Immunomodulatory Activities of Ammodytes personatus Egg Lipid in RAW264.7 Cells

Ammodytes personatus, known as the Pacific sand lance, thrives in cold areas of the North Pacific. In this study, the total lipid was extracted from A. personatus eggs and the fatty acid composition was determined using gas chromatography (GC)–flame ionization detection (FID). The results showed that the extracted lipid contained high content of polyunsaturated fatty acids (PUFAs). The immunomodulatory activities of the A. personatus lipid were investigated using rodent macrophages. First, immune enhancement was analyzed, and the A. personatus lipid significantly and dose-dependently increased the NO production in RAW264.7 cells, and this lipid also regulated the transcription of immune-associated genes in RAW264.7 cells by activating the NF-κB and MAPK pathways. Additionally, flow cytometry revealed that this lipid stimulated phagocytosis. Conversely, the anti-inflammatory activity of the A. personatus lipid was also analyzed and the results showed significantly decreased NO production and gene expression in a dose-dependent manner in LPS-stimulated RAW264.7 cells. In addition, the A. personatus lipid suppressed the LPS-induced phosphorylation of proteins related to the NF-κB and MAPK pathways in LPS-stimulated RAW264.7 cells. Further, flow cytometry demonstrated the lipid-regulated anti-inflammatory activity via inhibition of CD86 expression. The results indicate that A. personatus egg lipid is a potential source of immunomodulation.

Identifying and monitoring of forage fish spawning beaches in British Columbia’s Salish Sea for conservation of forage fish

Pacific sand lance ( Ammodytes personatus) and surf smelt ( Hypomesus pretiosus) are ecologically important forage fish in the marine food webs within the Salish Sea, including British Columbia (BC). Although important, little information exists around the spatiotemporal distribution of these fishes’ beach spawning habitat in the BC Salish Sea. In 2017, the Mount Arrowsmith Biosphere Region Research Institute initiated spawning beach surveys within the Mount Arrowsmith Biosphere Region (MABR). Surveys have geographically expanded along the eastern Vancouver Island coastline between Bowser and Cowichan Bay, BC, including Gabriola Island and Thetis Island. Pacific sand lance embryos have been detected at 17 beaches, with six beaches located within the MABR. Pacific sand lance spawning events have been detected between November and mid-February, with the bulk of embryos detected in November and December. To date, surf smelt embryos have not been detected at the 56 different beaches. These data begin to fill existing data gaps surrounding Pacific sand lance and surf smelt in BC. Furthermore, longer-term data submissions to the Strait of Georgia Data Centre, an open-access database, will provide the necessary data needed to advocate for improved regulatory protections for these ecologically important fish and their spawning habitat.

Sighting rates and prey of Minke Whales (Balaenoptera acutorostrata) and other cetaceans off Cormorant Island, British Columbia

From June to August 2012, we conducted over 500 h of visual surveys from Cormorant Island, British Columbia, to determine behaviour and habitat use patterns of nearby cetaceans. Seven species were documented, but Minke Whales (Balaenoptera acutorostrata) were by far the most common and were observed lunge feeding at the surface on 15 occasions. In addition, this species was documented surface lunge feeding on Pacific Herring (Clupea pallasi) and Pacific Sand Lance (Ammodytes personatus) on 32 occasions during vessel-based cetacean surveys around Cormorant Island between 2010 and 2014. Although Minke Whales are relatively uncommon in British Columbia, these results indicate that they can regularly be found in specific feeding areas during the summer.

Population genetic structure and selective pressure on the mitochondrial ATP6 gene of the Japanese sand lance Ammodytes personatus Girard

Thermoregulation has been suggested to influence mitochondrial DNA (mtDNA) evolution. Previous studies revealed that the mitochondrial protein-coding genes of fish living in temperate climates have smaller dN/dS (Non-synonymous substitution rate/Synonymous substitution rate) than tropical species. However, it is unknown whether different geographic populations of one fish species experience stronger selective pressures between cold and warm climates. The biological characteristics of the Japanese sand lance, Ammodytes personatus in the North-western Pacific is well-suited for assessing the performance of mtDNA evolution among separate geographic populations. In this study, we focused on the mitochondrial ATP6 gene of A. personatus using 174 individuals from eight different sea temperature populations. Two distinct haplotype lineages and a significant population structure (P = 0.016) were found in this species. The frequencies of the two lineages varied with the changes of annual sea temperature. The southern lineage (lineage A, dN/dS = 0.0384) showed a larger dN/dS value than the northern lineage (lineage B, dN/dS = 0.0167), suggesting that sea temperature greatly influences the evolution of the two lineages. The result provides robust evidence of local adaptation between populations in A. personatus.

Thermal adaptation of Japanese sand lance (Ammodytes personatus) in different ocean currents revealed by the cytochrome-b gene

To assess the possible thermal selection on mitochondrial coding genes in cold water species, we explored the population structure of Japanese sand lance (Ammodytes personatus) and performed selection tests on the mitochondrial cytochrome-b gene of species, using 174 individuals from eight different sea temperature populations in different ocean currents. Two distinct haplotype lineages were present in this species, and the lineage frequencies varied with changes in sea temperature. The selection tests showed that A. personatus was subject to purifying selection. Populations living in cold climates had a considerably smaller non-synonymous substitution rate/synonymous substitution rate (dN/dS) than those in temperate areas. The efficiency of the electron transfer chain system may be affected by amino acid changes at codons 353 and 371. These findings provide new evidence that temperature may affect the contemporary distribution of mitochondrial DNA clade frequencies in A. personatus.