Effect of Short-Term Oral Administration of Phikud Navakot in Rats.

BACKGROUND: Phikud Navakot (PN), composed of nine herbs and used as a main component of Yahom Navakot, is used in traditional Thai medicine against dizziness and fainting. OBJECTIVE: To investigate the effects of PN on blood pressure, heart rate (HR), and antioxidant properties on male Sprague Dawley rats. MATERIAL AND METHOD: All rats were weighted everyday in the morning, after that, PN (10, 50, 100, 200 and 400 mg/kg BW) were given oroesophageal feeding for seven days. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and HR were measured once per two days. At the end of the experiment, the blood was taken for determination of biochemical and hematological parameters, and lipid peroxidation in serum. The heart was immediately removed for Western blot analysis. RESULTS: SBP DBP and MAP of rats were transiently increased after 1 day of PN (100 mg/kg BW) treatment. Meanwhile, HR did not change throughout the experiment. PN (400 mg/kg BW) significantly increased (p< 0.05) the percentage of neutrophils in blood after 7 days of administration. PN treatment has no effect on biochemical parameters and peroxidation of lipid. In addition, ingestion of PN (100 mg/kg BW) significant increased (p < 0.05) HO-1 expression, but did not change ERK1/2 and Bax/Bcl-2 ratio when compared with the control group. CONCLUSION: The results may possibly support the use of PN for prevention and/or alleviation of cardiovascular disorders, caused by reactive oxygen species. However, long-term treatment of PN has to be further studies.

Tamarind seed coat extract restores reactive oxygen species through attenuation of glutathione level and antioxidant enzyme expression in human skin fibroblasts in response to oxidative stress.

OBJECTIVE: To investigate the role and mechanism of tamarind seed coat extract (TSCE) on normal human skin fibroblast CCD-1064Sk cells under normal and oxidative stress conditions induced by hydrogen peroxide (H2O2). METHODS: Tamarind seed coats were extracted with boiling water and then partitioned with ethyl acetate before the cell analysis. Effect of TSCE on intracellular reactive oxygen species (ROS), glutathione (GSH) level, antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase activity including antioxidant protein expression was investigated. RESULTS: TSCE significantly attenuated intracellular ROS in the absence and presence of H2O2 by increasing GSH level. In the absence of H2O2, TSCE significantly enhanced SOD and catalase activity but did not affected on GPx. Meanwhile, TSCE significantly increased the protein expression of SOD and GPx in H2O2-treated cells. CONCLUSIONS: TSCE exhibited antioxidant activities by scavenging ROS, attenuating GSH level that could protect human skin fibroblast cells from oxidative stress. Our results highlight the antioxidant mechanism of tamarind seed coat through an antioxidant enzyme system, the extract potentially benefits for health food and cosmeceutical application of tamarind seed coat.

Antioxidant and anti-lipid peroxidation activities of Tamarindus indica seed coat in human fibroblast cells.

Antioxidant activity and total phenolic content of tamarind seed coat extracts (TSCEs) were compared between the two extracts using boiling-water (TSCE-W) and 70% ethanol (TSCE-E) for extraction. TSCE-W, consisting of the highest phenolic content, possessed 2,2-diphenyl-1 -picrylhydrazyl (DPPH) radical scavenging and anti-lipid peroxidation activities much higher than TSCE-E and Trolox. Additionally, both TSCEs also exhibited superoxide anion and hydrogen peroxide scavenging activities higher than Trolox and BHA. Anti-lipid peroxidation and cytotoxicity of TSCE-W were also studied in human foreskin fibroblast CCD-1064Sk cells. Cytotoxic effect was not observed when exposed to TSCE-W up to 1 mg/mL for 12-48 h. However, TSCE-W significantly attenuated lipid peroxidation in H202-damaged cells. HPLC analysis showed the presence of (+)-catechin, (-)-epicatechin, and procyanidin B2 in TSCE-W, which could be responsible for antioxidant and anti-lipid peroxidation activities. The results suggest that an inexpensive and simple boiling-water extraction of TSCE-W may provide a valuable natural antioxidant source having anti-lipid peroxidation for health food additives, nutraceuticals as well as cosmeceuticals.