Selective modulator of peroxisome proliferator-activated receptor-α protects propionic acid induced autism-like phenotypes in rats

ML218 modulates calcium binding protein, oxidative stress, and inflammation during ischemia-reperfusion brain injury in mice

Cerebral ischemia disrupts calcium homeostasis in the brain causing excitotoxicity, oxidative stress, inflammation, and neuronal cell apoptosis. During ischemic conditions, T-type calcium channel channels contribute to increase in intracellular calcium ions in both neurons and glial cells therefore, the current study hypothesizes the antagonism of these channels using ML218, a novel specific T-Type inhibitor in experimental model of cerebral ischemia-reperfusion (CI/R) brain injury. CI/R injury was induced in Swiss Albino mice by occlusion of common carotid arteries followed by reperfusion. Animals were assessed for learning and memory (MWM), motor coordination (Rota rod), neurological function (neurological deficit score), cerebral infarction, edema, and histopathological alterations. Biochemical assessments were made for calcium binding proteins (Calmodulin- CaM, calcium/calmodulin-dependent protein kinase II-CaMKII, S100B), oxidative stress (4-hydroxy 2-nonenal-4-HNE, glutathione-GSH, inflammation (nuclear factor kappa-light-chain-enhancer of activated B-p65-NF-kB, tumor necrosis factor-TNF-α, interleukin-IL-10) inducible nitric oxide synthase (iNOS) levels, and acetylcholinesterase activity (AChE) in brain supernatants. Furthermore, serum levels of NF-kB, iNOS, and S100B were also assessed. CI/R animals showed impairment in learning, memory, motor coordination, and neurological function along with increase in cerebral infarction, edema, and histopathological alterations. Furthermore, increase in brain calcium binding proteins, oxidative stress, inflammation, and AChE activity along with serum NF-kB, iNOS, and S100B levels were recorded in CI/R animals. Administration of ML218 (5 mg/kg and 10 mg/kg; i.p.) was observed to recuperate CI/R induced impairments in behavioral, biochemical, and histopathological analysis. Hence, it may be concluded that ML218 mediates neuroprotection during CI/R via decreasing brain and serum calcium binding proteins, inflammation, iNOS, and oxidative stress markers.

A snapshot on introspection of autism spectrum disorder

Autism spectrum disorder is a neurodevelopmental condition marked by restricted interests and difficulty with social communication. ASD is characterized by heightened neuroinflammation and irregular neuronal connections. ASD is more frequent in male than female with male-female ratio of around 4:1. ASD affects 2.8% or 1 in 36 8-year-olds, based on the CDC's Morbidity and Mortality Weekly Report. Various factors like Environmental, Genetic, Epigenetic and Developmental factors are linked with genesis of ASD. Repetitive behaviors, Impaired communication skills, difficulty with social interaction are some of the clinical features of ASD. Current Pharmacotherapy of ASD limits to management of symptoms only, not cure. The stem cell therapy has a promising potential to be a breakthrough in treating ASD. Various types of stem cells have been successfully tested in children with ASD. AI has a potential to emerge as a tool for early detection of ASD. Robotics can assist the children with ASD to overcome the challenges associated with ASD.

Ameliorating effect of pioglitazone on prenatal valproic acid-induced behavioral and neurobiological abnormalities in autism spectrum disorder in rats

Autism spectrum disorder (ASD) is a neurodevelopment disorder that mainly arises due to abnormalities in different brain regions, resulting in behavioral deficits. Besides its diverse phenotypical features, ASD is associated with complex and varied etiology, presenting challenges in understanding its precise neuro-pathophysiology. Pioglitazone was reported to have a fundamental role in neuroprotection in various other neurological disorders. The present study aimed to investigate the therapeutic potential of pioglitazone in the prenatal valproic acid (VPA)-model of ASD in Wistar rats. Pregnant female Wistar rats received VPA on Embryonic day (E.D12.5) to induce autistic-like-behavioral and neurobiological alterations in their offspring. VPA-exposed rats presented core behavioral symptoms of ASD such as deficits in social interaction, poor spatial and learning behavior, increased anxiety, locomotory and repetitive activity, and decreased exploratory activity. Apart from these, VPA exposure also stimulated neurochemical and histopathological neurodegeneration in various brain regions. We administered three different doses of pioglitazone i.e., 2.5, 5, and 10 mg/kg in rats to assess various parameters. Of all the doses, our study highlighted that 10 mg/kg pioglitazone efficiently attenuated the autistic symptoms along with other neurochemical alterations such as oxidative stress, neuroinflammation, and apoptosis. Moreover, pioglitazone significantly attenuated the neurodegeneration by restoring the neuronal loss in the hippocampus and cerebellum. Taken together, our study suggests that pioglitazone exhibits therapeutic potential in alleviating behavioral abnormalities induced by prenatal VPA exposure in rats. However, further research is needed to fully understand and establish pioglitazone's effectiveness in treating ASD.

Evaluation of Wnt/β-catenin signaling and its modulators in repeated dose lithium-pilocarpine rat model of status epilepticus: An acute phase study

The role of the Wnt/β-catenin signaling pathway in epilepsy and the effects of its modulators as efficacious treatment options, though postulated, has not been sufficiently investigated. We evaluated the involvement of β-catenin and GSK-3β, the significant proteins in this pathway, in the lithium chloride-pilocarpine-induced status epilepticus model in rodents to study acute phase of temporal lobe epilepsy (TLE). The modulators studied were 6-BIO, a GSK-3β inhibitor and Sulindac, a Dvl protein inhibitor. The disease group exhibited increased seizure score and seizure frequency, and the assessment of neurobehavioral parameters indicated notable alterations. Furthermore, histopathological examination of hippocampal brain tissues revealed significant neurodegeneration. Immunohistochemical study of hippocampus revealed neurogenesis in 6-BIO and sulindac groups. The gene and protein expression by RT-qPCR and western blotting studies indicated Wnt/β-catenin pathway downregulation and increased apoptosis in the acute phase of TLE. 6-BIO was very efficient in upregulating the Wnt pathway, decreasing neuronal damage, increasing neurogenesis in hippocampus and decreasing seizure score and frequency in comparison to sulindac. This suggests that both GSK-3β and β-catenin are potential and novel drug targets for acute phase of TLE, and treatment options targeting these proteins could be beneficial in successfully managing acute epilepsy. Further evaluation of 6-BIO to explore its therapeutic potential in other models of epilepsy should be conducted.

Phosphodiesterase inhibitor, ibudilast alleviates core behavioral and biochemical deficits in the prenatal valproic acid exposure model of autism spectrum disorder

BACKGROUND

Autism spectrum disorder (ASD) is categorized as a neurodevelopmental disorder, presenting with a variety of aetiological and phenotypical features. Ibudilast is known to produce beneficial effects in several neurological disorders including neuropathic pain, multiple sclerosis, etc. by displaying its neuroprotective and anti-inflammatory properties. Here, in our study, the pharmacological outcome of ibudilast administration was investigated in the prenatal valproic acid (VPA)-model of ASD in Wistar rats.

METHODS

Autistic-like symptoms were induced in Wistar male pups of dams administered with Valproic acid (VPA) on embryonic day 12.5. VPA-exposed male pups were administered with two doses of ibudilast (5 and10 mg/kg) and all the groups were evaluated for behavioral parameters like social interaction, spatial memory/learning, anxiety, locomotor activity, and nociceptive threshold. Further, the possible neuroprotective effect of ibudilast was evaluated by assessing oxidative stress, neuroinflammation (IL-1β, TNF-α, IL-6, IL-10) in the hippocampus, % area of Glial fibrillary acidic protein (GFAP)-positive cells and neuronal damage in the cerebellum.

KEY FINDINGS

Treatment with ibudilast significantly attenuated prenatal VPA exposure associated social interaction and spatial learning/memory deficits, anxiety, hyperactivity, and increased nociceptive threshold, and it decreased oxidative stress markers, pro-inflammatory markers (IL-1β, TNF-α, IL-6), and % area of GFAP-positive cells and restored neuronal damage.

CONCLUSIONS

Ibudilast treatment has restored crucial ASD-related behavioural abnormalities, potentially through neuroprotection. Therefore, benefits of ibudilast administration in animal models of ASD suggest that ibudilast may have therapeutic potential in the treatment of ASD.

Calcium voltage-gated channel subunit alpha 1 C and glial fibrillary acidic protein signaling pathways as a selective biomarker in predicting the efficacy of liposomal loaded co-enzyme Q in the autistic rat model

Autism spectrum disorder (ASD) is an extreme neuropsychotic disturbance with both environmental and genetic origins. Sodium propionate (PPA) a metabolic bioproduct of gut microbiota is well-thought-out as a successful autism animal model. Nevertheless, Liposomal drug delivery system possess the advantagous of biocompatibility, targeting organs, ability to carry large drug payloads and skipping macrophages for this purpose the current study was carried out to investigate the hypothesis that Calcium Voltage-Gated channel subunit alpha 1 C (CACNA1C) and glial fibrillary acidic protein (GFAP) signaling pathways crosstalk with the efficacy of Co-enzyme Q10 (Co-Q10) and liposomal loaded Co-enzyme Q10 (L Co-Q10) in PPA mediated autistic rat model. Autism was conducted by buffered PPA (500 mg/Kg b.wt) daily for 5 consecutive days subsequently treatment via Co-Q10 in a dose of (10 mg/kg b.wt) and L Co-Q10 (2 mg/kg b.wt) for four weeks then the autistic model was followed for signs of autism at different time intervals of (one, two and four weeks). The control, PPA intoxicated, and treated groups were subjected to behavioral tests (Y-Maze and open field), antioxidant analysis, gene expression analysis, and histological examination at different time intervals of the study. The results revealed that Co-Q10 and L Co-Q10 significantly elevated antioxidative stress biomarkers, comprising superoxide dismutase (SOD), glutathione (GSH), and total antioxidant capacity (TAC). In addition, they significantly ameliorated the oxidative stress biomarker malondialdehyde (MDA). Meanwhile, they significantly downregulated GFAP and CACNA1C mRNA gene expressions, Co-Q10 and LCo-Q10 showed improvement in almost brain regions post PPA histopathological alterations, even better results were manifested via LCo-Q10 groups. These results showed the superiority of LCo-Q10 over Co-Q10 in competing autism. In conclusion: The administration of anti-inflammatory and antioxidant agents such as Co-Q10 and L Co-Q10 may represent a promising strategy to counteract pathological behaviors in ASD model via targeting organs, increasing retention time, and reducing side effects.

Vinpocetine, a PDE1 modulator, regulates markers of cerebral health, inflammation, and oxidative stress in a rat model of prenatal alcohol-induced experimental attention deficit hyperactivity disorder

Prenatal alcohol exposure (PAE) has been shown to induce symptomatology associated with attention deficit hyperactivity disorder (ADHD) by altering neurodevelopmental trajectories. Phosphodiesterase-1 (PDE1) is expressed centrally and has been used in various experimental brain conditions. We investigated the role of vinpocetine, a PDE1 inhibitor, on behavioral phenotypes and important biochemical deficits associated with a PAE rat model of ADHD. Protein markers of cerebral health (synapsin-IIa, BDNF, and pCREB), inflammation (IL-6, IL-10, and TNF-α), and oxidative stress (TBARS, GSH, and SOD) were analyzed in three brain regions (frontal cortex, striatum, and cerebellum). Hyperactivity, inattention, and anxiety introduced in the offspring due to PAE were assayed using open-field, Y-maze, and elevated plus maze, respectively. Administration of vinpocetine (10 & 20 mg/kg, p.o. [by mouth]) to PAE rat offspring for 4 weeks resulted in improvement of the behavioral profile of the animals. Additionally, levels of protein markers such as synapsin-IIa, BDNF, pCREB, IL-10, SOD, and GSH were found to be significantly increased, with a significant reduction in markers such as TNF-α, IL-6, and TBARS in selected brain regions of vinpocetine-treated animals. Vinpocetine, a selective PDE1 inhibitor, rectified behavioral phenotypes associated with ADHD, possibly by improving cerebral function, reducing brain inflammation, and reducing brain oxidative stress. This study provides preliminary analysis and suggests that the PDE1 enzyme may be an important pharmacological tool to study ADHD as a result of PAE.

Protective Effect of Nimodipine Against Valproic-acid Induced Biochemical and Behavioral Phenotypes of Autism

Objective

Present study was designed to investigate behavioral and biochemical role of nimodipine in prenatal valproic acid (Pre-VPA) induced autism in rats.

Methods

Valproic acid was utilized to induce autistic phenotypes in Wistar rats. The rats were assessed for social behavior. Hippocampus and prefrontal cortex (PFC) were utilized for various biochemical assessments, whereas cerebellum was used to assess blood brain barrier (BBB) permeability.

Results

Pre-VPA rats showed reduction social interaction. Pre-VPA administration were decreased PFC levels of interleukin- 10 (IL-10), and glutathione along with hippocampus cAMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF). Also, the animals have shown increase in PFC levels of IL-6, tumor necrosis factor-α, thiobarbituric acid reactive substance, Evans blue leakage and water content. Nimodipine countered Pre-VPA administered reduction in social interaction, CREB, BDNF, inflammation, oxidative stress, BBB permeability.

Conclusion

Pre-VPA has induced autistic phenotype, which were attenuated by nimodipine in rats. Nimodipine and other calcium channel blockers should further investigate to check the management of autism.

Novel role of peroxisome proliferator activated receptor-α in valproic acid rat model of autism: Mechanistic study of risperidone and metformin monotherapy versus combination

Autism spectrum disorder (ASD) is a neurodevelopmental disorder of heterogenous etiology exhibiting a challenge in understanding its exact neuro-pathophysiology. Recently, peroxisome proliferator activated receptor (PPAR)-α activation was found to play a fundamental role in neuroprotection and improving autistic-like-behaviors in experimental animal models of ASD through alleviating neuroinflammation, oxidative-stress, astrocyte reactivity, tauopathy in addition to its favorable role in metabolic regulation, thus attracting attention as a possible target in treatment of ASD. This study aimed to investigate the role of PPAR-α, astrocytic dysfunction and tauopathy in ASD and detect the possible neuroprotective effects of metformin (MET), through PPAR-α activation, and risperidone (RIS) either monotherapy or in combination in alleviating autistic-like-changes at behavioral and neurobiological levels in male Wistar rats. Pregnant female Wistar rats received valproic-acid (VPA) to induce autistic-like-behavioral and neurobiological alterations in their offspring. Chronic intra-peritoneal MET (100 mg/kg/day) and RIS (1 mg/kg/day) either monotherapy or in combination started from postnatal day (PND) 24 till PND61 (38 days). Prenatal VPA exposure simulated the autistic core behaviors associated with neurochemical and histopathological neurodevelopmental degenerative changes. Both MET and RIS either monotherapy or in combination were able to reverse these changes. The effect of MET was comparable to RIS. Moreover, MET was able to alleviate the RIS induced weight gain and improve cognitive functions highlighting its promising adjunctive role in alleviating ASD pathophysiology. Our study highlighted the favorable effects of MET and RIS both in monotherapy and in combination in alleviating the autistic-like-changes and proposed PPAR-α activation along with restoring astrocytes homeostasis as promising targets in novel therapeutic strategies in ASD.

PPARα Signaling: A Candidate Target in Psychiatric Disorder Management

Peroxisome proliferator-activator receptors (PPARs) regulate lipid and glucose metabolism, control inflammatory processes, and modulate several brain functions. Three PPAR isoforms have been identified, PPARα, PPARβ/δ, and PPARγ, which are expressed in different tissues and cell types. Hereinafter, we focus on PPARα involvement in the pathophysiology of neuropsychiatric and neurodegenerative disorders, which is underscored by PPARα localization in neuronal circuits involved in emotion modulation and stress response, and its role in neurodevelopment and neuroinflammation. A multiplicity of downstream pathways modulated by PPARα activation, including glutamatergic neurotransmission, upregulation of brain-derived neurotrophic factor, and neurosteroidogenic effects, encompass mechanisms underlying behavioral regulation. Modulation of dopamine neuronal firing in the ventral tegmental area likely contributes to PPARα effects in depression, anhedonia, and autism spectrum disorder (ASD). Based on robust preclinical evidence and the initial results of clinical studies, future clinical trials should assess the efficacy of PPARα agonists in the treatment of mood and neurodevelopmental disorders, such as depression, schizophrenia, and ASD.

Guggulsterone Mediated JAK/STAT and PPAR-Gamma Modulation Prevents Neurobehavioral and Neurochemical Abnormalities in Propionic Acid-Induced Experimental Model of Autism

Autism spectrum disorder is a neurodevelopmental disorder marked by repetitive behaviour, challenges in verbal and non-verbal communication, poor socio-emotional health, and cognitive impairment. An increased level of signal transducer and activator of transcription 3 (STAT3) and a decreased level of peroxisome proliferator-activated receptor (PPAR) gamma have been linked to autism pathogenesis. Guggulsterone (GST) has a neuroprotective effect on autistic conditions by modulating these signalling pathways. Consequently, the primary objective of this study was to examine potential neuroprotective properties of GST by modulating JAK/STAT and PPAR-gamma levels in intracerebroventricular propionic acid (ICV PPA) induced experimental model of autism in adult rats. In this study, the first 11 days of ICV-PPA injections in rats resulted in autism-like behavioural, neurochemical, morphological, and histopathological changes. The above modifications were also observed in various biological samples, including brain homogenate, CSF, and blood plasma. GST was also observed to improve autism-like behavioural impairments in autistic rats treated with PPA, including locomotion, neuromuscular coordination, depression-like behaviour, spatial memory, cognition, and body weight. Prolonged GST treatment also restored neurochemical deficits in a dose-dependent manner. Chronic PPA administration increased STAT3 and decreased PPAR gamma in autistic rat brain, CSF, and blood plasma samples, which were reversed by GST. GST also restored the gross and histopathological alterations in PPA-treated rat brains. Our results indicate the neuroprotective effects of GST in preventing autism-related behavioural and neurochemical alterations.

Cardiovascular therapeutics: A new potential for anxiety treatment?

Besides the well‐recognized risk factors, novel conditions increasing cardiovascular morbidity and mortality are emerging. Undesirable emotions and behavior such as anxiety and depression, appear to participate in worsening cardiovascular pathologies. On the other hand, deteriorating conditions of the heart and vasculature result in disturbed mental and emotional health. The pathophysiological background of this bidirectional interplay could reside in an inappropriate activation of vegetative neurohormonal and other humoral systems in both cardiovascular and psychological disturbances. This results in circulus vitiosus potentiating mental and circulatory disorders. Thus, it appears to be of utmost importance to examine the alteration of emotions, cognition, and behavior in cardiovascular patients. In terms of this consideration, recognizing the potential of principal cardiovascular drugs to interact with the mental state in patients with heart or vasculature disturbances is unavoidable, to optimize their therapeutic benefit. In general, beta‐blockers, central sympatholytics, ACE inhibitors, ARBs, aldosterone receptor blockers, sacubitril/valsartan, and fibrates are considered to exert anxiolytic effect in animal experiments and clinical settings. Statins and some beta‐blockers appear to have an equivocal impact on mood and anxiety and ivabradine expressed neutral psychological impact. It seems reasonable to suppose that the knowledge of a patient's mood, cognition, and behavior, along with applying careful consideration of the choice of the particular cardiovascular drug and respecting its potential psychological benefit or harm might improve the individualized approach to the treatment of cardiovascular disorders.

Lactobacillus plantarum PS128 prevents cognitive dysfunction in Alzheimer's disease mice by modulating propionic acid levels, glycogen synthase kinase 3 beta activity, and gliosis

Background

According to recent evidence, psychobiotics exert beneficial effects on central nervous system-related diseases, such as mental disorders. Lactobacillus plantarum PS128 (PS128), a novel psychobiotic strain, improves motor function, depression, and anxiety behaviors. However, the psychobiotic effects and mechanisms of PS128 in Alzheimer’s disease (AD) remain to be explored.

Objectives

The goal of the current study was to evaluate the beneficial effects of PS128 and to further elucidate its mechanism in AD mice.

Methods

PS128 (10¹⁰ colony-forming unit (CFU)/ml) was administered via oral gavage (o.g.) to 6-month-old male wild-type B6 and 3 × Tg-AD mice (harboring the PS1M146V, APPswe and TauP30IL transgenes) that received an intracerebroventricular injection of streptozotocin (icv-STZ, 3 mg/kg) or vehicle (saline) for 33 days. After serial behavioral tests, fecal short-chain fatty acid levels and AD-related pathology were assessed in these mice.

Results

Our findings show that intracerebroventricular injection of streptozotocin accelerated cognitive dysfunction associated with increasing levels of glycogen synthase kinase 3 beta (GSK3β) activity, tau protein phosphorylation at the T231 site (pT231), amyloid-β (Aβ) deposition, amyloid-β protein precursor (AβPP), β-site AβPP-cleaving enzyme (BACE1), gliosis, fecal propionic acid (PPA) levels and cognition-related neuronal loss and decreasing postsynaptic density protein 95 (PSD95) levels in 3 × Tg-AD mice. PS128 supplementation effectively prevented the damage induced by intracerebroventricular injection of streptozotocin in 3 × Tg-AD mice.

Conclusions

Based on the experimental results, intracerebroventricular injection of streptozotocin accelerates the progression of AD in the 3 × Tg-AD mice, primarily by increasing the levels of gliosis, which were mediated by the propionic acid and glycogen synthase kinase 3 beta pathways. PS128 supplementation prevents damage induced by intracerebroventricular injection of streptozotocin by regulating the propionic acid levels, glycogen synthase kinase 3 beta activity, and gliosis in 3 × Tg-AD mice. Therefore, we suggest that PS128 supplementation is a potential strategy to prevent and/or delay the progression of AD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03426-8.

Cilostazol attenuated prenatal valproic acid-induced behavioural and biochemical deficits in a rat model of autism spectrum disorder

OBJECTIVES

Autism spectrum disorder (ASD) is categorized as a neurodevelopmental disorder, presenting with a variety of aetiological and phenotypical features. Inhibiting the enzyme phosphodiesterase-3 (PDE3) with cilostazol is known to produce beneficial effects in several brain disorders. The pharmacological outcome of cilostazol administration was investigated in prenatal valproic acid (VPA)-induced ASD deficits in albino Wistar rats.

METHODS

Cilostazol was administered in two doses (30/60 mg/kg) to male rats born of females administered with VPA on gestational day 12. Behavioural assays on locomotion (open field), social interaction, repetitive behaviour (y-maze) and anxiety (elevated plus maze) were performed in all groups. Further, biochemical assessments of markers associated with neuronal function (BDNF, pCREB), inflammation (TNF-α, IL-6, IL-10) and oxidative stress were carried out in frontal cortex, hippocampus, striatum and cerebellum.

KEY FINDINGS

The cilostazol regimen, attenuated prenatal VPA exposure associated hyperlocomotion, social interaction deficits, repetitive behavior, and anxiety. Further, biochemical markers such as BDNF, pCREB, IL-10 and GSH were found to be significantly increased contrary to markers such as TNF-α, IL-6 and TBARS in the assessed brain regions.

CONCLUSIONS

Cilostazol rectified core behavioural traits while producing significant changes to biochemistry in the brain, suggesting benefits of cilostazol administration in experimental models of ASD.

Vinpocetine amended prenatal valproic acid induced features of ASD possibly by altering markers of neuronal function, inflammation, and oxidative stress

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with complex etiology and phenotypes. Phosphodiesterase-1 (PDE1) inhibitors are known to provide benefits in various brain conditions manifesting similar behavioral phenotypes. The pharmacological consequences of vinpocetine administration a PDE1 inhibitor in prenatal-valproic acid (pre-VPA) induced ASD related behavioral phenotypes (social behavior deficits, repetitive behavior, anxiety, hyperlocomotion, and nociception) was assessed. Also, effects on important biochemical markers of neuronal function (DCX-neurogenesis, BDNF-neuronal survival, synapsin-IIa-synaptic transmission, pCREB-neuronal transcription factor), inflammation (interleukin [IL]-6, IL-10, and TNF-α) and oxidative stress (thiobarbituric acid reactive substance [TBARS] and glutathione (GSH) were studied in important brain areas (frontal cortex, cerebral cortex, hippocampus, and striatum). Further, neuronal cell viability was determined in dentate gyrus using Nissl staining. Pre-VPA administration resulted into impaired behavior, brain biochemistry, and neuronal cell viability. Administration of vinpocetine resulted in improvements of pre-VPA impaired social behavior, repetitive behavior, anxiety, locomotion, and nociception. Also, vinpocetine resulted in a significant increase in the levels of BDNF, synapsin-IIa, DCX, pCREB/CREB, IL-10, and GSH along with significant decrease in TNF-α, IL-6, TBARS, number of pyknotic and chromatolytic cells in different brain areas of pre-VPA group. Finally, high association between behavioral parameters and biochemical parameters was observed upon Pearson's correlation analysis. Vinpocetine, a PDE1 inhibitor rectified important behavioral phenotypes related with ASD, possibly by improving neuronal function, brain inflammation and brain oxidative stress. Thus, PDE1 may be a possible target for further understanding ASD. LAY SUMMARY: ASD is a brain developmental disorder with a wide array of genetic and environmental factors. Many targets have been identified till date, but a clinical treatment is still afar. The results of this study indicate that vinpocetine administration resulted in amelioration of ASD associated symptomatology in rats, prenatally exposed to VPA. Our research adds a widely expressed brain enzyme PDE1, as a possible novel pharmacological target and opens-up a new line of enquiry for ASD treatment.

Fecal Transplant and Bifidobacterium Treatments Modulate Gut Clostridium Bacteria and Rescue Social Impairment and Hippocampal BDNF Expression in a Rodent Model of Autism

Autism is associated with gastrointestinal dysfunction and gut microbiota dysbiosis, including an overall increase in Clostridium. Modulation of the gut microbiota is suggested to improve autistic symptoms. In this study, we explored the implementation of two different interventions that target the microbiota in a rodent model of autism and their effects on social behavior: the levels of different fecal Clostridium spp., and hippocampal transcript levels. Autism was induced in young Sprague Dawley male rats using oral gavage of propionic acid (PPA) for three days, while controls received saline. PPA-treated animals were divided to receive either saline, fecal transplant from healthy donor rats, or Bifidobacterium for 22 days, while controls continued to receive saline. We found that PPA attenuated social interaction in animals, which was rescued by the two interventions. PPA-treated animals had a significantly increased abundance of fecal C. perfringens with a concomitant decrease in Clostridium cluster IV, and exhibited high hippocampal Bdnf expression compared to controls. Fecal microbiota transplantation or Bifidobacterium treatment restored the balance of fecal Clostridium spp. and normalized the level of Bdnf expression. These findings highlight the involvement of the gut-brain axis in the etiology of autism and propose possible interventions in a preclinical model of autism.

Oleoylethanolamide Delays the Dysfunction and Death of Purkinje Cells and Ameliorates Behavioral Defects in a Mouse Model of Cerebellar Neurodegeneration

Oleoylethanolamide (OEA) is an endocannabinoid that has been proposed to prevent neuronal damage and neuroinflammation. In this study, we evaluated the effects of OEA on the disruption of both cerebellar structure and physiology and on the behavior of Purkinje cell degeneration (PCD) mutant mice. These mice exhibit cerebellar degeneration, displaying microtubule alterations that trigger the selective loss of Purkinje cells and consequent behavioral impairments. The effects of different doses (1, 5, and 10 mg/kg, i.p.) and administration schedules (chronic and acute) of OEA were assessed at the behavioral, histological, cellular, and molecular levels to determine the most effective OEA treatment regimen. Our in vivo results demonstrated that OEA treatment prior to the onset of the preneurodegenerative phase prevented morphological alterations in Purkinje neurons (the somata and dendritic arbors) and decreased Purkinje cell death. This effect followed an inverted U-shaped time-response curve, with acute administration on postnatal day 12 (10 mg/kg, i.p.) being the most effective treatment regimen tested. Indeed, PCD mice that received this specific OEA treatment regimen showed improvements in motor, cognitive and social functions, which were impaired in these mice. Moreover, these in vivo neuroprotective effects of OEA were mediated by the PPARα receptor, as pretreatment with the PPARα antagonist GW6471 (2.5 mg/kg, i.p.) abolished them. Finally, our in vitro results suggested that the molecular effect of OEA was related to microtubule stability and structure since OEA administration normalized some alterations in microtubule features in PCD-like cells. These findings provide strong evidence supporting the use of OEA as a pharmacological agent to limit severe cerebellar neurodegenerative processes.

Effect of papaverine on developmental hyperserotonemia induced autism spectrum disorder related behavioural phenotypes by altering markers of neuronal function, inflammation, and oxidative stress in rats

Hyperserotonemia, in the early developmental phase, generates a variety of behavioural and biochemical phenotypes associated with autism spectrum disorder (ASD) in rats. Papaverine is known to provide benefits in various brain conditions. We investigated the role of a selective phosphodiesterase-10A (PDE10A) inhibitor, papaverine on ASD related behavioural phenotypes (social behaviour deficits, repetitive behaviour, anxiety and hyperlocomotion) in developmental hyperserotonemia (DHS) rat model. Also, effects on important biochemical markers related with neuronal function (brain-derived neurotrophic factor (BDNF)-neuronal survival and phosphorylated-cAMP response element binding protein (pCREB)-neuronal transcription factor), brain inflammation (interleukin (IL)-6, IL-10 and tumour necrosis factor (TNF)-α) and brain oxidative stress (TBARS and GSH) were studied in important brain areas (frontal cortex, cerebellum, hippocampus and striatum). Administration of a non-selective serotonin receptor agonist, such as 5-methoxytryptamine (5-MT) to rats prenatally (gestational day 12 - day of parturition) and during early stages (postnatal day (PND) 0 -PND20) of development, resulted in impaired behaviour and brain biochemistry. Administration of papaverine (15/30 mg/kg ip) to 5-MT administered rats from PND21 to PND48, resulted in improvement of behavioural deficits. Also, papaverine administration significantly increased the levels of BDNF, pCREB/CREB, IL-10, GSH and significantly decreased TNF-α, IL-6 and TBARS levels in different brain areas. Papaverine, in both doses rectified important behavioural phenotypes related with ASD, the higher dose (30 mg/kg ip) showed significantly greater improvement than 15 mg/kg ip, possibly by improving neuronal function, brain inflammation and brain oxidative stress. Thus, PDE10A could be a probable target for pharmacological interventions and furthering our understanding of ASD pathogenesis.

Comorbid anxiety-like behavior in a rat model of colitis is mediated by an upregulation of corticolimbic fatty acid amide hydrolase

Peripheral inflammatory conditions, including those localized to the gastrointestinal tract, are highly comorbid with psychiatric disorders such as anxiety and depression. These behavioral symptoms are poorly managed by conventional treatments for inflammatory diseases and contribute to quality of life impairments. Peripheral inflammation is associated with sustained elevations in circulating glucocorticoid hormones, which can modulate central processes, including those involved in the regulation of emotional behavior. The endocannabinoid (eCB) system is exquisitely sensitive to these hormonal changes and is a significant regulator of emotional behavior. The impact of peripheral inflammation on central eCB function, and whether this is related to the development of these behavioral comorbidities remains to be determined. To examine this, we employed the trinitrobenzene sulfonic acid-induced model of colonic inflammation (colitis) in adult, male, Sprague Dawley rats to produce sustained peripheral inflammation. Colitis produced increases in behavioral measures of anxiety and elevations in circulating corticosterone. These alterations were accompanied by elevated hydrolytic activity of the enzyme fatty acid amide hydrolase (FAAH), which hydrolyzes the eCB anandamide (AEA), throughout multiple corticolimbic brain regions. This elevation of FAAH activity was associated with broad reductions in the content of AEA, whose decline was driven by central corticotropin releasing factor type 1 receptor signaling. Colitis-induced anxiety was reversed following acute central inhibition of FAAH, suggesting that the reductions in AEA produced by colitis contributed to the generation of anxiety. These data provide a novel perspective for the pharmacological management of psychiatric comorbidities of chronic inflammatory conditions through modulation of eCB signaling.

Papaverine ameliorates prenatal alcohol-induced experimental attention deficit hyperactivity disorder by regulating neuronal function, inflammation, and oxidative stress

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder with complex aetiology and phenotypes. Phosphodiesterase10A (PDE10A) has been shown to provide benefits in various brain conditions. We investigated the role of papaverine, a selective PDE10A inhibitor on core phenotypes in prenatal alcohol exposure (PAE) model of ADHD. In order to identify probable mechanisms involved, the effects on several protein markers of neuronal function such as, neuronal survival-BDNF, neuronal transcription factor-pCREB, brain inflammation (IL-6, IL-10, and TNF-α), and brain oxidative stress (TBARS and GSH) were studied in frontal cortex, cerebellum, and striatum. PAE resulting hyper-locomotion, inattention, and anxiety were studied by the use of open-field, y-maze, and elevated plus maze, respectively. Administration of papaverine (15/30 mg kg-1 ) to PAE group of animals resulted in amelioration of hyperactivity, inattention, and anxiety. Also, papaverine resulted in significant increase of the levels in BDNF, pCREB, IL-10, and GSH along with significant decrease of TNF-α, IL-6, and TBARS in different brain areas of PAE group. Papaverine, a selective PDE10A inhibitor rectified behavioural phenotypes associated with ADHD, possibly by altering the protein markers associated with neuronal survival, neuronal transcription factor, brain inflammation, and brain oxidative stress. Implicating PDE10A as a possible target for furthering our understanding of ADHD phenotypes.

The Role of Lipidomics in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a complex neurodevelopmental syndrome commonly diagnosed in early childhood; it is usually characterized by impairment in reciprocal communication and speech, repetitive behaviors, and social withdrawal with loss in communication skills. Its development may be affected by a variety of environmental and genetic factors. Trained physicians diagnose and evaluate the severity of ASD based on clinical evaluations of observed behaviors. As such, this approach is inevitably dependent on the expertise and subjective assessment of those administering the clinical evaluations. There is a need to identify objective biological markers associated with diagnosis or clinical severity of the disorder. Several important issues and concerns exist regarding the diagnostic competence of the many abnormal plasma metabolites produced in the different biochemical pathways evaluated in individuals with ASD. The search for high-performing bio-analytes to diagnose and follow-up ASD development is still a major target in medicine. Dysregulation in the oxidative stress response and proinflammatory processes are major etiological causes of ASD pathogenesis. Furthermore, dicarboxylic acid metabolites, cholesterol-related metabolites, phospholipid-related metabolites, and lipid transporters and mediators are impaired in different pathological conditions that have a role in the ASD etiology. A mechanism may exist by which pro-oxidant environmental stressors and abnormal metabolites regulate clinical manifestations and development of ASD.

Attenuation of neurobehavioural abnormalities by papaverine in prenatal valproic acid rat model of ASD

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with complex aetiology and phenotypes. Phosphodiesterase-10A (PDE10A) inhibition has shown to provide benefits in various brain conditions. We investigated the role of a PDE10A inhibitor, papaverine on core phenotypes in prenatal-valproic acid (Pre-VPA) model of ASD. In order to identify probable mechanisms involved, the effects on several protein markers of neuronal function such as, neurogenesis-DCX, neuronal survival-BDNF, synaptic transmission-synapsin-IIa, neuronal transcription factor-pCREB, neuronal inflammation (IL-6, IL-10 and TNF-α) and neuronal oxidative stress (TBARS and GSH) were studied in frontal cortex, cerebellum, hippocampus and striatum. Pre-VPA induced impairments in social behaviour, presence of repetitive behaviour, hyper-locomotion, anxiety, and diminished nociception were studied in male Albino Wistar rats. Administration of papaverine to Pre-VPA animals resulted in improvements of social behaviour, corrected repetitive behaviour, anxiety, locomotor, and nociceptive changes. Also, papaverine resulted in a significant increase in the levels of BDNF, synapsin-IIa, DCX, pCREB, IL-10 and GSH along with significant decrease in TNF-α, IL-6 and TBARS in different brain areas of Pre-VPA group. Finally, high association between behavioural parameters and biochemical parameters was observed upon Pearson's correlation analysis. Papaverine, administration rectified core behavioural phenotype of ASD, possibly by altering protein markers associated with neuronal survival, neurogenesis, neuronal transcription factor, neuronal transmission, neuronal inflammation, and neuronal oxidative stress. Implicating PDE10A as a possible target for furthering our understanding of ASD phenotypes.

Dapagliflozin improves behavioral dysfunction of Huntington's disease in rats via inhibiting apoptosis-related glycolysis

AIMS

Huntington's disease is a rare neurodegenerative disorder which is associated with defected glucose metabolism with consequent behavioral disturbance including memory and locomotion. 3-nitropropionic acid (3-NP) can cause, in high single dose, an acute striatal injury/Huntington's disease. Dapagliflozin, which is one of the longest duration of action of SGLTIs family, may be able to diminish that injury and its resultant behavioral disturbances.

MATERIAL AND METHODS

Forty rats were divided into four groups (n = 10 in each group): normal control group (CTRL), dapagliflozin (CTRL + DAPA) group, 3-nitropropionic acid (3-NP) group, and dapagliflozin plus 3-nitropropionic acid (DAPA + 3-NP) group. Behavioral tests (beam walking test, hanging wire test, limb withdrawal test, Y-maze spontaneous alteration, elevated plus maze) were performed with evaluating neurological scoring. In striatum, neurotransmitters (glutamate, aspartate, GABA, ACh and AChE activity) were measured. In addition, apoptosis and glycolysis markers (NF-κB, Cyt-c, lactate, HK-II activity, P53, calpain, PEA15 and TIGAR) were determined. Inflammation (IL-1β, IL-6, IL-8 and TNF-α) and autophagy (beclin-1, LC3 and DRAM) indicators were measured. Additionally, histopathological screening was conducted.

KEY FINDINGS

3-Nitropropionic acid had the ability to perturb the neurotransmission which was reflected in impaired behavioral outcome. All of glycolysis, apoptosis and inflammation markers were elevated after 3-NP acute intoxication but autophagy parameters, except DRAM, were reduced. However, DAPA markedly reversed the abovementioned parameters.

SIGNIFICANCE

Dapagliflozin demonstrated anti-glycolytic, anti-apoptotic, anti-inflammatory and autophagic effects on 3-NP-damaged striatal cells and promoted the behavioral outcome.

Relationship between the effect of polyunsaturated fatty acids (PUFAs) on brain plasticity and the improvement on cognition and behavior in individuals with autism spectrum disorder

Objective: This work aimed to compile information about the neuronal processes in which polyunsaturated fatty acids (PUFAs) could modulate brain plasticity, in order to analyze the role of nutritional intervention with the ω-3 and ω-6 fatty acids as a therapeutic strategy for the Autism Spectrum Disorder (ASD)-related signs and symptoms.Methods: We reviewed different articles reporting the effect of PUFAS on neurite elongation, membrane expansion, cytoskeleton rearrangement and neurotransmission, considering the ASD-related abnormalities in these processes.Results: In accordance to the reviewed studies, it is clear that ASD is one of the neurological conditions associated with an impairment in neuronal plasticity; therefore, PUFAs-rich diet improvements on cognition and behavioral deficits in individuals with autism, could be involved with the regulation of neuronal processes implicated in the atypical brain plasticity related with this neurodevelopmental disorder.Discussion: The behavioral and cognitive improvement observed in individuals with ASD after PUFAs treatment might underlie, at least in part, in the ability of ω-3 and ω-6 fatty acids to induce neurite outgrowth, probably, through the dynamic regulation of the neuronal cytoskeleton along with the expansion of neuronal membranes. Furthermore, it might also be associated with an enhancement of the efficacy of synaptic transmission and the modulation of neurotransmitters release.

Propionic acid induced behavioural effects of relevance to autism spectrum disorder evaluated in the hole board test with rats

Autism spectrum disorders (ASD) are a set of neurodevelopmental disorders characterized by abnormal social interactions, impaired language, and stereotypic and repetitive behaviours. Among genetically susceptible subpopulations, gut and dietary influences may play a role in etiology. Propionic acid (PPA), produced by enteric gut bacteria, crosses both the gut-blood and the blood-brain barrier. Previous research has demonstrated that repeated intracerebroventricular (ICV) infusions of PPA in adult rats produce behavioural and neuropathological changes similar to those seen in ASD patients, including hyperactivity, stereotypy, and repetitive movements. The current study examined dose and time related changes of exploratory and repetitive behaviours with the use of the hole-board task. Adult male Long-Evans rats received ICV infusions twice a day, 4 h apart, of either buffered PPA (low dose 0.052 M or high dose 0.26 M, pH 7.5, 4 μL/infusion) or phosphate buffered saline (PBS, 0.1 M) for 7 consecutive days. Locomotor activity and hole-poke behaviour were recorded daily in an automated open field apparatus (Versamax), equipped with 16 open wells, for 30 min immediately after the second infusion. In a dose dependent manner PPA infused rats displayed significantly more locomotor activity, stereotypic behaviour and nose-pokes than PBS infused rats. Low-dose PPA animals showed locomotor activity levels similar to those of PBS animals at the start of the infusion schedule, but gradually increased to levels comparable to those of high-dose PPA animals by the end of the infusion schedule, demonstrating a dose and time dependent effect of the PPA treatments.

Behavioural and brain ultrastructural changes following the systemic administration of propionic acid in adolescent male rats. Further development of a rodent model of autism

Short chain fatty acids, produced as gut microbiome metabolites but also present in the diet, exert broad effects in host physiology. Propionic acid (PPA), along with butyrate and acetate, plays a growing role in health, but also in neurological conditions. Increased PPA exposure in humans, animal models and cell lines elicit diverse behavioural and biochemical changes consistent with organic acidurias, mitochondrial disorders and autism spectrum disorders (ASD). ASD is considered a disorder of synaptic dysfunction and cell signalling, but also neuroinflammatory and neurometabolic components. We examined behaviour (Morris water and radial arm mazes) and the ultrastructure of the hippocampus and medial prefrontal cortex (electron microscopy) following a single intraperitoneal (i.p.) injection of PPA (175 mg/kg) in male adolescent rats. PPA treatment showed altered social and locomotor behaviour without changes in learning and memory. Both transient and enduring ultrastructural alterations in synapses, astro- and microglia were detected in the CA1 hippocampal area. Electron microscopic analysis showed the PPA treatment significantly decreased the total number of synaptic vesicles, presynaptic mitochondria and synapses with a symmetric active zone. Thus, brief systemic administration of this dietary and enteric short chain fatty acid produced behavioural and dynamic brain ultrastructural changes, providing further validation of the PPA model of ASD.

Bee pollen and propolis improve neuroinflammation and dysbiosis induced by propionic acid, a short chain fatty acid in a rodent model of autism

BACKGROUND

Neuroinflammation plays a major role in the pathogenesis of autism because the cytokine levels are typically disturbed in the brain in autistic patients. Prebiotics-rich diet maintains the healthy gut microbiota and hence can regulate the neuroinflammation indirectly. The study aimed to investigate the role of bee pollen and propolis in ameliorating neuroinflammation, including cytokine levels, in an animal model of autism.

METHODS

Hamsters were classified as four groups: Group I, control; Group II, autistic model/animals treated with 250 mg propionic acid (PPA)/kg body weight (BW)/day for 3 days; Group III, animals treated with bee pollen at a dose of 250 mg/kg BW/day for 4 weeks; and Group IV, animals treated with propolis at a dose of 250 mg/kg BW/day for 4 weeks. Neuroinflammatory responses were evaluated using the levels of interferon γ (IFN-γ), interleukin 1 alpha (IL-1α), IL-6, IL-10, IL-12 (p70), vascular endothelial growth factor (VEGF), and tumor necrosis factor α (TNFα).

RESULTS

Significant decrease of IL-10 (P<0.026), VEGF (P<0.005), and TNFα(P<0.005) levels and increased IL-1α (P<0.032), IL-6(P<0.028), and IFN-γ (P<0.013) levels were observed between the four studied groups. The neurotoxic effects of PPA was clearly presented as much higher IL-6, as pro-inflammatory cytokine (P<0.05), concomitant with much lower IL-10, as anti-inflammatory cytokine(P<0.015) compared to controls. Both bee pollen and propolis were effective in ameliorating the neurotoxic effects of PPA demonstrating non-significant changes of IL-6 and IL-10 when compared to control healthy hamsters.

CONCLUSIONS

Our findings indicate that both bee pollen and propolis protect against neuroinflammation in the rodent model of autism. However, further studies are needed to investigate the clinical benefits of prebiotics-rich diet in neurodevelopmental disorders, such as autism.

Beneficial effects of pioglitazone, a selective peroxisome proliferator-activated receptor-γ agonist in prenatal valproic acid-induced behavioral and biochemical autistic like features in Wistar rats

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder in children. It is diagnosis by two main behavioral phenotypes i.e. social-communication impairments and repetitive behavior. ASD is complex disorder with unsolved etiology due to multiple genes involvement, epigenetic mechanism and environmental factors. Valproic acid (VPA), a teratogen is known to induce characteristic features related to ASD in rodents. Numerous studies suggest the potential therapeutic effects of peroxisome proliferator-activated receptor-gamma (PPAR-γ) in different brain disorders. This research evaluates the utility of selective agonist of PPAR-γ, pioglitazone in prenatal VPA induced experimental ASD symptomatology in Wistar rats. The prenatal administration of VPA has induced social impairment, repetitive behavior, hyperlocomotion, anxiety and low exploratory activity in rats. Also, prenatal VPA-treated rats have shown higher levels of oxidative stress (increased in thiobarbituric acid reactive species, and decreased in reduced glutathione level) and inflammation (increased in interleukin-6, tumor necrosis factor-alpha and decreased in interleukin-10) in the cerebellum, brainstem and prefrontal cortex. Treatment with pioglitazone significantly attenuated the prenatal VPA-induced social impairment, repetitive behavior, hyperactivity, anxiety and low exploratory activity. Furthermore, pioglitazone also reduced the prenatal VPA-induced oxidative stress and neuroinflammation in aforementioned brain regions. Hence, it may be concluded that pioglitazone may provide neurobehavioral and biochemical benefits in prenatal VPA-induced autistic phenotypes in rats.