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1.
Biomol Ther (Seoul) ; 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34607978

RESUMO

Resistance to chemotherapeutic drugs is a significant problem in the treatment of colorectal cancer, resulting in low response rates and decreased survival. Recent studies have shown that shikonin, a naphthoquinone derivative, promotes apoptosis in colon cancer cells and cisplatin-resistant ovarian cells, raising the possibility that this compound may be effective in drug-resistant colorectal cancer. The aim of this study was to characterize the molecular mechanisms underpinning shikonin-induced apoptosis, with a focus on endoplasmic reticulum (ER) stress, in a 5-fluorouracil-resistant colorectal cancer cell line, SNU-C5/5-FUR. Our results showed that shikonin significantly increased the proportion of sub-G1 cells and DNA fragmentation and that shikonin-induced apoptosis is mediated by mitochondrial Ca2+ accumulation. Shikonin treatment also increased the expression of ER-related proteins, such as glucose regulatory protein 78 (GRP78), phospho-protein kinase RNA-like ER kinase (PERK), phospho-eukaryotic initiation factor 2 (eIF2α), phospho-phosphoinositol-requiring protein-1 (IRE1), spliced X-box-binding protein-1 (XBP-1), cleaved caspase-12, and C/EBP-homologous protein (CHOP). In addition, siRNA-mediated knockdown of CHOP attenuated shikonininduced apoptosis, as did the ER stress inhibitor TUDCA. These data suggest that ER stress is a key factor mediating the cytotoxic effect of shikonin in SNU-C5/5-FUR cells. Our findings provide an evidence for a mechanism in which ER stress leads to apoptosis in shikonin-treated SNU-C5/5-FUR cells. Our study provides evidence to support further investigations on shikonin as a therapeutic option for 5-fluorouracil-resistant colorectal cancer.

2.
Pharmaceutics ; 13(9)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34575516

RESUMO

Air pollutants, especially ambient fine particulate matter2.5, may contribute to various ocular surface disorders, including dry eye disease, keratitis and conjunctivitis. A natural polyamine spermidine has a protective effect on the retina and optic nerve; however, no study has been conducted on the application of spermidine in particulate matter2.5-induced dry eye disease. In the present study, we investigated the effect of spermidine eye drops in topically exposed particulate matter2.5-induced dry eye models of Sprague-Dawley rats, by hematological, biochemical and histological evaluation. Spermidine eye drops attenuated the particulate matter2.5 exposure-induced reduction of tear secretion and corneal epithelial damage. Furthermore, spermidine protected against conjunctival goblet cell loss and retinal ganglion cell loss induced by particulate matter2.5. Additionally, spermidine markedly prevented particulate matter2.5-induced infiltration of cluster of differentiation3+ and cluster of differentiation4+ T lymphocytes and F4/80+ macrophages on lacrimal gland. Moreover, over expression of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-6 and interleukin-17 in the lacrimal gland and cornea. Meanwhile, the levels of serum total cholesterol and low-density lipoprotein cholesterol were markedly increased by topical exposure to particulate matter2.5, but this change in the lipid profile was decreased by spermidine. Taken together, spermidine may have protective effects against particulate matter2.5-induced dry eye symptoms via stabilization of the tear film and suppression of inflammation and may in part contribute to improving retinal function and lipid metabolism disorder.

3.
Biomol Ther (Seoul) ; 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34321365

RESUMO

Radiation resistance represents an imperative obstacle in the treatment of patients with colorectal cancer, which remains difficult to overcome. Here, we explored the anti-proliferative and migration-inhibiting properties of the natural product shikonin on a radiation- resistant human colon carcinoma cell line (SNU-C5RR). Shikonin reduced the viability of these cells in a dose-dependent manner; 38 µM of shikonin was determined as the half-maximal inhibitory concentration. Shikonin induced apoptotic cell death, as demonstrated by increased apoptotic body formation and the number of TUNEL-positive cells. Moreover, shikonin enhanced mitochondrial membrane depolarization and Bax expression and also decreased Bcl-2 expression with translocation of cytochrome c from mitochondria into the cytosol. In addition, shikonin activated mitogen-activated protein kinases, and their specific inhibitors reduced the cytotoxic effects of shikonin. Additionally, shikonin decreased the migration of SNU-C5RR cells via the upregulation of E-cadherin and downregulation of N-cadherin. Taken together, these results suggest that shikonin induces mitochondria-mediated apoptosis and attenuates epithelial-mesenchymal transition in SNU-C5RR cells.

4.
Biomol Ther (Seoul) ; 29(6): 685-696, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33820881

RESUMO

In this study, we investigated the inhibitory effect of 5-aminolevulinic acid (ALA), a heme precursor, on inflammatory and oxidative stress activated by lipopolysaccharide (LPS) in RAW 264.7 macrophages by estimating nitric oxide (NO), prostaglandin E2 (PGE2), cytokines, and reactive oxygen species (ROS). We also evaluated the molecular mechanisms through analysis of the expression of their regulatory genes, and further evaluated the anti-inflammatory and antioxidant efficacy of ALA against LPS in the zebrafish model. Our results indicated that ALA treatment significantly attenuated the LPS-induced release of pro-inflammatory mediators including NO and PGE2, which was associated with decreased inducible NO synthase and cyclooxygenase-2 expression. ALA also inhibited the LPS-induced expression of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6, reducing their extracellular secretion. Additionally, ALA abolished ROS generation, improved the mitochondrial mass, and enhanced the expression of heme oxygenase-1 (HO-1) and the activation of nuclear translocation of nuclear factor-E2-related factor 2 (Nrf2) in LPS-stimulated RAW 264.7 macrophages. However, zinc protoporphyrin, a specific inhibitor of HO-1, reversed the ALA-mediated inhibition of pro-inflammatory cytokines production and activation of mitochondrial function in LPS-treated RAW 264.7 macrophages. Furthermore, ALA significantly abolished the expression of LPS-induced pro-inflammatory mediators and cytokines, and showed strong protective effects against NO and ROS production in zebrafish larvae. In conclusion, our findings suggest that ALA exerts LPS-induced anti-inflammatory and antioxidant effects by upregulating the Nrf2/HO-1 signaling pathway, and that ALA can be a potential functional agent to prevent inflammatory and oxidative damage.

5.
Biomol Ther (Seoul) ; 29(2): 211-219, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33518533

RESUMO

Alopecia is a distressing condition caused by the dysregulation of anagen, catagen, and telogen in the hair cycle. Dermal papilla cells (DPCs) regulate the hair cycle and play important roles in hair growth and regeneration. Myristoleic acid (MA) increases Wnt reporter activity in DPCs. However, the action mechanisms of MA on the stimulation of anagen signaling in DPCs is not known. In this study, we evaluated the effects of MA on anagen-activating signaling pathways in DPCs. MA significantly increased DPC proliferation and stimulated the G2/M phase, accompanied by increasing cyclin A, Cdc2, and cyclin B1. To elucidate the mechanism by which MA promotes DPC proliferation, we evaluated the effect of MA on autophagy and intracellular pathways. MA induced autophagosome formation by decreasing the levels of the phospho-mammalian target of rapamycin (phospho-mTOR) and increasing autophagy-related 7 (Atg7) and microtubule-associated protein 1A/1B-light chain 3II (LC3II). MA also increased the phosphorylation levels of Wnt/ß-catenin proteins, such as GSK3ß (Ser9) and ß-catenin (Ser552 and Ser675). Treatment with XAV939, an inhibitor of the Wnt/ß-catenin pathway, attenuated the MA-induced increase in ß-catenin nuclear translocation. Moreover, XAV939 reduced MA-induced effects on cell cycle progression, autophagy, and DPC proliferation. On the other hand, MA increased the levels of phospho (Thr202/Tyr204)-extracellular signal regulated kinases (ERK). MA-induced ERK phosphorylation led to changes in the expression levels of Cdc2, Atg7 and LC3II, as well as DPC proliferation. Our results suggest that MA promotes anagen signaling via autophagy and cell cycle progression by activating the Wnt/ß-catenin and ERK pathways in DPCs.

6.
Antioxidants (Basel) ; 10(2)2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33498524

RESUMO

Urban particulate matter (UPM) is recognized as a grave public health problem worldwide. Although a few studies have linked UPM to ocular surface diseases, few studies have reported on retinal dysfunction. Thus, the aim of the present study was to evaluate the influence of UPM on the retina and identify the main mechanism of UPM toxicity. In this study, we found that UPM significantly induced cytotoxicity with morphological changes in ARPE-19 human retinal pigment epithelial (RPE) cells and increased necrosis and autophagy but not apoptosis. Furthermore, UPM significantly increased G2/M arrest and simultaneously induced alterations in cell cycle regulators. In addition, DNA damage and mitochondrial dysfunction were remarkably enhanced by UPM. However, the pretreatment with the potent reactive oxygen species (ROS) scavenger N-acetyl-L-cysteine (NAC) effectively suppressed UPM-mediated cytotoxicity, necrosis, autophagy, and cell cycle arrest. Moreover, NAC markedly restored UPM-induced DNA damage and mitochondrial dysfunction. Meanwhile, UPM increased the expression of mitophagy-regulated proteins, but NAC had no effect on mitophagy. Taken together, although further studies are needed to identify the role of mitophagy in UPM-induced RPE injury, the present study provides the first evidence that ROS-mediated cellular damage through necrosis and autophagy is one of the mechanisms of UPM-induced retinal disorders.

7.
Biomol Ther (Seoul) ; 29(1): 90-97, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32587122

RESUMO

Ultraviolet B (UVB) radiation causes DNA base modifications. One of these changes leads to the generation of 8-oxoguanine (8- oxoG) due to oxidative stress. In human skin, this modification may induce sunburn, inflammation, and aging and may ultimately result in cancer. We investigated whether phloroglucinol (1,3,5-trihydroxybenzene), by enhancing the expression and activity of 8-oxoG DNA glycosylase 1 (Ogg1), had an effect on the capacity of UVB-exposed human HaCaT keratinocytes to repair oxidative DNA damage. Here, the effects of phloroglucinol were investigated using a luciferase activity assay, reverse transcription-polymerase chain reactions, western blot analysis, and a chromatin immunoprecipitation assay. Phloroglucinol restored Ogg1 activity and decreased the formation of 8-oxoG in UVB-exposed cells. Moreover, phloroglucinol increased Ogg1 transcription and protein expression, counteracting the UVB-induced reduction in Ogg1 levels. Phloroglucinol also enhanced the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) as well as Nrf2 binding to an antioxidant response element located in the Ogg1 gene promoter. UVB exposure inhibited the phosphorylation of protein kinase B (PKB or Akt) and extracellular signal-regulated kinase (Erk), two major enzymes involved in cell protection against oxidative stress, regulating the activity of Nrf2. Akt and Erk phosphorylation was restored by phloroglucinol in the UVB-exposed keratinocytes. These results indicated that phloroglucinol attenuated UVB-induced 8-oxoG formation in keratinocytes via an Akt/Erk-dependent, Nrf2/Ogg1-mediated signaling pathway.

8.
Genes Genomics ; 43(1): 17-31, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33237503

RESUMO

BACKGROUND: Coptisine is a natural alkaloid compound and is known to have multiple beneficial effects including antioxidant activity. However, whether it can protect lung fibroblasts from oxidative damage has not been studied yet. OBJECTIVES: To investigate the potential inhibitory effect of coptisine against oxidative stress in V79-4 lung fibroblast cells. METHODS: V79-4 cells were treated with H2O2 (1 mM) in the presence or absence of coptisine (50 µg/ml), N-acetyl cysteine (NAC, 10 mM) or zinc protoporphyrin IX (ZnPP, 10 µM) for the indicated times. The alleviating effects of coptisine on cytotoxicity, cell cycle arrest, apoptosis, reactive oxygen species (ROS) production, DNA damage, mitochondrial dynamics, and inhibition of ATP production against H2O2 were investigated. Western blot analysis was used to analyze the expression levels of specific proteins. RESULTS: Coptisine inhibited H2O2-induced cytotoxicity and DNA damage by blocking abnormal ROS generation. H2O2 treatment caused cell cycle arrest at the G2/M phase accompanied by increased expression of cyclin-dependent kinase (Cdk) inhibitor p21WAF1/CIP1 and decreased expression of cyclin B1 and cyclin A. However, these effects were attenuated in the presence of coptisine or NAC. Coptisine also prevented apoptosis by decreasing the rate of Bax/Bcl-2 expression in H2O2-stimulated cells and suppressing the loss of mitochondrial membrane potential and the cytosolic release of cytochrome c. In addition, the activation of nuclear factor-erythroid-2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) was markedly promoted by coptisine in the presence of H2O2. However, zinc protoporphyrin IX, a potent inhibitor of HO-1, attenuated the ROS scavenging and anti-apoptotic effects of coptisine. CONCLUSIONS: Based on current data, we suggest that coptisine can be used as a potential treatment for oxidative stress-related lung disease.


Assuntos
Antioxidantes/farmacologia , Berberina/análogos & derivados , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Animais , Berberina/farmacologia , Linhagem Celular , Cricetinae , Cricetulus , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Peróxido de Hidrogênio/toxicidade , Fator 2 Relacionado a NF-E2/genética
9.
Redox Biol ; 37: 101698, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32863235

RESUMO

We have previously shown that non-thermal dielectric-barrier discharge (DBD) plasma induces the generation of reactive oxygen species (ROS) in cells; however, the underlying mechanism has not been elucidated. This study aimed to identify the mechanisms through which DBD plasma induces the expression of NADPH oxidase (NOX) family members by epigenetic modification in human keratinocytes (HaCaT). Cell exposure to DBD plasma in 10% oxygen and 90% argon resulted in the generation of ROS, triggering oxidative stress that manifested in various forms, including lipid membrane peroxidation, DNA base modification, and protein carbonylation. DBD plasma upregulated the expression of NOX1, NOX5, and DUOX2 at the mRNA and protein levels; and siRNAs targeting NOX1, NOX5, and DUOX2 attenuated the generation of DBD plasma-induced ROS. DBD plasma upregulated the transcriptional activators TET1, MLL1, and HAT1 and downregulated the transcriptional repressors DNMT1, EZH2, and HDAC1. Additionally, DBD plasma increased the binding of transcriptional activators and decreased the binding of transcriptional repressors to the DUOX2 promoter. Methyl-specific polymerase chain reaction and bisulfite sequencing indicated that DBD plasma decreased methylation at the DUOX2 promoter. These results suggest that DBD plasma induces ROS generation by enhancing the expression of the NOX system through epigenetic DNA and histone modifications.


Assuntos
Queratinócitos , NADPH Oxidases , Humanos , Oxigenases de Função Mista , NADPH Oxidase 1/genética , NADPH Oxidase 4/genética , NADPH Oxidase 5 , NADPH Oxidases/genética , Oxirredução , Estresse Oxidativo , Proteínas Proto-Oncogênicas , Espécies Reativas de Oxigênio
10.
Biochem Biophys Res Commun ; 529(3): 635-641, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32736685

RESUMO

Keratinocyte hyperproliferation is an essential link in skin cancer pathogenesis. Peroxiredoxin I (Prx I) is known to regulate cancer cell proliferation, differentiation, and apoptosis, but its role in skin cancer remains unclear. This study aimed to elucidate the role and mechanism of Prx I in skin cancer pathogenesis. Dimethylbenz[a]anthracene (DMBA) and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) were used to create a skin tumor model of the initiation/promotion stage of cancer. The role of Prx I in H2O2-induced keratinocyte apoptosis was also investigated. After DMBA/TPA treatment, Prx I deficiency was significantly associated with less skin tumors, lower Bcl-2 expression, and higher p-p38 and cleaved caspase-3 expressions in Prx I knockout tumors than in wild-type controls. H2O2 stimulation caused more cellular apoptosis in Prx I knockdown HaCaT cells than in normal HaCaT cells. The signaling study revealed that Bcl-2, p-p38, and cleaved caspase-3 expressions were consistent with the results in the tumors. In conclusion, the deletion of Prx I triggered the DMBA/TPA-induced skin tumor formation in vivo and in vitro by regulating the reactive oxygen species (ROS)-p38 mitogen-activated protein kinase (MAPK) pathway. These findings provide a theoretical basis for treating skin cancer.


Assuntos
Apoptose/genética , Queratinócitos/metabolismo , Peroxirredoxinas/genética , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Cutâneas/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Células HEK293 , Humanos , Peróxido de Hidrogênio/farmacologia , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Camundongos da Linhagem 129 , Camundongos Knockout , Oxidantes/farmacologia , Peroxirredoxinas/deficiência , Interferência de RNA , Transdução de Sinais , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
11.
Biomol Ther (Seoul) ; 28(5): 443-455, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32856616

RESUMO

The thioredoxin (Trx) system plays critical roles in regulating intracellular redox levels and defending organisms against oxidative stress. Recent studies indicated that Trx reductase (TrxR) was overexpressed in various types of human cancer cells indicating that the Trx-TrxR system may be a potential target for anti-cancer drug development. This study investigated the synergistic effect of auranofin, a TrxR-specific inhibitor, on sulforaphane-mediated apoptotic cell death using Hep3B cells. The results showed that sulforaphane significantly enhanced auranofin-induced apoptosis by inhibiting TrxR activity and cell proliferation compared to either single treatment. The synergistic effect of sulforaphane and auranofin on apoptosis was evidenced by an increased annexin-V-positive cells and Sub-G1 cells. The induction of apoptosis by the combined treatment caused the loss of mitochondrial membrane potential (ΔΨm) and upregulation of Bax. In addition, the proteolytic activities of caspases (-3, -8, and -9) and the degradation of poly (ADP-ribose) polymerase, a substrate protein of activated caspase-3, were also higher in the combined treatment. Moreover, combined treatment induced excessive generation of reactive oxygen species (ROS). However, treatment with N-acetyl-L-cysteine, a ROS scavenger, reduced combined treatment-induced ROS production and apoptosis. Thereby, these results deduce that ROS played a pivotal role in apoptosis induced by auranofin and sulforaphane. Furthermore, apoptosis induced by auranofin and sulforaphane was significantly increased through inhibition of the phosphoinositide 3-kinase (PI3K)/Akt pathway. Taken together, the present study demonstrated that down-regulation of TrxR activity contributed to the synergistic effect of auranofin and sulforaphane on apoptosis through ROS production and inhibition of PI3K/Akt signaling pathway.

12.
Int J Mol Sci ; 21(12)2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604799

RESUMO

The hair follicle goes through repetitive cycles including anagen, catagen, and telogen. The interaction of dermal papilla cells (DPCs) and keratinocytes regulates the hair cycle and hair growth. Humanin was discovered in the surviving brain cells of patients with Alzheimer's disease. HNG, a humanin analogue, activates cell growth, proliferation, and cell cycle progression, and it protects cells from apoptosis. This study was performed to investigate the promoting effect and action mechanisms of HNG on hair growth. HNG significantly increased DPC proliferation. HNG significantly increased hair shaft elongation in vibrissa hair follicle organ culture. In vivo experiment showed that HNG prolonged anagen duration and inhibited hair follicle cell apoptosis, indicating that HNG inhibited the transition from the anagen to catagen phase mice. Furthermore, HNG activated extracellular signal-regulated kinase (Erk)1/2, Akt, and signal transducer and activator of transcription (Stat3) within minutes and up-regulated vascular endothelial growth factor (VEGF) levels on DPCs. This means that HNG could induce the anagen phase longer by up-regulating VEGF, which is a Stat3 target gene and one of the anagen maintenance factors. HNG stimulated the anagen phase longer with VEGF up-regulation, and it prevented apoptosis by activating Erk1/2, Akt, and Stat3 signaling.


Assuntos
Derme/crescimento & desenvolvimento , Folículo Piloso/crescimento & desenvolvimento , Cabelo/crescimento & desenvolvimento , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Animais , Apoptose , Ciclo Celular , Proliferação de Células , Células Cultivadas , Derme/efeitos dos fármacos , Derme/metabolismo , Feminino , Cabelo/efeitos dos fármacos , Cabelo/metabolismo , Folículo Piloso/efeitos dos fármacos , Folículo Piloso/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Wistar , Fenômenos Fisiológicos da Pele
13.
Arch Biochem Biophys ; 691: 108512, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32712291

RESUMO

Hemistepsin A, a sesquiterpene lactone compound isolated from Hemistepta lyrata, has been identified a variety of pharmacological actions including anti-hepatotoxic, anti-inflammatory and anti-cancer activities. Nevertheless, the antioxidant effects of hemistepsin A and the underlying mechanisms have not been investigated properly. Therefore, in the present study, we investigated the protective effect of hemistepsin A against oxidative stress in HaCaT human keratinocytes. The results demonstrated that hemistepsin A suppressed 500 µM hydrogen peroxide (H2O2)-induced cytotoxicity and DNA damage by blocking ROS accumulation. 10 µM Hemistepsin A also prevented apoptosis by preventing the mitochondrial dysfunction and the cytosolic release of cytochrome c, reducing the rate of Bax/Bcl-2 expression, and decreasing the activation of caspase-9 and caspase-3, suggesting that hemistepsin A protected cells from H2O2-induced mitochondria-mediated apoptosis. In addition, hemistepsin A markedly promoted the activation of nuclear factor-erythroid-2-related factor 2 (Nrf2), which was associated with the enhanced expression and activity of heme oxygenase-1 (HO-1) in the presence of 500 µM H2O2. However, inhibiting the expression of HO-1 by artificially blocking the expression of Nrf2 or HO-1 using siRNA significantly eliminated the protective effect of hemistepsin A, indicating that hemistepsin A activates the Nrf2/HO-1 signaling pathway in HaCaT cells to protect against oxidative stress. Therefore, these results suggest that hemistepsin A may be useful as a potential therapeutic agent against various oxidative stress-related skin diseases.


Assuntos
Antioxidantes/farmacologia , Peróxido de Hidrogênio/toxicidade , Queratinócitos/efeitos dos fármacos , Lactonas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Sesquiterpenos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo
14.
Anticancer Res ; 40(7): 3819-3830, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32620621

RESUMO

BACKGROUND: Picrasma quassioides (PQ) is a traditional Asian herbal medicine with anti-tumor properties that can inhibit the viability of HepG2 liver cancer cells. H-Ras is often mutated in liver cancer, however, the effect of PQ treatment on H-Ras mutated liver cancer is unclear. This study aimed to investigate the role of PQ on ROS accumulation and mitochondrial dysfunction in H-ras mutated HepG2 (HepG2G12V) cells. MATERIALS AND METHODS: PQ ethanol extract-induced HepG2G12V apoptosis was analyzed by the MTT assay, fluorescence microscopy, flow cytometry and western blotting. RESULTS: PQ treatment affected cell migration and colony formation in HepG2G12V cells. Cleaved-caspase-3, cleaved-caspase-9 and BCL2 associated agonist of cell death (BAD) expression levels were increased, while the levels of B-cell lymphoma-extra large (Bcl-xL) were decreased with PQ treatment. PQ treatment led to a reduction of H-Ras expression levels in liver cancer cells, thus reducing their abnormal proliferation. Furthermore, it led to increased expression levels of Peroxiredoxin VI, which regulates the redox signal in cells. CONCLUSION: Taken together these results provide a new functional significance for the role of PQ in treating HepG2G12V liver cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Mitocôndrias Hepáticas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Genes ras , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Picrasma/química , Proteínas Proto-Oncogênicas p21(ras)/biossíntese
15.
Anticancer Res ; 40(8): 4491-4504, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32727779

RESUMO

BACKGROUND: Peroxiredoxin II (PRDX2) performs unique roles in cells. It can reduce peroxides through cysteine residues, and helps prevent the effects of oxidative stress on cells. It is closely related to the occurrence and development of various diseases, especially alcoholic liver injury and even liver cancer. The metabolism of alcohol in hepatocytes leads to the increase in the levels of reactive oxygen species (ROS), oxidative stress, injury, and apoptosis. Therefore, this study focused on the investigating the protection conferred by PRDX2 against alcohol-induced apoptosis of hepatocytes. MATERIALS AND METHODS: PRDX2 inhibition of alcohol-induced apoptosis in L02 hepatocytes was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, fluorescence microscopy, flow cytometry, western blotting and hematoxylin and eosin staining. RESULTS: The results showed that the levels of reactive oxygen species, protein kinase B, ß-catenin, B-cell lymphoma-2 (BCL2), BCL-XL, BCL2-associated X, cleaved caspase-3, and cleaved poly (ADP-ribose) polymerase in PRDX2-silenced cells were increased significantly after the treatment of cells with ethanol. Similar results were obtained in an in vivo Prdx2-knockout mouse model of alcoholic liver injury. Therefore, PRDX2 may regulate the phosphorylation of the AKT signal protein by eliminating reactive oxygen species from cells, and it inhibits the downstream mitochondria-dependent apoptosis pathway, and, thereby, the apoptosis of cells. CONCLUSION: Thus, PRDX2 may be a potential molecular target for the prevention and treatment of alcoholic liver injury.


Assuntos
Etanol/efeitos adversos , Hepatócitos/citologia , Peroxirredoxinas/genética , Transdução de Sinais , Apoptose , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fosforilação/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , beta Catenina/metabolismo
16.
Biomol Ther (Seoul) ; 28(4): 354-360, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32394669

RESUMO

The hair cycle (anagen, catagen, and telogen) is regulated by the interaction between mesenchymal cells and epithelial cells in the hair follicles. The proliferation of dermal papilla cells (DPCs), mesenchymal-derived fibroblasts, has emerged as a target for the regulation of the hair cycle. Here, we show that vanillic acid, a phenolic acid from wheat bran, promotes the proliferation of DPCs via a PI3K/Akt/Wnt/ß-catenin dependent mechanism. Vanillic acid promoted the proliferation of DPCs, accompanied by increased levels of cell-cycle proteins cyclin D1, CDK6, and Cdc2 p34. Vanillic acid also increased the levels of phospho(ser473)- Akt, phospho(ser780)-pRB, and phospho(thr37/46)-4EBP1 in a time-dependent manner. Wortmannin, an inhibitor of the PI3K/ Akt pathway, attenuated the vanillic acid-mediated proliferation of DPCs. Vanillic acid-induced progression of the cell-cycle was also suppressed by wortmannin. Moreover, vanillic acid increased the levels of Wnt/ß-catenin proteins, such as phospho(ser9)- glycogen synthase kinase-3ß, phospho(ser552)-ß-catenin, and phospho(ser675)-ß-catenin. We found that vanillic acid increased the levels of cyclin D1 and Cox-2, which are target genes of ß-catenin, and these changes were inhibited by wortmannin. To investigate whether vanillic acid affects the downregulation of ß-catenin by dihydrotestosterone (DHT), implicated in the development of androgenetic alopecia, DPCs were stimulated with DHT in the presence and absence of vanillic acid for 24 h. Western blotting and confocal microscopy analyses showed that the decreased level of ß-catenin after the incubation with DHT was reversed by vanillic acid. These results suggest that vanillic acid could stimulate anagen and alleviate hair loss by activating the PI3K/Akt and Wnt/ß-catenin pathways in DPCs.

17.
Nutrients ; 12(5)2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32397306

RESUMO

Anticancer effects of L-ascorbic acid (Vitamin C, L-AA) have been reported in various types of cancers. L-AA intake reduces breast cancer recurrence and mortality; however, the role of L-AA in the treatment of breast cancer remains poorly understood. In this study, we investigated the effect and mechanism action of L-AA on breast cancer growth. L-AA inhibited the growth of breast cancer cells by inducing apoptotic cell death at the evaluated treatment concentrations without affecting normal cells. Moreover, L-AA induces autophagosome formation via regulation of mammalian target of rapamycin (mTOR), Beclin1, and autophagy-related genes (ATGs) and increased autophagic flux. Notably, we observed that L-AA increased p62/SQSTM1 (sequestosome 1) protein levels. Accumulation of p62 protein in cancer cells in response to stress has been reported, but its role in cancer regulation remains controversial. Here, we demonstrated that L-AA-induced p62 accumulation is related to L-AA-induced breast cancer growth inhibition. Furthermore, L-AA induced endoplasmic reticulum (ER) stress via the IRE-JNK-CHOP (inositol-requiring endonuclease-c-Jun N-terminal kinase-C/EBP homologous protein) signaling pathways, which increased the nuclear levels of p62/SQSTM1. These findings provide evidence that L-AA-induced ER stress could be crucial for p62 accumulation-dependent cell death, and L-AA can be useful in breast cancer treatment.


Assuntos
Ácido Ascórbico/farmacologia , Neoplasias da Mama/genética , Núcleo Celular/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Mama/patologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Endorribonucleases/metabolismo , Feminino , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteína Sequestossoma-1/metabolismo , Fator de Transcrição CHOP/metabolismo
18.
J Toxicol Environ Health A ; 83(9): 341-350, 2020 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-32340567

RESUMO

Ambient particulate matter (PM) is associated with adverse health consequences. However, the influence of PM on the innate immune system is poorly understood. The aim of the present study was to examine the effect of diesel particulate matter 2.5 µm (PM2.5, SRM1650b) on dendritic cells. PM2.5 significantly reduced cytokine levels of interleukin (IL)-12 p40, IL-6 and TNF-α levels in CpG-DNA (TLR9 ligand)-stimulated dendritic cells. To determine the mechanisms underlying this observed inhibition induced by PM2.5, western blot analysis was conducted. PM2.5 was found to downregulate ERK1/2, JNK1/2, p38 MAPKs, and NF-κB pathways. PM2.5 exposure decreased TLR9-dependent NF-κB and activator protein (AP-1) reporter luciferase activities. Our findings demonstrate that PM2.5 reduced the production of cytokines which may be associated with inhibition of MAPK and NF-κB signaling pathway. Further, data suggest the immunosuppressive effect of PM2.5 on the innate immune cells may lead to serious damage to the host immune system.


Assuntos
Citocinas/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Gasolina/efeitos adversos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , NF-kappa B/efeitos dos fármacos , Material Particulado/efeitos adversos , Receptor Toll-Like 9/efeitos dos fármacos , Animais , Citocinas/metabolismo , Feminino , Humanos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Animais , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
Environ Pollut ; 262: 114301, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32155554

RESUMO

Although several studies have linked PM2.5 (particulate matter with a diameter less than 2.5 µm) to ocular surface diseases such as keratitis and conjunctivitis, very few studies have previously addressed its effect on the retina. Therefore, the aim of this study was to evaluate the effect of PM2.5 on epithelial-mesenchymal transition (EMT), a process involved in disorders of the retinal pigment epithelial (RPE) on APRE-19 cells. PM2.5 changed the phenotype of RPE cells from epithelial to fibroblast-like mesenchymal, and increased cell migration. Exposure to PM2.5 markedly increased the expression of mesenchymal markers, but reduced the levels of epithelial markers. Moreover, PM2.5 promoted the phosphorylation of MAPKs and the expression of transforming growth factor-ß (TGF-ß)-mediated nuclear transcriptional factors. However, these PM2.5-mediated changes were completely reversed by LY2109761, a small molecule inhibitor of the TGF-ß receptor type I/II kinases, and N-acetyl-L-cysteine (NAC), a reactive oxygen species (ROS) scavenger. Interestingly, NAC, but not LY2109761, effectively restored the PM2.5-induced mitochondrial defects, including increased ROS, decreased mitochondrial activity, and mitochondrial membrane potential disruption. Collectively, our findings indicate that the TGF-ß/Smad/ERK/p38 MAPK signaling pathway is activated downstream of cellular ROS during PM2.5-induced EMT. The present study provides the first evidence that EMT of RPE may be one of the mechanisms of PM2.5-induced retinal dysfunction.


Assuntos
Células Epiteliais , Transição Epitelial-Mesenquimal , Humanos , Espécies Reativas de Oxigênio , Pigmentos da Retina , Fator de Crescimento Transformador beta
20.
Int J Med Sci ; 17(1): 63-70, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929739

RESUMO

The skin is one of the large organs in the human body and the most exposed to outdoor contaminants such as particulate matter < 2.5 µm (PM2.5). Recently, we reported that PM2.5 induced cellular macromolecule disruption of lipids, proteins, and DNA, via reactive oxygen species, eventually causing cellular apoptosis of human keratinocytes. In this study, the ethanol extract of Cornus officinalis fruit (EECF) showed anti-oxidant effect against PM2.5-induced cellular oxidative stress. EECF protected cells against PM2.5-induced DNA damage, lipid peroxidation, and protein carbonylation. PM2.5 up-regulated intracellular and mitochondrial Ca2+ levels excessively, which led to mitochondrial depolarization and cellular apoptosis. However, EECF suppressed the PM2.5-induced excessive Ca2+ accumulation and inhibited apoptosis. The data confirmed that EECF greatly protected human HaCaT keratinocytes from PM2.5-induced oxidative stress.


Assuntos
Cornus/química , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Pele/efeitos dos fármacos , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Dano ao DNA/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Material Particulado/efeitos adversos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Pele/patologia
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