Improving Mitochondrial Function Protects Bumblebees from Neonicotinoid Pesticides

Abstract

Global pollination is threatened by declining insect pollinator populations that may be linked to neonicotinoid pesticide use. Neonicotinoids over stimulate neurons and depolarize their mitochondria, producing immobility and death. However, mitochondrial function can be improved by near infrared light absorbed by cytochrome c oxidase in mitochondrial respiration. In flies, daily exposure to 670nm light throughout life increases average lifespan and aged mobility, and reduces systemic inflammation. Here we treat bumble bees with Imidacloprid a common neonicotinoid. This undermined ATP and rapidly induced immobility and reduced visual function and survival. Bees exposed to insecticide and daily to 670nm light showed corrected ATP levels and significantly improved mobility allowing them to feed. Physiological recordings from eyes revealed that light exposure corrected deficits induced by the pesticide. Overall, death rates in bees exposed to insecticide but also given 670nm light were indistinguishable from controls. When Imidacloprid and light exposure were withdrawn, survival was maintained. Bees and insects generally cannot see deep red light so it does not disturb their behaviour. Hence, we show that deep red light exposure that improves mitochondrial function, reverses the sensory and motor deficits induced by Imidacloprid. These results may have important implications as light delivery is economic and can be placed in hives/colonies.

Non‐mammalian Hosts and Photobiomodulation: Do All Life‐forms Respond to Light?

“…Powner et al . in London reasoned that using PBM to stimulate the bees’ mitochondria might overcome the inhibition caused by neonicotinoids. The experiment comprised four groups with a 10‐day treatment period and a 22‐day recovery period: (1) controls, (2) neonicotinoid alone, (3) PBM alone and (4) PBM + neonicotinoid.…”

Aging retinal function is improved by near infrared light (670 nm) that is associated with corrected mitochondrial decline

“…Specific long wavelengths of light are absorbed by cytochrome c oxidase in mitochondria (Fitzgerald et al., 2013), and this is associated with improved respiration, increased membrane potentials and improved ATP production (Gkotsi et al., 2014, Kokkinopoulos et al., 2013), and reductions in key markers of age-related retinal inflammation (Begum et al., 2013). In Drosophila, long wavelength light also increases mean lifespan and mobility (Begum et al., 2015), and in bumble bees, it has similar impact but also improves the electroretinogram in normal animals and those in which mitochondrial function has been undermined by insectiside exposure (Powner et al., 2016). Here, we ask if 670 nm light exposure that is associated with corrected mitochondrial function and reduced inflammation translates to improved retinal function in aged mice.…”

Red light corrects neonicotinoid induced immunodeficiency and impaired respiration in poisoned bumblebees

“…2016). The consequence is bumblebees have reduced ATP production, impaired visual function and restricted mobility resulting in reduced ability to feed leading to death (Lambin et al, 2001;Nauen et al, 2001;Suchail et al, 2001;Medrzycki et al, 2003;Colin et al, 2004;Powner et al, 2016). Neonicotinoids also suppress bee immunity rendering them vulnerable to pathogens (Brandt et al, 2016;Di Prisco et al, 2013), Mitochondria are key players in ageing, disease and immunity.…”

“…In diverse species this improves their membrane potential, increases the efficiency of the electron transport chain and corrects compromised ATP production (Begum et al, 2013;Kokkinopoulous et al, 2013;Gkotsi et al, 2014). In insects it also improves retinal function, mobility, cognitive function including memory and extends average lifespan (Powner et al, 2016;Weinrich et al, 2017;Begum et al, 2015). Hence, in both bumblebees and flies daily exposure to 670nm light reduces death rates.…”

“…4 670nm protects bumblebees from Imidacloprid, a major neonicotinoid pesticide, when given for 15 mins twice daily. This corrects damaged retinal function, mobility and survival (Powner et al, 2016), but if this is to be used effectively, a greater understanding of the overall impact of 670nm light is needed in terms of its influence over immune-competence. Further, there is a need to understand the required metrics of exposure and their influence over time in bumblebees damaged by pesticide.…”