Objective To investigate the effects and underlying mechanisms of human placental chorionic plate-derived mesenchymal stem cells (hpcMSCs) on cognitive dysfunction, neuroinflammation, neuronal damage and synaptic plasticity in a mouse model of stroke. Methods A mouse model of middle cerebral artery occlusion (MCAO) was adopted. The mice were randomly divided into three groups: sham operation group, MCAO group and hpcMSCs treatment group, with seven mice in each group. The hpcMSCs treatment group received hpcMSCs transplantation on the 1st, 3rd and 10th day after MCAO. One month after MCAO, the cognitive ability of the mice was evaluated by Morris water maze and Y maze behavioral tests; the morphological changes and synaptic functions of hippocampal neurons were analyzed by HE staining, Nissl staining, Golgi staining and immunofluorescence staining techniques; the density and activation status of microglia was analyzed by Fluorescent labeling method; the levels of tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β) and IL-6 in brain tissue were analyzed by ELISA; the expressions of phosphorylated-mitogen-activated protein kinase kinase 1 (p-MEK1), phosphorylated-extracellular regulated protein kinase (p-ERK) and phosphorylated-cAMP-response element binding protein (p-CREB) and other proteins related to neuroprotection in the signal pathways were detected by Western blotting; and electrophysiological detection was performed using hippocampal slices in vitro. Results Compared with the MCAO group, mice in the hpcMSCs treatment group showed significant improvements, including improved cognitive ability, alleviated neuroinflammation (demonstrated by reduced microglial activation and decreased levels of inflammatory factors TNF-α, IL-1β and IL-6), and increased neuronal density with normalized morphology of neurons in the hippocampal CA1 region. The treatment group also demonstrated a significantly increased number of Nissl-positive cells and density of dendritic spines of hippocampal neurons, along with restored frequency of miniature excitatory postsynaptic potential (mEPSP). Moreover, hpcMSCs treatment significantly increased the expression levels of p-MEK1, p-ERK and p-CREB in the hippocampus. Conclusion Transplantation of hpcMSCs ameliorates cognitive dysfunction and hippocampal neuronal injury in stroke mice through the reduction of neuroinflammation, restoration of hippocampal neuronal function, promotion of synaptic plasticity and activation of the MEK/ERK/CREB signaling pathway. These findings suggest a new potential therapeutic approach for post-stroke neural repair.
Animals ; Hippocampus/physiopathology* ; Mice ; Cognitive Dysfunction/etiology* ; Mesenchymal Stem Cell Transplantation ; Male ; Neurons/metabolism* ; Stroke/metabolism* ; Humans ; Neuroinflammatory Diseases/therapy* ; Female ; Cyclic AMP Response Element-Binding Protein/metabolism* ; Disease Models, Animal ; Mesenchymal Stem Cells/cytology* ; Mice, Inbred C57BL

BACKGROUND:Spleen has the functions of blood storage,hematopoiesis,and immunity.With the increase of age,the structural degeneration and functional decline of spleen lead to the impairment of immune system function,thus accelerating the aging process of the body.The treatment of spleen aging in tree shrews with highly active umbilical cord mesenchymal stem cells has not been reported. OBJECTIVE:To explore the intervention effect and mechanism of highly active umbilical cord mesenchymal stem cells on spleen aging in tree shrews. METHODS:Highly active umbilical cord mesenchymal stem cells were isolated,cultured,and obtained from the umbilical cord tissue of newborn tree shrews by caesarean section.The differentiation abilities of adipogenesis,osteogenesis,and chondrogenesis were detected by three-line differentiation kit.Cell cycle and surface markers were detected by flow cytometry.The second generation of highly active umbilical cord mesenchymal stem cells were transfected with Genechem Green Fluorescent Protein with infection complex values of 100,120,140,160,180,and 200,respectively,to screen the best transfection conditions.After transfection,the fourth generation of highly active umbilical cord mesenchymal stem cells was injected into the tail vein of tree shrews in the elderly treatment group.The young control group and the aged model group were not given special treatment.After 4 months of treatment,the spleen tissue was taken and the structure of the spleen was observed by hematoxylin-eosin staining.β-Galactosidase staining was used to detect the activity of aging-related galactosidase.Immunohistochemical staining was used to detect the expression levels of p21 and p53 proteins.Ki67 and PCNA immunofluorescence staining was used to detect cell proliferation activity.Immunofluorescence staining was used to detect the expression levels of spleen autophagy protein molecules Beclin 1 and APG5L/ATG5.Reactive oxygen species fluorescence staining was used to detect the content of reactive oxygen species in spleen tissue.CD3 immunofluorescence staining was used to detect the change of the proportion of total T lymphocytes.The secretion levels of interleukin 1β and transforming growth factor β1 in spleen were detected by enzyme linked immunosorbent assay.The distribution of highly active umbilical cord mesenchymal stem cells labeled with green fluorescent protein in spleen tissue was observed by DAPI double staining of nucleus. RESULTS AND CONCLUSION:(1)Highly active umbilical cord mesenchymal stem cells grew in a short spindle shape with fish-like growth,with a large proportion of G0/G1 phase,and had the potential to differentiate into adipogenesis,osteogenesis,and chondrogenesis.(2)Multiplicity of infection=140 and transfection for 72 hours were the best conditions for labeling tree shrews highly active umbilical cord mesenchymal stem cells with Genechem Green Fluorescent Protein.(3)Compared with the aged model group,in the aged treatment group,the spleen tissue cells of tree shrews were arranged closely,and the area of white pulp was increased(P<0.01);the boundary between red pulp and white pulp was clear;the proportion of germinal centers did not show statistically significant difference(P>0.05).The activity level of galactosidase related to spleen tissue aging was decreased(P<0.001),and the expression levels of aging protein molecules p21 and p53 were down-regulated(P<0.001).The expression levels of proliferation-related molecules Ki67 and PCNA were up-regulated(P<0.001,P<0.05);expression levels of autophagy-related molecules Beclin 1 and APG5L/ATG5 were up-regulated(P<0.001),and the content of reactive oxygen species decreased(P<0.001),and the proportion of CD3+T cells increased(P<0.05).The secretion level of interleukin 1β in the aging-related secretion phenotype decreased(P<0.001);no significant difference was found in transforming growth factor β1 level(P>0.05).Compared with the young control group,the above indexes were significantly different in the elderly treatment group(P<0.05).(4)Green fluorescent cells labeled with green fluorescent protein were observed in spleen tissue of tree shrews the elderly treatment group by frozen tissue section observation.The results show that intravenous infusion of highly active umbilical cord mesenchymal stem cells can migrate to spleen tissue,inhibit the production of reactive oxygen species,down-regulate the expression of aging-related proteins,induce autophagy,promote cell proliferation,reduce chronic inflammation,and then improve the structure and function of spleen tissue.

BACKGROUND:The cryopreservation technology enables tissues/cells to be stored for a long time in a low-temperature environment while maintaining the integrity of their activity and function,which is of great significance for the construction of cell therapy,tissue engineering and biological sample banks.Cryoprotective agents often contain dimethyl sulfoxide and serum.To avoid the toxic side effects of dimethyl sulfoxide,the complexity of serum components and immune responses,although some finished cryoprotective agents have been marketed,they are faced with many difficulties such as high cost and limited application.Therefore,there is an urgent need to develop a cryoprotective agent with clear components and the ability to solve the above problems.OBJECTIVE:To evaluate the effects of a novel cryoprotectant on cryopreservation efficiency of different tissue and cell sources.METHODS:By applying the novel cryoprotectant as an experimental group with the commercially available and widely used cryoprotectant(control group)to umbilical cord Wharton's jelly tissue,umbilical cord mesenchymal stem cells,umbilical cord blood/peripheral blood mononuclear cells,NK and CIK cells,comparative analyses were conducted in terms of cell morphology,number,viability,surface markers,differentiation potential,and cell-killing toxicity assay before cryopreservation and after resuscitation thawing.We confirmed the cryopreservation effect of the new cryoprotectant and its potential application value.RESULTS AND CONCLUSION:(1)The novel cryoprotectant facilitated the normal growth of cryopreserved Wharton's jelly tissue upon recovery,exhibiting mesenchymal stem cell morphology.No significant differences were observed between the experimental and control groups in terms of cell recovery rate,surface markers,and differentiation potential.(2)There was no significant difference in the number and viability of cells between the experimental group and the control group after cryopreservation of cord blood/peripheral blood mononuclear cells,and the cryo-resuscitated cell numbers and viability of derived NK cells/CIK cells did not show significant difference between the experimental and control groups.(3)For NK cells derived and differentiated from cord blood/peripheral blood mononuclear cells,there was no significant difference in the proportion of CD56+CD16+cell subpopulations between the experimental group and the control group.For CIK cells derived and differentiated from cord blood/peripheral blood mononuclear cells,there was no significant difference in the proportions of CD3+CD8+and CD3+CD56+cell subpopulations between the experimental group and the control group.(4)In terms of cytotoxicity testing,when the effective-target ratio of immune cells and melanoma cell line Mel624 was 20:1,whether it was NK cells/CIK cells derived from cord blood or peripheral blood mononuclear cells,there was no significant difference in the tumoricidal activity of cells between the experimental group and the control group.These findings suggest that the novel cryoprotectant can replace existing commercially available and widely used cryoprotectants,and is applicable to Wharton's jelly tissue,umbilical cord mesenchymal stem cells,umbilical cord blood/peripheral blood mononuclear cells,as well as NK and CIK cells,providing a solid technical foundation for the scaling,standardization,and commercialization of universal cryoprotectants.

Objective To investigate the effects of parecoxib sodium on pain and Toll-like receptor 4(TLR4)/p38 mitogen activated protein kinase(p38MAPK)pathway in rats with femoral fracture.Methods Sixty rats were randomly separated into sham operation group,model group,TLR4 inhibitor(TAK-242)group(3 mg/kg),parecoxib sodium group(10 mg/kg),and parecoxib sodium+TLR4 activator lipopolysaccharide group(10 mg/kg parecoxib sodium+15 mg/kg LPS),with 12 rats in each group.Except for the sham operation group,rats in all other groups were used to establish a femoral fracture model by transverse cutting of the mid femur.After 28 days of treatment in each group,X-rays were used to detect the degree of fracture healing in rats.The mechanical pain threshold(PWMT)and thermal pain threshold(PWTL)of rats were measured.ELISA was applied to detect the levels of tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),and IL-10 in serum.Micro-CT method was applied to detect changes in femoral bone density(BMD),bone volume fraction(BV/TV),trabecular thickness(Tb.Th),and trabecular quantity(Tb.N)in rats.HE staining was applied to observe the pathological changes of bone tissue at the fracture site in rats.Western blot was applied to detect the expression of TLR4/p38MAPK pathway related proteins in bone tissue at the fracture site.Results Compared with the sham operation group,the fracture lines of rats in the model group were obvious,with a small amount of callus growth,the PWMT,PWTL,femoral BMD,BV/TV,Tb.Th,and Tb.N decreased,while the levels of serum IL-6,TNF-α,and IL-10,and the levels of TLR4 and p-p38MAPK/p38MAPK proteins in the bone tissue at the fracture site increased(P＜0.05).Compared with the model group,the fracture lines in the TAK-242 group and the parecoxib sodium group were blurred,and there was an increase in callus growth,the PWMT,PWTL,femoral BMD,BV/TV,Tb.Th,and Tb.N,the serum IL-10 level increased,while the serum IL-6,TNF-αlevels,the TLR4 and p-p38MAPK/p38MAPK protein levels in bone tissue at the fracture site decreased(P＜0.05).LPS could upregulate the phosphorylation levels of TLR4 and p38MAPK,and weaken the relieving effects on anti-inflammatory and pain of parecoxib sodium on fracture rats.Conclusion Paracoxib sodium may alleviate pain and accelerate fracture healing in rats with femoral fractures by inhibiting the TLR4/p38MAPK pathway and suppressing inflammatory responses.

Although clinical evidence suggests that nonalcoholic fatty liver disease is an established major risk factor for heart failure, it remains unexplored whether sleep disorder-caused hepatic damage contributes to the development of cardiovascular disease (CVD). Here, our findings revealed that sleep fragmentation (SF) displayed notable hepatic detrimental phenotypes, including steatosis and oxidative damage, along with significant abnormalities in cardiac structure and function. All these pathological changes persisted even after sleep recovery for 2 consecutive weeks or more, displaying memory properties. Mechanistically, persistent higher expression of nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) in the liver was the key initiator of SF-accelerated damage phenotypes. SF epigenetically controlled the acetylation of histone H3 lysine 27 (H3K27ac) enrichment at the Nox4 promoter and markedly increased Nox4 expression in liver even after sleep recovery. Moreover, fine coordination of the circadian clock and hepatic damage was strictly controlled by BMAL1-dependent Sirtuin 1 (Sirt1) transcription after circadian misalignment. Accordingly, genetic manipulation of liver-specific Nox4 or Sirt1, along with pharmacological intervention targeting NOX4 (GLX351322) or SIRT1 (Resveratrol), could effectively erase the epigenetic modification of Nox4 by reducing the H3K27ac level and ameliorate the progression of liver pathology, thereby counteracting SF-evoked sustained CVD. Collectively, our findings may pave the way for strategies to mitigate myocardial injury from persistent hepatic detrimental memory in diabetic patients.

A major obstacle in type 2 diabetes mellitus (T2DM) is sleep fragmentation (SF), which negatively affects testicular function. However, the underlying mechanisms remain to be elucidated. In this study, we demonstrate that SF induces testicular damage through a mechanism involving lipid metabolism, specifically mediated by melatonin (MEL) receptor 1a (MT1). T2DM mice with SF intervention displayed several deleterious phenotypes such as apoptosis, deregulated lipid metabolism, and impaired testicular function. Unexpectedly, sleep recovery (SR) for 2 consecutive weeks could not completely abrogate SF's detrimental effects on lipid deposition and testicular function. Interestingly, MEL and MT1 agonist 2-iodomelatonin (2IM) effectively improved lipid homeostasis, highlighting MEL/2IM as a promising therapeutic drug for SF-trigged testicular damage. Mechanistically, MEL and 2IM activated FGFR1 and sequentially restrained the crosstalk and physical interaction between TAB1 and TAK1, which ultimately suppressed the phosphorylation of TAK1 to block lipid deposition and cell apoptosis caused by SF. The ameliorating effect of MEL/2IM was overtly nullified in Fgfr1 knockout (Fgfr1-KO ^+/- ) diabetic mice. Meanwhile, testicular-specific overexpression of Tak1 abolished the protective effect of FGF1^mut on diabetic mouse testis. Our findings offer valuable insights into the molecular mechanisms underlying the testicular pathogenesis associated with SF and propose a novel therapeutic approach for addressing male infertility in T2DM.

Objective To investigate the effects of parecoxib sodium on pain and Toll-like receptor 4(TLR4)/p38 mitogen activated protein kinase(p38MAPK)pathway in rats with femoral fracture.Methods Sixty rats were randomly separated into sham operation group,model group,TLR4 inhibitor(TAK-242)group(3 mg/kg),parecoxib sodium group(10 mg/kg),and parecoxib sodium+TLR4 activator lipopolysaccharide group(10 mg/kg parecoxib sodium+15 mg/kg LPS),with 12 rats in each group.Except for the sham operation group,rats in all other groups were used to establish a femoral fracture model by transverse cutting of the mid femur.After 28 days of treatment in each group,X-rays were used to detect the degree of fracture healing in rats.The mechanical pain threshold(PWMT)and thermal pain threshold(PWTL)of rats were measured.ELISA was applied to detect the levels of tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),and IL-10 in serum.Micro-CT method was applied to detect changes in femoral bone density(BMD),bone volume fraction(BV/TV),trabecular thickness(Tb.Th),and trabecular quantity(Tb.N)in rats.HE staining was applied to observe the pathological changes of bone tissue at the fracture site in rats.Western blot was applied to detect the expression of TLR4/p38MAPK pathway related proteins in bone tissue at the fracture site.Results Compared with the sham operation group,the fracture lines of rats in the model group were obvious,with a small amount of callus growth,the PWMT,PWTL,femoral BMD,BV/TV,Tb.Th,and Tb.N decreased,while the levels of serum IL-6,TNF-α,and IL-10,and the levels of TLR4 and p-p38MAPK/p38MAPK proteins in the bone tissue at the fracture site increased(P＜0.05).Compared with the model group,the fracture lines in the TAK-242 group and the parecoxib sodium group were blurred,and there was an increase in callus growth,the PWMT,PWTL,femoral BMD,BV/TV,Tb.Th,and Tb.N,the serum IL-10 level increased,while the serum IL-6,TNF-αlevels,the TLR4 and p-p38MAPK/p38MAPK protein levels in bone tissue at the fracture site decreased(P＜0.05).LPS could upregulate the phosphorylation levels of TLR4 and p38MAPK,and weaken the relieving effects on anti-inflammatory and pain of parecoxib sodium on fracture rats.Conclusion Paracoxib sodium may alleviate pain and accelerate fracture healing in rats with femoral fractures by inhibiting the TLR4/p38MAPK pathway and suppressing inflammatory responses.

BACKGROUND:With the increase of age,the function of bone marrow-derived mesenchymal stem cells is gradually reduced,and delaying the aging of bone marrow-derived mesenchymal stem cells itself has become an important topic.OBJECTIVE:To explore ways to delay the aging of bone marrow-derived mesenchymal stem cells by changing the expression of telomerase Cajal body protein 1(TCAB1)gene.METHODS:Mouse bone marrow-derived mesenchymal stem cells were cultured by cell adhesion method.TCAB1 gene in bone marrow-derived mesenchymal stem cells was overexpressed and interfered by recombinant lentivirus technique.The expression of aging related genes P16,P21,P53,and P27 was detected by qPCR.The relative length of telomeres was detected by qPCR.The expression of aging proteins P16,P21,P53,and P27 was detected by western blot assay.Cell proliferation was detected by CCK-8 assay.Annexin V-PE/7-AAD apoptosis kit was used to detect the degree of cell apoptosis.RESULTS AND CONCLUSION:Bone marrow-derived mesenchymal stem cell lines overexpressing TCAB1 gene had decreased expression of senescence related genes and proteins,increased Telomere relative length,stronger cell proliferation,less apoptosis,and a youthful state.The expression of age-related genes and proteins in bone marrow mesenchymal stem cells interfering with TCAB1 gene increased,and the relative telomere length decreased;cell proliferation ability was weak;cell apoptosis was more,and cells showed senescence.These results indicate that increasing the expression of TCAB1 in an appropriate range can delay the rate of cell senescence.

BACKGROUND:Studies have shown that intradiscal injection of syringin solution can improve the structure and function of the intervertebral disc,prevent and slow down the process of intervertebral disc degeneration in rats.However,the biological half-life of syringin is short and it is difficult for it to continue to play a role in the intervertebral disc.Its bioavailability needs to be further improved.OBJECTIVE:To observe the effect of syringin-chitosan hydrogel on intervertebral disc degeneration in rats and the mechanism of syringin in the treatment of intervertebral disc degeneration.METHODS:(1)Cell experiment:Passages 2-5 rat nucleus pulposus cells were divided into four groups for treatment.The normal control group did not undergo any treatment.The degeneration group was added with interleukin-1β(to establish the intervertebral disc degeneration cell model).The drug group was added with interleukin-1β and syringing.The inhibitor group was added with interleukin-1β,syringing,and phosphatidylinositol 3-kinase(PI3K)inhibitor LY294002.After 24 hours of treatment,apoptosis,extracellular matrix,oxidative stress,and apoptosis-related proteins and PI3K/protein kinase B(AKT)signaling pathway proteins were detected respectively.(2)Animal experiment:Syringin-chitosan hydrogels were prepared,and the micromorphology and slow-release properties of the hydrogels were tested.Thirty SD rats were randomly divided into model control group,model intervention group,hydrogel group,syringin solution group,and syringin hydrogel group,with 6 rats in each group.The intervertebral disc degeneration model was established by the acupuncture method.Immediately after model establishment,the rats in model intervention group,hydrogel group,syringin solution group,and syringin hydrogel group were injected with PBS,chitosan hydrogel,syringin solution,and syringin-chitosan hydrogel,respectively.The samples were taken 8 weeks after modeling for histological detection.RESULTS AND CONCLUSION:(1)Cell experiment:Compared with the normal control group,apoptosis rate,reactive oxygen species level,and expression of BAX,cleaved caspase-9,cleaved caspase-3,and matrix metalloproteinase 13 protein were increased in the nucleus pulpocytes in the degeneration group(P＜0.05),and the expression levels of p-PI3K,p-AKT,BCL-2,and type Ⅱ collagen were decreased(P＜0.05).Superoxide dismutase activity decreased(P＜0.05).Compared with the degeneration group,apoptotic rate,reactive oxygen species level,and expression of BAX,cleaved caspase-9,cleaved caspase-3,and matrix metalloproteinase 13 protein were decreased in the syringin solution and syringin solution groups(P＜0.05),and expression levels of p-PI3K,p-AKT,BCL-2,and type Ⅱ collagen were increased(P＜0.05).Superoxide dismutase activity increased(P＜0.05).LY294002 could partially inhibit the effect of syringin.(2)Animal experiment:Syringin-chitosan hydrogel had a loose porous structure and good slow-release performance.Hematoxylin-eosin and safranin O-fast green staining showed that compared with the model control group and model intervention group,chitosan hydrogel,syringin solution and syringing-chitosan hydrogel could improve the intervertebral disc degeneration in different degrees,and the therapeutic effect of syringing-chitosan hydrogel was better than that of hydrogel and drug solution alone.(3)These findings indicate that syringin can regulate apoptosis of nucleus pulposus cells and extracellular matrix degradation induced by oxidative stress by activating PI3K/AKT signaling pathway,thus delaying disc degeneration.Compared with syringin injection alone,syringin loading in chitosan hydrogel can further delay the progression of intervertebral disc degeneration in rats.

Objective To investigate the changes of inflammatory factors in bronchoalveolar lavage fluid(BALF),lung tissue,and serum of a rat pneumonia model induced by inhalation of lipopolysaccharides(LPS).Methods Three days after modeling by LPS 4 mg/mL inhalation,15 min/d,was conducted while monitoring the particle size distribution and aerosol concentration of LPS,the degree of inflammation in lung tissues of rats in each group was observed via HE staining,and neutrophils in BALF were counted by microscope.The contents of interferon gamma(IFN-γ),interleukin-1 beta(IL-1 β),IL-4,IL-5,IL-6,IL-10,IL-13,tumor necrosis factor alpha(TNF-α),and KC/GRO in lung tissue,serum,and BALF were detected by Meso Scale Discovery.Results The lung histopathology of model rats displayed focal and diffuse alveolar epithelial necrosis with shedding and the aggregation and infiltration of inflammatory cells.The particle size distribution of atomized LPS was as follows,Dv(10)=0.6974μm,Dv(50)=3.387 μm,Dv(90)=8.836 μm.The aerosol concentration of LPS was 4.08 g/m3,and the calculated inhalation dose for rats was 47.10 mg/kg.The neutrophil count(P＜0.01)and contents of IL-1β,IL-6,and TNF-α(P＜0.05,P＜0.001,P＜0.001)in the BALF,and the contents of IL-1β,IL-6,and KC/GRO in lung tissue(P＜0.01,P＜0.05,P＜0.01),of model rats were significantly increased.No biologically significant changes were observed in inflammatory factor levels in the serum.Conclusions In the acute pneumonia model induced by inhalation of LPS,significant changes in inflammatory factors such as IL-1β,IL-6,KC/GRO,and TNF-α were observed in both lung tissue and bronchoalveolar lavage fluid(BALF),while no notable changes in these inflammatory factors were detected in serum.This indicates that the inflammation responses are primarily localized in the lungs.