Vitamin B6 plays a role in the regulation of anserine, carnosine, histamine, and GABA, and it may also influence the P2X7R-NLRP3 inflammasome, which could contribute to the reduction of oxidative stress, and the reduction of oxidative stress. 9
Research shows that pyridoxine enhances antioxidant responses, likely through the upregulation of nuclear Nrf2 gene expression, while also lowering mitochondrial reactive oxygen species( ROS) levels. Supplementation with PLP led to reduced activation of the NLRP3 inflammasome and a decrease in the production of inflammatory cytokines in macrophages, linking mitochondrialderived ROS production to nuclear signalling pathways within immune cells. 14 The involvement of vitamin B6 in the metabolism of sugars and lipids may contribute to the reduction of advanced glycation end products and lipoxygenation end products. 8
Vitamin B6 and the Immune System Pyridoxine deficiency leads to impairment of immune responses. 23 Vitamin B6 plays various roles in the immune system, 13 such as participating in the functioning of the entire immune system, supporting both innate and acquired immunity, 9 and is required for antibody production. 23 Vitamin B6 supplementation has been found to increase total lymphocytes in patients with chronic disease. 9 Vitamin B6 plays a key role in the production of T lymphocytes and interleukins. 9 Vitamin B6 supports a Th1 cytokine-mediated immune response and modulates immune cell function. 34 Vitamin B6 deficiency disrupts the Th1-Th2 balance toward an excessive Th2 response, which may result in allergies. 9 PLP plays a significant role in shaping the intestinal microbiota, which in turn has an impact on immune responses. 9
A deficiency of vitamin B6 results in a weakened immune response, 9 characterised by atrophy of lymphoid organs, 35 a decrease in lymphocyte numbers, 35 a reduction in serum antibody levels, 9 a decline in IL-2 production, 9, 35 and an elevation in IL-4 levels. 9
Deficiency of Vitamin B6
A deficiency of B vitamins may arise from various factors, such as dietary insufficiency, 22 intestinal absorption, 36 malabsorption syndromes( such as Crohn’ s disease, ulcerative colitis and coeliac disease), 5, 16 16, 22
inflammation, decreased protein binding capacity of plasma, 21 variation in enzyme binding affinity, 29 altered or defective cellular and intercellular transport, 36
22, 36 impaired or altered metabolism, high and continuous alcohol consumption, 5, 13, 16 smoking, 13 oral contraceptive use, 16, 37 analgesics, 13 antibacterials, 13 penicillamine, 16 antidiabetic medications, 13 metformin, 38 antidepressant medications, 13 isoniazid, 16 calcium blockers, 13 asthma prescriptions, 13 lipidlowering medications, 13 antiepileptic medications, 5, 13, 25 severe renal disease, 5, 16 pregnancy, 16 and certain genetic disorders such as homocystinuria. 5 Additionally, a deficiency may arise when the physiological requirement for the vitamin is higher than the intake or the intake is suboptimal. 36 Age-related declines in both dietary vitamin B6 intake and plasma PLP concentration have been observed in males and females, 13 with vitamin B6 status declining with age across adulthood, particularly in males. 21 These factors may compromise vitamin B6 levels and status, highlighting the importance of monitoring dietary intake and implementing appropriate nutritional interventions.
Prolonged deficiency of vitamin B6 has been associated with the development of a painful axonal peripheral neuropathy, which results in symptoms such as muscle weakness, diminished reflexes, sensory impairment, and ataxia, especially affecting the lower extremities. 10 Low vitamin B6 status, based on plasma PLP concentrations, has been identified in diseases associated with low-grade inflammation. 10 Various health issues may arise due to the involvement of vitamin B6 as a coenzyme in the synthesis of haemoglobin and neurotransmitters. 10 Health conditions linked with low vitamin B6 status are shown in Table 2.
Microcytic anaemia 4, 5, 10 Microcytic hypochromic anaemia 4
Anaemia 4, 11 5, 10, 11, 30
Depression
Irritability 30 30, 31
Premenstrual syndrome 5, 10, 11
Confusion Cognitive decline 10 or impairment 13 Electroencephalographic abnormalities 5, 11 Convulsive seizures 5 Non-responsive polymorphic seizures 4 Recurrent neonatal or infantile seizures 5 Painful axonal peripheral neuropathy 10 Increased nerve excitability 4 Carpal tunnel syndrome 39
Irritability 11 10, 13, 15
Cardiovascular disease
5, 7, 9, 13, 15, 24
Homocysteinaemia
10, 15-17, 40
Type 2 Diabetes Fatty acid accumulation 4 Lipid profile alteration 4 Decreased carnitine biosynthesis 4
Dermatitis 5, 11
Glossitis 11
Migraine 10 4, 5, 9, 11, 13, 15, 35, 41, 42
Weakened immune system Impaired antibody response 23 Reduced immune response 23
Lymphopaenia 4
Impaired or delayed hypersensitivity response 23 Rheumatoid arthritis 10 Hashimoto’ s thyroiditis 43 Inflammatory bowel disease 10 Altered lung function 32
10, 13, 15, 16, 43
Inflammation Oxidative stress 13 Tissue damage caused by free radicals 9 Lipid peroxidation 32 Hyperemesis gravidarum 4 Frailty in the elderly 13 Impaired mobility 13
13, 24
Reduced physical performance
Table 2. Health conditions linked with low vitamin B6 status
72 | vol31 | no2 | JATMS