Homocysteine and Mitochondria in Cardiovascular and Cerebrovascular Systems

N6-methyldeoxyadenosine modification difference contributes to homocysteine-induced mitochondrial perturbation in rat hippocampal primary neurons and PC12 cells

Elevated homocysteine (Hcy) levels are detrimental to neuronal cells and contribute to cognitive dysfunction in rats. Mitochondria plays a crucial role in cellular energy metabolism. Interestingly, the damaging effects of Hcy in vivo and in vitro conditions exhibit distinct results. Herein, we aimed to investigate the effects of Hcy on mitochondrial function in primary neurons and PC12 cells and explore the underlying mechanisms involved. The metabolic intermediates of Hcy act as methyl donors and play important epigenetic regulatory roles. N6-methyldeoxyadenosine (6 mA) modification, which is enriched in mitochondrial DNA (mtDNA), can be mediated by methylase METTL4. Our study suggested that mitochondrial perturbation caused by Hcy in primary neurons and PC12 cells may be attributable to mtDNA 6 mA modification difference. Hcy could activate the expression of METTL4 within mitochondria to facilitate mtDNA 6 mA status, and repress mtDNA transcription, then result in mitochondrial dysfunction.

Homocysteine in androgenetic alopecia: A case control study and observational experiments on mice

OBJECTIVE

To investigate the relationship between homocysteine (HCY) and androgenetic alopecia (AGA).

METHODS

A case control study and two observational experiments on mice were conducted. In the first part, a total of 528 Chinese AGA patients and 500 age-matched healthy controls were included. Serum HCY levels of AGA and controls were compared. In the second part, eight mice were divided into two groups. Both groups of mice had their hair removed. AGA group received a DHT injection, and the other as control group. HCY levels in hair follicles (HFs) were detected by ELISA and compared. In the third part, twelve mice were divided into three groups and fed with different concentrations of methionine. After 4 weeks, serum HCY levels, parameters related to hair growth through observation and HE staining, and expression of immunohistochemistry (IHC) hair-growth-related markers Ki67, VEGF, IGF-1, Krt27, FGF9, and TGF-β1 were compared among the three groups.

RESULTS

In the first part, HCY levels were higher in AGA than the controls of both genders. However, there was no difference in HCY levels between groups with varying severity. Rates of hyperhomocysteinemia was higher in AGA patients than the controls. Logistic regression analysis showed serum HCY levels was positively correlated with the incidence of AGA. In the second part, HCY of the HFs in the AGA group was significantly higher than that in the control group. The third part showed that the increase in serum HCY levels inhibited the growth of mice hair, with the less expressed stimulative markers Ki67, VEGF, IGF-1, Krt27, and FGF9, while there was no difference in the expression of inhibitory markers TGF-β1.

CONCLUSION

There is a potential relationship between HCY and AGA. HCY had an inhibitory effect on hair growth. Further studies are necessary to explore the specific mechanism.

Nicotinamide N-Methyltransferase (NNMT): A New Hope for Treating Aging and Age-Related Conditions

The complex process of aging leads to a gradual deterioration in the function of cells, tissues, and the entire organism, thereby increasing the risk of disease and death. Nicotinamide N-methyltransferase (NNMT) has attracted attention as a potential target for combating aging and its related pathologies. Studies have shown that NNMT activity increases over time, which is closely associated with the onset and progression of age-related diseases. NNMT uses S-adenosylmethionine (SAM) as a methyl donor to facilitate the methylation of nicotinamide (NAM), converting NAM into S-adenosyl-L-homocysteine (SAH) and methylnicotinamide (MNA). This enzymatic action depletes NAM, a precursor of nicotinamide adenine dinucleotide (NAD+), and generates SAH, a precursor of homocysteine (Hcy). The reduction in the NAD+ levels and the increase in the Hcy levels are considered important factors in the aging process and age-related diseases. The efficacy of RNA interference (RNAi) therapies and small-molecule inhibitors targeting NNMT demonstrates the potential of NNMT as a therapeutic target. Despite these advances, the exact mechanisms by which NNMT influences aging and age-related diseases remain unclear, and there is a lack of clinical trials involving NNMT inhibitors and RNAi drugs. Therefore, more in-depth research is needed to elucidate the precise functions of NNMT in aging and promote the development of targeted pharmaceutical interventions. This paper aims to explore the specific role of NNMT in aging, and to evaluate its potential as a therapeutic target.

Nicotinamide N-methyltransferase (NNMT): a novel therapeutic target for metabolic syndrome

Metabolic syndrome (MetS) represents a constellation of metabolic abnormalities, typified by obesity, hypertension, hyperglycemia, and hyperlipidemia. It stems from intricate dysregulations in metabolic pathways governing energy and substrate metabolism. While comprehending the precise etiological mechanisms of MetS remains challenging, evidence underscores the pivotal roles of aberrations in lipid metabolism and insulin resistance (IR) in its pathogenesis. Notably, nicotinamide N-methyltransferase (NNMT) has recently surfaced as a promising therapeutic target for addressing MetS. Single nucleotide variants in the NNMT gene are significantly correlated with disturbances in energy metabolism, obesity, type 2 diabetes (T2D), hyperlipidemia, and hypertension. Elevated NNMT gene expression is notably observed in the liver and white adipose tissue (WAT) of individuals with diabetic mice, obesity, and rats afflicted with MetS. Knockdown of NNMT elicits heightened energy expenditure in adipose and hepatic tissues, mitigates lipid accumulation, and enhances insulin sensitivity. NNMT catalyzes the methylation of nicotinamide (NAM) using S-adenosyl-methionine (SAM) as the donor methyl group, resulting in the formation of S-adenosyl-l-homocysteine (SAH) and methylnicotinamide (MNAM). This enzymatic process results in the depletion of NAM, a precursor of nicotinamide adenine dinucleotide (NAD+), and the generation of SAH, a precursor of homocysteine (Hcy). Consequently, this cascade leads to reduced NAD+ levels and elevated Hcy levels, implicating NNMT in the pathogenesis of MetS. Moreover, experimental studies employing RNA interference (RNAi) strategies and small molecule inhibitors targeting NNMT have underscored its potential as a therapeutic target for preventing or treating MetS-related diseases. Nonetheless, the precise mechanistic underpinnings remain elusive, and as of yet, clinical trials focusing on NNMT have not been documented. Therefore, further investigations are warranted to elucidate the intricate roles of NNMT in MetS and to develop targeted therapeutic interventions.

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.

Mild hyperhomocysteinemia alters oxidative stress profile via Nrf2, inflammation and cholinesterases in cardiovascular system of aged male rats

Homocysteine (Hcy) is an independent cardiovascular disease (CVD) risk factor, whose mechanisms are poorly understood. We aimed to explore mild hyperhomocysteinemia (HHcy) effects on oxidative status, inflammatory, and cholinesterase parameters in aged male Wistar rats (365 days old). Rats received subcutaneous Hcy (0.03 μmol/g body weight) twice daily for 30 days, followed by euthanasia, blood collection and heart dissection 12 h after the last injection. Results revealed increased dichlorofluorescein (DCF) levels in the heart and serum, alongside decreased antioxidant enzyme activities (superoxide dismutase, catalase, glutathione peroxidase), reduced glutathione (GSH) content, and diminished acetylcholinesterase (AChE) activity in the heart. Serum butyrylcholinesterase (BuChE) levels also decreased. Furthermore, nuclear factor erythroid 2-related factor 2 (Nrf2) protein content decreased in both cytosolic and nuclear fractions, while cytosolic nuclear factor kappa B (NFκB) p65 increased in the heart. Additionally, interleukins IL-1β, IL-6 and IL-10 showed elevated expression levels in the heart. These findings could suggest a connection between aging and HHcy in CVD. Reduced Nrf2 protein content and impaired antioxidant defenses, combined with inflammatory factors and altered cholinesterases activity, may contribute to understanding the impact of Hcy on cardiovascular dynamics. This study sheds light on the complex interplay between HHcy, oxidative stress, inflammation, and cholinesterases in CVD, providing valuable insights for future research.

Is There a Connection between Hyperhomocysteinemia and the Cardiometabolic Syndrome?

This study investigates the distribution of hyperhomocysteinemia and cardiovascular metabolic syndrome (SM) among participants, shedding light on their prevalence and co-occurrence within the study cohort. Through an analysis of demographic characteristics and health parameters, including age, gender, and body mass index (BMI), alongside nutritional data, correlations between these factors and health risks are explored. Results reveal a notable prevalence of hyperhomocysteinemia, with 45.3% of participants exhibiting this condition. Furthermore, 31.4% of the cohort does not present hyperhomocysteinemia or SM, while 23.3% shows SM without hyperhomocysteinemia. The study underscores gender-specific dietary recommendations due to significant variations in nutrient intake patterns. Additionally, inverse correlations between health risks like obesity, hypertension, and hypercholesterolemia and nutrient requirements highlight the need for tailored dietary interventions. Age-related changes in nutrient needs and the positive correlation between physical activity levels and certain nutrient demands further emphasize the importance of personalized dietary strategies. Variations in nutrient intake by gender, inverse correlations with health risks, and age-related changes underscore the need for tailored dietary strategies. These findings provide valuable insights for healthcare professionals in developing targeted nutritional interventions to mitigate disease risk and promote overall health and well-being.

Associations of serum vitamin B12 and its biomarkers with musculoskeletal health in middle-aged and older adults

Introduction

The effects of vitamin B12 metabolism on musculoskeletal health and the exact mechanism have not been fully determined. Our study aimed to assess the association of vitamin B12 and its biomarkers with musculoskeletal health in middle-aged and older adults.

Methods

The data from the National Health and Nutrition Examination Survey 2001-2002 were used to investigate the effects of serum vitamin B12 and its biomarkers (homocysteine and methylmalonic acid) on skeletal muscle health. Bone mineral density (BMD), lean mass, gait speed and knee extensor strength were used as indicators for musculoskeletal health.

Results

Serum vitamin B12 level was positively correlated with the total and appendicular lean mass (β = 584.83, P = 0.044; β = 291.65, P = 0.043) in older adults over 65 years of age. In the full population, plasma homocysteine was associated with total lean mass, appendicular lean mass, gait speed, and knee extensor strength (all P < 0.05). Among older adults over 65 years of age, homocysteine level was significantly negatively correlated with gait speed and knee extensor strength (β = -12.75, P = 0.019; β = -0.06, P <0.001). Plasma methylmalonic acid was negatively associated with total BMD and femur BMD in the full population (β = -0.01, P = 0.018; β = -0.01, P = 0.004). In older adults, methylmalonic acid significantly affected total BMD, femur BMD and knee extensor strength (β = -0.01, P = 0.048; β = -0.01, P = 0.025; β = -7.53, P = 0.015).

Conclusions

Vitamin B12 and its biomarkers are closely related to BMD, body composition, muscle strength and physical function in middle-aged and older adults. Vitamin B12 may be an important indicator of musculoskeletal health in the elderly.

Association between homocysteine and blood pressure in the NHANES 2003-2006: the mediating role of Vitamin C

Background

The yearly escalation in hypertension prevalence signifies a noteworthy public health challenge. Adhering to a nutritious diet is crucial for enhancing the quality of life among individuals managing hypertension. However, the relationship between vitamin C and hypertension, as well as homocysteine, remains unclear.

Objective

The primary aim of this investigation was to scrutinize the potential mediating role of Vitamin C in the association between homocysteine levels and blood pressure, utilizing data extracted from the National Health and Nutrition Examination Survey (NHANES) database.

Methods

A total of 7,327 participants from the NHANES 2003-2006 were enrolled in this cross-sectional survey. The main information was obtained using homocysteine, Vitamin C, systolic blood pressure (SBP) and diastolic blood pressure (DBP). Correlation analysis was used to assess the correlation between homocysteine, SBP, DBP and vitamin C. Linear regression analysis was utilized to determine the β value (β) along with its 95% confidence intervals (CIs). Mediation analysis was performed to investigate whether the relationship between homocysteine and blood pressure was mediated by Vitamin C, and to quantify the extent to which Vitamin C contributed to this association.

Results

The results manifested that the homocysteine was positively associated with SBP (r = 0.24, p < 0.001) and DBP (r = 0.03, p < 0.05), while negatively correlated with Vitamin C (r = -0.008, p < 0.001). Vitamin C was found to be negatively associated with SBP (r = -0.03, p < 0.05) and DBP (r = 0.11, p < 0.001). Mediation effect analysis revealed that a partial mediation (indirect effect: 0.0247[0.0108-0.0455], p < 0.001) role accounting for 11.5% of total effect, among homocysteine and SBP. However, the mediating effect of Vitamin C between homocysteine and DBP was not statistically significant.

Conclusion

Hypertension patients should pay attention to homocysteine and Vitamin C level. What is more, hypertension patients ought to formulate interventions for Vitamin C supplementation as well as homocysteine reduce strategies to lower blood pressure.

Implications of high homocysteine levels in migraine pain: An experimental study of the excitability of peripheral meningeal afferents in rats with hyperhomocysteinemia

OBJECTIVES

Investigation of chronic homocysteine action on the excitability and N-methyl-D-aspartate (NMDA) sensitivity of the peripheral trigeminovascular system of rats.

BACKGROUND

Migraine is a neurological disease that affects 15%-20% of the general population. Epidemiological observations show that an increase of the sulfur-containing amino acid homocysteine in plasma-called hyperhomocysteinemia-is associated with a high risk of migraine, especially migraine with aura. In animal studies, rats with hyperhomocysteinemia demonstrated mechanical allodynia, photophobia, and anxiety, and higher sensitivity to cortical spreading depression. In addition, rats with hyperhomocysteinemia were more sensitive in a model of chronic migraine induced by nitroglycerin which indicated the involvement of peripheral nociceptive mechanisms. The present work aimed to analyze the excitability of meningeal afferents and neurons isolated from the trigeminal ganglion of rats with prenatal hyperhomocysteinemia.

METHODS

Experiments were performed on male rats born from females fed with a methionine-rich diet before and during pregnancy. The activity of meningeal afferents was recorded extracellularly in hemiskull preparations ex vivo and action potentials were characterized using cluster analysis. The excitability of trigeminal ganglion neurons was assessed using whole-cell patch clamp recording techniques and calcium imaging studies. Meningeal mast cells were stained using toluidine blue.

RESULTS

The baseline extracellular recorded electrical activity of the trigeminal nerve was higher in the hyperhomocysteinemia group with larger amplitude action potentials. Lower concentrations of KCl caused an increase in the frequency of action potentials of trigeminal afferents recorded in rat hemiskull ex vivo preparations. In trigeminal ganglion neurons of rats with hyperhomocysteinemia, the current required to elicit at least one action potential (rheobase) was lower, and more action potentials were induced in response to stimulus of 2 × rheobase. In controls, short-term application of homocysteine and its derivatives increased the frequency of action potentials of the trigeminal nerve and induced Ca2+ transients in neurons, which are associated with the activation of NMDA receptors. At the same time, in rats with hyperhomocysteinemia, we did not observe an increased response of the trigeminal nerve to NMDA. Similarly, the parameters of Ca2+ transients induced by NMDA, homocysteine, and its derivatives were not changed in rats with hyperhomocysteinemia. Acute incubation of the meninges in homocysteine and homocysteinic acid did not change the state of the mast cells, whereas in the model of hyperhomocysteinemia, an increased degranulation of mast cells in the meninges was observed.

CONCLUSIONS

Our results demonstrated higher excitability of the trigeminal system of rats with hyperhomocysteinemia. Together with our previous finding about the lower threshold of generation of cortical spreading depression in rats with hyperhomocysteinemia, the present data provide evidence of homocysteine as a factor that increases the sensitivity of the peripheral migraine mechanisms, and the control of homocysteine level may be an important strategy for reducing the risk and/or severity of migraine headache attacks.

Association between advanced lung cancer inflammation index and all-cause and cardiovascular mortality among stroke patients: NHANES, 1999-2018

Background

Stroke was a major global public health challenge, and its prognosis was remarkably associated with inflammation levels and nutritional status. The advanced lung cancer inflammation index (ALI) was a comprehensive indicator that combined inflammation and nutritional status. Currently, the relationship between ALI and the prognosis of stroke patients was not yet known. The purpose of the current study was to estimate their relationship.

Methods

Cohort data from the National Health and Nutrition Examination Survey (NHANES) 1999-2018 were collected. The association between ALI and all-cause and cardiovascular disease (CVD) mortality in stroke patients was estimated using a multivariable adjusted Cox model. Their non-linear relationship was analyzed by restricted cubic spline analysis. Sensitivity analysis was constructed through stratified analysis and interaction analysis.

Results

1,440 stroke patients were included in this study. An elevated ALI was significantly related to a reduced risk of all-cause mortality in stroke patients but not related to CVD mortality. A reverse J-shaped non-linear association between ALI and all-cause mortality in stroke patients, with an inflection point at 83.76 (the lowest of the mortality risk). On the left side of the inflection point, for each 10 U increase in ALI, there was a 16% reduction in the risk of all-cause mortality. However, on the right side, the risk increased by 6%. There was no remarkable interaction between stratified variables and ALI.

Conclusion

This was the first study on the relationship between ALI and all-cause and CVD mortality in stroke patients. Elevated ALI was closely associated with a reduced risk of all-cause mortality. A reverse J-shaped non-linear relationship existed between the two, with an inflection point at 83.76. These findings implied that controlling the ALI of stroke patients within an appropriate range was crucial for their prognosis (such as weight management, albumin supplementation, anti-inflammatory treatment). The dynamic variation in ALI was also advantageous for clinicians in establishing personalized ALI criteria to maximize the long-term survival of stroke patients.

Association between Homocysteine and Vitamin D Levels in Asymptomatic Korean Adults

An increased homocysteine level is a risk factor for cardiovascular disease, venous thromboembolism, cerebrovascular disease, and chronic kidney disease. In addition, vitamin D deficiency is associated with coronary artery disease and metabolic disorders. The present study included data from 1375 adults (895 men and 480 women) with a mean age of 52.62 ± 9.94 years who visited the Health Promotion Center of the University Hospital in Gyeonggi-do, Republic of Korea from January 2018 to December 2022 for routine checkups that included assessments of their homocysteine and vitamin D levels. Homocysteine levels were positively associated with age, a history of hypertension, a history of diabetes, current smoking habits, and levels of low-density lipoprotein cholesterol, creatinine, uric acid, and high-sensitivity C-reactive protein. By contrast, vitamin D levels were negatively associated with serum levels of homocysteine after adjusting for covariates (β = -0.033, p < 0.001). Additional long-term prospective studies are needed to elucidate the presence of a causal relationship between vitamin D status and serum levels of homocysteine in asymptomatic Korean adults. An intervention trial is warranted to determine whether the administration of vitamin D is helpful for the primary prevention of cardiovascular disease by lowering the homocysteine level in this population.

Plasma homocysteine level, estradiol level, and brain atrophy: a Mendelian randomization study

OBJECTIVES

Observational studies link elevated plasma homocysteine (Hcy) with vascular disease. Our aim was to assess the gender difference in the association between the plasma tHcy level and brain atrophy and identify the possible influencer. We employed Mendelian randomization (MR) to explore the causal relationship between plasma tHcy level, estradiol level, and brain atrophy.

METHODS

A total of 687 patients with brain atrophy were included, and gender-specific subgroup analyses in association between tHcy and brain atrophy are conducted. From genome-wide association studies, we selected genetic variants (P < 5 × 10-8) for the plasma tHcy level and estradiol level. We investigated the degree of brain atrophy (including gray matter volume and total brain volume) in the UK biobank (n = 7,916). The inverse variance-weighted and several sensitivity MR regression analyses were carried out.

RESULTS

The plasma tHcy level was significantly associated with brain atrophy for females, but not for males. An MR study showed that there was little evidence of the causal link between elevated plasma tHcy and brain atrophy. On the other hand, we found evidence to support causality for genetically decreased estradiol with higher risk of brain atrophy. Furthermore, genetic predisposition to elevated plasma tHcy was associated with a lower estradiol level.

CONCLUSIONS

The influence of estradiol on the association between tHcy and brain atrophy deserves further investigation.

Associations between one-carbon metabolism and valproic acid-induced liver dysfunction in epileptic patients

Valproic acid (VPA) has been widely used as an antiepileptic drug for decades. Although VPA is effective and well-tolerated, long-term VPA treatment is usually associated with hepatotoxicity. However, the underlying mechanisms of VPA-caused hepatotoxicity remain unclear. In this study, a total of 157 pediatric patients with epilepsy were recruited and divided into normal liver function (NLF, 112 subjects) group and abnormal liver function (ABLF, 45 subjects) group. We observed that MTHFR A1298C and MTHFR C677T variants may be linked to VPA-induced liver dysfunction (p = 0.001; p = 0.023, respectively). We also found that the MTHFR A1298C polymorphism was associated with a higher serum Hcy level (p = 0.001) and a lower FA level (p = 0.001). Moreover, the serum Hcy levels was strongly correlated with the GSH and TBARS concentrations (r = -0.6065, P < 0.001; r = 0.6564, P < 0.001, respectively). Furthermore, logistic analysis indicated that MTHFR A1298C/C677T polymorphisms and increased Hcy concentrations may be risk factors for VPA-induced liver dysfunction. These results suggested that individual susceptibility to VPA-induced liver dysfunction may result from MTHFR A1298C/C677T polymorphisms and increased Hcy levels. This study may be helpful for the prevention and guidance of VPA-induced liver dysfunction.

Mitochondrial-related genes PDK2, CHDH, and ALDH5A1 served as a diagnostic signature and correlated with immune cell infiltration in ulcerative colitis

We conducted an investigation to determine the potential of mitochondrial-related genes as diagnostic biomarkers in ulcerative colitis (UC), while also examining their association with immune cell infiltration. To achieve this, we acquired four datasets pertaining to UC, which included gene expression arrays and clinical data, from the GEO database. Subsequently, we selected three signature genes (PDK2, CHDH, and ALDH5A1) to construct a diagnostic model for UC. The nomogram and ROC curves exhibited exceptional diagnostic efficacy. Following this, quantitative real-time polymerase chain reaction and western blotting assays validated the decreased mRNA and protein expression of PDK2, CHDH, and ALDH5A1 in the model of UC cells and dextran sulfate sodium salt (DSS)-induced mice colitis tissues, aligning with the findings in the risk model. This investigation suggested a negative correlation between the expression of ALDH5A1, CHDH, and PDK2 and the infiltration of M1 macrophages. Then, immunofluorescence analysis confirmed the augmented expression of CD86 in the tissue of mice subjected to DSS, while a diminished expression of ALDH5A1, CHDH, and PDK2 was observed. Consequently, it can be inferred that targeting mitochondria-associated genes, namely PDK2, CHDH, and ALDH5A1, holds potential as a viable strategy for prognostic prediction and the implementation of immune therapy for UC.

Homocysteine serum levels in patients with ruptured and unruptured intracranial aneurysms: a case-control study

BACKGROUND

There is very few data regarding homocysteine's influence on the formation and rupture of intracranial aneurysms.

OBJECTIVE

To compare homocysteine levels between patients with ruptured and unruptured intracranial aneurysms, and to evaluate possible influences of this molecule on vasospasm and functional outcomes.

METHODS

This is a retrospective, case-control study. We evaluated homocysteinemia differences between patients with ruptured and unruptured aneurysms; and the association of homocysteine levels with vasospasm and functional outcomes. Logistic regressions were performed.

RESULTS

A total of 348 participants were included: 114 (32.8%) with previous aneurysm rupture and 234 (67.2%) with unruptured aneurysms. Median homocysteine was 10.75µmol/L (IQR = 4.59) in patients with ruptured aneurysms and 11.5µmol/L (IQR = 5.84) in patients with unruptured aneurysms. No significant association was detected between homocysteine levels and rupture status (OR = 0.99, 95% CI = 0.96-1.04). Neither mild (>15µmol/L; OR = 1.25, 95% CI 0.32-4.12) nor moderate (>30µmol/L; OR = 1.0, 95% CI = 0.54-1.81) hyperhomocysteinemia demonstrated significant correlations with ruptured aneurysms. Neither univariate (OR = 0.86; 95% CI 0.71-1.0) nor multivariable age-adjusted (OR = 0.91; 95% CI = 0.75-1.05) models evidenced an association between homocysteine levels and vasospasm. Homocysteinemia did not influence excellent functional outcomes at 6 months (mRS≤1) (OR = 1.04; 95% CI = 0.94-1.16).

CONCLUSION

There were no differences regarding homocysteinemia between patients with ruptured and unruptured intracranial aneurysms. In patients with ruptured aneurysms, homocysteinemia was not associated with vasospasm or functional outcomes.

Association of MTHFR polymorphism, folic acid and vitamin B12 with serum homocysteine levels in pregnant women

Homocysteine is known to be associated with adverse vascular and metabolic effects, as well as pregnancy complications. Its serum levels are influenced by the function of the enzyme methylenetetrahydrofolate reductase (MTHFR) and the dietary intake of folic acid, vitamin B12, and methionine. In this cross-sectional study, we investigated the association of genetic polymorphisms of the MTHFR gene with vitamin status in pregnant women during mandatory folic acid supplementation. The study included 102 pregnant women between 24 and 28 weeks of gestation who were attending regular outpatient examinations at the maternity clinic. Homocysteine, folic acid, vitamin B12 levels, and MTHFR gene polymorphisms (C677T and A1298C) were analyzed. Significant associations were found between vitamin B12 and folic acid levels with homocysteine (P < 0.001), with lower serum levels of these vitamins being associated with higher homocysteine levels. Surprisingly, there was no significant association between MTHFR genetic polymorphisms and serum homocysteine levels, likely attributed to the supplementation of folic acid and vitamin B12 in vitamin supplements for pregnant women, which counteracts the effect of the mutation. Remarkably, a high prevalence of MTHFR gene mutations was found, with the C677T polymorphism present in 56.9% and the A1298C polymorphism in 87.2% of pregnant women. These findings emphasize the importance of adequate folic acid and vitamin B12 intake during pregnancy to regulate homocysteine levels. Although the MTHFR gene mutations were highly prevalent, their influence on homocysteine levels in this population appears to be mitigated by vitamin supplementation. Further research is warranted to explore the impact of these mutations on other aspects of pregnancy outcomes. The trial is registrated at Clinicaltrail.gov (NCT04952324).

The Implication of a Polymorphism in the Methylenetetrahydrofolate Reductase Gene in Homocysteine Metabolism and Related Civilisation Diseases

Methylenetetrahydrofolate reductase (MTHFR) is a key regulatory enzyme in the one-carbon cycle. This enzyme is essential for the metabolism of methionine, folate, and RNA, as well as for the production of proteins, DNA, and RNA. MTHFR catalyses the irreversible conversion of 5,10-methylenetetrahydrofolate to its active form, 5-methyltetrahydrofolate, a co-substrate for homocysteine remethylation to methionine. Numerous variants of the MTHFR gene have been recognised, among which the C677T variant is the most extensively studied. The C677T polymorphism, which results in the conversion of valine to alanine at codon 222, is associated with reduced activity and an increased thermolability of the enzyme. Impaired MTHFR efficiency is associated with increased levels of homocysteine, which can contribute to increased production of reactive oxygen species and the development of oxidative stress. Homocysteine is acknowledged as an independent risk factor for cardiovascular disease, while chronic inflammation serves as the common underlying factor among these issues. Many studies have been conducted to determine whether there is an association between the C677T polymorphism and an increased risk of cardiovascular disease, hypertension, diabetes, and overweight/obesity. There is substantial evidence supporting this association, although several studies have concluded that the polymorphism cannot be reliably used for prediction. This review examines the latest research on MTHFR polymorphisms and their correlation with cardiovascular disease, obesity, and epigenetic regulation.

Homocysteine impairs the anticontractile/vasorelaxing activity of perivascular adipose tissue surrounding human internal mammary artery

OBJECTIVES

Perivascular adipose tissue (PVAT) surrounding human internal mammary artery (IMA) possesses anticontractile property. Its function under pathological conditions is barely studied. We previously reported that homocysteine impairs the vasodilator function of IMA through endothelium and smooth muscle-dependent mechanisms. This study investigated the effect of homocysteine on the function of PVAT and the associated mechanisms.

METHODS

Residual IMA tissues were collected from patients undergoing coronary artery bypass grafting. Vasoreactivity was studied using myograph. Adiponectin was measured by ELISA. Expressions of adiponectin receptors (AdipoRs), eNOS and p-eNOS were determined by RT-qPCR and Western blot.

RESULTS

Exposure to homocysteine augmented the contractile responses of PVAT-intact IMA to U46619 and potassium chloride, regardless with or without endothelium. Such augmentation was also observed in skeletonized IMA with transferred, homocysteine-exposed PVAT. Homocysteine attenuated the relaxant response of PVAT-intact while endothelium-denuded vessels to acetylcholine. Homocysteine lowered adiponectin content in the PVAT, downregulated the expression of AdipoR1 and AdipoR2 as well as eNOS and p-eNOS in skeletonized IMA. The relaxant response of skeletonized IMA to AdipoR agonist AdipoRon was blunted by homocysteine or eNOS inhibitor, and homocysteine significantly attenuated the inhibitory effect of eNOS inhibitor on AdipoRon-induced relaxation.

CONCLUSIONS

Homocysteine impairs the anticontractile/vasorelaxing activity of PVAT surrounding the IMA through inhibiting adiponectin/AdipoR/eNOS/nitric oxide signalling pathway.

Hyperhomocysteinemia lowers serum testosterone concentration via impairing testosterone production in Leydig cells

Hyperhomocysteinemia (HHcy) plays a salient role in male infertility. However, whether HHcy interferes with testosterone production remains inconclusive. Here, we reported a lower serum testosterone level in HHcy mice. Single-cell RNA sequencing revealed that genes related to testosterone biosynthesis, together with nuclear receptor subfamily 5 group A member 1 (Nr5a1), a key transcription factor for steroidogenic genes, were downregulated in the Leydig cells (LCs) of HHcy mice. Mechanistically, Hcy lowered trimethylation of histone H3 on lysine 4 (H3K4me3), which was bound on the promoter region of Nr5a1, resulting in downregulation of Nr5a1. Intriguingly, we identified an unknown cell cluster annotated as Macrophage-like Leydig cells (McLCs), expressing both LCs and macrophages markers. In HHcy mice, McLCs were shifted toward pro-inflammatory phenotype and thus promoted inflammatory response in LC. Betaine supplementation rescued the downregulation of NR5A1 and restored the serum testosterone level in HHcy mice. Overall, our study highlights an etiological role of HHcy in LCs dysfunction.

Sensitively detecting endogenous homocysteine in human serum and cardiomyocytes with a specific fluorescent probe

The elevated level of homocysteine (Hcy) in circulating blood is generally regarded as a risk factor for a variety of diseases including acute myocardial infarction (AMI), but there is no clear answer to whether circulating Hcy can be used for AMI diagnosis. To address it, here we have designed a tetraazacycle-based fluorescent probe for sensitive detection of endogenous Hcy in AMI patients' serum and cardiomyocytes, showing a perfect selectivity over other biothiols (e.g. Cys and GSH). It mainly relies on the formation of a stable six-membered ring structure when this probe responds to Hcy, which is accompanied by a weakening of photoinduced electron transfer (PET) that induces a sharp increase in the fluorescence emission. In this way, Hcy can be probed in biofluids with high sensitivity. We then employed this fluorescent sensor to statistically analyze the levels of Hcy in human circulating blood, indicating a big difference between AMI patients and the healthy participants. To tell whether such a difference is applicable to AMI diagnosis, we further compare the expression levels of Hcy in cardiomyocytes and other tissue cells. It reveals a lower level of endogenous Hcy in cardiomyocytes, implying no direct relationship between the elevated Hcy and cardiomyocyte damage. This observation suggests that Hcy in circulating blood cannot be utilized as a potential biomarker for AMI diagnosis, although it is proven as a risk factor for this disease.

The Role of Methionine-Rich Diet in Unhealthy Cerebrovascular and Brain Aging: Mechanisms and Implications for Cognitive Impairment

As aging societies in the western world face a growing prevalence of vascular cognitive impairment and Alzheimer's disease (AD), understanding their underlying causes and associated risk factors becomes increasingly critical. A salient concern in the western dietary context is the high consumption of methionine-rich foods such as red meat. The present review delves into the impact of this methionine-heavy diet and the resultant hyperhomocysteinemia on accelerated cerebrovascular and brain aging, emphasizing their potential roles in cognitive impairment. Through a comprehensive exploration of existing evidence, a link between high methionine intake and hyperhomocysteinemia and oxidative stress, mitochondrial dysfunction, inflammation, and accelerated epigenetic aging is drawn. Moreover, the microvascular determinants of cognitive deterioration, including endothelial dysfunction, reduced cerebral blood flow, microvascular rarefaction, impaired neurovascular coupling, and blood-brain barrier (BBB) disruption, are explored. The mechanisms by which excessive methionine consumption and hyperhomocysteinemia might drive cerebromicrovascular and brain aging processes are elucidated. By presenting an intricate understanding of the relationships among methionine-rich diets, hyperhomocysteinemia, cerebrovascular and brain aging, and cognitive impairment, avenues for future research and potential therapeutic interventions are suggested.

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.

Folic Acid Protects against Ethanol-Induced Hepatic Mitophagy Imbalance by ROS Scavenging and Attenuating the Elevated Hcy Levels

Ample evidence indicates that ethanol-induced oxidative stress and mitochondrial dysfunction are central to the pathogenesis of alcoholic liver disease (ALD). As an adaptive quality control mechanism, mitophagy removes dysfunctional mitochondria to avert hepatic lesions in ALD. Folic acid exhibits potential radical scavenging properties and has been proven to ameliorate mitochondrial disorder in oxidative stress-related diseases. In this study, we aimed to uncover the mitophagy regulatory effects of folic acid in a 10w alcohol C57BL/6J mice feeding model (56% v/v) and L02 cells model cultured with ethanol (2.5% v/v). The results showed that folic acid alleviates ethanol-induced liver injury, decreasing oxidative stress and restoring liver enzyme. Furthermore, folic acid improved the mitochondrial function and inhibited ethanol-activated mitophagy through decreasing PINK1-Parkin and Drp1 expression, which inhibited the release of mitochondrial cytochrome C to the cytoplasm, preventing hepatocyte apoptosis. Intriguingly, folic acid attenuates the elevated hepatic homocysteine (Hcy) level. Additionally, the pretreatment of L02 cells with folic acid also ameliorated Hcy-induced oxidative damage, mitochondrial fission, and mitophagy. In summary, these results suggest that folic acid has beneficial effects in mitophagy remodeling by ROS scavenging and facilitating Hcy metabolism and could be developed as a potential therapeutic agent against ALD.

Defective quality control autophagy in Hyperhomocysteinemia promotes ER stress and consequent neuronal apoptosis through proteotoxicity

Homocysteine (Hcy), produced physiologically in all cells, is an intermediate metabolite of methionine and cysteine metabolism. Hyperhomocysteinemia (HHcy) resulting from an in-born error of metabolism that leads to accumulation of high levels of Hcy, is associated with vascular damage, neurodegeneration and cognitive decline. Using a HHcy model in neuronal cells, primary cortical neurons and transgenic zebrafish, we demonstrate diminished autophagy and Hcy-induced neurotoxicity associated with mitochondrial dysfunction, fragmentation and apoptosis. We find this mitochondrial dysfunction is due to Hcy-induced proteotoxicity leading to ER stress. We show this sustained proteotoxicity originates from the perturbation of upstream autophagic pathways through an aberrant activation of mTOR and that protetoxic stress act as a feedforward cues to aggravate a sustained ER stress that culminate to mitochondrial apoptosis in HHcy model systems. Using chemical chaperones to mitigate sustained ER stress, Hcy-induced proteotoxicity and consequent neurotoxicity were rescued. We also rescue neuronal lethality by activation of autophagy and thereby reducing proteotoxicity and ER stress. Our findings pave the way to devise new strategies for the treatment of neural and cognitive pathologies reported in HHcy, by either activation of upstream autophagy or by suppression of downstream ER stress. Video Abstract.

Homocysteine Modulates Social Isolation-Induced Depressive-Like Behaviors Through BDNF in Aged Mice

Social isolation is an unpleasant experience associated with an increased risk of mental disorders. Exploring whether these experiences affect behaviors in aged people is particularly important, as the elderly is very likely to suffer from periods of social isolation during their late-life. In this study, we analyzed the depressive-like behaviors, plasma concentrations of homocysteine (Hcy), and brain-derived neurotropic factor (BDNF) levels in aged mice undergoing social isolation. Results showed that depressive-like behavioral performance and decreased BDNF level were correlated with increased Hcy levels that were detected in 2-month isolated mice. Elevated Hcy induced by high methionine diet mimicked the depressive-like behaviors and BDNF downregulation in the same manner as social isolation, while administration of vitamin B complex supplements to reduce Hcy alleviated the depressive-like behaviors and BDNF reduction in socially isolated mice. Altogether, our results indicated that Hcy played a critical role in social isolation-induced depressive-like behaviors and BDNF reduction, suggesting the possibility of Hcy as a potential therapeutic target and vitamin B intake as a potential value in the prevention of stress-induced depression.

Development and validation of a machine learning-based prognostic risk stratification model for acute ischemic stroke

Acute ischemic stroke (AIS) is a most prevalent cause of serious long-term disability worldwide. Accurate prediction of stroke prognosis is highly valuable for effective intervention and treatment. As such, the present retrospective study aims to provide a reliable machine learning-based model for prognosis prediction in AIS patients. Data from AIS patients were collected retrospectively from the Second Affiliated Hospital of Xuzhou Medical University between August 2017 and July 2019. Independent prognostic factors were identified by univariate and multivariate logistic analysis and used to develop machine learning (ML) models. The ML model performance was assessed by area under the receiver operating characteristic curve (AUC) and radar plot. Shapley Additive explanations (SHAP) values were used to interpret the importance of all features included in the predictive model. A total of 677 AIS patients were included in the present study. Poor prognosis was observed in 209 patients (30.9%). Six variables, including neuron specific enolase (NSE), homocysteine (HCY), S-100β, dysphagia, C-reactive protein (CRP), and anticoagulation were included to establish ML models. Six different ML algorithms were tested, and Random Forest model was selected as the final predictive model with the greatest AUC of 0.908. Moreover, according to SHAP results, NSE impacted the predictive model the most, followed by HCY, S-100β, dysphagia, CRP and anticoagulation. Based on the RF model, an online tool was constructed to predict the prognosis of AIS patients and assist clinicians in optimizing patient treatment. The present study revealed that NSE, HCY, CRP, S-100β, anticoagulation, and dysphagia were important factors for poor prognosis in AIS patients. ML algorithms were used to develop predictive models for predicting the prognosis of AIS patients, with the RF model presenting the optimal performance.

Homocysteine levels in patients with coronary slow flow phenomenon: A meta-analysis

BACKGROUND

With the development of coronary angiography, more and more attention has been paid to coronary slow flow phenomenon (CSFP). Recent studies have found that the correlation between homocysteine (Hcy) levels and CSFP was contradictory, so we conducted this meta-analysis to investigate the correlation.

METHODS

By March 2022, studies that meet the research requirements were identified by searching multiple databases including Embase, Web of Science, and PubMed. We included studies evaluating the correlation between Hcy levels and CSFP. Random or fixed effect meta-analyses were performed according to heterogeneity among included studies. A leave-out method and subgroup analyses were conducted to determine the source of heterogeneity.

RESULTS

Thirteen studies involving 625 CSFP and 550 subjects were included. After pooling data from each study, Hcy levels were higher in the CSFP groups (standard mean difference [SMD], 1.45; 95% CI, 0.94 to 1.96, P < .00001) than in the control group. In the meta-analysis, there was significant heterogeneity (I2 = 93%), which was further explored through leave-out method and and subgroup analyses. Specifically, pooling data from studies with a mean thrombolysis in myocardial infarction (TIMI) frame count ≥ 46 (SMD, 1.31; 95% CI, 1.00 to 1.63, P < .00001) resulted in no heterogeneity (0%), indicating that the TIMI frame count ≥ 46 was the source of heterogeneity.

CONCLUSIONS

Our study found that elevated Hcy levels are strongly associated with CSFP. More importantly, the association was stronger in CSFP patients with mean TIMI frame count ≥ 46.

Thymoquinone reverses homocysteine-induced endothelial dysfunction via inhibition of ER-stress induced oxidative stress pathway.. [DOI: 10.21203/rs.3.rs-2964177/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Hyperhomocysteinemia has been linked to an increased risk of cardiovascular diseases. High levels of homocysteine (Hcy) promote endoplasmic reticulum (ER) stress that can increase reactive oxygen species (ROS), leading to endothelial dysfunction. Thymoquinone (TQ) is the major active ingredient in Nigella sativa seeds volatile oil and is shown to have a cardioprotective effect. However, no study evaluated the effect of TQ against Hcy-induced endothelial dysfunction. Thus, this study aims to investigate the effects and mechanisms of TQ in reversing Hcy-induced endothelial dysfunction. Isolated aorta from male Sprague-Dawley (SD) rats incubated with Hcy (500 µM) and co-treated with or without TQ (0.1 µM, 1 µM, and 10 µM), 20 µM TUDCA, 100 µM Apocynin or 1 mM Tempol in organ bath to study the vascular function. Additionally, human umbilical vein endothelial cells (HUVECs) were incubated with Hcy (10 mM) and various concentrations of TQ (1 and 10 𝜇M), Tempol (100 𝜇M), Apocynin (100 𝜇M), TUDCA (100 𝜇M) or H2O2 (0.25 mM) to evaluate the cell viability by using a phase contrast microscope and dye exclusion assay. Involvement of ER stress pathway, ROS and NO bioavailability were accessed via immunoassay and fluorescent staining respectively. Molecular docking was performed to evaluate the binding affinity of TQ to GRP78. Our results revealed that Hcy impaired endothelium-dependant relaxation in isolated aorta and induced apoptosis in HUVECs. These effects were reversed by TQ, TUDCA, tempol and apocynin. Treatment with TQ (10𝜇M) also reduced ROS level, improved NO bioavailability as well reduced GRP78 and NOX4 protein in HUVECs. Result from the molecular docking study showed that TQ could bind well to GRP78 through hydrogen bond and hydrophobic interaction with the amino acid at GRP78 ATP binding pocket. Taken together, the present results suggest that TQ preserved endothelial function in rat aorta and reduced apoptosis of HUVECs induced by Hcy through the inhibition of ER stress-mediated ROS and eNOS uncoupling.

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.

Urinary Metabolomics for the Prediction of Radiation-Induced Cardiac Dysfunction

Survivors of acute radiation exposures are likely to experience delayed effects that manifest as injury in late-responding organs such as the heart. Noninvasive indicators of radiation-induced cardiac dysfunction are important in the prediction and diagnosis of this disease. In this study, we aimed to identify urinary metabolites indicative of radiation-induced cardiac damage by analyzing previously collected urine samples from a published study. The samples were collected from male and female wild-type (C57BL/6N) and transgenic mice constitutively expressing Activated Protein C (APCHi), a circulating protein with potential cardiac protective properties, that were exposed to 9.5 Gy of γ-rays. We utilized LC-MS-based metabolomics and lipidomics for the analysis of urine samples collected at 24 h, 1 week, 1 month, 3 months, and 6 months post-irradiation. Radiation caused perturbations in the TCA cycle, glycosphingolipid metabolism, fatty acid oxidation, purine catabolism, and amino acid metabolites, which were more prominent in wild-type (WT) mice compared to APCHi mice, suggesting a differential response between the two genotypes. After combining genotypes and sexes, we identified a multi-analyte urinary panel at early post-irradiation time points that predicted heart dysfunction using a logistic regression model with a discovery validation study design. These studies demonstrate the utility of a molecular phenotyping approach to develop a urinary biomarker panel predictive of delayed effects of ionizing radiation. It is important to note that no live mice were used or assessed in this study; instead, we focused solely on analyzing previously collected urine samples.

Homocysteine accelerates hepatocyte autophagy by upregulating TFEB via DNMT3b-mediated DNA hypomethylation

Autophagy plays a critical role in the physiology and pathophysiology of hepatocytes. High level of homocysteine (Hcy) promotes autophagy in hepatocytes, but the underlying mechanism is still unknown. Here, we investigate the relationship between Hcy-induced autophagy level and the expression of nuclear transcription factor EB (TFEB). The results show that Hcy-induced autophagy level is mediated by upregulation of TFEB. Silencing of TFEB decreases the level of autophagy-related protein LC3BII/I and increases p62 expression level in hepatocytes after exposure to Hcy. Moreover, the effect of Hcy on the expression of TFEB is regulated by hypomethylation of the TFEB promoter catalyzed by DNA methyltransferase 3b (DNMT3b). In summary, this study shows that Hcy can activate autophagy by inhibiting DNMT3b-mediated DNA methylation and upregulating TFEB expression. These findings provide another new mechanism for Hcy-induced autophagy in hepatocytes.

The inhibitory effect of vitamin D on myocardial homocysteine levels involves activation of Nrf2-mediated methionine synthase

BACKGROUND

Homocysteine (Hcy) is a synthetic amino acid containing sulfhydryl group, which is an intermediate product of the deep metabolic pathway of methionine and cysteine. The abnormal increase in fasting plasma total Hcy concentration caused by various factors is called hyperhomocysteine (HHcy). HHcy is closely relevant to the occurrence and progression of diverse cardiovascular and cerebrovascular diseases, such as coronary heart disease, hypertension and diabetes, etc. Vitamin D/vitamin D receptor (VDR) pathway is pointed out that prevent cardiovascular disease by reducing serum homocysteine levels. Our research is designed to explore the potential mechanism of vitamin D in the prevention and treatment of HHcy.

METHODS AND RESULTS

The Hcy and 25(OH)D₃ levels in mouse myocardial tissue, serum or myocardial cells were detected using ELISA kits. The expression levels of VDR, Nrf2 and methionine synthase (MTR) were observed using Western blotting, immunohistochemistry and real time polymerase chain reaction (PCR). General information of the mice, including diet, water intake and body weight, was recorded. Vitamin D up-regulated the mRNA and protein expression of Nrf2 and MTR in mouse myocardial tissue and cells. CHIP assay determined that the combination of Nrf2 binding to the S1 site of the MTR promoter in cardiomyocytes using traditional PCR and real time PCR. Dual Luciferase Assay was applied to detect the transcriptional control of Nrf2 on MTR. The up-regulation effect of Nrf2 on MTR was verified by Nrf2 knockout and overexpression in cardiomyocytes. The role of Nrf2 in vitamin D inhibition of Hcy was revealed using Nrf2-knockdown HL-1 cells and Nrf2 heterozygous mice. Western blotting, real time PCR, IHC staining and ELISA showed that Nrf2 deficiency could restrain the increase in MTR expression and the decrease in Hcy level induced by vitamin D. The transcriptional activities of Nrf2/MTR were activated by vitamin D/VDR with a decrease in Hcy.

CONCLUSION

Vitamin D/VDR upregulates MTR in an Nrf2-dependent manner, thereby reducing the risk of HHcy.

Genetic and phenotypic frequency distribution of ACE, ADRB1, AGTR1, CYP2C9*3, CYP2D6*10, CYP3A5*3, NPPA and factors associated with hypertension in Chinese Han hypertensive patients

We analyzed the polymorphisms of 7 antihypertensive drugs-related genes and the factors associated with hypertension in hypertensive patients of Han ethnicity in Qingyang, China. A total of 354 hypertensive patients of Han ethnicity were enrolled from Qingyang, China. The ACE (I/D), ADRB1 (1165G > C), AGTR1 (1166A > C), CYP2C9*3, CYP2D6*10, CYP3A5*3 and NPPA (T2238C) polymorphisms were assessed. Clinical data of patients was also obtained. The influencing factors of hypertension were evaluated. The genotype frequencies of ACE, ADRB1, AGTR1, CYP2C9, CYP3A5 and NPPA loci were in Hardy-Weinberg equilibrium, with mutation frequencies of 39.27%, 74.29%, 6.21%, 4.80%, 72.46% and 0.71%, respectively. CYP2D6 locus was not in Hardy-Weinberg equilibrium. There was no statistical difference in allele frequencies between different genders (P > .05). There was significant difference in the frequencies of ACE (I/D) and NPPA (T2238C) loci among different regions of China (P < .05). Gender, ACE (I/D) and ADRB1 (1165G > C) gene polymorphism, smoking, homocysteine and HDL levels were associated hypertension. The mutation frequencies of ADRB1 (1165G > C) and CYP3A5*3 were high in hypertensive patients of Han ethnicity in Qingyang, suggesting these patients may be more sensitive to beta-blockers and calcium ion antagonists. Meanwhile, hypertension was associated with gender, ACE (I/D) and ADRB1 (1165G > C) gene polymorphisms, smoking, homocysteine and HDL levels.

Consumption of very low-mineral water may threaten cardiovascular health by increasing homocysteine in children

Introduction

Homocysteine (Hcy) is a critical factor for cardiovascular injury, and the elevation of Hcy in children will inevitably increase the risk of cardiovascular disease in adulthood. This study explored the effect of very low-mineral water on children’s Hcy and cardiovascular health.

Materials and methods

This was a retrospective cohort study that recruited two groups of 10–13-year-old children who had consumed direct drinking water (DDW) in school for 4 years. The control group (NW) (119 boys, 110 girls) consumed normal DDW (conductivity 345 μs/cm). The very low-mineral water consumption group (VLW) (223 boys, 208 girls) consumed very low-mineral DDW (conductivity 40.0 μs/cm). Serum Hcy, Hcy metabolites, cofactors of Hcy metabolism, and cardiovascular biomarkers were assessed and standardized by age- and sex-specific Z-scores, and the differences between the two groups were analyzed with independent t-test. The relationships between Hcy metabolism biomarkers and key factors, cardiovascular biomarkers, serum Ca, and mineral intake were analyzed with linear regression.

Results

Compared with the NW group, the VLW group had significantly higher serum Hcy, Apo-B, Apo-B/A1, and oxLDL, and lower serum 1,25,(OH)2D3, vitamin B6 and B12, 5-methyltetrahydrofolate, and Apo-A1. Serum Hcy was positively associated with serum Apo-B and Apo-B/A1, and negatively associated with Ca intake from water and serum 1,25,(OH)2D3.

Conclusion

This study suggested that drinking very low-mineral water may increase Hcy level and oxidative stress, worsen lipid profile, and threaten the cardiovascular system in children. Reducing 1,25,(OH)2D3, and disordering of calcium metabolism might play important roles. This study first established an association between demineralized drinking water and cardiovascular health in children, suggesting a new environmental concern risk to cardiovascular health.

Sodium tanshinone IIA sulfonate protects against hyperhomocysteine-induced vascular endothelial injury via activation of NNMT/SIRT1-mediated NRF2/HO-1 and AKT/MAPKs signaling in human umbilical vascular endothelial cells

Homocysteine (Hcy) is one of the independent risk factors of cardiovascular disease. Sodium tanshinone IIA sulfonate (STS) is a hydrophilic derivate of tanshinone IIA which is the main active constitute of Chinese Materia Medica Salviae Miltiorrhizae Radix et Rhizoma, and exhibits multiple pharmacological activities. However, whether STS could prevent from Hcy-induced endothelial cell injury is unknown. We found that STS dramatically reversed Hcy-induced cell death concentration dependently in human umbilical vascular endothelial cells (HUVECs). STS ameliorated the endothelial cell cycle progression, proliferation and cell migratory function impaired by Hcy, which might be co-related to the inhibition of intracellular oxidative stress and mitochondrial dysfunction. STS also elevated the phosphorylation of AKT and MAPKs and protein expression of sirtuin1 (SIRT1), NRF2 and HO-1 which were suppressed by Hcy. The protective effect of STS against Hcy-induced endothelial cell toxicity was partially attenuated by PI3K, AKT, MEK, ERK, SIRT1, NRF2 and HO-1 inhibitors. Besides, knockdown of SIRT1 by its siRNA dramatically decreased the endothelial protective effect of STS accompanied with suppression of SIRT1, NRF2, HO-1 and phosphorylated AKT. The activation of AKT or NRF2 partially reversed SIRT1-knockdown impaired cyto-protective effect of STS against Hcy-induced cell injury. Furthermore, STS prevented from Hcy-induced intracellular nicotinamide N-methyltransferase (NNMT) reduction along with elevation of intracellular methylnicotinamide (MNA), and MNA enhanced STS protecting against Hcy induced endothelial death. Knockdown of NNMT reduced the protective effect of STS against Hcy induced endothelial cell injury. Collectively, STS presented potent endothelial protective effect against Hcy and the underlying molecular mechanisms were involved in the suppression of intracellular oxidative stress and mitochondria dysfunction by activation of AKT/MAPKs, SIRT1/NRF2/HO-1 and NNMT/MNA signaling pathways.

Using Bayesian networks with Tabu-search algorithm to explore risk factors for hyperhomocysteinemia

Hyperhomocysteinemia (HHcy) is a condition closely associated with cardiovascular and cerebrovascular diseases. Detecting its risk factors and taking some relevant interventions still represent the top priority to lower its prevalence. Yet, in discussing risk factors, Logistic regression model is usually adopted but accompanied by some defects. In this study, a Tabu Search-based BNs was first constructed for HHcy and its risk factors, and the conditional probability between nodes was calculated using Maximum Likelihood Estimation. Besides, we tried to compare its performance with Hill Climbing-based BNs and Logistic regression model in risk factor detection and discuss its prospect in clinical practice. Our study found that Age, sex, α1-microgloblobumin to creatinine ratio, fasting plasma glucose, diet and systolic blood pressure represent direct risk factors for HHcy, and smoking, glycosylated hemoglobin and BMI constitute indirect risk factors for HHcy. Besides, the performance of Tabu Search-based BNs is better than Hill Climbing-based BNs. Accordingly, BNs with Tabu Search algorithm could be a supplement for Logistic regression, allowing for exploring the complex network relationship and the overall linkage between HHcy and its risk factors. Besides, Bayesian reasoning allows for risk prediction of HHcy, which is more reasonable in clinical practice and thus should be promoted.

Vitamin B12, Folate, Homocysteine, Inflammatory Mediators (Interleukin-6, Tumor Necrosis Factor-α and C-Reactive Protein) Levels in Adolescents with Anxiety or Depressive Symptoms

Purpose

To evaluate the prevalence of abnormal vitamin B12, folate, total homocysteine (tHcy), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP) levels, to analyze the relationship between these parameters and the severity of anxiety or depressive symptoms, and to explore the possible factors associated with abnormal levels of these parameters in adolescents with anxiety or depressive symptoms.

Methods

Adolescent (aged 12-18 years) outpatients with anxiety or depressive symptoms were recruited. The patient health questionnaire-9 and generalized anxiety disorder scale-7 were used to measure the severity of depression and anxiety. Serum vitamin B12, folate, tHcy, IL-6, TNF-α, and CRP levels were determined.

Results

128 subjects were recruited. The prevalence of vitamin B12 and folate deficiency, tHcy, TNF-α, IL-6, and CRP elevation was 8.6%, 10.2%, 25.8%, 14.8%, 21.9%, and 10.2%, respectively, in adolescents with anxiety or depressive symptoms. Lower vitamin B12 levels were correlated with a higher risk of severe anxiety and depressive symptoms. The severity of some symptoms of anxiety or depression were weakly correlated with vitamin B12, folate, tHcy, IL-6, and CRP levels. Vitamin B12, folate, and tHcy levels were not associated with inflammatory mediators. Vitamin B12 deficiency was associated with older age and higher tHcy levels. Folate deficiency was associated with elevated tHcy. Elevated tHcy was associated with lower vitamin B12 and folate levels. IL-6 elevation was associated with elevated CRP and TNF-α. CRP elevation was associated with older age, higher BMI, and current drinking.

Conclusion

Lower vitamin B12 levels were correlated with a higher risk of severe anxiety or depressive symptoms. Weak correlations were observed between the severity of some symptoms of anxiety or depression and vitamin B12, folate, tHcy, IL-6, and CRP levels. Vitamin B12, folate, and tHcy levels were related to each other. IL-6 elevation was associated with elevated CRP and TNF-α. CRP elevation was associated with older age, higher BMI, and current drinking.

Relationship Between Plasma Homocysteine and Bone Density, Lean Mass, Muscle Strength and Physical Function in 1480 Middle-Aged and Older Adults: Data from NHANES

Hyperhomocysteinemia induces oxidative stress and chronic inflammation (both of which are catabolic to bone and muscle); thus, we examined the association between homocysteine and body composition and physical function in middle-aged and older adults. Data from the National Health and Nutrition Examination Survey was used to build regression models. Plasma homocysteine (fluorescence immunoassay) was used as the exposure and bone mineral density (BMD; dual-energy X-ray absorptiometry; DXA), lean mass (DXA), knee extensor strength (isokinetic dynamometer; newtons) and gait speed (m/s) were used as outcomes. Regression models were adjusted for confounders (age, sex, race/Hispanic origin, height, fat mass %, physical activity, smoking status, alcohol intakes, cardiovascular disease, diabetes, cancer and vitamin B12). All models accounted for complex survey design by using sampling weights provided by NHANES. 1480 adults (median age: 64 years [IQR: 56, 73]; 50.3% men) were included. In multivariable models, homocysteine was inversely associated with knee extensor strength (β = 0.98, 95% CI 0.96, 0.99, p = 0.012) and gait speed (β = 0.85, 95% CI 0.78, 0.94, p = 0.003) and borderline inversely associated with femur BMD (β = 0.84, 95% CI 0.69, 1.03, p = 0.086). In the sub-group analysis of older adults (≥ 65 years), homocysteine was inversely associated with gait speed and femur BMD (p < 0.05) and the slope for knee extensor strength and whole-body BMD were in the same direction. No significant associations were observed between homocysteine and total or appendicular lean mass in the full or sub-group analysis. We found inverse associations between plasma homocysteine and muscle strength/physical function, and borderline significant inverse associations for femur BMD.

Increased serum homocysteine in first episode and drug-naïve individuals with schizophrenia: sex differences and correlations with clinical symptoms

BACKGROUND

Accumulating evidence shows that homocysteine (Hcy) is implicated in the pathophysiology of schizophrenia, and plays an important role in clinical characteristics. This study evaluated the relationships between Hcy levels and clinical features in first-episode, Chinese Han, drug-naïve (FEDN) patients with schizophrenia.

METHODS

FEDN individuals (119 with schizophrenia and 81 healthy controls matched for age, sex, education, and body mass index (BMI)) were enrolled. The serum Hcy levels were determined by enzyme cycle assay experiments. Severities of clinical symptoms were rated on the Positive and Negative Syndrome Scale (PANSS).

RESULTS

FEDN individuals with schizophrenia had higher Hcy levels compared with healthy controls (F = 46.865, P < 0.001). Correlation analysis and multiple stepwise regression analyses showed that serum Hcy levels in FEDN schizophrenia individuals were positively correlated with PANSS general psychopathology subscale (r = 0.294, P = 0.001) and PANSS total score (r = 0.273, P = 0.003). No significant association was found between Hcy and age, BMI, PANSS positive subscale, and the PANSS negative subscale (all, P > 0.05). Male individuals had significantly higher serum Hcy levels than female individuals (F = 7.717, P = 0.006) after controlling for confounding factors (F = 0.759, P = 0.011).

CONCLUSIONS

Serum Hcy levels were increased in FEDN individuals with schizophrenia, and Hcy levels may be involved in pathophysiological mechanisms. Sex differences in Hcy levels were observed, with higher levels in male FEDN individuals compared to females.

Relationship between morning peak phenomenon and early renal injury NGAL in H-type hypertension

PURPOSE

To investigate the relationship between morning blood pressure surge (MBPS) and neutrophilgelatinase associated lipocalin (NGAL) in patients with H-type hypertension.

MATERIALS AND METHODS

A total of 224 patients with diagnosed H-type hypertension [homocysteine (Hcy)≧10umol/L] were selected and underwent 24-hour ambulatory blood pressure monitoring (ABPM). In the morning peak group (115 cases), NGAL and serum cystatin C levels, β2-microglobulin levels were detected in each group, and general biochemical indicators were also detected.

RESULTS

There was no significant difference in the course of hypertension, age, blood glucose, blood lipids, Hcy, BUN, Cr, and UA between the two groups (p > 0.05). CysC, β2-MG were higher than those in the nonmorning peak group, and the difference was statistically significant (p < 0.05).; Pearson correlation analysis showed that NGAL was moderately and highly correlated with CysC, systolic blood pressure morning peak, β2-MG, and high (p < 0.05), low-density lipoprotein (LDL-C), and Hcy were lowly correlated (p < 0.05).) and morning peak diastolic blood pressure (p > 0.05); multiple linear stepwise regression analysis indicated that morning peak systolic blood pressure, CysC,β2-MG, and FBG were the risk factors for NGAL.

CONCLUSION

The morning peak of systolic blood pressure in H-type hypertension is an important factor causing kidney injury. Paying attention to the ambulatory blood pressure monitoring and the control of morning peak blood pressure in patients with H-type hypertension, and early screening of NGAL has important clinical significance for the early prevention and treatment of renal injury in patients with H-type hypertension. PLAIN LANGUAGE SUMMARYThe morning peak of blood pressure is closely related to target organ damage.There are few studies on the relationship between morning peak phenomenon and renal damage in patients with H-type hypertension at home and abroad.We investigated the relationship between MBPS and NGAL in H-type hypertensive patients with BUN, Cr and UA in the normal range to provide a clinical basis for early renal protection in hypertensive patients.

Mendelian randomization as a tool to gain insights into the mosaic causes of autoimmune diseases

Autoimmune diseases (ADs) are a broad range of disorders which are characterized by long-term inflammation and tissue damage arising from an immune response against one's own tissues. It is now widely accepted that the causes of ADs include environmental factors, genetic susceptibility and immune dysregulation. However, the exact etiology of ADs has not been fully elucidated to date. Because observational studies are plagued by confounding factors and reverse causality, no firm conclusions can be drawn about the etiology of ADs. Over the years, Mendelian randomization (MR) analysis has come into focus, offering unique perspectives and insights into the etiology of ADs and promising the discovery of potential therapeutic interventions. In MR analysis, genetic variation (alleles are randomly dispensed during meiosis, usually irrespective of environmental or lifestyle factors) is used instead of modifiable exposure to explore the link between exposure factors and disease or other outcomes. Therefore, MR analysis can provide a valuable method for exploring the causal relationship between different risk factors and ADs when its inherent assumptions and limitations are fully considered. This review summarized the recent findings of MR in major ADs, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), multiple sclerosis (MS), and type 1 diabetes mellitus (T1DM), focused on the effects of different risk factors on ADs risks. In addition, we also discussed the opportunities and challenges of MR methods in ADs research.

The association between serum albumin levels and related metabolic factors and atrial fibrillation: A retrospective study

The association between serum albumin (ALB) and cardiovascular events has been well established, but the relationship with atrial fibrillation (AF) remains controversial. This study aims to evaluate the association between ALB and AF in a Chinese population. We reviewed the medical records of 2000 hospitalized patients, 1000 patients with AF were included in the AF group, and 1000 age- and sex-matched patients with sinus rhythm and no history of AF were included in the control group. The T test or chi-square test were conducted to analyze clinical baseline data. Logistic regression analysis was conducted to assess the relationship between AF and ALB. The interrelationships of ALB were analyzed by Pearson correlation analyses. The appropriate cutoff value of ALB for AF was analyzed by receiver operating characteristic curves. ALB levels were lower in the AF group than in the control group (P < .05). After multivariable adjustment, ALB was independently negatively associated with AF (odds ratio = 0.935, 95% confidence interval: 0.905-0.965, P < .05). ALB levels were positively correlated with serum globulin, total cholesterol, triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, serum apolipoprotein A1, and serum apolipoprotein B levels (P < .05), but negatively correlated with serum creatinine levels (P < .05). The optimal cutoff value of ALB for predicting AF was 37.25 g/L, the sensitivity was 78.0%, and the specificity was 4.6%. Low ALB level is independently associated with AF. Since the current study design cannot establish causalities, further prospective cohort studies are needed to determine this finding.

HOMOCYSTEINE AND CARDIOVASCULAR DISEASE - A CURRENT REVIEW

Cardiovascular diseases remain the leading cause of death worldwide for the past 20 years. Of these, ischemic heart disease has the highest mortality rate. In over 98% of cases it is caused by atherosclerosis of the coronary arteries. Homocysteine is an amino acid, containing a sulfhydryl group, which is formed as a result of the metabolism of the amino acids methionine and cysteine, which is supplied with protein-containing foods. A small amount of it is necessary for the proper functioning of the body, however, an increased concentration in blood plasma, which hyperhomocysteinemia, negatively affects blood vessels leading to the development of atherosclerosis and thrombotic com¬plications. The adverse effect on blood vessels results from various mechanisms, such as: excessive activation of Toll-like 4 receptor, activation N-methyl-d-aspartate receptors, increased production of reactive oxygen species, and impairment of nitric oxide synthesis. Elevated levels of reactive oxygen species are associated with increased expression of proinflammatory cytokines such as IL-1β, IL-6, TNF-α (tumor necrosis tumor necrosis factor), MCP-1 and intracellular adhesion molecule-1. Another factor contributing to hyperhomocysteinemia is mutation of the MTHFR gene, which in normal conditions is responsible for maintaining homocysteine levels within the normal range. People with MTHFR mutation are more prone to develop atherosclerosis and the following complications: myocardial infarction, stroke, thrombotic episodes and coronary artery disease. The aim of this paper is to present evidence supporting the role of homocysteine in the development of many cardiovascular diseases.

Magnetic field therapy enhances muscle mitochondrial bioenergetics and attenuates systemic ceramide levels following ACL reconstruction: Southeast Asian randomized-controlled pilot trial

Background

Metabolic disruption commonly follows Anterior Cruciate Ligament Reconstruction (ACLR) surgery. Brief exposure to low amplitude and frequency pulsed electromagnetic fields (PEMFs) has been shown to promote in vitro and in vivo murine myogeneses via the activation of a calcium–mitochondrial axis conferring systemic metabolic adaptations. This randomized-controlled pilot trial sought to detect local changes in muscle structure and function using MRI, and systemic changes in metabolism using plasma biomarker analyses resulting from ACLR, with or without accompanying PEMF therapy.

Methods

20 patients requiring ACLR were randomized into two groups either undergoing PEMF or sham exposure for 16 weeks following surgery. The operated thighs of 10 patients were exposed weekly to PEMFs (1 ​mT for 10 ​min) for 4 months following surgery. Another 10 patients were subjected to sham exposure and served as controls to allow assessment of the metabolic repercussions of ACLR and PEMF therapy. Blood samples were collected prior to surgery and at 16 weeks for plasma analyses. Magnetic resonance data were acquired at 1 and 16 weeks post-surgery using a Siemens 3T Tim Trio system. Phosphorus (³¹P) Magnetic Resonance Spectroscopy (MRS) was utilized to monitor changes in high-energy phosphate metabolism (inorganic phosphate (P_i), adenosine triphosphate (ATP) and phosphocreatine (PCr)) as well as markers of membrane synthesis and breakdown (phosphomonoesters (PME) and phosphodiester (PDE)). Quantitative Magnetization Transfer (qMT) imaging was used to elucidate changes in the underlying tissue structure, with T1-weighted and 2-point Dixon imaging used to calculate muscle volumes and muscle fat content.

Results

Improvements in markers of high-energy phosphate metabolism including reductions in ΔP_i/ATP, P_i/PCr and (P_i ​+ ​PCr)/ATP, and membrane kinetics, including reductions in PDE/ATP were detected in the PEMF-treated cohort relative to the control cohort at study termination. These were associated with reductions in the plasma levels of certain ceramides and lysophosphatidylcholine species. The plasma levels of biomarkers predictive of muscle regeneration and degeneration, including osteopontin and TNNT1, respectively, were improved, whilst changes in follistatin failed to achieve statistical significance. Liquid chromatography with tandem mass spectrometry revealed reductions in small molecule biomarkers of metabolic disruption, including cysteine, homocysteine, and methionine in the PEMF-treated cohort relative to the control cohort at study termination. Differences in measurements of force, muscle and fat volumes did not achieve statistical significance between the cohorts after 16 weeks post-ACLR.

Conclusion

The detected changes suggest improvements in systemic metabolism in the post-surgical PEMF-treated cohort that accords with previous preclinical murine studies. PEMF-based therapies may potentially serve as a manner to ameliorate post-surgery metabolic disruptions and warrant future examination in more adequately powered clinical trials.

The Translational Potential of this Article

Some degree of physical immobilisation must inevitably follow orthopaedic surgical intervention. The clinical paradox of such a scenario is that the regenerative potential of the muscle mitochondrial pool is silenced. The unmet need was hence a manner to maintain mitochondrial activation when movement is restricted and without producing potentially damaging mechanical stress. PEMF-based therapies may satisfy the requirement of non-invasively activating the requisite mitochondrial respiration when mobility is restricted for improved metabolic and regenerative recovery.

Positive Effect of a Pea-Clam Two-Peptide Composite on Hypertension and Organ Protection in Spontaneously Hypertensive Rats

In the present study, we prepared pea peptides with high angiotensin-converting enzyme (ACE) inhibitory activity in vitro using an enzymatic hydrolysis of pea protein and compounded them with clam peptides to obtain a pea-clam double peptide. The effects of the two-peptide composite and pea peptides on hypertension and the damage-repair of corresponding organs were studied in spontaneously hypertensive rats (SHRs). We found that both pea peptides and the two-peptide composite significantly reduced the blood pressure upon a single or long-term intragastric administration, with the two-peptide composite being more effective. Mechanistically, we found that the two-peptide composite could regulate the renal renin-angiotensin system (RAS), rebalance gut microbial dysbiosis, decrease renal and myocardial fibrosis, and improve renal and cardiac function and vascular remodeling. Additionally, hippocampal lesions caused by hypertension were also eliminated after two-peptide composite administration. Our research provides a scientific basis for the use of this two-peptide composite as a safe antihypertension ingredient in functional foods.

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.

Beneficial effects of vitamin B12 treatment in pediatric patients diagnosed with vitamin B12 deficiency regarding total-native thiol, oxidative stress, and mononuclear leukocyte DNA damage

Vitamin B₁₂ is involved in biochemical metabolic pathways. B₁₂ deficiency is common in childhood when the need for the vitamin increases and growth and development occur. Various hematological, neurological, psychiatric, and gastrointestinal disorders are observed in its deficiency. In addition, B₁₂ deficiency is associated with oxidative stress and DNA damage. Therefore, the aim of our study is to evaluate oxidative stress, thiol/disulfide homeostasis, and DNA damage pre and post-treatment in children diagnosed with B₁₂ deficiency. A total of 40 children with B₁₂ deficiency were included in the study after the consent form was approved. Blood was drawn from children pre and posttreatment. Hemoglobin (HGB), hematocrit (HCT), and red blood cells (RBC) were measured by autoanalyzer; total antioxidant status (TAS), total oxidant status (TOS), total thiol (TT), and native thiol (NT) were measured by the photometric method, and DNA damage was analyzed by the comet assay method. Oxidative stress index (OSI) and disulfide (DIS) values were calculated. As a result of the experiments, HGB, HCT, and RBC increased with treatment. While TAS, TT, and NT as antioxidant parameters increased; TOS, OSI, and DIS decreased with treatment compared to pretreatment. DNA damage was also found to decrease with treatment. Additionally, these data were statistically significant (p < 0.001). It was found that oxidative stress and DNA damage decreased with oral B₁₂ treatment in children with B₁₂ deficiency, and clinical parameters were also improved.