Suppression of SOCS3 expression in macrophage cells: Potential application in diabetic wound healing

Impaired polarization of M1 to M2 macrophages has been reported in diabetic wounds. We aimed to improve this polarization by down-regulation of expression of the "Suppressor of Cytokine Signaling 3" (SOCS3) gene in macrophages. Two oligodeoxynucleotide (ASO) sequences were designed against SOC3 mRNA and were loaded to mannosylated-polyethyleneimine (Man-PEI). The optimum N/P ratio for Man-PEI-ASO was determined to be 8 based on loading efficiency, particle size, zeta potential, cellular uptake and cytotoxicity assay. pH stability of ASO in Man-PEI-ASO and its protection from DNase I was confirmed. After in vitro treatment of macrophages with Man-PEI-ASO, SOCS3 was downregulated, SOCS1 upregulated, and SOCS1/SOCS3 ratio increased. Also, expressions of macrophage markers of M2 (IL-10, Arg1, CD206) increased and those of M1 (IL-1β, NOS2, CD68) decreased, and secretion of pro-inflammatory cytokines (TNF-α and IL-1β) decreased while that of anti-inflammatory cytokine IL-4 increased. All suggested a polarization into M2 phenotype. Finally, the Man-PEI-ASO was loaded in hydrogel and applied to a diabetic wound model in mice. It improved the healing to the level observed in non-diabetic wounds. We show that using antisense sequences against SOC3 mRNA, macrophage polarization could be directed into the M2 phenotype and healing of diabetic wound could be highly improved.

Synthesis and characterization of a silk fibroin/placenta matrix hydrogel for breast reconstruction

Reconstructive surgery is a complex and demanding interdisciplinary field. One of the major challenges is the production of sizeable, implantable, inexpensive bioprostheses such as breast implants. In this study, porous hybrid hydrogels were fabricated by a combinatorial method using decellularized human placenta (dHplacenta) and silk fibroin. Histology was used to confirm the acellularity of the dHplacenta. The physio-chemical properties of the hydrogels were evaluated using SEM, FTIR, and rheological assays. The synthesized hydrogels exhibited a uniform 3-D microstructure with an interconnected porous network, and the hybrid hydrogels with a 30/70 ratio had improved mechanical properties compared to the other hydrogels. Hybrid hydrogels were also cultured with adipose-derived mesenchymal stem cells (ADSCs). Liposuction was used to obtain adipose tissue from patients, which was then characterized using flow cytometry and karyotyping. The results showed that CD34 and CD31 were downregulated, whereas CD105 and CD90 were upregulated in ADSCs, indicating a phenotype resembling to that of mesenchymal stem cells from the human bone marrow. Moreover, after re-cellularized hydrogel, the live/dead assay and SEM analysis confirmed that most viability and cellular expansion on the hydrogels contained higher ratios of dHplacenta (30/70) than the other two groups. All these findings recapitulated that the 30/70 dHplacenta/silk fibroin hydrogel can perform as an excellent substrate for breast tissue engineering applications.

Regenerative medicine improve neurodegenerative diseases

Regenerative medicine is a subdivision of medicine that improves methods to regrow, repair or replace unhealthy cells and tissues to return to normal function. Cell therapy, gene therapy, nanomedicine as choices used to cure neurodegenerative disease. Recently, studies related to the treatment of neurodegenerative disorders have been focused on stem cell therapy and Nano-drugs beyond other than regenerative medicine. Hence, by data from experimental models and clinical trials, we review the impact of stem cell therapy, gene therapy, and nanomedicine on the treatment of Alzheimer's disease (AD), Parkinson's disease (PD), and Amyotrophic lateral sclerosis (ALS). Indeed, improved knowledge and continued research on gene therapy and nanomedicine in treating Alzheimer's disease, Parkinson's disease, and Amyotrophic lateral sclerosis lead to advancements in effective and practical treatments for neurodegenerative diseases.

Circulatory long noncoding RNAs (circulatory-LNC-RNAs) as novel biomarkers and therapeutic targets in cardiovascular diseases: Implications for cardiovascular diseases complications

Cardiovascular diseases (CVDs) are a group of disorders with major global health consequences. The prevalence of CVDs continues to grow due to population-aging and lifestyle modifications. Non-coding RNAs (ncRNAs) as key regulators of cell signaling pathways have gained attention in the occurrence and development of CVDs. Exosomal-lncRNAs (exos-lncRNAs) are emerging biomarkers due to their high sensitivity and specificity, stability, accuracy and accessibility in the biological fluids. Recently, circulatory and exos-based-lncRNAs are emerging and novel bio-tools in various pathogenic conditions. It is worth mentioning that dysregulation of these molecules has been found in different types of CVDs. In this regard, we aimed to discuss the knowledge gaps and suggest research priorities regarding circulatory and exos-lncRNAs as novel bio-tools and therapeutic targets for CVDs.

Coculture of adipose-derived mesenchymal stem cells/macrophages on decellularized placental sponge promotes differentiation into the osteogenic lineage

BACKGROUND

Several factors like three-dimensional microstructure, growth factors, cytokines, cell-cell communication, and coculture with functional cells can affect the stem cells behavior and differentiation. The purpose of this study was to investigate the potential of decellularized placental sponge as adipose-derived mesenchymal stem cells (AD-MSCs) and macrophage coculture systems, and guiding the osteogenic differentiation of stem cells.

METHODS

The decellularized placental sponge (DPS) was fabricated, and its mechanical characteristics were evaluated using degradation assay, swelling rate, and pore size determination. Its structure was also investigated using hematoxylin and eosin staining and scanning electron microscopy. Mouse peritoneal macrophages and AD-MSCs were isolated and characterized. The differentiation potential of AD-MSCs co-cultured with macrophages was evaluated by RT-qPCR of osteogenic genes on the surface of DPS. The in vivo biocompatibility of DPS was determined by subcutaneous implantation of scaffold and histological evaluations of the implanted site.

RESULTS

The DPS had 67% porosity with an average pore size of 238 μm. The in vitro degradation assay showed around 25% weight loss during 30 days in PBS. The swelling rate was around 50% during 72 h. The coculture of AD-MSCs/macrophages on the DPS showed a significant upregulation of four differentiation osteogenic lineage genes in AD-MSCs on days 14 and 21 and a significantly higher mineralization rate than the groups without DPS. Subcutaneous implantation of DPS showed in vivo biocompatibility of scaffold during 28 days follow-up.

CONCLUSIONS

Our findings suggest the decellularized placental sponge as an excellent bone substitute providing a naturally derived matrix substrate with biostructure close to the natural bone that guided differentiation of stem cells toward bone cells and a promising coculture substrate for crosstalk of macrophage and mesenchymal stem cells in vitro.

In-situ forming hydrogel based on thiolated chitosan/carboxymethyl cellulose (CMC) containing borate bioactive glass for wound healing

Suitable wound dressings for accelerating wound healing are actively being designed and synthesised. In this study, thiolated chitosan (tCh)/oxidized carboxymethyl cellulose (OCMC) hydrogel containing Cu-doped borate bioglass (BG) was developed as a wound dressing to improve wound healing in a full-thickness skin defect of mouse animal model. Thiolation was used to incorporate thiol groups into chitosan (Ch) to enhance its water solubility and mucoadhesion characteristics. Here, the in situ forming hydrogel was successfully developed using the Schiff-based reaction, and its physio-chemical and antibacterial characteristics were examined. Borate BG was also incorporated in the generated hydrogel to promote angiogenesis and tissue regeneration at the wound site. Investigations of in vitro cytotoxicity assays demonstrated that the synthesised hydrogels showed good biocompatibility and promoted cell growth. These results inspired us to investigate the effectiveness of skin wound healing in a mouse model. On the backs of animals, two full-thickness wounds were created and treated utilising two different treatment conditions: (1) OCMC/tCh hydrogel, (2) OCMC/tCh/borate BG, and (3) control defect. The wound closure ratio, collagen deposition, and angiogenesis activity were measured after 14 days to determine the healing efficacy of the in situ hydrogels used as wound dressings. Overall, the hydrogel containing borate BG was maintained in the defect site, healing efficiency was replicable, and wound healing was apparent. In conclusion, we found consistent angiogenesis, remodelling, and accelerated wound healing, which we propose may have beneficial effects on the repair of skin defects.

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.

Stem Cell-Mediated Angiogenesis in Skin Tissue Engineering and Wound Healing

The timely management of skin wounds has been an unmet clinical need for centuries. While there have been several attempts to accelerate wound healing and reduce the cost of hospitalisation and the healthcare burden, there remains a lack of efficient and effective wound healing approaches. In this regard, stem cell‐based therapies have garnered an outstanding position for the treatment of both acute and chronic skin wounds. Stem cells of different origins (e.g., embryo‐derived stem cells) have been utilised for managing cutaneous lesions; specifically, mesenchymal stem cells (MSCs) isolated from foetal (umbilical cord) and adult (bone marrow) tissues paved the way to more satisfactory outcomes. Since angiogenesis plays a critical role in all four stages of normal wound healing, recent therapeutic approaches have focused on utilising stem cells for inducing neovascularisation. In fact, stem cells can promote angiogenesis via either differentiation into endothelial lineages or secreting pro‐angiogenic exosomes. Furthermore, particular conditions (e.g., hypoxic environments) can be applied in order to boost the pro‐angiogenic capability of stem cells before transplantation. For tissue engineering and regenerative medicine applications, stem cells can be combined with specific types of pro‐angiogenic biocompatible materials (e.g., bioactive glasses) to enhance the neovascularisation process and subsequently accelerate wound healing. As such, this review article summarises such efforts emphasising the bright future that is conceivable when using pro‐angiogenic stem cells for treating acute and chronic skin wounds.

Stem cell therapy for COVID-19 pneumonia

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus is a highly contagious microorganism, and despite substantial investigation, no progress has been achieved in treating post-COVID complications. However, the virus has made various mutations and has spread around the world. Researchers have tried different treatments to reduce the side effects of the COVID-19 symptoms. One of the most common and effective treatments now used is steroid therapy to reduce the complications of this disease. Long-term steroid therapy for chronic inflammation following COVID-19 is harmful and increases the risk of secondary infection, and effective treatment remains challenging owing to fibrosis and severe inflammation and infection. Sometimes our immune system can severely damage ourselves in disease. In the past, many researchers have conducted various studies on the immunomodulatory properties of stem cells. This property of stem cells led them to modulate the immune system of autoimmune diseases like diabetes, multiple sclerosis, and Parkinson's. Because of their immunomodulatory properties, stem cell-based therapy employing mesenchymal or hematopoietic stem cells may be a viable alternative treatment option in some patients. By priming the immune system and providing cytokines, chemokines, and growth factors, stem cells can be employed to build a long-term regenerative and protective response. This review addresses the latest trends and rapid progress in stem cell treatment for Acute Respiratory Distress Syndrome (ARDS) following COVID-19.

Transplantation of decellularised human amniotic membranes seeded with mesenchymal stem cell-educated macrophages into animal models

The reconstruction of chronic skin wounds remains a public health challenge in dermatology. Precisely controlling and monitoring the wound-healing process should result in enhanced outcomes for the patient. Cell-based therapies have shown great potential in medicine due to their immunomodulatory and healing properties. Herein, we produced activated macrophages by treating circulating monocytes with mesenchymal stem cell (MSC) supernatant. We also demonstrated the critical role of activated macrophages transplantation using amniotic membranes in accelerating wound healing in an animal wound model. The activated macrophages not only exhibited immunomodulatory cytokines like transforming growth factorβ (TGFβ) and interleukin 10 (and IL10) secretion but also showed attachment and proliferation ability on the amniotic membrane scaffold. Moreover, MSCs supernatant-treated cells also displayed significant ARG1, CD206, and IL 10 genes expression. Inspired by the in vitro results, we examined the in vivo therapeutic efficacy of the activated macrophage transplantation using an acellular amniotic membrane carrier in a full-thickness cutaneous wound model. The wound healing rate was significant in the group treated with macrophages generated via mesenchymal cell therapy seeded human amniotic membrane. There was less scarring in the wound sites after placing cell-scaffold constructs in the wound sites in the animal models. Overall, macrophages stimulated with mesenchymal cells' supernatant exhibited improved healing processes in incisional wounds by decreasing the inflammatory phase, increasing angiogenesis, and reducing scar tissue development.

Osteogenic Potential of Magnesium (Mg)-Doped Multicomponent Bioactive Glass: In Vitro and In Vivo Animal Studies

The use of bioactive glasses (BGs) has been quite fruitful in hard tissue engineering due to the capability of these materials to bond to living bone. In this work, a melt-derived magnesium (Mg)-doped BG (composition: 45SiO₂–3P₂O₅–26CaO–15Na₂O–7MgO–4K₂O (mol.%)) was synthesized for being used in bone reconstruction. The prepared BGs were then manufactured as three-dimensional (3D) scaffolds by using the sponge replica approach. The microstructure of the samples was assessed by X-ray diffraction (XRD) and the surface morphology was observed by using scanning electron microscopy (SEM). The in vitro bioactivity and the release of osteo-stimulatory Mg²⁺ ions from the prepared samples were investigated over 7 days of incubation in simulated body fluids (SBF). In vitro cellular analyses revealed the compatibility of the Mg-doped BGs with human osteosarcoma cells (MG-63 cell line). Moreover, the Mg-doped BGs could induce bone nodule formation in vitro and improve the migratory ability of human umbilical vein endothelial cells (HUVECs). In vivo osteogenic capacity was further evaluated by implanting the BG-derived scaffolds into surgically-created critical-size bone defects in rats. Histological and immunohistological observations revealed an appropriate bone regeneration in the animals receiving the glass-based scaffolds after 12 weeks of surgery. In conclusion, our study indicates the effectiveness of the Mg-doped BGs in stimulating osteogenesis in both in vitro and in vivo conditions.

Animal Kernicterus Models: Progress and Challenges

Kernicterus is a leading cause of neonatal death throughout the world, especially in low-middle-income countries. It is developed by an unconjugated hyperbilirubinemia in the blood and brain tissue, triggering pathological processes that spawn neurotoxicity and neurodegeneration. However, the biological mechanism (s) of bilirubin-induced neurotoxicity and Kernicterus development remain to be well elucidated. Likewise, a practical therapeutic approach for human Kernicterus has yet to be found. Undoubtedly, animal models of Kernicterus can be helpful in the identification of underlying biological processes of hyperbilirubinemia evolution to Kernicterus, as well as the evaluation of various treatments efficacy in preclinical studies. More importantly, establishing an animal model that can mimic the Kernicterus and its behavioral, neuro-histological, and hematological manifestations is a severe priority in preclinical studies. So far, several Kernicterus animal models have been established that could partially mimic one or more clinical and paraclinical signs of human Kernicterus. The present study aimed to review all methods modeling Kernicterus with a focus on their potentials and shortcomings and subsequently provide the optimal methods for an ideal Kernicterus animal model.

CRISPR-Associated (CAS) Effectors Delivery via Microfluidic Cell-Deformation Chip

Identifying new and even more precise technologies for modifying and manipulating selectively specific genes has provided a powerful tool for characterizing gene functions in basic research and potential therapeutics for genome regulation. The rapid development of nuclease-based techniques such as CRISPR/Cas systems has revolutionized new genome engineering and medicine possibilities. Additionally, the appropriate delivery procedures regarding CRISPR/Cas systems are critical, and a large number of previous reviews have focused on the CRISPR/Cas9-12 and 13 delivery methods. Still, despite all efforts, the in vivo delivery of the CAS gene systems remains challenging. The transfection of CRISPR components can often be inefficient when applying conventional delivery tools including viral elements and chemical vectors because of the restricted packaging size and incompetency of some cell types. Therefore, physical methods such as microfluidic systems are more applicable for in vitro delivery. This review focuses on the recent advancements of microfluidic systems to deliver CRISPR/Cas systems in clinical and therapy investigations.

Synthesis and Characterization of Exopolysaccharide Encapsulated PCL/Gelatin Skin Substitute for Full-Thickness Wound Regeneration

Loss of skin integrity can lead to serious problems and even death. In this study, for the first time, the effect of exopolysaccharide (EPS) produced by cold-adapted yeast R. mucilaginosa sp. GUMS16 on a full-thickness wound in rats was evaluated. The GUMS16 strain's EPS was precipitated by adding cold ethanol and then lyophilized. Afterward, the EPS with polycaprolactone (PCL) and gelatin was fabricated into nanofibers with two single-needle and double-needle procedures. The rats' full-thickness wounds were treated with nanofibers and Hematoxylin and eosin (H&E) and Masson's Trichrome staining was done for studying the wound healing in rats. Obtained results from SEM, DLS, FTIR, and TGA showed that EPS has a carbohydrate chemical structure with an average diameter of 40 nm. Cell viability assessments showed that the 2% EPS loaded sample exhibits the highest cell activity. Moreover, in vivo implantation of nanofiber webs on the full-thickness wound on rat models displayed a faster healing rate when EPS was loaded into a nanofiber. These results suggest that the produced EPS can be used for skin tissue engineering applications.

Cell Sources in Cardiac Tissue Engineering: Current Choices

The past decade has evidenced numerous developments in the treatment of heart diseases; however many patients with chronic heart failure suffer from low quality of life. Therapeutic methods, including drug-delivery as well as heart transplantation, have been used to improve quality of life. Cell therapy and tissue engineering have been recently introduced to the field of medicine as a novel therapeutic approach. Treatment of heart diseases has seen novel development through the introduction of cell therapy approaches. Based on the evidence, cell therapy has emerged as a promising therapeutic strategy for the treatment of cardiac diseases. Since the first cell transplant to patients, different types of (stem) cells have been studied. This study aims to provide a comprehensive review of different types of cells and their roles in cardiac cell-based therapy.

Design and fabrication of polycaprolactone/gelatin composite scaffolds for diaphragmatic muscle reconstruction

Diaphragmatic wall defects caused by congenital disorders or disease remain a major challenge for physicians worldwide. Polymeric patches have been extensively explored within research laboratories and the clinic for soft tissue and diaphragm reconstruction. However, patch usage may be associated with allergic reaction, infection, granulation, and recurrence of the hernia. In this study, we designed and fabricated a porous scaffold using a combination of 3D printing and freeze-drying techniques. A 3D printed polycaprolactone (PCL) mesh was used to reinforcegelatin scaffolds, representing an advantage over previously reported examples since it provides mechanical strength and flexibility. In vitro studies showed that adherent cells were anchorage-dependent and grew as a monolayer attached to the scaffolds. Microscopic observations indicated better cell attachments for the scaffolds with higher gelatin content as compared with the PCL control samples. Tensile testing demonstrated the mechanical strength of samples was significantly greater than adult diaphragm tissue. The biocompatibility of the specimens was investigated in vivo using a subcutaneous implantation method in Bagg albino adult mice for 20 days, with the results indicating superior cellular behavior and attachment on scaffolds containing gelatin in comparison to pure PCL scaffolds, suggesting that the porous PCL/gelatin scaffolds have potential as biodegradable and flexible constructs for diaphragm reconstruction.

Enhanced healing of a full-thickness wound by a thermoresponsive dressing utilized for simultaneous transfer and protection of adipose-derived mesenchymal stem cells sheet

To boost the healing process in a full-thickness wound, a simple and efficient strategy based on adipose-derived mesenchymal stem cells (ADSCs) transplantation is described in this work. To increase the chance of ADSCs immobilization in the wound bed and prevent its migration, these cells are fully grown on the surface of a thermoresponsive dressing membrane under in vitro condition. Then, the cells sheet with their secreted extracellular matrix (ECM) is transferred to the damaged skin with the help of this dressing membrane. This membrane remains on wound bed and acts both as a cell sheet transfer vehicle, after external reduction of temperature, and protect wound during the healing process like a common wound dressing. The visual inspection of wounded skin (rat animal model) at selected time intervals shows a higher wound closure rate for ADSCs treated group. For this group of rats, the better quality of reconstructed tissue is approved by results of histological and immunohistochemical analysis since the higher length of the new epidermis, the higher thickness of re-epithelialization layer, a higher level of neovascularization and capillary density, and the least collagen deposition are detected in the healed tissue.

Enhanced antimicrobial and full-thickness wound healing efficiency of hydrogels loaded with heparinized ZnO nanoparticles: In vitro and in vivo evaluation

Nanotechnology-based fabricated wound dressings are known as appropriate substrates to enhance healing in both acute and chronic wounds. These types of materials have the ability to deliver therapeutic agents. In this study, a wound dressing including heparinized zinc oxide nanoparticles in combination with chitosan and poly(vinyl alcohol) was developed to investigate its antibacterial and regenerative properties in a rat model of full thickness skin wounds. By adding nanoparticles, the mechanical strength increased up to twice as compared to the sample without nanoparticles. In addition, heparin release profile follows the Hixson-Crowell release kinetic. Protein adsorption enhanced by adding nanoparticles in hydrogels and the prepared wound dressings were completely biocompatible. In terms of antibacterial activity, the minimum inhibitory concentration decreased by conjugation of heparin on the surface of zinc oxide nanoparticles compared to the non-functionalized nanoparticles, and, this shows the increased antibacterial synergistic effect by adding heparin to nanoparticles. Furthermore, it was found that the heparinized zinc oxide nanoparticles effectively accelerate wound closure, re-epithelialization and decrease collagen deposition compared to other groups after implantation. Hence, the prepared wound dressings have the capacity to significantly enhance healing of acute wounds.

Mineralized Human Amniotic Membrane as a Biomimetic Scaffold for Hard Tissue Engineering Applications

The human amniotic membrane (HAM) has been viewed as a potential regenerative material for a wide variety of injured tissues because of its collagen-rich content. High degradability of HAM limits its wide practical application in bone tissue engineering. In this study, the natural matrix of the decellularized amniotic membrane was developed by the double diffusion method. The results confirmed a reduction of the amniotic membrane's degradability because of the deposition of calcium and phosphate ions during the double diffusion process. Real-time PCR results showed a high expression of osteogenesis-related genes from adipose-derived mesenchymal stem cells (ADMSCs) cultured on the surface of the developed mineralized amniotic membrane (MAM). Further in vivo experiments were conducted using an MAM preseeded with ADMSCs and a critical-size rat calvarial defect model. Histopathological results confirmed that the MAM + cell sample has excellent potential in bone regeneration.

Thermo-responsive chitosan hydrogel for healing of full-thickness wounds infected with XDR bacteria isolated from burn patients: In vitro and in vivo animal model

Treatment of non-healing skin wounds infected with extensively drug-resistant (XDR) bacteria remains as a big challenge. To date, different biomaterials have been applied for treatment of post-wound infections, nevertheless their efficacy for treatment of the wounds infected with XDR isolates has not been determined yet. In this study, the potential of the thermo-responsive chitosan (TCTS) hydrogel for protection of full-thickness wounds XDR bacteria isolated from burn patients was evaluated both in vitro and in vivo in a rat model. Antibacterial activity of the TCTS hydrogel against standard strain and clinical isolates of Acinetobacter baumannii, cytobiocompatibility for Hu02 fibroblast cells, degradation rate and swelling ratio were determined in vitro. MTT assay and disk diffusion test indicated no detectable cytotoxicity and antibacterial activity in vitro, respectively. In vivo study showed significant acceleration of wound healing, re-epithelialization, wound closure, and decreased colony count in the TCTS hydrogel group compared with control. This study suggests TCTS hydrogel as an excellent wound dressing for management of the wounds infected with XDR bacteria, and now promises to proceed with clinical investigations.

Copper-enriched diamond-like carbon coatings promote regeneration at the bone-implant interface

There have been several attempts to design innovative biomaterials as surface coatings to enhance the biological performance of biomedical implants. The objective of this study was to design multifunctional Cu/a-C:H thin coating depositing on the Ti-6Al-4V alloy (TC4) via magnetron sputtering in the presence of Ar and CH4 for applications in bone implants. Moreover, the impact of Cu amount and sp2/sp3 ratio on the interior stress, corrosion behavior, mechanical properties, and tribological performance and biocompatibility of the resulting biomaterial was discussed. X-ray photoelectron spectroscopy (XPS) revealed that the sp2/sp3 portion of the coating was enhanced for samples having higher Cu contents. The intensity of the interior stress of the Cu/a-C:H thin bio-films decreased by increase of Cu content as well as the sp2/sp3 ratio. By contrast, the values of Young's modulus, the H3/E2 ratio, and hardness exhibited no significant difference with enhancing Cu content and sp2/sp3 ratio. However, there was an optimum Cu content (36.8 wt.%) and sp2/sp3 ratio (4.7) that it is feasible to get Cu/a-C:H coating with higher hardness and tribological properties. Electrochemical impedance spectroscopy test results depicted significant improvement of Ti-6Al-4V alloy corrosion resistance by deposition of Cu/a-C:H thin coating at an optimum Ar/CH4 ratio. Furthermore, Cu/a-C:H thin coating with higher Cu contents showed better antibacterial properties and higher angiogenesis and osteogenesis activities. The coated samples inhibited the growth of bacteria as compared to the uncoated sample (p < 0.05). In addition, such coating composition can stimulate angiogenesis, osteogenesis and control host response, thereby increasing the success rate of implants. Moreover, Cu/a-C:H thin films encouraged development of blood vessels on the surface of titanium alloy when the density of grown blood vessels was increased with enhancing the Cu amount of the films. It is speculated that such coating can be a promising candidate for enhancing the osseointegration features.

Intrahippocampal Transplantation of Undifferentiated Human Chorionic- Derived Mesenchymal Stem Cells Does Not Improve Learning and Memory in the Rat Model of Sporadic Alzheimer Disease

BACKGROUND AND OBJECTIVE

Alzheimer's Disease (AD) is a progressive neurodegenerative disorder with consequent cognitive impairment and behavioral deficits. AD is characterized by loss of cholinergic neurons and the presence of beta-amyloid protein deposits. Stem cell transplantation seems to be a promising strategy for regeneration of defects in the brain.

METHOD

One of the suitable type of stem cells originated from fetal membrane is Chorion-derived Mesenchymal Stem Cells (C-MSCs). MSCs were isolated from chorion and characterized by Flowcytometric analysis. Then C-MSCs labeled with DiI were transplanted into the STZ induced Alzheimer disease model in rat.

RESULTS

Nissl staining and behavior test were used to assess the efficacy of the transplanted cells. Phenotypic and Flowcytometric studies showed that isolated cells were positive for mesenchymal stem cell marker panel with spindle like morphology.

CONCLUSION

Learning and memory abilities were not improved after stem cell transplantation. C-MSCs transplantation can successfully engraft in injured site but the efficacy and function of transplanted cells were not clinically satisfied.

Decellularization and preservation of human skin: A platform for tissue engineering and reconstructive surgery

A matrix derived from natural tissue functions as a highly biocompatible and versatile scaffold for tissue engineering applications. It can act as a supportive construct that provides a niche for colonization by host cells. In this work, we describe a cost-effective, reliable and reproducible protocol for decellularization and preservation of human skin as a potential soft tissue replacement. The decellularized human skin is achieved using purely chemical agents without any enzymatic steps. The suitability of the proposed method for the preservation of the extracellular matrix (ECM) structure and its main components and integrity were evaluated using histological and immunohistochemical analysis. Cryopreservation and final sterility were conducted using programmable freeze-drying and gamma irradiation. The architecture, basement membrane and 3D structure of ECM can be successfully preserved after decellularization. Our protocol was found to be appropriate to maintain key proteins such as collagen type I, III, IV and laminin in the structure of final scaffold. This protocol offers a novel platform for the preparation of a dermal substitute for potential clinical applications. STATEMENT OF SIGNIFICANCE: Clinical application of naturally-based scaffolds for verity of health problems obliges development of a reproducible and effective technology that does not change structural and compositional material properties during scaffold preparation and preservation. Lack of an effective protocol for the production of biological products using decellularization method is still remaining. This effort is directing to solve this challenge in order to accomplish the off-the -shelf availability of decellularized dermal scaffold in market for clinical application.

Nitric oxide-releasing vascular grafts: A therapeutic strategy to promote angiogenic activity and endothelium regeneration

Small-diameter vascular grafts (SDVGs) are associated with a high incidence of failure due to infection and obstruction. Although several vascular grafts are commercially available, specific anatomical differences of defect sites require patient-based design and fabrication. Design and fabrication of such custom-tailored grafts are possible with 3d-printing technology. The aim of this study is to develop 3d-printed SDVGs with a nitric oxide (NO)-releasing coating to improve the success rate of implantation. The SDVGs were printed from polylactic acid and coated with blending of 10 wt% S-nitroso-N-acetyl-D-penicillamine into the polymeric substrate consisting of poly (ethylene glycol) and polycaprolactone. Our results show that NO is released in the physiological range (0.5-4 × 10^-10 mol·cm^-2·min^-1) for 14 days and NO-releasing coating showed significant antibacterial potential against Gram-positive and Gram-negative strains. It was shown that both NO-releasing and control grafts are biocompatible in-vitro and in-vivo. Interestingly, the NO-releasing SDVGs dramatically enhanced ECs proliferation and significantly enhanced ECs migration in-vitro compared to control grafts. In addition, the NO-releasing SDVGs showed angiogenic potential in-vivo which can further prove the results of our in-vitro study. These findings are expected to facilitate tissue regeneration and integration of custom-made vascular implants with enhanced clinical success. STATEMENT OF SIGNIFICANCE: A series of 3d-printed small-diameter vascular grafts (SDVGs, <6 mm) with controlled release of nitric oxide (NO) were prepared to combine the advantages of 3D printing technology and NO-releasing systems. The resulting NO-releasing grafts were promisingly showing sustained NO release in the physiological range over a two weeks period. In addition to the evaluation of endothelial cell migration in-vitro, we implanted for the first time the NO-releasing vascular grafts in a chick chorioallantoic membrane (CAM) to investigate the effect of the prepared grafts on the angiogenesis in-vivo. The fabricated grafts also exhibited bactericidal properties which prevent the formation of a biofilm layer and can thereby enhance the chance of endothelialization on the surface. Taken together, the innovative combination of rapid and highly accurate 3d-printing technology as a patient-specific fabrication method with NO-releasing coating represents a promising approach to develop bactericidal SDVGs with improved endothelialization.

Olfactory mucosa stem cells: An available candidate for the treatment of the Parkinson's disease

Olfactory ectomesenchymal stem cells (OE-MSCs) possess the immunosuppressive activity and regeneration capacity and hold a lot of promises for neurodegenerative disorders treatment. This study aimed to determine OE-MSCs which are able to augment and differentiate into functional neurons and regenerate the CNS and also examine whether the implantation of OE-MSCs in the pars compacta of the substantia nigra (SNpc) can improve Parkinson's symptoms in a rat model-induced with 6-hydroxydopamine. We isolated OE-MSCs from lamina propria in olfactory mucosa and characterized them using flow cytometry and immunocytochemistry. The therapeutic potential of OE-MSCs was evaluated by the transplantation of isolated cells using a rat model of acute SN injury as a Parkinson's disease. Significant behavioral improvement in Parkinsonian rats was elicited by the OE-MSCs. The results demonstrate that the expression of PAX2, PAX5, PITX3, dopamine transporter, and tyrosine hydroxylase was increased by OE-MSCs compared to the control group which is analyzed with real-time polymerase chain reaction technique and immunohistochemical staining. In the outcome, the transplantation of 1,1'-dioctadecyl-3,3,3'3'-tetramethyl indocarbocyanine perchlorate labeled OE-MSCs that were fully differentiated to dopaminergic neurons contribute to a substantial improvement in patients with Parkinson's. Together, our results provide that using OE-MSCs in neurodegenerative disorders might lead to better neural regeneration.

Smart electrospun nanofibers containing PCL/gelatin/graphene oxide for application in nerve tissue engineering

Currently graphene-doped electrospun scaffolds have been a matter of great interest to be exploited in biomedical fields such as tissue engineering and drug delivery applications. The main objective of this paper is to evaluate the effect of graphene on biological properties of PCL/gelatin nanofibrous mats. SEM analysis was conducted to investigate the morphology of the electrospun nanofibers. The in-vitro cellular proliferation of PC12 cells on nanofibrous web was also investigated. Electrospun PCL/gelatin/graphene nanofibrous mats exhibited 99% antibacterial properties against gram-positive and gram-negative bacteria. Drug release studies indicated that the π-π stacking interaction between TCH and graphene has led to the far better controlled release of TCH from electrospun PCL/gelatin/graphene compared to PCL/gelatin nanofibrous scaffolds. These superior properties along with an improvement in hydrophilicity and biodegradation features has made the nanofibers a promising candidate to be used as electrically conductive scaffolds in neural tissue engineering as well as controlled drug delivery.

Transplantation of Adipose Tissue-Derived Stem Cells into Brain Through Cerebrospinal Fluid in Rat Models: Protocol Development and Initial Outcome Data

Background:

Cell therapy is an important strategy for the treatment of incurable diseases including those that occur in the Central Nervous System (CNS). Among different strategies, the method of delivering or transplantation of cells into the brain has shown significant effects on regeneration. In this study, a new protocol has been developed for the transplantation of adipose tissuederived stem cells into the brain through Cerebrospinal Fluid (CSF) in rat models.

Methods:

For this purpose, a wide range of ages (7-30 days old) of male neonates of Wistar rats was used. Moreover, human adipose tissue was obtained from a superficial layer of abdomen through liposuction surgery. The size of the inserted part of needle to access middle cranial fossa and subarachnoid space in animals with an average weight of 10-80 g was determined. In addition, to confirm the entrance of needle into the subarachnoid space, CSF was aspirated slowly and then injection was done within two minutes.

Results:

The findings showed the presence of transplanted human Adipose-Derived Stem Cells (hADSC) in the cerebellum and basal ganglia following three days and also after two months that confirmed the entrance of transplanted cells into the cerebrospinal fluid and migration of them into the brain tissue. All the animals survived after the transplantation process, with the lowest side effects compared to the available conventional methods.

Conclusion:

It can be concluded that the cells could be efficiently transplanted into CSF through subarachnoid space by injection via superior orbital fissure with a minimally invasive technique.

The Effect of Alpha-Tocopherol on Morphine Tolerance-induced Expression of c-fos Proto-oncogene from a Biotechnological Perspective

BACKGROUND

The increase of oxidant compounds is the most well-known reasons for the tolerance to the analgesic properties of Morphine. Additionally, the production of proxy-nitrite impairs receptors, proteins and enzymes involved in the signaling pathways of analgesia, apoptosis and necrosis. Also, we revised all patents relating to opioid tolerance control methods.

OBJECTIVE

The aim of this study was to assess the effects of Alpha-tocopherol as an anti-oxidant agent to reduce Morphine tolerance.

METHOD

Forty male rats randomly divided into four groups. 10 mg/kg of morphine was injected subcutaneously to create the desired level of tolerance. After modeling, 70 mg/kg Alpha- Tocopherol was injected intraperitoneal. Also, the hot plate recorded pain threshold alterations was used to evaluate the behavioral test. All tissue samples were extracted from the spinal cord, thalamus and frontal cortex for molecular and gene expression evaluations. Also, the effect of Alpha- Tocopherol on the apoptosis and necrosis parameters was analyzed using nissl staining and tunel test.

RESULTS

The time latency results showed that there were no significant differences in the different days in groups treated with Morphine plus Alpha-Tocopherol. However, our data highlighted that the pain threshold and their time latency in respond to it had substantially increased in comparison with the control group. Furthermore, we found that the Alpha-Tocopherol obviously decreased c-fos gene expression, especially in the spinal cord.

CONCLUSION

Thus, co-administration of Alpha-Tocopherol with Morphine can decrease the adverse effects of nitrite proxy, which is released due to repeated injections of Morphine.

Correction to: Transplantation of Human Chorion-Derived Cholinergic Progenitor Cells: a Novel Treatment for Neurological Disorders

The original version of this article unfortunately contained mistake in the affiliation. Affiliation 1 should be read as "Neuroscience Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran". The original article has been corrected.

3D Protein-Based Bilayer Artificial Skin for the Guided Scarless Healing of Third-Degree Burn Wounds in Vivo

Severe burn injuries can lead to delays in healing and devastating scar formation. Attempts have been made to develop a suitable skin substitute for the scarless healing of such skin wounds. Currently, there is no effective strategy for completely scarless healing after the thermal injuries. In our recent work, we fabricated and evaluated a 3D protein-based artificial skin made from decellularized human amniotic membrane (AM) and electrospun nanofibrous silk fibroin (ESF) in vitro. We also characterized both biophysical and cell culture investigation to establish in vitro performance of the developed bilayer scaffolds. In this report, we evaluate the appropriate utility of this fabricated bilayered artificial skin in vivo with particular emphasis on healing and scar formation due to the biochemical and biomechanical complexity of the skin. For this work, AM and AM/ESF membranes alone or seeded with adipose-tissue-derived mesenchymal stem cells (AT-MSCs) are implanted on full-thickness burn wounds in mice. The healing efficacy and scar formation are evaluated at 7, 14, and 28 days post-implantation in vivo. Our data reveal that ESF accelerates the wound-healing process through the early recruitment of inflammatory cells such as macrophages into the defective site as well as the up-regulation of angiogenic factors from the AT-MSCs and the facilitation of the remodeling phase. In vivo application of the prepared AM/ESF membrane seeded with the AT-MSCs reduces significantly the post-burn scars. The in vivo data suggest that the potential applications of the AM/ESF bilayered artificial skin may be considered a clinical translational product with stem cells to guide the scarless healing of severe burn injuries.

Strontium- and cobalt-substituted bioactive glasses seeded with human umbilical cord perivascular cells to promote bone regeneration via enhanced osteogenic and angiogenic activities

Designing and developing new biomaterials to accelerate bone healing are currently under progress. In this study, we attempted to promote osteogenesis using strontium- and cobalt-substituted bioactive glasses (BGs) seeded with human umbilical cord perivascular cells (HUCPVCs) in a critical size defect in the distal femur of rabbit animal model. The BG particles were successfully synthesized in the form of granules using the melt-derived route. After being isolated, HUCPVCs were expanded and then characterized to use during in vitro and in vivo procedures. The in vitro effects of the synthesized glasses on the isolated HUCPVCs as well as on cell lines SaOS-2 (selected for screening the osteogenetic potential) and HUVEC (selected for screening the angiogenic potential) were assessed by analyzing cytotoxicity, cell attachment, bone-like nodule formation, and real time PCR. The results of in vitro tests indicated cytocompatibility of the synthesized BG particles. For in vivo study, the HUCPVCs-seeded BGs were implanted into the animal's body. Radiographic imaging, histology and immunohistology staining were performed on the harvested specimens at 4 and 12weeks post-surgery. The in vivo evaluation of the samples showed that all the cell/glass constructs accelerated bone healing process in comparison with blank controls. The best in vitro and in vivo results were associated to the BGs containing both strontium and cobalt ions. This group of bioactive glasses is able to promote both osteogenesis and angiogenesis and can therefore be highly suitable for the development of advanced functional bone substitutes.

STATEMENT OF SIGNIFICANCE

Bone regeneration is considered as an unmet clinical need. The most recent researches focused on incorporation of strontium (Sr²⁺) and cobalt (Co²⁺) ions into bioactive glasses structure. Strontium is an alkaline earth metal which is currently used in the treatment of osteoporosis. Also, cobalt is considered as another promising element in the bone regeneration field that may induce hypoxia-mediated angiogenesis. In this study, the osteogenic potential of the strontium- and cobalt-substituted bioactive glasses in granule form seeded with human umbilical cord perivascular cells (HUCPVCs) was evaluated in vitro and in vivo. Indeed, the main goal of this study was to improve the osteogenenic and angiogenic properties of bioactive glasses through the incorporation of strontium and cobalt ions in the glass composition. Although some researches have been conducted on this subject, the influence of the simultaneous use of strontium and cobalt ions on the improvement of bone healing in vivo has been not yet well understood and, therefore, deserves further investigation.

Acceleration of bone regeneration in bioactive glass/gelatin composite scaffolds seeded with bone marrow-derived mesenchymal stem cells over-expressing bone morphogenetic protein-7

In this research, the osteoinduction effect of a novel variant of bone morphogenetic protein-7 (BMP-7), delivered through bone marrow mesenchymal stem cells (BM-MSCs) seeded on bioactive glass/gelatin nanocomposite scaffolds, was evaluated in a calvarial critical size defect in rats. After being harvested and characterized in vitro, BM-MSCs were infected by a plasmid vector containing BMP-7 encoding gene enriched with a heparin-binding site (B2BMP-7) to assess its osteogenic effects in vivo. The animals were randomly categorized into three groups receiving the scaffold alone (group I), the scaffold seeded with BM-MSCs (group II), and the scaffold seeded with manipulated BM-MSCs (group III). After 2, 4 and 12 postoperative weeks, the animals were sacrificed and the harvested specimens were analyzed using histological and immunohistochemical staining. The results of in vitro tests (preliminary screening) showed that the synthesized scaffolds were biocompatible constructs supporting cell attachment and expansion. The in vivo results revealed higher osteogenesis in the defects filled with the B2BMP-7 excreting BM-MSCs/scaffolds compared to the other two groups. After 12weeks of implantation, fully mature newly formed bone was detected throughout the damaged site, which indicates a synergistic effect of cells, scaffolds and growth factors in the process of tissue regeneration. Therefore, bioactive glass-containing scaffolds pre-seeded with manipulated BM-MSCs exhibit an effective combination to improve osteogenesis in bone defects, and the approach followed in this work could have a significant impact in the development of novel tissue engineering constructs.

Effects of Polygonum aviculare herbal extract on sperm parameters after EMF exposure in mouse

Electromagnetic fields with high energy same as ionizing radiation inserts their destructive effects via free radical production. Using antioxidants or herbal plants with antioxidants components could diminish hazardous effects of EMF. Polygonum aviculare has a high amount of phenolic and flavonoid and proved that has antioxidants effects. The aim of this study was to evaluate the effects of Polygonum aviculare herbal extract on sperm parameters after EMF exposure in mouse. Twenty four male mice, 8 weeks divided to 4 groups (one control and three experimental groups). Control group didn't receive EMF exposure. EMF group mice received 3 mT EMF during 2 months, 4 h daily and 5 days weekly. Polygonum aviculare group received 50 mg kg(-1) herbal extract during 2 months and poly -EMF group received 3 mT EMF during 2 months, 4 h daily and 5 days weekly and 50 mg kg(-1) herbal extract during 2 months. After 2 months the mice sacrificed with cervical dislocation and sperm obtained from tail of epididymis and motility and morphology of them were analyzed. Sperm analysis results showed that in group with Polygonum aviculare, morphology and motility of sperm developed (p < 0.05). Present results showed that EMF can reduce motility of sperm and treatment of Polygonum aviculare after EMF exposure developed sperm quality after EMF exposure.