Promoting therapeutic angiogenesis of focal cerebral ischemia using thrombospondin-4 (TSP4) gene-modified bone marrow stromal cells (BMSCs) in a rat model

Nervonic Acid Inhibits Replicative Senescence of Human Wharton's Jelly-Derived Mesenchymal Stem Cells

Cellular senescence causes cell cycle arrest and promotes permanent cessation of proliferation. Since the senescence of mesenchymal stem cells (MSCs) reduces proliferation and multipotency and increases immunogenicity, aged MSCs are not suitable for cell therapy. Therefore, it is important to inhibit cellular senescence in MSCs. It has recently been reported that metabolites can control aging diseases. Therefore, we aimed to identify novel metabolites that regulate the replicative senescence in MSCs. Using a fecal metabolites library, we identified nervonic acid (NA) as a candidate metabolite for replicative senescence regulation. In replicative senescent MSCs, NA reduced senescence-associated β-galactosidase positive cells, the expression of senescence-related genes, as well as increased stemness and adipogenesis. Moreover, in non-senescent MSCs, NA treatment delayed senescence caused by sequential subculture and promoted proliferation. We confirmed, for the first time, that NA delayed and inhibited cellular senescence. Considering optimal concentration, duration, and timing of drug treatment, NA is a novel potential metabolite that can be used in the development of technologies that regulate cellular senescence.

Angiogenesis after ischemic stroke

Owing to its high disability and mortality rates, stroke has been the second leading cause of death worldwide. Since the pathological mechanisms of stroke are not fully understood, there are few clinical treatment strategies available with an exception of tissue plasminogen activator (tPA), the only FDA-approved drug for the treatment of ischemic stroke. Angiogenesis is an important protective mechanism that promotes neural regeneration and functional recovery during the pathophysiological process of stroke. Thus, inducing angiogenesis in the peri-infarct area could effectively improve hemodynamics, and promote vascular remodeling and recovery of neurovascular function after ischemic stroke. In this review, we summarize the cellular and molecular mechanisms affecting angiogenesis after cerebral ischemia registered in PubMed, and provide pro-angiogenic strategies for exploring the treatment of ischemic stroke, including endothelial progenitor cells, mesenchymal stem cells, growth factors, cytokines, non-coding RNAs, etc.

Manf Enhances the Pyroptosis Inhibition of Bone Marrow-derived Mesenchymal Stem Cells to Relieve Cerebral Infarction Injury

Cerebral infarction is a common disease characterized by high mortality, a narrow therapeutic window, and limited therapeutic options. Recently, cell therapy based on gene modification has brought a glimmer of hope to the treatment of cerebral infarction although the explicit underlying mechanism is beyond being well dissected. In the present study, we constructed an animal model of middle cerebral artery occlusion (MCAO), compared differentially expressed genes (DEGs) between the sham and MCAO groups by single-cell RNA sequencing (scRNA-seq) to explore the potential cell death-related pathways involved in cerebral infarction, and transfected Manf into BMSCs by lentivirus. Subsequently, we injected BMSCs (bone marrow-derived mesenchymal stem cells), Manf-modified BMSCs, or lentivirus encoding Manf into the brain. Their effects on MANF content, apoptosis, pyroptosis, infarct volume in the brain, and neurological function were evaluated after MCAO. We found that the DEGs upregulated in four major cell clusters after MCAO and were enriched with not only apoptosis, ferroptosis, and necroptosis but also with pyroptosis-related pathways. In addition, transfection of Manf into BMSCs significantly increased the expression and secretion of MANF in BMSCs; BMSCs, Manf-modified BMSCs, and Manf treatment all resulted in an increase in Manf content in the brain, a decrease in the expression of apoptosis- and pyroptosis-related molecules, a reduction in infarct volume, and an improvement in neurological function after MCAO. Moreover, Manf-modified BMSCs have the strongest therapeutic effect. Collectively, Manf-modified BMSCs ameliorate ischemic injury after cerebral infarction by repressing apoptosis- and pyroptosis-related molecules, which represents a new cell therapy strategy for cerebral infarction.

Experimental treatments to attenuate blood spinal cord barrier rupture in rats with traumatic spinal cord injury: A meta-analysis and systematic review

Background: Traumatic spinal cord injury (t-SCI) is a severe injury that has a devastating impact on neurological function. Blood spinal cord barrier (BSCB) destruction following SCI aggravates the primary injury, resulting in a secondary injury. A series of experimental treatments have been proven to alleviate BSCB destruction after t-SCI.

Methods: From a screen of 1,189 papers, which were retrieved from Pubmed, Embase, and Web of science, we identified 28 papers which adhered to strict inclusion and exclusion criteria. Evans blue (EB) leakage on the first day post-SCI was selected as the primary result. Secondary outcomes included the expression of tight junction (TJ) proteins and adhesion junction (AJ) proteins in protein immunoblotting. In addition, we measured functional recovery using the Basso, Beattie, Besnahan (BBB) score and we analyzed the relevant mechanisms to explore the similarities between different studies.

Result: The forest plot of Evans blue leakage (EB leakage) reduction rate: the pooled effect size of the 28 studies was 0.54, 95% CI: 0.47–0.61, p < 0.01. This indicates that measures to mitigate BSCB damage significantly improved in reducing overall EB leakage. In addition TJ proteins (Occludin, Claudin-5, and ZO-1), AJ proteins (P120 and β-catenin) were significantly upregulated after treatment in all publications. Moreover, BBB scores were significantly improved. Comprehensive studies have shown that in t-SCI, inhibition of matrix metalloproteinases (MMPs) is the most commonly used mechanism to mitigate BSCB damage, followed by endoplasmic reticulum (ER) stress and the Akt pathway. In addition, we found that bone marrow mesenchymal stem cell-derived exosomes (BMSC-Exos), which inhibit the TIMP2/MMP signaling pathway, may be the most effective way to alleviate BSCB injury.

Conclusion: This study systematically analyzes the experimental treatments and their mechanisms for reducing BSCB injury in the early stage of t-SCI. BMSC-Exos, which inhibit MMP expression, are currently the most effective therapeutic modality for alleviating BSCB damage. In addition, the regulation of MMPs in particular as well as the Akt pathway and the ER stress pathway play important roles in alleviating BSCB injury.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022324794.

Effect of Neurorepair for Motor Functional Recovery Enhanced by Total Saponins From Trillium tschonoskii Maxim. Treatment in a Rat Model of Focal Ischemia

Trillium tschonoskii Maxim. (TTM), is a perennial herb from Liliaceae, that has been widely used as a traditional Chinese medicine treating cephalgia and traumatic hemorrhage. The present work was designed to investigate whether the total saponins from Trillium tschonoskii Maxim. (TSTT) would promote brain remodeling and improve gait impairment in the chronic phase of ischemic stroke. A focal ischemic model of male Sprague-Dawley (SD) rats was established by permanent middle cerebral artery occlusion (MCAO). Six hours later, rats were intragastrically treated with TSTT (120, 60, and 30 mg/kg) and once daily up to day 30. The gait changes were assessed by the CatWalk-automated gait analysis system. The brain tissues injuries, cerebral perfusion and changes of axonal microstructures were detected by multimodal magnetic resonance imaging (MRI), followed by histological examinations. The axonal regeneration related signaling pathways including phosphatidylinositol 3-kinases (PI3K)/protein kinase B (AKT)/glycogen synthase kinase-3 (GSK-3)/collapsin response mediator protein-2 (CRMP-2) were measured by western blotting. TSTT treatment significantly improved gait impairment of rats. MRI analysis revealed that TSTT alleviated tissues injuries, significantly improved cerebral blood flow (CBF), enhanced microstructural integrity of axon and myelin sheath in the ipsilesional sensorimotor cortex and internal capsule. In parallel to MRI findings, TSTT preserved myelinated axons and promoted oligodendrogenesis. Specifically, TSTT interventions markedly up-regulated expression of phosphorylated GSK-3, accompanied by increased expression of phosphorylated PI3K, AKT, but reduced phosphorylated CRMP-2 expression. Taken together, our results suggested that TSTT facilitated brain remodeling. This correlated with improving CBF, encouraging reorganization of axonal microstructure, promoting oligodendrogenesis and activating PI3K/AKT/GSK-3/CRMP-2 signaling, thereby improving poststroke gait impairments.

Trillium tschonoskii rhizomes' saponins induces oligodendrogenesis and axonal reorganization for ischemic stroke recovery in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Trillium tschonoskii Maxim. is one of traditional Chinese medical herbs that has been utilized to treat brain damages and cephalalgia. The neuroprotective effect of total saponins from Trillium tschonoskii rhizome (TSTT) has been demonstrated efficacy in rats following ischemia. However, the axonal remodeling effect of TSTT and the detailed mechanisms after ischemic stroke have not been investigated.

AIM OF THE STUDY

We aimed to estimate therapeutic role of TSTT in axonal remodeling using magnetic resonance imaging (MRI) technique, and explored possible mechanisms underlying this process followed by histological assays in ischemic rats.

METHODS

Male Sprague-Dawley (SD) rats underwent permanently focal cerebral ischemia induced by occluding right permanent middle cerebral artery. TSTT was intragastrically administrated 6 h after surgery and once daily for consecutive 15 days. Neurological function was assessed by the motor deficit score and beam walking test. T2 relaxation mapping and diffusion tensor imaging (DTI) were applied for detecting cerebral tissues damages and microstructural integrity of axons. Luxol fast blue (LFB) and transmission electron microscope (TEM) were performed to evaluate histopathology in myelinated axons. Double immunofluorescent staining was conducted to assess oligodendrogenesis. Furthermore, the protein expressions regarding to axonal remodeling related signaling pathways were detected by Western blot assays.

RESULTS

TSTT treatment (65, 33 mg/kg) markedly improved motor function after ischemic stroke. T2 mapping MRI demonstrated that TSTT decreased lesion volumes, and DTI further confirmed that TSTT preserved axonal microstructure of the sensorimotor cortex and internal capsule. Meanwhile, diffusion tensor tractography (DTT) showed that TSTT elevated correspondent density and length of fiber in the internal capsule. These MRI measurements were confirmed by histological examinations. Notably, TSTT significantly increased Ki67/NG2, Ki67/CNPase double-labeled cells along the boundary zone of ischemic cortex and striatum. Meanwhile, TSTT treatment up-regulated the phosphorylation level of Ser 9 in GSK-3β, and down-regulated phosphorylated β-catenin and CRMP-2 expression.

CONCLUSION

Taken together, our findings indicated that TSTT (65, 33 mg/kg) enhanced post-stroke functional recovery, amplified endogenous oligodendrogenesis and promoted axonal regeneration. The beneficial role of TSTT might be correlated with GSK-3/β-catenin/CRMP-2 modulating axonal reorganization after ischemic stroke.

Mesenchymal Stem/Stromal Cell Therapy in Blood-Brain Barrier Preservation Following Ischemia: Molecular Mechanisms and Prospects

Ischemic stroke is the leading cause of mortality and long-term disability worldwide. Disruption of the blood-brain barrier (BBB) is a prominent pathophysiological mechanism, responsible for a series of subsequent inflammatory cascades that exacerbate the damage to brain tissue. However, the benefit of recanalization is limited in most patients because of the narrow therapeutic time window. Recently, mesenchymal stem cells (MSCs) have been assessed as excellent candidates for cell-based therapy in cerebral ischemia, including neuroinflammatory alleviation, angiogenesis and neurogenesis promotion through their paracrine actions. In addition, accumulating evidence on how MSC therapy preserves BBB integrity after stroke may open up novel therapeutic targets for treating cerebrovascular diseases. In this review, we focus on the molecular mechanisms of MSC-based therapy in the ischemia-induced prevention of BBB compromise. Currently, therapeutic effects of MSCs for stroke are primarily based on the fundamental pathogenesis of BBB breakdown, such as attenuating leukocyte infiltration, matrix metalloproteinase (MMP) regulation, antioxidant, anti-inflammation, stabilizing morphology and crosstalk between cellular components of the BBB. We also discuss prospective studies to improve the effectiveness of MSC therapy through enhanced migration into defined brain regions of stem cells. Targeted therapy is a promising new direction and is being prioritized for extensive research.

Thrombospondin-4 promotes bladder cancer cell migration and invasion via MMP2 production

Bladder cancer (BC) is the second most common urological tumour in Western countries. Approximately, 80% of patients with BC will present with non-muscle invasive bladder cancer (NMIBC), whereas a quarter will have muscle invasive disease (MIBC) at the time of BC diagnosis. However, patients with NMIBC are at risk of BC recurrence or progression into MIBC, and an MIBC prognosis is determined by the presence of progression and metastasis. Matrix metalloproteinase 2 (MMP2), a type of matrix metalloproteinase (MMP), plays a major role in tumour invasion and is well-characterized in BC prognosis. In BC, the mechanisms regulating MMP2 expression, and, in turn, promote cancer invasion, have hardly been explored. Thrombospondin-4 (THBS4/TSP4) is a matricellular glycoprotein that regulates multiple biological functions, including proliferation, angiogenesis, cell adhesion and extracellular matrix modelling. Based on the results of a meta-analysis in the Gene Expression Profiling Interactive Analysis 2 database, we observed that TSP4 expression levels were consistent with overall survival (OS) rate and BC progression, with the highest expression levels observed in the advanced stages of BC and associated with poor OS rate. In our pilot experiments, incubation with recombinant TSP4 promoted the migration and invasion in BC cells. Furthermore, MMP2 expression levels increased after recombinant TSP4 incubation. TSP4-induced-MMP2 expression and cell motility were regulated via the AKT signalling pathway. Our findings facilitate further investigation into TSP4 silencing-based therapeutic strategies for BC.

Progress in Mesenchymal Stem Cell Therapy for Ischemic Stroke

Ischemic stroke (IS) is a serious cerebrovascular disease with high morbidity and disability worldwide. Despite the great efforts that have been made, the prognosis of patients with IS remains unsatisfactory. Notably, recent studies indicated that mesenchymal stem cell (MSCs) therapy is becoming a novel research hotspot with large potential in treating multiple human diseases including IS. The current article is aimed at reviewing the progress of MSC treatment on IS. The mechanism of MSCs in the treatment of IS involved with immune regulation, neuroprotection, angiogenesis, and neural circuit reconstruction. In addition, nutritional cytokines, mitochondria, and extracellular vesicles (EVs) may be the main mediators of the therapeutic effect of MSCs. Transplantation of MSCs-derived EVs (MSCs-EVs) affords a better neuroprotective against IS when compared with transplantation of MSCs alone. MSC therapy can prolong the treatment time window of ischemic stroke, and early administration within 7 days after stroke may be the best treatment opportunity. The deliver routine consists of intraventricular, intravascular, intranasal, and intraperitoneal. Furthermore, several methods such as hypoxic preconditioning and gene technology could increase the homing and survival ability of MSCs after transplantation. In addition, MSCs combined with some drugs or physical therapy measures also show better neurological improvement. These data supported the notion that MSC therapy might be a promising therapeutic strategy for IS. And the application of new technology will promote MSC therapy of IS.

NmFGF1-Regulated Glucolipid Metabolism and Angiogenesis Improves Functional Recovery in a Mouse Model of Diabetic Stroke and Acts via the AMPK Signaling Pathway

Diabetes increases the risk of stroke, exacerbates neurological deficits, and increases mortality. Non-mitogenic fibroblast growth factor 1 (nmFGF1) is a powerful neuroprotective factor that is also regarded as a metabolic regulator. The present study aimed to investigate the effect of nmFGF1 on the improvement of functional recovery in a mouse model of type 2 diabetic (T2D) stroke. We established a mouse model of T2D stroke by photothrombosis in mice that were fed a high-fat diet and injected with streptozotocin (STZ). We found that nmFGF1 reduced the size of the infarct and attenuated neurobehavioral deficits in our mouse model of T2D stroke. Angiogenesis plays an important role in neuronal survival and functional recovery post-stroke. NmFGF1 promoted angiogenesis in the mouse model of T2D stroke. Furthermore, nmFGF1 reversed the reduction of tube formation and migration in human brain microvascular endothelial cells (HBMECs) cultured in high glucose conditions and treated with oxygen glucose deprivation/re-oxygenation (OGD). Amp-activated protein kinase (AMPK) plays a critical role in the regulation of angiogenesis. Interestingly, we found that nmFGF1 increased the protein expression of phosphorylated AMPK (p-AMPK) both in vivo and in vitro. We found that nmFGF1 promoted tube formation and migration and that this effect was further enhanced by an AMPK agonist (A-769662). In contrast, these processes were inhibited by the application of an AMPK inhibitor (compound C) or siRNA targeting AMPK. Furthermore, nmFGF1 ameliorated neuronal loss in diabetic stroke mice via AMPK-mediated angiogenesis. In addition, nmFGF1 ameliorated glucose and lipid metabolic disorders in our mouse model of T2D stroke without causing significant changes in body weight. These results revealed that nmFGF1-regulated glucolipid metabolism and angiogenesis play a key role in the improvement of functional recovery in a mouse model of T2D stroke and that these effects are mediated by the AMPK signaling pathway.

Mechanism of dexmedetomidine regulating osteogenesis-angiogenesis coupling through the miR-361-5p/VEGFA axis in postmenopausal osteoporosis

AIMS

Postmenopausal osteoporosis (PMOP) is a growing health problem affecting many postmenopausal women. This study intended to identify the role of dexmedetomidine (Dex) in osteoporosis (OP).

MAIN METHODS

Microarray analysis was performed for the gene expression profiles of PMOP patients and postmenopausal healthy volunteers, and the most differentially expressed microRNA (miR)-361-5p was verified in clinic, and its diagnostic value in PMOP patients was analyzed. After establishment of OP model by ovariectomy, Dex treatment and overexpression of miR-361-5p or vascular endothelial growth factor A (VEGFA) were performed in OP rats or isolated bone marrow mesenchymal stem cells (BMSCs). Bone mineral density (BMD) related indexes and levels of osteogenesis-angiogenesis related genes were measured. The apoptosis and osteogenic differentiation of BMSCs were detected. After human umbilical vein endothelial cells (HUVECs) and BMSCs were cocultured, the angiogenesis of BMSCs was detected by Matrigel-based angiogenesis experiment.

KEY FINDINGS

miR-361-5p was highly expressed in PMOP patients and OP rats, with good diagnostic effect on PMOP. After Dex treatment, the expressions of miR-361-5p, VEGFA, BMD related indexes were increased in OP rats. In BMSCs, level of osteogenesis-angiogenesis related genes were increased after adding Dex, and the apoptosis was decreased after coculture of HUVECs and BMSCs. miR-361-5p could target VEGFA. After miR-361-5p overexpression + Dex treatment, the indexes related to osteogenesis and angiogenesis in OP rats and BMSCs were decreased, which were reversed after further overexpressing VEGFA.

SIGNIFICANCE

Dex can enhance VEGFA by inhibiting miR-361-5p, and then promote osteogenesis-angiogenesis, thus providing potential targets for PMOP treatment.

The bone marrow-derived mesenchymal stem cells (BMSCs) alleviate diabetic peripheral neuropathy induced by STZ via activating GSK-3β/β-catenin signaling pathway

BACKGROUND

Diabetic peripheral neuropathy, a common complication of diabetic mellitus, has brought a threaten on patients' health. The bone marrow-derived mesenchymal stem cells (BMSCs) were reported to play an important role in diverse diseases. Nevertheless, the specific function of BMSCs in diabetic peripheral neuropathy remained uncharacterized.

METHODS

A wide range of experiments including RT-qPCR, western blot, H&E staining, oxidative stress assessment, measurement of thermal sensitivity, ELISA, urine protein and CCK-8 assays were implemented to explore the function and mechanism of BMSCs in vivo and vitro.

RESULTS

The experimental results displayed that BMSCs improve STZ-induced diabetes symptoms in rats by decreasing blood glucose and urinary protein. Functionally, BMSCs ameliorate oxidative stress, painful diabetic neuropathy, neurotrophic status and angiogenesis in STZ-induced rats. Moreover, BMSCs participate in the regulation of sciatic neuro morphology in diabetic neuropathy rat model. In mechanism, BMSCs alleviate diabetic peripheral neuropathy via activating GSK-3β/β-catenin signaling pathway in rats and improve Schwann's cells viability by activating GSK-3β/β-catenin signaling pathway under high glucose.

CONCLUSIONS

We verified that BMSCs alleviate diabetic peripheral neuropathy of rats induced by STZ via activating GSK-3β/β-catenin signaling pathway, which implied a novel biomarker for diabetic peripheral neuropathy treatment.

Exosomes Secreted From Bone Marrow Mesenchymal Stem Cells Attenuate Oxygen-Glucose Deprivation/Reoxygenation-Induced Pyroptosis in PC12 Cells by Promoting AMPK-Dependent Autophagic Flux

Background: Cerebral ischemia–reperfusion (I/R) injury can lead to severe dysfunction, and its treatment is difficult. It is reported that nucleotide-binding domain and leucine-rich repeat family protein 3 (NLRP3) inflammasome-mediated cell pyroptosis is an important part of cerebral I/R injury and the activation of autophagy can inhibit pyroptosis in some tissue injury. Our previous study found that the protective effects of bone marrow mesenchymal stem cells (BMSCs) in cerebral I/R injury may be associated with the regulation of autophagy. Recent studies have demonstrated that exosomes secreted from BMSCs (BMSC-Exos) may play an essential role in the effective biological performance of BMSCs and the protective mechanism of BMSC-Exos is associated with the activation of autophagy and the remission of inflammation, but it has not been reported in studies of cerebral I/R injury. We aimed to investigate the effects of BMSC-Exos on cerebral I/R injury and determine if the mechanism is associated with the regulation of pyroptosis and autophagic flux.

Method: PC12 cells were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to induce cerebral I/R in vitro and were cocultured with BMSC-Exos. Cell viability was determined with CCK-8 and lactate dehydrogenase (LDH) detection kits. Scanning electron microscopy (SEM), Hoechst 33342/propidium iodide (PI) double staining, 2′,7′-dichlorodihydrofluorescein diacetate assay, immunofluorescence, Western blot, and Enzyme-linked immunosorbent assay (ELISA) were used to detect cell pyroptosis. Furthermore, transmission electron microscopy (TEM), GFP-RFP-LC3 adenovirus transfection, and Western blot were used to detect autophagic flux and its influence on pyroptosis. Finally, coimmunoprecipitation was used to detect the binding interaction between NLRP3 and LC3.

Results: BMSC-Exos increased cell viability in OGD/R. The inhibitory effect of BMSC-Exos on pyroptosis was comparable to the NLRP3 inhibitor MCC950 and was reversed by NLRP3 overexpression. Furthermore, BMSC-Exos promoted autophagic flux through the AMP-activated kinase (AMPK)/mammalian target of the rapamycin pathway, whereas chloroquine, AMPK silencing, and compound C blocked the inhibitory effect on pyroptosis.

Conclusions: BMSC-Exos can protect PC12 cells against OGD/R injury via attenuation of NLRP3 inflammasome-mediated pyroptosis by promoting AMPK-dependent autophagic flux.

1,25(OH)2D3 Strengthens the Vasculogenesis of Multipotent Mesenchymal Stromal Cells from Rat Bone Marrow by Regulating the PI3K/AKT Pathway

Background

Multipotent mesenchymal stromal cells (MSCs) have recently been reported to promote vasculogenesis by differentiating into endothelial cells and releasing numerous cytokines and paracrine factors. However, due to low cell activity, their potential for clinical application is not very satisfactory. This study aimed to explore the effects and mechanisms of 1,25-dihydroxyvitamin D (1,25(OH)₂D₃) on the vasculogenesis of MSCs.

Methods

MSCs were isolated from the femurs and tibias of rats and characterized by flow cytometry. After treatment with different concentrations of 1,25(OH)₂D₃ (0 µM, 0.1 µM and 1 µM), the proliferation of MSCs was analyzed by Cell Counting Kit-8 (CCK-8), and the migratory capability was measured by Transwell assays and cell scratch tests. Capillary-like structure formation was observed by using Matrigel. Western blotting was used to detect the expression of FLK-1 and vWF to investigate the differentiation of MSCs into endothelial cells. Western blotting and gelatin zymography were used to detect the expression and activities of VEGF, MMP-2 and MMP-9 secreted by MSCs under the influence of 1,25(OH)₂D_3. Finally, the VDR antagonist pyridoxal-5-phosphate (P5P) and the PI3K/AKT pathway inhibitor LY294002 were utilized to test the phosphorylation levels of key kinases in the PI3K/AKT pathway by Western blotting and the formation of capillary-like structures in Matrigel.

Results

The proliferation and migratory capability of MSCs and the ability of MSCs to form a tube-like structure in Matrigel were enhanced after treatment with 1,25(OH)₂D₃. Moreover, MSCs treated with 1,25(OH)₂D₃ showed high expression of vWF and Flk-1. There was a significant increase in the expression of VEGF, MMP-2 and MMP-9 secreted by MSCs treated with 1,25(OH)₂D_3, as well as in the activity of MMP-2 and MMP-9. The phosphorylation level of AKT increased with time after 1,25(OH)₂D₃ treatment, while LY294002 weakened AKT phosphorylation. In addition, the ability to form capillary-like structures was reduced when the VDR and PI3K/AKT pathways were blocked.

Conclusion

This study confirmed that 1,25(OH)₂D₃ treatment can strengthen the ability of MSCs to promote vasculogenesis in vitro, and the mechanism may be related to the activation of the PI3K/AKT pathway.

Sijunzi decoction may decrease apoptosis via stabilization of the extracellular matrix following cerebral ischaemia-reperfusion in rats

Neurons undergo degeneration, apoptosis and death due to ischaemic stroke. The present study investigated the effect of Sijunzi decoction (SJZD), a type of traditional Chinese medicine known as invigorating spleen therapy, on anoikis (a type of apoptosis) in rat brains following cerebral ischaemia-reperfusion. Rats were randomly divided into sham, model, nimodipine and SJZD low/medium/high dose groups. A middle cerebral artery occlusion model was established. Neurobehavioural scores were evaluated after administration for 14 days using a five-grade scale. Blood-brain barrier permeability and apoptotic rate were detected using Evans blue (EB) extravasation and TUNEL staining, respectively. Tissue inhibitor of metalloproteinase 1 (TIMP-1), matrix metalloproteinase 9 (MMP-9) and collagen IV (COL IV) were determined using immunohistochemistry. Neurobehavioural scores decreased remarkably in all SJZD and nimodipine groups compared to the model group (P<0.05). Compared with the sham group, EB extravasation was higher in the model group (P<0.01). The amount of EB extravasation decreased in the SJZD high dose and nimodipine groups compared to the model group (P<0.01), and extravasation in the SJZD high dose group was lower than the SJZD low and medium dose groups (P<0.01). TIMP-1 and MMP-9 expression and apoptotic rate increased, but COL IV decreased significantly in the hippocampus of the model group compared to the sham group (P<0.01). TIMP-1 and COL IV expression increased significantly and MMP-9 and apoptotic rate decreased remarkably in all SJZD and nimodipine groups compared to the model group (P<0.01). TIMP-1 and COL IV expression decreased, but MMP-9 expression and apoptotic rate increased in the SJZD low and medium dose groups compared to the SJZD high dose group (P<0.01). SJZD rescued neurons and improved neurobehavioural function in rats following cerebral ischaemia-reperfusion, especially when used at a high dose. The mechanism may be related to protection of the extracellular matrix followed by anti-apoptotic effects.

Development of c‑MET‑specific chimeric antigen receptor‑engineered natural killer cells with cytotoxic effects on human liver cancer HepG2 cells

In recent years, cellular immunotherapy has served an important role in the combined treatment of hepatocellular carcinoma. The possibility of specific cell therapies for the treatment of solid tumours has been further explored following the success of chimeric antigen receptor (CAR)-T cell therapy in the treatment of haematological tumours. The present study aimed to evaluate the specificity and efficiency of c-MET-targeted CAR-NK cell immunotherapy on human liver cancer in vitro. A CAR structure that targeted and recognised a c-MET antigen was constructed. c-MET-CAR was transferred into primary NK cells using lentiviral infection. c-MET-positive HepG2 cells were used as an in vitro study model. The cytotoxicity assay results revealed that c-MET-CAR-NK cells exhibited more specific cytotoxicity for HepG2 cells with high c-MET expression compared with the lung cancer cell line H1299, which has low levels of c-MET expression. The results of the present study demonstrated that c-MET may be a specific and effective target for human liver cancer cell CAR-NK immunotherapy. Based on these results, CAR-NK cell-based immunotherapy may provide a potential biotherapeutic approach for liver cancer treatment in the future.