BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

Objective:To establish an evaluation model for the radon reduction effect of activated carbon adsorption in localized underground spaces, to guide the rational application of the activated carbon adsorption method for radon reduction in localized underground spaces.Methods:For both intermittent and continuous adsorption-based radon reduction method in localized underground spaces, a theoretical model was constructed for evaluating the of radon reduction effec. By means of this modle, the influence factors on the radon reduction effect were analyzed such as radon concentration, space volume, and air exchange rate with the external environment. Experimental validation of the theoretical model was conducted under typical conditions.Results:The radon exhalation rate from concrete surface in localized underground spaces was inversely linear relationship with the indoor radon concentration. However, the slope of this relationship was very small: when the radon concentration decreased from 2 018 Bq/m 3 to 0, the exhalation rate only increased slightly from 4.20 to 4.46 Bq·m -2·h -1, indicating a minimal change. At the same air exchange rate and in the same space volume, the initial radon concentration had little impact on the adsorption-based radon reduction effect, thus suggesting that the radon generation rate from the enclosure surface could be negligible in the evaluation. In contrast, the adsorption flow rate of a radon reduction device and the air exchange rate between the localized spaces and surrounding environment had significant fluence on radon reduction effect. In the same sealed space and at the same adsorption flow rate, the difference in effect between intermittent and continuous adsorption method was of insignificance. However, in localized spaces with connectivity to surrounding environment, the continuous adsorption significantly outperforms intermittent adsorption, achieving faster radon reduction and better suitability for larger spaces. Simulated experiments validated that the theoretical model for evaluating adsorption-based radon reduction effect was reliable. Conclusions:The research findings provide theoretical guidance on selecting appropriate adsorption-based radon reduction devices for localized underground spaces of different volumes and varing connectivity conditions, in order to reduce the radon concentration within localized spaces to expected levels.

Tongue squamous cell carcinoma is the most frequent malignant tumor in the oral cavity.The incidence of occult metastasis in early-stage tongue squamous cell carcinoma ranges from 19.81%to 61.8%.The sensitivity,specificity,and accuracy of currently employed diagnostic techniques vary among different research centers.Cervical lymph nodes in tongue squamous cell carcinoma exhibit certain regu-larities,with metastasis primarily occurring in ipsilateral levels Ⅰ,Ⅱ,and Ⅲ,and occasional occurrence of skip metastasis.Occult metastasis to cervical lymph nodes in tongue squamous cell carcinoma is influenced by various factors.The treatment approach for the neck remains controversial,with options including selective neck dissection,observation,and sentinel lymph node biopsy.This review aims to elaborate on the incidence of occult lymph node metastasis in patients with tongue squamous cell carcinoma,the distribution patterns of metastatic lymph nodes,the value of various diagnostic techniques in detecting occult metastasis,risk factors for occult metastasis,and strategies for neck management.

Cardiovascular diseases have become the leading cause of mortality worldwide.The gut microbiota and its metabolites play an important role in the occurrence and development of cardiovascular diseases,and an imbalance of gut microbiota and its metabolites can promote the progression of cardiovascular diseases.Phenylacetylglutamine is a phenyl-alanine metabolite of intestinal flora.More and more studies have shown that phenylacetylglutamine is an independent risk factor of cardiovascular diseases and a potential biomarker of cardiovascular diseases.It is involved in the pathogenesis of cardiovascular diseases,such as arrhythmia,heart failure,atherosclerosis,etc.Therefore,interventions targeting pheny-lacetylglutamine are expected to become a new strategy for treating cardiovascular diseases.This review focuses on the role of phenylacetylglutamine in the occurrence and development of several common cardiovascular diseases.

As cardiac magnetic resonance imaging technology advances,T1 mapping has emerged as a non-invasive method offering visual and quantitative insights into myocardial fibrosis,edema,and infiltration associated with cardiac dis-eases.The application of T1 mapping in myocardial diseases allows for evaluating both focal and diffuse myocardial fibro-sis,playing a crucial clinical role in the differentiation,treatment,and prognostic risk assessment of diseases.This arti-cle aims to provide a thorough overview of the clinical applications of T1 mapping in patients with cardiomyopathy,summa-rizing the commonly employed scanning techniques and imaging principles.

Aim To investigate whether adipose differentiation-related proteins promote macrophage lipid accu-mulation by upregulating acyl-CoA synthetase long-chain family member 3(ACSL3)expression through PI3K/Akt.Methods The experiments were divided into 24 h group,different PLIN2 expression groups,HA-PLIN2+SC97 group and HA-PLIN2+LY294002 group.Western blot was used to detect the protein expression of PLIN2,Akt,p-Akt and ACSL3 in cells,RT-qPCR was used to detect the mRNA level of PLIN2 in cells,and oil red O was used to observe the degree of lipid accumulation in cells.Results The protein expression levels of Akt,p-Akt and ACSL3 in macrophages overex-pressing PLIN2 were significantly increased(P＜0.05),and p-Akt nuclear translocation was increased,with fluorescence labeling of PLIN2 and Akt overlapping.After adding the PI3K/Akt agonist SC97 to macrophages overexpressing PLIN2,the expression level of ACSL3 significantly increased(P＜0.05),and the degree of intracellular lipid accumulation in-creased;After adding the PI3K/Akt inhibitor LY294002 to macrophages overexpressing PLIN2,the expression level of AC-SL3 significantly decreased(P＜0.05),and the degree of intracellular lipid accumulation decreased.Conclusion PLIN2 upregulates ACSL3 expression through PI3K/Akt,thereby promoting macrophage lipid accumulation.

BACKGROUND:Adipose tissue-derived mesenchymal stem cells release a large amount of exosomes to participate in various pathophysiological processes,but the impact and precise mechanism of exosomes derived from adipose tissue-derived mesenchymal stem cells on autophagy of hepatic stellate cells have not been fully elucidated.OBJECTIVE:To explore the targeted regulatory effect and molecular mechanism of adipose tissue-derived mesenchymal stem cell-derived exosomes on autophagy of hepatic stellate cells through miR-15a-5p.METHODS:Adipose tissue was collected from inguinal region of 8-week male C57BL/6 mice.Adipose tissue-derived mesenchymal stem cells were extracted by collagenase digestion.Adipose tissue-derived mesenchymal stem cell-derived exosomes were extracted by ultracentrifugation.Mouse liver tissue was obtained,and hepatic stellate cells were isolated and extracted using collagenase perfusion digestion and density gradient centrifugation.The experiment was divided into two groups.In control group,hepatic stellate cells were cultured alone for 48 hours.In the exosome group,hepatic stellate cells were co-cultured with adipose tissue-derived mesenchymal stem cell-derived exosomes for 48 hours.The effects of exosomes on hepatic stellate cell proliferation,activation,autophagy,and expression of fibrosis markers were detected by western blot assay,RT-qPCR,and immunofluorescence staining.RT-qPCR and western blot assay were used to detect the effect of exosomes on the mRNA and protein expression of miR-15a-5p and the downstream signaling pathway Bcl-2,Beclin-1,and Rubicon in hepatic stellate cells.RESULTS AND CONCLUSION:(1)Compared with the control group,the ratio of autophagy markers LC3-Ⅱ expression decreased,the number of autophagosome was also significantly decreased,and the intracellular lipid droplets were regenerated,simultaneously,cell volume diminished with the weakening of proliferation in hepatic stellate cells of the exosome group,indicated that the hepatic stellate cell activation was significantly inhibited.(2)Compared with the control group,the expressions of α-smooth actin and type Ⅰ collagen were significantly decreased(P＜0.01),and the expression of miR-15a-5p was significantly increased in hepatic stellate cells of the exosome group(P＜0.01).At the same time,the expression of its downstream target gene Bcl-2 was significantly decreased(P＜0.01),while the expressions of autophagy genes Beclin-1 and Rubicon were significantly increased in hepatic stellate cells of the exosome group(P＜0.01).The results indicate that adipose tissue-derived mesenchymal stem cell-derived exosomes inhibits the expression of Bcl-2 in hepatic stellate cells by targeting miR-15a-5p and increases the expression of downstream autophagy genes Beclin-1 and Rubicon,thereby inhibiting the autophagy of hepatic stellate cells.

Diabetic cardiomyopathy(DCM)is a prevalent cardiovascular complication associated with diabe-tes,which is characterized by abnormalities in heart structure and function.Chronic inflammation,which is mediated by the nuclear factor-κB(NF-κB)signaling pathway,is pivotal in the onset and progression of DCM.NF-κB can be activated by diabetes-related factors,including hyperglycemia,oxidative stress,and endoplasmic reticulum stress,which in turn promote the expression of inflammatory cytokines,chemokines,and adhesion molecules.This cascade leads to cardiac in-flammation,fibrosis,and apoptosis.Therefore,we summarized the role of the NF-κB signaling pathway in DCM,particu-larly its activation mechanisms and downstream reactions.The regulatory effects of cytokines,receptors,reactive oxygen species,and other factors involved in NF-κB activation were also analyzed.In addition,potential therapeutic strategies to modulate NF-κB activity,including natural compounds,synthetic inhibitors,gene therapy,and monoclonal antibodies,were summarized in this study.Targeting the NF-κB signaling pathway can mitigate the inflammatory response and en-hance cardiac function in patients with DCM.However,the development of selective and effective NF-κB inhibitors,along with the validation of their safety and efficacy through clinical trials,remains a critical focus for future research.

Aim To investigate the role and regulatory mechanism of CREB regulated transcription coactivator 2(CRTC2)in cardiomyocyte hypertrophy.Methods A pathological cardiomyocyte hypertrophy model was established in C57BL/6 mice by intraperitoneal injection of isoproterenol(ISO),the expression of CRTC2 in cardiac tissue was detec-ted by Western blot.The CRTC2 knockout mice model was constructed,the cardiac function of mice was detected by small animal echocardiography,the collagen fiber content in mice cardiac tissue was detected by Masson staining,the car-diomyocyte hypertrophy related proteins:skeletal muscle α1-actin(ACTA1)and brain natriuretic peptide(BNP),as well as ferroptosis related proteins:acyl-CoA synthetase long chain family member 4(ACSL4),solute carrier family 7 member 11(SLC7A11)and glutathione peroxidase 4(GPX4)in mice cardiac tissue were detected by Western blot,the iron ion content in mice cardiac tissue was detected by iron ion kit,to evaluate the correlation between CRTC2 and cardiomyocyte hypertrophy and ferroptosis.H9c2 cells were induced by ISO to construct an in vitro model of cardiomyocyte hypertrophy,the protein expressions of CRTC2,ACTA1,BNP,ACSL4,SLC7A11 and GPX4 were detected after intervention with fer-roptosis inhibitor ferrostatin-1(Fer-1).H9c2 cells with CRTC2 overexpression induced by ISO were used to construct an in vitro model of cardiomyocyte hypertrophy,the related indicators of cardiomyocyte hypertrophy and ferroptosis were detec-ted to explore the mechanism of CRTC2 in cardiomyocyte hypertrophy.Results Compared with the control group,the expression of CRTC2 protein in the cardiac tissue of ISO induced cardiomyocyte hypertrophy mice was increased(P＜0.05).Compared with wild-type mice,CRTC2-/-mice showed worsened cardiac function,manifested as increased left ventricular end-diastolic diameter(LVEDD),left ventricular end-systolic diameter(LVESD),left ventricular posterior wall thickness(LVPWT),heart weight/tibia length(HW/TL)and heart weight/body weight(HW/BW),decreased short axis shortening(FS)and ejection fraction(EF),increased collagen fiber content in cardiac tissue,upregulated ex-pression of cardiomyocyte hypertrophy-related proteins ACTA1 and BNP,increased mRNA and protein expression of ferrop-tosis-related protein ACSL4,decreased mRNA and protein expression of SLC7A11 and GPX4,and elevated iron ion content in cardiac tissue(P＜0.05 or P＜0.01).In vitro experiments showed that compared with ISO group,the ISO+Fer-1 group had no significant change in CRTC2 protein expression(P＞0.05),the expression of ACTA1 and BNP protein decreased,the surface area of cardiomyocyte reduced,the expression of ACSL4 protein decreased,and the expression of SLC7A11 and GPX4 proteins increased(P＜0.05 or P＜0.01).Compared with the ISO group,the LV-CRTC2+ISO group showed a decrease in surface area of cardiomyocytes(P＜0.01),a decrease in ACTA1,BNP and ACSL4 protein ex-pression,an increase in SLC7A11 and GPX4 protein expression,and a decrease in ROS and iron ion content(P＜0.05 or P＜0.01).Conclusion CRTC2 alleviates cardiomyocyte hypertrophy and protect cardiac function by suppressing fer-roptosis in cardiomyocytes.