A potential pathogenic role of oxalate in autism

Abnormal Porphyrin Metabolism in Autism Spectrum Disorder and Therapeutic Implications

Autism spectrum disorder (ASD) is a mosaic of neurodevelopmental conditions composed of early-onset social interaction and communication deficits, along with repetitive and/or restricted patterns of activities, behavior, and interests. ASD affects around 1% of children worldwide, with a male predominance. Energy, porphyrin, and neurotransmitter homeostasis are the key metabolic pathways affected by heavy metal exposure, potentially implicated in the pathogenesis of ASD. Exposure to heavy metals can lead to an altered porphyrin metabolism due to enzyme inhibition by heavy metals. Heavy metal exposure, inborn genetic susceptibility, and abnormal thiol and selenol metabolism may play a significant role in the urinary porphyrin profile anomalies observed in ASD. Altered porphyrin metabolism in ASD may also be associated with, vitamin B6 deficiency, hyperoxalemia, hyperhomocysteinemia, and hypomagnesemia. The present review considers the abnormal porphyrin metabolism in ASD in relation to the potential pathogenic mechanism and discusses the possible metabolic therapies such as vitamins, minerals, cofactors, and antioxidants that need to be explored in future research. Such targeted therapeutic therapies would bring about favorable outcomes such as improvements in core and co-occurring symptoms.

Multi-site microbiota alteration is a hallmark of kidney stone formation

BACKGROUND

Inquiry of microbiota involvement in kidney stone disease (KSD) has largely focussed on potential oxalate handling abilities by gut bacteria and the increased association with antibiotic exposure. By systematically comparing the gut, urinary, and oral microbiota of 83 stone formers (SF) and 30 healthy controls (HC), we provide a unified assessment of the bacterial contribution to KSD.

RESULTS

Amplicon and shotgun metagenomic sequencing approaches were consistent in identifying multi-site microbiota disturbances in SF relative to HC. Biomarker taxa, reduced taxonomic and functional diversity, functional replacement of core bioenergetic pathways with virulence-associated gene markers, and community network collapse defined SF, but differences between cohorts did not extend to oxalate metabolism.

CONCLUSIONS

We conclude that multi-site microbiota alteration is a hallmark of SF, and KSD treatment should consider microbial functional restoration and the avoidance of aberrant modulators such as poor diet and antibiotics where applicable to prevent stone recurrence. Video Abstract.

Ratings of the Effectiveness of 13 Therapeutic Diets for Autism Spectrum Disorder: Results of a National Survey

This study presents the results of the effectiveness of 13 therapeutic diets for autism spectrum disorder from 818 participants of a national survey, including benefits, adverse effects, and symptom improvements. The average Overall Benefit of diets was 2.36 (0 = no benefit, 4 = great benefit), which was substantially higher than for nutraceuticals (1.59/4.0) and psychiatric/seizure medications (1.39/4.0), p < 0.001. The average Overall Adverse Effects of diets was significantly lower than psychiatric/seizure medications (0.10 vs. 0.93, p < 0.001) and similar to nutraceuticals (0.16). Autism severity decreased slightly over time in participants who used diet vs. increasing slightly in those that did not (p < 0.001). Healthy and Feingold diets were the two top-rated diets by Overall Benefit; the ketogenic diet was the highest for nine symptoms (though had fewer respondents); and the gluten-free/casein-free diet was among the top for overall symptom improvements. Different diets were reported to affect different symptoms, suggesting that an individual's symptoms could be used to guide which diet(s) may be the most effective. The results suggest that therapeutic diets can be safe and effective interventions for improving some ASD-related symptoms with few adverse effects. We recommend therapeutic diets that include healthy foods and exclude problematic foods. Therapeutic diets are inexpensive treatments that we recommend for consideration by most people with ASD.

Oxalate Homeostasis in Non-Stone-Forming Chronic Kidney Disease: A Review of Key Findings and Perspectives

Chronic kidney disease (CKD) is a significant global public health concern associated with high morbidity and mortality rates. The maintenance of oxalate homeostasis plays a critical role in preserving kidney health, particularly in the context of CKD. Although the relationship between oxalate and kidney stone formation has been extensively investigated, our understanding of oxalate homeostasis in non-stone-forming CKD remains limited. This review aims to present an updated analysis of the existing literature, focusing on the intricate mechanisms involved in oxalate homeostasis in patients with CKD. Furthermore, it explores the key factors that influence oxalate accumulation and discusses the potential role of oxalate in CKD progression and prognosis. The review also emphasizes the significance of the gut-kidney axis in CKD oxalate homeostasis and provides an overview of current therapeutic strategies, as well as potential future approaches. By consolidating important findings and perspectives, this review offers a comprehensive understanding of the present knowledge in this field and identifies promising avenues for further research.

Glycoproteomics meets thermodynamics: A calorimetric study of the effect of sialylation and synergistic anion on the binding of iron to human serum transferrin

The thermodynamic parameters for the binding of ferric ions to human serum transferrin (hTf) as the major mediator of iron transport in blood plasma were determined by isothermal titration calorimetry in the presence of carbonate and oxalate as synergistic anions at pH 7.4. The results indicate that the binding of ferric ions to the two binding sites of hTf is driven both enthalpically and entropically in a lobe-dependent manner: binding to the C-site is mainly enthalpically driven, whereas binding to the N-site is mainly entropically driven. Lower sialic acid content of hTf leads to more exothermic apparent binding enthalpies for both lobes, while the increased apparent binding constants for both sites were found in the presence of carbonate. Sialylation also unequally affected the heat change rates for both sites only in the presence of carbonate, but not in the presence of oxalate. Overall, the results suggest that the desialylated hTf has a higher iron sequestering ability, which may have implications for iron metabolism.

The Rationale for Vitamin, Mineral, and Cofactor Treatment in the Precision Medical Care of Autism Spectrum Disorder

Children with autism spectrum disorder may exhibit nutritional deficiencies due to reduced intake, genetic variants, autoantibodies interfering with vitamin transport, and the accumulation of toxic compounds that consume vitamins. Importantly, vitamins and metal ions are essential for several metabolic pathways and for neurotransmitter functioning. The therapeutic benefits of supplementing vitamins, minerals (Zinc, Magnesium, Molybdenum, and Selenium), and other cofactors (coenzyme Q10, alpha-lipoic acid, and tetrahydrobiopterin) are mediated through their cofactor as well as non-cofactor functions. Interestingly, some vitamins can be safely administered at levels far above the dose typically used to correct the deficiency and exert effects beyond their functional role as enzyme cofactors. Moreover, the interrelationships between these nutrients can be leveraged to obtain synergistic effects using combinations. The present review discusses the current evidence for using vitamins, minerals, and cofactors in autism spectrum disorder, the rationale behind their use, and the prospects for future use.

Substitution of carbonate by non-physiological synergistic anion modulates the stability and iron release kinetics of serum transferrin

Serum transferrin (sTf) is a bi-lobal protein. Each lobe of sTf binds one Fe³⁺ ion in the presence of a synergistic anion. Physiologically, carbonate is the main synergistic anion but other anions such as oxalate, malonate, glycolate, maleate, glycine, etc. can substitute for carbonate in vitro. The present work provides the possible pathways by which the substitution of carbonate with oxalate affects the structural, kinetic, thermodynamic, and functional properties of blood plasma sTf. Analysis of equilibrium experiments measuring iron release and structural unfolding of carbonate and oxalate bound diferric-sTf (Fe₂sTf) as a function of pH, urea concentration, and temperature reveal that the structural and iron-centers stability of Fe₂sTf increase by substitution of carbonate with oxalate. Analysis of isothermal titration calorimetry (ITC) scans showed that the affinity of Fe³⁺ with apo-sTf is enhanced by substituting carbonate with oxalate. Analysis of kinetic and thermodynamic parameters measured for the iron release from the carbonate and oxalate bound monoferric-N-lobe of sTf (Fe_NsTf) and Fe₂sTf at pH 7.4 and pH 5.6 reveals that the substitution of carbonate with oxalate inhibits/retards the iron release via increasing the enthalpic barriers.

TF and TCF4 gene polymorphisms are linked to autism spectrum disorder: a case-control study

OBJECTIVE

Although the prevalence of autism spectrum disorder (ASD) is increasing, appropriate diagnosis and prevention strategies are still lacking. This case-control study was designed to explore the association between ASD and the rs1867503 and rs9951150 polymorphisms of the TF and TCF4 genes, respectively.

METHODS

Ninety-six children with ASD and 118 healthy children were recruited and polymerase chain reaction-restriction fragment length polymorphism technique was applied for genotyping.

RESULTS

The frequencies of the mutant allele G were 48% and 44% for the rs1867503 and rs9951150 polymorphisms, respectively. In our analysis, both TF and TCF4 polymorphisms were associated with an increased risk of developing ASD. AG heterozygotes (OR = 3.18), GG mutant homozygotes (OR = 2.62), AG + GG combined genotypes (OR = 2.98), and G mutant alleles of TF rs1867503 (OR = 1.94) were associated with a significantly elevated risk of ASD. Likewise, AG heterozygotes (OR = 2.92), GG mutant homozygotes (OR = 2.36), AG + GG combined genotypes (OR = 2.72), and G minor alleles of TCF4 rs9951150 (OR = 1.92) were associated with a significantly elevated risk of ASD.

CONCLUSIONS

Our results indicate that TF rs1867503 and TCF4 rs9951150 polymorphisms may be strongly associated with the development of ASD in Bangladeshi children.

Integrative Functional Genomic Analysis in Multiplex Autism Families from Kazakhstan

The study of extended pedigrees containing autism spectrum disorder- (ASD-) related broader autism phenotypes (BAP) offers a promising approach to the search for ASD candidate variants. Here, a total of 650,000 genetic markers were tested in four Kazakhstani multiplex families with ASD and BAP to obtain data on de novo mutations (DNMs), common, and rare inherited variants that may contribute to the genetic risk for developing autistic traits. The variants were analyzed in the context of gene networks and pathways. Several previously well-described enriched pathways were identified, including ion channel activity, regulation of synaptic function, and membrane depolarization. Perhaps these pathways are crucial not only for the development of ASD but also for ВАР. The results also point to several additional biological pathways (circadian entrainment, NCAM and BTN family interactions, and interaction between L1 and Ankyrins) and hub genes (CFTR, NOD2, PPP2R2B, and TTR). The obtained results suggest that further exploration of PPI networks combining ASD and BAP risk genes can be used to identify novel or overlooked ASD molecular mechanisms.

Testosterone/Epitestosterone Ratios-Further Hints to Explain Hyperandrogenemia in Children with Autism

BACKGROUND

Epitestosterone [E] has for a long time been considered as a biologically inactive androgen. However, recently a distinct antiandrogenic activity of this naturally occurring endogenous epimer of Testosterone has been demonstrated. Especially the ratios of testosterone/epitestosterone (T/E) seem to be key as inhibition of epitestosterone on androgen activity was postulated. As in autism, a higher androgen activity was implied. We, therefore, suggested higher levels of T/E ratios of children with autism versus children with typical development.

METHODS

Urine probes of 22 girls with autism (BMI 18.7 ± 4.3; average age 12.3 ± 3.8 years) and a sample of 51 controls (BMI 17.0 ± 2.6; average age 11.9 ± 4 years), as well as 61 boys with autism (BMI 17.04 ± 2. average age 11.9 ± 2.5 years) and 61 control boys (BMI 17.0 ± 2.6; average age 11.1 ± 3.0 years), were analyzed with gas chromatography mass spectrometry.

RESULTS

The average T/E ratio of all boys with autism was 2.5 ± 1.8 versus 2.4 ± 1.3 in boys with typical development, respectively. No significant difference between boys with autism versus boys with typical development could be detected (p = 0.977). In girls with autism, the average T/E ratio was 1.4 ± 0.9 versus 2.0 ± 1.4 in girls with typical development, whereby a significant difference could be detected (p = 0.0285). Further, polynomial analysis of the third degree were conducted, showing a dependence from age with reasonable coefficients of determination (0.075 < R² < 0.22, all samples).

DISCUSSION

As encompassing steroid hormone analysis are expensive and work-intensive, we hoped to find an easily applicable biomarker to support diagnostics in autism. However, as a relatively small sample of only 22 girls with autism were analyzed and menstrual cycle and pubertal status were only partly controllable through the matching of BMI and age, the question arises if it was an incidental finding. Nevertheless, one suggestion might be that epitestosterone has the effect of a competitive inhibition on the androgen receptor, which would probably help to explain the higher prevalence of autism in boys as compared to girls. Presumably, as no significant difference was detected in boys, this effect might not be as relevant from a steroid hormone perspective, and other effects such as altered 17/20-hydroxylase activity as previously shown in boys and girls with autism seem to have more relevance. Analysis of larger samples, including plenty of metabolites and enzymatic cascades, as well as the role of backdoor pathway activity of androgen synthesis of girls with autism, are demanded in order to validate current findings of altered steroid hormones in autism.

Is There Such a Thing as "Anti-Nutrients"? A Narrative Review of Perceived Problematic Plant Compounds

Plant-based diets are associated with reduced risk of lifestyle-induced chronic diseases. The thousands of phytochemicals they contain are implicated in cellular-based mechanisms to promote antioxidant defense and reduce inflammation. While recommendations encourage the intake of fruits and vegetables, most people fall short of their target daily intake. Despite the need to increase plant-food consumption, there have been some concerns raised about whether they are beneficial because of the various ‘anti-nutrient’ compounds they contain. Some of these anti-nutrients that have been called into question included lectins, oxalates, goitrogens, phytoestrogens, phytates, and tannins. As a result, there may be select individuals with specific health conditions who elect to decrease their plant food intake despite potential benefits. The purpose of this narrative review is to examine the science of these ‘anti-nutrients’ and weigh the evidence of whether these compounds pose an actual health threat.

Oxalate Content and Antioxidant Activity of Different Ethnic Foods

OBJECTIVE

There is not enough information on the classification of oxalate content in several foods, particularly in ethnic foods, to recommend their consumption in subjects with urolithiasis (UL). The objective of the present study was to generate reliable information on the oxalate content and antioxidant activity in different foods and classify them by very low, low, medium, high and very high oxalate content and antioxidant activity.

METHODS

The oxalate content of 109 foods including ethnic foods was assessed by an enzymatic assay, and the antioxidant activity was measured by the oxygen radical absorbance capacity to determine the oxalate/antioxidant activity ratio. Oxalate consumption was then evaluated in 400 subjects with overweight and obesity using 24-h dietary recalls.

RESULTS

The main foods with high oxalate content were raw spinach, huanzontle, purslane, chard, almond, and toasted and sweetened roasted amaranth. The highest antioxidant activity was found in strawberries, all types of chocolates, roselle, morita peppers, and pinolillo. Subjects with overweight or obesity exceed the dietary oxalate daily intake recommendation.

CONCLUSIONS

The classification of foods by their oxalate content and antioxidant activity will be very useful to generate nutritional recommendation in different diseases, mainly UL.

Dietary Approaches to the Management of Autism Spectrum Disorders

This chapter reviews the literature surrounding autism spectrum disorders (ASD) and their relation to gastrointestinal (GI), behavioral, neurological, and immunological functioning. Individuals with ASD often have poor GI health, including bowel motility issues, autoimmune and/or other adverse responses to certain foods, and lack of necessary nutrient absorption. These issues may be caused or exacerbated by restrictive behavioral patterns (e.g., preference for sweet and salty foods and/or refusal of healthy foods). Those individuals with GI issues tend to demonstrate more behavioral deficits (e.g., irritability, agitation, hyperactivity) and also tend to have an imbalance in overall gut microbiome composition, thus corroborating several studies that have implicated brain-gut pathways as potential mediators of behavioral dysfunction.We examine the literature regarding dietary approaches to managing ASDs, including elimination diets for gluten, casein, or complex carbohydrates, a ketogenic diet, and a low oxalate diet. We also explore the research examining dietary supplements such as fatty acids, pro- and prebiotics, vitamins, minerals, glutathione, phytochemicals, and hormones. The research on dietary approaches to managing ASDs is limited and the results are mixed. However, a few approaches, such as the gluten-free/casein-free diet, fatty acid supplementation, and pre/probiotics have generally demonstrated improved GI and associated behavioral symptoms. Given that GI issues seem to be overrepresented in ASD populations, and that GI issues have been associated with a number behavioral and neurological deficits, dietary manipulation may offer a cheap and easily implemented approach to improve the lives of those with ASD.

Interplay Between Peripheral and Central Inflammation in Autism Spectrum Disorders: Possible Nutritional and Therapeutic Strategies

Pre- and post-natal factors can affect brain development and function, impacting health outcomes with particular relevance to neurodevelopmental diseases, such as autism spectrum disorders (ASDs). Maternal obesity and its associated complications have been related to the increased risk of ASDs in offspring. Indeed, animals exposed to maternal obesity or high fat diets are prone to social communication impairment and repetitive behavior, the hallmarks of autism. During development, fatty acids and sugars, as well as satiety hormones, like insulin and leptin, and inflammatory factors related to obesity-induced low grade inflammation, could play a role in the impairment of neuroendocrine system and brain neuronal circuits regulating behavior in offspring. On the other side, post-natal factors, such as mode of delivery, stress, diet, or antibiotic treatment are associated to a modification of gut microbiota composition, perturbing microbiota-gut-brain axis. Indeed, the interplay between the gastrointestinal tract and the central nervous system not only occurs through neural, hormonal, and immune pathways, but also through microbe-derived metabolic products. The modification of unhealthy perinatal and postnatal environment, manipulation of gut microbiota, nutritional, and dietary interventions could represent possible strategies in preventing or limiting ASDs, through targeting inflammatory process and gut microbiota.

Antipurinergic therapy for autism-An in-depth review

Are the symptoms of autism caused by a treatable metabolic syndrome that traces to the abnormal persistence of a normal, alternative functional state of mitochondria? A small clinical trial published in 2017 suggests this is possible. Based on a new unifying theory of pathogenesis for autism called the cell danger response (CDR) hypothesis, this study of 10 boys, ages 5-14years, showed that all 5 boys who received antipurinergic therapy (APT) with a single intravenous dose of suramin experienced improvements in all the core symptoms of autism that lasted for 5-8weeks. Language, social interaction, restricted interests, and repetitive movements all improved. Two children who were non-verbal spoke their first sentences. None of these improvements were observed in the placebo group. Larger and longer studies are needed to confirm this promising discovery. This review introduces the concept of M2 (anti-inflammatory) and M1 (pro-inflammatory) mitochondria that are polarized along a functional continuum according to cell stress. The pathophysiology of the CDR, the complementary functions of M1 and M2 mitochondria, relevant gene-environment interactions, and the metabolic underpinnings of behavior are discussed as foundation stones for understanding the improvements in ASD behaviors produced by antipurinergic therapy in this small clinical trial.

Crystal clear cerebral ultrasound images mimicking acute asphyxia in an infant with primary hyperoxaluria

Genetic deficiencies in enzymes involved in glyoxylate metabolism lead to primary hyperoxaluria (PH) type I, typically characterized by deposition of oxalate crystals in kidneys. A 2-month-old infant was admitted, and was diagnosed with renal failure. Abdominal ultrasound images revealed enlarged and hyperechoic kidneys. Additionally, on cerebral ultrasound (CUS) hyperechoic changes of thalami and basal ganglia were noted, reminiscent of perinatal hypoxic-ischemic brain damage. However, MRI of the brain did not show any abnormal signal intensities compatible with asphyxia. The hyperechoic appearance of deep grey matter, in particular putamen, was therefore not due to asphyxiated brain damage but seemed related to the deposition of oxalate salts. Moreover, macular crystals were detected at ophthalmoscopy. Our case report shows the potential of US imaging to detect deposition of crystals not only in kidneys but also in brain mimicking, perinatal asphyxia.

The chemical disruption of human metabolism

BACKGROUND

Recent evidence highlights the reality of unprecedented human exposure to toxic chemical agents found throughout our environment - in our food and water supply, in the air we breathe, in the products we apply to our skin, in the medical and dental materials placed into our bodies, and even within the confines of the womb. With biomonitoring confirming the widespread bioaccumulation of myriad toxicants among population groups, expanding research continues to explore the pathobiological impact of these agents on human metabolism.

METHODS

This review was prepared by assessing available medical and scientific literature from Medline as well as by reviewing several books, toxicology journals, government publications, and conference proceedings. The format of a traditional integrated review was chosen.

RESULTS

Toxicant exposure and accrual has been linked to numerous biochemical and pathophysiological mechanisms of harm. Some toxicants effect metabolic disruption via multiple mechanisms.

CONCLUSIONS

As a primary causative determinant of chronic disease, toxicant exposures induce metabolic disruption in myriad ways, which consequently result in varied clinical manifestations, which are then categorized by health providers into innumerable diagnoses. Chemical disruption of human metabolism has become an etiological determinant of much illness throughout the lifecycle, from neurodevelopmental abnormalities in-utero to dementia in the elderly.

Relationship between adipic acid concentration and the core symptoms of autism spectrum disorders

Dicarboxylic acids are an important source of information about metabolism and potential physiopathological alterations in children with autism spectrum disorders (ASDs). We measured the concentration between dicarboxylic adipic and suberic acids in children with an ASD and typically-developing (TD) children and analyzed any relationships between the severity of the core symptoms of ASDs and other clinical features (drugs, supplements, drugs, or diet). The core symptoms of autism were evaluated using the DSM-IV criteria, and adipic acid and suberic acid were measured in urine samples. Overall, no increase in the concentration of adipic acid in children with ASDs compared to TD children, however when considering vitamin B supplementation in ASD there were significantly increased level of urinary adipic acid in children with an ASD not taking vitamin B supplementation compared to supplemented children or to TD children. No significant difference were observed in suberic acid. Interestingly, the increase in adipic acid concentration was significantly and indirectly correlated with the severity of the deficit in socialization and communication skills in children with an ASD. Therefore, therapeutic treatments aimed at decreasing adipic acid concentration might not be beneficial for treating the core symptoms of ASDs.

Potential Etiologic Factors of Microbiome Disruption in Autism

PURPOSE

The primary purpose of this article was to consider the candidate disruptors of the development of a healthy microbiome in patients with autism. The reported abnormalities in the microbiome of individuals with autism are discussed.

METHODS

This selected review used data from published articles related to the assessment of microbiota in autism. Evidence-based support of factors known to affect the intestinal microbiome in individuals with autism are presented. Proposed interventions are evaluated and discussed.

FINDINGS

Studies that have investigated the intestinal microbiome in patients with autism have reported significant differences versus unaffected controls. Increased clostridial species in autism have been reported in several studies. These differences may have resulted from a number of environmental factors. Microbiome alterations that might contribute to the development of autism include altered immune function and bacterial metabolites.

IMPLICATIONS

Efforts to modify microbial imbalances through a variety of interventions are addressed. Focusing on mechanisms that drive imbalances in the microbiome may affect the development of disease. Altered intestinal health may contribute to the development of autistic behaviors or autism itself. Interventions aimed at improving intestinal health may favorably affect the microbiome and autism.

Pharmacometabolomics-aided Pharmacogenomics in Autoimmune Disease

Inter-individual variability has been a major hurdle to optimize disease management. Precision medicine holds promise for improving health and healthcare via tailor-made therapeutic strategies. Herein, we outline the paradigm of "pharmacometabolomics-aided pharmacogenomics" in autoimmune diseases. We envisage merging pharmacometabolomic and pharmacogenomic data (to address the interplay of genomic and environmental influences) with information technologies to facilitate data analysis as well as sense- and decision-making on the basis of synergy between artificial and human intelligence. Humans can detect patterns, which computer algorithms may fail to do so, whereas data-intensive and cognitively complex settings and processes limit human ability. We propose that better-informed, rapid and cost-effective omics studies need the implementation of holistic and multidisciplinary approaches.

Assessing the iron delivery efficacy of transferrin in clinical samples by native electrospray ionization mass spectrometry

Serum transferrin is a key player in iron homeostasis, and its ability to deliver iron to cells via the endosomal pathway critically depends on the presence of carbonate that binds this protein synergistically with ferric ion. Oxalate is another ubiquitous anionic species that can act as a synergistic anion, and in fact its interaction with transferrin is notably stronger compared to carbonate, preventing the protein from releasing the metal in the endosomal environment. While this raises concerns that high oxalate levels in plasma may interfere with iron delivery to tissues, concentration of free oxalate in blood appears to be a poor predictor of impeded availability of iron, as previous studies showed that it cannot displace carbonate from ferro-transferrin on a physiologically relevant time scale under the conditions mimicing plasma. In this work we present a new method that allows different forms of ferro-transferrin (carbonate- vs. oxalate-bound) to be distinguished from each other by removing this protein from plasma without altering the composition of the protein/metal/synergistic anion complexes, and determining their accurate masses using native electrospray ionization mass spectrometry (ESI MS). The new method has been validated using a mixture of recombinant proteins, followed by its application to the analysis of clinical samples of human plasma, demonstrating that native ESI MS can be used in clinical analysis.

Gastrointestinal symptoms and autism spectrum disorder: links and risks - a possible new overlap syndrome

Autism spectrum disorder (ASD) is a genetically determined neurodevelopmental brain disorder presenting with restricted, repetitive patterns of behaviors, interests, and activities, or persistent deficits in social communication and social interaction. ASD is characterized by many different clinical endophenotypes and is potentially linked with certain comorbidities. According to current recommendations, children with ASD are at risk of having alimentary tract disorders - mainly, they are at a greater risk of general gastrointestinal (GI) concerns, constipation, diarrhea, and abdominal pain. GI symptoms may overlap with ASD core symptoms through different mechanisms. These mechanisms include multilevel pathways in the gut-brain axis contributing to alterations in behavior and cognition. Shared pathogenetic factors and pathophysiological mechanisms possibly linking ASD and GI disturbances, as shown by most recent studies, include intestinal inflammation with or without autoimmunity, immunoglobulin E-mediated and/or cell-mediated GI food allergies as well as gluten-related disorders (celiac disease, wheat allergy, non-celiac gluten sensitivity), visceral hypersensitivity linked with functional abdominal pain, and dysautonomia linked with GI dysmotility and gastroesophageal reflux. Dysregulation of the gut microbiome has also been shown to be involved in modulating GI functions with the ability to affect intestinal permeability, mucosal immune function, and intestinal motility and sensitivity. Metabolic activity of the microbiome and dietary components are currently suspected to be associated with alterations in behavior and cognition also in patients with other neurodegenerative diseases. All the above-listed GI factors may contribute to brain dysfunction and neuroinflammation depending upon an individual patient's genetic vulnerability. Due to a possible clinical endophenotype presenting as comorbidity of ASD and GI disorders, we propose treating this situation as an "overlap syndrome". Practical use of the concept of an overlap syndrome of ASD and GI disorders may help in identifying those children with ASD who suffer from an alimentary tract disease. Unexplained worsening of nonverbal behaviors (agitation, anxiety, aggression, self-injury, sleep deprivation) should alert professionals about this possibility. This may shorten the time to diagnosis and treatment commencement, and thereby alleviate both GI and ASD symptoms through reducing pain, stress, or discomfort. Furthermore, this may also protect children against unnecessary dietary experiments and restrictions that have no medical indications. A personalized approach to each patient is necessary. Our understanding of ASDs has come a long way, but further studies and more systematic research are warranted.

Glyphosate, pathways to modern diseases III: Manganese, neurological diseases, and associated pathologies

Manganese (Mn) is an often overlooked but important nutrient, required in small amounts for multiple essential functions in the body. A recent study on cows fed genetically modified Roundup(®)-Ready feed revealed a severe depletion of serum Mn. Glyphosate, the active ingredient in Roundup(®), has also been shown to severely deplete Mn levels in plants. Here, we investigate the impact of Mn on physiology, and its association with gut dysbiosis as well as neuropathologies such as autism, Alzheimer's disease (AD), depression, anxiety syndrome, Parkinson's disease (PD), and prion diseases. Glutamate overexpression in the brain in association with autism, AD, and other neurological diseases can be explained by Mn deficiency. Mn superoxide dismutase protects mitochondria from oxidative damage, and mitochondrial dysfunction is a key feature of autism and Alzheimer's. Chondroitin sulfate synthesis depends on Mn, and its deficiency leads to osteoporosis and osteomalacia. Lactobacillus, depleted in autism, depend critically on Mn for antioxidant protection. Lactobacillus probiotics can treat anxiety, which is a comorbidity of autism and chronic fatigue syndrome. Reduced gut Lactobacillus leads to overgrowth of the pathogen, Salmonella, which is resistant to glyphosate toxicity, and Mn plays a role here as well. Sperm motility depends on Mn, and this may partially explain increased rates of infertility and birth defects. We further reason that, under conditions of adequate Mn in the diet, glyphosate, through its disruption of bile acid homeostasis, ironically promotes toxic accumulation of Mn in the brainstem, leading to conditions such as PD and prion diseases.

Human serum transferrin: is there a link among autism, high oxalate levels, and iron deficiency anemia?

It has been previously suggested that large amounts of oxalate in plasma could play a role in autism by binding to the bilobal iron transport protein transferrin (hTF), thereby interfering with iron metabolism by inhibiting the delivery of iron to cells. By examining the effect of the substitution of oxalate for the physiologically utilized synergistic carbonate anion in each lobe of hTF, we sought to provide a molecular basis for or against such a role. Our work clearly shows both qualitatively (6 M urea gels) and quantitatively (kinetic analysis by stopped-flow spectrofluorimetry) that the presence of oxalate in place of carbonate in each binding site of hTF does indeed greatly interfere with the removal of iron from each lobe (in the absence and presence of the specific hTF receptor). However, we also clearly demonstrate that once the iron is bound within each lobe of hTF, neither anion can displace the other. Additionally, as verified by urea gels and electrospray mass spectrometry, formation of completely homogeneous hTF-anion complexes requires that all iron must first be removed and hTF then reloaded with iron in the presence of either carbonate or oxalate. Significantly, experiments described here show that carbonate is the preferred binding partner; i.e., even if an equal amount of each anion is available during the iron loading process, the hTF-carbonate complex is formed.

Modeling autism: a systems biology approach

Autism is the fastest growing developmental disorder in the world today. The prevalence of autism in the US has risen from 1 in 2500 in 1970 to 1 in 88 children today. People with autism present with repetitive movements and with social and communication impairments. These impairments can range from mild to profound. The estimated total lifetime societal cost of caring for one individual with autism is $3.2 million US dollars. With the rapid growth in this disorder and the great expense of caring for those with autism, it is imperative for both individuals and society that techniques be developed to model and understand autism. There is increasing evidence that those individuals diagnosed with autism present with highly diverse set of abnormalities affecting multiple systems of the body. To this date, little to no work has been done using a whole body systems biology approach to model the characteristics of this disorder. Identification and modelling of these systems might lead to new and improved treatment protocols, better diagnosis and treatment of the affected systems, which might lead to improved quality of life by themselves, and, in addition, might also help the core symptoms of autism due to the potential interconnections between the brain and nervous system with all these other systems being modeled. This paper first reviews research which shows that autism impacts many systems in the body, including the metabolic, mitochondrial, immunological, gastrointestinal and the neurological. These systems interact in complex and highly interdependent ways. Many of these disturbances have effects in most of the systems of the body. In particular, clinical evidence exists for increased oxidative stress, inflammation, and immune and mitochondrial dysfunction which can affect almost every cell in the body. Three promising research areas are discussed, hierarchical, subgroup analysis and modeling over time. This paper reviews some of the systems disturbed in autism and suggests several systems biology research areas. Autism poses a rich test bed for systems biology modeling techniques.

Rapid oxalate determination in blood and synthetic urine using a newly developed oxometer

Blood and urine oxalate determinations have been limited to the laboratory setting because of complex sample storage and processing methods as well as the need for color spectrophotometry and ion chromatography. We hypothesized that glucometer test strips, impregnated with glucose oxidase and dyes that measure secondary hydrogen peroxide production, could be infused with oxalate oxidase and produce enhanced color changes in the presence of oxalate. By increasing the amount of sodium oxalate in fresh blood, we found that glucometer-measured oxalate increased on a linear scale. In addition, oxalate levels in synthetic urine could be measured using a visual scale, suggesting that strip dwell time or oxalate/oxalate oxidase concentrations could be manipulated to enhance optimal sensitivity. Although further testing is necessary, this simple, first-generation oxometer may eventually allow point of care testing in the home or office, empowering patients with oxalate-based medical conditions and giving healthcare providers real-time oxalate feedback.