Anti-Diabetic Potential of Sargassum horneri and Ulva australis Extracts In Vitro and In Vivo.

Sargassum horneri (SH) and Ulva australis (UA) are marine waste resources that cause environmental and economic problems when entering or multiplying the coastal waters of Jeju Island. We analyzed their anti-diabetic efficacy to assess their reusability as functional additives. The alpha-glucosidase inhibitory activity of SH and UA extracts was confirmed, and the effect of UA extract was higher than that of SH. After the induction of insulin-resistant HepG2 cells, the effects of the two marine extracts on oxidative stress, intracellular glucose uptake, and glycogen content were compared to the positive control, metformin. Treatment of insulin-resistant HepG2 cells with SH and UA resulted in a concentration-dependent decrease in oxidative stress and increased intracellular glucose uptake and glycogen content. Moreover, SH and UA treatment upregulated the expression of IRS-1, AKT, and GLUT4, which are suppressed in insulin resistance, to a similar degree to metformin, and suppressed the expression of FoxO1, PEPCK involved in gluconeogenesis, and GSK-3ß involved in glycogen metabolism. The oral administration of these extracts to rats with streptozotocin-induced diabetes led to a higher weight gain than that in the diabetic group. Insulin resistance and oral glucose tolerance are alleviated by the regulation of blood glucose. Thus, the SH and UA extracts may be used in the development of therapeutic agents or supplements to improve insulin resistance.

Profiles of Essential Oils and Correlations with Phenolic Acids and Primary Metabolites in Flower Buds of Magnolia heptapeta and Magnolia denudata var. purpurascens.

Magnolia flower buds are a source of herbal medicines with various active compounds. In this study, differences in the distribution and abundance of major essential oils, phenolic acids, and primary metabolites between white flower buds of Magnolia heptapeta and violet flower buds of Magnolia denudata var. purpurascens were characterised. A multivariate analysis revealed clear separation between the white and violet flower buds with respect to primary and secondary metabolites closely related to metabolic systems. White flower buds contained large amounts of monoterpene hydrocarbons (MH), phenolic acids, aromatic amino acids, and monosaccharides, related to the production of isoprenes, as MH precursors, and the activity of MH synthase. However, concentrations of ß-myrcene, a major MH compound, were higher in violet flower buds than in white flower buds, possibly due to higher threonine levels and low acidic conditions induced by comparatively low levels of some organic acids. Moreover, levels of stress-related metabolites, such as oxygenated monoterpenes, proline, and glutamic acid, were higher in violet flower buds than in white flower buds. Our results support the feasibility of metabolic profiling for the identification of phytochemical differences and improve our understanding of the correlated biological pathways for primary and secondary metabolites.

Quercetin Suppresses CYR61-Mediated Multidrug Resistance in Human Gastric Adenocarcinoma AGS Cells.

Cysteine-rich angiogenic inducer 61 (CYR61) is an extracellular matrix-associated protein involved in survival, tumorigenesis, and drug resistance. Therefore, we examined the effects of flavones against CYR61-overexpressing human gastric adenocarcinoma AGS (AGS-cyr61) cells, which show remarkable resistance to 5-fluorouracil (5-FU), adriamycin (ADR), tamoxifen (TAM), paclitaxel (PAC), and docetaxel (DOC). Among the tested flavones, quercetin had the lowest 50% inhibitory concentration (IC50) and significantly reduced the viability of AGS-cyr61 cells compared with AGS cells. Quercetin: (1) reduced multidrug resistance-associated protein 1 and nuclear factor (NF)-kappa B p65 subunit levels; (2) reversed multidrug resistance (MDR); (3) inhibited colony formation and induced caspase-dependent apoptosis; and (4) suppressed migration and down-regulated epithelial-mesenchymal transition-related proteins in AGS-cyr61. Moreover, AGS-cyr61 cells treated with quercetin concentrations close to the IC50 and simultaneously treated with 5-FU or ADR in the sub-lethal range showed strong synergism between quercetin and these two drugs. These findings indicate that CYR61 is a potential regulator of drug resistance and that quercetin may be a novel agent for improving the efficacy of anticancer drugs in AGS-cyr61 cells.

Metabolomics Reveals Rubiadin Accumulation and the Effects of Methyl Jasmonate Elicitation in Damnacanthus major Calli.

Callus suspension techniques have been considered attractive for improving bioactive metabolite productivity; methyl jasmonate (MeJA) is a widely used elicitor for stimulating synthetic pathways. In this study, a multivariate analysis-based metabolomics approach was employed to investigate the primary and specialized metabolites in the leaves, unelicited calli, and 100 or 200 µM MeJA elicited calli of Damnacanthus major. Rubiadin, a powerful anthraquinone with various therapeutic properties, was only identified in D. major calli, accumulating in a MeJA elicitation concentration-dependent manner. Callus cultures also contained high levels of amino acids, sugars, and phenolic compounds, indicating energy metabolism and metabolic adaptation responses for proliferation and stabilization. Regarding MeJA application, elicited calli contained higher amounts of quinic acid, kaempferol, and glucose with lower amounts of sucrose and raffinose than those in the unelicited control, which were closely related to protective mechanisms against MeJA. Moreover, excessive elicitation increased the asparagine, fructose, and raffinose levels and decreased the glucose and sucrose levels, which was ascribed to increased activation of the aminoacyl-tRNA biosynthesis pathway and wider utilization of glucose than of fructose after sucrose degradation. These results will be useful for optimizing plant cell culture techniques to achieve high production rates for valuable specialized metabolites.

Immature Persimmon (Diospyros kaki Thunb.) Ethanol Extract Ameliorates High-Fat Diet-Induced Obesity by Modulating Lipid Metabolism.

In this study, immature persimmon (Diospyros kaki Thunb.) ethanol extract was administered to an obese animal model fed a high-fat diet to measure weight change, adipose tissue weight, serum lipid level, and expression level of adipose-related genes to evaluate its efficacy. Administration of D. kaki ethanol extract (DKE) (100 and 500 mg/kg/d) decreased the body weight gain, adipose tissue weight, and serum triglyceride levels in mice fed a high-fat diet. Furthermore, it improved the leptin and adiponectin levels in the blood as well as gene expression in the liver. It also inhibited the expression of sterol regulatory element-binding protein-1c, inhibiting the production of triglyceride biosynthetic enzyme fatty acid synthesis and acetyl-CoA carboxylase, and decreased the expressions of peroxisome proliferator-activated receptor γ and CCAAT/enhancer-binding proteins that induce adipocyte differentiation. Therefore, these data suggest that DKE exerts beneficial effects on high-fat diet-induced obesity by modulating lipid metabolism in mice fed a high-fat diet.

Antioxidant activity of banana flesh and antiproliferative effect on breast and pancreatic cancer cells.

Bananas, one of the most widely consumed fruits worldwide, are a rich source of valuable phytochemicals. In this study, the antioxidant and the anticancer potential of banana flesh was investigated. Of the four kinds of banana flesh extracts, the hexane extract (HE) had the highest total polyphenol content (2.54 ± 0.60 mg GAE/g) and total flavonoid content (1.69 ± 0.34 mg RE/g), followed by the chloroform fraction, total ethanol extract, and ethanol fraction. HE was found to exert a strong radical scavenging activity on 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonicacid) (ABTS•) free radicals. According to the IC50 values in various cancer cell lines, HE was found to possess the greatest cell growth inhibitory potential in human pancreatic cancer PANC-1 cells and human triple-negative breast cancer MDA-MB-231 cells. HE induced apoptosis in PANC-1 and MDA-MB-231 cells, as evidenced by the appearance of condensation of chromatin, proteolytic activation of caspase-3 and 7, and increase in the level of the cleaved form of poly (ADP-ribose) polymerase protein. Gas chromatography mass spectrometry (GC-MS) analysis of HE identified several anticancer compounds including palmitic acid, linoleic acid, oleic acid, campesterol, stigmasterol, and γ-sitosterol, supporting the anticancer potential of HE. Our investigation provides a rationale for the use of banana flesh to minimize the risk of cancer-like diseases.

Extracts of Citrus Juice Processing Wastes Induce Weight Gain and Decrease Serum Glucose in Sprague-Dawley Rats.

In this study, the safety and functionality of using citrus juice processing waste (CJPW) was confirmed. Large quantities of CJPW are generated on Jeju Island and cause environmental problems. CJPW extract (2,000 mg/kg) was administered intragastrically to male and female Sprague-Dawley (SD) rats for 14 days and the rats were analyzed. No general signs of toxicity were observed in SD rats administered CJPW extract. Feed intake did not differ between experimental and control animals. However, male and female rats administered CJPW extract had greater weight gain (102.9±5.53% and 114.15±6.89%, respectively) compared with the control animals. Higher weight gain was found in male and female experimental animals, but the difference was only significant in female animals. Serum analyses indicated that total protein and albumin, indicators of nutritional status, were significantly increased in animals administered CJPW. Further, serum glucose values were lower in male and female rats treated with CJPW (91.6±9.02% and 69.9±4.11%, respectively) compared with the controls; again, the difference was significant only for female animals. From the results of this study, CJPW can be considered as a safe material that does not induce toxicity in experimental animals. Therefore, CJPW is a potential raw material that can be used as a supplement in animal feed to help improve weight gain and achieve serum glucose con-trol.

Clinical Evidence of Effects of Green Mandarin (Putgyul) Extract on Skin Aging: A Randomized, Double Blind, Placebo-Controlled Study.

Green mandarins are widely consumed unripe as mandarin oranges (Citrus unshiu Marcov.), which exhibit anti-inflammatory and anti-wrinkle effects by inhibiting the production of inflammatory cytokines and matrix metalloproteinase. A randomized, double-blind, placebo-controlled clinical study was performed to verify the skin improvement efficacy and safety of green mandarin extract (PTE). For the standardization of PTE, narirutin was set as a marker compound, and PTE with a constant narirutin content was prepared for the study. After randomizing subjects with periorbital wrinkles, they were orally administered PTE (300 mg/day) or a placebo for 12 weeks. Periorbital wrinkles were measured using PRIMOSCR SF. Skin elasticity, moisture content, transepidermal water loss, and gloss were also measured. In the study results, the depth, volume, and skin roughness of the periorbital wrinkles were significantly improved compared to the control group (p = 0.011, 0.009, and 0.004, respectively). The survey confirmed that the skin condition improved after PTE consumption for 12 weeks. No adverse reactions associated with PTE were observed during the study period. Thus, the results demonstrate that PTE effectively improves UV-induced skin wrinkles. Therefore, it is considered that PTE has sufficient value as a functional food ingredient that can prevent skin aging.

Proliferation and Metabolic Profiling of Cynanchum wilfordii Adventitious Roots Using Explants from Different Cultivation Methods.

Cynanchum wilfordii root is used in traditional herbal medicine owing to its various pharmacological activities. However, C. wilfordii roots are misused owing to their morphological similarities with C. auriculatum. Adventitious root (AR) culture can prevent such misuse, and the selection of plant materials is an important procedure for producing high-quality ARs. This study aimed to compare the proliferation and metabolic profiles of C. wilfordii ARs in two types of explants from different cultivation methods (either cultivated in open field (ECF) or cultivated on a heap of C. wilfordii (ECH)). After 4 weeks of culture, the proliferation rate and number and length of secondary ARs were determined, and 3/4 Murashige and Skoog (MS) salt medium, 4.92 µM indole-3-butyric acid (IBA), and 5% sucrose were suggested as the best proliferation conditions for ARs originating from both ECF and ECH. Through metabolic profiling, ARs from ECH were found to show higher accumulation patterns for flavonoids, polysaccharides, hydroxyacetophenones, aromatic amino acids, and mono-unsaturated fatty acids, which were ascribed to the activation of flavonoid biosynthesis, the phenylpropanoid pathway, and fatty acid desaturase, stimulated by abiotic stresses. In contrast, ARs from ECF had higher levels of TCA cycle intermediates, amino acids in the aspartate-glutamate pathway, and saturated and polyunsaturated fatty acids, indicating energy metabolism and plant development. Overall, the current study provided information on the optimal conditions for inducing C. wilfordii ARs with higher amounts of bioactive compounds.

Effects of Sargassum horneri and Ulva australis Extracts on Body Weight and Serum Glucose Levels of Sprague-Dawley Rats.

This study investigated the safety and functionality of a functional additive for humans and animals from Sargassum horneri (SH) and Ulva australis (UA) waste for recycling marine refuse generated in large quantities in Jeju. Sprague-Dawley rats were orally administered functional additives at 2,000 mg/kg to assess 14-day repeated dose toxicity of the two extracts. For female rats, weight gain after administration of SH was 66.2±18.8% vs. controls. Male rats administered UA showed weight gain of 92.3±8.0% vs. controls. SH and UA significantly decreased serum glucose levels in male rats compared with controls (79.8±11.10% and 76.1±9.67%, respectively). Similarly, significant decrease in serum glucose levels were shown for female rats after administration of SH and UA (79.2±1.58% and 82.8±3.21%, respectively). Furthermore, rats showed significant differences vs. controls in several serological parameters after receiving extracts, however results remained within the normal range. Thus, the SH and UA extracts were considered safe substances that may be used as functional additives to help reduce body weight and serum glucose.

Supercritical Fluid Extraction of Citrus iyo Hort. ex Tanaka Pericarp Inhibits Growth and Induces Apoptosis Through Abrogation of STAT3 Regulated Gene Products in Human Prostate Cancer Xenograft Mouse Model.

Activation of signal transducer and activator of transcription 3 (STAT3) is well known to play a major role in the cell growth, survival, proliferation, metastasis, and angiogenesis of various cancer cells. Most of the citrus species offer large quantities of phytochemicals that have beneficial effects attributed to their chemical components. Our study was carried out to evaluate the anticancer effects of the pericarp of Iyokan ( Citrus iyo Hort. ex Tanaka), locally known as yeagam in Korea, through modulation of the STAT3 signaling pathway in both tumor cells and a nude mice model. The effect of supercritical extracts of yeagam peel (SEYG) on STAT3 activation, associated protein kinases, STAT3-regulated gene products, cellular proliferation, and apoptosis was examined. The in vivo effect of SEYG on the growth of DU145 human prostate xenograft tumors in athymic nu/nu male mice was also investigated. We found SEYG exerted substantial inhibitory effect on STAT3 activation in human prostate cancer DU145 cells as compared to other tumor cells analyzed. SEYG inhibited proliferation and downregulated the expression of various STAT3-regulated gene products such as bcl-2, bcl-xL, survivin, IAP-1/2, cyclin D1, cyclin E, COX-2, VEGF, and MMP-9. This correlated with an increase in apoptosis as indicated by an increase in the expression of p53 and p21 proteins, the sub-G1 arrest, and caspase-3-induced PARP cleavage. When administered intraperitoneally, SEYG reduced the growth of DU145 human prostate xenograft tumors through downmodulation of STAT3 activation in athymic nu/nu male mice. Overall, these results suggest that SEYG extract has the potential source of STAT3 inhibitors that may have a potential in chemoprevention of human prostate cancer cells.