Effects of miR-155 on hypertensive rats via regulating vascular mesangial hyperplasia

Pathogenesis of miR-155 on nonmodifiable and modifiable risk factors in Alzheimer's disease

Alzheimer's disease (AD) is a common age-related neurodegenerative disease in the central nervous system and is the primary cause of dementia. It is clinically characterized by the memory impairment, aphasia, apraxia, agnosia, visuospatial and executive dysfunction, behavioral changes, and so on. Incidence of this disease was bound up with age, genetic factors, cardiovascular and cerebrovascular dysfunction, and other basic diseases, but the exact etiology has not been clarified. MicroRNAs (miRNAs) are small endogenous non-coding RNAs that were involved in the regulation of post-transcriptional gene expression. miRNAs have been extensively studied as noninvasive potential biomarkers for disease due to their relative stability in bodily fluids. In addition, they play a significant role in the physiological and pathological processes of various neurological disorders, including stroke, AD, and Parkinson's disease. MiR-155, as an important pro-inflammatory mediator of neuroinflammation, was reported to participate in the progression of β-amyloid peptide and tau via regulating immunity and inflammation. In this review, we put emphasis on the effects of miR-155 on AD and explore the underlying biological mechanisms which could provide a novel approach for diagnosis and treatment of AD.

MicroRNA 21 and microRNA 155 levels in resistant hypertension, and their relationships with aldosterone

Aim

MicroRNAs (miRNAs) are non-coding RNA molecules that serve as regulators following gene expression transcription. While studies have investigated the role of miRNAs in the pathogenesis of essential hypertension (HT), very few have considered their place in the pathogenesis of resistant hypertension (RH). The purpose of this study was to investigate levels of miRNA 21 and miRNA 155 in RH and their relationships with aldosterone.

Method

Thirty-two normotensive patients, 30 newly diagnosed HT patients, and 20 RH patients were included in the study. Patients’ demographic data were recorded, and office blood pressure measurement and 24-h ambulatory blood pressure monitoring (24-h ABPM) were performed. Blood specimens were collected for miRNA 21, miRNA 155 and aldosterone measurement. MiRNA 21 and miRNA 155 levels in the control and patient groups and their relations with other demographic and biochemical parameters were then subjected to analysis.

Results

No difference was determined in miRNA 155 levels between the groups, but miRNA 21 and aldosterone levels were significantly higher in the RH group (p < 0.001 and <0.05, respectively). At correlation analysis, miRNA 21 exhibited positive correlation with aldosterone, age, office SBP, 24-h ABPM all-day SBP. A 9.6 copy/uL level for miRNA 21 predicted presence or absence of RH with 95% sensitivity and 71% specificity (AUC:0.823, 95% CI (0.72–0.92).

Conclusion

The study results revealed significantly higher miRNA 21 and aldosterone in RH patients than in healthy individuals and newly diagnosed hypertensives.

Biomechanical signal communication in vascular smooth muscle cells

Biomechanical stresses are closely associated with cardiovascular development and diseases. In vivo, vascular smooth muscle cells are constantly stimulated by biomechanical factors caused by increased blood pressure leading to the non-specific activation of cell transmembrane proteins. Thus, various intracellular signal molecules are simultaneously activated via signaling cascades, which are closely related to alterations in the differentiation, phenotype, inflammation, migration, pyroptosis, calcification, proliferation, and apoptosis of vascular smooth muscle cells. Meanwhile, mechanical stress-induced miRNAs and epigenetics modification on vascular smooth muscle cells play critical roles as well. Eventually, the overall pathophysiology of the cells is altered, resulting in the development of many major clinical diseases, including hypertension, atherosclerosis, grafted venous atherosclerosis, and aneurysm, among others. In this paper, important advances in mechanical signal communication in vascular smooth muscle cells are reviewed.