Astaxanthin improves the developmental competence of in vitro-grown oocytes and modifies the steroidogenesis of granulosa cells derived from bovine early antral follicles.

In this study we investigated the effect of astaxanthin (Ax), which exhibits strong antioxidant activity, during invitro growth (IVG) on the developmental competence of oocytes and steroidogenesis of granulosa cells derived from early antral follicles. Bovine oocyte-cumulus-granulosa complexes collected from early antral follicles were cultured for 12 days in the presence or absence (control) of 500µM Ax. The viability of oocytes and antrum formation in the granulosa cell layer during IVG culture were greater in the presence than absence of Ax (P<0.05). Regardless of Ax treatment, 17ß-oestradiol production increased during IVG culture; however, progesterone production was significantly lower in the presence than absence of Ax (P<0.05). Reactive oxygen species levels were lower in Ax-treated oocytes than in controls after IVG (P<0.05). Although nuclear maturation and cleavage rates did not differ between the Ax-treated and control groups, Ax treatment led to weaker cathepsin B activity in oocytes and better blastocyst rates than in controls (P<0.05). Accordingly, Ax treatment during IVG increased the total number of cells in blastocysts (P<0.05). These results indicate that Ax supplementation of IVG medium improves the quality of bovine oocytes due to its antioxidative effects on growing oocytes and its suppression of the luteinisation of granulosa cells.

Isotype-specific selection of high affinity memory B cells in nasal-associated lymphoid tissue.

Mucosal immunoglobulin (Ig)A dominance has been proposed to be associated with preferential class switch recombination (CSR) to the IgA heavy chain constant region, Calpha. Here, we report that B cell activation in nasal-associated lymphoid tissue (NALT) upon stimulation with the hapten (4-hydroxy-3-nitrophenyl)acetyl (NP) coupled to chicken gamma globulin caused an anti-NP memory response dominated by high affinity IgA antibodies. In the response, however, NP-specific IgG(+) B cells expanded and sustained their number as a major population in germinal centers (GCs), supporting the view that CSR to IgG heavy chain constant region, Cgamma, operated efficiently in NALT. Both IgG(+) and IgA(+) GC B cells accumulated somatic mutations, indicative of affinity maturation to a similar extent, suggesting that both types of cell were equally selected by antigen. Despite the selection in GCs, high affinity NP-specific B cells were barely detected in the IgG memory compartment, whereas such cells dominated the IgA memory compartment. Taken together with the analysis of the V(H) gene clonotype in GC and memory B cells, we propose that NALT is equipped with a unique machinery providing IgA-specific enrichment of high affinity cells into the memory compartment, facilitating immunity with high affinity and noninflammatory secretory antibodies.

Preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil for oral squamous cell carcinoma.

The objectives of this study were to evaluate survival in 141 patients with stage II-IV oral squamous cell carcinoma (OSCC) treated with preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil (IADCPIVF) via the superficial temporal artery, and to clarify the prognostic factors. The study population included 59 patients with stage II OSCC, 34 with stage III, and 48 with stage IV. After IADCPIVF, 139 patients underwent surgery; minimally invasive surgeries (MIS) including excisional biopsy were performed on 96 patients with a remarkably good response to IADCPIVF. The primary tumour response rate was 99.3% (complete response rate 56.7%, good partial response rate 17.0%, fair partial response rate 25.5%). Additionally, there were no serious adverse events associated with IADCPIVF. The 5-year overall survival rate was 74.6% (stage II 83.6%, stage III 72.7%, stage IV 64.8%). In the multivariate analysis of survival, T classification and clinical tumour response were significant prognostic factors. Eight (8.3%) of the patients who received MIS had primary recurrence and six were salvaged. In conclusion, IADCPIVF is safe and efficacious for treating OSCC, and MIS could reduce the extent of primary tumour resection in the case of a remarkably good response.

Isolation and characterization of plasma membrane from lactating bovine mammary gland.

Plasma membranes were isolated from lactating bovine mammary gland. Two crude membrane fractions; medium/d 1.033 (light membrane) and 1.033/1.053 interfaces (heavy membrane), were obtained by Ficoll density gradient centrifugation of osmotically washed microsomal fraction. Two crude membranes were further purified separately by sucrose density gradient centrifugation. Both light and heavy membranes banded at a sucrose density of 1.14. The purified membranes appeared as heterogeneous smooth membrane vesicles on electron microscopy. The contaminating suborganelles were not detected. The yield of the purified membranes relative to the homogenate was 1.2%. The degree of purity of the membranes was shown by a great increase in the specific activity of 5'-nucleotidase over the homogenate of 20-fold for light membrane and of 16-fold for heavy membrane. The relative activities of Mg2+-ATPase, (Na+ + K+)-ATPase, gamma-glutamyl transpeptidase, phosphodiesterase I, alkaline phosphatase and xanthine oxidase were also high (12-18-times) and nearly 20% of these enzymes was recovered. The activity of marker enzyme for mitochondria, endoplasmic reticulum and Golgi apparatus was very low, while that of acid phosphatase for lysosome was relatively high (5-times). DNA and RNA contents were very low. The major polypeptides rich in other suborganelles were not detected profoundly in the membrane fraction and the polypeptide composition in both light and heavy membranes were similar upon SDS-polyacrylamide gel electorphoresis.

Purification and characterization of major glycoproteins, PAS-6 and PAS-7, from bovine milk fat globule membrane.

Two major glycoproteins (PAS-6 and PAS-7) from bovine milk fat globule membrane were selectively extracted with urea and KCl, co-purified by repeated gel filtration on Sephacryl S-200 and then separated by affinity chromatography on concanavalin A-agarose column. The two purified glycoproteins showed a single band by SDS-PAGE, and their molecular masses were estimated to be 50 kDa for PAS-6 and 47 kDa for PAS-7. Both PAS-6 and PAS-7 were resolved several variants by analytical isoelectric focusing. These were shifted to a single band at pI 6.2 for PAS-6 and at pI 6.5 for PAS-7 by neuraminidase. PAS-6 contained 7.1% and PAS-7 5.5% of carbohydrate; the molar ratio of fucose:mannose:galactose:N-acetyl galactosamine:N-acetyl glucosamine:sialic acid was 1.0:3.0:2.0:6.1:5.0:1.3 for PAS-6 and 1.0:3.1:2.2:0:4.1:1.1 for PAS-7. Mild alkaline treatment and affinity to various lectins indicated that PAS-6 had O- and N-linked oligosaccharide chains, while PAS-7 had only the N-linked type. The major amino acid residues of PAS-6 were Glu, Ser and Gly, and those of PAS-7 were Asp, Glu, Gly and Leu. The N-terminal amino acids of both glycoproteins were blocked. PAS-6 and PAS-7 digested with trypsin had a different peptide map, two major peptides having the same retention time on HPLC and being common to PAS-6 and PAS-7 having the same amino acid sequences of H-Gln-Ser-Gly-Asn-Lys-Asn-Pro-Ser-Glu-Ile-Ser-OH and H-Ile-Phe-Pro-Gly-Asn-Met-Asp-Asn-Ser-His-Lys-OH.

Identification of alpha-, beta-, gamma-, and delta-tocopherols and their contents in human milk.

Human milk was found to contain naturally occuring beta-, gamma- and delta-tocopherol and gamma-tocotrienol in addition to alpha-tocopherol on thin-layer chromatography. Some of the tocopherols were also identified by gas-liquid chromatography and mass spectrometry. The mean content of alpha-, beta-, gamma- and delta-tocopherol was 319.3, 7.6, 23.9 and 4.9 mug/g lipid in twelve human colostra 52.5, 1.8, 10.2 and 2.3 mug/g lipid in three transitional milks and 61.7, 2.0, 9.2 and 1.1 mug/g lipid in three normal milks, respectively. A markedly high concentration of alpha-tocopherol was found in colostrum compared with transitional and normal human milk. Gamma-Tocotrienol was detected in colostrum as only one tocotrienol derivative on thin-layer chromatography. The importance of colostrum as the source of vitamin E for the newborn is suggested.

Selective extraction of marker enzymes of bovine milk fat globule membrane by nonionic detergents.

Large amounts (66-97%) of marker enzymes such as alkaline phosphatase, 5'-nucleotidase, phosphodiesterase I, and gamma-glutamyl transpeptidase of bovine milk fat globule membrane (MFGM) were selectively solubilized by nonionic detergents such as Triton X-100, Tween 20, Nonidet P-40, Liponox NCK, and Emulgen 109-P. On the other hand, the extractability of MFGM protein with these detergents was less than 50%. Judging from the recovery of total activity, it is likely that alkaline phosphatase, phosphodiesterase I, and gamma-glutamyl transpeptidase are activated by nonionic detergents, whereas 5'-nucleotidase is somewhat inhibited by the detergents, except for Tween 20, and acid phosphatase is strongly inhibited by all detergents. In addition, solubilization of the protein with the nonionic detergents was found to be somewhat selective by SDS-polyacrylamide gel electrophoresis. There was no appreciable difference between the five brands of nonionic detergents used as regards the extractability of protein and the enzymatic activity of the extracted marker enzymes of MFGM, except that the solubilizing ability of Tween 20 was relatively low.

Transfer of orally administered alpha-tocopherol into human milk.

The transfer of orally administered alpha-tocopherol (1.1 g) into breast milk reached a maximum value of 414 micrograms/100 g milk, which was 6.6-fold the pre-supplemental level, after three days and declined to the base line level after five days. The amount of alpha-tocopherol recovered in the milk was 0.11%. The alpha-tocopherol equivalent/PUFA ratio (mg/g) was increased from 0.25 to values between 0.7 and 1.7 by the administration.

Binding form of vitamin B2 in bovine milk: its concentration, distribution and binding linkage.

The contents of total, free, and bound vitamin B2 (B2) in bovine milk and their distribution in four separate milk fractions, including milk during the early lactation stage, were estimated. The total B2 content in whole mature milk was 179 +/- 25 micrograms/100 g (n = 16), and its distribution in the cream, whey, skim milk membrane, and casein fractions was 6, 67, 9, and 18%, respectively. The amount of flavins bound to protein in the total B2 was 13.6% in whole milk and rich in membrane fraction. The total B2 content (micrograms/100 g of milk) was higher in colostrum at 1-3 days (287 +/- 120) than in colostrum at 4-7 days (173 +/- 27), in transitional milk (182 +/- 33), and in mature milk (179 +/- 44). The bound flavin content decreased slightly as lactation progressed (20-30 micrograms/100 g), but the ratio of bound/total B2 did not vary (12-15%). Milk fat globule membrane (MFGM) contained 414 +/- 65 micrograms of B2/g of protein, most of it being bound to protein (92%). Market milks contained as much total B2 as raw whole milk, but the amount of bound form was only 2%. Guanidine HC1, urea, sodium dodecyl sulfate, pH at 3.0-3.5, delipidation, and boiling released most of the B2 bound to protein, suggesting that bound flavins bind to milk proteins by a hydrophobic linkage.

Purification and separation of multiple forms of lactophorin from bovine milk whey and their immunological and electrophoretic properties.

Lactophorin is designated as a glycoprotein, which is present in bovine milk whey and reacts to the antiserum of the soluble glycoprotein of bovine milk fat globule membrane. The lactophorin was purified by DEAE-cellulose (pH 7.7), Sephadex G-100, and then Bio Gel A-15m from the component-3 fraction of the proteose-peptone fraction of bovine milk whey. The purified lactophorin was separated into seven components by DEAE-cellulose chromatography at pH 8.6. The seven components (LP-1 to -7) of lactophorin were almost homogeneous, but the respective bands were somewhat broad and varied in mobilities on disc electrophoresis. The seven lactophorin components fused completely to the antisoluble glycoprotein of milk fat globule membrane on double immunodiffusion but showed different mobilities of precipitation lines on immunoelectrophoresis. The results indicated that lactophorin consisted of multiple forms but had a common set of antigenic determinant groups against anti-soluble glycoprotein.

Characterization of multiple forms of lactophorin isolated from bovine milk whey.

A glycoprotein that reacted to the antisoluble glycoprotein of bovine milk fat globule membrane was purified from the proteose-peptone of whey and designated lactophorin. Lactophorin was separated into seven components. Lactophorin and the seven components were rich in aspartic acid, threonine, serine, glutamic acid, leucine, and lysine. The content of threonine, glycine, isoleucine, lysine, and arginine varied in each component. The ratio of fucose, mannose, galactose, N-acetylgalactosamine, N-acetylglucosamine, and sialic acid of lactophorin, which contains about 18% saccharide, were 1, 6.6, 10.3, 5.5, 9.7, and 11.6, respectively, while the respective ratio of the seven components were 1, 5 to 6, 7 to 9, 3 to 4, 6 to 8, and 4 to 12. Sialic acid content varied in each component. Protein-carbohydrate linkage was N- and o-glucoside linkage. Lactophorin consisted of seven polypeptides (I to VII) with apparent molecular weights 17,000 to 67,000. Bands I, II, VI, and VII were glycoprotein. Bands VI and VII were major and had antigenicity to anti-soluble glycoprotein, while bands I to V were minor polypeptides. Component 1 consisted of only one polypeptide (VII), whereas the components 2 to 7 contained two major (VI, VII, or both) and several minor polypeptides. The sedimentation pattern of each component was a single and almost symmetrical peak. Sedimentation coefficient was 3.79 to 5.64 S and also varied in lactophorin. The results indicate that lactophorin has multiple forms.

Enzymic modification of alpha s1-casein with peptidylarginine deiminase: preparation of less acid-coagulable and less calcium-sensitive casein.

Enzymic modification with peptidylarginine deiminase (EC 3.5.3.15) enabled five out of six arginyl residues in alpha s1-casein to be converted to citrullyl residues, only the N-terminal arginyl residue remaining unaffected. An increase in the net negative charge was confirmed by PAGE. The isoelectric point was decreased from 4.46 for the intact alpha s1-casein to 4.30 for the deiminated type, while simultaneously lowering the acid-precipitation starting point from pH 5.17 to pH 4.62. The deiminated alpha s1-casein self-associated less in the absence of Ca and was less Ca-sensitive than the native type, although its Ca-binding ability was slightly enhanced. In the presence of 25 mM-CaCl2 and kappa-casein, Ca-induced precipitation of alpha s1-casein did not occur, the solution of the mixture remaining transparent. Deimination of alpha s1-casein resulted in altering its characteristics, possibly by interfering with interactions through hydrophobicity and/or hydrogen bonding. The positive charge of the arginyl residues might play an important role in casein micelle formation.

Rapid and simple procedure for purifying PAS-4 glycoprotein from bovine milk fat globule membrane.

The isolation and partial characterization of PAS-4 glycoprotein (78 kDa) from bovine milk fat globule membrane (MFGM) is described. PAS-4 was selectively extracted with Triton X-114 nonionic detergent and then fractionated on DEAE-Sepharose at pH 7.5. The PAS-4 fraction that was not bound on DEAE-Sepharose gave a single band by SDS-PAGE. The recovery of PAS-4 was 57.4% from MFGM. An amino acid analysis found a high percentage of nonpolar residues. Approximately 7.2% of carbohydrate from PAS-4 was composed of mannose, galactose (Gal), N-acetylglucosamine, N-acetylgalactosamine (GalNAc), and sialic acid, most of the Gal and GalNAc in PAS-4 being released after mild alkaline hydrolysis. This indicated that PAS-4 contained both N- and O-linked sugar chains in concordance with the results of lectin affinity. PAS-4 had apparent isoelectric points of 7.45, 7.41, and 7.32, but these were shifted to pI 7.47 by a neuraminidase treatment. The apparent molecular weight of PAS-4 after deglycosylation with N-glycanase was approximately 57,000 by SDS-PAGE.

Enzymatic Properties of Two Calcium-stimulated ATPases in the Neutral and Acidic pH Regions Found in the Membrane Fraction of Human Milk.

Two calcium-stimulated ATPases at optimal pH values of 5.0 and 7.0, which are designated as acid and neutral Ca(2+) -ATPase, respectively, were found in the membrane fraction of human milk, and their enzymatic properties were studied. For maximal activity, neutral Ca(2+)-ATPase required 0.45 mM Ca ion, while acid Ca(2+) -ATPase required 207 mM Ca ion. Neutral Ca(2+) -ATPase activity was not enhanced by adding the Mg ion at more than 0.1 mM. Among the nucleotides, neutral Ca(2+) -ATPase showed a higher substrate specificity to GTP, CTP, ITP, and UTP than to ATP, while ATP was the best substrate for acid Ca(2+) -ATPase. Neutral and acid Ca(2+) -ATPases had apparent Km values of 0.361 and 0.192 mM, and Vmax of 186 and 178 µmol ATP hydrolyzed/mg of protein per min, respectively. Both Ca(2+) -ATPases were potently inhibited by fluoride, lanthanide, vanadate, and p-chloromercuribenzoate, and inactivated by EDTA, EGTA, and CDTA, but were unaffected by N-ethylmaleimide, NaN3, ouabain, oxidized glutathione, or oligomycin, and were inactivated by heating at 60°C for 10 min. These enzymes were concentrated in the membrane fraction of the cream and skim milk membrane.

Accumulation of immunoreactive opsin on plasma membranes in degenerating rod cells of rd/rd mutant mice.

Immunoreactive opsin was detectable in the apical portion of normally developing photoreceptor cells on postnatal day 3 by the indirect enzyme-labeled antibody method. Immunoreactivity increased and had extended from the central retina to the periphery by the advanced stages of development. In the rd mutant retinas, accumulated opsin was present in the apical portion and in the outer nuclear layer on postnatal day 8. Immunoreactive opsin mainly was present in the outer nuclear layer by day 14, even being detectable on day 28. No immunoreactivity was present in the remaining cones. Electron microscopic immunocytochemistry confirmed the association of immunoreactive opsin with the persistent rod cell plasma membrane. Molecular weight of immunoreactive opsin in 14-day-old rd mutant mouse retina, as estimated by gel filtration chromatography, was large and did not seem to be degraded. These findings indicate that accumulated rhodopsin continues to function in the plasma membrane because an electroretinogram could be made after day 14 for the rd mutant mouse retina.

Structures of the N-linked sugar chains in PAS-7 glycoprotein sharing the same protein core with PAS-6 glycoprotein from the bovine milk fat globule membrane.

Glycoproteins PAS-6 (50 kDa) and -7 (47 kDa) from the bovine milk fat globule membrane share a common protein core but differ in their carbohydrate moiety. We here analyzed and proposed the structures of the N-linked sugar chains of PAS-7. The N-linked sugar chains were liberated from PAS-7 by hydrazinolysis and, after modifying the reducing ends with 2-aminopyridine (PA), were separated into one neutral (7N, 55%) and two acidic (7M, mono-, 43%; 7D, di-, 2%) sugar chain groups. The latter were converted into neutral groups (7MN and 7DN) by sialidase digestion. 7N was finally separated into 5 chains (7N1A, 7N1B-1, 7N1B-2, 7N2A, and 7N2B), and 7MN and 7DN were separated into 3 (7MN1, 7MN2, and 7MN3) and 2 (7DN1 and 7DN2) chains, respectively. The structure of each of these PA-neutral sugar chains was determined by sugar analysis, sequential exoglycosidase digestion, partial acetolysis, and 1H-NMR spectroscopy. The results show that the 10 sugar chains were of the biantennary complex type with and without fucose. The structure of 7N2A, one of the major sugar chains, was proposed as; [structure: see text] A structural comparison between PAS-6 and -7 indicated that, although they shared the same protein core, their sugar moiety was markedly different, involving the existence of a different pathway during the post-transcriptional modification.

Purification and characterization of novel whey glycoprotein WGP-88 which binds to a monoclonal antibody to PAS-4 glycoprotein in the bovine milk fat globule membrane.

A monoclonal antibody to the PAS-4 glycoprotein (78 kDa) of the bovine milk fat globule membrane (MFGM) specifically recognized PAS-4, and was named KAS4. A component recognized by KAS4 was found in whey protein, this being a glycoprotein of 88 kDa by SDS-PAGE and named WGP-88. WGP-88 was purified and characterized in comparison with PAS-4. WGP-88 had apparent pI values of 6.45 and 6.39, while those of PAS-4 were 7.39 and 7.35. Neuraminidase digestion shifted the pI values of WGP-88 to 6.57 and of PAS-4 to 7.52. WGP-88 was rich in polar amino residues (44.9 mol%), while PAS-4 was abundant in nonpolar amino acid residues (48.7 mol%). WGP-88 contained 17.1% of carbohydrate and PAS-4 had 7.2%. The results of reductive hydrolysis, N-glycanase digestion, and a lectin blot analysis suggested that N- and O-linked sugar chains were contained in both glycoproteins. WGP-88 and PAS-4 had a different N-terminal amino acid sequence. WGP-88 and PAS-4 respectively inhibited competitively the binding of KAS4 to PAS-4 and WGP-88. Our studies revealed WGP-88 recognized by KAS4 mAb to be a novel whey protein and to have different biochemical properties from those of PAS-4.

Local antibody response in Peyer's patches to the orally administered dietary protein antigen.

To understand local antibody production to dietary protein antigens in the gut, the reactivity of the monoclonal antibodies (mAbs) from Peyer's patches of BALB/c mice raised against orally administered hen egg lysozyme (HEL) was studied. These mAbs were of IgG1 (7 clones), IgA (5 clones) and IgM (13 clones) isotypes. Some of the HEL-binding mAbs preferentially reacted with reduced, carboxy-methylated HEL, rather than with native HEL. MAbs of the IgA and IgM isotypes had cross-reactivity with other unrelated environmental antigens such as E. coli, single-strand DNA, and soluble components of mouse food. In contrast, the IgG1 mAbs did not cross-react with these antigens. The average of the Kd values for HEL of these mAbs was in the order of 10(-6) M, which is moderately higher than those of mAbs from the preimmune repertoire. These results suggest that, under normal physiological conditions, orally administered dietary proteins predominantly induce the local production of polyreactive IgA/IgM antibodies cross-reacting with environmental luminal antigens.