Collagenolytic enzymes produced by fungi: a systematic review

Abstract Specific proteases capable of degrading native triple helical or denatured collagen have been required for many years and have a large spectrum of applications. There are few complete reports that fully uncover production, characterization and purification of fungi collagenases. In this review, authors searched through four scientific on line data bases using the following keywords (collagenolytic OR collagenase) AND (fungi OR fungus OR fungal) AND (production OR synthesis OR synthesize) AND (characterization). Scientific criteria were adopted in this review to classify found articles by score (from 0 to 10). After exclusion criteria, 21 articles were selected. None obtained the maximum of 10 points defined by the methodology, which indicates a deficiency in studies dealing simultaneously with production, characterization and purification of collagenase by fungi. Among microorganisms studied the non-pathogenic fungi Penicillium aurantiogriseum and Rhizoctonia solani stood out in volumetric and specific collagenase activity. The only article found that made sequencing of a true collagenase showed 100% homology with several metalloproteinases fungi. A clear gap in literature about collagenase production by fungi was verified, which prevents further development in the area and increases the need for further studies, particularly full characterization of fungal collagenases with high specificity to collagen.

Comparative immunocytochemistry of isolated rat & monkey pancreatic islet cell types.

BACKGROUND & OBJECTIVES: Data on comparative distribution of the islet cell types in the Indian bonnet monkeys and rats are not available. The aim of the present study was to compare the arrangement of the three islet cell types in the native and in isolated rat and Indian bonnet monkey islets by immunocytochemistry. METHODS: Rat islets isolated by chopped tissue collagenase digestion method and islets of monkey isolated by intraductal collagenase digestion method were immunostained by streptavidin-biotin peroxidase method. RESULTS: Immunocytochemical staining of the isolated islets in both the species revealed the presence of three different cell types: insulin secreting B cells, glucagon secreting A cells and somatostatin secreting D cells. The arrangement of islet cell types in the rats and monkeys was similar to that of the intact islets of the native pancreas but were arranged in a definite pattern. In rats the A and D cells were peripherally arranged around the centrally located B cells. In monkeys the B cells occupied the majority of the periphery while the A and D cells were found mostly in the centre. INTERPRETATION & CONCLUSION: The findings of the present study showed that the arrangement of cell types in the islets was not affected by the isolation procedure. The difference in the arrangement of islet cell types in the two species may reflect special functional adaptations.

Comportamento dos hemócitos e da matriz extracelular de Biomphalaria glabrata com diferentes graus de resistência ao Schistosoma mansoni: (Estudo ultraestrutural) / Behavior of hemocytes and extracellular matrix of Biomphalaria glabrata with different degrees of resistance to Schistosoma mansoni (Ultrastructural study)

O sistema interno de defesa dos moluscos é baseado sobretudo no encapsulamento, fagocitose e destruição das formas invasoras pelos hemócitos. Estudos realizados com o auxílio de técnicas de microscopia eletrônica permitiram elucidar as principais características ultraestruturais destas células e das cápsulas ou complexos encapsulantes por elas formados. Entretanto, as modificações que os hemócitos exibem em animais com diferentes gràus de susceptibilidade ao S. mansoni, o comportamento da matriz extracelular nos complexos encapsulantes e a formação de granulomas ainda não foram suficientemente explorados. [MATERIAIS E MÉTODOS]: Exemplares de B. glabrata provenientes de regiões geográficas distintas foram submetidos às análises histológicas (coloração pela hematoxilina/eosina, sírius-vermelho, orceína e Weigert), ultraestruturais e bioquímicas (técnica de hidroxiprolina). [RESULTADOS]: Os achados confirmam que somente um tipo celular (hemócito fagocitico) está presente nas reações celulares. Os elementos da matriz extracelular pesquisados não mostraram participação no interior ou na periferia das reações celulares hemocitárias. [CONCLUSÃO]: As reações teciduais de defesa em B. glabrata contra o S. mansoni são exclusivamente celulares não estando associadas á sintese e deposição de elementos da matriz extracelular.

Collagenase specificity in chondrosarcoma metastasis

The treatment of some mesenchymal malignancies has made significant gains over the past few decades with the development of effective systemic therapies. In contrast, the treatment of chondrosarcoma has been limited to surgical resection, with the most significant prognostic indicators being surgical margins and histologic grade. We have reported that MMP-1/TIMP-1 gene expression serves to prognosticate for tumor recurrence in this group of patients. This led to the hypothesis that collagenase activity facilitates cell egression from the cartilaginous matrix. In the current study we examine the specificity of collagenase gene expression in archival human chondrosarcoma samples using semi-quantitative PCR. Messenger RNA was affinity extracted and subject to reverse transcription. The subsequent cDNA was amplified using novel primers and quantitated by densitometry. Ratios of gene expression were constructed and compared to disease-free survival. The data demonstrate that the significance of the MMP-1/TIMP-1 ratio as a predictor of recurrence is confirmed with a larger number of patients. Neutrophil collagenase or MMP-8 was observed in only 5 of 29 samples. Collagenase-3 or MMP-13 was observed in all samples but the level did not correlate with disease-free survival. Since the collagenases have similar activity for fibrillar collagens and cleave the peptide in the same location, post-transcriptional regulatory mechanisms may account for the observed specificity. The determination of the MMP-1/TIMP-1 gene expression ratio not only serves to identify those patients at risk for recurrence but may also serve as a novel therapeutic avenue as an adjunct to surgical resection

Influence of Aloe vera on collagen turnover in healing of dermal wounds in rats.

Treatment of full-thickness wounds with A. vera, on rats resulted in increased biosynthesis of collagen and its degradation. A corresponding increase in the urinary excretion of hydroxyproline was also observed. Elevated levels of lysyl oxidase also indicated increased crosslinking of newly synthesised collagen. The results suggest that A. vera influences the wound healing process by enhancing collagen turnover in the wound tissue.

The role of collagen in hematopoiesis

Several types of collagen, including types I, III, IV, V and VI, are produced by bone marrow stromal cells. Current information indicates that changes in collagen production result in profound alterations in the capacity of hematopoietic precursors to proliferate and differentiate. Although not definitively established, collagen molecules may be involved in the establishment and conformation of the stroma-associated extracellular matrix and/or in adhesive interactions with progenitor cells. The dynamic role of collagen in hematopoiesis is indicated by the observation that collagen production and processing are regulated by several factors such as glucocorticoids, cytokines, collagenases and collagenase-inhibitory proteins.