Effects of Magnesium Dobesilate on Nitric Oxide Synthase Activity in Endothelial Cells

Increased Intraplatelet ADMA Level May Promote Platelet Activation in Diabetes Mellitus

Background

Antiplatelet therapy has become a standard therapeutic approach in the secondary prevention of cardiovascular system disorders of thrombotic origin. Patients with concomitant diabetes mellitus (DM) obtain fewer benefits from this treatment. Hence, the pathophysiology of altered platelet function in response to glucose metabolism impairment should be of particular interest.

Objectives

The aim of our study was to verify if the platelet expression of the asymmetric dimethylarginine (ADMA) in diabetic patients differs in comparison to the nondiabetic ones. The correlation of platelet-ADMA with platelet activation and aggregation as well as with other risk factors was also investigated. Material and Methods. A total of 61 subjects were enrolled in this study, including thirty-one type 2 diabetic subjects without diabetes-related organ damage. Physical examination was followed by blood collection with an assessment of platelet aggregation, traditional biochemical cardiovascular risk factors, and evaluation of nitric oxide bioavailability parameters in plasma and thrombocytes. Subsequently, the assessment of endothelial function using Peripheral Arterial Tonometry and Laser Doppler Flowmetry (LDF) was performed.

Results

In the DM group, elevated concentration of intraplatelet ADMA and higher ADMA/SDMA ratio compared to the control group was observed. It was accompanied by higher ADP-mediated platelet aggregation and lower microvascular response to a local thermal stimulus measured by LDF in the diabetes group.

Conclusions

Type 2 diabetes is related to higher intraplatelet concentration of asymmetric dimethylarginine (ADMA), which may result in impaired platelet-derived nitric oxide synthesis and subsequent increased platelet activity, as assessed by the ADP-induced aggregation. Laser Doppler Flowmetry, compared to EndoPAT 2000, appears to be a more sensitive indicator of the impaired microvasculature vasodilation in diabetics without the presence of clinically significant target organ damage.

A feasibility study of using biodegradable magnesium alloy in glaucoma drainage device

Technological advances in glaucoma have challenged the traditional treatment paradigm. Historically incisional surgery has been used in cases of advanced disease and/or uncontrolled intraocular pressures resistant to medical or laser interventions. More recently, perhaps due to advancements in imaging, surgery has been suggested to be beneficial earlier in the treatment paradigm. Despite these trends, surgical manipulation of the tissues and unpredictability of wound healing continue to result in surgical failure. Magnesium is an essential element for human body and plays a critically important role in maintaining the functional and structural integrity of several tissues, including the eye. Due to several of its advantageous properties such as non-toxicity, biodegradability, and high biological compatibility, magnesium alloy has attracted great attention as a novel biomaterial. Biodegradable cardiovascular stents made of magnesium alloy have already been introduced into clinical practice. The purpose of this review is to determine if bioabsorbable magnesium alloys can be utilized as a promising candidate for the development of a new generation of glaucoma surgical assistive devices.