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BioRxiv : the Preprint Server For... Jun 2024In schizophrenia, layer 3 pyramidal neurons (L3PNs) in the dorsolateral prefrontal cortex (DLPFC) are thought to receive fewer excitatory synaptic inputs and to have...
UNLABELLED
In schizophrenia, layer 3 pyramidal neurons (L3PNs) in the dorsolateral prefrontal cortex (DLPFC) are thought to receive fewer excitatory synaptic inputs and to have lower expression levels of activity-dependent genes and of genes involved in mitochondrial energy production. In concert, these findings from previous studies suggest that DLPFC L3PNs are hypoactive in schizophrenia, disrupting the patterns of activity that are crucial for working memory, which is impaired in the illness. However, whether lower PN activity produces alterations in inhibitory and/or excitatory synaptic strength has not been tested in the primate DLPFC. Here, we decreased PN excitability in rhesus monkey DLPFC using adeno-associated viral vectors (AAVs) to produce Cre recombinase-mediated overexpression of Kir2.1 channels, a genetic silencing tool that efficiently decreases neuronal excitability. In acute slices prepared from DLPFC 7-12 weeks post-AAV microinjections, Kir2.1-overexpressing PNs had a significantly reduced excitability largely attributable to highly specific effects of the AAV-encoded Kir2.1 channels. Moreover, recordings of synaptic currents showed that Kir2.1-overexpressing DLPFC PNs had reduced strength of excitatory synapses whereas inhibitory synaptic inputs were not affected. The decrease in excitatory synaptic strength was not associated with changes in dendritic spine number, suggesting that excitatory synapse quantity was unaltered in Kir2.1-overexpressing DLPFC PNs. These findings suggest that, in schizophrenia, the excitatory synapses on hypoactive L3PNs are weaker and thus might represent a substrate for novel therapeutic interventions.
SIGNIFICANCE STATEMENT
In schizophrenia, dorsolateral prefrontal cortex (DLPFC) pyramidal neurons (PNs) have both transcriptional and structural alterations that suggest they are hypoactive. PN hypoactivity is thought to produce synaptic alterations in schizophrenia, however the effects of lower neuronal activity on synaptic function in primate DLPFC have not been examined. Here, we used, for the first time in primate neocortex, adeno-associated viral vectors (AAVs) to reduce PN excitability with Kir2.1 channel overexpression and tested if this manipulation altered the strength of synaptic inputs onto the Kir2.1-overexpressing PNs. Recordings in DLPFC slices showed that Kir2.1 overexpression depressed excitatory (but not inhibitory), synaptic currents, suggesting that, in schizophrenia, the hypoactivity of PNs might be exacerbated by reduced strength of the excitatory synapses they receive.
PubMed: 38915638
DOI: 10.1101/2024.06.12.598658 -
Progress in Neuro-psychopharmacology &... Jun 2024The ventral pallidum (VP) receives its primary inputs from the nucleus accumbens (NAC) and the basolateral amygdala (BLA). We demonstrated recently that in the VP, the...
The ventral pallidum (VP) receives its primary inputs from the nucleus accumbens (NAC) and the basolateral amygdala (BLA). We demonstrated recently that in the VP, the D2 DA receptor (DR) agonist quinpirole dose-dependently facilitates memory consolidation in inhibitory avoidance and spatial learning. In the VP, DR can be found both on NAC and BLA terminals. According to our hypothesis, quinpirole microinjected into the VP can facilitate memory consolidation via modulation of synaptic plasticity on NAC and/or BLA terminals. The effect of intra-VP quinpirole on BLA-VP and NAC shell-VP synapses was investigated via a high frequency stimulation (HFS) protocol. Quinpirole was administered in three doses into the VP of male Sprague-Dawley rats after HFS; controls received vehicle. To examine whether an interaction between the NAC shell and the BLA at the level of the VP was involved, tetrodotoxin (TTX) was microinjected into one of the nuclei while stimulating the other nucleus. Our results showed that quinpirole dose-dependently modulates BLA-VP and NAC shell-VP synapses, similar to those observed in inhibitory avoidance and spatial learning, respectively. The lower dose inhibits BLA inputs, while the larger doses facilitates NAC shell inputs. The experiments with TTX demonstrates that the two nuclei do not influence each others' evoked responses in the VP. Power spectral density analysis demonstrated that independent from the synaptic facilitation, intra-VP quinpirole increases the amplitude of gamma frequency band after NAC HFS, and BLA tonically suppresses the NAC's HFS-induced gamma facilitation. In contrast, HFS of the BLA results in a delayed, transient increase in the amplitude of the gamma frequency band correlating with the LTP of the P1 component of the VP response to BLA stimulation. Furthermore, our results demonstrate that the BLA plays a prominent role in the generation of the delta oscillations: HFS of the BLA leads to a gradually increasing delta frequency band facilitation over time, while BLA inhibition blocks the NAC's HFS induced strong delta facilitation. These findings demonstrate that there is a complex interaction between the NAC shell region and the VP, as well as the BLA and the VP, and support the important role of VP DRs in the regulation of limbic information flow.
PubMed: 38901759
DOI: 10.1016/j.pnpbp.2024.111059 -
Clinical, Cosmetic and Investigational... 2024Rosacea is a chronic inflammatory skin disease that affects a patient's appearance and quality of life. It mainly affects the midface region and presents as erythema,... (Review)
Review
Rosacea is a chronic inflammatory skin disease that affects a patient's appearance and quality of life. It mainly affects the midface region and presents as erythema, flushing, telangiectasia, papules, pustules, and rhinophyma. Despite its prevalence, the precise pathophysiology of rosacea remains unknown, and novel pharmacological therapies are currently under investigation. Tranexamic acid (TA) is a synthetic, lysine-like compound that competitively inhibits fibrinogen production by synthesizing fibrinolytic enzymes. In addition to its popular application in hemorrhage treatment, TA has been used to manage a number of skin conditions, including melasma, chronic urticaria, and angioedema. TA is a better option for melasma treatment. However, the role of TA in treating rosacea has not yet been systematically elucidated. In this study, we reviewed all available literature on the use of TA for rosacea treatment. The included articles examined the therapeutic effects of TA in patients with rosacea, including traditional methods such as oral and topical administration and more novel approaches such as intradermal injections, microneedling, and laser-assisted delivery. Several recent clinical studies demonstrated that TA alleviates rosacea symptoms by restoring the permeability barrier, ameliorating the immune reaction, and inhibiting angiogenesis. In this review, we summarized the function and potential application of TA in rosacea treatment, aiming to facilitate the implementation of clinical applications.
PubMed: 38895607
DOI: 10.2147/CCID.S473598 -
Journal of Clinical Medicine May 2024Sedentary lifestyles, work overload, and lack of regular physical activity are risk factors for spinal pain syndrome. In everyday medical practice, spinal pain syndrome... (Review)
Review
Sedentary lifestyles, work overload, and lack of regular physical activity are risk factors for spinal pain syndrome. In everyday medical practice, spinal pain syndrome of a muscular or myofascial, or non-neurogenic, nature is diagnosed. This problem affects a large group of patients and reaches about 70-80% of spinal pain cases. Usually, one of the primary treatments is with NSAIDs (Non-steroidal Anti-Inflammatory Drugs). In this case, one treatment method that is safe and has no side effects is spinal mesotherapy. This method consists of performing multi-point intradermal microinjections with the administration of drugs or medical devices. Based on a new perspective on the treatment of spinal pathology-the so-called three-stage treatment concept-it is necessary to deal with the risk factor(s) of spinal pain syndrome and reduce or at least modify them (stage I). This is followed by a broadly understood medical therapy, in this case spinal mesotherapy (stage II), which aims to relax tense tissues, improve mobility in the spine and thus reduce pain. As a result, conditions are created for the necessary process, which is rehabilitation in the broadest sense (stage III). Movement therapy, which is crucial in spinal pain syndrome, is performed with less pain, after obtaining better patient mobility. The purpose of this article is to evaluate the role of rehabilitation of patients after spinal mesotherapy in terms of the three-stage treatment concept for spinal pathology.
PubMed: 38892905
DOI: 10.3390/jcm13113195 -
Journal of Pharmacy & Bioallied Sciences Apr 2024Mesotherapy is a popular novel therapeutic modality that delivers intradermal or subcutaneous microinjections of pharmaceutical compounds. Although this novel treatment... (Review)
Review
Mesotherapy is a popular novel therapeutic modality that delivers intradermal or subcutaneous microinjections of pharmaceutical compounds. Although this novel treatment method is used commonly in aesthetic dermatology, there is little information about the details of injections, efficacy, and side effects of mesotherapy in melasma. In this review, we evaluated the efficacy of various types of anti-pigmentation agents used with mesotherapy in the management of melasma.
PubMed: 38882767
DOI: 10.4103/jpbs.jpbs_1192_23 -
PLoS Genetics Jun 2024Tardigrades are small aquatic invertebrates known for their remarkable tolerance to diverse extreme stresses. To elucidate the in vivo mechanisms underlying this...
Tardigrades are small aquatic invertebrates known for their remarkable tolerance to diverse extreme stresses. To elucidate the in vivo mechanisms underlying this extraordinary resilience, methods for genetically manipulating tardigrades have long been desired. Despite our prior success in somatic cell gene editing by microinjecting Cas9 ribonucleoproteins (RNPs) into the body cavity of tardigrades, the generation of gene-edited individuals remained elusive. In this study, employing an extremotolerant parthenogenetic tardigrade species, Ramazzottius varieornatus, we established conditions that led to the generation of gene-edited tardigrade individuals. Drawing inspiration from the direct parental CRISPR (DIPA-CRISPR) technique employed in several insects, we simply injected a concentrated Cas9 RNP solution into the body cavity of parental females shortly before their initial oviposition. This approach yielded gene-edited G0 progeny. Notably, only a single allele was predominantly detected at the target locus for each G0 individual, indicative of homozygous mutations. By co-injecting single-stranded oligodeoxynucleotides (ssODNs) with Cas9 RNPs, we achieved the generation of homozygously knocked-in G0 progeny, and these edited alleles were inherited by G1/G2 progeny. This is the first example of heritable gene editing in the entire phylum of Tardigrada. This establishment of a straightforward method for generating homozygous knockout/knock-in individuals not only facilitates in vivo analyses of the molecular mechanisms underpinning extreme tolerance, but also opens up avenues for exploring various topics, including Evo-Devo, in tardigrades.
Topics: Animals; Tardigrada; CRISPR-Cas Systems; Gene Editing; Parthenogenesis; Homozygote; Female; Gene Knock-In Techniques; Gene Knockout Techniques; Alleles
PubMed: 38870088
DOI: 10.1371/journal.pgen.1011298 -
Animal Models and Experimental Medicine Jun 2024This study aimed to construct and characterize a humanized influenza mouse model expressing hST6GAL1.
BACKGROUND
This study aimed to construct and characterize a humanized influenza mouse model expressing hST6GAL1.
METHODS
Humanized fragments, consisting of the endothelial cell-specific K18 promoter, human ST6GAL1-encoding gene, and luciferase gene, were microinjected into the fertilized eggs of mice. The manipulated embryos were transferred into the oviducts of pseudopregnant female mice. The offspring were identified using PCR. Mice exhibiting elevated expression of the hST6GAL1 gene were selectively bred for propagation, and in vivo analysis was performed for screening. Expression of the humanized gene was tested by performing immunohistochemical (IHC) analysis. Hematologic and biochemical analyses using the whole blood and serum of humanized hST6GAL1 mice were performed.
RESULTS
Successful integration of the human ST6GAL1 gene into the mouse genome led to the overexpression of human SiaT ST6GAL1. Seven mice were identified as carrying copies of the humanized gene, and the in vivo analysis indicated that hST6GAL1 gene expression in positive mice mirrored influenza virus infection characteristics. The IHC results revealed that hST6GAL1 was expressed in the lungs of humanized mice. Moreover, the hematologic and biochemical parameters of the positive mice were within the normal range.
CONCLUSION
A humanized influenza mouse model expressing the hST6GAL1 gene was successfully established and characterized.
PubMed: 38859745
DOI: 10.1002/ame2.12449 -
Cureus May 2024Patterned hair loss (PHL) is a severe hair condition that affects both sexes. Mesotherapy is a treatment that involves microinjecting medications and/or vitamins into... (Review)
Review
Patterned hair loss (PHL) is a severe hair condition that affects both sexes. Mesotherapy is a treatment that involves microinjecting medications and/or vitamins into the middle layer of the skin. Mesotherapy reduces systemic adverse effects by delivering drugs directly to the hair follicle, increasing local bioavailability while lowering systemic exposure. Local side effects and reactions may develop due to mesotherapy. This study systematically evaluated the safety and efficacy of mesotherapy to minoxidil 5%, as well as addressing its limitations, dosing, and technique, with the intent of providing valuable trials and insights for clinicians and patients considering mesotherapy for improved androgenetic alopecia (AGA) outcomes. The literature search carried out by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria yielded 11 relevant studies from an initial pool of 18 articles. These studies covered various aspects of the role of mesotherapy and minoxidil in AGA, including techniques, complications, limitations, and outcomes. In conclusion, available trials and research on mesotherapy and minoxidil demonstrated excellent statistical significance and a high patient satisfaction rate, with the exception of two publications that took into account certain uncommon adverse effects of mesotherapy. However, recent research suggests that a mesotherapy method for alopecia with a low risk of side effects is effective.
PubMed: 38841017
DOI: 10.7759/cureus.59705 -
Molecular Brain Jun 2024Loss-of-function mutations in the progranulin (GRN) gene are an autosomal dominant cause of Frontotemporal Dementia (FTD). These mutations typically result in...
Loss-of-function mutations in the progranulin (GRN) gene are an autosomal dominant cause of Frontotemporal Dementia (FTD). These mutations typically result in haploinsufficiency of the progranulin protein. Grn mice provide a model for progranulin haploinsufficiency and develop FTD-like behavioral abnormalities by 9-10 months of age. In previous work, we demonstrated that Grn mice develop a low dominance phenotype in the tube test that is associated with reduced dendritic arborization of layer II/III pyramidal neurons in the prelimbic region of the medial prefrontal cortex (mPFC), a region key for social dominance behavior in the tube test assay. In this study, we investigated whether progranulin haploinsufficiency induced changes in dendritic spine density and morphology. Individual layer II/III pyramidal neurons in the prelimbic mPFC of 9-10 month old wild-type or Grn mice were targeted for iontophoretic microinjection of fluorescent dye, followed by high-resolution confocal microscopy and 3D reconstruction for morphometry analysis. Dendritic spine density in Grn mice was comparable to wild-type littermates, but the apical dendrites in Grn mice had a shift in the proportion of spine types, with fewer stubby spines and more thin spines. Additionally, apical dendrites of Grn mice had longer spines and smaller thin spine head diameter in comparison to wild-type littermates. These changes in spine morphology may contribute to altered circuit-level activity and social dominance deficits in Grn mice.
Topics: Animals; Dendritic Spines; Prefrontal Cortex; Haploinsufficiency; Progranulins; Mice; Pyramidal Cells; Male; Mice, Inbred C57BL
PubMed: 38840181
DOI: 10.1186/s13041-024-01095-5 -
IBRO Neuroscience Reports Jun 2024The precise cause of autism spectrum disorder (ASD) is not fully understood. Despite the involvement of glutamatergic dysregulation in autism, the specific contribution...
Effect of intrahippocampal microinjection of VU0155041, a positive allosteric modulator of mGluR4, on long term potentiation in a valproic acid-induced autistic male rat model.
The precise cause of autism spectrum disorder (ASD) is not fully understood. Despite the involvement of glutamatergic dysregulation in autism, the specific contribution of mGlu4 receptors to synaptic plasticity remains unclear. Using the positive allosteric modulator VU0155041, we aimed to restore long-term potentiation (LTP) in the perforant path-dentate gyrus (PP-DG) pathway in VPA-induced autistic rat model. High-frequency stimulation was applied to the PP-DG synapse to induce LTP, while the VU0155041 was administered into the DG. Unexpectedly, VU0155041 failed to alleviate the observed LTP reduction in VPA-exposed rats, further resulting in a significant decrease in population spike LTP. This unexpected outcome prompts discussion on the complex nature of mGlu4 receptor modulation, highlighting potential interference with physiological processes underlying synaptic plasticity.
PubMed: 38832089
DOI: 10.1016/j.ibneur.2024.05.005