Anti-cancer effects of plant-derived Micromonospora sp. M2 against A549 and MCF-7 cell lines.

The huge diversity of secondary bioactive metabolites, such as antibiotic and anticancer compounds produced by Micromonospora sp., makes it an attractive target for study. Here, we explored the anti-proliferative activities of Micromonospora sp. M2 extract (MBE) in relation to its pro-oxidative activities in A549 and MCF7 cell lines. Anti-proliferative effects were assessed by treating cells with MBE. We found that treatment with MBE decreased cell proliferation and increased intracellular reactive oxygen species, and that these observations were facilitated by the suppression of the PI3K-AKT pathway, alterations to the Bcl/Bad ratio, and increased caspase activity. These observations also demonstrated that MBE induced apoptotic cell death in cell lines. In addition, the phosphorylation of P38 and c-Jun N-terminal kinase (JNK) were upregulated following MBE treatment in both cell lines. Collectively, these results indicate that MBE acts as an anticancer agent via oxidative stress and JNK/mitogen-activated protein kinase pathway activation, enhancing apoptotic cell death in cell lines.

Centipedegrass extract enhances radiosensitivity in melanoma cells by inducing G2/M cell cycle phase arrest.

Melanoma is aggressive, highly metastatic, and potentially fatal. In the case of patients with advanced melanoma, it is difficult to expect a good prognosis, since this cancer has low sensitivity to chemotherapy and radiation therapy. The use of natural ingredients may enhance existing therapies. Centipedegrass extract (CGE) which contains phenolic structures and C-glycosyl flavones, has been shown to have anti-inflammatory effects and anti-cancer effects. The purpose of this study was to evaluate the radio sensitizing effects of CGE in combination with ionizing radiation (IR). Two melanoma cell lines were exposed to IR after treatment with CGE at concentrations that were not toxic alone. The effects of CGE + IR on cell survival, cell cycle, and apoptotic cell death were examined using MTT and Muse® Cell Analyzer, and fluorescence microscopy. Molecular signaling mechanisms were explored by western blots. Our findings showed that co-treatment of CGE + IR reduced the survival of melanoma cells more than IR alone. Also, cell cycle arrest in CGE-treated cells was enhanced and these cells became more radiosensitive. CGE + IR increased apoptotic cell death more than IR alone. Western blot results showed that the effect of CGE + IR involved MAPKs (ERK1/2, p38, and JNK) pathway. Our study suggests that CGE + IR treatment enhanced radio-sensitization and cell death of melanoma cells via cell cycle arrest and the MAPKs pathway.

Boehmite enhances hair follicle growth via stimulation of dermal papilla cells by upregulating ß-catenin signalling.

Hair growth, a complex process, has long been the subject of intense research. Recent developments in material technology have revealed boehmite as a new therapeutic modality for use in wound healing and scar reduction, indicating its beneficial effects. Nonetheless, the biological bases of the beneficial effects of boehmite remain unknown. We investigated the hair growth properties of boehmite in vitro and in vivo and observed dose-dependent proliferation of human dermal papilla cells (hDPCs) in vitro and hair regrowth in a mouse model. To investigate the effects of boehmite on the promotion of cell transition to the anagen phase, we evaluated hDPC viability, alkaline phosphatase (ALP) activity, protein expression and vascular endothelial growth factor (VEGF) secretion in vitro and assessed the anagen-promoting effects of boehmite via gross observation and histological analysis in a mouse model. Boehmite increased hDPC viability, ALP activity, AKT/GSK3ß/ß-catenin pathway activity, anagen-related gene expression and VEGF secretion; moreover, it accelerated hair regrowth in a catagen-anagen transition model via upregulation of ß-catenin signalling and follicular cell proliferation. Collectively, our results indicate that boehmite accelerates hair growth, partly via its effects on critical events in the active phase of the hair follicle cycle, including the promotion of the proliferation of hDPCs and their immediate progeny to the follicle base.

Delphinidin enhances radio-therapeutic effects via autophagy induction and JNK/MAPK pathway activation in non-small cell lung cancer.

Delphinidin is a major anthocyanidin compound found in various vegetables and fruits. It has anti-oxidant, anti-inflammatory, and various other biological activities. In this study we demonstrated the anti-cancer activity of delphinidin, which was related to autophagy, in radiation-exposed non-small cell lung cancer (NSCLC). Radiosensitising effects were assessed in vitro by treating cells with a subcytotoxic dose of delphinidin (5 µM) before exposure to γ-ionising radiation (IR). We found that treatment with delphinidin or IR induced NSCLC cell death in vitro; however the combination of delphinidin pre-treatment and IR was more effective than either agent alone, yielding a radiation enhancement ratio of 1.54 at the 50% lethal dose. Moreover, combined treatment with delphinidin and IR, enhanced apoptotic cell death, suppressed the mTOR pathway, and activated the JNK/MAPK pathway. Delphinidin inhibited the phosphorylation of PI3K, AKT, and mTOR, and increased the expression of autophagy-induced cell death associated-protein in radiation-exposed NSCLC cells. In addition, JNK phosphorylation was upregulated by delphinidin pre-treatment in radiation-exposed NSCLC cells. Collectively, these results show that delphinidin acts as a radiation-sensitizing agent through autophagy induction and JNK/MAPK pathway activation, thus enhancing apoptotic cell death in NSCLC cells.

Inhibition of melanogenesis by sodium 2-mercaptoethanesulfonate.

Sodium 2-mercaptoethanesulfonate (mesna) is a protective agent that is widely used in medicine because of its antioxidant effects. Recently, reactive oxygen species (ROS) were shown to increase pigmentation. Thus, ROS scavengers and inhibitors of ROS production may suppress melanogenesis. Forkhead box-O3a (FoxO3a) is an antimelanogenic factor that mediates ROS-induced skin pigmentation. In this study, we aimed to investigate the whitening effect of mesna and the signaling mechanism mediating this effect. Human melanoma (MNT-1) cells were used in this study. mRNA and protein expression were measured by real-time quantitative PCR and Western blotting analysis to track changes in FoxO3a-related signals induced by mesna. An immunofluorescence assay was performed to determine the nuclear translocation of FoxO3a. When MNT-1 melanoma cells were treated with mesna, melanin production and secretion decreased. These effects were accompanied by increases in FoxO3a activation and nuclear translocation, resulting in downregulation of four master genes of melanogenesis: MITF, TYR, TRP1, and TRP2. We found that mesna, an antioxidant and radical scavenger, suppresses melanin production and may therefore be a useful agent for the clinical treatment of hyperpigmentation disorders.

Antioxidant effect of human placenta hydrolysate against oxidative stress on muscle atrophy.

Sarcopenia, which refers to the muscle loss that accompanies aging, is a complex neuromuscular disorder with a clinically high prevalence and mortality. Despite many efforts to protect against muscle weakness and muscle atrophy, the incidence of sarcopenia and its related permanent disabilities continue to increase. In this study, we found that treatment with human placental hydrolysate (hPH) significantly increased the viability (approximately 15%) of H2 O2 -stimulated C2C12 cells. Additionally, while H2 O2 -stimulated cells showed irregular morphology, hPH treatment restored their morphology to that of cells cultured under normal conditions. We further showed that hPH treatment effectively inhibited H2 O2 -induced cell death. Reactive oxygen species (ROS) generation and Mstn expression induced by oxidative stress are closely associated with muscular dysfunction followed by atrophy. Exposure of C2C12 cells to H2 O2 induced abundant production of intracellular ROS, mitochondrial superoxide, and mitochondrial dysfunction as well as myostatin expression via nuclear factor-κB (NF-κB) signaling; these effects were attenuated by hPH. Additionally, hPH decreased mitochondria fission-related gene expression (Drp1 and BNIP3) and increased mitochondria biogenesis via the Sirt1/AMPK/PGC-1α pathway and autophagy regulation. In vivo studies revealed that hPH-mediated prevention of atrophy was achieved predominantly through regulation of myostatin and PGC-1α expression and autophagy. Taken together, our findings indicate that hPH is potentially protective against muscle atrophy and oxidative cell death.

Therapeutic potential of topically administered γ-AlOOH on 2,4-dinitrochlorobenzene-induced atopic dermatitis-like lesions in Balb/c mice.

Boehmite (γ-AlOOH) has a wide range of applications in a variety of industrial and biological fields. However, little is known about its potential roles in skin diseases. The current study investigated its effect on atopic dermatitis (AD). Following characterization, cytotoxicity, pro-inflammatory response and oxidative stress associated with boehmite were assessed, using TNF-α-induced keratinocytes and mast cells. In addition, therapeutic effects of boehmite, topically administered to Balb/c mice induced by 2,4-dinitrochlorobenzene (DNCB), were evaluated. Expression of cytokines (TLSP, IL-25 and IL-33) and the generation of ROS from keratinocytes induced by TNF-α were significantly inhibited by boehmite without affecting cell viability. MAPKs (ERK, JNK and p38) required for cytokine expression were suppressed by boehmite treatment. Up-regulation of cytokines (TSLP, IL-4, IL-5, IL-13, RANTES) in human mast cells treated with phorbol 12-myristate 13-acetate and calcium ionophore was also suppressed by boehmite. Boehmite improved the AD severity score, epidermal hyperplasia and transepidermal water loss in DNCB-induced AD-like lesions. Moreover, Th2-mediated cytokine expression, mast cell hyperplasia and destruction of the skin barrier were improved by boehmite treatment. Overall, we demonstrated that boehmite may potentially protect against AD.

Irradiation with 310 nm and 340 nm ultraviolet light-emitting-diodes can improve atopic dermatitis-like skin lesions in NC/Nga mice.

Ultraviolet (UV) light produces an immunomodulatory effect on the skin and is widely used for the treatment of chronic inflammatory skin diseases. UV light emitting diodes (UV-LEDs) are a new and promising source of UV radiation. However, their mechanism of action remains largely unknown. In this study, we tested the safety and effectiveness of UV-LED irradiation for the treatment of atopic dermatitis (AD) in an NC/Nga mouse model. Mice were divided into seven groups of eight mice each. Application of Dermatophagoides farinae (Df) extract ointment for four weeks induced AD-like skin lesions. Subsequently, the mice were exposed to UV-LEDs, narrow band UVB, or UVA irradiation three times per week. We assessed the immunosuppressive effects of 310 nm (50 mJ cm-2) and 340 nm (5 J cm-2) UV-LED irradiation. Histological analyses using hematoxylin-eosin, toluidine blue, and immunohistochemical staining were performed. In addition, the serum levels of IgE, inflammatory cytokines and chemokines were measured using enzyme-linked immunosorbent assays (ELISAs). UV-LED irradiation significantly alleviated AD-like skin symptoms, including edema, erythema, dryness, and itching, by modulating Th1 and Th2 responses, transepidermal water loss (TEWL), and scratching behavior in NC/Nga mice. These results suggest that UV-LEDs can improve the treatment of inflammatory skin diseases.

Fractional CO2 laser treatment for vaginal laxity: A preclinical study.

BACKGROUND AND OBJECTIVE: Various studies have investigated treatment for vaginal laxity with microablative fractional carbon dioxide CO2 laser in humans; however, this treatment has not yet been studied in an animal model. Herein, we evaluate the therapeutic effects of fractional CO2 laser for tissue remodeling of vaginal mucosa using a porcine model, with the aim of improving vaginal laxity. STUDY DESIGN/MATERIALS AND METHODS: The fractional CO2 laser enables minimally invasive and non-incisional procedures. By precisely controlling the laser energy pulses, energy is sent to the vaginal canal and the introitus area to induce thermal denaturation and contraction of collagen. We examined the effects of fractional CO2 laser on a porcine model via clinical observation and ultrasound measurement. Also, thermal lesions were histologically examined via hematoxylin-eosin staining, Masson's trichrome staining, and Elastica van Gieson staining and immunohistochemistry. RESULTS: The three treatment groups, which were determined according to the amount of laser-energy applied (60, 90, and 120 mJ), showed slight thermal denaturation in the vaginal mucosa, but no abnormal reactions, such as excessive hemorrhaging, vesicles, or erythema, were observed. Histologically, we also confirmed that the denatured lamina propria induced by fractional CO2 laser was dose-dependently increased after laser treatment. The treatment groups also showed an increase in collagen and elastic fibers due to neocollagenesis and angiogenesis, and the vaginal walls became firmer and tighter because of increased capillary and vessel formation. Also, use of the fractional CO2 laser increased HSP (heat shock protein) 70 and collagen type I synthesis. CONCLUSION: Our results show that microablative fractional CO2 laser can produce remodeling of the vaginal connective tissue without causing damage to surrounding tissue, and the process of mucosa remodeling while under wound dressings enables collagen to increase and the vaginal wall to become thick and tightened. Lasers Surg. Med. 50:940-947, 2018. © 2018 Wiley Periodicals, Inc.

Human umbilical cord blood mesenchymal stem cells engineered to overexpress growth factors accelerate outcomes in hair growth.

Human umbilical cord blood mesenchymal stem cells (hUCB-MSCs) are used in tissue repair and regeneration; however, the mechanisms involved are not well understood. We investigated the hair growth-promoting effects of hUCB-MSCs treatment to determine whether hUCB-MSCs enhance the promotion of hair growth. Furthermore, we attempted to identify the factors responsible for hair growth. The effects of hUCB-MSCs on hair growth were investigated in vivo, and hUCB-MSCs advanced anagen onset and hair follicle neogeneration. We found that hUCB-MSCs co-culture increased the viability and up-regulated hair induction-related proteins of human dermal papilla cells (hDPCs) in vitro. A growth factor antibody array revealed that secretory factors from hUCB-MSCs are related to hair growth. Insulin-like growth factor binding protein-1 (IGFBP-1) and vascular endothelial growth factor (VEGF) were increased in co-culture medium. Finally, we found that IGFBP-1, through the co-localization of an IGF-1 and IGFBP-1, had positive effects on cell viability; VEGF secretion; expression of alkaline phosphatase (ALP), CD133, and ß-catenin; and formation of hDPCs 3D spheroids. Taken together, these data suggest that hUCB-MSCs promote hair growth via a paracrine mechanism.

Targeting of sebaceous glands to treat acne by micro-insulated needles with radio frequency in a rabbit ear model.

BACKGROUND AND OBJECTIVES: Many studies have investigated the application of micro-insulated needles with radio frequency (RF) to treat acne in humans; however, the use of a micro-insulated needle RF applicator has not yet been studied in an animal model. The purpose of this study was to evaluate the effectiveness of a micro-insulated needle RF applicator in a rabbit ear acne (REA) model. STUDY DESIGN/MATERIALS AND METHODS: In this study, we investigated the effect of selectively destroying the sebaceous glands using a micro-insulated needle RF applicator on the formation of comedones induced by application of 50% oleic acid and intradermal injection of P. acnes in the orifices of the external auditory canals of rabbits. The effects of the micro-insulated needle RF applicator treatment were evaluated using regular digital photography in addition to 3D Primos imaging evaluation, Skin Visio Meter microscopic photography, and histologic analyses. RESULTS: Use of the micro-insulated needle RF applicator resulted in successful selective destruction of the sebaceous glands and attenuated TNF-alpha release in an REA model. The mechanisms by which micro-insulated needles with RF using 1 MHz exerts its effects may involve inhibition of comedone formation, triggering of the wound healing process, and destruction of the sebaceous glands and papules. CONCLUSION: The use of micro-insulated needles with RF applicators provides a safe and effective method for improving the appearance of symptoms in an REA model. The current in vivo study confirms that the micro-insulated needle RF applicator is selectively destroying the sebaceous glands. Lasers Surg. Med. 49:395-401, 2017. © 2016 Wiley Periodicals, Inc.

Protective Effects of Indole-3-Carbinol-Loaded Poly(lactic-co-glycolic acid) Nanoparticles Against Glutamate-Induced Neurotoxicity.

Indole-3-carbinol (I3C) has anti-oxidant and anti-inflammatory properties. Nonetheless, the potential of I3C to treat neurodegenerative diseases remains unclear because of its poor ability to penetrate the blood-brain barrier (BBB). Because polymer-based drug delivery systems stabilized by surfactants have been intensively utilized as a strategy to cross the blood-brain barrier, we prepared I3C-loaded poly(D,L-lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) that were stabilized by Tween 80 (T80) (I3C-PLGA-T80-NPs) and examined their neuroprotective potential in vitro. We prepared I3C-PLGA-T80-NPs with an oil-in-water (o/w) emulsion solvent evaporation technique and confirmed their successful synthesis with both transmission electron microscopy and Fourier transform-infrared spectroscopy. I3C-PLGA-T80-NPs were then used to treat PC12 neuronal cells injured by glutamate excitotoxicity (GE) and examined the resulting survival rates compared with PC12 cells treated with I3C only. The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay revealed higher survival rates in I3C-PLGA-T80-NPs-treated cells after GE injury compared with those treated with I3C only. Furthermore, I3C-PLGA-T80-NPs decreased the levels of reactive oxygen species (ROS) and apoptosis-related enzymes (Caspase-3 and -8) in GE-damaged neuronal cells. Taken together, I3C-PLGA-T80-NPs might possess neuroprotective effects against GE through ROS scavenging and subsequent apoptosis blockage.

In vivo study of newly developed albumin-conjugated urate oxidase for gout treatment.

BACKGROUND: Exogenously providing engineered Uox with enhanced half-life is one of the important urate-lowering treatments for gout. The potential of PAT101, a recombinant human albumin (rHA)-conjugated variant, was evaluated and compared as a novel gout treatment through various in vivo studies with PAT101 and competing drugs. METHODS: PAT101 was produced by site-specific conjugation of rHA and Aspergillus flavus Uox (AfUox-rHA) through clickable non-natural amino acid (frTet) and Inverse electron demand Diels-Alder (IEDDA) reaction. In vivo pharmacokinetics, efficacy tests and in vitro immunogenetic assay were performed after single or multiple doses of PAT101 and its competitors in BALB/c mice, transgenic (TG) mice, Sprague-Dawley (SD) rats, and non-human primate (NHP). RESULTS: The half-life of PAT101 in single-dose treated TG mice was more than doubled compared to pegloticase. In SD rats with 4 weeks of repeated administration of rasburicase, only 24% of Uox activity remained, whereas in PAT101, it was maintained by 86%. In the Uox KO model, the survival rate of PAT101 was comparable to that of pegloticase. In addition, human PBMC-based CD4+/CD8+ T-cell activation analysis demonstrated that PAT101 has a lower immune response compared to the original drug, rasburicase. CONCLUSION: All results suggest that this rHA-conjugated AfUox, PAT101, can be provided as a reliable source of Uox for gout treatment.

Transformation of nomifensine using ionizing radiation and exploration of its anticancer effects in MCF-7 cells.

Breast cancer is one of the most challenging diseases to treat in humans worldwide. There are several alternatives in treating this life-threatening disease; however, chemoresistance is probably the biggest obstacle to the treatment of breast cancer. It may be essential to develop a therapeutic candidate material with less reversible effects and high treatment efficiency to solve this problem. The present study applied an ionizing radiation approach employing nomifensine (NF) to transform its chemical characteristics and investigated its potential to kill human breast cancer cells (MCF-7). Irradiated (IR-) NF was analyzed using high-performance liquid chromatography. The findings showed that NF inhibited the proliferation of breast cancer cells and increased the rate of apoptosis. In addition, IR-NF induced the accumulation of cytosolic reactive oxygen species and enhanced mitochondrial aggregation. Additionally, mitogen-activated protein kinases (extracellular signal-regulated kinase 1/2, p38 and c-Jun NH 2-terminal kinase) were involved in damage signaling induced by IR-NF and IR-NF suppressed ß-catenin nuclear translocation. It is suggested that irradiation can be an effective method to maximize the efficacy of existing drugs and that IR-NF has the potential to be a drug candidate for treating patients with breast cancer.

The effects of centipedegrass extract on hair growth via promotion of anagen inductive activity.

To investigate the CGE on hair growth and to explore the mechanism that is involved in the acceleration of anagen induction, we investigated the effects of CGE studied on cell proliferation and molecular mechanism in human hair dermal papilla cells (hDPCs) and keratinocytes (HaCaT cells). Additionally, hair growth evaluation was carried out following topical treatment of the dorsal skin of telogen C57BL/6 mice with CGE for 14 days. As result, CGE increased cell viability and ALP activity in hDPCs. Moreover, CGE increased the expression of catenin beta 1 (CTNNB1), ALP, sex-determining region Y-box 2 (SOX2), insulin-like growth factor 1 (IGF1), and vascular endothelial growth factor A (VEGFA) genes in hDPCs. CGE increased the expression of proteins such as ALP, ß-catenin, and phosphorylation of glycogen synthase kinase 3ß (pGSK3ß), and protein kinase B (pAKT) in hDPCs. Furthermore, CGE induced the proliferation of HaCaT cells and up-regulated AKT-ERK-GSKß-ß-catenin signaling in HaCaT cells. Additionally, the anagen induction effects of CGE were confirmed on the telogen-anagen transition mice model. these findings demonstrated that CGE promoted the entering the growth phase of hair follicle via activation of ß-catenin signaling pathways in vivo. Thus, this study suggests that CGE might be a potential therapeutic reagent for hair growth.

A novel radiolytic rotenone derivative, rotenoisin A, displays potent anticarcinogenic activity in breast cancer cells.

Chemotherapy for cancer treatment has therapeutic limitations, such as drug resistance, excessive toxic effects and undesirable adverse effects. Therefore, efforts to improve the safety and efficacy of chemotherapeutic agents are essential. Ionizing radiation can improve physiological and pharmacological properties by transforming structural modifications of the drug. In this study, in order to reduce the adverse effects of rotenone and increase anticancer activity, a new radiolytic rotenone derivative called rotenoisin A was generated through radiolytic transformation. Our findings showed that rotenoisin A inhibited the proliferation of breast cancer cells and increased the rate of apoptosis, whereas it had no inhibitory effect on primary epidermal keratinocytes compared with rotenone. Moreover, rotenoisin A-induced DNA damage by increasing reactive oxygen species (ROS) accumulation. It was also confirmed not only to alter the composition ratio of mitochondrial proteins, but also to result in structural and functional changes. The anticancer effect and molecular signalling mechanisms of rotenoisin A were consistent with those of rotenone, as previously reported. Our study suggests that radiolytic transformation of highly toxic compounds may be an alternative strategy for maintaining anticancer effects and reducing the toxicity of the parent compound.

Radioprotective effects of centipedegrass extract on NIH-3T3 fibroblasts via anti-oxidative activity.

Centipedegrass originates from China and South America, and has been reported to contain several C-glycosyl flavones and phenolic compounds, including maysin and luteolin. The present study aimed to investigate the radioprotective activity of centipedegrass extract (CGE) in radiation exposed-fibroblasts and to assess the affected molecular pathway. The radioprotective effects of CGE were determined in NIH-3T3 cells using Cell Counting Kit-8 and morphological changes were observed. Reactive oxygen species (ROS) levels and the apoptotic profile of NIH-3T3 cells were also measured. The expression levels of B-cell lymphoma-2 (Bcl-2) family proteins [Bcl-2, Bcl-2 like protein 4 (Bax), Bcl-2-associated death promoter (Bad), caspase-3, poly(ADP-ribose) polymerase (PARP)], AKT and MAPK family proteins (ERK, p38 and JNK) were measured in vitro. The results demonstrated that when 3T3 fibroblasts pretreated with CGE were subjected to H2O2-induced cell damage, their viability was significantly decreased. Additionally, CGE pretreatment decreased ROS levels and the protein expression levels of cleaved PARP upon H2O2 treatment, indicating that CGE induced cytoprotective effects against H2O2-induced oxidative stress. Moreover, significant protective effects of CGE against intracellular ROS, induced upon exposure to ionizing radiation (IR), were observed. The protective effects of CGE pretreatment were also determined by morphological observation of NIH-3T3 cells following exposure to IR. CGE pretreatment increased the expression levels of anti-apoptotic signals (Bcl-2, p-BAD) and decreased the levels of pro-apoptotic signals (Bax, Bad), and led to cleavage of PARP and caspase-3 proteins. Additionally, in cells pretreated with CGE, the phosphorylation of AKT and ERK was increased and that of p38 and JNK was decreased compared with in cells subjected only to IR. These results indicated that CGE may act as a radioprotector due to its anti-oxidative activity, restoring cell homeostasis and redox balance in radiation-exposed fibroblast cells. Therefore, it could be suggested that CGE may be an effective candidate in the treatment of oxidative stress-related diseases and in radioprotection.

Regulation of Dual Activity of Ascorbate Peroxidase 1 From Arabidopsis thaliana by Conformational Changes and Posttranslational Modifications.

Ascorbate peroxidase (APX) is an important reactive oxygen species (ROS)-scavenging enzyme, which catalyzes the removal of hydrogen peroxide (H2O2) to prevent oxidative damage. The peroxidase activity of APX is regulated by posttranslational modifications (PTMs), such as S-nitrosylation, tyrosine nitration, and S-sulfhydration. In addition, it has been recently reported that APX functions as a molecular chaperone, protecting rice against heat stress. In this study, we attempted to identify the various functions of APX in Arabidopsis and the effects of PTMs on these functions. Cytosol type APX1 from Arabidopsis thaliana (AtAPX1) exists in multimeric forms ranging from dimeric to high-molecular-weight (HMW) complexes. Similar to the rice APX2, AtAPX1 plays a dual role behaving both as a regular peroxidase and a chaperone molecule. The dual activity of AtAPX1 was strongly related to its structural status. The main dimeric form of the AtAPX1 protein showed the highest peroxidase activity, whereas the HMW form exhibited the highest chaperone activity. Moreover, in vivo studies indicated that the structure of AtAPX1 was regulated by heat and salt stresses, with both involved in the association and dissociation of complexes, respectively. Additionally, we investigated the effects of S-nitrosylation, S-sulfhydration, and tyrosine nitration on the protein structure and functions using gel analysis and enzymatic activity assays. S-nitrosylation and S-sulfhydration positively regulated the peroxidase activity, whereas tyrosine nitration had a negative impact. However, no effects were observed on the chaperone function and the oligomeric status of AtAPX1. Our results will facilitate the understanding of the role and regulation of APX under abiotic stress and posttranslational modifications.

Protective effects of human umbilical cord blood­derived mesenchymal stem cells against dexamethasone­induced apoptotic cell death in hair follicles.

Alopecia is a common and distressing condition, and developing new therapeutic agents to prevent hair loss is important. Human umbilical cord blood­derived mesenchymal stem cells (hUCB­MSCs) have been studied intensively in regenerative medicine. However, the therapeutic potential of these cells against hair loss and hair organ damage remains unclear, and the effects of hUCB­MSC transplantation on hair loss require evaluation. The current study aimed to investigate the effects of hUCB­MSCs on hair regression in vivo and restoration of anagen conduction on hair growth in vitro. The effects of hUCB­MSCs were explored in mouse catagen induction models using a topical treatment of 0.1% dexamethasone to induce hair regression. Dexamethasone was also used to simulate a stress environment in vitro. The results demonstrated that hUCB­MSCs significantly prevented hair regression induced by dexamethasone topical stimulation in vivo. Additionally, hUCB­MSCs significantly increased the proliferation of human dermal papilla cells (hDPCs) and HaCaT cells, which are key constituent cells of the hair follicle. Stimulation of vascular endothelial growth factor secretion and decreased expression of DKK­1 by hUCB­MSCs were also observed in hDPCs. Restoration of cell viability by hUCB­MSCs suggested that these cells exerted a protective effect on glucocorticoid stress­associated hair loss. In addition, anti­apoptotic effects and regulation of the autophagic flux recovery were observed in HaCaT cells. The results of the present study indicated that hUCB­MSCs may have the capacity to protect hair follicular dermal papilla cells and keratinocytes, thus preventing hair loss. Additionally, the protective effects of hUCB­MSCs may be resistant to dysregulation of autophagy under harmful stress.

A hydroxyethyl derivative of chrysin exhibits anti-inflammatory activity in dendritic cells and protective effects against dextran sodium salt-induced colitis in mice.

Inflammatory bowel disease (IBD) is a chronic disease that occurs in the intestinal tract. Phyto-ingredients have been evaluated for their ability to protect against IBD because of their anti-inflammatory activities. In our previous study, we identified a novel derivative of chrysin (HE-chrysin) using irradiation technology, which exhibited stronger anti-cancer activity in human colorectal cancer cells than the original chrysin. Here, to determine whether HE-chrysin is a new therapeutic candidate for IBD, we investigated the anti-inflammatory effects of HE-chrysin on bone marrow-derived dendritic cells (BMDCs) and dextran sodium salt (DSS)-induced colitis in mice. HE-chrysin more effectively inhibited BMDC maturation compared to chrysin, as demonstrated by the decreased levels of pro-inflammatory cytokines, surface molecules, antigen-presenting ability, and T cell proliferation/activation in lipopolysaccharide-stimulated BMDCs. These anti-inflammatory effects of HE-chrysin were regulated by mitogen-activated protein kinases and nuclear factor-κB. Furthermore, oral administration of HE-chrysin attenuated DSS-induced colitis symptoms and clinical signs in the mouse model. The protective effects of HE-chrysin treatment against colitis were mediated by decreasing Th1- and Th17-type cytokine levels. These results indicate that HE-chrysin is attractive candidate for IBD therapy.