Serum homocysteine, folate and vitamin B12 levels in patients with psoriasis: a systematic review and meta-analysis

Association between Psoriasis and MTHFR polymorphisms: a systematic review and meta-analysis

Methylenetetrahydrofolate reductase (MTHFR) is key to the metabolism of folic acid, with loss of function mutations resulting in elevated homocysteine levels, a known risk factor for cardiovascular disease. Psoriasis patients may demonstrate hyperhomocysteinemia. To assess for the association between psoriasis and MTHFR C677T and A1298C polymorphisms. A systematic literature search was conducted in MEDLINE, Embase, Cochrane CENTRAL, and Web of Science. Case reports, case-control, cohort, and cross-sectional studies with full-text availability in English were considered. Meta-analysis was conducted with pooled ORs calculated via the random effects model (I2 > 50%). Of 917 records identified, 10 studies were selected for review of 1965 psoriasis patients and 2030 controls. Meta-analysis demonstrated that for MTHFR C677T, there were positive associations between psoriasis and the allele contrast model (C vs T, pooled OR = 1.69, 95% CI = 1.10-2.59), the additive model (CC vs TT, pooled OR = 2.44, 95% CI = 1.06-5.60), the dominant model (CC vs CT + TT, pooled OR = 1.77, 95% CI = 1.06-2.98), and the recessive model (CC + CT vs TT, pooled OR = 2.08, 95% CI = 1.05-4.13). For MTHFR A1298C, there were positive associations between psoriasis and the allele contrast model (A vs C, pooled OR = 3.57, 95% CI = 1.19-10.68), the dominant model (AA vs AC + CC, pooled OR = 4.44, 95% CI = 1.12-17.66), and the overdominant model (AC vs AA + CC, pooled OR = 0.26, 95% CI = 0.07-0.91). There may be a link between the C677T and A1298C polymorphisms with psoriasis diagnosis.

No causal effect of genetically determined circulating homocysteine levels on psoriasis in the European population: evidence from a Mendelian randomization study

Background

Although numerous studies demonstrated a link between plasma homocysteine (Hcy) levels and psoriasis, there still exists a certain level of controversy. Therefore, we conducted a Mendelian randomization study to investigate whether homocysteine plays a causative role in the development or exacerbation of psoriasis.

Methods

A two-sample Mendelian randomization (MR) analysis was conducted. Summary-level data for psoriasis were acquired from the latest R9 release results from the FinnGen consortium (9,267 cases and 364,071 controls). Single nucleotide polymorphisms (SNPs) robustly linked with plasma Hcy levels at the genome-wide significance threshold (p < 5 × 10-8) (18 SNPs) were recognized from the genome-wide meta-analysis on total Hcy concentrations (n = 44,147 participants) in individuals of European ancestry. MR analyses were performed utilizing the random-effect inverse variance-weighted (IVW), weighted median, and MR-Egger regression methods to estimate the associations between the ultimately filtrated SNPs and psoriasis. Sensitivity analyses were conducted to evaluate heterogeneity and pleiotropy.

Results

MR analyses revealed no causal effects of plasma Hcy levels on psoriasis [IVW: odds ratio (OR) = 0.995 (0.863-1.146), p = 0.941; weighed median method: OR = 0.985 (0.834-1.164), p = 0.862; MR-Egger regression method: OR = 0.959 (0.704-1.305), p = 0.795]. The sensitivity analyses displayed no evidence of heterogeneity and directional pleiotropy, and the causal estimates of Hcy levels were not influenced by any individual SNP.

Conclusion

Our study findings did not demonstrate a causal effect of genetically determined circulating Hcy levels on psoriasis.

The Role of Lifestyle and Nutrition in Psoriasis: Current Status of Knowledge and Interventions

Extrinsic environmental factors, including patient lifestyle (alcohol intake, smoking, stress, sleep disturbances, and sedentary habit), diet and single nutrients intake may affect psoriasis clinical presentation, severity, and course. All English language articles dealing with psoriasis and lifestyle factors or diet gathered by an extensive PubMed search were carefully examined in order to explore their impact on the disease. Current authoritative knowledge confirms that low‐calories, Mediterranean, and protein restricted/vegetarian diets may be beneficial. Psoriatic patients are also recommended to engage regular physical activity, to avoid alcohol intake and to consume fish rich in omega‐3 polyunsaturated fatty acids, as well as fruit and vegetables. Prebiotics and probiotics may also provide potential benefit, whereas vitamin D supplementation and gluten‐free diet are useful in selected cases only. Changing of dietary and lifestyle habits alone does not replace conventional treatment, but must be considered as an adjuvant. Physicians may play a crucial role, by adequately acknowledging psoriatic patients on the advantages of proper lifestyle and diet habits as well as providing clues to reliable sources of dietary advice.

Epidemiology of Psoriasis and Comorbid Diseases: A Narrative Review

Psoriasis is a chronic autoimmune inflammatory disease that remains active for a long period, even for life in most patients. The impact of psoriasis on health is not only limited to the skin, but also influences multiple systems of the body, even mental health. With the increasing of literature on the association between psoriasis and extracutaneous systems, a better understanding of psoriasis as an autoimmune disease with systemic inflammation is created. Except for cardiometabolic diseases, gastrointestinal diseases, chronic kidney diseases, malignancy, and infections that have received much attention, the association between psoriasis and more systemic diseases, including the skin system, reproductive system, and oral and ocular systems has also been revealed, and mental health diseases draw more attention not just because of the negative mental and mood influence caused by skin lesions, but a common immune-inflammatory mechanism identified of the two systemic diseases. This review summarizes the epidemiological evidence supporting the association between psoriasis and important and/or newly reported systemic diseases in the past 5 years, and may help to comprehensively recognize the comorbidity burden related to psoriasis, further to improve the management of people with psoriasis.

Buffering Adaptive Immunity by Hydrogen Sulfide

T cell-mediated adaptive immunity is designed to respond to non-self antigens and pathogens through the activation and proliferation of various T cell populations. T helper 1 (Th1), Th2, Th17 and Treg cells finely orchestrate cellular responses through a plethora of paracrine and autocrine stimuli that include cytokines, autacoids, and hormones. Hydrogen sulfide (H₂S) is one of these mediators able to induce/inhibit immunological responses, playing a role in inflammatory and autoimmune diseases, neurological disorders, asthma, acute pancreatitis, and sepsis. Both endogenous and exogenous H₂S modulate numerous important cell signaling pathways. In monocytes, polymorphonuclear, and T cells H₂S impacts on activation, survival, proliferation, polarization, adhesion pathways, and modulates cytokine production and sensitivity to chemokines. Here, we offer a comprehensive review on the role of H₂S as a natural buffer able to maintain over time a functional balance between Th1, Th2, Th17 and Treg immunological responses.

Risk of Psoriasis in Postgastrectomy Gastric Cancer Survivors: A Nationwide Population-Based Cohort Study

Background

Although patients with psoriasis have an increased risk of cancers, little is known about the risk of psoriasis in cancer patients.

Objective

We aimed to comparatively analyze the incidence and risk factors of psoriasis in gastric cancer patients who underwent gastrectomy and in the general population.

Methods

A nationwide retrospective cohort of 52,608 gastric cancer survivors (2007~2015) was compared to 123,438 matched controls from the general population to estimate the incidence and hazard ratio (HR) of new-onset psoriasis. We also calculated the HRs for psoriasis according to adjuvant cancer treatment, obesity, and vitamin B₁₂ supplementation in gastric cancer survivors.

Results

During a mean follow-up of 6.85 years, 645 of the 52,608 gastric cancer patients developed psoriasis, while 1,806 in the 123,438 matched control group developed psoriasis. Gastric cancer patients had a decreased risk of psoriasis (HR, 0.86; 95% confidence interval, 0.79~0.94), especially those who underwent subtotal gastrectomy. We found that vitamin B₁₂ supplementation for more than 3 years had an additive effect on decreasing the risk of psoriasis in gastric cancer patients who underwent subtotal gastrectomy. Total gastrectomy, radio/chemotherapy, and obesity did not affect the risk of psoriasis in gastric cancer survivors.

Conclusion

The incidence of psoriasis is slightly lower in gastric cancer survivors than in the general population. Our results suggest that the development of psoriasis may be reduced by removing the source of systemic inflammation caused by Helicobacter pylori infection through subtotal gastrectomy in gastric cancer survivors.

Homocysteine Is a Marker of Increased Cardio-Cerebrovascular Disease Risk in Psoriatic Patients, but It Does Not Reflect the Effect of Biological Therapy in the Longitudinal Observation

BACKGROUND

Psoriasis is linked to atherosclerosis. Homocysteine (HCYS) has been identified as a marker of increased risk of cardio-cerebrovascular diseases (CCVD) in population.

OBJECTIVE

The aim of the study was to determine whether elevated HCYS serves as a marker of increased CCVD in psoriasis and whether biological therapy for long-term monitoring influences HCYS levels.

METHODS

Clinical data, laboratory tests, and comorbid diagnoses were summarized for the two groups of patients based on entrance HCYS levels. Patients (n = 76) were included in the follow-up gradually over a period of 5 years.

RESULTS

The psoriatic patients with normal (54%) and elevated (46%) HCYS before biological treatment did not vary in clinical data, laboratory tests, treatment, and comorbid diagnoses apart from CCVD. Elevated HCYS group showed a four-fold excess of CCVD (OR 4.2, 95%CI 1.21-4.86, p=0.024). HCYS levels in the longitudinal observation did not vary.

CONCLUSION

An increased CCVD risk, independent of other risk factors, is present in psoriatic patients with elevated HCYS. The HCYS level was not influenced by biological therapy in longitudinal observation. Further studies are needed to explore if elevated HCYS could serve as a marker of increased CCVD in any stage of psoriasis and if it should be included in classical screening strategies.

Nutrition and psoriasis

Nutrition and dietary supplements are commonly used in the management of psoriasis; however, evidence of their efficacy is inconsistent. Although some dietary interventions have been shown to improve psoriasis consistently, others have little evidence supporting their use. We review common dietary interventions for the management of psoriasis and the evidence behind them. Caloric restriction, especially in overweight and obese individuals, has been shown to consistently diminish psoriatic activity. Evidence about other supplements and dietary interventions is inconsistent. Given the cost and side effects of pharmaceutical treatments for psoriasis, larger, long-term studies on the use of nutrition for the management of psoriasis are necessary.

Homocysteine and psoriasis

Psoriasis is caused by a complex interplay among the immune system, genetic background, autoantigens, and environmental factors. Recent studies have demonstrated that patients with psoriasis have a significantly higher serum homocysteine (Hcy) level and a higher prevalence of hyperhomocysteinaemia (HHcy). Insufficiency of folic acid and vitamin B₁₂ can be a cause of HHcy in psoriasis. Hcy may promote the immuno-inflammatory process in the pathogenesis of psoriasis by activating Th1 and Th17 cells and neutrophils, while suppressing regulatory T cells. Moreover, Hcy can drive the immuno-inflammatory process by enhancing the production of the pro-inflammatory cytokines in related to psoriasis. Hcy can induce nuclear factor kappa B activation, which is critical in the immunopathogenesis of psoriasis. There may be a link between the oxidative stress state in psoriasis and the effect of HHcy. Hydrogen sulfide (H₂S) may play a protective role in the pathogenesis of psoriasis and the deficiency of H₂S in psoriasis may be caused by HHcy. As the role of Hcy in the pathogenesis of psoriasis is most likely established, Hcy can be a potential therapeutic target for the treatment of psoriasis. Systemic folinate calcium, a folic acid derivative, and topical vitamin B12 have found to be effective in treating psoriasis.

Goeckerman Therapy of Psoriasis: Genotoxicity, Dietary Micronutrients, Homocysteine, and MTHFR Gene Polymorphisms

Goeckerman therapy (GT) of psoriasis vulgaris is based on the application of crude coal tar and ultraviolet radiation. We investigated DNA damage by the number of micronucleated binucleated cells (MNBC) in lymphocytes, serum homocysteine, vitamin B12, folic acid, and two polymorphisms (C677T and A1298C) in the MTHFR gene in 35 patients with exacerbated psoriasis vulgaris classified according to the psoriasis area and severity index (PASI) score and treated by GT. The median of PASI score decreased from nineteen to five, and MNBC increased from 10 to 18‰ after GT (p < 0.001 in both cases). Correlations of MNBC with homocysteine (Spearman’s rho = 0.420, p = 0.012) and vitamin B12 (rho = −0.389, p = 0.021) before the therapy were observed. Hyperhomocysteinemia was an independent predictor of genotoxicity (OR 9.91; 95% CI, 2.09–55.67; p = 0.003). Homocysteine was higher in females than in males (13 vs. 12 µmol/L, p = 0.045). In contrast, vitamin B12 levels in the females were lower than in the males (160 vs. 192 pmol/L, p = 0.047). Vitamin B12 in the females were negatively influenced by smoking status (160 pmol/L in smokers vs. 192 pmol/L in non-smokers, p = 0.025). A significantly higher MNBC was found in CC homozygous patients (A1298C polymorphism) than in AC heterozygotes (32 vs. 16‰, p = 0.005) and AA homozygotes (32 vs. 18‰, p = 0.036). Our data showed that homocysteine participates in the pathogenesis of psoriasis. Its serum levels correlated with MNBC and allowed the prediction of DNA damage to appear within GT. Both micronutrients status and homocysteine metabolic pathway contribute to the genotoxicity of GT.