Improved RNA extraction method using the BioMasher and BioMasher power-plus.

The BioMasher is a disposable homogenizer that was developed to homogenize bovine brain tissue for bovine spongiform encephalopathy diagnosis. Capable of preventing the biohazard risk from infectious samples, it also prevents cross-contamination among samples. The BioMasher is thus widely used in biochemical research, especially for RNA extraction. Here, we tested a novel BioMasher application for RNA extraction from animal and plant tissues. We also developed a grinding machine specific for the BioMasher, named the BioMasher Power-Plus. We developed RNA extraction protocols using the BioMasher combined with the BioMasher Power-Plus. We compared RNA extraction efficiency of the BioMasher with that of the FastPrep and the glass homogenizer. Though the RNA extraction efficiency by the BioMasher was nearly equivalent to that of the FastPrep and the glass homogenizer, sample preparation time was shorter for the BioMasher. The utility of RNA extraction by the BioMasher was examined in mouse, rat, and tomato tissue samples. In the rodent tissues, the highest extraction efficiency of total RNA was from liver, with lowest efficiency from fibrous tissues such as muscle. The quality of extracted total RNA was confirmed by agarose gel electrophoresis which produced highly visible clear bands of 18S and 28S rRNAs. Reproducibility among different operators in RNA extraction from tomato roots was improved by using the BioMasher Power-Plus. The BioMasher and BioMasher Power-Plus provide an effective and easy homogenization method for total RNA extraction from some rodent and plant tissues.

Collagen of chronically inflamed skin is over-modified and upregulates secretion of matrix metalloproteinase 2 and matrix-degrading enzymes by endothelial cells and fibroblasts.

In order to investigate the properties of collagen in chronically inflamed tissue, we isolated collagen from the ear skin of mice with chronic contact dermatitis and examined its biochemical characteristics and the functions that regulate the secretion of matrix metalloproteinase 2 and collagen-degrading enzymes from endothelial cells and fibroblasts. Collagen in skin with chronic contact dermatitis comprised 60% type I collagen and 40% type III collagen, which latter is higher than the content of type III collagen in control skin (35%). The denaturation temperature was higher (42 degrees C) than that of control skin (39 degrees C). The alpha2 chain of type I collagen was over-hydroxylated at both proline and lysine residues. Segment-long-spacing crystallites of type I collagen were unusually connected in tandem. Collagen of chronically inflamed skin was less susceptible to matrix metalloproteinase 2 after heat denaturation. Endothelial cells and fibroblasts secreted an increased amount of matrix metalloproteinase 2 when cultured on a gel formed from the collagen of chronically inflamed skin. Collagen-degrading activity secreted from fibroblasts was also upregulated when cells were in contact with collagen of chronically inflamed skin. These results suggest that the collagen in chronically inflamed tissue has altered biochemical characteristics and functions, which may affect the pathogenesis of the chronic skin disease.

Real-time zymography and reverse zymography: a method for detecting activities of matrix metalloproteinases and their inhibitors using FITC-labeled collagen and casein as substrates.

Zymography and reverse zymography are widely used techniques for identifying the proteolytic activity of enzymes and the presence of protease inhibitors in polyacrylamide gels. In the current studies, we utilized a fluorescein-isothiocyanate-labeled substrate to develop novel zymographic and reverse zymographic methods for detecting matrix metalloproteinases and tissue inhibitors of the metalloproteinases, respectively. Using a transilluminator, the results can be observed visually without stopping the enzymatic reaction. For this reason, we have named these methods real-time zymography and real-time reverse zymography. These methods have the following advantages compared with conventional protocols: (1) because the reaction can be repeatedly monitored on the polyacrylamide gels, optimization of the incubation time can be achieved without preliminary analyses; (2) higher sensitivity is achieved with a lower amount of substrate than with conventional methods; (3) a semi-quantitative analysis of matrix metalloproteinases is possible. An additional advantage of the real-time reverse zymography is that, because the fluorescence detection is specific for substrate digestion, the inhibitor bands can be easily distinguished from contaminating proteins.