A Novel Retrograde AAV Variant for Functional Manipulation of Cortical Projection Neurons in Mice and Monkeys.

Retrograde adeno-associated viruses (AAVs) are capable of infecting the axons of projection neurons and serve as a powerful tool for the anatomical and functional characterization of neural networks. However, few retrograde AAV capsids have been shown to offer access to cortical projection neurons across different species and enable the manipulation of neural function in non-human primates (NHPs). Here, we report the development of a novel retrograde AAV capsid, AAV-DJ8R, which efficiently labeled cortical projection neurons after local administration into the striatum of mice and macaques. In addition, intrastriatally injected AAV-DJ8R mediated opsin expression in the mouse motor cortex and induced robust behavioral alterations. Moreover, AAV-DJ8R markedly increased motor cortical neuron firing upon optogenetic light stimulation after viral delivery into the macaque putamen. These data demonstrate the usefulness of AAV-DJ8R as an efficient retrograde tracer for cortical projection neurons in rodents and NHPs and indicate its suitability for use in conducting functional interrogations.

A Probiotic Bacillus amyloliquefaciens D-1 Strain Is Responsible for Zearalenone Detoxifying in Coix Semen.

Zearalenone (ZEN) is a mycotoxin produced by Fusarium spp., which commonly and severely contaminate food/feed. ZEN severely affects food/feed safety and reduces economic losses owing to its carcinogenicity, genotoxicity, reproductive toxicity, endocrine effects, and immunotoxicity. To explore efficient methods to detoxify ZEN, we identified and characterized an efficient ZEN-detoxifying microbiota from the culturable microbiome of Pseudostellaria heterophylla rhizosphere soil, designated Bacillus amyloliquefaciens D-1. Its highest ZEN degradation rate reached 96.13% under the optimal condition. And, D-1 can almost completely remove ZEN (90 µg·g-1) from coix semen in 24 h. Then, the D-1 strain can detoxify ZEN to ZEM, which is a new structural metabolite, through hydrolyzation and decarboxylation at the ester group in the lactone ring and amino acid esterification at C2 and C4 hydroxy. Notably, ZEM has reduced the impact on viability, and the damage of cell membrane and nucleus DNA and can significantly decrease the cell apoptosis in the HepG2 cell and TM4 cell. In addition, it was found that the D-1 strain has no adverse effect on the HepG2 and TM4 cells. Our findings can provide an efficient microbial resource and a reliable reference strategy for the biological detoxification of ZEN.

An ultra-compact promoter drives widespread neuronal expression in mouse and monkey brains.

Promoters are essential tools for basic and translational neuroscience research. An ideal promoter should possess the shortest possible DNA sequence with cell-type selectivity. However, whether ultra-compact promoters can offer neuron-specific expression is unclear. Here, we report the development of an extremely short promoter that enables selective gene expression in neurons, but not glial cells, in the brain. The promoter sequence originates from the human CALM1 gene and is only 120 bp in size. The CALM1 promoter (pCALM1) embedded in an adeno-associated virus (AAV) genome directed broad reporter expression in excitatory and inhibitory neurons in mouse and monkey brains. Moreover, pCALM1, when inserted into an all-in-one AAV vector expressing SpCas9 and sgRNA, drives constitutive and conditional in vivo gene editing in neurons and elicits functional alterations. These data demonstrate the ability of pCALM1 to conduct restricted neuronal gene expression, illustrating the feasibility of ultra-miniature promoters for targeting brain-cell subtypes.

Circuit-specific gene therapy reverses core symptoms in a primate Parkinson's disease model.

Parkinson's disease (PD) is a debilitating neurodegenerative disorder. Its symptoms are typically treated with levodopa or dopamine receptor agonists, but its action lacks specificity due to the wide distribution of dopamine receptors in the central nervous system and periphery. Here, we report the development of a gene therapy strategy to selectively manipulate PD-affected circuitry. Targeting striatal D1 medium spiny neurons (MSNs), whose activity is chronically suppressed in PD, we engineered a therapeutic strategy comprised of a highly efficient retrograde adeno-associated virus (AAV), promoter elements with strong D1-MSN activity, and a chemogenetic effector to enable precise D1-MSN activation after systemic ligand administration. Application of this therapeutic approach rescues locomotion, tremor, and motor skill defects in both mouse and primate models of PD, supporting the feasibility of targeted circuit modulation tools for the treatment of PD in humans.

A novel frequency-dependent lattice Boltzmann model with a single force term for electromagnetic wave propagation in dispersive media.

Electromagnetic wave simulation is of pivotal importance in the design and implementation of photonic nano-structures. In this study, we developed a lattice Boltzmann model with a single extended force term (LBM-SEF) to simulate the propagation of electromagnetic waves in dispersive media. By reconstructing the solution of the macroscopic Maxwell equations using the lattice Boltzmann equation, the final form only involves an equilibrium term and a non-equilibrium force term. The two terms are evaluated using the macroscopic electromagnetic variables and the dispersive effect, respectively. The LBM-SEF scheme is capable of directly tracking the evolution of macroscopic electromagnetic variables, leading to lower virtual memory requirement and facilitating the implementation of physical boundary conditions. The mathematical consistency of the LBM-SEF with the Maxwell equations was validated by using the Champman-Enskog expansion; while three practical models were used to benchmark the numerical accuracy, stability, and flexibility of the proposed method.

A high-performance genetically encoded fluorescent indicator for in vivo cAMP imaging.

cAMP is a key second messenger that regulates diverse cellular functions including neural plasticity. However, the spatiotemporal dynamics of intracellular cAMP in intact organisms are largely unknown due to low sensitivity and/or brightness of current genetically encoded fluorescent cAMP indicators. Here, we report the development of the new circularly permuted GFP (cpGFP)-based cAMP indicator G-Flamp1, which exhibits a large fluorescence increase (a maximum ΔF/F0 of 1100% in HEK293T cells), decent brightness, appropriate affinity (a Kd of 2.17 µM) and fast response kinetics (an association and dissociation half-time of 0.20 and 0.087 s, respectively). Furthermore, the crystal structure of the cAMP-bound G-Flamp1 reveals one linker connecting the cAMP-binding domain to cpGFP adopts a distorted ß-strand conformation that may serve as a fluorescence modulation switch. We demonstrate that G-Flamp1 enables sensitive monitoring of endogenous cAMP signals in brain regions that are implicated in learning and motor control in living organisms such as fruit flies and mice.

Targeting thalamic circuits rescues motor and mood deficits in PD mice.

Although bradykinesia, tremor and rigidity are the hallmark motor defects in patients with Parkinson's disease (PD), patients also experience motor learning impairments and non-motor symptoms such as depression1. The neural circuit basis for these different symptoms of PD are not well understood. Although current treatments are effective for locomotion deficits in PD2,3, therapeutic strategies targeting motor learning deficits and non-motor symptoms are lacking4-6. Here we found that distinct parafascicular (PF) thalamic subpopulations project to caudate putamen (CPu), subthalamic nucleus (STN) and nucleus accumbens (NAc). Whereas PF→CPu and PF→STN circuits are critical for locomotion and motor learning, respectively, inhibition of the PF→NAc circuit induced a depression-like state. Whereas chemogenetically manipulating CPu-projecting PF neurons led to a long-term restoration of locomotion, optogenetic long-term potentiation (LTP) at PF→STN synapses restored motor learning behaviour in an acute mouse model of PD. Furthermore, activation of NAc-projecting PF neurons rescued depression-like phenotypes. Further, we identified nicotinic acetylcholine receptors capable of modulating PF circuits to rescue different PD phenotypes. Thus, targeting PF thalamic circuits may be an effective strategy for treating motor and non-motor deficits in PD.

Functional analysis of mutations endowing rAAV2-retro with retrograde tracing capacity.

Recombinant adeno-associated viruses (rAAVs) are widespread vectors in neuroscience research. However, the nearly absent retrograde access to projection neurons hampers their application in functional dissection of neural circuits and in therapeutic intervention. Recently, engineering of the AAV2 capsid has generated an AAV variant, called rAAV2-retro, with exceptional retrograde functionality. This variant comprises a 10-mer peptide insertion at residue 587 and two point mutations (LADQDYTKTA + V708I + N382D). Here, we evaluated the contribution of each mutation to retrograde transport in prefrontal cortex -striatum and amygdala-striatum pathways, respectively. Results showed that disruption of the inserted decapeptide almost completely abolishes the retrograde access to neurons projecting to striatum. Eliminating N382D has little effect on the retrograde functionality. Restoring another mutation V708I, however, even improves its performance in amygdala-striatum pathway. Parallel comparison within same animal further confirms this conflicting effect of V708I. These results demonstrate a pivotal role of decapeptide insertion in gaining the capacity of retrograde transport and highlight a neural circuit-dependent contribution of V708I. It suggests constant and custom engineering of rAAV2-retro might be required to tackle the challenge of tremendous neuronal heterogeneity.

Roles of Gut Microbiota in Pathogenesis of Alzheimer's Disease and Therapeutic Effects of Chinese Medicine.

Alzheimer's disease (AD) is the most common neurodegenerative disease characterized by progressive cognitive impairment. The pathogenesis of AD is complex, and its susceptibility and development process are affected by age, genetic and epigenetic factors. Recent studies confirmed that gut microbiota (GM) might contribute to AD through a variety of pathways including hypothalamic pituitary adrenal axis and inflflammatory and immune processes. CM formula, herbs, and monomer enjoy unique advantages to treat and prevent AD. Hence, the purpose of this review is to outline the roles of GM and its core metabolites in the pathogenesis of AD. Research progress of CMs regarding the mechanisms of how they regulate GM to improve cognitive impairment of AD is also reviewed. The authors tried to explore new therapeutic strategies to AD based on the regulation of GM using CM.

Role of BCLAF-1 in PD-L1 stabilization in response to ionizing irradiation.

Programmed cell death ligand 1 (PD-L1) is a major immunosuppressive checkpoint protein expressed by tumor cells to subvert anticancer immunity. Recent studies have shown that ionizing radiation (IR) upregulates the expression of PD-L1 in tumor cells. However, whether an IR-induced DNA damage response (DDR) directly regulates PD-L1 expression and the functional significance of its upregulation are not fully understood. Here, we show that IR-induced upregulation of PD-L1 expression proceeds through both transcriptional and post-translational mechanisms. Upregulated PD-L1 was predominantly present on the cell membrane, resulting in T-cell apoptosis in a co-culture system. Using mass spectrometry, we identified PD-L1 interacting proteins and found that BCLAF1 (Bcl2 associated transcription factor 1) is an important regulator of PD-L1 in response to IR. BCLAF1 depletion decreased PD-L1 expression by promoting the ubiquitination of PD-L1. In addition, we show that CMTM6 is upregulated in response to IR and participates in BCLAF1-dependent PD-L1 upregulation. Finally, we demonstrated that the ATM/BCLAF1/PD-L1 axis regulated PD-L1 stabilization in response to IR. Together, our findings reveal a novel regulatory mechanism of PD-L1 expression in the DDR.

The Role of Intestinal Dysbacteriosis Induced Arachidonic Acid Metabolism Disorder in Inflammaging in Atherosclerosis.

Background: Aging induced chronic systemic inflammatory response is an important risk factor for atherosclerosis (AS) development; however, the detailed mechanism is yet to be elucidated. Objective: To explore the underlying mechanism of how aging aggravates AS advancement. Methods: A young (five-week-old, YM) and aged group (32-week-old, OM) male apoE-/- mice with a high fat diet were used as models, and age-matched male wild-type C57BL/6J (WT) mice were used as controls. AS lesion size, serum lipid profile, cytokines, and gut microbiota-derived LPS were analyzed after 32 weeks of diet intervention. A correlation analysis between the 16S rRNA sequencing of the feces and serum metabolomics profiles was applied to examine the effect of their interactions on AS. Results: ApoE-/- mice developed severe atherosclerosis and inflammation in the aorta compared to the WT groups, and aged apoE-/- mice suffered from a more severe AS lesion than their younger counterparts and had low-grade systemic inflammation. Furthermore, increased levels of serum LPS, decreased levels of SCFAs production, as well as dysfunction of the ileal mucosal barrier were detected in aged mice compared with their younger counterparts. There were significant differences in the intestinal flora composition among the four groups, and harmful bacteria such as Lachnospiraceae_FCS020, Ruminococcaceae_UCG-009, Acetatifactor, Lachnoclostridium and Lactobacillus_gasseri were significantly increased in the aged apoE-/- mice compared with the other groups. Concurrently, metabolomics profiling revealed that components involved in the arachidonic acid (AA) metabolic pathway such as 20-HETE, PGF2α, arachidonic acid, and LTB4 were significantly higher in the aged AS group than in the other groups. This suggested that metabolic abnormalities and disorders of intestinal flora occurred in AS mice. Conclusions: Aging not only altered the gut microbiome community but also substantially disturbed metabolic conditions. Our results confirm that AA metabolism is associated with the imbalance of the intestinal flora in the AS lesions of aged mice. These findings may offer new insights regarding the role of gut flora disorders and its consequent metabolite changed in inflammaging during AS development.

[Effects of electroacupuncture on skeletal muscle and blood glucose in rats with diabetic amyotrophy].

OBJECTIVE: To explore the effects of electroacupuncture (EA) on skeletal muscle and blood glucose in rats with diabetic amyotrophy. METHODS: Among 40 SD rats, 10 rats were randomly selected into the control group and received no treatment. The remaining 30 rats were treated with intraperitoneal injection of streptozotocin (STZ, 60 mg/kg) to establish diabetes mellitus (DM) model, and then the rats were treated with vascular ligation at right posterior limb to establish amyotrophy model. The rats with diabetic amyotrophy were randomly divided into a model group and an EA group, 10 rats in each group (10 rats were excluded due to unsuccessful model establishment and death). The rats in the EA group was treated with EA at right-side "Yishu (EX-B 3)" "Shenshu (BL 23)" "Zusanli (ST 36)" and "Sanyinjiao (SP 6)", disperse-dense wave, 2 Hz/ 15 Hz, 20 minutes each time, once a day for 3 weeks. Before and after EA treatment, the blood sample was collected from inner canthus and the "glucose oxidase-peroxidase" method was used to detect fasting blood glucose level; ELISA method was used to detect insulin content. At the end of the treatment, HE staining method was used to observe the morphology of ischemic skeletal muscle in the right hindlimb; the real-time PCR method was used to detect the mRNA expression of muscle atrophy F-box (MAFbx), muscle ring finger-1 (MuRF1) and forkhead box O3a (FOXO3a) in the ischemic skeletal muscle tissue of right hindlimb. RESULTS: Before the treatment, the body mass in the model group and EA group was lower than that in the control group (P<0.01); after the treatment, the body mass in the control group was increased, while the body mass in the model group and EA group was decreased (P<0.01). Compared with the control group, the fasting blood glucose was significantly increased and insulin content was significantly decreased in the model group (P<0.01); compared with the model group, the fasting blood glucose was significantly decreased and the insulin content was significantly increased in the EA group after treatment (P<0.01). The muscle fibers of the model group were obviously broken, the number of the nuclei decreased, and the nuclei shrinked or even dissolved; the morphology of the muscle tissue of the EA group after intervention was improved compared with the model group. Compared with the control group, the cross-sectional area of ischemic skeletal muscle cells in the right hindlimb in the model group was decreased (P<0.01); compared with the model group, the cross-sectional area of ischemic skeletal muscle cells in the right hindlimb was increased in EA group (P<0.05). Compared with the control group, the levels of MAFbx, MuRF1 and FOXO3a mRNA in the right hindlimb ischemic skeletal muscle in the model group were increased significantly (P<0.01, P<0.05); compared with the model group, the levels of MAFbx, MuRF1 and FOXO3a mRNA in the EA group were decreased significantly (P<0.05, P<0.01). CONCLUSION: EA may play a role in the treatment of diabetic amyotrophy by inducing FOXO3a to reduce the transcription of MAFbx and MuRF1.

Gasdermin family: a promising therapeutic target for cancers and inflammation-driven diseases.

This review focuses on current advances in researches of gasdermin family. The distinctive expression patterns and biological roles of members in this family were discussed. Most of them exhibit pore-forming activity on cell membranes and are executors for programmed cell death with cytokines release, and play roles in cancers and inflammation-driven diseases. Therefore, they can be used as potential therapeutic targets to treat related diseases.

Prenatal Exposure to Ketamine Leads to Anxiety-Like Behaviors and Dysfunction in Bed Nucleus of Stria Terminalis.

BACKGROUND: Both the clinical and preclinical studies have suggested embryonic or infant exposure to ketamine, a general anesthetic, pose a great threat to the developing brain. However, it remains unclear how ketamine may contribute to the brain dysfunctions. METHODS: A mouse model of prenatal exposure to ketamine was generated by i.m. injection and continuous i.p. infusion of pregnant mice. Open field test and elevated plus maze test were used to analyze the behavioral alterations induced by ketamine. Immunostaining by c-Fos was used to map the neuron activity. Chemogenetic modulation of the neurons was used to rescue the abnormal neuron activity and behaviors. RESULTS: Here we show that mice prenatally exposed to ketamine displayed anxiety-like behaviors during adulthood, but not during puberty. C-Fos immunostaining identified abnormal neuronal activity in Bed Nucleus of the Stria Terminalis, the silencing of which by chemogenetics restores the anxiety-like behaviors. CONCLUSIONS: Taken together, these results demonstrate a circuitry mechanism of ketamine-induced anxiety-like behaviors.

Target of MCC950 in Inhibition of NLRP3 Inflammasome Activation: a Literature Review.

MCC950 has been proposed as a specific small molecule inhibitor that can selectively block NLRP3 inflammasome activation. However, the exact mechanism of its action is still ambiguous. Accumulating investigations imply that chloride efflux-dependent ASC speck oligomerization and potassium efflux-dependent activation of caspase-1 are the two relatively independent, but indispensable events for NLRP3 inflammasome activation. Previous studies suggested that influence of MCC950 on potassium efflux and its consequent events such as interaction between NEK7 and NLRP3 are limited. However, inhibiting chloride intracellular channel-dependent chloride efflux leads to a modification of inflammatory response, which is similar to the function of MCC950. Based on these findings, we shed new insights on the understanding of MCC950 that its function might correlate with chloride efflux, chloride intracellular channels, or other targets that act upstream of chloride efflux.

Knockdown of CLC-3 in the hippocampal CA1 impairs contextual fear memory.

Previous studies support a critical role of hippocampus in contextual fear memory. Structural and functional alterations of hippocampus occur frequently in posttraumatic stress disorders (PTSD). Recent reports reveal that knockout of CLC-3, a member of the CLC family of anion channels and transporters, leads to neuronal degeneration and loss of hippocampus. However, the role of CLC-3 in contextual fear memory remains unknown. Using adenovirus and adeno-associated virus gene transfer to knockdown CLC-3 in hippocampal CA1, we investigate the role of CLC-3 in contextual fear memory. CLC-3 expression is increased in hippocampal CA1 after formation of long-term contextual fear memory. Knockdown of CLC-3 by adenovirus infusion in hippocampal CA1 significantly attenuates the contextual fear memory, reduces spine density, induces defects of excitatory synaptic ultrastructure showed by the decreased PSD length, PSD thickness and active zone length, and impairs L-LTP induction and maintenance. Knockdown of CLC-3 also induces the synaptic NMDAR subunit composition to an increased GluN2A/GluN2B ratio pattern and reduces the activity of CaMKII-α. Furthermore, selectively knockdown of CLC-3 in excitatory neurons by adeno-associated virus driven from CaMKII-α promoter is sufficient to impair long-term contextual fear memory. These findings highlight that CLC-3 in hippocampal CA1 is necessary for contextual fear memory.

Two loci concurrent mutations in non-exclusion parentage cases using 19 STR profiles.

Two loci concurrent mutations in non-exclusion paternity case were reported based on 19 STR loci available from Goldeneye™ DNA ID System 20A (Peoplespot, Beijing, China). When 9508 family trios with Paternity index (PI) threshold of >10,000 was analyzed, 14 families show mutations at two loci. The paternity was confirmed by using an additional 19 STR markers. When the probability of occurrence of two mutations was compared with the expected probability deduced from binomial model, the observed mutational probability was significantly larger than the expectation. However, the characteristics of mutations agree with those reported previously. Our result indicates that larger samples is still need to estimate mutation rates accurately and reveal the relationship between mutations with multiple loci and the characterization of human mutations based on microsatellites.

Maternal Deprivation Enhances Contextual Fear Memory via Epigenetically Programming Second-Hit Stress-Induced Reelin Expression in Adult Rats.

Background: Early-life stress increases the risk for posttraumatic stress disorder. However, the epigenetic mechanism of early-life stress-induced susceptibility to posttraumatic stress disorder in adulthood remains unclear. Methods: Rat pups were exposed to maternal deprivation during postnatal days 1 to 14 for 3 hours daily and treated with the DNA methyltransferase inhibitor zebularine, L-methionine, or vehicle 7 days before contextual fear conditioning, which was used as a second stress and to mimic the reexperiencing symptom of posttraumatic stress disorder in adulthood. Long-term potentiation, dendritic spine density, DNA methyltransferase mRNA, Reelin gene methylation, and Reelin protein expression in the hippocampal CA1 were measured. Results: Maternal deprivation enhanced contextual fear memory in adulthood. Meanwhile, maternal deprivation decreased DNA methyltransferase mRNA and Reelin gene methylation in the hippocampal CA1 on postnatal days 22 and 90. Reelin protein expression was increased in the hippocampal CA1 following contextual fear conditioning in adulthood. Furthermore, compared with rats that experienced maternal deprivation alone, rats also exposed to contextual fear conditioning showed an enhanced induction of hippocampal long-term potentiation and increased dendritic spine density in the hippocampal CA1 following contextual fear conditioning in adulthood. Zebularine pretreatment led to an enhancement of contextual fear memory, hypomethylation of the Reelin gene, and increased Reelin protein expression in adult rats, while L-methionine had the opposite effects. Conclusions: Maternal deprivation can epigenetically program second-hit stress-induced Reelin expression and enhance the susceptibility to contextual fear memory in adulthood. These findings provide a new framework for understanding the cumulative stress hypothesis.

Population structure of Han nationality in Central-Southern China.

Knowledge of population structure is very important for forensic genetics. However, the population substructure in Central-Southern China Han nationality has still not been fully described. In this study, we investigated the genetic diversity of 15 forensic autosomal STR loci from 6879 individuals in 12 Han populations subdivided by administrative provinces in Central-Southern China. The statistical analysis of genetic variation showed that genetic differentiation among these populations was very small with a Fst value of 0.0009. The Discriminant Analysis of Principal Components (DAPC) showed that there were no obvious population clusters in Central-Southern China Han population. In practice, the population structure effect in Central-Southern China Han population can be negligible in forensic identification and paternity testing.

Population data and mutation rates of 19 STR loci in seven provinces from China based on Goldeneye™ DNA ID System 20A.

Short tandem repeat (STR) analysis is a primary tool in forensic casework. Population data and mutation rates of STRs are very important for paternity testing and forensic genetics. However, the population data and mutation rates of STRs in Han nationality based on large samples have still not been fully described in China. In this study, the allelic frequencies, forensic parameters, and mutation rate of 19 STR loci (D19S433, D5S818, D21S11, D18S51, D6S1043, D3S1358, D13S317, D7S820, D16S539, CSFIPO, PentaD, vWA, D8S1179, TPOX, Penta E, TH01, D12S391, D2S1338, and FGA) based on the Goldeneye™ DNA ID System 20A in Southern China Han nationality among seven provinces were investigated. Furthermore, population stratification of Southern China Han nationality among seven provinces was established. The multidimensional scaling (MDS) plot based on genetic distances (Fst) showed that the studied populations can be clustered into two major groups. However, relationships among populations were weak (Fst < 0.0043). A total of 376 cases of mutation were detected from the 19 selected loci in 15,396 meioses. The average mutation rate for the 19 loci was estimated to be 1.3 × 10-3 per meiosis. The mutation was mainly single step; the paternal mutation rate was higher than the maternal; and paternal mutation rate increases with paternal age.