Hyperhomocysteinemia, inflammation and autoimmunity

Dissecting hair breakage in alopecia areata: the central role of dysregulated cysteine homeostasis

In the initial stages of Alopecia Areata (AA), the predominance of hair breakage or exclamation mark hairs serves as vital indicators of disease activity. These signs are non-invasive and are commonly employed in dermatoscopic examinations. Despite their clinical salience, the underlying etiology precipitating this hair breakage remains largely uncharted territory. Our exhaustive review of the existing literature points to a pivotal role for cysteine-a key amino acid central to hair growth-in these mechanisms. This review will probe and deliberate upon the implications of aberrant cysteine metabolism in the pathogenesis of AA. It will examine the potential intersections of cysteine metabolism with autophagy, ferroptosis, immunity, and psychiatric manifestations associated with AA. Such exploration could illuminate new facets of the disease's pathophysiology, potentially paving the way for innovative therapeutic strategies.

Elevated serum homocysteine levels associated with poor recurrence-free and overall survival in patients with colorectal cancer

This study aimed to evaluate the significance of homocysteine (HCY) levels in predicting recurrence-free survival (RFS) and overall survival (OS) in colorectal cancer (CRC) patients. This retrospective study involved 1272 CRC patients. The risk of mortality increased with increasing HCY levels in CRC patients. The optimal HCY cutoff value in CRC patients was 15.2 μmol/L. The RFS (45.8% vs. 60.5%, p < 0.001) and OS (48.2% vs. 63.2%, p < 0.001) of patients with high HCY levels were significantly lower than those of patients with low HCY levels. Patients with high HCY levels were older, male, had large tumours, high carcinoembryonic antigen (CEA) levels, and long hospital stays, and incurred high hospitalisation costs. Multivariate analysis showed that when HCY levels exceeded 15.2 μmol/L, the risk of adverse RFS and OS increased by 55.7% and 61.4%, respectively. Subgroup analysis showed that HCY levels could supplement CEA levels and pathological staging. We constructed HCY-based prognostic nomograms, which demonstrated feasible discrimination and calibration values better than the traditional tumour, node, metastasis staging system for predicting RFS and OS. Elevated serum HCY levels were strongly associated with poor RFS and OS in CRC patients. HCY-based prognostic models are effective tools for a comprehensive evaluation of prognosis.

N-homocysteinylation of DJ-1 promotes neurodegeneration in Parkinson's disease

DJ-1, also known as Parkinson's disease protein 7 (Park7), is a multifunctional protein that regulates oxidative stress and mitochondrial function. Dysfunction of DJ-1 is implicated in the pathogenesis of Parkinson's disease (PD). Hyperhomocysteinemia is associated with an increased risk of PD. Here we show that homocysteine thiolactone (HTL), a reactive thioester of homocysteine (Hcy), covalently modifies DJ-1 on the lysine 182 (K182) residue in an age-dependent manner. The N-homocysteinylation (N-hcy) of DJ-1 abolishes its neuroprotective effect against oxidative stress and mitochondrial dysfunction, exacerbating cell toxicity. Blocking the N-hcy of DJ-1 restores its protective effect. These results indicate that the N-hcy of DJ-1 abolishes its neuroprotective effect and promotes the progression of PD. Inhibiting the N-hcy of DJ-1 may exert neuroprotective effect against PD.

Astragaloside Ⅳ negatively regulates Gpr97-TPL2 signaling to protect against hyperhomocysteine-exacerbated sepsis associated acute kidney injury

BACKGROUND

Hyperhomocysteine (HHcy) plays an important role in promoting inflammation and cell death of tubular epithelial cells. However, the role of HHcy and Astragaloside IV (AS-IV) in sepsis associated acute kidney injury (S-AKI) remain unclear.

PURPOSE

A significant aspect of this study aimed to elucidate the effect of AS-Ⅳ treatment on HHcy-exacerbated S-AKI and reveal its potential mechanism.

METHODS

Male C57BL/6 J mice fed with specific diet containing 2% methionine were established as in vivo models, and AS-Ⅳ was orally administrated continuously for 3 weeks, and then LPS (10 mg·kg-1 bodyweight) was given by a single intraperitoneal injection. The renal morphological changes were evaluated by HE and PAS staining. RNA-sequencing analysis was applied to select key signaling. The NRK-52E cells exposed to Hcy or combined with LPS were used as in vitro models. The mRNA and protein expression levels of Gpr97-TPL2 signaling were examined by qRT-PCR and western blotting assays.

RESULTS

In vivo, HHcy mice developed more severe renal injury and prevalent tubular inflammation after LPS injection. In vitro, the levels of NGAL, Gpr97 and TPL2 were significantly increased in NRK-52E cells induced by Hcy (1.6 mM) or in combination with LPS. Notably, the effects of Hcy on TPL2 signaling was abolished by transfecting TPL2 siRNA or treating TPL2 inhibitor, without alterations in Gpr97. However, the enhancement of Gpr97-TPL2 signaling induced by Hcy was counteracted by Gpr97 siRNA. Subsequently, our findings demonstrated that AS-Ⅳ treatment can improve renal function in HHcy-exacerbated S-AKI mice. Mechanistically, AS-Ⅳ alleviated renal tubular damage characterized by abnormal increases in KIM-1, NGAL, TPL2, Gpr97, Sema3A and TNF-α, and decreases in survivin in vivo and in vitro mainly through suppressing the activation of Gpr97-TPL2 signaling.

CONCLUSION

The present study suggested that HHcy-exacerbated S-AKI was mediated mechanically by activation of Gpr97-TPL2 signaling for the first time. Furthermore, our research also illustrated that AS-Ⅳ protected against HHcy-exacerbated S-AKI by attenuating renal tubular epithelial cells damage through negatively regulating Gpr97-TPL2 signaling, proposing a natural product treatment strategy for HHcy-exacerbated S-AKI.

Systemic immune-inflammation index and in-stent restenosis in patients with acute coronary syndrome: a single-center retrospective study

BACKGROUND

In-stent restenosis (ISR) has been shown to be correlated with inflammation. This study aimed to examine the relationship between systemic immune-inflammation index (SII, an innovative inflammatory biomarker) and ISR in acute coronary syndrome (ACS) patients after drug-eluting stent (DES) implantation.

METHODS

Subjects who were diagnosed with ACS and underwent DES implantation were enrolled retrospectively. All individuals underwent follow-up coronary angiography at six to forty-eight months after percutaneous coronary intervention (PCI). SII was defined as [(platelet count × neutrophil count)/lymphocyte count], and Ln-transformed SII (LnSII) was carried out for our analysis. Multivariate logistic regression analysis was employed to assess the association between LnSII and DES-ISR.

RESULTS

During a median follow-up period of 12 (11, 20) months, 523 ACS patients who underwent follow-up angiography were included. The incidence of DES-ISR was 11.28%, and patients in the higher LnSII tertile trended to show higher likelihoods of ISR (5.7% vs. 12.1% vs. 16.0%; P = 0.009). Moreover, each unit of increased LnSII was correlated with a 69% increased risk of DES-ISR (OR = 1.69, 95% CI 1.04-2.75). After final adjusting for confounders, a significant higher risk of DES-ISR (OR = 2.52, 95% CI 1.23-5.17) was found in participants in tertile 3 (≥ 6.7), compared with those in tertiles 1-2 (< 6.7). Subgroup analysis showed no significant dependence on age, gender, body mass index, current smoking, hypertension, and diabetes for this positive association (all P for interaction > 0.05).

CONCLUSION

High levels of SII were independently associated with an increased risk of DES-ISR in ACS patients who underwent PCI. Further prospective cohort studies are still needed to validate our findings.

Association Between Serum Homocysteine Concentration, Aneurysm Wall Inflammation, and Aneurysm Symptoms in Intracranial Fusiform Aneurysm

RATIONALE AND OBJECTIVES

The pathophysiology of fusiform intracranial aneurysm (FIA) involves inflammatory processes, and homocysteine plays a role in the inflammatory processes in the vessel wall. Moreover, aneurysm wall enhancement (AWE) has emerged as a new imaging biomarker of aneurysm wall inflammatory pathologies. To investigate the pathophysiological mechanisms of aneurysm wall inflammation and FIA instability, we aimed to determine the associations between the homocysteine concentration, AWE, and FIAs' related symptoms.

MATERIALS AND METHODS

We retrospectively reviewed the data of 53 patients with FIA who underwent both high-resolution magnetic resonance imaging and serum homocysteine concentration measurement. FIAs' related symptoms were defined as ischemic stroke or transient ischemic attack, cranial nerve compression, brainstem compression, and acute headache. The contrast ratio of the signal intensity of the aneurysm wall to the pituitary stalk (CRstalk) was used to indicate AWE. Multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were performed to determine how well the independent factors could predict FIAs' related symptoms. Predictors of CRstalk were also investigated. Spearman's correlation coefficient was used to identify the potential associations between these predictors.

RESULTS

Fifty-three patients were included, of whom 23 (43.4%) presented with FIAs' related symptoms. After adjusting for baseline differences in the multivariate logistic regression analysis, the CRstalk (odds ratio [OR]=3.207, P = .023) and homocysteine concentration (OR=1.344, P = .015) independently predicted FIAs' related symptoms. The CRstalk was able to differentiate between FIAs with and without symptoms (area under the ROC curve [AUC]=0.805), with an optimal cutoff value of 0.76. The homocysteine concentration could also differentiate between FIAs with and without symptoms (AUC=0.788), with an optimal cutoff value of 13.13. The combination of the CRstalk and homocysteine concentration had a better ability to identify symptomatic FIAs (AUC=0.857). Male sex (OR=0.536, P = .018), FIAs' related symptoms (OR=1.292, P = .038), and homocysteine concentration (OR=1.254, P = .045) independently predicted the CRstalk.

CONCLUSION

A higher serum homocysteine concentration and greater AWE indicate FIA instability. Serum homocysteine concentration may be a useful biomarker of FIA instability; however, this needs to be verified in future studies.

Uncovering the Hidden Dangers and Molecular Mechanisms of Excess Folate: A Narrative Review

This review delves into the intricate relationship between excess folate (vitamin B9) intake, especially its synthetic form, namely, folic acid, and its implications on health and disease. While folate plays a pivotal role in the one-carbon cycle, which is essential for DNA synthesis, repair, and methylation, concerns arise about its excessive intake. The literature underscores potential deleterious effects, such as an increased risk of carcinogenesis; disruption in DNA methylation; and impacts on embryogenesis, pregnancy outcomes, neurodevelopment, and disease risk. Notably, these consequences stretch beyond the immediate effects, potentially influencing future generations through epigenetic reprogramming. The molecular mechanisms underlying these effects were examined, including altered one-carbon metabolism, the accumulation of unmetabolized folic acid, vitamin-B12-dependent mechanisms, altered methylation patterns, and interactions with critical receptors and signaling pathways. Furthermore, differences in the effects and mechanisms mediated by folic acid compared with natural folate are highlighted. Given the widespread folic acid supplementation, it is imperative to further research its optimal intake levels and the molecular pathways impacted by its excessive intake, ensuring the health and well-being of the global population.

High plasma homocysteine level is associated with increased prevalence of the non-remission state in rheumatoid arthritis: Findings from the KURAMA cohort

OBJECTIVES

We aimed to determine the clinical impact of plasma homocysteine levels on disease activity and clinical remission in patients with rheumatoid arthritis (RA).

METHODS

A cross-sectional study was conducted using KURAMA (Kyoto University Rheumatoid Arthritis Management Alliance) database. We enrolled 291 female patients, who were treated in a treat-to-target manner. We measured plasma total homocysteine using a liquid chromatography-tandem mass spectrometry system and collected clinical data including a 28-joint RA disease activity score-erythrocyte sedimentation rate (DAS28-ESR). Clinical remission of disease activity was defined as a DAS28-ESR < 2.6.

RESULTS

In a univariable analysis, the plasma homocysteine concentration was significantly and positively associated with DAS-28-ESR and was higher in the non-remission group than in the remission group. The cutoff value of the plasma homocysteine level was calculated to be 7.9 nmol/mL by the test of the receiver operating characteristic curve analysis. In a multivariable analysis, after adjusting for clinically relevant variables, the high homocysteine level remained a significant positive association for DAS28-ESR (estimate 0.27, P = .0019) and a positive factor for the presence of RA non-remission (odds ratio 2.39, P = .0071).

CONCLUSIONS

Increased plasma homocysteine levels showed a significant positive association with current disease activity and the non-remission state in female patients with RA under treat-to-target treatment. The findings suggest the potential utility of plasma homocysteine as a disease state marker reflecting conditions that are treatment failure and difficult to remission and may provide clinical evidence on the interplay between homocysteine and inflammatory activation in RA.

Parkinson's Disease Risk and Hyperhomocysteinemia: The Possible Link

Parkinson's disease (PD) is one of the most common degenerative brain disorders caused by the loss of dopaminergic neurons in the substantia nigra (SN). Lewy bodies and -synuclein accumulation in the SN are hallmarks of the neuropathology of PD. Due to lifestyle changes and prolonged L-dopa administration, patients with PD frequently have vitamin deficiencies, especially folate, vitamin B6, and vitamin B12. These disorders augment circulating levels of Homocysteine with the development of hyperhomocysteinemia, which may contribute to the pathogenesis of PD. Therefore, this review aimed to ascertain if hyperhomocysteinemia may play a part in oxidative and inflammatory signaling pathways that contribute to PD development. Hyperhomocysteinemia is implicated in the pathogenesis of neurodegenerative disorders, including PD. Hyperhomocysteinemia triggers the development and progression of PD by different mechanisms, including oxidative stress, mitochondrial dysfunction, apoptosis, and endothelial dysfunction. Particularly, the progression of PD is linked with high inflammatory changes and systemic inflammatory disorders. Hyperhomocysteinemia induces immune activation and oxidative stress. In turn, activated immune response promotes the development and progression of hyperhomocysteinemia. Therefore, hyperhomocysteinemia-induced immunoinflammatory disorders and abnormal immune response may aggravate abnormal immunoinflammatory in PD, leading to more progression of PD severity. Also, inflammatory signaling pathways like nuclear factor kappa B (NF-κB) and nod-like receptor pyrin 3 (NLRP3) inflammasome and other signaling pathways are intricate in the pathogenesis of PD. In conclusion, hyperhomocysteinemia is involved in the development and progression of PD neuropathology either directly via induction degeneration of dopaminergic neurons or indirectly via activation of inflammatory signaling pathways.

N-homocysteinylation of α-synuclein promotes its aggregation and neurotoxicity

The aggregation of α-synuclein plays a pivotal role in the pathogenesis of Parkinson's disease (PD). Epidemiological evidence indicates that high level of homocysteine (Hcy) is associated with an increased risk of PD. However, the molecular mechanisms remain elusive. Here, we report that homocysteine thiolactone (HTL), a reactive thioester of Hcy, covalently modifies α-synuclein on the K80 residue. The levels of α-synuclein K80Hcy in the brain are increased in an age-dependent manner in the TgA53T mice, correlating with elevated levels of Hcy and HTL in the brain during aging. The N-homocysteinylation of α-synuclein stimulates its aggregation and forms fibrils with enhanced seeding activity and neurotoxicity. Intrastriatal injection of homocysteinylated α-synuclein fibrils induces more severe α-synuclein pathology and motor deficits when compared with unmodified α-synuclein fibrils. Increasing the levels of Hcy aggravates α-synuclein neuropathology in a mouse model of PD. In contrast, blocking the N-homocysteinylation of α-synuclein ameliorates α-synuclein pathology and degeneration of dopaminergic neurons. These findings suggest that the covalent modification of α-synuclein by HTL promotes its aggregation. Targeting the N-homocysteinylation of α-synuclein could be a novel therapeutic strategy against PD.

Association of homocysteine-related subcortical brain atrophy with white matter lesion volume and cognition in healthy aging

Homocysteine (Hcy) is a vascular risk factor associated with cognitive impairment and cerebrovascular disease but has also been implicated in Alzheimer's disease (AD). Using multivariate Scaled Subprofile Model (SSM) analysis, we sought to identify a network pattern in structural neuroimaging reflecting the regionally distributed association of plasma Hcy with subcortical gray matter (SGM) volumes and its relation to other health risk factors and cognition in 160 healthy older adults, ages 50-89. We identified an SSM Hcy-SGM pattern that was characterized by bilateral hippocampal and nucleus accumbens volume reductions with relative volume increases in bilateral caudate, pallidum, and putamen. Greater Hcy-SGM pattern expression was associated with greater white matter hyperintensity (WMH) volume, older age, and male sex, but not with other vascular and AD-related risk factors. Mediation analyses revealed that age predicted WMH volume, which predicted Hcy-SGM pattern expression, which, in turn, predicted cognitive processing speed performance. These findings suggest that the multivariate SSM Hcy-SGM pattern may be indicative of cognitive aging, reflecting a potential link between vascular health and cognitive dysfunction in healthy older adults.

Plasma lipid profiles and homocysteine levels in anti-N-methyl-D-aspartate receptor encephalitis

Introduction

We aimed to investigate whether lipid profiles and homocysteine levels in patients with anti-N-methyl-D-aspartate receptor encephalitis are related to clinical presentation and prognosis, which may contribute to further research on the pathogenesis and treatment of this disease.

Methods

This study included a total of 43 patients with anti-N-methyl-D-aspartate receptor encephalitis and 43 sex-age-matched healthy controls. Baseline demography, clinical data, patient outcomes, and ancillary examination results were recorded. Patients were followed up every 2-3 months during the first year. The modified Rankin Scale score was used to evaluate the therapeutic effect and clinical outcome.

Results

Among the 43 patients included in this study, 55.81% were male, the mean age of onset was 27 years old, and the median modified Rankin Scale score on admission was 3.0. Apolipoprotein A-1 was significantly lower in patients with anti-N-methyl-D-aspartate receptor encephalitis compared with healthy controls (p = 0.004). Compared with healthy controls, homocysteine (p = 0.002), apolipoprotein B (p = 0.004), Lpa (p = 0.045), and apolipoprotein B/apolipoprotein A-1 (p = 0.001) were significantly increased in patients with anti-N-methyl-D-aspartate receptor encephalitis. According to the modified Rankin Scale scores, 6 months after discharge, 72.09% of patients had a good prognosis and 27.91% had a poor prognosis. In the good prognosis group, age (p = 0.031), lipoprotein a (p = 0.023), apolipoprotein A-1 (p = 0.027) at baseline, and the modified Rankin Scale score on admission (p = 0.019) were significantly higher than those in the poor prognosis group.

Conclusion

This study suggests the possibility that serum lipid profile and homocysteine play an important role in the pathogenesis of anti-N-methyl-D-aspartate receptor encephalitis, providing support for lipid-lowering treatment of anti-N-methyl-D-aspartate receptor encephalitis patients.

Variation of homocysteine levels in rheumatoid arthritis patients: relationship to inflammation, cardiovascular risk factors, and methotrexate

BACKGROUND

The aim of this study was to evaluate the variation of homocysteine (Hcy) levels in patients with rheumatoid arthritis (RA) and to analyze the relationship to inflammatory parameters, cardiovascular risk, and methotrexate (MTX).

METHODS

This cross-sectional study assessed disease activity and treatment in RA patients. The European League Against Rheumatism (EULAR) 2015 HeartSCORE was performed for cardiovascular (CV) risk estimation and levels of plasma Hcy, serum folate concentrations, vitamin B12, and erythrocyte sedimentation rate (ESR) were measured.

RESULTS

A total of 103 participants with mean age 53 ± 10 years and mean disease duration 10.55 ± 7.34 years were included. Patients were treated with MTX in 69.9% of cases and corticosteroid in 80.5% of cases. Of all patients, 13% had a cardiovascular inheritance, 25% were hypertensive, and 18% had diabetes. The EULAR 2015 HeartSCORE was high and very high (≥5%) in 35% of cases. Mean Hcy level was 12.54 ± 4.2 µmol/L [6.89-32.92] and hyperhomocysteinemia was noted in 20.4% of patients. Analytic study demonstrated that hyperhomocysteinemia was associated with male gender (p = 0.01), MTX use (p = 0.01), smoking (p = 0.008), renal failure (p = 0.04), and high disease activity (p = 0.05), but there was no association with the HeartSCORE (p = 0.23). Hcy level was negatively correlated with folate (p = 0.009) and vitamin B12 level (p = 0.02) and positively with age (p = 0.01), C‑reactive protein (CRP; p = 0.05), and Simplified Disease Activity Index (SDAI; p = 0.03). In multivariate logistic regression analysis, current MTX use, levels of vitamin B12 and creatine, and Clinical Disease Activity Index (CDAI) appeared to be independent factors associated with hyperhomocysteinemia.

CONCLUSION

MTX use, CDAI, and the levels of vitamin B12 and creatine are independent factors associated with hyperhomocysteinemia.

Dietary Methionine via Dose-Dependent Inhibition of Short-Chain Fatty Acid Production Capacity Contributed to a Potential Risk of Cognitive Dysfunction in Mice

High-methionine diets induce impaired learning and memory function, dementia-like neurodegeneration, and Alzheimer's disease, while low-methionine diets improve learning and memory function. We speculated that variations in intestinal microbiota may mediate these diametrically opposed effects; thus, this study aimed to verify this hypothesis. The ICR mice were fed either a low-methionine diet (LM, 0.17% methionine), normal methionine diet (NM, 0.86% methionine), or high-methionine diet (HM, 2.58% methionine) for 11 weeks. We found that HM diets damaged nonspatial recognition memory, working memory, and hippocampus-dependent spatial memory and induced anxiety-like behaviors in mice. LM diets improved nonspatial recognition memory and hippocampus-dependent spatial memory and ameliorated anxiety-like behavior, but the differences did not reach a significant level. Moreover, HM diets significantly decreased the abundance of putative short-chain fatty acid (SCFA)-producing bacteria (Roseburia, Blautia, Faecalibaculum, and Bifidobacterium) and serotonin-producing bacteria (Turicibacter) and significantly increased the abundance of proinflammatory bacteria Escherichia-Shigella. Of note, LM diets reversed the results. Consequently, the SCFA and serotonin levels were significantly decreased with HM diets and significantly increased with LM diets. Furthermore, HM diets induced hippocampal oxidative stress and inflammation and selectively downregulated the hippocampus-dependent memory-related gene expression, whereas LM diets selectively upregulated the hippocampus-dependent memory-related gene expression. In conclusion, dietary methionine via dose-dependent inhibition of SCFA production capacity contributed to a potential risk of cognitive dysfunction in mice.

The effect of low-molecular-weight heparin on live birth rate of patients with unexplained early recurrent pregnancy loss: A two-arm randomized clinical trial

BACKGROUND

The effect of anticoagulant medication in unexplained early recurrent pregnancy loss (RPL) patients is controversial. This clinical trial evaluated the effect of low-molecular-weight heparin (LMWH) on pregnancy outcomes in these patients.

MATERIALS AND METHODS

The study was performed as a single-blind randomized clinical trial between 2016 and 2018. Samples were selected from patients who were referred to Avicenna RPL clinic with a history of at least two previously happened early unexplained miscarriages. The eligibility was defined strictly to select unexplained RPL patients homogenously. One hundred and seventy-three patients who got pregnant recently were allocated randomly into two groups LMWH plus low-dose aspirin treatment (Group A = 85) and low-dose aspirin treatment only (Group B = 88)) and were followed up till their pregnancy termination (delivery/abortion). A per-protocol analysis was carried out and all statistical tests were two-sided with a P < 0.05 significance level.

RESULTS

The live birth rates (LBRs) in Groups A and B were 78% and 77.1%, respectively, which did not show any statistically significant difference between the two groups, neither in rates nor in time of abortion. In subgroup analysis for polycystic ovary syndrome (PCOS) patients, the odds ratio for study outcome (intervention/control) was 2.25 (95% confidence interval: 0.65-7.73). There was no major adverse event whereas minor bleeding was observed in 18% of patients in Group A.

CONCLUSION

LMWH does not improve the LBR in unexplained RPL patients, however, it is recommended to evaluate its effect separately in PCOS patients.

Lowering serum homocysteine in H-type hypertensive patients with atrial fibrillation after radiofrequency catheter ablation to prevent atrial fibrillation recurrence

Background

Prior investigation revealed that elevated serum total homocysteine (tHcy) are strongly correlated with atrial fibrillation (AF) recurrence. Herein, the goal of this study was to elucidate whether folic acid (FA) treatment reduced AF recurrence following radiofrequency catheter ablation (RFCA).

Methods

To conduct this retrospective research, we included consecutive H-type hypertensive AF patients, who were treated with first RFCA, between January 2010 and January 2022. We assessed the AF recurrence risk between patients who were taking 10 mg enalapril and 0.8 mg FA in a single-pill combination (enalapril–FA) daily and those who were taking a pill of 10 mg enalapril only. Outcomes were compared using the propensity-score matched analysis. Cox regression model was employed for the evaluation of AF recurrence events.

Results

Out of 2,714 patients, 645 patients receiving enalapril and 282 patients receiving enalapril-FA were included for analysis. Following propensity score matching, 239 patients remained in each group. These patients were followed-up for a median of 379 (137–596) days, and revealed that the enalapril-FA patients had drastically reduced AF recurrence, compared to the enalapril patients [adjusted hazard ratio (HR), 0.68; 95% confidence interval (CI), 0.48–0.97; P = 0.029]. Apart from this, no interactions were detected in the subgroup analysis.

Conclusion

In H-type hypertensive AF patients who were treated with first RFCA, FA supplementation was correlated with a reduced AF recurrence risk.

Homocysteine and the Mortality of Critically Ill Patients: A Meta-Analysis

Prevalence of hyperhomocysteinemia (HHcy) is high in critically ill patients. However, the association between serum homocysteine level and outcomes of the critically ill patients remains unknown. We performed a meta-analysis of cohort studies to comprehensively evaluate the above association. Relevant cohort studies were identified by search of electronic databases including PubMed, Embase, Web of Science, Wanfang, and CNKI from the inception of the databases to February 5, 2022. A randomized-effect model incorporating the possible between-study heterogeneity was used to pool the results. Overall, 16 cohorts with 1663 critically ill patients who were admitted to the intensive care unit (ICU) were involved in the meta-analysis. Pooled results showed that compared to non-survivors of the critical illnesses, survivors had significantly lower serum level of Hcy at ICU admission [mean difference (MD): -3.42 μmol/l, 95% confidence interval (CI): -5.89 to 0.94, p=0.007; I2=86%]. Subgroup analysis showed that the difference of Hcy between survivors and non-survivors was significant in Asian patients (MD: -8.17 μmol/l, p<0.001), but not in non-Asians (MD: 0.30 μmol/l, p=0.62; p for subgroup difference<0.001). Moreover, meta-analysis with seven cohorts, all including Chinese patients, showed that HHcy at ICU admission was independently associated with a higher risk of all-cause mortality in critically ill patients (odds ratio: 2.99, 95% CI: 2.26 to 3.97, p<0.001; I2=69%). A higher serum level of Hcy at ICU admission may be associated with an increased risk of all-cause mortality in critically ill patients, particularly in the Chinese population.

The assessment of the cardiovascular risk in rheumatoid arthritis patients on anti TNF therapy

Auto-immune rheumatic diseases are characterised by high levels of inflammation that accelerate the development of atherosclerosis, increasing the cardiovascular risk. Direct evaluation of arteries such as of intima media thickness measurement is a simple test that asesses the cerebral and cardiovascular risk. In the initial stages, an increase of the intimal media thickness can be observed. Later on, atherosclerosis (plaques), stenosis and occlusion of the arteries can be identified. Indirect evaluation of the cardiovascular risk can be performed using serological markers - fibrinogen, C reactive protein, estimated sedimentation rate, total cholesterol, low density lipoproteins and high density lipoproteins, homocysteine levels etc. The presence of certain lifestyle factors that increase the risk, such as smoking, sedentarism and associated pathologies such as obesity, diabetes, hypertension were assesed in patients with rheumatoid arthritis. The aim of the study is to prove the relationship between anti-tumor necrosis factor alpha therapy effect on the cardiovascular risk in rheumatoid arthritis patients

Relationships of Serum Homocysteine, Vitamin B12, and Folic Acid Levels with Papulopustular Rosacea Severity: A Case-Control Study

Background

Rosacea is a chronic inflammatory skin disease with a multifactorial etiology. Recently, associations between serum homocysteine (Hcy) levels and inflammatory skin diseases, such as psoriasis and hidradenitis suppurativa, have been reported. However, no study has explored the levels of serum Hcy, folic acid, and vitamin B₁₂ in patients with rosacea.

Objective

To investigate serum Hcy, vitamin B₁₂, and folic acid levels in patients with papulopustular rosacea (PPR), we characterized the association of these levels with PPR severity.

Methods

This case-control study included 138 PPR patients and 58 healthy controls. The serum levels of Hcy, vitamin B₁₂, and folic acid were measured. A correlation was assessed between disease severity and serum levels of Hcy, vitamin B₁₂, and folic acid.

Results

Serum vitamin B₁₂ and folic acid levels were significantly lower in PPR patients than in the healthy controls (p = 0.011 and p = 0.0173, respectively). Although serum Hcy levels did not significantly differ between PPR patients and healthy controls, PPR severity was positively correlated with serum Hcy levels (p < 0.001).

Conclusions

Our results suggest a possible association between hyperhomocysteinemia and vitamin B₁₂ deficiency in patients with PPR.

Fetal hyperhomocysteinemia is associated with placental inflammation and early breakdown of maternal-fetal tolerance in Pre-term birth

PROBLEM

Hyperhomocysteinemia (hypHcy) due to impaired folate metabolism is shown to be a risk factor for preterm birth (PTB) and low birth weight (LBW) in mothers. However, the relationship of fetal hypHcy with adverse pregnancy outcomes is under-represented. The present study aims to investigate the association of fetal hypHcy with oxidative stress and placental inflammation that can contribute to an early breakdown of maternal-fetal tolerance in pre-term birth (PTB).

METHODS

Cord blood and placenta tissue were collected from PTB and term infant group. Levels of homocysteine, folic acid, vitamin B12 and oxidative stress markers (MDA, T-AOC, 8-OHdG) were measured in cord blood serum using ELISA and respective standard assay kits. Relative expression of candidate genes (TNF-α, IL-6, IL1-β, VEGF-A, MMP2 and MMP9) was also checked using RT-PCR and immunoblotting/immunohistochemistry.

RESULTS

PTB infants showed significantly higher levels of homocysteine (p = 0.02) and lower levels of vitamin B12 (p = 0.005) as compared to term infants. We also found that PTB infants with hypHcy had lower T-AOC (p = 0.003) and higher MDA (p = 0.04) levels as compared to term infants with normal homocysteine levels. The mRNA and protein levels of TNF-α, VEGF-A, MMP2 and MMP9 were significantly higher in hypHcy PTB infants.

CONCLUSION

Our results show that fetal hypHcy is associated with oxidative stress and an increase in inflammatory markers in the placenta. Thus, in conclusion, our study demonstrates that fetal hypHcy during pregnancy is a potential risk factor that may initiate an early breakdown of uterine quiescence due to activation of inflammatory processes leading to PTB. This article is protected by copyright. All rights reserved.

Blood Thiol Redox State in Chronic Kidney Disease

Thiols (sulfhydryl groups) are effective antioxidants that can preserve the correct structure of proteins, and can protect cells and tissues from damage induced by oxidative stress. Abnormal levels of thiols have been measured in the blood of patients with moderate-to-severe chronic kidney disease (CKD) compared to healthy subjects, as well as in end-stage renal disease (ESRD) patients on haemodialysis or peritoneal dialysis. The levels of protein thiols (a measure of the endogenous antioxidant capacity inversely related to protein oxidation) and S-thiolated proteins (mixed disulphides of protein thiols and low molecular mass thiols), and the protein thiolation index (the molar ratio of the S-thiolated proteins to free protein thiols in plasma) have been investigated in the plasma or red blood cells of CKD and ESRD patients as possible biomarkers of oxidative stress. This type of minimally invasive analysis provides valuable information on the redox status of the less-easily accessible tissues and organs, and of the whole organism. This review provides an overview of reversible modifications in protein thiols in the setting of CKD and renal replacement therapy. The evidence suggests that protein thiols, S-thiolated proteins, and the protein thiolation index are promising biomarkers of reversible oxidative stress that could be included in the routine monitoring of CKD and ESRD patients.

PROTEOLYTIC ACTIVITY IN THE HEART OF RATS WITH HYPERHOMOCYSTEINEMIA

OBJECTIVE

The aim: To investigate the distribution of proteolytic activity and cytokine profile in the heart of rats with hyperhomocysteinemia.

PATIENTS AND METHODS

Materials and methods: A total of 60 albino non-linear male rats was used in the study. Hyperhomocysteinemia was induced by intragastric administration of DL-homocysteine thiolactone. Total proteolytic activity was measured using casein as a substrate. To determine the activity of metal-dependent and serine proteases, ethylenediaminetetraacetic acid, and phenylmethylsulfonyl fluoride were used. The level of matrix metalloproteinases, tissue inhibitor of metalloproteinases-1, and cytokines was studied by enzyme-linked immunosorbent assay.

RESULTS

Results: It was found an increase in the total proteolytic activity in the heart of young, adult, and old animals. In addition, the redistribution of proteolytic activity was revealed - the portion of metal-dependent enzymes increased in all groups while the percentage of serine proteases decreased in the old animals with hyperhomocysteinemia. The state of mild inflammation, evidenced by the increased level of some pro-inflammatory cytokines, was found in the heart of young and old animals with hyperhomocysteinemia.

CONCLUSION

Conclusions: The pathogenesis of hyperhomocysteinemia is accompanied by a change in the proteolytic activity in the heart as well as a change in the cytokine profile.

The Effects of Folic Acid Supplementation on Pro-inflammatory Mediators: a Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials

PURPOSE

Despite extensive research, findings regarding the effects of folic acid supplementation on inflammatory mediators have been controversial and inconclusive. This study therefore aimed to summarize the findings of all available clinical trials regarding the effects of folic acid supplementation on inflammatory biomarkers in adults.

METHODS

A systematic search was conducted of PubMed/MEDLINE, Scopus, Web of Science, EMBASE, and Google Scholar until April 2020. All randomized controlled trials that examined the influence of folic acid supplementation on C-reactive protein, interleukin 6 (IL-6), and tumor necrosis factor-α (TNF-α) were included. Pooled effect sizes were calculated based on the random effects model, and dose-response analysis was modeled by using a fractional polynomial model.

FINDINGS

In total, 18 randomized controlled trials involving 2286 participants were analyzed. Folic acid supplementation significantly reduced serum levels of C-reactive protein (mean difference [MD], -0.21 mg/L; 95% CI, -0.41 to -0.01; n = 16), TNF-α (MD, -14.88 pg/mL; 95% CI, -23.68 to -6.09; n = 10), and IL-6 (MD, -0.93 pg/mL; 95% CI, -1.72 to -0.14; n = 11). Subgroup analyses suggested a significant reduction at doses ≤5 mg/d and studies longer than 12 weeks in duration. A significant nonlinear association was also found between folic acid dosage (P_nonlinearity <0.001) and duration of administration (P_nonlinearity <0.001) with serum TNF-α levels.

IMPLICATIONS

This meta-analysis indicates the beneficial effects of folic acid supplementation on pro-inflammatory cytokines. Further studies with a longer duration of administration, higher doses, and larger sample sizes should be performed exclusively on patients with chronic inflammatory disorders to elucidate the favorable role of folate intake on inflammatory biomarkers. International Prospective Register of Systematic Reviews identifier: CRD42021249947.

TGFB3-AS1 promotes Hcy-induced inflammation of macrophages via inhibiting the maturity of miR-144 and upregulating Rap1a

It has been demonstrated that homocysteine (Hcy) can cause inflammatory diseases. Long noncoding RNAs (lncRNA) and microRNAs (miRNAs) are involved in this biological process, but the mechanism underlying Hcy-induced inflammation remains poorly understood. Here, we found that lncRNA TGFB3-AS1 was highly expressed in macrophages treated with Hcy and the peripheral blood monocytes from cystathionine beta-synthase heterozygous knockout (CBS^+/−) mice with a high-methionine diet using lncRNA microarray. In vivo and in vitro experiments further confirmed that TGFB3-AS1 accelerated Hcy-induced inflammation of macrophages through the Rap1a/wnt signaling pathway. Meanwhile, TGFB3-AS1 interacted with Rap1a and reduced degradation of Rap1a through inhibiting its ubiquitination in macrophages treated with Hcy. Rap1a mediated inflammation induced by Hcy and serves as a direct target of miR-144. Moreover, TGFB3-AS1 regulated miR-144 by binding to pri-miR-144 and inhibiting its maturation, which further regulated Rap1a expression. More importantly, we found that high expression of TGFB3-AS1 was positively correlated with the levels of Hcy and proinflammatory cytokines in serum of healthy individuals and patients with HHcy. Our study revealed a novel mechanism by which TGFB3-AS1 promoted inflammation of macrophages through inhibiting miR-144 maturation to stay miR-144 regulated inhibition of functional Rap1a expression.

Autoimmune Rheumatic Diseases and Vascular Function: The Concept of Autoimmune Atherosclerosis

Autoimmune rheumatic diseases (AIRDs) with unknown etiology are increasing in incidence and prevalence. Up to 5% of the population is affected. AIRDs include rheumatoid arthritis, system lupus erythematosus, systemic sclerosis, and Sjögren's syndrome. In patients with autoimmune diseases, the immune system attacks structures of its own body, leading to widespread tissue and organ damage, which, in turn, is associated with increased morbidity and mortality. One third of the mortality associated with autoimmune diseases is due to cardiovascular diseases. Atherosclerosis is considered the main underlying cause of cardiovascular diseases. Currently, because of finding macrophages and lymphocytes at the atheroma, atherosclerosis is considered a chronic immune-inflammatory disease. In active inflammation, the liberation of inflammatory mediators such as tumor necrotic factor alpha (TNFa), interleukine-6 (IL-6), IL-1 and other factors like T and B cells, play a major role in the atheroma formation. In addition, antioxidized, low-density lipoprotein (LDL) antibodies, antinuclear antibodies (ANA), and rheumatoid factor (RF) are higher in the atherosclerotic patients. Traditional risk factors like gender, age, hypercholesterolemia, smoking, diabetes mellitus, and hypertension, however, do not alone explain the risk of atherosclerosis present in autoimmune diseases. This review examines the role of chronic inflammation in the etiology-and progression-of atherosclerosis in autoimmune rheumatic diseases. In addition, discussed here in detail are the possible effects of autoimmune rheumatic diseases that can affect vascular function. We present here the current findings from studies that assessed vascular function changes using state-of-the-art techniques and innovative endothelial function biomarkers.

Effect of introducing biologics to patients with rheumatoid arthritis on the risk of venous thromboembolism: a nationwide cohort study

In the United States, 100,000-300,000 patients die from venous thromboembolism (VTE) each year, with more than 500,000 people related hospitalizations. While in Europe, 500,000 people die from VTE each year. Patients with rheumatoid arthritis are at increased risk of VTE. The use of biologics in patients with rheumatoid arthritis may be associated with an increased risk of VTE. We identified all patients who had been newly approved for Catastrophic Illness Card of rheumatoid arthritis extracted the claims data from the National Health Insurance research database and Registry for Catastrophic Illness Patient Database from 2003 to 2016. VTE was defined as the presence of inpatient VTE diagnostic codes (including DVT or PE) according to the discharge diagnosis protocol. An analysis of VTE variables indicated that the incidence of VTE in the biologic group (14.33/10,000 person-years) was higher than that in the conventional drug group (12.61/10,000 person-years). As assessed by the Cox proportional hazards model, the relative HR for VTE in the biologic group (HR: 1.11; 95% CI 0.79-1.55) versus that in the conventional drug group did not reach a significant difference. In conclusion, this study found no significant differences in risk were observed between the use of conventional DMARDs and biologics.

Homocysteine and Age-Related Central Nervous System Diseases: Role of Inflammation

Hyperhomocysteinemia (HHcy) is remarkably common among the aging population. The relation between HHcy and the development of neurodegenerative diseases, such as Alzheimer's disease (AD) and eye diseases, and age-related macular degeneration (AMD) and diabetic retinopathy (DR) in elderly people, has been established. Disruption of the blood barrier function of the brain and retina is one of the most important underlying mechanisms associated with HHcy-induced neurodegenerative and retinal disorders. Impairment of the barrier function triggers inflammatory events that worsen disease pathology. Studies have shown that AD patients also suffer from visual impairments. As an extension of the central nervous system, the retina has been suggested as a prominent site of AD pathology. This review highlights inflammation as a possible underlying mechanism of HHcy-induced barrier dysfunction and neurovascular injury in aging diseases accompanied by HHcy, focusing on AD.

Association of homocysteine with ankylosing spondylitis: a systematic review and meta-analysis

Background

Hyperhomocysteinemia is associated with autoimmune diseases such as ankylosing spondylitis (AS), systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA). Current findings regarding plasma/serum homocysteine (HCY) levels in AS patients are inconsistent. This study aims to systematically evaluate the association between circulating HCY levels and AS.

Methods

Online electronic databases (PubMed, Web of Science, Embase, ScienceDirect, China National Knowledge Infrastructure (CNKI), and Wanfang data) were used to retrieve all relevant articles published up to May 7, 2020. The pooled standardized mean difference (SMD) with 95% confidence interval (CI) was calculated using the random-effect model, Stata16 software.

Results

Nine articles containing 778 AS patients and 522 controls were included in this meta-analysis. No significant differences in HCY levels were found between AS and control groups (pooled SMD = 0.46, 95% CI = − 0.30 to 1.23, P = 0.23). However, subgroup analysis suggested that HCY levels were significantly higher (P < 0.05) in the AS group treated with methotrexate (MTX) compared with the control group. In contrast, HCY levels were significantly (P < 0.05) lower in the AS group receiving anti-TNF-α treatment compared with the control group. No significant differences were detected between HCY levels and disease activity scores (Bath AS disease activity index, BASDAI), and methylenetetrahydrofolate reductase (MTHFR) C677T genotype.

Conclusion

This meta-analysis indicates that HCY levels are similar between AS and controls, and do not correlate with disease activity. However, different medical treatments cause fluctuations of circulating HCY levels in AS patients. Further and larger-scale studies are needed to confirm these findings.

Trial registration

This study was registered at international prospective register of systematic reviews (PROSPERO), registration number: CRD42020184426.

Folic acid ameliorates palmitate-induced inflammation through decreasing homocysteine and inhibiting NF-κB pathway in HepG2 cells

OBJECTIVE

Prevention of inflammation is one of the possible remedy procedure for steatohepatitis during NAFLD. In this study, we researched the folic acid (FA) potency to attenuate the inflammation of palmitate-treated HepG2 cells and the related signalling pathways.

METHODS

The molecular mechanisms related to FA anti-inflammatory effect in palmitate and Hcy-treated HepG2 cell line were assessed.

RESULTS

The results indicated that while palmitate enhances the expression and secretion of TNF-α, IL-6, and IL-1β, and also intracellular ROS level, FA at concentrations of 25, 50, and 75 µg/mL significantly reversed these effects in HepG2 cells. In addition, FA could ameliorate inflammation and decrease ROS production induced by Hcy. Furthermore, FA pre-treatment suppress palmitate -induced (NF-κB) p65 level in palmitate or Hcy stimulated cells.

CONCLUSIONS

Overall, these results suggest that FA reduces inflammation in HepG2 cells through decreasing ROS and Hcy concentration level resulting in inhibiting the NF-κB pathway.

Gut microbiota and the periodontal disease: role of hyperhomocysteinemia

Periodontal disease is one of the most common conditions resulting from poor oral hygiene and is characterized by a destructive process in the periodontium that essentially includes gingiva, alveolar mucosa, cementum, periodontal ligament, and alveolar bone. Notably, the destructive event in the alveolar bone has been linked to homocysteine (Hcy) metabolism; however, it has not been fully investigated. Therefore; the implication of Hcy towards initiation, progression, and maintenance of the periodontal disease remains incompletely understood. Higher levels of Hcy (also known as hyperhomocysteinemia (HHcy)) exerts deleterious effects on gum health and teeth in distinct ways. Firstly, increased production of proinflammatory cytokines such as TNF-α, IL-1β, IL-6, and IL-8 leads to an inflammatory cascade of events that affect methionine (Met) and Hcy metabolism (i.e., 1-carbon metabolism) leading to HHcy. Secondly, metabolic dysregulation during chronic medical conditions increases systemic inflammation leading to a decrease in vitamins, more specifically B6, B12, and folic acid, that play important roles as cofactors in Hcy metabolism. Also, given the folate level in the HHcy state that is important during dysbiosis, these two conditions appear to be intimately related, and in this context, HHcy-induced dysbiosis may be one of the potential causes of periodontal disease. This paper sums up the link between periodontitis and HHcy, with a special emphasis on the "oral-gut microbiome axis" and the potential probiotic intervention towards warding off some of the serious periodontal disease conditions.

Hyperhomocysteinemia is Associated with Inflammation, Bone Resorption, Vitamin B12 and Folate Deficiency and MTHFR C677T Polymorphism in Postmenopausal Women with Decreased Bone Mineral Density

Osteoporosis is an age-related bone disease, affecting mainly postmenopausal women, characterized by decreased bone mineral density (BMD) and consequent risk of fractures. Homocysteine (Hcy), a sulfur-aminoacid whose serum level is regulated by methylenetrahydrofolate reductase (MTHFR) activity and vitamin B12 and folate as cofactors, is a risk factor for inflammatory diseases. Literature data concerning the link between Hcy and osteoporosis are still debated. The aim of our study was to assess the relationship among Hcy and BMD, inflammation, vitamin status and bone turnover in postmenopausal osteoporosis. In 252 postmenopausal women, BMD was measured by dual-energy X-ray absorptiometry (DXA). In addition to serum Hcy, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and bone turnover markers (bone alkaline phosphatase-BAP, osteocalcin-OC, C-terminal telopeptide of type I collagen (CTX), vitamin deficiencies and MTHFR-C677T polymorphism were evaluated. Hcy, inflammation, bone resorption markers and prevalence of C677T polymorphism were higher, whereas vitamin D, B12, folate, and bone formation markers were lower in women with decreased BMD compared to those with normal BMD. Our results suggest a significant association between Hcy, BMD and inflammation in postmenopausal osteoporosis. The regulation of Hcy overproduction and the modulation of the inflammatory substrate could represent additional therapeutic approaches for osteoporosis prevention.

The effect of the systemic folic acid intake as an adjunct to scaling and root planing on clinical parameters and homocysteine and C-reactive protein levels in gingival crevicular fluid of periodontitis patients: A randomized placebo-controlled clinical trial

AIM

To evaluate clinical and biochemical effects of adjunctive systemic folic acid (FA) intake with scaling and root planing (SRP) in periodontitis treatment.

MATERIALS AND METHODS

Sixty periodontitis subjects (30 per group) were randomly assigned into study groups and treated with either SRP + placebo (SRP + P) or SRP + folic acid (SRP + F). In addition to clinical parameters (plaque index [PI], gingival index [GI], probing pocket depth [PPD], clinical attachment level [CAL] and gingival recession [GR]), gingival crevicular fluid (GCF) samples were obtained at baseline and post-treatment (PT) periods (one (PT-1), three (PT-3) and six (PT-6) months) for C-reactive protein (CRP) and homocysteine (Hcy) evaluation.

RESULTS

Significant time-dependent reduction was detected at all clinical parameters for both groups (p < .001). Compared to SRP + P, CAL was lower in SRP + F at PT-1 (p = .004) and PT-3 (p = .035), whereas GR was lower at only PT-1 (p = .015). GCF volume and CRP did not show inter-group differences, whereas Hcy was higher in SRP + F at PT-3 (p = .044) and PT-6 (p = .041). GCF volume and Hcy showed reduction after treatment in both groups (p < .001).

CONCLUSION

Both modalities exhibited clinical improvement and change in biochemical parameters. Adjunctive systemic FA intake may be recommended adjunctive to periodontitis treatment to reveal better outcomes. However, its impact mechanisms should be further enlightened.

Methylenetetrahydrofolate reductase polymorphism in healthy volunteers and its correlation with homocysteine levels in patients with thrombosis

OBJECTIVE:

To determine prevalence of methylenetetrahydrofolate reductase (MTHFR) mutations in apparently healthy individuals residing in Mumbai and patients with deep vein thrombosis (DVT) and coronary artery disease (CAD) and to correlate these polymorphisms with homocysteine (Hcy) levels.

MATERIALS AND METHODS:

This case–control study was initiated after receiving ethical approval and following the participant's written consent. One hundred and twenty unmatched healthy volunteers and 240 patients with arterial and venous thrombosis were enrolled. The prevalence of C677T and A1298C MTHFR mutations was detected using polymerase chain reaction-restriction fragment length polymorphism technique. Serum Hcy concentration and lipid levels were determined using biochemical kits.

RESULTS:

Allele frequency of 677T was 7%, 15%, and 14% in healthy controls, DVT, and CAD patients, respectively, while for 1298C allele, it was 31%, 33%, and 29%, respectively. The lipid markers in CAD patients were significantly low in comparison to the controls while the Hcy level in patients with thrombosis was higher in comparison with the controls. Highest Hcy levels were observed in participants with TT genotype followed by CT genotype and CC genotype in all the three groups. A higher risk of raised Hcy levels was seen in the variants (CT + TT) as compared to CC genotype in DVT (odds ratio [OR] = 3.39, 95% confidence interval [CI] = 1.39–8.2,P < 0.01) and CAD (OR = 21.67, 95%CI = 4.87–96.47,P < 0.0001). The risk observed for A1298C was 2.28 and 2.12 times higher in variants (AC + CC) of both DVT and CAD (OR = 2.28, 95%CI = 1.09–4.75 and OR = 2.12, 95%CI = 1.02–4.40, respectively).

CONCLUSIONS:

The prevalence of variants was more in thrombosis patients as compared to unmatched controls. Our study highlights the fact that MTHFR C677T polymorphism as compared to A1298C significantly affects Hcy levels in patients with thrombosis indicating that patients with mutant variants are at higher risk of rapid progression of their disease condition.

Homocysteine Induces Inflammation in Retina and Brain

Homocysteine (Hcy) is an amino acid that requires vitamins B₁₂ and folic acid for its metabolism. Vitamins B₁₂ and folic acid deficiencies lead to hyperhomocysteinemia (HHcy, elevated Hcy), which is linked to the development of diabetic retinopathy (DR), age-related macular degeneration (AMD), and Alzheimer’s disease (AD). The goal of the current study was to explore inflammation as an underlying mechanism of HHcy-induced pathology in age related diseases such as AMD, DR, and AD. Mice with HHcy due to a lack of the enzyme cystathionine-β-synthase (CBS) and wild-type mice were evaluated for microglia activation and inflammatory markers using immuno-fluorescence (IF). Tissue lysates isolated from the brain hippocampal area from mice with HHcy were evaluated for inflammatory cytokines using the multiplex assay. Human retinal endothelial cells, retinal pigment epithelial cells, and monocyte cell lines treated with/without Hcy were evaluated for inflammatory cytokines and NFκB activation using the multiplex assay, western blot analysis, and IF. HHcy induced inflammatory responses in mouse brain, retina, cultured retinal, and microglial cells. NFκB was activated and cytokine array analysis showed marked increase in pro-inflammatory cytokines and downregulation of anti-inflammatory cytokines. Therefore, elimination of excess Hcy or reduction of inflammation is a promising intervention for mitigating damage associated with HHcy in aging diseases such as DR, AMD, and AD.

Serum/plasma homocysteine levels in patients with systemic lupus erythematosus: a systematic review and meta-analysis

Published studies have shown contradictory results in the association of serum/plasma levels of homocysteine (HCY) with systemic lupus erythematosus (SLE). This study is to systematically evaluate the association of serum/plasma HCY levels in SLE. A search was done using PubMed, Embase, Web of Science, and ScienceDirect databases up to 7 April 2019. Thirty-six articles including 2919 SLE patients and 3120 healthy controls were finally included in this meta-analysis. The HCY levels were significantly higher in SLE patients than in healthy controls (P < 0.001). The subgroup analysis revealed that Asian, African, Arab, Mixed, White and others as well as ages (< 35 and ≥ 35) had significant higher HCY levels in SLE patients than in the healthy controls. The study indicated that patients with disease activity index scores < 8 (P < 0.001) and ≥ 8 (P = 0.003) of SLE had significant higher HCY levels as compared with the healthy controls. It was also revealed that disease duration in SLE patients for < 10 and ≥ 10 years (P < 0.001) had significant higher HCY levels as compared with the healthy controls. A significant higher HCY level for body mass index (< 23 and ≥ 23) was found as well as measurement type in SLE patients than healthy controls. This meta-analysis demonstrated higher HCY levels in patients with SLE than healthy controls, suggesting a possible role of HCY in the disease.Key Points• Homocysteine (HCY) is closely related to the mechanisms of systemic lupus erythematosus (SLE).• This study reveals a significant correlation between HCY levels and the various indexes of disease activity.• This study reveals that medication may influence HCY levels in SLE.• This study also discovers that the subgroup analysis of all the factors influences the HCY levels in SLE patients.

Hyperhomocysteinemia and myocardial remodeling in the sand rat, Psammomys obesus

OBJECTIVE

Numerous studies have shown that a methionine-rich diet induces hyperhomocysteinemia (Hhcy), a risk factor for cardiovascular diseases. The objective of the present study was to determine the involvement of Hhcy in cardiac remodeling in the sand rat Psammomys obesus.

MATERIALS AND METHODS

An experimental Hhcy was induced, in the sand rat Psammomys obesus, by intraperitoneal injection of 300 mg/kg of body weight/day of methionine for 1 month. The impact of Hhcy on the cellular and matricial structures of the myocardium was analyzed with histological techniques (Masson trichrome and Sirius red staining). Immunohistochemistry allowed us to analyze several factors involved in myocardial remodeling, such as fibrillar collagen I and III, metalloproteases (MMP-2 and -9) and their inhibitors (TIMP-1 and -2), TGF-β1 and activated caspase 3.

RESULTS

Our results show that Hhcy induced by an excess of methionine causes, in the myocardium of Psammomys obesus, a significant accumulation of fibrillar collagens I and III at the interstitial and perivascular scales, indicating the appearance of fibrosis, which is associated with an immuno-expression increase of TGF-β1, MMP-9 and TIMP-2 and an immuno-expression decrease of MMP-2 and TIMP-1. Also, Hhcy induces apoptosis of some cardiomyocytes and cardiac fibroblasts by increasing of activated caspase 3 expression. These results highlight a remodeling of cardiac tissue in hyperhomocysteinemic Psammomys obesus.

Elevated Plasma Homocysteine Levels in Anti-N-methyl-D-aspartate Receptor Encephalitis

Objective: Homocysteine (Hcy) levels have been investigated in many diseases, such as neurodegenerative and autoimmune diseases. However, changes in Hcy levels in anti-N-Methyl-D-aspartate receptor (anti-NMDAR) encephalitis have not been investigated thus far.

Methods: Case data were collected from 45 patients with anti-NMDAR encephalitis and 179 age- and sex-matched healthy controls (HCs). Clinical characteristics, Hcy levels, C reactive protein (CRP) levels, and cerebrospinal fluid (CSF) parameters were determined. Association of Hcy and clinical parameters were evaluated in these patients. Among these 45 patients, 15 had a follow-up evaluation at 3 months after treatment.

Results: Hcy levels (p < 0.001) and CRP levels (p = 0.005) from the patients with anti-NMDAR encephalitis were significantly higher than those from HCs. Hcy levels from male patients were significantly lower than those from male HCs (p < 0.001). Comparing anti-NMDAR encephalitis patients after treatment with before treatment, the former has significantly higher Hcy levels (p = 0.004), CRP levels (p = 0.041) and mRS scores (p = 0.002). Furthermore, a significant negative correlation between the changes in Hcy levels and the changes in mRS scores (r = −0.534, p = 0.040) was observed.

Conclusion: Elevated plasma homocysteine occurs in anti-NMDAR encephalitis, and seems associated with male sex.

Polymorphisms C677T and A1298C of MTHFR Gene: Homocysteine Levels and Prothrombotic Biomarkers in Coronary and Pulmonary Thromboembolic Disease

The activity of the enzyme methylenetetrahydrofolate reductase (MTHFR) determines homocysteine (Hcy) levels, and polymorphisms in its gene affect the activity of the enzyme. Changes in the enzyme's activity may lead to a higher susceptibility to develop arterial and venous thromboembolic disease. The aim was to analyze the relationship between the C677T and A1298C polymorphisms of MTHFR, Hcy levels, and prothrombotic biomarkers in pulmonary embolism (PE) and acute myocardial ischemia (AMI). Clinical files of patients with thromboembolic diseases having complete data and whose doctor had requested an assay to determine the polymorphisms of the MTHFR gene, Hcy levels, and prothrombotic biomarkers were studied to search for the correlation between mutations of the MTHFR gene and Hcy levels in the different diseases. We included 334 files: 158 were from women and 176 from men (51 [19 SD] years). Sixty-three percent have had thrombosis, 8% AMI, and 31% PE. Patients with thrombosis had elevated frequency of the C677T polymorphism. The CC genotype was higher than the TT genotype ( P = .003) and CT versus the TT ( P = .009). In patients with PE, the CC genotype was higher than the TT genotype ( P = .038). Pulmonary embolism with massive and submassive events had predominant genotypes 677 TT ( P = .003) and the AA 1298 ( P = .017). Elevated Hcy levels in the presence of the T allele in the C677T gene and of the A allele in the A1298C gene are associated with AMI and massive and submassive PE.

Homocysteine levels are independently associated with damage accrual in systemic lupus erythematosus patients from a Latin-American cohort

OBJECTIVE

To determine the impact of homocysteine levels on damage accrual in systemic lupus erythematosus (SLE) patients.

METHODS

This longitudinal study was conducted in consecutive patients seen every 6 months at our Rheumatology Department since 2012. Patients with available homocysteine levels and who had at least one subsequent visit were included. Univariable and multivariable Cox regression models were done to determine if homocysteine levels were predictive of damage accrual as per the SLICC Damage Index (SDI). The multivariable model was adjusted for pertinent variables (age at diagnosis, gender, socioeconomic status, disease duration, disease activity (SLEDAI), Framingham score, antimalarial and immunosuppressive drug use, average daily dose, and exposure time to prednisone (PDN)).

RESULTS

One hundred forty-five patients were included; their mean (SD) age at diagnosis was 43.70 (12.09) years, 136 (93.8%) were female, and nearly all were Mestizo. At baseline, disease duration was 7.55 (6.73) years; patients were followed for 3.54 (1.27) years. The SLEDAI was 5.60 (4.34), and the SDI 0.97 (1.35). The average daily PDN dose was 7.30 (5.78) mg/day and the time of PDN exposure was 7.36 (6.73) years. Mean homocysteine levels were 10.07 (3.71) μmol/L. The highest tertile of homocysteine levels predicted new damage accrual in the univariable and multivariable models [HR 1.78 (95% CI, 1.042-3.039); p = 0.035 and HR 2.045 (95% CI, 1.077-3.883); p = 0.029, respectively]. Increased levels (> 15 μmol/L) were found in 12 (8.3%) patients; 75 (51.7%) patients increased ≥ 1 SDI point.

CONCLUSION

In SLE patients, homocysteine levels predicted damage accrual independently of other well-known risk factors for such occurrence.

Serum homocysteine, folate, and vitamin B12 levels in patients with vitiligo and their potential roles as disease activity biomarkers: A systematic review and meta-analysis

BACKGROUND

Hyperhomocysteinemia and folate and vitamin B₁₂ deficiencies have been reported in patients with vitiligo. Investigating the role of these conditions might shed light on the pathogenesis of vitiligo.

OBJECTIVE

To perform a systematic review and meta-analysis of studies assessing serum homocysteine, folate, and vitamin B₁₂ levels in vitiligo patients.

METHODS

Online databases were searched on May 15, 2018, to identify studies comparing serum homocysteine, folate, and vitamin B₁₂ levels between patients with vitiligo and controls. A random effects model was used.

RESULTS

Twenty-two studies involving a total of 1448 patients with vitiligo were included. Patients with vitiligo had significantly higher serum homocysteine levels (standardized mean difference [SMD] 0.550, 95% confidence interval [CI] 0.262-0.838; I² 87.3%) and lower vitamin B₁₂ levels (SMD -0.430, 95% CI -0.738 to -0.121; I² 85.3%) than controls. Serum folate levels were not significantly different between the 2 groups (SMD -0.240, 95% CI -0.592 to 0.111; I² 85.5%). A subgroup analysis revealed that these findings correlated with disease activity.

LIMITATIONS

The included studies were heterogeneous. Serum homocysteine levels could be influenced by various factors.

CONCLUSION

Patients with vitiligo have higher serum homocysteine levels and lower vitamin B₁₂ levels than individuals without vitiligo.

Gene-Metabolite Interaction in the One Carbon Metabolism Pathway: Predictors of Colorectal Cancer in Multi-Ethnic Families

For personalized healthcare, the purpose of this study was to examine the key genes and metabolites in the one-carbon metabolism (OCM) pathway and their interactions as predictors of colorectal cancer (CRC) in multi-ethnic families. In this proof-of-concept study, we included a total of 30 participants, 15 CRC cases and 15 matched family/friends representing major ethnic groups in southern California. Analytics based on supervised machine learning were applied, with the target variable being specified as cancer, including the ensemble method and generalized regression (GR) prediction. Elastic Net with Akaike's Information Criterion with correction (AICc) and Leave-One-Out cross validation GR methods were used to validate the results for enhanced optimality, prediction, and reproducibility. The results revealed that despite some family members sharing genetic heritage, the CRC group had greater combined gene polymorphism-mutations than the family controls (p < 0.1) for five genes including MTHFR C677T, MTHFR A1298C, MTR A2756G, MTRR A66G, and DHFR 19bp. Blood metabolites including homocysteine (7 µmol/L), methyl-folate (40 nmol/L) with total gene mutations (≥4); age (51 years) and vegetable intake (2 cups), and interactions of gene mutations and methylmalonic acid (MMA) (400 nmol/L) were significant predictors (all p < 0.0001) using the AICc. The results were validated by a 3% misclassification rate, AICc of 26, and >99% area under the receiver operating characteristic curve. These results point to the important roles of blood metabolites as potential markers in the prevention of CRC. Future intervention studies can be designed to target the ways to mitigate the enzyme-metabolite deficiencies in the OCM pathway to prevent cancer.

Hyperhomocysteinemia in acute iatrogenic hypothyroidism: the relevance of thyroid autoimmunity

PURPOSE

Hyperhomocysteinemia is a known cardiovascular risk factor and a key player in the inflammatory activation of autoimmune diseases. Hashimoto's thyroiditis (HT) is the leading cause of hypothyroidism which, in itself, has been associated with a significant raise of homocysteine (Hcy) levels and increased cardiovascular risk. Our aim was to assess the impact of HT on Hcy levels in patients with acute hypothyroidism.

METHODS

We prospectively enrolled 121 patients (mean age: 46 years, F/M = 102/19) with acute post-surgical hypothyroidism. Based on the presence of anti-thyroid antibodies and the histological description of an inflammatory infiltrate, 26 and 95 patients were classified as HT and non-HT, respectively. Several parameters including thyroid-stimulating hormone (TSH), levels of serum free T3 and free T4, weight, glucose levels, total cholesterol, creatinine, vitamin B₁₂, ferritin and erythrocyte sedimentation rate were obtained from all patients and correlated with Hcy levels.

RESULTS

Median Hcy level in the whole cohort was 16.8 µmol/L (normal values: < 12 µmol/l). Among all parameters analysed, only Hcy levels were significantly different between HT and non-HT patients (median Hcy = 19.7 vs 16.2 µmol/L, respectively; p = 0.018, Mann-Whitney U test). Analysis of covariance showed the presence of HT to be the strongest predictor of Hcy levels (coefficient = 0.25534, p = 0.001). Serum TSH was not significantly associated with Hcy levels (p = 0.943).

CONCLUSION

In patients with iatrogenic hypothyroidism, those with HT have significantly higher Hcy levels than those without HT. The increase of Hcy levels appears to be mainly determined by the HT-related immune-inflammatory condition.

Meta-analysis of homocysteine-related factors on the risk of colorectal cancer

The major objective of this meta-analysis was to examine the association between homocysteine and related measurements with the risk of colorectal cancer (CRC) and adenomatous polyps (AP). Many studies presented an association between methyltetrahydrofolate reductase (MTHFR) gene polymorphisms and risk of CRC. Yet, there have been variances on what homocysteine-related and dietary factors play on the risk of CRC or AP, in association with folate-related one carbon metabolism pathways. We pooled analyses to examine comprehensively all homocysteine related factors including blood tests measurements, dietary, and lifestyle factors for their associations with the risk of CRC and AP. We located 86 articles published from 1995 to 2017. The results revealed that elevated homocysteine levels and decreased vitamin B12 levels in the blood were associated with increased risks of CRC and AP, with case-control studies having greater significant effect sizes compared to that of cohort-control studies. Decreased methionine and vitamin B6 levels in the blood increased the risk of CRC. MTHFR 677 TT and CT polymorphisms were interacting with elevated homocysteine levels to increase the risk of CRC. Decreased dietary fiber, methionine, vitamin B9 or folate, and vitamin B6 intakes were associated with increased risks of CRC; whereas, increased dietary B12 intake, alcohol intake, and smoking were associated with increased risk of CRC. Further studies can be conducted to examine the mechanistic differences of blood levels of homocysteine-related and dietary factors, including different types of dietary fiber, for their effects on decreasing the homocysteine toxicity to prevent CRC.

Asymmetric Dimethyl Arginine as a Biomarker of Atherosclerosis in Rheumatoid Arthritis

Cardiovascular disease is the main cause of morbidity and mortality in rheumatoid arthritis (RA). Despite the advent on new drugs targeting the articular manifestations, the burden of cardiovascular disease is still an unmet need in the management of RA. The pathophysiology of accelerated atherosclerosis associated to RA is not yet fully understood, and reliable and specific markers of early cardiovascular involvement are still lacking. Asymmetric dimethylarginine is gaining attention for its implication in the pathogenesis of endothelial dysfunction and as biomarkers of subclinical atherosclerosis. Moreover, the metabolic pathway of methylarginines offers possible targets for therapeutic interventions to decrease the cardiovascular risk. The purpose of this review is to describe the main causes of increased methylarginine levels in RA, their implication in accelerated atherosclerosis, the possible role as biomarkers of cardiovascular risk, and finally the available data on current pharmacological treatment.

Hypermethylation: Causes and Consequences in Skeletal Muscle Myopathy

A detrimental consequence of hypermethylation is hyperhomocysteinemia (HHcy), that causes oxidative stress, inflammation, and matrix degradation, which leads to multi-pathology in different organs. Although, it is well known that hypermethylation leads to overall gene silencing and hypomethylation leads to overall gene activation, the role of such process in skeletal muscle dysfunction during HHcy condition is unclear. In this study, we emphasized the multiple mechanisms including epigenetic alteration by which HHcy causes skeletal muscle myopathy. This review also highlights possible role of methylation, histone modification, and RNA interference in skeletal muscle dysfunction during HHcy condition and potential therapeutic molecules, putative challenges, and methodologies to deal with HHcy mediated skeletal muscle dysfunction. We also highlighted that B vitamins (mainly B12 and B6), with folic acid supplementation, could be useful as an adjuvant therapy to reverse these consequences associated with this HHcy conditions in skeletal muscle. However, we would recommend to further study involving long-term trials could help to assess efficacy of the use of these therapeutic agents. J. Cell. Biochem. 118: 2108-2117, 2017. © 2017 Wiley Periodicals, Inc.

Homocysteine Induces Glial Reactivity in Adult Rat Astrocyte Cultures

Astrocytes are dynamic glial cells associated to neurotransmitter systems, metabolic functions, antioxidant defense, and inflammatory response, maintaining the brain homeostasis. Elevated concentrations of homocysteine (Hcy) are involved in the pathogenesis of age-related neurodegenerative disorders, such as Parkinson and Alzheimer diseases. In line with this, our hypothesis was that Hcy could promote glial reactivity in a model of cortical primary astrocyte cultures from adult Wistar rats. Thus, cortical astrocytes were incubated with different concentrations of Hcy (10, 30, and 100 μM) during 24 h. After the treatment, we analyzed cell viability, morphological parameters, antioxidant defenses, and inflammatory response. Hcy did not induce any alteration in cell viability; however, it was able to induce cytoskeleton rearrangement. The treatment with Hcy also promoted a significant decrease in the activities of Na⁺, K⁺ ATPase, superoxide dismutase (SOD), and glutathione peroxidase (GPx), as well as in the glutathione (GSH) content. Additionally, Hcy induced an increase in the pro-inflammatory cytokine release. In an attempt to elucidate the putative mechanisms involved in the Hcy-induced glial reactivity, we measured the nuclear factor kappa B (NFκB) transcriptional activity and heme oxygenase 1 (HO-1) expression, which were activated and inhibited by Hcy, respectively. In summary, our findings provide important evidences that Hcy modulates critical astrocyte parameters from adult rats, which might be associated to the aging process.

Melatonin's role as a co-adjuvant treatment in colonic diseases: A review

Melatonin is produced in the pineal gland as well as many other organs, including the enterochromaffin cells of the digestive mucosa. Melatonin is a powerful antioxidant that resists oxidative stress due to its capacity to directly scavenge reactive species, to modulate the antioxidant defense system by increasing the activities of antioxidant enzymes, and to stimulate the innate immune response through its direct and indirect actions. In addition, the dysregulation of the circadian system is observed to be related with alterations in colonic motility and cell disruptions due to the modifications of clock genes expression. In the gastrointestinal tract, the activities of melatonin are mediated by melatonin receptors (MT2), serotonin (5-HT), and cholecystokinin B (CCK2) receptors and via receptor-independent processes. The levels of melatonin in the gastrointestinal tract exceed by 10-100 times the blood concentrations. Also, there is an estimated 400 times more melatonin in the gut than in the pineal gland. Gut melatonin secretion is suggested to be influenced by the food intake. Low dose melatonin treatment accelerates intestinal transit time whereas high doses may decrease gut motility. Melatonin has been studied as a co-adjuvant treatment in several gastrointestinal diseases including irritable bowel syndrome (IBS), constipation-predominant IBS (IBS-C), diarrhea-predominant IBS (IBS-D), Crohn's disease, ulcerative colitis, and necrotizing enterocolitis. The purpose of this review is to provide information regarding the potential benefits of melatonin as a co-adjuvant treatment in gastrointestinal diseases, especially IBS, Crohn's disease, ulcerative colitis, and necrotizing enterocolitis.