Antarctic Marine Algae Extracts as a Potential Natural Resource to Protect Epithelial Barrier Integrity

Abstract

The intestine and skin provide crucial protection against the external environment. Strengthening the epithelial barrier function of these organs is critical for maintaining homeostasis against inflammatory stimuli. Recent studies suggest that polar marine algae are a promising bioactive resource because of their adaptation to extreme environments. To investigate the bioactive properties of polar marine algae on epithelial cells of the intestine and skin, we created extracts of the Antarctic macroalgae Himantothallus grandifolius, Plocamium cartilagineum, Phaeurus antarcticus, and Kallymenia antarctica, analyzed the compound profiles of the extracts using gas chromatography-mass spectrometry, and tested the protective activities of the extracts on human intestinal and keratinocyte cell lines by measuring cell viability and reactive oxygen species scavenging. In addition, we assessed immune responses modulated by the extracts by real-time polymerase chain reaction, and we monitored the barrier-protective activities of the extracts on intestinal and keratinocyte cell lines by measuring transepithelial electrical resistance and fluorescence-labeled dextran flux, respectively. We identified bioactive compounds, including several fatty acids and lipid compounds, in the extracts, and found that the extracts perform antioxidant activities that remove intracellular reactive oxygen species and scavenge specific radicals. Furthermore, the Antarctic marine algae extracts increased cell viability, protected cells against inflammatory stimulation, and increased the barrier integrity of cells damaged by lipopolysaccharide or ultraviolet radiation. These results suggest that Antarctic marine algae have optimized their composition for polar environments, and furthermore, that the bioactive properties of compounds produced by Antarctic marine algae can potentially be used to develop therapeutics to promote the protective barrier function of the intestine and skin.

Polar microalgae extracts protect human HaCaT keratinocytes from damaging stimuli and ameliorate psoriatic skin inflammation in mice

“…HaCaT cells were seeded on tissue culture polycarbonate membrane filters (pore size, 0.4 μm) in 24-well transwell plates (SPL Life Sciences, Gyeonggi-do, Korea) at a seeding density of 1.0 × 10 5 cells/cm 2 . Epithelial permeability across HaCaT monolayers was assessed by measuring the flux of 4-kDa FITC-labeled dextran (2 mg/mL) (Sigma–Aldrich) from the apical chamber to the basolateral chamber of the transwells [ 9 ]. FITC-dextran was added to the apical chamber and incubated for 2 h at 37 °C.…”

“…To sustain growth at low temperatures, polar organisms acquire metabolic, structural, and functional adaptations [ 8 ]. Thus, natural products synthesized by polar organisms may offer advantages for protecting against environmental challenges [ 9 ]. Microalgae are photosynthetic eukaryotes that make up a significant portion of marine and freshwater phytoplankton and have a long history of evolutionary and adaptive diversification to various habitats and extreme polar environmental gradients [ 7 , 10 ].…”

Microalgae from Cold Environments and Their Possible Biotechnological Applications

“…Recently, Ko et al [ 39 ] demonstrated the bioactive properties of four Arctic algal extracts, the brown algae Himantothallus grandifolius and Phaeurus antarcticus and the red algae Plocamium cartilagineum and Trematocarpus antarcticus (former Kallymenia antarctica ), on epithelial cells of human intestine and skin. Antarctic marine microalgal methanolic extracts increased cell viability of human colorectal adenocarcinoma cells Caco-2 and immortalized human keratinocyte HaCaT cells, protected cells against inflammatory stimulation, and increased the barrier integrity of cells damaged by lipopolysaccharide or ultraviolet radiation.…”

“…Antarctic marine microalgal methanolic extracts increased cell viability of human colorectal adenocarcinoma cells Caco-2 and immortalized human keratinocyte HaCaT cells, protected cells against inflammatory stimulation, and increased the barrier integrity of cells damaged by lipopolysaccharide or ultraviolet radiation. The authors suggested that Antarctic marine microalgae extracts rich in fatty acids and lipids may, due to adaptation to the extreme polar environment, exert scavenging activity against specific radicals and intracellular reactive oxygen species (ROS) [ 39 ]. In 2023, León-Vaz et al [ 34 ] explored the ability of nineteen strains of Nordic microalgae (green algae) to produce bioactive compounds: Chlorococcum sp.…”

Annotation of GC‐MS Data of Antimicrobial Constituents in the Antarctic Seaweed Phaeurus antarcticus by Molecular Networking

“…The macroalga Phaeurus antarcticus Skottsberg (Phaeophyceae) is endemic to Antarctic and sub‐Antarctic regions [16] . This species remains underexplored in terms of its chemical and biological activity profiles, with a limited number of reports related to its polyphenol and lipid contents [17–19] . Therefore, this study aimed to evaluate the biological activities of P. antarcticus towards pathogenic bacteria, and parasites such as Leishmania amazonensis , Neospora caninum , and, the enzyme HRP, targeting its bioactive compounds by coupling GC‐MS molecular networking to multivariate analysis.…”