N2 non-thermal atmospheric pressure plasma promotes wound healing in vitro and in vivo: Potential modulation of adhesion molecules and matrix metalloproteinase-9.

Advances in physics and biology have made it possible to apply non-thermal atmospheric pressure plasma (NTP) in the biomedical field. Although accumulating evidence suggests that NTP has various medicinal effects, such as facilitating skin wound healing on exposed tissue while minimizing undesirable tissue damage, the underlying molecular mechanisms are not fully understood. In this study, NTP generated from N2 optimized wound healing in the scratch wound healing assay. In addition, matrix metalloproteinase (MMP)-9 expression and enzyme activity increased and the urokinase-type plasminogen activator (uPA) system was activated after NTP treatment. We also showed that NTP treatment increased Slug and TCF8/ZEB1 expression and decreased that of E-cadherin, suggesting induction of the epithelial-to-mesenchymal transition (EMT). The effect of N2 NTP was verified on rat wound model. Taken together, these results suggest that N2 NTP promotes wound healing by inducing the EMT and activating the MMP-9/uPA system. These findings show the therapeutic potential of NTP for skin wound healing.

The Psychometric Properties of the Patient Health Questionnaire-9 in a Sample of Korean University Students.

OBJECTIVE: Depressive symptoms among university students are a major mental-health issue worldwide, and university students are particularly vulnerable to various stressors that can produce depression. Therefore, accurate and sustainable assessment of depressive symptoms among university students is of special importance. The Patient Health Questionnaire-9 (PHQ-9) is one such measure. The objective of the current study was to evaluate the psychometric properties of the PHQ-9 among Korean university students. METHODS: A total sample of 582 university students attending a four-year private university in South Korea was recruited for the study. Confirmatory factor analyses (CFAs) were performed to compare the goodness-of-fit of four competing models suggested by extant literature on the PHQ-9. Convergent validity was assessed using a correlation analysis between the PHQ-9 and other psychiatric instruments, including the Depression, Anxiety, and Stress Scale-21 (DASS-21) and the Generalized Anxiety Disorder Scale (GAD-7). RESULTS: A one-factor structure of the PHQ-9 provided the best fit to the data. Internal consistency was adequate. The PHQ-9 demonstrated good convergent validity with related constructs. CONCLUSION: The psychometric properties of the PHQ-9 proved to be adequate, with a robust and interpretable factor structure and good internal consistency. The PHQ-9's validity, reliability, brevity and ease of administration make it a useful screening instrument for depression among university students in Korea.

Opposite effects of non-thermal plasma on cell migration and collagen production in keloid and normal fibroblasts.

Recent progress in the understanding non-thermal plasma (NTP) properties prompted its application in the treatment of various diseases. However, therapeutic effect of NTP on keloid cells has not been reported previously. We sought to investigate the effect of NTP treatment on keloid by comparing cell migration and collagen production of keloid (KFs) and normal fibroblasts (NFs) and determined the regulatory pathways involved. We assessed NTP effects on cell migration in KFs and NFs by the wound healing assay and measured the expression of the epidermal growth factor receptor (EGFR), signal transducer and activator of transcription-3 (STAT3), and collagen by western blot. Expression of the transforming growth factor-ß and Type I collagen following NTP treatment was determined by reverse transcription-polymerase chain reaction, immunofluorescence staining, and the Sircol collagen assay. NTP treatment increased cell migration and collagen production of NFs. However, it reduced these parameters in KFs. NTP reduced the expression of EGFR, STAT3, and Type I collagen in KFs but increased their levels in NFs. We revealed that NTP suppressed KF cell migration via down-regulation of EGFR and STAT3 and reduced collagen production via supressing transforming growth factor-ß. Our data suggest that NTP may be a new therapeutic strategy for keloids.

Novel Therapeutic Effects of Non-thermal atmospheric pressure plasma for Muscle Regeneration and Differentiation.

Skeletal muscle can repair muscle tissue damage, but significant loss of muscle tissue or its long-lasting chronic degeneration makes injured skeletal muscle tissue difficult to restore. It has been demonstrated that non-thermal atmospheric pressure plasma (NTP) can be used in many biological areas including regenerative medicine. Therefore, we determined whether NTP, as a non-contact biological external stimulator that generates biological catalyzers, can induce regeneration of injured muscle without biomaterials. Treatment with NTP in the defected muscle of a Sprague Dawley (SD) rat increased the number of proliferating muscle cells 7 days after plasma treatment (dapt) and rapidly induced formation of muscle tissue and muscle cell differentiation at 14 dapt. In addition, in vitro experiments also showed that NTP could induce muscle cell proliferation and differentiation of human muscle cells. Taken together, our results demonstrated that NTP promotes restoration of muscle defects through control of cell proliferation and differentiation without biological or structural supporters, suggesting that NTP has the potential for use in muscle tissue engineering and regenerative therapies.

Anti-cancer effect of (-)-epigallocatechin-3-gallate (EGCG) in head and neck cancer through repression of transactivation and enhanced degradation of ß-catenin.

BACKGROUND AND PURPOSE: Aberrant expression of ß-catenin is highly associated with progression of various cancers including head and neck cancer (HNC). Green tea is most commonly used beverage in the world and one of the more bioactive compounds is the antioxidant epigallocatechin gallate (EGCG). This study was performed to investigate the mechanism by which EGCG inhibits the growth of HNC, focusing on the modulation of the expression and activity of ß-catenin. METHODS: In vitro effects of EGCG on the transcription, translation, or degradation of ß-catenin were investigated. Antitumor effects of EGCG in vivo were evaluated in a syngeneic mouse model and ß-catenin expression was checked in HNC patients' samples. RESULTS: ß-catenin expression was elevated in tumor samples of HNC patients. EGCG induced apoptosis in KB and FaDu cells through the suppression of ß-catenin signaling. Knockdown of ß-catenin using siRNA enhanced the proapoptotic activities of EGCG. EGCG decreased mRNA and transcriptional activity of ß-catenin in p53 wild-type KB cells. EGCG also enhanced the ubiquitination and proteasomal degradation of ß-catenin. The suppression of ß-catenin and consequent apoptosis were observed in response to EGCG treatment in a syngeneic mouse model. In conclusion, we report that EGCG inhibits ß-catenin expression through multiple mechanisms including decreased transcription and increased ubiquitin-mediated 26S proteasomal degradation. CONCLUSION: This study proposes a novel molecular rationale for antitumor activities of green tea in HNCs.

Non-thermal plasma induces AKT degradation through turn-on the MUL1 E3 ligase in head and neck cancer.

Recent research on non-thermal plasma (NTP, an ionized gas) has identified it as a novel cancer therapeutic tool. However, the molecular mechanism remains unclear. In this study, we demonstrated NTP induced cell death of head and neck cancer (HNC) through the AKT ubiquitin-proteasome system. NTP increased the gene expression of mitochondrial E3 ubiquitin protein ligase 1 (MUL1), an E3 ligase for AKT, and NTP-induced HNC cell death was prevented by MUL1 siRNA. We also showed that MUL1 inhibited the level of AKT and p-AKT and MUL1 expression was increased by NTP-induced ROS. Furthermore, we optimized and manufactured a new type of NTP, a liquid type of NTP (LTP). In syngeneic and xenograft in vivo tumor models, LTP inhibited tumor progression by increasing the MUL1 level and reducing p-AKT levels, indicating that LTP also has an anti-cancer effect through the same mechanism as that of NTP. Taken together, our results suggest that NTP and LTP have great potential for HNC therapy.