1.MicroRNA in the Diseased Pulmonary Vasculature: Implications for the Basic Scientist and Clinician.
Richard C JIN ; Pil Ki MIN ; Stephen Y CHAN
Journal of the Korean Society of Hypertension 2013;19(1):1-16
Since the first descriptions of their active functions more than ten years ago, small non-coding RNA species termed microRNA (miRNA) have emerged as essential regulators in a broad range of adaptive and maladaptive cellular processes. With an exceptionally rapid pace of discovery in this field, the dysregulation of many individual miRNAs has been implicated in the development and progression of various cardiovascular diseases. MiRNA are also expected to play crucial regulatory roles in the progression of pulmonary vascular diseases such as pulmonary hypertension (PH), yet direct insights in this field are only just emerging. This review will provide an overview of pulmonary hypertension and its molecular mechanisms, tailored for both basic scientists studying pulmonary vascular biology and physicians who manage PH in their clinical practice. We will describe the pathobiology of pulmonary hypertension and mechanisms of action of miRNA relevant to this disease. Moreover, we will summarize the potential roles of miRNA as biomarkers and therapeutic targets as well as future strategies for defining the cooperative actions of these powerful effectors in pulmonary vascular disease.
Anoxia
;
Biomarkers
;
Biology
;
Cardiovascular Diseases
;
Hydrogen-Ion Concentration
;
Hypertension, Pulmonary
;
MicroRNAs
;
RNA, Small Untranslated
;
Vascular Diseases
2.Angioplasty on an infarct-related anomalous right coronary artery arising from posterior coronary sinus.
Man-Hong JIM ; Ryan L Y KO ; Carmen W S CHAN ; Stephen C W CHEUNG ; Wing-Hing CHOW
Annals of the Academy of Medicine, Singapore 2010;39(3):258-260
INTRODUCTIONThe objective of this case report was to illustrate the diagnostic and intervention approach of anomalous right coronary artery (RCA).
CLINICAL PICTUREA 60-year-old man presented with acute inferior myocardial infarction. Cardiac catheterisation revealed an anomalous RCA arising from the posterior coronary sinus as the infarct-related artery.
TREATMENTAd hoc percutaneous coronary intervention with stent implantation was performed using a few technical modifications.
OUTCOMEGood angiographic result was achieved within 90 minutes, with 260 mL of contrast used.
CONCLUSIONA high index of suspicion and logical diagnostic and intervention approach are required for the proper management of anomalous RCA.
Angioplasty, Balloon, Coronary ; Cardiac Catheterization ; methods ; Coronary Angiography ; Coronary Vessel Anomalies ; complications ; diagnostic imaging ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; complications ; surgery
4.Hemodynamic and Histopathologic Benefits of Early Treatment with Macitentan in a Rat Model of Pulmonary Arterial Hypertension
Kyung Hee KIM ; Hyung Kwan KIM ; Stephen Y. CHAN ; Yong Jin KIM ; Dae Won SOHN
Korean Circulation Journal 2018;48(9):839-853
BACKGROUND AND OBJECTIVES: Macitentan (MAC) reduces morbidity and mortality among advanced-stage pulmonary arterial hypertension (PAH) patients. However, data regarding the histopathologic and hemodynamic benefits of MAC treatment at an early stage of PAH is lacking. METHODS: One week after monocrotaline (MCT) injection, rats were randomly assigned to MAC (n=16), MAC combined with sildenafil (SIL) (MAC+SIL, n=16), or normal saline (MCT, n=16). Twelve sham rats (Sham) were included for comparison. Right ventricular (RV) systolic function was assessed via echocardiography as the RV fractional area change (RV-FAC). An invasive pressure-volume analysis using a Millar conductance catheter was performed 7 weeks after MCT injection. Rats were subsequently euthanized for histopathologic analysis. RESULTS: RV-right atrial pressure gradient on echocardiography was significantly increased 3 weeks after MCT injection, but was maintained in the Sham. RV-FAC was less deteriorated in the MAC, compared to that in the MCT (44±3% vs. 25±7%, p < 0.05), and the co-administration of SIL showed no additional benefit (45±8%, p > 0.05 vs. the MAC). On invasive hemodynamic analyses, RV end-systolic (196±78 µL) and end-diastolic volumes (310±86 µL), pulmonary artery systolic pressure (89±7.2 mmHg), and end-systolic pressure-volume relationship (−254±25.1) were significantly worse in the MCT vs. in the MAC (101±45 µL, 235±55 µL, 40±10.5 mmHg, and −145±42.1, respectively) and MAC+SIL (109±47 µL, 242±46 µL, 38±9.2 mmHg, and −151±39.2, respectively) (all p < 0.05). However, the MAC and MAC+SIL did not differ (all p > 0.05). On histopathology, both RV and lung fibrosis were significantly reduced in the MAC and MAC+SIL vs. in the MCT (all p < 0.05); the 2 treatment groups did not differ. CONCLUSIONS: MAC treatment at an earlier stage significantly attenuated experimental PAH progression hemodynamically and histopathologically.
Animals
;
Atrial Pressure
;
Blood Pressure
;
Catheters
;
Echocardiography
;
Fibrosis
;
Hemodynamics
;
Humans
;
Hypertension
;
Hypertension, Pulmonary
;
Lung
;
Models, Animal
;
Monocrotaline
;
Mortality
;
Pathology
;
Pulmonary Artery
;
Rats
;
Sildenafil Citrate
5.Hemodynamic and Histopathologic Benefits of Early Treatment with Macitentan in a Rat Model of Pulmonary Arterial Hypertension
Kyung Hee KIM ; Hyung Kwan KIM ; Stephen Y. CHAN ; Yong Jin KIM ; Dae Won SOHN
Korean Circulation Journal 2018;48(9):839-853
BACKGROUND AND OBJECTIVES:
Macitentan (MAC) reduces morbidity and mortality among advanced-stage pulmonary arterial hypertension (PAH) patients. However, data regarding the histopathologic and hemodynamic benefits of MAC treatment at an early stage of PAH is lacking.
METHODS:
One week after monocrotaline (MCT) injection, rats were randomly assigned to MAC (n=16), MAC combined with sildenafil (SIL) (MAC+SIL, n=16), or normal saline (MCT, n=16). Twelve sham rats (Sham) were included for comparison. Right ventricular (RV) systolic function was assessed via echocardiography as the RV fractional area change (RV-FAC). An invasive pressure-volume analysis using a Millar conductance catheter was performed 7 weeks after MCT injection. Rats were subsequently euthanized for histopathologic analysis.
RESULTS:
RV-right atrial pressure gradient on echocardiography was significantly increased 3 weeks after MCT injection, but was maintained in the Sham. RV-FAC was less deteriorated in the MAC, compared to that in the MCT (44±3% vs. 25±7%, p < 0.05), and the co-administration of SIL showed no additional benefit (45±8%, p > 0.05 vs. the MAC). On invasive hemodynamic analyses, RV end-systolic (196±78 µL) and end-diastolic volumes (310±86 µL), pulmonary artery systolic pressure (89±7.2 mmHg), and end-systolic pressure-volume relationship (−254±25.1) were significantly worse in the MCT vs. in the MAC (101±45 µL, 235±55 µL, 40±10.5 mmHg, and −145±42.1, respectively) and MAC+SIL (109±47 µL, 242±46 µL, 38±9.2 mmHg, and −151±39.2, respectively) (all p < 0.05). However, the MAC and MAC+SIL did not differ (all p > 0.05). On histopathology, both RV and lung fibrosis were significantly reduced in the MAC and MAC+SIL vs. in the MCT (all p < 0.05); the 2 treatment groups did not differ.
CONCLUSIONS
MAC treatment at an earlier stage significantly attenuated experimental PAH progression hemodynamically and histopathologically.