J Korean Soc Hypertens.  2011 Jun;17(2):57-64. 10.5646/jksh.2011.17.2.57.

Expression of Lectin like Oxidized Low Density Lipoprotein Receptor-1 in the Spontaneous Hypertensive Rat with High Cholesterol Diet

• Kim KS
• Park NK
• Kim SY
• Kim DW
• Joo SJ
• Cho MC

• KMID: 2196456
• DOI: http://doi.org/10.5646/jksh.2011.17.2.57

Abstract

BACKGROUND
Lectin-like, oxidized, low-density lipoprotein receptorreceptors (LOX-1) recognizes recognize vascular oxidized low-density lipoprotein (LDL), which may play an important role in the pathogenesis of atherosclerosis. We investigated the expressions expression of LOX-1 and redox-regulating thyoredoxinthioredoxin systems in a hypertension and hypercholesterolemia rat model.
METHODS
Spontaneously hypertensive rats (SHR) and Wistar-Kyoto rat (WKY) rats were fed with a normal cholesterol diet (NC) and a high cholesterol diet (HC) for 4 weeks. Plasma LDL cholesterol levels and blood pressure were measured at 1 and 4 weeks. Histological changes of atherosclerosis in the vessel was evaluated by hematoxylin and eosin staining and immunocytochemistry. The expressions expression of LOX-1 and thyoredoixnthioredoxin were measured by Western western blot analysis.
RESULTS
In the SHR groupsgroup, blood pressure after 4 weeks was significantly higher than initial levels. LDL-cholesterol levels in the SHR-HC group were increased at 4 weeks (15.3 +/- 2.6 mg/dL vs. 20.2 +/- 2.6 mg/dL, p < 0.01) compared with the SHR-NC group. In oxyblot analysis, the degree of oxidative stress of in the SHR-HC group was significantly higher than in the SHR-NC group (p < 0.05). The expressions expression of LOX-1 and Trx were was significantly increased in the SHR-HC group compared with the SHR-NC group (p < 0.05) on western blot analysis. Focal overexpressions overexpression of LOX-1 were was observed at the intima layer of the thoracic aorta, and was which wereonly observed in the SHR-HC group.
CONCLUSIONS
The expressions expression of LOX-1 and oxidative stress were was significantly increased in the "hypertension with hypercholesterol" rat model. These findings suggested suggest that LOX-1 and redox systems may play a certain role in development and progression of atherosclerosis.

Keyword

Atherosclerosis; Hypertension; Oxidative stress

MeSH Terms

Animals
Aorta, Thoracic
Atherosclerosis
Blood Pressure
Blotting, Western
Cholesterol
Cholesterol, LDL
Diet
Eosine Yellowish-(YS)
Glycosaminoglycans
Hematoxylin
Hypercholesterolemia
Hypertension
Immunohistochemistry
Lipoproteins
Lipoproteins, LDL
Oxidation-Reduction
Oxidative Stress
Plasma
Rats
Rats, Inbred SHR
Cholesterol
Cholesterol, LDL
Eosine Yellowish-(YS)
Glycosaminoglycans
Hematoxylin
Lipoproteins
Lipoproteins, LDL

Figure

• 

  Fig. 1. Change of blood pressure and left ventricular wall thickness. (A) SBP change at 4 weeks experiment; WKY-NC, WKY-HC vs. SHR-NC, SHR-HC, p<0.05. (B) Left ventricular wall thickness at 4 weeks experiment; WKY-NC, WKY-HC vs. SHR-NC, SHR-HC, p<0.05. SBP, systolic blood pressure; WKY, Wistar Kyoto rat; SHR, spontaneous hypertensive rat; NC, normal cholesterol diet; HC, high cholesterol diet; LDL, low density lipoprotein. n=5 in each group. *p<0.05.

• 

  Fig. 2. Change of plasma low density lipoprotein levels. Plasma LDL level; WKY-NC vs. WKY-HC, SHR-NC, p<0.05, WKY-NC, WKY-HC, SHR-NC vs. SHR-HC, p<0.01, WKY: Wistar Kyoto rat, SHR: spontaneous hypertensive rat, NC: normal cholesterol diet, HC: high cholesterol diet, LDL: low density lipoprotein. n=5 in each group. *p<0.05, †p<0.01.

• 

  Fig. 3. Expression patterns of oxidative stress in thoracic aorta. (A) Oxyblot analysis of thoracic aorta, WKY-NC vs. WKY-HC, SHR-NC, p<0.05, WKY-NC, WKY-HC, SHR-NC vs. SHR-HC, p<0.01. (B) Representative figure of oxyblot analysis. (C) Expression patterns of TRX in thoracic aorta on western blot analysis, WKY-NC vs. WKY-HC, SHR-NC, p<0.05, WKY-NC, WKY-HC, SHR-NC vs. SHR-HC, p<0.01. (D) Representative figure of western blot analysis of TRX. WKY, Wistar Kyoto rat; SHR, spontaneous hypertensive rat; NC, normal cholesterol diet; HC, high cholesterol diet; TRX, thioredoxin. n=3 in each group. *p<0.05, †p<0.01.

• 

  Fig. 4. Expression patterns of lectin-like oxidized low-density lipoprotein receptor (LOX-1) in thoracic aorta. (A) Expression patterns of LOX-1 in thoracic aorta on western blot analysis, WKY-NC vs. WKY-HC, SHR-NC, p<0.05, WKY-NC, WKY-HC, SHR-NC vs. SHR-HC, p<0.01. (B) Representative figure of western blot analysis of LOX-1. WKY, Wistar Kyoto rat; SHR, Spontaneous hypertensive rat; NC, normal cholesterol diet; HC, high cholesterol diet. n=3 in each group. *p<0.05, †p<0.01.

• 

  Fig. 5. Histological findings of thoracic aorta. (A-D) H&E stain findings of thoracic aorta. (E) Immunohistochemistry finding in SHR-HC group, white arrow tips indicated lectin-like oxidized low-density lipoprotein receptor expressions. WKY, Wistar Kyoto rat; SHR, spontaneous hypertensive rat; NC, normal cholesterol diet; HC, high cholesterol diet.

Reference

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