Anti-stress activity of Sargassum polycystum extracts using a cold restraint stress model

Association of Seaweed Consumption with Metabolic Syndrome and Its Components: Findings from the Korean Genome and Epidemiology Study

This study aimed to investigate the association between seaweed consumption and the odds of developing metabolic syndrome in middle-aged and elderly Koreans. The study included 5777 adults aged 40-69 years from 2001 to 2002 in the Ansan and Ansung cohorts of the Korean Genome and Epidemiology Study. Data on the consumption of seaweed, including laver and kelp/sea mustard, were obtained using a semiquantitative food frequency questionnaire. Multivariable logistic regression models were used to assess the association between seaweed consumption and the odds of developing metabolic syndrome and its components. Women in the highest tertile of laver consumption had lower odds of developing metabolic syndrome than those in the lowest tertile (adjusted odds ratio [AOR]: 0.70; 95% confidence interval [CI]: 0.54-0.92). Both men and women in the highest tertile of laver consumption had lower odds of abdominal obesity than those in the lowest tertile (AOR: 0.64, 95% CI: 0.42-0.98 for men; AOR: 0.53, 95% CI: 0.39-0.72 for women). These findings suggest that laver consumption is inversely associated with the odds of developing metabolic syndrome and abdominal obesity in Korean adults.

Effects of In Vitro Digestion on Anti-α-Amylase and Cytotoxic Potentials of Sargassum spp

This is the first study to examine the effects of in vitro digestion on biological activities of Sargassum spp., a broadly known brown seaweed for therapeutic potential. Three fractions (F1-F3) were obtained from hexane extract by column chromatography. Under in vitro simulated digestion, the anti-α-amylase capacity of F1 in oral and intestinal phases increases, while it significantly decreases in the gastric phase. The α-amylase inhibition of F2 promotes throughout all digestive stages while the activity of F3 significantly reduces. The cytotoxic activity of F1 against U266 cell-line accelerates over the oral, gastric, and intestinal stages. The fractions F2 and F3 exhibited the declined cytotoxic potentialities in oral and gastric phases, but they were strengthened under intestinal condition. Palmitic acid and fucosterol may play an active role in antidiabetic and cytotoxic activity against multiple myeloma U266 cell line of Sargassum spp. However, the involvement of other phytochemicals in the seaweed should be further investigated.

Sargassum hystrix as a Source of Functional Food to Improve Blood Biochemistry Profiles of Rats under Stress

This study was conducted to determine the influence of Sargassum hystrix powder (SHP) as an alternative source of functional food for treating in vivo stress by measuring levels of glucose, triacylglycerol, total cholesterol, and cortisol, and liver histopathology. Wistar rats aged 3 months and weighing 150~200 g were divided into 7 groups: normal control, fasting control, negative control (stress without adaptogen), and 4 experimental conditions (stress+0.18 mg/kg diazepam, stress+450 mg/kg pellet, stress+mixture of pellet with SHP 450 mg/kg, and stress+450 mg/kg of SHP). Intake of liquids and and body weight were measured daily. Blood samples were collected on day 0 (baseline), day 5, and day 10 to analyze levels of glucose, triacylglycerol, cholesterol, and cortisol. On day 10, rats were euthanized and livers were collected to observe the severity of inflammation. The results indicated that rats receiving SHP 450 mg/kg and the mixture of pellet with SHP 450 mg/kg showed a similar ability as those receiving diazepam 0.18 mg/kg to cope with stress, indicated by an improvement in all blood biochemistry parameters. Supplementation with SHP 450 mg/kg can be used as an alternative source of functional food for overcoming oxidative stress, as indicated by its ability to improve levels of blood glucose, triacylglycerol, total cholesterol, and cortisol, and to improve liver histology by decreasing severity of liver inflammation.

Antistress Effects of San-Huang-Xie-Xin Decoction on Restraint-Stressed Mice Revealed by 1H NMR-Based Metabolomics and Biochemistry Analysis

San-Huang-Xie-Xin decoction (SHXXD), composed of Rhei Radix et Rhizoma, Coptidis Rhizoma, and Scutellariae Radix, is a representative antipyretic and detoxifying prescription in traditional Chinese medicine. In this study, we investigated the antistress effects and underlying mechanisms of San-Huang-Xie-Xin decoction (SHXXD) on restraint-stressed mice by ¹H NMR-based metabolomics combined with biochemistry assay. A total of 48 male mice (5 weeks old, 18-22 g) were divided randomly into 6 groups (n = 8), including the normal group, restraint-stressed group, vitamin C group (positive drug, 17 mg/kg), and 3-dosage groups of SHXXD (200, 400, and 800 mg/kg). The stress model was induced by restraining mice in a polypropylene centrifuge tube for 6 h every day. The rotarod test was performed, and several biochemical indicators were measured. Moreover, other 24 animals were divided into 3 groups (n = 8) including the normal group, restraint-stressed group, and SHXXD group (800 mg/kg) for ¹H NMR-based metabolomics analysis. Our results showed that SHXXD significantly increased the rotarod time, thymus index, spleen index, and the levels of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and interleukin- (IL-) 2, but decreased the levels of malondialdehyde (MDA), IL-1β, tumor necrosis factor- (TNF-) α, corticosterone (CORT), and adrenocorticotropic hormone (ACTH) in restraint-stressed mice. Moreover, the contents of eight endogenous metabolites that were changed by restraint stress were significantly reversed by SHXXD. The results of both metabolomics and biochemical analysis indicated that SHXXD (800 mg/kg, p.o.) could improve the biochemical changes and metabolic disorders in restraint-stressed mice by antioxidation and anti-inflammation, enhancing the body's immune function and restoring several disturbed metabolic pathways (i.e., lipid metabolism, glycolysis and gluconeogenesis, inflammatory injury, and energy metabolism). Taken together, these results indicated that SHXXD has a potential antistress effect in restraint-stressed mice and could be considered as a candidate drug for stress-related disorders.

Antidiabetic Activity of Sargassum hystrix Extracts in Streptozotocin-Induced Diabetic Rats

The objective of this research was to determine the potential effects of Sargassum hystrix extracts (SHE) on the glucose levels, lipid profile, and pancreas of streptozotocin (STZ)-induced diabetic rats. SHE at 200, 300, and 400 mg/kg was administered orally to STZ-induced diabetic rats once daily for 15 days. Glucose levels, lipid profile, and weight of rats were measured in the normal state and on the 15th day. The histology of the pancreas was observed on the 15th day. The results showed that the preprandial and postprandial glucose levels in the group treated with SHE at 300 mg/kg were significantly reduced compared with those of the diabetes group. Additionally, the levels of triglycerides and cholesterol in the 300 mg/kg SHE group were significantly different from those in the diabetes group. However, the levels of high-density lipoprotein cholesterol and low-density lipoprotein cholesterol across the treatment groups did not have significant differences. Necrosis was found in all STZ-induced rats. SHE at a dose of 300 mg/kg had the best capability to lower the levels of preprandial and postprandial glucose and to prevent necrosis in diabetic rats.