UA-45667900-1

Monday, 2 November 2015

Brain Hypoperfusion in Autism & Cocoa



Today’s post is simpler than many earlier ones and is actionable.

A known feature of many neurological conditions like Alzheimer’s and dementia is reduced blood flow to certain parts of the brain.  In the medical jargon this is called hypoperfusion.

This reduced blood flow is also present in autism and is measurable by MRI.

We encountered epicatechin in early posts on cocoa flavanols.  It would seem that one of epicatechin’s many effects is to increase cerebral blood flow. 

Two chocolate companies, Mars (Cocoavia) in the US and Barry Callebaut (ACTICOA) in France, have developed high flavanol cocoa.  10 g of their cocoa contains about 1 g of flavanols and produces cognitive benefits; even a quarter of this dose gives the cardiovascular benefits.  Mars, in particular, are funding a great deal of research and have committed to a five year project with Harvard.  The high flavanol products are available today.


Brain Perfusion Anomalies in Autism

While most research focuses on Alzheimer’s and other types of cognitive impairment and memory loss, there are studies on brain perfusion in autism.



  
Autism is a severe developmental disorder, the biological mechanisms of which remain unknown. Hence we conducted this study to assess the cerebral perfusion in 10 children with autism and mental retardation. Five age matched normal children served as controls. These cases were evaluated by single photon emission computed tomography (SPECT) using Tc-99m HMPAO, followed by segmental quantitative evaluation. Generalized hypoperfusion of brain was observed in all 10 cases as compared to controls. Frontal and prefrontal regions revealed maximum hypoperfusion. Subcortical areas also indicated hypoperfusion. We conclude that children with autism have varying levels of perfusion abnormities in brain causing neurophysiologic dysfunction that presents with cognitive and neuropsychological defects.
  
Significant hypoperfusion was observed at cortical and subcortical areas of brain in autistic subjects, suggesting that the structural abnormalities
of these brain areas may result in reduced cortical activity, thus causing dysfunction of these brain areas, and eventually producing some of the
emotional and behavioral disorders usually described in autistic subjects. These SPECT findings may help to explain several behavioral features of autism, such as impulsive and aggressive behaviours (to self and others), motor disinhibition (such as stereotypic and manneristic movements and echophenomena), and deficits in planning, sequencing and attention.


Abnormal regional cerebral blood flow in childhood autism


Neuroimaging studies of autism have shown abnormalities in the limbic system and cerebellar circuits and additional sites. These findings are not, however, specific or consistent enough to build up a coherent theory of the origin and nature of the brain abnormality in autistic patients. Twenty-three children with infantile autism and 26 non-autistic controls matched for IQ and age were examined using brain-perfusion single photon emission computed tomography with technetium-99m ethyl cysteinate dimer. In autistic subjects, we assessed the relationship between regional cerebral blood flow (rCBF) and symptom profiles. Images were anatomically normalized, and voxel-by-voxel analyses were performed. Decreases in rCBF in autistic patients compared with the control group were identified in the bilateral insula, superior temporal gyri and left prefrontal cortices. Analysis of the correlations between syndrome scores and rCBF revealed that each syndrome was associated with a specific pattern of perfusion in the limbic system and the medial prefrontal cortex. The results confirmed the associations of (i) impairments in communication and social interaction that are thought to be related to deficits in the theory of mind (ToM) with altered perfusion in the medial prefrontal cortex and anterior cingulate gyrus, and (ii) the obsessive desire for sameness with altered perfusion in the right medial temporal lobe. The perfusion abnormalities seem to be related to the cognitive dysfunction observed in autism, such as deficits in ToM, abnormal responses to sensory stimuli, and the obsessive desire for sameness. The perfusion patterns suggest possible locations of abnormalities of brain function underlying abnormal behaviour patterns in autistic individuals.


Cerebral Hypoperfusion and HBOT?

One therapy proposed to treat Cerebral Hypoperfusion in autism is hyperbaric oxygen therapy (HBOT).  Some proponents go as far as to link specific areas of the brain to specific autistic features as below.







The mainstream view, among those using HBOT for other conditions, is that it would not help stimulate increased blood flow in autistic brains.  But there are proponents of the therapy like Rossignol.




You may have realized that the science exists to test, once and for all, whether HBOT can improve cerebral blood flow in autism.  It just takes two visits to an MRI.




I did see a report about a US neurologist who showed via MRI that the cerebral blood flow of his autistic patient improved using HBOT and he tried to use this to get access to the further HBOT on insurance.



Hypoperfusion in Alzheimer’s, Dementia  and Cognitive Impairment

Reduced cerebral blood flow is a marker of incipient dementia.  I expect one day this might even be used to trigger preventative therapy.

Cerebral hypoperfusion and clinical onset of dementia: the Rotterdam Study.

Abstract

Cerebral blood flow (CBF) velocity is decreased in patients with Alzheimer's disease. It is being debated whether this reflects diminished demand because of advanced neurodegeneration or that cerebral hypoperfusion contributes to dementia. We examined the relation of CBF velocity as measured with transcranial Doppler with dementia and markers of incipient dementia (ie, cognitive decline and hippocampal and amygdalar atrophy on magnetic resonance imaging) in 1,730 participants of the Rotterdam Study aged 55 years and older. Cognitive decline in the 6.5 years preceding CBF velocity measurement was assessed with repeated Mini-Mental State Examinations in nondemented subjects (n = 1,716). Hippocampal and amygdalar volumes were assessed in a subset of 170 nondemented subjects. Subjects with greater CBF velocity were less likely to have dementia. Furthermore, in nondemented subjects, greater CBF velocity was related to significantly less cognitive decline over the preceding period (odds ratio per standard deviation increase in mean CBF 0.74 [95% confidence interval, 0.58-0.98]) and larger hippocampal and amygdalar volumes. A low CBF is associated with dementia, but also with markers of incipient dementia. Although we cannot exclude that this is caused by preclinical neurodegeneration leading to hypoperfusion, it does suggest that cerebral hypoperfusion precedes and possibly contributes to onset of clinical dementia.


Vascular dementia

Vascular dementia is the second-most-common form of dementia after Alzheimer's disease.  It is a much simpler condition, it is dementia caused by problems in the supply of blood to the brain, typically by a series of minor strokes.

The incidence peaks between the fourth and the seventh decades of life and 80% will have a history of hypertension. Patients develop progressive cognitive, motor and behavioural signs and symptoms.

Blood pressure rises with aging and the risk of becoming hypertensive in later life is considerable

It would seem that you could treat hypertension and vascular dementia with the same preventative therapy.  See the clinical trial on treating vascular aging with Cocoa, later in this post.






It has also been suggested that endothelial dysfunction and vascular inflammation may also contribute to increased peripheral resistance and vascular damage in hypertension. 

In essence you want to control peripheral resistance and before it is too late.  It really is a case of “a stitch in time saves nine”.

The research done in to peripheral resistance / vascular stiffness can be re-purposed to help us treat brain hypoperfusion.  In autism we may have Brain Hypoperfusion, but without high blood pressure (hypertension).




Increased vascular stiffness, endothelial dysfunction, and isolated systolic hypertension are hallmarks of vascular aging. Regular cocoa flavanol (CF) intake can improve vascular function in healthy young and elderly at-risk individuals. However, the mechanisms underlying CF bioactivity remain largely unknown. We investigated the effects of CF intake on cardiovascular function in healthy young and elderly individuals without history, signs, or symptoms of cardiovascular disease by applying particular focus on functional endpoints relevant to cardiovascular aging. In a randomized, controlled, double-masked, parallel-group dietary intervention trial, 22 young (<35 years) and 20 elderly (5080 year) healthy, male non-smokers consumed either a CF-containing drink (450 mg CF) or nutrientmatched, CF-free control drink bi-daily for 14 days.
The primary endpoint was endothelial function as measured by flow-mediated vasodilation (FMD). Secondary endpoints included cardiac output, vascular
stiffness, conductance of conduit and resistance arteries, and perfusion in the microcirculation. Following 2 weeks of CF intake, FMD improved in young (6.1±0.7 vs. 7.6±0.7 %, p<0.001) and elderly (4.9 ± 0.6 vs. 6.3 ± 0.9 %, p < 0.001).
Secondary outcomes demonstrated in both groups that CF intake decreased pulse wave velocity and lowered total peripheral resistance, and increased arteriolar and microvascular vasodilator capacity, red cell deformability, and diastolic blood pressure, while cardiac output remained affected. In the elderly, baseline systolic blood pressure was elevated, driven by an arterial-stiffness-related augmentation.
CF intake decreased aortic augmentation index (9 %) and thus systolic blood pressure (7 mmHg;



Cocoa Flavanols

I did write an earlier post about the various benefits of Cocoa Flavanols. 


  
Here is a very good review paper:-



Norman Hollenberg, at Harvard, has been an advocate of high flavanol cocoa for decades.  Here is one of his papers.





Using functional MRI, the following study measures the effect on brain blood flow, before and after taking a high flavanol cooca drink









There is now good evidence that the acute benefits for cognitive function and blood flow exerted by cocoa flavanol consumption peak approximately 90120 min postconsumption (Schroeter et al. 2006; Francis et al. 2006; Scholey et al. 2010; Field et al. 2011); however, it is presently unclear whether separate chronic mechanisms exists following cumulative consumption over several weeks and months, or indeed whether chronic consumption enhances the effectiveness of acute mechanisms in a cumulative fashion. Despite several plausible mechanisms for increased neuronal activity (as described above), it remains to be seen whether a single cocoa flavanol dose-induced increase in CBF is associated with concomitant benefits in cognitive performance in the immediate postprandial period. More broadly, recent reviews of acute interventions and epidemiological surveys provide good evidence that flavonoids and their subclasses are beneficial for cognitive function


In conclusion, the present findings support the hypothesis that flavanol-rich cocoa beverages are associated with increased CBF within a 2-h post-prandial time frame. More specifically, increased brain perfusion following the HF drink relative to the LF drink was observed in the anterior cingulate cortex and a region in the left parietal lobe. These data add to the substantial body of literature demonstrating that flavanol consumption is beneficial for peripheral and cerebral vascular function and thus for maintaining, protecting and enhancing cardiovascular health.



Does High Flavanol Cocoa have an effect in Autism?

This is probably the question you have been asking yourself.

I did acquire some ACTICOA, high flavanol cocoa some time ago.  I was wondering how I was going to administer enough of it to make a trial.  In the trials on improving memory in older adults 10g a day was needed.

While adding it to milk seems an obvious choice, Hollenberg suggests that the milk may neutralize the flavanols.  This is true with black tea; once you add milk you lose its healthy antioxidant properties.

In the end I choose to add 5ml to the breakfast broccoli powder and water concoction and mix with a frappe mixer.  Monty, aged 12 with ASD, was the ever willing test subject.

Two and a half hours later there was unprompted laughter and smiling.  This is repeated each time I give the ACTICOA  cocoa.

According to the literature, the peak level of epicatechin occurs 2 to 3 hours after consuming cocoa.

Then I tried a regular raw cocoa powder at the same dose; no laughter.

So I conclude that ACTICOA is indeed different to regular non-alkalized cocoa powder.  The more common alkalized cocoa has virtually no flavanols at all, and this is what is used to make most chocolate and is sold in supermarkets as "cocoa".

There are potentially other sources of epicatechin, but you really want a reliable standardized product.  If you live in the US/Canada this is easy; you can buy the Cocoavia product from Mars.  It is not cheap if you want 1g of flavanols a day.


The literature does suggest that there is a cumulative effect of taking epicatechin and Hollenberg has documented that regular consumption of unprocessed cocoa (rich in flavanols) is associated with numerous health benefits, particularly related to blood flow (strokes, heart attacks, endothelial dysfunction, cholesterol etc.)

Since Mars are now funding considerable research into the health benefits of these flavanols, I did think of suggesting they look at autism.

They could take a group of people with autism, measure their IQ and then score their autism using one of the standard scales.  Then off to the MRI to measure blood flow and velocity in different parts of the brain.

Give half of the test subjects a daily high flavanol drink and the other half a low flavanol drink.  After three months, repeat the IQ test, autism test and measure blood flow again via MRI.

I suspect that reduced blood flow/hypoperfusion would be more present in those with lower IQ and that they might show improved IQ at the end of the trial.  I suspect that in terms of autism, most would show an improvement on the high flavanol treatment.

I would like to think that after three months, blood flow/velocity would have increased.

You could then repeat on people with Down Syndrome and more general MR/ID.








Wednesday, 21 October 2015

Biomarkers in Autism






This post has been sitting unfinished for a while, so I decided to publish it before I forget all about it

The two papers discussed today really confirm much of what we have already established in this blog, but they are very useful as a recap and for those with limited time.

The first paper is extremely comprehensive and, if you go through it very slowly, really tells you much of what you need to know about the biology of autism.  It is some wonder that so few clinicians are aware of these findings.



Abstract

Autism spectrum disorders (ASDs) are complex, heterogeneous disorders caused by an interaction between genetic vulnerability and environmental factors. In an effort to better target the underlying roots of ASD for diagnosis and treatment, efforts to identify reliable biomarkers in genetics, neuroimaging, gene expression, and measures of the body’s metabolism are growing. For this article, we review the published studies of potential biomarkers in autism and conclude that while there is increasing promise of finding biomarkers that can help us target treatment, there are none with enough evidence to support routine clinical use unless medical illness is suspected. Promising biomarkers include those for mitochondrial function, oxidative stress, and immune function. Genetic clusters are also suggesting the potential for useful biomarkers.



Here are the key parts; I do suggest you read the full text of the paper.


Metabolic Biomarkers


There are no autism-defining, metabolic biomarkers, but examining the biomarkers of pathways associated with ASD can point to potentially treatable metabolic abnormalities and provide a baseline that can be tracked over time. Each child may have different metabolic pathologies related to SNPs, nutrient deficiencies, and toxic exposures. Examples of metabolic disorders that can lead to an autistic-like presentation include phenylketonuria (PKU) (37), disorders of purine metabolism (38), biotinidase deficiency (39), cerebral folate deficiency (40), creatine deficiency (41), and excess propionic acid (which is produced by Clostridium) (42, 43).

A recent review assessed the research on physiological abnormalities associated with ASD (44). The authors identified four main mechanisms that have been increasingly studied during the past decade: immunologic/inflammation, oxidative stress, environmental toxicants, and mitochondrial abnormalities. In addition, there is accumulating research on the lipid, GI systems, microglial activation, and the microbiome, and how these can also contribute to generating biomarkers associated with ASD.

The brain is highly vulnerable to oxidative stress (51), particularly in children (52) during the early part of development (47). As environmental events and metabolic imbalances affect oxidative stress and methylation, they also can affect the expression of genes.

Several studies have detected altered levels of a large collection of substances in body-based fluids from ASD subjects compared to controls (e.g., serum, whole-blood, and CSF) (53). These findings encompass either of two main disease-provoking mechanisms: a CNS disorder that is being detected peripherally [e.g., serotonin and its metabolites, sulfate (54), low platelet levels of gamma-aminobutyric acid (GABA) (55), low oxytocin (which affects social affiliation) (56), and low vitamin D levels (57, 58)] or a systemic abnormality that has repercussions in the brain (59).

Oxidative stress markers

Oxidative stress can be detected by studying antioxidant status, antioxidant enzymes, lipid peroxidation, and protein/DNA oxidation, all of which have been found to be elevated in children with autism (Table (Table2).2). Different subgroups of children with ASD have different redox abnormalities, which may arise from various sources



Measurements of antioxidant status include measurement of glutathione, the primary antioxidant in the protection against oxidative stress, neuroinflammation, and mitochondrial damage (68, 69). Glutathione is instrumental in regulating detoxification pathways and modulates the production of precursors to advanced glycation end products (AGEs) (70). Measuring reduced glutathione, oxidized glutathione, or the ratio of reduced glutathione to oxidized glutathione helps determine the patient’s oxidation status. In many patients with ASD, the ratio of reduced glutathione to oxidized glutathione is decreased, indicating a poor oxidation status

The enzyme glutathione peroxidase has been used as a marker and is typically reduced. There are mixed results concerning the enzyme levels of superoxide dismutase (SOD) (72). Other markers for glutathione inadequacy include alpha hydroxybutyrate, pyroglutamate, and sulfate, which can be assessed in an organic acid test. Lipid peroxidation refers to the oxidative degradation of cell membranes. There is a significant correlation between the severity autism and urinary lipid peroxidation products (67), which are increased in patients with ASD

Plasma F2t-Isoprostanes (F2-IsoPs) are the most sensitive indicator of redox dysfunction and are considered by some to be the gold standard measure of oxidative stress (73). They are increased in patients with ASD and are even higher when accompanied by gastrointestinal dysfunction (73).

Decreased levels of major antioxidant serum proteins transferrin (iron-binding protein) and ceruloplasmin (copper binding protein) have been observed in patients with ASD. The levels of reduction in these proteins correlate with loss of previously acquired language (47) although there are mixed reviews of the significance of this (66).


Plasma 3-chlortyrosine (3CT), a measure of reactive nitrogen species and myeloperoxidase activity, is an established biomarker of chronic inflammatory response. Plasma 3CT levels reportedly increased with age for those with ASD and mitochondrial dysfunction but not for those with ASD without mitochondrial dysfunction (65).

3-Nitrotyrosine (3NT) is a plasma measure of chronic immune activation and is a biomarker of oxidative protein damage and neuron death. This measure correlates with several measures of cognitive function, development, and behavior for subjects with ASD and mitochondrial dysfunction but not for subjects with ASD without a mitochondrial dysfunction (65).


Mitochondrial dysfunction markers

Mitochondrial dysfunction is marked by impaired energy production. Some children with ASD are reported to have a spectrum of mitochondrial dysfunction of differing severity (44) (Table (Table3).3). Mitochondrial dysfunction, most likely an early event in neurodegeneration (76), is one of the more common dysfunctions found in autism (77) and is more common than in typical controls (78). There is no reliable biomarker to identify all cases of mitochondrial dysfunction (79). It is possible that up to 80% of the mitochondrial dysfunction in patients with both ASD and a mitochondrial disorder are acquired rather than inherited (44).

Mitochondrial dysfunction can be a downstream consequence of many proposed factors including dysreactive immunity and altered calcium (Ca2+) signaling (80), increased nitric oxide and peroxynitrite (68), propionyl CoA (81), malnutrition (82), vitamin B6 or iron deficiencies (83), toxic metals (83), elevated nitric acid (84, 85), oxidative stress (86), exposure to environmental toxicants, such as heavy metals (8789), chemicals (90), polychlorinated biphenyls (PCBs) (91), pesticides (92, 93), persistent organic pollutants (POPs) (94), and radiofrequency radiation (95). Other sources of mitochondrial distress include medications such as valproic acid (VPA), which inhibits oxidative phosphorylation (96) and neuroleptics (97, 98).

Markers of mitochondrial dysfunction include lactate, pyruvate and lactate-to-pyruvate ratio, carnitine (free and total), quantitative plasma amino acids, ubiquinone, ammonia, CD, AST, ALT, CO2 glucose, and creatine kinase (CK) (44). Many studies of ASD report elevations in lactate and pyruvate, others report a decrease in carnitine, while others report abnormal alanine in ASD patients (44) or elevations in aspartate aminotransferase and serum CK (99). Increases in lactate are not specific and may only occur during illness, after exercise or struggling during a blood draw (100).


Rossignol and Frye (44) recommend a mitochondrial function screening algorithm. This includes fasting morning labs of lactate, pyruvate, carnitine (free and total), acyl carnitine panel, quantitative plasma amino acids, ubiquinone, ammonia, CK, AST/ALT, CO2, and glucose (44). The interpretation of such a panel and the indications for specific treatments has not yet been established.

Methylation

The methylation pathway provides methyl groups for many functions, including the methylation of genes, which can result in the epigenetic changes of turning genes on and off (Table (Table4).4). This transfer occurs when S-adenosylmethionine (SAM) donates a methyl group and is transformed to S-adenosylhomocysteine (SAH). SAH can be transferred to homocysteine, which can either be re-methylated to methionine or be transferred by the sulfuration pathway to cysteine to create glutathione. With increased oxidative stress, SAH might be diverted away from the methylation pathway to the sulfuration pathway in order to make more glutathione. This will result in less methionine and less methylation ability.

A marker of methylation dysfunction is decreased SAM/SAH ratio in patients with ASD. Fasting plasma methionine decreases since through SAM it is the main methyl donor. Fasting plasma cysteine, a sulfur containing amino acid is the rate-limiting step in the production of glutathione and is significantly decreased. Plasma sulfate is decreased, which may impair detoxification pathways. Homocysteine is generally increased, but the studies are mixed (66). Vitamin B12 and folate are required for the methylation pathway. The MTHFR genetic SNP is reported to heavily influence the methylation pathway (66).

Immune dysregulation


Cytokine evaluation


Chronic inflammation and microglia cell activation is present in autopsied brains of people with ASD (101, 102) (Table (Table5).5). Factors that increase the risk of activating brain microglia include traumatic brain injury (TBI) (103) reactive oxygen species (104) and a dysfunctional blood brain barrier (105). The blood brain barrier can be compromised by oxidative stress (106), acutely stressful situations (107), elevated homocysteine (108), diabetes (109), and hyperglycemia (110). Cytokines can pass through a permeable blood brain barrier and start this process (111). Hence, cytokines can serve as a marker of the immune dysregulation, which can further complicate ASD.


Autoimmunity and maternal antibodies


Autoimmune autistic disorder is proposed as a major subset of autism (118), and autoimmunity may play a role in the pathogenesis of language and social developmental abnormalities in a subset of children with these disorders (119). There are many autoantibodies found in the nervous system of children with ASD who have a high level of brain antibodies (120, 121). These can be measured as biomarkers in this subset of ASD patients. The anti ganglioside M1 antibodies (122), antineuronal antibodies (123), and serum anti-nuclear antibodies (123, 124) correlate with the severity of autism. Other autoantibodies postulated to play a pathological role in autism include: anti neuron-axon filament protein (anti-NAFP) and glial fibrillary acidic protein (anti-GFAP) (125), antibodies to brain endothelial cells and nuclei (119), antibodies against myelin basic protein (126, 127), and anti myelin associated glycoprotein, an index for autoimmunity in the brain (128). BDNF antibodies were found higher in ASD (129), and low BDNF levels may be involved in the pathophysiology of ASD (130).

Antibodies in patients with autism are found to cells in the caudate nucleus (131), cerebellum (132, 133), hypothalamus and thalamus (121), the cingulate gyrus (134), and to cerebral folate receptors (135). Children with cerebellar autoantibodies had lower adaptive and cognitive function as well as increased aberrant behaviors compared to children without these antibodies (132).

Mother’s immune status


Research studies indicate an association between viral or bacterial infections in expectant mothers and their ASD offspring (136, 137). Maternal antibodies cross the underdeveloped blood brain barrier of the fetus (138) leading to impaired fetal neurodevelopment and long-term neurodegeneration, neurobehavioral, and cognitive difficulties (139).

Dysbiosis


When the gut becomes inflamed, it breaks down and becomes permeable, sometimes referred to as dysbiosis. Dysbiosis is reported to be an upstream contributing factor to autoimmune conditions and inflammation. Markers under consideration include circulating antibodies against tight junction proteins, LPS, actomyosin (145) calprotectin (146), and lactoferrin (147). Dysbiosis was found in 25.6% of patients with ASD (148). It is proposed to have a direct effect on the brain as it is a hypothesized source of inflammation (149151) and autoimmunity (152, 153), possibly through molecular mimicry (154). Diet is one source of dysbiosis (155).


Amino acids and neuropeptides


Platelet hyperserotonemia is considered one of the most consistent neuromodulator findings in patients with ASD (Table (Table6).6). As for other neuropeptides, a recent review reported approximately 15 components that are altered in ASD compared to controls (53). Among them, interesting research has been done on glutamate, GABA, BDNF, and dopamine and noradrenaline systems. A recent study reported a positive correlation between severity of clinical symptoms and plasma GABA levels in patients with ASD, supporting the idea of a disrupted GABAergic system (156).

 

Fatty acid analysis


Abnormal fatty acid metabolism may play a role in the pathogenesis of ASD and may suggest some metabolic or dietary abnormalities in the regressive form of autism (42, 157). There is evidence of a relationship between changes in brain lipid profiles and the occurrence of ASD-like behaviors using a rodent model of autism (42). Hyperactivity in patients was inversely related to the fluidity of the erythrocyte membrane and membrane polyunsaturated fatty acid (PUFA) levels (158). Imbalances of membrane fatty acid composition and PUFA loss can affect ion channels and opiate, adrenergic, insulin receptors (159) and the modulation of (Na + K)-ATPase activity (160). Analysis of red blood cell membrane fatty acids is a very sensitive indicator of tissue status and may reflect the brain fatty acid composition (161).
Seventeen percent of children with ASD manifest biomarkers of abnormal mitochondrial fatty acid metabolism, the majority of which are not accounted for by genetic mechanisms (162). Patients with ASD had reduced percentages of highly unsaturated fatty acids (163) and an increase in ω6/ω3 ratio (158).

Biomedical Interventions


There are no published studies of interventions for ASD that use neuroimaging or genetic biomarkers in a prospective manner to guide treatment. Biomedical interventions based on body fluid/product biomarkers have been used in a small but growing numbers of well designed, published studies. Several recent reviews summarize these.

+ + +



If you have managed to digest all of that information, here is another very interesting paper.

The researchers are, as so often, from Johns Hopkins.  This time they propose an idea to simplify the understanding of the bewildering number of autism sub-types.

I have frequently commented in this blog that in many identified underlying dysfunctions, being hyper (too much) or hypo (two little) causes the same effect, i.e. autism.

They split autism into:-

·        hyper-active pro-growth signaling pathways (e.g. big heads)
·        hypo-active pro-growth signaling pathways  (e.g. small heads)


So the first question is whether the patient is type A or type B.









It is definitely a step forward in simplifying what is going on, so that one day a clinician, without being a Nobel Laureate, could treat autism without just using trial and error.  If the clinician had also read, and understood, the first paper, he/she really would be able to help the patient.






The genetic and phenotypic heterogeneity of autism spectrum disorders (ASD) presents a substantial challenge for diagnosis, classification, research, and treatment. Investigations into the underlying molecular etiology of ASD have often yielded mixed and at times opposing findings. Defining the molecular and biochemical underpinnings of heterogeneity in ASD is crucial to our understanding of the pathophysiological development of the disorder, and has the potential to assist in diagnosis and the rational design of clinical trials. In this review, we propose that genetically diverse forms of ASD may be usefully parsed into entities resulting from converse patterns of growth regulation at the molecular level, which lead to the correlates of general synaptic and neural overgrowth or undergrowth. Abnormal brain growth during development is a characteristic feature that has been observed both in children with autism and in mouse models of autism. We review evidence from syndromic and non-syndromic ASD to suggest that entities currently classified as autism may fundamentally differ by underlying pro- or anti-growth abnormalities in key biochemical pathways, giving rise to either excessive or reduced synaptic connectivity in affected brain regions. We posit that this classification strategy has the potential not only to aid research efforts, but also to ultimately facilitate early diagnosis and direct appropriate therapeutic interventions.