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Researchers funded by FD Hope recently published some very
promising news for FD families whose children suffer the ravages
of autonomic crises, which cause intractable cyclical vomiting
or retching, dangerously high blood pressure and heart rate.
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Drs.
Sylvia Anderson and Berish Rubin of Fordham University’s
Laboratory for Familial Dysautonomia Research have taken their
research a significant leap forward. Drs. Anderson and Rubin
previously discovered the FD gene, and then showed that taking
the nutritional supplements tocotrienols and EGCG increases
quantities of the normal form of the protein IKAP in those with
FD, a protein that would otherwise be present in dangerously low
amounts. In the online August 2005 issue (in print, October
2005) of Biochemical and Biophysical Research Communica-tions,
Anderson and Rubin reported that FD patients have much lower
than normal levels of MAO-A, an isoenzyme that degrades
neurotransmitters such as norepinephrine, but that those who
take tocotrienols have higher levels of MAO-A and 80% of those
in a study by Anderson and Rubin (unpublished) reported fewer
crises, thus identifying a clue to potentially preventing some
crises. |
 Dr
Berish Rubin and Dr Sylvia Anderson (from left) pay a
visit to Michelle Berkovitz and her children, Zoe and Eli,
who has FD. |
This
gives FD patients something very much in common with people who
take a class of anti-depressant drugs called MAO inhibitors (MAOIs),
and a map for preventing some crises. People who take MAOI
anti-depressants must be very careful about the foods they eat
and the other medicines they take, because certain foods (those
containing tyramine) and medicines (including seratonergic and
sympathomimetic agents) trigger life-threatening autonomic
crises that resemble remarkably those experienced by people with
FD.
MAO-A
plays a critical role in the biochemical pathways associated
with the body’s stress response, particularly with respect to
the breakdown of norepinephrine after stress induces its
production. Without enough MAO-A available to break it down,
norepinephrine remains, continually stimulating the sympathetic
nervous system, with the potential to cause autonomic crisis.
MAO-A
also is involved in metabolizing a dietary compound called
tyramine, which is formed when the amino acid tyrosine ages. If
MAO-A levels are low, due to FD or the use of MAOIs, then the
tyramine ingested from food can reach dangerous amounts,
triggering autonomic crisis. Anderson and Rubin reported that
they were aware of incidents in which FD patients suffered
autonomic crises after ingesting foods high in tyramine,
including canned cranberries and an enteral formula.
Anderson
and Rubin are continuing their investigation into why IKAP and
MAO-A levels rise together in FD patients taking tocotrienols.
They believe that IKAP may be capable of regulating MAO-A gene
expression.
The
researchers are also interested in other parallels between the
symptoms of those with FD and the side effects in those who take
MAOIs, such as dizziness upon standing up. In addition, they
note that low MAO-A levels may play a part in FD symptoms other
than crisis. For example, MAO-A is found in parts of the brain
that control growth, gait, posture, muscle tone, coordinated
movement, blood pressure, cardiac function, responsiveness to
oxygen deficiency in the body, perception of pain, and the
elimination functions. In brain tissue taken from FD patients,
the levels of MAO-A are lower than normal.
Click
here for information on tyramine avoidance for dietary
guidelines that may help an FD patient avoid autonomic crises.
An FD patient’s doctor can advise on medicines, such as
over-the-counter decongestants, that are avoided by those who
take MAOIs and should perhaps be avoided by those with FD.
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