Gizem Baysan

Aims: The local and systemic effects of an elderberry-enriched carboxymethyl chitosan (CMCht-E) gel formulation were evaluated in an experimental rat gingival defect model.Methods: Twenty-one male Wistar rats were randomly assigned to three experimental groups, including a sham group, a CMCht gel group, and a CMCht-E gel group, with seven animals in each group. Standardized gingival defects measuring 3 mm in diameter were surgically created in the mandibular incisor region. Sham defects were irrigated with normal saline only, whereas experimental defects were treated with CMCht or CMCht-E gel. Local tissue responses were evaluated by macroscopic and histological analyses, and systemic effects were assessed using hematological and serum biochemical parameters. Results: Histological analysis revealed a significant intergroup difference in epithelial thickness (p0.05). Hematological and biochemical parameters showed no significant intergroup differences (p>0.05). Conclusion: The elderberry-enriched CMCht gel showed favorable histological healing without inflammatory infiltration or systemic adverse effects, supporting its potential as a locally well-tolerated topical biomaterial with anti-inflammatory properties for gingival wound applications.

The interaction between biomaterials and biological fluids plays a critical role in determining the swelling behavior, biodegradation profile, and integration capacity of scaffolds used in periodontal and peri-implant tissue engineering. This study aimed to analyze the pore structure and weight changes of an elderberry (Sambucus nigra) extract-enriched carboxymethyl chitosan (CMCht-E) biomaterial following exposure to various biological fluids, including normal saline, serum, heparinized blood, and saliva. CMCht-E biomaterial discs were incubated for 24 and 72 hours in normal saline, rat serum, heparinized blood, and saliva. Fluid–biomaterial interactions were evaluated based on microscopic pore diameter measurements and changes in sample weight. Data were statistically analyzed using one-way ANOVA and paired t-tests (p0.05). At 72 hours, the greatest weight gain was observed in the saliva group, whereas the largest pore diameter was recorded in the blood group (p<0.001). Changes in pore diameter were minimal in the normal saline group. Microscopic analyses revealed pore coalescence and enlargement, particularly in blood and saliva environments. The CMCht-E biomaterial exhibited structure- and volume-responsive behavior depending on the characteristics of the biological fluid it interacted with. These findings support its potential for functional optimization based on the target application, reinforcing its clinical relevance in terms of controlled degradation, cellular infiltration, and tissue integration.

Advancements in new treatment methods are becoming increasingly necessary due to a longer life expectancy, particularly in the field of osteochondral tissue engineering. In the present study, osteochondral tissue scaffolds with/without the addition of hawthorn or elderberry extracts were fabricated. Poly(ethylene glycol) diglycidyl ether (PEGDE) cross‐linked carboxymethyl chitosan hydrogel scaffold matrix was used as a control group. The addition of the plant extracts resulted in open porous structures with pore sizes around 100–450 μm and elastic modulus between 0.5 and 0.7 MPa, biomimicking the osteochondral tissue. Scaffolds containing either plant extract showed a high swelling tendency (1500–1750%) and a delayed release of the extracts after a week. Furthermore, the weight loss of the scaffolds after an enzymatic degradation for 56 days was ~30%. In addition, in vitro biocompatibility analyses were performed using bone marrow‐derived mesenchymal stem cells confirming non‐cytotoxicity for all the scaffold types. Biochemical assessment of alkaline phosphatase activity and glycosaminoglycan content yielded results consistent with osteochondral scaffold requirements. Finally, immunohistochemical analyses indicated that the plant extract addition, especially elderberry, increased collagen type I and type II formation. As a result, the addition of both hawthorn and elderberry extracts is a promising approach to osteochondral tissue regeneration.

The main goal of the study was to produce chitosan-collagen hydrogel composite scaffolds consisting of 3D printed poly(lactic acid) (PLA) strut and nanofibrous cellulose for meniscus cartilage tissue engineering. For this purpose, first PLA strut containing microchannels was incorporated into cellulose nanofibers and then they were embedded into chitosan-collagen matrix to obtain micro- and nano-sized topographical features for better cellular activities as well as mechanical properties. All the hydrogel composite scaffolds produced by using three different concentrations of genipin (0.1, 0.3, and 0.5%) had an interconnected microporous structure with a swelling ratio of about 400% and water content values between 77 and 83% which is similar to native cartilage extracellular matrix. The compressive strength of all the hydrogel composite scaffolds was found to be similar (∼32 kPa) and suitable for cartilage tissue engineering applications. Besides, the hydrogel composite scaffold comprising 0.3% (w/v) genipin had the highest tan δ value (0.044) at a frequency of 1 Hz which is around the walking frequency of a person. According to the in vitro analysis, this hydrogel composite scaffold did not show any cytotoxic effect on the rabbit mesenchymal stem cells and enabled cells to attach, proliferate and also migrate through the inner area of the scaffold. In conclusion, the produced hydrogel composite scaffold holds great promise for meniscus tissue engineering.