The small molecule AZD6244 inhibits dengue virus replication in vitro and protects against lethal challenge in a mouse model.

Dengue virus (DENV) is the most common mosquito-borne viral disease. The World Health Organization estimates that 400 million new cases of dengue fever occur every year. Approximately 500,000 individuals develop severe and life-threatening complications from dengue fever, such as dengue shock syndrome (DSS) and dengue hemorrhagic fever (DHF), which cause 22,000 deaths yearly. Currently, there are no specific licensed therapeutics to treat DENV illness. We have previously shown that the MEK/ERK inhibitor U0126 inhibits the replication of the flavivirus yellow fever virus. In this study, we demonstrate that the MEK/ERK inhibitor AZD6244 has potent antiviral efficacy in vitro against DENV-2, DENV-3, and Saint Louis encephalitis virus (SLEV). We also show that it is able to protect AG129 mice from a lethal challenge with DENV-2 (D2S20). The molecule is currently undergoing phase III clinical trials for the treatment of non-small-cell lung cancer. The effect of AZD6244 on the DENV life cycle was attributed to a blockade of morphogenesis. Treatment of AG129 mice twice daily with oral doses of AZD6244 (100 mg/kg/day) prevented the animals from contracting dengue hemorrhagic fever (DHF)-like lethal disease upon intravenous infection with 1 × 105 PFU of D2S20. The effectiveness of AZD6244 was observed even when the treatment of infected animals was initiated 1-2 days postinfection. This was also followed by a reduction in viral copy number in both the serum and the spleen. There was also an increase in IL-1ß and TNF-α levels in mice that were infected with D2S20 and treated with AZD6244 in comparison to infected mice that were treated with the vehicle only. These data demonstrate the potential of AZD6244 as a new therapeutic agent to treat DENV infection and possibly other flavivirus diseases.

Neurological manifestations of Chikungunya and Zika infections.

The epidemics of Chikungunya virus (CHIKV) and Zika virus (ZIKV) infections have been considered the most important epidemiological occurrences in the Americas. The clinical picture of CHIKV infection is characterized by high fever, exanthema, myalgia, headaches, and arthralgia. Besides the typical clinical picture of CHIKV, atypical manifestations of neurological complications have been reported: meningo-encephalitis, meningoencephalo-myeloradiculitis, myeloradiculitis, myelitis, myeloneuropathy, Guillain-Barré syndrome and others. The diagnosis is based on clinical, epidemiological, and laboratory criteria. The most common symptoms of ZIKV infection are skin rash (mostly maculopapular), fever, arthralgia, myalgia, headache, and conjunctivitis. Some epidemics that have recently occurred in French Polynesia and Brazil, reported the most severe conditions, with involvement of the nervous system (Guillain-Barré syndrome, transverse myelitis, microcephaly and meningitis). The treatment for ZIKV and CHIKV infections are symptomatic and the management for neurological complications depends on the type of affliction. Intravenous immunoglobulin, plasmapheresis, and corticosteroid pulse therapy are options.

Neurological manifestations of Chikungunya and Zika infections

As epidemias provocadas pelo vírus Chikungunya (CHIK) e Zika vírus (ZIKV) têm sido consideradas as ocorrências epidemiológicas mais importantes da América. O quadro clínico da infecção por CHIK caracteriza-se por febre alta, exantema, mialgia, cefaléia e artralgia. Além do quadro clínico típico, manifestações atípicas como complicações neurológicas foram relatadas: meningo-encefalite, mielorradiculopatia, mielorradiculite, mielite, mieloneuropatia, síndrome de Guillain-Barre (GBS), entre outras. O diagnóstico é baseado em critérios clínicos, epidemiológicos e laboratoriais. Em relação aos sinais e sintomas da infecção pelo ZIKV, erupção cutânea (principalmente maculopapular), febre, artralgia, mialgia, cefaléia e conjuntivite são os mais comuns. Algumas epidemias que ocorreram recentemente na Polinésia Francesa e Brasil relataram condições mais severas, com envolvimento do sistema nervoso (GBS, mielite transversa, microcefalia e meningite). O tratamento para ZIKV e CHIK é sintomático, e o manejo das complicações neurológicas dependerá do tipo da afecção. Imunoglobulina venosa, plasmaférese, e pulsoterapia com corticosteróides são opções.

Neurological manifestations of Chikungunya and Zika infections / Manifestações neurológicas das infecções pelos vírus Zika e Chikungunya

ABSTRACT The epidemics of Chikungunya virus (CHIKV) and Zika virus (ZIKV) infections have been considered the most important epidemiological occurrences in the Americas. The clinical picture of CHIKV infection is characterized by high fever, exanthema, myalgia, headaches, and arthralgia. Besides the typical clinical picture of CHIKV, atypical manifestations of neurological complications have been reported: meningo-encephalitis, meningoencephalo-myeloradiculitis, myeloradiculitis, myelitis, myeloneuropathy, Guillain-Barré syndrome and others. The diagnosis is based on clinical, epidemiological, and laboratory criteria. The most common symptoms of ZIKV infection are skin rash (mostly maculopapular), fever, arthralgia, myalgia, headache, and conjunctivitis. Some epidemics that have recently occurred in French Polynesia and Brazil, reported the most severe conditions, with involvement of the nervous system (Guillain-Barré syndrome, transverse myelitis, microcephaly and meningitis). The treatment for ZIKV and CHIKV infections are symptomatic and the management for neurological complications depends on the type of affliction. Intravenous immunoglobulin, plasmapheresis, and corticosteroid pulse therapy are options.

RESUMO As epidemias provocadas pelo vírus Chikungunya (CHIK) e Zika vírus (ZIKV) têm sido consideradas as ocorrências epidemiológicas mais importantes da América. O quadro clínico da infecção por CHIK caracteriza-se por febre alta, exantema, mialgia, cefaléia e artralgia. Além do quadro clínico típico, manifestações atípicas como complicações neurológicas foram relatadas: meningo-encefalite, mielorradiculopatia, mielorradiculite, mielite, mieloneuropatia, síndrome de Guillain-Barre (GBS), entre outras. O diagnóstico é baseado em critérios clínicos, epidemiológicos e laboratoriais. Em relação aos sinais e sintomas da infecção pelo ZIKV, erupção cutânea (principalmente maculopapular), febre, artralgia, mialgia, cefaléia e conjuntivite são os mais comuns. Algumas epidemias que ocorreram recentemente na Polinésia Francesa e Brasil relataram condições mais severas, com envolvimento do sistema nervoso (GBS, mielite transversa, microcefalia e meningite). O tratamento para ZIKV e CHIK é sintomático, e o manejo das complicações neurológicas dependerá do tipo da afecção. Imunoglobulina venosa, plasmaférese, e pulsoterapia com corticosteróides são opções.