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Ganoderma lucidum is a Chinese herbal medicine popular with cancer patients. Previous in vitro studies suggested that Ganoderma lucidum might impair hemostasis. In this prospective, randomized double-blind study, healthy volunteers received orally Ganoderma lucidum capsules 1.5 g (n = 20) or placebo (n = 20) daily for 4 wk. We monitored subjects before drug administration and at 4 and 8 wk thereafter by routine coagulation screen, fibrinogen concentration, von Willebrand ristocetin cofactor activity, platelet function analyzer PFA-100®, and thrombelastography. There were no significant between-group differences and all measurements remained within the normal range. Ganoderma lucidum ingestion over 4 wk was not associated with impairment of hemostasis.
The use of herbal medicine is increasing worldwide (1,2). Ganoderma lucidum (Ling-Zhi in Chinese) is a Chinese herb (3) that is rapidly gaining in popularity, particularly in patients with cancer (2), as it can improve immunological function (4), suppress tumor growth in vitro (5,6), and it is also a free radical scavenger (7). A survey in Hong Kong showed it to be the third-most common herbal medicine used by presurgical patients in Hong Kong (8). One of the concerns about Ganoderma lucidum use in the perioperative period is its potential adverse effect on hemostasis. Previous studies have shown that Ganoderma lucidum may impair hemostasis as a result of the presence of ganodermic acid S and adenosine-related compounds that may cause platelet inhibition (911). A protease with antithrombotic and fibrinolytic activity has been isolated from Ganoderma lucidum that competitively inhibits thrombin-fibrinogen binding (12). However, some of these studies used animal blood and all were in vitro studies. We have therefore designed this randomized, double-blind, placebo-controlled trial to evaluate the acute effects of Ganoderma lucidum on hemostasis
With Research Ethics Committee approval and informed written consent, healthy adult volunteers were allocated randomly to receive a single treatment period of 4 wk with Ganoderma lucidum (group L) or identical-looking placebo (group P). Subjects with known bleeding disorder or taking drugs affecting hemostasis or other herbal medication were excluded. Ganoderma lucidum was supplied as capsules (Greenvalley® Ltd., Shanghai, China), containing 500 mg active Ganoderma lucidum extract. Each subject took 1 capsule 3 times daily as recommended in the product package insert. All subjects had blood sampling at week 0, the fourth week, and the eighth week, when 15 mL whole blood was collected from an antecubital vein and subjected to the following tests:
In addition subjects also answered a questionnaire on bleeding symptoms before each blood sampling. Complete blood counts were performed on an automated cell counter (Gen-S®; Beckman-Coulter). PT and aPTT were done immediately after collection of blood samples and centrifugation at 3000 rpm for 10 min on an automated coagulometer (MDA-180®, Organon-Technika). Fibrinogen level was assayed by Clauss method using a semi-automated coagulometer (CobasFibro®; Roche, Switzerland). vWF:RCo activity was assayed in batches by agglutination of lyophilized platelets (Bio/Data Corporation, PA) in dilutions of test plasma, using a platelet aggregometer (Chrono-long Corporation, PA).
Recalcified TEG® was performed as described previously (13). All conventional TEG® variables including R-time, K-time, maximum amplitude, angle ( Samples for PFA-100® were collected in to 3.8% (0.129 M) buffered sodium citrate tubes (Vacutainer®; Becton Dickinson, Franklin Lakes, NJ). This was stored at room temperature and measurements were made within 1 h using 800 µL citrated whole blood with both collagen/epinephrine and collagen/adenosine-5'-diphosphate (ADP) cartridges, which contain a membrane coated with 2 µg of equine Type I collagen and 10 µg epinephrine bitartrate or 2 µg of equine Type I collagen and 50 µg ADP, respectively. All subjects and investigators involved in drug dispensing and hemostatic monitoring were blinded as to the study medication taken by the subjects.
Parametric data in the two groups were compared by unpaired Students t-test and nonparametric data were compared by Mann-Whitney U-test or Statistical analysis was performed using SAS System 8.02 (SAS Institute Inc., Cary, NC). A value of P < 0.05 was considered significant.
Forty volunteers were recruited (Table 1). No statistically significant between-group difference was detected in any of the hematology tests, vWF:RCo activity, or fibrinogen assays or in any TEG® variables or in PFA-100® closure times (Table 2).
The use of alternative and herbal medications preoperatively may have serious implications in the perioperative period (1416). Numerous herbal medications, including garlic, ginger, Salvia miltiorrhiza (Danshen), Ginkgo biloba, and others, have adverse hemostatic effects (17). Because previous investigations on the hemostatic effects of Ganoderma lucidum were either in vitro or animal studies and showed conflicting results (9,11,12,18), the clinical relevance of Ganoderma lucidum ingestion to impairment of hemostasis during surgery remains undefined. This is the first clinical trial to evaluate such a potential risk by using a prospective randomized, double-blind and placebo-controlled design. Hemostatic function was monitored by symptom checklist, routine coagulation screen and TEG® and PFA-100® in our study. TEG® has been reported to predict blood loss, mostly in cardiac surgery (19,20), but also in trauma patients (21) and in cirrhotic patients with variceal bleeding (22) and after renal biopsy (23). It is also useful in monitoring the effect of low molecular weight heparin (24), unlike PT/aPTT. However, because TEG® is insensitive to the effects of aspirin (25), we have supplemented TEG® with PFA-100®, which is primarily a platelet function monitor (26). The two hemostatic monitors we used in this study may not have detected all the possible effects of Ganoderma lucidum on hemostasis. Unlike laboratory platelet function tests, such as aggregometry and flow cytometry, our monitors are unable to delineate the mechanism of any detected disorder. Instead of using platelet-poor plasma (PT/aPTT) and platelet-rich plasma (aggregometry), our monitors use whole blood for measurement, and this may also account for the differences in result between this study and previous ones. The treatment and washout periods were arbitrarily set at 4 weeks. The concept of elimination half-life is less clear for herbal medications than for synthetic chemical medicines, as herbal medications always contain numerous different compounds. The effects of herbal medications are also generally more gradual. In our study, we have based the treatment and washout period on the turnover period of platelets and coagulation factors in the human body. Platelets have a lifespan of 710 days whereas the coagulation factors have varied half-lives, the longest being those of Factor XIII, fibrinogen, and prothrombin, which have half-lives of approximately 36 days. By having a 4-week treatment and washout period, all effects of Ganoderma lucidum on platelets and coagulation factors should have been fully evident at the time of measurement. There are a number of limitations in our study. First, we have not demonstrated directly the absence of perioperative bleeding in patients taking Ganoderma lucidum. Second, we have only used a standard dose in this study; the effect of Ganoderma lucidum at larger doses may be different. Finally, our study was conducted in healthy volunteers and may not apply to many surgical patients who may have coexisting coagulopathies or be taking other medications that affect hemostasis. We conclude that Ganoderma lucidum (Ling-Zhi capsule Greenvalley®) at a dose of 1.5 g daily is not associated with gross impairment of platelet and global hemostatic function and is unlikely to increase risk of bleeding in individuals who do not have other conditions that may interfere with hemostasis. We thank Shanghai Greenvalley Holding Ltd who supplied both the Greenvally® LZ capsule and placebo used in this study. We also thank Mr Alan Chit, Executive Director of HPC Healthcare & Pharma Consulting International Ltd. who provided useful information concerning Ganoderma lucidum and Ms SF Tsang and Jeff Man for technical assistance. Apart from the sponsorship for drug supply, no other personal or departmental profit is related to the study.
Supported, in part, by a research grant from the Small Project Funding Programme of the University of Hong Kong (Grant No 10204353). Accepted for publication December 14, 2004.
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