ABSTRACT
The present studies were conducted to investigate the changes in lipid and fatty acid composition during the earliest stages of somatic embryogenesis in leaf tissues of the Cichorium hybrid '474'. The presence of glycerol in the culture medium during the induction step allowed to separate two phases in the embryogenic process. Firstly, cells are induced for morphogenetic competence (induction phase) and secondly, they express an embryogenic competence (expression phase). The analysis of fatty acid composition of total lipids showed that the percentage of linolenic acid (18:3) decreased while that of linoleic acid (18:2) increased throughout the culture period. A comparison with a non-embryogenic genotype of Cichorium indicated a higher increase of linoleate content in embryogenic genotype. The incorporation of [14C] glycerol into lipid classes was studied in leaf tissues. During the induction step, label was confined almost exclusively in polar lipids, particularly in phosphatidylcholine (PC). An important increase of labeled triacylglycerols (TAG) amounts was noted during the expression step. The accumulation of 18:2 was observed in PC and also in TAG. These results show that the early stages of somatic embryogenesis are associated with the increase of PC and TAG which are mainly enriched in 18:2.
Subject(s)
Anthraquinones/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Osteoarthritis/drug therapy , Animals , Cartilage/enzymology , Collagenases/analysis , Contusions/complications , Disease Models, Animal , Osteoarthritis/enzymology , Osteoarthritis/etiology , Osteoarthritis/pathology , RabbitsABSTRACT
A method has been developed for the direct extraction of collagenase from small quantities (5 mg) of human osteoarthritic articular cartilage. The enzyme, which was not detected in normal cartilage, was entirely in a latent form and demonstrated typical properties of mammalian collagenase after activation by trypsin.
Subject(s)
Cartilage, Articular/enzymology , Microbial Collagenase/analysis , Osteoarthritis/enzymology , Animals , Electrophoresis, Polyacrylamide Gel , Enzyme Activation/drug effects , Humans , Hydrogen-Ion Concentration , Male , Mice , Octoxynol , Polyethylene Glycols/pharmacology , Trypsin/pharmacologyABSTRACT
A contusive procedure has been developed for the induction of a predictable and reproducible degenerative joint disease in knees of rabbits. Significant degeneration was observed in patella, condyles, and trochlea. These lesions included fibrillation, ulceration and erosion, clones of chondrocytes, and osteophyte formation. The incidence and distribution of lesions with time following contusion were also investigated. Lesions were observed as early as 1 day post-contusion and increased in number and severity. A global scoring system has been devised to permit comparisons of lesion incidence and severity, specially to test drug efficacy in this model of osteoarthritis.