A Prelimbic Cortex-Thalamus Circuit Bidirectionally Regulates Innate and Stress-Induced Anxiety-Like Behavior.

Anxiety-related disorders respond to cognitive behavioral therapies, which involved the medial prefrontal cortex (mPFC). Previous studies have suggested that subregions of the mPFC have different and even opposite roles in regulating innate anxiety. However, the specific causal targets of their descending projections in modulating innate anxiety and stress-induced anxiety have yet to be fully elucidated. Here, we found that among the various downstream pathways of the prelimbic cortex (PL), a subregion of the mPFC, PL-mediodorsal thalamic nucleus (MD) projection, and PL-ventral tegmental area (VTA) projection exhibited antagonistic effects on anxiety-like behavior, while the PL-MD projection but not PL-VTA projection was necessary for the animal to guide anxiety-related behavior. In addition, MD-projecting PL neurons bidirectionally regulated remote but not recent fear memory retrieval. Notably, restraint stress induced high-anxiety state accompanied by strengthening the excitatory inputs onto MD-projecting PL neurons, and inhibiting PL-MD pathway rescued the stress-induced anxiety. Our findings reveal that the activity of PL-MD pathway may be an essential factor to maintain certain level of anxiety, and stress increased the excitability of this pathway, leading to inappropriate emotional expression, and suggests that targeting specific PL circuits may aid the development of therapies for the treatment of stress-related disorders.

Enhancing high-quality fat survival: A novel strategy using cell-free fat extract.

High-quality fat (HQF) improves the survival rate of fat and volumetric filling compared to traditional Coleman fat. However, this HQF strategy inevitably leads to a significant amount of unused fat being wasted. "CEFFE" (cell-free fat extract) is an acellular aqueous-phase liquid, rich in bioactive proteins. The remaining fat from preparing HQF can be further processed into CEFFE to promote the survival of HQF. HQF was obtained and the remaining fat was processed into CEFFE, then HQF was transplanted subcutaneously in nude mice. Animal studies showed that CEFFE significantly improved the survival rate of HQF. Histological analysis revealed that CEFFE improved the survival rate of HQF, by enhancing cell proliferation activity, reducing apoptosis, increasing angiogenesis, and improving the inflammatory state. Under simulated anaerobic conditions, CEFFE also improved the viability of HQF. In vitro, studies demonstrated that CEFFE enhanced the survival rate of HQF through multiple mechanisms. Transcriptomic analysis and qPCR showed that CEFFE increased the expression of angiogenesis-related genes in ADSCs while enhancing their proliferation-related gene expression and suppressing the expression of three differentiation-related genes. Moreover, functional experiments demonstrated that CEFFE-induced ADSCs exhibited stronger proliferation and adipogenic differentiation abilities. Tube formation and migration assays revealed that CEFFE promoted tube formation and migration of HUVECs, indicating its inherent pro-angiogenic properties. CEFFE facilitated the development of M0 to M2 macrophages, suggesting its role in improving the inflammatory state. This innovative clinical strategy optimizes HQF transplantation strategy, minimizing fat wastage and enhancing the efficiency of fat utilization.

The efficiency of human fat products in wound healing: A systematic review and meta-analysis.

Wound development and healing involve intricate genetic and molecular processes, posing significant clinical management challenges. The objective of this study was to assess commonly used fat extracts' efficacy and safety (autologous fat, stromal vascular fraction and adipose-derived stem cells) in wound healing, particularly for refractory wounds, with the goal of providing evidence in clinical use. After a systematic review, 21 randomised controlled trials were included in our study. Based on the classification of human fat products, our meta-analysis revealed that the use of human fat products could speed healing rate, shorten healing time and achieve more complete healing, with statistically significant differences in outcome indicators when compared to conventional treatments. The analysis of histological findings across various studies indicated that fat extracts can promote epithelialization, collagen deposition and vascularization, thereby facilitating tissue regeneration and reducing inflammatory reactions. There were potential benefits to reducing patient pain levels after using adipose extracts. Furthermore, we analysed and summarised adverse events indicating the safe and effective clinical use of human fat products in wound treatment. Our research findings supported the efficiency of human fat products and demonstrated a high degree of safety in the clinical practice of wound management.

Distinct roles of astroglia and neurons in synaptic plasticity and memory.

Long-term potentiation (LTP) in the hippocampus is the most studied form of synaptic plasticity. Temporal integration of synaptic inputs is essential in synaptic plasticity and is assumed to be achieved through Ca2+ signaling in neurons and astroglia. However, whether these two cell types play different roles in LTP remain unknown. Here, we found that through the integration of synaptic inputs, astrocyte inositol triphosphate (IP3) receptor type 2 (IP3R2)-dependent Ca2+ signaling was critical for late-phase LTP (L-LTP) but not early-phase LTP (E-LTP). Moreover, this process was mediated by astrocyte-derived brain-derived neurotrophic factor (BDNF). In contrast, neuron-derived BDNF was critical for both E-LTP and L-LTP. Importantly, the dynamic differences in BDNF secretion play a role in modulating distinct forms of LTP. Moreover, astrocyte- and neuron-derived BDNF exhibited different roles in memory. These observations enriched our knowledge of LTP and memory at the cellular level and implied distinct roles of astrocytes and neurons in information integration.

PV network plasticity mediated by neuregulin1-ErbB4 signalling controls fear extinction.

Neuroplasticity in the medial prefrontal cortex (mPFC) is essential for fear extinction, the process of which forms the basis of the general therapeutic process used to treat human fear disorders. However, the underlying molecules and local circuit elements controlling neuronal activity and concomitant induction of plasticity remain unclear. Here we show that sustained plasticity of the parvalbumin (PV) neuronal network in the infralimbic (IL) mPFC is required for fear extinction in adult male mice and identify the involvement of neuregulin 1-ErbB4 signalling in PV network plasticity-mediated fear extinction. Moreover, regulation of fear extinction by basal medial amygdala (BMA)-projecting IL neurons is dependent on PV network configuration. Together, these results uncover the local molecular circuit mechanisms underlying mPFC-mediated top-down control of fear extinction, suggesting alterative therapeutic approaches to treat fear disorders.

A Novel Fat Making Strategy With Adipose-Derived Progenitor Cell-Enriched Fat Improves Fat Graft Survival.

BACKGROUND: A low survival rate is one of the main challenges in fat grafting. OBJECTIVES: This study aimed to evaluate whether microfat obtained by a novel strategy promoted the survival and retention of fat grafts. METHODS: A 5-mm-diameter blunt tip cannula with large side holes (~30 mm2/hole) was used to obtain macrofat. A novel strategy based on a newly invented extracorporeal cutting device was then used to cut the macrofat into microfat, which was named adipose-derived progenitor cell enrichment fat (AER fat); Coleman fat was used as the control. Aliquots (0.5 mL) of both types of fat were transplanted into 10 nude mice and analyzed 10 weeks later. Western blotting, flow cytometry, and immunofluorescence were performed to assess the AER fat characteristics and underlying mechanisms. RESULTS: The retention rate of fat grafts in AER fat-treated animals was significantly higher than that in the Coleman group (mean [standard deviation] 54.6% [13%] vs 34.8% [9%]; P < 0.05) after 10 weeks. AER fat contained more dipeptidyl peptidase-4-expressing progenitor cells (3.3 [0.61] × 103 vs 2.0 [0.46] × 103 cells/mL; P < 0.05), adipose-derived plastic-adherent cells (6.0 [1.10] × 104 vs 2.6 [0.17] × 104 cells/mL; P < 0.001), and viable adipocytes than Coleman fat. Moreover, histologic analysis showed that AER fat grafts had better histologic structure and higher capillary density. CONCLUSIONS: AER fat transplantation is a potential strategy to improve the survival and long-term retention of fat grafts. AER fat contained more dipeptidyl peptidase-4-expressing progenitor cells.

Effects of physiological aging factor on bone tissue engineering repair based on fetal BMSCs.

BACKGROUND: At present, many laboratories and hospitals all over the world are attempting and exploring the clinical transformation of this tissue engineered bone graft (TEBG) strategy. Many successful cases of bone tissue engineering (BTE) repair were based on young individuals. But there are little studies about the effectiveness of TEBG strategy in physiological aged individuals. METHODS: In this research, we studied whether aging factor has influence on the skull repair effect of Fetal-TEBG, at the level of the large animal models. We used the fetal bone marrow stromal cells (Fetal-BMSCs) as the seed cells, combining the decalcified bone matrix (DBM) scaffolds, to repair the skull defects of the aged goats and the young goats. The repair effects on both aged goat and young goat were compared by Micro-CT and histology examination. RESULTS: The skull defects of the young goats could be repaired better than that of the aged goats after 6 months by Fetal-TEBG; In the aged goats, although not completely repaired, the defects repaired by Fetal-TEBG was better than that repaired by the Control DBM scaffold. CONCLUSIONS: Aging factor has impact on the bone repair effect of Fetal-TEBG; and the BTE strategy is still efficacious even in the aged individuals. The improvement of the aged state may promote the repair effect of the BTE in the aged individuals.

Study on the mechanism of Xinmailong injection against chronic heart failure based on transcriptomics and proteomics.

Xinmailong (XML), a traditional Chinese medicine derived from Periplaneta americana, is commonly used in China to treat chronic heart failure (CHF). However, its pharmacological mechanism remains unclear. In our research, we employed Doxorubicin (Dox) to create a CHF animal model and administered XML treatment to investigate the pharmacological effects of XML on CHF rats by combining transcriptomic and proteomic analyses. XML improved dox-induced CHF and improved cardiac function, and a joint multi-omics analysis demonstrated that it reduced cardiomyocyte fibrosis during CHF. There is further evidence that XML may alleviate cardiomyocyte fibrosis through its effects on the cGMP-PKG signaling pathway or by reducing the expression levels of COL1A1, COL3A1, MMP9, and CXCR2. In this study, the effects of XML on rats with CHF are examined at the transcriptional and protein levels, as well as its mechanism and mode of action in treating CHF. There may be novel therapeutic targets or clinical indications for XML-based CHF therapy resulting from the study's identification of significant differential genes and signaling pathways.

Metabonomic analysis of the anti-hepatic fibrosis effect of Ganlong capsules.

Context: Hepatic fibrosis is a progressive condition, often attributed to metabolic disorders, which may promote cirrhosis and liver cancer. Ganlong capsules derived from Periplaneta Americana have been shown to have a therapeutic effect on liver fibrosis but little is known about the molecular mechanisms involved. Objective: To investigate the metabolic modulations produced by Ganlong capsules in liver fibrosis. Methods: A carbon tetrachloride- (CCl4) treated rat model of liver fibrosis was constructed and Ganlong capsules administered. Levels of serum liver enzymes and pathological changes to the liver were evaluated. Non-targeted metabolomics of liver, serum and urine were used to investigate metabolic regulatory mechanisms. Results: Ganlong capsules reduced serum levels of liver enzymes and improved pathological changes in the rat model of fibrosis. Non-targeted metabolomics showed that Ganlong capsules ameliorated pathways of glycerophospholipid, linoleic acid, pyrimidine, glycine, butyric acid, valine, serine, threonine and arachidonic acid metabolism and biosynthesis of leucine and isoleucine. Such pathways influence the development of CCl4-induced liver fibrosis. Conclusion: Ganlong capsules had an anti-fibrotic hepatoprotective effect and regulated lipid, butyric acid, amino acid and arachidonic acid metabolism.

Corrigendum: Metabonomic analysis of the anti-hepatic fibrosis effect of Ganlong capsules.

[This corrects the article DOI: 10.3389/fphar.2023.1122118.].

Seroprevalence of Toxoplasma gondii antibodies from slaughter pigs in Chongqing, China.

Toxoplasmosis is a disease caused by the protozoan Toxoplasma gondii which infects most genera of warm-blooded animals, including humans. The objective of this investigation is to evaluate the seroprevalence of toxoplasmosis in pigs in Chongqing Municipality, southwest China. Slaughterhouse pigs' serum samples collected from six different regions in Chongqing were assayed for T. gondii antibodies by an indirect hemagglutination test. The average seroprevalence of T. gondii were found in 30.6% (278/908) in slaughter pigs, ranging from 21.6% to 40.9% among different sampling sites. The results indicated that toxoplasmosis in swine of Chongqing Municipality was relatively serious, and the pork may be an important source for human infection with T. gondii. Comprehensive measures are needed to strengthen further prevention and control of the disease in Chongqing.

Cell-free fat extract protects septic lethality via restraining NLRP3 inflammasome activation.

BACKGROUND: Sepsis is a dysregulated host response to infection with high mortality and current management cannot reach optimal remission. Previous studies have shown that cell-free fat extract (CEFFE) is a kind of bioactive extraction from adipose tissues and exhibits a potent anti-inflammatory effect on wound healing and inflammatory diseases. However, the potential role of CEFFE in sepsis remains unclear. METHODS: CEFFE was extracted from healthy donors and was intraperitoneally injected into septic mice. The septic mice models were constructed using lipopolysaccharide (LPS), E. coli, and cecal ligation and puncture (CLP). The survival of septic mice was detected for 96 h and Kaplan-Meier analysis was used to analyze the differences of survival rates. Lung tissues that were collected from septic mice were subjected to HE staining to evaluate the extent of lung injury, and the mice serum was obtained for inflammasome-related cytokines detection. Moreover, peritoneal macrophages were extracted from C57 mice and treated with CEFFE and/or inflammasome activators. The level of IL-1ß, IL-18, IL-6, and TNF-α was detected by ELISA, and the activation of NLRP3 were evaluated by Western Blot. Total mtDNA and mitochondrial permeability transition pore were determined to explore the mitochondrial dysfunction in the activation of NLRP3 inflammasome with or without CEFEE. Coimmunoprecipitation (Co-IP) assays were performed to confirm the mechanism of NLRP3 activation induced by CEFFE. RESULTS: CEFFE significantly improved the survival of sepsis mice and alleviate sepsis-induced lung injury. Moreover, CEFFE significantly decreased the level of inflammasome-cytokines (IL-1ß and IL-18) but not the pro-inflammatory cytokines such as IL-6 and TNF-α. Moreover, CEFFE markedly suppressed the canonical activation of NLRP3 inflammasome without affecting inflammasomes NLRC4 and AIM2. Additionally, the non-canonical activation of NLRP3 inflammasome was significantly inhibited by CEFFE. CEFFE treatment attenuated the mtDNA outflow and the increase of mitochondrial permeability induced by both canonical and non-canonical pathway of NLRP3 inflammasome activation. The results of Co-IP assays revealed that CEFFE remarkably attenuated the oligomerization of ASC and inhibited the association between NLRP3 and ASC. CONCLUSION: Our study revealed that CEFFE could significantly alleviate sepsis-related injuries possibly by suppressing NLRP3 inflammasome activation. CEFFE was a promising approach for sepsis treatment.

Advances in wound repair and regeneration: Systematic comparison of cell free fat extract and platelet rich plasma.

Background: Previous studies showed Cell free fat extract (CEFFE) and Platelet rich plasma (PRP) could effectively accelerate wound healing. However, the comparative study on curative effect is still lacking. A systematic comparison could provide more theoretical support and laboratory basis for the clinical application of CEFFE and PRP. Objective: To compare the efficacy of CEFFE and PRP in promoting skin wound repair. Methods: CEFFE and PRP were prepared according to the literature. The wound repair related factors were measured and compared. In vitro, the effects of both on cell migration, proliferation and tube formation were compared. In vivo, wound healing rate was measured on the 1st, 3rd, 9th, and 12th days after skin injury and treatment. Then the specimens were cut off for histological analysis. Results: Although the total protein content of PRP was significantly around 19 times higher than that of CEFFE, there was no statistical difference in the content of BDNF, EGF and VEGF between CEFFE and PRP. Even the NT-3 content of CEFFE was just slightly higher than that of PRP. The concentration of b-FGF, HGF and TGF-ß and PDGF-BB in PRP is higher than that in CEFFE, but there is only a very small difference between them. In vitro, PRP showed better efficacy than CEFFE in promoting fibroblast proliferation while there was no significant difference in promoting angiogenesis and fibroblast migration. Both PRP and CEFFE could significantly promote wound healing in mice. There was no statistical difference in wound healing between CEFFE and PRP groups in vivo. Immunohistochemical staining of Ki67&CD31 showed that there was no significant difference between PRP and CEFFE groups. Conclusion: The effect of PRP and CEFFE in promoting wound healing was similar. In clinical practice, the acquisition of PRP is relatively more convenient. Containing no cells, CEFFE has the advantage of easier preservation. For patients who have discarded adipose tissue, or contraindications to PRP technology, CEFFE technology may provide a new option for skin wound repair.

The ATP Level in the Medial Prefrontal Cortex Regulates Depressive-like Behavior via the Medial Prefrontal Cortex-Lateral Habenula Pathway.

BACKGROUND: Depression is the most common mental illness. Mounting evidence suggests that dysregulation of extracellular ATP (adenosine triphosphate) is involved in the pathophysiology of depression. However, the cellular and neural circuit mechanisms through which ATP modulates depressive-like behavior remain elusive. METHODS: By use of ex vivo slice electrophysiology, chemogenetic manipulations, RNA interference, gene knockout, behavioral testing, and two depression mouse models, one induced by chronic social defeat stress and one caused by a IP3R2-null mutation, we systematically investigated the cellular and neural circuit mechanisms underlying ATP deficiency-induced depressive-like behavior. RESULTS: Deficiency of extracellular ATP in both defeated susceptible mice and IP3R2-null mutation mice led to reduced GABAergic (gamma-aminobutyric acidergic) inhibition and elevated excitability in lateral habenula-projecting, but not dorsal raphe-projecting, medial prefrontal cortex (mPFC) neurons. Furthermore, the P2X2 receptor in GABAergic interneurons mediated ATP modulation of lateral habenula-projecting mPFC neurons and depressive-like behavior. Remarkably, chemogenetic activation of the mPFC-lateral habenula pathway induced depressive-like behavior in C57BL/6J mice, while inhibition of this pathway was sufficient to alleviate the behavioral impairment in both defeated susceptible and IP3R2-null mutant mice. CONCLUSIONS: Overall, our study provides compelling evidence that ATP level in the mPFC is critically involved in regulating depressive-like behavior in a pathway-specific manner. These results shed new light on the mechanisms underlying depression and the antidepressant effect of ATP.

The ATP Level in the mPFC Mediates the Antidepressant Effect of Calorie Restriction.

Food deprivation can rescue obesity and overweight-induced mood disorders, and promote mood performance in normal subjects. Animal studies and clinical research have revealed the antidepressant-like effect of calorie restriction, but little is known about the mechanism of calorie restriction-induced mood modification. Previous studies have found that astrocytes modulate depressive-like behaviors. Inositol 1,4,5-trisphosphate receptor type 2 (IP3R2) is the predominant isoform in mediating astrocyte Ca2+ signals and its genetic knockout mice are widely used to study astrocyte function in vivo. In this study, we showed that deletion of IP3R2 blocked the antidepressant-like effect induced by calorie restriction. In vivo microdialysis experiments demonstrated that calorie restriction induced an increase in ATP level in the medial prefrontal cortex (mPFC) in naïve mice but this effect disappeared in IP3R2-knockout mice, suggesting a role of astrocytic ATP in the calorie restriction-induced antidepressant effect. Further experiments showed that systemic administration and local infusion of ATP into the mPFC induced an antidepressant effect, whereas decreasing ATP by Apyrase in the mPFC blocked calorie restriction-induced antidepressant regulation. Together, these findings support a role for astrocytic ATP in the antidepressant-like effect caused by calorie restriction.

Impaired calcium signaling in astrocytes modulates autism spectrum disorder-like behaviors in mice.

Autism spectrum disorder (ASD) is a common neurodevelopmental disorder. The mechanisms underlying ASD are unclear. Astrocyte alterations are noted in ASD patients and animal models. However, whether astrocyte dysfunction is causal or consequential to ASD-like phenotypes in mice is unresolved. Type 2 inositol 1,4,5-trisphosphate 6 receptors (IP3R2)-mediated Ca2+ release from intracellular Ca2+ stores results in the activation of astrocytes. Mutations of the IP3R2 gene are associated with ASD. Here, we show that both IP3R2-null mutant mice and astrocyte-specific IP3R2 conditional knockout mice display ASD-like behaviors, such as atypical social interaction and repetitive behavior. Furthermore, we show that astrocyte-derived ATP modulates ASD-like behavior through the P2X2 receptors in the prefrontal cortex and possibly through GABAergic synaptic transmission. These findings identify astrocyte-derived ATP as a potential molecular player in the pathophysiology of ASD.

Involvement of P2X2 receptor in the medial prefrontal cortex in ATP modulation of the passive coping response to behavioral challenge.

P2X2 and P2X3 receptors are widely expressed in both the peripheral nervous system and the central nervous system and have been proven to participate in different peripheral sensory functions, but there are few studies on the involvement of P2X2 and P2X3 receptors in animal behaviors. Here we used P2X2 and P2X3 knockout mice to address this issue. P2X2 knockout mice showed normal motor function, exploratory behavior, anxiety-like behaviors, learning and memory behaviors and passive coping response to behavioral challenge. Nevertheless, the effect of ATP infusion in the medial prefrontal cortex (mPFC) on the passive coping response was blocked by P2X2 but not P2X3 receptor deletion. Additionally, no deficits in a wide variety of behavioral tests were observed in P2X3 knockout mice. These findings demonstrate a role of P2X2 receptor in the mPFC in adenosine-5'-triphosphate modulation of the passive coping response to behavioral challenge and show that the P2X2/P2X3 receptor is dispensable for behaviors.

Astrocytic GABAB Receptors in Mouse Hippocampus Control Responses to Behavioral Challenges through Astrocytic BDNF.

Major depressive disorder (MDD) is a common mood disorder that affects almost 20% of the global population. In addition, much evidence has implicated altered function of the gamma-aminobutyric acid (GABAergic) system in the pathophysiology of depression. Recent research has indicated that GABAB receptors (GABABRs) are an emerging therapeutic target in the treatment of stress-related disorders such as MDD. However, which cell types with GABABRs are involved in this process is unknown. As hippocampal dysfunction is implicated in MDD, we knocked down GABABRs in the hippocampus and found that knocking down these receptors in astrocytes, but not in GABAergic or pyramidal neurons, caused a decrease in immobility in the forced swimming test (FST) without affecting other anxiety- and depression-related behaviors. We also generated astrocyte-specific GABABR-knockout mice and found decreased immobility in the FST in these mice. Furthermore, the conditional knockout of GABABRs in astrocytes selectively increased the levels of brain-derived neurotrophic factor protein in hippocampal astrocytes, which controlled the decrease in immobility in the FST. Taken together, our findings contribute to the current understanding of which cell types expressing GABABRs modulate antidepressant activity in the FST, and they may provide new insights into the pathological mechanisms and potential targets for the treatment of depression.

Development of an Accurate and Proactive Immunomodulatory Strategy to Improve Bone Substitute Material-Mediated Osteogenesis and Angiogenesis.

Background: Treatment of large bone defects represents a major clinical problem worldwide. Suitable bone substitute materials are commonly required to achieve successful bone regeneration, and much effort has been spent to optimize their chemical compositions, 3D architecture and mechanical properties. However, material-immune system interactions are increasingly being recognized as a crucial factor influencing regeneration. Here, we envisioned an accurate and proactive immunomodulation strategy via delivery of IL-4 (key regulator of macrophage polarization) to promote bone substitute material-mediated regeneration. Methods: Four different IL-4 doses (0 ng, 10 ng, 50 ng and 100 ng) were delivered into rat large cranial bone defects at day 3 post-operation of decellularized bone matrix (DBM) material implantation, and the osteogenesis, angiogenesis and macrophage polarization were meticulously evaluated. Results: Micro-CT analysis showed that immunomodulation with 10 ng IL-4 significantly outperformed the other groups in terms of new bone formation (1.23-5.05 fold) and vascularization (1.29-6.08 fold), achieving successful defect bridging and good vascularization at 12 weeks. Histological analysis at 7 and 14 days showed that the 10 ng group generated the most preferable M1/M2 macrophage polarization profile, resulting in a pro-healing microenvironment with more IL-10 and less TNF-α secretion, a reduced apoptosis level in tissues around the materials, and enhanced mesenchymal stem cell migration and osteogenic differentiation. Moreover, in vitro studies revealed that M1 macrophages facilitated mesenchymal stem cell migration, while M2 macrophages significantly increased cell survival, proliferation and osteogenic differentiation, explaining the in vivo findings. Conclusions: Accurate immunomodulation via IL4 delivery significantly enhanced DBM-mediated osteogenesis and angiogenesis via the coordinated involvement of M1 and M2 macrophages, revealing the promise of this accurate and proactive immunomodulatory strategy for developing new bone substitute materials.