We observed that treatment with dimethyl α-ketoglutarate (DMK) increased the amount of intracellular α-ketoglutarate significantly more than that of α-ketoglutarate in HaCaT cells. DMK also increased the level of intracellular 4-hydroxyproline and promoted the production of collagen in HaCaT cells. In addition, DMK decreased the production of collagenase and elastase and downregulated the expression of selected matrix metalloproteinases (MMPs), such as MMP-1, MMP-9, MMP-10, and MMP-12, via transcriptional inhibition. The inhibition of MMPs by DMK was mediated by the suppression of the IL-1 signaling cascade, leading to the attenuation of ERK1/2 phosphorylation and AP-1 transactivation. Our study results illustrate that DMK, an alkylated derivative of α-ketoglutarate, increased the level of 4-hydroxyproline, promoted the production of collagen, and inhibited the expression of selected MMPs by affecting the IL-1 cascade and AP-1 transactivation in HaCaT cells. The results suggest that DMK might be useful as an anti-wrinkle ingredient.

Chaenomeles sinensis is known to inhibit the development and progression of many age-related diseases, but the underlying molecular mechanisms are largely unclear. In the present study, we observed that the ethanol extract of Chaenomeles sinensis scavenged 2,2’-diphenylpicrylhydrazyl and 2,2’-azinobis diammonium radicals in vitro. The ethanol extract of Chaenomeles sinensisactivated antioxidant response element-luciferase activity and induced expression of NRF2 target genes in HaCaT cells. The ethanol extract of Chaenomeles sinensis also suppressed LPS-induced expression of COX-2 and iNOS proteins, and mRNA expression of TNF-α and IL-2 in RAW264.7 cells. Finally, the ethanol extract of Chaenomeles sinensis significantly suppressed testosterone propionate-induced benign prostatic hyperplasia in mice. Together, our study provides the evidence that the ethanol extract of Chaenomeles sinensis inhibits the development of benign prostatic hyperplasia by exhibiting anti-oxidant and anti-inflammatory effects.

We attempted to examine anti-inflammatory and anti-oxidant effects of 4′-O-β-D-glucosyl-5-O-methylvisamminol (GOMV), the first epigenetic inhibitor of histone phosphorylation at Ser10. While GOMV did not affect the viability of murine macrophage RAW 264.7 cells, it significantly suppressed lipopolysaccharide (LPS)-induced generation of prostaglandin E₂ (PGE₂) and nitric oxide (NO) through transcriptional inhibition of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). GOMV also scavenged free radicals in vitro, increased NF-E2-related factor 2 (NRF2), and activated antioxidant response element (ARE), thereby resulting in the induction of phase II cytoprotective enzymes in human keratinocyte HaCaT cells. Finally, GOMV significantly protected HaCaT cells against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced oxidative intracellular damages. Together, our results illustrate that GOMV possesses anti-inflammatory and anti-oxidant activity.
Antioxidant Response Elements ; Antioxidants ; Cyclooxygenase 2 ; Epigenomics ; Free Radicals ; Histones ; Humans ; In Vitro Techniques ; Keratinocytes ; Macrophages ; NF-E2-Related Factor 2 ; Nitric Oxide ; Nitric Oxide Synthase Type II ; Phosphorylation ; RAW 264.7 Cells

5-fluorouracil (5-FU) is a chemotherapeutic agent commonly used for treatment of solid tumors, including colorectal cancer. However, chemoresistance against 5-fluorouracil (5-FU) often limits its success for chemotherapy and, therefore, finding out appropriate adjuvant(s) that might overcome chemoresistance against 5-FU bears a significant importance. In the present study, we have found that α-mangostin can sensitize 5-FU-resistant SNUC5/5-FUR colon cancer cells to apoptosis. Exposure of α-mangostin induced significant DNA damages and increased the intracellular 8-hydroxyguanosine (8-OH-G) and 4-hydroxynonenal (4-HNE) levels in SNUC5 and SNUC5/5-FUR cells. Western blot analysis illustrated that α-mangostin-induced apoptosis was mediated by the activation of the extrinsic and intrinsic pathways in SNUC5/5-FUR cells. In particular, we observed that Fas receptor (FasR) level was lower in SNUC5/5-FUR cells, compared with SNUC5 cells and that silencing FasR attenuated α-mangostin-mediated apoptosis in SNUC5/5-FUR cells. Together, our study illustrates that α-mangostin might be an efficient apoptosis sensitizer that can overcome chemoresistance against 5-FU by activating apoptosis pathway.
Antigens, CD95 ; Apoptosis* ; Blotting, Western ; Colon* ; Colonic Neoplasms* ; Colorectal Neoplasms ; DNA Damage ; Drug Therapy ; Fluorouracil

Keratinocytes are constantly exposed to extracellular insults, such as ultraviolet B, toxic chemicals and mechanical stress, all of which can facilitate the aging of keratinocytes via the generation of intracellular reactive oxygen species (ROS). Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that plays a critical role in protecting keratinocytes against oxidants and xenobiotics by binding to the antioxidant response element (ARE), a cis-acting element existing in the promoter of most phase II cytoprotective genes. In the present study, we have attempted to find novel ethanol extract(s) of indigenous plants of Jeju island, Korea that can activate the Nrf2/ARE-dependent gene expression in human keratinocyte HaCaT cells. As a result, we identified that ethanol extract of Cirsium japonicum var. ussuriense Kitamura (ECJUK) elicited strong stimulatory effect on the ARE-dependent gene expression. Supporting this observation, we found that ECJUK induced the expression of Nrf2, hemoxygenase-1, and NAD(P)H:quinone oxidoreductase-1 and this event was correlated with Akt1 phosphorylation. We also found that ECJUK increased the intracellular reduced glutathione level and suppressed 12-O-tetradecanoylphorbol acetate-induced 8-hydroxyguanosine formation without affecting the overall viability. Collectively, our results provide evidence that ECJUK can protect against oxidative stress-mediated damages through the activation of Nrf2/ARE-dependent phase II cytoprotective gene expression.
Aging ; Antioxidant Response Elements* ; Cirsium* ; DNA Damage* ; DNA* ; Ethanol* ; Gene Expression ; Glutathione ; Humans* ; Keratinocytes* ; Korea ; Oxidants ; Phosphorylation ; Reactive Oxygen Species ; Stress, Mechanical ; Transcription Factors ; Xenobiotics

BACKGROUND: Recent genome-wide sequencing studies have identified unexpected genetic alterations in cancer. In particular, missense mutations in isocitrate dehydrogenase-1 (IDH1) at arginine 132, mostly substituted into histidine (IDH1-R132H) were observed to frequently occur in glioma patients. METHODS: We have purified recombinant IDH1 and IDH1-R132H proteins and monitored their catalytic activities. In parallel experiments, we have attempted to find new selective IDH1-R132H chemical inhibitor(s) from a fragment-based chemical library. RESULTS: We have found that IDH1, but not IDH1-R132H, can catalyze the conversion of isocitrate into alpha-ketoglutarate (alpha-KG). In addition, we have observed that IDH1-R132H was more efficient than IDH1 in converting alpha-KG into (R)-2-hydroxyglutarate (R-2HG). Moreover, we have identified a new hit molecule, e.g., 2-(3-trifluoromethylphenyl)isothioazol-3(2H)-one as a new selective IDH1-R132H inhibitor. CONCLUSIONS: We have observed an underlying biochemical mechanism explaining how a heterozygous IDH1 mutation contributes to the generation of R-2HG and increases cellular histone H3 trimethylation levels. We have also identified a novel selective IDH1-R132H chemical hit molecule, e.g., 2-(3-trifluoromethylphenyl)isothioazol-3(2H)-one, which could be used for a future lead development against IDH1-R132H.
Arginine ; Glioma ; Histidine ; Histones ; Humans ; Mutation, Missense

Endoscopic submucosal dissection (ESD) is a widely accepted treatment for early gastric and esophageal cancer. Compared to endoscopic mucosal resection, ESD has the advantage of enabling en bloc removal of tumors regardless of their size. However, ESD can result in a large artificial ulcer, which may lead to a considerable deformity. Circumferential mucosal defects of more than three-fourths the esophageal circumference, long longitudinal mucosal defects (>30 mm), and lesions in the upper esophagus are significant risk factors for the development of post-ESD strictures of the esophagus. In the stomach, a circumferential mucosal defects more than three-fourths in extent and longitudinal mucosal defects >5 cm are risk factors of post-ESD stricture. If scheduled early, regular endoscopic balloon dilation is effective in controlling and preventing post-ESD stricture. Moreover, intralesional steroid injections or oral steroids can achieve remission of dysphagia or reduce the need for repeated endoscopic balloon dilation. However, further study is needed to improve the prevention of stricture formation.
Congenital Abnormalities ; Constriction, Pathologic* ; Deglutition Disorders ; Esophageal Neoplasms ; Esophagus ; Risk Factors ; Steroids ; Stomach ; Ulcer

Prostate cancer is the most frequently diagnosed cancer. Although prostate tumors respond to androgen ablation therapy at an early stage, they often acquire the potential of androgen-independent growth. Elevated transcriptional activity of androgen receptor (AR) and/or signal transducer and activator of transcription-3 (STAT3) contributes to the proliferation of prostate cancer cells. In the present study, we examined the effect of resveratrol, a phytoalexin present in grapes, on the reporter gene activity of AR and STAT3 in human prostate cancer (LNCaP-FGC) cells stimulated with interleukin-6 (IL-6) and/or dihydrotestosterone (DHT). Our study revealed that resveratrol suppressed the growth of LNCaP-FGC cells in a time- and concentration-dependent manner. Whereas the AR transcriptional activity was induced by treatment with either IL-6 or DHT, the STAT3 transcriptional activity was induced only by treatment with IL-6 but not with DHT. Resveratrol significantly attenuated IL-6-induced STAT3 transcriptional activity, and DHT- or IL-6-induced AR transcriptional activity. Treatment of cells with DHT plus IL-6 significantly increased the AR transcriptional activity as compared to DHT or IL-6 treatment alone and resveratrol markedly diminished DHT plus IL-6-induced AR transcriptional activity. Furthermore, the production of prostate-specific antigen (PSA) was decreased by resveratrol in the DHT-, IL-6- or DHT plus IL-6-treated LNCaP-FGC cells. Taken together, the inhibitory effects of resveratrol on IL-6- and/or DHT-induced AR transcriptional activity in LNCaP prostate cancer cells are partly mediated through the suppression of STAT3 reporter gene activity, suggesting that resveratrol may be a promising therapeutic choice for the treatment of prostate cancer.
Dihydrotestosterone ; Genes, Reporter ; Humans ; Interleukin-6 ; Prostate ; Prostate-Specific Antigen ; Prostatic Neoplasms* ; Receptors, Androgen ; Transducers ; Vitis

A number of naturally-occurring or synthetic chemicals have been reported to exhibit prostate chemopreventive effects. Synthetic 5alpha-reductase (5-AR) inhibitors, e.g. finasteride and durasteride, gained special interests as possible prostate chemopreventive agents. Indeed, two large-scale epidemiological studies have demonstrated that finasteride or durasteride significantly reduced the incidence of prostate cancer formation in men. However, these studies have raised an unexpected concern; finasteride and durasteride increased the occurrence of aggressive prostate tumor formation. In the present study, we have observed that treatment of finasteride did not affect the growth of androgen-refractory PC-3 prostate cancer cells. Finasteride also failed to induce apoptosis or affect the expression of proto-oncogenes in PC-3 cells. Interestingly, we found that treatment of finasteride induced the expression of Nrf2 and HO-1 proteins in PC-3 cells. In particular, basal level of Nrf2 protein was higher in androgen-refractory prostate cancer cells, e.g. DU-145 and PC-3 cells, compared with androgen-responsive prostate cancer cells, e.g. LNCaP cells. Also, treatment of finasteride resulted in a selective induction of Nrf2 protein in DU-145 and PC-3 cells, but not in LNCaP cells. In view of the fact that upregulation of Nrf2-mediated phase II cytoprotective enzymes contribute to attenuating tumor promotion in normal cells, but, on the other hand, confers a selective advantage for cancer cells to proliferate and survive against chemical carcinogenesis and other forms of toxicity, we propose that finasteride-mediated induction of Nrf2 protein might be responsible, at least in part, for an increased risk of high-grade prostate tumor formation in men.
Apoptosis ; Carcinogenesis ; Chemoprevention ; Finasteride* ; Hand ; Humans ; Incidence ; Male ; Prostate* ; Prostatic Neoplasms ; Proto-Oncogenes ; Up-Regulation

Fucoxanthin is an important carotenoid derived from edible brown seaweeds and is used in indigenous herbal medicines. The aim of the present study was to examine the cytoprotective effects of fucoxanthin against hydrogen peroxide-induced cell damage. Fucoxanthin decreased the level of intracellular reactive oxygen species, as assessed by fluorescence spectrometry performed after staining cultured human HaCaT keratinocytes with 2',7'-dichlorodihydrofl uorescein diacetate. In addition, electron spin resonance spectrometry showed that fucoxanthin scavenged hydroxyl radical generated by the Fenton reaction in a cell-free system. Fucoxanthin also inhibited comet tail formation and phospho-histone H2A.X expression, suggesting that it prevents hydrogen peroxide-induced cellular DNA damage. Furthermore, the compound reduced the number of apoptotic bodies stained with Hoechst 33342, indicating that it protected keratinocytes against hydrogen peroxide-induced apoptotic cell death. Finally, fucoxanthin prevented the loss of mitochondrial membrane potential. These protective actions were accompanied by the down-regulation of apoptosis-promoting mediators (i.e., B-cell lymphoma-2-associated x protein, caspase-9, and caspase-3) and the up-regulation of an apoptosis inhibitor (B-cell lymphoma-2). Taken together, the results of this study suggest that fucoxanthin defends keratinocytes against oxidative damage by scavenging ROS and inhibiting apoptosis.
Apoptosis* ; B-Lymphocytes ; Caspase 9 ; Cell Death ; Cell-Free System ; DNA Damage ; Down-Regulation ; Electron Spin Resonance Spectroscopy ; Free Radicals* ; Humans* ; Hydrogen ; Hydroxyl Radical ; Keratinocytes* ; Membrane Potential, Mitochondrial ; Oxidative Stress* ; Reactive Oxygen Species ; Spectrometry, Fluorescence ; Spectrum Analysis ; Up-Regulation