Effects of venoms on neutrophil respiratory burst: a major inflammatory function

Abstract

Neutrophils play a pivotal role in innate immunity and in the inflammatory response. Neutrophils are very motile cells that are rapidly recruited to the inflammatory site as the body first line of defense. Their bactericidal activity is due to the release into the phagocytic vacuole, called phagosome, of several toxic molecules directed against microbes. Neutrophil stimulation induces release of this arsenal into the phagosome and induces the assembly at the membrane of subunits of the NAPDH oxidase, the enzyme responsible for the production of superoxide anion that gives rise to other reactive oxygen species (ROS), a process called respiratory burst. Altogether, they are responsible for the bactericidal activity of the neutrophils. Excessive activation of neutrophils can lead to extensive release of these toxic agents, inducing tissue injury and the inflammatory reaction. Envenomation, caused by different animal species (bees, wasps, scorpions, snakes etc.), is well known to induce a local and acute inflammatory reaction, characterized by recruitment and activation of leukocytes and the release of several inflammatory mediators, including prostaglandins and cytokines. Venoms contain several molecules such as enzymes (phospholipase A2, L-amino acid oxidase and proteases, among others) and peptides (disintegrins, mastoporan, parabutoporin etc.). These molecules are able to stimulate or inhibit ROS production by neutrophils. The present review article gives a general overview of the main neutrophil functions focusing on ROS production and summarizes how venoms and venom molecules can affect this function.

Parasite and Pesticide Impacts on the Bumblebee (Bombus terrestris) Haemolymph Proteome

“…Interestingly, the pathway “Neutrophil degranulation_ R-DME-6798695” ( Figure S5 ), which belongs to the innate immune system, was common to Amistar and glyphosate responses. It is involved in immune responses to bacterial infection [ 71 , 72 , 73 ]. In our study, the impact on protein abundance ( Figure S5 , Table S4 ) depended on the substance.…”

The antioxidant activity of lemongrass leaves extract against fibroblasts oxidative stress

“…Neutrophils and macrophages will also experience a respiratory burst, which is an increase in oxygen use and will produce an excessive amounts of Reactive Oxygen Species (ROS), like superoxide and hydrogen peroxide. These species have a beneficial role in microbial killing and also intracellular signalling such as inducing vascular endothelial growth factor (VEGF) in order to enhance the angiogenesis process [3]. At a balanced amounts, ROS has beneficial effects on several physiological processes of the body including wound healing, regulating oxidationreduction reactions, and invading the pathogens [4].…”