Neuroprotective Effect of Cannabidiol Against Hydrogen Peroxide in Hippocampal Neuron Culture

Abstract

Introduction: Reports on the neurotoxic and neuroprotective effects of cannabidiol (CBD) have not been in complete accord, showing different and somewhat contradictory results depending upon the brain cell types and experimental conditions employed. This work systematically examines the neuroprotective capability of CBD against oxidative stress (i.e., hydrogen peroxide [H 2 O 2 ]) as well as its toxicity profile in the in vitro culture platform of primary hippocampal neurons. Materials and Methods: The low cell-density (100 neurons per mm 2) culture was used for analyzing the viability and morphology of neurons at a single-cell level with a confocal laser-scanning microscope (CLSM). Primary neurons were obtained from the hippocampal tissues of embryonic day-18 (E18) Sprague-Dawley rat pups and treated with CBD (0.1-100 lM) and/or H 2 O 2 (0.1-50 lM) at 1 DIV (days in vitro). Results: The lethal concentration 50 (LC 50) value (the concentration causing 50% cell death) of CBD was calculated to be 9.85 lM after 24 h of incubation, and that of H 2 O 2 was 2.46 lM under the same conditions. The neuroprotection ratio of CBD against H 2 O 2 ([H 2 O 2 ] = 10 lM) was 2.40 with 5 lM of CBD, increasing the cell viability to 57% from 24%. The CLSM analysis suggested that the cell-death mechanisms were different for CBD and H 2 O 2 , and CBD did not completely rescue the morphological alterations of primary hippocampal neurons caused by H 2 O 2 , such as neurite degeneration, at least in the in vitro neuron culture. Conclusion: Although CBD showed both neurotoxic and neuroprotective effects on hippocampal neurons in the in vitro setting, the use of low-concentrated (i.e., 5 lM) CBD, not causing toxic effects on the neurons, significantly rescued the neurons from the oxidative stress (H 2 O 2), confirming its neuroprotection capability.

Protective effects of cannabidiol on the membrane proteins of skin keratinocytes exposed to hydrogen peroxide via participation in the proteostasis network

“…This is all the more important as CBD, which has lipophilic character, tends to accumulate in cell membranes, especially when the cells are exposed to UV radiation, including in the sunlight as well as to hydrogen peroxide [ 8 , 11 ]. Our previous research as well as data from the literature clearly show that CBD can protect various cells, including skin cells, by preventing damage from oxidative stress resulting from exposure to H 2 O 2 [ 8 , [12] , [13] , [14] ]. The antioxidant activity of CBD results mainly from the reduction of the excessive generation of oxidants, which promotes, among other, the inhibition of ROS-dependent lipid peroxidation [ 8 , 11 , 15 ].…”

Regulatory Effects of Cannabidiol on Mitochondrial Functions: A Review

“…The effects of CBD on oxidative stress and ROS production in neuronal cells are well documented [ 41 , 49 , 50 , 79 , 80 ]. Treatment with 5 µM CBD has been shown to attenuate the OGD/R-induced damage of HT22 hippocampal cells, in part, due to the reduction in oxidative stress [ 41 ].…”

“…Mechanistically, CBD was found to exert protective effects by attenuating the OGD/R-induced decrease in glutathione content and glutathione peroxidase activity [ 41 ]. The neuroprotective effects of CBD have also been studied in a model of primary hippocampal neuronal cells from embryonic Sprague Dawley rats [ 49 ]. Co-treatment with 5 µM CBD increased the viability of primary hippocampal neurons treated with 10 µM hydrogen peroxide from 24% to 57% [ 49 ].…”

“…The neuroprotective effects of CBD have also been studied in a model of primary hippocampal neuronal cells from embryonic Sprague Dawley rats [ 49 ]. Co-treatment with 5 µM CBD increased the viability of primary hippocampal neurons treated with 10 µM hydrogen peroxide from 24% to 57% [ 49 ]. Despite the observed therapeutic effects, the concentration of CBD treatment alone causing 50% cell death in hippocampal neurons was calculated at 9.85 µM, suggesting that CBD may have a biphasic effect on hippocampal cells, exhibiting neuroprotective effects at lower doses but also causing neurotoxicity at suprapharmacological concentrations [ 49 ].…”

The Effect of Cannabidiol on UV-Induced Changes in Intracellular Signaling of 3D-Cultured Skin Keratinocytes

“…Moreover, in UV irradiated keratinocytes, CBD prevents dysfunction in the antioxidant system associated with glutathione peroxidase and thioredoxin reductase activity and activates the cytoprotective Nrf2/ARE pathway [9,10]. The antioxidant effect of CBD prevents changes in the structure and function of the cell membrane and supports cell viability under oxidative conditions [8,11,12]. Moreover, CBD by interacting with membrane cannabinoid receptor CB2 reduces inflammation significantly by decreasing TNFα level [7].…”