ABSTRACT
BACKGROUND: Snakes belonging to the Bothrops genus are vastly distributed in Central and South America and are responsible for most cases of reported snake bites in Latin America. The clinical manifestations of the envenomation caused by this genus are due to three major activities-proteolytic, hemorrhagic and coagulant-mediated by metalloproteinases, serine proteinases, phospholipases A2 and other toxic compounds present in snake venom. Interestingly, it was observed that snakes are resistant to the toxic effects of its own and other snake's venoms. This natural immunity may occur due the absence of toxin target or the presence of molecules in the snake plasma able to neutralize such toxins. METHODS: In order to identify anti-venom molecules, we construct a cDNA library from the liver of B. jararaca snakes. Moreover, we analyzed the expression profile of four molecules-the already known anti-hemorrhagic factor Bj46a, one gamma-phospholipase A2 inhibitor, one inter-alpha inhibitor and one C1 plasma protease inhibitor-in the liver of juvenile and adult snakes by qPCR. RESULTS: The results revealed a 30-fold increase of gamma-phospholipase A2 inhibitor and a minor increase of the inter-alpha inhibitor (5-fold) and of the C1 inhibitor (3-fold) in adults. However, the Bj46a factor seems to be equally transcribed in adults and juveniles. DISCUSSION: The results suggest the up-regulation of different inhibitors observed in the adult snakes might be a physiological adaptation to the recurrent contact with their own and even other snake's venoms throughout its lifespan. This is the first comparative analysis of ontogenetic variation of expression profiles of plasmatic proteins with potential anti-venom activities of the venomous snake B. jararaca. Furthermore, the present data contributes to the understanding of the natural resistance described in these snakes.
ABSTRACT
Background. Snakes belonging to the Bothrops genus are vastly distributed in Central and South America and are responsible for most cases of reported snake bites in Latin America. The clinical manifestations of the envenomation caused by this genus are due to three major activities-proteolytic, hemorrhagic and coagulant-mediated by metalloproteinases, serine proteinases, phospholipases A(2) and other toxic compounds present in snake venom. Interestingly, it was observed that snakes are resistant to the toxic effects of its own and other snake's venoms. This natural immunity may occur due the absence of toxin target or the presence of molecules in the snake plasma able to neutralize such toxins. Methods. In order to identify anti-venom molecules, we construct a cDNA library from the liver of B. jararaca snakes. Moreover, we analyzed the expression profile of four molecules-the already known anti-hemorrhagic factor Bj46a, one gamma-phospholipase A(2) inhibitor, one inter-alpha inhibitor and one C1 plasma protease inhibitor-in the liver of juvenile and adult snakes by qPCR. Results. The results revealed a 30-fold increase of gamma-phospholipase A(2) inhibitor and a minor increase of the inter-alpha inhibitor (5-fold) and of the C1 inhibitor (3-fold) in adults. However, the Bj46a factor seems to be equally transcribed in adults and juveniles. Discussion. The results suggest the up-regulation of different inhibitors observed in the adult snakes might be a physiological adaptation to the recurrent contact with their own and even other snake's venoms throughout its lifespan. This is the first comparative analysis of ontogenetic variation of expression profiles of plasmatic proteins with potential anti-venom activities of the venomous snake B. jararaca. Furthermore, the present data contributes to the understanding of the natural resistance described in these snakes.
ABSTRACT
Stem cells are characterized by the ability to renew themselves through mitotic cell division and differentiating into a diverse range of specialized celltypes. An important source of adult stem cells is the dental pulp. In dentistry, regenerative strategies are ofimportance because of hard dental tissue damage especially as result of caries lesions, trauma, or iatrogenicprocedures. The regeneration of dental tissues relies on the ability of stem cells to produce extracellular (ECM) proteins encountered in the dental pulp tissue.Thus, the aim of this study was to analyze the expression and distribution of proteins encountered in dental pulpECM (type I collagen, fibronectin, and tenascin) in stem cells. Human immature dental pulp stem cells (hIDPSCs) from deciduous (DL-1 and DL-4 cell lines) and permanent (DL-2) teeth were used. The distribution of ECM proteins was observed using theimmunofluorescence technique. The gene expression profile was evaluated using reverse transcription polymerase chain reaction (RT-PCR) analysis. Positive reactions for all ECM proteins were observed independently of the hIDPSCs analyzed. Type I collagenappeared less evident in DL-2 than in other hIDPSCs. Fibronectin and tenascin were less clear in DL-4. TheRT-PCR reactions showed that type I collagen was lesser expressed in the DL-2 cells, whereas fibronectin and tenascinwere similarly expressed in all hIDPSCs. The distribution and expression of ECM proteins differ among the hIDPSCs. These differences seemed to be related to the donor tooth conditions (deciduous or permanent, retained or erupted, and degree of root reabsorption).
Subject(s)
Male , Female , Humans , Adult , Adult Stem Cells , Extracellular Matrix , Dental Pulp , Collagen Type I , Fibronectins , TenascinABSTRACT
INTRODUCTION: Stem cells are characterized by the ability to renew themselves through mitotic cell division and differentiating into a diverse range of specialized cell types. An important source of adult stem cells is the dental pulp. In dentistry, regenerative strategies are of importance because of hard dental tissue damage especially as result of caries lesions, trauma, or iatrogenic procedures. The regeneration of dental tissues relies on the ability of stem cells to produce extracellular (ECM) proteins encountered in the dental pulp tissue. Thus, the aim of this study was to analyze the expression and distribution of proteins encountered in dental pulp ECM (type I collagen, fibronectin, and tenascin) in stem cells. METHODS: Human immature dental pulp stem cells (hIDPSCs) from deciduous (DL-1 and DL-4 cell lines) and permanent (DL-2) teeth were used. The distribution of ECM proteins was observed using the immunofluorescence technique. The gene expression profile was evaluated using reverse transcription polymerase chain reaction (RT-PCR) analysis. RESULTS: Positive reactions for all ECM proteins were observed independently of the hIDPSCs analyzed. Type I collagen appeared less evident in DL-2 than in other hIDPSCs. Fibronectin and tenascin were less clear in DL-4. The RT-PCR reactions showed that type I collagen was lesser expressed in the DL-2 cells, whereas fibronectin and tenascin were similarly expressed in all hIDPSCs. CONCLUSIONS: The distribution and expression of ECM proteins differ among the hIDPSCs. These differences seemed to be related to the donor tooth conditions (deciduous or permanent, retained or erupted, and degree of root reabsorption).
