RESUMO
Deep seawater (DSW) has been investigated for its lipid-lowering effects, but clinical evidence is still far from conclusive. Therefore, this study was conducted to examine the effects of refined DSW (RDSW) on hypercholesterolemia. In this randomized, double-blind, placebo-controlled trial, 78 Korean participants were randomized to either an RDSW group that drank RDSW for 8 weeks or a placebo group. Clinical laboratory information was collected from all subjects at 0, 4, and 8 weeks. Both groups showed a significant reduction in total cholesterol (TC), whereas only the RDSW group demonstrated a significant decrease in low-density lipoprotein cholesterol (LDL-c) during the study. Stratified analysis of both groups revealed a significant reduction of TC in the moderately high TC subgroup. However, only the RDSW exhibited a significant decline of LDL-c in the high LDL-c subgroup. In addition, lipoprotein(a) decreased significantly in the RDSW group, but not in the placebo. RDSW did not affect other lipid profiles, including high-density lipoprotein cholesterol (HDL-c), triglyceride, free fatty acid, apolipoproteins, and other markers including inflammation marker, hematological parameters, blood and urine chemistry, and vital signs. RDSW improved lipid profiles by decreasing TC and LDL-c while maintaining HDL-c levels in people with hypercholesterolemia.
Assuntos
Anticolesterolemiantes/uso terapêutico , Hipercolesterolemia , Água do Mar/química , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Método Duplo-Cego , Humanos , Hipercolesterolemia/tratamento farmacológico , Lipídeos/sangue , República da CoreiaRESUMO
Arctigenin, a member of the Asteraceae family, is a biologically active lignan that is consumed worldwide due to its several health benefits. However, its use may pose a problem for patients with estrogen receptor (ER)α-positive breast cancer, since studies have shown that arctigenin is a phytoestrogen that exerts a proliferative effect by binding to the ER. Thus, in this study, we examined the effect of arctigenin on ERα-positive MCF-7 human breast cancer cells to determine whether the consumption of arctigenin is safe for patients with breast cancer. First, we found that arctigenin inhibited the viability of the MCF-7 cells, and colony formation assay confirmed that this effect was cytotoxic rather than cytostatic. The cytotoxic effects were not mediated by cell cycle arrest, apoptosis, or necroptosis, despite DNA damage, as indicated by poly(ADP-ribose) polymerase (PARP) cleavage and phosphorylated H2A.X. An increase in lipidated LC3, a marker of autophagosome formation, was observed, indicating that autophagy was induced by arctigenin, which was found to be triggered by the inhibition of the mechanistic target of rapamycin (mTOR) pathway. We then examined the effects of arctigenin on ERα expression and determined whether it affects the sensitivity of the cells to tamoxifen, as tamoxifen is commonly used against hormone-responsive cancers and is known to act via the ERα. We found that treatment with arctigenin effectively downregulated ERα expression, which was found to be a consequence of the inhibition of the mTOR pathway. However, treatment with arctigenin in combination with tamoxifen did not affect the sensitivity of the cells to tamoxifen, but instead, exerted a synergistic effect. On the whole, our data indicate that the phytoestrogen, arctigenin, mainly targeted the mTOR pathway in ERα-positive MCF-7 human breast cancer cells, leading to autophagy-induced cell death and the downregulation of ERα expression. Furthermore, the synergistic effects between arctigenin and tamoxifen suggest that the consumption of arctigenin is not only safe for patients with hormone-sensitive cancers, but may also be an effective co-treatment.
Assuntos
Autofagia/efeitos dos fármacos , Receptor alfa de Estrogênio/efeitos dos fármacos , Furanos/farmacologia , Lignanas/farmacologia , Fitoestrógenos/farmacologia , Serina-Treonina Quinases TOR/efeitos dos fármacos , Sinergismo Farmacológico , Receptor alfa de Estrogênio/biossíntese , Feminino , Humanos , Células MCF-7 , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Tamoxifeno/farmacologiaRESUMO
Arctigenin is a plant lignan extracted from Arctium lappa that has been shown to have estrogenic properties. In spite of the health benefits of phytoestrogens reducing the risk of osteoporosis, heart disease, and menopausal symptoms, its benefits against the risk of breast cancer have not been fully elucidated. Thus, we investigated the effects of arctigenin on metastasis of breast cancer using both estrogen receptor (ER)-positive MCF-7 and ER-negative MDA-MB-231 human breast cancer cell lines to see if the effects are dependent on the status of ER expression. In ER-positive MCF-7 cells, arctigenin efficiently inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell migration and invasion. The activity of crucial metastatic protease matrix metalloprotease (MMP)-9 in gelatin zymography was also efficiently decreased by arctigenin, as well as its mRNA expression. Notably, arctigenin exhibited similar anti-metastatic effects even in ER-negative MDA-MB-231 cells, suggesting that the anti-metastatic effects of arctigenin were not exerted via the ER. The upstream signaling pathways involved in the regulation of MMP-9 and urokinase plasminogen activator (uPA) were analyzed using western blotting. The activation of Akt, NF-κB and MAPK (ERK 1/2 and JNK 1/2) was found to be inhibited. Taken together, these data suggest that arctigenin confers anti-metastatic effects by inhibiting MMP-9 and uPA via the Akt, NF-κB and MAPK signaling pathways on breast cancer, regardless of ER expression. Therefore, we propose that the intake of arctigenin could be an effective supplement for breast cancer patients.