Pharmacokinetics of adenosine and cordycepin, a bioactive constituent of Cordyceps sinensis in rat

Accounting for the delay in the transition from acute to chronic pain: axonal and nuclear mechanisms

Acute insults produce hyperalgesic priming, a neuroplastic change in nociceptors that markedly prolongs inflammatory mediator-induced hyperalgesia. After an acute initiating insult, there is a 72 h delay to the onset of priming, for which the underlying mechanism is unknown. We hypothesized that the delay is due to the time required for a signal to travel from the peripheral terminal to the cell body followed by a return signal to the peripheral terminal. We report that when an inducer of hyperalgesic priming (monocyte chemotactic protein 1) is administered at the spinal cord of Sprague Dawley rats, priming is detected at the peripheral terminal with a delay significantly shorter than when applied peripherally. Spinally induced priming is detected not only when prostaglandin E2 (PGE2) is presented to the peripheral nociceptor terminals, but also when it is presented intrathecally to the central terminals in the spinal cord. Furthermore, when an inducer of priming is administered in the paw, priming can be detected in spinal cord (as prolonged hyperalgesia induced by intrathecal PGE2), but only when the mechanical stimulus is presented to the paw on the side where the priming inducer was administered. Both spinally and peripherally induced priming is prevented by intrathecal oligodeoxynucleotide antisense to the nuclear transcription factor CREB mRNA. Finally, the inhibitor of protein translation reversed hyperalgesic priming only when injected at the site where PGE2 was administered, suggesting that the signal transmitted from the cell body to the peripheral terminal is not a newly translated protein, but possibly a newly expressed mRNA.

Antagonistic interaction between cordyceps sinensis and exercise on protection in fulminant hepatic failure

Herb supplements are widely used by Asian athletes; however, there are no studies evaluated the co-effects of exercise and herb supplements on hepatic failure. In this study, D-GalN/LPS-induced fulminant hepatic failure was used to examine whether there are synergistic or antagonistic effects of exercise and Cordyceps sinensis (CS). Mice were randomly divided into eight groups: control, swimming exercise for four weeks, D-GalN/LPS challenge, swimming exercise plus D-GalN/LPS, 20 mg/kg or 40 mg/kg CS pretreated for four weeks plus D-GalN/LPS, and swimming exercise combined with 20 mg/kg or 40 mg/kg CS pretreatment plus D-GalN/LPS. Either exercise or 40 mg/kg CS pretreatment alone significantly decreased D-GalN/LPS-induced TNF-α, AST, NO, apoptotic-related proteins, and hepatocyte apoptosis. Exercise or 40 mg/kg CS alone increased the IL-10 and D-GalN/LPS-suppressed Superoxide Dismutase (SOD) level. However, no protective or worse effect was observed in the mice treated with exercise preconditioning combined 40 mg/kg CS compared to those receive exercise alone or CS alone. TNF-α, AST, NO level, caspase-3 activity, and hepatocytes apoptosis were not significantly different in the exercise combined with 40 mg/kg CS compared to mice challenged with D-GalN/LPS. The IL-10 level was significantly decreased after D-GalN/LPS stimulation in the mice received exercise combined with 40 mg/kg CS, indicating the combination strongly reduced the anti-inflammatory effect. In summary, preconditioning exercise or CS pretreatment alone can protect mice from septic liver damage, but in contrast, the combination of exercise and CS does not produce any benefit. The antagonistic interactions between exercise and CS imply taking CS is not recommended for people who undertake regular exercise.

Inhibition of adenosine deaminase (ADA)-mediated metabolism of cordycepin by natural substances

Cordycepin, which is an analogue of a nucleoside adenosine, exhibits a wide variety of pharmacological activities including anticancer effects. In this study, ADA1- and ADA2-expressing HEK293 cells were established to determine the major ADA isoform responsible for the deamination of cordycepin. While the metabolic rate of cordycepin deamination was similar between ADA2-expressing and Mock cells, extensive metabolism of cordycepin was observed in the ADA1-expressing cells with K_m and V_max values of 54.9 μmol/L and 45.8 nmole/min/mg protein. Among five natural substances tested in this study (kaempferol, quercetin, myricetin, naringenin, and naringin), naringin strongly inhibited the deamination of cordycepin with K_i values of 58.8 μmol/L in mouse erythrocytes and 168.3 μmol/L in human erythrocytes. A treatment of Jurkat cells with a combination of cordycepin and naringin showed significant cytotoxicity. Our in silico study suggests that not only small molecules such as adenosine derivatives but also bulky molecules like naringin can be a potent ADA1 inhibitor for the clinical usage.

Effects of cordycepin on HepG2 and EA.hy926 cells: Potential antiproliferative, antimetastatic and anti-angiogenic effects on hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a hypervascular tumor and accumulating evidence suggests that angiogenesis plays an important role in HCC development. Cordycepin, also known as 3′-deoxyadenosine, is a derivative of adenosine, and numerous cellular enzymes cannot differentiate the two. The aim of the present study was to determine whether cordycepin regulates proliferation, migration and angiogenesis in a human umbilical vein endothelial cell line (EA.hy926) and in a hepatocellular carcinoma cell line (HepG2). MTT was used to assess cell proliferation. Apoptosis was analyzed by flow cytometry (propidium iodide staining). Transwell and wound healing assays were used to analyze the migration and invasion of HepG2 and EA.hy926 cells. Angiogenesis in EA.hy926 cells was assessed using a tube formation assay. Cordycepin strongly suppressed HepG2 and EA.hy926 cell proliferation in a dose- and time-dependent manner. Cordycepin induced EA.hy926 cell apoptosis in a dose-dependent manner (2,000 μg/ml: 50.20±1.55% vs. 0 μg/ml: 2.62±0.19%; P<0.01). Cordycepin inhibited EA.hy926 cell migration (percentage of wound healing area, 2,000 μg/ml: 3.45±0.29% vs. 0 μg/ml: 85.48±0.84%; P<0.05), as well as tube formation (total length of tubular structure, 1,000 μg/ml: 107±39 μm vs. 0 μg/ml: 936±56 μm; P<0.05). Cordycepin also efficiently inhibited HepG2 cell invasion and migration. High-performance liquid chromatography analysis of the cytosol from EA.hy926 cells showed that cordycepin was stable for 3 h. In conclusion, cordycepin not only inhibited human HepG2 cell proliferation and invasion, but also induced apoptosis and inhibited migration and angiogenesis in vascular endothelial cells, suggesting that cordycepin may be used as a novel anti-angiogenic therapy in HCC.

Bioactive principles from Cordyceps sinensis: A potent food supplement - A review

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Introducing the importance of Cordyceps sinensis (CS) and its economics.

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Alternative artificial cultivation methods for large scale production to meet the world demand for CS.

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Chemical characterization of compounds in different extracts of CS.

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Potential health benefits and mechanism of action of compounds in CS.

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Possible application of whole fungus or its extracts in food and pharmaceutical industries.

Cordyceps sinensis (CS) is a well-known entamophagus fungus, naturally distributed in the Tibetan Plateau of Asia and Himalayas. Recently this synonym is transferred to Ophiocordyceps by both scientific and non-scientific communities. It is widely used as a tonic and medicinal food in traditional Chinese medicine (TCM), as it possess wonderful health benefits. To support its functional attributes, various investigations have been carried out to find out its adaptogenic, aphrodisiac, anti-oxidant, anti-aging, neuroprotective, nootropic, immunomodulatory, anti-cancer and hepatoprotective role. Its fruiting portion as well as the larvae possesses potent bio-active fractions and their composition almost found to be similar in both. The bioactive principles are nucleosides, exo-polysaccharides, sterols and, proteins, among others. Among nucleosides, adenosine and cordycepin are the major biochemical markers. Further, different types of solvent extracts and their mixtures exhibit wide range of pharmacological activities, while the water and methanol extracts with the richest sources of nucleosides and polysaccharides also show wide range of pharmacological activities. This review gives a panoramic view of potential health benefits of various classes of bio-active fractions along with the need for sustainable management of CS for human wellness.

A real-time qPCR assay to quantify Ophiocordyceps sinensis biomass in Thitarodes larvae

Ophiocordyceps sinensis, an entomogenous fungus parasitic in the larvae of moths (Lepidoptera), is one of the most valuable medicinal fungi, and it only distributed naturally on the Tibetan Plateau. The parasitical amount of O. sinensis in various tissues of the host Thitarodes larvae has an important role in study the occurrence and developmental mechanisms of O. sinensis, but there no an effective method to detect the fungal anamorph. A real-time quantitative PCR (qPCR) system, including a pair of species-specific ITS primers and its related program, was developed for O. sinensis assay with high reliability and efficiency. A calibration curve was established and exhibited a very good linear correlation between the fungal biomass and the C T values (R (2)=0.999419) by the qPCR system. Based on this method, O. sinensis was detected rapidly in four tissues of its host caterpillars, and the results were shown as following: the maximum content of O. sinensis parasitized in the fat-body, and next came body-wall; both of them were much larger than that observed in the haemolymph and intestinal-wall. Taken together, these results show that qPCR assays may become useful tools for study on developmental mechanism of O. sinensis.

Cordycepin Increases Nonrapid Eye Movement Sleep via Adenosine Receptors in Rats

Cordycepin (3′-deoxyadenosine) is a naturally occurring adenosine analogue and one of the bioactive constituents isolated from Cordyceps militaris/Cordyceps sinensis, species of the fungal genus Cordyceps. It has traditionally been a prized Chinese folk medicine for the human well-being. Because of similarity of chemical structure of adenosine, cordycepin has been focused on the diverse effects of the central nervous systems (CNSs), like sleep regulation. Therefore, this study was undertaken to know whether cordycepin increases the natural sleep in rats, and its effect is mediated by adenosine receptors (ARs). Sleep was recorded using electroencephalogram (EEG) for 4 hours after oral administration of cordycepin in rats. Sleep architecture and EEG power spectra were analyzed. Cordycepin reduced sleep-wake cycles and increased nonrapid eye movement (NREM) sleep. Interestingly, cordycepin increased θ (theta) waves power density during NREM sleep. In addition, the protein levels of AR subtypes (A₁, A_2A, and A_2B) were increased after the administration of cordycepin, especially in the rat hypothalamus which plays an important role in sleep regulation. Therefore, we suggest that cordycepin increases theta waves power density during NREM sleep via nonspecific AR in rats. In addition, this experiment can provide basic evidence that cordycepin may be helpful for sleep-disturbed subjects.

Protective roles of Cordyceps on lung fibrosis in cellular and rat models

ETHNOPHARMACOLOGICAL RELEVANCE

Cordyceps sinensis is a fungus used in traditional Chinese medicine as a tonic to soothe the lung for the treatment of fatigue and respiratory diseases. Idiopathic pulmonary fibrosis is a chronic, irreversible and debilitating lung disease showing fibroblast/myofibroblast expansion and excessive deposition of extracellular matrix in the interstitium leading to breathing difficulty. Our previous observation revealed a partial relief of lung fibrosis in patients suffering from severe acute respiratory syndrome (SARS). We hypothesize that Cordyceps has beneficial effects on lung fibrosis and the objective of this study is to explore the target(s) of Cordyceps in the relief of lung fibrosis in animal and cell models and to gain insight into its underlying mechanisms.

MATERIAL AND METHODS

A rat model of bleomycin (BLM)-induced lung fibrosis and a fibrotic cell model with transforming growth factor beta-1 induction were employed in the studies.

RESULTS

Reduction of infiltration of inflammatory cells, deposition of fibroblastic loci and collagen, formation of reactive oxygen species, and production of cytokines, as well as recovery from imbalance of MMP-9/TIMP-1, were observed in fibrotic rats after treatment with Cordyceps in preventive (from the day of BLM administration) and therapeutic (from 14 days after BLM) regimens. In a fibrotic cell model with transforming growth factor beta-1 induction, the human lung epithelial A549 acquired a mesenchymal phenotype and an increase of vimentin expression with a concomitant decrease of E-cadherin. This epithelial-mesenchymal transition could be partially reverted by cordycepin, a major component of Cordyceps.

CONCLUSION

The findings provide an insight into the preventive and therapeutic potentials of Cordyceps for the treatment of lung fibrosis.

Cordycepin inhibits renal interstitial myofibroblast activation probably by inducing hepatocyte growth factor expression

Renal interstitial fibrosis is the common end point of progressive renal diseases leading to the deterioration and eventual loss of renal function. This study investigated the effect and potential mechanism of cordycepin on activation of renal interstitial fibroblast cells. The time and dose-responses of cordycepin in rat renal interstitial fibroblast (NRK-49F) cells were analyzed. The proliferation of NRK-49F and the expression of α-smooth muscle actin (α-SMA) and fibronectin (FN) were examined. The expression and translocation of Smad proteins also were measured by western blot and indirect immunofluorescence staining. The mRNA level of hepatocyte growth factor (HGF) and the expression of HGF receptor c-Met and its phosphorylation (p-Met) were also detected. Cordycepin suppressed the proliferation of NRK-49F and the expression of α-SMA and FN induced by transforming growth factor-β1 (TGF-β1). The pretreatment of cordycepin markedly attenuated the nuclear translocation and accumulation of activated Smad2/3 in NRK-49F cells. Furthermore, cordycepin not only increased HGF expression, but also induced HGF secretion, as well as HGF receptor phosphorylation in NRK-49F cells. Cordycepin possesses renoprotective activity through suppression myofibroblast activation. This action is mediated, at least in part, by blocking nuclear translocation and accumulation of activated Smad2/3 protein and up-regulating anti-fibrotic HGF expression and secretion and HGF receptor activation.