The Adjuvant Effect of Squalene, an Active Ingredient of Functional Foods, on Doxorubicin-Treated Allograft Mice.

Many functional foods or physiologically active ingredients derived from plants and animals are actively being investigated for their role in chronic disease prevention. Squalene (SQ) is found as active ingredient in the functional foods predominantly present in olive oil and shark liver oil. It is known that during chemotherapy anticancer drugs induce inflammation. SQ has been thought to prevent and suppress inflammation; however, there is little direct evidence available. We examined the adjuvant effect of SQ on tumor-transplanted mice along with anticancer drug doxorubicin (DOX). SQ significantly suppressed the DOX-induced increase in prostaglandin E2 (PGE2) concentration (P < 0.05) in plasma of tumor-bearing mice. SQ inhibited the numbers of writhing response (P < 0.05), formalin-induced pain and decreased COX-2 and substance P expression in the tumor tissue compared to control mice and also enhanced the antitumor efficacy of DOX in allograft mice. Thus, SQ reduces inflammation through modulation of PGE2 production indicating its potential as an adjuvant during chemotherapy in tumor-bearing mice.

Pork Loin Treated with High Hydrostatic Pressure as a Food Processing Technology: Subacute Toxicity of the Freeze-Dried Powder and Cytotoxicity of the Methanol Extracts.

High hydrostatic pressure (HP) treatment is used in food processing owing to its sterilization effect. Meat or meat products are sterilized and become tender by HP processing. Therefore, the variety of HP-processed meat products has increased worldwide. However, little is known about the safety of HP-processed meat products. The aim of this study was to determine the effects of HP processing and HP combined with 0.4 M sodium carbonate treatment (HP-Na) on pork loins and to evaluate the subacute toxicity and cytotoxicity of these processing methods. In an in vivo study, we performed 90- and 180-day feeding tests in mice and did not detect any adverse effects in HP-processed and HP-Na-processed pork loins. In addition, we evaluated the cytotoxicity of HP-processed meats, and did not observe any obvious toxicity associated with pork loin extracts in vitro. These results suggest that HP is not associated with risk factors during processing.

The fruit of Acanthopanax senticosus (Rupr. et Maxim.) Harms improves insulin resistance and hepatic lipid accumulation by modulation of liver adenosine monophosphate-activated protein kinase activity and lipogenic gene expression in high-fat diet-fed obese mice.

Obesity-associated insulin resistance is a major risk factor for most metabolic diseases, including dyslipidemia and type 2 diabetes. Acanthopanax senticosus (Rupr. et Maxim.) Harms (Goka) root has been used in traditional Chinese medicine for treatment of diabetes and other conditions; however, little is known about the effects of Goka fruit (GF). Goka fruit is rich in anthocyanin, which has beneficial effects on obesity and insulin resistance via activation of adenosine monophosphate-activated protein kinase (AMPK). We hypothesized that GF can improve obesity-associated insulin resistance. The aim of the present study was to investigate whether GF improves insulin resistance in high-fat diet (HFD)-induced obese mice. High-fat diet mice treated with GF (500 and 1000 mg/kg) for 12 weeks showed an improved glucose tolerance and insulin sensitivity, as well as reduced plasma insulin and liver lipid accumulation. Moreover, GF administration to HFD mice resulted in down-regulation of fatty acid synthase expression and up-regulation of cholesterol 7-alpha-hydroxylase expression in the liver. Notably, AMPK phosphorylation in the liver increased after GF administration. In summary, GF supplementation improved obesity-associated insulin resistance and hepatic lipid accumulation through modulation of AMPK activity and lipid metabolism-associated gene expression.

Squalene Inhibits ATM-Dependent Signaling in γIR-Induced DNA Damage Response through Induction of Wip1 Phosphatase.

Ataxia telangiectasia mutated (ATM) kinase plays a crucial role as a master controller in the cellular DNA damage response. Inhibition of ATM leads to inhibition of the checkpoint signaling pathway. Hence, addition of checkpoint inhibitors to anticancer therapies may be an effective targeting strategy. A recent study reported that Wip1, a protein phosphatase, de-phosphorylates serine 1981 of ATM during the DNA damage response. Squalene has been proposed to complement anticancer therapies such as chemotherapy and radiotherapy; however, there is little mechanistic information supporting this idea. Here, we report the inhibitory effect of squalene on ATM-dependent DNA damage signals. Squalene itself did not affect cell viability and the cell cycle of A549 cells, but it enhanced the cytotoxicity of gamma-irradiation (γIR). The in vitro kinase activity of ATM was not altered by squalene. However, squalene increased Wip1 expression in cells and suppressed ATM activation in γIR-treated cells. Consistent with the potential inhibition of ATM by squalene, IR-induced phosphorylation of ATM effectors such as p53 (Ser15) and Chk1 (Ser317) was inhibited by cell treatment with squalene. Thus, squalene inhibits the ATM-dependent signaling pathway following DNA damage through intracellular induction of Wip1 expression.

Antihyperlipidemic effect of Acanthopanax senticosus (Rupr. et Maxim) Harms leaves in high-fat-diet fed mice.

BACKGROUND: Metabolic syndrome is a major risk factor for a variety of obesity-related diseases. Recently, the effects of functional foods have been investigated on lipid metabolism as a means to reduce lipid content in the blood, liver and adipose tissues associated with carnitine O-palmitoyltransferase (CPT) activity. Acanthopanax senticosus (Rupr. et Maxim) Harms (AS) is a medicinal herb possessing a wide spectra of functions including antioxidant, anti-inflammatory and anti-fatigue actions. Despite much research being focused on the cortical roots of AS, little information is available regarding its leaves, which are also expected to promote human health, for example by improving abnormal lipid metabolism. Here, we explored whether AS leaves affect lipid metabolism in mice fed a high-fat diet. RESULTS: The administration of AS to BALB/c mice fed a high-fat diet significantly decreased plasma triglycerides (TG). CPT activity in the liver of these mice was significantly enhanced by AS treatment. CONCLUSION: These findings indicate that AS leaves have the potential to alleviate increase in plasma TG levels due to high-fat diet intake in mice, possibly by increasing mitochondrial fatty acid ß-oxidation, especially via CPT activation. Consequently, daily intake of AS leaves could promote beneficial health effects including the prevention of metabolic syndrome. © 2015 Society of Chemical Industry.