Seaweed prevents breast cancer?

Brown Algae Dictyopteris divaricata Attenuates Adipogenesis by Modulating Adipocyte Differentiation and Promoting Lipolysis through Heme Oxygenase-1 Activation in 3T3-L1 Cells

The present study aims to explore the probable anti-adipogenesis effect of Dictyopteris divaricata (D. divaricata) in 3T3-L1 preadipocytes by regulating heme oxygenase-1 (HO-1). The extract of D. divaricata retarded lipid accretion and decreased triglyceride (TG) content in 3T3-L1 adipocytes but increased free glycerol levels. Treatment with the extract inhibited lipogenesis by inhibiting protein expressions of fatty acid synthase (FAS) and lipoprotein lipase (LPL), whereas lipolysis increased by activating phosphorylation of hormone-sensitive lipase (p-HSL) and AMP-activated protein kinase (p-AMPK). The extract inhibited adipocyte differentiation of 3T3-L1 preadipocytes through down-regulating adipogenic transcription factors, including peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein 1 (SREBP1). This is attributed to the triggering of Wnt/β-catenin signaling. In addition, this study found that treatment with the extract activated HO-1 expression. Pharmacological approaches revealed that treatment with Zinc Protoporphyrin (ZnPP), an HO-1 inhibitor, resulted in an increase in lipid accumulation and a decrease in free glycerol levels. Finally, three adipogenic transcription factors, such as PPARγ, C/EBPα, and SREBP1, restored their expression in the presence of ZnPP. Analysis of chemical constituents revealed that the extract of D. divaricata is rich in 1,4-benzenediol, 7-tetradecenal, fucosterol, and n-hexadecanoic acid, which are known to have multiple pharmacological properties.

Characteristics and anti-inflammatory effects of the enzymatically extracted polysaccharides of Sargassum fulvellum using crude enzyme from Shewanella oneidensis PKA 1008

Alginic acid is a polysaccharide obtained from brown algae, and its oligosaccharide has various functions such as antiviral, antitumor, immunoregulation, and antioxidant. However, because of its high viscosity, numerous studies have degraded the alginic acid by enzymes to improve its utilisation. In the present work, we characterised Sargassum fulvellum enzymatic extract (SFEE) using polysaccharide-degrading enzyme obtained from Shewanella oneidensis PKA 1008, and investigated its anti-inflammatory potential. S. fulvellum powder and crude enzyme were mixed at a ratio of 1:1 (v/v), and reacted at 30°C for 0 - 48 h to obtain the optimum degrading time. The changes in pH, colour, reducing sugar, and viscosity of SFEE were determined. The anti-inflammatory activity of SFEE was confirmed by measuring the expression level of nitric oxide (NO) and pro-inflammatory cytokines (IL-6, TNF-α, and L-1β) in RAW 264.7 macrophage cell line. The reducing sugar content was found to increase 2.75-fold at 24 h as compared to that at the initial reaction point, but pH and viscosity decreased significantly with increasing reaction time. SFEE showed a high inhibitory effect on the levels of NO and pro-inflammatory cytokines. SFEE thus has great potential for development as a functional food and therapeutic material owing to its anti-inflammatory effect.

Properties and anti-inflammatory effects of Sargassum muticum enzymatic extracts decomposed using crude enzyme from Shewanella oneidensis PKA1008

This study was conducted to investigate the general properties of an enzymatic extract of Sargassum muticum (SM) produced using a crude enzyme from Shewanella oneidensis PKA 1008 and their anti-inflammatory activities. The SM was mixed with crude enzymes from S. oneidensis PKA 1008 (1:1 (v/v)) and incubated at 30 °C for 0, 3, 6, 12, 24, 48, and 60 h. S. oneidensis PKA 1008 crude enzyme showed the highest SM enzymatic extracts degradation ability when reacted with SM for 48 h. These evaluations demonstrated a 134.25% increase in reducing sugar content and a 14.90% reduction in viscosity at 48 h. The pH, lightness (L*) and yellowness (b*) of the SM enzymatic extracts decreased significantly with increasing reaction time. Moreover, the SM enzymatic extracts demonstrated significant anti-inflammatory activity. These results indicate that the crude enzyme from S. oneidensis PKA 1008 can be used to enhance the polysaccharide degradation of SM, and the resultant oligosaccharides may have an anti-inflammatory effect.

Fucoxanthin Is a Potential Therapeutic Agent for the Treatment of Breast Cancer

Breast cancer (BC) is one of the most common cancers diagnosed and the leading cause of cancer-related death in women. Although there are first-line treatments for BC, drug resistances and adverse events have been reported. Given the incidence of BC keeps increasing, seeking novel therapeutics is urgently needed. Fucoxanthin (Fx) is a dietary carotenoid commonly found in seaweeds and diatoms. Both in vitro and in vivo studies show that Fx and its deacetylated metabolite fucoxanthinol (Fxol) inhibit and prevent BC growth. The NF-κB signaling pathway is considered the major pathway contributing to the anti-proliferation, anti-angiogenesis and pro-apoptotic effects of Fx and Fxol. Other signaling molecules such as MAPK, MMP2/9, CYP and ROS are also involved in the anti-cancer effects by regulating the tumor microenvironment, cancer metastasis, carcinogen metabolism and oxidation. Besides, Fx also possesses anti-obesity effects by regulating UCP1 levels and lipid metabolism, which may help to reduce BC risk. More importantly, mounting evidence demonstrates that Fx overcomes drug resistance. This review aims to give an updated summary of the anti-cancer effects of Fx and summarize the underlying mechanisms of action, which will provide novel strategies for the development of Fx as an anti-cancer therapeutic agent.

Characterization and immunomodulatory activity of sulfated galactan from the red seaweed Gracilaria fisheri

Polysaccharides from the red seaweed Gracilaria fisheri possess many functions, which include antioxidant, antiviral, and antibacterial activities. However, detailed data on their immunomodulatory activities are scarce. Here, we isolated sulfated galactans (SG) from G. fisheri. We found that the predominant SG from G. fisheri, termed SG-1, had an estimated molecular mass of 100 kDa and activated murine J774A.1 macrophages via the dectin-1 signaling pathway. Furthermore, we observed enhancement of nitric oxide (NO) secretion, increased expression of inducible nitric oxide synthase (iNOS) mRNA, and increased mRNA levels of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukins IL-1β and IL-6 by SG-1 in macrophages. Moreover, there was higher expression of intercellular adhesion molecule 1 (ICAM-1) and co-stimulatory molecules (B7-1 and B7-2) mRNA. Treatment with G. fisheri SG-1 at 50 μg/mL generally achieved or exceeded the pro-inflammatory activities of 100 ng/mL lipopolysaccharide. Our study demonstrates immune-stimulatory activities of G. fisheri SG that may be of value for immune-potentiating treatment in humans or livestock.

Fungi and Algae as Sources of Medicinal and Other Biologically Active Compounds: A Review

Many species of fungi including lichenized fungi (lichens) and algae have the ability to biosynthesize biologically active compounds. They produce, among others, polysaccharides with anticancer and immunostimulatory properties: (1) Background: This paper presents the characteristics of the most important bioactive compounds produced by fungi and algae; (2) Methods: Based on the example of the selected species of mushrooms, lichens and algae, the therapeutic properties of the secondary metabolites that they produce and the possibilities of their use are presented; (3) Results: The importance of fungi, especially large-fruited mushrooms, lichens and algae, in nature and human life is discussed, in particular, with regard to their use in the pharmaceutical industry and their nutritional value; (4) Conclusions: The natural organisms, such as fungi, lichenized fungi and algae, could be used as supplementary medicine, in the form of pharmaceutical preparations and food sources. Further advanced studies are required on the pharmacological properties and bioactive compounds of these organisms.

Intestinal anti-inflammatory activity of Ulva ohnoi oil in DSS-induced experimental mouse model

This study was conducted to examine the physiological activity of Ulva ohnoi, some of which may be used for food or natural products but could disturbing coastal ecosystems due to large scale green-tide, to check values of U. ohnoi oil through experimental results. U. ohnoi oil was extracted from bulk of Ulva biomass to confirm its antioxidant and antibacterial activity, and the efficacy of U. ohnoi oil in the state of inflammation was confirmed through animal experiments. To confirm the anti-inflammatory effect, a mouse model induced with DSS was used. As a result of measuring NO using plasma after induction of inflammation, the amount of NO produced in the U. ohnoi oil group was decreased compared to the control group. Expression of inflammatory cytokines TNF-α, IL-6, and IL-1β was decreased compared to the control group. As a result of observing H&E staining, lower crypt loss and inflammatory cell infiltration were found in the U. ohnoi oil group compared to the control group. Consequently, U. ohnoi oil appears to have great anti-inflammatory properties.

Fucoxanthin Holds Potential to Become a Drug Adjuvant in Breast Cancer Treatment: Evidence from 2D and 3D Cell Cultures

Fucoxanthin (Fx) is a carotenoid derived from marine organisms that exhibits anticancer activities. However, its role as a potential drug adjuvant in breast cancer (BC) treatment is still poorly explored. Firstly, this study investigated the cytotoxic effects of Fx alone and combined with doxorubicin (Dox) and cisplatin (Cis) on a panel of 2D-cultured BC cell lines (MCF7, SKBR3 and MDA-MB-231) and one non-tumoral cell line (MCF12A). Fucoxanthin induced cytotoxicity against all the cell lines and potentiated Dox cytotoxic effects towards the SKBR3 and MDA-MB-231 cells. The combination triggering the highest cytotoxicity (Fx 10 µM + Dox 1 µM in MDA-MB-231) additionally showed significant induction of cell death and genotoxic effects, relative to control. In sequence, the same combination was tested on 3D cultures using a multi-endpoint approach involving bioactivity assays and microscopy techniques. Similar to 2D cultures, the combination of Fx and Dox showed higher cytotoxic effects on 3D cultures compared to the isolated compounds. Furthermore, this combination increased the number of apoptotic cells, decreased cell proliferation, and caused structural and ultrastructural damages on the 3D models. Overall, our findings suggest Fx has potential to become an adjuvant for Dox chemotherapy regimens in BC treatment.

Cytotoxicity of Seaweed Compounds, Alone or Combined to Reference Drugs, against Breast Cell Lines Cultured in 2D and 3D

Seaweed bioactive compounds have shown anticancer activities in in vitro and in vivo studies. However, tests remain limited, with conflicting results, and effects in combination with anticancer drugs are even scarcer. Here, the cytotoxic effects of five seaweed compounds (astaxanthin, fucoidan, fucosterol, laminarin, and phloroglucinol) were tested alone and in combination with anticancer drugs (cisplatin-Cis; and doxorubicin-Dox), in breast cell lines (three breast cancer (BC) subtypes and one non-tumoral). The combinations revealed situations where seaweed compounds presented potentiation or inhibition of the drugs' cytotoxicity, without a specific pattern, varying according to the cell line, concentration used for the combination, and drug. Fucosterol was the most promising compound, since: (i) it alone had the highest cytotoxicity at low concentrations against the BC lines without affecting the non-tumoral line; and (ii) in combination (at non-cytotoxic concentration), it potentiated Dox cytotoxicity in the triple-negative BC cell line. Using a comparative approach, monolayer versus 3D cultures, further investigation assessed effects on cell viability and proliferation, morphology, and immunocytochemistry targets. The cytotoxic and antiproliferative effects in monolayer were not observed in 3D, corroborating that cells in 3D culture are more resistant to treatments, and reinforcing the use of more complex models for drug screening and a multi-approach that should include histological and ICC analysis.

Anti-proliferative and ROS-inhibitory activities reveal the anticancer potential of Caulerpa species

Seaweeds are considered a promising functional food and safe for human consumption as they have significant health benefits. Five abundant tropical seaweeds, Caulerpa racemosa var. macrophysa, Caulerpa scalpelliformis, Grateloupia indica, Sargassum linearifolium, and Spatoglossum asperum rich in metabolites, phenolic, and flavonoid compounds, were analyzed for the anti-proliferative and ROS inhibitory activities including transcript expression of cancer-linked key genes and apoptosis. C. racemosa var. macrophysa showed the maximum effective activities with a lower dose of extract, about 130 ± 30 and 23 ± 1 μg ml^-1 EC₅₀ dose for HeLa and Huh-7, respectively, followed by C. scalpelliformis, showing EC₅₀ dose about 200 ± 10 and 140 ± 30 μg ml^-1, respectively. Similarly, about 56% and 54% ROS inhibition were determined with Caulerpa spp. for HeLa and Huh-7 cells, respectively. Results indicated that tropical green seaweed Caulerpa spp. (C. racemosa var. macrophysa and C. scalpelliformis) have substantial potential of ROS inhibition. Further, it was observed that different cancer-linked marker proteins encoding genes were deferentially expressed with seaweed extracts in different cell lines. Overall, it is concluded that Caulerpa spp. are rich in antioxidant and anti-proliferative activities. Caulerpa spp. have potential to be explored further for cancer preventive properties or functional food or nutraceuticals applications.

Serum Iodine and Breast Cancer Risk: A Prospective Nested Case-Control Study Stratified for Selenium Levels

BACKGROUND

Iodine has been suggested to protect against breast cancer, but there are no epidemiologic studies on individual risk. An interesting finding is that in areas where the exposure to both selenium and iodine are high (e.g., Japan), the risk of breast cancer is lower than in areas where selenium is high and iodine low (e.g., United States), or in areas where both are low (e.g., Northern Europe). The aim of this study was to investigate the association between prediagnostic serum iodine levels and subsequent breast cancer risk, and to investigate if this potential association was modified by selenium levels.

METHODS

The Malmö Diet and Cancer Study provided prediagnostic serum samples and the current analysis included 1,159 breast cancer cases and 1,136 controls. Levels of baseline serum iodine and selenium were analyzed. A logistic regression analysis yielded ORs with 95% confidence intervals adjusted for potential confounders.

RESULTS

There was no evidence of an overall association between iodine levels and risk of breast cancer. Among women with high selenium levels (above the median), high iodine levels were associated with a lower risk of breast cancer; the OR for above versus below the median was 0.75 (0.57-0.99). The corresponding OR for women with low selenium was 1.15 (0.87-1.50), and the P _interaction was 0.06.

CONCLUSIONS

The combination of high serum iodine levels and high selenium levels was associated with a lower risk of breast cancer.

IMPACT

A high iodine and selenium exposure may decrease the risk of breast cancer.

Phenolic Extract of Seagrass, Halophila ovalis Activates Intrinsic Pathway of Apoptosis in Human Breast Cancer (MCF-7) Cells

The marine ecosystem is considered as a treasure of numerous novel biologically active molecules. We investigated the anticancer potential of the phenolic extract of Halophila ovalis in breast cancer (MCF-7) cells and characterized the possible underlying molecular mechanism. The phenolic extract (5 µl) of H. ovalis effectively inhibited the growth of MCF-7 cells. The results of DAPI staining indicated that this phenolic extract potently induces apoptosis in MCF-7 cells which was observed by increased chromatin condensation in the treated cells. An increased expression of the active fragments of an executioner caspase, caspase 3 in phenolic extract-treated MCF-7 cells further confirms this apoptosis induction. In consequence, the loss of mitochondrial membrane potential was noticed in treated cells. The protein expression analyzes show decreased expression of the anti-apoptotic protein, Bcl-2, and DNA repair enzyme, PARP in treated cells indicating the probable molecular targets of apoptosis. Further, the phenolic extract of H. ovalis blocked the antioxidant defense system in MCF-7 cells by down-regulating the protein expression of a major transcription factor, Nrf-2 and regulatory antioxidant enzymes, SOD-2 and HO-1. These results show the presence of chemopreventive compound(s) in the phenolic extract, which offers a platform for future studies to identify the active principles.

Degradation of Fucoxanthin to Elucidate the Relationship between the Fucoxanthin Molecular Structure and Its Antiproliferative Effect on Caco-2 Cells

Fucoxanthin has an antiproliferative effect on cancer cells, but its detailed structure⁻activity correlation has not yet been elucidated. To elucidate this correlation, fucoxanthin was degraded by ozonolysis. The degraded compounds of fucoxanthin obtained by ozonolysis were purified by HPLC and analyzed by NMR. The polyene chain of fucoxanthin was cleaved by ozonolysis, and the fucoxanthin was divided into two types of cyclohexyl derivatives, one with a β,γ-epoxy ketone group and the other with an allenic bond. In order to elucidate the structure⁻activity correlation, Caco-2 cells (human colorectal carcinoma) were treated with fucoxanthin degradation compounds. It was found that the entire structure of fucoxanthin is not essential for its antiproliferative effect and that even a partial structure exerts this effect.

Dietary intake of iodine-enriched eggs decreases the incidence of mouse mammary tumors caused by the activated ErbB2 oncogene

Human epigenetic studies suggest that consumption of seaweed prevents mammary cancer, which possibly is explained by iodine daily intake. In this study, we evaluated the efficacy of dietary intake of iodine-enriched eggs on mammary tumor incidence caused by the expression of activated type ErbB2. Female transgenic mice were divided into three groups, and fed a basic diet, a diet supplemented with ordinary eggs, or with iodine-enriched eggs. The number of mammary tumors greater than 5 mm in diameter was recorded in mice at 6 months of age. We report that the average number of mammary tumors per mouse was significantly lower in the iodine-enriched egg-added diet group than in either the basic diet or ordinary egg diet groups. These results indicate that iodine intake through livestock-derived products can reduce the incidence of mammary cancers caused by the expression of activated type ErbB2.

Iodine stimulates estrogen receptor singling and its systemic level is increased in surgical patients due to topical absorption

Iodine is crucial for thyroid hormone production. However, recent epidemiologic studies have shown that breast cancer patients have an elevated risk of developing thyroid cancer and vice versa. A notable finding in this study is that iodine stimulated the transcriptional activity of estrogen receptor-α (ER-α) in breast cancer cells. Iodine stimulated expression of several ER-α regulated gene including PS2, Cathepsin D, CyclinD1, and PR both in vitro and in nude mice, which is consistent with its stimulation of both anchorage-dependent and -independent growth of ER-α positive breast cancer cells and the effect to dampen tumor shrinkage of MCF-7 xenograft in ovariectomized nude mice. Analyses of clinical urine samples from breast cancer patients undergoing surgery demonstrated that urinary iodine levels were significantly higher than that in controls; and this increased level is due to the antiseptic use of iodine during breast surgery. The present study indicates that excess iodine intake may be an unfavorable factor in breast cancer by stimulation of ER-α transcriptional activity.

The thyroid and breast cancer

PURPOSE OF REVIEW

The female predominance of diseases of the thyroid and breast makes difficult the separation of an expected association with a causal linkage. This review will examine recent reports on associations between thyroid disease and breast cancer, comparing them with previous studies, with a view to elucidating what pointers are available to suggest either a common pathogenesis or novel thyroid-related therapeutic approach, which might arise from this association.

RECENT FINDINGS

Reports on thyroid-breast cancer associations are reviewed under the following headings: breast cancer prevalence in different thyroid disorders and their effect on risk and outcome; the possible role of thyroid autoimmunity, thyroid enlargement, effect of radioactive iodine treatment, role of stable iodine, possible joint antigens sodium iodide transporter and thyroid peroxidase and thyroid-breast cancer coincidence.

SUMMARY

Current studies on thyroid and breast cancer associations confirm earlier findings of the lack of definitive evidence of a causal relationship. The predominant relationship continues to be hypothyroidism or autoimmune thyroid disease perhaps contributing to increased breast cancer risk or outcomes. However, despite many studies and the findings of meta-analyses, elucidating the mechanisms underlying the association remains elusive. At present, there is little justification for utilizing thyroid insights as a possible therapeutic intervention in breast cancer.

Biological Activities of Isolated Compounds from Three Edible Malaysian Red Seaweeds,Gracilaria changii, G. manilaensisandGracilariasp

Gracilaria species are red marine macroalgae that are found abundantly in Malaysia. Gracilaria changii from Morib, Selangor, G. manilaensis and Gracilaria sp. from Gelang Patah, Johor were used in this study. Five compounds were successfully isolated and identified as hexadecanoic acid (1), cholest-5-en-3-ol (2), 2-hydroxymyristic acid (3), cholesteryl myristate (4) and 1-(4'-methoxyphenyl)-3-(2”,4”,6”-trihydroxyphenyl)-3-hydroxypropanone (5) based on spectral data analysis (IR, UV, GC-MS,1H NMR,13C NMR, HMQC and HMBC). All compounds isolated were tested for cytotoxicity (MTT assay for HL-60 and MCF-7 cell lines), and antibacterial (disc diffusion method), antioxidant (DPPH free radical scavenging assay and xanthine oxidase inhibitory assay) and acetylcholinesterase inhibitory (AChE) activity (TLC bioautographic method). Compounds 1 and 3 exhibited strong cytotoxic activity against HL-60 and MCF-7 cell lines. Compound 5 showed high antioxidant activity in both the DPPH free radical scavenging and xanthine oxidase inhibition assays. Compound 1 showed positive activity for AChE inhibitory with a minimum inhibition dose of 0.625 μg sample. All compounds demonstrated antibacterial activity producing 8 to 14 mm inhibition zones. A positive control was applied to all bioassays and experiments were performed with three replicates. Results demonstrated that three edible red seaweeds are rich sources of bioactive compounds with potential application for pharmaceutical purposes.

Use of Iodine to Biofortify and Promote Growth and Stress Tolerance in Crops

Iodine is not considered essential for land plants; however, in some aquatic plants, iodine plays a critical role in antioxidant metabolism. In humans, iodine is essential for the metabolism of the thyroid and for the development of cognitive abilities, and it is associated with lower risks of developing certain types of cancer. Therefore, great efforts are made to ensure the proper intake of iodine to the population, for example, the iodization of table salt. In the same way, as an alternative, the use of different iodine fertilization techniques to biofortify crops is considered an adequate iodine supply method. Hence, biofortification with iodine is an active area of research, with highly relevant results. The agricultural application of iodine to enhance growth, environmental adaptation, and stress tolerance in plants has not been well explored, although it may lead to the increased use of this element in agricultural practice and thus contribute to the biofortification of crops. This review systematically presents the results published on the application of iodine in agriculture, considering different environmental conditions and farming systems in various species and varying concentrations of the element, its chemical forms, and its application method. Some studies report beneficial effects of iodine, including better growth, and changes in the tolerance to stress and antioxidant capacity, while other studies report that the applications of iodine cause no response or even have adverse effects. We suggested different assumptions that attempt to explain these conflicting results, considering the possible interaction of iodine with other trace elements, as well as the different physicochemical and biogeochemical conditions that give rise to the distinct availability and the volatilization of the element.

Chemoprotective effects of a recombinant protein from Pyropia yezoensis and synthetic peptide against acetaminophen-induced Chang liver cell death

In the present study, the chemoprotective effects of recombinant Pyropia yezoensis (P. yezoensis) protein 1 (PYP1) were examined in acetaminophen (APAP)-treated Chang liver cells. The analysis of P. yezoensis revealed the presence of both mature and immature variants of PYP1. PYP1s, designated as PYP1 (15 kDa), PYP1-AC (12 kDa) and PYP1-B (5 kDa), were successfully expressed in Escherichia coli, and their chemoprotective effects were then examined. In addition, a peptide of 11 residues (ALEGGKSSGGG), which is a common sequence at the N-terminus all of the PYP1s, was synthesized and examined. The effects of treatment with PYP1s and the synthetic peptide (SP) on cell proliferation were determined by MTS assay. Our results clearly demonstrated that treatment with all the PYP1s and SP significantly promoted the proliferation of Chang liver cells, protecting them against APAP. Thus, we concluded that recombinant PYP1s exert protective effects against injury to Chang liver cells.

Protective Effects of Turbinaria ornata and Padina pavonia against Azoxymethane-Induced Colon Carcinogenesis through Modulation of PPAR Gamma, NF-κB and Oxidative Stress

The aim of this study was to investigate the antiproliferative and protective effects of the brown seaweeds, Turbinaria ornata and Padina pavonia, against azoxymethane (AOM)-induced colon carcinogenesis in mice. Both algal extracts showed anti-proliferative effects on the human carcinoma cell line HCT-116 in vitro, with T. ornata demonstrating a more potent effect. Male albino Swiss mice received intraperitoneal injections of AOM (10 mg/kg) once a week for two consecutive weeks and 100 mg/kg of either T. ornata or P. pavonia extracts. AOM-induced mice exhibited alterations in the histological structure of the colon, elevated lipid peroxidation and nitric oxide, declined glutathione content and reduced activity of superoxide dismutase and glutathione peroxidase. In addition, AOM induced downregulation of peroxisome proliferator activated receptor gamma (PPARγ) and p53 mRNA expression, with concomitant upregulation of nuclear factor-kappa B (NF-κB) in colon tissue. Administration of either algal extract markedly alleviated the recorded alterations. In conclusion, the current study suggests that T. ornata and P. pavonia, through their antioxidant and anti-inflammatory effects, are able to attenuate colon inflammation by downregulating NF-κB expression. Furthermore, the protective effects of both algae against AOM-initiated carcinogenesis were attributed, at least in part, to their ability to upregulate colonic PPARγ and p53 expression.

Methanolic extracts from brown seaweeds Dictyota cilliolata and Dictyota menstrualis induce apoptosis in human cervical adenocarcinoma HeLa cells

Carcinoma of the uterine cervix is the second most common female tumor worldwide, surpassed only by breast cancer. Natural products from seaweeds evidencing apoptotic activity have attracted a great deal of attention as new leads for alternative and complementary preventive or therapeutic anticancer agents. Here, methanol extracts from 13 species of tropical seaweeds (Rhodophytas, Phaeophyta and Chlorophyta) collected from the Northeast of Brazil were assessed as apoptosis-inducing agents on human cervical adenocarcinoma (HeLa). All extracts showed different levels of cytotoxicity against HeLa cells; the most potent were obtained from the brown alga Dictyota cilliolata (MEDC) and Dictyota menstrualis (MEDM). In addition, MEDC and MEDM also inhibits SiHa (cervix carcinoma) cell proliferation. Studies with these two extracts using flow cytometry and fluorescence microscopy showed that HeLa cells exposed to MEDM and MEDC exhibit morphological and biochemical changes that characterize apoptosis as shown by loss of cell viability, chromatin condensation, phosphatidylserine externalization, and sub-G1 cell cycle phase accumulation, also MEDC induces cell cycle arrest in cell cycle phase S. Moreover, the activation of caspases 3 and 9 by these extracts suggests a mitochondria-dependent apoptosis route. However, other routes cannot be ruled out. Together, these results point out the methanol extracts of the brown algae D. mentrualis and D. cilliolata as potential sources of molecules with antitumor activity.

Anticancer effects of different seaweeds on human colon and breast cancers

Seafoods and seaweeds represent some of the most important reservoirs of new therapeutic compounds for humans. Seaweed has been shown to have several biological activities, including anticancer activity. This review focuses on colorectal and breast cancers, which are major causes of cancer-related mortality in men and women. It also describes various compounds extracted from a range of seaweeds that have been shown to eradicate or slow the progression of cancer. Fucoidan extracted from the brown algae Fucus spp. has shown activity against both colorectal and breast cancers. Furthermore, we review the mechanisms through which these compounds can induce apoptosis in vitro and in vivo. By considering the ability of compounds present in seaweeds to act against colorectal and breast cancers, this review highlights the potential use of seaweeds as anticancer agents.

Anticancer effect of fucoidan in combination with tyrosine kinase inhibitor lapatinib

Background. Despite a number of in vitro and in vivo studies reporting the efficacy of fucoidan in treating various cancers, few studies have measured the efficacy of dietary fucoidan (DF) in combination with cancer drugs. Thus, we examined the sensitivity of DF in combination with the EGFR/ERBB2-targeting reagent lapatinib on cancer cells. Method. We selected six EGFR/ERBB2-amplified cancer cell lines (OE19, NCI-N87, OE33, ESO26, MKN7, and BT474) as an in vitro model and tested their sensitivity to DF alone and to DF in combination with the well-known EGFR/ERBB2-targeting reagent lapatinib. Result. Overall, in drug independent sensitivity test, DF alone did not significantly inhibit the growth of EGFR/ERBB2-amplified cancer cells in vitro. When DF was given in combination with lapatinib, however, it tended to synergistically inhibit cell growth in OE33 but antagonized the action of lapatinib in ESO26, NCI-N87, and OE19. Conclusion. This study suggests that DF has the potential to increase or decrease the effects of certain anticancer drugs on certain cancer cell types. Further study is needed to explore the mechanism of interaction and synergistic antitumor activity of DF in combination with chemotherapy and targeted therapy.

Anticancer and antitumor potential of fucoidan and fucoxanthin, two main metabolites isolated from brown algae

Seaweed is one of the largest producers of biomass in marine environment and is a rich arsenal of active metabolites and functional ingredients with valuable beneficial health effects. Being a staple part of Asian cuisine, investigations on the crude extracts of Phaeophyceae or brown algae revealed marked antitumor activity, eliciting a variety of research to determine the active ingredients involved in this potential. The sulfated polysaccharide of fucoidan and carotenoid of fucoxanthin were found to be the most important active metabolites of brown algae as potential chemotherapeutic or chemopreventive agents. This review strives to provide detailed account of all current knowledge on the anticancer and antitumor activity of fucoidan and fucoxanthin as the two major metabolites isolated from brown algae.

Phlorotannins isolated from the edible brown alga Ecklonia stolonifera exert anti-adipogenic activity on 3T3-L1 adipocytes by downregulating C/EBPα and PPARγ

The dramatic increase in obesity-related diseases emphasizes the need to elucidate the cellular and molecular mechanisms underlying fat metabolism. Inhibition of adipocyte differentiation has been suggested to be an important strategy for preventing or treating obesity. In our previous study, we characterized an Ecklonia stolonifera extract and non-polar fractions thereof, including dichloromethane and ethyl acetate fractions. We showed that these fractions inhibited adipocyte differentiation and lipid formation/accumulation in 3T3-L1 preadipocytes, as assessed by Oil Red O staining. As part of our ongoing search for anti-obesity agents derived from E. stolonifera, in this work, we characterized five known phlorotannins, including phloroglucinol, eckol, dieckol, dioxinodehydroeckol, and phlorofucofuroeckol A, all of which were isolated from the active ethyl acetate fraction of E. stolonifera. We determined the chemical structures of these phlorotannins through comparisons of published nuclear magnetic resonance (NMR) spectral data. Furthermore, we screened these phlorotannins for their abilities to inhibit adipogenesis over a range of concentrations (12.5-100 μM). Of these five phlorotannins, phloroglucinol, eckol, and phlorofucofuroeckol A significantly concentration-dependently inhibited lipid accumulation in 3T3-L1 cells without affecting cell viability. In addition, the five isolated phlorotannins also significantly reduced the expression levels of several adipocyte marker genes, including proliferator activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), although they did so to different extents. These results suggest that the molecular weight of a phlorotannin is an important factor affecting its ability to inhibit adipocyte differentiation and modulate the expression levels of adipocyte marker genes.

Comparison of tamoxifen with edible seaweed (Eucheuma cottonii L.) extract in suppressing breast tumor

The tropical edible red seaweed (Eucheuma cottonii L.) is rich in nutrients and polyphenolic compounds that may suppress cancer through its antioxidant and antiproliferative properties. The study reports on rat mammary tumor suppression and tissue antioxidant status modulation by E. cottonii ethanol extract (ECE). The effect of orally administered ECE (100 mg/kg body-weight) was compared with that of tamoxifen (10 mg/kg body-weight). Rat was induced to develop mammary tumor with subcutaneous injection of LA-7 cells (6 × 10(6) cells/rat). The ECE was more effective than tamoxifen in suppressing tumor growth (27%), improving tissues (plasma, liver, and kidney) malondialdehyde concentrations, superoxide dismutase activity and erythrocyte glutathione concentrations (P < 0.05). Unlike tamoxifen, the ECE displayed little toxicity to the liver and kidneys. The ECE exhibited strong anticancer effect with enzyme modulating properties, suggesting its potential as a suppressing agent for mammary gland tumor.

Fucoxanthin: a marine carotenoid exerting anti-cancer effects by affecting multiple mechanisms

Fucoxanthin is a marine carotenoid exhibiting several health benefits. The anti-cancer effect of fucoxanthin and its deacetylated metabolite, fucoxanthinol, is well documented. In view of its potent anti-carcinogenic activity, the need to understand the underlying mechanisms has gained prominence. Towards achieving this goal, several researchers have carried out studies in various cell lines and in vivo and have deciphered that fucoxanthin exerts its anti-proliferative and cancer preventing influence via different molecules and pathways including the Bcl-2 proteins, MAPK, NFκB, Caspases, GADD45, and several other molecules that are involved in either cell cycle arrest, apoptosis, or metastasis. Thus, in addition to decreasing the frequency of occurrence and growth of tumours, fucoxanthin has a cytotoxic effect on cancer cells. Some studies show that this effect is selective, i.e., fucoxanthin has the capability to target cancer cells only, leaving normal physiological cells unaffected/less affected. Hence, fucoxanthin and its metabolites show great promise as chemotherapeutic agents in cancer.

Biomedical Properties of Edible Seaweed in Cancer Therapy and Chemoprevention Trials: A Review

This review article summarizes in vitro and in vivo experiments on seaweed anticancer activity and seaweed chemical components. Seaweed use in cancer therapy, chemopreventive randomized control trials (RCTs) and quasi-experiments are discussed. The literature reviewed in this article was obtained from various scientific sources and encompasses publications from 2000–2012. Seaweed therapeutic effects were deemed scientifically plausible and may be partially explained by the in vivo and in vitro pharmacological studies described. Although the mechanisms of action remain unclear, seaweed's anticancer properties may be attributable to its major biologically active metabolites. Much of the seaweed research outlined in this paper can serve as a foundation for explaining seaweed anticancer bioactivity. This review will open doors for developing strategies to treat malignancies using seaweed natural products.

Antioxidant, antiproliferative, and antiangiogenesis effects of polyphenol-rich seaweed (Sargassum muticum)

In the present study, we evaluated the effect of brown seaweeds Sargassum muticum methanolic extract (SMME), against MCF-7 and MDA-MB-231 breast cancer cell lines proliferation. This algae extract was also evaluated for reducing activity and total polyphenol content. The MTT assay results indicated that the extracts were cytotoxic against breast cancer cell lines in a dose-dependent manner, with IC50 of 22 μg/ml for MCF-7 and 55 μg/ml for MDA-MB-231 cell lines. The percentages of apoptotic MCF-7-treated cells increased from 13% to 67% by increasing the concentration of the SMME. The antiproliferative efficacy of this algal extract was positively correlated with the total polyphenol contents, suggesting a causal link related to extract content of phenolic acids. Cell cycle analysis showed a significant increase in the accumulation of SMME-treated cells at sub-G1 phase, indicating the induction of apoptosis by SMME. Further apoptosis induction was confirmed by Hoechst 33342 and AO/PI staining. Also SMME implanted in vivo into fertilized chicken eggs induced dose-related antiangiogenic activity in the chorioallantoic membrane (CAM). Our results imply a new insight on the novel function of Sargassum muticum polyphenol-rich seaweed in cancer research by induction of apoptosis, antioxidant, and antiangiogenesis effects.

Photoprotective effect of Undaria crenata against ultraviolet B-induced damage to keratinocytes

Chronic exposure of the skin to ultraviolet B (UVB) radiation induces oxidative stress, which plays a crucial role in the induction of skin cancer. The brown alga Undaria crenata is a potential source of antioxidant and anti-apoptotic compounds due to its capacity to produce protective compounds against environmental factors, including UV radiation. The aim of this study was to investigate the photoprotective properties of an U. crenata ethanol extract (UCE) against UVB-induced cell damage in human HaCaT keratinocytes. UCE exhibited absorbing effect of UVB (280-320 nm) and scavenging activity against the 1,1-diphenyl-2-picrylhydrazyl radical and intracellular reactive oxygen species induced by hydrogen peroxide and UVB rays. Furthermore, electron spin resonance spectrometry revealed the significant scavenging effect of UCE against superoxide anion and hydroxyl radical. UCE reduced UVB-induced apoptosis, as shown by a decrease in apoptotic bodies and nuclear and DNA fragmentation, resulting in the recovery of cell viability. UCE also decreased the degree of UVB-induced oxidative stress to lipids, proteins, and DNA as shown by a decrease in 8-isoprostane level, protein carbonylation and DNA tails. These results suggest that UCE protects human keratinocytes against UVB-induced oxidative stress.

Antioxidant marine products in cancer chemoprevention

SIGNIFICANCE

Oxidative stress resulting from excessive reactive oxygen/nitrogen/electrophilic species (ROS/RNS/RES) can lead to diseases such as cancer. The health benefits of dietary fruits and vegetables with antioxidant potential have received a great deal of attention. On the other hand, marine botanicals have been less well characterized and still remain as terra incognita.

RECENT ADVANCES

In some parts of the world, appreciable quantities of seaweeds are consumed on a daily basis. Along with current globalization, cuisines using seaweeds are now being used throughout the world, sometimes considered as healthy delicacies. Thus, it is relevant to explore the medicinal and pharmacological properties of seaweeds, as well as the health ramifications of this dietary practice.

CRITICAL ISSUES

We currently review the antioxidant potential of seaweed components such as sulfated polysaccharides, phenolic compounds (phlorotannins and bromophenols), and fucoxanthins. In addition to seaweeds, the chemistry and antioxidant activities of some marine fungi and bacteria are described. Since antioxidants are considered promising cancer chemopreventive agents, the in vitro, in vivo, and clinical aspects of antioxidant marine products are presented, and potential implications are discussed.

FUTURE DIRECTIONS

Although some data suggest that health benefits are derived from the consumption of marine natural products, further epidemiological or clinical studies are needed to strengthen these observations. In addition, many studies have demonstrated the antioxidant effects of seaweeds with in vitro models, but further characterization of bioavailability is necessary to suggest the significance of these responses. It is also important to define the safety of some seaweeds containing inorganic arsenics.

Differential growth inhibition of cancer cell lines and antioxidant activity of extracts of red, brown, and green marine algae

As the use of various anticancer drugs is associated with many undesirable side effects, there is an urgent need for the discovery of new, better, and specific anticancer compounds. Antioxidant and antiproliferative activities as well as effects on cell morphology were investigated for methanol (M), chloroform (C), ethyl acetate (E), and aqueous (A) extracts of Caulerpa peltata, Gelidiella acerosa, Padina gymnospora, and Sargassum wightii using 2,2-diphenyl-1-picrylhydrazyl radical-scavenging, ferrous ion chelation, and resazurin-based growth inhibition (in A549, HCT-15, MG-63, and PC-3 cell lines) assays. A general trend was the greater extraction of phenols and flavonoids by chloroform and ethyl acetate, which showed higher activity in many assays. These non-polar C and E extracts showed higher DPPH radical-scavenging and growth inhibitory activities in A549, HCT-15, and PC-3 cells. However, higher ferrous ion chelation (A extracts) and growth inhibition in MG-63 cells (M and A extracts) were seen for the polar extracts. Furthermore, P. gymnospora and C. peltata emerged as promising sources for antiproliferative agents that could be explored for their own activity and as leads for the development of other compounds.

Antioxidant and anticancer activities of selected persian gulf algae

In the present study, the effect of red (Gracillaria corticata), green (Ulva fasciata) and brown (Sargassum ilicifolium) seaweeds alcoholic extract, against five important human cancer cell lines (MCF-7, MDA-MB-231, HeLa, HepG2, and HT-29) proliferation, apoptosis and cell cycle arrest were evaluated. The reducing activity and total polyphenol content were also investigated. MTT assay was used for cytotoxicity test. Morphological alterations were examined using phase contrast, fluorescent and electron microscopy. All the extracts were antiproliferative against all the cancer cell lines, dose-dependently, with G. corticata methanol extract (GCME) having the greatest inhibition activity against MCF-7 cell line. The percentage of apoptosis increased from 18 to 78 %. The cell cycle analysis also showed that GCME can induce apoptosis which confirm by TEM. Algal extract reducing activities were as follows: G. corticata > S. ilicifolium > U. fasciata. The GCME is a good source of potential complementary and alternative functional food for prevention and treatment of cancer.

Induction of apoptosis by low-molecular-weight fucoidan through calcium- and caspase-dependent mitochondrial pathways in MDA-MB-231 breast cancer cells

Fucoidan, a fucose-rich polysaccharide extracted from brown seaweed, has antitumor, anticoagulant, antiviral, anti-inflammatory, and antibacterial activities. Several studies have shown that a fucoidan treatment of cancer cells induced cytotoxicity and apoptosis and inhibited angiogenesis and invasion. We investigated in the present study the effect of low-molecular-weight fucoidan (LMWF) on apoptosis in estrogen receptor-negative MDA-MB-231 human breast cancer cells. The LMWF treatment of MDA-MB-231 cells was associated with the activation of caspases and mitochondrial dysfunction, including dissipation of the mitochondrial membrane potential (ΔΨm), alteration of Ca(2+) homeostasis, cytochrome c release, and decreased expression of antiapoptotic Bcl-2 family proteins. Understanding the molecular events that mediated LMWF-induced MDA-MB-231 cell death will contribute to a more rational approach to cancer chemotherapy.

Induction of apoptosis signaling by glycoprotein of Capsosiphon fulvescens in human gastric cancer (AGS) cells

Capsosiphon fulvescens is a well-known green sea algae that has been touted in recent years as a potential anticancer drug. In this study, C. fulvescens glycoprotein (Cf-GP) showed proapoptotic signaling in AGS cells. An MTS assay indicated that Cf-GP inhibited the proliferation of AGS cell lines in a dose-dependent manner. Cells were treated with Cf-GP and the expression of proteins associated with apoptosis was examined by Western blotting. Based on the Western blot, expression of Cf-GP-activated caspase-cascade and PARP, which is a substrate of caspase-3 and -8, and proteins of the Bcl-2 family was observed. Cf-GP treatment stimulated the release of cytochrome C and apoptotic protease activating factor-1 from mitochondria to the cytosol. Cf-GP inhibited the growth of AGS cells through induction of sub-G1 phase arrest. We confirmed that sub-G1-phase arrest was associated with a decrease in the expression of cyclin D, cyclin E, Cdk2, Cdk4, and Cdk6, and an increase in the protein levels of p21 and p27. As a result, the increased sub-G1 ratio appears to be inhibited by cell proliferation. Therefore, we can confirm apoptosis in the AGS cells. Our results suggest that Cf-GP could be a potential source of biofunctional material that shows anticancer effects in human gastrointestinal cancer.

Antioxidant effects of fermented sea tangle (Laminaria japonica) by Lactobacillus brevis BJ20 in individuals with high level of γ-GT: A randomized, double-blind, and placebo-controlled clinical study

A randomized, double-blind, and placebo-controlled clinical study was performed to evaluate the antioxidant effects of fermented sea tangle (FST) on healthy volunteers with high levels of γ-glutamyltransferse (γ-GT). Forty-eight participants were divided into a placebo group and an FST group that received FST (1.5 g/day) for 4 weeks. Serum γ-GT, malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities were determined before and after the trial. Administering FST significantly decreased serum levels of γ-GT and MDA. Additionally, SOD and CAT activities were significantly augmented compared to those in the placebo group after 4 weeks, but no significant alteration was observed in GPx activity compared to that in the placebo group. Our findings indicate that FST enhanced the antioxidant defense system in a healthy population and may be useful as a functional food ingredient.

Cladribine enhances apoptotic cell death in lung carcinoma cells over-expressing DNase γ

Worldwide, lung cancer is the most common form of cancer and often has a poor prognosis. Establishment of effective therapies for lung cancer is a major concern in clinical cancer research. We compared the cytotoxic effects of chemotherapeutic agents including cisplatin, 5-fluorouracil, vinorelbine and cladribine, on a human lung cancer cell line, A549, and its derivative transfected with the DNase γ gene. We observed selective cytotoxicity of cladribine on the DNase γ-expressing sub-cell line of A549. Cladribine induces selective apoptosis in DNase γ-expressing A549 cells, which depends on activation of caspases. These results suggest that a combination therapy that includes cladribine along with the introduction of DNase γ has potential as a new therapeutic strategy for lung cancer.

Serum IGF-1 concentrations change with soy and seaweed supplements in healthy postmenopausal American women

Insulin-like growth factor 1 (IGF-1) is an anabolic hormone important for growth and development. However, high-circulating serum concentrations in adults are associated with increased risk of postmenopausal breast cancer. Nutritional status and specific foods influence serum IGF-1 concentrations. Breast cancer incidence is typically low in Asian countries where soy is commonly consumed. Paradoxically, soy supplement trials in American women have reported significant increases in IGF-1. Seaweed also is consumed regularly in Asian countries where breast cancer risk is low. We investigated the possibility that seaweed could modify soy-associated increases in IGF-1 in American women. Thirty healthy postmenopausal women (mean age 58 yr) participated in this 14-wk double-blinded, randomized, placebo-controlled crossover clinical trial. Participants consumed 5 g/day placebo or seaweed (Alaria esculenta) in capsules for 7 wk. During the 7th wk, a high-soy protein isolate powder was added (2 mg/kg body weight aglycone equivalent isoflavones). Overnight fasting blood samples were collected after each intervention period. Soy significantly increased serum IGF-1 concentrations compared to the placebo (21.2 nmol/L for soy vs. 16.9 nmol/L for placebo; P = 0.0001). The combination of seaweed and soy significantly reduced this increase by about 40% (21.2 nmol/L for soy alone vs. 19.4 nmol/L; P = 0.01). Concurrent seaweed and soy consumption may be important in modifying the effect of soy on IGF-1 serum concentrations.

A combined Phase I and II open-label study on the immunomodulatory effects of seaweed extract nutrient complex

Background:

Isolated fucoidans from brown marine algae have been shown to have a range of immune-modulating effects. This exploratory study aimed to determine whether a seaweed nutrient complex containing a blend of extracts from three different species of brown algae plus nutrients is safe to administer and has biological potential as an immune modulator. The study was undertaken as an open-label combined Phase I and II study.

Methods:

Participants (n = 10) were randomized to receive the study medication at either a 100 mg (n = 5) or 1000 mg (n = 5) dose over 4 weeks. The primary outcome measurement was in vivo changes in lymphocyte subsets. The secondary outcome measures were ex vivo changes in T-lymphocyte (CD4 and CD8) activation, phagocytosis of granulocytes and monocytes, T helper 1/T helper 2 cytokines, and serum oxygen radical absorbance capacity.

Results:

The preparation was found to be safe over the 4 weeks at both doses tested. There were no clinically relevant changes to blood measurements of hemopoietic, hepatic, or renal function. Immunomodulatory measurements showed no dose response between the two doses. The combined results from the two doses demonstrated a significant increase in cytotoxic T cell numbers and phagocytic capacity in monocytes, and a significant decrease in levels of the inflammatory cytokine interleukin 6. A separate analysis of the 100 mg dose (n = 5) alone showed a significant linear component over time (P < 0.05) for phagocytosis by both granulocytes and monocytes.

Conclusion:

The seaweed nutrient complex was safe to use when taken orally over 4 weeks. The preparation was demonstrated to have potential as an immune modulator, and this bioactivity deserves further exploration.

Potential role of marine algae on female health, beauty, and longevity

Marine environment has been known as a rich source of chemical structures with numerous health benefit effects. Among marine organisms, marine algae have been identified as an underexploited plant resource although they have long been recognized as valuable sources of structurally diverse bioactive compounds. Presently, several lines of studies have provided insight into biological activities of marine algae in promoting female health, beauty, and longevity. Hence, marine algae have a great potential to be used as a part of pharmaceuticals, nutraceuticals, and functional foods. This contribution presents an overview of marine algal potential effect in promoting female health, beauty, and longevity.

Influence of laminarin polysaccahrides on oxidative damage

Laminarin is a tropical plant traditionally used in Chinese medicine. In this experiment, Laminarin polysaccharides were analysed using GC-MS method and result showed that the polysaccharides contained mannose (3.27%), arabinose (8.61%), glucose (4.23%), galactose (12.12%), fucose (46.93%). Laminarin polysaccharides were tested to evaluate their effect on lung oxidative stress and lipid peroxidation in rats. The animal were divided into model and polysaccharides-treated animal. Laminarin polysaccharides were administered by gavage over a 14-day period. The results indicated that Laminarin polysaccharides significantly normalized catalase (CAT) activity (P<0.01), increased glutathione peroxidase (GPx) activity (P<0.05), superoxide dismutase (SOD) activity and reduced malondialdehyde (MDA) concentrations in animal. It could be concluded that Laminarin polysaccharides appeared to be more effective in reducing sepsis-induced oxidative stress, lipid peroxidation in animal.