• International Journal of Industrial Entomology and Biomaterials
• /
• v.14 no.2
• /
• pp.121-126
• /
• 2007

Obesity is a major risk factor for cardiovascular disease. In our case study using animal models for disease states such as obesity or hypertension, we found that, Isaria sinclairii remarkably reduced body weight and ameliorated metabolic abnormalities in Zucker and SHR rats. Genetically obese (fa/fa) Zucker rats were one animal model chosen for this study. Four groups of rats received a standard diet and were treated orally with the following test samples daily for 8 weeks: saline (negative control), ethanol extracts of I. sinclairii, hot water extract of I. sinclairii, or $Xenical^{(R)}$ (30 mg/kg, positive control). Mild reductions (6.3%) in body weight gain were observed in the groups treated with the hot water extract of I. sinclairii compared to the control after 8 weeks. Interestingly, organ weight was greatly reduced by this Dongchunghacho (I. sinclairii), in parallel with the mild reductions in body weight gain and reductions in abdominal fat (adipose tissue). Also observed was a 4.1 % decrease in the ratio of heart weight/body weight compared to the control group. As a hypertensive animal model, SHR (spontaneously hypertensive rat) and WKY (Wistar Kyoto) rats were also administered these extracts for one month. Treatment with the hot water extract of I. sinclairii caused greater reductions in body weight gain for the SHR group (10.9%) compared to the WKY group's (5.2%). Based on these results, I. sinclairii extracts contain selective action for anti-obesity activity, naturally occurring candidate for regulation of body weight increase, as demonstrated in the present study.

• Journal of Life Science
• /
• v.15 no.5 s.72
• /
• pp.703-706
• /
• 2005

The purpose of this study is to investigate the combined effect of L-arginine supplementation and regular physical exercise on HR, BP, eNOS and Macrophage activation using SHR. To examine the differences among HR, BP, eNOS, and Macrophage activity levels, normotensive Wistar-Kyoto rats were used as a control. Thirty two male rats (six weeks old) were divided into four groups; eight WKY control (WKYC), eight SHR control (SHRC), eight SHR supplemented with L-arginine (SHRA), and eight SHR trained and supplemented with L-arginine (SHRTA). Obtained results were as follows : In the heart and blood pressure, there was significant differences anong the four group (p<.05) compare to SHRC. In the eNOS levels, there was significant differences among the four groups (p<.05) compare to SHRC. In the macrophage activity, there was significant differences among the four groups (p<.05) compare to SHRC. In conclusion, For the SHRC group, the level of eNOS is higher than that of WKYC, and we can expect tissue damage caused by toxic free radical. However, this can be stabilized by the L-arginine supplementation and regular physical training. we can also conclude regular aerobic training decrease cardiovascular stress caused by stabled macrophage activity. Therefore, we can trace it is the effect of training in SHR.

• Nutrition Research and Practice
• /
• v.17 no.2
• /
• pp.192-205
• /
• 2023

BACKGROUND/OBJECTIVES: It is known that the renin-angiotensin system (RAS) in the brain could regulate cognitive functions as well as blood pressure. Inhibition of RAS for the improvement of cognitive function may be a new strategy, but studies so far have mostly reported on the effects of RAS inhibition by drugs, and there is no research on cognitive improvement through RAS inhibition of food ingredients. Therefore, this study investigated the effect of curcumin on blood pressure and cognitive function and its related mechanism in spontaneously hypertensive rat/Izm (SHR/Izm). MATERIALS/METHODS: Six-week-old SHR/Izm rats were divided into 5 groups: control group (CON), scopolamine group (SCO, drug for inducing cognitive deficits), positive control (SCO and tacrine [TAC]), curcumin 100 group (CUR100, SCO + Cur 100 mg/kg), and curcumin 200 group (CUR200, SCO + Cur 200 mg/kg). Changes in blood pressure, RAS, cholinergic system, and cognitive function were compared before and after cognitive impairment. RESULTS: The SCO group showed increased blood pressure and significantly reduced cognitive function based on the y-maze and passive avoidance test. Curcumin treatments significantly improved blood pressure and cognitive function compared with the SCO group. In both the CUR100 and CUR200 groups, the mRNA expressions of angiotensin-converting enzyme (ACE) and angiotensin II receptor type1 (AT1), as well as the concentrations of angiotensin II (Ang II) in brain tissue were significantly decreased. The mRNA expression of the muscarinic acetylcholine receptors (mAChRs) and acetylcholine (ACh) content was significantly increased, compared with the SCO group. CONCLUSIONS: The administration of curcumin improved blood pressure and cognitive function in SCO-induced hypertensive mice, indicating that the cholinergic system was improved by suppressing RAS and AT1 receptor expression and increasing the mAChR expression.

• Biomolecules & Therapeutics
• /
• v.4 no.2
• /
• pp.205-207
• /
• 1996

Clonidine, an antihypertensive drug, stimulates postsynaptic alpha-2 adrenergic receptors in the central nervous system and lowers arterial pressure through the effects on both cardiac output and peripheral resistance. However, many patients experience that sedation and xerostomia occur upon oral administration of clonidine. These side effects are due to high plasma peak concentration and can be avoided when clonidine is given transdermally. In this study, we tested the antihypertensive effects of trandermal administration of clonidine patch on spontaneously hypertensive rat (SHR) which is a model animal for human essential hypertension. Forty eight SHR (male) were divided into six groups according to the dose levels, respectively. After transdermal administration of clonidine patch of each dose, systolic blood pressure and heart rate were measured. Clonidine patch produced maximal antihypertensive and bradycardiac effects 48 hrs after administration and antihypertensive effects showed dose-dependency. We suggest that antihypertensive effects of clonidine patch are similar to those of orally given clonidine and clonidine patch can be used instead of clonidine tablet.

• The Korean Journal of Physiology
• /
• v.23 no.2
• /
• pp.253-261
• /
• 1989

Responses of atrial natriuretic peptide (ANP), aldosterone and renin release to acute volume expansion were compared in normotensive Wistar and spontaneously hypertensive rat (SHR) fed low or high-sodium diet (2 or 25 mmol Na/100 g diet). Experimental diets were fed for 6 weeks from 7-week-old and the growth rate was similar in all groups. In the morning of the experiment, catheters were inserted under ether anesthesia in femoral artery for pressure recording and blood collection, femoral vein for saline infusion, and bladder for urine collection. Then, the rats were placed in restraining cages. When the rats were recovered from anesthesia and the arterial pressure became stabilized, control urine and blood samples were collected. Then, 0.9% saline was infused for 30 min for volume expansion (3% BW). Arterial pressure was significantly higher in the high-sodium SHR but there was no difference between the two groups of Wistar rats. Control plasma levels of Na, K, ANP, renin activity, and hematocrit were not different among the 4 groups. However, plasma aldosterone level was significantly higher in the low-sodium groups. Wistar low-sodium rats showed approximately two times higher plasma aldosterone level than the SHR counterpart. Volume expansion produced a marked increase in plasma ANP level, especially in the high-sodium groups. The low-sodium groups of both strains showed approximately two-fold increase in plasma ANP level. Following a volume expansion plasma aldosterone level and renin activity decreased in all groups. There was a significant logarithmic positive correlation between plasma renin activity and aldosterone concentration. The low-sodium rats produced a greater increase in aldosterone release by small increase in plasma renin than did the high-sodium rats. The low- and high-sodium rats produced a similar degree of diuresis and natriuresis after volume expansion. However, SHR produced a greater natriuresis than did the Wistar rats. The above results indicate that regulatory mechanisms of ANP, aldosterone and renin release are different between the normotensive and hypertensive rats, and between the low- and high-sodium groups.

• Journal of the Korean Society of Food Culture
• /
• v.24 no.3
• /
• pp.338-343
• /
• 2009

This study was conducted to investigate the effects of Takju lees hot water extracts on the blood pressure in spontaneously hypertension rats (SHR). Twenty eight male SHR were grouped by their blood pressure and fed a control diet or experimental diets containing 1% (G1), 2% (G2), or 4% (G4) Takju lees extracts for 4 weeks. Food intake was not significantly different among the groups. However, body weight gain was significantly lower in groups fed the Takju lees extract than the control group. The systolic blood pressure was significantly lower in the Takju lees extract containing groups (especially in G4 group) than the control groups. In addition, mean blood pressure {(systolic+dyastolic)/2} decreased with an increase in the amount of Takju lees extract in the diet and feeding period. Takju lees extract decreased angiotensin I converting enzyme (ACE) activity in a dose-dependent manner. These results suggest that the Takju lees extract exert an antihypertensive effect by decreasing ACE activity.

• Biomolecules & Therapeutics
• /
• v.5 no.3
• /
• pp.299-305
• /
• 1997

In order to investigate the pharmacological properties of ι-muscone, effects of ι-muscone and musk were studied on the cardiovascular system with various experimental models. In isolated rat aorta, ι-muscone and musk made the relaxation of blood vessels in maximum contractile response to phenylephrine (10$^{-6}$ M) in endothelium-containing rings of the rat aorta, but not in endothelium-denuded rings. However, ι-muscone and musk in the presence of the inhibitor of NO synthase and guanylate cyclase did not make the relaxation of blood vessels. In spontaneously hypertensive rats (SHRs), ι-muscone and musk slightly reduced blood pressure but significantly decreased heart rate. In the isolated perfused rat hearts, ι-muscone and musk did not affect significantly on LVDP, contractile force, coronary flow and (-dp/dt)/(+dp/dt). These results suggest that ι-muscone and musk have weak cardiovascular effects with relaxation of blood vessel and decrease of heart rate, but without significant cardiac functions.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.6
• /
• pp.899-905
• /
• 2003

The effects of cooked soybean and a traditional fermented soy product, chongkukjang, on blood pressure and lipid metabolism were studied in spontaneously hypertensive rat (SHR). SHRs were divided into 3 groups (n=10, male), and fed casein, powders of cooked soybean, and chongkukjang as dietary protein sources for 6 weeks. Body weight gain was not different among experimental groups, but food efficiency was increased in groups fed cooked soybean and chongkukjang diets compared to control group. Consumption of cooked soybean and chongkukjang for 6 weeks in SHR significantly suppressed blood pressure rise with aging (p<0.05). Feeding of cooked soybean and chongkukjang to SHR decreased plasma triacylglycerols (p<0.05) by 21.6% and 30.2% and LDL-cholesterol by 30.0% and 27.5%, respectively. Addition of cooked soybean and chongkukjang to the diet resulted in reduction of total lipids and triacylglycerols of liver, while consumption of cooked soybean and chongkukjang resulted in the increase of fecal cholesterol and bile acid excretions, respectively (p<0.05). Cooked soybean and chongkukjang diets down-regulated the activity of hepatic HMG-CoA reductase by 56.4% and 94.5%, compared to control, respectively. From the above-mentioned results, it can be concluded that consumption of cooked soybean and chongkukjang might be helpful in preventing cardiovascular disease by suppressing blood pressure rise and hyperlipidemia.

• Korean Journal of Food Science and Technology
• /
• v.34 no.4
• /
• pp.737-740
• /
• 2002

To determine the relations between antihypertensive effect and ${\gamma}-aminobutyric$ acid, mycelial weight and pigment of Monascus, ethanol koji extracts were prepared from Monascus koji and each of three grade was classified based on ${\gamma}-aminobutyric$ acid content, glucosamine content and hue angle value, respectively. Each extract was orally administrated on male spontaneously hypertensive rats and its antihypertensive effect was compared. Most of koji extracts showed antihypertensive activity regardless of their ${\gamma}-aminobutyric$ acid content, glucosamine content or hue angle value. Therefore, hypotensive activity of koji extract was not dependent on above three components.

• Korean Journal of Food Science and Technology
• /
• v.30 no.6
• /
• pp.1476-1479
• /
• 1998

Effect of chitosan oligosaccharides on the ACE (angiotensin I converting enzyme) inhibition and antihypertension in SHR (Spontaneously hypertensive rat) was examined. The ACE inhibition activity was observed in all the chitosan oligosaccharides used in this study, and chitosan trimer exhibited the highest inhibitory activity $(IC_{50}=0.9{\mu}M)$ compared with other chitosan oligosaccharides $(IC_{50}\;:\;2.4{\sim}100\;{\mu}M)$. The results suggested that chitosan trimer was a good inhibitor of ACE in molecular level. When the single oral dose (2.14 mg/kg, similar to dose level of Captopril, known as strong ACE inhibitor) of chitosan trimer was given to 8 or 21 week aged SHR, the blood pressure reduction of both SHRs in 4hrs were $27{\pm}4.8\;mmHg\;and\;36{\pm}4.3\;mmHg$, respectively. Therefore, it was suggested that chitosan trimer could be applicable as natural ACE inhibitor related to antihypertension.