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ORIGINAL ARTICLE
Year : 2013  |  Volume : 26  |  Issue : 1  |  Page : 35-43

Garlic improves altered vascular reactivity and plasma lipids in high cholesterol-fed rats


Department of Clinical Physiology, Faulty of Medicine, Menoufia University, Sers El Lyan, Menoufia, Egypt

Date of Submission17-Mar-2013
Date of Acceptance25-Mar-2013
Date of Web Publication26-Jun-2014

Correspondence Address:
Yahya M Naguib
Clinical Physiology Department, Menoufia University, Menoufia
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.7123/01.MMJ.0000429487.84025.f2

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  Abstract 

Objective

The aim of this work was to study the effect of garlic on the lipid profile of hypercholesterolemic rats and investigate the vascular reactivity to norepinephrine and acetylcholine in hypercholesterolemic rats treated with garlic in-vitro experiments.

Background

Hypercholesterolemia is considered an important risk factor for the development of atherosclerosis; currently, there is a major trend to use herbal remedies for the treatment and prevention of hypercholesterolemia and garlic is used for this purpose.

Methods

Forty male rats were divided into the following four groups of 10 animals each: (i) normal diet-fed animals (control), (ii) hypercholesterolemic animals, (iii) hypercholesterolemic garlic-treated animals, and (iv) hypercholesterolemic garlic-prophylactic animals. The animals were fed a standard food preparation enriched with 2% cholesterol for 2 months and soya bean oil. Thirty days after beginning the experiment, garlic was administered in the hypercholesterolemic garlic-treated group whereas in the hypercholesterolemic garlic-prophylactic group garlic was administered from the start till the end of the experiment. At the end of the experiment, a blood sample was drawn from each rat to determine total cholesterol and to separate the lipoproteins; also, a segment of the thoracic aorta was removed to study endothelial function (vascular reactivity).

Results

Garlic reduced the total serum cholesterol levels and low-density lipoprotein-cholesterol levels significantly. Endothelium-dependent relaxation was significantly greater in the treated and prophylactic group compared with that in the hypercholesterolemic group.

Conclusion

Garlic played a significant role in prophylaxis and treatment of hypercholesterolemia and improvement of endothelial dysfunction.

Keywords: endothelial dysfunction, garlic, hypercholesterolemia


How to cite this article:
Rahman E, Donia SS, Naguib YM. Garlic improves altered vascular reactivity and plasma lipids in high cholesterol-fed rats. Menoufia Med J 2013;26:35-43

How to cite this URL:
Rahman E, Donia SS, Naguib YM. Garlic improves altered vascular reactivity and plasma lipids in high cholesterol-fed rats. Menoufia Med J [serial online] 2013 [cited 2020 Feb 17];26:35-43. Available from: http://www.mmj.eg.net/text.asp?2013/26/1/35/135424


  Introduction Top


Hyperlipidemia refers to elevated levels of lipids and cholesterol in the blood, and is also identified as dyslipidemia, to describe the manifestations of different disorders of lipoprotein metabolism. Although elevated low-density lipoprotein cholesterol (LDL-C) is considered to be the best indicator of the risk of atherosclerosis 1, dyslipidemia can also indicate elevated total cholesterol (TC) or triglycerides (TG) or low levels of high-density lipoprotein cholesterol (HDL-C).

Familial hypercholesterolemia is an inherited disorder characterized by a high concentration of serum LDL-C. The high LDL-C level frequently gives rise to xanthomas – deposits of cholesterol in peripheral tissues – and accelerated atherosclerosis resulting from cholesterol deposition in the arterial wall, thereby increasing the risk of premature coronary heart disease 2.

Efendy et al. 3 and Ide et al. 4 have observed that aged garlic extract, an aqueous extract from garlic powder, and its constituents lower serum cholesterol level and inhibit the oxidative modification of LDL, and are thus presumed to exert a protective effect against atherosclerosis.

The present work aimed to investigate the effect of garlic on the lipid profile of hypercholesterolemic rats and vascular reactivity to norepinephrine (NE) and acetylcholine (ACh) in hypercholesterolemic rats treated with garlic in-vitro experiments.


  Methods Top


Forty male albino rats of the local strain were used in this study and were divided into four equal groups of 10 rats each group as follows:

Group 1: Rats were fed a normal balanced diet for 2 months and used as the control group.

Group 2: Rats were fed a cholesterolemic enriched diet for 2 months (2% cholesterol).

Group 3: Rats were fed a cholesterolemic enriched diet for 2 months (2% cholesterol) and treated with garlic (2.5 mg/kg/day) for 1 month from the second month.

Group 4 (prophylactic group): Rats were fed a cholesterolemic enriched diet for 2 months (2% cholesterol) and received garlic (2.5 mg/kg/day) daily from the beginning of the experiment coinciding with feeding the rats a hypercholesterolemic diet.

The cholesterolemic enriched diet consisted of normal (usual) rat diet and cholesterol 2% and soya bean oil. At the end of the study, rats were sacrificed by cervical decapitation, and aortic rings were then taken to determine the effect of NE on their contractile activity and the effect of ACh on the relaxation of aortic ring precontracted by NE.

At the end of the experiment, another blood sample was obtained to determine serum cholesterol levels and to separate the lipoproteins. Blood samples were collected from the retro-orbital venous plexus of the rat using a fine nonheparinized capillary tube introduced into the medial epicanthus of the rat’s eye. Two milliliters of blood was collected in a clean, graduated centrifuge tube and left to clot at 25°C in a water bath for 15 min. The supernatant serum was collected in two dry tubes 5.

The total serum cholesterol level was measured using commercial enzymatic kits in a spectrophotometer (Genesys 10; Spectronics, Spectronic GENESYS 10, Thermo Electron Scientific Instruments Corporation, Madison, Wisconsin, USA) 6 and the results were expressed in mg/dl.

At the end of the experiments, rats were sacrificed by cervical decapitation and the thorax of each rat was opened and the thoracic aorta was cut through as near the heart as possible and dissected free as far as the diaphragm. The aorta was then transferred to a Petri dish containing Krebs’s solution at room temperature aerated with carbogen (95% oxygen and 5% carbon dioxide). The aorta was cleaned from adherents and then cut into 2.5–3 mm rings. Aortic rings were then suspended in a 10 ml organ bath, containing the freshly prepared Krebs’s solution maintained at 37°C, and bubbled continuously with carbogen gas.

The preparations were attached to a force transducer and isometric tension was recorded on a polygraph. Aortic rings were allowed to equilibrate for 60 min. A resting tension of 1 g was maintained throughout the experiment. The rat aortic ring preparation was used to estimate the changes in vascular reactivity in response to NE (10−7 and 10−5), and relaxation of aortic rings [preconstricted by NE (10−5)] in response to ACh (10−4) 7.

The bath was washed out three times with fresh Krebs’ solution before the next substance was added and the rings were allowed to stabilize for 1 h (isolated rat aortic ring technique) 7.

Relaxation in response to 1×10–6 ACh was calculated as a percentage of:(preconstricted tension−recorded tension)×100/preconstricted tension.

The t-test was used to assess the statistical significance of the difference between two means. Using the t-test and the degree of freedom, the P value was calculated from special tables; thus, the significance of the results was determined from the ‘t’ distribution tables.

P<0.05, insignificant difference; P>0.05, significant difference.

P>0.01, highly significant difference; P>0.001, very highly significant difference.


  Results Top


[Figure 1] and [Table 1] show that in the control group, the serum TC was 90.27±1.54 mg/dl and in the hypercholesterolemic group, the serum TC showed a significantly higher level (P1<0.001) of 165.17±4.76 mg/dl compared with the control group. The hypercholesterolemic garlic-prophylactic group showed a significantly lower level (P2<0.001) of 100.03±3 mg/dl compared with the hypercholesterolemic group and the hypercholesterolemic garlic-treated group showed a significantly lower level (P2<0.001) of 113.67±2.32 mg/dl compared with the hypercholesterolemic group.
Table 1: Lipid profile in control, hypercholesterolemic, hypercholesterolemic garlic-treated, and hypercholesterolemic garlic-prophylactic male albino rats

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Figure 1: Rat serum total cholesterol in various groups.

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The hypercholesterolemic garlic-prophylactic group showed an insignificantly higher level (P1>0.05) of 100.03±3 mg/dl compared with the control group and the hypercholesterolemic garlic-treated group showed a significantly higher level (P1<0.001) of 113.67±2.32 mg/dl compared with the control group.

[Figure 2] and [Table 1] show that in the control group, the level of serum TG was 67.30±10.55 mg/dl and in the hypercholesterolemic group, the serum TG showed a significantly higher level (P1<0.001) of up to 141.52±9.81 mg/dl compared with the control group. The hypercholesterolemic garlic-prophylactic group showed an insignificantly lower level (P2>0.05) of 120.16±5.58 mg/dl compared with the hypercholesterolemic group and the hypercholesterolemic garlic-treated group showed an insignificantly higher level (P2>0.05) of 149.04±5.70 mg/dl compared with the hypercholesterolemic group.
Figure 2: Rat serum triglyceride in various groups.

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The hypercholesterolemic garlic-prophylactic group showed a significantly higher level (P1<0.001) of 120.16±5.58 mg/dl compared with the control group and the hypercholesterolemic garlic-treated group showed a significantly higher level (P1<0.001) of 149.04±5.70 mg/dl compared with the control group.

[Figure 3] and [Table 1] show that in the control group, the serum LDL was 28.21±3.27 mg/dl and in the hypercholesterolemic group, the serum LDL showed a significantly higher level (P1<0.001) of 88.23±5.03 mg/dl compared with the control group.
Figure 3: Rat serum low-density lipoprotein (LDL) in various groups.

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The hypercholesterolemic garlic-prophylactic group showed a significantly lower level (P2<0.001) of 24.09±2.58 mg/dl compared with the hypercholesterolemic group and the hypercholesterolemic garlic-treated group showed a significantly lower level (P2<0.001) of 36.58±1.54 mg/dl compared with the hypercholesterolemic group.

The hypercholesterolemic garlic-prophylactic group showed an insignificantly lower level (P1>0.05) of 24.09±2.58 mg/dl compared with the control group and the hypercholesterolemic garlic-treated group showed an insignificantly higher level (P1>0.05) of 36.58±1.54 mg/dl compared with the control group.

[Figure 4] and [Table 1] show that in the control group, the serum HDL was 49.66±1.95 mg/dl and in the hypercholesterolemic group, the serum HDL showed an insignificantly higher level (P1>0.05) of 49.82±1.74 compared with the control group. The hypercholesterolemic garlic-prophylactic group showed an insignificantly higher level (P2>0.05) of 51.87±1.77 mg/dl compared with the hypercholesterolemic group and the hypercholesterolemic garlic-treated group showed an insignificantly lower level (P2>0.05) of 47.30±2.05 mg/dl compared with the hypercholesterolemic group.
Figure 4: Rat serum high-density lipoprotein (HDL) in various groups.

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The hypercholesterolemic garlic-prophylactic group showed an insignificantly higher level (P1>0.05) of 51.87±1.77 mg/dl compared with the control group and the hypercholesterolemic garlic-treated group showed an insignificantly lower level (P1>0.05) of 47.30±2.05 mg/dl compared with the control group.

[Figure 5] and [Table 2] show the percentage of vasodilatation induced by 1×10–6 mol/l ACh in the aortic rings precontracted by 1×10–5 mol/l NE in the control, hypercholesterolemic, hypercholesterolemic garlic-prophylactic, and hypercholesterolemic garlic-treated groups. As shown in the table, the percentage of vasodilatation induced by 1×10–6 mol/l ACh of the hypercholesterolemic group was 72.5±1.25%, which was significantly (P<0.001) lower than the corresponding value in the control group. The same table also shows that the percentage of vasodilatation induced by 1×10–6 mol/l ACh of the hypercholesterolemic garlic-treated group was 80±2.04%, which was significantly (P2<0.05) higher than the corresponding value in the hypercholesterolemic group. In the hypercholesterolemic garlic-prophylactic group, the percentage of vasodilatation induced by 1×10–6 mol/l ACh was significantly higher compared with the hypercholesterolemic group (P2<0.001).
Table 2: Percentage of vasodilatation induced by 1×10–6 mol/l acetylcholine in aortic rings precontracted by 1×10–5 mol/l norepinephrine in control, hypercholesterolemic, hypercholesterolemic garlic-treated, and hypercholesterolemic garlic-prophylactic group

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Figure 5: Percentage of vasodilatation induced by 1×10–6 mol/l acetylcholine (ACh) in aortic rings precontracted by 1×10–5 mol/l norepinephrine in control, hypercholesterolemic, hypercholesterolemic garlic-treated, and hypercholesterolemic garlic-prophylactic groups.

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The same table also shows that the percentage of vasodilatation induced by 1×10–6 mol/l ACh of the hypercholesterolemic garlic-treated group was 80±2.04%, which was significantly (P1<0.001) lower than the corresponding value in the control group. In the hypercholesterolemic garlic-prophylactic group, the percentage of vasodilatation induced by 1×10–6 mol/l ACh was insignificantly lower compared with the control group (P1>0.05).

[Figure 6] and [Table 3] show the vascular reactivity of the aortic ring (mg tension) to 1×10–5 mol/l NE in the control, hypercholesterolemic, hypercholesterolemic garlic-prophylactic, and hypercholesterolemic garlic-treated groups. As shown in the table, the vascular reactivity of the aortic ring (mg tension) to 1×10–5 mol/l NE of the hypercholesterolemic group was 98.25±3.11 mg tension, which was significantly (P1<0.01) higher than the corresponding value in the control group. The same table also shows that the vascular reactivity of aortic ring (mg tension) to 1×10–5 mol/l NE of the hypercholesterolemic garlic-treated group was 80.25±3.11 mg tension, which was significantly (P2<0.01) lower than the corresponding value in the hypercholesterolemic group.
Table 3: Vascular reactivity (mg tension) to 10–5 mol/l norepinephrine in control, hypercholesterolemic, hypercholesterolemic garlic-treated, and hypercholesterolemic garlic-prophylactic groups

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Figure 6: Vascular reactivity (mg tension) to 10–5 mol/l norepinephrine in control, hypercholesterolemic, hypercholesterolemic garlic-treated, and hypercholesterolemic garlic-prophylactic groups.

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In the hypercholesterolemic garlic-prophylactic group, the vascular reactivity of the aortic ring (mg tension) to 1×10–5 mol/l NE was 45.25±2.05 mg tension, which was significantly (P2<0.01) lower than the corresponding value in the hypercholesterolemic group.

The same table also shows that the vascular reactivity of the aortic ring (mg tension) to 1×10–5 mol/l NE of the hypercholesterolemic garlic-treated group was 80.25±3.11 mg tension, which was significantly (P1<0.01) higher than the corresponding value in the control group.

In the hypercholesterolemic garlic-prophylactic group, the vascular reactivity of the aortic ring (mg tension) to 1×10–5 mol/l NE was 45.25±2.05 mg tension, which was insignificantly (P2>0.05) higher than the corresponding value in the control group.


  Discussion Top


The present work aimed to study the effect of garlic on the lipid profile of hypercholesterolemic rats and investigate the vascular reactivity to NE and ACh in hypercholesterolemic rats treated with garlic in-vitro experiments; the data obtained showed that the administration of cholesterol 2% for 8 weeks showed a significantly higher level of TC, TG, and low-density cholesterol LDL compared with the corresponding values in normal diet-fed control rats. These results were in agreement with those obtained by Otunola et al. 8, who reported that feeding rats with a high-fat diet for 8 weeks resulted in a significant increase in the serum TC, LDL, and TG levels, but with no such difference in the HDL level in both groups. These results were in agreement with those of Ohtani et al. 9, who reported that hepatic LDL receptor activity was considerably suppressed with a cholesterol-enriched diet as about two-thirds of LDL is removed by hepatic LDL receptors. Therefore, suppression of hepatic LDL receptors may have led to the elevated level of LDL that occurs with a cholesterol-enriched diet; at the same time, the decrease in the activity of these receptors resulted in oversynthesis of LDL. Also, the changes in the lipoprotein structure produced by a high-cholesterol diet and hypothyroidism may lead to reduced affinity of LDL to LDL receptors 10.

Galle et al. 11 reported that numerous studies have shown that hypercholesterolemia is associated with the development of atherosclerosis. During this process, various alterations in vascular reactivity have been observed, in particular, attenuation of endothelium-dependent vasodilations and increased responsiveness to different contractile agonists.

Also, the aim of the present work is to explore the effect of hypercholesterolemia on the vascular endothelium; for this purpose, aortic rings from hypercholesterolemic groups were dissected free and mounted in an organ path to study the vascular reactivity to ACh and NE.

The present work showed that the response to NE was higher in the hypercholesterolemic group than that of the control group and the response to ACh was lower in the hypercholesterolemic group than that of the control group, and these were in agreement with the results of Rosendorff 12.

The previous effect of garlic may have been induced by the release of nitric oxide (NO); this explanation is in agreement with the results of Wang et al. 13, who showed that the administration of L-arginine, the NO precursor, reduced the impairment of ACh vasodilatation in iliac arteries from hypercholesterolemic rabbits. In addition, they found that arginine reduced the vascular lesions induced by balloon injury. In another study 14 in hypercholesterolemic rabbits, the impaired vasodilator response of the abdominal aorta to ACh was normalized in animals fed L-arginine. Also, histomorphometric measurements showed a marked decrease in intimal thickening in L-arginine-supplemented hypercholesterolemic animals. Finally, in hypercholesterolemic patients, the impairment of serotonin-induced vasodilatation (also endothelium-dependent) of forearm vessels was normalized either by lipid-lowering or by intra-arterial L-arginine 15. NO synthase is downregulated by oxidized LDL-C; this effect was prevented by simvastatin and lovastatin 16. In hypercholesterolemic animals, there is evidence that the changes in smooth muscle cell reactivity are associated with an increased appearance of reactive oxygen species. However, limited information has been reported on the situation in humans and how these pathological events may be or may not be interrelated 17.

The present study showed that administration of garlic 2.5 mg/kg/day led to significantly higher levels of cholesterol and also LDL in comparison with the hypercholesterolemic group, with an insignificant difference in the TG and HDL level; similar results have been reported by other authors 18–20.

The protective effect of garlic on atherosclerosis has been attributed to its capacity to reduce the lipid content in the arterial wall. Garlic exerts direct antiatherogenic (preventive) and antiatherosclerotic (causing regression) effects at the level of the artery wall. Garlic depressed the hepatic activities of lipogenic and cholesterogenic enzymes such as malic enzyme, fatty acid synthase, glucose-6-phosphate dehydrogenase, and 3-hydroxy-3-methyl-glutaryl-CoA reductase. Garlic also increased the excretion of cholesterol, as manifested by enhanced excretion of acidic and neutral steroids after the administration of garlic. LDL isolated from human participants administered aged garlic extract and an aqueous garlic extract was found to be significantly more resistant to oxidation. These data indicate that suppressed LDL oxidation may be one of the powerful mechanisms that account for the benefits of garlic in atherosclerosis. Allicin was identified initially as the active compound responsible for an antiatherosclerotic effect. However, recent in-vitro studies have shown that water-soluble organosulfur compounds, especially S-allyl cysteine, present in aged garlic extracts, and diallyl-di-sulfide, present in garlic oil, are also potent inhibitors of cholesterol synthesis 21.

Interestingly, a study was carried out to evaluate the hypocholesterolemic effect of an enteric-coated garlic supplement standardized for allicin-releasing potential in mild to moderate hypercholesterolemic patients. The results showed that at the end of the 12-week intervention period, the changes in TC, HDL-C, LDL-C, and TG were significantly different between the garlic and the placebo groups. The mean TC concentration decreased in the garlic group by 0.36 mmol/l compared with an increase recorded in the placebo group (0.13 mmol/l). Similarly, LDL-C was also reduced in the garlic group by 0.44 mmol/l, whereas the placebo group showed an increase of 0.18 mmol/l. Surprisingly, HDL-C was significantly increased in the placebo group (0.09 mmol/l) compared with the minimal reduction in the garlic group (0.02 mmol/l). The changes in TG were observed to be 0.16 mmol/l for the garlic group and 20.29 mmol/l for the placebo. No significant differences were observed in the change between groups for the LDL-C/HDL-C ratio 22.

In addition, it was found in the present work that garlic significantly reduced the vascular reactivity to NE in hypercholesterolemic garlic-treated rats compared with the corresponding value in hypercholesterolemic groups, and the response to ACh was enhanced compared with the hypercholesterolemic group, which is in agreement with Ganado et al. 23.

It has been reported by Das et al. 24,25 that garlic activates the NO synthase both in vitro (in cell-free homogenate) and in vivo because the hypertension induced by NG-nitro-L-arginine methyl ester (a NO synthase inhibitor) and the decrease in the urinary levels of NO2/NO3 induced by NG-nitro-L-arginine methyl ester in rats were prevented by treatment with garlic, which strongly suggests that garlic increases NO synthase in vivo. There is a link between garlic and the L-arginine-NO pathway. Amino acid analysis of garlic powder showed that it is a rich source of arginine, the precursor of NO.

In a trial to test the ability of garlic to act as a prophylactic agent, the rats in this group were administered garlic 2.5 mg/kg/day daily from the beginning of the experiment, coinciding with feeding the rats a hypercholesterolemic diet, and it was found that there was a significant reduction in the cholesterol and LDL levels in comparison with the hypercholesterolemic group, whereas there was an insignificant difference in the TG or HDL level.

In addition, in terms of the vascular reactivity, it was found that garlic significantly reduced the vascular reactivity to NE in the group when compared with the corresponding value in the hypercholesterolemic group, and the response to ACh was enhanced compared with the hypercholesterolemic group.


  Conclusion Top


At the end of this work, it can be concluded that hypercholesterolemia exerted a deleterious effect on vascular endothelium. This effect was shown in this work by enhanced vascular reactivity to a sympathomimetic vasoactive agent.

In the present work, from the results of the investigations presented, it can be concluded that the consumption of garlic may exert both protective and curative effects on atherosclerosis.[25]

 
  References Top

1.Jacobson MS.Heart healthy diets for all children: no longer controversial.J Pediatr1998;133:1–2.  Back to cited text no. 1
    
2.Goldstein JLScriver CS.Familial hypercholesterolemia.The metabolic and molecular bases of inherited disease2001:8th ed..New York:McGraw-Hill Book Co.;2863–2913.  Back to cited text no. 2
    
3.Efendy JL, Simmons DL, Campbell GR, Campbell JH.The effect of the aged garlic extract, ‘Kyolic’, on the development of experimental atherosclerosis.Atherosclerosis1997;132:37–42.  Back to cited text no. 3
    
4.Ide N, Nelson AB, BHH Lau.Aged garlic extract and its constituents inhibit CU(2+)-induced oxidative modification of low density lipoprotein.Planta Med1997;63:263–264.  Back to cited text no. 4
    
5.Schermer SSchermer S.Rats haemopiotic system.Blood morphology of laboratory animals1968:1st ed..Philadelphia, PA:Pdl. Davis A Co.;112.  Back to cited text no. 5
    
6.Trinder P.Enzymatic colorimetric method for determination of blood glucose using an oxidase-peroxidase system, a non-carcinogenic chromagen, cholesterol and triglycerides.Am Clin Biochem1969;6:24–30.  Back to cited text no. 6
    
7.Shin IW, Sohn JT, Park KE, Chang KC, Choi JY, Lee HK, et al..A supraclinical dose of tramadol stereoselectively attenuates endothelium-dependent relaxation in isolated rat aorta.Anesth Analg2006;103:366–371.  Back to cited text no. 7
    
8.Otunola GA, Oloyede OB, Oladiji AT, Afolayan AA.Effects of diet induced hypercholesterolemia on the lipid profile and some enzyme activities in female Wistar rats.Afr J Biochem Res2010;4:149–154.  Back to cited text no. 8
    
9.Ohtani H, Hayashi K, Hirata Y, Dojo S, Nakashima K, Nishio E, et al..Effects of dietary cholesterol and fatty acids on plasma cholesterol level and hepatic lipoprotein metabolism.J Lipid Res1990;31:1413–1422.  Back to cited text no. 9
    
10.Gotto AM Jr..Interrelationship of triglycerides with lipoproteins and high-density lipoproteins.Am J Cardiol1990;66:20A–23A.  Back to cited text no. 10
    
11.Galle J, Busse R, Bassenge E.Hypercholesterolemia and atherosclerosis change vascular reactivity in rabbits by different mechanisms.Arterioscler Thromb1991;11:1712–1718.  Back to cited text no. 11
    
12.Rosendorff C.Effects of LDL cholesterol on vascular function.J Hum Hypertens2002;16Suppl 1S26–S28.  Back to cited text no. 12
    
13.Wang BY, Candipan RC, Arjomandi M, Hsiun PTC, Tsao PS, Cooke JP.Arginine restores nitric oxide activity and inhibits monocyte accumulation after vascular injury in hypercholesterolemic rabbits.J Am Coll Cardiol1996;28:1573–1579.  Back to cited text no. 13
    
14.Singer AH, Tsao PS, Wang BY, Bloch DA, Cooke JP.Discordant effects of dietary L-arginine on vascular structure and reactivity in hypercholesterolemic rabbits.J Cardiovasc Pharmacol1995;25:710–716.  Back to cited text no. 14
    
15.Stroes ESG, Koomans HA, De Bruin TWA, Rabelink TJ.Vascular function in the forearm of hypercholesterolaemic patients off and on lipid-lowering medication.Lancet1995;346:467–471.  Back to cited text no. 15
    
16.Laufs U, La Fata V, Plutzky J, Liao JK.Upregulation of endothelial nitric oxide synthase by HMG CoA reductase inhibitors.Circulation1998;97:1129–1135.  Back to cited text no. 16
    
17.Fleischhacker E, Esenabhalu VE, Holzmann S, Skrabal F, Koidl B, Kostner GM, et al..In human hypercholesterolemia increased reactivity of vascular smooth muscle cells is due to altered subcellular Ca2+ distribution.Atherosclerosis2000;149:33–42.  Back to cited text no. 17
    
18.Slowing K, Ganado P, Sanz M, Ruiz E, Tejerina T.Study of garlic extracts and fractions on cholesterol plasma levels and vascular reactivity in cholesterol-fed rats.J Nutr2001;131Suppl994S–999S.  Back to cited text no. 18
    
19.Ebesunun MO, Popoola OO, Agbedana EO, Olisekodiaka JM, Onuegbu JA, Onyeagala AA.The effect of garlic on plasma lipids and lipoproteins in rats fed on high cholesterol enriched diet.Biokemistri2007;19:53–58.  Back to cited text no. 19
    
20.Lu Y, He Z, Shen X, Xu X, Fan J, Wu S, et al..Cholesterol-lowering effect of allicin on hypercholesterolemic ICR mice.Oxid Med Cell Longev2012;2012:489690.  Back to cited text no. 20
    
21.Banerjee SK, Maulik SK.Effect of garlic on cardiovascular disorders: a review.Nutr J2002;1:1–14.  Back to cited text no. 21
    
22.Kannar D, Wattanapenpaiboon N, Savige GS, Wahlqvist ML.Hypocholesterolemic effect of an enteric-coated garlic supplement.J Am Coll Nutr2001;20:225–231.  Back to cited text no. 22
    
23.Ganado P, Sanz M, Padilla E, Tejerina T.An in vitro study of different extracts and fractions of Allium sativum (garlic): vascular reactivity.J Pharmacol Sci2004;94:434–442.  Back to cited text no. 23
    
24.Das I, Khan NS, Sooranna SR.Nitric oxide synthase activation is a unique mechanism of garlic action.Biochem Soc Trans1995;23:136S.  Back to cited text no. 24
    
25.Das I, Khan NS, Sooranna SR.Potent activation of nitric oxide synthase by garlic: a basis for its therapeutic applications.Curr Med Res Opin1995;13:257–263.  Back to cited text no. 25
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

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