Antiviral Activity of Gemcitabine Against Echovirus 30 Infection in Vitro

Echovirus 30 is one of the major causes of meningitis in children and adults. The purpose of our current study was to investigate whether selected antiviral drugs could provide antiviral activity against echovirus 30. Using RD cells, we assessed the cytopathic effect of echovirus 30, including viral RNA levels as indicators of viral replication. The effects of gemcitabine were compared to rupintrivir, a well-known antiviral drug. To understand the activity gemcitabine exerts on the viral life cycle, time course and time-of-addition assays were implemented. The most effective compounds against echovirus 30 were gemcitabine and rupintrivir, as demonstrated by their concentration-dependent activity. Gemcitabine affects the early stages of echovirus 30 infection by disrupting viral replication. However, gemcitabine failed to directly inactivate echovirus 30 particles or impede viral uptake into the RD cells. Gemcitabine can be considered as a lead candidate in the development of echovirus 30 antiviral drugs, specifically in the early stages of echovirus 30 replication.

Chemical Constituents of Essential Oils Possessing Anti-Influenza A/WS/33 Virus Activity

OBJECTIVES: This study was conducted to determine whether essential oils had anti-influenza A/WS/33 virus activity and whether there were specific compounds associated with this activity. METHODS: There were 63 essential oils evaluated for anti-influenza (A/WS/33 virus) activity using a cytopathic effect reduction method. The chemical composition of the anti-influenza essential oils was phytochemically analyzed by gas chromatography-mass spectrometry. RESULTS: The antiviral assays demonstrated that 11 of the 62 essential oils (100 μg/mL) possessed anti-influenza activity, reducing visible cytopathic effects of influenza A/WS/33 virus activity by > 30%. Furthermore, marjoram, clary sage and anise oils exhibited anti-influenza A/WS/33 virus activity of > 52.8%. However, oseltamivir (the anti-influenza A and B drug), showed cytotoxicity at the same concentration (100 μg/mL) as the essential oils. The chemical composition detected by GC–MS analysis, differed amongst the 3 most potent anti-viral essential oils (marjoram, clary sage and anise oils) except for linalool, which was detected in all 3 essential oils. CONCLUSION: This study demonstrated anti-influenza activity in 11 essential oils tested, with marjoram, clary sage and anise essential oils being the most effective at reducing visible cytopathic effects of the A/WS/33 virus. All 3 oils contained linalool, suggesting that this may have anti-influenza activity. Further investigation is needed to characterize the antiviral activity of linalool against influenza A/WS/33 virus.

Antiviral Activity of Itraconazole against Echovirus 30 Infection In Vitro

OBJECTIVES: Echovirus 30 is a major cause of meningitis in children and adults. The aim of this study was to investigate whether the antifungal drug itraconazole could exhibit antiviral activity against echovirus 30. METHODS: The cytopathic effect and viral RNA levels were assessed in RD cells as indicators of viral replication. The effects of itraconazole were compared to those of two known antiviral drugs, rupintrivir and pleconaril. The time course and time-of-addition assays were used to approximate the time at which itraconazole exerts its activity in the viral cycle. RESULTS: Itraconazole and rupintrivir demonstrated the greatest potency against echovirus 30, demonstrating concentration-dependent activity, whereas pleconaril showed no antiviral activity. Itraconazole did not directly inactivate echovirus 30 particles or impede viral uptake into RD cells, but did affect the initial stages of echovirus 30 infection through interference with viral replication. CONCLUSION: Itraconazole can be considered a lead candidate for the development of antiviral drugs against echovirus 30 that may be used during the early stages of echovirus 30 replication.

In Vitro Antiviral Activity of Sakuranetin against Human Rhinovirus 3

OBJECTIVES: Rhinoviruses (RVs) cause common cold and are associated with exacerbation of chronic inflammatory respiratory diseases. Until now, no clinically effective antiviral chemotherapeutic agents to treat diseases caused by human rhinoviruses (HRVs) have been reported. We assessed the anti-HRV3 activity of sakuranetin isolated from Sorbus commixta Hedl. in human epithelioid carcinoma cervix (HeLa) cells, to evaluate its anti-rhinoviral potential in the clinical setting. METHODS: Antiviral activity and cytotoxicity as well as the effect of sakuranetin on HRV3-induced cytopathic effects (CPEs) were evaluated using the sulforhodamine B (SRB) method using CPE reduction. The morphology of HRV3-infected cells was studied using a light microscope. RESULTS: Sakuranetin actively inhibited HRV3 replication and exhibited antiviral activity of more than 67% without cytotoxicity in HeLa cells, at 100 μg/mL. Ribavirin showed anti-HRV3 activity similar to that of sakuranetin. Treatment of HRV-infected HeLa cells with sakuranetin visibly reduced CPEs. CONCLUSION: The inhibition of HRV production by sakuranetin is mainly due to its general antioxidant activity through inhibition of viral adsorption. Therefore, the antiviral activity of sakuranetin should be further investigated to elucidate its mode of action and prevent HRV3-mediated diseases in pathological conditions.

Antiviral Activity of Corylus heterophylla Fisch Against Porcine Epidemic Diarrhea Virus Infection

The porcine epidemic diarrhea virus (PEDV) has recently been shown to cause huge economic losses in the global pork industry. Our results demonstrated that the extract dose-dependently inhibited the replication of PEDV and reduced the visible cytopathic effect (CPE). Treatment with C. heterophylla Fisch extract resulted in marked reduction of PEDVinduced cytokine and chemokine expression. The antiviral activity of C. heterophylla Fisch extract on PEDV replication was found to be primarily exerted at the early stages after infection. Taken together, our data indicate that C. heterophylla Fisch extract may be a good therapeutic agent for use against PEDV and also a potential candidate to be evaluated against other human and animal coronaviruses.

Inhibitory Effects of Norwogonin, Oroxylin A, and Mosloflavone on Enterovirus 71

Severe complications associated with EV71 infections are a common cause of neonatal death. Lack of effective therapeutic agents for these infections underlines the importance of research for the development of new antiviral compounds. In the present study, the anti-EV71 activity of norwogonin, oroxylin A, and mosloflavone from Scutellaria baicalensis Georgi was evaluated using a cytopathic effect (CPE) reduction method, which demonstrated that all three compounds possessed strong anti-EV71 activity and decreased the formation of visible CPEs. Norwogonin, oroxylin A, and mosloflavone also inhibited virus replication during the initial stage of virus infection, and they inhibited viral VP2 protein expression, thereby inhibiting viral capsid protein synthesis. However, ribavirin has a relatively weaker efficacy compared to the other drugs. Therefore, these findings provide important information that will aid in the utilization of norwogonin, oroxylin A, and mosloflavone for EV71 treatment.

Neuraminidase Inhibitors from the Fermentation Broth of Phellinus linteus

During a search for neuraminidase inhibitors derived from medicinal fungi, we found that the fermentation broth of Phellinus linteus exhibited potent neuraminidase inhibitory activity. Through bioassay-guided fractionation, two active compounds were purified from the ethyl acetate-soluble portion of the fermentation broth of P. linteus. These structures were identified as inotilone (1) and 4-(3,4-dihydroxyphenyl)-3-buten-2-one (2) by spectroscopic methods. Compounds 1 and 2 inhibited H1N1 neuraminidase activity with IC50 values of 29.1 and 125.6 microM, respectively, in a dose-dependent manner. They also exhibited an antiviral effect in a viral cytopathic effect reduction assay using MDCK cells. These results suggest that compounds 1 and 2 from the culture broth of P. linteus would be good candidates for the prevention and therapeutic strategies towards viral infections.

Protective Effect of HP08-0106 on Ligature-induced Periodontitis in Rats

Periodontitis is an inflammatory disorder of the periodontium, characterized by destruction of the tooth supporting tissues including alveolar bone and mediated by various pro-inflammatory mediators. Here, we demonstrated that HP08-0106, composed of four crude drugs-Gardenia jasminoides Grandiflora, Angelica gigas Nakai, Rehmannia glutinosa, and Schizonepeta tenuifolia in a weight ratio of 2:2:1:2, perturbs inflammatory responses, osteoclast formation in LPS-induced RAW 264.7 cells and alveolar bone resorption in ligature-induced periodontitis. HP08-0106 decreased the protein level of iNOS and COX2 as well as the secreted level of IL-1beta, indicating that HP08-0106 has antiinflammatory effects. HP08-0106 also inhibited the expression of genes associated with osteoclastogenesis including c-Fos, MMP-9 and TRAP. Moreover, HP08-0106 exhibited a protective effect from alveolar bone loss in ligature-induced periodontitis animal models. Our results strongly suggest that HP08-0106 represent an important therapeutic tool to treat inflammatory disorders associated with bone loss such as periodontitis.

Hexane-Soluble Fraction of the Common Fig, Ficus carica, Inhibits Osteoclast Differentiation in Murine Bone Marrow-Derived Macrophages and RAW 264.7 Cells

Osteoclasts, derived from multipotent myeloid progenitor cells, play homeostatic roles in skeletal modeling and remodeling, but may also destroy bone in pathological conditions such as osteoporosis and rheumatoid arthritis. Osteoclast development depends critically on a differentiation factor, the receptor activator of NF-kappaB ligand (RANKL). In this study, we found that the hexane soluble fraction of the common fig Ficus carica (HF6-FC) is a potent inhibitor of osteoclastogenesis in RANKL-stimulated RAW264.7 cells and in bone marrow-derived macrophages (BMMs). HF6-FC exerts its inhibitory effects by suppression of p38 and NF-kappaB but activation of ERK. In addition, HF6-FC significantly decreased the expression of NFATc1 and c-Fos, the master regulator of osteoclast differentiation. The data indicate that components of HF6-FC may have therapeutic effects on bone-destructive processes such as osteoporosis, rheumatoid arthritis, and periodontal bone resorption.

Effect of Hypoxia on Cytokine Production in Rheumatoid Fibroblast-Like Synoviocytes / 대한류마티스학회지

OBJECTIVE: Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by increased production of cytokines, proliferation of fibroblast-like synoviocytes (FLS) and joint destruction. It is well known that the involved joints in RA are hypoxic. Hypoxia may play a role in the pathogenesis of RA. We thought that hypoxia might alter the production of cytokines by FLS and these changes could affect the biologic behaviors of FLS. Based on that, we investigated whether hypoxia affects the production of cytokines in FLS and the effect of these changes on matrix metalloproteinases (MMPs) expression. METHODS: Fibroblast-like synoviocytes from human rheumatoid synovial tissue obtained duringjoint replacement surgery were cultured in vitro. Hypoxic culture was performed by incubating cells in BBL? Gaspak pouchTM anaerobic system. After incubation under hypoxic condition for 24 hr, the concentrations of various cytokines in culture supernatants were determined by ELISA. To determine the effect of highly expressed cytokines on MMP expression, we performed ELISA of MMP-1, MMP-2 and MMP-3 in cultured FLS, after stimulation with respective cytokines. RESULTS: In hypoxic state, IL-6, IL-8 and vascular endothelial growth factor (VEGF) concentrations were significantly increased compared to those in normoxic condition. However, there were little differences in IL-1, IL-2, IL-4, TNF-alpha and TGF-beta. Stimulation of FLS with IL-6 and IL-8 showed the increased concentrations of MMP-1, MMP-2 and MMP-3. CONCLUSION: Hypoxic environment of rheumatoid synovium might affect FLS to produce proinflammatory and proangiogenic cytokine such as IL-6 and IL-8. These cytokines again could stimulate MMPs production in FLS leading to joint destruction.

Regulation of Matrix Metalloproteinases and Tissue Inhibitor of Metalloproteinase-1 Expression by Hypoxia in Rheumatoid and Osteoarthritis Fibroblast-Like Synoviocytes / 대한류마티스학회지

OBJECTIVE: The rheumatoid synovium is a hypoxic environment and hypoxia has been implicated to have a role in the pathogenesis of rheumatoid arthritis (RA). In this work, we tried to investigate the effect of hypoxia on the expression of matrix metalloproteinase (MMP)-1, -3 and tissue inhibitor of metalloproteinase (TIMP)-1 in rheumatoid and osteoarthritis (OA) fibroblast-like synoviocytes (FLS). METHODS: FLS obtained from RA and OA patients were cultured under normoxic or hypoxic condition for 48 hours. Western blot analyses for MMP-1, -3 and TIMP-1 were performed. TIMP-1 mRNA levels were measured by Northern blot analysis. RESULTS: Hypoxia increased MMP-1 expression in rheumatoid FLS compared with normoxia. TIMP-1 expression was decreased by hypoxia in rheumatoid FLS in both protein and mRNA levels. On the other hand, hypoxia did not significantly affect MMP-1, -3 and TIMP-1 expressions in OA FLS. CONCLUSION: These results suggest that microenvironment such as hypoxia may directly contribute to joint destruction in RA by increasing the ratio of MMP-1 to TIMP-1 production in FLS.

Expression of Oncoprotein in Rheumatoid Synovium / 대한류마티스학회지

OBJECTIVE: The synovium in rheumatoid arthritis(RA) is characterized by an increase in the thickness of lining layer and infiltration of cells into the sublining area. Histomorphologic studies of RA have indicated that initial destruction is more closely related to the presence of transformed appearing proliferating synovial cells than to the presence of subsynovial or periarticular inflammation. Based on the fact that synovial lining cells have some properties of transformed appearing cells, we examined the expressions of Fos, Jun and Myc oncoproteins in the synovial tissue from patients with rheumatoid arthritis and osteoarthritis. METHODS: Synovial tissues from 15 patients with RA and 15 with osteoarthritis(OA) were studied by the immunohistochemical staining technique. Nine of 15 RA specimen were from arthroscopic synovectomy and the other 6 were from total knee replacement arthroplasty. RESULT: In all specimen studied, Myc and Fos were expressed in the synovial lining cells and Myc, Fos and Jun were expressed in the sublining cells, including lymphocytes, other inflammatory cells and blood vessels. Lymphocytes in the diffuse infiltrates showed increased expression of three oncoproteins compared to lymphocytes in the nodular aggregates. When oncoprotein expressions in RA were compared to OA, Fos and Myc expressions in the synovial lining cell layer were significantly higher in RA than in OA and Jun, Fos and Myc expressions in inflammatory cells were significantly higher in RA than in OA. The expressions of Fos and Myc were significantly correlated with the degree of synovial hypercellularity. In RA, the expressions of all three oncoproteins were increased in synovectomy group than joint replacement group. CONCLUSION: We observe that there are increased expressions of Myc, Fos and Jun in RA synovium than OA. These changes are more prominent in synovectomy group than joint replacement group, which suggest the differential expression of oncoproteins according to disease progression.