attach themselves to their surroundings. But the study suggests that when the cancer cells are floating, as they do during
metastasis, the integrins switch from their adhesion role to
take on an entirely new form of communication which has
never been seen before—“inside-in” signaling, in which integrins signal within the cell.
A new strategy could be to prevent the integrin from going
inside the cell in the first place. The researchers hope that
these insights could lead to the design of better therapies
against metastasis and more effective treatment combinations
that could prevent and slow both tumor growth and spread.
The team carried out part of their animal research work on
zebrafish embryos in order to implement the principle of 3Rs
(refine, reduce, replace) on their research on mice. Zebrafish
provide a similar tumor microenvironment to humans, meaning fewer tests need to be carried out in mice and any future
experiments in mice will have been optimized to have minimal
toxicity. They are aiming to reduce the number of mice used by
at least 90% percent and ultimately use zebrafish to completely replace the use of mice.
DIABETES REVERSAL AFTER BYPASS SURGERY LINKED TO
CHANGES IN GUT MICROBIOME
Studies have shown that bariatric surgery
can lead to remission of type 2 diabetes
mellitus (T2DM) in rodents and humans,
but this beneficial effect cannot be
explained solely by weight loss. In a new
study published in The American Journal
of Pathology, researchers investigating
gastric bypass in a mouse model of T2DM
confirmed that bypass surgery improves
glucose tolerance and insulin sensitivity. Interestingly, the
improved metabolism occurred in conjunction with changes in
gut microorganisms, suggesting a potential role for gut microbi-
ota in diabetes remission.
The research was performed in the T2DM mouse model that
mimics key symptoms including insulin resistance, high blood
levels of lipids, metabolic inflammation, and obesity. These
mice harbor genetic mutation in brain-derived neurotrophic
factor (Bdnf) leading to Bdnf deficiency. Bdnf is a member of
the neurotrophic family of growth factors and is a key regulator
of both brain function and metabolic balance.
Examination of the composition of bacteria and other microorganisms in the gut of mutated mice before and after bypass
surgery and in the control group, showed a decrease in pathogenic bacteria and an increase in beneficial microflora that
coincided with the onset of better glycemic control.
Inflammation, especially in white fat tissue and liver, is
thought to play an important role in obesity and T2DM. Eight
weeks after bypass surgery, significant reductions in inflammatory indicators occurred in the liver and fat tissue, although the
post-surgical anti-inflammatory effects occurred after insulin
SINGLE SPECIES OF GUT BACTERIA CAN REVERSE AUTISM-RELATED SOCIAL BEHAVIOR IN MICE
The absence of one specific species of gut bacteria causes social deficits in mice, researchers at Baylor College of
Medicine report June 16 in Cell. By adding this bacterial species back to the guts of affected mice, the researchers were
able to reverse some of the mice’s behavioral deficits, which
are reminiscent of symptoms of autism spectrum disorders
(ASDs) in humans. The investigators are now looking to
explore the effects of probiotics on neurodevelopmental disorders in future work.
The inspiration for the paper came from human epidemiological studies that have found that maternal obesity during
pregnancy could increase children’s risk of developing neurodevelopmental disorders, including ASDs. In addition, some
individuals with ASD also report recurring gastrointestinal
problems. With emerging research showing how diet can
change the gut microbiome and how gut microbes can influence the brain, the study authors suspected there could be a
In particular, the researchers believe that their work, which
uses a human-sourced bacterial species to promote oxytocin
levels and improve social behavioral deficits in deficient mice,
could be explored as a probiotic intervention for the treatment
of neurodevelopmental disorders in humans.
HOW A LOW-CALORIE DIET COULD EXTEND LIFESPAN
Overeating can lead to health issues
that can shorten one's life, such as
obesity, diabetes and heart disease. On
the other end of the spectrum, several
studies have shown that restricting cal-
orie intake below what a normal diet
would dictate may lead to a longer
life. In an animal study, scientists now report in ACS' Journal
of Proteome Research the metabolic reasons why these opposite
diets may lead to such differences in longevity.
Calorie restriction with proper nutrition seems to help
extend lifespans and delay the onset of age-related disorders by
reducing what are called reactive oxygen species in the body.
However, scientists still do not know the precise biochemical
changes the body undergoes during calorie restriction, and no
one has determined its long-term effects.
The research team divided mice into four dietary categories—low-fat, low-fat with calorie restriction, high-fat and
high-fat with calorie restriction—for more than a year. They
then used nuclear magnetic resonance analysis to examine the
metabolic effects in blood and urine samples.
The researchers found that calorie restriction had a much
bigger effect on metabolic outcomes than the amount of fat in
the diet. Mice on higher calorie diets had increased oxidative
stress, disturbed lipid metabolism, suppressed glycolysis and
altered gut-microbial metabolites compared to those on the