- Current Therapeutic Research Vol.58,No.12,December 1997 -

Multicenter Clinical Trial Of The Serum Lipid
Lowering Effects Of a Monascus Purpureus (Red Yeast) Rice Preparation
From Traditional Chinese Medicine

INTRODUCTION

Hyperlipidemia is a highly predictive risk factor for atherosclerosis, coronary artery disease, and cerebral vascular diseases. ^1-3 Regulating hyperlipidemia has proven to be effective in lowering the morbidity and mortality associated with coronary artery disease. ^3-5

Among the current lipid-lowering agents, hepatic hydroxy-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are effective in reducing total cholesterol (TC) and low-density lipoprotein (LDL) cholesterol. Nonetheless, the high cost of these drugs and their limited availability to the majority of the Chinese popultion have prompted Chinese medical investigators to search for alternative agents to lower serum lipids. Because traditional Chinese medicine, through centuries of empirical use, has produced an extensive library of active herbs, it is reasonable to investigate whether a lipid-lowering dietary supplement could be identified from this library. After an intensive investigation, Monascus purpureus (red yeast)rice was identified as an effective herb to lower serum cholesterol and triglycerides (TG) in animals, and its hypolipidemic effects were confirmed in pilot clinical studies. ^6-10

The M purpureus preparation is derived from a strain of M purpureus Went yeast (Xuezhingkang in Chinese ) that is prepared by a traditional rice fermentation method. Red Yeast rice has been used for centuries in China to make rice wine and to flavor foods. It was reported in the ancient Chinese pharmacopoeia, BenCaoGangMu-DanShiBuYi, which was published during the Ming Dynasty (1368-1644), ¹¹to promote blood circulation. Recent studies showed that M purpureus rice contains HMG-CoA reductase inhibitors that reduce the synthesis of cholesterol in the liver. ^6,12This herb also contains large quantities of unsaturated fatty acids (>125 mg/g M purpureus rice preparation), including monounsaturated fatty acids, diene-, triene-, tetraene-, and pentaene-fatty acids. Although the function of these unsaturated fatty acids is not known, they may heop reduce serum lipids. ¹³Other components include proteins, amino acids, saccharides, beta-sitosterol, campesterol, stigmasterol, isoflavone and its glycosides, saponin and sapogenin, and many trace elements.¹²

The lipid-lowering effects of M purpureus rice have been shown in several animal models of hyperlipidemia to inhibit and prevent increases in TC, LDL-cholesterol, and TG. ⁶For example, in rabbits fed a diet of 25% casein to induce endogenous hypercholesterolemia, treatment with M purpureus rice for 30 days at daily dosages of 0.4 and 0.8 g/kg significantly lowered serum TC concentration and the TC:high-density lipoprotein (HDL)-cholesterol ratio. ⁶In a second rabbit model in which hyperlipidemia was induced exogenously by an atherogenic diet, ⁶oral M purpureus rice preparation prevented increases in serum TC and TG concentrations and the TC: HDL-cholesterol ratio (P<0.05, compared with untreated hyperlipidemic controls). When hyperlipidemia was induced exogenously in quail by feeding an atherogenic diet that included 1% cholesterol, 14% lard, and 6% soybean oil, M purpureus rice preparation administered orally significantly reduced serum TC and TG concentrations. Acute and chronic animal toxicity studies further showed that M purpureus rice is well tolerated, even at doses several times higher than the effective therapeutic dose (manuscript in preparation).

In the present study, we demonstrated that a standardized M purpureus rice preparation reduced elevated serum cholesterol and TG, as compared with another herb, Jiaogulan (Gynostemma pentaphylla), which is believed to be an antihyperlipidemic agent in China.¹⁴


PATIENTS AND METHODS

Patients were excluded from the trial if they had any of the following during the last 6 months: myocardial infarction, stroke, severe trauma or major surgery, nephrotic syndrome, hypothyroidism, acute or chronic hepatobiliary disorders, diabetes mellitus, gout, allergies, or psychosis.

Patients who agreed to participate in this clinical trial were informed of the possible benefits and risks. Based on pretreatment TC and TG values, patients were prospectively randomized by a statistician into two unequal arms using a strategy of four-group randomization required by the Chinese Ministry of Public Health for clinical studies of traditional Chinese medicine. ¹⁵Groups A, C, and D were the treatment groups, and group B was the positive control group. The equality of the randomization distributions was verified by computer analysis.

Throughout the study, all patients were asked to maintain their normal lifestyles, including smoking, exercise, and dietary habits as advised by physicians 2 to 4 weeks before the trial treatment. All medications were allowed during the trial, except those that could affect serum lipids.

Hypolipidemic Efficacy
In the enrolled patients, serum lipids (TC, TG, and HDL cholesterol) were measured after fasting for at least 12 hours before enrollment and at the end of weeks 4 and 8 of the trial. Serum lipid measurements and other tests were performed in hospital laboratories; quality was routinely monitored by the Central Biochemistry Laboratory, Institute of Geriatrics of Beijing Hospital, as authorized by the Chinese Ministry of Public Health.

LDL cholesterol was calculated according to Friedewald equation, LDL cholesterol (mg/dL)=TC-(HDL cholesterol + TG/5); data from patients with TG measurements > 400 mg/dL were excluded. A ratio of non-HDL (TC - HDL = cholesterol): HDL cholesterol was also calculated, as an estimated risk factor for atherosclerosis.

The overall efficacy of M purpureus rice preparation was also assessed by an integrated analysis of the improvement in serum lipids. The criteria for the assessment of the overall clinical efficacy of M purpureus rice preparation are as follows¹⁶:

• Clinically Controlled
  Posttreatment serum lipids ration are within the normal ranges: TC, < 200 mg/dL, LDL cholesterol, < 130 mg/dL, TG, < 160 mg/dL, and HDL cholesterol, > 40 mg/dL for men or > 45 mg/dL for women.
• Highly Effective
  At least one of the following changes in serum lipids after treatment: TC reduced =20%, TG reduced =40%, HDL cholesterol increased =10 mg/dL, or the ratio of non-HDL: HDL cholesterol reduced=20 %.
• Effective
  At least one of the following changes in serum lipids after treatment: TC reduced =10% to < 20%, TG reduced =20% to < 40%, HDL cholesterol increased =4 mg/dL to < 10 mg/dL, or the ratio of non-HDL cholesterol: HDL cholesterol reduced =4 mg/dL to < 10 mg/dL, or the ratio of non-HDL cholesterol: HDL cholesterol reduced =10% to < 20%.
• Not Effective
  Posttreatment serum lipids unchanged or below the criteria for a rating of effective.

A total of 446 (89%) of the 502 enrolled patients completed the study; data from 56 could not be used for analysis for reasons of noncompliance and incomplete data collection. Two patients discontinued treatment because of exacerbation of their preexisting stomachache, and seven patients were determined to be noncompliant because of their inconsistent use of medication. The data for these nine patients were not used for final calculation. Missing serum lipid results for the rest of the 47 patients were found, and the data from those patients were not included from the final analysis. Table I shows baseline characteristics of the study population; the characteristics of the patients in the two groups were similar. The treatment group comprised 324 patients (188 men and 136 women, aged 56.0±0.50 years) and the positive control group comprised 122 patients (73 men and 49 women, aged 56.4±0.83 years). Patients in the two groups had hyperlipidemia for a similar number of years.

Among the 446 patients who completed the study, 345 (251 in the treatment group and 94 in the positive control group) had pretreatment TC=230 mg/dL (Table II). After 4 weeks of therapy with M purpureus rice preparation, TC was significantly decreased by 17.1% on average (-47.5 mg/dL, P< 0.001), whereas a 4.8% reduction (-13.2 mg/dL) was obtained in the positive control group (P< 0.001, between-group comparison). At 8 weeks, patients who received M purpureus treatment had an average reduction in TC of 22.7%(-62.8mg/dL, p<0.001) (Figure 1), whereas a 7.0% reduction (-18.9%mg/dL) was found in the positive control gound (p<0.001, between-group compaison).

Figure I. Percentage change(mean SE) in serum lipids after the 8-week Monascus purpureus (red yeast)rice preparation treatment (The difference in posttreatment and pretreatment serum lipids was calculated as a percentage of the pretreatment value for each patient.)*P<0.001,between-group comparison by Student's test. TC= total cholesterol; TG = triglycerides; LDL = low-density lipoprotein; ratio of non-HDL: HDL cholesterol = (TC-HDL cholesterol)÷HDL cholesterol; HDL = high-density lipoprotein.

Serum Low-Density Lipoprotein Cholesterol
The data for 321 patients (236 in the treatment group and 85 in the positive control group) with pretreatment serum LDL cholesterol=130 mg/dL and TG< 400 mg/dL are shown in Table II. Patients with TG> 400 mg/dL were excluded from the analysis because using the Friedewald equation to calculate LDL cholesterol cannot be used to provide useful information about such patients. After 4 weeks of treatment with M purpureus rice preparation, LDL cholesterol was reduced by 24.6% on average (-45.9 mg/dL, P< 0.001), with a mean reduction of 6.3% (-12.3 mg/dL) in the positive control group (P< 0.001, between-group comparison). After 8 weeks, LDL cholesterol was reduced by 30.9% (-58.2 mg/dL, P< 0.001) in the M purpureus-treated group; this reduction was significantly greater (P< 0.001) than that (-8.3%, -15.3 mg/dL) in the positive control group (Figure 1).

Serum Triglycerides
A total of 222 patients (157 in the treatment group and 65 in the positive control group) had pretreatment serum TG=200 mg/dL and < 400 mg/dL (Table II). Serum TG had decreased by an average of 19.8% (-54.0 mg/dL, P< 0.001) after 4 weeks of treatment with M purpureus rice preparation, as compared with a reduction of 9.2% (-24.6 mg/dL) in the positive control group (P=0.012, between-group comparison). At 8 weeks, average reductions of 34.1% (-94.1 mg/dL, P<0.001) and 12.8% (-34.7 mg/dL) were found in M purpureus-treated patients and control group, respectively (P< 0.001, between-group comparison) (Figure 1).

Serum High-Density Lipoprotein Cholesterol
Among the patients enrolled in this trial, 186 patients (129 in the treatment group and 57 in the positive control group) had low baseline serum HDL cholesterol (male < 40 mg/dL, female < 45 mg/dL) (Table II). After 4 weeks of treatment with M purpureus rice preparation, HDL cholesterol had increased by 12.8% on average (+4.5 mg/dL, P< 0.001), while an average 4.9% increase (+1.6 mg/dL) was found in the positive control group (P=0.002, between-group comparison). The 8-week treatment with M purpureus rice preparation resulted in a 19.9% increase (+7.2 mg/dL) in HDL cholesterol (P< 0.001), which was significantly greater (P< 0.001) than the 8.4% increase (+2.9 mg/dL) in the positive control group (Figure 1).

Ratio of Non-High-Density Lipoprotein: High-Density Lipoprotein Cholesterol
The ratio of non-HDL cholesterol (TC-HDL cholesterol) to HDL cholesterol was calculated for 345 patients (251 in the treatment group and 94 in the positive control group) who had pretreatment TC=230 mg/dL. Overall, patients in the M purpureus treatment group showed marked inprovement in this ratio (Table II) and a significant (P< 0.001) improvement in comparison with the positive control group. The 8-week treatment with M purpureus rice preparation resulted in a 34.5% decrease (-1.7) in the ratio (P< 0.001), which was significantly better (P< 0.001) than the 8.3% decrease (-0.5) in patients in the positive control group (Figure 1).

Integrated Analysis of Effects
We further analyzed the general efficacy of M purpureus rice preparation using a rating system detailed in Patients and Methods. As shown in Table II, there were 258 patients in the treatment group who achieved the criterion of clinically controlled (n=169) or highly effective (n=89), which resulted in a total highly effective rate of 79.6%. In the positive control group, 38 patients (31.1%) satisfied the same criteria. The total effective rate was obtained in 93.2% of patients in the treatment group, which was also significantly better (P< 0.001) than the same rating obtained in 50.8% of the positive control patients.

The actual decrease in LDL cholesterol also appeared to be dependent on the level of the pretreatment LDL cholesterol (Figure 2B). However, the percentage reduction of LDL cholesterol did not differ significantly (P=0.11) between the patients with pretreatment LDL cholesterol of 130 to 160 mg/dL (-22.4±7.2%) and pretreatment LDL cholesterol > 200 mg/dL (-34.6±2.1%).

The reduction in TG, both actual (mg/dL) and percentage reduction, was more marked when pretreatment TG were highly elevated (Figure 2C). For example, patients with pretreatment TG=300 mg/dL had the largest percentage drop (-40.1%, -152 mg/dL, P< 0.001) from pretreatment baselines compared with the decrease (-8.8%, -17 mg/dL) in those with pretreatment TG< 200 mg/dL (P< 0.001, comparing the subgroups).

Pretreatment HDL cholesterol also determined the percentage increase in this lipid (Figure 2D). In patients with HDL cholesterol > 45 mg/dL, M purpureus rice preparation therapy resulted in a minor 4.0% increase in HDL cholesterol (+1.81 mg/dL, P=0.041, compared with pretreatment baseline). In contrast, the percent increase in patients with pretreatment HDL cholesterol of 35 to 45 mg/dL was +16% (+6.3 mg/dL, P< 0.001, as compared with pertreatment baseline); in patients with pretreatment HDL cholesterol< 35 mg/dL, the increase was 25.1% (+7.9 mg/dL, P< 0.001, as compared with pretreatment baseline).

*Clinically Control = posttreatment serum lipid levels within normal ranges (total cholesterol [ TC ] <200 mg/dL, low-density lipoprotein cholesterol [ LDL cholesterol] <130 mg/dL, triglycerides [TG] <160 mg/dL, and high-density lipoprotein cholesterol [HDL cholesterol] >40 mg/dL for males and >45 mg/dL for females; Highly Effective =at least one of the following posttreatment changes in serum lipids: TC reduced =20%, TG reduced =40%, HDL cholesterol increased=10 mg/dL, or ratio of non-HDL: HDL cholesterol reduced =20%; Effective = at least one of the following posttreatment changes in serum lipids: TC reduced=10% to <20%, TG reduced =20% to <40%, HDL cholesterol increased =4 mg/dL to <10 mg/dL, or non-HDL cholesterol: HDL cholesterol reduced =10% to <20%; and Not Effective = posttreatment serum lipids unchanged or below the criteria for a rating of Effective.
Total Highly Effective rating obtained by adding the numbers of patients whose outcomes were rated Clinically Controlled or Highly Effective.

Total Effective rating obtained by adding the numbers of patients whose outcomes were rated Clinically Controlled, Highly Effective, or Effective.

Body Weight Reduction
The hypolipidemic effects of M purpureus rice preparation may be related to body weight changes because of dietary control. At 8 weeks, no significant differences in changes in body weight were found between the patients treated with M purpureus rice preparation (-1.40±0.28 kg) and positive controls (-0.91±0.15 kg). Regression analysis of changes in body weight and serum lipids did not reveal a correlation between these variables in either group.

Safety Assessment
Of the 324 patients who received 8 weeks of treatment with M purpureus rice preparation, 6 patients (1.9%) experienced heartburn, 3 (0.9%) flatulence in the stomach, and 1 (0.3) dizziness. These symptoms re solved without specific treatment, and the patients completed their trial treatment. Two patients (0.6%) withdrew from the trial due to exacerbation of their preexisting stomachache during treatment with M purpureus rice preparation. None of the 54 patients withdrawn from the trial developed any symptoms or medical conditions related to the trial treatment. No patients in either the treatment or positive control group had increased alanine aminotransferase twice the upper limit of normal (normal, < 40 IU/L) after the 8-week trial. The abnormal pretreatment electrocardiographic findings improved in 18 patients (5.6%) after M purpureus treatment. Serum creatine kinase (normal, < 200 IU/L) increased after 8 weeks in both groups: +31 IU/L (+46%) on average in the M purpureus rice preparation group and +24 IU/L (+39%) in the positive control group. In the treatment group, 1 patient (0.3%) had posttreatment serum creatine kinase approximately 2.5 times the upper limit of normal. There were, however, no significant differences in either pretreatment or posttreatment serum creatine kinase between the two groups.

DISCUSSION AND CONCLUSIONS

This single-masked clinical study involving patients from four clinical sites demonstrated that M purpureus rice preparation administered daily for 8 weeks was very effective in reducing serum cholesterol, with an average 22.7% reduction in TC and 30.9% in LDL cholesterol. The percentage reduction in TC and LDL cholesterol obtained with M purpureus rice preparation was independent of pertreatment levels, but the absolute reduction was greatest in those patients with baseline TC=300 mg/dL or LDL cholesterol > 200 mg/dL. Based on guidelines developed by the Chinese Ministry of Public Health, ¹⁶M purpureus rice preparation was effective in 93.2% of the patients and highly effective in 79.6% of the patients treated.

In addition to lowering TC and LDL cholesterol, this study showed that M purpureus rice preparation was effective in reducing serum TG in patients with hyperlipidemia. This TG-lowering effect was more evident when pretreatment TG were > 300 mg/dL.

There was also a 19.9% increase in HDL cholesterol in patients who received M purpureus rice preparation. This effect was also dependent on the pretreatment baseline, with an inverse relationship between the two variables. Lower pretreatment HDL cholesterol resulted in a greater increase in HDL cholesterol. Notably, the 34.5% decrease in the ratio of non-HDL cholesterol to HDL cholesterol after 8 weeks of treatment with M purpureus rice preparation suggests that there may be a reduced risk of atherosclerosis in patients receiving this therapy. Animal studies have demonstrated that atherosclerosis was significantly reduced in hyperlipidemic rabbits and quail after M purpureus rice treatment.⁶

The mechanism by which M purpureus rice preparation reduces serum TG and raises HDL cholesterol is not completely understood. This natural food product (original form available in the United States as cholestin3™ [Pharmanex, Inc., Simi Valley, California ]) does, however, contain many nutritional components, such as unsaturated fatty acids, sterols (betasitosterol, campesterol, stigmasterol), proteins, saccharides, isoflavone and its glycosides, saponin and sapogenin, and trace elements such as selenium and zinc, in addition to compounds that inhibit HMG-CoA reductase. ¹²It should be emphasized that the small quantity (< 14 mg/dL) of total structure-related HMG-CoA reductase inhibitors found in this natural dietary product cannot account for all the lipid-lowering effects of M purpureus rice. Decreased absorption of ingested lipids, reduced very-low-density lipoprotein cholesterol, and/or facilitated removal of very-low-density lipoprotein cholesterol are all events that may also contribute to a reduction in cholesterol and TG and an increase in HDL cholesterol. Interestingly, our data indicate that there was no complete correlation between any of the changes in patients' serum lipids and decreased body weight in either group.

Severe side effects with M purpureus rice treatment were rare, and the treatment was well tolerated in this study. Although mild side effects (ie, heartburn, flatulence, and dizziness) were found in a few patients, these symptoms resolved quickly. No changes in alanine aminotransferase were found after the 8-week treatment; mild increases in creatine kinase were found in both groups. Because of regulatory requirements mandated by the Chinese government,^15,16 it was not possible to include a placebo control group to establish whether the rise in creatine kinase was related to treatment. However, it is worth noting that in the EXCEL study,¹⁷ the placebo control group had an increase in creatine kinase similar to that seen in the group treated with mevinolin.

In summary, we suggest that M purpureus rice preparation is a highly effective and well-tolerated dietary supplement that can be used to regulate elevated serum cholesterol and TG. The reductions in serum TC, LDL cholesterol, and TG, and the increase in HDL cholesterol are achieved quickly and are clinically meaningful. M purpureus rice preparation may, therefore, enable people whose serum lipids are significantly elevated to maintain serum cholesterol and TG within a normal range.


Acknowledgments

This study was supported by WBL Peking University Biotech. Co. Ltd., Beijng, China. The authors thank Dr. David Chang for the statistical analyses he performed for this study.

References