Ginsenoside Rb1 attenuates microglia activation to improve spinal cord injury via microRNA-130b-5p/TLR4/NF-κB axis

Brain plasticity and ginseng

Brain plasticity refers to the brain's ability to modify its structure, accompanied by its functional changes. It is influenced by learning, experiences, and dietary factors, even in later life. Accumulated researches have indicated that ginseng may protect the brain and enhance its function in pathological conditions. There is a compelling need for a more comprehensive understanding of ginseng's role in the physiological condition because many individuals without specific diseases seek to improve their health by incorporating ginseng into their routines. This review aims to deepen our understanding of how ginseng affects brain plasticity of people undergoing normal aging process. We provided a summary of studies that reported the impact of ginseng on brain plasticity and related factors in human clinical studies. Furthermore, we explored researches focused on the molecular mechanisms underpinning the influence of ginseng on brain plasticity and factors contributing to brain plasticity. Evidences indicate that ginseng has the potential to enhance brain plasticity in the context of normal aging by mediating both central and peripheral systems, thereby expecting to improve age-related declines in brain function. Moreover, given modern western diet can damage neuroplasticity in the long term, ginseng can be a beneficial supplement for better brain health.

Network pharmacology analysis and animal experiment validation of neuroinflammation inhibition by total ginsenoside in treating CSM

BACKGROUND

Cervical spondylotic myelopathy (CSM) is a degenerative pathology that affects both upper and lower extremity mobility and sensory function, causing significant pressure on patients and society. Prior research has suggested that ginsenosides may have neuroprotective properties in central nervous system diseases. However, the efficacy and mechanism of ginsenosides for CSM have yet to be investigated.

PURPOSE

This study aims to analyze the composition of ginsenosides using UPLC-MS, identify the underlying mechanism of ginsenosides in treating CSM using network pharmacology, and subsequently confirm the efficacy and mechanism of ginsenosides in rats with chronic spinal cord compression.

METHODS

UPLC-Q-TOF-MS was utilized to obtain mass spectrum data of ginsenoside samples. The chemical constituents of the samples were analyzed by consulting literature reports and relevant databases. Ginsenoside and CSM targets were obtained from the TCMSP, OMIM, and GeneCards databases. GO and KEGG analyses were conducted, and a visualization network of ginsenosides-compounds-key targets-pathways-CSM was constructed, along with molecular docking of key bioactive compounds and targets, to identify the signaling pathways and proteins associated with the therapeutic effects of ginsenosides on CSM. Chronic spinal cord compression rats were intraperitoneally injected with ginsenosides (50 mg/kg and 150 mg/kg) and methylprednisolone for 28 days, and motor function was assessed to investigate the therapeutic efficacy of ginsenosides for CSM. The expression of proteins associated with TNF, IL-17, TLR4/MyD88/NF-κB, and NLRP3 signaling pathways was assessed by immunofluorescence staining and western blotting.

RESULTS

Using UPLC-Q-TOF-MS, 37 compounds were identified from ginsenoside samples. Furthermore, ginsenosides-compounds-key targets-pathways-CSM visualization network indicated that ginsenosides may modulate the PI3K-Akt signaling pathway, TNF signaling pathway, MAPK signaling pathway, IL-17 signaling pathway, Toll-like receptor signaling pathway and Apoptosis by targeting AKT1, TNF, MAPK1, CASP3, IL6, and IL1B, exerting a therapeutic effect on CSM. By attenuating neuroinflammation through the TNF, IL-17, TLR4/MyD88/NF-κB, and MAPK signaling pathways, ginsenosides restored the motor function of rats with CSM, and ginsenosides 150 mg/kg showed better effect. This was achieved by reducing the phosphorylation of NF-κB and the activation of the NLRP3 inflammasome.

CONCLUSIONS

The results of network pharmacology indicate that ginsenosides can inhibit neuroinflammation resulting from spinal cord compression through multiple pathways and targets. This finding was validated through in vivo tests, which demonstrated that ginsenosides can reduce neuroinflammation by inhibiting NLRP3 inflammasomes via multiple signaling pathways, additionally, it should be noted that 150 mg/kg was a relatively superior dose. This study is the first to verify the intrinsic molecular mechanism of ginsenosides in treating CSM by combining pharmacokinetics, network pharmacology, and animal experiments. The findings can provide evidence for subsequent clinical research and drug development.

Downregulation of circAsxl2 Relieves Neuronal Injury Induced by oxygen-glucose deprivation/reperfusion

BACKGROUND

Circular RNAs (circRNAs) have been shown to play an important role in cerebral ischemia-reperfusion (I/R) injury. However, the role of circAsxl2 (mmu_circ_0000346) in cerebral I/R injury remains unclear.

METHODS

Mouse brain neuronal cell line (HT-22) was used to perform oxygen-glucose deprivation/reperfusion (OGD/R) treatment. The levels of circAsxl2, microRNA (miR)-130b-5p and forkhead box O3 (FOXO3) were determined using quantitative real-time PCR. Cell viability and apoptosis were measured using cell counting kit 8 assay and flow cytometry. Commercial kits were used to assess cell cytotoxicity, inflammation and oxidative stress. Protein expression was analyzed by western blot. RNA interaction was verified using dual-luciferase reporter assay, RIP assay and RNA pull-down assay.

RESULTS

CircAsxl2 was highly expressed in OGD/R-induced HT-22 cells, and its silencing could alleviate OGD/R-induced apoptosis, inflammation and oxidative stress in HT-22 cells. MiR-130b-5p was sponged by circAsxl2, and its inhibitor could overturn the regulation of circAsxl2 knockdown on OGD/R-induced neuronal injury. FOXO3 was targeted by miR-130b-5p and its expression was positively regulated by circAsxl2. In addition, the regulation of circAsxl2 knockdown on OGD/R-induced neuronal injury also was reversed by FOXO3 overexpression.

CONCLUSION

CircAsxl2/miR-130b-5p/FOXO3 axis accelerated OGD/R-induced neuronal injury, which might provide effective strategies for treating cerebral I/R injury.

Exosomes Derived from E2F1-/- Adipose-Derived Stem Cells Promote Skin Wound Healing via miR-130b-5p/TGFBR3 Axis

Background

Skin wound is a widespread health problem and brings extraordinary burdens to patients. Exosomes derived from adipose-derived stem cells (ADSC-Exos) are considered promising strategies for repairing skin wounds. E2F1 is a member of the E2F family of transcription factors involved in cell growth and apoptosis. E2F1 deficiency in mice enhances wound healing by improving collagen deposition and angiogenesis. Additionally, E2F1 can regulate the transcription and paracrine activity of multiple miRNAs, which will inevitably reshape the paracrine expression profile of ADSC-Exos. This study aimed to investigate the impact of transcription factor E2F1 deficiency on the functions of ADSC-Exos in promoting wound healing.

Methods

First, we obtained ADSCs from subcutaneous adipose tissues of WT and E2F1-/- C57BL/6 mice and separated their exosomes, denoted as ADSCWT-Exos and ADSCE2F1-/--Exos. The wound healing effects of ADSCWT-Exos and ADSCE2F1-/--Exos in full-thickness skin wound models were investigated by wound images, H&E staining, and immunohistochemical staining. For the in vitro study, the abilities of ADSCWT-Exos and ADSCE2F1-/--Exos to promote cell activities, collagen formation, and angiogenesis were evaluated. The potential mechanism by which ADSCE2F1-/--Exos promote wound healing was determined by miRNA sequencing, ChIP‒qPCR, and dual-luciferase assays.

Results

ADSCE2F1-/--Exos accelerated wound healing by promoting collagen formation and angiogenesis. As a result, compared with the lower wound healing rate of 30.5% within 7 days in the control group and 42.3% in the ADSCWT-Exo group, ADSCE2F1-/--Exos significantly increased the wound healing rate to 72.5%. In vitro, ADSCE2F1-/--Exos activated the function of fibroblasts and vascular endothelial cells. The loss of E2F1 promoted miR-130b-5p expression in ADSCE2F1-/--Exos through transcriptional regulation. MiRNA high-throughput sequencing identified 12 differently expressed miRNAs between ADSCE2F1-/- and ADSCWT. ADSCE2F1-/--Exos enhanced fibroblast activities via the miR-130b-5p/TGFBR3 axis and TGF-β activation.

Conclusion

Our results indicated that ADSCE2F1-/--Exos effectively promoted wound healing by regulating the miR-130b-5p/TGFBR3 axis, thus providing a novel strategy of gene-engineered stem cell exosomes for accelerating wound healing.

The impact of Yiwei decoction on the LncRNA and CircRNA regulatory networks in premature ovarian insufficiency

Premature ovarian insufficiency（POI）is a female reproductive aging illness. Yiwei decoction（YWD） is a traditional treatment for Yangming nourishment. YWD can treat premature ovarian insufficiency, but the exact molecular mechanism is unknown. As a result, the differential expression of Long noncoding RNAs (LncRNAs) and Circular RNAs(CircRNAs) in the ovary of POI rats after YWD treatment was investigated in this paper, and the CeRNA regulatory network was built. The model was created using cyclophosphamide. The model group + YWD was in Group A, the model control group was in Group B, and the regular control group was in Group C. In this study, 177 differential expression Long noncoding RNAs(DELncRNAs) and 190 differential expression Circular RNAs (DECircRNAs) were discovered between A and B (P＜0.05,|LogFC|＞1). Following the analysis, 27 DELncRNAs and 96 DECircRNAs (P-adjusted＜0.05,|LogFC|＞1) were discovered. At the same time, we built the CeRNA network using differentially expressed mRNAs and microRNAs (miRNAs) expression between groups A and B. The DELncRNAs were used to construct a lncRNA-miRNA-mRNA ceRNA network with 27 LncRNAs, 4 miRNAs, and 19 mRNAs. The DECircRNAs were utilized to establish a CircRNA-miRNA-mRNA ceRNA network that was made up of 15 CircRNAs, 4 miRNAs, and 20 mRNA. The highly correlated regulatory networks were the LncMSTRG.22691.3/miR-3102/ANGPT4 and Circ10_34698898_34699378/miR-33-5p/TTC22. Circ20_12035276_12036793、Circ20_30693935_30696337、Circ4_157723097_157723378 and Circ4_157923266_157923904 occurred concurrently in AvsB, BvsC, and AvsC. MiRDB predicted eight target miRNAs for these CircRNAs. The miRanda(score = 140，energy = -1) binding energy calculation revealed that seven miRNAs were well combined with three CircRNA base complementary pairs. This implies that 3 DECircRNAs could serve as spongy bodies for these miRNAs. Network pharmacological analysis showed that ten active components in YWD may regulate the expression of LncRNAs and CircRNAs, such as Stigmasterol, Uridine, Ophiopogonanone A, Gamma-Aminobutyric Acid, and others. In conclusion, this study combined transcriptomics and network pharmacological analysis to identify differentially expressed lncRNAs as well as CircRNAs in ovaries of YWD-treated POI rats, thereby constructing ceRNA networks implicated in POI. This would contribute to clarifying the pathways by which Chinese herbal compounds regulate gene expression in POI.

Identification and Validation of Ferroptosis-Related Genes in Patients with Acute Spinal Cord Injury

Ferroptosis plays crucial roles in the pathology of spinal cord injury (SCI). The purpose of this study was to identify differentially expressed ferroptosis-related genes (DE-FRGs) in human acute SCI by bioinformatics analysis and validate the hub DE-FRGs in non-SCI and SCI patients. The GSE151371 dataset was downloaded from the Gene Expression Omnibus and difference analysis was performed. The differentially expressed genes (DEGs) in GSE151371 overlapped with the ferroptosis-related genes (FRGs) obtained from the Ferroptosis Database. A total of 41 DE-FRGs were detected in 38 SCI samples and 10 healthy samples in GSE151371. Then, enrichment analyses of these DE-FRGs were performed for functional annotation. The GO enrichment results showed that upregulated DE-FRGs were mainly associated with reactive oxygen species and redox reactions, and the KEGG enrichment analysis indicated involvement in some diseases and ferroptosis pathways. Protein-protein interaction (PPI) analysis and lncRNA-miRNA-mRNA regulatory network were performed to explore the correlations between genes and regulatory mechanisms. The relationship between DE-FRGs and differentially expressed mitochondria-related genes (DE-MRGs) was also analyzed. Finally, quantitative real-time polymerase chain reaction (qRT-PCR) was used to verify the hub DE-FRGs in clinical blood samples from acute SCI patients and healthy controls. Consistent with the bioinformatics results, qRT-PCR of the clinical samples indicated similar expression levels of TLR4, STAT3, and HMOX1. This study identified DE-FRGs in blood samples from SCI patients, and the results could improve our understanding of the molecular mechanisms of ferroptosis in SCI. These candidate genes and pathways could be therapeutic targets for SCI.

Relationship between the therapeutic potential of various plant-derived bioactive compounds and their related microRNAs in neurological disorders

BACKGROUND

Neurological disorders, such as ischemic stroke, spinal cord injury, neurodegenerative diseases, and glioblastoma often lead to long-term disability and death. MicroRNAs (miRNAs) are small single-stranded non-coding RNAs of approximately 22 nucleotides, known to participate in both normal and pathological development, making them ideal therapeutic targets for clinical intervention. Several recent studies have suggested that plant-derived bioactive compounds (PDBCs) can have anti-atherosclerosis, antioxidant, and anti-inflammatory effects by regulating miRNAs. Thus, miRNAs are novel targets for the action of PDBCs.

PURPOSE

The aim of this review was to evaluate the current status of PDBCs targeted miRNAs by dissecting their development status through a literature review.

METHODS

A manual and electronic search was performed for English articles available from inception up to June 2022 reporting PDBCs and their regulating relationship with miRNAs for the therapeutic potential of neurological disorders. Information was retrieved from scientific databases including PubMed, ScienceDirect, Web of Science, Google Scholar and Chemical Abstracts Services. Keywords used for the search engines were "miRNAs" AND "Plant-derived bioactive compounds" in conjunction with "(native weeds OR alien invasive)" AND "traditional herbal medicine".

RESULTS

A total of 37 articles were retrieved on PDBCs and their related miRNAs in neurological disorders. These PDBCs from traditional herbal medicine may play a therapeutic role in neurological disorders in a variety of mechanisms by regulating the corresponding miRNAs. These mechanisms mainly include inhibiting oxidative stress, anti-neuroinflammation, anti-autophagy, and anti-apoptosis. PDBC are a group of chemically distinct compounds derived from medicinal plants, some of which have therapeutic effects on neurological disorders.

CONCLUSION

The emergence of miRNAs as pathological regulatory factors provides a new direction for the study of bioactive compounds in Traditional Chinese medicine and the elucidating of their epigenetic effects. Elucidating the regulatory relationship between bioactive compounds and miRNAs may help to identify new therapeutic targets and promoting the application of these compounds in precision medicine through their targeted molecular activity.

Plasma Extracellular Vesicles Play a Role in Immune System Modulation in Minimal Hepatic Encephalopathy

Minimal hepatic encephalopathy (MHE) is associated with changes in the immune system including an increased pro-inflammatory environment and altered differentiation of CD4+ T lymphocytes. The mechanisms remain unknown. Changes in extracellular vesicle (EV) cargo including proteins and miRNAs could play a main role as mediators of immune system changes associated with MHE. The aim was to assess whether plasma EVs from MHE patients played a role in inducing the pro-inflammatory environment and altered differentiation of CD4+ T lymphocyte subtypes in MHE patients. We characterized the miRNA and protein cargo of plasma EVs from 50 cirrhotic patients (27 without and 23 with MHE) and 24 controls. CD4+ T cells from the controls were cultured with plasma EVs from the three groups of study, and the cytokine release and differentiation to CD4+ T-cell subtypes were assessed. Plasma EVs from MHE patients had altered miRNA and protein contents, and were enriched in inflammatory factors compared to the controls and patients without MHE. EVs from MHE patients modulated the expression of pro-inflammatory IL-17, IL-21, and TNF-α and anti-inflammatory TGF-β in cultured CD4+ T lymphocytes, and increased the proportion of Th follicular and Treg cells and the activation of Th17 cells. In conclusion, plasma EVs could play an important role in the induction of immune changes observed in MHE.

Mechanisms of ginsenosides exert neuroprotective effects on spinal cord injury: A promising traditional Chinese medicine

Spinal cord injury (SCI) is a devastating disorder of the central nervous system (CNS). It is mainly caused by trauma and reduces the quality of life of the affected individual. Ginsenosides are safe and effective traditional Chinese medicines (TCMs), and their efficacy against SCI is being increasingly researched in many countries, especially in China and Korea. This systematic review evaluated the neuroprotective effects of ginsenosides in SCI and elucidated their properties.

The Anti-inflammation Property of Olfactory Ensheathing Cells in Neural Regeneration After Spinal Cord Injury

Neural regeneration has troubled investigators worldwide in the past decades. Currently, cell transplantation emerged as a breakthrough targeted therapy for spinal cord injury (SCI) in the neurotrauma field, which provides a promising strategy in neural regeneration. Olfactory ensheathing cells (OECs), a specialized type of glial cells, is considered as the excellent candidate due to its unique variable and intrinsic regeneration-supportive properties. In fact, OECs could support olfactory receptor neuron turnover and axonal extension, which is essential to maintain the function of olfactory nervous system. Hitherto, an increasing number of literatures demonstrate that transplantation of OECs exerts vital roles in neural regeneration and functional recovery after neural injury, including central and peripheral nervous system. It is common knowledge that the deteriorating microenvironment (ischemia, hypoxia, scar, acute and chronic inflammation, etc.) resulting from injured nervous system is adverse for neural regeneration. Interestingly, recent studies indicated that OECs could promote neural repair through improvement of the disastrous microenvironments, especially to the overwhelmed inflammatory responses. Although OECs possess unusual advantages over other cells for neural repair, particularly in SCI, the mechanisms of OEC-mediated neural repair are still controversial with regard to anti-inflammation. Therefore, it is significant to summarize the anti-inflammation property of OECs, which is helpful to understand the biological characteristics of OECs and drive future studies. Here, we mainly focus on the anti-inflammatory role of OECs to make systematic review and discuss OEC-based therapy for CNS injury.

Neuroprotective Mechanisms of Ginsenoside Rb1 in Central Nervous System Diseases

Panax ginseng and Panax notoginseng, two well-known herbs with enormous medical value in Asian countries, have a long usage history in China for the therapy of some diseases, such as stroke. Ginsenoside Rb1 is one of most important active ingredients in Panax ginseng and Panax notoginseng. In the last two decades, more attention has focused on ginsenoside Rb1 as an antioxidative, anti-apoptotic and anti-inflammatory agent that can protect the nervous system. In the review, we summarize the neuroprotective roles of ginsenoside Rb1 and its potential mechanisms in central nervous system diseases (CNSDs), including neurodegenerative diseases, cerebral ischemia injury, depression and spinal cord injury. In conclusion, ginsenoside Rb1 has a potential neuroprotection due to its inhibition of oxidative stress, apoptosis, neuroinflammation and autophagy in CNSDs and may be a promising candidate agent for clinical therapy of CNSDs in the future.

Microglia in depression: an overview of microglia in the pathogenesis and treatment of depression

Major depressive disorder is a highly debilitating psychiatric disorder involving the dysfunction of different cell types in the brain. Microglia are the predominant resident immune cells in the brain and exhibit a critical role in depression. Recent studies have suggested that depression can be regarded as a microglial disease. Microglia regulate inflammation, synaptic plasticity, and the formation of neural networks, all of which affect depression. In this review, we highlighted the role of microglia in the pathology of depression. First, we described microglial activation in animal models and clinically depressed patients. Second, we emphasized the possible mechanisms by which microglia recognize depression-associated stress and regulate conditions. Third, we described how antidepressants (clinical medicines and natural products) affect microglial activation. Thus, this review aimed to objectively analyze the role of microglia in depression and focus on potential antidepressants. These data suggested that regulation of microglial actions might be a novel therapeutic strategy to counteract the adverse effects of devastating mental disorders.

Strategies for Biomaterial-Based Spinal Cord Injury Repair via the TLR4-NF-κB Signaling Pathway

The repair and motor functional recovery after spinal cord injury (SCI) has remained a clinical challenge. Injury-induced gliosis and inflammation lead to a physical barrier and an extremely inhibitory microenvironment, which in turn hinders the recovery of SCI. TLR4-NF-κB is a classic implant-related innate immunomodulation signaling pathway and part of numerous biomaterial-based treatment strategies for SCI. Numerous experimental studies have demonstrated that the regulation of TLR4-NF-κB signaling pathway plays an important role in the alleviation of inflammatory responses, the modulation of autophagy, apoptosis and ferroptosis, and the enhancement of anti-oxidative effect post-SCI. An increasing number of novel biomaterials have been fabricated as scaffolds and carriers, loaded with phytochemicals and drugs, to inhibit the progression of SCI through regulation of TLR4-NF-κB. This review summarizes the empirical strategies for the recovery after SCI through individual or composite biomaterials that mediate the TLR4-NF-κB signaling pathway.

Comprehensive Analysis of the Effect of 20(R)-Ginsenoside Rg3 on Stroke Recovery in Rats via the Integrative miRNA–mRNA Regulatory Network

MicroRNAs (miRNAs) are a class of small, endogenous, noncoding RNAs. Recent research has proven that miRNAs play an essential role in the occurrence and development of ischemic stroke. Our previous studies confirmed that 20(R)-ginsenosideRg3 [20(R)-Rg3] exerts beneficial effects on cerebral ischemia–reperfusion injury (CIRI), but its molecular mechanism has not been elucidated. In this study, we used high-throughput sequencing to investigate the differentially expressed miRNA and mRNA expression profiles of 20(R)-Rg3 preconditioning to ameliorate CIRI injury in rats and to reveal its potential neuroprotective molecular mechanism. The results show that 20(R)-Rg3 alleviated neurobehavioral dysfunction in MCAO/R-treated rats. Among these mRNAs, 953 mRNAs were significantly upregulated and 2602 mRNAs were downregulated in the model group versus the sham group, whereas 437 mRNAs were significantly upregulated and 35 mRNAs were downregulated in the 20(R)-Rg3 group in contrast with those in the model group. Meanwhile, the expression profile of the miRNAs showed that a total of 283 differentially expressed miRNAs were identified, of which 142 miRNAs were significantly upregulated and 141 miRNAs were downregulated in the model group compared with the sham group, whereas 34 miRNAs were differentially expressed in the 20(R)-Rg3 treatment group compared with the model group, with 28 miRNAs being significantly upregulated and six miRNAs being significantly downregulated. Furthermore, 415 (391 upregulated and 24 downregulated) differentially expressed mRNAs and 22 (17 upregulated and 5 downregulated) differentially expressed miRNAs were identified to be related to 20(R)-Rg3′s neuroprotective effect on stroke recovery. The Kyoto Encyclopedia of Genes and Genomes (KEGG) results showed that 20(R)-Rg3 could modulate multiple signaling pathways related to these differential miRNAs, such as the cGMP-PKG, cAMP and MAPK signaling pathways. This study provides new insights into the protective mechanism of 20(R)-Rg3 against CIRI, and the mechanism may be partly associated with the regulation of brain miRNA expression and its target signaling pathways.

Ingredients with anti-inflammatory effect from medicine food homology plants

Inflammation occurs when the immune system responses to external harmful stimuli and infection. Chronic inflammation induces various diseases. A variety of foods are prescribed in the traditional medicines of many countries all over the world, which gave birth to the concept of medicine food homology. Over the past few decades, a number of secondary metabolites from medicine food homology plants have been demonstrated to have anti-inflammatory effects. In the present review, the effects and mechanisms of the medicine food homology plants-derived active components on relieving inflammation and inflammation-mediated diseases were summarized and discussed. The information provided in this review is valuable to future studies on anti-inflammatory ingredients derived from medicine food homology plants as drugs or food supplements.

Protective Effect of Ginsenoside Rb1 Nanoparticles Against Contrast-Induced Nephropathy by Inhibiting High Mobility Group Box 1 Gene/Toll-Like Receptor 4/NF-κB Signaling Pathway

With the progress made in the widespread application of interventional radiology procedures, there has been an increasing number of patients who suffer from cardiovascular diseases and go through imaging and interventional treatment with iodine contrast medium (ICM) year by year. In turn, there has been an increasing amount of concern over acute kidney injury (AKI) brought about by ICM. As evidenced by numerous studies, the initiation of inflammatory response plays a critical role in the development of ICM-induced AKI. Correspondingly, the strategy of targeting renal inflammatory response and cytokine release could provide an effective solution to mitigating the ICM-induced AKI. Moreover, Ginsenoside Rb1 (GRb1) constitutes one of the major active components of ginseng and features a wide range of vital biological functions. Judging from the research findings, GRb1 could impose antioxidant and anti-inflammatory effects on cardiovascular diseases, in addition to lung, liver and kidney diseases. However, reports on whether GRb1 could impose a protective effect against contrast-induced nephropathy (CIN) are absent. In this study, we have examined the therapeutic effects imposed by GRb1 as well as the potential molecular mechanism by establishing an in vivo and in vitro model of CIN. In addition, we have set up a mouse model of CIN through sequential intravenous injection of indomethacin, N(ω)-nitro-Larginine methyl ester (L-NAME), and iopromide. To further enhance the bioavailability of GRb1, we have encapsulated GRb1 with polyethylene glycol (PEG)/poly lactic-co-glycolic acid (PLGA) nanocarriers to generate GRb1 nanoparticles (NPs) conducting the in vivo experiments. During the in vitro experiments, we have adopted GRb1 to treat NRK-52E cells or cells transfected with the high mobility group box 1 gene (HMGB1) overexpression plasmid. As shown by the in vivo experimental results, GRb1 NPs could evidently improve the renal dysfunction in CIN, diminish the extent of apoptosis of tubular epithelial cells, and reduce the expression of high mobility group box 1 (HMGB1) and cytokines (tumor necrosis factor (TNF-α), interleukin (IL) 6 and IL-1β). In addition, GRb1 NPs are found to be capable of preventing the activation of Toll-like receptor 4 (TLR4)/NF-κB signaling pathway triggered by contrast medium. The in vitro experimental results have exactly confirmed the findings of the in vivo experiments. In the meantime, through the observation of the in vitro assays, overexpression of HMGB1 can partially counteract the beneficial effects imposed by GRb1. Judging from our research data, GRb1 could impose a protective effect against CIN by inhibiting inflammatory response via HMGB1/TLR4/NF-κB pathway, whereas HMGB1 constitutes a critical molecular target of GRb1.

Ginsenoside Rb1 induces a pro-neurogenic microglial phenotype via PPARγ activation in male mice exposed to chronic mild stress

Background

Anti-inflammatory approaches are emerging as a new strategy for the treatment of depressive disorders. Ginsenoside Rb1 (GRb1), a major component of Panax ginseng, can inhibit inflammatory cascade and alleviate depressive-like behaviors. Microglia can promote or inhibit adult hippocampal neurogenesis according to their functional phenotypes. Here, we examine whether GRb1 may exert antidepressant effects by promoting a pro-neurogenic phenotype of microglia and thereby increasing neurogenesis.

Methods

The antidepressant effects of GRb1 or the licensed antidepressant imipramine (IMI) were assessed in chronic mild stress (CMS)-exposed male mice. The depressive-like behaviors of mice were evaluated by sucrose preference test, forced swimming test (FST), and tail suspension test (TST). The microglial phenotypes were identified by pro- and anti-inflammatory cytokine expression and morphological properties, analyzed by RT-qPCR, western blotting, and immunofluorescence staining. The effect of GRb1-treated microglia on adult hippocampal neurogenesis in vivo and in vitro was detected using immunofluorescence staining.

Results

Behavioral assessment indicated that GRb1 or IMI treatment alleviated depressive-like behaviors in CMS-exposed mice. Immunofluorescence examination demonstrated that GRb1 induced a pro-neurogenic phenotype of microglia via activating PPARγ in vivo and in vitro, which were effectively reversed by the PPARγ inhibitor GW9662. In addition, GRb1-treated microglia increased the proliferation and differentiation of neural precursor cells.

Conclusions

These findings demonstrated that GRb1 alleviated depressive-like behaviors of CMS-exposed male mice mainly through PPARγ-mediated microglial activation and improvement of adult hippocampus neurogenesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-021-02185-0.

miRNA-130b-5p promotes hepatic stellate cell activation and the development of liver fibrosis by suppressing SIRT4 expression

Liver fibrosis is a progressive disease accompanied by the deposition of extracellular matrix (ECM). Numerous reports have demonstrated that alterations in the expression of microRNAs (miRNAs) are related to liver disease. However, the effect of individual miRNAs on liver fibrosis has not been studied. Hepatic stellate cells (HSCs), being responsible for producing ECM, exert an important influence on liver fibrosis. Then, microarray analysis of non‐activated and activated HSCs induced by transforming growth factor β1 (TGF‐β1) showed that miR‐130b‐5p expression was strongly up‐regulated during HSC activation. Moreover, the progression of liver fibrosis had a close connection with the expression of miR‐130b‐5p in different liver fibrosis mouse models. Then, we identified that there were specific binding sites between miR‐130b‐5p and the 3′ UTR of Sirtuin 4 (SIRT4) via a luciferase reporter assay. Knockdown of miR‐130b‐5p increased SIRT4 expression and ameliorated liver fibrosis in mice transfected with antagomiR‐130b‐5p oligos. In general, our results suggested that miR‐130b‐5p promoted HSC activation by targeting SIRT4, which participates in the AMPK/TGF‐β/Smad2/3 signalling pathway. Hence, regulating miR‐130b‐5p maybe serve as a crucial therapeutic treatment for hepatic fibrosis.

Catalpol Protects Against Spinal Cord Injury in Mice Through Regulating MicroRNA-142-Mediated HMGB1/TLR4/NF-κB Signaling Pathway

Background: Spinal cord injury (SCI) is a devastating condition that leads to paralysis, disability and even death in severe cases. Inflammation, apoptosis and oxidative stress in neurons are key pathogenic processes in SCI. Catalpol (CTP), an iridoid glycoside extracted from Rehmannia glutinosa, has many pharmacological activities, such as anti-inflammatory, anti-oxidative and anti-apoptotic properties.

Purpose: Here, we investigated whether CTP could exert neuroprotective effects against SCI, and explored the underlying mechanism involved.

Methods: SCI was induced by a weight-drop device and treated with CTP (10 mg and 60 mg/kg). Then the locomotor function of SCI mice was evaluated by the BBB scores, spinal cord edema was measured by the wet/dry weight method, oxidative stress markers and inflammatory factors were detected by commercial kits and neuronal death was measured by TUNEL staining. Moreover, the microRNA expression profile in spinal cords from mice following SCI was analyzed using miRNA microarray. In addition, reactive oxygen species (ROS) generation, inflammatory response and cell apoptosis were detected in murine microglia BV2 cells under oxygen-glucose deprivation (OGD) and CTPtreatment.

Results: Our data showed that CTP treatment could improve the functional recovery, as well as suppress the apoptosis, alleviate inflammatory and oxidative response in SCI mice. In addition, CTP was found to be up-regulated miR-142 and the protective effects of CTP on apoptosis, inflammatory and oxidative response may relate to its regulation of HMGB1/TLR4/NF-κB pathway through miR-142.

Conclusion: Our findings suggest that CTP may protect the spinal cord from SCI by suppression of apoptosis, oxidative stress and inflammatory response via miR-142/HMGB1/TLR4/NF-κB pathway.

Long noncoding RNA XIST knockdown relieves the injury of microglia cells after spinal cord injury by sponging miR-219-5p

Long noncoding RNAs have been demonstrated to play crucial roles in the pathogenesis of spinal cord injury (SCI). In this study, we aimed to explore the roles and underlying mechanisms of lncRNA X-inactive specific transcript (XIST) in SCI progression. SCI mice model was constructed and evaluated by the Basso-Beattie-Bresnahan method. The SCI cell model was constructed by treating BV2 cells with lipopolysaccharide (LPS). The levels of XIST and miR-219-5p were determined by the reverse transcription quantitative polymerase chain reaction. The concentrations of inflammatory cytokines were measured by enzyme-linked immunosorbent assay. Protein levels were measured via western blot assay. Cell viability and apoptosis were evaluated by cell counting kit-8 assay and flow cytometry analysis, respectively. The relationship between XIST and miR-219-5p was analyzed by online tool starBase, dual-luciferase reporter assay, and RNA immunoprecipitation assay. As a result, the XIST level was enhanced and the miR-219-5p level was declined in the SCI mice model. XIST was also upregulated in LPS-induced BV2 cells. LPS treatment restrained BV2 cell viability and accelerated apoptosis and inflammatory response. XIST knockdown effectively weakened LPS-induced BV2 cell injury. miR-219-5p was identified as a target of XIST. Moreover, inhibition of miR-219-5p restored the impacts of XIST knockdown on cell viability, apoptosis, and inflammation in LPS-treated BV2 cells. In addition, LPS-induced XIST promoted the activation of the nuclear factor-κB (NF-κB) pathway by sponging miR-219-5p. In conclusion, XIST silencing promoted microglial cell viability and repressed apoptosis and inflammation by sponging miR-219-5p, thus promoting the recovery of SCI.

Ninjurin-1: a biomarker for reflecting the process of neuroinflammation after spinal cord injury

Previous studies have shown that Ninjurin-1 participates in cell trafficking and axonal growth following central and peripheral nervous system neuroinflammation. But its precise roles in these processes and involvement in spinal cord injury pathophysiology remain unclear. Western blot assay revealed that Ninjurin-1 levels in rats with spinal cord injury exhibited an upregulation until day 4 post-injury and slightly decreased thereafter compared with sham controls. Immunohistochemistry analysis revealed that Ninjurin-1 immunoreactivity in rats with spinal cord injury sharply increased on days 1 and 4 post-injury and slightly decreased on days 7 and 21 post-injury compared with sham controls. Ninjurin-1 immunostaining was weak in vascular endothelial cells, ependymal cells, and some glial cells in sham controls while it was relatively strong in macrophages, microglia, and reactive astrocytes. These findings suggest that a variety of cells, including vascular endothelial cells, macrophages, and microglia, secrete Ninjurin-1 and they participate in the pathophysiology of compression-induced spinal cord injury. All experimental procedures were approved by the Care and Use of Laboratory Animals of Jeju National University (approval No. 2018-0029) on July 6, 2018.