Bone remodeling is a very complex process. Homocysteine (Hcy) is known to modulate this process via several known mechanisms such as increase in osteoclast activity, decrease in osteoblast activity and direct action of Hcy on bone matrix. Evidence from previous studies further support a detrimental effect on bone via decrease in bone blood flow and an increase in matrix metalloproteinases (MMPs...

Objective Elevated plasma homocysteine (Hcy) concentrations have been correlated to a higher incidence of a wide range of disorders such as neural tube defects and cardiovascular disease. Whether plasma Hcy concentration (and changes therein) are an accurate reflection of intracellular concentrations (and changes) in organs like the liver is unknown. Methods Wistar rats were fed Hcy-increasing ...

Homocysteine (Hcy) induces matrix metalloproteinase (MMP)-9 in microvascular endothelial cells (MVECs). We hypothesized that the ERK1/2 signaling pathway is involved in Hcy-mediated MMP-9 expression. In cultured MVECs, Hcy induced activation of ERK, which was blocked by PD-98059 and U0126 (MEK inhibitors). Pretreatment with BAPTA-AM, staurosporine (PKC inhibitor), or Gö6976 (specific inhibitor ...

Low concentrations (0.5-6 nmol/g) of homocysteine (Hcy) have recently been demonstrated in acid extracts of various tissues of the mouse and rat (Ueland, P.M., Helland, S., Broch, O.-J., and Schanche, J.-S. (1984) J. Biol. Chem. 259, 2360-2364). This is referred to as free Hcy in tissues. This paper describes a method for the determination of protein-bound Hcy, which involves precipitation and ...

BACKGROUND There is a growing focus on nutritional therapy for Alzheimer's disease (AD), and controversy exists regarding the association between AD and homocysteine (Hcy), vitamin B12, and folate levels. OBJECTIVE The present study evaluated the association between AD and the combined levels of Hcy, vitamin B12, and folate. METHODS This case-control study consisted of 115 patients with AD ...

AIMS We assessed homocysteine (Hcy) levels in tear fluid and plasma of patients with primary open-angle glaucoma (POAG). We determined the association between Hcy levels, dry eye syndrome and B vitamin status. METHODS This prospective case-control study included 36 patients with POAG and 36 controls. Hcy concentrations were measured by high-performance liquid chromatography. RESULTS Patient...

BACKGROUND Few data are available comparing homocysteine (Hcy) levels in patients with hypertension in different ethnic groups. OBJECTIVES This study sought to determine whether there are associations of blood pressure and Hcy levels in patients with hypertension from Xinjiang Province, China. METHODS We examined the serum total Hcy levels in a total of 451 Chinese of various ethnic groups ...

Homocysteine (HCY) is a pro-inflammatory sulphur-containing redox active endogenous amino acid, which concentration increases in neurodegenerative disorders including amyotrophic lateral sclerosis (ALS). A widely held view suggests that HCY could contribute to neurodegeneration via promotion of oxidative stress. However, the action of HCY on motor nerve terminals has not been investigated so fa...

Homocysteine (Hcy) as an independent risk factor contributes to the occurrence and development of human cardiovascular diseases (CVD). Induction of oxidative stress and apoptosis was commonly accepted as the major mechanism in Hcy-induced cardiotoxicity. Astaxanthin (ATX) as one of the most powerful antioxidants exhibits novel cardioprotective potential against Hcy-induced endothelial dysfuncti...

Elevation of serum homocysteine (Hcy) levels is a risk factor for cardiovascular diseases. Previous studies suggested that Hcy interferes with copper (Cu) metabolism in vascular endothelial cells. The present study was undertaken to test the hypothesis that Hcy-induced disturbance of Cu homeostasis leads to endothelial cell injury. Exposure of human umbilical vein endothelial cells (HUVECs) to ...