Action of neuwiedase, a metalloproteinase isolated from Bothrops neuwiedi venom, on skeletal muscle: an ultrastructural and immunocytochemistry study

• Published in: Journal of Venomous Animals and Toxins including Tropical Diseases
• Main Authors: C Baldo, MJ Ferreira, DS Lopes, LFM Izidoro, AO Gomes, EAV Ferro, A Hamaguchi, MI Homsi-Brandeburgo, VM Rodrigues
• Format: Article in Journal/Newspaper
• Language: English
• Published: SciELO 2010
• Subjects: skeletal muscle; neuwiedase; snake venom metalloproteinases; Bothrops neuwiedi; Arctic medicine. Tropical medicine; RC955-962; Toxicology. Poisons; RA1190-1270; Zoology; QL1-991; Arctic
• Online Access: https://doi.org/10.1590/S1678-91992010000300013; https://doaj.org/article/70f08337aac74713a044f26b3e38e393

The damaging effects of neuwiedase, a non-hemorrhagic snake venom metalloproteinase from P-I class, on gastrocnemius muscle are studied herein. Following neuwiedase injection, ultrastructural alterations were detected early showing disarrangement of skeletal muscle fibers (characterized by discontinuity of Z lines), mitochondrial swelling, and disruption of plasma membrane and basal lamina. Degradation of skeletal muscle and the appearance of an amorphous substance, primarily composed of cellular debris, were noted after 24 hours. The presence of neuwiedase at the injection site (detected by immunocytochemistry) revealed highly specific labeling of myofibril components of damaged myocytes. In addition, proteolysis of muscle proteins assayed through myofibrils extracted from gastrocnemius muscle indicated that neuwiedase provoked degradation of myofibrils, especially myosin. These results suggest that skeletal muscle damage, induced by neuwiedase, is probably due to its proteolytic action on myofibrils, which are responsible for the maintenance of the cellular architecture.