Antioxidant and Anti-Inflammatory Activities of Sargassum macrocarpum Extracts.

Oxidative stress and the inflammatory response are known to be the most important pathological factors for aging skin cells. Therefore, substances that protect skin cells from oxidative stress and inflammatory reactions of the skin have potential as functional ingredients for skin care. In the present study, we investigated the potential of Sargassum macrocarpum as an anti-inflammatory candidate for inflammatory skin disease. Antioxidant and anti-inflammatory activities are desirable properties in such functional materials. The total polyphenol content as well as antioxidant and anti-inflammatory activities were evaluated in hot-water (HES) and ethanol (EES) extracts of S. macrocarpum. The polyphenol content was higher in the HES (HES: 115.9 ± 15.3 mg GA/g, EES: 3.9 ± 0.5 mg GA/g), and the HES also had ABTS (HES: IC50 1.0 ± 0.0 mg/mL, EES: IC50 16.09 ± 0.7 mg/mL) and DPPH (HES: IC50 6.50 ± 0.3 mg/mL, EES: IC50 35.3 ± 3.1 mg/mL) radical scavenging capacities as well as FRAP activity (HES: IC50 18.8 ± 0.4 mg/mL, EES: IC50 n.d.). Compared with the EES at the equivalent concentration range (1.25-20 µg/mL), the HES exerted a more potent inhibitory activity on LPS-stimulated nitric oxide (10.3-43.1%), IL-6 (15.7-45.0%), and TNF-α (14.1-20.8%) in RAW 264.7 macrophage cells in addition to TNF-α and IFN-γ-facilitated IL-6 (10.9-84.1%) and IL-8 (7.7-73.2%) in HaCaT keratinocytes. These results suggested that water-soluble materials might be deeply involved in the antioxidant and anti-inflammatory activity in S. macrocarpum. General composition analysis indicated that the HES contains more carbohydrates and polyphenols than the EES, and the monosaccharide composition analysis suggested that fucose-containing sulfated polysaccharide and ß-glucan might be potent anti-inflammatory candidates in the HES. The present study presents important preliminary results and a valuable strategy for developing novel anti-skin dermatitis candidates using a hot-water extract of S. macrocarpum.

Rhamnogalacturonan I-rich polysaccharide isolated from fermented persimmon fruit increases macrophage-stimulatory activity by activating MAPK and NF-κB signaling.

BACKGROUND: Persimmon (Diospyros kaki) is a familiar and widespread fruit, cultivated worldwide. To date, physiological and chemical changes in fermented persimmon fruit and its active compounds have been rarely investigated. Moreover, comparative studies on the pharmacological activities of fermented persimmon fruit-derived compounds have not been reported. RESULTS: To investigate the effect of traditional fermented foods on immunostimulatory activity, non-fermented persimmon fruit (D. kaki, DK) and fermented persimmon fruit (fermented D. kaki, FDK) were prepared and further fractionated into low- and high-molecular weight fractions. FDK exhibited significantly higher activity toward the production of macrophage-stimulatory mediators compared with that of DK, and the high-molecular weight fraction (FDK-H) isolated from FDK was shown to have more potent activity than FDK. FDK-H not only increased the expression of immunostimulatory genes (TNF-α, IL-6, IL-12, and iNOS), but also stimulated the phosphorylation of both MAPK (ERK, JNK, and p38) and NF-κB (p65 and IκB) signaling molecules underlying macrophage activation. The putative chemical characteristic of FDK-H was identified as a pectic rhamnogalacturonan (RG) I-rich polysaccharide with a high molecular weight of 304 kDa containing galacturonic acid, arabinose, rhamnose, and galactose as the major monosaccharide units. CONCLUSION: The present study reveals that traditional fermentation is a useful method for increasing the macrophage-immunostimulatory activity of persimmon fruit, and the increased activity may be associated with structural modification of persimmon polysaccharides. This study may serve to identify a functional ingredient as an immunostimulatory agent, and our results may be applied to develop a new immunostimulatory product using FDK-H. © 2021 Society of Chemical Industry.

Effects of a High-Molecular-Weight Polysaccharides Isolated from Korean Persimmon on the Antioxidant, Anti-Inflammatory, and Antiwrinkle Activity.

Persimmon (Diospyros kaki), a familiar and widespread fruit worldwide, is known to exhibit several physiological effects because of the presence of pharmacologically active compounds called phytochemicals. However, its high-molecular-weight compounds, particularly polysaccharides, have not been extensively studied. In this study, D. kaki extract (DK) was fractionated into low- and high-molecular-weight fractions (DK-L and DK-H, respectively) through ethanol fractionation, and their effects on antioxidant, anti-inflammatory, and antiwrinkle activities were investigated by an in vitro system. DK-H contained significantly higher contents of neutral sugar, uronic acid, and polyphenols compared to DK and DK-L. Furthermore, DK-H exhibited significantly improved pharmacological activities, such as antioxidant, anti-inflammatory, and antiwrinkle properties, compared to those of DK and DK-L, demonstrating that DK-H may play an important role in mediating the beneficial effects of persimmon. Sugar composition analysis and molecular characterization indicated that DK-H consisted of a galacturonic acid (GalA)-rich polysaccharide with a molecular weight of >345 kDa that mainly comprised GalA and small amounts of neutral sugar and polyphenol residues. These results suggest that the bioactive fraction DK-H is likely to be a GalA-rich pectic polysaccharide containing a small number of polyphenol residues, which may be a novel candidate in the pharmaceutical and cosmeceutical industries.

Mitochondrial DNA 4977bp deletion mutation in peripheral blood reflects atrial remodeling in patients with non-valvular atrial fibrillation.

PURPOSE: Recently, mitochondrial DNA 4977bp deletion (mtDNA4977-mut), a somatic mutation related to oxidative stress, has been shown to be associated with atrial fibrillation (AF). We hypothesized that patient age, as well as electroanatomical characteristics of fibrillating left atrial (LA), vary depending on the presence of mtDNA4977-mut in peripheral blood among patients with non-valvular AF. MATERIALS AND METHODS: Analyzing clinical and electroanatomical characteristics, we investigated the presence of the mtDNA4977-mut in peripheral blood of 212 patients (51.1±13.2 years old, 83.5% male) undergoing catheter ablation for non-valvular AF, as well as 212 age-matched control subjects. RESULTS: The overall frequency of peripheral blood mtDNA4977-mut in patients with AF and controls was not significantly different (24.5% vs. 19.3%, p=0.197). When the AF patient group was stratified according to age, mtDNA4977-mut was more common (47.4% vs. 20.0%, p=0.019) in AF patients older than 65 years than their age-matched controls. Among AF patients, those with mtDNA4977-mut were older (58.1±11.9 years old vs. 48.8±11.9 years old, p<0.001). AF patients positive for the mtDNA mutation had greater LA dimension (p=0.014), higher mitral inflow peak velocity (E)/diastolic mitral annular velocity (Em) ratio (p<0.001), as well as lower endocardial voltage (p=0.035), and slower conduction velocity (p=0.048) in the posterior LA than those without the mutation. In multivariate analysis, E/Em ratio was found to be significantly associated with the presence of mtDNA4977-mut in peripheral blood. CONCLUSION: mtDNA4977-mut, an age-related somatic mutation detected in the peripheral blood, is associated with advanced age and electro-anatomical remodeling of the atrium in non-valvular AF.