Sea cucumber body wall contains several naturally occurring bioactive components that possess health-promoting properties. Isostichopus badionotus from Yucatan, Mexico is heavily fished, but little is known about its bioactive constituents. We previously established that I. badionotus meal had potent anti-inflammatory properties in vivo. We have now screened some of its constituents for anti-inflammatory activity in vitro. Glycosaminoglycan and soluble protein preparations reduced 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammatory responses in HaCaT cells while an ethanol extract had a limited effect. The primary glycosaminoglycan (fucosylated chondroitin sulfate; FCS) was purified and tested for anti-inflammatory activity in vivo. FCS modulated the expression of critical genes, including NF-ĸB, TNFα, iNOS, and COX-2, and attenuated inflammation and tissue damage caused by TPA in a mouse ear inflammation model. It also mitigated colonic colitis caused in mice by dextran sodium sulfate. FCS from I. badionotus of the Yucatan Peninsula thus had strong anti-inflammatory properties in vivo.

Crohn’s Disease (CD) and Ulcerative Colitis (UC) are world-wide health problems in which intestinal dysbiosis or adverse functional changes in the microbiome are causative or exacerbating factors. The reduced abundance and diversity of the microbiome may be a result of a lack of exposure to vital commensal microbes or overexposure to competitive pathobionts during early life. Alternatively, many commensal bacteria may not find a suitable intestinal niche or fail to proliferate or function in a protective/competitive manner if they do colonize. Bacteria express a range of factors, such as fimbriae, flagella, and secretory compounds that enable them to attach to the gut, modulate metabolism, and outcompete other species. However, the host also releases factors, such as secretory IgA, antimicrobial factors, hormones, and mucins, which can prevent or regulate bacterial interactions with the gut or disable the bacterium. The delicate balance between these competing host and bacteria factors dictates whether a bacterium can colonize, proliferate or function in the intestine. Impaired functioning of NOD2 in Paneth cells and disrupted colonic mucus production are exacerbating features of CD and UC, respectively, that contribute to dysbiosis. This review evaluates the roles of these and other the host, bacterial and environmental factors in inflammatory bowel diseases.

Low-molecular-weight peptides derived from the digestion of body wall proteins in some sea cucumber species have wound-healing and health-promoting properties, but their potency varies widely by species, growth environment, age, and season. For the first time, small peptide (1–3 kDa) fractions have been isolated from the whole-body wall of the sea cucumber Isostichopus badionotus and its constituent collagen and tested for wound healing capacity in vitro. Ultrafiltered digests (1–3 kDa) of the pure collagen, as well as 1–3 kDa digests of the whole-body wall, had potent antioxidant activities and promoted rapid wound healing in a keratinocyte scratch wound assay. Gene expression studies suggested that the wound-healing actions of the individual collagen and body wall 1–3 kDa fractions differed significantly. Low-molecular-weight peptides derived from I. badionotus collagen did promote wound healing in vitro; however, their efficacy may have been modulated by additional factors produced during body wall or collagen digestion. These findings need to be confirmed in vivo.

Overfishing of sea cucumber Isostichopus badionotus from Yucatan has led to a major population decline. They are being captured as an alternative to traditional species despite a paucity of information about their health-promoting properties. The transcriptome of the body wall of wild and farmed I. badionotus has now been studied for the first time by an RNA-Seq approach. The functional profile of wild I. badionotus was comparable with data in the literature for other regularly captured species. In contrast, the metabolism of first generation farmed I. badionotus was impaired. This had multiple possible causes including a sub-optimal growth environment and impaired nutrient utilization. Several key metabolic pathways that are important in effective handling and accretion of nutrients and energy, or clearance of harmful cellular metabolites, were disrupted or dysregulated. For instance, collagen mRNAs were greatly reduced and deposition of collagen proteins impaired. Wild I. badionotus is, therefore, a suitable alternative to other widely used species but, at present, the potential of farmed I. badionotus is unclear. The environmental or nutritional factors responsible for their impaired function in culture remain unknown, but the present data gives useful pointers to the underlying problems associated with their aquaculture.