Melatonin protects mice infected with Venezuelan equine encephalomyelitis virus.

The research focuses on how the administration of melatonin reduces the fatality rate and slows down the progression of disease in mice infected with the Venezuelan equine encephalomyelitis virus.

Overview of the research

• The study aimed to understand how the administration of Melatonin (MLT) can affect the mortality rate and progress of the disease in mice infected with Venezuelan equine encephalomyelitis (VEE) virus.
• Specifically, the researchers examined the consequences of MLT administration, both in terms of mortality rates and disease evolution, in VEE-infected mice.

Findings of the Research

• It was noted that MLT significantly reduces mortality rates, from a staggering 100% to just 16%, by merely increasing the dosage to 1000 micrograms. Thus, the onset of the disease, and ultimately death, is delayed by several days.
• The analyses show high levels of VEE antibodies in surviving mice, specifically after seven weeks of virus inoculation. This is indicative of the organism’s immune response towards the pathogen.

Protective Effects of Melatonin

• The examination shows that MLT consequently reduces the amounts of VEE virus in the blood and brain of infected mice, thereby enhancing their chances of survival.
• The beneficial effects of MLT increase when the duration of pre-treatment is extended from 3 to 7 or 10 days before virus inoculation.
• The treatment with MLT does not impact the serum levels of interleukin-2, an important cytokine in the immune system.
• Moreover, the serum levels of interferon-gamma were found to be increased in control mice that received MLT and also in infected mice, regardless of MLT treatment.
• Interestingly, it was noticed that in non-infected mice receiving MLT, there was a hike in interleukin-4 concentration, but this was not observed in infected mice irrespective of them receiving the treatment.
• Administrating MLT was also noted to reduce cellular destruction typically brought about by the VEE virus in culture plates of chicken embryo fibroblasts.

Implications of the Study

• The findings revealed the protective effects of MLT, thus fostering further exploration into its potential utilization for treating humans and equines infected with the VEE virus.
• The research underscores the efficacy of MLT in terms of reducing mortality, seroconversion, and protection of cell destruction in VEE virus-infected mice. This opens up possibilities of devising therapeutic interventions using the hormone.