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:Adipose-derived stem cells have anti-aging effects,but whether adipose-derived stem cells from donors of different ages are different needs further study. OBJECTIVE:To compare the biological properties of adipose-derived stem cells in old and young mice. METHODS:Adipose-derived stem cells were extracted from adipose tissue of C57BL mice aged 8 and 14 weeks,respectively.The differences of cell cycle,apoptosis,and proliferation of adipose-derived stem cells in old and young mice were compared.The expression levels of aging-related P21 and P27 genes and proteins of adipose-derived stem cells in old and young mice were detected by quantitative PCR and western blot assay. RESULTS AND CONCLUSION:Compared with old mouse adipose-derived stem cells,young mouse adipose-derived stem cells were more active,more regular in morphology,less apoptosis,faster proliferation,and lower in expression of age-related P21 and P27 genes and proteins.It has been proven that adipose-derived stem cells from young mice have better anti-aging effects.

BACKGROUND:As an emerging treatment method,stem cell therapy is expected to improve the ovarian environment,delays the aging of ovarian granulosa cells,and brings new hope to older pregnant women.OBJECTIVE:To review the mechanism and research progress of stem cells against ovarian granulosa cell senescence.METHODS:CNKI and PubMed databases were retrieved for articles on stem cell therapy for ovarian granulosa cell senescence.Chinese and English search terms were"stem cells,ovary granulosa cells,aging."Finally,67 articles were included for analysis.RESULTS AND CONCLUSION:(1)This review summarizes five mechanisms of ovarian granulosa cell senescence:DNA damage and decreased repair capacity,oxidative stress,impaired mitochondrial function,inflammatory response,and changes in hormone levels.(2)This article summarizes five main mechanisms of stem cells in the treatment of ovarian granulosa cell senescence:promoting proliferation and inhibiting apoptosis,differentiation potential and regeneration ability,secreting factors,anti-oxidation,anti-inflammatory response,and immune regulation.(3)At present,there are various types of stem cells that can cooperate to treat ovarian granulosa cell senescence through a variety of ways,and stem cell therapy has broad prospects in restoring female fertility.

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.

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.

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:As an emerging treatment method,stem cell therapy is expected to improve the ovarian environment,delays the aging of ovarian granulosa cells,and brings new hope to older pregnant women.OBJECTIVE:To review the mechanism and research progress of stem cells against ovarian granulosa cell senescence.METHODS:CNKI and PubMed databases were retrieved for articles on stem cell therapy for ovarian granulosa cell senescence.Chinese and English search terms were"stem cells,ovary granulosa cells,aging."Finally,67 articles were included for analysis.RESULTS AND CONCLUSION:(1)This review summarizes five mechanisms of ovarian granulosa cell senescence:DNA damage and decreased repair capacity,oxidative stress,impaired mitochondrial function,inflammatory response,and changes in hormone levels.(2)This article summarizes five main mechanisms of stem cells in the treatment of ovarian granulosa cell senescence:promoting proliferation and inhibiting apoptosis,differentiation potential and regeneration ability,secreting factors,anti-oxidation,anti-inflammatory response,and immune regulation.(3)At present,there are various types of stem cells that can cooperate to treat ovarian granulosa cell senescence through a variety of ways,and stem cell therapy has broad prospects in restoring female fertility.

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.

Abstract Social withdrawal is a kind of behavioral inhibition in social situations, which may increase the risk for maladjustment, internalizing and externalizing problems, interfering with psychological development and healthy growth. With the deepening understanding in sociology of development, child social withdrawal has gradually received extensive attention from scholars across the world. Understanding the phenomenon of child social withdrawal is important for in depth follow up research. Based on the literature review, the paper aims to summarize the types, mechanisms and influencing factors of social withdrawal in children, in order to provide scientific basis for formulating prevention strategies and early intervention programs in the future.

Urea transporters (UT) play a vital role in the mechanism of urine concentration and are recognized as novel targets for the development of salt-sparing diuretics. Thus, UT inhibitors are promising for development as novel diuretics. In the present study, a novel UT inhibitor with a diarylamide scaffold was discovered by high-throughput screening. Optimization of the inhibitor led to the identification of a promising preclinical candidate,