Vitamin D, Depressive Symptoms, and Covid-19 Pandemic

Abstract

Graphical AbstractRole of vitamin D in the development of depressive symptoms. The synthesis of vitamin D from sunlight is impaired by lockdown and social distance measures imposed by the governments around the world during COVID-10 pandemic. Endogenous vitamin D synthesis initiates in the skin when 7-dehydrocholesterol (7-DHC) is converted in pre-vitamin D3 and then vitamin D3 [25(OH)D3]. It is transported through blood circulation by the vitamin D binding protein (VDBP) to the liver, the kidney, and the brain, where can be converted in its the active form [1,25(OH)2D3]. In the brain, the biological effects of 1,25(OH)2D3 are largely mediated by vitamin D receptor (VDR) through genomic mechanisms, which influence several aspects of serotonin metabolism, such as increasing serotonin synthesis by induction of the tryptophan hydroxylase 2 (TPH2) gene expression; influencing the expression of serotonin reuptake transporter (SERT) and the levels of monoamine oxidase-A (MAO-A), responsible to serotonin catabolism; and indirectly may regulate the synthesis of melatonin that improve the circadian rhythm. This mechanism can be impaired during social isolation and consequent reduction of vitamin D due to low sun exposure during the pandemic, which could contribute to the development of depressive symptoms.

COVID-19 and neurological sequelae: Vitamin D as a possible neuroprotective and/or neuroreparative agent

“…By modulating serotonin and dopamine metabolism, vitamin D has been shown to improve serotoninergic and dopaminergic neurotransmission in cellular models [103] and in an animal model of depression [98] . Activation of the vitamin D receptor by the active form of vitamin D, 1,25(OH)2D3, induces both tryptophan hydroxylase 2 and serotonin reuptake transporter expression as well as monoamine oxidase-A levels [104] . In addition, vitamin D may also modulate some chronobiological processes, possibly preventing the development of depressive symptoms when light-dark cycles are misaligned [68] , [104] .…”

“…Activation of the vitamin D receptor by the active form of vitamin D, 1,25(OH)2D3, induces both tryptophan hydroxylase 2 and serotonin reuptake transporter expression as well as monoamine oxidase-A levels [104] . In addition, vitamin D may also modulate some chronobiological processes, possibly preventing the development of depressive symptoms when light-dark cycles are misaligned [68] , [104] . In this context, we know that one of the most common outcomes of social isolation due to SARS-CoV-2 is the development of stress, anxiety and depression, which have a direct impact on metabolic and psychological equilibrium [105] .…”

Interplay of Nutrition and Psychoneuroendocrineimmune Modulation: Relevance for COVID-19 in BRICS Nations

“…Moreover, the restriction measures at the social and occupational level along with uncertainty about health, perceived fear, and associated factors act as additional factors contributing to deficiencies of these psycho-immune active vitamins. The most notable vitamin in the linkage of COVID-19 and depressive disorders is vitamin D (Shakoor et al, 2020;Ceolin et al, 2021). Vitamin D plays a critical role in the maintenance of the chronobiological rhythms through Vitamin D binding protein and VDR (Jones et al, 2017;Ceolin et al, 2021).…”

“…The most notable vitamin in the linkage of COVID-19 and depressive disorders is vitamin D (Shakoor et al, 2020;Ceolin et al, 2021). Vitamin D plays a critical role in the maintenance of the chronobiological rhythms through Vitamin D binding protein and VDR (Jones et al, 2017;Ceolin et al, 2021). Vitamin D also acts as an antidepressant; upholds serotonergic neurotransmission through induction of tryptophan hydroxylase 2 gene expression (Ceolin et al, 2021).…”

Vitamin D3 and its necessity for health

“…Depressive illness is proportional to serum vitamin D concentration because of its surging impact on serotonergic neurotransmitter [ 23 ]. Calcitriol in parental form piles up VDR and brain-derived neurotrophic factor (BDNF) in hippocampus of brain, which clearly proves healing of depression and motor malfunction [ 24 ].…”