Cordyceps is a mushroom traditionally used to treat sexual dysfunction and
fertility in Chinese medicine, as well as a general sexual tonic and
libido/performance enhancer. It has become a prized commodity. In China, it is
used as an aphrodisiac and all-round energy booster. In 1993, Chinese athletes
broke world records at their national games, which their trainer put down to
eating the caterpillar fungus (pdf). Kira jari is now going global. You can even
buy it in the UK.
Cordyceps sinensis belongs to a genus of more than 400 species of Ascomycete
(sac fungi) found worldwide. It is a black, blade-shaped fungus found primarily
in the high altitudes of the Tibetan plateau in China that parasites moth
caterpillars. In the fall, the fungal mycelia infect the caterpillar, which then
kills it by early summer of the following year, releasing spores from the
fruiting body (the stroma). The wild form of C. sinensis is rare and expensive;
consequently, a strain isolated from the wild form (Cs-4, or Paecilomyces
hepiali Chen) is cultivated industrially and more commonly used. Issues of
substitution with other species and contamination have been described.
Tibetan history records the first uses of yartsa gunbu in the 15th century.
Cordyceps is considered to be derived from the Latin cord (club), ceps (head),
and sinesis (from China).
The fruiting body and attached mycelium of cordyceps have been used in Chinese
culture and in traditional Chinese medicine for centuries. Cordyceps is valued
for its activity in restoring energy, promoting longevity, and improving quality
of life.
The nucleosides adenine, adenosine, uracil, uridine, guanidine, guanosine,
hypoxanthine, inosine, thymine, thymidine, and deoxyuridine are the major
component of cordyceps and can be used as a species marker. Fresh, natural
cordyceps contain a lower content of nucleosides than dry, processed, or
cultured cordyceps.
Other classes of constituents found in wild C. sinensis include the following:
proteins, peptides, all essential amino acids, and polyamines; saccharides and
sugar derivatives; sterols; fatty acids and other organic acids; vitamins
(including B 1 , B 2 , B 12 , E, and K); and inorganic elements. Cordycepin and
other adenosine derivatives, ergosterol, mannitol, cordyheptapeptide A, and
several other unique compounds have been identified using thin layer and gas
chromatography, high-performance liquid chromatography, and capillary
electrophoresis. Water, ethanol, methanol, and ethyl acetate extracts have been
described for the whole fungus and mycelium, as well as for other parts of the
fungus.
Traditionally, cordyceps has been used in the elderly population to improve
weakness, impotence, and fatigue associated with aging. Clinical studies have
been conducted among elderly subjects; however, the methodology of such studies
is often poorly documented. Improvements in self-reported symptoms have been
described, as have increases in red blood cell superoxide dismutase activity and
decreases in malondialdehyde levels. Other antioxidant effects, hydroxyl radical
scavenging activity, and decreases in lipid peroxidation are thought to be
responsible for the antiaging effects, as well as effects on the adrenergic and
dopamine systems. Increases in learning and memory have been shown in
experiments in aged mice.
Numerous in vitro and animal experiments have been conducted on aqueous and
ethanol extracts of cordyceps, as well as with cordycepin and oxypiperazines
extracted from the mycelium. The extracts enhanced cytokine activity and induced
cell cycle arrest and apoptosis, thereby reducing tumor cell proliferation and
enhancing survival times.
Limited clinical studies report subjective improvement of symptoms, increased
tolerance of radiation and chemotherapy (possibly caused by enhanced immune
function), and reduction in tumor size with coadministration of cordyceps.
Cordyceps has a long history of traditional medicinal use in heart disease.
Adenosine and other nucleosides are thought to be responsible for the effects
seen in animal studies. A vasodilatory action has been reported in anesthetized
dogs, and hypotensive and vaso-relaxant effects have been demonstrated in rats.
Reduced heart rate and restoration from arrhythmias have also been shown in
animals. Long-term, open-label clinical studies in cardiac failure have
described cordyceps' effect in improving cardiac function, arrhythmias, and
overall quality of life, but are yet to be substantiated by large, high-quality
clinical trials.
Fibrinolytic action of a cordyceps extract has been shown in vitro on bovine and
human serum. Platelet aggregation has been inhibited in rabbits and in human
platelets in vitro. A positive effect on hyperlipidemia has also been reported
in aqueous extracts of cordyceps.
Animal studies suggest cordyceps, particularly the polysaccharide extracts,
decreases blood glucose levels by improving glucose metabolism and enhancing
insulin sensitivity. Few clinical trials exist; however, 1 small (N = 20),
randomized trial found that taking C. sinensis 3 g daily improved the blood
sugar profile over placebo.
Hepatoprotective effects of cordyceps extracts have been demonstrated in animal
models. Open-label clinical studies conducted in patients with active hepatitis
and posthepatic cirrhosis reported improvements in liver function tests.
Aside from limited data from clinical studies conducted in renal transplant
recipients and chronic hepatitis patients, the majority of studies have been
conducted in vitro and in vivo using mice or rats and were directed at
elucidating the mechanism of action for observed effects on the immune
system.Different fractions of cordyceps extracts (either aqueous or ethanol
based) appear to have different effects and, therefore, an immune-modulator
function for cordyceps has been proposed. The effects of cordycepin and
cordysinocan have been similarly evaluated.
Tests in animals, such as the mouse swim test, generally showed increased time
to exhaustion. Unpublished data on studies in elderly volunteers revealed
increased energy levels and oxygen-carrying capacity following 6 weeks of
cordyceps treatment over placebo. However, small, randomized, double-blind
clinical trials in healthy volunteers and in athletes reported no effect on
aerobic capacity, endurance, or performance. In 3 of these clinical trials,
cordyceps was used in conjunction with yohimbe or Rhodiola rosea extracts, but
no difference over placebo was found. In another clinical trial, cordyceps 3.15
g (as Cs-4) taken daily for 5 weeks had no effect compared with placebo.
Experiments in castrated rats showed a mild effect on sexual function. Decreases
in erection and mount latency were demonstrated, but no effect on ejaculation
latency was found; however, action on steroidogenesis and testosterone have been
shown. In clinical studies in elderly populations, improved sexual drive and
virility were reported.
One report of hypersensitivity with use of cordyceps exists. Mild GI discomfort,
including diarrhea, dry mouth, and nausea, has been reported in clinical
studies. Two cases of lead poisoning associated with cordyceps have been
reported, in which the lead content of the preparations was determined to be
particularly high. Plasma lead levels returned to normal upon cessation of
product consumption. In a study conducted in children with asthma, a combination
preparation containing cordyceps did not affect blood cell counts or renal or
liver function tests.
Cordyceps can reduce HcG and cAMP-stimulated steroidogenesis (via PKA and
possibly inhibiting P450scc by 30%, the enzyme that converts cholesterol to
pregnenolone).This same study showed that Cordyceps did not reduce testosterone
production when coincubated with androstenedione or pregnenolone, suggesting it
does not influence enzymes in the later portion of steroidogenesis.
Interestingly, this study also showed that Cordyceps was able to inhibit
Forskolin-induced steroidogenesis, which is cAMP-induced and how the herb Coleus
forskohlii increases testosterone. This inhibition of testosterone synthesis
stimulated by cAMP and HcG has been noted elsewhere, and inhibition of PKA
abolishes the effects of Cordyceps.
Cordyceps appears to increase testosterone synthesis in rats, and has multiple
compounds that could do this (protein fragments, Cordycepin); the protein
fragments appear to be biologically relevant, as 40mg/kg Cordycepin ingested
orally didn't do anything to testosterone in mice yet 0.2mg/kg whole Cordyceps
did. Cordyceps may possess testosterone regulatory properties, rather than blind
spiking of testosterone.
Cordyceps Militaris supplementation was shown to increase estradiol levels in
rats fed 1% or 5% of their diet as the mycelium, and although a significant
spike was seen 2 weeks after supplementation (from 30pg/mL to the 60-70 range),
it declined to baseline at 4 weeks and remained insignificantly different from
control.
