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Roland Schauer - One of the best experts on this subject based on the ideXlab platform.
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Sialic Acids as link to Japanese scientists
Proceedings of the Japan Academy. Series B Physical and biological sciences, 2016Co-Authors: Roland SchauerAbstract:This manuscript is dedicated to Prof. Tamio Yamakawa and describes my cooperations on Sialic acid-related topics with Japanese scientists during the last 40 years. We studied Sialic Acids and their O-acetylated derivatives in the sea urchin Pseudocentrotus depressus, in Halocynthia species, and in human and bovine milk. In seafood we mainly searched for N-glycolylneuraminic acid. With synthetic substrates it was shown that Sialic acid O-acetylation at C-4 hinders the activity of sialidases, with the exception of viral enzymes. The biosynthesis of Neu5Gc was discussed and the distribution of this Sialic acid in dogs followed in modern literature and reviewed regarding their migration. An excellent source of Sialic Acids is edible bird nest substance (Collocalia mucin) which was used for the synthesis of sialylation inhibitors.
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o acetylated Sialic Acids and their role in immune defense
Advances in Experimental Medicine and Biology, 2011Co-Authors: Roland Schauer, Vinayaga G Srinivasan, Dirk Wipfler, Bernhard Kniep, Reinhard SchwartzalbiezAbstract:The expression of Sialic Acids (Sia) is highly conserved in deuterostomes, i.e., from echinoderms to humans. They constitute components of cell surface glycoproteins and gangliosides, where they occupy mainly the terminal position as individual monosaccharides and, more rarely, as oligo- or polymers. They are frequently found in secreted glycoconjugates and in oligosaccharides, mainly of blood serum, milk, and mucus secretions [1, 2].
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Chemistry, Metabolism, and Biological Functions of Sialic Acids
Advances in Carbohydrate Chemistry and Biochemistry, 2008Co-Authors: Roland SchauerAbstract:Publisher Summary This chapter discusses the chemistry, metabolism, and biological functions of Sialic Acids. Interest in the Sialic Acids has rapidly increased in recent years, especially because of the reorganization of their involvement in the regulation of a great variety of biological phenomena. The occurrence of Sialic Acids in plants has never unequivocally been established, although some positive reports exist. The acylneuraminic Acids can be released from their glycosidic linkages either by dilute (aqueous or methanolic) Acids or sialidases. The unequivocal determination of Sialic Acids occurring in low concentrations in many biological materials is rather difficult, and this explains the many errors that have been made in this field. The biosynthesis of N-acetylneuraminic acid (Neu5Ac) is briefly reported in this chapter and more attention is given to the enzyme reactions modifying this compound. Little information is available about the role of the modifications of Sialic acid resulting in a species- and tissue-specific distribution of different N,O-acylated and O-methylated Sialic Acids.
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analysis of monosaccharides fatty constituents and rare o acetylated Sialic Acids from gonads of the starfish asterias rubens
Biochimie, 2006Co-Authors: Jeanpierre Zanetta, Vinayaga Srinivasan, Roland SchauerAbstract:A previous study (Bergwerff et al., Biochimie 74 (1992) 25‐37) reported that Sialic Acids present in Asterias rubens gonads were essentially composed of 8-methyl-N-glycolylneuraminic acid (Neu5Gc8Me), a large part of it being acetylated in position 9. Using GC/MS of heptafluorobutyrate derivatives (Zanetta et al., Glycobiology 11 (2001) 663‐676) on the chloroform/methanol soluble and insoluble fractions, we showed that most Sialic Acids were found in the latter and demonstrated that all Sialic Acids were derived from N-glycolylneuraminic acid, most of them being 8-methylated, but that the majority were also acetylated in position 4 or 7 (or both positions). GC/MS analyses of the constituents liberated using acid-catalysed methanolysis verified that major glycoprotein-bound glycans were N-linked and of the gluco-oligomannosidic type. Major fatty Acids were poly-unsaturated (especially C20:4) and long-chain bases were C22:1 phytosphingosine and C22:2 6-hydroxysphingenine. Major monosaccharides found in the chloroform/methanol extract (quinovose and fucose) were derived from steroidal saponins. © 2005 Elsevier SAS. All rights reserved.
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Sialic Acids fascinating sugars in higher animals and man
Zoology, 2004Co-Authors: Roland SchauerAbstract:Sialic Acids are acidic monosaccharides, which are among the most important molecules of higher animals, and occur in some microorganisms. They are bound to complex carbohydrates and occupy prominent positions, especially in cell membranes. Their structural diversity is high and, correspondingly, the mechanisms for their biosynthesis are complex. Sialic acid substituents strongly influence the activity of catabolic enzymes, in particular the sialidases, and thus the turnover rate of glycoconjugates. These sugars are involved in manifold cell functions. Due to the surface location of the acidic molecules they shield macromolecules and cells from enzymatic and immunological attacks. But they also represent recognition sites for various physiological receptors as well as for toxins and microorganisms, and thus allow their colonization. Many viruses use Sialic Acids for the infection of cells. As Sialic Acids also play a decisive role in tumor biology they prove to be rather versatile molecules that modulate cell biological events in a sensitive way. It is discussed that their evolvement may have stimulated evolution and rendered organisms less vulnerable to environmental attacks. However, disturbance of their metabolism may cause diseases.
Azuma Tsukise - One of the best experts on this subject based on the ideXlab platform.
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Histochemical distribution of Sialic Acids and antimicrobial substances in porcine carpal glands
Archives of Dermatological Research, 2012Co-Authors: Kousuke Fukui, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Hiroshi Gomi, Hiroshi Sugiya, Azuma TsukiseAbstract:The localization of Sialic Acids and antimicrobial products (lysozyme, IgA, lactoferrin, β-defensin 2) as well as Rab3D in the carpal glands of pig was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium of the carpal glands consisted of dark and clear cells. The dark cells of these glands exhibited high levels of sialoglycoconjugates, including O -acetylated Sialic Acids, whereas the localization of Sialic Acids linked to α2-3Gal1-4GlcNAc was confined to a subpopulation of the dark cells. Furthermore, all antimicrobial substances and Rab3D were mainly detectable in a subpopulation of the dark cells. The results obtained are discussed with regard to the functional significance of these glands. Our findings suggested that Rab3D is involved in the secretory regulation of sialoglycoconjugates and antimicrobial substances. These secretory products may create a defensive barrier against microbial invasion and play an essential role in the preservation of skin integrity.
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Sialic Acids and antimicrobial substances in the apocrine glands of porcine perianal skin
Archives of Dermatological Research, 2012Co-Authors: Takayuki Nara, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Azuma TsukiseAbstract:The porcine perianal skin shows prominent apocrine glands with large saccular dilatations, whereby the functional significance of the glandular secretions is rather unexplained. Our study focuses on the demonstration of sialoglycoconjugates and antimicrobial substances in these glands, using glycoconjugate histochemical and immunohistochemical methods. The result obtained emphasized the general presence of Sialic Acids, linked to α2-6Gal/GalNAc and α2-3Gaβl1-4GlcNAc, in the secretory cells. The secretory epithelium and luminal secretions also contained a spectrum of antimicrobial substances, such as lysozyme, IgA, lactoferrin, and the peptide group of β-defensins. Realizing that Sialic Acids possess diverging functional properties through various saccharide residues, and that antimicrobial substances serve as a non-specific defense against microorganisms, these secretory products may function as protective agents in order to preserve the integrity of the perianal region. This view includes that the amounts of bacteria on the skin surface are controlled and maintained at the certain level.
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Histochemical localization of Sialic Acids and antimicrobial substances in eccrine glands of porcine snout skin.
European Journal of Histochemistry, 2012Co-Authors: Kousuke Fukui, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Hiroshi Gomi, Hiroshi Sugiya, Azuma TsukiseAbstract:The distribution of Sialic Acids and antimicrobial products (lysozyme, IgA, lactoferrin, β-defensin 2) as well as Rab3D in the eccrine glands of porcine snout skin was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium consisted of two types of secretory cells: dark and clear cells. The dark cells exhibited considerable amounts of sialoglycoconjugates, which included O-acetylated Sialic Acids, whereas Sialic Acids in the sequence Siaα-2-3Gal1-4GlcNAc were confined to some of the dark cells. All antimicrobial substances and Rab3D were demonstrated to be also mainly present in some of the dark cells. Additionally, in the cytological and cytochemical features, the different characteristics were observed among the dark cells. The results obtained are discussed with regard to the functional significance of the eccrine glands. The secretory products elaborated by this gland type may function as protective agents in order to preserve the skin integrity of the snout region, considering that Sialic Acids and antimicrobial substances are important in general defense mechanisms.
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Histochemical properties of Sialic Acids and antimicrobial substances in canine anal glands
European Journal of Histochemistry, 2011Co-Authors: Takayuki Nara, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Azuma TsukiseAbstract:The functional properties of Sialic Acids appear to be manifold. Additionally, antimicrobial substances serve as a non-specific defense against microorganisms. In this study, therefore, the localization of Sialic Acids and antimicrobial substances in the anal glands of dog was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium, luminal secretions and excretory ducts exhibited high levels of sialoglycoconjugates that terminated in Siaα2-6Gal/GalNAc or Siaα2-3Gal1-4GlcNAc. Additionally, O-acetylated Sialic Acids were detectable in these glandular structures. Antimicrobial substances, such as lysozyme, immunoglobulin A (IgA), lactoferrin and the peptide group of β-defensins, were also demonstrated as products of the anal glands. The results obtained are discussed with regard to the functional significance of the anal glands. These secretory products may create a defensive barrier against microbial invasion at the anal mucosa.
Osamu Fujimori - One of the best experts on this subject based on the ideXlab platform.
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Histochemical distribution of Sialic Acids and antimicrobial substances in porcine carpal glands
Archives of Dermatological Research, 2012Co-Authors: Kousuke Fukui, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Hiroshi Gomi, Hiroshi Sugiya, Azuma TsukiseAbstract:The localization of Sialic Acids and antimicrobial products (lysozyme, IgA, lactoferrin, β-defensin 2) as well as Rab3D in the carpal glands of pig was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium of the carpal glands consisted of dark and clear cells. The dark cells of these glands exhibited high levels of sialoglycoconjugates, including O -acetylated Sialic Acids, whereas the localization of Sialic Acids linked to α2-3Gal1-4GlcNAc was confined to a subpopulation of the dark cells. Furthermore, all antimicrobial substances and Rab3D were mainly detectable in a subpopulation of the dark cells. The results obtained are discussed with regard to the functional significance of these glands. Our findings suggested that Rab3D is involved in the secretory regulation of sialoglycoconjugates and antimicrobial substances. These secretory products may create a defensive barrier against microbial invasion and play an essential role in the preservation of skin integrity.
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Sialic Acids and antimicrobial substances in the apocrine glands of porcine perianal skin
Archives of Dermatological Research, 2012Co-Authors: Takayuki Nara, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Azuma TsukiseAbstract:The porcine perianal skin shows prominent apocrine glands with large saccular dilatations, whereby the functional significance of the glandular secretions is rather unexplained. Our study focuses on the demonstration of sialoglycoconjugates and antimicrobial substances in these glands, using glycoconjugate histochemical and immunohistochemical methods. The result obtained emphasized the general presence of Sialic Acids, linked to α2-6Gal/GalNAc and α2-3Gaβl1-4GlcNAc, in the secretory cells. The secretory epithelium and luminal secretions also contained a spectrum of antimicrobial substances, such as lysozyme, IgA, lactoferrin, and the peptide group of β-defensins. Realizing that Sialic Acids possess diverging functional properties through various saccharide residues, and that antimicrobial substances serve as a non-specific defense against microorganisms, these secretory products may function as protective agents in order to preserve the integrity of the perianal region. This view includes that the amounts of bacteria on the skin surface are controlled and maintained at the certain level.
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Histochemical localization of Sialic Acids and antimicrobial substances in eccrine glands of porcine snout skin.
European Journal of Histochemistry, 2012Co-Authors: Kousuke Fukui, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Hiroshi Gomi, Hiroshi Sugiya, Azuma TsukiseAbstract:The distribution of Sialic Acids and antimicrobial products (lysozyme, IgA, lactoferrin, β-defensin 2) as well as Rab3D in the eccrine glands of porcine snout skin was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium consisted of two types of secretory cells: dark and clear cells. The dark cells exhibited considerable amounts of sialoglycoconjugates, which included O-acetylated Sialic Acids, whereas Sialic Acids in the sequence Siaα-2-3Gal1-4GlcNAc were confined to some of the dark cells. All antimicrobial substances and Rab3D were demonstrated to be also mainly present in some of the dark cells. Additionally, in the cytological and cytochemical features, the different characteristics were observed among the dark cells. The results obtained are discussed with regard to the functional significance of the eccrine glands. The secretory products elaborated by this gland type may function as protective agents in order to preserve the skin integrity of the snout region, considering that Sialic Acids and antimicrobial substances are important in general defense mechanisms.
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Histochemical properties of Sialic Acids and antimicrobial substances in canine anal glands
European Journal of Histochemistry, 2011Co-Authors: Takayuki Nara, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Azuma TsukiseAbstract:The functional properties of Sialic Acids appear to be manifold. Additionally, antimicrobial substances serve as a non-specific defense against microorganisms. In this study, therefore, the localization of Sialic Acids and antimicrobial substances in the anal glands of dog was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium, luminal secretions and excretory ducts exhibited high levels of sialoglycoconjugates that terminated in Siaα2-6Gal/GalNAc or Siaα2-3Gal1-4GlcNAc. Additionally, O-acetylated Sialic Acids were detectable in these glandular structures. Antimicrobial substances, such as lysozyme, immunoglobulin A (IgA), lactoferrin and the peptide group of β-defensins, were also demonstrated as products of the anal glands. The results obtained are discussed with regard to the functional significance of the anal glands. These secretory products may create a defensive barrier against microbial invasion at the anal mucosa.
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Histochemical Studies on Sialic Acids in the Epididymis During Post-natal Development of the Rat
The Histochemical Journal, 1998Co-Authors: Takashi Ueda, Kenji Kajita, Osamu FujimoriAbstract:A variety of Sialic Acids contained in the rat epididymis during post-natal development were examined by means of lectin and carbohydrate histochemistry. Epididymides from male Sprague– Dawley rats on post-natal days 14, 21, 30, 39, 49, 56 and 70 were fixed in Bouin's fluid and embedded routinely in paraffin wax. Hydrated sections were subjected either to the lectin methods using biotinylated Sambucus sieboldiana lectin or Maackia amurensis lectin or to the selective periodate oxidation– phenylhydrazine–thiocarbohydrazide–silver protein–physical development technique with or without saponification. The results revealed that Sialic Acids appeared in the epididymal epithelium at day 14, followed by particular distribution patterns corresponding to cell differentiation during days 21–39. High-level O-acetylation of Sialic Acids was observed in the principal cells of the initial segment and proximal caput after day 39. These results suggest that Sialic Acids with different linkages and O-acetylation become adult in distribution at the ′differentiation′ period under the influence of androgen, before spermatozoa reach the epididymal lumen. Such carbohydrates may be correlated, at least in part, with sperm-binding sialoproteins, which increase dramatically during the window between days 21 and 39.
Xi Chen - One of the best experts on this subject based on the ideXlab platform.
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chemoenzymatic synthesis of c8 modified Sialic Acids and related α2 3 and α2 6 linked sialosides
ChemInform, 2012Co-Authors: Hongzhi Cao, Vinod K Tiwari, Xi ChenAbstract:The Sialic acid aldolase-catalyzed enzymatic approach furnishes four C-8 modified Sialic Acids.
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a sialylated glycan microarray reveals novel interactions of modified Sialic Acids with proteins and viruses
Journal of Biological Chemistry, 2011Co-Authors: Xuezheng Song, Xi Chen, Hongzhi Cao, Vinod K Tiwari, Yi Lasanajak, Mary M Tappert, Gillian M Air, Harshal A Chokhawala, Haojie Zheng, Richard D CummingsAbstract:Many glycan-binding proteins in animals and pathogens recognize Sialic acid or its modified forms, but their molecular recognition is poorly understood. Here we describe studies on Sialic acid recognition using a novel sialylated glycan microarray containing modified Sialic Acids presented on different glycan backbones. Glycans terminating in β-linked galactose at the non-reducing end and with an alkylamine-containing fluorophore at the reducing end were sialylated by a one-pot three-enzyme system to generate α2–3- and α2–6-linked sialyl glycans with 16 modified Sialic Acids. The resulting 77 sialyl glycans were purified and quantified, characterized by mass spectrometry, covalently printed on activated slides, and interrogated with a number of key Sialic acid-binding proteins and viruses. Sialic acid recognition by the Sialic acid-binding lectins Sambucus nigra agglutinin and Maackia amurensis lectin-I, which are routinely used for detecting α2–6- and α2–3-linked Sialic Acids, are affected by Sialic acid modifications, and both lectins bind glycans terminating with 2-keto-3-deoxy-d-glycero-d-galactonononic acid (Kdn) and Kdn derivatives stronger than the derivatives of more common N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc). Three human parainfluenza viruses bind to glycans terminating with Neu5Ac or Neu5Gc and some of their derivatives but not to Kdn and its derivatives. Influenza A virus also does not bind glycans terminating in Kdn or Kdn derivatives. An especially novel aspect of human influenza A virus binding is its ability to equivalently recognize glycans terminated with either α2–6-linked Neu5Ac9Lt or α2–6-linked Neu5Ac. Our results demonstrate the utility of this sialylated glycan microarray to investigate the biological importance of modified Sialic Acids in protein-glycan interactions.
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chemoenzymatic synthesis of c8 modified Sialic Acids and related α2 3 and α2 6 linked sialosides
Bioorganic & Medicinal Chemistry Letters, 2011Co-Authors: Hongzhi Cao, Vinod K Tiwari, Xi ChenAbstract:Abstract Naturally occurring 8- O -methylated Sialic Acids, including 8- O -methyl- N -acetylneuraminic acid and 8- O -methyl- N -glycolylneuraminic acid, along with 8- O -methyl-2-keto-3-deoxy- d -glycero- d -galacto-nonulosonic acid (Kdn8Me) and 8-deoxy-Kdn were synthesized from corresponding 5- O -modified six-carbon monosaccharides and pyruvate using a Sialic acid aldolase cloned from Pasteurella multocida strain P-1059 (PmNanA). In addition, α2–3- and α2–6-linked sialyltrisaccharides containing Neu5Ac8Me and Kdn8Deoxy were also synthesized using a one-pot multienzyme approach. The strategy reported here provides an efficient approach to produce glycans containing various C8-modified Sialic Acids for biological evaluations.
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Advances in the Biology and Chemistry of Sialic Acids
ACS Chemical Biology, 2010Co-Authors: Xi Chen, Ajit VarkiAbstract:Sialic Acids are a subset of nonulosonic Acids, which are nine-carbon α-keto aldonic Acids. Natural existing Sialic acid-containing structures are presented in different Sialic acid forms, various sialyl linkages, and on diverse underlying glycans. They play important roles in biological, pathological, and immunological processes. Sialobiology has been a challenging and yet attractive research area. Recent advances in chemical and chemoenzymatic synthesis, as well as large-scale E. coli cell-based production, have provided a large library of sialoside standards and derivatives in amounts sufficient for structure−activity relationship studies. Sialoglycan microarrays provide an efficient platform for quick identification of preferred ligands for Sialic acid-binding proteins. Future research on Sialic acid will continue to be at the interface of chemistry and biology. Research efforts not only will lead to a better understanding of the biological and pathological importance of Sialic Acids and their diversi...
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Advances in the Biology and Chemistry of Sialic Acids
ACS chemical biology, 2010Co-Authors: Xi Chen, Ajit VarkiAbstract:Sialic Acids are a subset of nonulosonic Acids, which are nine-carbon alpha-keto aldonic Acids. Natural existing Sialic acid-containing structures are presented in different Sialic acid forms, various sialyl linkages, and on diverse underlying glycans. They play important roles in biological, pathological, and immunological processes. Sialobiology has been a challenging and yet attractive research area. Recent advances in chemical and chemoenzymatic synthesis, as well as large-scale E. coli cell-based production, have provided a large library of sialoside standards and derivatives in amounts sufficient for structure-activity relationship studies. Sialoglycan microarrays provide an efficient platform for quick identification of preferred ligands for Sialic acid-binding proteins. Future research on Sialic acid will continue to be at the interface of chemistry and biology. Research efforts not only will lead to a better understanding of the biological and pathological importance of Sialic Acids and their diversity but also could lead to the development of therapeutics.
Wilfried Meyer - One of the best experts on this subject based on the ideXlab platform.
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Histochemical distribution of Sialic Acids and antimicrobial substances in porcine carpal glands
Archives of Dermatological Research, 2012Co-Authors: Kousuke Fukui, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Hiroshi Gomi, Hiroshi Sugiya, Azuma TsukiseAbstract:The localization of Sialic Acids and antimicrobial products (lysozyme, IgA, lactoferrin, β-defensin 2) as well as Rab3D in the carpal glands of pig was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium of the carpal glands consisted of dark and clear cells. The dark cells of these glands exhibited high levels of sialoglycoconjugates, including O -acetylated Sialic Acids, whereas the localization of Sialic Acids linked to α2-3Gal1-4GlcNAc was confined to a subpopulation of the dark cells. Furthermore, all antimicrobial substances and Rab3D were mainly detectable in a subpopulation of the dark cells. The results obtained are discussed with regard to the functional significance of these glands. Our findings suggested that Rab3D is involved in the secretory regulation of sialoglycoconjugates and antimicrobial substances. These secretory products may create a defensive barrier against microbial invasion and play an essential role in the preservation of skin integrity.
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Sialic Acids and antimicrobial substances in the apocrine glands of porcine perianal skin
Archives of Dermatological Research, 2012Co-Authors: Takayuki Nara, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Azuma TsukiseAbstract:The porcine perianal skin shows prominent apocrine glands with large saccular dilatations, whereby the functional significance of the glandular secretions is rather unexplained. Our study focuses on the demonstration of sialoglycoconjugates and antimicrobial substances in these glands, using glycoconjugate histochemical and immunohistochemical methods. The result obtained emphasized the general presence of Sialic Acids, linked to α2-6Gal/GalNAc and α2-3Gaβl1-4GlcNAc, in the secretory cells. The secretory epithelium and luminal secretions also contained a spectrum of antimicrobial substances, such as lysozyme, IgA, lactoferrin, and the peptide group of β-defensins. Realizing that Sialic Acids possess diverging functional properties through various saccharide residues, and that antimicrobial substances serve as a non-specific defense against microorganisms, these secretory products may function as protective agents in order to preserve the integrity of the perianal region. This view includes that the amounts of bacteria on the skin surface are controlled and maintained at the certain level.
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Histochemical localization of Sialic Acids and antimicrobial substances in eccrine glands of porcine snout skin.
European Journal of Histochemistry, 2012Co-Authors: Kousuke Fukui, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Hiroshi Gomi, Hiroshi Sugiya, Azuma TsukiseAbstract:The distribution of Sialic Acids and antimicrobial products (lysozyme, IgA, lactoferrin, β-defensin 2) as well as Rab3D in the eccrine glands of porcine snout skin was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium consisted of two types of secretory cells: dark and clear cells. The dark cells exhibited considerable amounts of sialoglycoconjugates, which included O-acetylated Sialic Acids, whereas Sialic Acids in the sequence Siaα-2-3Gal1-4GlcNAc were confined to some of the dark cells. All antimicrobial substances and Rab3D were demonstrated to be also mainly present in some of the dark cells. Additionally, in the cytological and cytochemical features, the different characteristics were observed among the dark cells. The results obtained are discussed with regard to the functional significance of the eccrine glands. The secretory products elaborated by this gland type may function as protective agents in order to preserve the skin integrity of the snout region, considering that Sialic Acids and antimicrobial substances are important in general defense mechanisms.
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Histochemical properties of Sialic Acids and antimicrobial substances in canine anal glands
European Journal of Histochemistry, 2011Co-Authors: Takayuki Nara, Osamu Fujimori, Tadashi Yasui, Wilfried Meyer, Azuma TsukiseAbstract:The functional properties of Sialic Acids appear to be manifold. Additionally, antimicrobial substances serve as a non-specific defense against microorganisms. In this study, therefore, the localization of Sialic Acids and antimicrobial substances in the anal glands of dog was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium, luminal secretions and excretory ducts exhibited high levels of sialoglycoconjugates that terminated in Siaα2-6Gal/GalNAc or Siaα2-3Gal1-4GlcNAc. Additionally, O-acetylated Sialic Acids were detectable in these glandular structures. Antimicrobial substances, such as lysozyme, immunoglobulin A (IgA), lactoferrin and the peptide group of β-defensins, were also demonstrated as products of the anal glands. The results obtained are discussed with regard to the functional significance of the anal glands. These secretory products may create a defensive barrier against microbial invasion at the anal mucosa.