Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Japanese Encephalitis Virus causes 'Double Trouble' to Brain

Japanese encephalitis (JE), commonly known as brain fever, is one of the prevalent mosquito-borne encephalitis in India and entire South East (SE) Asia.

Besides resulting in thousand fatalities each year, JE virus (JEV) infection causes prominent neurological sequelae in approximately one-third of the survivors. Even those patients in the good recovery group commonly encounter psychiatric problems, which include mental retardation, learning disabilities, speech and movement disorders and behavioural abnormalities.

Recent research in National Brain Research Center, Manesar, India by Dr. Anirban Basu and his graduate student, Sulagna Das have shown that JE virus damages the brain in two ways, by not only killing brain cells but by preventing the birth of new cells from neural stem/progenitor cells (NPC) and depleting the NPC pool in the brain. “It's a double hit to the brain, the JE virus causes brain injury by killing neurons as well as prevents its repair” lead researcher and the senior author of the work Anirban Basu said in a statement.

The children are more vulnerable targets of this virus, which causes massive neuronal loss in the Central Nervous System. “Children are at a dynamic stage of brain development, hence infection at this stage can have devastating effects on mental functions later in life. Our study has tried to explore how JEV infection leads to development of long-term cognitive deficits in the survivors”, says Dr. Anirban Basu who has been working in the neurobiology of JEV infection for the past 4 years. These findings have been published online in a paper in Journal of Neurochemistry for inclusion in a future issue of the journal.

"The breakthrough here is that the JE virus prevents neural stem and progenitor cells in the brain from dividing; it hangs them up," Basu said. "It's the first time that a mosquito-borne virus has ever been shown to affect neural stem cells." The progressive infection in these cells eventually results in decrease in proliferation ability, providing a possible explanation for their diminished pool upon infection,” said Basu. He also went on to state, “The neurological and cognitive deficits in the JE survivors could be related to the drop in NPC cells in the neurogenic region of the brain called the subventricular zone”.

Neural stem/progenitor cells are the saviours of the brain following any insult or infection and via the process of neurogenesis help the recovery process. These cells have the ability to self-renew over lifetime and generate both neurons and glia, which make up the CNS. The initial work with neural stem cells in cell culture dishes interestingly showed that unlike neurons, these stem cells are a resilient population and do not undergo robust cell death upon JEV infection. Instead, the virus lowers the NPC pool by disrupting the growth kinetics and the proliferative ability of these cells. The study was extended in mouse models of JE, where a significant decrease in the actively proliferating NPCs was observed in the subventricular zone or the primary niche of post-natal neurogenesis.

The possible mechanism by which JEV reduces the proliferating NPC pool was also worked out by the scientists utilising the cell cycle studies. Sustained proliferation is a key feature of NPCs, which have to pass through various cell cycle checkpoints and phases of division. Upon JEV infection, these cells halt at the resting phase and fail to proceed to the dividing S-phase. Both cell culture and animal studies indicate that JEV inhibits the DNA synthesis in these cells during progressive infection and induces cycle arrest in them. The researchers went on to show that the virus leads to increased expression of certain checkpoint proteins that block the transition of cells to S-phase, thus preventing the NPCs from multiplying.

Over the years, JE has become a major cause of mortality and morbidity in wide areas of SE Asia. The very high incidence of permanent and disabling neurological sequelae has considerable socioeconomic impact. “Knowing the mechanism, we can start to approach this therapeutically” Basu said. "This indicates that we might eventually treat this form of neurological and psychiatric problems by either ramping up brain repair or protecting the repair mechanism," Das added.

Anirban Basu | alfa
Further information:

More articles from Health and Medicine:

nachricht NIH scientists describe potential antibody treatment for multidrug-resistant K. pneumoniae
14.03.2018 | NIH/National Institute of Allergy and Infectious Diseases

nachricht Researchers identify key step in viral replication
13.03.2018 | University of Pittsburgh Schools of the Health Sciences

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

Im Focus: Radar for navigation support from autonomous flying drones

At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.

Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

International Virtual Reality Conference “IEEE VR 2018” comes to Reutlingen, Germany

08.03.2018 | Event News

Latest News

Wandering greenhouse gas

16.03.2018 | Earth Sciences

'Frequency combs' ID chemicals within the mid-infrared spectral region

16.03.2018 | Physics and Astronomy

Biologists unravel another mystery of what makes DNA go 'loopy'

16.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>