The original
idea of this blog was to try to keep complicated things as simple as possible,
so at times things may get over-simplified.
This post starts out simple and then gets rather involved in oxidative
stress.
When people
think about genes, they are nearly always thinking about the “blueprints” that
are encoded on your DNA. As it turns out
only about 5% of your DNA is dedicated to this function; this 5% is contained
in the exome.
Much autism
research is dedicated to finding faulty “blueprints” that might account for
autism. There are now several hundred so
called “autism genes”, where an error in the “blueprints”, means that the
associated protein is not produced to its intended specification.
We also have
seen that genetic defects just lead to a possibility
of something going wrong. A “faulty
gene” creates the possibility of a specific dysfunction happening, it does not
mean 100% that it will happen.
Partial dysfunctions and partial deficiency
We also saw
that even when a single gene dysfunction, like for fragile-X, occurs it does
not always cause a catastrophic failure, rather it produces a spectrum from
mild to severe.
This point
is important since it seems in autism there can often be “partial dysfunctions”
leading to “partial deficiencies”. This
is just a less severe form of the “rare” total dysfunctions. The growing list of examples includes partial
biotinidase deficiency, partial glutathione reductase deficiency and partial glutathione peroxidase deficiency. Today we will also encounter ferritin (iron
storage) partial
deficiencies. In a future post we will
look the vitamin B12 partial dysfunction that occurs in about a quarter of
schizophrenia and autism cases.
This then
leads us to the subject of gene expression, which means how much, where, when and
how often a gene is turned “on”. This is
actually what really matters, since even perfectly good genes, when
over-expressed, can do great damage. We
saw that in the case of Down Syndrome there is about 50% over expression in up
to 300 genes. In the case of Down
Syndrome the reason for this overexpression lies in the exome. In effect there is a double set of blueprints
for those 300 genes.
Within the
remaining 95% of your DNA are so-called enhancers and silencers. Their job is to determine which genes are
turned on (enhancers) or turned off (silencers) in which part of the body. So a gene might encode a calcium channel, but
that calcium channel should only be in certain parts of the body and only to a
certain degree. We need the correct
clean blueprint and we need it applied in the right part of the body and only
to the desired extent.
I was very
pleased to see that some scientists have started to look at the role of
enhancers in autism. I have already
noticed that some substances that are known to affect gene expression are
particularly effective in autism. This
suggests to me that in some types of autism, the problem may actually be simply
in gene expression rather than any faulty genetic “blueprint”.
Now the
science of enhancers and particularly silencers is still at the emerging stage,
but the research showed that in at least 100 locations, there were significant
anomalies in those with autism.
This is an easy to read summary of the research paper below.
Abstract
Despite major progress in identifying
enhancer regions on a genome-wide scale, the majority of available data are
limited to model organisms and human transformed cell lines. We have identified
a robust set of enhancer RNAs (eRNAs) expressed in the human brain and
constructed networks assessing eRNA-gene coexpression interactions across human
fetal brain and multiple adult brain regions. Our data identify brain region-specific eRNAs and show
that enhancer regions expressing eRNAs are enriched for genetic variants
associated with autism spectrum disorders.
We also have
the removable markers on the 5% of DNA that cause epigenetic changes. This is another way of turning on or off
specific genes. These markers can be
caused by environment factors like smoking, or even stress, these markers are
potentially both removable and inheritable.
The emerging
science of Proteomics is the study of gene expression itself, so it is
measuring all the proteins that the genes actually produced.
Limits of Genetic Testing
So while in
some cases genetic testing of the 5% of DNA usually examined may indeed be
useful, if your problem was in the other 95% of DNA it will not help.
To be useful
in autism you would need to measure gene expression in the brain or the local
activity of the enhancers/silencers, since it varies throughout the body. In the Australian study above they measured
the enhancer activity in the brain, by looking for the special enhancer molecules
the enhancers produce.
This is all
way beyond the scope of this blog.
However when
I see “safe” substances like Sulforaphane, Epicatechin and even statins that
are known to affect the expression of multiple genes, I take note.
Steroids
also affect gene expression, but great care has to be taken with steroids.
Statins have
numerous interesting effects in the brain and in cancer cells. In autism they have an effect on PTEN and
BCL2 for example.
The observed impact of pravastatin
on gene expression may explain the pleiotropic effects of statins when they are
used as adjuvants in chemotherapy and suggests impact on gene expression as a possible cause of
side effects from statin use.
As pointed
out in the last paper, changing gene expression can be bad as well as good. It all depends where you are starting from
and what genes you want to enhance/silence.
Other therapies to modify gene
expression
Today’s
scientific knowledge does not always allow us to target the expression of
specific genes, this very much remains future science.
However, the
remarkable effects of some substances, in some people, does suggest some
options. As is often the case this takes
us back to oxidative stress, which does seem to affect many conditions and is
quite well studied. There is no shortage of anecdotal evidence.
We know from
the research that oxidative stress is ever-present in autism and that people
with autism are particularly sensitive to it.
One
substance previously mentioned in this blog, epicatechin, is known to change
the expression of many genes including STAT1, MAPKK1, MRP1, and FTH1,
which are involved in the cellular response to oxidative stress.
Ferritin
Rather off
subject the FTH1 gene encodes the heavy subunit of ferritin, the major intracellular iron
storage protein.
Children with autism spectrum disorders had significantly lower
ferritin levels compared with controls
Within the autism spectrum disorders population, median ferritin levels
were significantly lower in patients with poor sleep efficiency (7 ng/mL)
versus those with normal sleep efficiency (29 ng/mL) (P = 0.01).
Low ferritin
would indicate an iron storage problem and likely anemia/anaemia.
Low ferritin
has many effects, including surprisingly, poor sleeping patterns.
Is it such a
surprise that a cup of cocoa (epicatechin) before bed used to be given to
ensure a good night’s sleep? (all via
FTH1, I presume)
Perhaps poor
sleep in autism is just another consequence of oxidative stress?
MOCOS
In the
recent paper on MOCOS:-
I noted
that:-
Furthermore, we found that MOCOS misexpression
induces increased oxidative-stress sensitivity.
MOlybdenum COfactor
Sulfurase (MOCOS), is an enzyme involved in purine metabolism and a newly
identified player in ASD. MOCOS appears to be downregulated in autism and this
has multiple effects, one being increased sensitivity to oxidative stress.
Seemingly unknown
to the French MOCOS researchers, there already is a therapy:-
Since I do
not have any of the above biosynthetic
precursor
at
hand, but I do have high flavanol cocoa in the kitchen, it is time to look again at epicatechin.
Epicatechin
There are
two very similar substances catechin and epicatechin; both are flavonoids. Both affect gene expression and both seem to
have numerous good properties.
Epicatechin
is found in large quantities in mildly processed cocoa, which catechin in found
in large quantities in certain types of Chinese tea.
We saw in an
earlier post that Mars, the chocolate company, has invested substantially in
the science of cocoa and its flavonoids. They have just signed a 5 year research contract with Harvard.
Catechin
affects the fat metabolism and is therefore a potential therapy for
obesity. Oolong tea has been shown to
have this effect, but you do need to drink a great deal of it.
CONCLUSIONS:
Oolong
tea could decrease body fat content and reduce body weight through improving
lipid metabolism. Chronic consumption of oolong tea may prevent against
obesity.
ABSTRACT Various health benefits of the cocoa flavanol
(-)-epicatechin (EC) have been attributed to its antioxidant and
anti-inflammatory potency. In the present study we investigated whether EC is
able to prevent deterioration of the anti-inflammatory effect of the
glucocorticoid (GC) cortisol in the presence of oxidative stress. It was found
that cortisol reduces inflammation in differentiated monocytes. Oxidative
stress extinguishes the anti-inflammatory effect of cortisol, leading to
cortisol resistance. EC reduces intracellular oxidative stress as well as the
development of cortisol resistance. This further deciphers the enigmatic mechanism
of EC by which it exerts its anti-inflammatory and antioxidant action. The observed effect of the cocoa flavanol EC will especially be of
relevance in pathophysiological conditions with increased oxidative stress and
consequential GC resistance and provides a fundament for the rational use of
dietary antioxidants
Abstract
Background:
Consumption of flavonoid-rich beverages, including tea and red wine, has been
associated with a reduction in coronary events, but the physiological mechanism
remains obscure. Cocoa can contain extraordinary concentrations of flavanols, a
flavonoid subclass shown to activate nitric oxide synthase in vitro.
Objective:
To test the hypothesis that flavanol-rich cocoa induces nitric-oxide-dependent
vasodilation in humans.
Design:
The study prospectively assessed the effects of Flavanol-rich cocoa, using both
time and beverage controls. Participants were blinded to intervention; the
endpoint was objective and blinded.
Methods:
Pulse wave amplitude was measured on the finger in 27 healthy people with a
volume-sensitive validated calibrated plethysmograph, before and after 5 days
of consumption of Flavanol-rich cocoa [821 mg of flavanols/day, quantitated as
(−)-epicatechin, (+)-catechin, and related procyanidin oligomers]. The specific
nitric oxide synthase inhibitor, NG-nitro-l-arginine methyl ester (l-NAME) was
infused intravenously on day 1, before cocoa, and on day 5, after an acute
ingestion of cocoa.
Results:
Four days of flavanol-rich cocoa induced consistent and striking peripheral
vasodilation (P
= 0.009). On day 5, pulse wave amplitude exhibited a large additional acute
response to cocoa (P = 0.01). l-NAME completely reversed this vasodilation (P =
0.004). In addition, intake of flavanol-rich cocoa augmented the vasodilator
response to ischemia. Flavanol-poor cocoa induced much smaller responses (P =
0.005), and none was induced in the time-control study. Flavanol-rich cocoa
also amplified the systemic pressor effects of l-NAME (P =
0.005).
Conclusion:
In healthy humans, flavanol-rich cocoa induced vasodilation via activation of
the nitric oxide system, providing a plausible mechanism for the protection
that flavanol-rich foods induce against coronary events.
Abstract
The Kuna Indians, who reside in an archipelago on the Caribbean
Coast of Panama, have very low blood pressure (BP) levels, live longer than
other Panamanians, and have a reduced frequency of myocardial infarction,
stroke, diabetes mellitus, and cancer—at least on their death certificates. One
outstanding feature of their diet includes a very high intake of flavanol-rich
cocoa. Flavonoids in cocoa activate nitric oxide synthesis in healthy humans.
The possibility that the high flavanol intake protects the Kuna against high
BP, ischemic heart disease, stroke, diabetes mellitus, and cancer is
sufficiently intriguing and sufficiently important that large, randomized
controlled clinical trials should be pursued.
Glutathione reductase (GR) and (partial) Glutathione
reductase deficiency
Glutathione reductase (GR) catalyzes
the reduction of glutathione disulfide (GSSG) to the
sulfhydryl form glutathione (GSH), which is a
critical molecule in resisting oxidative stress and maintaining the reducing
environment of the cell.
Glutathione reductase reduces one mole of GSSG to two
moles of GSH.
Some patients exhibit deficient levels of glutathione activity as a result of not consuming enough riboflavin in their diets. Riboflavin is a precursor for FAD, whose reduced form donates two electron to the disulfide bond which is present in the oxidized form of glutathione reductase in order to begin the enzyme's catalytic cycle.
In 1999, a study found that 17.8% of males and 22.4% of females examined in Saudi Arabia suffered from low glutathione reductase activity due to riboflavin deficiency.
Abstract
Glutathione reductase (GR) is a
ubiquitous enzyme required for the conversion of oxidized glutathione (GSSG) to
reduced glutathione (GSH) concomitantly oxidizing reduced nicotinamide adenine
dinucleotide phosphate (NADPH) in a reaction essential for the stability and
integrity of red cells. Mutations in the GR gene and nutritional deficiency of
riboflavin, a co-factor required for the normal functioning of GR, can cause GR
deficiency. We conducted a study on 1691 Saudi individuals to determine the
overall frequency of GR deficiency and to identify whether the deficiency
results from genetic or acquired causes or both. The activity of GR was
measured in freshly prepared red cell haemolysate in the presence and absence
of flavin adenine dinucleotide (FAD) and the activity coefficient (AC) was
determined. Samples with low GR activity (> 2.0 IU/g haemoglobin) both in
the presence and absence of FAD and an AC between 0.9 and 1.2 were considered
GR-deficient. Samples with AC > or = 1.3 were considered
riboflavin-deficient. The
overall frequency of partial GR deficiency was 24.5% and
20.3% in males and females respectively. In addition, 17.8% of males and
22.4% of females suffered from GR deficiency due to riboflavin deficiency. This could be easily corrected
by dietary supplementation with riboflavin. No cases of severe GR
deficiency were identified.
Regular
readers may recall something very similar with biotin and its enzyme
biotinidase. Biotinidase deficiency is
supposedly such a rare metabolic disorder that it is no longer screened for;
however, in an autism study in Crete, Greece it was found that partial
biotinidase deficiency was quite common.
Glutathione peroxidase
Glutathione peroxidase (GPx) is the general name of an enzyme
family with peroxidase
activity whose main biological role is to protect the organism from oxidative
damage.
The biochemical function of glutathione peroxidase is to
reduce lipid hydroperoxides to their corresponding alcohols and to reduce free
hydrogen peroxide to water.
In earlier posts on anti-oxidants we saw the following presentation
from the German scientist. Note Glutathione
(GSH) peroxidases, left halfway down
Glutamate Cysteine Ligase (GCL)
GSH, and by extension GCL, is critical to cell survival.
Nearly every eukaryotic cell, from plants to yeast to humans, expresses a form of the GCL protein for the purpose of synthesizing GSH
Dysregulation of GCL enzymatic
function and activity is known to be involved in the vast majority of human
diseases, such as diabetes, Parkinson's disease, Alzheimers disease, COPD,
HIV/AIDS, and cancer. This typically involves impaired function leading to
decreased GSH biosynthesis, reduced cellular antioxidant capacity, and the
induction of oxidative stress.
Measuring GR, GPx, GCL in Autism
Fortunately
somebody has already measured GR, GPx and GCL in autism, and not surprisingly
they are all dysfunctional. The paper is
by the Chauhans, who already feature on my Dean’s list of researchers.
In
the cerebellum tissues from autism (n=10) and age-matched control subjects
(n=10), the activities of GSH-related enzymes glutathione peroxidase (GPx),
glutathione-S-transferase (GST), glutathione reductase (GR), and glutamate
cysteine ligase (GCL) involved in antioxidant defense, detoxification, GSH
regeneration, and synthesis, respectively, were analyzed. GCL
is a rate-limiting enzyme for GSH synthesis, and the relationship between its
activity and the protein expression of its catalytic subunit GCLC and its
modulatory subunit GCLM was also compared between the autistic and the control
groups. Results showed that
the activities of GPx and GST were significantly decreased in autism compared
to that of the control group (P<0.05). Although there was no significant difference in GR
activity between autism and control groups, 40% of autistic subjects showed
lower GR activity than 95% confidence interval (CI) of the control group.
GCL activity was also
significantly reduced by 38.7% in the autistic group compared to the control
group (P=0.023), and 8 of 10 autistic subjects had values below 95% CI of the
control group. The
ratio of protein levels of GCLC to GCLM in the autism group was significantly
higher than that of the control group (P=0.022), and GCLM protein levels were
reduced by 37.3% in the autistic group compared to the control group. A
positive strong correlation was observed between GCL activity and protein
levels of GCLM (r=0.887) and GCLC (r=0.799) subunits in control subjects but
not in autistic subjects, suggesting that regulation of GCL activity is
affected in autism. These
results suggest that enzymes involved in GSH homeostasis have impaired
activities in the cerebellum in autism, and lower GCL activity in autism may be
related to decreased protein expression of GCLM.
GCLM
referred to above is Glutamate-cysteine ligase, it is the first rate
limiting enzyme of glutathione synthesis, it is encoded by the GCLM
gene. This is an enzyme/ gene you would want to upregulate.
https://en.wikipedia.org/wiki/GCLM
Fortunately
we can upregulate GPx enzyme activity with catechin or epicatechin.
Effects of catechin
and epicatechin on superoxide dismutase and glutathione peroxidase
activity, in vivo
Abstract
OBJECTIVES:
The objective of this study was to
investigate the effects of catechin and epicatechin on the activity of the
endogenous antioxidant enzymes superoxide dismutase (SOD) and glutathione
peroxidase (GPx) (as well as the total antioxidant capacity (TAC)) of rats
after intra-peritoneal (i.p.) administration.
METHODS:
Twenty-four Wistar rats were randomly
divided into two groups: the experimental group which was administered daily
with a 1:1 mixture of epicatechin and catechin at a concentration of 23 mg/kg
body weight for 10 days and the control group which was injected daily with an
equal amount of saline. Blood and urine samples were collected before and after
the administration period, as well as 10 days after (follow-up).
RESULTS:
Intra-peritoneal administration of
catechins led to a potent decrease in GPx levels and a significant increase in
SOD levels. TAC was significantly increased in plasma and urine. Malonaldehyde levels
in urine remained stable. In the animals treated with catechins, SOD activity
showed a moderate negative correlation with GPx activity.
DISCUSSION:
Boosting
the activity of the antioxidant enzymes could be a potential adjuvant approach
for the treatment of the oxidative stress-related diseases.
The objective of this study was to determine
whether i.p. administration of catechin and epicatechin could affect the
activity of the antioxidant enzymes, SOD and GPx, as well as the TAC in RBCs,
blood plasma, and urine.
The antioxidant enzymes are agents that promote
reactions for the removal of reactive species (e.g. O2•,.H2O2,
etc.). They constitute the first line of
defense against oxidative stress. In conditions of
increased oxidative stress, the upregulation of the enzyme activity or even, a
possible protection of the enzymes’ substrate
could be of great importance.
Oxidative stress disturbing homeostasis can be
resolved by the application of catechins and epigallocatechin gallate (EGCG)18
and there is growing evidence that, the protection, offered by flavonoids and
their in vivo metabolites, is not mediated primarily by
H-donating antioxidant processes, but is likely to be partly mediated through
specific actions, within signaling pathways.
Catechin and
epicatechin administration modulated the activity of SOD and GPx but the
overall TAC of the RBCs and of the rat’s plasma
remained stable.
Catechins are considered as potent antioxidants
and many of their biological actions have been attributed to that. It would
have been expected that since catechins are potent antioxidants in
vitro, they would have exerted their classical hydrogen-donating antioxidant
activity leading to an increase in TAC; as it is seen in the TAC of plasma. The modulation of the enzymes
activity may provide evidence that, catechins exert their primary antioxidant
activity by specific action within specific molecular pathways, rather than as
scavengers of free radicals.
Oxidative stress is a prominent feature of many
acute and chronic diseases and even of the normal aging process. The normal
function of the antioxidant enzymes guarantees the preservation of cell
integrity and thus they can be considered as potential therapeutic targets of
oxidative stress-related diseases.
Various antioxidants are available for therapeutic
use but most of them have failed in clinical studies of diseases correlated
with oxidative stress. Our
results suggest that catechins exert their activity not only by H-donating
antioxidant processes but likely through mechanisms and pathways that directly or indirectly regulate
the expression of the enzymatic antioxidants.
The
understanding of these pathways could be important, in developing
pharmacological strategies against oxidative stress-related diseases.
For those with autism plus GI issues / ulcerative colitis :-
Abstract
Background. This study was pathway of
(−)-epicatechin (EC) in the prevention and treatment of intestine inflammation
in acute and chronic rat models. Methods. Intestine inflammation was induced in
rats using TNBS. The morphological, inflammatory, immunohistochemical, and
immunoblotting characteristics of colon samples were examined. The effects of
EC were evaluated in an acute model at doses of 5, 10, 25, and 50 mg/kg by
gavage for 5 days. The chronic colitis model was induced 1st day, and treated
for 21 days. For the colitis relapse model, the induction was repeated on 14th.
Results. EC10 and EC50 effectively reduced the lesion size, as assessed
macroscopically; and confirmed by microscopy for EC10. The glutathione levels
were higher in EC10 group but decreased COX-2 expression and increased cell
proliferation (PC) were observed, indicating an anti-inflammatory activity and
a proliferation-stimulating effect. In the chronic colitis model, EC10 showed
lower macroscopic and microscopic lesion scores and increase in glutathione
levels. As in the acute model, a decrease in COX-2 expression and an increase
in PC in EC10, the chronic model this increase maybe by the pathway EGF
expression. Conclusion.
These results confirm the activity of EC as an antioxidant that reduces of the
lesion and that has the potential to stimulate tissue healing, indicating
useful for preventing and treating intestine inflammation.
Abstract
We
studied a polyphenol-enriched cocoa extract (PCE) with epicatechin, procyanidin
B2, catechin, and procyanidin B1 as the major phenolics for its
anti-inflammatory properties against dextran sulfate sodium (DSS)-induced
ulcerative colitis (UC) in mice. PCE reduced colon damage, with
significant reductions in both the extent and the severity of the inflammation
as well as in crypt damage and leukocyte infiltration in the mucosa. Analysis
ex vivo showed clear decreases in the production of nitric oxide,
cyclooxygenase-2, pSTAT-3, and pSTAT1α, with NF-κB p65 production being
slightly reduced. Moreover, NF-κB activation was reduced in RAW 264.7 cells in
vitro. In conclusion, the
inhibitory effect of PCE on acute UC induced by DSS in mice was attenuated by
oral administration of PCE obtained from cocoa. This effect is principally due
to the inhibition of transcription factors STAT1 and STAT3 in intestinal cells,
with NF-κB inhibition also being implicated.
Here is an excellent paper on oxidative stress. It is about COPD, but applicable to any condition in which oxidative stress is present.
The following paper would suggest that people with COPD would benefit
from epicatechin.
The cocoa flavanol (-)-epicatechin protects the cortisol response.
Abstract
Various health benefits of the cocoa
flavanol (-)-epicatechin (EC) have been attributed to its antioxidant and
anti-inflammatory potency. In
the present study we investigated whether EC is able to prevent deterioration
of the anti-inflammatory effect of the glucocorticoid (GC) cortisol in the
presence of oxidative stress. It was found that cortisol reduces
inflammation in differentiated monocytes. Oxidative stress extinguishes the anti-inflammatory effect
of cortisol, leading to cortisol resistance. EC reduces intracellular
oxidative stress as well as the development of cortisol resistance. This
further deciphers the enigmatic mechanism of EC by which it exerts its
anti-inflammatory and antioxidant action. The observed effect of the cocoa flavanol EC will
especially be of relevance in pathophysiological conditions with increased
oxidative stress and consequential GC resistance and provides a fundament for
the rational use of dietary antioxidants.
Conclusion
It would seem that in someone with autism epicatechin is worth a try,
other indicators might well include:-
·
Low MOCOS
·
Low ferritin
·
Oxidative stress
And even
·
Restless leg
syndrome (symptom of low ferritin)
·
Poor sleep
patterns (symptom of low ferritin)
Boosting anti-oxidant enzymes (via gene expression) may be a useful
add-on therapy to anti-oxidants themselves.
This is likely true for COPD and autism/schizophrenia.
If you are wondering whether there is anemia or iron deficiency in
autism, your questions are likely answered here:-
This research considers the prevalence of iron deficiency in children
with autism and Asperger syndrome and examines whether this will influence
guidelines and treatment. Retrospective analysis of the full blood count and,
as far as available, serum ferritin measurements of 96 children (52 with autism
and 44 with Asperger syndrome) was undertaken. Six of the autistic group were
shown to have iron deficiency anaemia and, of the 23 autistic children who had serum ferritin
measured, 12 were iron deficient. Only two of the Asperger group had
iron deficiency anaemia and, of the 22 children who had their serum ferritin
measured, only three were iron deficient. Iron deficiency, with or without anaemia, can impair
cognition and affect and is associated with developmental slowing in
infants and mood changes and poor concentration in children. This study showed a very high
prevalence of iron deficiency in children with autism, which could potentially
compromise further their communication and behavioural impairments.
As we saw with biotin and soon will with vitamin
B12, it seems that people with autism can have unexpected deficiencies of key
substances even though their diet may not be deficient. The identified iron deficiency is an iron
storage deficiency. With biotin the body was unable
to recycle the vitamin biotin, due to a problem with the enzyme biotinidase,
hence there was a deficiency.
Correcting these deficiencies is quite simple and may well improve any related autism symptoms. In people without these dysfunctions/deficiencies any such supplements would yield no benefit and might even produce side effects.
