Homocysteine - from disease biomarker to disease prevention

Development of a chemiluminescent immunoassay based on magnetic solid phase for quantification of homocysteine in human serum

BACKGROUND

Homocysteine (HCY) is a sulfur-containing amino acid that is an independent or important risk factor for the occurrence of many chronic diseases and is one of the most important indicators for determining health risks. However, existing HCY detection methods do not meet the requirements of clinical diagnosis. Therefore, there is an urgent need to establish new detection methods to meet the needs of clinical detection.

RESULTS

In this study, we used the principle of competitive method to establish a new method for the determination of HCY in human serum using a chemiluminescent enzyme immunoassay in conjunction with a chemiluminescent assay instrument that uses magnetic microparticles as the solid phase of the immunoreaction. The established method achieved satisfactory results in terms of minimum detection limit, specificity, accuracy, and clinical application. The limit of detection was 0.03 ng/mL. The intra-assay coefficient of variation (CV) was 1.94-5.05%, the inter-assay CV was 2.29-6.88%, and the recovery rate was 88.60-93.27%. Cross-reactivity with L-cysteine ranged from 0.0100 to 0.0200 μmol/L, and cross-reactivity with glutathione ranged from 0.0100 to 0.200 μmol/L, all of which were less than the limit of detection (LoD) of this method. The linear factor R of this method was greater than 0.99.

CONCLUSIONS

In summary, the developed method showed a good correlation with the product from Abbott. A total of 996 clinical patients with cardiovascular diseases were evaluated using the method developed in this study.

High Homocysteine-Thiolactone Leads to Reduced MENIN Protein Expression and an Impaired DNA Damage Response: Implications for Neural Tube Defects

DNA damage is associated with hyperhomocysteinemia (HHcy) and neural tube defects (NTDs). Additionally, HHcy is a risk factor for NTDs. Therefore, this study examined whether DNA damage is involved in HHcy-induced NTDs and investigated the underlying pathological mechanisms involved. Embryonic day 9 (E9) mouse neuroectoderm cells (NE4C) and homocysteine-thiolactone (HTL, active metabolite of Hcy)-induced NTD chicken embryos were studied by Western blotting, immunofluorescence. RNA interference or gene overexpression techniques were employed to investigate the impact of Menin expression changes on the DNA damage. Chromatin immunoprecipitation-quantitative polymerase chain reaction was used to investigate the epigenetic regulation of histone modifications. An increase in γH2AX (a DNA damage indicator) was detected in HTL-induced NTD chicken embryos and HTL-treated NE4C, accompanied by dysregulation of phospho-Atr-Chk1-nucleotide excision repair (NER) pathway. Further investigation, based on previous research, revealed that disruption of NER was subject to the epigenetic regulation of low-expressed Menin-H3K4me3. Overexpression of Menin or supplementation with folic acid in HTL-treated NE4C reversed the adverse effects caused by high HTL. Additionally, by overexpressing the Mars gene, we tentatively propose a mechanism whereby HTL regulates Menin expression through H3K79hcy, which subsequently influences H3K4me3 modifications, reflecting an interaction between histone modifications. Finally, in 10 human fetal NTDs with HHcy, we detected a decrease in the expression of Menin-H3K4me3 and disorder in the NER pathway, which to some extent validated our proposed mechanism. The present study demonstrated that the decreased expression of Menin in high HTL downregulated H3K4me3 modifications, further weakening the Atr-Chk1-NER pathway, resulting in the occurrence of NTDs.

Elevated homocysteine is associated with increased rates of epigenetic aging in a population with mild cognitive impairment

Elevated plasma total homocysteine (tHcy) is associated with the development of Alzheimer's disease and other forms of dementia. In this study, we report the relationship between tHcy and epigenetic age in older adults with mild cognitive impairment from the VITACOG study. Epigenetic age and rate of aging (ROA) were assessed using various epigenetic clocks, including those developed by Horvath and Hannum, DNAmPhenoAge, and with a focus on Index, a new principal component-based epigenetic clock that, like DNAmPhenoAge, is trained to predict an individual's "PhenoAge." We identified significant associations between tHcy levels and ROA, suggesting that hyperhomocysteinemic individuals were aging at a faster rate. Moreover, Index revealed a normalization of accelerated epigenetic aging in these individuals following treatment with tHcy-lowering B-vitamins. Our results indicate that elevated tHcy is a risk factor for accelerated epigenetic aging, and this can be ameliorated with B-vitamins. These findings have broad relevance for the sizable proportion of the worldwide population with elevated tHcy.

Homocysteine metabolites impair the PHF8/H4K20me1/mTOR/autophagy pathway by upregulating the expression of histone demethylase PHF8-targeting microRNAs in human vascular endothelial cells and mice

The inability to efficiently metabolize homocysteine (Hcy) due to nutritional and genetic deficiencies, leads to hyperhomocysteinemia (HHcy) and endothelial dysfunction, a hallmark of atherosclerosis which underpins cardiovascular disease (CVD). PHF8 is a histone demethylase that demethylates H4K20me1, which affects the mammalian target of rapamycin (mTOR) signaling and autophagy, processes that play important roles in CVD. PHF8 is regulated by microRNA (miR) such as miR-22-3p and miR-1229-3p. Biochemically, HHcy is characterized by elevated levels of Hcy, Hcy-thiolactone and N-Hcy-protein. Here, we examined the effects of these metabolites on miR-22-3p, miR-1229-3p, and their target PHF8, as well as on the downstream consequences of these effects on H4K20me1, mTOR-, and autophagy-related proteins and mRNAs expression in human umbilical vein endothelial cells (HUVEC). We found that treatments with N-Hcy-protein, Hcy-thiolactone, or Hcy upregulated miR-22-3p and miR-1229-3p, attenuated PHF8 expression, upregulated H4K20me1, mTOR, and phospho-mTOR. Autophagy-related proteins (BECN1, ATG5, ATG7, lipidated LC3-II, and LC3-II/LC3-I ratio) were significantly downregulated by at least one of these metabolites. We also found similar changes in the expression of miR-22-3p, Phf8, mTOR- and autophagy-related proteins/mRNAs in vivo in hearts of Cbs-/- mice, which show severe HHcy and endothelial dysfunction. Treatments with inhibitors of miR-22-3p or miR-1229-3p abrogated the effects of Hcy-thiolactone, N-Hcy-protein, and Hcy on miR expression and on PHF8, H4K20me1, mTOR-, and autophagy-related proteins/mRNAs in HUVEC. Taken together, these findings show that Hcy metabolites upregulate miR-22-3p and miR-1229-3p expression, which then dysregulate the PHF8/H4K20me1/mTOR/autophagy pathway, important for vascular homeostasis.

Novel long noncoding lncARF mediated hyperhomocysteinemia-induced atherosclerosis via autophagy inhibition in foam cells

INTRODUCTION

Homocysteine (Hcy) is well recognized to be an independent risk factor for atherosclerosis. Long non-coding RNAs (lncRNAs) are emerging regulators of pathophysiological processes including atherosclerosis, while the underlying mechanisms of its involvement in Hcy induced-atherosclerosis remain largely unknown.

OBJECTIVES

The primary aim of this study is to assess the role of lncARF (autophagy-related factor induced by Hcy) in Hcy induced-atherosclerosis and related mechanism.

METHODS

RNA sequencing of foam cells treated with Hcy revealed a novel specific long noncoding RNA called lncARF. Locked nucleic acid gapmeRs-mediated lncARF knockdown was used to explore the role of lncARF both in vivo and in vitro. Mass spectrometry, RNA pull-down and RNA immunoprecipitation (RIP) assays were employed to uncover a mechanistic role of lncARF. Mass array assay and chromatin immunoprecipitation (ChIP) were used to detect the transcriptional activation of lncARF mediated by transcription factor. Clinically, receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic value of lncARF in atherosclerotic patients with hyperhomocysteinemia (HHcy).

RESULTS

We observed that the expression of lncARF was substantially upregulated in atherosclerotic plaques, and knockdown of lncARF decreased the formation of atherosclerotic lesions by promoting autophagy in foam cells. Mechanistically, lncARF physically binds to RRAGD and inhibits its ubiquitination, further activating the PI3K/Akt and MAPK signaling pathways. Moreover, in vitro experiments showed that transcription factor FosB inhibited the binding of DNMT1 at the lncARF promoter, leading to transcriptional activation through DNA hypomethylation. Clinically, lncARF expression was positively correlated with serum Hcy levels, and it could distinguish atherosclerotic patients with HHcy with a high area under the ROC curve, sensitivity and specificity.

CONCLUSIONS

Our study highlights the mechanisms of lncARF in protecting against the development of atherosclerosis involving the epigenetic modifications and RRAGD/PI3K/Akt and RRAGD/MAPK signaling pathways, which may provide novel diagnostic biomarkers to improve atherosclerosis treatment.

Homocysteine, blood pressure and gene-diet interactions in relation to vascular function measures of black South Africans

BACKGROUND AND AIMS

We investigated circulating homocysteine (Hcy), a cardiovascular disease (CVD) risk factor, examining its dietary associations to provide personalized nutrition advice. This study addressed the inadequacy of current dietary interventions to ultimately address the disproportionately high incidence of CVD in Black populations.

METHODS AND RESULTS

Cross-sectional analyses of 1,867 Black individuals of the PURE-SA study allowed the identification of dietary intake and cardiovascular measure interactions on three sub-categories: (1) normal blood pressure (BP), hypertension or Hcy-related hypertension (H-type), (2) low, normal or high Hcy concentrations, and (3) Hcy-related genetic combinations. Favorable body composition, but adverse dietary intake and cardiovascular determinants, were observed in higher Hcy categories. H-types, compared to regular hypertensives, had higher alcohol and lower macronutrient and micronutrient consumption. Inverse associations with carotid-radial pulse wave velocity were evident between monounsaturated fatty acid (FA) consumption and H-type hypertension as well as polyunsaturated FA and CBS883/ins68 TT carriers. Energy intake was positively associated with vascular cell adhesion molecule-1 (VCAM-1) in variant CBST883C/ins68 and CBS9276 GG carriers. VCAM-1 was also positively associated with plant protein intake in CBS9276 GG and MTR2756 AA carriers and negatively with total protein intake and CBS9276 GG carriers. Alcohol intake was positively associated with intercellular adhesion molecule-1 in MTR2756 minor allele carriers.

CONCLUSION

Because Hcy gene-diet interactions are evident, personalized nutrition, by adjusting diets based on genetic profiles (e.g., CBS and MTR variations) and dietary interactions (e.g., FAs and proteins), can enhance cardiovascular outcomes by managing Hcy and related hypertension in genetically susceptible individuals.

Mitigating Traumatic Brain Injury: A Narrative Review of Supplementation and Dietary Protocols

Traumatic brain injuries (TBIs) constitute a significant public health issue and a major source of disability and death in the United States and worldwide. TBIs are strongly associated with high morbidity and mortality rates, resulting in a host of negative health outcomes and long-term complications and placing a heavy financial burden on healthcare systems. One promising avenue for the prevention and treatment of brain injuries is the design of TBI-specific supplementation and dietary protocols centred around nutraceuticals and biochemical compounds whose mechanisms of action have been shown to interfere with, and potentially alleviate, some of the neurophysiological processes triggered by TBI. For example, evidence suggests that creatine monohydrate and omega-3 fatty acids (DHA and EPA) help decrease inflammation, reduce neural damage and maintain adequate energy supply to the brain following injury. Similarly, melatonin supplementation may improve some of the sleep disturbances often experienced post-TBI. The scope of this narrative review is to summarise the available literature on the neuroprotective effects of selected nutrients in the context of TBI-related outcomes and provide an evidence-based overview of supplementation and dietary protocols that may be considered in individuals affected by-or at high risk for-concussion and more severe head traumas. Prophylactic and/or therapeutic compounds under investigation include creatine monohydrate, omega-3 fatty acids, BCAAs, riboflavin, choline, magnesium, berry anthocyanins, Boswellia serrata, enzogenol, N-Acetylcysteine and melatonin. Results from this analysis are also placed in the context of assessing and addressing important health-related and physiological parameters in the peri-impact period such as premorbid nutrient and metabolic health status, blood glucose regulation and thermoregulation following injury, caffeine consumption and sleep behaviours. As clinical evidence in this research field is rapidly emerging, a comprehensive approach including appropriate nutritional interventions has the potential to mitigate some of the physical, neurological, and emotional damage inflicted by TBIs, promote timely and effective recovery, and inform policymakers in the development of prevention strategies.

Homocysteine Thiolactone Detoxifying Enzymes and Alzheimer's Disease

Elevated levels of homocysteine (Hcy) and related metabolites are associated with Alzheimer's disease (AD). Severe hyperhomocysteinemia causes neurological deficits and worsens behavioral and biochemical traits associated with AD. Although Hcy is precluded from entering the Genetic Code by proofreading mechanisms of aminoacyl-tRNA synthetases, and thus is a non-protein amino acid, it can be attached to proteins via an N-homocysteinylation reaction mediated by Hcy-thiolactone. Because N-homocysteinylation is detrimental to a protein's function and biological integrity, Hcy-thiolactone-detoxifying enzymes-PON1, BLMH, BPHL-have evolved. This narrative review provides an account of the biological function of these enzymes and of the consequences of their impairments, leading to the phenotype characteristic of AD. Overall, accumulating evidence discussed in this review supports a hypothesis that Hcy-thiolactone contributes to neurodegeneration associated with a dysregulated Hcy metabolism.

Is serum homocysteine level a biomarker of suicide attempts: A preliminary study

Suicide is a global public health concern, and understanding its multifaceted determinants is crucial for effective prevention. This study was designed to find an answer to the question of whether serum homocysteine level can be a biomarker of suicide attempts. This preliminary study involving 90 participants (45 suicide attempt cases and 45 controls) was conducted at Elazig Fethi Sekin City Hospital. Biochemical analyses were performed to assess serum homocysteine, vitamin B12, and folic acid levels. Statistical analyses, including t-tests, Mann-Whitney U tests, and ROC analysis, were employed to explore differences between groups and assess the diagnostic potential of homocysteine. Elevated homocysteine levels were found in individuals who attempted suicide compared to the control group (p= <0.001). Additionally, lower levels of vitamin B12 (p=<0.001) and folic acid (p=<0.001) were observed in the suicide attempt group. ROC analysis indicated a significant diagnostic potential for homocysteine in predicting suicide attempts (AUC = 0.845, sensitivity = 91%, specificity = 71%). This study establishes a significant association between high homocysteine levels and suicide attempts, accompanied by lower vitamin B12 and folic acid levels. The findings suggest a potential link between disturbances in homocysteine metabolism and suicidal tendencies, urging further research to establish causation and explore therapeutic implications. Consideration of the study's limitations and directions for future research are warranted.

Increased thyroid stimulating hormone (TSH) as a possible risk factor for atherosclerosis in subclinical hypothyroidism

Primary hypothyroidism (PHT) is associated with an increased risk for the development of atherosclerosis (AS) and other cardiovascular disorders. PHT induces atherosclerosis (AS) through the induction of endothelial dysfunction, and insulin resistance (IR). PHT promotes vasoconstriction and the development of hypertension. However, patients with subclinical PHT with normal thyroid hormones (THs) are also at risk for cardiovascular complications. In subclinical PHT, increasing thyroid stimulating hormone (TSH) levels could be one of the causative factors intricate in the progression of cardiovascular complications including AS. Nevertheless, the mechanistic role of PHT in AS has not been fully clarified in relation to increased TSH. Therefore, in this review, we discuss the association between increased TSH and AS, and how increased TSH may be involved in the pathogenesis of AS. In addition, we also discuss how L-thyroxine treatment affects the development of AS.

Serum S-adenosylhomocysteine levels are associated with first stroke in Chinese adults with hypertension

BACKGROUND

The association between S-adenosylhomocysteine (SAH) and stroke has not been confirmed due to the specialized equipment and time requirements necessary for S-adenosylhomocysteine testing. We aimed to explore the association between SAH and stroke.

METHODS

A nested, case-control study drawn from the China Stroke Primary Prevention Trial of rural adults with hypertension, including 557 first stroke cases and 557 matched controls was conducted. Serum SAH was measured by stable-isotope dilution liquid chromatography-tandem mass spectrometry using 4500MD. Multiple conditional logistic regression models were used to evaluate the association between SAH and first stroke.

RESULTS

In females, SAH levels were significantly higher in the stroke population than in the control group (16.0 ng/mL vs. 14.6 ng/mL). When SAH was assessed as quartiles, the odds of stroke were 1.78 (95 % CI: 1.02-3.09) in Quartile 2, 1.31 (95 % CI: 0.73-2.33) in Quartile 3, and 1.93 (95 % CI: 1.03-3.62) in Quartile 4, compared to Quartile 1. When Quartiles 2-4 were combined, the adjusted odds ratio of first stroke was 1.64 (95 % CI: 1.03-2.62) compared with Quartile 1. In subgroup analysis, a significant SAH-stroke association was observed in the lower vitamin D3 group (OR = 3.35, 95 % CI:1.72-6.53; P interaction, 0.035). In males, higher levels of SAH were associated with an increased risk of stroke in those under age 60. Compared with the reference group, the adjusted odds ratio of total stroke was 2.40 (95 % CI: 1.02-5.91) in the combined group (Quartile 2-4). In contrast, no significant association between SAH and stroke was found in males aged 60 or older.

CONCLUSIONS

This study reveals that SAH is associated with a higher risk of stroke independently of homocysteine, especially in females. SAH may be a second predictor of stroke in the metabolic pathway of methionine, after homocysteine.

Evaluation of anti-seizure medications and their serum concentration with regard to cardiovascular risk parameters: A cross-sectional study

OBJECTIVE

Epilepsy is a chronic disease that requires long-term monitoring and treatment. It is suspected that there is a interaction between the use of anti-seizure medications and the risk of cardiovascular disease. The aim of the study is to investigate the association between the intake of phenobarbital, carbamazepine and valproic acid and their serum drug concentrations (SDC) with various cardiovascular risk parameters (homocysteine, folic acid, vitamin B12, total cholesterol (TC), triglycerides, high- and low-density lipoprotein (LDL)).

METHODS

This is a cross-sectional study. Data (demographic characteristics and laboratory results) of patients treated for epilepsy in a tertiary care hospital between January 2020 and February 2022 were analyzed retrospectively (n = 2014). Kruskal Wallis, Mann-Whitney U, correlation analysis was used, p < 0.05 was considered statistically significant.

RESULTS

The median age of patients was 15 years (IQR:8-31) and 48.3 % were women. The highest homocysteine level was found in patients receiving valproic acid, but it was not statistically significant. Patients receiving phenobarbital had the highest levels of folic acid and B12 and the lowest levels of total cholesterol and low-density lipoprotein cholesterol, which was statistically significant. In patients receiving carbamazepine, a moderately negative significant association was found between serum drug concentration and folic acid levels and a moderately positive significant association was found between TC and LDL levels.

CONCLUSION

In our study, the majority of patients were children and adolescents. Regular monitoring of drug serum concentrations and metabolic parameters may be useful to select the safest drug in terms of cardiovascular disease risk. Randomized controlled trials on the long-term effects of anti-seizure treatment are needed.

Association of vitamin B12, folate, and homocysteine with COVID-19 severity and mortality: A systematic review and meta-analysis

Objective

We aimed to review the available evidence on the association between vitamin B12, folate, and homocysteine levels with worse outcomes among COVID-19 patients.

Methods

The search was carried out in ten databases simultaneously run on 10 May 2023, without language restrictions. We included cross-sectional, case-control, and cohort studies. The random-effects meta-analysis was performed using the Sidik-Jonkman method and corrected 95% confidence intervals using the truncated Knapp-Hartung standard errors. Standardized mean difference and 95% CI was used as the measure effect size.

Results

Thirteen articles were included in this review (n = 2134). Patients with COVID-19 who did not survive had the highest serum vitamin B12 values (SMD: 1.05; 95% CI: 0.31-1.78; p = 0.01, I2 = 91.22%). In contrast, low serum folate values were associated with patients with severe COVID-19 (SMD: -0.77; 95% CI: -1.35 to -0.19; p = 0.02, I2 = 59.09%). The remaining tested differences did not yield significant results.

Conclusion

Elevated serum levels of vitamin B12 were associated with higher mortality in patients with COVID-19. Severe cases of COVID-19 were associated with low serum folate levels. Future studies should incorporate a larger sample size.

Homocysteine thiolactone and other sulfur-containing amino acid metabolites are associated with fibrin clot properties and the risk of ischemic stroke

Homocysteine (Hcy) and Hcy-thiolactone (HTL) affect fibrin clot properties and are linked to cardiovascular disease. Factors that influence fibrin clot properties and stroke are not fully understood. To study sulfur-containing amino acid metabolites, fibrin clot lysis time (CLT) and maximum absorbance (Absmax) in relation to stroke, we analyzed plasma and urine from 191 stroke patients (45.0% women, age 68 ± 12 years) and 291 healthy individuals (59.7% women, age 50 ± 17 years). Plasma and urinary levels of sulfur-containing amino acid metabolites and fibrin clot properties were significantly different in stroke patients compared to healthy individuals. Fibrin CLT correlated with fibrin Absmax in healthy males (R2 = 0.439, P = 0.000), females (R2 = 0.245, P = 0.000), female stroke patients (R2 = 0.187, P = 0.000), but not in male stroke patients (R2 = 0.008, P = ns). Fibrin CLT correlated with age in healthy females but not males while fibrin Absmax correlated with age in both sexes; these correlations were absent in stroke patients. In multiple regression analysis in stroke patients, plasma (p)CysGly, pMet, and MTHFR A1298C polymorphism were associated with fibrin Absmax, while urinary (u)HTL, uCysGly, and pCysGly were significantly associated with fibrin CLT. In healthy individuals, uHTL and uGSH were significantly associated with fibrin Absmax, while pGSH, and CBS T833C 844ins68 polymorphism were associated with fibrin CLT. In logistic regression, uHTL, uHcy, pCysGly, pGSH, MTHFR C677T polymorphism, and Absmax were independently associated with stroke. Our findings suggest that HTL and other sulfur-containing amino acid metabolites influence fibrin clot properties and the risk of stroke.

A comprehensive review and meta-regression analysis of randomized controlled trials examining the impact of vitamin B12 supplementation on homocysteine levels

CONTEXT

Although some research suggests that vitamin B12 (hereafter, B12) supplements can lower homocysteine (Hcy) levels and treat hyperhomocysteinemia, these results are still ambiguous when B12 is taken as an isolated supplement.

OBJECTIVE

This study sought to determine how existing randomized controlled trials (RCTs) could be used to examine the effects of B12 supplementation on Hcy.

DATA SOURCES

To find pertinent RCTs up to June 2022, databases, including PubMed/Medline, Web of Science, Scopus, Cochrane Library, and Embase, were searched.

DATA EXTRACTION

All selected RCTs investigated the impact of B12 supplements on Hcy. A meta-analysis of the eligible studies was performed using the random-effects model.

DATA ANALYSIS

This review included a total of 21 RCTs (N = 1625 participants). Hcy levels were significantly lower after B12 supplementation compared with the control group (pooled weighted mean difference, -4.15 μmol/L; 95% confidence interval, -4.86, -3.45; P < 0.001), and this reduction was even greater with intervention durations ≥12 weeks and doses >500 µg/d. Furthermore, the effect of B12 supplementation in the form of hydroxocobalamin on the reduction of Hcy level was greater compared with other forms.

CONCLUSION

In conclusion, this meta-analysis shows that B12 supplementation has a positive impact on lowering blood Hcy levels, particularly when administered for a longer period and at a larger dose.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022364066.

A label-free and washing-free method to detect biological thiols on a personal glucose meter utilizing glucose oxidase-mimicking activity of gold nanoparticles

We herein developed a label-free and washing-free method to detect biological thiols (biothiols) on a personal glucose meter (PGM) utilizing the intrinsic glucose oxidase (GOx)-mimicking activity of gold nanoparticles (AuNPs). By focusing on the fact that this activity could be diminished by target biothiols through their binding onto the AuNP surface, we correlated the concentration of biothiols with that of glucose readily measurable on a PGM and successfully determined cysteine (Cys), homocysteine (Hcy), and glutathione (GSH) down to 0.116, 0.059, and 0.133 μM, respectively, with high specificity against non-target biomolecules. We further demonstrated its practical applicability by reliably detecting target biothiol in heterogeneous human serum. Due to the meritorious features of PGM such as simplicity, portability, and cost-effectiveness, we believe that this work could serve as a powerful platform for biothiol detection in point-of-care settings.

Exploring research hotspots and future directions in neural tube defects field by bibliometric and bioinformatics analysis

Background

Neural tube defects (NTDs) is the most common birth defect of the central nervous system (CNS) which causes the death of almost 88,000 people every year around the world. Much efforts have been made to investigate the reasons that contribute to NTD and explore new ways to for prevention. We trawl the past decade (2013-2022) published records in order to get a worldwide view about NTDs research field.

Methods

7,437 records about NTDs were retrieved from the Web of Science (WOS) database. Tools such as shell scripts, VOSviewer, SCImago Graphica, CiteSpace and PubTator were used for data analysis and visualization.

Results

Over the past decade, the number of publications has maintained an upward trend, except for 2022. The United States is the country with the highest number of publications and also with the closest collaboration with other countries. Baylor College of Medicine has the closest collaboration with other institutions worldwide and also was the most prolific institution. In the field of NTDs, research focuses on molecular mechanisms such as genes and signaling pathways related to folate metabolism, neurogenic diseases caused by neural tube closure disorders such as myelomeningocele and spina bifida, and prevention and treatment such as folate supplementation and surgical procedures. Most NTDs related genes are related to development, cell projection parts, and molecular binding. These genes are mainly concentrated in cancer, Wnt, MAPK, PI3K-Akt and other signaling pathways. The distribution of NTDs related SNPs on chromosomes 1, 3, 5, 11, 14, and 17 are relatively concentrated, which may be associated with high-risk of NTDs.

Conclusion

Bibliometric analysis of the literature on NTDs field provided the current status, hotspots and future directions to some extant. Further bioinformatics analysis expanded our understanding of NTDs-related genes function and revealed some important SNP clusters and loci. This study provided some guidance for further studies. More extensive cooperation and further research are needed to overcome the ongoing challenge in pathogenesis, prevention and treatment of NTDs.

A micronutrient supplement modulates homocysteine levels regardless of vitamin B biostatus in elderly subjects

Elevated homocysteine (Hcy) levels (≥15 μmol/L) in the elderly are frequently associated with a higher risk of cardiovascular disease and cognitive decline. Several studies have already shown an Hcy-lowering effect of B vitamin supplementation in cohorts deficient in these nutrients. The aim of this randomized, double-blinded 12-week intervention study was to investigate whether Hcy levels in healthy elderly subjects (75.4±4.5 years, n=133) could be lowered with a micronutrient supplement (i.e., 400 μg folic acid, 100 μg cobalamin). Difference in mean initial Hcy levels between intervention (17.6±7.1 μmol/L, n=65) and placebo group (18.9±6.1 μmol/L, n=68) was not significant. The prevalence of cobalamin and folate deficiency in the total study population was low: 27% had serum-cobalamin levels ≤150 pmol/L, 12% holo-transcobalamin (Holo-TC) levels ≤50 pmol/L, 13% low cobalamin status using the aggregated cobalamin marker 4cB12 and 10% red blood cell (RBC) folate ≤570 nmol/L. Nevertheless, the treated subjects still showed improved cobalamin and folate biostatus (serum cobalamin Δt12-t0: 63±48 pmol/L; Holo-TC Δt12-t0: 17±19 pmol/L; RBC folate Δt12-t0: 326±253 nmol/L) and Hcy levels (Δt12-t0: -3.6±5.7 μmol/L). The effects were statistically significant compared to the placebo group with p=0.005 (serum cobalamin), p=0.021 (Holo-TC), p=0.014 (RBC-folate) and p<0.001 (Hcy). The Hcy-lowering effect was dependent on the initial Hcy levels (p<0.001). Our findings suggest that elevated Hcy levels in elderly subjects can be lowered regardless of the initial cobalamin and folate biostatus.

Plasma levels of hydrogen sulfide and homocysteine correlate with the efficacy of antidepressant agents and serve as potential diagnostic and therapeutic markers

OBJECTIVE

Hydrogen sulfide (H2S) is associated with depressive-like behavior in rodents. We undertook cross-sectional and longitudinal analyses of plasma levels of H2S and its substrate homocysteine (Hcy) in depression and assessed the association of both parameters with psychopathology and cognitive function.

METHODS

Forty-one patients suffering from depression (PSDs) and 48 healthy volunteers were recruited. PSDs were treated for 8 weeks. Analyzable data were collected from all participants for assessment of their psychopathology and cognitive function. Plasma was collected for determination of levels of H2S and Hcy, and data were correlated to determine their potential as plasma biomarkers.

RESULTS

Cross-sectional analyses revealed PSDs to have a low plasma H2S level and high Hcy level. Longitudinal analyses revealed that 8 weeks of treatment reversed the changes in plasma levels of H2S and Hcy in PSDs. Plasma levels of H2S and Hcy were associated with psychopathology and cognitive function in depression. The area under the receiver operating characteristic curve (AUC) for a combination of plasma levels of H2S and Hcy and expression of the TNF gene (i.e., H2S-Hcy-TNF) was 0.848 for diagnosing depression and 0.977 for predicting the efficacy of antidepressant agents.

CONCLUSION

Plasma levels of H2S and Hcy reflect changes in psychopathology and cognitive function in depression and H2S-Hcy-TNF has the potential to diagnose depression and predict the efficacy of antidepressant medications.

Dosage exploration of combined B-vitamin supplementation in stroke prevention: a meta-analysis and systematic review

BACKGROUND

The optimal dosage range for B-vitamin supplementation for stroke prevention has not received sufficient attention.

OBJECTIVE

Our aim was to determine the optimal dosage range of a combination of folic acid, vitamin B12, and vitamin B6 supplementation in stroke prevention.

METHODS

We searched PubMed, the Cochrane Central Register of Controlled Trials, and Embase database for randomized controlled trials published between January 1966 and April 2023, whose participants received B-vitamin supplementation and that reported the number of stroke cases. Relative risk (RR) was used to measure the effect of combined supplementation on risk of stroke using a fixed-effects model. Risk of bias was assessed with the Cochrane risk-of-bias algorithm.

RESULTS

The search identified 14 randomized controlled trials of folic acid combined with vitamin B12 and vitamin B6 supplementation for stroke prevention that included 76,664 participants with 2720 stroke cases. In areas without and with partial folic acid fortification, combined B-vitamin supplementation significantly reduced the risk of stroke by 34% [RR: 0.66; 95% confidence interval (CI): 0.50, 0.86] and 11% (RR: 0.89; 95% CI: 0.79, 1.00), respectively. Further analysis showed that a dosage of folic acid ≤0.8 mg/d and vitamin B12 ≤0.4 mg/d was best for stroke prevention (RR: 0.65; 95% CI: 0.48, 0.86) in these areas. In contrast, no benefit of combined supplementation was found in fortified areas (RR: 1.04; 95% CI: 0.94, 1.16).

CONCLUSIONS

Our meta-analysis found that the folic acid combined with vitamin B12 and vitamin B6 supplementation strategy significantly reduced the risk of stroke in areas without and with partial folic acid fortification. Combined dosages not exceeding 0.8 mg/d for folic acid and 0.4 mg/d for vitamin B12 supplementation may be more effective for populations within these areas. This trial was registered at PROSPERO asCRD42022355077.

Association of Increased Homocysteine Levels with Impaired Folate Metabolism and Vitamin B Deficiency in Early-Onset Multiple Sclerosis

The contents of homocysteine (HCy), cyanocobalamin (vitamin B12), folic acid (vitamin B9), and pyridoxine (vitamin B6) were analyzed and the genotypes of the main gene polymorphisms associated with folate metabolism (C677T and A1298C of the MTHFR gene, A2756G of the MTR gene and A66G of the MTRR gene) were determined in children at the onset of multiple sclerosis (MS) (with disease duration of no more than six months), healthy children under 18 years (control group), healthy adults without neurological pathology, adult patients with MS at the onset of disease, and adult patients with long-term MS. A significant increase in the HCy levels was found in children at the MS onset compared to healthy children of the corresponding age. It was established that the content of HCy in children has a high predictive value. At the same time, an increase in the HCy levels was not accompanied by the deficiency of vitamins B6, B9, and B12 in the blood. The lack of correlation between the laboratory signs of vitamin deficiency and HCy levels may be due to the polymorphic variants of folate cycle genes. An increased HCy level should be considered as a marker of functional disorders of folate metabolism accompanying the development of pathological process in pediatric MS. Our finding can be used to develop new approaches to the prevention of demyelination in children and treatment of pediatric MS.

Association between dietary folate intake and severe headache among adults in the USA: a cross-sectional survey

Folate, also known as vitamin B9, is a water-soluble vitamin. Previous studies on dietary folate intake in severe headache patients were equivocal. Therefore, we conducted a cross-sectional study to elucidate the relationship between folate intake and severe headache. This cross-sectional study used data from participants over 20 years old who participated in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2004. The diagnosis of severe headache was made through participants' self-report in the NHANES questionnaire section. We performed multivariate logistic regression and restricted cubic spline (RCS) regression to explore the relationship between folate intake and severe headache. A total of 9859 participants took part in the study, 1965 of whom were severe headache patients and the rest were non-severe headache. We found that dietary folate intake was significantly and inversely associated with severe headache. Compared with participants with lower folate intake Q1 (≤ 229·97 ug/d), the adjusted OR values for dietary folate intake and severe headache in Q2 (229·98-337 ug/d), Q3 (337·01-485 ug/d) and Q4 (≥ 485·01 ug/d) were 0·81 (95 % CI: 0·67, 0·98, P = 0·03), 0·93 (95 % CI: 0·77, 1·12, P = 0·41) and 0·63 (95 % CI: 0·49, 0·80, P < 0·001), respectively. For women aged 20-50 years, there was a non-linear association between folate intake and severe headache in the RCS. Women aged 20-50 years should have higher awareness of dietary folate and increase their dietary intake of folate, which may aid in preventing severe headache.

Linking biomarkers with healthy lifestyle outcomes after stroke: Supplementary results of a 12-month randomized controlled trial

BACKGROUND AND AIMS

Participation in a healthy lifestyle intervention such as the Diabetes Prevention Program Group Lifestyle Balance-adapted for stroke (GLB-CVA) may reduce stroke burden. Identifying biomarkers associated with lifestyle changes may enhance an individualized approach to stroke recovery. We investigated metabolic biomarkers related to cardiovascular and neurological function in individuals with stroke in the GLB-CVA study and healthy (non-stroke) individuals.

METHODS AND RESULTS

Participants with chronic (>12 months) stroke were recruited to this wait-list randomized controlled trial if they were overweight (BMI ≥25 kg/m2). Participants were randomized to (1) the GLB-CVA program to complete 22 educational sessions addressing behavioral principals of dietary and physical activity or (2) a 6 month wait-list control (WLC). Biomarkers [Plasma irisin, vascular endothelial growth factor, lipoprotein-associated phospholipase A2 (Lp-PLA2), insulin-like growth factor 1 and brain-derived neurotrophic factor (BDNF)] were collected at baseline, 3, and 6 months. Age-matched healthy individuals were recruited for biomarker assessment. Compared to healthy adults (n = 19), participants with stroke (GLB-CVA = 24; WLC = 24) at baseline had higher tHcy levels (p < 0.001) and lower PLA2 levels (p = 0.016). No statistically significant interactions were observed for any biomarkers between the GLB-CVA and WLC or between people who achieved 5% weight loss and those who did not.

CONCLUSION

Participation in a 6-month healthy lifestyle program did not result in statistically significant changes to select metabolic biomarker levels for our participants with chronic stroke. However, participants with stroke demonstrated a unique biomarker profile compared to age-matched healthy individuals.

Oxidative stress in acute pulmonary embolism: emerging roles and therapeutic implications

Oxidative stress is an imbalance between the body's reactive oxygen species and antioxidant defense mechanisms. Oxidative stress is involved in the development of several cardiovascular diseases, such as pulmonary hypertension, atherosclerosis, and diabetes mellitus. A growing number of studies have suggested the potential role of oxidative stress in the pathogenesis of pulmonary embolism. Biomarkers of oxidative stress in pulmonary embolism have also been explored, such as matrix metalloproteinases, asymmetric dimethylarginine, and neutrophil/lymphocyte ratio. Here, we comprehensively summarize some oxidative stress mechanisms and biomarkers in the development of acute pulmonary embolism and summarize related treatments based on antioxidant stress to explore effective treatment strategies for acute pulmonary embolism.

Relationships of B12 and Homocysteine with Outcomes in the SURE-PD, SURE-PD3, and STEADY-PDIII Trials

Background

DATATOP was a study of early Parkinson's disease (PD) conducted in the 1980 s, before mandatory folic acid fortification in the United States. Our analysis of its baseline serum samples revealed a geometric mean vitamin B12 of 369 pg/mL and homocysteine (tHcy) of 9.5μmol/l. We also found that low B12 predicted greater worsening of ambulatory capacity (AC) and elevated tHcy (>15μmol/L) predicted greater declines in cognitive function.

Objective

We sought to measure B12 and tHcy in contemporary trial participants with early PD who had not started dopaminergic treatment and to determine whether these analytes were associated with clinical progression.

Methods

We measured B12 and tHcy from baseline and end-of-study blood samples from three recent clinical trials.

Results

Baseline geometric mean B12 levels for these studies ranged from 484- 618 pg/ml and for tHcy ranged from 7.4- 10μmol/L. Use of B12-containing supplements ranged from 41- 61%, and those taking supplements had higher B12 and lower tHcy. Those who began levodopa, but were not taking B12-supplements, had greater end-of-study tHcy. There was no association of baseline tHcy > 15μmol/L with annualized change in Montreal Cognitive Assessment and no association of baseline B12 tertiles with change in AC.

Conclusions

In these longitudinal trials, B12 levels were higher than for DATATOP, due in large part to increased B12-supplement intake, while tHcy levels were similar. Initiation of levodopa was associated with increases of tHcy in those not taking a B12-containing supplement. These smaller studies did not replicate prior findings of low B12 and elevated tHcy with features of progression, possibly due to higher baseline B12.

Deciphering prognostic indicators in AQP4-IgG-seropositive neuromyelitis optica spectrum disorder: An integrative review of demographic and laboratory factors

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a group of inflammatory diseases affecting the central nervous system, characterized by optic neuritis and myelitis. The complex nature of NMOSD and varied patient response necessitates personalized treatment and efficient patient stratification strategies.

OBJECTIVE

To provide a comprehensive review of recent advances in clinical and biomarker research related to aquaporin-4 (AQP4)-immunoglobulin G (IgG)-seropositive NMOSD prognosis and identify key areas for future research.

METHODS

A comprehensive review and synthesis of recent literature were conducted, focusing on demographic factors and laboratory investigations.

RESULTS

Demographic factors, such as age, ethnicity, and sex, influence NMOSD prognosis. Key biomarkers for NMOSD prognosis include homocysteine, antinuclear antibodies, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, thyroid hormone levels, neurofilament light chain levels, and serum glial fibrillary acidic protein might also predict NMOSD attack prognosis.

CONCLUSION

Further investigation is required to understand sex-related disparities and biomarker inconsistencies. Identification and understanding of these factors can aid in the development of personalized therapeutic strategies, thereby improving outcomes for NMOSD patients. Future studies should focus on unifying research design for consistent results.

Blood Homocysteine Levels Mediate the Association Between Blood Lead Levels and Cardiovascular Mortality

Lead is a heavy, toxic metal and its exposure to humans can lead to increased risk of cardiovascular disease development and mortality. Lead exposure has been shown to induce hyperhomocysteinemia (HHCy) which may be a major pathogenic risk for the risk of CVDs. The aim of this study was to investigate whether homocysteine (Hcy) mediates the effect of lead on cardiovascular mortality. A total of 17,915 adults aged ≥ 20 who participated in the National Health and Nutrition Examination Survey (1999 to 2006). Information on mortality was ascertained via probabilistic matching to the death certificates from the National Death Index recorded up to December 31, 2015. Cox proportional hazards regression was performed to assess the association between blood lead levels and mortality. Mediation via Hcy was examined using a logit model. During a mean follow-up of 11.6 years, the incidences of CVD mortality were 0.73, 2.18, 3.03 and 4.94 per 1000 person-years across quarterlies of blood lead levels from low to high. Following multivariable adjustment, blood lead levels were strongly associated with CVD mortality in all mortality models (p-trend < 0.001). This association remained statistically significant after further adjusting for quartiles of homocysteine (model 3; HR 1.38 (95% CI 1.01-1.89) p-trend < 0.001). Furthermore, blood lead levels increased the odds of CVD mortality via homocysteine (indirect effect) (OR 1.42 (95% CI 1.30-1.55)), demonstrating the mediatory effect of homocysteine. This the first study that demonstrates that increased homocysteine mediates nearly half of CVD mortality related to blood lead levels.

The Role of Diet in Parkinson's Disease

The aim of this review is to examine the intersection of Parkinson's disease (PD) with nutrition, to identify best nutritional practices based on current evidence, and to identify gaps in the evidence and suggest future directions. Epidemiological work has linked various dietary patterns and food groups to changes in PD risk; however, fewer studies have evaluated the role of various diets, dietary components, and supplements in the management of established PD. There is substantial interest in exploring the role of diet-related interventions in both symptomatic management and potential disease modification. In this paper, we evaluate the utility of several dietary patterns, including the Mediterranean (MeDi), Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND), Alternative Healthy Eating Index (AHEI), vegan/vegetarian, and ketogenic diet in persons with PD. Additionally, we provide an overview of the evidence relating several individual food groups and nutritional supplements to PD risk, symptoms and progression.

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.

Association analysis of MTHFR (rs1801133 and rs1801131) and MTRR (rs1801394) gene polymorphisms towards the development of hypertension in the Bai population from Yunnan, China

OBJECTIVE

Hypertension is one of the leading causes of human death and disability. MTHFR and MTRR regulate folate metabolism and are closely linked to hypertension, although the relationship is inconsistent among different ethnic groups. The present study aims to investigate the effects of MTHFR C677T (rs1801133), MTHFR A1298C (rs1801131), and MTRR A66G (rs1801394) polymorphisms on hypertension susceptibility in the Bai nationality of the Yunnan Province, China.

METHODS

This case-control study included 373 hypertensive patients and 240 healthy controls from the Chinese Bai population. The genotyping of MTHFR and MTRR gene polymorphisms was carried out by using the KASP method. The effects of genetic variations of MTHFR and MTRR genes on hypertension risk were evaluated with odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS

The present study revealed that the CT and TT genotypes and T allele of MTHFR C677T locus were considerably associated with an increased risk of hypertension. In addition, MTHFR A1298C locus CC genotype could significantly increase the hypertension risk. The T-A and C-C haplotypes of MTHFR C677T and MTHFR A1298C could increase the risk of hypertension. Further stratified analysis by risk rank of folate metabolism indicated that people with poor utilization of folic acid were more prone to develop hypertension. In the hypertension group, the MTHFR C677T polymorphism was significantly associated with fasting blood glucose, fructosamine, apolipoprotein A1, homocysteine, superoxide dismutase, and malondialdehyde levels.

CONCLUSION

Our study suggested that genetic variations of MTHFR C677T and MTHFR A1298C were significantly associated with susceptibility to hypertension in the Bai population from Yunnan, China.

Folate - a scoping review for Nordic Nutrition Recommendations 2023

Folate is an essential micronutrient for normal development and metabolic function, and folate deficiency is associated with an increased risk of cancer, cardiovascular disease, mental dysfuntion and negative pregnancy outcomes. When estimating folate requirements, one must consider different bioavailability and functionality between synthetic folic acid and dietary folate, together with increased needs of folate in women of fertile age, pregnant and lactating women, preterm and small for gestational age weight infants and individuals who are homozygote for the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene polymorphism. In order to achieve an adequate metabolic status based on the metabolic marker total homocysteine, and not merely the absence of clinical signs of folate deficiency, the recommended intake of folate differs according to age, pregnancy and lactation. According to the World Health Organization, a decision limit for folate deficiency in adults is serum folate level below 10 nmol/L, and in women of fertile age a red blood cell folate level below 906 nmol/L in order to prevent neural tube defects. Qualified systematic reviews along with identified relevant literature have been used for this scoping review prepared for the Nordic Nutrition Recommendations 2023.

Late-onset cobalamin C deficiency type in adult with cognitive and behavioral disturbances and significant cortical atrophy and cerebellar damage in the MRI: a case report

Background

Late-onset cobalamin C (cblC) deficiency is associated with a wide range of neurological and psychiatric symptoms, hematological manifestations, anorexia, renal failure, ocular abnormalities, dermatitis, and pancreatitis. However, the neuroimaging characteristics of late-onset cblC deficiency remain insufficiently documented. Common findings include diffuse white matter swelling, varying degrees of severe leukoaraiosis, hydrocephalus, corpus callosum atrophy, and symmetric bilateral basal ganglia lesions. In this report, we present a case of late-onset cblC deficiency in adults presenting with cerebellar ataxia as the primary symptom. The MRI findings revealed bilateral lateral cerebellar hemispheres exhibiting symmetric hyperintensity, primarily observed in diffusion-weighted imaging (DWI), which is a rarely reported imaging change in this context.

Case presentation

Our patient was a male who experienced symptoms starting at the age of 30 years, including unsteady walking, apparent cerebellar ataxia, and cognitive impairment upon nervous system examination. Brain magnetic resonance imaging (MRI) exhibited symmetric hyperintensity in the bilateral lateral cerebellar hemispheres, predominantly manifested in DWI, without any enhancement. Subsequently, significantly elevated blood total homocysteine and urinary methylmalonic acid levels were observed. Genetic analysis confirmed the presence of MMACHC compound heterozygous mutants c.482G > A and c.609G > A, thus confirming the diagnosis of cblC deficiency. These variants were classified as likely pathogenic following the guidelines of the American College of Medical Genetics and Genomics (ACMG) and were verified using Sanger sequencing. Following treatment, the patient experienced improvements in walking ability and cognition, a significant decrease in blood total homocysteine levels, and reversal of the imaging lesions.

In conclusion

Late-onset cblC deficiency presents with diverse clinical and imaging manifestations. Early diagnosis and treatment are crucial in achieving a favorable prognosis. This case serves as a reminder to clinicians not to overlook genetic metabolic disorders, particularly those causing multisite damage, in adult patients with undiagnosed neurological disorders, especially those affecting the cerebellum. Notably, methylmalonic acidemia should be considered within the spectrum of bilateral cerebellar lesions.

The effects of folinic acid and l-methylfolate supplementation on serum total homocysteine levels in healthy adults

BACKGROUND - AIM

Hyperhomocysteinemia is recognized as a risk factor for several diseases and conditions. The aim of this study was to investigate and compare the efficacy of two total homocysteine (tHcy)-lowering treatments including folinic acid or l-methylfolate in healthy Greek adults.

METHODS

Two hundred and seventy-two healthy Greek adults (143 men, 129 women; mean age±SD: 43.0 ± 15.3 years), with serum tHcy levels ≥10 μmol/L received randomized folinic acid ("Folinic acid Group") or l-methylfolate ("l-methylfolate Group") orally for three months. All subjects with serum cobalamin (Cbl) levels <300 pg/mL additionally received 1 mg hydroxycobalamine intramuscularly twice a week for the first month only. Serum folate, Cbl and tHcy levels were determined using immunoassays methods at the beginning and the end of the study period. The MTHFR C677T and MTHFR A1298C gene polymorphisms were genotyped using polymerase chain reaction and reverse hybridization.

RESULTS

At the end of the 3-month intervention period, the levels of serum folate and Cbl increased significantly, whereas the levels of serum tHcy decreased significantly in the two groups. The individuals with MTHFR 677TT genotype had a significantly higher reduction in serum tHcy levels than the individuals with the MTHFR 677CC or MTHFR 677CT genotypes. Although the "Folinic acid Group" had a considerably higher increase in their serum folate levels (but not Cbl) than the "l-methylfolate Group", the reduction of serum tHcy levels between the two groups was not substantially different. The individuals with MTHFR 677CT genotype had a statistically significant higher reduction in serum tHcy levels when supplemented with folinic acid rather than l-methylfolate.

CONCLUSIONS

The administration of folinic acid compared to l-methylfolate caused a higher increase of serum folate levels but no difference in the reduction of serum tHcy levels. The reduction of serum tHcy levels was influenced by the existence of MTHFR C677T and not MTHFR A1298C gene polymorphisms. The individuals with MTHFR 677CT genotype appear to benefit more by folinic acid than l-methylfolate supplementation.

Integrated analysis of the association between methionine cycle and risk of moyamoya disease

OBJECTIVE

The role of methionine (Met) cycle in the pathogenesis and progression of cardiovascular and cerebrovascular diseases has been established, but its association with moyamoya disease (MMD) has rarely been studied. This study aimed to analyze the levels of Met cycle-related metabolites and constructed a risk model to explore its association with the risk of MMD.

METHODS

In this prospective study, a total of 302 adult MMD patients and 88 age-matched healthy individuals were consecutively recruited. The serum levels of Met cycle-related metabolites were quantified by liquid chromatography-mass spectrometry (LC-MS). Participants were randomly divided into training set and testing set at a ratio of 1:1. The training set was used to construct the risk score model by LASSO regression. The association between Met cycle-related risk score and the risk of MMD was analyzed using logistic regression and assessed by ROC curves. The testing set was used for validation.

RESULTS

The levels of methionine sulfoxide and homocysteine were significantly increased, while the levels of betaine and choline were significantly decreased in MMD and its subtypes compared to healthy controls (p < 0.05 for all). The training set was used to construct the risk model and the risk score of each participant has been calculated. After adjusting for potential confounders, the risk score was independently associated with the risk of MMD and its subtypes (p < 0.05 for all). We then divided the participants into low-risk and high-risk groups, the high-risk score was significantly associated with the risk of MMD and its subtypes (p < 0.05 for all). The risk scores were further assessed as tertiles, the highest tertile was significantly associated with a higher risk of MMD and its subtypes compared to the lowest (p < 0.05 for all). The results were validated in the testing set.

CONCLUSION

This study has constructed and validated a risk model based on Met cycle-related metabolites, which was independently associated with the risk of MMD and its subtypes. The findings provided a new perspective on the risk evaluation and prevention of MMD.

Homocysteine metabolites inhibit autophagy, elevate amyloid beta, and induce neuropathy by impairing Phf8/H4K20me1-dependent epigenetic regulation of mTOR in cystathionine β-synthase-deficient mice

The loss of cystathionine β-synthase (CBS), an important homocysteine (Hcy)-metabolizing enzyme or the loss of PHF8, an important histone demethylase participating in epigenetic regulation, causes severe intellectual disability in humans. Similar neuropathies were also observed in Cbs-/- and Phf8-/- mice. How CBS or PHF8 depletion can cause neuropathy was unknown. To answer this question, we examined a possible interaction between PHF8 and CBS using Cbs-/- mouse and neuroblastoma cell models. We quantified gene expression by RT-qPCR and western blotting, mTOR-bound H4K20me1 by chromatin immunoprecipitation (CHIP) assay, and amyloid β (Aβ) by confocal fluorescence microscopy using anti-Aβ antibody. We found significantly reduced expression of Phf8, increased H4K20me1, increased mTOR expression and phosphorylation, and increased App, both on protein and mRNA levels in brains of Cbs-/- mice versus Cbs+/- sibling controls. Autophagy-related Becn1, Atg5, and Atg7 were downregulated while p62, Nfl, and Gfap were upregulated on protein and mRNA levels, suggesting reduced autophagy and increased neurodegeneration in Cbs-/- brains. In mouse neuroblastoma N2a or N2a-APPswe cells, treatments with Hcy-thiolactone, N-Hcy-protein or Hcy, or Cbs gene silencing by RNA interference significantly reduced Phf8 expression and increased total H4K20me1 as well as mTOR promoter-bound H4K20me1. This led to transcriptional mTOR upregulation, autophagy downregulation, and significantly increased APP and Aβ levels. The Phf8 gene silencing increased Aβ, but not APP, levels. Taken together, our findings identify Phf8 as a regulator of Aβ synthesis and suggest that neuropathy of Cbs deficiency is mediated by Hcy metabolites, which transcriptionally dysregulate the Phf8 → H4K20me1 → mTOR → autophagy pathway thereby increasing Aβ accumulation.

The role of PIMT in Alzheimer's disease pathogenesis: A novel hypothesis

There are multiple theories of Alzheimer's disease pathogenesis. One major theory is that oxidation of amyloid beta (Aβ) promotes plaque deposition that directly contributes to pathology. A competing theory is that hypomethylation of DNA (due to altered one carbon metabolism) results in pathology through altered gene regulation. Herein, we propose a novel hypothesis involving L-isoaspartyl methyltransferase (PIMT) that unifies the Aβ and DNA hypomethylation hypotheses into a single model. Importantly, the proposed model allows bidirectional regulation of Aβ oxidation and DNA hypomethylation. The proposed hypothesis does not exclude simultaneous contributions by other mechanisms (e.g., neurofibrillary tangles). The new hypothesis is formulated to encompass oxidative stress, fibrillation, DNA hypomethylation, and metabolic perturbations in one carbon metabolism (i.e., methionine and folate cycles). In addition, deductive predictions of the hypothesis are presented both to guide empirical testing of the hypothesis and to provide candidate strategies for therapeutic intervention and/or nutritional modification. HIGHLIGHTS: PIMT repairs L-isoaspartyl groups on amyloid beta and decreases fibrillation. SAM is a common methyl donor for PIMT and DNA methyltransferases. Increased PIMT activity competes with DNA methylation and vice versa. The PIMT hypothesis bridges a gap between plaque and DNA methylation hypotheses.

Risk factors for cognitive dysfunction and glycemic management in older adults with type 2 diabetes mellitus: a retrospective study

BACKGROUND

Epidemiological evidence shows a robust relationship between cognitive dysfunction and type 2 diabetes mellitus (T2DM). This study identified major risk factors that might prevent or ameliorate T2DM-associated cognitive dysfunction in the realm of clinical practice.

METHODS

Using Mini-mental State Examination (MMSE) in the light of education level, we identified older adults with T2DM on admission aged 50 and above. We conducted this case-control study when eligible participants were divided into Cognitively Normal (CN) group and Cognitively Impaired (CI) group. Analytical data referred to demographic characteristics, clinical features, fluid biomarkers, and scale tests.

RESULTS

Of 596 records screened, 504 cases were included in the final analysis. Modified multivariate logistic regression analysis verified that homocysteine (OR = 2.048, 95%CI = 1.129-3.713), brain infarction (OR = 1.963, 95%CI = 1.197-3.218), dementia (OR = 9.430, 95%CI = 2.113-42.093), education level (OR = 0.605, 95%CI = 0.367-0.997), severity of dependence (OR = 1.996, 95%CI = 1.397-2.851), creatine kinase (OR = 0.514, 95%CI = 0.271-0.974) were significant risk factors of incident T2DM-related cognitive dysfunction in patients of advanced age.

CONCLUSION

Our study supported a robust relationship between T2DM and cognitive dysfunction. Our results provide clinicians with major risk factors for T2DM-related cognitive dysfunction, in particular the protective role of creatine kinase.

Homocysteine Reduction for Stroke Prevention: Regarding the Recent AHA/ASA 2021 Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack

Reduction of secondary ischemic stroke risk following an initial stroke is an important goal. The 2021 Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack assembles opportunities for up to 80% secondary stroke reduction. Homocysteine reduction was not included in the recommendations. The reduction of homocysteine with low doses of folic acid has been shown to reduce ischemic stroke and all stroke. This has been obscured by studies using high doses of folic acid and cyanocobalamin in patients with renal failure and Methylenetetrahydrofolate reductase (MTHFR) polymorphisms. The confounding impacts of high dose folic acid and cyanocobalamin toxicity in renal failure and MTHFR C677T subgroups are discussed. New studies show that their toxicity is due to non-bioequivalence to the natural dietary forms, L-methylfolate and methylcobalamin. Low doses of folic acid and cyanocobalamin are safer than high doses for these subpopulations. Even lower toxicity with greater effectiveness for reducing homocysteine is seen with L-methylfolate and methylcobalamin, which are safe at high doses. Retinal vascular imaging is a noninvasive method for evaluating central nervous system (CNS) microangiopathy. A formulation containing l-methylfolate and methylcobalamin has been shown to reduce homocysteine and increase perfusion in diabetic retinopathy. This supports homocysteine intervention for CNS ischemia. Future ischemic stroke intervention studies could benefit from monitoring retinal perfusion to estimate the impact of risk reduction strategies. The omission of a recommendation for homocysteine and secondary stroke reduction through the use of B vitamins should be reconsidered in light of re-analysis of major B vitamin intervention studies and new technologies for monitoring CNS perfusion. We recommend revision of the 2021 Guideline to include homocysteine reduction with low doses of folic acid and cyanocobalamin, or better yet, L-methylfolate and methylcobalamin, making a good clinical guideline better.

Characteristics, differential diagnosis, individualized treatment, and prevention of hyperhomocysteinemia in newborns

OBJECTIVES

This study aimed to investigate the incidence rate, clinical phenotype, gene variation spectrum, and prognosis of neonatal hyperhomocysteinemia (HHcy) and explore its diagnosis, individualised treatment, and prevention strategies.

METHODS

We screened 84722 neonates for HHcy using liquid chromatography-tandem mass spectrometry (LC-MS/MS) combined with biochemical detection, urine gas chromatography-mass spectrometry (GC-MS), and next-generation sequencing (NGS) for gene analysis to comprehensively differentiate and diagnose diseases.

RESULTS

18 children (P1-P18) were diagnosed with methylmalonic acidemia (MMA) and HHcy, and fourteen known and one new variant of the MMACHC gene were found. Five children showed poor mental reactions, brain dysplasia, lethargy, hyperbilirubinemia, and jaundice, whereas the other 13 children had no evident abnormalities. These children were all cobalamin- and folic acid-reactive types, and they were mainly supplemented with cobalamin, L-carnitine, betaine, and folic acid. The mother of P12 had a prenatal diagnosis at the next pregnancy; the results showed that MMACHC gene was not pathogenic and she gave birth to a healthy baby. One child (P19) was diagnosed with methylenetetrahydrofolate reductase (MTHFR) deficiency, and one new mutation was detected in the MTHFR gene. Patient P19 showed congenital brain dysplasia, neonatal anaemia, and hyperbilirubinemia, and treatment consisted mainly of betaine and cobalamin supplementation. One child (P20) was confirmed to have methionine adenosyltransferase I (MAT I) deficiency but had no clinical manifestations. After treatment, all the children had a good prognosis.

CONCLUSION

The incidence of neonatal HHcy in the Zibo area was 1/4236, and the common pathogenic variants were c.609G>A, c.80A>G, and c.482G>A in the MMACHC gene. Patients with HHcy can achieve a good prognosis if pathogenic factors and targeted treatment are identified. Gene analysis and prenatal diagnosis contribute to the early prevention of HHcy.

Association of Long-term Exposure to Air Pollution and Dementia Risk: The Role of Homocysteine, Methionine, and Cardiovascular Burden

BACKGROUND AND OBJECTIVES

Growing evidence links air pollution with dementia risk, but the biological mechanisms are largely unknown. We investigated the role played by homocysteine (tHcy) and methionine in this association and explored whether this could be explained by cardiovascular diseases (CVDs).

METHODS

Data were extracted from the ongoing Swedish National study on Aging and Care in Kungsholmen (SNAC-K), a longitudinal population-based study. At baseline, 2,512 dementia-free participants were examined up to 2013 (mean follow-up: 5.18 ± 2.96 years). Two air pollutants (particulate matter ≤2.5 μm [PM2.5] and nitrogen oxides [NOx]) were assessed yearly from 1990 until 2013 using dispersion models at residential addresses. The hazard ratio of dementia over air pollution levels was estimated using Cox models adjusted for age, sex, education, smoking, socioeconomic status, physical activity, retirement age, creatinine, year of assessment, and the use of supplements. The total effect of air pollutants on dementia was decomposed into 4 pathways involving tHcy/methionine: (1) direct effect; (2) indirect effect (mediation); (3) effect due to interaction; and (4) effect due to both mediation and interaction. To test whether the association was independent from CVDs (ischemic heart disease, atrial fibrillation, heart failure, and stroke), we repeated the analyses excluding those individuals who developed CVDs.

RESULTS

The mean age of the study participants was 73.4 years (SD: 10.4), and 62.1% were female individuals. During an average period of 5 years (mean: 5.18; SD: 2.96 years), 376 cases with incident dementia were identified. There was a 70% increased hazard of dementia per unit increase of PM2.5 during the 5 years before baseline (hazard ratio [HR]: 1.71; 95% CI 1.33-2.09). Overall, 50% (51.6%; 95% CI 9.0-94.1) of the total effect of PM2.5 on dementia was due to mediation of tHcy (6.6%; 95% CI 1.6-11.6) and/or interaction (47.8%; 95% CI 4.9-91.7) with tHcy and 48.4% (p = 0.03) to the direct effect of PM2.5 on dementia. High levels of methionine reduced the dementia hazard linked to PM2.5 by 31% (HR: 0.69; 95% CI 0.56-0.85) with 24.8% attributable to the interaction with methionine and 25.9% (p = 0.001) to the direct effect of PM2.5. No mediation effect was found through methionine. Attenuated results were obtained for NOx. Findings for tHcy were attenuated after excluding those who developed CVDs, while remained similar for methionine.

DISCUSSION

High levels of homocysteine enhanced the dementia risk attributed to air pollution, while high methionine concentrations reduced this risk. The impact of homocysteine on cardiovascular conditions partly explains this association. Alternative pathways other than cardiovascular mechanisms may be at play between methionine and dementia.

Determination of underivatized amino acids in human plasma using ion pair liquid chromatography/tandem mass spectrometry

Accurate quantification of amino acids (AA) is essential for several applications, including clinical research, food analysis, and pharmaceutical studies. In this study, we developed an analytical method based on liquid chromatography with electrospray ionization coupled to tandem mass spectrometry detection (LC-ESI-MS/MS). This method was devised to accurately quantify a spectrum of amino acids, notably taurine, creatinine, glutathione (GSH), and sulfur-containing amino acids (SAAs) such as methionine, cysteine, and homocysteine, using only 10 μL of human plasma. A stable isotope derivative of each AA is used as an internal standard (IS) for accurate quantification. For retention and separation on a C18 column, heptafluorobutyric acid (HFBA) was employed as an ion pair agent. Multiple reaction monitoring (MRM) in positive mode with the precursor-to-product ion transitions at m/z is used for quantification. The method showed excellent linearity for all AA with a high correlation coefficient (r > 0.9927). The linear fit indicates that the detector response is linear over the tested range of standard concentrations. The accuracy and precision of the method were within the acceptable range of 92-110% and < 15%, respectively. The limit of detection (LOD) and limit of quantification (LOQ) were in the range of 0.001-1.80 µM and 0.004-6.0 µM, respectively. No significant ion suppression or carry over was observed. In conclusion, the assay was validated and found to have adequate accuracy, precision, linearity, sensitivity and selectivity. The assay has been successfully applied to the analysis of human plasma.

Association of hyperhomocysteinemia and chronic kidney disease in the general population: a systematic review and meta-analysis

BACKGROUND

Increasing evidence shows that an elevated homocysteine(Hcy) level is associated with an increased risk of chronic kidney disease (CKD). This study systematically evaluated the correlation between homocysteine level and the incidence of CKD reported in cohort and cross-sectional studies.

METHODS

We searched electronic databases and reference lists for relevant articles. 4 cohort studies and 7 cross-sectional studies including 79,416 patients were analyzed in a meta-analysis. Hyperhomocysteinemia was defined as a Hcy level > 15 µmol/L, which was the criterium used in previous studies. Meta-analyses were conducted of literature searches from online databases such as PubMed, Embase, Cochrane and Scopus. Computed pooled adjusted odds ratios with corresponding 95% confidence intervals (95% CI) were used to estimate the risk of new-onset CKD according to Hcy levels in the general population.

RESULTS

People with high Hcy levels were more likely to suffer from CKD than people with normal Hcy levels (pooled OR, 2.09; 95% CI, 1.72-2.55). This positive relationship persisted across different study types such as cohort studies (summary OR, 2.2; 95% CI, 1.55-3.13) and cross-sectional studies (summary OR, 2.07; 95% CI, 1.63-2.63).

CONCLUSIONS

People with hyperhomocysteinemia have a higher incidence of CKD, Hyperhomocysteinemia may also be an independent risk factor for CKD in the general population.

Correlation Analysis and Diagnostic Value of Serum Homocysteine, Cystatin C and Uric Acid Levels with the Severity of Coronary Artery Stenosis in Patients with Coronary Heart Disease

Background

Coronary angiography (CAG) is an invasive examination with high risks and costs and various complications may occur. It is necessary to find a diagnostic method, non-invasiveness, inexpensive with low risk. This study aims to analyze the correlation between the levels of serum homocysteine (Hcy), cystatin C (Cys C) and uric acid (UA) and Gensini score in patients with coronary heart disease (CHD) and assess their diagnostic value for CHD.

Methods

A retrospective analysis was conducted on 1412 patients underwent CAG from October 2019 to December 2021, and we conducted this study from January to July 2022. A total of 765 patients with CHD confirmed by CAG were selected as the research group, while 647 patients revealed as non-obstructive stenosis by CAG as the control group. The serum Hcy, Cys C and UA levels were detected and the correlation between Gensini score and variables was analyzed. The receiver-operating characteristic (ROC) curve was performed to assess the diagnostic value of the Hcy, Cys C and UA for CHD.

Results

The serum Hcy, Cys C and UA levels in the research group were higher as compared with the control group (p<0.05). Spearman correlation and multivariate linear regression analysis showed that there was a significantly positive correlation between Gensini score and serum Hcy, Cys C and UA levels (p<0.05). The ROC curve analysis presented the combined Hcy and Cys C with UA having the highest specificity of diagnostic value for CHD (area under the curve (AUC)=0.768, 95% CI 0.706-0.823, specificity = 72.34%, sensitivity = 67.88%, Youden Index = 0.4022).

Conclusion

The serum Hcy, Cys C and UA levels in patients with CHD were significantly increased, positive correlation with Gensini score. The combined Hcy and Cys C with UA could be used to assess the severity of coronary artery stenosis and provide predictive and early intervention treatment values for CHD and a new way of diagnosing CHD, which is cheap, safe, effective and deserving of clinical application.

Plasma homocysteine levels and associated factors in community-dwelling adolescents: the EVA-TYROL study

Background

Homocysteine (Hcy) has been associated with an adverse cardiovascular risk profile in adolescents. Assessment of the association between plasma Hcy levels and clinical/laboratory factors might improve our understanding of the pathogenesis of cardiovascular disease.

Methods

Hcy was measured in 1,900 14- to 19-year-old participants of prospective population-based EVA-TYROL Study (44.3% males, mean age 16.4 years) between 2015 and 2018. Factors associated with Hcy were assessed by physical examination, standardized interviews, and fasting blood analysis.

Results

Mean plasma Hcy was 11.3 ± 4.5 µmol/L. Distribution of Hcy was characterized by extreme right skew. Males exhibited higher Hcy and sex differences increased with increasing age. Univariate associations with Hcy emerged for age, sex, body mass index, high-density lipoprotein cholesterol, and for factors pertaining to blood pressure, glucose metabolism, renal function, and diet quality, whereas the most important multivariate predictors of Hcy were sex and creatinine.

Discussion

Clinical and laboratory factors associated with Hcy in adolescents were manifold, with sex and high creatinine identified as strongest independent determinants. These results may aid when interpreting future studies investigating the vascular risk of homocysteine.

Homocysteine-a retrospective and prospective appraisal

The biologically important amino acid homocysteine links sulfur, methionine, and one-carbon metabolism. This review describes its initial discovery, the identification of the clinical condition of "homocystinuria" and the recognition of its close relationship to folate and vitamin B12 metabolism. It discusses the history behind its current association with diverse diseases including neural tube defects, cardio- and cerebrovascular disease and, more recently, dementia and Alzheimer's Disease. It also explores current controversies and considers potential future research directions. It is intended to give a general overview of homocysteine in relation to health and disease.

General Strategy for Specific Fluorescence Imaging of Homocysteine in Living Cells and In Vivo

The aberrantly changed level of homocysteine (Hcy) triggers a variety of pathological symptoms and subsequently Hcy-related diseases. Direct and selective visualization of Hcy in biological systems is pivotal to understanding the pathological functions of Hcy at the molecular level. Herein, a general strategy was developed for the specific fluorescence imaging of Hcy through the combination of dual-binding sites and the introduction of a nitro group at the 6-position of the 7-diethylaminocoumarin fluorophore. Also, a series of novel fluorescent probes were exploited for monitoring Hcy with excellent selectivity, high sensitivity, and far-red/near-infrared fluorescence emission. Furthermore, fluorescence imaging of endogenous Hcy dynamics in living cells and in vivo was achieved, providing direct and solid evidence for the increasement of endogenous Hcy in type 2 diabetes mellitus and Alzheimer's disease. This research will greatly advance the development and understanding of the molecular nexus between the Hcy metabolism cascade and the root causes of diseases related to Hcy.

B-vitamin treatment modifies the mortality risk associated with calcium channel blockers in patients with suspected stable angina pectoris: A prospective cohort study

BACKGROUND

Calcium channel blockers (CCBs) are used for the treatment of cardiovascular disease (CVD), including angina pectoris, and hypertension; however, the effect on survival remains uncertain. CCBs impair fibrinolysis and have been linked to elevated plasma homocysteine (Hcy), a CVD risk marker.

OBJECTIVE

We explored the association between CCB use and mortality in a large prospective cohort of patients with suspected stable angina pectoris (SAP), and potential effect modifications by Hcy-lowering B-vitamin treatment (folic acid, B₁₂ and/or B₆) as 61.8% of the patients participated in a randomized placebo-controlled B-vitamin intervention trial.

METHODS

Patient baseline continuous characteristics according to CCB treatment were tested by linear regression. Hazard ratios (HRs) for mortality associated with CCB treatment, also according to B-vitamin intervention, were examined using Cox regression analysis. The multivariable model included cardiovascular risk factors, medical histories, and use of CVD medications.

RESULTS

A total of 3991 patients (71.5 % men) were included, of whom 907 were prescribed CCBs at discharge. During 10.3 years of median follow-up, 20.6% died and 8.9% from cardiovascular- and 11.6% from non-cardiovascular causes. Patients treated with CCBs had higher plasma Hcy, fibrinogen levels and erythrocyte sedimentation rate (all P<0.001). Further, CCB use was positively associated with mortality, also after multivariable adjustments (HRs [95% CIs]: 1.34 [1.15-1.57], 1.35 [1.08-1.70] and 1.33 [1.09-1.64] for total, CVD and non-CVD death, respectively). Numerically stronger associations were observed among patients not treated with B-vitamins (HR [95% CI]: 1.54 [1.25-1.88], 1.69 [1.25-2.30] and 1.41 [1.06- 1.86] for total, CVD and non-CVD death, respectively), whereas, no association was seen in patients treated with B-vitamins (HR [95% CI]: 1.15 [0.91-1.46], 1.09 [0.76-1.57] and 1.20 [0.88-1.65]).

CONCLUSIONS

In patients with suspected SAP, CCB treatment was associated with increased mortality risk primarily among patients not treated with B-vitamins.

CLINICAL TRIAL REGISTRATION-URL

https://clinicaltrials.gov/ct2/show/NCT00354081?term=NCT00354081&draw=2&rank=1. Clinical Trial Registration-Unique identifier (NCT number): NCT00354081.

Proteomic Exploration of Paraoxonase 1 Function in Health and Disease

High-density lipoprotein (HDL) exhibits cardio- and neuro-protective properties, which are thought to be promoted by paraoxonase 1 (PON1), a hydrolytic enzyme associated with an HDL subfraction also enriched with an anticoagulant protein (PROS1) and amyloid beta-transport protein clusterin (CLU, APOJ). Reduced levels of PON1 activity, characterized biochemically by elevated levels of homocysteine (Hcy)-thiolactone, oxidized lipids, and proteins modified by these metabolites in humans and mice, are associated with pathological abnormalities affecting the cardiovascular system (atherothrombosis) and the central nervous system (cognitive impairment, Alzheimer's disease). The molecular bases of these abnormalities have been largely unknown. Proteomic and metabolic studies over the past decade have significantly contributed to our understanding of PON1 function and the mechanisms by which PON1 deficiency can lead to disease. Recent studies discussed in this review highlight the involvement of dysregulated proteostasis in the pro-oxidative, pro-atherothrombotic, and pro-amyloidogenic phenotypes associated with low PON1 activity.

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.