Borna disease virus RNA detected in Japanese macaques (Macaca fuscata)

We have examined the seroprevalence of BDV in wild Japanese macaques (Macaca fuscata) in the peninsula (Chiba prefecture), Japan. Serum samples from macaques were examined by the ELISA, Western blot and immunofluorescence assays to detect the presence of serum antibodies that react specifically to BDV antigens. Among 49 investigated individuals, 6 (12.2%) showed positive reaction to BDV antigens. RT-PCR studies detected BDV sequences in brain tissue of one case among four seropositive cases examined. Sequence analysis revealed a high degree of genetic conservation between BDV sequences derived from Japanese macaques and those documented for other animal species. Nevertheless, phylogenetic analysis revealed unique differences between macaque and other species derived BDV sequences.     

Vaccination-induced systemic autoimmunity in farmed Atlantic salmon

Over half of the salmon consumed globally are farm-raised. The introduction of oil-adjuvanted vaccines into salmon aquaculture made large-scale production feasible by preventing infections. The vaccines that are given i.p. contain oil adjuvant such as mineral oil. However, in rodents, a single i.p. injection of adjuvant hydrocarbon oil induces lupus-like systemic autoimmune syndrome, characterized by autoantibodies, immune complex glomerulonephritis, and arthritis. In the present study, whether the farmed salmon that received oil-adjuvanted vaccine have autoimmune syndrome similar to adjuvant oil-injected rodents was examined. Sera and tissues were collected from vaccinated or unvaccinated Atlantic salmon (experimental, seven farms) and wild salmon. Autoantibodies (immunofluorescence, ELISA, and immunoprecipitation) and IgM levels (ELISA) in sera were measured. Kidneys and livers were examined for pathology. Autoantibodies were common in vaccinated fish vs unvaccinated controls and they reacted with salmon cells/Ags in addition to their reactivity with mammalian Ags. Diffuse nuclear/cytoplasmic staining was common in immunofluorescence but some had more specific patterns. Serum total IgM levels were also increased in vaccinated fish; however, the fold increase of autoantibodies was much more than that of total IgM. Sera from vaccinated fish immunoprecipitated ferritin and approximately 50% also reacted with other unique proteins. Thrombosis and granulomatous inflammation in liver, and immune-complex glomerulonephritis were common in vaccinated fish. Autoimmunity similar to the mouse model of adjuvant oil-induced lupus is common in vaccinated farmed Atlantic salmon. This may have a significant impact on production loss, disease of previously unknown etiology, and future strategies of vaccines and salmon farming.     

Inhibitory effect of chicken gonadotropin-releasing hormone II on food intake in the goldfish, Carassius auratus

Gonadotropin-releasing hormone (GnRH) is an evolutionarily conserved neuropeptide with 10 amino acid residues, which possesses some structural variants. A molecular form known as chicken GnRH II ([His⁵ Trp⁷ Tyr⁸] GnRH, cGnRH II) is widely distributed in vertebrates, and has recently been implicated in the regulation of sexual behavior and food intake in an insectivore, the musk shrew. However, the influence of cGnRH II on feeding behavior has not yet been studied in model animals such as rodents and teleost fish. In this study, therefore, we investigated the role of cGnRH II in the regulation of feeding behavior in the goldfish, and examined its involvement in food intake after intracerebroventricular (ICV) administration. ICV-injected cGnRH II at graded doses, from 0.1 to 10 pmol/g body weight (BW), induced a decrease of food consumption in a dose-dependent manner during 60 min after treatment. Cumulative food intake was significantly decreased by ICV injection of cGnRH II at doses of 1 and 10 pmol/g BW during the 60-min post-treatment observation period. ICV injection of salmon GnRH ([Trp⁷ Leu⁸] GnRH, sGnRH) at doses of 0.1-10 pmol/g BW did not affect food intake. The anorexigenic action of cGnRH II was completely blocked by treatment with the GnRH type I receptor antagonist, Antide. However, the anorexigenic action of cGnRH II was not inhibited by treatment with the corticotropin-releasing hormone (CRH) 1/2 receptor antagonist, α-helical CRH₍₉₋₄₁₎, and the melanocortin 4 receptor antagonist, HS024. These results suggest that, in the goldfish, cGnRH II, but not sGnRH, acts as an anorexigenic factor, as is the case in the musk shrew, and that the anorexigenic action of cGnRH II is independent of CRH- and melanocortin-signaling pathways.     

Alpha-melanocyte-stimulating hormone mediates melanin-concentrating hormone-induced anorexigenic action in goldfish

In goldfish, intracerebroventricular (ICV) administration of melanin-concentrating hormone (MCH) inhibits feeding behavior, and fasting decreases hypothalamic MCH-like immunoreactivity. However, while MCH acts as an anorexigenic factor in goldfish, in rodents MCH has an orexigenic effect. Therefore, we examined the involvement of two anorexigenic neuropeptides, alpha-melanocyte-stimulating hormone (alpha-MSH) and corticotropin-releasing hormone (CRH), in the anorexigenic action of MCH in goldfish, using an alpha-MSH receptor antagonist, HS024, and a CRH receptor antagonist, alpha-helical CRH((9-41)). ICV injection of HS024, but not alpha-helical CRH((9-41)), suppressed MCH-induced anorexigenic action for a 60-min observation period. We then examined, using a real-time PCR method, whether MCH affects the levels of mRNAs encoding various orexigenic neuropeptides, including neuropeptide Y (NPY), orexin, ghrelin and Agouti-related peptide (AgRP), in the goldfish diencephalon. ICV administration of MCH at a dose sufficient to inhibit food consumption decreased the expression of mRNAs for NPY and ghrelin, but not for orexin and AgRP. These results indicate that the anorexigenic action of MCH in the goldfish brain is mediated by the alpha-MSH signaling pathway and is accompanied by inhibition of NPY and ghrelin synthesis.     

Involvement of highly sulfated chondroitin sulfate in the metastasis of the Lewis lung carcinoma cells

The altered expression of cell surface chondroitin sulfate (CS) and dermatan sulfate (DS) in cancer cells has been demonstrated to play a key role in malignant transformation and tumor metastasis. However, the functional highly sulfated structures in CS/DS chains and their involvement in the process have not been well documented. In the present study, a structural analysis of CS/DS from two mouse Lewis lung carcinoma (3LL)-derived cell lines with different metastatic potentials revealed a higher proportion of Delta(4,5)HexUA-GalNAc(4,6-O-disulfate) generated from E-units (GlcUA-GalNAc(4, 6-O-disulfate)) in highly metastatic LM66-H11 cells than in low metastatic P29 cells, although much less CS/DS is expressed by LM66-H11 than P29 cells. This key finding prompted us to study the role of CS-E-like structures in experimental lung metastasis. The metastasis of LM66-H11 cells to lungs was effectively inhibited by enzymatic removal of tumor cell surface CS or by preadministration of CS-E rich in E-units in a dose-dependent manner. In addition, immunocytochemical analysis showed that LM66-H11 rather than P29 cells expressed more strongly the CS-E epitope, which was specifically recognized by the phage display antibody GD3G7. More importantly, this antibody and a CS-E decasaccharide fraction, the minimal structure recognized by GD3G7, strongly inhibited the metastasis of LM66-H11 cells probably by modifying the proliferative and invading behavior of the metastatic tumor cells. These results suggest that the E-unit-containing epitopes are involved in the metastatic process and a potential target for the diagnosis and treatment of malignant tumors.     

Neuronal interaction between melanin-concentrating hormone- and alpha-melanocyte-stimulating hormone-containing neurons in the goldfish hypothalamus

Intracerebroventricular (ICV) administration of melanin-concentrating hormone (MCH) inhibits food intake in goldfish, unlike in rodents, suggesting that its anorexigenic action is mediated by alpha-melanocyte-stimulating hormone (alpha-MSH) but not corticotropin-releasing hormone. This led us to investigate whether MCH-containing neurons in the goldfish brain have direct inputs to alpha-MSH-containing neurons, using a confocal laser scanning microscope, and to examine whether the anorexigenic action of MCH is also mediated by other anorexigenic neuropeptides, such as cholecystokinin (CCK) and pituitary adenylate cyclase-activating polypeptide (PACAP), using their receptor antagonists. MCH- and alpha-MSH-like immunoreactivities were distributed throughout the brain, especially in the diencephalon. MCH-containing nerve fibers or endings lay in close apposition to alpha-MSH-containing neurons in the hypothalamus in the posterior part of the nucleus lateralis tuberis (NLTp). The inhibitory effect of ICV-injected MCH on food intake was not affected by treatment with a CCK A/CCK B receptor antagonist, proglumide, or a PACAP receptor (PAC(1) receptor) antagonist, PACAP((6-38)). ICV administration of MCH at a dose sufficient to inhibit food consumption also did not influence expression of the mRNAs encoding CCK and PACAP. These results strongly suggest that MCH-containing neurons provide direct input to alpha-MSH-containing neurons in the NLTp of goldfish, and that MCH plays a crucial role in the regulation of feeding behavior as an anorexigenic neuropeptide via the alpha-MSH (melanocortin 4 receptor)-signaling pathway.     

Outer Membrane Vesicles of Helicobacter pylori TK1402 are Involved in Biofilm Formation

Background  

Helicobacter pylori forms biofilms on glass surfaces at the air-liquid interface in in vitro batch cultures; however, biofilms of H. pylori have not been well characterized. In the present study, we analyzed the ability of H. pylori strains to form biofilms and characterized the underlying mechanisms of H. pylori biofilm formation.     

Atrial natriuretic peptide and cGMP activate sodium transport through PKA-dependent pathway in the urinary bladder of the Japanese tree frog

The effects of atrial natriuretic peptide (ANP) and cGMP on transepithelial ion transport were examined in the urinary bladder of the Japanese tree frog, Hyla japonica, using Ussing chamber voltage-clamp and whole-cell patch-clamp techniques. When the bladders were exposed to 4.4×10⁻¹¹ to 10⁻⁶ M ANP or 10⁻⁷ to 3×10⁻⁴ M 8-Br-cGMP, both the transepithelial potential difference (PD) and the short-circuit current (Isc) were significantly increased in a concentration-response manner. The cGMP-dependent responses were inhibited in a Na⁺-free bath solution and in the presence of amiloride. The cGMP-dependent increases in Isc were significantly inhibited by specific PKA inhibitors (5×10⁻⁷ M KT-5720 and >10⁻⁵ M H-89), but not by a specific PKG inhibitor (5×10⁻⁷ M KT-5823). ANP-dependent increases in Isc were also significantly inhibited by KT-5720. In the patch-clamp study, ANP and cGMP significantly increased in inward currents involving Na⁺ uptake. These results suggest that a cross-talk mechanism exists between cAMP and cGMP signaling pathways, which leads to Na⁺ transport in the frog urinary bladder. In addition, the cGMP-dependent increases in Isc were partially inhibited by 10⁻⁴ M l-cis-diltiazem, a specific inhibitor of cyclic nucleotide-gated (CNG) channels. These results also suggest a relation between CNG channels and the cGMP-dependent increases in Na⁺ absorption of the frog urinary bladder.     

Interaction of aliphatic cap group in inhibition of histone deacetylases by cyclic tetrapeptides

Inhibitors of histone deacetylases (HDACs) are a promising class of anticancer agents that effect gene regulation. To know the interaction of aliphatic cap groups with HDACs, cyclic tetrapeptide and bicyclic peptide disulfide hybrids were synthesized without aromatic ring in their macrocyclic framework. Benzene ring of l-Phe in chlamydocin was replaced with several aliphatic amino acids and also a fused bicyclic tetrapeptide was synthesized by ring closing metathesis using Grubb's first generation catalyst. The inhibitory activities of the cyclic peptides against histone deacetylase enzymes were evaluated, which demonstrated most of them are interesting candidates as anticancer agents.