Anti-Glycation Effects of Pomegranate (Punica granatum L.) Fruit Extract and Its Components in Vivo and in Vitro.

Accumulation of advanced glycation end products (AGEs) leads to various diseases such as diabetic complications and arteriosclerosis. In this study, we examined the effect of pomegranate fruit extract (PFE) and its constituent polyphenols on AGE formation in vivo and in vitro. PFE, fed with a high-fat and high-sucrose (HFS) diet to KK-A(y) mice, significantly reduced glycation products such as glycoalbumin (22.0 ± 2.4%), hemoglobin A1c (5.84 ± 0.23%), and serum AGEs (8.22 ± 0.17 µg/mL), as compared to a control HFS group (30.6 ± 2.6%, 7.45 ± 0.12%, and 9.55 ± 0.17 µg/mL, respectively, P < 0.05). In antiglycation assays, PFE, punicalin, punicalagin, ellagic acid, and gallic acid suppressed the formation of AGEs from bovine serum albumin and sugars. In this study, we discuss the mechanism of the antiglycation effects of PFE and its components in vivo and in vitro.

Daily intake of rosehip extract decreases abdominal visceral fat in preobese subjects: a randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND: Obesity has become a great problem all over the world. We repeatedly screened to find an effective food to treat obesity and discovered that rosehip extract shows potent anti-obesity effects. Investigations in mice have demonstrated that rosehip extract inhibits body weight gain and decreases visceral fat. Thus, the present study examined the effect of rosehip extract on human body fat in preobese subjects. METHODS: We conducted a 12-week, single-center, double-blind, randomized, placebo-controlled study of 32 subjects who had a body mass index of ≥25 but <30. The subjects were assigned to two random groups, and they received one tablet of placebo or rosehip that contained 100 mg of rosehip extract once each day for 12 weeks with no dietary intervention. Abdominal fat area and body fat percent were measured as primary outcomes. The other outcomes were body weight and body mass index. RESULTS: Abdominal total fat area, abdominal visceral fat area, body weight, and body mass index decreased significantly in the rosehip group at week 12 compared with their baseline levels (P<0.01) after receiving the rosehip tablet intake, and the decreases in these parameters were significantly higher when compared with those in the placebo group. Additionally, body fat percent tended to decrease compared with the placebo group and their baseline level. Moreover, the abdominal subcutaneous fat area was significantly lower in the rosehip group than in the placebo group at week 12 after the initiation of intake (P<0.05). In addition, there were no abnormalities, subjective symptoms, and findings that may indicate clinical problems during the study period. CONCLUSION: These results suggest that rosehip extract may be a good candidate food material for preventing obesity.

Rosehip Extract Inhibits Lipid Accumulation in White Adipose Tissue by Suppressing the Expression of Peroxisome Proliferator-activated Receptor Gamma.

Recent studies have shown that Rosa canina L. and tiliroside, the principal constituent of its seeds, exhibit anti-obesity and anti-diabetic activities via enhancement of fatty acid oxidation in the liver and skeletal muscle. However, the effects of rosehip, the fruit of this plant, extract (RHE), or tiliroside on lipid accumulation in adipocytes have not been analyzed. We investigated the effects of RHE and tiliroside on lipid accumulation and protein expression of key transcription factors in both in vitro and in vivo models. RHE and tiliroside inhibited lipid accumulation in a dose-dependent manner in 3T3-L1 cells. We also analyzed the inhibitory effect of RHE on white adipose tissue (WAT) in high-fat diet (HFD)-induced obesity mice model. Male C57BL/6J mice were fed HFD or HFD supplemented with 1% RHE (HFDRH) for 8 weeks. The HFDRH-fed group gained less body weight and had less visceral fat than the HFD-fed group. Liver weight was significantly lower in the HFDRH-fed group and total hepatic lipid and triglyceride (TG) content was also reduced. A significant reduction in the expression of peroxisome proliferator-activated receptor gamma (PPARγ) was observed in epididymal fat in the HFDRH-fed group, in comparison with controls, through Western blotting. These results suggest that downregulation of PPARγ expression is involved, at least in part, in the suppressive effect of RHE on lipid accumulation in WAT.