‘Fish matters’: the relevance of fish skin biology to investigative dermatology

Abstract

Fish skin is a multi-purpose tissue that serves numerous vital functions including chemical and physical protection, sensory activity, behavioural purposes or hormone metabolism. Further, it is an important first-line defense system against pathogens, as fish are continuously exposed to multiple microbial challenges in their aquatic habitat. Fish skin excels in highly developed antimicrobial features, many of which have been preserved throughout evolution, and infection defense principles employed by piscine skin are still operative in human skin. This review argues that it is both rewarding and important for investigative dermatologists to revive their interest in fish skin biology, as it provides insights into numerous fundamental issues that are of major relevance to mammalian skin. The basic molecular insights provided by zebrafish in vivo-genomics for genetic, regeneration and melanoma research, the complex antimicrobial defense systems of fish skin and the molecular controls of melanocyte stem cells are just some of the fascinating examples that illustrate the multiple potential uses of fish skin models in investigative dermatology. We synthesize the essentials of fish skin biology and highlight selected aspects that are of particular comparative interest to basic and clinically applied human skin research.

Molecular characterization and expression pattern of c-type and g-type lysozyme isoforms in starry flounder Platichthys stellate infected with Streptococcus parauberis

“…In the present species, the lysozyme activity level in mucus was consistently higher than that in serum, both in non-challenged and bacteria-challenged groups. This observation is well in agreement with previous reports that lysozyme content in the skin mucus is more abundant than in blood, probably relating to the anti-infection potential of fish mucus as the primary defense [51][52][53][54]. However, under nonstimulated condition, the enzyme activity in the skin is the reverse condition of the expression pattern of lysozyme transcripts in the present species.…”

The Skin Microbiome of <i>Gambusia affinis</i> Is Defined and Selective

“…Studies such as these may provide important contributions to human health, as fish skin biology has been studied as a model for human dermatology, especially related to innate antimicrobial functions [7]. Additionally, fish skin is an excellent general model for mucosal immunity, as fishes live in aquatic environments in constant exposure to high numbers and varieties of microbes.…”

Gene expression profiling in the skin of zebrafish infected with Citrobacter freundii

“…Cytokines act in the local signaling network of considerable importance for the initiation, effectuation and modulation of skin immune responses [5,6]. Unlike that of higher vertebrates, fish skin is not keratinized and is more susceptible to infection [7]. It is the most common site of colonization and infection for pathogens, especially under intensive aquaculture conditions.…”