The Link Between Human Cytomegalovirus (HCMV) and Hypertension

It has been reported that mouse cytomegalovirus infection alone can elevate the blood pressure in mice. Since HCMV has uniquely evolved with its human host, with little genetic similarity to the animal CMV counterparts, and it only replicates in human, an epidemiological study is required to define the relevance of HCMV infection and expression of hcmv-miRNA-UL112 to the pathogenesis of essential hypertension.

The investigators found that hcmv-miR-UL112, a human cytomegalovirus (HCMV)-encoded miRNA, was highly expressed in the hypertensive patients. Among the top miRNA target predictions, the investigators demonstrate that IRF-1 is a direct target gene of hcmv-miR-UL112, along with MICB that has been previously reported. Both IRF-1 and MICB play critical roles in immuno/inflammatory and anti-infection response. Thus, the investigators speculated that IRF-1 and MICB repression by hcmv-miR-UL112 could be considered a unifying mechanism that evades the host response at several levels: antiviral, inflammatory, and immune. In addition, there is an increasing evidence that IRF-1 may be important in apoptosis, angiogenesis, neointima formation and the pathogenesis of vascular diseases. IRF-1 can up-regulate angiotensin II type 2 receptor (AGTR2) that exerts antiproliferative and proapoptotic actions and affects regulation of blood pressure. It has been reported that the targeted disruption of the mouse AGTR2 gene resulted in a significant increase in blood pressure and increased sensitivity to angiotensin II. The nitric oxide synthase expression and NO synthesis in macrophages and distinct cardiomyocytes are induced and controlled by IRF-1 in response to inflammation, important steps in vascular biology that may improve endothelial function and inhibit smooth muscle cell migration, and a key pathophysiological event in hypertension. Collectively, these reports support a strong relationship between IRF-1 regulation and hypertension, indicating a potential role of hcmv-miR-UL112 and HCMV infection in the pathogenesis of hypertension.Thus, the investigators want to investigate the potential link between HCMV infection and essential hypertension.