Phytochemicals from Tradescantia albiflora Kunth Extracts Reduce Serum Uric Acid Levels in Oxonate-induced Rats.
BACKGROUND
Tradescantia albiflora (TA) Kunth (Commelinaceae) has been used for treating gout and hyperuricemia as folklore remedies in Taiwan. Therefore, it is worthwhile to study the effect of TA extracts on lowering uric acid activity. The hypouricemic effects of TA extracts on potassium oxonate (PO)-induced acute hyperuricemia were investigated for the first time.


METHODS
All treatments at the same volume (1 ml) were orally administered to the abdominal cavity of PO-induced hyperuricemic rats. One milliliter of TA extract in n-hexane (HE), ethyl acetate (EA), n-butanol (BuOH), and water fractions has 0.28, 0.21, 0.28, and 1.03 mg TA, respectively; and the plasma uric acid (PUA) level was measured for a consecutive 4 h after administration.


RESULTS
All four fractions' extracts derived from TA were observed to significantly reduce PUA compared with the PO group. The EA-soluble fraction (TA-EA) exhibited the best xanthine oxidase (XO) inhibitory activity. Following column chromatography, 12 phytochemicals were isolated and identified from the EA fraction. The IC50 values of isolated phytochemicals indicated that bracteanolide A (AR11) showed the remarkable XO inhibitory effect (IC50 value of 76.4 μg/ml). These findings showed that the in vivo hypouricemic effect in hyperuricemic rats was consistent with in vitro XO inhibitory activity, indicating that TA extracts and derived phytochemicals could be potential candidates as hypouricemic agents.


CONCLUSIONS
Tradescantia albiflora extracts possess in vivo hypouricemic action in hyperuricemic ratsT. albiflora extracts exhibited strong inhibitory activity against xanthine oxidase (XO)Butenolide may play an important role in XO inhibitionThe extract bracteanolide A was demonstrated potent XO inhibitory activity in vitro. Abbreviations used: TA: Tradescantia albiflora, PO: potassium oxonate, HE: n-hexane, EA: ethyl acetate, BuOH: n-butanol, PUA: plasma uric acid, XO: xanthine oxidase, MeOH: methanol, IP: intraperitoneal.
School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan; Department of Chinese Internal Medicine, China Medical University Hospital, Taichung, Taiwan.
Wen-Ling
WL
Wang
School of Medicine, Chung Shan Medical University, Taipei, Taiwan; Department of Integrated Chinese and Western Medicine, Chung Shan Medical University Hospital, Taipei, Taiwan; Department of Occupational Therapy, Asia University, Taipei, Taiwan.
Shi-Yuan
SY
Sheu
Department of Agronomy, National Taiwan University, Taipei, Taiwan.
Wen-Dar
WD
Huang
Department of School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan.
Ya-Ling
YL
Chuang
Department of Chemistry, National Taiwan University, Taipei, Taiwan.
Han-Chun
HC
Tseng
Graduate Institute of Biotechnology, Chinese Culture University, Taipei, Taiwan.
Tzann-Shun
TS
Hwang
Department of Chinese Medicine, Buddhist Tzu Chi General Hospital, Taichung Branch, Taiwan; Department of School of Post-Baccalaureate Chinese Medicine, Tzu Chi University, Hualien, Taiwan.
Yuan-Tsung
YT
Fu
Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, China Medical University, Taichung, Taiwan; Department of Biotechnology, Asia University, Taipei, Taiwan.
Yueh-Hsiung
YH
Kuo
School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan; Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan; Department of Biomedical Informatics, Asia University, Taipei, Taiwan.
Chun-Hsu
CH
Yao
Department of School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan; Department of Post-Baccalaureate Veterinary Medicine, Asia University, Taipei, Taiwan.
Tzong-Fu
TF
Kuo
Hyperuricemia; Tradescantia albiflora Kunth; uric acid; xanthine oxidase