Inhibition of the replication of a hepatitis C virus-like RNA template by interferon and 3'-deoxycytidine

Effect of Cordyceps militaris Hot Water Extract on Immunomodulation-associated Gene Expression in Broilers, Gallus gallus

Cordyceps militaris is a well-known Chinese medicinal fungus that has been used as a nutraceutical food in several Asian countries. Cordycepin (3′-deoxyadenosine), a secondary metabolite produced from Cordyceps militaris, has been demonstrated to exert a wide spectrum of pharmacological activities, such as anti-microbial and antitumor activities. However, the effect of cordycepin on immunomodulation in broilers is poorly investigated. In the current study, we investigated the effect of cordycepin (9.69, 19.38, and 38.76 mg) from Cordyceps militaris hot water extract (CMHW) on growth performance and immunocompetence in broilers. Results showed that CMHW significantly decreased inducible nitric oxide synthase (iNOS) mRNA levels in the bursa of Fabricius after 4 weeks of feeding (P<0.05). CMHW treatment reduced cyclooxygenase-2 (COX-2) mRNA levels in the spleen and bursa of Fabricius after 4 weeks of feeding (P<0.05). Supplementation of CMHW for 3 days after vaccination reduced iNOS mRNA level in the spleen of 14 and 28 day-old broilers (P<0.05). Prior to vaccination, CMHW pretreatment significantly down-regulated COX-2 mRNA levels in the spleen and bursa of Fabricius of 14-day-old broilers (P<0.05). Furthermore, CMHW significantly reduced lipopolysaccharide (LPS)-induced iNOS and COX-2 mRNA levels in the spleen and bursa of Fabricius (P<0.05). CMHW treatment attenuated LPS-induced IFN-γ expression in the spleen and bursa of Fabricius, whereas CMHW induced IL-4 expression in these organs in response to LPS challenge (P<0.05). Taken together, these observations demonstrate that CMHW exerts an immunomodulatory role in broilers. CMHW is a potential novel feed additive with applications in inflammation-related diseases and bacterial infection in broilers.

Effects of Cordyceps militaris spent mushroom substrate on mucosal and serum immune parameters, disease resistance and growth performance of Nile tilapia, (Oreochromis niloticus)

The aim of present study was determination effects of dietary administration of C. militaris spent mushroom substrate (SMS) on mucosal and serum immune parameters, disease resistance, and growth performance of Nile tilapia (Oreochromis niloticus). Two hundred twenty five fish of similar weight (37.28 ± 0.10 g) were assigned to the following diets [0 (T1- Control), 5 (T2), 10 (T3), 20 (T4) and 40 g kg^-1 (T5) SMS]. After 60 days of feeding trial, growth performance, skin mucus lysozyme and peroxidase activities as well as serum innate immune were measured. In addition, survival rate and innate immune responses were calculated after challenge test (15 days) against Streptococcus agalactiae. The results revealed that regardless of inclusion levels, feeding Nile tilapia with SMS supplemented diets significantly increased skin mucus lysozyme and peroxidase activities as well as serum immune parameters (SL, ACH50, PI, RB, and RB) compared control group (P < 0.05). The highest increment of immune parameters was observed in fish fed 10 g kg^-1 SMS which was significantly higher than other treatments (P < 0.05). Also, the relative percent survival (RSP) in T2, T3, T4, and T5 was 61.11%, 88.89%, 66.67, and 55.56%, respectively. Among the supplemented groups, fish fed 10 g kg^-1 SMS showed significant higher RPS and resistance to S. agalactiae than other groups (P < 0.05). Regarding the growth performance, SGR, WG, FW, and FCR were remarkably improved (P < 0.05) in SMS groups; the highest improvement observed in 10 g kg^-1 SMS treatment. According to these finding, administration of 10 g kg^-1 SMS is suggested in tilapia to improve growth performance and health status.

Separation of cordycepin from Cordyceps militaris fermentation supernatant using preparative HPLC and evaluation of its antibacterial activity as an NAD+-dependent DNA ligase inhibitor

Cordycepin exhibits various bio-activities, including anticancer, antibacterial, antiviral and immune regulation activities, and is a significant focus of research. However, the preparation of high-purity cordycepin remains challenging. Also, the molecular target with which cordycepin interacts to cause an antibacterial effect remains unknown. In the present study, cordycepin was prepared by preparative high-performance liquid chromatography (prep-HPLC) and the purity obtained was 99.6%, indicating that this technique may be useful for the large-scale isolation of cordycepin in the future. The results of computational molecular docking analysis indicated that the interaction energy between cordycepin and NAD+-dependent DNA ligase (LigA) was lower than that between cordycepin and other common antibacterial targets. The highly pure cordycepin obtained by prep-HPLC demonstrated inhibitory activity against LigA from various bacteria in vitro. In conclusion, cordycepin may be useful as a broad-spectrum antibiotic targeting LigA in various bacteria.

Column chromatographic extraction and preparation of cordycepin from Cordyceps militaris waster medium

Large amounts of solid medium containing cordycepin, used in the industrial production of Cordyceps militaris through solid fermentation, are discarded as waste and contaminate the environment. We have developed a new column chromatographic extraction (CCE) method for the extraction of cordycepin from this waste and a preparation method for further separation and purification. Dried waste material was imbibed in four times its volume of water for 6 h, transferred to columns and eluted with water. Eluates were directly separated with macroporous resin DM130 columns followed by purification steps, including precipitation, crystallization, and polyamide column chromatography. Extraction rates of more than 97% were obtained with 12 volumes of water for a single column and 4 volumes of water for eluates circulated through 3 different columns designed to concentrate cordycepin. Cordycepin (98% pure) was obtained following the separation and purification processes, with an overall recovery rate of more than 90%. The CCE method has high extraction efficiency, uses a minimum volume of solvent and can be used for both quantitative analysis and large preparations of cordycepin from waste. The preparation method is simple, highly efficient, energy-saving, environmentally friendly, and has been demonstrated to be effective for large preparations of cordycepin from waste with low equipment and operating costs.

A cell-based model of HCV-negative-strand RNA replication utilizing a chimeric hepatitis C virus/reporter RNA template

The inability of hepatitis C virus (HCV) to replicate in cell culture has hindered the discovery of antiviral agents against this virus. One of the biggest challenges has been to find a model that allows one to easily and accurately quantify the level of HCV RNA replication that is occurring inside the cell. In an attempt to solve this problem, we have created a plasmid pMJ050 that encodes a chimeric 'HCV-like' RNA that can act as a reporter for HCV RNA replication. This RNA consists of an antisense copy of the firefly luciferase sequence flanked by the 5' and 3' untranslated regions of the negative strand of the HCV RNA. If, in cells that contain functional HCV proteins, the chimeric RNA is recognized as a substrate for the viral RNA-dependent RNA polymerase, the chimeric RNA will be transcribed into the complementary strand. This RNA has a 5' HCV internal ribosome entry site and the luciferase sequence in the coding orientation, allowing translation of the RNA into biologically active luciferase. When pMJ050 was transfected into a cell line that is stably transfected with a cDNA copy of the HCV 1b genome, luciferase was produced in a manner that was dependent upon the presence of at least a functional HCV RNA-dependent RNA polymerase. In addition, we constructed a cell line, 293B4alpha that constitutively produced luciferase in response to the presence of functional HCV proteins. This system permits the accurate determination of the level of HCV RNA replication by the quantification of luciferase.