Fucoidan aus Braunalgen

2021 ◽  
Vol 53 (04) ◽  
pp. 148-156
Author(s):  
Bettina Hees

ZusammenfassungFucoidan ist ein Polysaccharid, das in Meeresbraunalgen, vor allem der Wakame-Alge, vorkommt. Es ist in vielen Ländern Asiens Bestandteil der täglichen Ernährung mit Algen, darüber hinaus wird es in der traditionellen asiatischen Medizin zur komplementären Behandlung von Tumorerkrankungen eingesetzt. Seit Kurzem ist Fucoidan auch in der EU als „Novel Food“-Lebensmittel bzw. Nahrungsergänzung zugelassen. Fucoidane besitzen eine Vielzahl an antikanzerogenen Wirkungen, was in vitro, in vivo und in klinischen Pilotstudien nachgewiesen werden konnte: Sie reduzieren proinflammatorische Prozesse, können die Proliferation von Krebszellen unterdrücken, aktivieren die Apoptose-Signale von Krebszellen und hemmen die Bildung von vaskulären Wachstumsfaktoren (VEGF), wodurch Angiogenese und Metastasierung unterdrückt werden können. Fucoidan besitzt sowohl systemische Wirkungen – erstmalig nachgewiesen mit Hilfe der microRNA Biomarker-Diagnostik – als auch lokale Wirkungen. Als Biological Response Modifier aktiviert und verbessert Fucoidan die Immunantwort im Darm als First-Line-Abwehr von Tumorzellen und Schlüsselfaktor der Tumorbekämpfung, es wirkt zusätzlich als Booster der natürlichen Killerzellaktivität. Fucoidan kann die Nebenwirkungen von Chemo- und Strahlentherapien reduzieren und es kann die therapeutischen Effekte konventioneller Tumortherapien verbessern. Der Beitrag stellt klinische Ergebnisse zu Fucoidan beim metastasierten Kolonkarzinom sowie bei Brustkrebs vor.

Vaccines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 811
Author(s):  
Diego Giampietro Peroni ◽  
Lorenzo Morelli

Background. It has been recognized that microbiota plays a key role in shaping immune system maturation and activity. Since probiotic administration influences the microbiota composition and acts as a biological response modifier, the efficacy of an adjuvant for boosting vaccine-specific immunity is investigated. Methods. A review of the literature was performed, starting from the mechanisms to laboratory and clinical evidence. Results. The mechanisms, and in vitro and animal models provide biological plausibility for microbiota use. Probiotics have been investigated as adjuvants in farm conditions and as models to understand their potential in human vaccinations with promising results. In human studies, although probiotics were effective in ameliorating seroconversion to vaccines for influenza, rotavirus and other micro-organisms, the results for clinical use are still controversial, especially in particular settings, such as during the last trimester of pregnancy. Conclusion. Although this topic remains controversial, the use of probiotics as adjuvant factors in vaccination represents a strategic key for different applications. The available data are deeply influenced by heterogeneity among studies in terms of strains, timing and duration of administration, and patients. Although these do not allow us to draw definitive conclusions, probiotics as adjuvants in vaccination should be considered in future studies, especially in the elderly and in children, where vaccine effectiveness and duration of immunization really matter.


1987 ◽  
Vol 149 (2) ◽  
pp. 562-567 ◽  
Author(s):  
Kunitaka Hirose ◽  
Michinori Hakozaki ◽  
Junji Kakuchi ◽  
Kenichi Matsunaga ◽  
Chikao Yoshikumi ◽  
...  

2021 ◽  
Vol 12 ◽  
Author(s):  
Lawrence A. Potempa ◽  
Ibraheem M. Rajab ◽  
Margaret E. Olson ◽  
Peter C. Hart

C-reactive protein (CRP) was first recognized in the 1940s as a protein that appeared in blood during acute episodes of infectious disease. Its presence and pharmacodynamics were found in essentially all diseases that involved tissue damage and inflammation. Identified as a major component of the innate, unlearned immunity, it became a useful diagnostic marker for the extent of inflammation during disease exacerbation or remission. Efforts to define its true biological role has eluded clear definition for over a half-century. Herein, a unifying concept is presented that explains both pro-inflammatory and anti-inflammatory activities of CRP. This concept involves the recognition and understanding that CRP can be induced to undergo a pronounced, non-proteolytic reorganization of its higher-level protein structures into conformationally distinct isomers with distinctive functional activities. This process occurs when the non-covalently associated globular subunits of the pentameric isoform (“pCRP”) are induced to dissociate into a monomeric isoform (“mCRP”). mCRP consistently and potently provides pro-inflammatory activation and amplification activities. pCRP provides weak anti-inflammatory activities consistent with low-level chronic inflammation. mCRP can spontaneously form in purified pCRP reagents in ways that are not immediately recognized during purification and certification analyses. By now understanding the factors that influence pCRP dissociate into mCRP, many published reports investigating CRP as a biological response modifier of host defense can be reevaluated to include a discussion of how each CRP isoform may have affected the generated results. Specific attention is given to in vitro and in vivo studies of CRP as an anti-cancer agent.


Oncogene ◽  
2021 ◽  
Author(s):  
Jian Chen ◽  
Risi Na ◽  
Chao Xiao ◽  
Xiao Wang ◽  
Yupeng Wang ◽  
...  

Abstract5-Fluorouracil (5-FU)-based chemotherapy is the first-line treatment for colorectal cancer (CRC) but is hampered by chemoresistance. Despite its impact on patient survival, the mechanism underlying chemoresistance against 5-FU remains poorly understood. Here, we identified serine hydroxymethyltransferase-2 (SHMT2) as a critical regulator of 5-FU chemoresistance in CRC. SHMT2 inhibits autophagy by binding cytosolic p53 instead of metabolism. SHMT2 prevents cytosolic p53 degradation by inhibiting the binding of p53 and HDM2. Under 5-FU treatment, SHMT2 depletion promotes autophagy and inhibits apoptosis. Autophagy inhibitors decrease low SHMT2-induced 5-FU resistance in vitro and in vivo. Finally, the lethality of 5-FU treatment to CRC cells was enhanced by treatment with the autophagy inhibitor chloroquine in patient-derived and CRC cell xenograft models. Taken together, our findings indicate that autophagy induced by low SHMT2 levels mediates 5-FU resistance in CRC. These results reveal the SHMT2–p53 interaction as a novel therapeutic target and provide a potential opportunity to reduce chemoresistance.


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