Medicinal Plant Leaf Extract From Sage and Lemon Verbena Promotes Intestinal Immunity and Barrier Function in Gilthead Seabream (Sparus aurata)

Abstract

The inclusion of a medicinal plant leaf extract (MPLE) from sage (Salvia officinalis) and lemon verbena (Lippia citriodora), rich in verbascoside and triterpenic compounds like ursolic acid, was evaluated in gilthead seabream (Sparus aurata) fed a low fishmeal-based diet (48% crude protein, 17% crude fat, 21.7 MJ kg-1, 7% fishmeal, 15% fish oil) for 92 days. In particular, the study focused on the effect of these phytogenic compounds on the gut condition by analyzing the transcriptomic profiling (microarray analysis) and histological structure of the intestinal mucosa, as well as the histochemical properties of mucins stored in goblet cells. A total number of 506 differentially expressed genes (285 up- and 221 down-regulated) were found when comparing the transcriptomic profiling of the intestine from fish fed the control and MPLE diets. The gut transcripteractome revealed an expression profile that favored biological mechanisms associated to the 1) immune system, particularly involving T cell activation and differentiation, 2) gut integrity (i.e., adherens and tight junctions) and cellular proliferation, and 3) cellular proteolytic pathways. The histological analysis showed that the MPLE dietary supplementation promoted an increase in the number of intestinal goblet cells and modified the composition of mucins’ glycoproteins stored in goblet cells, with an increase in the staining intensity of neutral mucins, as well as in mucins rich in carboxylated and weakly sulfated glycoconjugates, particularly those rich in sialic acid residues. The integration of transcriptomic and histological results showed that the evaluated MPLE from sage and lemon verbena is responsible for the maintenance of intestinal health, supporting gut homeostasis and increasing the integrity of the intestinal epithelium, which suggests that this phytogenic may be considered as a promising sustainable functional additive for aquafeeds.

Spray-Dried Porcine Plasma Promotes the Association Between Metabolic and Immunological Processes at Transcriptional Level in Gilthead Sea Bream (Sparus aurata) Gut

“…In the present study, we evaluated the potential benefits of the dietary administration of SDPP in the gut of a marine teleost species by a detailed transcripteractome built from the enriched biological processes obtained to elucidate how this functional ingredient acted upon the maintenance of the gut mucosal tissue. Transcripteractome-based functional network analysis on teleost fish has gained attention in the last years (Firmino et al, 2020(Firmino et al, , 2021aReyes-López et al, 2021;Salomón et al, 2021). Previously, a similar strategy was followed by Reyes-López et al (2021) to analyze the effects of SDPP at skin level.…”

“…A small piece of the anterior intestine (0.5 cm) was dissected and immediately transferred into RNAlater (Ambion R ) incubated at 4 • C overnight and frozen at −80 • C until further RNA extraction. The anterior intestine was chosen because of its immunological relevance in comparison with other intestinal sections (Oehlers et al, 2011;Salomón et al, 2021). Fish growth and feed utilization from Control and SDPP groups were evaluated using the following indices: Fulton's condition factor (K) = (BW/SL 3 ) × 100; specific growth rate in BW (SGR,%) = [(ln BWf −ln BWi) × 100]/time (d) and feed conversion ratio (FCR, g/g) = FI/(Bf −Bi), where FI was the total feed intake during the experimental period (g) and, Bi and Bf were the initial and final biomass (g), respectively.…”

“…In fish, the intestine is a complex multifunctional organ with critical physiological roles, including water and electrolyte homeostasis, endocrine modulation, metabolism and immune regulation, and commensal microbiota balance (Salinas and Parra, 2015;Khansari et al, 2018;Firmino et al, 2021c;Salomón et al, 2021). Notably, the intestine is one of the leading portals of pathogens' entry into the organism.…”

“…Furthermore, the aquaculture industry has developed functional feeds to improve growth, immune response; physiological functions, and health performance in fishes that promote specific benefits to the host beyond the primary nutritional requirement. Functional feed additives include prebiotics, probiotics, vitamins, minerals, and plant, animal, or algae extracts (Parra et al, 2015;Salinas and Parra, 2015;Khansari et al, 2018;Salomón et al, 2021). The spray-dried porcine plasma (SDPP) is an abattoir by-product used in animal nutrition due to its excellent amino acid profile and digestibility close to 99% (Bureau et al, 1999).…”

Phytogenics From Sage and Lemon Verbena Promote Growth, Systemic Immunity and Disease Resistance in Atlantic Salmon (Salmo salar)

“…These functional properties make them very attractive for the industry as potential prophylactic dietary treatments. In particular, the current investigation endeavors to explore the dietary effects of phytogenics derived from a mixture of medicinal plants, the sage (Salvia officinalis, Lamiaceae) and the lemon verbena (Lippia citriodora, Verbenaceae), both recognized for their health and growth-promoting properties for aquatic species (Elumalai et al, 2020;Salomón et al, 2020Salomón et al, , 2021a. In particular, in a previous study from our group, we showed that a medicinal plant leaf extract (MPLE) from sage and lemon verbena promoted an improvement in the classical key performance indicators (KPIs) linked to somatic growth and feed efficiency.…”