Cytotoxicity and the bioconversion strategy of Aristolochia spp

Aristolochia plants are notable from an ethnopharmacological viewpoint, but the relevance of these species for medicinal purposes has been debated because of their inherent toxicity. The convergence of these contrasting realities can be readily achieved using bioconversion methods, which have been shown to be useful tools for numerous applications, including the detoxification of biomass. In this context, methanolic extracts of leaves from Aristolochia triangularis and Aristolochia gibertii, as well as the feces of Battus polydamas larvae fed with leaves from these plants, were prepared, and their cytotoxic activities were evaluated on a human fibroblast cell line (GM07492). The leaf extracts were found to be cytotoxic, leading to reductions of 42.1 and 33.8% on cell viability, respectively, while the fecal extracts were considered inactive. In addition to evidencing the cytotoxicity of A. triangularis and A. gibertii, these findings demonstrated a potential bioconversion strategy for obtaining aristolochiaceous extracts with reduced toxicity using the larvae of a specialist phytophagous insect, thus renewing expectations in relation to the pharmacological importance of Aristolochia spp. The results were also ecologically relevant, as B. polydamas larvae were found to be able to detoxify compounds from host plants.(AU)

Bioactive Fibrin Scaffolds for Use in Musculoskeletal Regenerative Medicine

Abstract Autologous fibrin matrices derived from the Leukocyte and Platelet Rich Plasma (L-PRP) and Leukocyte and Platelet Rich Fibrin (L-PRF) techniques present great potential to act as a bioactive scaffold in regenerative medicine, contributing to the maintenance of cell viability, proliferation stimulus and differentiation. In contrast, there are few studies that characterize the bioactive potential of these fibrin scaffolds by considering the process of production. The objective of this work was to characterize the intrinsic potential of maintaining cell viability of different fibrin scaffolds containing platelets and leukocytes. In order to achieve that, blood samples from a volunteer were collected and processed to obtain fibrin clots using the suggested techniques. To characterize the potential for in vitro viability, mesenchymal stem cells from human infrapatellar fat were used. The scaffolds were cellularized (1x105 cells/scaffolds) and maintained for 5 and 10 days under culture conditions with Dulbecco's Modified Eagle Medium, without addition of fetal bovine serum, and subsequently subjected to analyses by Fourrier transform infra-red spectroscopy, circular dichroism and fluorescence microscopy. The results demonstrated distinct intrinsic potential viability between the scaffolds, and L-PRP was responsible for promoting higher levels of viability in both periods of analysis. No viable cells were identified in the fibrin matrix used as controls. These results allow us to conclude that both fibrin substrates have presented intrinsic potential for maintaining cell viability, with superior potential exhibited by L-PRP scaffold, and represent promising alternatives for use as bioactive supports in musculoskeletal regenerative medicine.

Anatomical correlation between the venter of the soleus muscle and rat leg lenght

An equipment was previously developed in our laboratory to produce a non-invasive contusion in the soleus muscle of the rat. In order to produce the trauma it is also necessary to non-invasively identify the calfof the soleus muscle. The aim of the present study was to identify the calf of the soleus muscle using a correlation between the lenght of the rat leg and the middle region of the muscle. Nine rats were anaesthetised and the lenghts of the animals'legs were then measured with a pachymeter. As an anatomical reference we used the plantar surface of the calcaneus, immediately cranial to its tuberosity, and the cranial face of the distal third of the femoral diaphysis, next to the femoral patellar face, with the articulation of the knee and ankle maintained at 90(degree) of flexion. After dissection and exposure of the soleus muscle, the region where the diameter of the muscular venter was maximal was identified and the distance from this point to the plantar surface of the calcaneus was then measured. Considering this correlation, it was observed that the venter of the rat Soleus muscle is located at a distance from the plantar surface of the calcaneus equal to 44ñ1(per cent) of the rat leg length. This percentage correlation was identified in rats with different body weights and occurred in all of the animals. Subsequent tests, for the induction of a non-invasive trauma, using this correlation, confirmed the efficacy of this methodology for locating the belly of the soleus in a non-invasive way. Three days after trauma, acute signs of injury such as myonecrosis, celular infiltration and muscle fiber basophilia were observed in the ventral face of the soleus muscle.