ABSTRACT
BACKGROUND: Combination drug therapy has become an effective strategy for inflammation control. The antiinflammatory capacities of silibinin and thymol have each been investigated on its own, but little is known about the synergistic anti-inflammatory effects of these two compounds. PURPOSE: This study aims to investigate the synergistic anti-inflammatory effects of silibinin and thymol when administered in combination to lipopolysaccharide (LPS)-induced RAW264.7 cells. METHODS: RAW264.7 cells were pre-treated with silibinin and thymol individually or in combination for 2 h before LPS stimulation. Cell viability was detected by the MTT assay. Nitric oxide (NO) production was measured by Griess reagent. Reactive oxygen species (ROS) was evaluated by 2',7'-dichlorofluorescein-diacetate. ELISA was used to detect tumour necrosis factor-α (TNF-α), and interleukin-6 (IL-6). Western blot was performed to analyse the protein expression of LPS-induced RAW264.7 cells. RESULTS: We observed a synergistic anti-inflammatory effect of silibinin and thymol when administered in combination to LPS-induced RAW264.7 cells. Silibinin combined with thymol (40 µM and 120 µM respectively, with the molar ratio 1:3) had more potent effects on the inhibition of NO, TNF-α, and IL-6 than those exerted by individual administration of these compounds in LPS-induced RAW264.7 cells. The combination of silibinin and thymol (40 µM and 120 µM respectively, with the molar ratio 1:3) strongly inhibited ROS and cyclooxygenase-2 (COX-2). More importantly, the combination of silibinin and thymol (40 µM and 120 µM respectively, with the molar ratio 1:3) was also successful in inhibiting nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) activities. Our results suggest that the synergistic anti-inflammatory effects of silibinin with thymol were associated with the inhibition of NF-κB and MAPK signalling pathways. CONCLUSION: The combination of silibinin and thymol (40 µM and 120 µM, respectively, with the molar ratio 1:3) could inhibit inflammation by suppressing NF-κB and MAPK signalling pathways in LPS-induced RAW264.7 cells.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , NF-kappa B/metabolism , Silybin/pharmacology , Thymol/pharmacology , Animals , Cyclooxygenase 2/metabolism , Drug Synergism , Inflammation/drug therapy , Inflammation/metabolism , Lipopolysaccharides/pharmacology , Lipopolysaccharides/toxicity , MAP Kinase Signaling System/drug effects , Mice , Mitogen-Activated Protein Kinases/metabolism , Nitric Oxide/metabolism , RAW 264.7 Cells , Reactive Oxygen Species/metabolism , Tumor Necrosis Factor-alpha/metabolismABSTRACT
OBJECTIVE: To study the inhibitive effect of extracts from Scindapsus aureus on alpha-glucosidase and its antioxidant activity. METHODS: The 70% ethanol extracts was extracted by petroleum, ethyl acetate and n-butanol, and the inhibitory activity against alpha-glucosidases and antioxidative effects of each fraction were determined in vitro, and the inhibitory kinetics of ethyl acetate fraction was investigated. RESULTS: The inhibitory activity of ethly acetate fraction against alpha-glucosidase was higher as its IC50 was 43.63 microg/mL. The inhibition kinetics analyzed by Hnewaver-Burk plots showed that ethyl acetate fraction was a competitive type inhibitor, and the inhibition constants for free ennzyme (Ki) was determined to be 21.49 microg/mL. The antioxidative effects of ethly acetate and n-butanol fractions exhibited stronger than that of other fractions, the scavenging ability on DPPH at the concentration of 0.42 mg/mL were 88.5% and 93.6%. Ethly acetate fraction showed scavenging ability on autioxidantor, and the IC50 values was 0.27 mg/mL. CONCLUSION: Ethyld acetate fraction of extract from Scindapsus aureus has potential inhibitroy activity against alpha-glucosidase and antioxidant effects, and n-butanol fraction has great antioxidative effects.
Subject(s)
Antioxidants/pharmacology , Araceae/chemistry , Free Radicals/metabolism , Glycoside Hydrolase Inhibitors , Plant Extracts/pharmacology , Acetates , Antioxidants/isolation & purification , Araceae/growth & development , Ethanol , Inhibitory Concentration 50 , Plant Extracts/isolation & purification , Plants, Medicinal/chemistry , Plants, Medicinal/growth & development , Spectrophotometry, Ultraviolet , alpha-Glucosidases/metabolismABSTRACT
OBJECTIVE: To study the inhibition of extracts from Synotis erythropappa on tyrosinase. METHODS: The 70% ethanol extracts were extracted by petroleum benzine, ethyl acetate and n-butanol, and the inhibitory activities against tyrosinase of every fraction were determined in vitro and the inhibitory kinetics of ethyl acetate and n-butanol fractions were investigated. RESULTS: The four fractions extracted all had inhibitory activities on tyrosinase, inhibitory activities of ethyl acetate and n-butanol fraction were higher. Their IC50 were 57.8, 140 microg/ml for monophenol oxidase activity and 41.2, 59.6 microg/ml for diphenol oxidase activity, respectively. The inhibition kinetics analyzed by Hnewaver-Burk plots showed that ethyl acetate fraction was a competitive type inhibitor, and its Ki was determined to be 19.7 microg/ml. n-butanol fraction was an uncompetitive type inhibitor, and its Ki was determined to be 60.7 microg/ml. CONCLUSION: Ethyl acetate and n-butanol fractions of extracts from Synotis erythropappa show potential inhibitory activity on tyrosinase.