The effect of immunization of heifers against alpha 1-26 inhibin conjugate on the superovulatory response to pFSH

A total of 121 heifers was blocked by time and diet and then randomly assigned, within block, to an inhibin-immunized (I) or a control (C) group. Immunized heifers (n = 61) received a primary immunization (Day 0) with 0.33 mg of an alpha 1-26 bovine inhibin fragment-human serum albumin (HSA) conjugate injected with non-ulcerative Freund's and DEAE-dextran adjuvants. Booster injections were given on Days 28 and 56. Control heifers (n = 60) received HSA and adjuvants. On Days 56 and 83 the ovaries of heifers were examined by ultrasound to determine the ovulation rate, and blood samples were collected for antibody titer determination. On Day 84, 61 heifers (C, n = 30; I, n = 31) received a total of 24 mg of porcine follicle stimulating hormone (pFSH), while 60 heifers (C, n = 30; I, n = 30) received 12 mg im pFSH, which was administered twice daily for 4 d in decreasing doses during the mid-luteal phase of the estrous cycle. Luteolysis was induced with prostaglandin F(2alpha) analog. The heifers were artificially inseminated and were slaughtered 7 d after estrus. Embryos were recovered and morphologically graded on a scale of 1 to 5 (1 = excellent; 5 = degenerated). Antibody titers (percentage binding at 1:125 serum dilution) differed (P < 0.01) between Group C and I heifers at Days 56 (0.1 vs 30%) and 83 (0.2 vs 37%), and 26% of Group I and 1% of Group C heifers (P < 0.01) had twin ovulations on Day 83. The mean number of embryos recovered was reduced (P = 0.02) in Group I heifers (8.9 +/- 1.2) compared with C heifers (12.1 +/- 1.1); however, the mean number of freezable embryos (Grades 1 and 2) was not affected (P = 0.61) by immunization, and there was no interaction with pFSH (P = 0.36). Ovulation rate as well as embryo yield and quality were not different (P > 0.10) between Group C and I heifers when 12 mg pFSH were administered; however, immunization decreased the superovulatory response to 24 mg of pFSH.     

Monensin and brefeldin A differentially affect the phosphorylation and sulfation of secretory proteins.

Chromogranin B and secretogranin II, two members of the granin family, are known to be post-translationally modified by the addition of O-linked carbohydrates to serine and/or threonine, phosphate to serine and threonine, and sulfate to carbohydrate and tyrosine residues. In the present study, chromogranin B and secretogranin II were used as model proteins to investigate in which subcompartment of the Golgi complex secretory proteins become phosphorylated. Monensin, a drug known to block the transport from the medial to the trans cisternae of the Golgi stack, inhibited the phosphorylation of the granins, indicating that this modification occurred distal to the medial Golgi. Monensin also blocked the addition of galactose to O-linked carbohydrates and the sulfation of the granins, confirming previous data that these modifications take place in the trans Golgi. To distinguish, within the trans Golgi, between the trans cisternae of the Golgi stack and the trans Golgi network, we made use of the previous observation that brefeldin A results in the redistribution to the endoplasmic reticulum of membrane-bound enzymes of the trans cisternae of the Golgi stack, but not of the trans Golgi network. Brefeldin A treatment abolished granin sulfation but resulted in the accumulation of phosphorylated and galactosylated granins. Differential effects of brefeldin A on membranes of the Golgi stack versus the trans Golgi network were also observed by immunofluorescence analysis of marker proteins specific for either compartment. Our results suggest that the phosphorylation of secretory proteins, like their galactosylation, largely occurs in the trans cisternae of the Golgi stack, whereas the sulfation of secretory proteins on both carbohydrate and tyrosine residues takes place selectively in the trans Golgi network.     

Molecules involved in the adhesion and cytotoxicity of activated monocytes on endothelial cells.

Our study was designed to investigate the surface molecules involved in the adhesion and cytotoxicity of activated human monocytes on resting and IL-1-stimulated endothelial cells (EC). Monocytes, exposed to the prototypic activating stimuli IFN-gamma and LPS, showed increased binding to resting and IL-1-treated EC. Activated monocytes were cytotoxic for resting and IL-1-treated EC in a 24- to 48-h [3H]TdR release assay. Anti-CD18 mAb significantly inhibited binding of monocytes on EC: in particular they caused 59 and 22% inhibition of adhesion of activated monocytes to resting and IL-1-stimulated EC, respectively. Anti-VLA4 mAb had little or no effect on binding when used alone, but combined use with anti-CD18 revealed an important role for this adhesion pathway: in particular, VLA4-dependent adhesion accounted for 40% of the binding of activated monocytes on IL-1-treated EC. Anti-CD18 mAb caused similar inhibition (77 and 81%) of the cytotoxicity of activated monocytes on resting and IL-1-treated EC in spite of the fact that this pathway accounted for only 22% of binding to activated EC. Moreover, anti-VLA4 mAb, alone or in combination with anti-CD18, had no effect on cytotoxicity. These results suggest that adhesion of activated monocytes to activated EC involves the CD18- and VLA4-dependent pathways, but that the former is dominant for the expression of cytotoxicity. Thus, in the ensemble of adhesion molecules available for interaction between endothelium and activated monocytes, the hierarchy of their importance may vary for different functions.     

IL-1F5 mediates anti-inflammatory activity in the brain through induction of IL-4 following interaction with SIGIRR/TIR8

Similarity in structure and sequence homology has led to the identification of new members of the interleukin-1 (IL-1) ligand and receptor superfamilies. IL-1F6, IL-1F8 and IL-1F9 have been shown to signal through IL-1R-related protein 2 and IL-1 receptor accessory protein leading to activation of NFκB, while IL-1F7 and IL-1F10 interact with the IL-18 receptor and the soluble IL-1 receptor type I respectively. In contrast, identification of a biological role for IL-1F5 has remained elusive, with conflicting data relating to its possible ability to antagonize IL-1F9-stimulated activation of NFκB in Jurkat cells transfected with IL-1R-related protein 2. In this study, we set out to investigate a possible role for IL-1F5 in the brain and report that it antagonizes the inflammatory effects of IL-1β and lipopolysaccharide (LPS) in vivo and in vitro including the inhibitory effect on long-term potentiation (LTP) in rat hippocampus. We demonstrate that IL-1F5 induces IL-4 mRNA and protein expression in glia in vitro and enhances hippocampal expression of IL-4 following intracerebroventricular (i.c.v.) injection. The inhibitory effect of IL-1F5 on LPS-induced IL-1β is attenuated in cells from IL-4-defective (IL−4^−/− mice). Our findings suggest that IL-1F5 mediates anti-inflammatory effects through its ability to induce IL-4 production and that this is a consequence of its interaction with the orphan receptor, single Ig IL-1R-related molecule (SIGIRR)/TIR8, as the effects were not observed in SIGIRR^−/− mice. In contrast to its effects in brain tissue, IL-1F5 did not attenuate LPS-induced changes, or up-regulated IL-4 in macrophages or dendritic cells, suggesting that the effect is confined to the brain.     

Genetic structure and mating system of Euterpe edulis Mart. Populations: a comparative analysis using microsatellite and allozyme markers

A comparative study between microsatellite and allozyme markers was conducted on the genetic structure and mating system in natural populations of Euterpe edulis Mart. Three cohorts, including seedlings, saplings, and adults, were examined in 4 populations using 10 allozyme loci and 10 microsatellite loci. As expected, microsatellite markers had a much higher degree of polymorphism than allozymes, but estimates of multilocus outcrossing rate ( = 1.00), as well as estimates of genetic structure (F(IS), G(ST)), were similar for the 2 sets of markers. Estimates of R(ST), for microsatellites, were higher than those of G(ST), but results of both statistics revealed a close agreement for the genetic structure of the species. This study provides support for the important conclusion that allozymes are still useful and reliable markers to estimate population genetic parameters. Effects of sample size on estimates from hypervariable loci are also discussed in this paper.     

Protective effects of β-glucan extracted from Agaricus brasiliensis against chemically induced DNA damage in human lymphocytes

β-Glucans (BGs) are polysaccharides that are found in the cell walls of organisms such as bacteria, fungi, and some cereals. The objective of the present study was to investigate the genotoxic and antigenotoxic effects of BG extracted from the mushroom Agaricus brasiliensis (= Agaricus blazei Murrill ss. Heinemann). The mutagenic activity of BG was tested in single-cell gel electrophoresis assays with human peripheral lymphocytes. In addition, the protective effects against the cooked food mutagen 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) and (+/−)-anti-B[a]P-7,8-dihydrodiol-9,10-epoxide (BPDE), which is the main metabolite of B[a]P, and against ROS (H₂O₂)-induced DNA damage, were studied. The results showed that the compound itself was devoid of mutagenic activity, and that a significant dose-dependent protective effect against damage induced by hydrogen peroxide and Trp-P-2 occurred in the dose range 20–80 μg/ml. To investigate the prevention of Trp-P-2-induced DNA damage, a binding assay was carried out to determine whether BG inactivates the amine via direct binding. Since no such interactions were observed, it is likely that BG interacts with enzymes involved in the metabolism of the amine.