Lowering homocysteine decreases levels and expression of VEGF(165) and endostatin

A machine learning algorithm for peripheral artery disease prognosis using biomarker data

Peripheral artery disease (PAD) biomarkers have been studied in isolation; however, an algorithm that considers a protein panel to inform PAD prognosis may improve predictive accuracy. Biomarker-based prediction models were developed and evaluated using a model development (n = 270) and prospective validation cohort (n = 277). Plasma concentrations of 37 proteins were measured at baseline and the patients were followed for 2 years. The primary outcome was 2-year major adverse limb event (MALE; composite of vascular intervention or major amputation). Of the 37 proteins tested, 6 were differentially expressed in patients with vs. without PAD (ADAMTS13, ICAM-1, ANGPTL3, Alpha 1-microglobulin, GDF15, and endostatin). Using 10-fold cross-validation, we developed a random forest machine learning model that accurately predicts 2-year MALE in a prospective validation cohort of PAD patients using a 6-protein panel (AUROC 0.84). This algorithm can support PAD risk stratification, informing clinical decisions on further vascular evaluation and management.

Differences of Angiogenesis Factors in Tumor and Diabetes Mellitus

Angiogenesis, as a process occurring under the regulation of a variety of factors, is one of the important ways of vascular development. It coexists in a variety of pathological and physiological processes. Now a large number of studies have proved that tumor growth, metastasis, and various vascular complications of diabetes are closely related to angiogenesis, and an increasing number of studies have shown that there are many common factors between the two. But angiogenesis is the opposite of the two: it is enhanced in tumors and suppressed in diabetes. Therefore, this review discusses the causes of the phenomenon from the expression of various factors affecting angiogenesis in these two diseases and their effects on angiogenesis in the relevant microenvironment, as well as the application status of these factors or cells as therapeutic targets in the treatment of these two diseases.

Folic acid ameliorates homocysteine-induced angiogenesis and portosystemic collaterals in cirrhotic rats

INTRODUCTION AND OBJECTIVES

Liver cirrhosis is characterized by increased intrahepatic resistance, splanchnic vasodilation/angiogenesis, and formation of portosystemic collateral vessels. Collaterals can cause lethal complications such as gastroesophageal variceal hemorrhage. Homocysteine is linked to vascular dysfunction and angiogenesis and higher levels have been reported in cirrhotic patients. It is also known that folic acid supplementation reverses the effects of homocysteine. However, the treatment effect in cirrhosis has yet to be investigated.

MATERIAL AND METHODS

Liver cirrhosis was induced in Sprague-Dawley rats with common bile duct ligation (CBDL). The CBDL rats randomly received (1) vehicle; (2) dl-homocysteine thiolactone (1g/kg/day); (3) dl-homocysteine thiolactone plus folic acid (100mg/kg/day); or (4) folic acid. On the 29th day, hemodynamic parameters, liver and renal biochemistry, protein expressions of proangiogenic factors, mesenteric vascular density and portosystemic shunting were evaluated.

RESULTS

In the cirrhotic rats, homocysteine increased mesenteric vascular density and the severity of shunting. It also up-regulated the protein expressions of mesenteric vascular endothelial growth factor (VEGF) and phosphorylated-endothelial nitric oxide synthase (p-eNOS). These effects were reversed by folic acid treatment (P<0.05).

CONCLUSION

Folic acid ameliorated the adverse effects of homocysteine in the cirrhotic rats, which may be related to down-regulation of the VEGF-NO signaling pathway.

Improving diabetic and hypertensive retinopathy with a medical food containing L-methylfolate: a preliminary report

Background

Homocysteine and vitamin D may play a role in the development of diabetic and hypertensive retinopathy in patients with diabetes mellitus (DM) and hypertension. Supplementing food with L-methylfolate and vitamin D theoretically may improve diabetic and hypertensive retinopathy, however, the outcome of these nutritional approaches has not been fully examined. A retrospective case review was done of cases of retinopathy reversal in patients on Ocufolin™ and a similar nonprescription multivitamin, Eyefolate™. In this study, they were administered L-methylfolate (2.7 mg and 3.0 mg, respectively) and vitamin D3 (4500 IU each). These dosages are significantly above the RDA but well below levels associated with toxicity.

Case presentation

Seven patients had nonproliferative diabetic retinopathy (NPDR) and some of them had hypertension. One patient had only hypertensive retinopathy. All patients were instructed to take Ocufolin™ medical food as a food supplement. Baseline genetic testing for MTHFR polymorphisms was conducted. Fundus photography was used to document the fundus condition of the enrolled eyes in 8 NPDR patients at the initial and follow-up visits. Microaneurysms (MA) and exudates were observed to be improved in some trial patients. All subjects had one or more MTHFR polymorphisms. All had diabetic retinopathy, hypertensive retinopathy, or both. MAs were resolved, and exudates were decreased in 8/8 cases after taking the medical food. Retinal edema was found in 2/8 cases and improved or resolved in both cases after taking the medical food or the supplement. The best corrected visual activity was stable or improved in 8/8 cases.

Conclusion

We report a series of diabetic and hypertensive retinopathy cases with MTHFR polymorphisms and the improvement of retinal microvasculature (mainly MAs) in serial fundus photography after taking a medical food or supplement containing L-methylfolate and vitamin D. It appears that the use of nutritional supplements and medical foods containing L-methylfolate and vitamin D may be effective in facilitating the improvement of diabetic and hypertensive retinopathy.

Homocysteine inhibits angiogenesis through cytoskeleton remodeling

Homocysteine (Hcy) is an intermediate non-diet amino acid connecting methionine and folate cycles. Elevated total Hcy level in blood, denoted as hyperhomocysteinemia, has emerged as a prevalent and strong risk factor for multiple diseases including atherosclerotic vascular disease in coronary, cerebral, and peripheral vessels. Its detrimental effect on vascular system implies the potential application as an inhibitor of angiogenesis. However, the detailed mechanism is unveiled. Inhibitory effect of Hcy was assessed on vascular endothelial growth factor (VEGF) induced cell proliferation and migration with endothelial cell (EC) culture system. Its effect on angiogenesis was further examined in vitro and in vivo After Hcy treatment, key angiogenic factors were measured by RT-qPCR. Cellular skeletal structure was also evaluated by actin stress fiber staining. VEGF-induced human umbilical vein EC (HUVEC) proliferation and migration were dramatically down-regulated by Hcy in a dose-responsive manner. Hcy treatment significantly inhibited the VEGF-induced angiogenesis in vitro by tube formation assay and chick chorioallantoic membrane (CAM) vessel formation in vivo Key angiogenic factors like VEGFR1/2 and angiopoietin (Ang)1/2 were substantially reduced by Hcy in HUVEC- and VEGF-induced actin stress fiber cytoskeletal structure was abolished. We demonstrated that Hcy could inhibit angiogenesis by targetting key angiogenic factor and disruption of actin cytoskeleton which is crucial for cell migration.

Methionine-supplemented diet affects the expression of cardiovascular disease-related genes and increases inflammatory cytokines in mice heart and liver

Some important environmental factors that influence the development of cardiovascular diseases (CVD) include tobacco, excess alcohol, and unhealthy diet. Methionine obtained from the diet participates in the synthesis of DNA, proteins, lipids and affects homocysteine levels, which is associated with the elevated risk for CVD development. Therefore, the aim of this study was to investigate the manner in which dietary methionine might affect cellular mechanisms underlying CVD occurrence. Swiss albino mice were fed either control (0.3% DL-methionine), methionine-supplemented (2% DL-methionine), or a methionine-deprived diet (0% DL-methionine) over a 10-week period. The parameters measured included plasma homocysteine concentrations, oxidative stress by reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio, levels of inflammatory cytokines IL-1ß, TNF-α, and IL-6, as well as expression of genes associated with CVD. The levels of apolipoprotein A5 (APOA5), a regulator of plasma triglycerides, were measured. The methionine-supplemented diet increased oxidative stress by lowering the GSH/GSSG ratio in heart tissues and decreased expression of the genes Apob, Ctgf, Serpinb2, Spp1, Il1b, and Sell, but elevated expression of Thbs4, Tgfb2, Ccr1, and Vegfa. Methionine-deprived diet reduced expression of Col3a1, Cdh5, Fabp3, Bax, and Hbegf and increased expression of Sell, Ccl5, Itga2, Birc3, Msr1, Bcl2a1a, Il1r2, and Selp. Methionine-deprived diet exerted pro-inflammatory consequences as evidenced by elevated levels of cytokines IL-1ß, TNF-α, and IL-6 noted in liver. Methionine-supplemented diet increased hepatic IL-6 and cardiac TNF-α. Both methionine supplementation and deprivation lowered hepatic levels of APOA5. In conclusion, data demonstrated that a methionine-supplemented diet modulated important biological processes associated with high risk of CVD development.

Impact of SHMT1 polymorphism on the clinical outcome of patients with metastatic colorectal cancer treated with first-line FOLFIRI+bevacizumab

The impact of thymidylate synthase (TYMS), methylenetetrahydrofolate reductase (MTHFR), and serine hydroxymethyltransferase 1 (SHMT1) gene polymorphisms and that of dihydropyrimidine dehydrogenase (DPD) enzyme activity, serum total homocysteine level, and estimated serum creatinine clearance on first-line 5-fluorouracil, leucovorin, irinotecan, and bevacizumab (FOLFIRI+bevacizumab) regimen efficacy in metastatic colorectal cancer patients was investigated. DNA was extracted from peripheral blood mononuclear cells. Genotyping was performed for TYMS 5'UTR variable number tandem repeat, TYMS 3'UTR ins/del, MTHFR C677T, and SHMT1 C1420T polymorphisms. The DPD activity of peripheral blood mononuclear cells was also determined. The univariate and multivariate analyses demonstrated that the SHMT1 1420T allele was associated with better response (P=0.025) and longer progression-free survival (PFS) (P=0.00004) and overall survival (OS) (P=0.034). Grade ≥2 hypertension was also an independent prognostic factor of longer progression-free survival and OS. Bevacizumab-related hypertension might be a predictive marker of treatment efficacy (P=0.0002 for OS) in the case of wild (CC) SHMT1 1420 genotypes only.

Association Between VEGF Polymorphisms and Homocysteine Levels in Patients With Ischemic Stroke and Silent Brain Infarction

Background and Purpose—

Vascular endothelial growth factor (VEGF) plays a role in atherosclerosis-related diseases such as cerebrovascular or cardiovascular diseases. However, the effect of VEGF -2578C>A, -1154G>A, -634G>C, and 936C>T polymorphisms on the susceptibility to stroke and silent brain infarction has not been reported.

Methods—

Using polymerase chain reaction-amplified DNA, VEGF polymorphisms were analyzed in 615 patients with ischemic stroke, 376 patients with silent brain infarction, and 494 control subjects.

Results—

The AA and CC+CA ( C allele bearing) genotype frequencies of the -2578C>A polymorphism and the CT+TT ( T allele-bearing) genotype frequency of the 936C>T polymorphism were significantly different between the stroke and control groups (false discovery rate-adjusted probability values of 0.016, 0.044, and 0.044, respectively). When stratified by the size of the occluded vessel, the VEGF polymorphisms were associated with patients with multiple small-artery occlusions. Several haplotypes of the VEGF polymorphisms were significantly different between the control and stroke groups. With respect to silent brain infarction, the difference in the frequency of the -634G>C polymorphism between the GC+CC ( C allele-bearing) genotype and the controls was marginally significant (false discovery rate-adjusted probability value of 0.056). On the other hand, the -634G>C and 936C>T polymorphisms were associated with plasma homocysteine levels of patients with multiple or single small-artery occlusions, respectively.

Conclusions—

This study suggests that VEGF polymorphisms and haplotypes are possible genetic determinants for the risk of ischemic stroke, particularly in patients with multiple small-artery occlusions. However, VEGF polymorphisms had only a weak association with plasma homocysteine levels in the Korean population.