Kyeong Wan Woo1, Oh Wook Kwon2, Sun Yeou Kim3, Sang Zin Choi4, Mi Won Son4, Ki Hyun Kim1, Kang Ro Lee5. 1. Natural Products Laboratory, School of Pharmacy, Sungkyunkwan University, 300 Chonchon-dong, Jangan-ku, Suwon, Gyeonggi-do 440-746, Republic of Korea. 2. Graduate School of East-West Medical Science, Kyung Hee University Global Campus, Yongin 446-701, Republic of Korea. 3. College of Pharmacy, Gachon University, Incheon 406-799, Republic of Korea; Gachon Institute of Pharmaceutical Science, Gachon University, Incheon 406-799, Republic of Korea; Gachon Medical Research Institute, Gil Medical Center, Inchon 405-760, Republic of Korea. 4. Dong-A Pharm Institute, Kiheung, Yongin 449-905, Republic of Korea. 5. Natural Products Laboratory, School of Pharmacy, Sungkyunkwan University, 300 Chonchon-dong, Jangan-ku, Suwon, Gyeonggi-do 440-746, Republic of Korea. Electronic address: krlee@skku.edu.
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE: Dioscorea nipponica (Dioscoreaceae) have been used as traditional medicines for diabetes, inflammatory and neurodegenerative diseases in Korea. The aim of the study was to isolate the bioactive components from the rhizomes of Dioscorea nipponica and to evaluate their anti-neuroinfalmmatory and neuroprotective activities. MATERIAL AND METHODS: The phytochemical investigation of 50% EtOH extract of Dioscorea nipponica using successive column chromatography over silica gel, Sephadex LH-20, and preparative high performance liquid chromatography (HPLC) resulted in the isolation and identification of 17 phenolic derivatives, including four new phenolic compounds (1-4). The structural elucidation of these compounds was based on spectroscopic methods, including 1D and 2D nuclear magnetic resonance (NMR) spectroscopy techniques, mass spectrometry, and optical rotation. All isolated compounds were evaluated for their effects on nerve growth factor (NGF) secretion in a C6 rat glioma cell line and nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV2 cells. The neurite outgrowth of compound 16 was further evaluated by using mouse neuroblastoma N2a cell lines. RESULTS: Three new stilbene derivatives, diosniponol C (1), D (2) and diosniposide A (3) and one new phenanthrene glycoside, diosniposide B (4), together with 13 known compounds were isolated from the rhizomes of Dioscorea nipponica. Of the tested compounds (1-17), phenanthrene, 3,7-dihydroxy-2,4,6-trimethoxy-phenanthrene (16) was the most potent NGF inducer, with 162.35±16.18% stimulation, and strongly reduced NO levels with an IC50 value of 19.56 μM in BV2 microglial cells. Also, it significantly increased neurite outgrowth in N2a cells. CONCLUSIONS: This study supports the ethnopharmacological use of Dioscorea nipponica rhizomes as traditional medicine.
ETHNOPHARMACOLOGICAL RELEVANCE: Dioscorea nipponica (Dioscoreaceae) have been used as traditional medicines for diabetes, inflammatory and neurodegenerative diseases in Korea. The aim of the study was to isolate the bioactive components from the rhizomes of Dioscorea nipponica and to evaluate their anti-neuroinfalmmatory and neuroprotective activities. MATERIAL AND METHODS: The phytochemical investigation of 50% EtOH extract of Dioscorea nipponica using successive column chromatography over silica gel, Sephadex LH-20, and preparative high performance liquid chromatography (HPLC) resulted in the isolation and identification of 17 phenolic derivatives, including four new phenolic compounds (1-4). The structural elucidation of these compounds was based on spectroscopic methods, including 1D and 2D nuclear magnetic resonance (NMR) spectroscopy techniques, mass spectrometry, and optical rotation. All isolated compounds were evaluated for their effects on nerve growth factor (NGF) secretion in a C6 ratglioma cell line and nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV2 cells. The neurite outgrowth of compound 16 was further evaluated by using mouseneuroblastoma N2a cell lines. RESULTS: Three new stilbene derivatives, diosniponol C (1), D (2) and diosniposide A (3) and one new phenanthrene glycoside, diosniposide B (4), together with 13 known compounds were isolated from the rhizomes of Dioscorea nipponica. Of the tested compounds (1-17), phenanthrene, 3,7-dihydroxy-2,4,6-trimethoxy-phenanthrene (16) was the most potent NGF inducer, with 162.35±16.18% stimulation, and strongly reduced NO levels with an IC50 value of 19.56 μM in BV2 microglial cells. Also, it significantly increased neurite outgrowth in N2a cells. CONCLUSIONS: This study supports the ethnopharmacological use of Dioscorea nipponica rhizomes as traditional medicine.
Authors: Mohamed R Habib; Ahmed A Hamed; Rasha E M Ali; Khaled M Zayed; Rasha M Gad El-Karim; Rehab Sabour; Hanaa M Abu El-Einin; Mosad A Ghareeb Journal: Pharm Biol Date: 2022-12 Impact factor: 3.889