In vitro sponge fragment culture of Chondrosia reniformis (Nardo, 1847).
ABSTRACT In vitro cultivation systems for sponges (Porifera) have to be developed to produce compounds of value in biotechnological processes. Organotypic culture attempts, which maintain or mimic the natural tissue structure, are promising ways towards a biotechnology of sponges. We used the Mediterranean species Chondrosia reniformis for sponge fragment in vitro cultivation. The species is common throughout the Mediterranean, easy to keep in aquariums and shows good recovery and regeneration after fragmentation. The regeneration process of the 50-80 mm(3) fragments lasted for several days and resulted in a rounded or ovoid body shape. The aquiferous system was reduced. Cells performed proliferation during the first weeks as we could demonstrate by 5-bromo-2'-deoxy-uridine (BrdU) incorporation. No proliferation could be demonstrated after a culture period of 3 months, but silicate uptake. Cellular density decreased with cultivation length, but collagen production increased. Fragments have been kept in culture up to 19 months. C. reniformis can be used as a model system to develop feeding strategies and evaluate the biotechnological potential of sponge fragment in vitro cultivation.
Article: Neuroactive substances specifically modulate rhythmic body contractions in the nerveless metazoon Tethya wilhelma (Demospongiae, Porifera).[show abstract] [hide abstract]
ABSTRACT: Sponges (Porifera) are nerve- and muscleless metazoa, but display coordinated motor reactions. Therefore, they represent a valuable phylum to investigate coordination systems, which evolved in a hypothetical Urmetazoon prior to the central nervous system (CNS) of later metazoa. We have chosen the contractile and locomotive species Tethya wilhelma (Demospongiae, Hadromerida) as a model system for our research, using quantitative analysis based on digital time lapse imaging. In order to evaluate candidate coordination pathways, we extracorporeally tested a number of chemical messengers, agonists and antagonists known from chemical signalling pathways in animals with CNS. Sponge body contraction of T. wilhelma was induced by caffeine, glycine, serotonine, nitric oxide (NO) and extracellular cyclic adenosine monophosphate (cAMP). The induction by glycine and cAMP followed patterns varying from other substances. Induction by cAMP was delayed, while glycine lead to a bi-phasic contraction response. The frequency of the endogenous contraction rhythm of T. wilhelma was significantly decreased by adrenaline and NO, with the same tendency for cAMP and acetylcholine. In contrast, caffeine and glycine increased the contraction frequency. The endogenous rhythm appeared irregular during application of caffeine, adrenaline, NO and cAMP. Caffeine, glycine and NO attenuated the contraction amplitude. All effects on the endogenous rhythm were neutralised by the washout of the substances from the experimental reactor system. Our study demonstrates that a number of chemical messengers, agonists and antagonists induce contraction and/or modulate the endogenous contraction rhythm and amplitude of our nerveless model metazoon T. wilhelma. We conclude that a relatively complex system of chemical messengers regulates the contraction behaviour through auto- and paracrine signalling, which is presented in a hypothetical model. We assume that adrenergic, adenosynergic and glycinergic pathways, as well as pathways based on NO and extracellular cAMP are candidates for the regulation and timing of the endogenous contraction rhythm within pacemaker cells, while GABA, glutamate and serotonine are candidates for the direct coordination of the contractile cells.Frontiers in Zoology 02/2006; 3:7. · 4.46 Impact Factor