As a prevalent neurodevelopmental disease, whether ASD (autism spectrum disorder) can be ameliorated by the early use of a single microbe remains unknown. Here we used a lactobacillus strain, Lacticaseibacillus rhamnosus GR-1 (LGR-1), for prenatal intervention in autism-like mice with either environmental or idiopathic origins by exclusively administering to the pregnant dams at a dose of 109/mouse/day, followed by offspring behavioral assessment with 3-chamber trial and marble burying test. The results revealed that LGR-1 prevented the occurrence of autism-like symptoms, as evidenced by the improved behaviors and restored E/I (excitatory-inhibitory) balance in the prefrontal cortex of male pups. In parallel, the offspring microbiome was reshaped by LGR-1 treatment, probably mediated by the vertical transmission of maternal microbiome, with its roles further unraveled by fecal microbiota transplant and cross-fostering experiments. In addition to gut commensals, the LGR-1-shaping vaginal microbiota also contributed to the establishment of “beneficial” microbiome. Regarding key taxa in offspring, Akkermansia muciniphila was influenced by LGR-1 and exerted impact on behaviors via pathways related to IL-17-producing lymphocytes. Our findings demonstrate that prenatal microbial administration protects offspring against autism-like behavioral phenotypes through microbiome transmission, highlighting a potential microbe-based therapeutic avenue to mitigate ASD risk.
Repetitive transcranial magnetic stimulation (rTMS) improves cognition in Alzheimer’s disease (AD), yet its biomarker and neuroplasticity effects remain unclear. Cognitive scale scores, plasma biomarker levels, and resting-state fMRI brain network in AD patients were analyzed before and after a 14-day 20 Hz rTMS intervention. The results demonstrated that rTMS intervention significantly improved cognitive performance (MMSE: Z = − 2.863, q = 0.017; MoCA: t = − 6.137, q < 0.001; RAVLT_I: t = − 3.436, q = 0.011) and reduced neuropsychiatric symptoms (NPI: Z = − 2.547, q = 0.037; HAMD: Z = − 3.472, q = 0.009). A 9.4
Royal jelly (RJ) has long been considered a crucial dietary component in dictating caste differentiation in honeybees. As a nutritional additive, royal jelly imparts a broad range of benefits to mammals and humans; however, its precise impact on the social hierarchy of these advanced animals is not yet fully understood. This study aims to determine whether the benefits of royal jelly can be transferred to rats to alter their social ranks and uncover the underlying mechanisms. A submissive model was established by inducing dysbiosis in rats, via the persistent exposure of vancomycin. Royal jelly at a dose of 2.5 g/kg was daily administered to the subject rats during postnatal weeks (PNW) 6 and 7. At the end of the intervention, animals were subjected to agonistic, water and tube competition tests, in order to assess their dominance status. As revealed by the results, the RJ treatment significantly improved the social rank of the dysbiotic rats, demonstrating that RJ can elicit positive effect on the social behaviors (caused by dysbiosis) of rats. All behavioral paradigms yielded consistent results, with no notable differences in body weight or anxiety levels. Regarding gut microbiome, vancomycin exposure caused the dysbiosis of the subject rats, which was partially reversed by treatment with royal jelly. Specifically, the intestinal presence of Proteobacteria was profoundly attenuated by the RJ supplementation, resulting in a comparable level with the intact/dominant rats. At the genus level, both Escherichia and Clostridium displayed similar dynamics in relation to Proteobacteria, implying their involvement with the RJ-mediated dominance switching. Transcriptomic analysis in the medial prefrontal context showed that the expression of a broad range of genes was influenced by RJ intake, embodying various pathways related to neuronal transmission such as neuroactive ligan-receptor interaction, the synaptic vesicle cycle, etc. By virtue of correlation analysis, Escherichia, Akkermansia and Clostridium were strongly associated with a set of gene modules around gastrin releasing peptide (Grp) and signaling pathways around Rps6ka3, establishing an intrinsic gut-brain communication. Furthermore, the infection trials of Escherichia significantly degraded the social ranks of the RJ-remedied rats in tube tests, while a series of cerebral genes like Grpr and Grpel1, as well as prefrontal spine density, were concordantly altered, underscoring the critical role of the gut-brain link in deciding the outcomes of the dyadic contests. In summary, this is an intriguing example of how royal jelly can influence the social ranks of mammals, emphasizing the importance of microbe-host interaction in mediating this species-spanning function of royal jelly in shaping social hierarchy.
Background: The aim of this study is to interrogate the prophylactic effect of probiotic on the lead-induced spatial memory impairment, as well as the underlying mechanisms based on gut microbiota.Methods: Rats were exposed postnatally to 100 ppm of lead acetate during lactation (from postnatal day 1 to 21), to establish the memory deficits model. A probiotic bacterium, namely Lacticaseibacillus rhamnosus, was administered by drinking into pregnant rats with a dosage of 109 CFU/rat/day till birth. At postnatal week 8 (PNW8), the rats were subjected to Morris water maze and Y-maze test, with fecal samples collected for 16S rRNA sequencing. Besides, the inhibitory effect of Lb. rhamnosus on Escherichia coli was carried out in bacterial co-culture.Results: Female rats prenatally exposed to probiotic improved their performances in the behavioral test, indicating that probiotic could protect rats from memory deficits caused by postnatal lead exposure. This bioremediation activity varies depending on the intervention paradigm used. As revealed by microbiome analysis, although administered in a distinct period from lead exposure, Lb. rhamnosus further changed the microbial structure disrupted by lead exposure, suggesting an effective transgenerational intervention. Of note, gut microbiota, represented by Bacteroidota, varied greatly depending on the intervention paradigm as well as the developmental stage. The concerted alterations were revealed between some keystone taxa and behavioral abnormality, including lactobacillus and E. coli. To this end, an in vitro co-culture was created to demonstrate that Lb. rhamnosus could inhibit the growth of E. coli with direct contact, which is dependent on the growth condition under study. In addition, in vivo infection of E. coli O157 aggravated memory dysfunction, which could also be rescued by probiotic colonization.Conclusions: Early probiotic intervention could prevent organisms from lead-induced memory decline in later life through reprogramming gut microbiota and inhibiting E. coli, providing a promising approach to ameliorate the cognitive damage with environmental origins.
Lead (Pb) exposure during early life has been associated with an increased risk of neurodevelopmental disorders, including learning and memory deficits. The intestinal flora, via the microbiome–gut–brain axis, could play a significant role in the nervous system. However, the effects of probiotics on ameliorating Pb-induced learning and memory deficits are still unclear. In this study, we showed that adolescent Pb exposure (150 ppm) for 2 months impaired spatial learning and memory ability, accompanied by the decreasing diversity of gut microbiota, and the decreasing abundance of Lactobacillus at the genus level. Surprisingly, administration of the Lactobacillus rhamnosus GR-1 (1010 organisms/rat/day), not L. rhamnosus LGG or Lactobacillus reuteri RC-14, reversed learning and memory deficits induced by Pb exposure. Meanwhile, administration of the L. rhamnosus GR-1 increased the diversity of the gut microbiota composition and partially normalized the genus level of Lactobacillus, Parabacteroides, Enterococcus, and Akkermansia in Pb-exposed rats. Notably, supplementation of L. rhamnosus GR-1 decreased the gut permeability of Pb-exposed rats, reduced proinflammatory cytokines [interleukin-1β (IL-1β) and IL-6] expression, and promoted anti-inflammatory cytokines [granulocyte colony-stimulating factor (G-CSF)] expression. Interestingly, neural cell treatment with G-CSF rescued Pb-induced neurotoxicity. In general, L. rhamnosus GR-1 supplementation recovered the Pb-induced loss of intestinal bacteria (Lactobacillus), which may have reversed the damage to learning and memory ability. Collectively, our findings demonstrate an unexpectedly pivotal role of L. rhamnosus GR-1 in Pb-induced cognitive deficits and identify a potential probiotic therapy for cognitive dysfunction during early life.
Social dominance is a ubiquitous phenomenon among social animals, including humans. To date, individual attributes leading to dominance (after a contest) remain largely elusive. Here, we report that socially dominant rats can be distinguished from subordinates based on their intestinal microbiota. When dysbiosis is induced, rats are predisposed to a subordinate state, while dysbiotic rats reclaim social dominance following microbiota transplantation. Winning hosts are characterized by core microbes, a majority of which are associated with butyrate production, and the sole colonization of Clostridium butyricum is sufficient to restore dominance. Regarding molecular aspects, a histone deacetylase, HDAC2, is responsive to microbial status and mediates competition outcome; however, this occurs only in a restricted population of cells in the medial prefrontal cortex (mPFC). Furthermore, HDAC2 acts by modulating synaptic activity in mPFC. Together, these findings uncover a link between commensals and host dominance, providing insight into the gut-brain mechanisms underlying dominance determination.
Depressive disorder (DD) is associated with N6-methyladenosine (m6A) hypermethylation. This study sought to explore the molecular mechanism of Methyltransferase-like 3 (METTL3) in cognitive deficits of chronic unpredictable mild stress (CUMS)-treated rats and provide novel targets for DD treatment. A DD rat model was established via CUMS treatment. Cognitive deficits were assessed via body weighing and behavioral tests. METTL3, microRNA (miR)-221-3p, pri-miR-221, GRB2-associated binding protein 1 (Gab1) expressions in hippocampal tissues were detected via RT-qPCR and Western blotting. m6A, DiGeorge syndrome critical region gene 8 (DGCR8)-bound pri-miR-221 and pri-miR-221 m6A levels were measured. The binding relationship between miR-221-3p and Gab1 was testified by dual-luciferase and RNA pull-down assays. Rescue experiments were designed to confirm the role of miR-221-3p and Gab1. METTL3 was highly expressed in CUMS rats, and silencing METTL3 attenuated cognitive deficits of CUMS rats. METTL3-mediated m6A modification facilitated processing and maturation of pri-miR-221 via DGCR8 to upregulate miR-221-3p. miR-221-3p targeted Gab1. miR-221-3p overexpression or Gab1 downregulation reversed the role of silencing METTL3 in CUMS rats. Overall, METTL3-mediated m6A modification facilitated processing and maturation of pri-miR-221 to upregulate miR-221-3p and then inhibit Gab1, thereby aggravating cognitive deficits of CUMS rats.
Macrophages are the main intrinsic immune cells in the cochlea; they can be activated and play a complicated role after cochlear injury. Many studies have shown that the number of macrophages and their morphological characteristics within the major cochlear partitions undergo significant changes under various pathological conditions including acoustic trauma, ototoxic drug treatment, age-related cochlear degeneration, selective hair cell (HC) and spiral ganglion neuron (SGN) elimination, and surgery. However, the exact role of these macrophages after cochlear injury is still unclear. Regulating the migration and activity of macrophages may be a therapeutic approach to reduce the risk or magnitude of trauma-induced hearing loss, and this review highlights the role of macrophages on the peripheral auditory structures of the cochlea and elucidate the mechanisms of macrophage injury and the strategies to reduce the injury by regulating macrophage.
Chronic lead exposure is associated with the development of neurodegenerative diseases, characterized by the long-term memory decline. However, whether this pathogenesis could be prevented through adjusting gut microbiota is not yet understood. To address the issue, pregnant rats and their female offspring were treated with lead (125 ppm) or separately the extra probiotics (1010 organisms/rat/day) till adulthood. For results, memory dysfunction was alleviated by the treatment of multispecies probiotics. Meanwhile, the gut microbiota composition was partially normalized against lead-exposed rats, which in turn mediated the memory repairment via fecal transplantation trials. In the molecular aspect, the decreased H3K27me3 (trimethylation of histone H3 Lys 27) in the adult hippocampus was restored with probiotic intervention, an epigenetic event mediated by EZH2 (enhancer of zeste homolog 2) at early developmental stage. In a neural cellular model, EZH2 overexpression showed the similar rescue effect with probiotics, whereas its blockade led to the neural re-damages. Regarding the gut-brain inflammatory mediators, the disrupted IL-6 (interleukin 6) expression was resumed by probiotic treatment. Intraperitoneal injection of tocilizumab, an IL-6 receptor antagonist, upregulated the hippocampal EZH2 level and consequently alleviated the memory injuries. In conclusion, reshaping gut microbiota could mitigate memory dysfunction caused by chronic lead exposure, wherein the inflammation-hippocampal epigenetic pathway of IL-6-EZH2-H3K27me3, was first proposed to mediate the studied gut-brain communication. These findings provided insight with epigenetic mechanisms underlying a unique gut-brain interaction, shedding light on the safe and non-invasive treatment of neurodegenerative disorders with environmental etiology.
Lead exposure continues to threaten human health in a worldwide perspective. Among the multiple target organs affected by lead, central nervous system (CNS) pervades in the adverse consequences by chronic lead exposure, leading to a variety of neurotoxic manifestations and neurological disorders. The epigenetic machinery plays a vital role in the control of key neural functions, particularly neuronal development. Faulty epigenetic gene regulation can have marked deleterious effect on the developing brain that can last for an entire lifespan. Mounting evidence suggests that lead exposure can pose detrimental effect on CNS through these epigenetic mechanisms. And this chapter reviews the current understandings of concrete epigenetic forms, exemplified by DNA methylation, histone modification, and ncRNAs, responding to lead exposure and moderating the consequent neurotoxicity. In addition, Alzheimer’s disease (AD) is presented as a typical instance to explain how environmental lead exposure results in the occurrence of AD in an “early exposure, late onset” fashion. A future perspective, highlighting additional forms of epigenetic elements as well as interactive actions among different molecules, was also proposed. In summary, epigenetics was substantially implicated in regulating lead neurotoxicity.
Environmental lead (Pb) exposure is closely associated with pathogenesis of a range of neurological disorders, including Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS), attention deficit/hyperactivity disorder (ADHD), etc. Epigenetic machinery modulates neural development and activities, while faulty epigenetic regulation contributes to the diverse forms of CNS (central nervous system) abnormalities and diseases. As a potent epigenetic modifier, lead is thought to cause neurological disorders through modulating epigenetic mechanisms. Specifically, increasing evidence linked aberrant DNA methylations, histone modifications as well as ncRNAs (non-coding RNAs) with AD cases, among which circRNA (circular RNA) stands out as a new and promising field for association studies. In 23-year-old primates with developmental lead treatment, Zawia group discovered a variety of epigenetic changes relating to AD pathogenesis. This is a direct evidence implicating epigenetic basis in lead-induced AD animals with an entire lifespan. Additionally, some epigenetic molecules associated with AD etiology were also known to respond to chronic lead exposure in comparable disease models, indicating potentially interlaced mechanisms with respect to the studied neurotoxic and pathological events. Of note, epigenetic molecules acted via globally or selectively influencing the expression of disease-related genes. Compared to AD, the association of lead exposure with other neurological disorders were primarily supported by epidemiological survey, with fewer reports connecting epigenetic regulators with lead-induced pathogenesis. Some pharmaceuticals, such as HDAC (histone deacetylase) inhibitors and DNA methylation inhibitors, were developed to deal with CNS disease by targeting epigenetic components. Still, understandings are insufficient regarding the cause–consequence relations of epigenetic factors and neurological illness. Therefore, clear evidence should be provided in future investigations to address detailed roles of novel epigenetic factors in lead-induced neurological disorders, and efforts of developing specific epigenetic therapeutics should be appraised.
Graphene consists of two-dimensional sp2-bonded carbon sheets, a single or a few layers thick, which has attracted considerable interest in recent years due to its good conductivity and biocompatibility. Three-dimensional graphene foam (3DG) has been demonstrated to be a robust scaffold for culturing neural stem cells (NSCs) in vitro that not only supports NSCs growth, but also maintains cells in a more active proliferative state than 2D graphene films and ordinary glass. In addition, 3DG can enhance NSCs differentiation into astrocytes and especially neurons. However, the underlying mechanisms behind 3DG's effects are still poorly understood. Metabolism is the fundamental characteristic of life and provides substances for building and powering the cell. Metabolic activity is tightly tied with the proliferation, differentiation, and self-renewal of stem cells. This study focused on the metabolic reconfiguration of stem cells induced by culturing on 3DG. This study established the correlation between metabolic reconfiguration metabolomics with NSCs cell proliferation rate on different scaffold. Several metabolic processes have been uncovered in association with the proliferation change of NSCs. Especially, culturing on 3DG triggered pathways that increased amino acid incorporation and enhanced glucose metabolism. These data suggested a potential association between graphene and pathways involved in Parkinson's disease. Our work provides a very useful starting point for further studies of NSC fate determination on 3DG.
Isotropic inverse opal structures have been extensively studied for the ability to manipulate cell behaviors such as attachment, migration, and spheroid formation. However, their use in regulate the behaviors of neural stem cells has not been fully explored, besides, the isotropic inverse opal structures usually lack the ability to induce the oriented cell growth which is fundamental in neural regeneration based on neural stem cell therapy. In this paper, the anisotropic inverse opal substrates were obtained by mechanically stretching the poly (vinylidene fluoride) (PVDF) inverse opal films. The anisotropic inverse opal substrates possessed good biocompatibility, optical properties and anisotropy, provided well guidance for the formation of neural spheroids, the alignment of neural stem cells, the differentiation of neural stem cells, the oriented growth of derived neurons and the dendritic complexity of the newborn neurons. Thus, we conclude that the anisotropic inverse opal substrates possess great potential in neural regeneration applications.
Inherited hearing loss is associated with gene mutations that result in sensory hair cell (HC) malfunction. HC structure is defined by the cytoskeleton, which is mainly composed of actin filaments and actin-binding partners. LIM motif-containing protein kinases (LIMKs) are the primary regulators of actin dynamics and consist of two members: LIMK1 and LIMK2. Actin arrangement is directly involved in the regulation of cytoskeletal structure and the maturation of synapses in the central nervous system, and LIMKs are involved in structural plasticity by controlling the activation of the actin depolymerization protein cofilin in the olfactory system and in the hippocampus. However, the expression pattern and the role of LIMKs in mouse cochlear development and synapse function also need to be further studied. We show here that the Limk genes are expressed in the mouse cochlea. We examined the morphology and the afferent synapse densities of HCs and measured the auditory function in Limk1 and Limk2 double knockout (DKO) mice. We found that the loss of Limk1 and Limk2 did not appear to affect the overall development of the cochlea, including the number of HCs and the structure of hair bundles. There were no significant differences in auditory thresholds between DKO mice and wild-type littermates. However, the expression of p-cofilin in the DKO mice was significantly decreased. Additionally, no significant differences were found in the number or distribution of ribbon synapses between the DKO and wild-type mice. In summary, our data suggest that the Limk genes play a different role in the development of the cochlea compared to their role in the central nervous system.
Objective: Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive cognitive decline with loss of memory. The objective of this study was to investigate the role and regulatory mechanism of lncRNA-ATB in regulating amyloid-beta-induced neurotoxicity in neuronal PC12 cells. Material and methods: The expression levels of lncRNA-ATB in cerebrospinal fluid (CSF) and serum of patients with Alzheimer's disease (AD) were determined. In addition, PC12 cells were incubated with 20 mu M A beta(25-35) to induce cell injury. The lncRNA-ATB expression in A beta 25-35-treated PC12 cells was also determined. Moreover, the effects of lncRNA-ATB suppression on A beta 25-35-induced PC12 cell injury were investigated by assessing cell viability, apoptosis, cytotoxicity, and oxidative stress (intracellular Ca2+ and ROS concentrations and JC-1 mitochondrial membrane potential). Moreover, the regulatory relationships between lncRNA-ATB and miR-200 were explored, as well as the targets of miR-200 were identified. Results: The results showed that lncRNA-ATB was increased expressed in the CSF and serum of patients with AD. A beta(25-35)-induced injury in PC12 cells and increased the expression of lncRNA-ATB. Suppression of lncRNA-ATB alleviated A beta 25-35-induced PC12 cell injury. Further studies showed that miR-200 was negatively regulated by lncRNA-ATB. Suppression of lncRNA-ATB alleviated A beta(25-35) injury by regulation of miR-200. Moreover, miR-200 negatively regulated ZNF217 expression and ZNF217 was a target of miR-200. Conclusions: Our findings indicate that lncRNA-ATB is highly expressed in AD patients. Suppression of lncRNA-ATB may protect PC12 cells against A beta(25-35)-induced neurotoxicity via regulating miR-200/ZNF217 axis. LncRNA-ATB/miR-200/ZNF217 axis may provide a new insight for preventing AD.