Microorganism-derived biological macromolecules for tissue engineering.

According to literature, certain microorganism productions mediate biological effects. However, their beneficial characteristics remain unclear. Nowadays, scientists concentrate on obtaining natural materials from live creatures as new sources to produce innovative smart biomaterials for increasing tissue reconstruction in tissue engineering and regenerative medicine. The present review aims to introduce microorganism-derived biological macromolecules, such as pullulan, alginate, dextran, curdlan, and hyaluronic acid, and their available sources for tissue engineering. Growing evidence indicates that these materials can be used as biological material in scaffolds to enhance regeneration in damaged tissues and contribute to cosmetic and dermatological applications. These natural-based materials are attractive in pharmaceutical, regenerative medicine, and biomedical applications. This study provides a detailed overview of natural-based biomaterials, their chemical and physical properties, and new directions for future research and therapeutic applications.

Electromagnetic field exposure as a plausible approach to enhance the proliferation and differentiation of mesenchymal stem cells in clinically relevant scenarios.

Mesenchymal stem/stromal cell (MSC)|-based therapy has been regarded as one of the most revolutionary breakthroughs in the history of modern medicine owing to its myriad of immunoregulatory and regenerative properties. With the rapid progress in the fields of osteo- and musculoskeletal therapies, the demand for MSC-based treatment modalities is becoming increasingly prominent. In this endeavor, researchers around the world have devised new and innovative techniques to support the proliferation of MSCs while minimizing the loss of hallmark features of stem cells. One such example is electromagnetic field (EMF) exposure, which is an alternative approach with promising potential. In this review, we present a critical discourse on the efficiency, practicability, and limitations of some of the relevant methods, with insurmountable evidence backing the implementation of EMF as a feasible strategy for the clinically relevant expansion of MSCs.

Investigating the Impact of Collagen-Chitosan Derived from Scomberomorus Guttatus and Shrimp Skin on Second-Degree Burn in Rats Model.

BACKGROUND: The present study focused on burning as one of the main causes of mortality with detrimental economic and social effects in the world. The purpose of this study was to investigate the impact of collagen-chitosan gel extracted from Scomberomorus guttatus and shrimp skin in the treatment of second degree burn healing among rats. MATERIALS & METHOD: To fulfill the purpose of the study, chitosan and collagen were extracted respectively from shrimp and Scomberomorus guttatus skin waste by the acid-based method and were evaluated by using Pico Tag, SDS-PAGE. The burn wound healing efficiency of marine collagen-chitosan gel was examined in vivo using rats. Three different ratios of collagen and chitosan blend (Col-CH, 1:3, 1:1 and 3:1) were prepared to obtain the most effective Col-CH gel for burn wound healing and were compared to the animals treated with silver sulfadiazine ointment. Healing burn wound was studied by measuring wound surface area with Image J and histopathologic examination was carried out based on the mean of epithelialization, fibroblastic cells, acute and chronic inflammatory cells, angiogenesis, structure collagen and the amount of collagen on days 15 and 25 post-burn. RESULTS: The results of SDS-PAGE indicated that the extracted collagen was type I and it was composed of two α (α1 and α2) chains. Amino acid analysis showed a much higher glaycin content in extracted collagen which amounted to one-third of the total amino. The wound surface measurement showed a significant reduction in wound size in the group treated with Col-CH (3:1) compared to silver-sulfadiazine treated group on 15th and 25th days. Histopathological findings represented a high score in epithelialization, collagen, collagen structure, fibroblast cell and a decrease in inflammatory cells infiltration in Col-CH (3:1) treated group on 25th day. The most obvious finding of the present study is that chitosan-collagen gel (3:1) represented a better efficacy compared to sulfadiazine in burn wound healing on day 25 post-burn.

Human mesenchymal stem cells inhibit the differentiation and effector functions of monocytes.

Although monocytes represent an essential part of the host defence system, their accumulation and prolonged stimulation could be detrimental and may aggravate chronic inflammatory diseases. The present study has explored the less-understood immunomodulatory effects of mesenchymal stem cells on monocyte functions. Isolated purified human monocytes were co-cultured with human umbilical cord-derived mesenchymal stem cells under appropriate culture conditions to assess monocytes' vital functions. Based on the surface marker analysis, mesenchymal stem cells halted monocyte differentiation into dendritic cells and macrophages and reduced their phagocytosis functions, which rendered an inability to stimulate T-cell proliferation. The present study confers that mesenchymal stem cells exerted potent immunosuppressive activity on monocyte functions such as differentiation, phagocytosis and Ag presentation; hence, they promise a potential therapeutic role in down-regulating the unwanted monocyte-mediated immune responses in the context of chronic inflammatory diseases.

Human Mesenchymal Stem Cells-mediated Transcriptomic Regulation of Leukemic Cells in Delivering Anti-tumorigenic Effects.

Treatment of leukemia has become much difficult because of resistance to the existing anticancer therapies. This has thus expedited the search for alternativ therapies, and one of these is the exploitation of mesenchymal stem cells (MSCs) towards control of tumor cells. The present study investigated the effect of human umbilical cord-derived MSCs (UC-MSCs) on the proliferation of leukemic cells and gauged the transcriptomic modulation and the signaling pathways potentially affected by UC-MSCs. The inhibition of growth of leukemic tumor cell lines was assessed by proliferation assays, apoptosis and cell cycle analysis. BV173 and HL-60 cells were further analyzed using microarray gene expression profiling. The microarray results were validated by RT-qPCR and western blot assay for the corresponding expression of genes and proteins. The UC-MSCs attenuated leukemic cell viability and proliferation in a dose-dependent manner without inducing apoptosis. Cell cycle analysis revealed that the growth of tumor cells was arrested at the G0/G1 phase. The microarray results identified that HL-60 and BV173 share 35 differentially expressed genes (DEGs) (same expression direction) in the presence of UC-MSCs. In silico analysis of these selected DEGs indicated a significant influence in the cell cycle and cell cycle-related biological processes and signaling pathways. Among these, the expression of DBF4, MDM2, CCNE2, CDK6, CDKN1A, and CDKN2A was implicated in six different signaling pathways that play a pivotal role in the anti-tumorigenic activity exerted by UC-MSCs. The UC-MSCs perturbate the cell cycle process of leukemic cells via dysregulation of tumor suppressor and oncogene expression.

Evaluation of metabolic and immunological changes in streptozotocin-nicotinamide induced diabetic rats.

Type 2 diabetes is a chronic disease with growing public health concern globally. Finding remedies to assist this health issue requires recruiting appropriate animal model for experimental studies. This study was designated to evaluate metabolic and immunologic changes in streptozotocin-nicotinamide induced diabetic rats as a model of type 2 diabetes. Male rats were induced diabetes using nicotinamide (110 mg/kg) and streptozotocin (65 mg/kg). Following 42 days, biochemical and immunological tests showed that diabetic rats had higher levels of blood glucose, WBC, certain abnormalities in lipid profile and insufficient mitogenic responses of lymphocytes (p<0.05). However, the status of the total antioxidant, inflammatory biomarkers and other parameters of full blood count (except HCT) were not significantly altered. Phenotyping assay indicated insignificant lymphocyte subtype imbalances excluding a significant rise in the level of CD4+CD25+ marker (p<0.05). This model of diabetic animals may represent some but not all symptoms of human type 2 diabetes.