BACKGROUND:A large number of studies have confirmed that the therapeutic effectiveness of mesenchymal stem cell secretome is comparable to that of mesenchymal stem cells,but the mechanism of its action is still unclear. OBJECTIVE:To summarize the research progress of mesenchymal stem cell secretome in recent years,to investigate the molecular mechanism of its therapeutic effect,to analyze the current problems and to look forward to the future development. METHODS:The terms"exosomes,mesenchymal stem cells secrete,extracellular vesicles,mesenchymal stem cells,mechanism"were used as English search terms in the PubMed database.Articles that were not related to the research purpose of the article and duplicated articles were excluded.At the same time,we combined the method of literature tracking.Finally,109 articles that met the criteria were incuded for the review. RESULTS AND CONCLUSION:(1)The mesenchymal stem cell secretome promotes tissue repair and regeneration through delivering genetic material,immunomodulatory factors,growth factors,etc.to target cells,by activating anti-apoptotic,regulating angiogenesis,modulating fibrosis and pro-survival pathways in target cells.(2)The potential of mesenchymal stem cell secretome in disease therapy has also been confirmed.Numerous research results have shown that mesenchymal stem cell secretome can be used as a new cell-free treatment for inflammatory and degenerative diseases.(3)Mesenchymal stem cell secretome has been engineered to have more efficient therapeutic effects in recent years.However,due to the heterogeneity of the mesenchymal stem cell secretome and the complexity of its components,the exact mechanism of its therapeutic effect is still unclear.(4)At present,further research is needed to identify the key targets of mesenchymal stem cell secretome,and innovative specific and enhanced mesenchymal stem cell secretome should be developed by combining with engineering and genetic engineering technologies in the future.

BACKGROUND:Multiple studies have confirmed that mitogen-activated protein kinase(MAPK)signaling pathway is involved in cell proliferation,and microRNA(miR)is involved in the occurrence and development of hypertrophic scars.Therefore,the role of miR-27a-3p and MAPK signaling pathways in pathological scar formation has been further explored. OBJECTIVE:To explore the effect of miR-27a-3p on the proliferation of human hypertrophic scar fibroblasts through the MAPK signaling pathway. METHODS:The primary fibroblasts were isolated and collected from the skin samples.The primary fibroblasts were observed by inverted microscope and verified by immunofluorescence.The relative expression level of miR-27a-3p in tissues was detected by qRT-PCR.The target genes of hsa-miR-27a-3p were predicted using the database,and then the predicted target genes were enriched by gene ontology function analysis and biological pathway enrichment analysis of the Kyoto Encyclopedia of Genes and Genomes.There were seven groups:blank control,negative control,miR-27a-3p mimic,miR-27a-3p inhibitor,miR-27a-3p mimic+p38 MAPK inhibitor,miR-27a-3p mimic+extracellular regulated protein kinase inhibitor,miR-27a-3p mimic+c-Jun N-terminal kinase inhibitor.Western blot was used to detect the levels of extracellular regulated protein kinase,c-Jun N-terminal kinase inhibitor.and p38 kinase and their phosphorylation levels.Cell counting kit-8 and EdU were used to detect cell proliferation. RESULTS AND CONCLUSION:Compared with normal skin fibroblasts,hypertrophic scar fibroblasts had stronger proliferative activity(P<0.05)and faster proliferation level(P<0.001).Compared with normal skin,miR-27a-3p was highly expressed in hypertrophic scars(P<0.001).Compared with the negative control group,overexpression of miR-27a-3p could promote cell proliferation activity(P<0.001)and proliferation levels(P<0.001).Compared with the negative control group,knockdown of miR-27a-3p could inhibit the proliferation activity(P<0.05)and proliferation levels(P<0.001).Compared with the negative control group,overexpression of miR-27a-3p promoted the phosphorylated levels of extracellular regulated protein kinase,c-Jun N-terminal kinase,and p38 mitogen-activated protein kinase(P<0.05).Compared with the negative control group,knockdown of miR-27a-3p inhibited the phosphorylated levels of extracellular regulated protein kinase,c-Jun N-terminal kinase,and p38 MAPK(P<0.05).Compared with the miR-27a-3p mimic group,specific inhibitors of extracellular regulated protein kinase,c-Jun N-terminal kinase,and p38 MAPK reversed the effects of miR-27a-3p on the proliferative activity(P<0.01)and proliferation level(P<0.001)of fibroblasts.To conclude,these results suggest that miR-27a-3p promotes the proliferation of human hypertrophic scar fibroblasts by activating the MAPK signaling pathway.

OBJECTIVE To investigate the effects of peiminine B （PEI） on Streptococcus pneumoniae （SP）-induced alveolar epithelial cell injury by regulating the Ras-related C3 botulinum toxin substrate 1 in nucleus accumbens （Rac1）/protein kinase B （Akt）/nuclear factor κB （NF-κB） signaling pathway. METHODS Human alveolar epithelial cells （HPAEpiC） were taken and randomly divided into the Control group， SP group （1×108 cfu/mL SP bacterial solution）， low-， medium-， and high-concentration PEI groups （1×108 cfu/mL SP bacterial solution+0.05， 0.10， 0.20 mmol/L PEI）， and high-concentration PEI+Akt activator group （P-H+SC79 group， 1×108 cfu/mL SP bacterial solution+0.20 mmol/L PEI+10 μmol/L SC79）. Except for the Control group， the other groups of cells were treated with SP bacterial solution and/or corresponding drug solution. After 24 h of treatment， the levels of inflammatory factors （interleukin-6， -18， -1β） in the supernatant solution， the contents of oxidative stress indexes [lactate dehydrogenase （LDH）， reactive oxygen species （ROS） and superoxide dismutase （SOD）]， apoptosis rate， as well as the expressions of proliferation/apoptosis-related proteins [cyclin-dependent kinase 1 （CDK1）， B cell lymphoma-2 related X protein （Bax）] and pathway-related proteins （Rac1， Akt， phosphorylated Akt， NF-κB and phosphorylated NF-κB） were detected in each group. RESULTS Compared with the Control group， the levels of inflammatory factors in supernatant solution， LDH and ROS contents， apoptosis rate， the protein expressions of Bax and Rac1 and the phosphorylation levels of Akt and NF-κB in the SP group were significantly increased or up-regulated， while SOD content and the protein expression of CDK1 were significantly decreased or down-regulated （P＜0.05）. Compared with the SP group， the above indexes in PEI groups were significantly improved in a concentration-dependent manner （P＜0.05）. SC79 could significantly reverse the improvement effect of the high concentration of PEI （P＜0.05）. CONCLUSIONS PEI can alleviate SP-induced inflammation and oxidative stress damage of alveolar epithelial cells and inhibit apoptosis， which may be achieved by inhibiting Rac1/Akt/NF-κB signaling pathway.

ObjectiveTo investigate the influence of histone deacetylase 3 (HDAC3) on the occurrence, development of psoriasis-like inflammation in mice, and the relative immune mechanisms. MethodsHealthy C57BL/6 mice aged 6-8 weeks were selected and randomly divided into 3 groups: control group (Control), psoriasis model group (IMQ), and HDAC3 inhibitor RGFP966-treated psoriasis model group (IMQ+RGFP966). One day prior to the experiment, the back hair of the mice was shaved. After a one-day stabilization period, the mice in Control group was treated with an equal amount of vaseline, while the mice in IMQ group was treated with imiquimod (62.5 mg/d) applied topically on the back to establish a psoriasis-like inflammation model. The mice in IMQ+RGFP966 group received intervention with a high dose of the HDAC3-selective inhibitor RGFP966 (30 mg/kg) based on the psoriasis-like model. All groups were treated continuously for 5 d, during which psoriasis-like inflammation symptoms (scaling, erythema, skin thickness), body weight, and mental status were observed and recorded, with photographs taken for documentation. After euthanasia, hematoxylin-eosin (HE) staining was used to assess the effect of RGFP966 on the skin tissue structure of the mice, and skin thickness was measured. The mRNA and protein expression levels of HDAC3 in skin tissues were detected using reverse transcription real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB), respectively. Flow cytometry was employed to analyze neutrophils in peripheral blood and lymph nodes, CD4⁺ T lymphocytes, CD8⁺ T lymphocytes in peripheral blood, and IL-17A secretion by peripheral blood CD4⁺ T lymphocytes. Additionally, spleen CD4⁺ T lymphocyte expression of HDAC3, CCR6, CCR8, and IL-17A secretion levels were analyzed. Immunohistochemistry was used to detect the localization and expression levels of HDAC3, IL-17A, and IL-10 in skin tissues. ResultsCompared with the Control group, the IMQ group exhibited significant psoriasis-like inflammation, characterized by erythema, scaling, and skin wrinkling. Compared with the IMQ group, RGFP966 exacerbated psoriasis-like inflammatory symptoms, leading to increased hyperkeratosis. The psoriasis area and severity index (PASI) skin symptom scores were higher in the IMQ group than those in the Control group, and the scores were further elevated in the IMQ+RGFP966 group compared to the IMQ group. Skin thickness measurements showed a trend of IMQ+RGFP966>IMQ>Control. The numbers of neutrophils in the blood and lymph nodes increased sequentially in the Control, IMQ, and IMQ+RGFP966 groups, with a similar trend observed for CD4⁺ and CD8⁺ T lymphocytes in the blood. In skin tissues, compared with the Control group, the mRNA and protein levels of HDAC3 decreased in the IMQ group, but RGFP966 did not further reduce these expressions. HDAC3 was primarily located in the nucleus. Compared with the Control group, the nuclear HDAC3 content decreased in the skin tissues of the IMQ group, and RGFP966 further reduced nuclear HDAC3. Compared with the Control and IMQ groups, RGFP966 treatment decreased HDAC3 expression in splenic CD4⁺ and CD8⁺ T cells. RGFP966 treatment increased the expression of CCR6 and CCR8 in splenic CD4⁺ T cells and enhanced IL-17A secretion by peripheral blood and splenic CD4⁺ T lymphocytes. Additionally, compared with the IMQ group, RGFP966 reduced IL-10 protein levels and upregulated IL-17A expression in skin tissues. ConclusionRGFP966 exacerbates psoriatic-like inflammatory responses by inhibiting HDAC3, increasing the secretion of the cytokine IL-17A, and upregulating the expression of chemokines CCR8 and CCR6.

Myocardial fibrosis （MF）， characterized by decreased cardiac function and myocardial compliance， is a pathological process and a progression factor in various cardiovascular diseases. The nucleotide-binding domain leucine-rich repeat and pyrin domain-containing receptor 3 （NLRP3） inflammasome is closely related to the development of MF. Recent studies have shown that traditional Chinese medicine （TCM） can regulate the NLRP3 inflammasome to alleviate MF. Based on this， this article systematically summarizes the research progress on the mechanisms by which TCM regulates the NLRP3 inflammasome to improve MF. It is found that active ingredients of TCM， such as alkaloids （lycorine，vincristine，bufalin）， saponins （astragaloside Ⅳ， diosgenin，ginsenoside Rg3）， terpenoids （celastrol，oridonin）， and phenols （polydatin，curcumin，phloridzin） as well as TCM formulas （Zhachong shisanwei pills，Zhilong huoxue tongyu capsules， Luqi formula） can inhibit the activation of the NLRP3 inflammasome， thereby suppressing the release of inflammatory factors such as interleukin-1β and IL-18， reducing inflammatory damage to myocardial tissue， alleviating excessive deposition of the extracellular matrix， and thus exerting the effect of improving MF.

ObjectiveTo observe the clinical efficacy and safety of Modified Guomin Decoction （加味过敏煎， MGD） in patients with mild to moderate atopic dermatitis （AD） of the traditional Chinese medicine （TCM） pattern of heart fire and spleen deficiency， and to explore its possible mechanisms. MethodsIn this randomized， double-blind， placebo-controlled study， 72 patients with mild to moderate AD and the TCM pattern of heart fire and spleen deficiency were randomly divided into a treatment group and a control group， with 36 cases in each group. The treatment group received oral MGD granules combined with topical vitamin E emulsion， while the control group received oral placebo granules combined with topical vitamin E treatment. Both groups were treated twice daily for 4 weeks. Clinical efficacy， TCM syndrome scores， Visual Analogue Scale （VAS） for pruritus， Dermatology Life Quality Index （DLQI） scores， Scoring Atopic Dermatitis （SCORAD） and serum biomarkers， including interleukin-33 （IL-33）， interleukin-1β （IL-1β）， immunoglobulin E （IgE）， and tumor necrosis factor-α （TNF-α） were compared before and after treatment. Safety indexes was also assessed. ResultsThe total clinical effective rates were 77.78% （28/36） in the treatment group and 38.89% （14/36） in the control group， with cure rates of 19.44% （7/36） and 2.78% （1/36）， respectively. The treatment group showed significantly better clinical outcomes compared to the control group （P＜0.05）. The treatment group exhibited significant reductions in total TCM syndrome scores， including erythema， edema， papules， scaling， lichenification， pruritus， irritability， insomnia， abdominal distension， and fatigue scores， as well as reductions in VAS， DLQI， SCORAD， and serum IgE and IL-33 levels （P＜0.05 or P＜0.01）. Compared to the control group， the treatment group had significantly better improvements in all indicators except for insomnia （P＜0.05）. No adverse events occurred in either group. ConclusionMGD is effective and safe in treating mild to moderate AD patients with heart fire and spleen deficiency pattern. It significantly alleviates pruritus， improves TCM syndromes and quality of life， and enhances clinical efficacy， possibly through modulation of immune responses.

Stroke is one of the leading causes of death and disability worldwide， ranking as the second leading cause of mortality globally and the primary cause of adult disability. Its pathological process involves complex cascade mechanisms， with high incidence and disability rates， posing a major threat to human health. According to statistics from the World Health Organization， more than 13 million new cases of stroke occur globally each year， resulting in direct medical costs and socioeconomic burdens amounting to hundreds of billions of dollars. In recent years， breakthroughs in the study of programmed cell death mechanisms have provided new insights into stroke treatment. Among them， ferroptosis， a novel form of cell death driven by iron-dependent lipid peroxidation， has attracted widespread attention in the pathological process of stroke. Ferroptosis is closely associated with iron metabolism disorders， oxidative stress， and lipid peroxidation， and exhibits unique regulatory effects in key pathological processes of stroke， such as ischemia-reperfusion injury， disruption of the blood-brain barrier， and neuronal apoptosis. It plays an important role in post-stroke neurological damage. Chinese medicine， as an essential component of traditional Chinese medicine （TCM）， has demonstrated advantages in modulating ferroptosis and exerting neuroprotective effects. This review systematically summarizes current research on the neuroprotective mechanisms of Chinese medicine compound formulas and monomers through the regulation of ferroptosis pathways in post-stroke conditions， aiming to provide a basis for optimizing clinical treatment strategies and exploring new therapeutic approaches， and to offer new strategies and approaches for stroke treatment.

Stroke is one of the leading causes of death and disability worldwide， ranking as the second leading cause of mortality globally and the primary cause of adult disability. Its pathological process involves complex cascade mechanisms， with high incidence and disability rates， posing a major threat to human health. According to statistics from the World Health Organization， more than 13 million new cases of stroke occur globally each year， resulting in direct medical costs and socioeconomic burdens amounting to hundreds of billions of dollars. In recent years， breakthroughs in the study of programmed cell death mechanisms have provided new insights into stroke treatment. Among them， ferroptosis， a novel form of cell death driven by iron-dependent lipid peroxidation， has attracted widespread attention in the pathological process of stroke. Ferroptosis is closely associated with iron metabolism disorders， oxidative stress， and lipid peroxidation， and exhibits unique regulatory effects in key pathological processes of stroke， such as ischemia-reperfusion injury， disruption of the blood-brain barrier， and neuronal apoptosis. It plays an important role in post-stroke neurological damage. Chinese medicine， as an essential component of traditional Chinese medicine （TCM）， has demonstrated advantages in modulating ferroptosis and exerting neuroprotective effects. This review systematically summarizes current research on the neuroprotective mechanisms of Chinese medicine compound formulas and monomers through the regulation of ferroptosis pathways in post-stroke conditions， aiming to provide a basis for optimizing clinical treatment strategies and exploring new therapeutic approaches， and to offer new strategies and approaches for stroke treatment.

Background: Maturity-onset diabetes of the young (MODY) due to variants of hepatocyte nuclear factor 1-beta (HNF1β) (MODY5) has not been well studied in the Chinese population. This study aimed to estimate its prevalence and evaluate the application of a clinical screening method (Faguer score) in Chinese early-onset diabetes (EOD) patients. Methods: Among 679 EOD patients clinically diagnosed with type 2 diabetes mellitus (age at diagnosis ≤40 years), the exons of HNF1β were sequenced. Functional impact of rare variants was evaluated using a dual-luciferase reporter system. Faguer scores ≥8 prompted multiplex ligation-dependent probe amplification (MLPA) for large deletions. Pathogenicity of HNF1β variants was assessed following the American College of Medical Genetics and Genomics (ACMG) guidelines. Results: Two rare HNF1β missense mutations (E105K and G454R) were identified by sequencing in five patients, showing functional impact in vitro. Another patient was found to have a whole-gene deletion by MLPA in 22 patients with the Faguer score above 8. Following ACMG guidelines, six patients carrying pathogenic or likely pathogenic variant were diagnosed with MODY5. The estimated prevalence of MODY5 in Chinese EOD patients was approximately 0.9% or higher. Conclusion MODY5 is not uncommon in China. The Faguer score is helpful in deciding whether to perform MLPA analysis on patients with negative sequencing results.