Sulfated polygalactofucan from triangular sea bell Turbinaria decurrens attenuates inflammatory cytokines on THP-1 human monocytic macrophages.

Inflammation is one of the most significant causes of several chronic diseases, which includes the expression of cytokines activating immune cells to up-regulate the inflammatory cascade. Polysaccharides from marine macroalgae are promising anti-inflammatory agents because of their potential to attenuate inflammatory cytokines. The triangular sea bell Turbinaria decurrens (Sargassaceae) among marine macroalgae is ubiquitous in oceanic waters, and a sulfated polygalactofucan SPTd-2 [→3-(α-L-fucp-(2-OSO3-)-(1 â†’ 4)-α-L-fucp-(3-OAc)-(1 â†’ 4)-ß-D-galp-(1→] was purified from the species. The studied polygalactofucan SPTd-2 exhibited anti-inflammatory activities against cyclooxygenase-2 (IC50 10.56 µM) and 5-lipoxygenase (IC50 3.36 µM) with a greater selectivity index (2.35) than ibuprofen (0.44), besides attenuating pro-inflammatory cytokine production, including tumor necrosis factor-α, transforming growth factor-ß, interleukin-2, 1ß, and interferon-γ. Quantitative real-time polymerase chain reaction displayed that SPTd-2 blocked the mRNA of interferon-γ and interleukin-2, in the human monocytic cell line THP-1. The results showed the potential of SPTd-2 to attenuate inflammation-associated disorders.

Anti-inflammatory decurrencyclics A-B, two undescribed nor-dammarane triterpenes from triangular sea bell Turbinaria decurrens.

Intertidal triangular sea bell Turbinaria decurrens (Bory de Saint-Vincent) (family Sargassaceae) belongs to one of the largely abundant genus of marine brown alga. Bioactivity-directed chromatographic purification of the organic extract of T. decurrens afforded two new nor-dammarane triterpenoids named as decurrencyclic A-B. Decurrencyclic B showed superior attenuation properties against cyclooxygenase-2 (IC50 13.98 µM) and 5-lipoxygenase (IC50 3.02 µM) in contrast with decurrencyclic A. Decurrencyclic B showed higher inhibition potential against COX-2 than that revealed by the anti-inflammatory agent, ibuprofen (IC50 70.44 µM). The higher selectivity index of decurrencyclics (1.39-1.57) acknowledged their selective attenuation property against inducible cyclooxygenase-2. In-silico molecular modeling analysis of decurrencyclic B with the inflammatory enzymes showed least binding energy of -14.55 kcal mol-1. These reports have proven that decurrencyclic B could be a potential therapeutic lead for use against inflammatory pathogenesis.

A novel anti-hyperglycemic sulfated pyruvylated polysaccharide from marine macroalga Hydropuntia edulis.

Dipeptidyl peptidase is a crucial enzyme that regulates glucose metabolism by degrading incretins, such as glucagon-like-peptide-1, thereby reducing insulin secretion from the pancreatic ß-cells. Consequently, dipeptidyl peptidase-IV inhibitors are an important remedial approach to moderate the hyperglycemic pathophysiology. A pyruvylated polysaccharide characterized as [→3)-4,6-O-(1-carboxyethylidene)-ß-D-galp-(2SO3-)-(1→4)-3,6-α-L-AnGalp-(2OMe)-(1→], isolated from the marine macroalga Hydropuntia edulis, showed attenuation potential against dipeptidyl peptidase-IV (IC50 4.44 µM). The structure was elucidated using mass and one/two-dimensional nuclear magnetic resonance spectroscopic analyses of hydrolyzed polysaccharide besides glycosidic linkages obtained from partially methylated alditol acetate derivative. The isolated polysaccharide also revealed potential anti-carbolytic properties against α-amylase/α-glucosidase (IC50 45-47 µM). The results proved the candidacy of pyruvylated polysaccharide isolated from H. edulis as a potential therapeutic lead against hyperglycemia.