Vision of LIFE - Volume 17 - No. 1

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Life Science News
Use of microRNAs for therapy of renal fibrosis
MicroRNAs (miRNA) are small non-coding RNA molecules which bind with complementary
sequences in mRNAs suppressing protein translation. They have the ability to bind to specific
regions in the 3′UTR of mRNA and repress gene expression through interaction with the RNA
induced silencing complex (RISC). MiRNAs are essential for renal development and homeostasis.
Renal fibrosis is a result of a significant kidney injury, in which the replacement of functioning
nephrons with scar tissue results in impaired renal function. Transforming growth factor
β (TGFβ) is the main cytokine involved in renal damage and fibrosis here, and its main
contribution to the process is to stimulate synthesis and accumulation of extracellular matrix.
The feature of miRNAs to target multiple mRNAs defines that targeting a particular miRNA
for therapy could stop fibrosis. MiR-21 is a miRNA very highly expressed in most tissue, has
its own promoter and is independently transcribed. MiR-21 expression is closely linked to
TGFβ signaling and consequently fibrosis. Many groups have shown in multiple cell types
that increases in miR-21 are induced by TGFβ stimulation. This increased expression of miR-
21 has been observed in multiple preclinical models of renal diseases. Treatment of diseased
kidneys of knockout (genetically modified) mice with the anti-MiRNA-21 has led to reduced
albuminuria, less fibrosis and inflammation, and improved survival. The severity of the renal
dysfunction was reduced. This shows how a particular miRNA
for therapy could have a dramatic effect on a disease process.
Source: Denby, L., Baker, A.H. (2016) Targeting non-coding RNA for the therapy of renal
disease. Current Opinion in Pharmacology, Volume 27, April 2016, 70–77.
Science
Effects of mobile phone radiation on the brain
The public concern about the potential health hazards induced
by radiofrequency (RF) radiation has been growing with the rapid
development of electrical technologies. A study was performed
to investigate the effect of 1800 MHz RF radiation emitted from
a mobile phone on the rat’s brain. Twenty rats were exposed to
1800 MHz emitted from a mobile phone with an SAR value of
Figure 1. Mobile phone radiation
might be hazardous to the brain.
0.6 W/kg for two hours a day during three months. Another twenty rats were observed as a
control group. The brain tissues were collected afterwards and used in several studies.
The rats exposed to RF radiation had a significant elevation in malondialdehyde (MDA) content,
which is a marker for oxidative stress. A significant reduction in antioxidant parameters was
visible too.
This means exposure to mobile phone radiation induced oxidative damage to the brain and
might induce apoptotic changes to brain tissue. The study showed chronic exposure to mobile
phone radiation also induced severe histological alterations. These results suggest that direct
chronic exposure to mobile phone radiation can cause severe biochemical and histopathological
changes in the brain.
Source: Hussein, S., El-Saba, A.-A., Galal, M.K. (2016) Biochemical and histological studies on adverse effects of mobile phone
radiation on rat’s brain. Journal of Chemical Neuroanatomy, Volume 78, May 2016, 10-19.
Leanne van Bentem