Vitamin D and the Immune System. When? Why? How?

Abstract

Vitamin D, called “the sunshine vitamin” is essential for the good functioning of the human body. Vitamin D generates its principal effects via the vitamin D receptor (VDR), a specific zinc-finger nuclear receptor, located primarily in the nuclei of target cells. VDR is present in most tissues and cells in the body such as in the: digestive system, cardiovascular system, immune system. This receptor represents the key to the understanding of vitamin D non-skeletal effects. Recently, some data were published on the correlation between vitamin D levels and sepsis, indicating a prevalence of vitamin D deficiency of approximately 61.6% in sepsis patients and of 74% in patients admitted to intensive care units (ICU). Vitamin D deficiency in critically ill patients is associated with infection and sepsis, and this association is based on the relation between vitamin D and inflammatory cytokine. Vitamin D, via VDR influences the secretion of cytokines and antimicrobial peptides. Practically, vitamin D acts as an immunomodulator stimulating the differentiation of cells of the innate immune system and, regulating T and B cell proliferation. The data clearly show predominant effects of vitamin D on the adaptive immune function. Vitamin D modulates the T cell phenotype specially that of CD4+ helper T cells (Th1, Th2, as well as Th17 sub-grups). The amplitude of the response to vitamin D depends on a cell’s state of activation, as the number of VDR in inactive cells is low, but may increase five times after activation It was found that the intestinal expression of VDR regulates the host’s microbiome and mediates the anti-inflammatory effects of probiotics. A low level of vitamin D in ICU patients is demonstrated and has many causes. The rapid correction of this deficiency by administering very high doses of vitamin D is possible without causing adverse effects like hypercalcemia or hypercalciuria. Vitamin D is more than just a vitamin. It has clear effects on the immune system, in particular in patients with autoimmune diseases and critically ill. Currently, the majority of data strongly support the association, between low vitamin D levels and sepsis rather than a causal relation. Vitamin D is emerging as a promising and relatively safe nutrient for developing new preventive strategies and adjuvant treatments of diseases, caused by impaired immune-homeostasis. In addition, its supplmentation is very easy and safe.

Impact of General Anesthesia Guided by State Entropy (SE) and Response Entropy (RE) on Perioperative Stability in Elective Laparoscopic Cholecystectomy Patients—A Prospective Observational Randomized Monocentric Study

“…A high percentage of these patients have decreased cardiac output with hemodynamic collapse due to increased intra-abdominal pressure, which leads to the compression of the inferior vena cava and further decrease of venous return. Furthermore, the increased vascular resistance leads to an increased motor load of the heart with tachycardia which can lead to hemodynamic collapse [ 16 , 17 , 18 , 19 , 20 ]. It is well-known that one of the pharmacodynamic effects of volatile anesthetics is their impact on the heart function [ 21 , 22 , 23 ], but it should be noted that, apart from its effects on the hemodynamic status, Sevoflurane also has cardioprotective properties.…”

Multiparametric Monitoring of Hypnosis and Nociception-Antinociception Balance during General Anesthesia—A New Era in Patient Safety Standards and Healthcare Management

“…When P a O 2 exceeds 100 mmHg, the patient is characterized by hyperoxia, the most important systemic effect being the increased and accelerated production of reactive oxygen species (ROS) and the development of oxidative stress (OS) [ 93 , 94 , 95 , 96 , 97 , 98 , 99 ]. The most important mechanisms through which OS is augmented in the case of general anesthesia are represented by the increase in molecular oxygen offerings at the mitochondria, the interaction with reactive nitrogen species (RNS), and lipid peroxidation with destruction of cellular membranes [ 25 , 100 , 101 , 102 , 103 ] ( Figure 2 ).…”

Multiparametric Monitoring of Hypnosis and Nociception-Antinociception Balance During General Anesthesia - A New Era in Patient Safety Standards and Healthcare Management

“…When PaO2 exceeds 100 mmHg the patient is characterized by hyperoxia, the most important systemic effect being the increased and accelerated production of reactive oxygen species (ROS) and the development of oxidative stress (OS) [93][94][95][96][97][98][99]. The most important mechanisms through which OS is augmented in the case of general anesthesia are represented by the increase in molecular oxygen offerings at the mitochondria, the interaction with reactive nitrogen species (RNS), and lipid peroxidation with destruction of cellular membranes [25,[100][101][102][103]. (Figure 2) Nunes et al have studied the implications of general anesthesia (GA) on the redox profile of surgical patients that underwent intravenous GA, as well as the implications of multimodal monitoring based on Entropy on the oxidoreduction activity.…”