One of the most severe and widespread periodontal diseases is periodontitis, an inflammatory degenerative process which can eventually lead to tooth loss as the periodontal tissue undergoes morphological changes and can be permanently damaged.
While it is known that this inflammatory process is mainly triggered by bacterial biofilms, the underlying molecular mechanisms are intensively being researched to further improve the understanding of the disease.
Such research frequently involves the analysis of periodontal tissue samples from two points of view:
Analysis of tissue histomorphometry
Analysis of expression profiles of protein markers of interest after respective staining
Thereby, to obtain representative and meaningful results, it is of utmost importance to not just consider and analyze single subregions of the tissue sections, but to take the whole tissue section at the required resolution into account. An excellent solution for the quick, easy and affordable digitization of the small periodontal tissues is the Microvisioneer manual scanning software that allows the creation of zoomable high-quality panoramic images at any resolution with the existing microscope.
Study investigating a potential correlation of syndecans and of enzymes associated with heparan sulfate biosynthesis and modification and periodontitis
In this context, a scientific study in which the expression of syndecans and its biosynthetic enzymes in healthy and diseased periodontal tissue was investigated has been published by a research group around first author Roko Duplancic and Assistant Professor Dr. Darko Kero from the University of Split in Croatia in 2019.
Chemically, syndecans (Sdcs) are heparan sulfate proteoglycans, i.e. molecules consisting of a core protein to which several heparan sulfate (HS) glycosaminoglycan side chains are attached. Four sub-types of syndecans (Sdc 1-4) have been identified in different human tissues. Their functions have been described to be diverse and tissue-dependent; among others, a role of syndecans in the regulation of inflammatory responses has been described. The function of an Sdc is determined by its ultimate chemical structure, and this structure in turn is determined by various enzymes which are active during biosynthesis of the Sdc or which modify the Sdcs post-translational. In particular variations of the chain length and of sulfations in the HS glycosaminoglycan chains are thereby impacting the biochemical features and function of the Sdcs.
Therefore, in the study the expression patterns of Sdcs 1, 2, and 4, as well as of three groups of enzymes responsible for biosynthesis and post-translational modification of HS were analyzed in healthy and diseased periodontal tissue sections from 20 patients per group. The enzymes of interest were exostosins 1 and 2 (EXT1, 2), sulfotransferases 1 and 2 (NDST1, 2) and heparanase 1 (HPSE1). The analyses were performed based on specific staining and subsequent analysis of the respective panoramic brightfield and fluorescence images. Thereby, high resolution brightfield whole slide images were acquired with the Microvisioneer manualWSI scan software.
Below, representative panoramic images of gingiva tissues are shown as examples.
Panoramic images of a gingiva sample from the periodontitis group. (A) Panoramic H/E image acquired at 20X magnification, (B) Panoramic alcian blue image acquired at 10X magnification.
Images provided by courtesy of Dr. Darko Kero.
An initial histomorphometric analysis revealed no significant differences between tissues from healthy and periodontitis patients as the fractions of the epithelial and the stromal compartment did not differ between the groups.
Further, for Sdc1 as well as for the enzymes HPSE1, EXT1, and NDST1, significantly different expression profiles could be observed in healthy and diseased periodontal tissue.
Finally, correlations of expression profiles with inflammatory infiltration were assessed. The expression of Sdcs correlated differentially with the infiltration of inflammatory cells in the healthy control group and the periodontitis group, whereas all enzymes showed similar correlation patterns in the two groups.
Overall, the results implied that syndecans and biosynthetic and modifying enzymes associated to the HS-chains of syndecans could be involved in the modulation of inflammatory responses in periodontitis.
Thus, the study adds to the understanding of molecular changes underlying periodontitis, with a better understanding being crucial for the development of further therapeutic options.
Full study for all details and more information:
Roko Duplancic, Marija Roguljic, Ivan Puhar, Nika Vecek, Ruzica Dragun, Katarina Vukojevic, Mirna Saraga-Babic, Darko Kero: Syndecans and Enzymes for Heparan Sulfate Biosynthesis and Modification Differentially Correlate With Presence of Inflammatory Infiltrate in Periodontitis. Frontiers in Physiology, 2019
DOI: 10.3389/fphys.2019.01248 https://doi.org/10.3389/fphys.2019.01248
For further reading:
Ivna Ćavar, Darko Kero: Correlation of the expression of hyaluronan and CD44 with the presence of gingival inflammatory infiltrate in advanced generalized periodontitis. ST-OPEN, 2020