Photobiostimulation conjugated with stem cells or their secretome for temporomandibular joint arthritis in a rat model.

BACKGROUND: Temporomandibular joint (TMJ) arthritis is a debilitating, challenging condition and different methods have been implicated for its treatment. This study aimed to test the therapeutic potentials of low-level laser therapy (LLLT) associated with adipose derived stem cells (ADSC) or their derived secretome on a murine model induced arthritis. METHODS: Forty eight rats were divided into four groups where group I was the sham control, the rest of animals were subjected to arthritis induction using complete Freund's adjuvant, then divided as follows: group II received phosphate buffered saline (PBS) intraarticular injection and irradiation of 0 j/cm2, group III received ADSCs derived secretome and irradiation of 38 j/cm2, and group IV received ADSCs and irradiation of 38 j/cm2 as well. One and three weeks after treatment, animals were euthanized, and paraffin blocks were processed for histological assessment by hematoxylin and eosin stain with histomorphometrical analysis. Histochemical evaluation of joint proteoglycan content was performed through toluidine blue stain, and immunohistochemical staining by the proinflammatory marker tumor necrosis factor-α (TNF-α) was performed followed by the relevant statistical tests. RESULTS: The arthritis group showed histological signs of joint injury including cartilage atrophy, articular disc fibrosis, irregular osteochondral interface, and condylar bone resorption together with high inflammatory reaction and defective proteoglycan content. In contrast, the treated groups III and IV showed much restoration of the joint structure with normal cartilage and disc thickness. The inflammation process was significantly suppressed especially after three weeks as confirmed by the significant reduction in TNF-α positive immunostaining compared to the arthritic group, and the cartilage proteoglycan content also showed significant increase relative to the arthritic group. However, no significant difference between the results of the two treated groups was detected. CONCLUSION: LLLT conjugated with ADSCs or ADSCs derived secretome can efficiently enhance the healing of arthritic TMJs. Stem cell secretome can be applied as a safe, potent therapy. However, further investigations are required to unravel its mechanism of action and pave its way as a safe, novel, cell free therapy.

Emerging therapeutic modality enhancing the efficiency of chemotherapeutic agents against head and neck squamous cell carcinoma cell lines.

The current work aimed to evaluate bee venom (BV) cytotoxic effect and its synergistic action when combined with cisplatin (CIS) against four types of head and neck squamous cell carcinoma (HNSCC) cell lines. 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide (MTT) assay for cell viability, reverse transcription-polymerase chain reaction (RT-PCR) for expression of BCL2 associated X (BAX), B-cell lymphoma 2 (BCL2) and epidermal growth factor receptor (EGFR) genes and, flow cytometry for cell cycle analysis were performed. MTT assay revealed that BV caused an approximately 50% cell death for UMSCC12, UMSCC29, UMSCC38 and, UMSCC47 cell lines after 72 hr with 54.809 µg/ml, 61.287 µg/ml, 71.328 µg/ml and, 61.045 µg/ml, respectively. RT-PCR demonstrated a significant up-regulation of BAX gene and a significant down-regulation of BCL2 and EGFR genes among single or combined treatments with CIS and BV as compared to vehicle-treated. The cell lines treated with both BV and CIS showed marked elevation of BAX and a notable drop of BCL2 and EGFR expressions than single-treated groups. Cell cycle analysis via flow cytometry revealed significantly increased cells in the G2/M phase in single or combined-treated cell lines with CIS and BV when compared with vehicle-treated. Moreover, a significant decrease in cells in S phases among all single and combined treatments when matched with vehicle-treated. Briefly, the findings of the present study suggest that BV can exert an anti-cancer effect on HNSCC and may have the potentiality for potentiation of CIS cytotoxic effects and reduction of its adverse effects.

Evaluation of the osteogenic potential of rat adipose-derived stem cells with different polycaprolactone/alginate-based nanofibrous scaffolds: an in vitro study.

BACKGROUND: Bone tissue engineering is a widely growing field that requires the combination of cells, scaffolds and signaling molecules. Adipose derived stem cells (ADSCs) are an accessible and abundant source of mesenchymal stem cells with high plasticity. Polycaprolactone/alginate (PCL/Alg) composite scaffolds have been used in bone regeneration and nano-hydroxyapatite (n-HA) is used as a reinforcing, osteoconductive component in scaffold fabrication. This study was conducted to assess the ability of three different PCL/Alg based scaffolds to induce osteogenic differentiation of ADSCs and to compare between them. METHODS: The study comprised 5 groups; negative control group with ADSCs cultured in complete culture media, positive control group with ADSCs cultured in osteogenic differentiation media, and 3 experimental groups with ADSCs seeded onto 3 scaffolds: S1 (PCL/Alg), S2 (PCL/Alg/Ca) and S3 (PCL/Alg/Ca/n-HA) respectively and cultured in osteogenic media. Mineralization and gene expression were assessed by Alizarin red S (ARS) staining and real time quantitative polymerase chain reaction (RT-qPCR). Evaluation was done at 7, 14 and 21 days. RESULTS: ARS staining reflected a time dependent increase through days 7, 14 and 21, with S3 (PCL/Alg/Ca/n-HA) group showing the highest mineralization levels. RT-qPCR detected upregulation of ALP gene expression at day 7 and decline thereafter. S2 (PCL/Alg/Ca) and S3 (PCL/Alg/Ca/n-HA) groups showed significantly higher gene expression levels than S1 (PCL/Alg). CONCLUSIONS: ADSCs and PCL/Alg-based scaffolds compose a good tissue engineering complex for bone regeneration. Addition of n-HA to PCL/Alg scaffolds and crosslinking with CaCl2 efficiently improve the osteogenic potential of ADSCs.

The Effect of Different Routes of Injection of Bone Marrow Mesenchymal Stem Cells on Parotid Glands of Rats Receiving Cisplatin: A Comparative Study.

BACKGROUND AND OBJECTIVES: Cisplatin is a powerful antitumor chemotherapeutic agent that is widely used in the treatment of many cancers but it has many side effects on many organs including salivary glands. Bone marrow is considered to be a rich environment that comprises many types of stem cells of which BMSCs (Bone marrow mesenchymal stem cells) are the most studied with potentiality to differentiate into many cell types. This study was conducted to evaluate the effect of different routes of injection of BMSCs on parotid glands of rats receiving cisplatin. METHODS AND RESULTS: Sprague-Dawley rats were divided into 3 groups: a negative control group receiving phosphate buffered saline, a positive control group receiving cisplatin, and an experimental group where rats received cisplatin and then received iron oxide-labeled BMSCs by either intravenous or intraparotid routes or both. Animals were sacrificed at periods of 3,6,10 and 15 days after cisplatin injection, then histological, ultrastructural and immunohistochemical studies were done. The experimental stem cell treated group showed better histological features and increased PCNA proliferation index when compared to the control. The systemic and combination groups showed better results than the local group. Iron oxide-labeled cells were detected with Prussian blue stain. CONCLUSIONS: This study proved that BMSCs can improve cisplatin induced cytotoxicity in parotid glands. Systemic administration showed to have a better effect than local intraparotid administration and comparable effect to combined administration.