Remodelling of collagen fibers has been described during every phase of cancer genesis and progression. Changes in morphology and organization of collagen fibers contribute to the formation of microenvironment that favors cancer progression and development of metastasis. However, there are only few data about remodelling of collagen fibers in healthy looking mucosa distant from the cancer. Using SHG imaging, electron microscopy and specialized softwares (CT-FIRE, CurveAlign and FiberFit), we objectively visualized and quantified changes in morphology and organization of collagen fibers and investigated possible causes of collagen remodelling (change in syntheses, degradation and collagen cross-linking) in the colon mucosa 10 cm and 20 cm away from the cancer in comparison with healthy mucosa. We showed that in the lamina propria this far from the colon cancer, there were changes in collagen architecture (width, straightness, alignment of collagen fibers and collagen molecules inside fibers), increased representation of myofibroblasts and increase expression of collagen-remodelling enzymes (LOX and MMP2). Thus, the changes in organization of collagen fibers, which were already described in the cancer microenvironment, also exist in the mucosa far from the cancer, but smaller in magnitude.
6 April 2023 in Oxidative Medicine and Cellular Longevity
Pathogenesis of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) remains unclear since it represents an interplay between immunological, endocrine, and neuropsychiatric factors. Patients suffering from CP/CPPS often develop mental health-related disorders such as anxiety, depression, or cognitive impairment. The aim of this study was to investigate depression-like behavior, learning, and memory processes in a rat model of CP/CPPS and to determine the alterations in hippocampal structure and function. Adult male Wistar albino rats ( in each group) from CP/CPPS (single intraprostatic injection of 3% λ-carrageenan, day 0) and Sham (0.9% NaCl) groups were subjected to pain threshold test (days 2, 3, and 7), depression-like behavior, and learning-memory tests (both on day 7). Decreased pain threshold in the scrotal region and histopathological presence of necrosis and inflammatory infiltrate in prostatic tissue confirmed the development of CP/CPPS. The forced swimming test revealed the depression-like behavior evident through increased floating time, while the modified elevated plus maze test revealed learning and memory impairment through prolonged transfer latency in the CP/CPPS group in comparison with Sham ( and , respectively). Biochemical analysis showed decreased serum levels of testosterone in CP/CPPS group vs. the Sham ( ). The CP/CPPS induced a significant upregulation of ICAM-1 in rat cortex ( ) and thalamus ( ) and increased GFAP expression in the hippocampal astrocytes ( ) vs. Sham, suggesting subsequent neuroinflammation and astrocytosis. Moreover, a significantly decreased number of DCX+ and Ki67+ neurons in the hippocampus was observed in the CP/CPPS group ( ) vs. Sham, indicating decreased neurogenesis and neuronal proliferation. Taken together, our data indicates that CP/CPPS induces depression-like behavior and cognitive declines that are at least partly mediated by neuroinflammation and decreased neurogenesis accompanied by astrocyte activation.
Experimental autoimmune encephalomyelitis (EAE) induced in inbred rodents, i.e., genetically identical animals kept under identical environmental conditions, shows variable clinical outcomes. We investigated such variations of EAE in Dark Agouti rats immunized with spinal cord homogenate and identified four groups: lethal, severe, moderate, and mild, at day 28 post immunization. Higher numbers of CD4+ T cells, helper T cells type 1 (Th1) and 17 (Th17) in particular, were detected in the spinal cord of the severe group in comparison with the moderate group. In addition, increased proportion of Th1 and Th17 cells, and heightened levels of interferon (IFN)-γ and interleukin (IL)-6 were detected in the small intestine lamina propria of the severe group. A selective agonist of free fatty acid receptor type 2 (Ffar2) applied orally in the inductive phase of EAE shifted the distribution of the disease outcomes towards milder forms. This effect was paralleled with potentiation of intestinal innate lymphoid cells type 3 (ILC3) regulatory properties, and diminished Th1 and Th17 cell response in the lymph nodes draining the site of immunization. Our results suggest that different clinical outcomes in DA rats are under determinative influence of intestinal ILC3 activity during the inductive phase of EAE.
Ethyl pyruvate (EP) has profound anti-inflammatory and immunomodulatory properties. Here, its effects were determined on experimental autoimmune myocarditis (EAM) induced in mice by heart-specific myosin-alpha heavy chain peptide immunization. EP was applied intraperitoneally, daily, starting with the immunization. Severity of EAM was determined by histological assessment of immune cell infiltrates into the heart. Cells were phenotypically characterized by flow cytometry. Concentration of cytokines in cell culture supernatants and sera was determined by ELISA. EP reduced the infiltration of immune cells into the heart and lessened heart inflammation. Smaller number of total immune cells, as well as of CD11b+ and CD11c+ cells were isolated from the hearts of EP-treated mice. A reduced number of antigen-presenting cells, detected by anti-CD11c, MHC class II and CD86 antibodies, as well as of T helper (Th)1 and Th17 cells, detected by anti-CD4, IFN-γ and IL-17 antibodies, was determined in mediastinal lymph nodes draining the heart, in parallel. In the spleen, only the number of CD11c+ cells were reduced, but not of the other examined populations, thus implying limited systemic effect of EP. Reduced production of IFN-γ and IL-17 by myosin-alpha heavy chain peptide-restimulated cells of the lymph nodes draining the site of immunization was observed in EP-treated mice. Our results clearly imply that EP restrains autoimmunity in EAM. Therapeutic application of EP in the treatment of myocarditis in humans should be addressed in the forthcoming studies.
The morphological method—based on the topology and singularity theory and originally developed for the analysis of the scattering experiments—was extended to be applicable for the analysis of biological data. The usefulness of the topological viewpoint was demonstrated by quantification of the changes in collagen fiber straightness in the human colon mucosa (healthy mucosa, colorectal cancer, and uninvolved mucosa far from cancer). This has been done by modeling the distribution of collagen segment angles by the polymorphic beta-distribution. Its shapes were classified according to the number and type of critical points. We found that biologically relevant shapes could be classified as shapes without any preferable orientation (i.e. shapes without local extrema), transitional forms (i.e. forms with one broad local maximum), and highly oriented forms (i.e. forms with two minima at both ends and one very narrow maximum between them). Thus, changes in the fiber organization were linked to the metamorphoses of the beta-distribution forms. The obtained classification was used to define a new, shape-aware/based, measure of the collagen straightness, which revealed a slight and moderate increase of the straightness in mucosa samples taken 20 and 10 cm away from the tumor. The largest increase of collagen straightness was found in samples of cancer tissue. Samples of healthy individuals have a uniform distribution of beta-distribution forms. We found that this distribution has the maximal information entropy. At 20 cm and 10 cm away from cancer, the transition forms redistribute into unoriented and highly oriented forms. Closer to cancer the number of unoriented forms decreases rapidly leaving only highly oriented forms present in the samples of the cancer tissue, whose distribution has minimal information entropy. The polarization of the distribution was followed by a significant increase in the number of quasi-symmetrical forms in samples 20 cm away from cancer which decreases closer to cancer. This work shows that the evolution of the distribution of the beta-distribution forms—an abstract construction of the mind—follows the familiar laws of statistical mechanics. Additionally, the polarization of the beta-distribution forms together with the described change in the number of quasi-symmetrical forms, clearly visible in the parametric space of the beta-distribution and very difficult to notice in the observable space, can be a useful indicator of the early stages in the development of colorectal cancer.
4 July 2023 in Cellular and Molecular Neurobiology