Re:Congenital Zika syndrome with arthrogryposis: retrospective case series study. Aleem M A.BMJ 2016;354:i3899

Research

Congenital Zika syndrome with arthrogryposis: retrospective case series study

BMJ 2016; 354 doi: http://dx.doi.org/10.1136/bmj.i3899 (Published 09 August 2016)

Cite this as: BMJ 2016;354:i3899

Rapid response

Re: Congenital Zika syndrome with arthrogryposis: retrospective case series study

Zika virus is a severely pathogenic virus causing many brain malformations, several birth defects and many neurological problems, including microcephaly in neonates. Two mechanisms hav been postulated for the development of central nervous malformations due to zika virus.

Zika virus activates the TLR3 (Toll Like Receptor 3) molecule normally used to defend against invading viruses in human cells.Then this hyper-activated TLR3 turns off genes that stem cells need to specialise into brain cells and turns on genes that trigger cell cell death, leading to various brain malformations. If this mechanism is proved, it will help to develop new therapies like TLR3 inhibitors against zika virus infection associated brain malformations.

The second possible mechanism by which zika viral infection causes brain malformations in the fetuses of zika virus infected women is interference with retinoic acid signaling by introducing its genome sequence repeats (called Retinoic Acid Response Elements or simply RARE consensus repeats) into the developing brain cells of the fetus. Retinoic acid (a metabolite of vitamin A) is one of the earliest factors for regulating the anteroposterior axis of neural tube and positioning of structures in the developing brain through RARE consensus sequence in promoter regions of retinoic acid-dependent genes.

Based on this, it may be helpful to design vaccines and other newer and effective treatments against zika viral infection and its complications in the near future.

Competing interests: No competing interests

11 August 2016

M A Aleem

Neurologist

ABC Hospital.Apollo Hospitsl and Dhanalakhmi Srinivasan Medical college and Hospital

Annamaalainagar Trichy 620018.Apollo Hospital Trichy 620010.Apollo clinic 620018. Dhanalakhmi Srinivasan Medical College and Hospital Siruvachure Perambalur 631113.Tamiknadu India

@drmaaleem