Protein that can mean life or death for cells
identified
London:
Scientists have identified a protein that plays a crucial role in correctly
measuring stress levels, and also makes sure the pathways of cell repair or
cell death in the body are effective.
Each
cell in an organism has a sensor that measures the health of its
"internal" environment, researchers said.
This
"alarm" is found in the endoplasmic reticulum (ER), which is able to
sense cellular stress and trigger either rescue responses or the death of the
cell.
A
team from the Institute for Research in Biomedicine (IRB), in Barcelona, found
some of the molecular mechanisms that connect the protein Mitofusin 2 (Mfn2) to
endoplasmic reticulum stress.
When
the scientists removed Mfn2 from the cell under conditions of cell stress, the
endoplasmic reticulum responded by over-activating the repair pathways.
By
doing so, it contradictorily functioned worse, reducing the capacity of cells
to overcome the stress insult and promoting to a lesser degree apoptotic cell
death.
"When
Mfn2 is removed, the cellular stress response pathways are completely
disrupted," said Antonio Zorzano, coordinator of IRB's Molecular Medicine
Programme.
The
study investigated the relationship between mitochondria and the endoplasmic
reticulum, and indicated that changes in mitochondria, caused by the loss of
the Mfn2 protein, directly affect the endoplasmic reticulum function.
"We
have shown that Mfn2 is important for cell viability and has implications for
numerous diseases, such as neurodegeration, cancer, cardiovascular disease, in
addition to diabetes," said postdoctoral researcher Juan Pablo Munoz,
first author of the study.
"The
fact that we can modulate cell damage response with Mfn2 opens a wide window of
possible therapeutic avenues for further study," said Munoz.
Munoz
explained that tumour cells don't activate cell death properly and proliferate
uncontrolled.
"Cancer
cells have already been noted to have low Mfn2 levels, and if we could increase
such levels, we would be able to promote apoptosis," Munoz said.
21.09.2013
New islet
cell transplant may free diabetics from painful insulin injections
Washington:
Researchers have revealed that islet transplantation can produce substantially
improved results for patients with type 1 diabetes, as it helps increase levels
of insulin production to the degree that patients are able to discontinue daily
insulin injections.
In
islet transplantation, clusters of insulin-producing cells known as islets are
transplanted from a donor pancreas into another person's liver, while allowing
the harvested cells a short period of rest prior to transplant.
The
study found that the new approach may also offer a more durable alternative to
a whole pancreas transplant.
Participants
in the new study by researchers at the Perelman School of Medicine at the
University of Pennsylvania received islet cells isolated from the pancreas of
organ donors to help their bodies produce insulin, the life-sustaining hormone
responsible for absorbing glucose from the blood.
In
the study, investigators used an advanced technique to isolate and harvest
islet cells from donor pancreases. Unlike prior methods in which isolated islet
cells were immediately transferred to the recipient, the new technique allowed
the extracted cells to rest in a controlled environment for three days prior to
transplant.
Ultimately,
the resting period also resulted in a more efficient process by allowing
investigators to use fewer islet cells than previous methods which required
cells from two or more donor pancreases achieve similar results. Despite fewer
islet cells being transplanted, the new approach resulted in significantly
improved islet cell function.
The
study is published in the journal Diabetes.
21.09.2013
When given a choice of
being right or being kind, choose
kind
Wayne Dyer
No comments:
Post a Comment