Activation of Early Proinflammatory Responses by TBEV NS1 Varies between the Strains of Various Subtypes

Tick-borne encephalitis (TBE) is an emerging zoonosis that may cause long-term neurological sequelae or even death. Thus, there is a growing interest in understanding the factors of TBE pathogenesis. Viral genetic determinants may greatly affect the severity and consequences of TBE. In this study, nonstructural protein 1 (NS1) of the tick-borne encephalitis virus (TBEV) was tested as such a determinant. NS1s of three strains with similar neuroinvasiveness belonging to the European, Siberian and Far-Eastern subtypes of TBEV were studied. Transfection of mouse cells with plasmids encoding NS1 of the three TBEV subtypes led to different levels of NS1 protein accumulation in and secretion from the cells. NS1s of TBEV were able to trigger cytokine production either in isolated mouse splenocytes or in mice after delivery of NS1 encoding plasmids. The profile and dynamics of TNF-α, IL-6, IL-10 and IFN-γ differed between the strains. These results demonstrated the involvement of TBEV NS1 in triggering an immune response and indicated the diversity of NS1 as one of the genetic factors of TBEV pathogenicity.

Preclinical evaluation of Zanthoxylum piperitum Benn., traditional muscle pain remedy, for joint inflammation

ETHNOPHARMACOLOGICAL RELEVANCE

Zanthoxylum piperitum has been used as a traditional Asian medicine to treat hypertension, stroke, bruise and muscle pain. It has been known to induce detoxification; affect anti-bacterial, anti-oxidant, and tyrosinase activity; inhibit osteosarcoma proliferation; anti-osteoarthritis inflammation. In this study, we aim to identify the therapeutic effect of Z. piperitum 90% EtOH extract (ZPE-LR) on rheumatoid arthritis.

MATERIAL AND METHODS

We investigated the anti-rheumatoid arthritis and -immunomodulatory activities of the ZPE-LR in collagen-induced arthritic (CIA) mice, a rheumatoid arthritis animal model. In order to assess the analgesic effects of ZPE-LR in vivo, acetic acid injection, formaldehyde injection, hot plate model was used. The mechanism for anti-inflammatory activity of ZPE-LR was identified with LPS-stimulated Raw 264.7 cells.

RESULTS

Pharmacologically, oral administration of ZPE-LR into CIA mice resulted in a significant and dose-dependent decrease in clinical arthritis score and paw swelling compared to untreated negative control. Pathologic examination showed that ZPE-LR prevented morphological change in cartilage and destruction of phalanges in CIA mice. This protective effect was associated with reduced pain, inflammatory mediators such as NO, TNF-α, IL-1β, and IL-6, as well as COX-2 and iNOS expression. Furthermore, reduction of phosphor-ERK and BDNF indicates a novel rheumatoid arthritis-regulating mechanism by ZPE-LR treatment.

CONCLUSIONS

These data suggest that the administration of ZPE-LR remarkably inhibited CIA progression and might be helpful in suppressing inflammation and pain in rheumatoid arthritis.