An In Vitro Study of the Effects of Crocin on the Modulation of DSPP, VEGF-A, HLA-G5, STAT3 and CD200 Expression in Human Dental Pulp Stem Cells

The immunoregulatory property of mesenchymal stem cells in Crocin treatment by expression modulation of microRNA-155, microRNA-21, microRNA-23b, microRNA-126a, and their target inflammatory genes

Mesenchymal stem cells (MSCs) have high priority in clinical applications for treatment of immune disorders because of their immunomodulatory function. A lot of researches have currently been undertaken to enhance the stemness capacities of the cells and pick an excellent type of MSCs for clinical approaches. This study aims to assess the immunomodulatory related MicroRNAs (miRNAs) expression as well as their target genes in both adipose derived stem cells (Ad-SCs) and dental pulp derived stem cell (DP-SCs) in the presence or lack of Crocin (saffron plant's bioactive compound). For this purpose, first MSCs were extracted from adipose and dental pulp tissues, and then their mesenchymal nature was confirmed using flow cytometry and differentiation tests. Following the cell treatment with an optimal-non-toxic dose of Crocin (Obtained by MTT test), the expression of 4 selected immunomodulatory-related micro-RNAs (Mir-126, -21, -23, and-155) and their target genes (PI3K/ Akt 1 and 2/ NFKB and RELA) were assessed by RT-PCR. Our findings revealed that miRNA-23 and miRNA-126 were up-regulated in both types of cells treated with Crocin, while in the other side, miRNA-21 and miRNA-155 were down-regulated in DP-SCs and were up-regulated in Ad-SCs under treatment. Moreover, the real-time PCR results indicated that Crocin could significantly down regulate the expression of PI3K/ Akt1/ Akt2/ NFKB/ RELA genes in DP-SCs and PI3K/Akt2 genes in Ad-SCs and up regulate the expression of Akt1/ NFKB/ RELA genes in recent cells. Based on the analysis of the obtained data, the immunoregulatory effects of Crocin were higher in DP-SCs than in Ad-SCs. In conclusion, Crocin could control essential signaling pathways related to the inflammation by regulating the expression of related- miRNAs genes that play a key function in the immune regulation pathways in MSCs. Our findings can give an understanding of the mechanisms by which Crocin enhances the immunomodulatory feature of MSCs. According to the research findings, DP-SCs are probably a better immunomodulator in Crocin treatment than Ad-SCs and it may be helpful for MSCs selection in clinical applications for modulation or treatment of autoimmune disorders.

Osteogenic effect of crocin in human periodontal ligament stem cells via Wnt/β-catenin signaling

OBJECTIVES

Crocin is a major class of medicinal components in saffron. This study aimed to determine whether crocin directly promotes the proliferation and osteogenic differentiation of human periodontal ligament stem cells (PDLSCs) in vitro and in vivo.

MATERIALS AND METHODS

CCK8 cell proliferation assay, reverse transcription quantitative polymerase chain reaction (RT-qPCR), Western blot analysis and Alizarin Red staining were performed in PDLSCs using crocin as a stimulant. DKK1 was used to selectively inhibit Wnt/β-catenin signaling, and Western blotting was performed to investigate the underlying mechanism. The PDLSCs were mixed with calcium phosphate cement and implanted into nude mice subcutaneously to study the effect of crocin on PDLSC osteogenic differentiation in vivo.

RESULTS

The CCK-8 assay showed that crocin did not promote the proliferation of PDLSCs. Treatment with 400 μM crocin significantly promoted PDLSC mRNA levels of ALP, COL1 and OCN; RUNX2 and BMP2 protein expression; mineralized nodule formation in vitro and in vivo; and ALP activity in tissues in vivo. In addition, crocin significantly promoted the phosphorylation of β-catenin and cyclin D1. DKK1 inhibits Wnt/β-catenin activation and partially reverses crocin-mediated promotion of PDLSC osteogenic differentiation.

CONCLUSION

Crocin may contribute to the regeneration of periodontal bone tissue.

Accelerating synergistic effects of preconditioned mesenchymal stem cells with Crocin and dexamethasone in pulmonary epithelial cells injury

Chemical warfare victims suffer from bronchiolitis and chronic pulmonary obstruction caused by sulfur mustard (SM) toxicity. Despite the mesenchymal stem cells capacity to alleviate inflammation, their low survival rate under oxidative stress severely limits their effectiveness. This study aimed to examine how natural (Crocin) and synthetic (Dexamethasone) antioxidants might affect MSC efficacy. MSCs were treated with the optimal doses of Crocin (Cr.), Dexamethasone (Dex.), and their combination. The A549 cells line was pretreated with the optimal dose of the CEES to mimic the lung disease. Then, the affected A549 cells were exposed to the preconditioned MSCs and conditioned media, and then their survival rates were estimated by MTTor2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Annexin-V PI apoptosis test was conducted for MSCs and A549 cells. Reactive Oxygen Species (ROS) assay and Enzyme-linked immunosorbent assay (ELISA) test demonstrated the percentage of production of ROS and the cytokines levels in A549/CEES, respectively. The results revealed significant increases in Cr. + Dex. treated MSCs (P < .01) and A549 cells treated with MSCs-CM/Cr/Dex (P < .01) groups' survival. The apoptosis rate and ROS production were reduced in the MSCs-CM/Cr/Dex. Also, considerable decreases in IL-1β (P < .01) and IL-6 (P < .01) and a significant increase in IL-10 (P < .05) in treated A549/CEES by Cr/Dex and MSCs-CM/Cr/Dex supported the synergistic effects of Crocin and Dexamethasone.

Effects of hydroxyapatite nanorods prepared through Elaeagnus Angustifolia extract on modulating immunomodulatory/dentin-pulp regeneration genes in DPSCs

Dental pulp stem cells (DPSCs) are a new type of mesenchymal stem cells (MSCs) found in the oral cavity with immunomodulation and tissue regeneration capacities. This study determined the impacts of nano-hydroxyapatite (nHA) prepared through Elaeagnus Angustifolia extract (EAE) to enhance the relative expression of immunomodulatory/dentin-pulp regeneration genes in DPSCs. To produce nHA and modified nHA via EAE (nHAEA), the sol-gel technique was used. The functional groups of nanoparticles (NPs), morphological, and optical features were determined using Fourier transform infrared (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) together with energy-dispersive X-ray analysis (EDAX), and Transmission electron microscopy (TEM). The cell viability was then determined using the MTT method in the presence of various EAE, nHA, and nHAEA concentrations. Target gene expression was quantified using a real-time PCR procedure after treating DPSCs with an optimally non-toxic dose of EAE and NPs. The presence of the HA phase was reported with the XRD and FTIR results. According to the results of SEM and TEM, the rod-like NPs could be fabricated. nHAEAs were found to be characterized with low crystallite size, reduced diameter, lengthier, needle-like, and less agglomerated particles compared with nHA. The real-time PCR results demonstrated that nHAEA remarkably increased the expression of human leukocyte antigen-G5 (HLA-G5), vascular endothelial growth factor (VEGF), dentin sialophosphoprotein (DSPP), and interleukin6 (IL6) genes compared to the nHA group. These findings suggest that nHAEAs might have the potential application in the stemness capability of DPSCs for the treatment of inflamed/damaged pulp.

Effect of HM-Exos on the migration and inflammatory response of LPS-exposed dental pulp stem cells

AIM

The purpose of this study was to investigate the effects of human milk exosomes (HM-Exos) on the viability, migration, and inflammatory responses of lipopolysaccharide (LPS)-exposed human dental pulp stem cells (HDPSCs) in vitro.

METHODS

HM-Exos were isolated, and dynamic light scattering (DLS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to analyze their physical properties (size and shape). To construct an in vitro inflammation model, HDPSCs were exposed to LPS. The MTT test and migration assay were used to investigate the effect of HM-Exos on cell proliferation and migration, and the quantitative polymerase chain reaction (qPCR) was used to assess the expression of inflammatory genes in HDPSCs. Data were analyzed using a one-way analysis of variance (ANOVA) with Tukey's post-test.

RESULTS

DLS measurement revealed that HM-Exos were 116.8 ± 3.6 nm in diameter. The SEM and TEM images revealed spherical shapes with diameters of 97.2 ± 34.6 nm. According to the results of the cell viability assay, the nontoxic concentration of HM-Exos (200 µg/ml) was chosen for the subsequent investigations. The migration assay results showed that HM-Exos improved the potential of LPS-exposed HDPSCs to migrate. The qPCR results indicated that HM-Exos significantly reduced the expression of inflammatory cytokines such as TNF-α, IL-1β, and IL-6 in HDPSCs after LPS stimulation.

CONCLUSIONS

HM-Exos increased LPS-exposed HDPSCs migration and proliferation and reduced gene expression of inflammatory cytokines. They may be a viable candidate for pulpitis therapy.

Dentin regeneration based on tooth tissue engineering: A review

Missing or damaged teeth due to caries, genetic disorders, oral cancer, or infection may contribute to physical and mental impairment that reduces the quality of life. Despite major progress in dental tissue repair and those replacing missing teeth with prostheses, clinical treatments are not yet entirely satisfactory, as they do not regenerate tissues with natural teeth features. Therefore, much of the focus has centered on tissue engineering (TE) based on dental stem/progenitor cells to create bioengineered dental tissues. Many in vitro and in vivo studies have shown the use of cells in regenerating sections of a tooth or a whole tooth. Tooth tissue engineering (TTE), as a promising method for dental tissue regeneration, can form durable biological substitutes for soft and mineralized dental tissues. The cell-based TE approach, which directly seeds cells and bioactive components onto the biodegradable scaffolds, is currently the most potential method. Three essential components of this strategy are cells, scaffolds, and growth factors (GFs). This study investigates dentin regeneration after an injury such as caries using TE and stem/progenitor cell-based strategies. We begin by discussing about the biological structure of a dentin and dentinogenesis. The engineering of teeth requires knowledge of the processes that underlie the growth of an organ or tissue. Then, the three fundamental requirements for dentin regeneration, namely cell sources, GFs, and scaffolds are covered in the current study, which may ultimately lead to new insights in this field.

Effect of PCL/nHAEA nanocomposite to osteo/odontogenic differentiation of dental pulp stem cells

Purpose

The green synthesis of nanoparticles has recently opened up a new route in material production. The aim of this study was to evaluate the effect of nanohydroxyapatite (nHA) synthesized from Elaeagnus angustifolia (EA) extract in polycaprolactone (PCL) nanofibers (PCL/nHAEA) to odontogenic differentiation of dental pulp stem cells (DPSCs) and their potential applications for dentin tissue engineering.

Methods

Green synthesis of nHA via EA extract (nHAEA) was done by the sol–gel technique. Then electrospun nanocomposites containing of PCL blended with nHA (P/nHA) and nHAEA (P/nHAEA) were fabricated, and the characterization was evaluated via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and the contact angle. The morphology of nanofibers and the cell adhesion capacity of DPSCs on nanofibers were evaluated using SEM. Cytocompatibility was assessed by MTT. Osteo/odontogenic differentiation ability of the nanocomposites were assessed using alkaline phosphatase (ALP) activity, alizarin red S (ARS) staining, and quantitative real-time polymerase chain reaction (qPCR) technique.

Results

Viability and adhesion capacity of DPSCs were higher on P/nHAEA nanofibers than PCL and P/nHA nanofibers. ARS assay, ALP activity, and qPCR analysis findings confirmed that the nHAEA blended nanofibrous scaffolds substantially increased osteo/odontogenic differentiation of DPSCs.

Conclusion

PCL/nHAEA nanocomposites had a noticeable effect on the odontogenic differentiation of DPSCs and may help to improve cell-based dentin regeneration therapies in the future.

An evaluation on potential anti-oxidant and anti-inflammatory effects of Crocin

Crocin, an active ingredient derived from saffron, is one of the herbal components that has recently been considered by researchers. Crocin has been shown to have many anti-inflammatory and antioxidant properties, and therefore can be used to treat various diseases. It has been shown that Crocin has a positive effect on the prevention and treatment of cardiovascular disease, cancer, diabetes, and kidney disease. In addition, the role of this substance in COVID-19 pandemic has been identified. In this review article, we tried to have a comprehensive review of the antioxidant and anti-inflammatory effects of Crocin in different diseases and different tissues. In conclusion, Crocin may be helpful in pathological conditions that are associated with inflammation and oxidative stress.

Expression of immunomodulatory and tissue regenerative biomarkers in human dental pulp derived-mesenchymal stem cells treated with curcumin: an in vitro study

BACKGROUND

Human Dental pulp derived-mesenchymal stem cells (hDP-MSCs) have the capability of selfrenewal, multipotency, as well as immunosuppressive properties. They are ideal candidates for regenerating damaged dental tissue and treating inflammation-related diseases. However, methods (such as genetic variation) to improve the immunomodulatory and regenerative efficiency of MSCs in different diseases still need to be developed. Curcumin (CUR) is known for its broad applications in regenerative medicine and the treatment of inflammatory disorders via its anti-inflammatory and anti-oxidant effects. This study was conducted to investigate the effect and underlying mechanisms of CUR on the immunomodulatory and regenerative function of hDP-MSCs and whether treating these cells with CUR can improve therapeutic efficacy.

METHODS AND RESULTS

hDP-MSCs were isolated from dental pulp and then treated with CUR. Cell viability rate was observed in hDP-MSCs after treatment of CUR by MTT assay. Real-time quantitative (RT-PCR) was applied to estimate the expression of immunomodulatory and regenerative genes after treatment of CUR. The RT-PCR results showed that VEGF-A and STAT3 markers were up-regulated while HLA-G5 and VCAM-1 markers were down-regulated by CUR (20 µM) treatment in hDP-MSCs (P < 0.001). Besides, this research indicated that there were no significant changes in the expressions of RelA and DSPP after 48 h (P = 0.33, P = 1).

CONCLUSION

Our findings demonstrate that CUR can enhance the immunomodulatory and regenerative effects of hDP-MSCs and improve their therapeutic efficacy. These findings can give an understanding of the mechanism for improving restorative and immunomodulatory activity in hDP-MSCs by curcumin.