Effect of onion peel extract on endothelial function and endothelial progenitor cells in overweight and obese individuals.

OBJECTIVES: Acute or chronic intake of polyphenol-rich foods has been reported to improve endothelial function. Quercetin, found abundantly in onion, is a potent antioxidant flavonoid. The aim of this study was to investigate whether consumption of onion peel extract (OPE) improves endothelial function in healthy overweight and obese individuals. METHODS: This was a randomized double-blind, placebo-controlled study. Seventy-two healthy overweight and obese participants were randomly assigned to receive a red, soft capsule of OPE (100 mg quercetin/d, 50 mg quercetin twice daily; n = 36 participants) or an identical placebo capsule (n = 36) for 12 wk. Endothelial function, defined by flow-mediated dilation (FMD), circulating endothelial progenitor cells (EPCs) by flow cytometry, and laboratory test were determined at baseline and after treatment. RESULTS: Baseline characteristics and laboratory findings did not significantly differ between the two groups. Compared with baseline values, the OPE group showed significantly improved FMD at 12 wk (from 12.5 ± 5.2 to 15.2 ± 6.1; P = 0.002), whereas the placebo group showed no difference. Nitroglycerin-mediated dilation did not change in either group. EPC counts (44.2 ± 25.6 versus 52.3 ± 18.6; P = 0.005) and the percentage of EPCs were significantly increased in the OPE group. When FMD was divided into quartiles, rate of patients with endothelial dysfunction defined as lowest quartile (cutoff value, 8.6%) of FMD improved from 26% to 9% by OPE. CONCLUSION: Medium-term administration of OPE an improvement in FMD and circulating EPCs.

Effects of electroacupuncture on endothelial function and circulating endothelial progenitor cells in patients with cerebral infarction.

This study evaluated the effects of electroacupuncture (EA) on endothelial function and endothelial progenitor cells (EPC) in patients with cerebral infarction. In a randomized, placebo-controlled, crossover study, 20 patients with cerebral infarction were randomized into two treatment groups: EA or placebo. Before and after each intervention, pulse amplitude tonometry (PAT) was used to assess endothelial function and peripheral blood was analyzed for the number of EPCs. Circulating EPCs were quantified by flow cytometry as CD45(low) CD34(+) KDR2(+) cells. Plasma vascular endothelial growth factor (VEGF) and interleukin (IL)-10 levels were measured. Seven days later, crossover was performed on each group, with each group receiving the other treatment using the same protocol. The PAT hyperemia ratio ranged from 1.57 ± 0.41 to 2.04 ± 0.51 after EA, representing a significant improvement (P = 0.002); however, there was no improvement in the placebo group (P = 0.48). Circulating EPCs, as measured by flow cytometry, increased to 110.6 ± 74.3/100 µL in the EA group (P = 0.001) but did not change in the placebo group (45.9 ± 35.3/100 µL, P = 0.08). The increases in the number of EPCs and the PAT ratio after treatment were correlated (r = 0.78, P < 0.001). Plasma VEGF levels increased with EA compared to baseline (261.2 ± 34.0 vs 334.9 ± 80.5 pg/mL, P = 0.003). The number of circulating EPCs was positively correlated with plasma levels of VEGF (r = 0.50, P = 0.02). In conclusion, EA induced improvement of EPC levels and the PAT ratio in patients with cerebral infarction.

Additional Effects of Back-Shu Electroacupuncture and Moxibustion in Cardioprotection of Rat Ischemia-Reperfusion Injury.

Many preclinical studies show that electroacupuncture (EA) on PC6 and ST36 can reduce infarct size after ischemia-reperfusion (IR) injury. Yet studies to enhance the treatment effect size are limited. The purpose of this study was to explore whether EA has additional myocardial protective effects on an ischemia-reperfusion (IR) injury rat model when back-shu EA and moxibustion are added. SD rats were divided into several groups and treated with either EA only, EA + back-shu EA (B), or EA + B + moxibustion (M) for 5 consecutive days. Transthoracic echocardiography and molecular and immunohistochemical evaluations were performed. It was found that although myocardial infarct areas were significantly lower and cardiac function was also significantly preserved in the three treatment groups compared to the placebo group, there were no additional differences between the three treatment groups. In addition, HSP20 and HSP27 were expressed significantly more in the treatment groups. The results suggest that adding several treatments does not necessarily increase protection. Our study corroborates previous findings that more treatment, such as prolonging EA duration or increasing EA intensity, does not always lead to better results. Other methods of increasing treatment effect size should be explored.

Titrated extract of Centella asiatica provides a UVB protective effect by altering microRNA expression profiles in human dermal fibroblasts.

The titrated extract of Centella asiatica (TECA) is a reconstituted mixture comprising of asiatic acid, madecassic acid, asiaticoside and madecassoside, and is used as a therapeutic agent in wound healing and also as an anti-microbial, anticancer and anti-aging agent. Although these properties and the associated cell signaling pathways have been elucidated, the cellular mechanism of anti-photoaging upon ultraviolet (UV) exposure in normal human dermal fibroblasts (NHDFs) remains unknown. In this study, we investigated the photoprotective role of TECA via microRNA (miRNA) expression profiling analysis. Low dose of TECA did not exhibit toxicity and showed a protective effect against UVB irradiation in NDHFs. miRNA microarray experiments revealed that specific miRNAs were altered by TECA stimulation in UVB-irradiated NHDFs. Functional bioinformatic analysis showed that the putative target genes of the altered miRNAs were associated with the positive regulation of cell proliferation, anti-apoptosis, small GTPase- and Ras-mediated signal transduction and activation of MAPKK. Therefore, these results suggest that TECA may serve as a potential natural chemoprotective agent against UVB-mediated damage in NHDFs through changes in the expression of specific miRNAs.