLA present in the c9,t11 CLA preparation. Liver histology revealed that increased weight was due to hypertrophy. Markers of peroxisome proliferation, such as cyanide-insensitive palmitoyl CoA oxidase (EC 1.3.3.6) and carnitine acetyl transferase (EC 2.3.1.7) activities, were not increased by CLA. Both c9,t11 CLA and t10,c12 CLA were incorporated into phospholipids and triacylglycerols, but t10,c12 CLA only about half as much as c9,t11 CLA. In addition, linoleic acid and linolenic acid concentrations were lower in lipids of the t10,c12 CLA group compared with the c9,t11 CLA group. These data suggest that t10,c12 CLA stimulated the oxidation of all C18 polyunsaturated fatty acids. The results indicate that the t10,c12 CLA isomer, and not the so-called natural CLA isomer (c9,t11), is the active isomer affecting lipid levels in hamsters.
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PMID:Effects of conjugated linoleic acid (CLA) isomers on lipid levels and peroxisome proliferation in the hamster. 1065 80

The most widely known health benefits of tea relate to the polyphenols as the principal active ingredients in protection against oxidative damage and in antibacterial, antiviral, anticarcinogenic, and antimutagenic activities, but polyphenols in tea may also increase insulin activity. The objective of this study was to determine the insulin-enhancing properties of tea and its components. Tea, as normally consumed, was shown to increase insulin activity >15-fold in vitro in an epididymal fat cell assay. Black, green, and oolong teas but not herbal teas, which are not teas in the traditional sense because they do not contain leaves of Camellia senensis, were all shown to increase insulin activity. High-performance liquid chromatography fractionation of tea extracts utilizing a Waters SymmetryPrep C18 column showed that the majority of the insulin-potentiating activity for green and oolong teas was due to epigallocatechin gallate. For black tea, the activity was present in several regions of the chromatogram corresponding to, in addition to epigallocatechin gallate, tannins, theaflavins, and other undefined compounds. Several known compounds found in tea were shown to enhance insulin with the greatest activity due to epigallocatechin gallate followed by epicatechin gallate, tannins, and theaflavins. Caffeine, catechin, and epicatechin displayed insignificant insulin-enhancing activities. Addition of lemon to the tea did not affect the insulin-potentiating activity. Addition of 5 g of 2% milk per cup decreased the insulin-potentiating activity one-third, and addition of 50 g of milk per cup decreased the insulin-potentiating activity approximately 90%. Nondairy creamers and soy milk also decreased the insulin-enhancing activity. These data demonstrate that tea contains in vitro insulin-enhancing activity and the predominant active ingredient is epigallocatechin gallate.
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PMID:Tea enhances insulin activity. 1242 80

To investigate the incorporation of acetate into fatty acids and their turnover, the time courses for the incorporation of labeled acetate into lipids in the liver and epididymal adipose tissue (adipose tissue) after the oral administration to rats were examined for 10 d. The labeled acetate was abundantly incorporated into lipids, mainly into triacylglycerols (TAG) in the liver, reached a maximum at 2 h after the administration and then quickly decreased. In the adipose tissue, the incorporation of the acetate reached a maximum after 8 h and began to decrease slowly after 2 d. The acetate incorporation into the lipids was markedly lower in the liver, plasma and adipose tissue of rats fed the corn oil diet than in those fed the fat-free diet. However, the half-lives of esterified fatty acids were similar in both dietary groups. The half-lives of esterified C16:0 and C18:1 in the decreasing phase were 5.4 and 8.9 h, respectively, in the liver, and 4.3 and 5.6 d, in the adipose tissue. The time courses for incorporation into plasma lipids were parallel to those in the liver. Thus the fatty acids synthesized in the liver appeared to be transported to adipose tissues and to stay there longer. Moreover, it is remarkable that 30% of the acetate radioactivities administered were found after 2 h in the whole liver: 75% of the products from the acetate at the maximum were lipids and 61%, of the lipids, TAG. The major products from acetate in the liver were lipids.
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PMID:Labeled acetate incorporation into lipids and lipid elimination after oral administration in rat liver and adipose tissue. 1602 97

Attention was recently drawn to differences in the fatty acid pattern of liver phospholipids and triglycerides in animal models of type 1 and type 2 diabetes. The present study extends this knowledge to epididymal or parametrial adipose tissue lipids. The fatty acid pattern of such lipids was established in four fed female normal rats, four overnight fasted female normal rats, six fed female rats rendered diabetic by an injection of streptozotocin 3 days before sacrifice (STZ rats), and four female and four male Goto-Kakizaki rats (GK rats) also examined in the fed or fasted state. In addition to the fasting-induced and diabetes-related changes in plasma D-glucose and insulin concentrations, differences in either the weight percentage of fatty acids or the paired ratio between distinct fatty acids were often encountered. For instance, in the GK rats, gender differences were observed in the weight percentage of C18:2omega6, as well as C18:2omega6/C18:3omega6, C18:3omega6/C20:4omega6, C20:5omega3/C22:5omega3 and C22:5omega3/C22:6omega3 ratios. When compared to normal rats, the activity of Delta9-desaturase was markedly increased in GK rats and, to a lesser extent, in STZ rats. Starvation also increased to some extent the activity of Delta9-desaturase. The relative content of C22:6omega3 was also higher in diabetic than in normal rats. Further differences between GK and STZ rats concerned the generation of C18:3omega6 from C18:2omega6, C20:4omega6 from C18:3omega6, and C20:5omega3 from C18:3omega3. Several differences found in the adipose tissue of GK versus STZ rats were reminiscent of those recently identified in the liver triglycerides of these two types of diabetic animals, suggesting a common regulatory mechanism, possibly linked to the higher insulinemia of GK rats versus STZ rats.
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PMID:Fatty acid content and pattern of epididymal and parametrial adipose tissue lipids in streptozotocin (type 1) and Goto-Kakizaki (type 2) diabetic rats. 1708 31

The purpose of this study was to investigate the effects of conjugated linoleic acid (CLA) on the fatty acid composition of plasma, liver, and epididymal fat pads in rats. Seventy-two male Sprague-Dawley rats were divided into four groups and received beef tallow (BT), fish oil (FO), beef tallow with CLA (BTC), and fish oil with CLA (FOC). All the rats were fed an experimental diet containing 12% (wt/wt) total fat, including CLA at 1%, for 30 weeks. The fatty acid analyses of the plasma, liver, and epididymal fat pads were performed by the one-step methylation method, followed by gas chromatography. Monounsaturated fatty acid (MUFA) levels in the plasma were significantly reduced in the BTC group as compared to the BT group. The levels of C18:1 and C20:4 in the liver were significantly lower in the BTC group than in the BT group (P < .05). CLA was detected in the epididymal fat pads of the rats that did not receive supplemental CLA (the BT and FO groups), indicating de novo synthesis. CLA caused significant decreases in C18:1 fatty acid levels in both the BTC and FOC groups in epididymal fat pads. C22:6 was significantly higher in the liver microsomes of the BTC group, as compared to the BT group. MUFA was stored at higher levels in the epididymal fat pads and was significantly lower in level in the CLA-supplemented (BTC and FOC) groups as compared to the BT and FO groups (P < .05). In conclusion, dietary CLA supplementation in rats altered fatty acid composition in a tissue-specific manner. CLA was stored mainly in the epididymal fat pad. The results also suggested that CLA may inhibit the conversions of C18:0 to C18:1 and C18:2 to C20:4 fatty acid, resulting in significantly lower levels of C18:1 and C20:4 in the livers of the BTC group as compared to the BT group.
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PMID:Effects of conjugated linoleic acid supplementation on fatty acid composition in the plasma, liver, and epididymal fat pads of male-Sprague Dawley rats. 1880 Aug 89

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