Anti-Hypercholesterolemia Effects of Edible Seaweed Extracts and Metabolomic Changes in Hep-G2 and Caco-2 Cell Lines.

Hypercholesterolemia is a major risk for the development of cardiovascular diseases (CVDs), the main cause of mortality worldwide, and it is characterized by high levels of circulating cholesterol. The drugs currently available for hypercholesterolemia control have several side effects, so it is necessary to develop new effective and safer therapies. Seaweeds serve as sources of several bioactive compounds with claimed beneficial effects. Eisenia bicyclis (Aramé) and Porphyra tenera (Nori) are edible seaweeds that were previously recognized as rich in bioactive compounds. In the present study, we aim to evaluate the anti-hypercholesterolemia effect of these two seaweed extracts and their health potential. Both extracts, but more efficiently Aramé extract, have liver 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) inhibitory activity as well as the capability to reduce approximately 30% of cholesterol permeation through human Caco-2 cells by simulating the intestinal lining, which is a target for hypercholesterolemia treatments. An untargeted metabolomic assay on human intestinal Caco-2 and liver Hep-G2 cell lines exposed to Aramé and Nori extracts revealed changes in the cells' metabolism, indicating the extracts' health beneficial effects. The metabolic pathways affected by exposure to both extracts were associated with lipid metabolism, such as phospholipids, and fatty acid metabolism, amino acid pathways, cofactors, vitamins, and cellular respiration metabolism. The effects were more profound in Aramé-treated cells, but they were also observed in Nori-exposed cells. The metabolite modifications were associated with the protection against CVDs and other diseases and to the improvement of the cells' oxidative stress tolerance. The results obtained for the anti-hypercholesterolemia properties, in addition to the revelation of the positive impact on cell metabolism, offer an important contribution for further evaluation of these seaweed extracts as functional foods or for CVD prevention.

Edible Seaweeds Extracts: Characterization and Functional Properties for Health Conditions.

Seaweeds are popular foods due to claimed beneficial health effects, but for many there is a lack of scientific evidence. In this study, extracts of the edible seaweeds Aramé, Nori, and Fucus are compared. Our approach intends to clarify similarities and differences in the health properties of these seaweeds, thus contributing to target potential applications for each. Additionally, although Aramé and Fucus seaweeds are highly explored, information on Nori composition and bioactivities is scarce. The aqueous extracts of the seaweeds were obtained by decoction, then fractionated and characterized according to their composition and biological activity. It was recognized that fractioning the extracts led to bioactivity reduction, suggesting a loss of bioactive compounds synergies. The Aramé extract showed the highest antioxidant activity and Nori exhibited the highest potential for acetylcholinesterase inhibition. The identification of the bioactive compounds in the extracts allowed to see that these contained a mixture of phloroglucinol polymers, and it was suggested that Nori's effect on acetylcholinesterase inhibition may be associated with a smaller sized phlorotannins capable of entering the enzyme active site. Overall, these results suggest a promising potential for the use of these seaweed extracts, mainly Aramé and Nori, in health improvement and management of diseases, namely those associated to oxidative stress and neurodegeneration.

Porphyra tenera Protects against PM2.5-Induced Cognitive Dysfunction with the Regulation of Gut Function.

To evaluate the biological effects of Porphyra tenera (P. tenera), we tried to confirm the possibility that the intake of P. tenera could modulate cognitive and intestinal functions in PM2.5-induced cognitive decline mice. P. tenera attenuated PM2.5-induced learning and memory impairment through antioxidant and anti-inflammatory effects by regulating the mitochondrial function and TLR-initiated NF-κB signaling. In addition, P. tenera effectively alleviated Aß production/tau phosphorylation by inhibiting the JNK phosphorylation. Also, the bioactive constituents of P. tenera determined the sulfated galactan, mycosporine-like amino acids (MAAs), and chlorophyll derivatives. Moreover, the bioactive compounds of P. tenera by gut fermentation protected against gut dysbiosis and intestinal tight junction damage with a decrease in inflammatory response and short-chain fatty acid production. Based on these results, our findings suggest that P. tenera with sulfated galactan and MAAs is a potential material for cognitive function improvement.

Inhibitory Effects of Polyphenols-Rich Components From Three Edible Seaweeds on Inflammation and Colon Cancer in vitro.

Polyphenols from edible seaweeds display various health benefits which have not been adequately studied. This study aimed to characterize the composition of extractable polyphenol-rich components (EPCs) and non-extractable polyphenol-rich components (NEPCs) from three edible seaweeds (i.e., Laminaria japonica, Ulva lactuca, and Porphyra tenera) and evaluate their anti-inflammatory capacities in activated macrophages and anticancer properties in colon cancer cells. Both EPCs and NEPCs from three edible seaweeds against lipopolysaccharides (LPS) stimulated nitric oxide in activated macrophages. Immunoblotting and qRT-PCR indicated that EPCs and NEPCs regulated the expression levels of proinflammatory enzymes, proinflammatory cytokines, and antioxidant enzymes in macrophages. Furthermore, EPCs and NEPCs lowered the viability of colon cancer cells, while normal colon cells were not affected. Additionally, EPCs and NEPCs induced cellular apoptosis and led to G0/G1 cell cycle arrest in HCT116 cells. Overall, these results provide a rationale for future animal and human studies designed to examine the anti-inflammatory and chemopreventive capacities of polyphenols-rich components from L. japonica, U. lactuca, and P. tenera.

Anti-Inflammatory Properties and Gut Microbiota Modulation of Porphyra tenera Extracts in Dextran Sodium Sulfate-Induced Colitis in Mice.

Porphyra tenera (PT) is a functional seaweed food that has been reported for health benefits such as antioxidant, immunostimulant, anti-inflammation, and hepatoprotective effects. In this study, we investigated the effect of PT extracts on gut microbiota modulation in colitis-induced mice. The mice experiment was designed as three groups including normal mice (CTL), dextran sodium sulfate (DSS)-fed mice, and DSS plus PT extracts-fed mice (PTE). DSS was administrated through drinking water containing DSS for 1 week, and the PT extract was ingested into the gastrointestinal tract in mice. PT extract ameliorated the decreased body weight and colon length and improved disease activity index and pro-inflammatory cytokine expression. In addition, PT extract significantly shifted the gut microbiota of mice. DSS treatment significantly increased the portion of harmful bacteria (i.e., Helicobacter, Mucipirillum, and Parasutterella) and decreased the butyrate producing bacteria (i.e., Acetatifactor, Alistipes, Oscillibacter, and Clostridium_XIVb). PT extract increased the abundance of genera Clostridium_XIVb and also enriched some of predicted metabolic activities such as glyoxylate cycle, ethylmalonyl-CoA pathway, nitrate reduction, creatinine degradation, and glycine betaine metabolism. These results suggest that PT extract may ameliorate the DSS-induced colitis inflammation through regulating the compositions and functions of gut microbiota in mice.

Effects of Porphyra tenera Supplementation on the Immune System: A Randomized, Double-Blind, and Placebo-Controlled Clinical Trial.

OBJECTIVE: The purpose of this study was to determine if Porphyra tenera extract (PTE) has immune-enhancing effects and is safe in healthy adults. METHODS: Subjects who met the inclusion criteria (3 × 103 ≤ peripheral blood leukocyte level ≥ 8 × 103 cells/µL) were recruited for this study. Enrolled subjects (n = 120) were randomly assigned to either the PTE group (n = 60) and were given 2.5 g/day of PTE (as PTE) in capsule form or the placebo group (n = 60) and were given crystal cellulose capsules with the identical appearance, weight, and flavor as the PTE capsules for 8 weeks. Outcomes were assessed based on measuring natural killer (NK) cell activity, cytokines level, and upper respiratory infection (URI), and safety parameters were assessed at baseline and 8 weeks. RESULTS: Compared with baseline, NK cell activity (%) increased for all effector cell-to-target cell ratios in the PTE group after 8 weeks; however, changes were not observed in the placebo group (p < 0.10). Subgroup analysis of 101 subjects without URI showed that NK cell activity in the PTE group tended to increase for all effector cell/target cell (E:T) ratios (E:T = 12.5:1 p = 0.068; E:T = 25:1 p = 0.036; E:T = 50:1 p = 0.081) compared with the placebo group. A significant difference between the two groups was observed for the E:T = 25:1 ratio, which increased from 20.3 ± 12.0% at baseline to 23.2 ± 12.4% after 8 weeks in the PTE group (p = 0.036). A significant difference was not observed in cytokine between the two groups. CONCLUSION: PTE supplementation appears to enhance immune function by improving NK cell activity without adverse effects in healthy adults.

Extracts of Porphyra tenera (Nori Seaweed) Activate the Immune Response in Mouse RAW264.7 Macrophages via NF-κB Signaling.

Porphyra tenera, also known as nori, is a red algal species of seaweed. It is cultivated in Asia for culinary purposes. We report that P. tenera extract (PTE) enhances the immune response in mouse macrophages. We found that P. tenera extract regulates the NF-κB IκB kinase (IKK) signaling pathway, and we assessed the expression and translocation of p65, a subunit of NF-κB, in RAW264.7 mouse macrophage cells after treatment with PTE. We also investigated the effects of 10% ethanol PTE (PTE10) in RAW264.7 cells. The production of IL-10, IL-6, TNF-α, and IFN-γ was induced by PTE treatment of the macrophages, and PTE also enhanced p-IκB and p-AKT. PTE10 showed no cytotoxicity at 10-20 µg/mL in RAW264.7 cells. PTE10, in fact, increased cell viability at 24 h, stimulated macrophage cells, and induced the phosphorylation of Akt. Akt stimulates IKK activity through the phosphorylation of IKKα and enhances immune activity through the activation of NF-κB. In this study, NF-κB activation was induced by increasing p-NF-κB and p-IKK. A subunit of NF-κB, p65, was located in the nucleus and increased the expression of various cytokines. PTE thus enhanced the immune response through IκB-α immunostimulation signaling in RAW264.7 cells. PTE10 has potential therefore for development of future treatments requiring immune system stimulation.

Chemical characterization and antioxidant potential of volatile oil from an edible seaweed Porphyra tenera (Kjellman, 1897).

BACKGROUND: Porphyra tenera (Kjellman, 1897) is the most common eatable red seaweed in Asia. In the present study, P. tenera volatile oil (PTVO) was extracted from dried P. tenera sheets that were used as food by the microwave hydrodistillation procedure, after which the characterization of its chemical constituents was done by gas chromatography and mass spectroscopy and its antioxidant potential was evaluated by a number of in vitro biochemical assays such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, nitric oxide (NO) scavenging, superoxide radical scavenging, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging, hydroxyl radical scavenging and reducing power assay and inhibition of lipid peroxidation. RESULTS: A total of 30 volatile compounds comprising about 99.4% of the total volume were identified, of which trans-beta-ionone (20.9%), hexadecanoic acid (9.2%) and 2,6-nonadienal (8.7%) were present in higher quantities. PTVO exhibited strong free radical scavenging activity by DPPH scavenging (44.62%), NO scavenging (28.45%) and superoxide scavenging (54.27%) at 500 µg/mL. Similarly, it displayed strong ABTS radical scavenging (IC50 value of 177.83 µg/mL), hydroxyl radical scavenging (IC50 value of 109.70 µg/mL), and moderate lipid peroxidation inhibition activity (IC50 value of 231.80 µg/mL) and reducing power (IC0.5 value of 126.58 µg/mL). PTVO exhibited strong antioxidant potential in a concentration dependent manner and the results were comparable with the BHT and α-tocopherol, taken as the reference standard compounds (positive controls). CONCLUSIONS: Taken together, PTVO with potential bioactive chemical compounds and strong antioxidant activity could be utilized in the cosmetic industries for making antioxidant rich anti-aging and sun-screen lotion and in the food sector industries as food additives and preservatives.

Barra de cereal adicionada da alga Porphyra Tenera: caracterização sensorial, físico-química e nutricional / Ceral bar added the alga Porphyra Tenera: sensory characterization, physical-chemistry and nutrition

Os alimentos funcionais são hoje prioridade de pesquisa nas áreas de nutrição e tecnologia de alimentos, levando-se em conta o interesse do consumidor em alimentos mais saudáveis. Este projeto teve como objetivo elaborar uma barra de cereal com adição da alga Porphyra tenera, morango, chocolate ao leite e meio amargo. Após a elaboração da barra, foram realizadas análises bromatológicas, sensoriais e a rotulagem nutricional. O trabalho foi desenvolvido no Laboratório de Bromatologia e Tecnologia de Alimentos do Centro Universitário de Caratinga, Minas Gerais. Foram produzidas duas amostras, sendo uma tradicional e a outra com adição de algas. A aceitabilidade da barra de cereal com adição de algas foi satisfatória (69% dos provadores), considerando que alimentos à base de algas não fazem parte da cultura brasileira, mas, em razão de suas propriedades nutricionais e funcionais, devem ser inseridos novos produtos explorando seus benefícios. Por meio das análises físico-químicas, a porcentagem de carboidratos foi de 53,27%; lipídeos, de 12,19%; e proteínas, de 5,64%. Observou-se que o produto é rico em fósforo, mineral essencial para o melhor funcionamento do organismo. A alga Porphyra tenera é rica em vários outros nutrientes, não analisados neste estudo, por causa das limitações dos equipamentos necessários do Laboratório de Bromatologia da instituição.

Studies on the extraction of polysaccharides sulfate from three algae and their scavenging activity on free radicals / 中国海洋药物

Objective The polysaccharides sulfate were extracted from three kinds of algae in-cluding porphyra tenera , Laminaria ja ponica and Sargassum fusi forme ( Harv. )Setch . in order to screen antioxidant with exploiting potential. Methods Using the assay system of DP-PH,the antioxidative activities of various extracts were studied. Results Three kinds of algae polysaccharides sulfate had different antioxidative activities. Moreover, polysaccharide extracted with different solvents had different intensities of antioxidative activity. Conclusion Polysacchride sulfate extracted with water has stronger antioxidative activity than that with others.keywolds antioxidation; porphyra tenera kjellm. ; Laminaria japonica; Sargassum fusi -forme ( Harv. )Setch.Studies on the extraction of polysaccharides sulfate from three algae and their scavenging activity on free radicalsHAN Hua,ZHOU Hai Yan,LIU Cheng-Chu,WANG Chun-bo(1.Bromatology Institute of Shanhai Aquatic University , Shanghai 200090, China; 2. Medical College , Qingdao University ,Qingdao 266021, China)Abstract:Objective The polysaccharides sulfate were extracted from three kinds of algae in-cluding porphyra tenera , Laminaria ja ponica and Sargassum fusi forme ( Harv. )Setch . in order to screen antioxidant with exploiting potential. Methods Using the assay system of DP-PH,the antioxidative activities of various extracts were studied. Results Three kinds of algae polysaccharides sulfate had different antioxidative activities. Moreover, polysaccharide extracted with different solvents had different intensities of antioxidative activity. Conclusion Polysacchride sulfate extracted with water has stronger antioxidative activity than that with others.