Piperlongumine induces apoptosis and autophagy via the PI3K/Akt/mTOR pathway in KB human cervical cancer cells.

Natural products are continuously being researched to develop safe and effective treatment options for cervical cancer, the fourth most common cancer in women. Piperlongumine (PL), an amide alkaloid mainly present in long pepper, exhibits neuroprotective and anti-cancer properties. However, the specific effect of PL in cervical cancer and the relationship between the anti-cancer pathway and autophagy remain unclear. Therefore, we aimed to investigate PL-induced apoptosis in KB human cervical cancer cells and the relationship between apoptosis and autophagy therein. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and wound-healing assays showed that PL treatment suppressed KB cell viability and proliferation. Apoptosis was identified through 4',6-diamidino-2-phenylindole and annexin V-propidium iodide staining, increased cleaved-poly (ADP-ribose) polymerase and Bcl-2 associated X levels, and decreased B cell lymphoma 2 levels. Acridine orange staining and increased microtubule-associated protein 1A/1B-light chain 3-II and Beclin-1 levels confirmed autophagy. We determined that KB cell-related autophagy exerted cytoprotective effects using the autophagy inhibitors 3-methyladenine and hydroxychloroquine. PL treatment promoted apoptosis by inhibiting the phosphatidylinositol-3-kinase (PI3K)/protein kinase B/mammalian target of rapamycin pathway in KB cells; inhibiting the pathway using PI3K inhibitors increased autophagy. We suggest that PL is a potential natural anticancer agent for cervical cancer treatment.

Genotoxic carcinogen 7,12-dimethylbenz[a]anthracene inhibits gap junction intercellular communication through post-transcriptional and post-translational processing involved in connexin 43 stability.

Gap junctional intercellular communication (GJIC) is composed of connexin (Cx) and plays an important role in maintaining intracellular homeostasis. Loss of GJIC is involved in the early stages of cancer pathways of non-genotoxic carcinogens; however, the effect of genotoxic carcinogens, including polycyclic aromatic hydrocarbons (PAHs), on GJIC function remains unclear. Therefore, we determined whether and how a representative PAH 7,12-dimethylbenz[a]anthracene (DMBA) suppresses GJIC in WB-F344 cells. First, DMBA significantly inhibited GJIC and dose-dependently reduced Cx43 protein and mRNA expression. In contrast, Cx43 promoter activity was upregulated after DMBA treatment via the induction of specificity protein 1 and hepatocyte nuclear factor 3ß, indicating that the promoter-independent loss of Cx43 mRNA can be associated with the inhibition of mRNA stability, which was verified by actinomycin D assay. In addition to a decrease in mRNA stability involved in human antigen R, we also observed DMBA-induced acceleration of Cx43 protein degradation, which was closely related to the loss of GJIC through Cx43 phosphorylation via MAPK activation. In conclusion, the genotoxic carcinogen DMBA suppresses GJIC by inhibiting post-transcriptional and post-translational processing of Cx43. Our findings suggest that the GJIC assay is an efficient short-term screening test for predicting the carcinogenic potential of genotoxic carcinogens.

Chrysin Induces Apoptosis and Autophagy in Human Melanoma Cells via the mTOR/S6K Pathway.

Chrysin is known to exert anti-inflammatory, antioxidant, and anticancer effects. The aim of this study was to investigate the anticancer effects of chrysin in the human melanoma cells A375SM and A375P. The results obtained demonstrated successful inhibition of the viability of these cells by inducing apoptosis and autophagy. This was confirmed by the level of apoptosis-related proteins: Bax and cleaved poly (ADP-ribose) polymerase both increased, and Bcl-2 decreased. Moreover, levels of LC3 and Beclin 1, both autophagy-related proteins, increased in chrysin-treated cells. Autophagic vacuoles and acidic vesicular organelles were observed in both cell lines treated with chrysin. Both cell lines showed different tendencies during chrysin-induced autophagy inhibition, indicating that autophagy has different effects depending on the cell type. In A375SM, the early autophagy inhibitor 3-methyladenine (3-MA) was unaffected; however, cell viability decreased when treated with the late autophagy inhibitor hydroxychloroquine (HCQ). In contrast, HCQ was unaffected in A375P; however, cell viability increased when treated with 3-MA. Chrysin also decreased the phosphorylation of mTOR/S6K pathway proteins, indicating that this pathway is involved in chrysin-induced apoptosis and autophagy for A375SM and A375P. However, studies to elucidate the mechanisms of autophagy and the action of chrysin in vivo are still needed.

Myricetin induces apoptosis and autophagy in human gastric cancer cells through inhibition of the PI3K/Akt/mTOR pathway.

Myricetin, a natural flavonoid present in berries, nuts, and green tea, is well-known for its anticancer properties. Even though several previous studies have reported the anticancer effects induced by myricetin, these effects have not yet been confirmed in the adenocarcinoma gastric cell line (AGS). Moreover, the exact mechanisms of myricetin-induced apoptosis and autophagy have not been clearly identified either. Therefore, in this study, we aimed to examine the role of myricetin in inducing apoptosis and autophagy in AGS gastric cancer cells. First, the survival rate of AGS gastric cancer cells was assessed using the 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) cell viability assay. Thereafter, the rate of apoptosis was analyzed using4',6-diamidino-2-phenylindole (DAPI) staining as well as annexin V and propidium iodide (PI) staining, and the expression of the proteins associated with apoptosis, PI3K/Akt/mTOR pathway, and autophagy was examined by western blotting. We observed that myricetin reduced the survival rate of AGS gastric cancer cells by inhibiting the PI3K/Akt/mTOR pathway, thereby inducing apoptosis and autophagy. Similar results were also obtained in vivo, and tumor growth was inhibited. Therefore, in the AGS gastric cancer cells, myricetin seems to inhibit the PI3K/Akt/mTOR pathway, which in turn leads to apoptosis in vitroand in vivo, cell-protective autophagy, as well as inhibition of cancer cell proliferation. These results indicate the potential of myricetin as a natural anticancer agent.

Histamine causes an imbalance between pro-angiogenic and anti-angiogenic factors in the retinal pigment epithelium of diabetic retina via H4 receptor/p38 MAPK axis.

INTRODUCTION: Systemic histaminergic activity is elevated in patients with diabetes mellitus. There are a few studies suggesting that histamine is implicated in the pathogenesis of diabetes, but the exact role of histamine in the development of diabetic retinopathy is unclear. The aim of this study was to investigate the role of histamine receptor H4 (HRH4) in the regulation of retinal pigment epithelium (RPE)-derived pro-angiogenic and anti-angiogenic factors under diabetic conditions. RESEARCH DESIGN AND METHODS: The levels of vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), histamine and histidine decarboxylase (HDC) in the serum and vitreous samples of patients with diabetes were compared with those of patients without diabetes. The effect of hyperglycemia on expression levels of HRH4, VEGF, IL-6 and pigment epithelium-derived factor (PEDF) in the RPE was determined. The role of HRH4 in high glucose-induced regulation of VEGF, IL-6 and PEDF in ARPE-19 cells and the underlying regulatory mechanism were verified using an RNA interference-mediated knockdown study. RESULTS: The serum and vitreous levels of VEGF, IL-6, histamine and HDC were more increased in patients with diabetic retinopathy than in patients without diabetes. HRH4 was overexpressed in RPE both in vitro and in vivo. Histamine treatment upregulated VEGF and IL-6 and downregulated PEDF expression in ARPE-19 cells cultivated under hyperglycemic conditions. Hyperglycemia-induced phosphorylation of p38 and subsequent upregulation of VEGF and IL-6 and downregulation of PEDF were dampened by small interfering RNA-mediated knockdown of HRH4 in ARPE-19 cells. CONCLUSIONS: Taken together, HRH4 was a critical regulator of VEGF, IL-6 and PEDF in the RPE under hyperglycemic conditions and the p38 mitogen-activated protein kinase pathway mediated this regulatory mechanism.

Apigenin induces apoptosis by regulating Akt and MAPK pathways in human melanoma cell A375SM.

Apigenin, an aromatic compound, exhibits antioxidant, anti­inflammatory and anti­viral effects. The present study aimed to investigate the effects of apigenin on cell proliferation and apoptosis of human melanoma cells A375P and A375SM. Therefore, melanoma cells were treated with apigenin to determine its anti­proliferative and survival effects, using wound healing and MTT assays. The results revealed that melanoma cell viability was decreased in a dose­dependent manner. Furthermore, chromatin condensation, indicating apoptosis, was significantly increased in a dose­dependent manner, as demonstrated by DAPI staining. In addition, increased apoptosis rate following treatment with apigenin was confirmed by Annexin V­propidium iodide staining. The changes in the expression levels of apoptosis­related proteins in A375P and A375SM melanoma cells were subsequently detected using western blot analysis. The results demonstrated that the protein expression levels of Bcl­2 were decreased, whereas those of Bax, cleaved poly ADP­ribose polymerase, cleaved caspase­9 and p53 were upregulated in a dose­dependent manner in apigenin­treated cells compared with those noted in untreated cells. In addition, in apigenin­treated A375P cells, phosphorylated (p)­p38 was upregulated and p­extracellular signal­regulated kinase (ERK), p­c­Jun N­terminal kinase (JNK) and p­protein kinase B (Akt) were downregulated. However, in A375SM cells, apigenin treatment increased p­ERK and p­JNK and decreased p­p38 and p­Akt protein expression levels. Subsequently, the inhibitory effect of apigenin on tumor growth was investigated in vivo. Tumor volume was significantly reduced in the 25 and 50 mg/kg apigenin­treated groups compared with the control group. Additionally, a TUNEL assay was performed to detect apoptotic cells. Immunohistochemical staining also revealed elevated p­ERK expression in the apigenin­treated group compared with the control group. Overall, the findings of the present study indicated that apigenin attenuated the growth of A375SM melanoma cells by inducing apoptosis via regulating the Akt and mitogen­activated protein kinase signaling pathways.

Ccrn4l as a pre-dose marker for prediction of cisplatin-induced hepatotoxicity susceptibility.

Clinical cisplatin use is often limited by its drug-induced liver injury (DILI). Particularly, individual differences in susceptibility to DILI can cause life-threatening medical conditions. This study aimed to uncover the inherent genetic factors determining individual variations in hepatotoxicity susceptibility. Rats were subjected to liver biopsy and a 3-week postoperative recovery period before cisplatin administration. At 2 days post-treatment with cisplatin, the rats exhibited histopathological and serum biochemical alterations in the liver, and changes in hydrogen peroxide and cytochrome P450-2E1 levels. Based on these results of liver-related biochemical markers, 32 rats were grouped into the susceptible (top five) and resistant (bottom five) groups. Using RNA-sequencing, we compared gene expressions in the liver pre-biopsied from these two groups before cisplatin treatment and found 161 differently expressed genes between the Susceptible and Resistant groups. Among them, the clock-controlled Ccrn4l responsible for 'rhythmic process' was identified as a common gene downregulated inherently prior to drug exposure in both cisplatin- and acetaminophen-sensitive animals. Additionally, low Ccrn4l levels before cisplatin treatment in the Susceptible group were maintained even after treatment, with decreased antioxidants, increased nitration, and apoptosis. The relationship of Ccrn4l with catalase and mitochondrial RNAs in the liver was confirmed by correlation of their hepatic levels among individuals and similar patterns of circadian variation in their mRNA expression. Remarkably, Ccrn4l knockdown promoted cisplatin-induced mitochondrial dysfunction in WB-F344 cells with antioxidant catalase and apoptosis-related Bax changes. Inherent individual hepatic Ccrn4l level might be a novel factor affecting cisplatin-induced hepatotoxicity susceptibility, possibly through regulation of mitochondrial and antioxidant functions.

Preclinical study of safety of Dendropanax morbifera Leveille leaf extract: General and genetic toxicology.

ETHNOPHARMACOLOGY RELEVANCE: Dendropanax morbifera Leveille (DM) has been used in traditional medicines for infectious and skin diseases, and dysmenorrhea. It exhibits a diverse therapeutic potential including anti-cancer, anti-thrombotic, anti-diabetic, anti-oxidant, and anti-inflammatory activities. AIM OF THE STUDY: Despite promising health benefits of DM, knowledge of its potential adverse effects is very limited. The current study focused on the investigation of subchronic toxicity and genotoxicity of extract obtained from DM according to the test guidelines published by the Organization for Economic Cooperation and Development. MATERIALS AND METHODS: We conducted a toxicological evaluation of DM extracts using 14-day repeated-dose toxicity study and 13-week repeated-dose toxicity study in Sprague-Dawley rats administered orally at doses of 500, 1000, or 2000 mg/kg/day. The clastogenicity of DM extract was also evaluated by in vitro chromosome aberration assay and in vivo micronucleus assay. RESULTS: Assessment of subchronic toxicity of DM extract by oral administration in rats revealed unremarkable treatment-related findings with respect to food/water consumption, body weight, mortality, urinalysis, hematology, serum biochemistry, necropsy, organ weight and histopathology at doses of 500, 1000, and 2000 mg/kg. Accordingly, the level of no-observed-adverse-effect for DM extract in 13-week subchronic toxicity study was considered to be 2000 mg/kg/day in rats. The data observed from in vitro chromosome aberration assay and in vivo micronucleus assay exclude any clastogenicity of DM extract. CONCLUSION: The results suggest that the oral consumption of DM extract has no adverse effects in humans and represents a safe traditional medicine.

Antitumor and Apoptosis-inducing Effects of Piperine on Human Melanoma Cells.

BACKGROUND/AIM: Piperine is a major pungent alkaloid present in black pepper (Piper nigrum L). This study investigated the potential anticancer effects of piperine on human melanoma cells and explored the potential pharmacological mechanisms in vitro and in vivo. MATERIALS AND METHODS: Studies were performed using the MTT assay, 4',6-diamidino-2-phenylindole (DAPI) staining, western blotting, a xenograft model, the terminal deoxynucleotidyl transferase dUTP nick end labeling assay, and immunohistochemistry. RESULTS: Piperine inhibited the growth of melanoma cells. Several apoptotic events were observed following treatment, as revealed by DAPI staining. Piperine increased the expression of BCL2-associated X, apoptosis regulator (BAX), cleaved poly(ADP-ribose)polymerase, cleaved caspase-9, phospho-c-Jun N-terminal kinase and phospho-p38, and reduced that of B-cell lymphoma 2 (BCL2), X-chromosome-linked inhibitor of apoptosis, and phospho-extracellular signal-regulated protein kinase (ERK1/2) in a concentration-dependent manner. Treatment of mice for 4 weeks with piperine inhibited tumor growth without apparent toxicity. Piperine increased the expression of apoptotic cells and cleaved-caspase-3 protein and reduced the expression of phospho-ERK1/2 protein in melanoma tumors. CONCLUSION: Piperine suppressed the growth of human melanoma cells by the induction of apoptosis via the inhibition of tumor growth of human melanoma cells and tumor xenograft models.

Optimizing the cutoff for the identification of skin sensitizers by the HaCaSens assay: Introducing an ROC-analysis-based cutoff approach.

The worldwide restricted use of animal testing makes it challenging to identify the skin sensitizing potentials of newly manufactured products. The HaCaSens assay has shown promise as an in vitro skin sensitizing assay comparable to existing assays, and is currently under pre-validation. However, there is little agreement on how to assess the results of the assay to discriminate sensitizers from non-sensitizers as the stimulation index (SI) cutoff value was arbitrarily chosen without appropriate statistical methods. Here, we investigated the SI cutoff values in identifying sensitizers to obtain the optimal value. Sensitivities and specificities were calculated for a set of 30 test substances, and plotted in receiver operator characteristics (ROC) curves. The SI cutoff values with the highest sum of sensitivity and specificity according to LLNA data were 2.2, 1.8 and 3.0 for interleukin 1α (IL-1α), interleukin 6 (IL-6), and the combination of the two cytokines respectively. Also, the same statistical analysis of human data demonstrated optimal SI cutoff values 2.0, 2.0 and 3.2 for the same respective parameters. When considering the predictive capacity of each possible SI cutoff value determined by ROC curves, the optimal value for HaCaSens is 3.0 for the combination of IL-1α and IL-6 as it had the highest sensitivity (90.9%), specificity (75.0%) and accuracy (86.7%) based on LLNA data. Thus, we recommend the wide use of the SI cutoff value of 3.0 to ensure consistent endpoints.

Assessment of acute, 14-day, and 13-week repeated oral dose toxicity of Tiglium seed extract in rats.

BACKGROUND: Seed of mature Croton tiglium Linne, also known as Tiglium seed (TS), has been widely used as a natural product due to its several health beneficial properties including anti-tumor and antifungal activities. Despite its ethnomedicinal beneficial properties, toxicological information regarding TS extract, especially its long-term toxicity, is currently limited. Therefore, the objective of the present study was to evaluate acute and subchronic toxicity of TS extract in rats after oral administration following test guidelines of the Organization for Economic Cooperation and Development (OECD). METHODS: Toxicological properties of TS extract were evaluated by toxicity assays to determine its single-dose acute toxicity (125, 250, 500, 1000, or 2000 mg/kg), 14-day repeated-dose toxicity (125, 250, 500, 1000, or 2000 mg/kg) and 13-week repeated-dose toxicity (31.25, 62.5, 125, 250, and 500 mg/kg) in Sprague-Dawley rats and F344 rats. Hematological, serum biochemical, and histopathological parameters were analyzed to determine its median lethal dose (LD50) and no-observed-adverse-effect-level (NOAEL). RESULTS: Oral single dose up to 2000 mg/kg of TS extract resulted in no mortalities or abnormal clinical signs. In 13-week toxicity study, TS extract exhibited no dose-related changes (mortality, body weight, food/water consumption, hematology, clinical biochemistry, organ weight, or histopathology) at dose up to 500 mg/kg, the highest dosage level suggested based on 14-day repeat-dose oral toxicity study. CONCLUSION: Acute oral LD50 of TS extract in rats was estimated to be greater than 2000 mg/kg. NOAEL of TS extract administered orally was determined to be 500 mg/kg/day in both male and female rats. Results from these acute and subchronic toxicity assessments of TS extract under Good Laboratory Practice regulations indicate that TS extract appears to be safe for human consumption.

Lactic Acid Upregulates VEGF Expression in Macrophages and Facilitates Choroidal Neovascularization.

Purpose: Lactic acid, the end product of glycolysis, has emerged as an immune-modulating metabolite in various diseases. In this study, we aimed to examine whether lactic acid contributes to the disease pathogenesis of choroidal neovascularization (CNV) and to investigate the role of macrophages in CNV pathogenesis. Methods: CNV was induced by laser photocoagulation in C57BL/6J mice. Lactic acid concentration was measured in the RPE-choroid region. Macrophage infiltration and VEGF were quantified by flow cytometry. VEGF-positive areas and CNV lesions were measured by flat-mount immunofluorescence staining. To inhibit lactic acid uptake in vivo, alpha-cyano-4-hydroxycinnamic acid (α-CHC), a monocarboxylate transporter (MCT) blocker, was injected intravitreally 1 day after laser. VEGF productions were measured in ARPE-19, THP-1 cells, and human umbilical vein endothelial cells (HUVECs) by quantitative PCR and ELISA. Angiogenic activity of lactic acid-treated macrophages was assessed by HUVEC tube formation assay. Results: Lactic acid was significantly increased in the RPE-choroid region of CNV-induced mice. Lactic acid upregulated VEGFA mRNA and VEGF protein expressions in THP-1 macrophages, but did not in ARPE-19 or HUVECs. THP-1 macrophages treated with lactic acid increased the angiogenesis of endothelial cells independent of MCT activity. Intravitreal injection of α-CHC substantially reduced the VEGF-positive area that colocalized with F4/80-positive macrophages. CNV lesions were also significantly reduced following α-CHC injection compared with vehicle-injected controls. Conclusions: To our knowledge, these results show for the first time the role of lactic acid in facilitating neovascularization through macrophage-induced angiogenesis. We suggest that targeting macrophage metabolism can be a promising strategy for CNV treatment.

In vitro and in vivo safety studies of cinnamon extract (Cinnamomum cassia) on general and genetic toxicology.

Cinnamomum cassia has been widely used as a natural product to treat diseases in Asia due to its diverse pharmacological functions including anti-inflammatory, anti-oxidant, anti-microbial, anti-diabetic, and anti-tumor effects. Despite its ethnomedicinal benefits, little information regarding its toxicity is currently available. The aim of this study was to evaluate its potential long-term toxicity and genotoxicity in compliance with test guidelines of the Organization for Economic Cooperation and Development. A 13-week repeat-dose oral toxicity study revealed that body weights of rats were normal after receiving cinnamon extract at up to 2000 mg/kg. High-dose intake of cinnamon extract (2000 mg/kg) showed potential nephrotoxicity and hepatotoxicity to both males and females as evidenced by obvious increases of kidney/liver weight along with a small but statistically elevation of total cholesterol level. Overall findings from genetic toxicity testing battery including Ames test, in vitro mammalian cell micronucleus assay, and in vivo bone marrow micronucleus assay indicated that cinnamon extract was not mutagenic or clastogenic. In conclusion, cinnamon extract may possess potential nephrotoxicity and hepatotoxicity at dose higher than its recommended daily safe dose. Further study is needed to clarify the mechanism involved in its induction of liver and kidney injury.

Anti­inflammatory effect of quercetin and galangin in LPS­stimulated RAW264.7 macrophages and DNCB­induced atopic dermatitis animal models.

Flavonols are compounds that have been shown to possess potent anti­inflammatory effects in cellular and animal models of inflammation. In the present study, the anti­inflammatory effects and mechanisms of two natural flavonols, quercetin and galangin, in lipopolysaccharide (LPS)­stimulated RAW264.7 macrophages were investigated. It was identified that quercetin and galangin markedly reduced the production of nitric oxide (NO), inducible NO synthase and interleukin­6, and the nuclear translocation of nuclear factor­κB (NF­κB). In addition, LPS­induced activation of extracellular signal­regulated kinase 1/2 (Erk1/2) and c­Jun N­terminal kinase (JNK) was suppressed by quercetin and galangin. Taken together, these data implied that NF­κB, Erk1/2 and JNK may be potential molecular targets of quercetin and galangin in an LPS­induced inflammatory response. Subsequently, the effects of oral administration of quercetin or galangin, either alone or in combination, in a 2,4­dinitrochlorobenzene­induced atopic dermatitis (AD) mouse model were investigated. As a result, measurements of ear thickness and the levels of serum immunoglobulin E, and histological analysis revealed that the two flavonols led to a decrease in inflammation, whereas, in combination, they were even more effective. These results suggested that quercetin and galangin may be promising therapeutic agents for AD. Additionally, their combination may be a novel therapeutic strategy for the prevention of AD.

Enzymatic extract from Ecklonia cava: Acute and subchronic oral toxicity and genotoxicity studies.

Ecklonia cava (EC) is known to have antioxidant, anti-inflammatory, antidiabetic, and anticancer properties. Despite its wide use and beneficial properties, comprehensive toxicological information regarding EC extract is currently limited. Therefore, the purpose of this study was to investigate acute toxicity, subchronic toxicity, and genotoxicity of enzymatic EC extract according to test guidelines published by Organization for Economic Cooperation and Development. The acute oral LD50 values of this EC extract administered to rats and dogs were estimated to be more than 3000 mg/kg BW. In an oral 13-week toxicity study, changes in body weights of rats exposed to the EC extract up to 3000 mg/kg BW were found to be normal. In addition, repeated doses of EC extract failed to influence any systematic parameters of treatment-related toxic symptoms such as food/water consumption, mortality, urinalysis, hematology, serum biochemistry, organ weight, or histopathology. These results indicated that the no-observed-adverse-effect level for the EC extract was 3000 mg/kg/day for male and female rats. Data obtained from Ames test, chromosome aberration assay, and micronucleus assay indicated that EC extract was not mutagenic or clastogenic. Taken together, these results support the safety of enzymatic EC extract as a potential therapeutic for human consumption against various diseases.

Preclinical safety assessment of Angelica acutiloba using a 13-week repeated dose oral toxicity study in rats.

Angelica acutiloba (AA), a Japanese species of Danggui, has been used worldwide as a traditional herbal medicine with several bioactivities including anti-diabetic, anti-allergic, anti-inflammatory, anti-tumor, and anti-obesity. However, there is lack of toxicological data available to evaluate potential long-term toxicity and the no-observed-adverse-effect level (NOAEL) of AA extract in accordance with the test guidelines published by the Organization for Economic Cooperation and Development. In the 14-day repeat-dose toxicity study, no adverse effects on mortality, body weight change, clinical signs, and organ weights was found following repeat oral administration to rats for 14 days (125, 250, 500, 1000, and 2000 mg/kg body weight), leading that 2000 mg/kg is the highest recommended dose of AA extract for the 13-week repeat-dose oral toxicity study. In the 13-week repeat-dose oral toxicity study, the AA extract was orally administered to groups of rats for 13 weeks (125, 250, 500, 1000, and 2000 mg/kg body weight) to compare between control and AA extract groups. The administration of AA extract did not produce mortality or remarkable clinical signs during this 13-week study. And, the data revealed that there were no significant differences in food/water consumption, body weight, hematological parameters, clinical chemistry parameters, gross macroscopic findings, organ weight and histopathology in comparison to the control group. On the basis of these results, the subchronic NOAEL of the AA extract was more than 2000 mg/kg/day when tested in rats. And, the AA extract is considered safe to use orally as a traditional herbal medicine.

Evaluation of in vitro and in vivo genotoxicity of Angelica acutiloba in a standard battery of assays.

Among three representative species of Angelica found in Asian countries, including Korea, China, and Japan, Angelica acutiloba (AA) has been used as traditional herbal medicine with antitumor, anti-inflammatory, anti-obesity, and anti-diabetes activities. In this study, the potential genotoxicity and mutagenicity of the AA extract were examined in a battery of in vitro and in vivo tests (bacterial reverse mutation assay, in vitro chromosomal aberrations assay, and in vivo micronucleus assay) in accordance with the test guidelines for toxicity testing developed by the Organization for Economic Cooperation and Development. Upon testing in the bacterial mutation assay (Ames test) using five Salmonella typhimurium TA98, TA100, TA102, TA1535 and TA1537, no significant increase the number of revertant colonies in the metabolic activation system and non-activation system was noted in the AA extract groups. Also, in the chromosome aberration test, the AA extract did not cause chromosomal aberration with or without metabolic activation by S9 mix. A bone marrow micronucleus test of mice demonstrated that the incidence of micronucleated polychromatic erythrocytes in the AA extract groups (500, 1000 and 2000 mg/kg BW) was equivalent to that of the negative control group. Based on these results from a standard battery of assays, the AA extract was concluded to have no genotoxic at the proper dose.

Ixeris dentata (Thunb. Ex Thunb.) Nakai Extract Inhibits Proliferation and Induces Apoptosis in Breast Cancer Cells through Akt/NF-κB Pathways.

Ixeris dentata (Thunb. Ex Thunb.) Nakai (ID) exhibits various physiological activities, and its related plant derived-products are expected to represent promising cancer therapeutic agents. However, the anticancer effects of ID extract on breast cancer cells classified as estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) are still unknown. In this study, we investigated the anti-cancer effects and analyzed the molecular mechanism of ID extract in T47D, MCF-7 (ER-, PR-positive, HER2-negative), SK-BR-3(ER-, PR-negative, HER2-positive), and MDA-MB-231 (Triple-negative) through in vitro studies. Additionally, we examined its anti-tumor effects through in vivo studies. Our findings indicated that ID extract-induced apoptosis was mediated via various survival pathways on four breast cancer cells by identifying the factors including Bcl-2 family, phospho-Akt and phospho-nuclear factor-κB (NF-κB). Based on in vitro findings that induced apoptosis via Akt-NF-κB signaling, we investigated the effects of ID extract on mice bearing MDA-MB-231 cells. The results showed that ID extract significantly decreased MDA-MB-231 tumor volume and weight via inducing apoptosis by suppressing phospho-Akt. Overall, these results indicate that ID extract induces apoptosis through the Akt-NFκB signaling pathway in MDA-MB-231 breast cancer cells and tumors, and it may serve as a therapeutic agent for triple-negative human breast cancer.

Discrimination of skin sensitizers from non-sensitizers by interleukin-1α and interleukin-6 production on cultured human keratinocytes.

In vitro testing methods for classifying sensitizers could be valuable alternatives to in vivo sensitization testing using animal models, such as the murine local lymph node assay (LLNA) and the guinea pig maximization test (GMT), but there remains a need for in vitro methods that are more accurate and simpler to distinguish skin sensitizers from non-sensitizers. Thus, the aim of our study was to establish an in vitro assay as a screening tool for detecting skin sensitizers using the human keratinocyte cell line, HaCaT. HaCaT cells were exposed to 16 relevant skin sensitizers and 6 skin non-sensitizers. The highest dose used was the dose causing 75% cell viability (CV75) that we determined by an MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The levels of extracellular production of interleukin-1α (IL-1α) and IL-6 were measured. The sensitivity of IL-1α was 63%, specificity was 83% and accuracy was 68%. In the case of IL-6, sensitivity: 69%, specificity: 83% and accuracy: 73%. Thus, this study suggests that measuring extracellular production of pro-inflammatory cytokines IL-1α and IL-6 by human HaCaT cells may potentially classify skin sensitizers from non-sensitizers. Copyright © 2015 John Wiley & Sons, Ltd.

Dual effects of human adipose tissue-derived mesenchymal stem cells in human lung adenocarcinoma A549 xenografts and colorectal adenocarcinoma HT-29 xenografts in mice.

Human adipose tissue-derived mesenchymal stem cells (hATMSCs) have great potential as a therapy for various diseases. However, emerging evidence shows that there are conflicting results concerning effects of hATMSCs on tumor progression. Our objective was to determine whether and how hATMSCs modulate tumor growth. After cancer cell lines were subcutaneously inoculated into BALB/c-nude and hairless severe combined immunodeficient mice, hATMSCs were intratumorally injected into the mice. The growth of the A549 tumors was inhibited by hATMSCs, yet that of the HT-29 tumors was significantly promoted by hATMSCs in the in vivo xenograft models. In vitro study using a co-culture system of cancer cells and hATMSCs was consistent with the in vivo experiments. To reveal the molecular events induced by hATMSCs in the xenograft models, global gene expression profiles of the A549 and HT-29 tumors in the absence or presence of hATMSCs were determined. Significant numbers of genes involved in biological processes were altered in the hATMSC-treated A549 tumors, whereas no biological process was regulated by treatment with hATMSCs in the HT-29 tumors, reflecting the different effects of hATMSCs in the different types of cancer. Notably, histone cluster 1, H2aj and neuropeptide Y receptor Y4 were found to be expressed in direct or inverse proportion to tumor size in both xenograft models. In addition, nuclear factor κB (NF-κB) p65 was differentially phosphorylated by the hATMSCs dependent on the source of the cancer cells. In conclusion, the identified gene profiling and NF-κB signaling provide molecular evidence to explain the conflicting findings in tumor­MSC studies, although further study is needed to confirm these findings using various types of cancer.