Combination of natural scaffolds and conditional medium to induce the differentiation of adipose-derived mesenchymal stem cells into keratocyte-like cells and its safety evaluation in the animal cornea

Melissa officinalis extract nanoemulsion, Caffeic acid and Quercetin as a novel inducer for investigating neural differentiation of human Wharton's jelly mesenchymal stem cells

BACKGROUND

Cell therapy utilizing mesenchymal stem cells, which have the ability to differentiate into different lineages, has garnered significant attention in recent years. Melissa officinalis is rich in biologically active compounds and exhibits antioxidant activity, antimicrobial properties, and sedative effects. Nanoemulsions can facilitate the effective transfer of substances and also protect drugs and biological materials from environmental factors. The aim of the present study is to investigate the role of Melissa officinalis extract nanoemulsion and the active ingredients of caffeic acid and quercetin as inducers in increasing the efficiency of differentiation of mesenchymal stem cells into neural cells in a laboratory environment.

MATERIALS AND METHODS

Human WJMSCs were cultured in the basic culture medium consisting of: Hight glucose DMEM, 10 % FBS and 1 % penicillin/streptomycin. The alcoholic extract of Melissa officinalis was extracted and its nanoemulsion was prepared along with two other effective substances. Next, zeta potential and size of nanoparticles were measured by Dynamic light scattering (DLS) technique. The optimal dose of all three material was calculated by MTT (3-4,5-dimethylthiazol-2-yl-2, 5-diphenyl tetrazolium bromide) assay and Acridine orange-ethidium bromide (AO/EB) staining. In the following, neural differentiation was investigated using Real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR) and immunocytochemistry (ICC) techniques on days 7 and 14.

RESULTS

The results obtained from MTT and AO/EB assays showed that the optimal dose of nanoemulsion M. officinalis, caffeic acid and quercetin is 150 μg/ml, 75 μg/ml and 25 μg/ml, respectively. The ideal particle size for nanoemulsion is below 100 nm. The zeta potential of the M. officinalis extract nanoemulsion was reported to be -9.45 and the average particle size was 17.76 nm. The results of this study indicated that the expression of neural marker genes (MAP-2, β-tubulin III and NSE) and proteins (MAP-2, β-tubulin III and Gamma-enolase) increased in differentiated cells treated with the synthesized nanoemulsion compared to the control group on days 7 and 14 (P ≤ 0.05).

CONCLUSION

In general, our results showed that M. officinalis extract nanoemulsion, caffeic acid and quercetin caused induction of neural differentiation mechanism in human WJ-MSCs.

Investigating the enhancement of neural differentiation of adipose-derived mesenchymal stem cell with Foeniculum vulgare nanoemulsions: An in vitro research

BACKGROUND

Neurons, distributed throughout the body, regulate various bodily functions. The recovery of the nervous system is often slow and can be irreversible. Currently, the approach of using mesenchymal stem cells (MSCs) in conjunction with conventional treatments for nervous system injuries is being explored. Nanoemulsions are systems designed for the nanoscale delivery of drug cargoes. Foeniculum vulgare (F. vulgare), a medicinal plant long utilized in complementary medicine, is the focus of this study. The aim is to utilize nanoemulsions of fennel to induce the differentiation of MSCs into neural-like cells in vitro.

MATERIALS AND METHODS

Human adipose-derived mesenchymal stem cells (hADSCs) were commercially purchased. These cells were cultured in DMEM medium containing 10 % fetal bovine serum and 1 % penicillin-streptomycin antibiotic. Based on a sequential extraction method, n-hexane (Hex), ethyl acetate (EtAc), and ethanolic extracts were obtained from the seeds of F. vulgare. To prepare the F. vulgare extract nanoemulsion, the aqueous phase (distilled water), the oily part (F. vulgare extract), Span 80 and Tween 20 were used. The optimal dose of F. vulgare nanoemulsion was determined using the MTT assay and acridine orange/ethidium bromide (AO/EB) staining. Neural differentiation was induced using a specialized differentiation medium on the MSCs, with the prepared nanoemulsions acting as inducers. The neural differentiation of the human differentiated hADSCs was studied and evaluated through Real-time PCR and immunocytochemistry (ICC) techniques on days 7 and 14.

RESULTS

The results obtained from the MTT and AO/EB tests indicated that the optimal dose of F. vulgare nanoemulsions is 1 μg/ml. Analysis of neural differentiation index gene expression revealed a significant (P ≤ 0.05) upregulation of MAP-2, β-tubulin III, and NSE genes on days 7 and 14 following treatment with the nanoemulsions. It is noteworthy that the nanoemulsion prepared from the hexane extract of the plant showed a significant increase in the expression of marker genes in the process of neural differentiation. Protein expression analysis demonstrated an increase in MAP-2, β-tubulin III, and NSE (gamma enolase) proteins in response to the nanoemulsion inducers compared to the control group (TCPS).

DISCUSSION

Overall, our findings indicate that F. vulgare nanoemulsions have a positive effect on the expression of genes and proteins related to neural differentiation in hADSCs. The proposed protocol may serve as a potential therapeutic strategy in complementary medicine for patients seeking to improve injuries to the nervous system. However, further studies and performance measurements are necessary in future research to confirm these results.

Layered double hydroxides for regenerative nanomedicine and tissue engineering: recent advances and future perspectives

With the rapid development of nanotechnology, layered double hydroxides (LDHs) have attracted considerable attention in the biomedical field due to their highly tunable composition and structure, superior biocompatibility, multifunctional bioactivity, and exceptional drug delivery performance. However, a focused and comprehensive review addressing the role of LDHs specifically in tissue regeneration has been lacking. This review aims to fill that gap by providing a systematic and in-depth overview of recent advances in the application of LDHs across various regenerative domains, including bone repair, cartilage reconstruction, angiogenesis, wound healing, and nerve regeneration. Beyond presenting emerging applications, the review places particular emphasis on elucidating the underlying mechanisms through which LDHs exert their therapeutic effects. Although LDHs demonstrate considerable promise in regenerative medicine, their clinical translation remains in its infancy. To address this, we not only provided our insights into the personalized problems that arise in the application of various tissues, but also focused on discussing and prospecting the common challenges in the clinical translation of LDHs. These challenges include optimizing synthesis techniques, enhancing biosafety and stability, improving drug-loading efficiency, designing multifunctional composite materials, and establishing pathways that facilitate the transition from laboratory research to clinical practice.

Decellularization of human iliac artery: A vascular scaffold for peripheral repairs with human mesenchymal cells

This work presents strong evidence supporting the use of decellularized human iliac arteries combined with adipose tissue-derived stem cells (hASCs) as a promising alternative for vascular tissue engineering, opening the path to future treatments for peripheral artery disease (PAD). PAD is a progressive condition with high rates of amputation and mortality due to ischemic damage and limited graft options. Traditional synthetic grafts often fail due to poor integration, while autologous grafts may be unsuitable for patients with compromised vascular health. This study explores the potential of decellularized human iliac arteries as scaffolds for vascular grafts, focusing on preserving extracellular matrix (ECM) ultrastructure while minimizing immunogenic response. A perfusion-based protocol with enzymatic and detergent agents effectively removed cellular material, resulting in scaffolds with preserved ECM architecture, including organized collagen and elastin fibers. To assess scaffold bioactivity, hASCs were seeded onto the decellularized ECM, demonstrating high viability. Structural assessments, including histological staining and mechanical testing, confirmed that decellularized arteries retained their hierarchical structure and exhibited increased stiffness, suggesting an adaptive realignment of ECM fibers. Thermal and ultrastructural analyses further showed that decellularized scaffolds maintained stability and integrity comparable to native tissue, underscoring their durability for clinical applications. The human iliac artery shows potential as a vascular scaffold due to its accessibility and the ability to support the viability of hASC. Future research will emphasize in vivo validation and strategies for functional recellularization to evaluate the clinical viability of these engineered vascular grafts.

Mesenchymal stem cells and mesenchymal stem cell-derived exosomes: a promising strategy for treating retinal degenerative diseases

Mesenchymal stem cells (MSCs) have emerged as a promising therapeutic strategy in regenerative medicine, demonstrating significant potential for clinical applications. Evidence suggests that MSCs not only exhibit multipotent differentiation potential but also exert critical therapeutic effects in retinal degenerative diseases via robust paracrine mechanisms. MSCs protect retinal cells from degenerative damage by modulating inflammation, inhibiting apoptosis, alleviating oxidative stress, and suppressing cell death pathways. Furthermore, MSCs contribute to retinal structural and functional stability by facilitating vascular remodeling and donating mitochondria to retinal cells. Of particular interest, MSC-derived exosomes have gained widespread attention as a compelling cell-free therapy. Owing to their potent anti-inflammatory, anti-apoptotic, and vascular-stabilizing properties, exosomes show significant promise for the treatment of retinal degenerative diseases.

Tissue engineering strategies for ocular regeneration; from bench to the bedside

Millions globally suffer from visual impairment, complicating the management of eye diseases due to various ocular barriers. The eye's complex structure and the limitations of existing treatments have spurred interest in tissue engineering (TE) as a solution. This approach offers new functionalities and improves therapeutic outcomes over traditional drug delivery methods, creating opportunities for treating various eye disorders, from corneal injuries to retinal degeneration. In our review of recent articles concerning the use of scaffolds for eye repair, we categorized scaffolds employed in eye TE from recent studies into four types based on tissue characteristics: natural, synthetic, biohybrid, and decellularized tissue. Additionally, we gathered data on the cell types and animal models associated with each scaffold. This allowed us to gather valuable insights into the benefits and drawbacks of each material. Our research elucidates that, in comparison to conventional treatment modalities, scaffolds in TE emulate the extracellular matrix (ECM) of the eye and facilitate cell proliferation and tissue regeneration. These scaffolds can be precisely tailored to incorporate growth factors that augment the healing process while also providing considerable advantages such as bacterial inhibition, biocompatibility, and enhanced durability. However, they also have drawbacks, such as potential immune responses, poor tissue integration, complex and costly manufacturing, and inconsistent degradation rates that can affect their effectiveness. In this review, we provide an overview of the present condition of eye regenerative treatments, assess notable preclinical and clinical research endeavors, contemplate the obstacles encountered, and speculate on potential advancements in the upcoming decade.

Development of a Composite Hydrogel Containing Statistically Optimized PDGF-Loaded Polymeric Nanospheres for Skin Regeneration: In Vitro Evaluation and Stem Cell Differentiation Studies

Platelet-derived growth factor-BB (PDGF-BB) is a polypeptide growth factor generated by platelet granules faced to cytokines. It plays a role in forming and remodeling various tissue types, including epithelial tissue, through interaction with cell-surface receptors on most mesenchymal origin cells. However, it breaks down quickly in biological fluids, emphasizing the importance of preserving them from biodegradation. To address this challenge, we formulated and evaluated PDGF-encapsulated nanospheres (PD@PCEC) using polycaprolactone-polyethylene glycol-polycaprolactone. PD@PCECs were fabricated through the triple emulsion methodology and optimized by using the Box-Behnken design. The encapsulation efficiency (EE) of nanoencapsulated PDGF-BB was investigated concerning four variables: stirring rate (X1), stirring duration (X2), poly(vinyl alcohol) concentration (X3), and PDGF-BB concentration (X4). The selected optimized nanospheres were integrated into a gelatin-collagen scaffold (PD@PCEC@GC) and assessed for morphology, biocompatibility, in vitro release, and differentiation-inducing activity in human adipose-derived stem cells (hADSCs). The optimized PD@PCEC nanospheres exhibited a particle size of 177.9 ± 91 nm, a zeta potential of 5.2 mV, and an EE of 87.7 ± 0.44%. The release profile demonstrated approximately 85% of loaded PDGF-BB released during the first 360 h, with a sustained release over the entire 504 h period, maintaining bioactivity of 87.3%. The study also included an evaluation of the physicochemical properties of the scaffolds and an assessment of hADSC adhesion to the scaffold's surface. Additionally, hADSCs cultivated within the scaffold effectively differentiated into keratinocyte-like cells (KLCs) over 21 days, evidenced by morphological changes and upregulation of keratinocyte-specific genes, including cytokeratin 18, cytokeratin 19, and involucrin, at both transcriptional and protein levels.

An inspired microenvironment of cell replicas to induce stem cells into keratocyte-like dendritic cells for corneal regeneration

Corneal stromal disorders due to the loss of keratocytes can affect visual impairment and blindness. Corneal cell therapy is a promising therapeutic strategy for healing corneal tissue or even enhancing corneal function upon advanced disorders, however, the sources of corneal keratocytes are limited for clinical applications. Here, the capacity of cell-imprinted substrates fabricated by molding human keratocyte templates to induce differentiation of human adipose-derived stem cells (hADSCs) into keratocytes, is presented. Keratocytes are isolated from human corneal stroma and grown to transmit their ECM architecture and cell-like topographies to a PDMS substrate. The hADSCs are then seeded on cell-imprinted substrates and their differentiation to keratocytes in DMEM/F12 (with and without chemical factors) are evaluated by real-time PCR and immunocytochemistry. The mesenchymal stem cells grown on patterned substrates present gene and protein expression profiles similar to corneal keratocytes. In contrast, a negligible expression of myofibroblast marker in the hADSCs cultivated on the imprinted substrates, is observed. Microscopic analysis reveals dendritic morphology and ellipsoid nuclei similar to primary keratocytes. Overall, it is demonstrated that biomimetic imprinted substrates would be a sufficient driver to solely direct the stem cell fate toward target cells which is a significant achievement toward corneal regeneration.