Therapeutic targets and biological mechanisms of action of curcumin against Zika virus: In silico and in vitro analyses.

Zika virus (ZIKV) is a mosquito-borne flavivirus, that could cause congenital Zika syndrome (CZS), characterized by microcephaly, neurological complications and fetal deaths. No specific treatments for ZIKV are currently available, highlighting the urgent global need to identify and develop therapeutic agents. Drug repositioning of approved natural compounds can provide effective alternative solutions for novel antiviral development. The current study focused on curcumin, a component of turmeric known to exert diverse antiviral effects. We integrated in silico information from publicly available databases to predict interactions between curcumin and potential targets of ZIKV. In our network analysis, we identified four targets, TP53, AKT1, PTEN, and TNF, which were identified as potential targets associated with ZIKV. Based on retrieved targets, we performed molecular docking study and identified curcumin-TNF showed the strongest binding among four targets. The anti-Zika effects of curcumin were validated in vitro with the aid of antiviral and plaque reduction assay. Curcumin at concentrations ranging from 12.5 to 50 µM displayed significant antiviral activity in a dose-dependent manner (p < 0.05). In view of its natural abundance and prevalence in the human diet, curcumin holds significant promise for treatment of ZIKV infections.

Pine Needle Extract Applicable to Topical Treatment for the Prevention of Human Papillomavirus Infection.

Most cervical cancers are associated with high-risk human papillomavirus (HPV) infection. Currently, cervical cancer treatment entails surgical removal of the lesion, but treatment of infection and preventing tissue damage are issues that still remain to be addressed. Herbal medicine and biological studies have focused on developing antiviral drugs from natural sources. In this study, we analyzed the potential antiviral effects of Pinus densiflora Sieb. et Zucc. leaf extracts against HPV. The pine needle extracts from each organic solvent were analyzed for antiviral activity. The methylene chloride fraction (PN-MC) showed the highest activity against HPV pseudovirus (PV). The PN-MC extract was more effective before, rather than after treatment, and therefore represents a prophylactic intervention. Mice were pre-treated with PN-MC via genital application or oral administration, followed by a genital or subcutaneous challenge with HPV PV, respectively. The HPV challenge results showed that mice treated via genital application exhibited complete protection against HPV. In conclusion, PN-MC represents a potential topical virucide for HPV infection.

A network-based pharmacology study of active compounds and targets of Fritillaria thunbergii against influenza.

Seasonal and pandemic influenza infections are serious threats to public health and the global economy. Since antigenic drift reduces the effectiveness of conventional therapies against the virus, herbal medicine has been proposed as an alternative. Fritillaria thunbergii (FT) have been traditionally used to treat airway inflammatory diseases such as coughs, bronchitis, pneumonia, and fever-based illnesses. Herein, we used a network pharmacology-based strategy to predict potential compounds from Fritillaria thunbergii (FT), target genes, and cellular pathways to better combat influenza and influenza-associated diseases. We identified five compounds, and 47 target genes using a compound-target network (C-T). Two compounds (beta-sitosterol and pelargonidin) and nine target genes (BCL2, CASP3, HSP90AA1, ICAM1, JUN, NOS2, PPARG, PTGS1, PTGS2) were identified using a compound-influenza disease target network (C-D). Protein-protein interaction (PPI) network was constructed and we identified eight proteins from nine target genes formed a network. The compound-disease-pathway network (C-D-P) revealed three classes of pathways linked to influenza: cancer, viral diseases, and inflammation. Taken together, our systems biology data from C-T, C-D, PPI and C-D-P networks predicted potent compounds from FT and new therapeutic targets and pathways involved in influenza.

Identifying Active Compounds and Targets of Fritillariae thunbergii against Influenza-Associated Inflammation by Network Pharmacology Analysis and Molecular Docking.

Complications due to influenza are often associated with inflammation with excessive release of cytokines. The bulbs of Fritillariae thunbergii (FT) have been traditionally used to control airway inflammatory diseases, such as bronchitis and pneumonia. To elucidate active compounds, the targets, and underlying mechanisms of FT for the treatment of influenza-induced inflammation, systems biology was employed. Active compounds of FT were identified through the TCMSP database according to oral bioavailability (OB) and drug-likeness (DL) criteria. Other pharmacokinetic parameters, Caco-2 permeability (Caco-2), and drug half-life (HL) were also identified. Biological targets of FT were retrieved from DrugBank and STITCH databases, and target genes associated with influenza, lung, and spleen inflammation were collected from DisGeNET and NCBI databases. Compound-disease-target (C-D-T) networks were constructed and merged using Cytoscape. Target genes retrieved from the C-D-T network were further analyzed with GO enrichment and KEGG pathway analysis. In our network, GO and KEGG results yielded two compounds (beta-sitosterol (BS) and pelargonidin (PG)), targets (PTGS1 (COX-1) and PTGS2 (COX-2)), and pathways (nitric oxide, TNF) were involved in the inhibitory effects of FT on influenza-associated inflammation. We retrieved the binding affinity of each ligand-target, and found that PG and COX-1 showed the strongest binding affinity among four binding results using a molecular docking method. We identified the potential compounds and targets of FT against influenza and suggest that FT is an immunomodulatory therapy for influenza-associated inflammation.

Antiviral Activity of Fritillaria thunbergii Extract against Human Influenza Virus H1N1 (PR8) In Vitro, In Ovo and In Vivo.

Influenza viruses cause respiratory diseases in humans and animals with high morbidity and mortality rates. Conventional anti-influenza drugs are reported to exert side effects and newly emerging viral strains tend to develop resistance to these commonly used agents. Fritillaria thunbergii (FT) is traditionally used as an expectorant for controlling airway inflammatory disorders. Here, we evaluated the therapeutic effects of FT extracts against influenza virus type A (H1N1) infection in vitro, in ovo, and in vivo. In the post-treatment assay, FT extracts showed high CC50 (7,500 µg/ml), indicating low toxicity, and exerted moderate antiviral effects compared to oseltamivir (SI 50.6 vs. 222) in vitro. Antiviral activity tests in ovo revealed strong inhibitory effects of both FT extract and oseltamivir against H1N1 replication in embryonated eggs. Notably, at a treatment concentration of 150 mg/kg, only half the group administered oseltamivir survived whereas the FT group showed 100% survival, clearly demonstrating the low toxicity of FT extracts. Consistent with these findings, FT-administered mice showed a higher survival rate with lower body weight reduction relative to the oseltamivir group upon treatment 24 h after viral infection. Our collective results suggest that FT extracts exert antiviral effects against influenza H1N1 virus without inducing toxicity in vitro, in ovo or in vivo, thereby supporting the potential utility of FT extract as a novel candidate therapeutic drug or supplement against influenza.

Antiviral activity of Poncirus trifoliata seed extract against oseltamivir-resistant influenza virus.

The emergence of oseltamivir-resistant variants of influenza virus has highlighted the necessity for the development of more effective novel antiviral drugs. To date, numerous researchers have focused on developing antiviral drugs using natural resources, such as traditional herbal medicines. Poncirus trifoliata is widely used in oriental medicine as a remedy for gastritis, dysentery, inflammation and digestive ulcers. In this study, we investigated the potential antiviral effect of the Poncirus trifoliata orange seed extract against influenza virus. An ethanol extract of Poncirus trifoliata seeds (PTex) inhibited the activity of influenza viruses, in particular, oseltamivir- resistant strains, in Madin-Darby canine kidney cells. In contrast to oseltamivir, PTex exerted a significant inhibitory effect on the cellular penetration pathway of the virus rather than HA receptor binding. The potent antiviral effect and novel working mechanism of PTex support its further development as an effective natural antiviral drug with a wide spectrum of activity against influenza and oseltamivir-resistant viruses.

Image-guided synergistic photothermal therapy using photoresponsive imaging agent-loaded graphene-based nanosheets.

We report the image-guided synergistic photothermal antitumor effects of photoresponsive near-infrared (NIR) imaging agent, indocyanine green (ICG), by loading onto hyaluronic acid-anchored, reduced graphene oxide (HArGO) nanosheets. Loading of ICG onto either rGO (ICG/rGO) or HArGO (ICG/HArGO) substantially improved the photostability of photoresponsive ICG upon NIR irradiation. After 1min of irradiation, the NIR absorption peak of ICG almost disappeared whereas the peak of ICG on rGO or HArGO was retained even after 5min of irradiation. Compared with plain rGO, HArGO provided greater cellular delivery of ICG and photothermal tumor cell-killing effects upon laser irradiation in CD44-positive KB cells. The temperature of cell suspensions treated with ICG/HArGO was 2.4-fold higher than that of cells treated with free ICG. Molecular imaging revealed that intravenously administered ICG/HArGO accumulated in KB tumor tissues higher than ICG/rGO or free ICG. Local temperatures in tumor tissues of laser-irradiated KB cell-bearing nude mice were highest in those intravenously administered ICG/HArGO, and were sufficient to trigger thermal-induced complete tumor ablation. Immunohistologically stained tumors also showed the highest percentages of apoptotic cells in the group treated with ICG/HArGO. These results suggest that photoresponsive ICG-loaded HArGO nanosheets could serve as a potential theranostic nano-platform for image-guided and synergistic photothermal antitumor therapy.

Topical application of porcine placenta extract inhibits the progression of experimental contact hypersensitivity.

AIM OF STUDY: Placenta extract features as a composition of ointments used for skin beautification, dermatological diseases and skin dryness. However, little evidence has been cited about its underlying mechanisms of action by which it exerts a beneficial role in dermatological diseases in vivo. In this study, we intended to test the effect of topical application of porcine placenta extract in mouse model of contact hypersensitivity and elucidate its mechanism of action. MATERIALS AND METHODS: To test the in vitro effect of porcine placenta extract, RAW 264.7 cells were cocultured with porcine placenta extract and stimulated with LPS (1 µg/ml) and the expression of inflammatory mediator TNF-α was estimated by RT-PCR at the mRNA level and by intracellular staining at the protein level. To further test in vivo efficacy, porcine placenta extract was topically applied to the mice with experimental skin hypersensitivity. For in vivo studies placenta extract in gel form was topically applied to ear of DNCB-induced contact hypersensitivity mouse model everyday for 2 weeks and progression of the disease was estimated by following criteria: (a) ear thickness, (b) serum IgE level by ELISA, (c) histological examination of ear tissue by H&E staining and (d) cytokine profile of total cells and CD4(+) T cells by real time PCR. RESULTS: Topical application of porcine placenta extract on mouse ears with contact hypersensitivity decreased the severity and progression of the disease manifested by reducing ear swelling, inflammation and edema. Histological evaluation showed that placenta extract treatment reduced lymphocyte infiltration in the ear tissues. Protective effect of placenta extract is also associated with down-regulation of serum IgE level and inflammatory cytokine production (IL-1ß, IFN-γ, TNF-α, IL-4, IL-12 and IL-17) in total lymph node cells and CD4(+) T cells. CONCLUSIONS: Our data indicate that protective effect of porcine placenta extract in contact hypersensitivity is mediated by inhibition of the inflammatory responses and IgE production, suggesting a potential therapeutic application of porcine placenta extract to modulate skin inflammation.

Enhanced humoral and cellular immune responses after sublingual immunization against human papillomavirus 16 L1 protein with adjuvants.

Needle-free nonparenteral vaccines offer a number of practical advantages, especially in developing countries. To address the effects of vaccine administration route, we tested mucosal and systemic immune responses against human papillomavirus 16 L1(HPV16L1) protein using intranasal, intravaginal, transdermal, sublingual (SL) and intramuscular routes. The SL route provided the most effective mucosal secretory IgA (sIgA) and serum IgG responses. After a 150 microg antigen dose via the SL route, saliva sIgA levels were 7.2- and 5.8-fold higher than those achieved via intravaginal and transdermal routes, respectively. Notably, SL administration even produced 4.6-fold higher levels of vaginal sIgA levels than did intravaginal delivery of 150 microg antigen. To enhance the immunogenicity of SL vaccines, we tested the adjuvanticity of nine molecules: three toll-like receptor agonists, three nucleotide-binding oligomerization-domain agonists, vitamin D3, poly-gamma-glutamic acid and cholera toxin subunit B (CTB). Among the molecules tested, CTB provided the most enhanced mucosal sIgA and systemic IgG induction. SL-applied CTB enhanced the production of interleukin-4 and interferon-gamma from stimulated CD4+ T cells. Moreover, interferon-gamma-producing CD8+ T cell responses were increased 1.7-fold after co-treatment with SL CTB and HPV16L1. These results suggest the potential of the SL route for delivery of HPV16L1 vaccines using CTB as an adjuvant.