A ketogenic diet differentially affects neuron and astrocyte transcription.

Ketogenic diets (KDs) alter brain metabolism. Multiple mechanisms may account for their effects, and different brain regions may variably respond. Here, we considered how a KD affects brain neuron and astrocyte transcription. We placed male C57Bl6/N mice on either a 3-month KD or chow diet, generated enriched neuron and astrocyte fractions, and used RNA-Seq to assess transcription. Neurons from KD-treated mice generally showed transcriptional pathway activation while their astrocytes showed a mix of transcriptional pathway suppression and activation. The KD especially affected pathways implicated in mitochondrial and endoplasmic reticulum function, insulin signaling, and inflammation. An unbiased analysis of KD-associated expression changes strongly implicated transcriptional pathways altered in AD, which prompted us to explore in more detail the potential molecular relevance of a KD to AD. Our results indicate a KD differently affects neurons and astrocytes, and provide unbiased evidence that KD-induced brain effects are potentially relevant to neurodegenerative diseases such as AD.

The efficacy comparison of classic ketogenic diet and modified Atkins diet in children with refractory epilepsy: a clinical trial.

Dietary therapy has an important role in the therapeutic process in children suffering refractory epilepsy. There are two kinds of dietary therapy which are the most common in children with refractory epilepsy: The classic ketogenic diet (KD) and the modified Atkins diet (MAD). The purpose of the present study was to compare the efficacy, tolerability, and compliance of these two dietary therapies in the children who have refractory epilepsy during 6 months of treatment. From March 2017 to November 2018, 45 children aged 2-15 years who had refractory epilepsy were randomly allocated in KD or MAD group. The intervention period was 6 months in both groups. The frequencies of seizures were determined from parental reports and were compared between the groups. The patients with upper than 50% reduction in seizure frequency were deemed as responders to the diets. Twenty-four patients were assigned to the KD and 11 patients to the MAD. Overall, 45.8% of children treated with the KD and 45.5% of children treated with MAD had over than 50% response to the diet therapies. The difference was not statistically significant (P = 0.437). The MAD was more advantageous regarding better tolerability and fewer side effects. There is not much difference regarding the efficacy between the MAD and classic KD. The MAD with fewer side effects may be more suitable as the first line of dietary therapy in children with refractory epilepsy.

Effect of ketogenic diet versus regular diet on voice quality of patients with Parkinson's disease.

Diets that have effects on health problems can vary in their composition. Whilst following a regular diet (RD) a person typically consumes about 30% of calories from fat. Ketogenic diet (KD) is a form of diet whereby a person consumes as much as 90% of calories from fat. KD has been trialed as a treatment for neurological diseases and obesity. Parkinson's disease (PD) is a neurologic disease that impacts the quality of voice. Voice Handicap Index (VHI) is a test that gives information to clinical and physiological assessment about voice. We assessed the impact of KD and RD on voice quality (VQ). Seventy-four patients with PD who reported a voice disorder related to their disease were randomly assigned to the KD or RD groups. We investigated the VHI change of subjects before and 3 months after diet. Sixty-eight PD patients completed the study. Baseline VHI values did not differ significantly between groups. All mean VHI parameters improved in KD group (p˂ 0.001). Currently there are different therapies that address speech and voice disorders in patients with PD. As such KD may be an alternative therapy to improve VQ of patients with PD. A larger sample size is necessary to determine the role and pathophysiology of KD on VQ of PD patients.

Challenges in telemedicine for adult patients with drug-resistant epilepsy undergoing ketogenic diet treatment during the COVID-19 pandemic in the public healthcare system in Brazil.

Hygienic and sanitary measures and social distancing policies implemented during the new coronavirus disease - COVID-19 - pandemic have altered the care and follow-up provided by healthcare professionals for patients with chronic diseases, including patients with epilepsy (PWEs). Telemedicine has become a solution for the healthcare of PWEs in many developed countries. In this short communication, we trace a particular perspective for the application of telemedicine for PWEs undergoing ketogenic diet (KD) treatment, considering the social and economic difficulties faced by healthcare teams in resource-poor countries, such as Brazil. During the pandemic, financial strain was the main impediment to following KD. The pandemic increased socioeconomic insecurity and access to KD-related products, as well as increasing anxiety in 71% of PWE, impacting their KD treatment follow-up. The challenges of telemedicine in Brazil include not only social and economic issues but also access to food, healthcare services, and education for the population, in addition to digital inclusion.

Effects of modified Atkins diet on thyroid function in adult patients with pharmacoresistant epilepsy.

INTRODUCTION: The use of ketogenic diet as a supplement to antiseizure medication (ASM) in refractory epilepsy has increased the past decades. This high-fat, low-carbohydrate diet mimics the metabolic state of fasting and is generally well-tolerated. However, the long-term adverse effects of the diet are unclear. The purpose of this study was to investigate whether the modified Atkins diet (MAD), a variant of the ketogenic diet, may have an impact on thyroid hormone levels. METHODS: We assessed thyroid function by measuring thyroid stimulation hormone (TSH), fT4, T3, fT3, and rT3 before diet start (baseline) and after 12 weeks on the diet in 53 adult patients with drug-resistant epilepsy. Further, we examined the correlation between the changes in thyroid function during dietary treatment and type of (i) change in seizure frequency, (ii) drugs in use, and (iii) degree of ketosis. RESULTS: After 12 weeks on the diet, we found a significant reduction in T3 and fT3 values (13.4% and 10.6%, respectively) and a significant increase in fT4 values (12.1%) compared with baseline. In addition, there was an insignificant increase in TSH and rT3. These changes were similar in women and men, and there was no correlation to drugs in use (enzyme-inducing vs. nonenzyme-inducing drugs), changes in seizure frequency, or level of ketosis. CONCLUSION: This study indicates that dietary treatment for epilepsy may bring about a modest fall in thyroid hormone levels. This could be relevant for those patients with low thyroid hormones and those treated with ASMs known to lower thyroid hormone levels. A cumulative effect of ASMs, low basal thyroid hormone levels, and ketogenic diet may therefore be of clinical importance in the case of thyroid hormones when treating patients with MAD.

Male mice placed on a ketogenic diet from postnatal day (P) 21 through adulthood have reduced growth, are hypoactive, show increased freezing in a conditioned fear paradigm, and have spatial learning deficits.

The ketogenic diet (KD) is a non-pharmacological treatment for specific types of epilepsy. In addition, it has been shown to be effective in mitigating other neurologic disorders. The KD is also effective in reducing body mass, leading to an increase in use by the general population for weight loss. As the popularity of the clinical and general use of the KD has increased, it is important to develop adequate mouse models to better understand the effects of the KD in both normal and diseased states. Many times, the best outcome for disorders treatable with the KD would be achieved by commencing treatment in early life. Few studies have evaluated the cognitive effect of starting the KD in early life. To better understand these effects, male C57BL6/J mice were placed on a KD from postnatal day (P) 21 through young adulthood (~P90). KD-fed mice had increased blood ketone levels, reduced blood glucose, and reduced weight gain versus mice fed a control diet (CD). The weight loss in the KD-fed mice was not accompanied by a change in body fat percentage, suggesting that there was a loss of lean mass. Behavioral testing began on P60 while the mice were still on the diet. KD-fed mice were hypoactive with CD-fed mice. In the Morris water maze, KD-fed mice showed decreased path efficiency, suggesting a spatial learning deficits. No differences were observed in spatial memory or in novel object recognition memory. In a contextual and conditioned fear paradigm, the KD-fed mice had an increase in freezing behavior. These data suggest that early-life exposure to a KD leads to impaired body composition and long-term cognitive changes.

Pharmacoresistance - Epidemiology, mechanisms, and impact on epilepsy treatment.

Understanding the natural history of and factors associated with pharmacoresistant epilepsy provides the foundation for formulating mechanistic hypotheses that can be evaluated to drive the development of novel treatments. This article reviews the modern definition of drug-resistant epilepsy, its prevalence and incidence, risk factors, hypothesized mechanisms, and the implication of recognizing pharmacoresistance in therapeutic strategies. This article is part of the special issue entitled 'New Epilepsy Therapies for the 21st Century - From Antiseizure Drugs to Prevention, Modification and Cure of Epilepsy'.

Epigenetics and epilepsy prevention: The therapeutic potential of adenosine and metabolic therapies.

Prevention of epilepsy and its progression remains the most urgent need for epilepsy research and therapy development. Novel conceptual advances are required to meaningfully address this fundamental challenge. Maladaptive epigenetic changes, which include methylation of DNA and acetylation of histones - among other mechanisms, are now well recognized to play a functional role in the development of epilepsy and its progression. The methylation hypothesis of epileptogenesis suggests that changes in DNA methylation are implicated in the progression of the disease. In this context, global DNA hypermethylation is particularly associated with chronic epilepsy. Likewise, acetylation changes of histones have been linked to epilepsy development. Clinical as well as experimental evidence demonstrate that epilepsy and its progression can be prevented by metabolic and biochemical manipulations that target previously unrecognized epigenetic functions contributing to epilepsy development and maintenance of the epileptic state. This review will discuss epigenetic mechanisms implicated in epilepsy development as well as metabolic and biochemical interactions thought to drive epileptogenesis. Therefore, metabolic and biochemical mechanisms are identified as novel targets for epilepsy prevention. We will specifically discuss adenosine biochemistry as a novel therapeutic strategy to reconstruct the DNA methylome as antiepileptogenic strategy as well as metabolic mediators, such as beta-hydroxybutyrate, which affect histone acetylation. Finally, metabolic dietary interventions (such as the ketogenic diet) which have the unique potential to prevent epileptogenesis through recently identified epigenetic mechanisms will be reviewed. This article is part of the special issue entitled 'New Epilepsy Therapies for the 21st Century - From Antiseizure Drugs to Prevention, Modification and Cure of Epilepsy'.

Prognostic utility of hypsarrhythmia scoring in children with West syndrome after ketogenic diet.

OBJECTIVE: The aim of this study was to evaluate the clinical efficacy and electroencephalographic (EEG) changes of West syndrome after ketogenic diet (KD) therapy and to explore the correlation of EEG features and clinical efficacy. PATIENTS AND METHODS: We retrospectively studied 39 patients with West syndrome who accepted KD therapy from May 2011 to October 2017. Outcomes including clinical efficacy and EEG features with hypsarrhythmia severity scores were analyzed. RESULTS: After 3 months of treatment, 20 patients (51.3%) had ≥50% seizure reduction, including 4 patients (10.3%) who became seizure-free. After 6 months of treatment, 4 patients remained seizure free, 12 (30.8%) had 90-99% seizure reduction, 8 (20.5%) had a reduction of 50-89%, and 15 (38.5%) had <50% reduction. Hypsarrhythmia scores were significantly decreased at 3 months of KD. They were associated with seizure outcomes at 6 months independent of gender, the course of disease and etiologies. Patients with a hypsarrhythmia score ≥8 at 3 months of therapy may not be benefited from KD. CONCLUSION: Our findings suggest a potential benefit of KD for patients with drug-resistant West syndrome. Early change of EEG after KD may be a predictor of a patient's response to the therapy.

Metabolic interventions in Autism Spectrum Disorder.

Metabolic interventions including special diets and supplements are commonly used in Autism Spectrum Disorder (ASD). Yet little is known about how these interventions, typically initiated by caregivers, may affect metabolic function or the core symptoms of ASD. This review examines possible direct and indirect roles for metabolism in the core symptoms of ASD as well as evidence for metabolic dysfunction and nutritional deficiencies. We also discuss some of the most popular diets and supplements used in our patient population and suggest strategies for discussing the utility of these interventions with patients, families, and caregivers.

Do certain subpopulations of adults with drug-resistant epilepsy respond better to modified ketogenic diet treatments? Evaluation based on prior resective surgery, type of epilepsy, imaging abnormalities, and vagal nerve stimulation.

OBJECTIVE: Adults with drug-resistant epilepsy (DRE) are among the most challenging to treat. This study assessed whether specific subpopulations of adult patients with refractory epilepsy responded differently to modified ketogenic diet (MKD) therapy. METHODS: Changes in seizure frequency, severity, and quality of life (QOL) were retrospectively analyzed based on pre-MKD surgical history, type of epilepsy, imaging findings, and vagal nerve stimulation (VNS) history among adults, ≥17 years of age, with DRE, receiving MKD therapy for three months. Additionally, particular attention was made to medication and VNS adjustments. RESULTS: Responder rates in seizure frequency, severity, and QOL reported among those with prior surgery were 56%, 75%, and 94%, respectively. Among those with focal epilepsy: 57%, 76%, and 76% had improvements in seizure frequency, seizure severity, and QOL, respectively whereas 83% improvement was seen for all three measures in those with generalized epilepsy. Among those with abnormal imaging: just over 50% reported improvements on all measures. For those with VNS, 53%, 63%, and 95% had improvements in seizure frequency, seizure severity, and QOL, respectively. No statistical differences in seizure frequency, severity, or QOL were noted between groups based on prediet surgical history, seizure type, imaging abnormalities, or VNS history. Compared with expected improvement from medication adjustment alone, significant improvement was seen for all groups; notably, the Z-test for proportions for the surgery group, when compared with placebo responder rates at 20%, was 3.6, p < 0.001. CONCLUSIONS: Modified ketogenic diet therapies are effective in improving seizure frequency, severity, and QOL and may offer the best chance for improvement among those whose seizures have persisted despite surgical intervention and VNS therapy. All types of epilepsy respond to MKDs, and possibly those with generalized epilepsy may respond better.

A Ketogenic Diet Improves Mitochondrial Biogenesis and Bioenergetics via the PGC1α-SIRT3-UCP2 Axis.

A ketogenic diet (KD; high-fat, low-carbohydrate) can benefit refractory epilepsy, but underlying mechanisms are unknown. We used mice inducibly expressing a mutated form of the mitochondrial DNA repair enzyme UNG1 (mutUNG1) to cause progressive mitochondrial dysfunction selectively in forebrain neurons. We examined the levels of mRNAs and proteins crucial for mitochondrial biogenesis and dynamics. We show that hippocampal pyramidal neurons in mutUNG1 mice, as well as cultured rat hippocampal neurons and human fibroblasts with H2O2 induced oxidative stress, improve markers of mitochondrial biogenesis, dynamics and function when fed on a KD, and when exposed to the ketone body ß-hydroxybutyrate, respectively, by upregulating PGC1α, SIRT3 and UCP2, and (in cultured cells) increasing the oxygen consumption rate (OCR) and the NAD+/NADH ratio. The mitochondrial level of UCP2 was significantly higher in the perikarya and axon terminals of hippocampus CA1 pyramidal neurons in KD treated mutUNG1 mice compared with mutUNG1 mice fed a standard diet. The ß-hydroxybutyrate receptor GPR109a (HCAR2), but not the structurally closely related lactate receptor GPR81 (HCAR1), was upregulated in mutUNG1 mice on a KD, suggesting a selective influence of KD on ketone body receptor mechanisms. We conclude that progressive mitochondrial dysfunction in mutUNG1 expressing mice causes oxidative stress, and that exposure of animals to KD, or of cells to ketone body in vitro, elicits compensatory mechanisms acting to augment mitochondrial mass and bioenergetics via the PGC1α-SIRT3-UCP2 axis (The compensatory processes are overwhelmed in the mutUNG1 mice by all the newly formed mitochondria being dysfunctional).

Application of Bayesian evidence synthesis to modelling the effect of ketogenic therapy on survival of high grade glioma patients.

BACKGROUND: Ketogenic therapy in the form of ketogenic diets or calorie restriction has been proposed as a metabolic treatment of high grade glioma (HGG) brain tumors based on mechanistic reasoning obtained mainly from animal experiments. Given the paucity of clinical studies of this relatively new approach, our goal is to extrapolate evidence from the greater number of animal studies and synthesize it with the available human data in order to estimate the expected effects of ketogenic therapy on survival in HGG patients. At the same time we are using this analysis as an example for demonstrating how Bayesianism can be applied in the spirit of a circular view of evidence. RESULTS: A Bayesian hierarchical model was developed. Data from three human cohort studies and 17 animal experiments were included to estimate the effects of four ketogenic interventions (calorie restriction/ketogenic diets as monotherapy/combination therapy) on the restricted mean survival time ratio in humans using various assumptions for the relationships between humans, rats and mice. The impact of different biological assumptions about the relevance of animal data for humans as well as external information based on mechanistic reasoning or case studies was evaluated by specifying appropriate priors. We provide statistical and philosophical arguments for why our approach is an improvement over existing (frequentist) methods for evidence synthesis as it is able to utilize evidence from a variety of sources. Depending on the prior assumptions, a 30-70% restricted mean survival time prolongation in HGG patients was predicted by the models. The highest probability of a benefit (> 90%) for all four ketogenic interventions was obtained when adopting an enthusiastic prior based on previous case reports together with assuming synergism between ketogenic therapies with other forms of treatment. Combinations with other treatments were generally found more effective than ketogenic monotherapy. CONCLUSIONS: Combining evidence from both human and animal studies is statistically possible using a Bayesian approach. We found an overall survival-prolonging effect of ketogenic therapy in HGG patients. Our approach is best compatible with a circular instead of hierarchical view of evidence and easy to update once more data become available.

Ketogenic diet therapies in France: State of the use in 2018.

Ketogenic diets (KDs) are well-established treatments for pharmacoresistant epilepsies and some metabolic disorders. The amount of publications including evidence-based trials has continuously increased in the last 10 years. We evaluated the use of KDs in France using 2 surveys from more than ten years ago (2005 and 2008). METHODS: We conducted a new survey based on 10 questions to evaluate the evolution of the practice since 2008 and the thoughts of French pediatric neurologists on the barriers as well as possible ways to support the use of KDs. RESULTS: All centers increased their use of KDs over time. There are now 5 out of 25 centers that are prescribing the modified Atkins diet. French pediatric neurologists reported the acceptability and the everyday life burden due to KDs as the most important barriers. CONCLUSION: The use of the diet in France seems to follow the increase of knowledge in this field.

Ketogenic diet attenuates oxidative stress and inflammation after spinal cord injury by activating Nrf2 and suppressing the NF-κB signaling pathways.

Oxidative stress and inflammation are two key secondary pathological mechanisms following spinal cord injury (SCI). Ketogenic diet (KD) and its metabolite ß-hydroxybutyrate have been found to exhibit anti-oxidative and anti-inflammatory properties both in rats with SCI and in healthy rats; however, the underlying mechanisms are not yet fully understood. We investigated the effects of KD on the suppression of oxidative stress and inflammation, activation of nuclear factor-E2 related factor 2 (Nrf2), and inhibition of the nuclear factor-κB (NF-κB) signaling pathway in rats with SCI. We assessed functional recovery and evaluated the status of oxidative stress and inflammation using tests of superoxide dismutase and myeloperoxidase activity. We further assessed the presence of the proinflammatory cytokines tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), and interferon γ (IFN-γ) by ELISA. Western blotting was used to detect Nrf2 and NF-κB pathway-associated proteins in spinal cord tissue. Finally, we measured the levels of the NF-κB downstream genes TNF-α, IL-1ß, and IFN-γ by western blotting and real-time quantitative PCR. Following SCI, KD improved functional recovery, attenuated oxidative stress and inflammation, and induced Nrf2 activation. In addition, KD suppressed the NF-κB pathway and the expression of TNF-α, IL-1ß, and IFN-γ. Together, these findings provide new insight into the underlying regulatory mechanisms of KD.

Neuroketotherapeutics: A modern review of a century-old therapy.

Neuroketotherapeutics represent a class of bioenergetic medicine therapies that feature the induction of ketosis. These therapies include medium-chain triglyceride supplements, ketone esters, fasting, strenuous exercise, the modified Atkins diet, and the classic ketogenic diet. Extended experience reveals persons with epilepsy, especially pediatric epilepsy, benefit from ketogenic diets although the mechanisms that underlie its effects remain unclear. Data indicate ketotherapeutics enhance mitochondrial respiration, promote neuronal long-term potentiation, increase BDNF expression, increase GPR signaling, attenuate oxidative stress, reduce inflammation, and alter protein post-translational modifications via lysine acetylation and ß-hydroxybutyrylation. These properties have further downstream implications involving Akt, PLCγ, CREB, Sirtuin, and mTORC pathways. Further studies of neuroketotherapeutics will enhance our understanding of ketone body molecular biology, and reveal novel central nervous system therapeutic applications.

Efficacy of a ketogenic diet in resistant myoclono-astatic epilepsy: A French multicenter retrospective study.

OBJECTIVE: Recent studies have suggested that the early introduction of a ketogenic diet (KD) could improve seizure control in myoclono-astatic epilepsy (MAE). This multicenter study sought to identify the benefits of KD use on seizure control and epilepsy and on developmental outcomes in children with resistant MAE. METHODS: Fifty children who were diagnosed with severe MAE in the French network of Reference Centers for Rare Epilepsies and who were treated with KD between 2000 and 2013 were included in this study. The seizure frequency and EEG recordings were assessed two weeks before KD introduction, 2 and 6 months after, and during the last follow-up, which also included an assessment of developmental outcome. RESULTS: Patients had a median follow up of 52 months (range 13-136) and received 4.3 antiepileptic drugs [2-9] before KD introduction. Fifty-four percent (54%) of our patients were seizure-free after 6 months of KD or more, and 86% experienced more than a 70% seizure reduction after 2 months of KD. Forty-four percent (44%) of them had a clear benefit of early KD treatment (after four AEDs failed). Early KD treatment did not result in a greater seizure reduction (p=0.055), but significantly resulted in remission (p<0.028). Fifty percent of patients with resistant MAE had normal development outcomes. Earlier KD treatment, after three AEDs failed, was correlated with a better cognitive outcome (p<0.01). SIGNIFICANCE: Early introduction of KD treatment in resistant MAE has a strong, persistent anticonvulsant effect with long-term remission and better cognitive outcomes.

Decreased health care utilization and health care costs in the inpatient and emergency department setting following initiation of ketogenic diet in pediatric patients: The experience in Ontario, Canada.

OBJECTIVE: To assess the change in inpatient and emergency department utilization and health care costs in children on the ketogenic diet for treatment of epilepsy. METHODS: Data on children with epilepsy initiated on the ketogenic diet (KD) Jan 1, 2000 and Dec 31, 2010 at Ontario pediatric hospitals were linked to province wide inpatient, emergency department (ED) data at the Institute for Clinical Evaluative Sciences. ED and inpatient visits and costs for this cohort were compared for a maximum of 2 years (730days) prior to diet initiation and for a maximum of 2 years (730days) following diet initiation. KD patient were compared to matched group of children with epilepsy who did not receive the ketogenic diet (no KD). RESULTS: Children on the KD experienced a mean decrease in ED visits of 2.5 visits per person per year [95% CI (1.5-3.4)], and a mean decrease of 0.8 inpatient visits per person per year [95% CI (0.3-1.3)], following diet initiation. They had a mean decrease in ED costs of $630 [95% CI (249-1012)] per person per year and a median decrease in inpatient costs of $1059 [IQR: 7890; p<0.001] per child per year. Compared with the no KD children, children on the diet experienced a mean reduction of 2.1 ED visits per child per year [95% CI (1.0-3.2)] and a mean decrease of 0.6 [95% CI (0.1-1.1)] inpatient visits per child per year. Patients on the KD experienced a reduction of $442 [95% CI (34.4-850)] per child per year more in ED costs than the matched group. The ketogenic diet group had greater median decrease in inpatient costs per child per year than the matched group [p<0.001]. SIGNIFICANCE: Patients initiated on ketogenic diet, experienced decreased ED and inpatient visits as well as costs following diet initiation in Ontario, Canada.