Palmitoyl lactic acid induces adipogenesis and a brown fat-like phenotype in 3T3-L1 preadipocytes.

Brown adipose tissue is specialized to generate heat by dissipating chemical energy and may provide novel strategies for obesity treatment in humans. Recently, advances in understanding the pharmacological and dietary agents that contribute to the browning of white adipose tissue have been made to alleviate obesity by promoting energy expenditure. Krill oil is widely used as a health supplement in humans. In this study, the components from krill oil that promote adipogenesis of 3T3-L1 cells were screened to reveal palmitoyl lactic acid (PLA) as a promoter of adipogenesis. The PLA-induced adipocytes contained large number of small lipid droplets. Moreover, similar to the peroxisome proliferator-activated receptor (PPAR)γ agonists, pioglitazone and rosiglitazone, PLA significantly enhances adipogenesis in the presence of dexamethasone compared with PLA alone. Treatment with PLA causes a brown fat-like phenotype in 3T3-L1 cells by enhanced expression of various brown/beige cell-specific genes, such as PR domain containing 16 (Prdm16) and peroxisome proliferative activated receptor, gamma, coactivator 1 alpha (Pgc1a), as well as adiponectin gene. The expression profile of the brown/beige cell-specific genes induced by PLA was similar to that of the PPARγ agonist in 3T3-L1 cells. Our findings suggest that PLA induces a brown fat-like phenotype and, thus, likely has therapeutic potential in treating obesity.

Potential anti-osteoporotic effects of herbal extracts on osteoclasts, osteoblasts and chondrocytes in vitro.

BACKGROUND: Osteoporosis (OP) is one of the most serious diseases in the modern world, and OP patients frequently suffer from fragility fractures in the hip, spine and wrist, resulting in a limited quality of life. Although bisphosphonates (BPs) are the most effective class of anti-bone-resorptive drugs currently available and the most commonly prescribed for the clinical treatment of OP, they are known to cause serious side effects such as bisphosphonate-related osteonecrosis of the jaw. Novel therapeutic materials that can replace the use of BPs have therefore been developed. METHODS: We commenced an institutional collaborative project in which candidates of herbal extracts were selected from more than 400 bioactive herbal products for their potential therapeutic effects not only in OP, but also in oral and skeletal diseases. In the present study, we report on 3 Chinese medical herbal extracts from the root barks of Melia azedarach, Corydalis turtschaninovii, and Cynanchum atratum. RESULTS: All of these extracts inhibited osteoclast proliferation and induced apoptosis by up-regulation of caspase activity and increase of mitochondrial pro-apoptotic proteins expression. Furthermore, the extracts enhanced differentiation, but did not affect proliferation of both osteoblasts and chondrocytes. The osteo-inducible effect was also observed in cultured primary bone marrow cells. CONCLUSIONS: Although these extracts have been utilized in traditional Chinese medicine for hundreds of years, there are no reports to our knowledge, on their therapeutic effects in OP. In this study, we elucidate the potency of these herbal extracts as novel candidates for OP therapy.

Peach leaf contains multiflorin a as a potent inhibitor of glucose absorption in the small intestine in mice.

Peach leaf extract has anti-hyperglycemic effects on the postprandial blood glucose level in glucose-loaded mice. In our previous study, the mechanism of action was considered to be the inhibition of glucose absorption in the small intestine. To elucidate the active principle in peach leaf, purification of the active compound and a structure determination were performed. With the use of bioassay-guided fractionation using glucose-loaded mice, the acetylated kaempferol glycoside multiflorin A (MFA), a potent inhibitor of glucose absorption from the intestine, was isolated from the MeOH extract of leaf of the edible peach Prunus persica. The structure was identified by HPLC using thiazolizine derivatives and by an analysis of its spectral data. The inhibitory effect of MFA against glucose absorption was demonstrated in the dose dependent manner in mice. However, as the deacetylated analog of MFA, multiflorin B did not show the activity at the in vivo, the activity of MFA was suggested to depend on the acetyl group on the sugar moiety. This is the first report of anti-hyperglycemic activity of MFA in peach leaf extract. MFA may be useful in functional foods or medicines for preventing the postprandial absorption of glucose in hyperglycemia.

Suppressive effect of peach leaf extract on glucose absorption from the small intestine of mice.

The crude extract of peach leaves dose-dependently suppressed the postprandial elevation in the blood glucose level after an oral administration of soluble starch to mice. This study examines the mechanism for this suppressive effect in vivo. An oral carbohydrate-loading test on mice showed that the peach leaf extract suppressed the glucose-induced increase in the blood level of glucose, but without affecting the insulin level. An enteral soluble starch and glucose loading test on mice also showed that the crude extract (1,000 mg/kg) significantly suppressed the postprandial elevation of the blood glucose level and increased the amount of glucose that remained in the intestine to within the same range as that with phloridzin (500 mg/kg), a natural sodium-dependent glucose transporter (SGLT)-specific inhibitor. In contrast, the extract did not suppress the postprandial elevation of the blood triglyceride and cholesterol levels in mice, and did not affect the normal blood glucose level in a feeding test for 21 d. These results reveal that the extract of peach leaves suppressed the postprandial elevation of blood glucose level by inhibiting the absorption of glucose in the small intestine of mice.

Suppressive effects by leaves of the Dypsis lutescens palm on fat accumulation in 3T3-L1 cells and fat absorption in mice.

The methanol extract of Dypsis lutescens leaves showed inhibitory effects on lipase activity in vitro and on triglyceride accumulation in 3T3-L1 pre-adipocytes. Further experiments using the extract on mice demonstrated a suppressive effect on the postprandial elevation of blood triglyceride level and an anti-obesity effect on obese mice induced by a high-fat diet. D. lutescens will accordingly be useful for preventing obesity.

Antiobesity effects of Chinese black tea (Pu-erh tea) extract and gallic acid.

The antiobesity effects of Chinese black tea (Pu-erh tea) and of gallic acid (GA) were investigated using in vitro and in vivo assays. Chinese black tea extract (BTE) and GA inhibited pancreatic lipase activity in a dose-dependent manner in vitro; the IC(inhibitory concentration)(50) values were 101.6 and 9.2 µg/mL, respectively. Black tea extract (50, 100 mg/kg body weight (b.w.)) and GA (15, 45 mg/kg b.w.) significantly suppressed the elevation of blood triglyceride after oral administration of a corn oil emulsion (8 mL oil/kg b.w.) to male ddY mice. Moreover, the antiobesity effects of BTE and GA were also evaluated in a mouse model of diet-induced obesity. Female ddY mice were divided into seven groups; normal diet (ND) group, high fat diet (HFD) group, BTE (0.2% and 0.6% of diets) groups, and GA (0.007%, 0.02% and 0.1% of diets) groups; the experimental groups were fed the test diets for 12 weeks. The BTE 0.6% and GA 0.1% groups showed significant suppression of weight gain. The weight of parametrial adipose tissue was strongly correlated with the body weight. These results suggest that GA contributes to the antiobesity effect of BTE as an active constituent by inhibiting pancreatic lipase activity.

Functional-food constituents in the fruiting bodies of Stropharia rugosoannulata.

Nine compounds (1-9) were isolated from the fruiting bodies of Stropharia rugosoannulata. Compounds 1-5, 8, and 9 suppressed the formation of osteoclast. Compounds 2 and 5 showed anti-fungal activity, and their MIC were 250 µM and 500 µM respectively. Compounds 2-6 showed inhibitory effects on thapsigargin toxicity.

Anti-hyperglycaemic effects of the Japanese red maple Acer pycnanthum and its constituents the ginnalins B and C.

The anti-hyperglycaemic effects of the leaves of Acer pycnanthum K. Koch, and the purification and identification of the active compounds were investigated. Extracts of the leaves showed a potent inhibitory effect on the α-glucosidase in both in vivo and in vitro experiments. The fractionation of the crude extract gave two active compounds, ginnalin B (6-O-galloyl-1,5-anhydro-D-glucitol) and ginnalin C (2-O-galloyl-1,5-anhydro-D-glucitol), by spectroscopic analysis. This is the first report that A. pycnanthum and its constituents may be useful for the prevention or treatment of diabetes mellitus.

Pycnalin, a new α-glucosidase inhibitor from Acer pycnanthum.

A new compound, pycnalin (1), together with four known compounds, ginnalins A (2), B (3), C (4), and 3,6-di-O-galloyl-1,5-anhydro-D-glucitol (3,6-di-GAG) (5), were isolated from Acer pycnanthum. The structure of 1 was determined on the basis of 2D-NMR spectral data and synthesis of 1. Pycnalin (1) is the first 1,5-anhydro-D-mannitol linked to a gallic acid, while compounds 2-5 were 1,5-anhydro-D-glucitol linked to gallic acids. All compounds were tested in vitro for α-glucosidase inhibitory and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities. Pycnalin (1) exhibited moderate α-glucosidase inhibitory activity as well as free radical scavenging activity. Ginnalin A (2) and 3,6-di-GAG (5), which have two galloyl groups, exhibited potent α-glucosidase inhibition, compared to those of other compounds 1, 3, and 4 containing a galloyl group. These results suggest that α-glucosidase inhibition is influenced by the number of galloyl groups.

Combinational Anti-tumor Effects of Chemicals from Paeonia lutea Leaf Extract in Oral Squamous Cell Carcinoma Cells.

AIM: We identified chemical components that exhibited antitumor activity against oral squamous cell carcinoma (OSCC) cells and examined their effective concentrations and additive and/or synergistic effects in combinational usage on the proliferation, apoptosis and cell cycle of OSCC cells. MATERIALS AND METHODS: Using high-performance liquid chromatography, nuclear magnetic resonance spectroscopy and electrospray ionization-mass spectrometry, we identified the main chemical components of the methanol extracts from Paeonia lutea. We investigated the pharmaceutical effects of those components on the proliferation, apoptosis, and cell cycle of an OSCC cell line, SAS, using the tetrazolium salt 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and caspase assays, as well as flow cytometry cell cycle analysis. We also examined the effects of those components on the mitogen-activated protein kinase signal transduction pathway by western blotting. Finally, the effects on normal human epidermal keratinocyte cells were also examined in similar experiments. RESULTS: Three chemicals have been identified in P. lutea leaves using high performance liquid chromatography: gallic acid methyl ester (GAME), pentagalloyl glucose (PGG) and paeoniflorin (PF). Both GAME and PGG significantly suppressed cell proliferation, and their combined effects were synergistic, while the effect of PF was minimal. However, those chemicals did not induce apoptosis. Cell cycle and western blotting analysis showed that the suppressive effects on cell proliferation resulted from G2 arrest and the suppression of phosphorylation of Akt/PKB. No effect was identified on normal human epidermal keratinocyte cells. CONCLUSION: These results indicate that GAME and PGG are the main chemical components of P. lutea leaves that have potential anti-cancer therapeutic effects.

Suppressive effect of Yamato-mana (Brassica rapa L. Oleifera Group) constituent 3-butenyl glucosinolate (gluconapin) on postprandial hypertriglyceridemia in mice.

We examined the bioactivity of Yamato-mana (Brassica rapa L. Oleifera Group) constituent glucosinolates and found that 3-butenyl glucosinolate (gluconapin) decreased the plasma triglyceride gain induced by corn oil administration to mice. However, phenethyl glucosinolate (gluconasturtiin) had little effect. 2-Propenyl glucosinolate (sinigrin) also reduced the plasma triglyceride level, which suggests that alkenyl glucosinolates might be promising agents to prevent postprandial hypertriglyceridemia.

Banana peel extract suppressed prostate gland enlargement in testosterone-treated mice.

A methanol extract of banana peel (BPEx, 200 mg/kg, p.o.) significantly suppressed the regrowth of ventral prostates and seminal vesicles induced by testosterone in castrated mice. Further studies in the androgen-responsive LNCaP human prostate cancer cell line showed that BPEx inhibited dose-dependently testosterone-induced cell growth, while the inhibitory activities of BPEx did not appear against dehydrotestosterone-induced cell growth. These results indicate that methanol extract of banana peel can inhibit 5alpha-reductase and might be useful in the treatment of benign prostate hyperplasia.

Anti-obesity effect on rodents of the traditional Japanese food, tororokombu, shaved Laminaria.

Tororokombu is a traditional Japanese food made from edible kelp. The way to make tororokombu is characterized by shaving kelp very thinly. It was found that tororokombu decreased the serum triglyceride level induced by oil administration to rats and had an anti-obesity effect on obese mice induced by a high-fat diet. These effects were more powerful than those of non-shaved kelp.

Inhibitory effects of benzyl benzoate and its derivatives on angiotensin II-induced hypertension.

Hypertension is a lifestyle-related disease which often leads to serious conditions such as heart disease and cerebral hemorrhage. Angiotensin II (Ang II) plays an important role in regulating cardiovascular homeostasis. Consequently, antagonists that block the interaction of Ang II with its receptors are thought to be effective in the suppression of hypertension. In this study, we searched for plant compounds that had antagonist-like activity toward Ang II receptors. From among 435 plant samples, we found that EtOH extract from the resin of sweet gum Liquidambar styraciflua strongly inhibited Ang II signaling. We isolated benzyl benzoate and benzyl cinnamate from this extract and found that those compounds inhibited the function of Ang II in a dose-dependent manner without cytotoxicity. An in vivo study showed that benzyl benzoate significantly suppressed Ang II-induced hypertension in mice. In addition, we synthesized more than 40 derivatives of benzyl benzoate and found that the meta-methyl and 3-methylbenzyl 2'-nitrobenzoate derivatives showed about 10-fold higher activity than benzyl benzoate itself. Thus, benzyl benzoate, its derivatives, and benzyl cinnamate may be useful for reducing hypertension.

New phospholipase A1-producing bacteria from a marine fish.

Phospholipase A1 is a hydrolytic enzyme that catalyzes the removal of the acyl group from position 1 of glycerophospholipids to form 2-acyl lysophospholipids. Lysophospholipids are used in foods, cosmetics, and pharmaceuticals as surfactants. Novel forms of phospholipase A1 that function at low temperatures are desirable for use in lipophilic systems in food processing. However, there is currently little variety in the available sources of phospholipase A1. Given this situation, we screened the intestinal contents of marine animals for phospholipase A1-producing bacteria. Colonies that formed a halo on K28CP screening medium and that grew in K28 medium were cultured in liquid K28 medium, and the supernatant was retrieved for analysis. Phosphatidylcholine was added to the culture supernatant, and the product of the reaction was analyzed by using TLC. For culture supernatants that were able to generate lysophosphatidylcholine, synthetic phosphatidylcholines were added, and the site of the reaction was determined by analyzing the fatty acid compositions of the lysophosphatidylcholines generated by GLC. A bacterial isolate from a flatfish, which we named HFKI0020, was found to have phospholipase A1 activity at low temperatures. We determined that the isolate HFKI0020 is closely related to Pseudomonas by using 16S rDNA sequence analysis and by characterizing the isolate with respect to its physiologic and biochemical properties. From the intestinal contents of a marine fish, we successfully isolated a bacterium that secretes phospholipase A1 that is active at low temperatures.

Anti-hyperglycemic activity of kiwifruit leaf (Actinidia deliciosa) in mice.

The methanol extract of kiwifruit leaf suppressed the postprandial blood glucose level after an oral administration of soluble starch or sucrose in mice. The mechanism of action is proposed to be due to the alpha-amylase-inhibiting activity in the 90% aqueous methanol fraction and alpha-glucosidase-inhibiting activity in the n-buthanol fraction, based on the results of in vitro experiments.

On-site Direct Detection of Astaxanthin from Salmon Fillet Using Raman Spectroscopy.

A new technology employing Raman spectroscopy is attracting attention as a powerful biochemical technique for the detection of beneficial and functional food nutrients, such as carotenoids and unsaturated fatty acids. This technique allows for the dynamic characterization of food nutrient substances for the rapid determination of food quality. In this study, we attempt to detect and measure astaxanthin from salmon fillets using this technology. The Raman spectra showed specific bands corresponding to the astaxanthin present in salmon and the value of astaxanthin (Raman band, 1518 cm-1) relative to those of protein/lipid (Raman band, 1446 cm-1) in the spectra increased in a dose-dependent manner. A standard curve was constructed by the standard addition method using astaxanthin as the reference standard for its quantification by Raman spectroscopy. The calculation formula was established using the Raman bands typically observed for astaxanthin (i.e., 1518 cm-1). In addition, we examined salmon fillets of different species (Atlantic salmon, coho salmon, and sockeye salmon) and five fillets obtained from the locations (from the head to tail) of an entire Atlantic salmon. Moreover, the sockeye salmon fillet exhibited the highest astaxanthin concentration (14.2 mg/kg), while coho salmon exhibited an intermediate concentration of 7.0 mg/kg. The Raman-based astaxanthin concentration in the five locations of Atlantic salmon was more strongly detected from the fillet closer to the tail. From the results, a rapid, convenient Raman spectroscopic method was developed for the detection of astaxanthin in salmon fillets.

Effects of fenugreek seeds (Trigonella foenum greaecum) extract on endurance capacity in mice.

The present study was designed to determine the effect of fenugreek seed extract (FG) on endurance capacity in male mice aged 4 wk. Mice were given orally either vehicle or FG (150, 300 mg/kg body weight) by stomach intubation for 4 wk. The 300 mg/ kg FG group showed a significant increase in swimming time to exhaustion as compared to the control group. In the FG groups, blood lactate concentration was significantly lower than in the control group. In the control group, plasma non-esterified fatty acid (NEFA) and plasma glucose were decreased by swimming exercise. But in the FG group, NEFA and plasma glucose were significantly increased by swimming. FG treatment also significantly decreased fat accumulation. These results suggest that improvement in swimming endurance by the administration of FG is caused by the increase in utilization of fatty acids as an energy source.

Methanol and Butanol Extracts of Paeonia lutea Leaves Repress Metastasis of Squamous Cell Carcinoma.

Squamous cell carcinoma (SCC) is one of the most common cancers of the head and neck region worldwide and is generally treated surgically in combination with radiotherapy and/or chemotherapy. However, anticancer agents have numerous serious side effects, and alternative, less toxic agents that are effective as chemotherapeutics for SCC are required. The Paeoniaceae family is widely used in traditional Chinese medicine. We examined methanol and butanol extracts of Paeonia lutea (P. lutea) leaves for their potential as an anticancer agent. Both extracts decreased the proliferation of SCC cells, induced apoptotic cell death, and modulated migration, adhesion, chemotaxis, and haptotaxis in an extracellular matrix- (ECM-) dependent manner due to altered expression of several integrin subunits. Subsequently, SCC cells were subcutaneously transplanted into athymic nude mice; the extracts reduced the metastasis of SCC cells but had little effect on the volume of the primary tumor or survival or body weight of the mice. The results suggest that the extracts may hold promise for preventing cancer metastasis.

Effect of omega-3 fatty acid-containing phospholipids on blood catecholamine concentrations in healthy volunteers: a randomized, placebo-controlled, double-blind trial.

OBJECTIVE: We previously reported that administration of fish oil rich in docosahexaenoic acid (DHA) increased the plasma ratio of epinephrine to norepinephrine (NE) at rest in young adults who were under chronic stress and that this effect was achieved mainly through depression of NE. However, not many reports have documented the effects of eicosapentaenoic acid (EPA) and DHA on blood catecholamine levels in healthy humans. Therefore, we performed another intervention study to test their effect on catecholamines with healthy subjects under no chronic stress. METHODS: Twenty-one healthy young adults (15 men and 6 women) were randomly assigned to an omega-3 group (n = 9) or a control group (n = 12) in a double-blind manner. Twenty capsules of shellfish-derived lipids containing 762 mg of EPA plus DHA per day were administered to the omega-3 group for 2 mo. The controls took the same amount of placebo capsules. Fasting blood samples after a 30-min rest with a catheter in a forearm vein were obtained at the start and the end of the study for catecholamine measurements. RESULTS: EPA but not DHA concentrations in red blood cells significantly increased in the omega-3 group compared with the control group (P < 0.001). Plasma NE concentrations were significantly decreased in the omega-3 group (from 1.49 +/- 0.39 nmol/L to 1.05 +/- 0.14 nmol/L) compared with the control group (from 1.12 +/- 0.24 nmol/L to 1.39 +/- 0.32 nmol/L) with analysis of covariance (P < 0.001). The differences remained significant (P = 0.01) even after deletion of three subjects in the omega-3 group who had the highest baseline NE values and one in the control group who had the lowest baseline NE value to nullify a significant baseline differences in NE between groups. CONCLUSION: This study demonstrated that EPA plus DHA supplementation lowered plasma NE concentrations in normal volunteers even at the small dose of 762 mg of EPA plus DHA per day. This effect of EPA plus DHA to lower plasma NE concentrations may be important to understand some of the effects of fish oils on diseases.