The Gut Microbiota Mediates the Anti-Seizure Effects of the Ketogenic Diet

Ketogenic Diet High in Saturated Fat Promotes Colonic Claudin Expression without Changes in Intestinal Permeability to Iohexol in Healthy Mice

Ketogenic diets (KDs) have been studied in preclinical models of intestinal diseases. However, little is known of how the fat source of these diets influences the intestinal barrier. Herein, we studied the impact of four-week feeding with KD high either in saturated fatty acids (SFA-KD) or polyunsaturated linoleic acid (LA-KD) on paracellular permeability of the intestine to iohexol in healthy male C57BL/6J mice. We investigated jejunal and colonic tight junction protein expression, histological changes, and inflammatory markers (Il1b, Il6, Tnf, and Lcn2), as well as the activity and expression of intestinal alkaline phosphatase (IAP) in feces and jejunal tissue, respectively, and plasma lipopolysaccharide. KDs did not change intestinal permeability to iohexol after two or twenty-six days of feeding regardless of fat quality. SFA-KD, but not LA-KD, upregulated the colonic expression of tight junction proteins claudin-1 and -4, as well as the activity of IAP. Both KDs resulted in increased epithelial vacuolation in jejunum, and this was pronounced in SFA-KD. Jejunal Il1β expression was lower and colonic Il6 expression higher in LA-KD compared to SFA-KD. In colon, Tnf mRNA was increased in LA-KD when compared to controls. Overall, the results suggest that KDs do not influence intestinal permeability to iohexol but elicit changes in colonic tight junction proteins and inflammatory markers in both jejunum and colon. Future research will show whether these changes become of importance upon proinflammatory insults.

Our Mental Health Is Determined by an Intrinsic Interplay between the Central Nervous System, Enteric Nerves, and Gut Microbiota

Bacteria in the gut microbiome play an intrinsic part in immune activation, intestinal permeability, enteric reflex, and entero-endocrine signaling. The gut microbiota communicates with the central nervous system (CNS) through the production of bile acids, short-chain fatty acids (SCFAs), glutamate (Glu), γ-aminobutyric acid (GABA), dopamine (DA), norepinephrine (NE), serotonin (5-HT), and histamine. A vast number of signals generated in the gastrointestinal tract (GIT) reach the brain via afferent fibers of the vagus nerve (VN). Signals from the CNS are returned to entero-epithelial cells (EES) via efferent VN fibers and communicate with 100 to 500 million neurons in the submucosa and myenteric plexus of the gut wall, which is referred to as the enteric nervous system (ENS). Intercommunications between the gut and CNS regulate mood, cognitive behavior, and neuropsychiatric disorders such as autism, depression, and schizophrenia. The modulation, development, and renewal of nerves in the ENS and changes in the gut microbiome alter the synthesis and degradation of neurotransmitters, ultimately influencing our mental health. The more we decipher the gut microbiome and understand its effect on neurotransmission, the closer we may get to developing novel therapeutic and psychobiotic compounds to improve cognitive functions and prevent mental disorders. In this review, the intricate control of entero-endocrine signaling and immune responses that keep the gut microbiome in a balanced state, and the influence that changing gut bacteria have on neuropsychiatric disorders, are discussed.

Gut microbiota modification by diosgenin mediates antiepileptic effects in a mouse model of epilepsy

Diosgenin, a natural steroid saponin, holds promise as a multitarget therapeutic for various diseases, including neurodegenerative conditions. Its efficacy in slowing Alzheimer's disease, Parkinson's disease, multiple sclerosis, and stroke progression has been demonstrated. However, the role of diosgenin in anti-epilepsy and its potential connection to the modulation of the intestinal microbiota remain poorly understood. In this study, exogenous diosgenin significantly mitigated pentylenetetrazole (PTZ)-induced seizures, learning and memory deficits, and hippocampal neuronal injury. 16S ribosomal RNA (16S rRNA) sequencing revealed a reversal in the decrease of Bacteroides and Parabacteroides genera in the PTZ-induced mouse epileptic model following diosgenin treatment. Fecal microbiota transplantation (FMT) experiments illustrated the involvement of diosgenin in modulating gut microbiota and providing neuroprotection against epilepsy. Our results further indicated the repression of enteric glial cells (EGCs) activation and the TLR4-MyD88 pathway, coupled with reduced production of inflammatory cytokines in the colonic lumen, and improved intestinal barrier function in epilepsy mice treated with diosgenin or FMT. This study suggests that diosgenin plays a role in modifying gut microbiota, contributing to the alleviation of intestinal inflammation and neuroinflammation, ultimately inhibiting epilepsy progression in a PTZ-induced mouse model. Diosgenin emerges as a potential therapeutic option for managing epilepsy and its associated comorbidities.

Butyrate ameliorated the intestinal barrier dysfunction and attenuated acute pancreatitis in mice fed with ketogenic diet

Butyrate, a short-chain fatty acid (SCFA), has demonstrated significant efficacy in preventing colitis-associated inflammation. Acute pancreatitis is an acute gastrointestinal disorder characterized by increased systemic inflammation, bacterial translocation, and disrupted intestinal barrier. However, the effects and mechanisms of butyrate in attenuating acute pancreatitis remain unclear. In this study, we established two mouse models of acute pancreatitis induced by cerulein (Cer) and taurocholate (TA), which were further exacerbated by a ketogenic diet (KD). The results suggested that butyrate supplementation effectively reduced mortality rates, systemic inflammation, and intestinal barrier disruption caused by Cer- and TA-induced acute pancreatitis in mice fed a KD. Furthermore, we observed a significant reduction in gut microbiota diversity as well as overgrowth of Lachnospirales and Erysipelotrichales along with depletion of SCFAs in mice fed a KD, and these alterations were reversed by butyrate supplement. To evaluate the role of microbiota and butyrate supplement, we conducted germ-depletion trials by antibiotics. The results showed that while systemic inflammation was attenuated in mice with TA-induced pancreatitis following antibiotic treatment, the reduction in mortality remained inconclusive (p = 0.055). Importantly, the key differential change between antibiotic treatment and butyrate supplementation was found to be related to intestinal barrier dysfunction and repairment. These results suggest that butyrate plays a central role in mitigating acute pancreatitis through amelioration of intestinal barrier dysfunction.

Calorie restriction mimetic drugs could favorably influence gut microbiota leading to lifespan extension

Calorie restriction (CR) can prolong human lifespan, but enforcing long-term CR is difficult. Thus, a drug that reproduces the effects of CR without CR is required. More than 10 drugs have been listed as CR mimetics (CRM), and some of which are conventionally categorized as upstream-type CRMs showing glycolytic inhibition, whereas the others are categorized as downstream-type CRMs that regulate or genetically modulate intracellular signaling proteins. Intriguingly, recent reports have revealed the beneficial effects of CRMs on the body such as improving the host body condition via intestinal bacteria and their metabolites. This beneficial effect of gut microbiota may lead to lifespan extension. Thus, CRMs may have a dual effect on longevity. However, no reports have collectively discussed them as CRMs; hence, our knowledge about CRM and its physiological effects on the host remains fragmentary. This study is the first to present and collectively discuss the accumulative evidence of CRMs improving the gut environments for healthy lifespan extension, after enumerating the latest scientific findings related to the gut microbiome and CR. The conclusion drawn from this discussion is that CRM may partially extend the lifespan through its effect on the gut microbiota. CRMs increase beneficial bacteria abundance by decreasing harmful bacteria rather than increasing the diversity of the microbiome. Thus, the effect of CRMs on the gut could be different from that of conventional prebiotics and seemed similar to that of next-generation prebiotics.

Fibroblast growth factor 21 ameliorates behavior deficits in Parkinson's disease mouse model via modulating gut microbiota and metabolic homeostasis

AIMS

The effects of FGF21 on Parkinson's disease (PD) and its relationship with gut microbiota have not been elucidated. This study aimed to investigate whether FGF21 would attenuate behavioral impairment through microbiota-gut-brain metabolic axis in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced PD mice model.

METHODS

Male C57BL/6 mice were rendomized into 3 groups: vehicle (CON); MPTP 30 mg/kg/day i.p. injection (MPTP); FGF21 1.5 mg/kg/d i.p. injection plus MPTP 30 mg/kg/day i.p. injection (FGF21 + MPTP). The behavioral features, metabolimics profiling, and 16 s rRNA sequencing were performed after FGF21 treatment for 7 days.

RESULTS

MPTP-induced PD mice showed motor and cognitive deficits accompanied by gut microbiota dysbiosis and brain-region-specific metabolic abnormalities. FGF21 treatment dramatically attenuated motor and cognitive dysfunction in PD mice. FGF21 produced a region-specific alteration in the metabolic profile in the brain in ways indicative of greater ability in neurotransmitter metabolism and choline production. In addition, FGF21 also re-structured the gut microbiota profile and increased the relative abundance of Clostridiales, Ruminococcaceae, and Lachnospiraceae, thereby rescuing the PD-induced metabolic disorders in the colon.

CONCLUSION

These findings indicate that FGF21 could affect behavior and brain metabolic homeostasis in ways that promote a favorable colonic microbiota composition and through effects on the microbiota-gut-brain metabolic axis.

Oral microbiome alterations in epilepsy and after seizure control

Background

The existing diagnostic methods of epilepsy such as history collection and electroencephalogram have great limitations in practice, so more reliable and less difficult diagnostic methods are needed.

Methods

By characterizing oral microbiota in patients diagnosed with epilepsy (EPs) and patients whose seizures were under control (EPRs), we sought to discover biomarkers for different disease states. 16S rRNA gene sequencing was performed on 480 tongue swabs [157 EPs, 22 EPRs, and 301 healthy controls (HCs)].

Results

Compared with normal individuals, patients with epilepsy exhibit increased alpha diversity in their oral microbiota, and the oral microbial communities of the two groups demonstrate significant beta diversity differences. EPs exhibit a significant increase in the abundance of 26 genera, including Streptococcus, Granulicatella, and Kluyvera, while the abundance of 14 genera, including Peptostreptococcus, Neisseria, and Schaalia, is significantly reduced. The area under the receiver operating characteristic curve (AUC) of oral microbial markers in the training cohort and validation cohort was 98.85% and 97.23%, respectively. Importantly, the AUC of the biomarker set achieved 92.44% of additional independent validation sets. In addition, EPRs also have their own unique oral community.

Conclusion

This study describes the characterization of the oral microbiome in EP and EPR and demonstrates the potential of the specific microbiome as a non-invasive diagnostic tool for epilepsy.

Unveiling the influence of daily dietary patterns on brain cortical structure: insights from bidirectional Mendelian randomization

Cognitive impairment is a significant concern in aging populations. This study utilized Mendelian randomization analysis to explore the impact of dietary habits and macro-nutrients on cortical structure. A bidirectional Mendelian randomization approach was employed, incorporating large-scale genetic data on dietary habits and brain cortical structure. The results did not reveal significant causal relationships between dietary factors and overall cortical structure and thickness. However, specific dietary factors showed associations with cortical structure in certain regions. For instance, fat intake affected six cortical regions, while milk, protein, fruits, and water were associated with changes in specific regions. Reverse analysis suggested that cortical thickness influenced the consumption of alcohol, carbohydrates, coffee, and fish. These findings contribute to understanding the potential mechanisms underlying the role of dietary factors in cognitive function changes and provide evidence supporting the existence of the gut-brain axis.

Does the ketogenic diet improve neurological disorders by influencing gut microbiota? A systematic review

BACKGROUND

The aim of this systematic review is to evaluate the changes in gut microbiota (GM) induced by the Ketogenic Diets (KD) as a potential underlying mechanism in the improvement of neurological diseases.

METHODS

A comprehensive search was conducted on three electronic databases, including PubMed/Medline, Web of Science, and Scopus until December 2022. The inclusion criteria were studies that described any changes in GM after consuming KD in neurological patients. Full text of studies such as clinical trials and cohorts were added. The quality assessment of cohort studies was conducted using the Newcastle-Ottawa Quality Assessment Scale and for the clinical trials using the Cochrane Collaboration tool. The search, screening, and data extraction were performed by two researchers independently.

RESULTS

Thirteen studies examining the effects of the KD on the GM in neurological patients were included. Studies have shown that KD improves clinical outcomes by reducing disease severity and recurrence rates. An increase in Proteobacteria phylum, Escherichia, Bacteroides, Prevotella, Faecalibacterium, Lachnospira, Agaricus, and Mrakia genera and a reduction in Firmicutes, and Actinobacteria phyla, Eubacterium, Cronobacter, Saccharomyces, Claviceps, Akkermansia and Dialister genera were reported after KD. Studies showed a reduction in concentrations of fecal short-chain fatty acids and branched-chain fatty acids and an increase in beta Hydroxybutyrate, trimethylamine N-oxide, and N-acetylserotonin levels after KD.

CONCLUSION

The KD prescribed in neurological patients has effectively altered the GM composition and GM-derived metabolites.

Revisiting the concept of drug-resistant epilepsy: A TASK1 report of the ILAE/AES Joint Translational Task Force

Despite progress in the development of anti-seizure medications (ASMs), one third of people with epilepsy have drug-resistant epilepsy (DRE). The working definition of DRE, proposed by the International League Against Epilepsy (ILAE) in 2010, helped identify individuals who might benefit from presurgical evaluation early on. As the incidence of DRE remains high, the TASK1 workgroup on DRE of the ILAE/American Epilepsy Society (AES) Joint Translational Task Force discussed the heterogeneity and complexity of its presentation and mechanisms, the confounders in drawing mechanistic insights when testing treatment responses, and barriers in modeling DRE across the lifespan and translating across species. We propose that it is necessary to revisit the current definition of DRE, in order to transform the preclinical and clinical research of mechanisms and biomarkers, to identify novel, effective, precise, pharmacologic treatments, allowing for earlier recognition of drug resistance and individualized therapies.

Electrophysiological, histopathological, and biochemical evaluation of the protective effect of probiotic supplementation against pentylenetetrazole-induced seizures in rats

BACKGROUND AND PURPOSE

Research on the relationship between the gut microbiome and epilepsy is accumulating. The present study was conducted to evaluate the effect of probiotic supplementation on pentylenetetrazole (PTZ)-induced seizures in rats.

METHODS

Twenty-one adult male Wistar albino rats were included. The animals were divided into three groups of seven rats. Group 1 was a control group, whereas Group 2 rats received PTZ treatment and Group 3 rats had PTZ+PB (probiotic) treatment. For 6 weeks, Groups 1 and 2 were given saline (1 ml), whereas Group 3 had probiotic supplement. In the 5th week, tripolar electrodes were attached to the rats. Electrophysiological, behavioral, biochemical, and immunohistochemical evaluations were performed in the 6 weeks after the treatment.

RESULTS

PB treatment significantly reduced seizures. In the PTZ group, expression levels of brain-derived neurotrophic factor, nerve growth factor (NGF), and Sox2 (SRY sex-determining region Y-box 2) in rat brains decreased significantly compared to the control group, whereas the expression levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), total oxidant status (TOS), and nitric oxide (NO) levels increased. In the PTZ+PB group, NGF expression increased significantly compared to the PTZ group, whereas TNF-α, IL-6, TOS, and NO levels decreased. In histopathological examination, an abundance of necrotic neurons was notable in the PTZ group, which was less in the PTZ+PB group. In addition, body weight of the group supplemented with probiotics decreased after the treatment.

CONCLUSIONS

Our results suggest that probiotic supplementation may alleviate seizure severity and exert neuroprotective effects by reducing neuroinflammation and oxidative stress and altering the expression of neurotrophins in epileptogenic brains.

The microbiome-gut-brain axis in epilepsy: pharmacotherapeutic target from bench evidence for potential bedside applications

The gut-brain axis augments the bidirectional communication between the gut and brain and modulates gut homeostasis and the central nervous system through the hypothalamic-pituitary-adrenal axis, enteroendocrine system, neuroendocrine system, inflammatory and immune pathways. Preclinical and clinical reports showed that gut dysbiosis might play a major regulatory role in neurological diseases such as epilepsy, Parkinson's, multiple sclerosis, and Alzheimer's disease. Epilepsy is a chronic neurological disease that causes recurrent and unprovoked seizures, and numerous risk factors are implicated in developing epilepsy. Advanced consideration of the gut-microbiota-brain axis can reduce ambiguity about epilepsy pathology, antiepileptic drugs, and effective therapeutic targets. Gut microbiota sequencing analysis reported that the level of Proteobacteria, Verrucomicrobia, Fusobacteria, and Firmicutes was increased and the level of Actinobacteria and Bacteroidetes was decreased in epilepsy patients. Clinical and preclinical studies also indicated that probiotics, ketogenic diet, faecal microbiota transplantation, and antibiotics can improve gut dysbiosis and alleviate seizure by enhancing the abundance of healthy biota. This study aims to give an overview of the connection between gut microbiota, and epilepsy, how gut microbiome changes may cause epilepsy, and whether gut microbiome restoration could be used as a treatment for epilepsy.

Ketogenic Diet Has Moderate Effects on the Fecal Microbiota of Wild-Type Mice

The ketogenic diet (KD) is a high-fat, low-carbohydrate diet that has been reported to have neuroprotective effects. The health effects of KD might be linked to an altered gut microbiome, which plays a major role in host health, leading to neuroprotective effects via the gut-brain axis. However, results from different studies, most often based on the 16S rRNA gene and metagenome sequencing, have been inconsistent. In this study, we assessed the effect of a 4-week KD compared to a western diet (WD) on the colonic microbiome of female C57Bl/6J mice by analyzing fecal samples using fluorescence in situ hybridization. Our results showed distinct changes in the total number of gut bacteria following the 4-week KD, in addition to changes in the composition of the microbiome. KD-fed mice showed higher absolute numbers of Actinobacteria (especially Bifidobacteria spp.) and lower absolute levels of Proteobacteria, often linked to gut inflammation, in comparison with WD-fed mice. Furthermore, an increased abundance of the typically rare genus Atopobium was observed. These changes may indicate the possible anti-inflammatory effects of the KD. However, since the overall changes in the microbiota seem low, the KD effects might be linked to the differential abundance of only a few key genera in mice.

Integrated Macrogenomics and Metabolomics Explore Alterations and Correlation between Gut Microbiota and Serum Metabolites in Adult Epileptic Patients: A Pilot Study

Epilepsy (EP) is a complex brain disorder showing a lot of unknows reasons. Recent studies showed that gut microbiota can influence epilepsy via the brain-gut axis. Nevertheless, the mechanism by which gut microbiota affects adult epilepsy still remains unclear. In this study, fecal and serum samples were obtained from patients with epilepsy and normal controls. Using an integrated analysis, sequencing was performed by macrogenomics and high-throughput targeted metabolomics with various bioinformatics approaches. The macrogenomic sequencing revealed significant changes in microbial structure in patients suffering from epilepsy. For example, at the phylum level, the relative abundance of Actinobacteria, Bacteroidetes and Proteobacteria showed an increase in the patients with epilepsy, whereas that of Firmicutes decreased. In addition, the patients with epilepsy had significantly differential metabolite profiles compared to normal controls, and five clusters with 21 metabolites, mainly containing the upregulation of some fatty acids and downregulation of some amino acids. Tryptophan (AUC = 91.81, p < 0.0001), kynurenine (AUC = 79.09, p < 0.01) and 7Z,10Z,13Z,16Z-Docosatetraenoic acid (AUC = 80.95, p < 0.01) may be used as potential diagnostic markers for epilepsy. Differential serum metabolites have effects on tryptophan metabolism, iron death and other pathways. Furthermore, a multiomic joint analysis observed a statistically significant correlation between the differential flora and the differential serum metabolites. In our findings, a macrogenomic analysis revealed the presence of dysregulated intestinal flora species and function in adult epileptic patients. Deeper metabolomic analyses revealed differences in serum metabolites between patients with epilepsy and healthy populations. Meanwhile, the multiomic combination showed connection between the gut microbes and circulating metabolites in the EP patients, which may be potential therapeutic targets.

Cholecystectomy Significantly Alters Gut Microbiota Homeostasis and Metabolic Profiles: A Cross-Sectional Study

Cholecystectomy (CCE) is a standard clinical treatment for conditions like gallstones and cholecystitis. However, its link to post-CCE syndrome, colorectal cancer, and nonalcoholic fatty liver disease has raised concerns. Additionally, studies have demonstrated the disruptive effects of CCE on gut microbiota homeostasis and bile acid (BA) metabolism. Considering the role of gut microbiota in regulating host metabolic and immune pathways, the use of dietary and probiotic intervention strategies to maintain a stable gut ecosystem after CCE could potentially reduce associated disease risks. Inter-study variations have made it challenging to identify consistent gut microbiota patterns after CCE, a prerequisite for targeted interventions. In this study, we first meta-analyzed 218 raw 16S rRNA gene sequencing datasets to determine consistent patterns of structural and functional changes in the gut microbiota after CCE. Our results revealed significant alterations in the gut microbiota's structure and function due to CCE. Furthermore, we identified characteristic gut microbiota changes associated with CCE by constructing a random model classifier. In the validation cohort, this classifier achieved an area under the receiver operating characteristic curve (AUC) of 0.713 and 0.683 when distinguishing between the microbiota of the CCE and healthy groups at the family and genus levels, respectively. Further, fecal metabolomics analysis demonstrated that CCE also substantially modified the metabolic profile, including decreased fecal short-chain fatty acid levels and disrupted BA metabolism. Importantly, dietary patterns, particularly excessive fat and total energy intake, influenced gut microbiota and metabolic profile changes post-CCE. These dietary habits were associated with further enrichment of the microbiota related to BA metabolism and increased levels of intestinal inflammation after CCE. In conclusion, our study identified specific alterations in gut microbiota homeostasis and metabolic profiles associated with CCE. It also revealed a potential link between dietary patterns and gut microbiota changes following CCE. Our study provides a theoretical basis for modulating gut microbiota homeostasis after CCE using long-term dietary strategies and probiotic interventions.

Analysis of metabolites in human gut: illuminating the design of gut-targeted drugs

Gut-targeted drugs provide a new drug modality besides that of oral, systemic molecules, that could tap into the growing knowledge of gut metabolites of bacterial or host origin and their involvement in biological processes and health through their interaction with gut targets (bacterial or host, too). Understanding the properties of gut metabolites can provide guidance for the design of gut-targeted drugs. In the present work we analyze a large set of gut metabolites, both shared with serum or present only in gut, and compare them with oral systemic drugs. We find patterns specific for these two subsets of metabolites that could be used to design drugs targeting the gut. In addition, we develop and openly share a Super Learner model to predict gut permanence, in order to aid in the design of molecules with appropriate profiles to remain in the gut, resulting in molecules with putatively reduced secondary effects and better pharmacokinetics.

Topiramate alters the gut microbiome to aid in its anti-seizure effect

Introduction

There is a growing interest in the role of the gut microbiota in epilepsy, however, it is unclear if anti-seizure medications (ASMs) play a role in the gut-brain axis. To test this, we investigated the impact of the ASM topiramate on the gut microbiome of mice.

Methods

C57BL/6J mice were administered topiramate in their drinking water for 5 weeks. 16S ribosomal RNA gene sequencing was performed on fecal samples collected at 5 weeks. Analysis of alpha diversity, beta diversity, and differential abundance were performed. Cecal contents were analyzed for short-chain fatty acids (SCFAs) composition. Pentylenetetrazol (PTZ)-kindling was performed in saline, topiramate, Lactobacillus johnsonii, and topiramate and Lactobacillus johnsonii treated mice. Mice received PTZ injection every other day for a total of twelve injections, seizure activity was video monitored for 30 minutes and scored.

Results and discussion

Our study revealed that topiramate ingestion significantly increased Lactobacillus johnsonii in the gut microbiome of naïve mice. Treatment with topiramate and Lactobacillus johnsonii together, but not alone, reduced susceptibility to PTZ-induced seizures. Co-treatment also significantly increased the percent of butyrate and the abundance of butyrate-producing family Lachnospiraceae in the gut, and elevated the GABA/glutamate ratio in the cortex. Our results demonstrate that an ASM can alter the gut microbiome to aid in their anti-seizure effect in vivo and suggest the potential of the probiotic Lactobacillus johnsonii as an adjunct therapy with topiramate in reducing seizure susceptibility.

Combination of Walnut Peptide and Casein Peptide alleviates anxiety and improves memory in anxiety mices

Introduction

Anxiety disorders continue to prevail as the most prevalent cluster of mental disorders following the COVID-19 pandemic, exhibiting substantial detrimental effects on individuals' overall well-being and functioning. Even after a search spanning over a decade for novel anxiolytic compounds, none have been approved, resulting in the current anxiolytic medications being effective only for a specific subset of patients. Consequently, researchers are investigating everyday nutrients as potential alternatives to conventional medicines. Our prior study analyzed the antianxiety and memory-enhancing properties of the combination of Walnut Peptide (WP) and Casein Peptide (CP) in zebrafish.

Methods and Results

Based on this work, our current research further validates their effects in mice models exhibiting elevated anxiety levels through a combination of gavage oral administration. Our results demonstrated that at 170 + 300 mg human dose, the WP + CP combination significantly improved performances in relevant behavioral assessments related to anxiety and memory. Furthermore, our analysis revealed that the combination restores neurotransmitter dysfunction observed while monitoring Serotonin, gamma-aminobutyric acid (GABA), dopamine (DA), and acetylcholine (ACh) levels. This supplementation also elevated the expression of brain-derived neurotrophic factor mRNA, indicating protective effects against the neurological stresses of anxiety. Additionally, there were strong correlations among behavioral indicators, BDNF (brain-derived neurotrophic factor), and numerous neurotransmitters.

Conclusion

Hence, our findings propose that the WP + CP combination holds promise as a treatment for anxiety disorder. Besides, supplementary applications are feasible when produced as powdered dietary supplements or added to common foods like powder, yogurt, or milk.

Complementarity between Microbiome and Immunity May Account for the Potentiating Effect of Quercetin on the Antitumor Action of Cyclophosphamide in a Triple-Negative Breast Cancer Model

Immunotherapy targeting program cell death protein 1 (PD-1) in addition to chemotherapy has improved the survival of triple-negative breast cancer (TNBC) patients. However, the development of resistance and toxicity remain significant problems. Using the translationally relevant 4T1 mouse model of TNBC, we report here that dietary administration of the phytochemical quercetin enhanced the antitumor action of Cyclophosphamide, a cytotoxic drug with significant immunogenic effects that is part of the combination chemotherapy used in TNBC. We observed that quercetin favorably modified the host fecal microbiome by enriching species such as Akkermansia muciniphilia, which has been shown to improve response to anti-PD-1 therapy. We also show that quercetin and, to a greater extent, Cyclophosphamide increased the systemic frequency of T cells and NK cells. In addition, Cyclophosphamide alone and in combination with quercetin reduced the frequency of Treg, which is consistent with an antitumor immune response. On the other hand, Cyclophosphamide did not significantly alter the host microbiome, suggesting complementarity between microbiome- and immune-mediated mechanisms in potentiating the antitumor action of Cyclophosphamide by quercetin. Overall, these results support the potential for microbiota-centered dietary intervention to overcome resistance to chemoimmunotherapy in TNBC.

Metagenomics-based inference of microbial metabolism towards neuroactive amino acids and the response to antibiotics in piglet colon

Gut-derived neuroactive metabolites from amino acids perform a broad range of physiological roles in the body. However, the interaction between microbiota and epithelium in the metabolism of amino acids with neuroactive properties remains unclear in the colon of piglets. To investigate the microbial and epithelial metabolism, metagenomics and mucosal metabolomics were performed using colonic samples from 12 ileum-canulated piglets subjected to a 25-day infusion with saline or antibiotics. We categorized 23 metabolites derived from the metabolism of tryptophan, glutamate, and tyrosine, known as precursors of neuroactive metabolites. Microbial enzymes involved in the kynurenine synthesis via arylformamidase, 4-aminobutyric acid (GABA) synthesis via putrescine aminotransferase, and tyramine synthesis via tyrosine decarboxylase were identified in Clostridiales bacterium, uncultured Blautia sp., and Methanobrevibacter wolinii, respectively. Antibiotics significantly affected the microbiota involved in tryptophan-kynurenine and glutamate-GABA metabolism. An increase in the relative abundance of putrescine aminotransferase and Blautia sp. correlated positively with an increase in luminal GABA concentration. Overall, our findings provide new insights into the microbial ability to metabolize key amino acids that are precursors of neuroactive metabolites.

Assessing the association between supplemented puppyhood dietary fat sources and owner-reported epilepsy in adulthood, among Finnish companion dogs

Introduction

Epilepsy is a serious and common neurological condition in dogs, despite the wide number of antiepileptic drugs available, in approximately one third of the patients, epilepsy remains unsatisfactorily controlled. We aim to analyze whether feeding dietary fat sources during puppyhood was associated with canine epilepsy in adulthood.

Methods

A nested case-control study was compiled from the validated DogRisk food frequency questionnaire (DogRisk FFQ). DogRisk FFQ collected feeding, disease, and background data about the dog. The study sample consisted of 108 owner-reported epileptic cases and 397 non-epileptic controls. Each case was matched with up to four controls for the key confounding factors of sex, breed, and age. We analyzed associations between feeding as a puppy and owner-reported epilepsy as an adult dog using Cox regression. We tested 55 different food variables.

Results

We found that feeding fish fat from dietary sources at least once a week during puppyhood was inversely associated with epilepsy in later life in the unadjusted analysis [OR 0.46 (95% CI 0.25-0.83), p=0.01], while when adjusting for keeping conditions and dog characteristics the association was [OR 0.45 (95% CI 0.23-0.88), p=0.02]. When adjusted for keeping conditions, dog characteristics, and other feeding factors, the association was of similar magnitude but not significance [OR 0.56 (95% CI 0.27-1.15), p=0.12].

Discussion

The study indicates possible protective associations of feeding the dog with dietary sources of fish fat against epilepsy, although the result could be confounded by other feeding factors. Findings are compatible with current knowledge regarding the role of omega-3 fatty acids and ketogenic diet, a low carbohydrate, high fat diet as supportive treatments of epilepsy. As our findings are based on observations, we suggest the possibility of causality but do not prove it. Dietary intervention studies should now be conducted to confirm our findings.

Ketogenic diet for mood disorders from animal models to clinical application

Mood disorders such as major depressive disorder (MDD) and bipolar disorder (BD) are often resistant to current pharmacological treatment. Therefore, various alternative therapeutic approaches including diets are, therefore, under investigation. Ketogenic diet (KD) is effective for treatment-resistant epilepsy and metabolic diseases, however, only a few clinical studies suggest its beneficial effect also for mental disorders. Animal models are a useful tool to uncover the underlying mechanisms of therapeutic effects. Women have a twice-higher prevalence of mood disorders but very little is known about sex differences in nutritional psychiatry. In this review, we aim to summarize current knowledge of the sex-specific effects of KD in mood disorders. Ketone bodies improve mitochondrial functions and suppress oxidative stress, inducing neuroprotective and anti-inflammatory effects which are both beneficial for mental health. Limited data also suggest KD-induced improvement of monoaminergic circuits and hypothalamus-pituitary-adrenal axis-the key pathophysiological pathways of mood disorders. Gut microbiome is an important mediator of the beneficial and detrimental effects of diet on brain functioning and mental health. Gut microbiota composition is affected in mood disorders but its role in the therapeutic effects of different diets, including KD, remains poorly understood. Still little is known about sex differences in the effects of KD on mental health as well as on metabolism and body weight. Some animal studies used both sexes but did not find differences in behavior, body weight loss or gut microbiota composition. More studies, both on a preclinical and clinical level, are needed to better understand sex-specific effects of KD on mental health.

Recent Review on Selected Xenobiotics and Their Impacts on Gut Microbiome and Metabolome

As it is well known, the gut is one of the primary sites in any host for xenobiotics, and the many microbial metabolites responsible for the interactions between the gut microbiome and the host. However, there is a growing concern about the negative impacts on human health induced by toxic xenobiotics. Metabolomics, broadly including lipidomics, is an emerging approach to studying thousands of metabolites in parallel. In this review, we summarized recent advancements in mass spectrometry (MS) technologies in metabolomics. In addition, we reviewed recent applications of MS-based metabolomics for the investigation of toxic effects of xenobiotics on microbial and host metabolism. It was demonstrated that metabolomics, gut microbiome profiling, and their combination have a high potential to identify metabolic and microbial markers of xenobiotic exposure and determine its mechanism. Further, there is increasing evidence supporting that reprogramming the gut microbiome could be a promising approach to the intervention of xenobiotic toxicity.

Identifying Novel Drug Targets for Epilepsy Through a Brain Transcriptome-Wide Association Study and Protein-Wide Association Study with Chemical-Gene-Interaction Analysis

Epilepsy is a severe neurological condition affecting 50-65 million individuals worldwide that can lead to brain damage. Nevertheless, the etiology of epilepsy remains poorly understood. Meta-analyses of genome-wide association studies involving 15,212 epilepsy cases and 29,677 controls of the ILAE Consortium cohort were used to conduct transcriptome-wide association studies (TWAS) and protein-wide association studies (PWAS). Furthermore, a protein-protein interaction (PPI) network was generated using the STRING database, and significant epilepsy-susceptible genes were verified using chip data. Chemical-related gene set enrichment analysis (CGSEA) was performed to determine novel drug targets for epilepsy. TWAS analysis identified 21,170 genes, of which 58 were significant (TWASfdr < 0.05) in ten brain regions, and 16 differentially expressed genes were verified based on mRNA expression profiles. The PWAS identified 2249 genes, of which 2 were significant (PWASfdr < 0.05). Through chemical-gene set enrichment analysis, 287 environmental chemicals associated with epilepsy were identified. We identified five significant genes (WIPF1, IQSEC1, JAM2, ICAM3, and ZNF143) that had causal relationships with epilepsy. CGSEA identified 159 chemicals that were significantly correlated with epilepsy (Pcgsea < 0.05), such as pentobarbital, ketone bodies, and polychlorinated biphenyl. In summary, we performed TWAS, PWAS (for genetic factors), and CGSEA (for environmental factors) analyses and identified several epilepsy-associated genes and chemicals. The results of this study will contribute to our understanding of genetic and environmental factors for epilepsy and may predict novel drug targets.

Effects of probiotics on GABA/glutamate and oxidative stress in PTZ- induced acute seizure model in rats

Studies conducted in recent years have indicated a relationship between epilepsy and gut microbiota. Ion channels, excitatory/inhibitory balance and regulatory systems play a role in the pathophysiology of epilepsy. In addition, gut dysbiosis is also involved in the pathophysiology of epilepsy. This research investigated the impacts of probiotic mixture on epileptic seizures, Gamma aminobutyric acid (GABA), glutamate, and TAS and TOS levels in hippocampal tissue in the PTZ-induced acute seizure model in rats. Four groups were formed with male Wistar albino rats. The first and second groups were given 1 ml/day saline solution, and the other groups were given 0.05 mg/1 ml/day vehicle or 109cfu/1 ml/day probiotic supplementation, respectively via gavage for 21 days. A single-dose PTZ (45 mg/kg) was administered to induce seizure. The stages of seizure were analyzed according to the Racine scale. While ELISA was used to determine GABA and glutamate levels in the hippocampus, an automated colorimetric method was utilized to measure oxidant/antioxidant biomarkers. It was found that by delaying the first myoclonic jerk (FMJ), and the onset of the generalized tonic-clonic seizures, the probiotic mixture demonstrated anticonvulsant effects against seizures. The probiotic mixture was found to increase the inhibitory neurotransmitter GABA. It was also found to decrease TOS levels and increase TAS concentration. The findings of this study showed that probiotic mixture reduced oxidative stress with its positive effects against PTZ-induced epileptic seizures. Further studies are needed to reveal potentially related mechanisms.

Intermittent dietary carbohydrate restriction versus calorie restriction and cardiometabolic profiles: A randomized trial

OBJECTIVE

The aim of this study was to investigate the effectiveness of an intermittent low-carbohydrate diet (ILCD) versus calorie restriction (ICR) in young populations and potential mechanisms.

METHODS

Thirty-four participants aged 9 to 30 years with cardiometabolic risk were randomized to receive a self-administered 2-week ILCD (carbohydrate intake ≤ 50 g/d on seven nonconsecutive days) or ICR (500-600 kcal/d for two consecutive days per week). Differences in changes in obesity measures, glycemic and lipid profiles, gut microbiota composition, and three serum biomarkers were compared.

RESULTS

The ILCD and ICR similarly reduced body weight, waist circumference, fasting glucose, insulin, postprandial glucose variation, monocyte chemoattractant protein-1, free fatty acid, and fibroblast growth factor 21, whereas ILCD produced significantly different alterations in the following outcomes compared with ICR: greater increases in low-density lipoprotein cholesterol and total cholesterol (-0.36 mmol/L, 95% CI: -0.68 to -0.04; -0.40 mmol/L, 95% CI: -0.73 to -0.06) and greater decrease in triglyceride (0.20 mmol/L, 95% CI: 0.04 to 0.37). Actinobacteria and Bifidobacterium reduced after ILCD but not ICR; and the reductions strongly correlated with changes in fasting glucose (both r = 0.84) and low-density lipoprotein cholesterol (r = -0.81 and -0.72).

CONCLUSIONS

This study found no evidence of differences in changes from baseline in obesity measures, glucose regulation, and inflammation between ILCD and ICR, despite trends in reduction in those parameters. However, there seemed to be some differences in responses in lipids and gut microbiota.

The Role of Diet and Gut Microbiota Interactions in Metabolic Homeostasis

Diet is a pivotal determinant in shaping the structure and function of resident microorganisms in the gut through different food components, nutritive proportion, and calories. The effects of diet on host metabolism and physiology can be mediated through the gut microbiota. Gut microbiota-derived metabolites have been shown to regulate glucose and lipid metabolism, energy consumption, and the immune system. On the other hand, emerging evidence indicates that baseline gut microbiota could predict the efficacy of diet intervention, highlighting gut microbiota can be harnessed as a biomarker in personalized nutrition. In this review, the alterations of gut microbiota in different dietary components and dietary patterns, and the potential mechanisms in the diet-microbiota crosstalk are summarized to understand the interactions of diet and gut microbiota on the impact of metabolic homeostasis.

Short- and long-term effects of very low- and low-calorie ketogenic diets on metabolism and cardiometabolic risk factors: a narrative review

Worldwide obesity and cardiovascular diseases have encouraged the adoption of new and efficient dietary strategies. Among various proposed diets, ketogenic diets, both the very-low-calorie ketogenic diet (VLCKD) and the low-calorie ketogenic diet (LCKD), have been suggested in recent years as an effective nutritional approach for obesity management. The VLCKD and the LCKD are characterized by a low carbohydrate content (<50 g/day), 1-1.5 g of protein/kg of ideal body weight, less than 20-30 g of lipids, and a daily intake of about 800 calories for VLCKD and about 1200-1400 calories for LCKD. The purpose of our narrative review is to offer an overview of the most impactful studies in the scientific literature regarding VLCKD and LCKD to discuss their short- and long-term effects (less than 12 months and more than 12 months respectively) on weight loss, metabolic and cardiovascular aspects. Articles we focused on were cohort studies, case-control studies, cross-sectional studies, randomized controlled trials, and meta-analyses. Results indicate that VLCKD and LCKD could be helpful to ameliorate metabolic and cardiovascular risk factors such as weight loss, glucose, and cholesterol levels, both in the short and long term. Further research in this area may include more randomized controlled trials to gather more data.

Effects of a Very-Low-Calorie Ketogenic Diet on the Fecal and Urinary Volatilome in an Obese Patient Cohort: A Preliminary Investigation

Several recent studies deepened the strong connection between gut microbiota and obesity. The effectiveness of the very-low-calorie ketogenic diet (VLCKD) has been measured in terms of positive impact on the host homeostasis, but little is known of the modification exerted on the intestinal metabolome. To inspect this complex relationship, we analyzed both fecal and urinary metabolome in terms of volatile organic compounds (VOCs) by the GC-MS method in 25 obese patients that were under VLCKD for eight weeks. Partial least square discriminant analysis evidenced specific urinary and fecal metabolites whose profile can be considered a signature of a partial restore toward the host eubiosis. Specifically, among various keystone VOCs, the decreased concentration of four statistically significant fecal esters (i.e., propanoic acid pentyl ester, butanoic acid hexyl ester, butanoic acid pentyl ester, and pentanoic acid butyl ester) supports the positive effect of VLCKD treatment. Our pilot study results suggest a potential positive effect of VLCKD intervention affecting fecal and urinary volatilome profiles from obese patients. Meta-omics techniques including the study of genes and transcripts will help in developing new interventions useful in preventing or treating obesity and its associated health problems.

The Influence of Ketogenic Diet on Gut Microbiota: Potential Benefits, Risks and Indications

The ketogenic diet (KD) restricts carbohydrate consumption, leading to an increase in ketone bodies, such as acetoacetate, β-hydroxybutyrate, and acetone, which are utilized as energy substrates. This dietary approach impacts several biochemical processes, resulting in improved clinical management of various disorders, particularly in childhood. However, the exact mechanisms underlying the efficacy of KD remain unclear. Interestingly, KD may also impact the gut microbiota, which plays a pivotal role in metabolism, nutrition, and the development of the immune and nervous systems. KD has gained popularity for its potential benefits in weight loss, blood sugar control, and certain neurological conditions. This narrative review sums up KD-related studies published over 30 years. While short-term studies have provided valuable insights into the effects of KD on the gut microbiota, persistent uncertainties surround its long-term efficacy and potential for inducing dysbiosis. The significant influence of KD on epigenetic mechanisms, intracellular pathways, and gut microbial composition underscores its potential as a therapeutic choice. However, a judicious consideration of the potential risks associated with the strict adherence to a low-carbohydrate, high-fat, and high-protein regimen over prolonged periods is imperative. As KDs gain popularity among the adolescent and young adult demographic for weight management, it becomes imperative to undertake additional research to comprehensively assess their impact on nutritional status and gut microbiota, ensuring a holistic and sustainable approach to medical nutrition.

The Role of Artificial Intelligence in Deciphering Diet-Disease Relationships: Case Studies

Modernization of society from a rural, hunter-gatherer setting into an urban and industrial habitat, with the associated dietary changes, has led to an increased prevalence of cardiometabolic and additional noncommunicable diseases, such as cancer, inflammatory bowel disease, and neurodegenerative and autoimmune disorders. However, while dietary sciences have been rapidly evolving to meet these challenges, validation and translation of experimental results into clinical practice remain limited for multiple reasons, including inherent ethnic, gender, and cultural interindividual variability, among other methodological, dietary reporting-related, and analytical issues. Recently, large clinical cohorts with artificial intelligence analytics have introduced new precision and personalized nutrition concepts that enable one to successfully bridge these gaps in a real-life setting. In this review, we highlight selected examples of case studies at the intersection between diet-disease research and artificial intelligence. We discuss their potential and challenges and offer an outlook toward the transformation of dietary sciences into individualized clinical translation.

Fecal microbiota transplantation alleviates experimental colitis through the Toll-like receptor 4 signaling pathway

BACKGROUND

Fecal microbiota transplantation (FMT) has shown promising therapeutic effects on mice with experimental colitis and patients with ulcerative colitis (UC). FMT modulates the Toll-like receptor 4 (TLR4) signaling pathway to treat some other diseases. However, it remains unknown whether this modulation is also involved in the treatment of UC.

AIM

To clarify the necessity of TLR4 signaling pathway in FMT on dextran sodium sulphate (DSS)-induced mice and explain the mechanism of FMT on UC, through association analysis of gut microbiota with colon transcriptome in mice.

METHODS

A mouse colitis model was constructed with wild-type (WT) and TLR4-knockout (KO) mice. Fecal microbiota was transplanted by gavage. Colon inflammation severity was measured by disease activity index (DAI) scoring and hematoxylin and eosin staining. Gut microbiota structure was analyzed through 16S ribosomal RNA sequencing. Gene expression in the mouse colon was obtained by transcriptome sequencing.

RESULTS

The KO (DSS + Water) and KO (DSS + FMT) groups displayed indistinguishable body weight loss, colon length, DAI score, and histology score, which showed that FMT could not inhibit the disease in KO mice. In mice treated with FMT, the relative abundance of Akkermansia decreased, and Lactobacillus became dominant. In particular, compared with those in WT mice, the scores of DAI and colon histology were clearly decreased in the KO-DSS group. Microbiota structure showed a significant difference between KO and WT mice. Akkermansia were the dominant genus in healthy KO mice. The ineffectiveness of FMT in KO mice was related to the decreased abundance of Akkermansia. Gene Ontology enrichment analysis showed that differentially expressed genes between each group were mainly involved in cytoplasmic translation and cellular response to DNA damage stimulus. The top nine genes correlating with Akkermansia included Aqp4, Clca4a, Dpm3, Fau, Mcrip1, Meis3, Nupr1 L, Pank3, and Rps13 (|R| > 0.9, P < 0.01).

CONCLUSION

FMT may ameliorate DSS-induced colitis by regulating the TLR4 signaling pathway. TLR4 modulates the composition of gut microbiota and the expression of related genes to ameliorate colitis and maintain the stability of the intestinal environment. Akkermansia bear great therapeutic potential for colitis.

Impact of active lifestyle on the primary school children saliva microbiota composition

The aim of the study was to evaluate the effects of Active or Sedentary lifestyle on saliva microbiota composition in Italian schoolchildren.

Methods

Male (114) and female children (8-10 years) belonging to five primary schools in the neighborhoods of Turin were classified as active (A) or sedentary (S) based on PAQ-C-It questionnaire. PCR amplification of salivary DNA targeted the hypervariable V3-V4 regions of the 16S rRNA bacterial genes. DADA2 workflow was used to infer the Amplicon Sequence Variants and the taxonomic assignments; the beta-diversity was obtained by PCoA with the UniFrac method; LEfSe algorithm, threshold at 5%, and Log LDA cutoff at ±0.5 were used to identify differently abundant species in A compared to S saliva sample. Daily food intake was assessed by 3-Days food record. The metabolic potential of microbial communities was assessed by PICRUSt.

Results

No significant differences were found in individual's gender distribution (p = 0.411), anthropometry, BMI (p > 0.05), and all diet composition between A and S groups (p > 0.05). Eight species were differently abundant: Prevotella nigrescens (LDA score = -3.76; FDR = 1.5×10-03), Collinsella aerofaciens (LDA score = -3.17; FDR = 7.45×10-03), Simonsiella muelleri (LDA score = -2.96; FDR = 2.76×10-05), Parabacteroides merdae (LDA score = -2.43; FDR = 1.3×10-02) are enriched in the A group; Gemella parahaemolysans, Prevotella aurantiaca (LDA score = -3.9; FDR = 5.27×10-04), Prevotella pallens (LDA score = 4.23; FDR = 1.93×10-02), Neisseria mucosa (LDA score = 4.43; FDR = 1.31×10-02; LDA score = 2.94; FDR = 7.45×10-03) are enriched in the S group. A prevalence of superpathway of fatty acid biosynthesis initiation (E. coli) and catechol degradation II (meta-cleavage pathway) was found in saliva from A compared to S children.

Conclusion

Our results showed that active children had an enrichment of species and genera mainly associated with a healthier profile. By contrast, the genera and the species enriched in the sedentary group could be linked to human diseases.

A Novel Genetic Variant in MBD5 Associated with Severe Epilepsy and Intellectual Disability: Potential Implications on Neural Primary Cilia

Disruptions in the MBD5 gene have been linked with an array of clinical features such as global developmental delay, intellectual disability, autistic-like symptoms, and seizures, through unclear mechanisms. MBD5 haploinsufficiency has been associated with the disruption of primary cilium-related processes during early cortical development, and this has been reported in many neurodevelopmental disorders. In this study, we describe the clinical history of a 12-year-old child harboring a novel MBD5 rare variant and presenting psychomotor delay and seizures. To investigate the impact of MBD5 haploinsufficiency on neural primary cilia, we established a novel patient-derived cell line and used CRISPR-Cas9 technology to create an isogenic control. The patient-derived neural progenitor cells revealed a decrease in the length of primary cilia and in the total number of ciliated cells. This study paves the way to understanding the impact of MBD5 haploinsufficiency in brain development through its potential impact on neural primary cilia.

Intermittent vs continuous ketogenic diet: Impact on seizures, gut microbiota, and mitochondrial metabolism

We have shown previously that the ketogenic diet (KD) is effective in reducing seizures associated with infantile spasms syndrome (ISS) and that this benefit is related to alterations in the gut microbiota. However, it remains unclear whether the efficacy of the KD persists after switching to a normal diet. Employing a neonatal rat model of ISS, we tested the hypothesis that the impact of the KD would diminish when switched to a normal diet. Following epilepsy induction, neonatal rats were divided into two groups: continuous KD for 6 days; and a group fed with KD for 3 days and then a normal diet for 3 days. Spasms frequency, mitochondrial bioenergetics in the hippocampus, and fecal microbiota were evaluated as major readouts. We found that the anti-epileptic effect of the KD was reversible, as evidenced by the increased spasms frequency in rats that were switched from the KD to a normal diet. The spasms frequency was correlated inversely with mitochondrial bioenergetic function and a set of gut microbes, including Streptococcus thermophilus and Streptococcus azizii. These findings suggest that the anti-epileptic and metabolic benefits of the KD decline rapidly in concert with gut microbial alterations in the ISS model.

Effects of ketogenic diet on the classification and functional composition of intestinal flora in children with mitochondrial epilepsy

The ketogenic diet (KD) has shown excellent performance in the treatment of refractory epilepsy, but how it works is not yet fully understood. Gut microbiota is associated with various neurological disorders through the brain-gut axis. Different dietary patterns have different effects on the composition and function of gut microbiota. Here, by analyzing fecal samples from some patients with mitochondrial epilepsy before and after KD treatment through 16SrRNA sequencing, we found that KD intervention reduced the abundance of Firmicutes in the patient's gut, while the abundance of Bacteroidota increased in the KD group. LefSe analysis showed that Actinobacteriota, Phascolarctobacterium had significant advantages in the control group, while Bacteroides increased significantly after KD intervention, especially Bacteroides fragilis. Functional analysis showed that there were significant differences in 12 pathways in level 3. These changes suggest that KD can change the composition and diversity of the gut microbiota in patients and affect their function. Changes in specific bacterial groups in the gut may serve as biomarkers for the therapeutic effects of KD on epilepsy.

Ketogenic diet: a potential adjunctive treatment for substance use disorders

Substance use disorders (SUD) can lead to serious health problems, and there is a great interest in developing new treatment methods to alleviate the impact of substance abuse. In recent years, the ketogenic diet (KD) has shown therapeutic benefits as a dietary therapy in a variety of neurological disorders. Recent studies suggest that KD can compensate for the glucose metabolism disorders caused by alcohol use disorder by increasing ketone metabolism, thereby reducing withdrawal symptoms and indicating the therapeutic potential of KD in SUD. Additionally, SUD often accompanies increased sugar intake, involving neural circuits and altered neuroplasticity similar to substance addiction, which may induce cross-sensitization and increased use of other abused substances. Reducing carbohydrate intake through KD may have a positive effect on this. Finally, SUD is often associated with mitochondrial damage, oxidative stress, inflammation, glia dysfunction, and gut microbial disorders, while KD may potentially reverse these abnormalities and serve a therapeutic role. Although there is much indirect evidence that KD has a positive effect on SUD, the small number of relevant studies and the fact that KD leads to side effects such as metabolic abnormalities, increased risk of malnutrition and gastrointestinal symptoms have led to the limitation of KD in the treatment of SUD. Here, we described the organismal disorders caused by SUD and the possible positive effects of KD, aiming to provide potential therapeutic directions for SUD.

Akkermansia muciniphila inhibited the periodontitis caused by Fusobacterium nucleatum

Periodontitis is the most important cause of tooth loss in adults and is closely related to various systemic diseases. Its etiologic factor is plaque biofilm, and the primary treatment modality is plaque control. Studies have confirmed that Fusobacterium nucleatum can cause periodontitis through its virulence factors and copolymerizing effects with other periodontal pathogens, such as the red complex. Inhibiting F. nucleatum is an essential target for preventing periodontitis. The time-consuming and costly traditional periodontal treatment, periodontal scaling, and root planing are a significant burden on individual and public health. Antibiotic use may lead to oral microbial resistance and microbiome imbalance, while probiotics regulate microbial balance. Akkermansia muciniphila is a critical probiotic isolated from the human intestine. It can protect the integrity of the epithelial barrier, regulate and maintain flora homeostasis, improve metabolism, and colonize the oral cavity. Its abundance is inversely correlated with various diseases. We hypothesized that A. muciniphila could inhibit the effects of F. nucleatum and alleviate periodontitis. Bacterial co-culture experiments showed that A. muciniphila could inhibit the expression of the virulence gene of F. nucleatum. After treating gingival epithelial cells (GECs) with F. nucleatum and A. muciniphila, transcriptome sequencing and ELISA experiments on medium supernatant showed that A. muciniphila inhibited the inflammatory effect of F. nucleatum on GECs by inhibiting TLR/MyD88/NF-κB pathway modulation and secretion of inflammatory factors. Finally, animal experiments demonstrated that A. muciniphila could inhibit F. nucleatum-induced periodontitis in BALB/c mice.

Ketogenic-Mimicking Diet as a Therapeutic Modality for Bipolar Disorder: Biomechanistic Rationale and Protocol for a Pilot Clinical Trial

There is growing interest in the investigation of ketogenic diets as a potential therapy for bipolar disorder. The overlapping pharmacotherapies utilized for both bipolar disorder and seizures suggest that a mechanistic overlap may exist between these conditions, with fasting and the ketogenic diet representing the most time-proven therapies for seizure control. Recently, preliminary evidence has begun to emerge supporting a potential role for ketogenic diets in treating bipolar disorder. Notably, some patients may struggle to initiate a strict diet in the midst of a mood episode or significant life stressors. The key question addressed by this pilot clinical trial protocol is if benefits can be achieved with a less restrictive diet, as this would allow such an intervention to be accessible for more patients. Recent development of so-called ketone esters, that once ingested is converted to natural ketone bodies, combined with low glycemic index dietary changes has the potential to mimic two foundational components of therapeutic ketosis: high levels of ketones and minimal spiking of glucose/insulin. This pilot clinical trial protocol thus aims to investigate the effect of a 'ketogenic-mimicking diet' (combining supplementation of ketone esters with a low glycemic index dietary intervention) on neural network stability, mood, and biomarker outcomes in the setting of bipolar disorder. Positive findings obtained via this pilot clinical trial protocol may support future target engagement studies of ketogenic-mimicking diets or related ketogenic interventions. A lack of positive findings, in contrast, may justify a focus on more strict dietary interventions for future research.

Gut Microbiota and its Metabolites: Bridge of Dietary Nutrients and Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive cognitive impairment and neuroinflammation. Recent research has revealed the crucial role of gut microbiota and microbial metabolites in modulating AD. However, the mechanisms by which the microbiome and microbial metabolites affect brain function remain poorly understood. Here, we review the literature on changes in the diversity and composition of the gut microbiome in patients with AD and in animal models of AD. We also discuss the latest progress in understanding the pathways by which the gut microbiota and microbial metabolites from the host or diet regulate AD. By understanding the effects of dietary components on brain function, microbiota composition, and microbial metabolites, we examine the potential for manipulation of the gut microbiota through dietary intervention to delay the progression of AD. Although it is challenging to translate our understanding of microbiome-based approaches to dietary guidelines or clinical therapies, these findings provide an attractive target for promoting brain function.

Characterization and the cholesterol-lowering effect of dietary fiber from fermented black rice (Oryza sativa L.)

Black rice was fermented with Neurospora crassa, after which the dietary fiber (DF) extracted from it was characterized and evaluated for its cholesterol-lowering effect in mice. The findings demonstrated that fermentation increased the level of soluble DF from 17.27% ± 0.12 to 29.69% ± 0.26 and increased the adsorption capacity of DF for water, oil, cholesterol, glucose and sodium cholate. The fermented DF had a more loose and porous structure than that extracted from unfermented rice. Additionally, feeding with DF from the fermented black rice significantly reduced body weight, lowered total cholesterol levels and improved the lipid profile in mice gavaged with a high dose (5 g per kg bw) or a low dose (2.5 g per kg·bw). ELISA showed that the hepatic expression of typical proteins and enzymes that are involved in cholesterol metabolism was regulated by the fermented rice DF, leading to reduced cholesterol production and increased cholesterol clearance. The fermented DF also modified the gut microbiota composition (e.g. Firmicutes reduced and Akkermansia increased), which promoted the production of short-chain fatty acids. In conclusion, fermentation can modify the structure and function of DF in black rice and the fermented dietary fiber has excellent cholesterol lowering effects possibly by cholesterol adsorption, cholesterol metabolism modulation, and intestinal microflora regulation.

Gut Microbiota and Aging: Traditional Chinese Medicine and Modern Medicine

The changing composition of gut microbiota, much like aging, accompanies people throughout their lives, and the inextricable relationship between both has recently attracted extensive attention as well. Modern medical research has revealed that a series of changes in gut microbiota are involved in the aging process of organisms, which may be because gut microbiota modulates aging-related changes related to innate immunity and cognitive function. At present, there is no definite and effective method to delay aging. However, Nobel laureate Tu Youyou's research on artemisinin has inspired researchers to study the importance of Traditional Chinese Medicine (TCM). TCM, as an ancient alternative medicine, has unique advantages in preventive health care and in treating diseases as it already has formed an independent understanding of the aging system. TCM practitioners believe that the mechanism of aging is mainly deficiency, and pathological states such as blood stasis, qi stagnation and phlegm coagulation can exacerbate the process of aging, which involves a series of organs, including the brain, kidney, heart, liver and spleen. Our current understanding of aging has led us to realise that TCM can indeed make some beneficial changes, such as the improvement of cognitive impairment. However, due to the multi-component and multi-target nature of TCM, the exploration of its mechanism of action has become extremely complex. While analysing the relationship between gut microbiota and aging, this review explores the similarities and differences in treatment methods and mechanisms between TCM and Modern Medicine, in order to explore a new approach that combines TCM and Modern Medicine to regulate gut microbiota, improve immunity and delay aging.

Gut microbiota: a new insight into neurological diseases

ABSTRACT

In the last decade, it has become increasingly recognized that a balanced gut microbiota plays an important role in maintaining the health of the host. Numerous clinical and preclinical studies have shown that changes in gut microbiota composition are associated with a variety of neurological diseases, e.g., Parkinson's disease, Alzheimer's disease, and myasthenia gravis. However, the underlying molecular mechanisms are complex and remain unclear. Behavioral phenotypes can be transmitted from humans to animals through gut microbiota transplantation, indicating that the gut microbiota may be an important regulator of neurological diseases. However, further research is required to determine whether animal-based findings can be extended to humans and to elucidate the relevant potential mechanisms by which the gut microbiota regulates neurological diseases. Such investigations may aid in the development of new microbiota-based strategies for diagnosis and treatment and improve the clinical management of neurological disorders. In this review, we describe the dysbiosis of gut microbiota and the corresponding mechanisms in common neurological diseases, and discuss the potential roles that the intestinal microbiome may play in the diagnosis and treatment of neurological disorders.

Ketogenic diet protects MPTP-induced mouse model of Parkinson's disease via altering gut microbiota and metabolites

The ketogenic diet (KD) is a low-carbohydrate, high-fat regime that is protective against neurodegenerative diseases. However, the impact of KD on Parkinson's disease (PD) and its mechanisms remains unclear. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD was fed with KD for 8 weeks. Motor function and dopaminergic neurons were evaluated. Inflammation in the brain, plasma, and colon tissue were also measured. Fecal samples were assessed by 16S rDNA gene sequencing and untargeted metabolomics. We found that KD protected motor dysfunction, dopaminergic neuron loss, and inflammation in an MPTP mouse model of PD. 16S rDNA sequencing revealed that MPTP administration significantly increased Citrobacter, Desulfovibrio, and Ruminococcus, and decreased Dubosiella, whereas KD treatment reversed the dysbiosis. Meanwhile, KD regulated the MPTP-induced histamine, N-acetylputrescine, d-aspartic acid, and other metabolites. Fecal microbiota transplantation using feces from the KD-treated mice attenuated the motor function impairment and dopaminergic neuron loss in antibiotic-pretreated PD mice. Our current study demonstrates that KD played a neuroprotective role in the MPTP mouse model of PD through the diet-gut microbiota-brain axis, which may involve inflammation in the brain and colon. However, future research is warranted to explore the explicit anti-inflammatory mechanisms of the gut-brain axis in PD models fed with KD.

Diets, Gut Microbiota and Metabolites

The gut microbiota refers to the gross collection of microorganisms, estimated trillions of them, which reside within the gut and play crucial roles in the absorption and digestion of dietary nutrients. In the past decades, the new generation 'omics' (metagenomics, transcriptomics, proteomics, and metabolomics) technologies made it possible to precisely identify microbiota and metabolites and describe their variability between individuals, populations and even different time points within the same subjects. With massive efforts made, it is now generally accepted that the gut microbiota is a dynamically changing population, whose composition is influenced by the hosts' health conditions and lifestyles. Diet is one of the major contributors to shaping the gut microbiota. The components in the diets vary in different countries, religions, and populations. Some special diets have been adopted by people for hundreds of years aiming for better health, while the underlying mechanisms remain largely unknown. Recent studies based on volunteers or diet-treated animals demonstrated that diets can greatly and rapidly change the gut microbiota. The unique pattern of the nutrients from the diets and their metabolites produced by the gut microbiota has been linked with the occurrence of diseases, including obesity, diabetes, nonalcoholic fatty liver disease, cardiovascular disease, neural diseases, and more. This review will summarize the recent progress and current understanding of the effects of different dietary patterns on the composition of gut microbiota, bacterial metabolites, and their effects on the host's metabolism.

The gut microbiota-astrocyte axis: Implications for type 2 diabetic cognitive dysfunction

BACKGROUND

Diabetic cognitive dysfunction (DCD) is one of the most insidious complications of type 2 diabetes mellitus, which can seriously affect the ability to self-monitoring of blood glucose and the quality of life in the elderly. Previous pathological studies of cognitive dysfunction have focused on neuronal dysfunction, characterized by extracellular beta-amyloid deposition and intracellular tau hyperphosphorylation. In recent years, astrocytes have been recognized as a potential therapeutic target for cognitive dysfunction and important participants in the central control of metabolism. The disorder of gut microbiota and their metabolites have been linked to a series of metabolic diseases such as diabetes mellitus. The imbalance of intestinal flora has the effect of promoting the occurrence and deterioration of several diabetes-related complications. Gut microbes and their metabolites can drive astrocyte activation.

AIMS

We reviewed the pathological progress of DCD related to the "gut microbiota-astrocyte" axis in terms of peripheral and central inflammation, intestinal and blood-brain barrier (BBB) dysfunction, systemic and brain energy metabolism disorders to deepen the pathological research progress of DCD and explore the potential therapeutic targets.

CONCLUSION

"Gut microbiota-astrocyte" axis, unique bidirectional crosstalk in the brain-gut axis, mediates the intermediate pathological process of neurocognitive dysfunction secondary to metabolic disorders in diabetes mellitus.

Dietary Supplementation with Milk Lipids Leads to Suppression of Developmental and Behavioral Phenotypes of Hyperexcitable Drosophila Mutants

Dietary modifications often have a profound impact on the penetrance and expressivity of neurological phenotypes that are caused by genetic defects. Our previous studies in Drosophila melanogaster revealed that seizure-like phenotypes of gain-of-function voltage-gated sodium (Nav) channel mutants (paraShu, parabss1, and paraGEFS+), as well as other seizure-prone "bang-sensitive" mutants (eas and sda), were drastically suppressed by supplementation of a standard diet with milk whey. In the current study we sought to determine which components of milk whey are responsible for the diet-dependent suppression of their hyperexcitable phenotypes. Our systematic analysis reveals that supplementing the diet with a modest amount of milk lipids (0.26% w/v) mimics the effects of milk whey. We further found that a minor milk lipid component, α-linolenic acid, contributed to the diet-dependent suppression of adult paraShu phenotypes. Given that lipid supplementation during the larval stages effectively suppressed adult paraShu phenotypes, dietary lipids likely modify neural development to compensate for the defects caused by the mutations. Consistent with this notion, lipid feeding fully rescued abnormal dendrite development of class IV sensory neurons in paraShu larvae. Overall, our findings demonstrate that milk lipids are sufficient to ameliorate hyperexcitable phenotypes in Drosophila mutants, providing a foundation for future investigation of the molecular and cellular mechanisms by which dietary lipids modify genetically induced abnormalities in neural development, physiology, and behavior.

Neurodegenerative and Neurodevelopmental Diseases and the Gut-Brain Axis: The Potential of Therapeutic Targeting of the Microbiome

The human gut microbiome contains the largest number of bacteria in the body and has the potential to greatly influence metabolism, not only locally but also systemically. There is an established link between a healthy, balanced, and diverse microbiome and overall health. When the gut microbiome becomes unbalanced (dysbiosis) through dietary changes, medication use, lifestyle choices, environmental factors, and ageing, this has a profound effect on our health and is linked to many diseases, including lifestyle diseases, metabolic diseases, inflammatory diseases, and neurological diseases. While this link in humans is largely an association of dysbiosis with disease, in animal models, a causative link can be demonstrated. The link between the gut and the brain is particularly important in maintaining brain health, with a strong association between dysbiosis in the gut and neurodegenerative and neurodevelopmental diseases. This link suggests not only that the gut microbiota composition can be used to make an early diagnosis of neurodegenerative and neurodevelopmental diseases but also that modifying the gut microbiome to influence the microbiome-gut-brain axis might present a therapeutic target for diseases that have proved intractable, with the aim of altering the trajectory of neurodegenerative and neurodevelopmental diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, autism spectrum disorder, and attention-deficit hyperactivity disorder, among others. There is also a microbiome-gut-brain link to other potentially reversible neurological diseases, such as migraine, post-operative cognitive dysfunction, and long COVID, which might be considered models of therapy for neurodegenerative disease. The role of traditional methods in altering the microbiome, as well as newer, more novel treatments such as faecal microbiome transplants and photobiomodulation, are discussed.

Effects of ketogenic diet on health outcomes: an umbrella review of meta-analyses of randomized clinical trials

BACKGROUND

Systematic reviews and meta-analyses of randomized clinical trials (RCTs) have reported the benefits of ketogenic diets (KD) in various participants such as patients with epilepsy and adults with overweight or obesity. Nevertheless, there has been little synthesis of the strength and quality of this evidence in aggregate.

METHODS

To grade the evidence from published meta-analyses of RCTs that assessed the association of KD, ketogenic low-carbohydrate high-fat diet (K-LCHF), and very low-calorie KD (VLCKD) with health outcomes, PubMed, EMBASE, Epistemonikos, and Cochrane database of systematic reviews were searched up to February 15, 2023. Meta-analyses of RCTs of KD were included. Meta-analyses were re-performed using a random-effects model. The quality of evidence per association provided in meta-analyses was rated by the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) criteria as high, moderate, low, and very low.

RESULTS

We included 17 meta-analyses comprising 68 RCTs (median [interquartile range, IQR] sample size of 42 [20-104] participants and follow-up period of 13 [8-36] weeks) and 115 unique associations. There were 51 statistically significant associations (44%) of which four associations were supported by high-quality evidence (reduced triglyceride (n = 2), seizure frequency (n = 1) and increased low-density lipoprotein cholesterol (LDL-C) (n = 1)) and four associations supported by moderate-quality evidence (decrease in body weight, respiratory exchange ratio (RER), hemoglobin A_1c, and increased total cholesterol). The remaining associations were supported by very low (26 associations) to low (17 associations) quality evidence. In overweight or obese adults, VLCKD was significantly associated with improvement in anthropometric and cardiometabolic outcomes without worsening muscle mass, LDL-C, and total cholesterol. K-LCHF was associated with reduced body weight and body fat percentage, but also reduced muscle mass in healthy participants.

CONCLUSIONS

This umbrella review found beneficial associations of KD supported by moderate to high-quality evidence on seizure and several cardiometabolic parameters. However, KD was associated with a clinically meaningful increase in LDL-C. Clinical trials with long-term follow-up are warranted to investigate whether the short-term effects of KD will translate to beneficial effects on clinical outcomes such as cardiovascular events and mortality.

Akkermansia muciniphila-Nlrp3 is involved in the neuroprotection of phosphoglycerate mutase 5 deficiency in traumatic brain injury mice

Introduction

Gut-microbiota-brain axis is a potential treatment to decrease the risk of chronic traumatic encephalopathy following traumatic brain injury (TBI). Phosphoglycerate mutase 5 (PGAM5), a mitochondrial serine/threonine protein phosphatase, resides in mitochondrial membrane and regulates mitochondrial homeostasis and metabolism. Mitochondria mediates intestinal barrier and gut microbiome.

Objectives

This study investigated the association between PGAM5 and gut microbiota in mice with TBI.

Methods

The controlled cortical impact injury was established in mice with genetically-ablated Pgam5 (Pgam5^-/-) or wild type, and WT male mice were treated with fecal microbiota transplantation (FMT) from male Pgam5^-/- mice or Akkermansia muciniphila (A. muciniphila). Then the gut microbiota abundance, blood metabolites, neurological function, and nerve injury were detected.

Results

Treated with antibiotics for suppressing gut microbiota in Pgam5^-/- mice partially relieved the role of Pgam5 deficiency in the improvement of initial inflammatory factors and motor dysfunction post-TBI. Pgam5 knockout exhibited an increased abundance of A. muciniphila in mice. FMT from male Pgam5^-/- mice enabled better maintenance of amino acid metabolism and peripherial environment than that in TBI-vehicle mice, which suppressed neuroinflammation and improved neurological deficits, and A. muciniphila was negatively associated with intestinal mucosal injury and neuroinflammation post-TBI. Moreover, A. muciniphila treatment ameliorated neuroinflammation and nerve injury by regulating Nlrp3 inflammasome activation in cerebral cortex with TBI.

Conclusion

Thus, the present study provides evidence that Pgam5 is involved in gut microbiota-mediated neuroinflammation and nerve injury, with A. muciniphila-Nlrp3 contributing to peripheral effects.