**9. Atherosclerosis Regression Clinical Studies of Natural Products**

The AMAR study (Atherosclerosis Monitoring and Atherogenicity Reduction) was designed to estimate the effect of two-year treatment with time-released garlic-based drug Allicor on the progression of carotid atherosclerosis in asymptomatic men in double-blinded placebocontrolled randomized clinical trial. The primary outcome was the rate of atherosclerosis progression, measured by high-resolution B-mode ultrasonography as the increase in caro‐ tid intima-media thickness (IMT) of the far wall of common carotid arteries.

Atherosclerosis affects most vascular beads, and noninvasive imaging of superficial arteries by ultrasound has been recognized as a surrogate measure of overall atherosclerotic burden in numerous studies. Extracoronary atherosclerotic lesions can be quickly and safely evalu‐ ated in the carotids, femoral arteries, and the abdominal aorta. The grade of atherosclerosis in extracoronary sites correlates with a greater number of standard risk factors and, more importantly, with greater cardiac risk [77]. Of the peripheral arterial surrogates, carotid atherosclerosis has been most closely correlated with coronary artery disease [78-82]. Pe‐ ripheral arterial ultrasonography is regarded to be a sensitive tool for the detection of early atherosclerosis and may be useful in assessing response to therapy. Thickening of the inti‐ ma-media of the arterial wall is the earliest detectable anatomic change in the development and progression of atherosclerosis. High-resolution B-mode ultrasonography is widely used for noninvasive quantification of carotid IMT as a measure of subclinical atherosclerosis [83]. Carotid IMT is believed to be a marker of generalized atherosclerosis and is predictive of clinical cardiovascular events [79,81,84-88]. Thus, ultrasound imaging of intima-media thickening in carotid arteries served as a means of monitoring atherosclerosis during Allicor long-term treatment. Indeed, Allicor significantly reduced carotid arterial intima-media thickness compared to baseline and the placebo group. In Allicor recipients, a significant in‐ crease in the IMT in one or both carotid arteries was observed in 30 (32.2%) patients, and was significantly reduced in 44 (47.3%) patients. In 8 patients (8.6%) there were no signifi‐ cant IMT changes in either the carotid artery, and in the remaining 11 patients (11.8%) diver‐ gent changes were observed, i.e. IMT increased in one carotid artery and decreased in the other. IMT lesion progression was observed in 50 (48.5%) placebo cases, and decreased sig‐ nificantly in one or both arteries in 31 (30.1%) patients. Stable situation was observed in 11 (10.7%), and divergent changes occurred in the remaining 7 (6.8%) patients. The difference in the IMT changes between Allicor and placebo recipients was statistically significant (Pear‐

son's chi-square 9.788, P=0.020). Thus, while spontaneous atherosclerosis progression pre‐ vailed in the placebo group, Allicor beneficially impacted early carotid atherosclerosis significantly increasing lesion regressions and reducing the net number of progressive lesions (Figure 3). The trend to IMT reduction in Allicor recipients was observed already af‐ ter first 3 months of the study, and became statistically significant different from the base‐ line measures as well as from placebo group after the first 12 months of treatment. At the end of the two-year study the difference between placebo and Allicor recipients increased and remained statistically significant. The overall lesion progression was clearly different in the treated and untreated groups. IMT in the common carotid artery rose 0.015±0.008 mm annually and above a mean baseline IMT of 0.931±0.009 mm in the placebo group, and fell in Allicor-treated patients at a rate of -0.022±0.007 mm per year (P=0.002). Though the benefit of Allicor was more pronounced in year 1 (-0.028±0.008 mm) it remained significant and as a statistically identical significant difference in year 2 (-0.016±0.007).

in the volume of atherosclerotic plaques in carotid and femoral arteries by 5-18%. The agedependent representation of the plaque volume has shown an increase between 50 and 80 years that was diminished under garlic treatment by 6-13% related to 4 years. So, with garlic application the plaque volume in the whole collective remained practically constant within

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Overall, the regression of subclinical atherosclerosis was much more frequently observed in asymptomatic men who randomly received Allicor than in those who received placebo. A rather high proportion of patients in placebo group who demonstrated spontaneous regres‐ sion, especially at early stages of atherosclerosis, reflects an interesting but poorly under‐ stood aspect of vascular biology that requires further study. The decrease in IMT achieved during the AMAR study is quite comparable with the results of most successful trials with other compounds (Table 4). Although, these studies employed potent lipid-lowering agents either calcium antagonists whose beneficial effects of treatment were attributed to reduc‐ tion in LDL cholesterol, the major risk factor for atherosclerosis development, or arterial

**Trial Medication Mean annual IMT change, mm Reference**

The main scientific goal of the given double-blinded, placebo-controlled randomized study was to test the hypothesis that long-term lowering of serum atherogenicity may prevent the initial stage of atherogenesis, namely, the excessive deposition of cholesterol in the cells of

At the baseline, the sera from 17 patients in placebo group (16.5%) did not induce significant cholesterol accumulation in cultured cells, while the sera from other 86 patients were athero‐ genic, i.e. induced a statistically significant (1.2- to 3.9-fold) increase in intracellular choles‐ terol content (mean result, 166.3±5.5, % of control value). In Allicor-treated patients, 23

the arterial wall, thus inhibiting further formation of atherosclerosis lesion [41,62].

PLAC II Pravastatin 0.068 0.059 [91] KAPS Pravastatin 0.029 0.010 [90] ASAP Simvastatin - -0.009 [92] PREVENT Amlodipine 0.011 -0.015 [93] ASAP Atorvastatin - -0.020 [92] CLAS Cholestipol, niacin 0.010 -0.020 [94, 95] MARS Lovastatin 0.015 -0.028 [94, 96] VHAS Verapamil - -0.028 [97] AMAR Allicor 0.015 -0.022 This study

**Table 4.** The comparative data from clinical trials on carotid atherosclerosis regression

**placebo treatment**

the age-span of 50-80 years [89].

wall stress.

**Figure 3.** The dynamics of IMT changesSolid circles, Allicor-treated patients; open circles, placebo patients. \*, signifi‐ cant IMT change as compared to baseline, P<0.05;#, significant difference from placebo group, P<0.05.

The beneficial effects of Allicor were also revealed in analysis of subgroups of patients who had significant increase or reduction in IMT. IMT progression was almost 2.5 fold higher in the 50 patients in the placebo group with progress (0.070±0.016 mm) than in Allicor-treated patients with atherosclerosis progression (n=30, 0.029±0.011 mm increase, P=0.038). Similar‐ ly, spontaneous atherosclerosis regression in placebo recipients (n=31) was half as promi‐ nent (-0.041±0.014 mm) than in Allicor-treated patients (n=44, -0.082±0.015 mm, P=0.049).

The results obtained in our study are generally in good coincidence with the data from re‐ cent double-blinded placebo-controlled randomized study by Koscielny et al. [89]. It has been demonstrated that 4-year treatment with garlic-based drug Kwai inhibited the increase in the volume of atherosclerotic plaques in carotid and femoral arteries by 5-18%. The agedependent representation of the plaque volume has shown an increase between 50 and 80 years that was diminished under garlic treatment by 6-13% related to 4 years. So, with garlic application the plaque volume in the whole collective remained practically constant within the age-span of 50-80 years [89].

son's chi-square 9.788, P=0.020). Thus, while spontaneous atherosclerosis progression pre‐ vailed in the placebo group, Allicor beneficially impacted early carotid atherosclerosis significantly increasing lesion regressions and reducing the net number of progressive lesions (Figure 3). The trend to IMT reduction in Allicor recipients was observed already af‐ ter first 3 months of the study, and became statistically significant different from the base‐ line measures as well as from placebo group after the first 12 months of treatment. At the end of the two-year study the difference between placebo and Allicor recipients increased and remained statistically significant. The overall lesion progression was clearly different in the treated and untreated groups. IMT in the common carotid artery rose 0.015±0.008 mm annually and above a mean baseline IMT of 0.931±0.009 mm in the placebo group, and fell in Allicor-treated patients at a rate of -0.022±0.007 mm per year (P=0.002). Though the benefit of Allicor was more pronounced in year 1 (-0.028±0.008 mm) it remained significant and as a

**Figure 3.** The dynamics of IMT changesSolid circles, Allicor-treated patients; open circles, placebo patients. \*, signifi‐

The beneficial effects of Allicor were also revealed in analysis of subgroups of patients who had significant increase or reduction in IMT. IMT progression was almost 2.5 fold higher in the 50 patients in the placebo group with progress (0.070±0.016 mm) than in Allicor-treated patients with atherosclerosis progression (n=30, 0.029±0.011 mm increase, P=0.038). Similar‐ ly, spontaneous atherosclerosis regression in placebo recipients (n=31) was half as promi‐ nent (-0.041±0.014 mm) than in Allicor-treated patients (n=44, -0.082±0.015 mm, P=0.049).

The results obtained in our study are generally in good coincidence with the data from re‐ cent double-blinded placebo-controlled randomized study by Koscielny et al. [89]. It has been demonstrated that 4-year treatment with garlic-based drug Kwai inhibited the increase

cant IMT change as compared to baseline, P<0.05;#, significant difference from placebo group, P<0.05.

statistically identical significant difference in year 2 (-0.016±0.007).

200 Current Trends in Atherogenesis

Overall, the regression of subclinical atherosclerosis was much more frequently observed in asymptomatic men who randomly received Allicor than in those who received placebo. A rather high proportion of patients in placebo group who demonstrated spontaneous regres‐ sion, especially at early stages of atherosclerosis, reflects an interesting but poorly under‐ stood aspect of vascular biology that requires further study. The decrease in IMT achieved during the AMAR study is quite comparable with the results of most successful trials with other compounds (Table 4). Although, these studies employed potent lipid-lowering agents either calcium antagonists whose beneficial effects of treatment were attributed to reduc‐ tion in LDL cholesterol, the major risk factor for atherosclerosis development, or arterial wall stress.


**Table 4.** The comparative data from clinical trials on carotid atherosclerosis regression

The main scientific goal of the given double-blinded, placebo-controlled randomized study was to test the hypothesis that long-term lowering of serum atherogenicity may prevent the initial stage of atherogenesis, namely, the excessive deposition of cholesterol in the cells of the arterial wall, thus inhibiting further formation of atherosclerosis lesion [41,62].

At the baseline, the sera from 17 patients in placebo group (16.5%) did not induce significant cholesterol accumulation in cultured cells, while the sera from other 86 patients were athero‐ genic, i.e. induced a statistically significant (1.2- to 3.9-fold) increase in intracellular choles‐ terol content (mean result, 166.3±5.5, % of control value). In Allicor-treated patients, 23 patients (24.7%) had non-atherogenic sera, and in other 70 patients the sera increased intra‐ cellular cholesterol by 1.2- to 3.5-fold (mean result, 172.1±5.8, % of control value).

id accumulation was significantly lowered (P=0.016) approximately by 30% of the initial lev‐ el (95% CI: 16.9, 41.0) already after first 3 months of study, and this effect was maintained during the study. General linear model analysis has demonstrated the statistically signifi‐ cant difference in the dynamic of changes in serum atherogenicity between Allicor-treated

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The presence or absence of serum atherogenicity at the baseline, as well as the extent of se‐ rum-induced intracellular cholesterol accumulation at the baseline, did not correlate with the following changes in IMT. However, the statistically significant correlation has been re‐ vealed between the changes in blood serum atherogenicity during the study and the changes in intima-media thickness of common carotid arteries (r=0.144, P=0.045 for the total study sample). In patients with initially non-atherogenic sera, the correlation between changes in atherogenicity and IMT was stronger (r=0.342, P=0.031). This correlation is ex‐ plained mainly by the arrival of serum atherogenicity during follow-up in a subgroup of placebo recipients with initially non-atherogenic sera; in them the correlation between in‐ crease of atherogenicity and IMT dynamics was the highest (r=0.517, P=0.034).. In patients with initially atherogenic sera, the correlation between changes in atherogenicity and IMT in total group did not reach statistical significance (r=0.147, P=0.067), but in Allicor-treated pa‐ tients in most of whom the decrease in serum atherogenicity was observed, the above pa‐

There is a substantial experimental background to explain the possible mechanisms under‐ lying a direct anti-atherosclerotic action of Allicor. The components of garlic can regulate two main intracellular enzymes responsible for cholesterol intracellular metabolism. Garlic extract stimulates cholesteryl ester hydrolase and inhibits acetyl coenzyme A : cholesterol acyl transferase, thus diminishing intracellular content of cholesteryl esters [98]. Additional‐ ly, garlic extract inhibits cellular proliferative activity and the synthesis of connective tissue matrix components [98,99]. Allicor also possesses antioxidant activity and lowers LDL sus‐ ceptibility to oxidation [99]. Allicor prevents serum-induced cholesterol accumulation in cells cultured in the presence of patient's serum taken after single dose of Allicor adminis‐ tration; in other words, it reduces serum atherogenic potential [99]. In animal studies, garlicbased preparations inhibit the formation of neointimal thickening in cholesterol-fed rabbits [100]. So, it could be easily proposed that long-term Allicor treatment produced a direct anti‐ atherosclerotic effect due to the prevention of lipid deposition and depletion of cholesterol

Garlic contains a variety of organosulfur compounds, amino acids, vitamins and minerals [101]. Some of the sulfur-containing compounds such as allicin, ajoene, S-allylcysteine, Smethylcysteine, diallyl disulfide and sulfoxides may be responsible for antiatherosclerotic activity of garlic [98,100]. Many garlic-based products are present on the market now. As compared to other garlic preparations, dehydrated garlic powder is thought to retain the same ingredients as raw garlic, both water-soluble and organic-soluble, although the pro‐ portions and amounts of various constituents may differ significantly [102,103]. Allicor con‐ tains just garlic powder; on the other hand, it possesses a prolonged mode of action, as its antiatherogenic effect lasts for 12-16 hours after single dose administration [99]. So, Allicor

and placebo groups (P=0.008).

rameters correlated well (r=0.254, P=0.034).

pool already accumulated in arterial wall.

Among patients with non-atherogenic sera at the baseline, in placebo recipients blood serum atherogenicity arrived in 11 cases during the study; in Allicor-treated patients at the end of the study serum atherogenicity was revealed in 9 cases, and in other 14 patients the sera re‐ mained non-atherogenic. The difference between Allicor and placebo recipients was statisti‐ cally significant (Pearson's chi-square 11.023, P<0.001). Thus, Allicor treatment prevented the upraise of blood serum atherogenicity.

Among patients with initially atherogenic sera, in placebo group blood serum atherogenici‐ ty spontaneously decreased in 26 patients, did not change significantly in 28 patients, and in 32 cases there was further increase in blood serum atherogenic potential. On the opposite, in Allicor group serum atherogenicity was decreased in 39 patients by the end of the study, re‐ mained unchanged in 18 patients, and further increase in serum ability to induce intracellu‐ lar cholesterol accumulation was observed only in 13 cases. Again, the difference between Allicor and placebo recipients was statistically significant (Pearson's chi-square 11.274, P=0.004). Thus, Allicor also induced a fall in blood serum atherogenicity, if it existed at the beginning of treatment.

**Figure 4.** The dynamics of serum atherogenicity changesSolid circles, Allicor-treated patients; open circles, placebo pa‐ tients. \*, significant IMT change as compared to baseline, P<0.05;#, significant difference from placebo group, P<0.05.

The overall dynamic of changes in serum atherogenicity is presented in Figure 4. At the baseline, serum taken from patients was able to induce 1.56-fold increase in intracellular cholesterol content in cell culture test. In the placebo group, the mean level of serum athero‐ genic potential did not change significantly during two years of the study. On the opposite, in Allicor-treated patients the mean value for the ability of serum to induce intracellular lip‐ id accumulation was significantly lowered (P=0.016) approximately by 30% of the initial lev‐ el (95% CI: 16.9, 41.0) already after first 3 months of study, and this effect was maintained during the study. General linear model analysis has demonstrated the statistically signifi‐ cant difference in the dynamic of changes in serum atherogenicity between Allicor-treated and placebo groups (P=0.008).

patients (24.7%) had non-atherogenic sera, and in other 70 patients the sera increased intra‐

Among patients with non-atherogenic sera at the baseline, in placebo recipients blood serum atherogenicity arrived in 11 cases during the study; in Allicor-treated patients at the end of the study serum atherogenicity was revealed in 9 cases, and in other 14 patients the sera re‐ mained non-atherogenic. The difference between Allicor and placebo recipients was statisti‐ cally significant (Pearson's chi-square 11.023, P<0.001). Thus, Allicor treatment prevented

Among patients with initially atherogenic sera, in placebo group blood serum atherogenici‐ ty spontaneously decreased in 26 patients, did not change significantly in 28 patients, and in 32 cases there was further increase in blood serum atherogenic potential. On the opposite, in Allicor group serum atherogenicity was decreased in 39 patients by the end of the study, re‐ mained unchanged in 18 patients, and further increase in serum ability to induce intracellu‐ lar cholesterol accumulation was observed only in 13 cases. Again, the difference between Allicor and placebo recipients was statistically significant (Pearson's chi-square 11.274, P=0.004). Thus, Allicor also induced a fall in blood serum atherogenicity, if it existed at the

**Figure 4.** The dynamics of serum atherogenicity changesSolid circles, Allicor-treated patients; open circles, placebo pa‐ tients. \*, significant IMT change as compared to baseline, P<0.05;#, significant difference from placebo group, P<0.05.

The overall dynamic of changes in serum atherogenicity is presented in Figure 4. At the baseline, serum taken from patients was able to induce 1.56-fold increase in intracellular cholesterol content in cell culture test. In the placebo group, the mean level of serum athero‐ genic potential did not change significantly during two years of the study. On the opposite, in Allicor-treated patients the mean value for the ability of serum to induce intracellular lip‐

cellular cholesterol by 1.2- to 3.5-fold (mean result, 172.1±5.8, % of control value).

the upraise of blood serum atherogenicity.

beginning of treatment.

202 Current Trends in Atherogenesis

The presence or absence of serum atherogenicity at the baseline, as well as the extent of se‐ rum-induced intracellular cholesterol accumulation at the baseline, did not correlate with the following changes in IMT. However, the statistically significant correlation has been re‐ vealed between the changes in blood serum atherogenicity during the study and the changes in intima-media thickness of common carotid arteries (r=0.144, P=0.045 for the total study sample). In patients with initially non-atherogenic sera, the correlation between changes in atherogenicity and IMT was stronger (r=0.342, P=0.031). This correlation is ex‐ plained mainly by the arrival of serum atherogenicity during follow-up in a subgroup of placebo recipients with initially non-atherogenic sera; in them the correlation between in‐ crease of atherogenicity and IMT dynamics was the highest (r=0.517, P=0.034).. In patients with initially atherogenic sera, the correlation between changes in atherogenicity and IMT in total group did not reach statistical significance (r=0.147, P=0.067), but in Allicor-treated pa‐ tients in most of whom the decrease in serum atherogenicity was observed, the above pa‐ rameters correlated well (r=0.254, P=0.034).

There is a substantial experimental background to explain the possible mechanisms under‐ lying a direct anti-atherosclerotic action of Allicor. The components of garlic can regulate two main intracellular enzymes responsible for cholesterol intracellular metabolism. Garlic extract stimulates cholesteryl ester hydrolase and inhibits acetyl coenzyme A : cholesterol acyl transferase, thus diminishing intracellular content of cholesteryl esters [98]. Additional‐ ly, garlic extract inhibits cellular proliferative activity and the synthesis of connective tissue matrix components [98,99]. Allicor also possesses antioxidant activity and lowers LDL sus‐ ceptibility to oxidation [99]. Allicor prevents serum-induced cholesterol accumulation in cells cultured in the presence of patient's serum taken after single dose of Allicor adminis‐ tration; in other words, it reduces serum atherogenic potential [99]. In animal studies, garlicbased preparations inhibit the formation of neointimal thickening in cholesterol-fed rabbits [100]. So, it could be easily proposed that long-term Allicor treatment produced a direct anti‐ atherosclerotic effect due to the prevention of lipid deposition and depletion of cholesterol pool already accumulated in arterial wall.

Garlic contains a variety of organosulfur compounds, amino acids, vitamins and minerals [101]. Some of the sulfur-containing compounds such as allicin, ajoene, S-allylcysteine, Smethylcysteine, diallyl disulfide and sulfoxides may be responsible for antiatherosclerotic activity of garlic [98,100]. Many garlic-based products are present on the market now. As compared to other garlic preparations, dehydrated garlic powder is thought to retain the same ingredients as raw garlic, both water-soluble and organic-soluble, although the pro‐ portions and amounts of various constituents may differ significantly [102,103]. Allicor con‐ tains just garlic powder; on the other hand, it possesses a prolonged mode of action, as its antiatherogenic effect lasts for 12-16 hours after single dose administration [99]. So, Allicor differs greatly from other garlic-based preparations and may have considerable benefits in medicinal use.

ing additional amounts of biologically active polyphenols including resveratrol, genisteine and daidzeine that are claimed to produce some effects on atherosclerosis development. Karinat also contains additional amounts of β-carotene, α-tocopherol and ascorbic acid to

A randomized double-blinded placebo-controlled pilot clinical study on atherosclerotic ef‐ fect of Karinat was performed in healthy peri- and postmenopausal women to understand the risks and benefits of phytoestrogen therapy in relation to atherosclerosis progression. The primary endpoint was the annual rate of changes in common carotid artery intima-me‐ dia thickening, and the secondary endpoint was the dynamics of climacteric syndrome, that is monitored only in perimenopausal women. Table 6 demonstrates the effect of Karinat treatment on the dynamics of carotid atherosclerosis in postmenopausal women. In the pla‐ cebo group an increase in the average IMT of more than 100 µm per year was observed. Thus, the rate of the natural history of atherosclerosis in postmenopausal women is extreme‐ ly high: the average increase in IMT is 13% per year, and growth of atherosclerotic plaques

Number of participants 80 - 77 - IMT, μm +6 (85) p<0.05 +111 (91) p<0.02 Plaques, scores +0,21 (0,59) 0,009 +0,31 (0,55) <0,001

In the Karinat group a completely different picture was observed. The average IMT of caro‐ tid arteries was not changed (statistically insignificant increase of 6 µm per year, i.e. less than 1%). However, the progression of existing plaques by 27% per year was detected.

The results of quantitative measurements of the degree of atherosclerosis in the dynamics have shown that the use of phytoestrogen complex in postmenopausal women almost com‐ pletely suppresses the formation of new atherosclerotic lesions and 1.5-fold slows the pro‐

Thus, as in the AMAR trial Inflaminat caused regression of carotid atherosclerosis while Karinat prevented its development. It should be noted that the anti-atherosclerotic effects of drugs based on natural products are not inferior to the effects of such drugs as statins and calcium antagonists (Table 4). Thus, natural products can be considered as promising drugs

**Table 6.** Carotid IMT changes in 1-year Karinat pilot study on postmenopausal women

This review illustrates the use of cultured human arterial cells for:

**Karinat Р Placebo Р**

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provide the necessary daily intake of antioxidants

of 40% per year.

gression of existing lesions.

for anti-atherosclerotic therapy.

**10. Conclusion**

On the whole, the results of our study demonstrate that long-term treatment with time-re‐ leased garlic-based drug Allicor provides a direct anti-atherosclerotic effect on carotid athe‐ rosclerosis. Being the remedy of natural origin, Allicor is safe with the respect to adverse effects and allows even perpetual administration, which may be quite necessary for preven‐ tion and treatment of subclinical atherosclerosis. These results encouraged clinical trials of two other drugs based on natural products, including: Inflaminat, possessing anti-cytokine activity and the phytoestrogen-rich drug Karinat, designed for postmenopausal women.

Atherosclerosis is regarded as a pathological process with elements of local aseptic inflam‐ mation, while inflammatory cytokines play a role at every stage of atherosclerosis develop‐ ment [104-107]. In this regard, drugs with systemic anti-inflammatory action may be effective for the prevention of atherosclerosis. In our study, we investigated the atheroscle‐ rosis regression effect of natural drug Inflaminat based on calendula, elder and violet. These plants are widely used in herbal medicine as anti-inflammatory agents. In a pilot study of Inflaminat using a protocol similar to the AMAR study Inflaminat demonstrated atheroscle‐ rosis regression effects and statistically significant difference from the baseline as well as from placebo group (Table 5). Thus, Inflaminat possesses atherosclerosis regression effect in asymptomatic men.


**Table 5.** Carotid IMT changes in 1-year Inflaminat pilot study\* significant differences, p<0.05, Wilcoxon's signed ranked test;\*\*statistical significance of differences was estimated by Mann-Whitney U-test.

Atherosclerosis prevention in postmenopausal women is a striking problem, since modern medicine does not provide any effective approach. Hormone replacement therapy was re‐ jected as a tool for atherosclerosis prevention in women due to the negative results of recent studies – WHI, PEPI and HERS [108-113]. So, the development of novel approaches is highly demanded. Phytoestrogens are often regarded as a possible alternative to hormone replace‐ ment therapy, but practically nothing is known on their effects on atherosclerosis.

We screened many natural phytoestrogen-rich components for their antiatherogenic activity using an ex vivo test system [39,61,114-117]. The most promising of these compounds were: garlic powder, extract of grape seeds, green tea leafs and hop cones - all produced a signifi‐ cant antiatherogenic effect. On the basis of their combination, the novel isoflavonoid-rich di‐ etary supplement Karinat was developed. It produces the most efficient antiatherogenic effect in cell culture models and is characterized by improved phytoestrogen profile, provid‐ ing additional amounts of biologically active polyphenols including resveratrol, genisteine and daidzeine that are claimed to produce some effects on atherosclerosis development. Karinat also contains additional amounts of β-carotene, α-tocopherol and ascorbic acid to provide the necessary daily intake of antioxidants

A randomized double-blinded placebo-controlled pilot clinical study on atherosclerotic ef‐ fect of Karinat was performed in healthy peri- and postmenopausal women to understand the risks and benefits of phytoestrogen therapy in relation to atherosclerosis progression. The primary endpoint was the annual rate of changes in common carotid artery intima-me‐ dia thickening, and the secondary endpoint was the dynamics of climacteric syndrome, that is monitored only in perimenopausal women. Table 6 demonstrates the effect of Karinat treatment on the dynamics of carotid atherosclerosis in postmenopausal women. In the pla‐ cebo group an increase in the average IMT of more than 100 µm per year was observed. Thus, the rate of the natural history of atherosclerosis in postmenopausal women is extreme‐ ly high: the average increase in IMT is 13% per year, and growth of atherosclerotic plaques of 40% per year.


**Table 6.** Carotid IMT changes in 1-year Karinat pilot study on postmenopausal women

In the Karinat group a completely different picture was observed. The average IMT of caro‐ tid arteries was not changed (statistically insignificant increase of 6 µm per year, i.e. less than 1%). However, the progression of existing plaques by 27% per year was detected.

The results of quantitative measurements of the degree of atherosclerosis in the dynamics have shown that the use of phytoestrogen complex in postmenopausal women almost com‐ pletely suppresses the formation of new atherosclerotic lesions and 1.5-fold slows the pro‐ gression of existing lesions.

Thus, as in the AMAR trial Inflaminat caused regression of carotid atherosclerosis while Karinat prevented its development. It should be noted that the anti-atherosclerotic effects of drugs based on natural products are not inferior to the effects of such drugs as statins and calcium antagonists (Table 4). Thus, natural products can be considered as promising drugs for anti-atherosclerotic therapy.
