Semin Thromb Hemost 2015; 41(04): 423-432
DOI: 10.1055/s-0035-1549848
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Methylation Reactions, the Redox Balance and Atherothrombosis: The Search for a Link with Hydrogen Sulfide

Roberta Lupoli
1   Department of Clinical Medicine and Surgery, “Federico II” University, Naples, Italy
,
Alessandro Di Minno
2   Department of Pharmacy, “Federico II” University, Naples, Italy
,
Gaia Spadarella
1   Department of Clinical Medicine and Surgery, “Federico II” University, Naples, Italy
,
Massimo Franchini
3   Department of Transfusion Medicine and Hematology, Carlo Poma Hospital, Mantova, Italy
,
Raffaella Sorrentino
2   Department of Pharmacy, “Federico II” University, Naples, Italy
,
Giuseppe Cirino
2   Department of Pharmacy, “Federico II” University, Naples, Italy
,
Giovanni Di Minno
1   Department of Clinical Medicine and Surgery, “Federico II” University, Naples, Italy
› Author Affiliations
Further Information

Publication History

Publication Date:
14 May 2015 (online)

Abstract

It is now clear that homocysteine (Hcy) is irreversibly degraded to hydrogen sulfide (H2S), an endogenous gasotransmitter that causes in vivo platelet activation via upregulation of phospholipase A2 and downstream boost of the arachidonate cascade. This mechanism involves a transsulfuration pathway. Based on these new data, clinical and experimental models on the relationships between Hcy and folate pathways in vascular disease and information on the Hcy controversy have been reanalyzed in the present review. Most interventional trials focused on Hcy lowering by folate administration did not exclude patients routinely taking the arachidonate inhibitor aspirin. This may have influenced the results of some of these trials. It is also clear that nutritional intake of folate affects several enzymatic reactions of the methionine–Hcy cycle and associated one-carbon metabolism and, thereby, both methylation reactions and redox balance. Hence, it is conceivable that the abnormally high Hcy levels seen in pathologic states reflect a poorly elucidated perturbation of such reactions and of such balance. While it is unknown whether there is an interplay between H2S, methylation reactions, and redox balance, measuring the sole reduction of blood Hcy that follows folate administration may well be an oversimplified approach to a complex biologic perturbation. The need to investigate this complex framework is thoroughly discussed in this article.

Note

Roberta Lupoli and Alessandro Di Minno equally contributed to the present overview.


 
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