Effect of fasting and refeeding on in vitro muscle cell proliferation in rainbow trout ( Oncorhynchus mykiss )

Abstract

The effects of short-term fasting and refeeding were studied on satellite cells extracted from white epaxial muscle of juvenile rainbow trout (1-3 g body weight). In vitro changes in the proliferation of satellite cells were analyzed using bromodeoxyuridine (BrdU) incorporation over a 24-h period. Proliferation in fed control fish was characterized by an initial basal proliferation rate of 5-10% BrdU-labeled nuclei x day(-1), followed by an exponential increase at a rate of +18-20% x day(-1), up to a maximum of 60-70% BrdU-labeled nuclei x day(-1). Characteristics of satellite cells extracted from starved fish, namely extraction yield, morphology, and proliferation, were different from those of fed fish. Fasting (8-10 days) completely suppressed initial proliferation of satellite cells in vitro over a period of 4 days. After this delay, proliferation resumed and changes in proliferation rates over time were similar to those of the control group. In fish fed for 4 days after an 8-day fast, the initial proliferation rate and the changes in proliferation rates over time were completely restored. These findings demonstrate that satellite cells express different behavior depending on feeding status, which could be due to the presence of different satellite cell populations.

In vitro and ex vivo models indicate that the molecular clock in fast skeletal muscle of Atlantic cod is not autonomous

“…Atlantic cod myosatellite cells were able to proliferate and differentiate in vitro. The morphological characteristics of Atlantic cod satellite cells were similar to the reported features found in other teleosts species, particularly their spindle-shape morphology [21,22,28,29]. The observed irregular shape of some satellite cells at the early days of culture could have been due to the enzymatic digestion and mesh passages.…”

Expression of rainbow trout glucose transporters GLUT1 and GLUT4 during in vitro muscle cell differentiation and regulation by insulin and IGF-I

“…For this purpose we used a well-characterized primary culture of trout skeletal muscle cells (10,15,36,37) that provides a useful tool to reproduce the muscle differentiation process in vitro and study the biology of fish muscle cells. Importantly, trout muscle cells have receptors for insulin and IGF-I and IGF-I binding has been shown to gradually increase during myogenesis (10,33).…”

“…Animals (40 to 80 for each isolation) were killed by a blow to the head and immersed in 70% ethanol for 30 s to sterilize external surfaces. Muscle satellite cells from rainbow trout were isolated and cultured following a protocol previously described (10,15), with some modifications. Briefly, after removal of the skin, dorsal white muscle was isolated in sterile conditions and collected in DMEM containing 9 mM NaHCO 3, 20 mM HEPES, 15% horse serum, and antibiotic-antimycotic cocktail (100 U/ml penicillin, 100 g/ml streptomycin, 25 g/ml amphotericin B, 75 g/ml gentamycin) at pH 7.4.…”

Myostatin inhibits myosatellite cell proliferation and consequently activates differentiation: evidence for endocrine-regulated transcript processing

“…Unlike birds and mammals, however, where muscle hyperplasia stops after birth, both hyperplastic and hypertrophic growth occurs in fish muscle (Mommsen 2001). Indeed, bony fish are a rich source of primary myosatellite cells, and, in contrast to mammals, these cells are easily obtained from rainbow trout and at comparatively much higher titers (Alfei et al 1989, Koumans et al 1991a,b, 1993, Fauconneau & Paboeuf 2000, 2001, Mommsen 2001, Castillo et al 2002. A better understanding of this unique phenomenon will, therefore, help explain myogenesis in fish.…”