Virgin coconut oil abrogates depression-associated cognitive deficits by modulating hippocampal antioxidant balance, GABAergic and glutamatergic receptors in mice

Abstract

Objectives GABA and glutamate neurotransmission play critical roles in both the neurobiology of depression and cognition; and Virgin coconut oil (VCO) is reported to support brain health. The present study investigated the effect of VCO on depression-associated cognitive deficits in mice. Methods Thirty male mice divided into five groups were either exposed to chronic unpredicted mild stress (CUMS) protocol for 28 days or pre-treated with 3 mL/kg b. wt. of VCO for 21 days or post-treated with 3 mL/kg b. wt. of VCO for 21 days following 28 days of CUMS exposure. Mice were subjected to behavioural assessments for depressive-like behaviours and short-term memory, and thereafter euthanised. Hippocampal tissue was dissected from the harvested whole brain for biochemical and immunohistochemical evaluations. Results Our results showed that CUMS exposure produced depressive-like behaviours, cognitive deficits and altered hippocampal redox balance. However, treatment with VCO abrogated depression-associated cognitive impairment, and enhanced hippocampal antioxidant concentration. Furthermore, immunohistochemical evaluation revealed significant improvement in GABAA and mGluR1a immunoreactivity following treatment with VCO in the depressed mice. Conclusions Therefore, findings from this study support the dietary application of VCO to enhance neural resilience in patients with depression and related disorders.

Tramadol rescues visual cortex gliosis and modulates ocular lipido-inflammatory responses in a rat model of paradoxical sleep deprivation

“…These generated free radicals and ROS undergo oxidative reactions with lipids such as the long chain polyunsaturated fatty acids of the eye and play a role in the pathogenesis of most ocular diseases (Nagakannan et al 2012; Njie-Mbye et al 2013). Sleep deprivation is globally known to induce oxidative stress (Li et al 2018a), as well as a driver of lipid peroxidation evident in unusually elevated levels of the oxidant metabolite, MDA (Edem et al 2021). In this study, ocular lipid peroxidation with increased ocular MDA levels following SD was observed, however it was ameliorated following tramadol intervention ameliorated sleep deprivation-induced sleep lipid peroxidation.…”

Tiger nut/coconut dietary intervention as antidotal nutritional remediation strategy against neurobehavioural deficits following organophosphate-induced gut-brain axis dysregulation in mice

“…The NOR test, a test for determining changes in non-spatial working memory, was performed as previously reported [35] . The animals had a first trial (T1) experience in which they were kept in a white, opaque test room with two identical items for three minutes, after which an inter-trial time (IT) of thirty minutes was noted.…”

“…To calculate the percentage of correct modifications, the frequencies of the correct alterations (ABC, ACB, BCA, BAC, CBA, or CAB) between the arms were noted. Edem et al, ($year$) [35] , and calculated using the formula below. The calculation for the percentage alternation is provided below: …”

“…A blind observer recorded the total time of immobility throughout a 6-minute test session. When a mouse stopped struggling and floated passively in the water, only making movements required to maintain its head above the water, it was deemed to be immobile [35] .…”

“…Each mouse was taped to a suspension bar on a plastic suspension box (55 H x 60 W x 11.5 cm D) so that it could not escape or grab onto neighbouring surfaces in order to evaluate depressive-like behaviour using the TST paradigm [35] . During a 6-minute test session, the total number of consistent movements was recorded as real mobility.…”