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Metabolic pathways of folic acid, vitamin B12, and homocysteine and their relationship with Helicobacter pylori infection. CH3, methyl; FA, folic acid; Hp, Helicobacter pylori; MS, methionine synthase; MTHFR, methylene tetrahydrofolate reductase; THF, tetrahydrofolate; VB12, vitamin B12.
Source publication
Background
Previous studies have shown that Helicobacter pylori (Hp) infection is associated with erectile dysfunction (ED), but the mechanism is unclear.
Aim
To assess the relationship between ED and Hp, folic acid (FA), vitamin B12 (B12), and homocysteine (HCY).
Methods
This study included 84 patients with ED and 42 healthy men. We adopted an I...
Contexts in source publication
Context 1
... This study is the first to link Hp infection, FA, B12, and HCY and further explain the relationship between these indicators and the underlying pathologic mechanisms that jointly cause ED. Given the results of this study, we hypothesized that the absorption disorder of FA and B12 caused by Hp infection contributed to the metabolic disorder of HCY, which caused HHcy and then damaged vascular endothelial function, thus leading to the occurrence of ED (Figure 2). Several studies have shown that Hp infection affects the absorption of various trace elements, especially B12 and FA, by disrupting gastric secretion and attenuating acidification functions. ...
Context 2
... Our study also revealed that patients with ED had higher Hp-IgG titer levels and lower FA and B12 levels, which were significantly negatively correlated with Hp-IgG titer. The specific mechanism of the impairment of FA and B12 absorption caused by Hp infection is still unclear, and there are several possibilities, as shown in Figure 2. First, the Hp-induced decrease in gastric acid secretion may not only lead to difficulties with the critical splitting of B12 and FA from food binders but also interfere with the transfer of food cobalamin to R-binders. ...
Context 3
... Our study revealed that one of the mechanisms of penile vascular endothelial injury may be related to HCY metabolism disorder caused by low levels of FA and B12 caused by Hp infection. Previous studies have shown that eNOS activation and expression are inhibited and eNOS decoupling is promoted in patients with HHcy, which can cause endothelial dysfunction and lead to ED. 34 As shown in Figure 2, B12 and FA are important cofactors in the remethylation of HCY to methionine by methylene tetrahydrofolate reductase. FA and B12 deficiency could hinder HCY metabolism, leading to HCY accumulation and causing HHcy, which is consistent with our findings. ...
Citations
... It stimulates the production of cyclic guanosine sapogenins by activating soluble guanylate cyclase, leading to elevated intracorporeal pressure, vasodilation, and erection [56]. In addition, Elevated levels of homocysteine can hinder the activation and expression of Endothelial Nitric Oxide Synthase (eNOS), promote eNOS uncoupling, and boost the production of oxygen free radicals, resulting in endothelial dysfunction [57]. Furthermore, this study discovered that inflammation also mediated the relationship between MET-VF and erectile dysfunction. ...
Introduction
Although previous studies have linked obesity and erectile dysfunction, the novel surrogate indicators of adipose accumulation are more essential and dependable factors to consider. Therefore, the primary objective of the current investigation was to examine and clarify the association between metabolic score for visceral fat (METS-VF) and erectile dysfunction.
Methods
Firstly, multivariate logistic regression analysis, smoothed curve fitting, and threshold effect analysis were employed to investigate the association between METS-VF and erectile dysfunction. Mediation analysis was also performed to evaluate the mediating role of homocysteine and inflammation. After that, subgroup analysis was carried out to examine the stability of the correlation of METS-VF with erectile dysfunction in various population settings. Furthermore, the area under the receiver operating characteristic (ROC) curve and eXtreme Gradient Boosting (XGBoost) algorithm were utilized to assess the capability of identifying METS-VF in comparison to the other four obesity-related indicators in identifying erectile dysfunction.
Results
After adjusting for all confounding factors, METS-VF was strongly and favourablely correlated with erectile dysfunction. With each additional unit rise in METS-VF, the prevalence of erectile dysfunction increased by 141%. A J-shaped relationship between METS-VF and erectile dysfunction was discovered through smoothed curve fitting. Marital status, physical activity, and smoking status can potentially modify this association. This finding of the ROC curve suggests that METS-VF had a powerful identifying capacity for erectile dysfunction (AUC = 0.7351). Homocysteine and inflammation mediated 4.24% and 2.81%, respectively.
Conclusion
The findings of the current investigation suggest that METS-VF can be considered a dependable identifying indicator of erectile dysfunction.
... To investigate the correlation between LDL-C/HDL-C and ED severity, we combined mild ED with normal controls and moderate ED with severe ED. Concurrently, ALT, GLU, HCY, and UA are considered potential risk factors for the incidence of ED [10,[30][31][32]. To control for confounding variables, these factors were adjusted in our Endocrine multivariate model. ...
... In observational studies, biases caused by potential confounders could be one of the reasons for discrepancies between observational study results and MR analyses. Research has demonstrated that non-lipid parameters such as UA, GLU, HCY and ALT are also independent risk factors for ED [10,[30][31][32]. To mitigate the impact of these confounding biases, we employed multivariate logistic regression analyses to evaluate the independent risk factors for the severity of ED, incorporating various confounders into different models to assess the impact of lipid parameters on ED in young individuals. ...
Purpose
Lipid parameters have been shown to have significant predictive value for cardiovascular disease, but few studies have evaluated their correlation with erectile dysfunction (ED) in young men.
Methods
The case-control study encompassed 186 young ED patients (ages 20–40) and 186 healthy controls. Lipid parameters, including total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), TC/HDL ratio, TG/HDL ratio, and LDL-C/HDL-C ratio, were assessed in all participants. The International Index of Erectile Function (IIEF-5) scores were collected for all participants to evaluate erectile status. Multivariate logistic regression analysis was utilized to appraise the association of lipid-related parameters with ED. Single-nucleotide polymorphisms (SNPs) significantly correlated with lipid parameters (TC, TG, LDL-C, HDL-C) were selected from genome-wide association studies (GWAS) as instrumental variables (IV) (P < 5.0 × 10⁻⁸). Summary data for ED was gathered from a GWAS with a sample size of (n = 17,353 cases/28,210 controls). The inverse variance weighted (IVW) method was employed as the primary mendelian randomization (MR) analysis method to assess causal effects. Causal estimates were represented as odds ratios (OR) with 95% confidence intervals (CI).
Results
Results from the case-control study revealed that, when compared with the control group, levels of LDL-C, TG, UA, LDL-C/HDL-C, TG/HDL-C, and TC/HDL-C in the ED group were significantly elevated (P < 0.01), while HDL-C was significantly decreased (P < 0.01) in the ED group. Multivariate logistic regression analysis indicated LDL-C/HDL-C as a risk factor for both the incidence and severity of ED (P < 0.001). Two-sample MR analysis demonstrated no significant causal correlation between lipid parameters—LDL-C (OR, 0.98, 95% CI, 0.88–1.08, P = 0.616), HDL-C (OR, 1.07, 95% CI: 0.96–1.19, P = 0.249), TC (OR, 1.07, 95% CI, 0.96–1.18, P = 0.208), TG (OR, 0.98, 95% CI, 0.80–1.13, P = 0.579) —and an increased risk of ED (all P > 0.05).
Conclusions
The case-control analysis ascertained a significant association between LDL-C, HDL-C, LDL-C/HDL-C, and ED and its severity. However, results from the MR study do not support a causal role of lipid parameters in ED.
