AMONG the essential amino acids,
leucine, isoleucine and valine
belong to a category of their own
called the branched-chain amino
acids (BCAAs).
Cats and dogs are incapable of
synthesising
adequate
amounts of these amino
acids, so dietary
intake is needed
to meet daily
requirements.
As a result, the
concentration of these three amino
acids in the blood is very dependent on
the diet that is being fed.
Leucine, isoleucine and valine
represent at least one-third of the
essential amino acids constituting
muscle proteins and they are the only
amino acids that are initially degraded
by muscles. These three amino acids
are unique among the essential amino acids because they are able to undergo
reversible transamination to enrich the
organism’s nitrogen pool.
Leucine, isoleucine and valine are
able to stimulate the synthesis of
proteins and slow protein degradation in muscles. This property has been
specifically attributed to leucine, as
it has proven to be as effective as a
mixture of the three BCAAs in doing
so.
Further research
In human medicine, numerous studies
have focused on the possibility of
nutritionally supporting the ageing effect on muscles by changing the
quantity and also the quality of
ingested proteins, aiming to optimise
protein intake and retention through
an improvement in amino acid
bioavailability for the muscle tissues.
Although the mechanisms for
the development of
sarcopaenia are not
clearly elucidated, age-
associated alterations in the muscle’s anabolic
response to nutritional
stimuli and a decline in
protein intake may be
significant contributing
factors.
The ageing muscle
is still able to respond
to amino acids, mainly
the essential BCAAs, which have been
shown to promote muscle protein
synthesis in older individuals.
It is likely that this is due to the
direct effect of leucine on the initiation of mRNA translation, which is still
present in older age, although at a
reduced level.
Leucine for senior pets
An increased level of BCAAs in
the diet may be beneficial for the maintenance of a
healthy and strong
muscle mass in the
older cat and dog.
As a result, Royal
Canin’s range of
Senior Consult diets
contain a higher
percentage of BCAAs
(leucine in particular)
to help maintain this
muscle mass and as
such BCAAs form a key component for the nutritional
management of cats and dogs with
sarcopaenia.
In summary, the nutritional response
dedicated to the senior cat and dog
often includes an enhanced BCAA
profile, especially regarding the levels
of leucine.
Together with regular veterinary
check-ups, an appropriate diet can help
senior cats and dogs continue to lead
happy and healthy lives.
- For further reading visit vet portal.royalcanin.co.uk (or vetportal.
royalcanin.ie for Ireland).
