Teleost fishes represent a highly diverse group
consisting of more than 20,000 species living across all
aquatic environments. This group has significant economical, societal and environmental impacts, yet research efforts
have concentrated primarily on salmonid and cyprinid species. This review examines carbohydrate/glucose metabolism and its regulation in these model species including the
role of hormones and diet. Over the past decade, molecular
tools have been used to address some of the downstream
components of these processes and these are incorporated to
better understand the roles played by carbohydrates and their
regulatory paths. Glucose metabolism remains a contentious
area as many fish species are traditionally considered glucose
intolerant and, therefore, one might expect that the use and
storage of glucose would be considered of minor importance.
However, the actual picture is not so clear since the apparent
intolerance of fish to carbohydrates is not evident in herbivorous and omnivorous species and even in carnivorous
species, glucose is important for specific tissues and/or for
specific activities. Thus, our aim is to up-date carbohydrate
metabolism in fish, placing it to the context of these new
experimental tools and its relationship to dietary intake.
Finally, we suggest that new research directions ultimately
will lead to a better understanding of these processes.