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Bioactive dressings are usually produced using natural or synthetic polymers. Recently, special attention has been paid to β-glucans that act as immunomodulators and have pro-healing properties. The aim of this research was to use β-1,3-glucan (curdlan) as a base for the production of bioactive dressing materials (curdlan/agarose and curdlan/chitosan) that were additionally enriched with vitamin C and/or hydrocortisone to improve healing of chronic and burn wounds. The secondary goal of the study was to compressively evaluate biological properties of the biomaterials. In this work, it was shown that vitamin C/hydrocortisone-enriched biomaterials exhibited faster vitamin C release profile than hydrocortisone. Consecutive release of the drugs is a desired phenomenon since it protects wounds against accumulation of high and toxic concentrations of the bioactive molecules. Moreover, biomaterials showed gradual release of low doses of the hydrocortisone, which is beneficial during management of burn wounds with hypergranulation tissue. Among all tested variants of biomaterials, dressing materials enriched with hydrocortisone and a mixture of vitamin C/hydrocortisone showed the best therapeutic potential since they had the ability to significantly reduce MMP-2 synthesis by macrophages and increase TGF-β1 release by skin cells. Moreover, materials containing hydrocortisone and its blend with vitamin C stimulated type I collagen deposition by fibroblasts and positively affected their migration and proliferation. Results of the experiments clearly showed that the developed biomaterials enriched with bioactive agents may be promising dressings for the management of non-healing chronic and burn wounds.

Chronic immune response to bone implant may lead to delayed healing and its failure. Thus, newly developed biomaterials should be characterized by high biocompatibility. Moreover, it is well known that macrophages play a crucial role in the controlling of biomaterial-induced inflammatory response. Immune cells synthesize also a great amount of signaling molecules that regulate cell differentiation and tissue remodeling. Non-activated macrophages (M0) may be activated (polarized) into two main types of macrophage phenotype: proinflammatory type 1 macrophages (M1) and anti-inflammatory type 2 macrophages (M2). The aim of the present study was to assess the influence of the newly developed chitosan/agarose/nanohydroxyapatite bone scaffold (Polish Patent) on the macrophage polarization and osteogenic differentiation. Obtained results showed that macrophages cultured on the surface of the biomaterial released an elevated level of anti-inflammatory cytokines (interleukin-4, -10, -13, transforming growth factor-beta), which is typical of the M2 phenotype. Moreover, an evaluation of cell morphology confirmed M2 polarization of the macrophages on the surface of the bone scaffold. Importantly, in this study, it was demonstrated that the co-culture of macrophages-seeded biomaterial with bone marrow-derived stem cells (BMDSCs) or human osteoblasts (hFOB 1.19) enhanced their osteogenic ability, confirming the immunomodulatory effect of the macrophages on the osteogenic differentiation process. Thus, it was proved that the developed biomaterial carries a low risk of inflammatory response and induces macrophage polarization into the M2 phenotype with osteopromotive properties, which makes it a promising bone scaffold for regenerative medicine applications.

Fiber optic Raman spectroscopy and Raman microscopy were used to investigate alterations in the aorta wall and the surrounding perivascular adipose tissue (PVAT) in the murine model of atherosclerosis ( Apoe -/- /Ldlr -/- mice). Both abdominal and thoracic parts of the aorta were studied to account for the heterogenic chemical composition of aorta and its localization-dependent response in progression of atherosclerosis. The average Raman spectra obtained for both parts of aorta cross sections revealed that the chemical composition of intima-media layers along aorta remains relatively homogeneous while the lipid content in the adventitia layer markedly increases with decreasing distance to PVAT. Moreover, our results demonstrate that the increase of the lipid to protein ratio in the aorta wall correlates directly with the increased unsaturation level of lipids in PVAT and these changes occur only in the abdominal, but not in thoracic, aorta. In summary, distinct pathophysiological response in the aortic vascular wall could be uncovered by fiber optic Raman spectroscopy based on simple parameters detecting chemical contents of lipids in PVAT.

Ketamine is an N -methyl-d-aspartate receptor antagonist that has gained wide attention as a potent antidepressant. It has also been recently reported to have prophylactic effects in animal models of depression and anxiety. Alterations of neuroplasticity in different brain regions; such as the hippocampus; prefrontal cortex; and amygdala; are a hallmark of stress-related disorders; and such changes may endure beyond the treatment of symptoms. The present study investigated whether a prophylactic injection of ketamine has effects on structural plasticity in the brain in mice that are subjected to chronic unpredictable stress followed by an 8-day recovery period. Ketamine administration (3 mg/kg body weight) 1 h before stress exposure increased the number of resilient animals immediately after the cessation of stress exposure and positively influenced the recovery of susceptible animals to hedonic deficits. At the end of the recovery period; ketamine-treated animals exhibited significant differences in dendritic spine density and dendritic spine morphology in brain regions associated with depression compared with saline-treated animals. These results confirm previous findings of the prophylactic effects of ketamine and provide further evidence of an association between the antidepressant-like effect of ketamine and alterations of structural plasticity in the brain.