The association between vitamin D levels and oxidative stress markers in Egyptian Behcet’s disease patients
Orphanet Journal of Rare Diseases volume 17, Article number: 264 (2022)
Oxidative stress is postulated to have a major role in the pathophysiology of Bechet’s Disease (BD). Growing evidence suggests that vitamin D has important roles in enhancing the expression of anti-inflammatory cytokines as well as certain antioxidants. However, there is little evidence currently about the antioxidant properties of vitamin D in BD.
To study the relationship between vitamin D levels and the oxidative stress markers in patients with BD in addition to its association with disease activity and severity.
Sixty BD patients (45 males, 15 females; mean age: 34.2 ± 9.6 years) were enrolled in this study and compared to a sex and age matched control group. Plasma 25-Hydroxy vitamin D (25-OH-D) was measured using Human (25-OH-D) ELISA assay. Plasma malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), superoxide dismutase (SOD) activity, catalase (CAT) activity and total antioxidant capacity (TAC) were determined by spectrophotometric methods in both groups. Plasma calcium (Ca) was measured by ELISA assay.
When compared to controls vitamin D, GSH, CAT activity, TAC and Ca were significantly lower in BD patients, while MDA and NO levels were significantly increased in BD patients. Our Results Found that vitamin D was inversely correlated to BD current Activity form (BDCAF), disease severity score, ESR, CRP, MDA and NO, while vitamin D was significantly positively correlated to GSH, SOD, TAC and Ca.
Our study confirms that a lower level of vitamin D is associated with the oxidative stress state in BD patients as detected by MDA and NO elevation as well as decreased GSH, SOD activity, CAT activity and TAC. Hence, Vitamin D fortified foods and beverages or supplementation may improve disease severity and oxidative stress in BD patients.
Behcet’s disease (BD) is a systemic vasculitis with an unknown pathogenesis. It follows a chronic course with inflammatory attacks. The disease is manifested by recurrent oral and genital ulcers, mucocutaneous lesions, vascular, articular, ocular, neurological, cardiac as well as gastrointestinal involvement. BD is of an unknown etiology .
Tissue infiltration by active polymorphnuclear cells (PMN) has been detected in BD. Furthermore, their main functions are found to be up regulated in BD i.e. secretion of free radicals (FR), chemoattraction, and phagocytosis . The oxidative stress state from enhanced FR secretion may result in an endothelial toxicity and tissue damage in BD .
Vitamin D (Vit D) is a fat-soluble vitamin that is essential for normal immune function. A good deal of evidence implicates Vit D in the pathogenesis of several inflammatory diseases including BD .
Vitamin D has important roles in enhancing the expression of anti-inflammatory cytokines as well as certain antioxidants . It has been found to regulate the ROS concentrations by its anti-inflammatory functions and mitochondrial secretion of antioxidants through cell signaling pathway [6, 7].
Despite that oxidative stress is involved in the pathophysiology of Behcet’s Disease, limited data related to the effect of vitamin D deficiency on oxidative stress in BD is available. Therefore, we aimed at evaluating the relationship between vitamin D levels and the oxidative stress markers in Patients with Behcet’s Disease (BD) and its association with disease activity and severity.
Patients and methods
This case control study was conducted in Kasr Al Ainy Medical Hospital, The Medical Biochemistry department of Kasr Al Ainy and Excellent center of National Research Centre (NRC) in Cairo in the period between October 2020 and November 2021. This study was approved by the Ethical Committee of Kasr Al Ainy Medical Hospital and was in accordance with the principles of Helsinki Declaration, the protocol of the study was approved by the NRC Ethics committee (Registration Number is20136) and all participants provided written informed consent.
Ninety five Egyptian subjects participated in the present study. Sixty patients were diagnosed according to the International Criteria for Behcet’s Disease (ICBD) , they were recruited from the Rheumatology department of Kasr Al Ainy hospitals, Cairo University & from the Medical Centre of Excellence, National Research Centre, Cairo, Egypt ( 45 males / 15 females; mean age 34.26 ± 6.96 years, mean disease duration 9.55 ± 6.60 years and 35 unrelated healthy controls with similar demographic characteristics (26 males / 9 females, mean age 33.51 ± 6.74 years).
The Detailed medical history and full physical examination were collected by expert rheumatologists. For venous and arterial thrombotic events, Doppler ultrasonography, angiography, MRI, CT, and echocardiography were done. Radiologic evaluations, including, CT scans of the lungs and the abdomen, cranial magnetic resonance imaging (MRI) were performed as clinically indicated. Behcet's Disease current Activity form (BDCAF) was used for assessment of disease activity .
The clinical severity score for BD  was calculated as the sum of 1 point each for mild symptoms (oral aphthosis, genital ulcers, arthralgia and typical skin lesions such as, erythema nodosum, papulopustular lesions and folliculitis), 2 points each for moderate symptoms (arthritis, anterior uveitis, gastrointestinal involvement and deep vein thrombosis of the legs) and 3 points each for severe disease manifestations (retinal vasculitis, posterior/panuveitis, arterial thrombosis, neuro-Behçet's and bowel perforation). Patients were categorized according to the disease severity score as follows: severe group ≥ 7 points, moderate group, a score between 4 and 6 points and mild group < 4 points.
Patients Exclusion criteria were: diabetes; neoplasia; cigarette smoking; other autoimmune diseases; pregnancy; chronic renal failure; liver disease; thyroid disorders; parathyroid disorders; fibromyalgia; antioxidants, vitamin D and calcium supplementation within three months prior to the study.
Collecting detailed basal data about nutritional habits and intake through 24 hour recalls was recorded. Analysis of micronutrients amounts in food intake using World Food Dietary Assessment System (WFDAS) 1995, University of California—USA. Recommended Dietary Allowance (RDA) is the average daily dietary intake level of a nutrient considered sufficient by the Food and Nutrition Board of the Institute of Medicine to meet the requirements of nearly all (97%-98%) healthy individuals.
Venous blood samples were obtained from patients and controls. Samples were collected into heparinized vacutainers (Becton Dickinson, USA). Heparinized blood samples were used for separation of plasma for the estimation of 25-Hydroxy vitamin D and oxidative stress markers (MDA, GSH, TAC and antioxidant enzymes “SOD and CAT activities”).
25-Hydroxy vitamin D Measurement
25-Hydroxy vitamin D (25-OH-D) was measured using Human (25-OH-D) ELISA Assay (epitope diagnostics Co., USA) . Vitamin D ‘deficiency’ was defined as vitamin D levels lower than 20 ng/mL. Vitamin D levels higher than 20 ng/mL and lower than 30 ng/mL were ascribed to vitamin D ‘insufficiency’. Vitamin D ‘sufficiency’ was defined as levels higher than 30 ng/mL .
Measurement of oxidant/antioxidant parameters
Lipid peroxidation was quantified in the plasma samples by measuring the levels of a secondary product of lipid peroxidation, malondialdehyde (MDA). MDA thiobarbituric acid adducts formed were measured spectrophotometrically at 534 nm .
Determination of superoxide dismutase (SOD) activity
The method is based on the ability of the enzyme to inhibit the phenazine methosulphate-mediated reduction of nitroblue tetrazolium dye in the plasma. The activity of sample was determined by comparing the increase of absorbance during one minute between sample and blank at 560 nm. Then the percent of inhibition was determined by subtracting the activity of sample from one hundred percent of blank .
Determination of catalase (CAT) activity
Catalase activity was evaluated by a method of Aeb , which is based on decomposition of H2O2 by catalase. Catalase reacts with a known quantity of H2O2, the reaction is stopped after exactly one minute with catalase inhibitor. In the presence of peroxidase (HPR), remaining H2O2 reacts with 3,5-Dichloro-2-hydroxybenzene sulfonic acid (DHBS) and 4-aminophenazone (AAP) to form a chromophore with a color intensity inversely proportional to the amount of catalase in the original sample.
Determination of reduced glutathione (GSH) levels
Reduced glutathione in the blood was determined by the method of Beutler et al. (1963) . GSH was measured by determining the yellow coloured complex formed by the conversion of 5,5′-dithio-bis 2-nitrobenzoic acid (DTNB) to 2-nitro-5-mercaptobenzoic acid in the plasma, which was measured by the spectrophotometer at 405 nm.
Determination of total antioxidants capacity (TAC)
Plasma TAC was determined according to the colorimetric method of Koracevic et al. (2001) . The assay measured the capacity of the biological fluids to inhibit the production of thiobarbituric acid reactive substances (TBARS) from sodium benzoate under the influence of the free oxygen radicals derived from Fenton's reaction. This reaction can be measured spectrophotometrically at 532 nm.
Nitric oxide (NO) Assay
Nitric Oxide Colorimetric Assay Kit provides convenient measure of total nitrate/nitrite in a simple two-step process. The first step converts nitrate to nitrite utilizing nitrate reductase. The second step uses Griess Reagents to convert nitrite to a deep purple azo compound. The amount of the azo chromophore accurately reflects nitric oxide amount in samples. The resulting azo dye has a bright reddish—purple color which can be measured at 540 nm .
Determination of Total calcium (Ca)
Calcium was measured by ELISA kit (Glory Science Co., USA).
Laboratory investigations done for all patients and controls included: Complete blood picture (CBC), Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), serum alkaline phosphatase (ALP), serum Creatinine and serum urea.
The data obtained from the experiments were analyzed using the Statistical Package for the Social Sciences, version 21.0, SPSS Inc, Chicago, Illinois, USA (SPSS). Data were statistically described in terms of mean ± SD, median and interquartile range, or frequencies (number of cases) and percentages when appropriate. Comparison of numerical variables between the study groups was performed using the Student t-test for independent samples in comparing two groups when normally distributed and Mann–Whitney U-test for independent samples when not normally distributed. Comparison of numerical variables between more than two groups was performed using one-way analysis of variance test with post-hoc multiple two-group comparisons in normal data and Kruskal–Wallis test in non-normal data. For comparing categorical data, the χ2 -test was performed. Exact test was used instead when the expected frequency was less than 5. The correlations between the mean of 25(OH) D and other variables were analyzed by the Spearman correlation test. The statistical significant was considered as P value < 0.05.
The main demographic and laboratory parameters of our studied population are presented in Table 1. As shown in the table, we didn’t find any significant differences between BD patients and healthy control subjects regarding their age, gender, ALP, urea, Hb %, and platelets count (P > 0.05). On the other hand, there were significant differences as regards Calcium, ESR, CRP, WBCs and creatinine concentrations (P < 0.05).
The mean disease duration was 9.55 ± 6.60 years. At the time of blood sampling, the mean BDCAF activity score was 5.18 ± 3.59 (interquartile range 5), and the total BD severity score was 3.06 ± 2.9 (interquartile range 5). 55 of our patients had history of oral ulceration and 51 of them had a history of genital ulceration. The clinical characteristics of our patients are presented in Table 2.
Table 3 shows the mean ± SD of micronutrients of the diet of the BD and the control groups; the mean intake of vitamin D and calcium were below the RDA in BD group as compared to controls group (2.01 ± 0.65 µg versus 3.918 ± 0.37 µg) and (519.21 ± 70.61 mg versus 852.73 ± 24.72 mg) respectively, while mean vitamin A and mineral intake of iron, zinc and potassium were appropriate to the RDA requirements in both studied groups.
Plasma levels of 25-Hydroxy vitamin D and oxidative stress markers (MDA, NO, GSH, TAC and antioxidant enzymes “SOD and CAT activities”) are presented in Table 4. Plasma vitamin D levels were significantly lower in BD patients as compared to controls (14.6 ± 5.5 ng/ml) versus (24.5 ± 16.3 ng/ml, P = 0.002). Plasma CAT activity, GSH and TAC levels were significantly lower in BD patients (39.86 ± 16.45, 19.33 ± 11.32 and 0.43 ± 0.17,respectivelly) as compared to controls (66.94 ± 33.37, 9.93 ± 2.79 and 1.02 ± 0.44 respectively, P < 0.001). BD patients showed a non-significant decrease in plasma level of SOD activity than control. There was a significant increase in plasma MDA and NO levels in BD patients (7.14 ± 1.83, 82.48 ± 29.46, respectively) as compared to control (5.07 ± 2.99, 55.25 ± 26.79, P = 0.001, P < 0.001, respectively).
Plasma vitamin D concentrations were negatively correlated with BDCAF (r = − 0.3, P = 0.019), severity score (r = − 0.46, P < 0.001), ESR (r = − 0.28, P = 0.028), CRP(r = − 0.32, P < 0.012), MDA (r = − 0.58, P < 0.001) (Fig. 1) and NO (r = − 0.35, P = 0.005) (Fig. 2).There was a significant positive correlation between plasma vitamin D and Ca (r = 0.45, P < 0.001), SOD activity (r = 0.56, P < 0.001) (Fig. 3), GSH (r = 0.41, P = 0.001) (Fig. 4), and TAC (r = 0.45, P < 0.001) (Fig. 5). No significant correlation was seen between Plasma vitamin D levels and age, disease duration, Hb, WBCs, platelet, urea, creatinine, ALP and CAT activity (P > 0.05) (Table 5).
Severity of BD was graded as mild, moderate, and severe.Mild disease severity was found in 40 (66.6%) patients. Moderate disease severity was found in 14 (23.3%) patients. Severe disease was found in 6 (10.1%) patients. On comparing vitamin D level and oxidant/ antioxidant stress markers in the three groups with regard to disease severity. There were significant differences in Vitamin D level, MDA, SOD activity and TAC in the 3 groups (p = 0.002, 0.006, 0.012 and 0.035, respectively). No statistically significant difference was found in NO, CAT activity and GSH with regard to the disease severity (Table 6).
Behçet’s disease (BD) is a relatively uncommon systemic vasculitis characterized by oral and genital ulcers, ocular and skin lesions as well as other systemic manifestations, its prevalence in Egypt in a multicenter nationwide study on 1526 adult patients is 3.6/100,000 .
This study revealed significant decrease in vitamin D level between BD patients and healthy control subjects. Our results agree with other studies reporting vitamin D deficiency during BD . Moreover, serum vitamin D levels were found to be significantly in reverse associated with BDCAF and the severity score of BD. Our findings are in agreement with those previously observed by other researchers [19, 20].
We also found a significant decrease of vitamin D during severe stage of BD compared to mild and moderate stages. These results are consistent with the results observed by Zineb et al.  who found the incidence of vitamin D insufficiency (57.57%) during active stage of BD matched to inactive stage BD compared to inactive stage (27.27%) and healthy control. Our results also coincide with the results of Adeeb et al.  who stated that vitamin D levels tended to be lower among patients with active disease than among patients without active disease.
We also examined the oxidant / antioxidant markers in BD, there was a significant increase in plasma MDA and NO levels in BD patients, while plasma CAT activity, GSH and TAC levels were significantly lower in BD patients as compared to controls. Our findings are in agreement with several previous results [24,25,26]. The explanation for the lower level of antioxidant enzyme glutathione peroxidase (GSH-Px) in BD patients may be due to the release of superoxide radicals into the circulation,as well as superoxide radicals are produced in excessive amounts by neutrophils and ⁄or increase level of MDA in BD patients, as GSH-Px may become deactivated during oxidative stress,  and is blocked by MDA .
In the present study there were significant differences in MDA, SOD activity and TAC during severe stage of BD compared to mild and moderate stages while there was no statistically significant difference found in NO, CAT activity and GSH with regard to the disease severity. Pronai and Arimori  reported that the superoxide radical binding activity of plasma showed correlation with the activity of the disease. They suggested that the total antioxidant capacity (status) might be decreasing due to the release of superoxides by the PMNLs.
Our results are in agreement with Kiraz et al.  who found that serum NO levels were significantly higher in active BD patients than in inactive patients and controls, furthermore they found that their levels were normal in patients with inactive disease compared with controls. Also the pathogenesis of vasculitis in BD is due to NO-associated injury of tissues, especially of the endothelium. On the other hand, SOD may have a protective role against inflammation.
Furthermore, Evereklioglu et al.  found a statistically significant difference in serum NO between patients in active and inactive stages of the disease, as well as controls. They hypothesized that increased NO production was involved in the overall inflammatory process of BD and concluded that NO was linked to disease activity. Interestingly in another study, they noted high nitrite levels in patients’ plasma compared to control. During the active stage of the disease, NO production is higher. The monocyte/macrophage system was discovered in an early stage of chronic inflammation and was strongly involved in BD pathogenesis as the main cell source of high NO levels .
We found that plasma vitamin D levels were significantly inversely correlated with MDA and NO and was a significantly positively correlated with SOD activity, GSH and TAC while, there was no significant correlation between Plasma vitamin D levels and CAT activity. These results implied that vitamin D deficiency increase the oxidative stress in BD patients. Calcitriol has been shown to improve the ROS elimination pathway by increasing the intracellular pool of reduced GSH, partially through upstream regulation of the glutathione reductase (GR) &glutamate-cysteine ligase (GCL) genes . GCL is a vital enzyme in the production of GSH . Vitamin D and GSH concentrations have been found to have a beneficial relationship . Sardar et al.  proposed that vitamin D was an antioxidant as a result of an increase in hepatic GSH levels in rats given cholecalciferol. A clinical investigation found that a vitamin D and calcium supplementation combination was markedly reduced malondialdehyde (MDA) and led to a significant increase in plasma GSH & total antioxidant capacity levels compared to supplementation of either calcium and vitamin D separately .
Interestingly, there is evidence in the literature that vitamin D3 plays a major antioxidant role in mature erythrocytes. These findings not only confirm that cholecalciferol has an antioxidant effect , but also show that 1,25-dihydroxycholecalciferol may act as a direct antioxidant of membranes by stabilizing and protecting membranes from lipid peroxidation via interactions with their hydrophobic parts . Vitamin D3 was found to have an antioxidant impact greater than vitamin E, β -estradiol and melatonin in an in vitro study .
In conclusion our study is in agreement with previous studies that reported a decrease in circulating levels of vitamin D in several inflammatory diseases including systemic lupus erythematosus and familial Mediterranean fever [40, 41]. Furthermore, our findings demonstrate that the presence of lower levels of vitamin D is significantly correlated with the existence of an oxidative stress state in BD as shown by the increase of MDA, NO and the diminution of GSH, SOD activity, CAT activity and TAC. Foods rich or fortified with vitamin D, such as eggs, mushrooms, salmon, mackerel and fortified foods or beverages (eg, fortified breakfast cereals or fortified milk and juices) or supplementation can help in management BD related symptoms. It is a must to adjust intake of food enriched and/or fortified with vitamin D or to take a daily vitamin D supplement, that may improve oxidative stress and disease severity in BD.
Finally, there were some limitations to our study. First, despite describing the association between vitamin D deficiency and the antioxidant status, disease activity and severity in our patients, a causal relationship needs to be further investigated. Second, although we evaluated 25(OH) D levels in BD patients, we did not consider seasonal measurement, body mass index, physical activity and the effect of medical therapy. It would be interesting to investigate how the 25(OH) D level is dynamic in relation to the above mentioned factors as a complementary approach in a future study.
Availability of data and materials
The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.
Bozca BC, Alpsoy E. Experimental therapeutic solutions for Behcet’s disease. J Exp Pharmacol. 2021;13:127–45.
Takeno M, Kariyone AI, Yamashita N, Takiguchi M, Mizushima Y, Kaneoka H, et al. Excessive functions of peripheral blood neutrophils from patients with Behçet’s disease and from HLA B51 transgenic mice. Arthritis Rheum. 1995;3:426–33.
Niwa Y, Miyake S, Sakane T. Autooxidative damage in Behçet’s disease endothelial cell damage following the elevated oxygen radicals generated by stimulated neutrophils. Clin Exp Immunol. 1982;49:247–55.
Wei R, Christakos S. Mechanisms Underlying the Regulation of Innate and Adaptive Immunity by Vitamin D. Nutrients. 2015;7:8251–60.
Berridge MJ. Vitamin D cell signalling in health and disease. Biochem Biophys Res Commun. 2015;460:53–71.
-Adeeb F, Khan MU, Liu X, Stack AG, Devlin J, Fraser AD. High Vitamin D Levels May Downregulate Inflammation in Patients with Behçet’s Disease. International Journal of Inflammation Volume 2017, Article ID 8608716, 7 pages.
Lin AM, Chen K, Chao P. Antioxidative effect of vitamin D3 on zinc-induced oxidative stress in CNS. Ann N Y Acad Sci. 2005;1053:319–29.
-International Team for the Revision of the International Criteria for Behçet's Disease (ITR-ICBD). The International Criteria for Behçet's Disease (ICBD): a collaborative study of 27 countries on the sensitivity and specificity of the new criteria. J Eur Acad Dermatol Venereol. 2014;28(3):338–47.
Lawton G, Bhakta BB, Chamberlain MA, Tennant A. The Behcet’s disease activity index. Rheumatology (Oxford). 2004;43:73–8.
Bikle DD, Gee E, Halloran B, Kowalski MA, Ryzen E, Haddad JG. Assessment of the free fraction of 25-hydroxyvitamin D in serum and its regulation by albumin and the vitamin D-binding protein. J Clin Endocrinol Metab. 1986;63:954–9.
Kennel KA, Drake MT, Hurley DL. Vitamin D deficiency in adults: when to test and how to treat. Mayo Clin Proc. 2010;85:752–7.
Satoh K. Serum lipid peroxide in cerebrovascular disorders determined by a new colorimetric method. Clin Chim Acta. 1978;90(1):37–43.
Beauchamp C, Fridovich I. Superoxide dismutase: improved assays and an assay applicable to acrylamide gels. Anal Biochem. 1971;44(1):276–87.
Aebi H. Catalase in vitro. Methods Enzymol. 1984;105:121–6.
Beutler E, Duron O, Kelly BM. Improved method for the determination of blood glutathione. J Lab Clin Med. 1963;61:882–8.
Koracevic D, Koracevic G, Djordjevic V, Andrejevic S. Cosic V Method for the measurement of antioxidant activity in human fluids. J Clin Pathol. 2001;54:356–61.
Montgomery HAC, Dymock JF. The determination of nitrate. Analyst. 1961;86:414–6.
Gheita TA, El-Latif EA, El-Gazzar II, Samy N, Hammam N, Abdel Noor RA, El-Shebeiny E, El-Najjar AR, Eesa NN, Salem MN, Ibrahim SE, El-Essawi DF, Elsaman AM, Fathi HM, Sallam RA, El-Shereef RR, Abd-Elazeem MI, Said EA, Khalil NM, Shahin D, El-Saadany HM, ElKhalifa MS, Nasef SI, Abdalla AM, Noshy N, Fawzy RM, Saad E, Moshrif AH, El-Shanawany AT, Abdel-Fattah YH, Khalil HM. Egyptian College of Rheumatology-Behçet’s Disease Study Group (ECR-BDSG) Behçet’s disease in Egypt: a multicenter nationwide study on 1526 adult patients and review of the literature. Clin Rheumatol. 2019;38(9):2649–50. https://doi.org/10.1007/s10067-019-04653-8.
Hamzaoui K, Karray E, Sassi FH, Hamzaoui A. Vitamin D modulates peripheral immunity in patients with Behçet’s disease. Clin Exp Rheumatol. 2010;28(Suppl 60):S50–7.
Can M, Gunes M, Haliloglu OA, et al. Effect of vitamin D deficiency and replacement on endothelial functions in Behçet’s disease. Clin Exp Rheumatol. 2012;30:S57–61.
-Djerabaa Z, Benlabidib F, Djaballah-Idera FZ, Medjebera O, Arroul-Lammalia A, Belguendouza H, Otmanib F, Touil-Boukoffaa C. Vitamin D status in Algerian Behc¸et’s disease patients: an immunomodulatory effect on NO pathway. Immunopharmacol Immunotoxicol. 2017, ISSN: 0892–3973 (Print) 1532–2513.
Ganeb SS, Sabry HH, El-Assal MM, Kamal HM, Fayed AA. Vitamin D levels in patients with Behçet’s disease: significance and impact on disease measures. Egypt Rheumatol. 2013;35:151–7.
Jassim NA, Alrasool NHA, Gorial FL. Serum vitamin D level in Behçet’s disease: single center study from Iraq. Am J Med Sci Med. 2016;4:8–10.
Kose K, Yazici C, Cambay N, et al. Lipid peroxidation and erythrocyte antioxidant enzymes in patients with Behçet’s disease. Tohoku J Exp Med. 2002;197:9–16.
Buldanlioglu S, Turkmen S, Ayabakan HB, Yenice N, Vardar M, Dogan S, Mercan E. Nitric oxide, lipid peroxidation and antioxidant defence system in patients with active or inactive Behçet’s disease. Br J Dermatol. 2005;153:526–30.
Sandikci R, Turkmen S, Guvenen G, et al. Lipid peroxidation and antioxidant defence system in patients with active or inactive Behc¸et’s disease. Acta Derm Venereol (Stockh). 2003;83:342–6.
Blum J, Fridovich I. Inactivation of glutathione peroxidase by superoxide radical. Arch Biochem Biophys. 1985;240(500–8):20.
Arshad MAQ, Bhadra S, Cohen RM, Subbiah MTR. Plasma lipoprotein peroxidation potential: a test to evaluate individual susceptibility. Clin Chem. 1991;37:1756–8.
Pronai L, Arimori S. BG-104 enhances the decreased plasma superoxide scavenging activity in patients with Behcet’s disease, Sjo¨gren’s syndrome or haematological malignancy. Biotherapy. 1991;3:365–71.
Kiraz S, Ertenli I, Calguneri M, et al. Interactions of nitric oxide and superoxide dismutase in Behc¸et’s disease. Clin Exp Rheumatol. 2001;19(Suppl. 24):25–9.
Evereklioglu C, Turkoz Y, Er H, et al. Increased nitric oxide production in patients with Behçet’s disease: is it a new marker? J Am Acad Dermatol. 2002;46:50–4.
Orem A, Vanizor B, Cimsit G, et al. Decreased nitric oxide production in patients with Behçet’s disease. Dermatology. 1999;198:33–6.
Kanikarla-Marie P, Jain SK. 1, 25(OH)2D3 inhibits oxidative stress and monocyte adhesion by mediating the upregulation of GCLC and GSH in endothelial cells treated with acetoacetate (ketosis). J Steroid Biochem Mol Biol. 2016;159(94–101):37.
Lu SC. Regulation of glutathione synthesis. Mol Aspects Med. 2009;30:42–59.
Jain SK, Micinski D, Huning L, Kahlon G, Bass PF, Levine SN. Vitamin D and L-cysteine levels correlate positively with GSH and negatively with insulin resistance levels in the blood of type 2 diabetic patients. Eur J Clin Nutr. 2014;68:1148–53.
Sardar S, Chakraborty A, Chatterjee M. Comparative effectiveness of vitamin D3 and dietary vitamin E on peroxidation of lipids and enzymes of the hepatic antioxidant system in Sprague-Dawley rats. Int J Vitam Nutr Res. 1996;66:39–45.
Foroozanfard F, Jamilian M, Bahmani F, Talaee R, Talaee N, Hashemi T, et al. Calcium plus vitamin D supplementation influences biomarkers of inflammation and oxidative stress in overweight and vitamin D-deficient women with polycystic ovary syndrome: a randomized doubleblind placebo-controlled clinical trial. Clin Endocrinol. 2015;83:888–94.
Wolden-Kirk H, Gysemans C, Verstuyf A, Mathieu C. Extraskeletal effects of vitamin D. Endocrinol Metab Clin North Am. 2012;41(571–94):44.
Wiseman H. Vitamin D is a membrane antioxidant. Ability to inhibit iron-dependent lipid peroxidation in liposomes compared to cholesterol, ergosterol and tamoxifen and relevance to anticancer action. FEBS Lett. 1993;326:285–8.
Szodoray P, Tarr T, Bazso A, Poor G, Szegedi G, Kiss E, et al. The immunopathological role of vitamin D in patients with SLE: data from a single centre registry in Hungary. Scand J Rheumatol. 2011;40(2):122–6.
Kisacik B, Kaya SU, Pehlivan Y, Tasliyurt T, Sayarlioglu M, Onat AM. Decreased vitamin D levels in patients with familial mediterranean fever. Rheumatol Int. 2013;33(5):1355–7. https://doi.org/10.1007/s00296-011-2278-z (Epub 2011 Dec 21 PMID: 22187059).
The authors would like to thank the volunteer subjects for their participation in this study. We would also like to express our thanks to National Research Centre, Cairo, Egypt, Kasr Al Ainy Medical Hospital and The Medical Biochemistry department, Kasr Al Ainy Faculty of Medicine, Cairo University.
Open access funding provided by The Science, Technology & Innovation Funding Authority (STDF) in cooperation with The Egyptian Knowledge Bank (EKB). This study was funded by the authors personal contributions. The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.
Ethics approval and consent to participate
This study was approved by the Ethical Committee of Kasr Al Ainy Medical Hospital and was in accordance with the principles of Helsinki Declaration. The protocol of the study was approved by the NRC Ethics committee (Registration Number is20136) and all participants provided written informed consent.
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All participants provided written informed consent before participating in this study.
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Omar, H.S., Taha, F.M., Fouad, S. et al. The association between vitamin D levels and oxidative stress markers in Egyptian Behcet’s disease patients. Orphanet J Rare Dis 17, 264 (2022). https://doi.org/10.1186/s13023-022-02416-4