Therapeutic Efficiency of Nasal Mucosa-Derived Ectodermal Mesenchymal Stem Cells in Rats with Acute Hepatic Failure

Fibrin-konjac glucomannan-black phosphorus hydrogel scaffolds loaded with nasal ectodermal mesenchymal stem cells accelerated alveolar bone regeneration

BACKGROUND

Effective treatments for the alveolar bone defect remain a major concern in dental therapy. The objectives of this study were to develop a fibrin and konjac glucomannan (KGM) composite hydrogel as scaffolds for the osteogenesis of nasal mucosa-derived ectodermal mesenchymal stem cells (EMSCs) for the regeneration of alveolar bone defect, and to investigate the osteogenesis-accelerating effects of black phosphorus nanoparticles (BPNs) embedded in the hydrogels.

METHODS

Primary EMSCs were isolated from rat nasal mucosa and used for the alveolar bone recovery. Fibrin and KGM were prepared in different ratios for osteomimetic hydrogel scaffolds, and the optimal ratio was determined by mechanical properties and biocompatibility analysis. Then, the optimal hydrogels were integrated with BPNs to obtain BPNs/fibrin-KGM hydrogels, and the effects on osteogenic EMSCs in vitro were evaluated. To explore the osteogenesis-enhancing effects of hydrogels in vivo, the BPNs/fibrin-KGM scaffolds combined with EMSCs were implanted to a rat model of alveolar bone defect. Micro-computed tomography (CT), histological examination, real-time quantitative polymerase chain reaction (RT-qPCR) and western blot were conducted to evaluate the bone morphology and expression of osteogenesis-related genes of the bone regeneration.

RESULTS

The addition of KGM improved the mechanical properties and biodegradation characteristics of the fibrin hydrogels. In vitro, the BPNs-containing compound hydrogel was proved to be biocompatible and capable of enhancing the osteogenesis of EMSCs by upregulating the mineralization and the activity of alkaline phosphatase. In vivo, the micro-CT analysis and histological evaluation demonstrated that rats implanted EMSCs-BPNs/fibrin-KGM hydrogels exhibited the best bone reconstruction. And compared to the model group, the expression of osteogenesis genes including osteopontin (Opn, p < 0.0001), osteocalcin (Ocn, p < 0.0001), type collagen (Col , p < 0.0001), bone morphogenetic protein-2 (Bmp2, p < 0.0001), Smad1 (p = 0.0006), and runt-related transcription factor 2 (Runx2, p < 0.0001) were all significantly upregulated.

CONCLUSIONS

EMSCs/BPNs-containing fibrin-KGM hydrogels accelerated the recovery of the alveolar bone defect in rats by effectively up-regulating the expression of osteogenesis-related genes, promoting the formation and mineralisation of bone matrix.

Rat nasal mucosa-derived ectodermal mesenchymal stem cells: A new therapeutic option for chronic rhinosinusitis

OBJECTIVE

To investigate the effect of nasal mucosa-derived ectodermal mesenchymal stem cells (NM-EMSCs) on the inflammatory state of rats with chronic rhinosinusitis (CRS) and the underlying therapeutic mechanism.

METHODS

NM-EMSCs were isolated and extracted to construct a rat model of CRS. Fifteen Sprague‒Dawley (SD) rats were randomly divided into three groups: CK + NS group rats were injected locally with saline in the nasal mucosa; CRS + NS group rats were injected locally with saline in the nasal mucosa; and CRS + EMSCs group rats were injected locally with NM-EMSCs in the nasal mucosa. One rat from the CRS + EMSCs group was randomly euthanized at 2, 4, and 6 days after injection, and the nasal mucosa tissues were collected for HE staining, Masson's trichrome staining, and periodic acid-Schiff staining.

RESULTS

NM-EMSCs specifically expressing CD73, CD105, and CD90 were successfully isolated from the nasal mucosa of rats and were able to differentiate into adipocytes, osteoblasts, and chondrocytes. After saline and NM-EMSC injection, compared with those in the blank control CK + NS group, the nasal mucosa in the CRS + NS and CRS + EMSC groups exhibited obvious thickening, a large amount of inflammatory cell infiltration, and increased collagen and mucin distribution. Four days post-NM-EMSC injection, the thickening of the nasal mucosa in the CRS group was gradually alleviated, the inflammatory cell infiltration gradually decreased, and the distribution of collagen and mucin and the collagen-positive area gradually decreased. Moreover, only a small number of inflammatory cells were visible, and the distribution of mucins was limited to 6 days post-NM-EMSC injection.

CONCLUSION

NM-EMSCs effectively attenuated inflammation in the nasal mucosa of CRS model rats.

Arctium lappa L. polysaccharides enhanced the therapeutic effects of nasal ectomesenchymal stem cells against liver fibrosis by inhibiting the Wnt/β-catenin pathway

The oxidative microenvironment in fibrotic livers often diminishes the effectiveness of mesenchymal stem cells (MSCs)-based therapy. Recent research suggests that pharmacological pre-treatment could enhance the therapeutic performance of MSCs. In this study, we assessed the impact of Arctium lappa L. polysaccharides (ALP) on the biological properties of nasal ectomesenchymal stem cells (EMSCs) and investigated the augmenting effect of ALP pretreatment on EMSCs (ALP-EMSCs) for the treatment of liver fibrosis. ALP treatment demonstrated multiple biological impacts on EMSC functions regarding liver fibrosis: firstly, it maintained the stemness of the cells while boosting the EMSCs' paracrine effects; secondly, it increased the expression of anti-inflammatory and antioxidant factors; thirdly, it inhibited the activation of hepatic stellate cells (HSCs) and liver collagen build-up by modulating the Wnt/β-catenin signaling pathways. Collectively, these effects helped to halt the progression of liver fibrosis. Therefore, the use of ALP-EMSCs presents an innovative and promising approach for treating hepatic fibrosis in clinical scenarios.

[Exosomes from ectoderm mesenchymal stem cells inhibits lipopolysaccharide-induced microglial M1 polarization and promotes survival of H2O2-exposed PC12 cells by suppressing inflammatory response and oxidative stress]

OBJECTIVE

To investigate the potential value of exosomes derived from rat ectoderm mesenchymal stem cells (EMSCs-exo) for repairing secondary spinal cord injury.

METHODS

EMSCs-exo were obtained using ultracentrifugation from EMSCs isolated from rat nasal mucosa, identified by transmission electron microscope, nanoparticle tracking analysis (NTA), and Western blotting, and quantified using the BCA method. Neonatal rat microglia purified by differential attachment were induced with 100 μg/L lipopolysaccharide (LPS) and treated with 37.5 or 75 mg/L EMSCs-exo. PC12 cells were exposed to 400 μmol/L H2O2 and treated with EMSCs-exo at 37.5 or 75 mg/L. The protein and mRNA expressions of Arg1 and iNOS in the treated cells were determined with Western blotting and qRT- PCR, and the concentrations of IL- 6, IL-10, and IGF-1 in the supernatants were measured with ELISA. The viability and apoptosis of PC12 cells were detected using CCK-8 assay and flow cytometry.

RESULTS

The isolated rat EMSCs showed high expressions of nestin, CD44, CD105, and vimentin. The obtained EMSCs-exo had a typical cup-shaped structure under transmission electron microscope with an average particle size of 142 nm and positivity for CD63, CD81, and TSG101 but not vimentin. In LPS-treated microglia, EMSCs-exo treatment at 75 mg/L significantly increased Arg1 protein level and lowered iNOS protein expression (P < 0.05). EMSCs-exo treatment at 75 mg/L, as compared with the lower concentration at 37.5 mg/L, more strongly increased Arg1 mRNA expression and IGF-1 and IL-10 production and decreased iNOS mRNA expression and IL-6 production in LPS-induced microglia, and more effectively promoted cell survival and decreased apoptosis rate of H2O2-induced PC12 cells (P < 0.05).

CONCLUSION

EMSCs-exo at 75 mg/L can effectively reduce the proportion of M1 microglia and alleviate neuronal apoptosis under oxidative stress to promote neuronal survival, suggesting its potential in controlling secondary spinal cord injury.

Evaluation of the Composite Skin Patch Loaded with Bioactive Functional Factors Derived from Multicellular Spheres of EMSCs for Regeneration of Full-thickness Skin Defects in Rats

BACKGROUND

Transplantation of stem cells/scaffold is an efficient approach for treating tissue injury including full-thickness skin defects. However, the application of stem cells is limited by preservation issues, ethical restriction, low viability, and immune rejection in vivo. The mesenchymal stem cell conditioned medium is abundant in bioactive functional factors, making it a viable alternative to living cells in regeneration medicine.

METHODS

Nasal mucosa-derived ecto-mesenchymal stem cells (EMSCs) of rats were identified and grown in suspension sphere-forming 3D culture. The EMSCs-conditioned medium (EMSCs-CM) was collected, lyophilized, and analyzed for its bioactive components. Next, fibrinogen and chitosan were further mixed and cross-linked with the lyophilized powder to obtain functional skin patches. Their capacity to gradually release bioactive substances and biocompatibility with epidermal cells were assessed in vitro. Finally, a full-thickness skin defect model was established to evaluate the therapeutic efficacy of the skin patch.

RESULTS

The EMSCs-CM contains abundant bioactive proteins including VEGF, KGF, EGF, bFGF, SHH, IL-10, and fibronectin. The bioactive functional composite skin patch containing EMSCs-CM lyophilized powder showed the network-like microstructure could continuously release the bioactive proteins, and possessed ideal biocompatibility with rat epidermal cells in vitro. Transplantation of the composite skin patch could expedite the healing of the full-thickness skin defect by promoting endogenous epidermal stem cell proliferation and skin appendage regeneration in rats.

CONCLUSION

In summary, the bioactive functional composite skin patch containing EMSCs-CM lyophilized powder can effectively accelerate skin repair, which has promising application prospects in the treatment of skin defects.