Cordyceps has been used to treat conditions including respiration and pulmonary diseases; renal, liver, and cardiovascular diseases; hyposexuality; and hyperlipidemia. It is also used in the treatment of immune disorders and as an adjunct to modern cancer therapies (chemotherapy, radiation treatment and surgery). Cordyceps is believed by many, particularly in and around Tibet (its place of origin), to be a remedy for weakness and fatigue, and it is often used as an overall rejuvenator for increased energy while recovering from a serious illness. Many also believe it to be a treatment for impotence, acting as an aphrodisiac in both men and women. Cordyceps is often prescribed for the elderly to ease general aches and pains. TCM practitioners also recommend the regular use of Cordyceps to strengthen the body’s resistance to infections, such as colds and flus, and to generally improve the homeostasis of the patient. Traditionally, Cordyceps has most often been used in the treatment of health issues related to or stemming from the kidneys and the lungs. For example, it is used to ease a range of respiratory ailments: cough and phlegm, shortness of breath, bronchial discomfort, chronic obstructive pulmonary disease (COPD), and asthma. Modern science is attempting to confirm the efficacy of Cordyceps for most of its traditional uses; however, most medical studies regarding its efficacy remain incomplete.
Today in the West, Cordyceps is most widely used by two groups of people: athletes and the elderly. The use of Cordyceps by athletes stems from publicity surrounding the performance exhibited by the Chinese Women’s Track and Field team at the Chinese National games in 1993. In this competition, 9 world records were broken by substantial margins. At first, governing sports authorities suspected that a performance-enhancing drug had been used, but the team’s coach attributed their success to Cordyceps. Research has shown that the use of Cordyceps results in an increase of cellular ATP. An increase in cellular ATP results in an increase in useful energy. This is in contrast to the perceived increase in energy that occurs from the use of CNS stimulants, such as caffeine, ephedrine, and amphetamines, which ultimately results in an energy deficiency. However, it should be noted that in a recent study with highly trained professional athletes, C. sinensis was shown to have no appreciable effect on increasing performance in this group of people. It is conceivable that these athletes were already performing to the limit of their potential and little increase in performance could be achieved through chemical or herbal supplementation. We are not aware of any test that has been conducted showing a difference in the energy increase potential between highly trained athletes and normal healthy adults using Cordyceps.
Inhabitants in the high mountains of Tibet and Nepal consume Cordyceps, claiming that it gives them energy and offsets the symptoms of altitude sickness. The proposed reason for the alleged increase in energy is an increase in cellular ATP, as previously mentioned; likewise, increased oxygen availability has been posited as the primary agent in combating the effects of altitude sickness.
B. Preclinical and Clinical Data
Therapeutic applications of Cordyceps and its extracts are hypothesized to be centered primarily on the key effects of increased oxygen utilization increased ATP production and the stabilization of blood sugar metabolism. The presence of adenosine, cordycepin, and cordycepic acid [d-mannitol]; polysaccharides; vitamins; and trace elements may be, at least partially, the cause for such effects. Due to the historically high cost of the fungus and the only recently developed methods for artificial cultivation, preclinical and clinical trials of Cordyceps and its extracts are still relatively new endeavors. Earlier trials, although few in number, have set the precedent from which modern trials are building, expanding, and cementing our understanding of Cordyceps.
A possibly valuable therapeutic application of Cordyceps is its potential as a treatment for cancer, as well as an adjunct to chemotherapy, radiation, and other conventional and traditional cancer treatments.
1. Animal Studies
The survival time of mice inoculated with murine B16 melanoma cells and treated with a combination of water extracts from C. sinensis and the chemotherapy agent, methotrexate, has been shown to be significantly longer than the survival time of either the untreated control group or those treated with methotrexate alone, indicating that some water extracts of C. sinensis may be beneficial in the prevention of tumor metastasis.
2. Clinical Trials
Clinical studies have been conducted in China and Japan involving cancer patients, yielding positive results. In one study of 50 patients with lung cancer who were administered C. sinensis at 6 grams per day, in conjunction with chemotherapy, tumors were reduced in size in 46% of the patients studied. A trial involving cancer patients with several different types of tumors found that C. sinensis, taken over a 2-month period at 6 g per day, improved subjective symptoms in the majority of patients. White blood cell counts were kept at 3000 per cubic millimeter or higher, and even with radiation or chemotherapy, other immunological parameters showed no significant change, whereas tumor size was significantly reduced in approximately half of the patients observed, indicating an improved tolerance for radiation and/ or chemotherapy. A serious side effect to the use of conventional cancer chemotherapy and radiation therapy is the suppression of the patient’s immune system. The use of C. sinensis in combination with conventional chemotherapy appears to have an immunostimulatory effect, which enhances the effectiveness of conventional chemotherapy by balancing its side effects. The belief in the efficacy of C. sinensis against cancer is widespread in the Orient, and many cancer patients in Japan, Korea, and China are taking Cordyceps or some other mushroom-derived immunomodulator (such as PSK, PSP, Lentinan, AHCC, heteropolysaccharide complex formula [Immune Assist™], and arabinoxylanes [MGN3™]) while undergoing conventional treatment.
3. Immunomodulating Effects
The immune-enhancing effects of C. sinensis have been alluded to in the above discussions. It is of interest to note that the fungus that produces the immunosuppressive drug cyclosporin, Tolypocladium inflatum, was discovered in 1996 to be the asexual stage of yet another Cordyceps species, C. subsessilus. Thus, the same genus of fungus that was used for centuries to provide immune stimulation was now known to provide an immune suppressant that is valuable in organ transplantation surgery. Other such experiments demonstrating both inhibiting as well as potentiating effects of Cordyceps are controversial, and the effects observed are possibly the result of differing experimental conditions and variables. However, with such evidence of a possibly bi-directional immune-modulating effect, further research is in order. Although the drug cyclosporin has enabled some advances in medicine by facilitating the transplant of organs, there has been a drawback to its use. The high toxicity of cyclosporin has caused many patients to suffer from serious kidney damage related to the use of the drug. In 1995, a study was undertaken in China in which 69 kidney transplant patients were given either cyclosporin alone or in conjunction with C. sinensis, at 3 grams per day. After 15 days it was clearly evident that the group receiving C. sinensis in addition to cyclosporin had a much lower incidence of kidney damage than the group receiving only cyclosporin, as measured by the levels of urinary NAG, serum creatinine, and blood urea nitrate.
4. Kidney Ailments
Traditional views of the Cordyceps species held that its consumption strengthened the kidneys. Studies have shown that much of the kidney-enhancing potential of Cordyceps stems from its ability to increase 17-hydroxy-corticosteroid and 17-ketosteroid levels in the body. Chronic renal failure is a serious disease, one often affecting the elderly. In a study among 51 patients suffering from chronic renal failure, it was found that the administration of 3–5 grams per day of C. sinensis significantly improved both kidney function and overall immune function of treated patients, compared to the untreated control group. Patients with chronic renal failure or reduced kidney function often suffer from hypertension, proteinuria, and anemia. In a study with such patients, it was found that after one month on C. sinensis, a 15% reduction in blood pressure was observed. Urinary protein was also reduced. Additionally, increases in superoxide dismutase (SOD) were seen. The increase in SOD, coupled with an observed decrease in serum lipoperoxide, suggests an increase in the oxygen-free radical scavenging capacity, resulting in reduced oxidative cellular damage. In another human clinical study, 57 patients with gentamicin-induced kidney damage were either treated with 4.5 grams of Cordyceps per day or by other more conventional methods. After 6 days, the group that received Cordyceps had recovered 89% of their normal kidney function, whereas the control group had recovered only 45% of normal kidney function. The time-to-recovery was also significantly shorter in the Cordyceps group when compared to the control group.
5. Hypoglycemic Effect
Another area of particular interest is the effect of Cordyceps spp. on the blood glucose metabolism system. Cordyceps sinensis has been tested in animal and human trials to investigate its potential as an agent in blood sugar regulation. In one randomized trial, 95% of patients treated with 3 grams per day of C. sinensis saw improvement in their blood sugar profiles, whereas the control group showed only a 54% improvement with treatment by other methods. For more details please log on to our website www.irissherbals.com
6. Lung Ailments
Chinese medicine has characterized C. sinensis as a guardian of respiratory health for more than a thousand years. There have been trials in humans using Cordyceps spp. to treat many respiratory illnesses, including asthma, COPD, and bronchitis, either alone or as an adjunct to standard antibiotic therapy, and in many studies that have been conducted, it appears to be useful for all of these conditions. Much of its reputation for protecting the lungs is believed to stem from its ability to promote enhanced oxygen utilization efficacy. In environments lacking sufficient oxygen, mice treated with Cordyceps were able to survive up to three times longer than those left untreated, demonstrating a more efficient utilization of the available oxygen. This provides support for the long history of Cordyceps use in preventing and treating altitude sickness. Such efficacy alludes to the use of Cordyceps as an effective treatment for bronchitis, asthma, and COPD. Extracts of C. sinensis have been shown to inhibit tracheal contractions, which is especially important in asthma patients because it allows for increased airflow to the lungs. In addition, its anti-inflammatory properties may prove to bring further relief to asthma patients whose airways become obstructed due to an allergic reaction resulting in the swelling of the bronchial pathways. In an unpublished clinical trial conducted at the Beijing Medical University involving 50 asthma patients, symptoms among the group treated with Cordyceps were reduced by 81.3% within an average of 5 days, whereas among those treated with conventional antihistamines, the rate of symptom reduction averaged only 61.1%, and it took an average of 9 days for symptoms to subside.
Cordyceps is also a medication used in stabilizing the heartbeat and correcting heart arrhythmias in China. Although the exact mechanism responsible for the reputation of Cordyceps with regard to controlling arrhythmias is not completely understood, it is thought to be at least partially due to the presence of adenosine, of which Cordyceps often has a significant quantity, along with deoxy-adenosine, related adenosine-type nucleotides, and other free nucleosides. It has been shown that these compounds have an effect on coronary and cerebral circulation. Although no single drug or herb is equally effective in all patients, it appears rare for a patient’s arrhythmia to remain unaffected by the addition of Cordyceps to the treatment regimen. Cordyceps has been used traditionally to treat patients with heart disease and those recovering from stroke. In studies of patients suffering from chronic heart failure, the long-term administration of Cordyceps, in conjunction with conventional treatments—that is, digoxin, hydrochlorothiaside, dopamine, and dobutamine, promoted an increase in the overall quality of life. This included general physical condition, mental health, sexual drive, and cardiac function, compared to the control group.
Another area of considerable research interest is the relationship between Cordyceps and liver function. Cordyceps has been shown in nearly all such studies to increase the efficient functioning of the liver. For example, in the Orient today, Cordyceps is commonly used as an adjunct in the treatment of chronic hepatitis B and C. In one study, Cordyceps extract was used in combination with several other medicinal mushroom extracts as an adjunct to lamivudine, for the treatment of hepatitis B. Lamivudine is a common antiviral drug used in the treatment of hepatitis. In this study, the group receiving Cordyceps along with other medicinal mushroom extracts had much better results, in a shorter period of time than the control group, who received only lamivudine. In another study using 22 patients who were diagnosed with posthepatic cirrhosis, after 3 months of consuming 6–9 grams of Cordyceps per day, each patient showed improvements in liver function tests.
Although hypercholesterolemia is not typically considered a disease, it is a clear indicator of metabolism dysfunction and an indicator of increased cardiovascular risk. In both human and animal studies, the administration of Cordyceps has been associated with cholesterol and triglyceride reduction and an increase in the ratio of HDL to LDL cholesterol. Whether the causative mechanism for this lipid-balancing effect is through blood sugar stabilization, from enhancing liver function, or due to some other as yet unknown cause, remains to be seen.
10.Treatment for Male/Female
Cordyceps has been used for centuries in TCM to treat male and female sexual dysfunction, such as hypolibidinism and impotence. Preclinical data on the effects of C. sinensis on mice showed sex-steroid-like effects. Human clinical trials have similarly demonstrated the effectiveness of Cordyceps in combating decreased sex drive and virility.
11.Use Against HIV/AIDS
A Cordyceps-containing formula, Immune Assist 24-7™, has recently come into popularity through- out West Africa for use in treating HIV infections and other immune-deficient states. This American- made product has been approved as a complementary medicine by the regulatory authorities in a number of African countries and is currently being stocked in most hospitals, clinics, and pharmacies throughout the region and is quite popular with both the doctors and the patients due to its low toxicity and cost when compared to the other antiretroviral drug options.
Many species of Cordyceps and other entomopathogenic fungi have been mentioned in scientific discourse in relation to their potential as biological-control agents.
There is observational evidence by these authors that the alteration of the body’s blood glucose metabolism in patients consuming Cordyceps often results in the reduction of oral or injected antidiabetic medications. It is also posited that the naturally occurring antiretroviral compounds found in Cordyceps (e.g., 2′3′-dideoxyadenosine, which is found in C. sinensis and is marketed as a major anti-HIV drug under the name Videx and Didanosine, as well as 3′-deoxy- adenosine, which has the same or at least similar activity) could result in increased effectiveness or decreased dosage requirements for patients undergoing concurrent therapy with other antiretroviral drugs. Caution should be exercised in these patients, especially considering the newer, more potent hybrid strains of Cordyceps being developed and the targeted medicinal compounds being selectively cultivated. Many antiretroviral drugs currently on the market are considerably toxic, and it is hoped that the incorporation of Cordyceps into the treatment regimen of those patients undergoing such therapy might result in a reduction of some of these more toxic synthetic drugs, while sacrificing none of their efficacy. Although no detrimental drug interactions have yet been noted in the scientific literature, caution is advised, as both the fields of pharmaceutical discovery and Cordyceps cultivation are rapidly expanding. As with any substance of considerable bioactivity, some drug interaction is always a possibility.
Adverse Side Effects
Very few toxic side effects have been demonstrated with Cordyceps use, although a very small number of people may experience dry mouth, nausea, or diarrhea. One study reported that a patient had developed a systemic allergic reaction after taking a strain of Cordyceps called Cs-4; however, this type of reaction is not common. There is little published data on the use of Cordyceps in pregnant or lactating women, or in very young children, and appropriate precautions should be taken with these types of patients.
Cordyceps has proven to be a nontoxic fungal substance with wide-ranging physical and chemical effects on the body. No human toxicity has been reported, and animal models failed to find an LD50 (median lethal dose) injected i.p. in mice at up to 80 g/kg per day, with no fatalities after 7 days.1,3 Given by mouth to rabbits for 3 months, at 10 g/kg per day (n = 6), no abnormalities were seen from blood tests or in kidney or liver function.62
When a natural product such as Cordyceps has such a long history of use, it seems logical that there is quite likely some truth behind the myths. Our challenge in the modern age is to scientifically unravel the many claims and conflicts. With Cordyceps this challenge has been greater than with many other herbals due to the enormous cost and scarcity of the material. We are fortunate that we live in an age of such rapidly expanding biotechnological progress, for now we have ways at our disposal to produce Cordyceps in large enough volume and at a low enough cost that research becomes possible to nearly anyone interested in looking at this unique organism. As time passes, we may find that this once rare fungal species may hold the key to controlling some of our more difficult-to-manage diseases. It is clear from our studies that we know only a little of the wonders of these strange Cordyceps creatures. Cordyceps still has many secrets in store for us. More research is needed on these and other species of medicinal mushrooms.