Abstracts from the 8th International Conference on cGMP Generators, Effectors and Therapeutic Implications

This work was supported by a restricted research grant of Bayer AG

Involvement of Peripheral Monocytes with IL-1β in the Pathogenesis of West Syndrome

Neuroinflammation has been implicated in the pathogenesis of West syndrome (WS). Inflammatory cytokines, including interleukin-1β(IL-1β), have been reported to be associated with epilepsy. However, the assessment of cytokine changes in humans is not always simple or deterministic. This study aimed to elucidate the immunological mechanism of WS. We examined the intracellular cytokine profiles of peripheral blood cells collected from 13 patients with WS, using flow cytometry, and measured their serum cytokine levels. These were compared with those of 10 age-matched controls. We found that the WS group had significantly higher percentages of inter IL-1β, interleukin-1 receptor antagonist (IL-1RA)-positive monocytes, and interferon gamma (IFN-γ) in their CD8+ T cells than the control group. Interestingly, the group with sequelae revealed significantly lower levels of intracellular IFN-γ and IL-6 in their CD8+ T and CD4+ T cells, respectively, than the group without sequelae. There was no correlation between the ratios of positive cells and the serum levels of a particular cytokine in the WS patients. These cytokines in the peripheral immune cells might be involved in the neuroinflammation of WS, even in the absence of infectious or immune disease. Overall, an immunological approach using flow cytometry analysis might be useful for immunological studies of epilepsy

Identification of Sialylated Glycoproteins in Doxorubicin-Treated Hepatoma Cells with Glycoproteomic Analyses

Sialylation is one of the most important types of glycosylation involved in carcinogenesis and establishment of cancer stemness. We previously showed that increased sialylation is a characteristic glycan change in cancer stem cells (CSCs) from hepatocellular carcinoma. However, the identities of glycoproteins targeted for sialylation remain unknown. In the present study, we identified glycoproteins targeted for sialylation in doxorubicin (DXR)-treated hepatocarcinoma cell line, Huh7, using glycoproteomic analyses. Since CSCs constitute a small subset of cells within carcinoma cell lines, it is difficult to identify sialylated proteins using general glycoproteomic strategies. It is known that treatment with anticancer drug can condense CSCs, we used DXR to concentrate CSCs. In DXR-treated Huh7 cells, isobaric tag for relative and absolute quantitation (iTRAQ) analysis identified 17 sialylated glycoproteins. Most of the identified glycoproteins were cancer-associated proteins. Furthermore, two proteins of approximately 70 kDa were detected using <i>Sambucus sieboldoana</i> agglutinin (SSA) blot analysis and identified as beta-galactosidase and alpha-2-HS-glycoprotein (fetuin-A) by SSA precipitation followed by liquid chromatography-tandem mass spectrometry analyses. Sialylation levels of fetuin-A were increased in DXR-treated Huh7 cell lysates. These changes in sialylation of glycoproteins might be involved in the establishment of cancer stemness

Identification of Sialylated Glycoproteins in Doxorubicin-Treated Hepatoma Cells with Glycoproteomic Analyses

Sialylation is one of the most important types of glycosylation involved in carcinogenesis and establishment of cancer stemness. We previously showed that increased sialylation is a characteristic glycan change in cancer stem cells (CSCs) from hepatocellular carcinoma. However, the identities of glycoproteins targeted for sialylation remain unknown. In the present study, we identified glycoproteins targeted for sialylation in doxorubicin (DXR)-treated hepatocarcinoma cell line, Huh7, using glycoproteomic analyses. Since CSCs constitute a small subset of cells within carcinoma cell lines, it is difficult to identify sialylated proteins using general glycoproteomic strategies. It is known that treatment with anticancer drug can condense CSCs, we used DXR to concentrate CSCs. In DXR-treated Huh7 cells, isobaric tag for relative and absolute quantitation (iTRAQ) analysis identified 17 sialylated glycoproteins. Most of the identified glycoproteins were cancer-associated proteins. Furthermore, two proteins of approximately 70 kDa were detected using <i>Sambucus sieboldoana</i> agglutinin (SSA) blot analysis and identified as beta-galactosidase and alpha-2-HS-glycoprotein (fetuin-A) by SSA precipitation followed by liquid chromatography-tandem mass spectrometry analyses. Sialylation levels of fetuin-A were increased in DXR-treated Huh7 cell lysates. These changes in sialylation of glycoproteins might be involved in the establishment of cancer stemness

Role of Neuroinflammation and Blood-Brain Barrier Permutability on Migraine

Currently, migraine is treated mainly by targeting calcitonin gene-related peptides, although the efficacy of this method is limited and new treatment strategies are desired. Neuroinflammation has been implicated in the pathogenesis of migraine. In patients with migraine, peripheral levels of pro-inflammatory cytokines, such as interleukin-1β (IL-1β) and tumor necrosis factor-α, are known to be increased. Additionally, animal models of headache have demonstrated that immunological responses associated with cytokines are involved in the pathogenesis of migraine. Furthermore, these inflammatory mediators might alter the function of tight junctions in brain vascular endothelial cells in animal models, but not in human patients. Based on clinical findings showing elevated IL-1β, and experimental findings involving IL-1β and both the peripheral trigeminal ganglion and central trigeminal vascular pathways, regulation of the Il-1β/IL-1 receptor type 1 axis might lead to new treatments for migraine. However, the integrity of the blood-brain barrier is not expected to be affected during attacks in patients with migraine

The NPC Motif of Aquaporin-11, Unlike the NPA Motif of Known Aquaporins, Is Essential for Full Expression of Molecular Function*

The recently identified molecule aquaporin-11 (AQP11) has a unique amino acid sequence pattern that includes an Asn-Pro-Cys (NPC) motif, corresponding to the N-terminal Asn-Pro-Ala (NPA) signature motif of conventional AQPs. In this study, we examined the effect of the mutation of the NPC motif on the subcellular localization, oligomerization, and water permeability of AQP11 in transfected mammalian cells. Furthermore, the effect was also assessed using zebrafish. Site-directed mutation at the NPC motif did not affect the subcellular localization of AQP11 but reduced its oligomerization. A cell swelling assay revealed that cells expressing AQP11 with a mutated NPC motif had significantly lower osmotic water permeability than cells expressing wild-type AQP11. Zebrafish deficient in endogenous AQP11 showed a deformity in the tail region at an early stage of development. This phenotype was dramatically rescued by injection of human wild-type AQP11 mRNA, whereas the effect of mRNA for AQP11 with a mutated NPC motif was less marked. Although the NPA motif is known to be important for formation of water-permeable pores by conventional AQPs, our observations suggest that the corresponding NPC motif of AQP11 is essential for full expression of molecular function