Tk Lee

Pinecone of Pinus koraiensis Inducing Apoptosis in Human Lung Cancer Cells by Activating Caspase-3 and its Chemical Constituents

Pinecones from Pinus koraiensisSiebold & Zucc. (Pinaceae), which have historically been treated as an undesired waste by‐product in the processing of seeds, have recently been shown to contain ingredients with potent biological activities, such as polyphenols exhibiting antitumor activity. With this study, we seek to broaden our understanding of antitumor compounds contained in these pinecones beyond just polyphenols. We found that the water extract of P. koraiensis pinecones exhibits significant cytotoxic activity, with IC50 values ranging from 0.62 to 1.73 mg/ml in four human lung cancer cell lines, A549, H1264, H1299, and Calu‐6, irrespective of their p53 status. We also demonstrate that pinecone water extract induces apoptosis associated with caspase‐3 activation in the same cancer cell lines. Chemical investigation of the pinecone water extract revealed eight main components (1 – 8), and their structures were identified as dehydroabietic acid (1), 15‐hydroxy‐7‐oxodehydroabietic acid (2), 7β,15‐dihydroxydehydroabietic acid (3), β‐d‐glucopyranosyl labda‐8(17,13)‐diene‐(15,16)‐lactone‐19‐oate (4), 7α,15‐dihydroxydehydroabietic acid (5), (+)‐(1S,2S,4R)‐limonene‐1,2‐diol (6), sobrerol (7), and 4‐hydroxybenzoic acid (8). These findings suggest a novel biological application of P. koraiensis pinecones in combatting human lung cancer, and further identify the major compounds that could contribute to this anticancer activity.

Curcuzedoalide contributes to the cytotoxicity of Curcuma zedoaria rhizomes against human gastric cancer AGS cells through induction of apoptosis

ETHNOPHARMACOLOGICAL RELEVANCE Curcuma zedoaria Roscoe (Zingiberaceae), also known as white turmeric or zedoaria, has been used in Ayurveda and traditional Chinese medicine to treat various cancers, and it possesses several sesquiterpenoid compounds. OBJECTIVE This study aimed to evaluate the therapeutic effects of a methanolic (MeOH) extract of C. zedoaria rhizomes, as well as its active constituents, against gastric cancer, which is a frequently diagnosed cancer in South Korea. MATERIALS AND METHODS Repeated column chromatography, together with semi-preparative HPLC purification, was used to separate the bioactive constituents from the C. zedoaria MeOH extract. The cytotoxic effects of the C. zedoaria MeOH extract and its active compounds were measured in human gastric cancer AGS cells. Expression of proteins related to apoptosis was evaluated using Western blotting analysis. RESULTS The MeOH extract of C. zedoaria rhizomes exerted a cytotoxic effect on AGS cells (IC50: 96.60 ± 4.87μg/mL). Based on the bioactivity-guided fractionation for antiproliferative activity, a chemical investigation of the MeOH extract led to the isolation of five sesquiterpenes including isoprocurcumenol (1), germacrone (2), curzerenone (3), curcumenol (4), and curcuzedoalide (5). Among these, curcuzedoalide demonstrated the strongest effect in suppressing gastric cancer cell proliferation in a dose-dependent manner with an IC50 value of 125.11±2.77μM. Western blotting analysis showed that curcuzedoalide inhibited AGS human gastric cancer cell viability by activating caspase-8, caspase-9, caspase-3, and PARP, which contributed to apoptotic cell death in AGS human gastric cancer cells. CONCLUSION These data indicate that curcuzedoalide contributed to the cytotoxicity of C. zedoaria by activating the cleavage of caspases and PARP, which are representative markers for apoptosis. Therefore, curcuzedoalide is a positive candidate for the development of novel chemotherapeutics.

Bioactivity-based analysis and chemical characterization of anti-inflammatory compounds from Curcuma zedoaria rhizomes using LPS-stimulated RAW264.7 cells

Inflammation is not only a self-defense response of the innate immune system, but also the pathogenesis mechanism of multiple diseases such as arthritis, neurodegeneration, and cancer. Curcuma zedoaria Roscoe (Zingiberaceae), an indigenous plant of India, has been used traditionally in Ayurveda and folk medicine. As part of our ongoing efforts to screen traditional medicinal plants exhibiting pharmacological potential and to characterize the compounds involved, we examined the anti-inflammatory effects of the MeOH extract of C. zedoaria rhizomes using lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophage cells and found that MeOH extract inhibited the synthesis of nitric oxide (NO) in a dose-dependent manner (IC50: 23.44 ± 0.77 μg/mL). In our efforts to characterize the compounds responsible for these anti-inflammatory effects, bioactivity-guided fractionation of the MeOH extract and chemical investigation of its active hexane-soluble fraction led to the successful isolation of five sesquiterpenes (1-5), the structures of which were elucidated by NMR spectroscopic analysis and LC/MS analysis. Among them, curcuzedoalide (5) exhibited potent inhibitory effects on NO synthesis (IC50: 12.21 ± 1.67 μM) and also suppressed pre-inflammatory protein expression of iNOS and COX-2. Curcuzedoalide (5) was thus determined to be a contributor to the anti-inflammatory effect of C. zedoaria rhizomes and could be a potential candidate for therapeutic applications.

Chemical Characterization of Novel Natural Products from the Roots of Asian Rice (Oryza sativa) that Control Adipocyte and Osteoblast Differentiation

Oryza sativa L. is consumed globally as a staple food, and its roots have been used as a Korean and Chinese medical supplement for protection of the stomach and lungs and for amelioration of vomiting and fever. In our continuing search for biologically effective metabolites from Korean natural materials, we found that an EtOH extract of O. sativa root reciprocally regulated adipocyte and osteoblast differentiation. Chemical analysis of the EtOH extract using a bioassay-guided fractionation protocol led to the isolation and determination of two novel lignans, oryzativols A and B, responsible for these regulatory activities. Using 1D and 2D nuclear magnetic resonance spectroscopic analyses, high-resolution mass spectrometry, and circular dichroism analysis, the structures of the novel compounds were elucidated. We examined their effects on the regulation of mesenchymal stem cell differentiation. Treatment with oryzativol A in the human mesenchymal cell line C3H10T1/2 suppressed gene expression of peroxisome proliferator activated receptor γ, which resulted in a reduction in adipogenesis. Oryzativol A also enhanced the expression of Runx2 and cellular differentiation into osteoblasts in the same mesenchymal stem cell line.

Biological Evaluation of a New Lignan from the Roots of Rice (Oryza sativa)

LC/MS‐based phytochemical analysis of an EtOH extract of the roots of rice (Oryza sativa; Gramineae), which takes a crucial role in the stable crop population in Asia, resulted in the isolation of a new lignan, oryzativol C (1), as a minor component. The chemical structure of compound 1 was unambiguously confirmed using spectroscopic evidence (including 1D‐ and 2D‐NMR data), HR‐ESI‐MS, and CD data analysis. Considering the traditional medicinal efficacy of O. sativa and its importance as a food crop, compound 1 was evaluated for effects on breast cancer cell lines (MDA‐MB‐231) and on glucose‐stimulated insulin secretion in an INS‐1 pancreatic β‐cell line. Compound 1 showed mild cytotoxicity toward the MDA‐MB‐231. Furthermore, compound 1 stimulated insulin secretion in INS‐1 pancreatic β‐cells without inducing cytotoxicity. These results indicate that compound 1 is an active ingredient of O. sativa that offers health benefits including inhibition of breast cancer cell proliferation and hyperglycemia control.

7α,15-Dihydroxydehydroabietic acid from Pinus koraiensis inhibits the promotion of angiogenesis through downregulation of VEGF, p-Akt and p-ERK in HUVECs

Pinus koraiensis pinecones are considered an undesired waste by-product of the processing of seeds. However, recent studies of the potential anti-tumor effects of the pinecones have led to increasing interest in their chemical constituents. The present study examined the potential antiangiogenic effects of the constituents of pinecones and further characterized their underlying mechanisms of action. Chemical investigation of a water extract of P. koraiensis pinecones led to the isolation and identification of the eight main components including five diterpenoids (1-5), two monoterpenes (6,7) and a phenolic acid (8). The structure of the compounds was determined by spectroscopic analysis of NMR spectra and LC/MS analysis. Of the isolated compounds, 7α,15-dihydroxydehydroabietic acid (5) significantly inhibited the promotion of angiogenesis in human umbilical vein endothelial cells (HUVECs). Compound 5 inhibited angiogenesis through downregulation of the VEGF, p-Akt and p-ERK signaling pathways. These results provide experimental evidence of a novel biological activity of 7α,15-dihydroxydehydroabietic acid (5) as a potential antiangiogenic substance. This study also suggests that compound 5 could potentially be a useful adjuvant therapeutic substance for cancer prevention and treatment.