Metabolic dysfunction-associated steatotic liver disease (MASLD) has become the most prevalent chronic liver disease worldwide, affecting approximately 32%-38% of the adult population and posing a growing public health burden. MASLD represents a continuous disease spectrum ranging from simple steatosis to metabolic dysfunction-associated steatohepatitis (MASH), progressive hepatic fibrosis, cirrhosis, and ultimately hepatocellular carcinoma (HCC). The pathological core of MASLD lies in disruption of hepatic lipid metabolic homeostasis, characterized by an imbalance among de novo lipogenesis, fatty acid β-oxidation, and very-low-density lipoprotein (VLDL)-mediated lipid export. This metabolic disequilibrium subsequently drives inflammatory injury and fibrotic progression. Among the multiple regulatory pathways involved, thyroid hormone (TH) signaling has emerged as a central regulator of hepatic metabolic homeostasis. The liver is a major peripheral target organ of TH action, where TH predominantly exerts its metabolic effects through thyroid hormone receptor β (TRβ). Large-scale epidemiological studies and meta-analyses have demonstrated that hypothyroidism is significantly associated with increased MASLD prevalence, more severe histological injury, and advanced hepatic fibrosis, suggesting that dysregulation of TH signaling may participate throughout the entire MASLD disease spectrum. At the molecular level, TH regulates hepatic lipid metabolism by coordinating suppression of lipogenesis, enhancement of mitochondrial fatty acid oxidation, and promotion of VLDL assembly and secretion through integrated genomic actions of the T3-TRβ axis and non-genomic signaling pathways. Across different stages of MASLD, TH signaling exerts stage-dependent protective effects. In the steatosis stage, TH improves metabolic flexibility by modulating insulin sensitivity, glucose metabolism, and lipid droplet clearance, thereby alleviating early lipotoxic stress. During progression to MASH, TH attenuates inflammatory amplification by improving mitochondrial homeostasis, suppressing activation of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome, and modulating the gut-liver axis microenvironment. In advanced stages, TH signaling influences hepatic stellate cell activation and extracellular matrix deposition, partly through interaction with the transforming growth factor-β (TGF-β)/SMAD pathway, while alterations in intrahepatic TH availability, mediated by dynamic changes in iodothyronine deiodinase 1 (DIO1), contribute to fibrosis progression and hepatocellular dedifferentiation. In hepatocellular carcinoma, coordinated downregulation of TRβ and DIO1 establishes a tumor-associated hypothyroid state that promotes metabolic reprogramming and tumor progression. The clinical relevance of TH signaling in MASLD has been underscored by the recent approval of Resmetirom, a liver-targeted TRβ‑selective agonist, for the treatment of non-cirrhotic MASH with moderate-to-severe fibrosis (F2-F3). This approval represents a landmark transition from mechanistic understanding to metabolism-centered precision therapy in MASLD. Clinical trials have demonstrated that Resmetirom not only improves key histological endpoints, including MASH resolution and fibrosis regression, but also favorably modulates atherogenic lipid profiles, highlighting the therapeutic potential of selectively targeting hepatic TH pathways. This review systematically summarizes the multidimensional regulatory roles of TH across the MASLD disease spectrum and discusses emerging diagnostic and therapeutic implications of TH-based interventions, aiming to inform future mechanistic research and optimize clinical management strategies.

ObjectiveTo investigate the potential mechanism of Danggui Buxuetang （DBT） in the treatment of vascular dementia （VAD）. MethodsSixty male SD rats were randomly assigned to the sham-operated group， model group， DBT low-， medium-， and high-dose groups， and the donepezil group. Except for the sham-operated group， rats in all other groups underwent bilateral common carotid artery ligation. After successful modeling， DBT was administered at doses of 9.2， 18.4， 36.8 g·kg^-1 for the low-， medium-， and high-dose groups， respectively， while the donepezil group received 3 mg·kg^-1 donepezil solution by gavage once daily. After 4 consecutive weeks of drug treatment， rats underwent the Morris water maze test， novel object recognition test， Nissl staining to observe hippocampal neurons， and immunofluorescence staining to detect the expression of neuronal nuclear protein （NeuN） in the hippocampus. Western blot was used to assess the expression of PTEN-induced kinase 1 （PINK1）， Parkin， microtubule-associated protein 1 light chain 3Ⅱ （LC3Ⅱ）， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax）. Transmission electron microscopy was used to observe hippocampal neuronal ultrastructure. Real-time PCR was used to detect the expression of NADPH oxidase subunits p22^phox and p47^phox in hippocampal tissues. The levels of malondialdehyde （MDA）， glutathione （GSH）， superoxide dismutase （SOD）， and total antioxidant capacity were measured to evaluate oxidative stress levels. ResultsIn the Morris water maze test， escape latency changed significantly over time in all groups except the model group. Compared with the sham-operated group， the model group showed significantly prolonged escape latency （P<0.01）. Compared with the model group， rats in the DBT groups and the donepezil group exhibited significantly shorter escape latency （P<0.05， P<0.01）. The number of crossings over the original platform was significantly reduced in the model group compared with the sham-operated group （P<0.01）， whereas rats in the DBT and donepezil groups showed significantly increased platform crossings compared with the model group （P<0.05， P<0.01）. Compared with the sham-operated group， exploration time of new objects was significantly reduced in the model group （P<0.01）. Compared with the model group， exploration time of new objects increased significantly in the medium- and high-dose DBT groups and the donepezil group （P<0.05， P<0.01）， while no significant change was observed in the low-dose DBT group. Compared with the high-dose DBT group， rats in the donepezil group had significantly prolonged escape latency and reduced platform crossings and new-object exploration time （P<0.05）. Nissl staining showed decreased density of healthy neurons in the CA1 and CA3 regions of the hippocampus in the model group， with loss of Nissl bodies and nuclear atrophy or disappearance. In the high-dose DBT group， neuronal density in CA1 and CA3 increased， with neurons arranged closely and displaying normal morphology. Immunofluorescence showed that compared with the sham-operated group， the hippocampal NeuN⁺ cell count in the VAD model group was significantly decreased（P<0.01）， compared with the VAD model group， the hippocampal NeuN⁺ cell count in the high-dose DBT group was significantly increased（P<0.01）. Compared with the sham-operated group， the expression of PINK1， Parkin， LC3Ⅱ， and Bax proteins was significantly increased（P<0.01）， while the expression of Bcl-2 was significantly decreased in the VAD model group（P<0.01）. Compared with the VAD model group， the high-dose DBT group showed significantly decreased expression of PINK1， Parkin， LC3Ⅱ， and Bax proteins（P<0.01）and significantly upregulated Bcl-2 expression（P<0.01）. The medium-dose DBT group exhibited significantly reduced expression of Parkin， LC3Ⅱ， and Bax proteins（P<0.05，P<0.01） and significantly increased Bcl-2 expression（P<0.01）， while no statistically significant differences were observed in the low-dose DBT group. Transmission electron microscopy showed mitochondrial pyknosis， thickened cristae， increased electron density， and the presence of mitochondrial autophagy in the model group. In contrast， hippocampal neurons in the high-dose DBT group contained abundant mitochondria with intact morphology， clear cristae， and uniform matrix. Compared with the sham-operated group， total antioxidant capacity， SOD activity， and GSH levels were significantly decreased， while MDA levels were significantly increased in the model group （P<0.01）. Compared with the model group， total antioxidant capacity and antioxidant levels （SOD， GSH） increased significantly， and MDA decreased significantly in the medium- and high-dose DBT groups （P<0.01）， while no significant changes were observed in the low-dose DBT group. Compared with the sham-operated group， mRNA expression of p22^phox and p47^phox was significantly increased in the model group （P<0.01）. Compared with the model group， expression of p22^phox and p47^phox was significantly decreased in the DBT groups （P<0.05， P<0.01）. ConclusionDBT may exert neuroprotective effects by regulating PINK1/Parkin-mediated mitochondrial autophagy， thereby improving learning and memory abilities and treating VAD.

Objective: To explore the relationship between social jetlag and depressive symptoms in junior high school students, as well as the potential gender differences, so as to provide a reference for developing effective interventions for depressive symptoms and promoting adolescents mental health. Methods: In October 2024, a total of 3 516 students from grades 7 to 9 were recruited from 4 junior high schools in Chongqing Municipality using a combination of cluster sampling and convenience sampling. A questionnaire survey was conducted using the Center for Epidemiologic Studies Depression Scale (CES-D) and the Munich Chronotype Questionnaire (MCTQ). Statistical analyses included the χ 2 test, binary Logistic regression analysis, and stratified Logistic regression analysis. Results: The detection rate of depressive symptoms among the junior high school students was 34.3%. The number of students with social jetlag >2 h was 714 (20.3%), >1-2 h was 1 455(41.4%), and ≤1 h was 1 347(38.3%). Results from the binary Logistic regression analysis showed that compared to the group with social jetlag ≤1 h, the risk of depressive symptoms in the group with social jetlag >2 h was higher ( OR=1.59, 95%CI=1.28-1.98, P <0.01). Gender stratified analysis revealed that among females, the risk of depressive symptoms was higher in the groups with social jetlag of >1-2 h and >2 h compared to the ≤1 h group ( OR = 1.34 and 2.05, 95% CI =1.03-1.75 and 1.48-2.83, both P <0.05). However, among males, the associations were not statistically significant ( OR =1.11 and 1.29, 95% CI =0.86-1.43 and 0.95-1.77, both P >0.05). Conclusions Social jetlag is positively associated with depressive symptoms in junior high school students, demonstrating a threshold effect and gender differences. The findings suggest that reducing social jetlag may decrease the risk of depressive symptoms in adolescents, and targeted intervention measures should be developed considering different gender characteristics.

Objective To investigate the protective effect and underlying mechanism of human umbilical cord mesenchymal stem cell-derived exosomes (hucMSC-Exo) on renal ischemia-reperfusion injury (IRI). Methods hucMSC-Exos were isolated and characterized. A mouse renal IRI model was established and the animals were divided into Sham, IRI, IRI+hucMSC-Exo, IRI+hucMSC-Exo+JY-2 and Sham+JY-2 groups. Serum creatinine (Scr) and blood urea nitrogen (BUN) were measured. Hematoxylin-eosin (HE) staining was used to evaluate renal histopathology. Enzyme-linked immune absorbent assay was performed to determine serum interleukin (IL)-1β and IL-18 levels. Western blotting was used to detect the expression of activating transcription factor 3 (ATF3), Toll-like receptor 4 (TLR4), nuclear factor (NF)-κB, NOD-like receptor protein 3 (NLRP3), cysteineyl aspartate specific proteinase (Caspase)-1 p20 and Gasdermin D(GSDMD). Real-time fluorescent quantitative polymerase chain reaction was employed to measure ATF3, TLR4 and NF-κB messenger RNA (mRNA). Immunohistochemistry was conducted to examine NLRP3, Caspase-1 p20 and GSDMD. An in vitro hypoxia/reoxygenation (H/R) model was established in HK-2 cells and divided into Control, H/R, H/R+hucMSC-Exo, H/R+hucMSC-Exo+JY-2 and Control+JY-2 groups. Western blotting was used to detect the expression of ATF3, TLR4 and NF-κB. Real-time fluorescent quantitative polymerase chain reaction was used to measure NLRP3, GSDMD and Caspase-1 mRNA. Results HucMSC-Exos were successfully isolated and identified. Compared with the Sham group, the IRI group exhibited elevated Scr and BUN, higher tubular injury scores, increased protein expression levels of ATF3, TLR4, NF-κB p65, NLRP3, Caspase-1 p20 and GSDMD, and raised mRNA expression levels of ATF3, TLR4, NF-κB. Compared with the IRI group, the IRI+hucMSC-Exo group showed decreased Scr and BUN, lower tubular injury scores, up-regulated ATF3 protein and mRNA, down-regulated TLR4, NF-κB p65, NLRP3, Caspase-1 p20 and GSDMD protein, and declined TLR4 and NF-κB mRNA. Compared with the IRI+hucMSC-Exo group, the IRI+hucMSC-Exo+JY-2 group exhibited increased Scr and BUN levels, elevated renal tubular injury scores, decreased ATF3 protein expression levels, elevated protein expression levels of TLR4, NF-κB p65, NLRP3, Caspase-1 p20, and GSDMD, decreased ATF3 mRNA expression levels, and elevated mRNA expression levels of TLR4 and NF-κB. (all P < 0.05). Compared with the Control group, the expression levels of ATF3, TLR4 and NF-κB p65 proteins were increased in the H/R group, and the expression levels of NLRP3, Caspase-1 and GSDMD mRNA were increased. Compared with the H/R group, the expression level of ATF3 protein was increased, the expression levels of TLR4 and NF-κB p65 proteins were decreased, and the expression levels of NLRP3, Caspase-1 and GSDMD mRNA were decreased in the H/R+hucMSC-Exo group. Compared with the H/R+hucMSC-Exo group, the expression level of ATF3 protein was decreased, the expression levels of TLR4 and NF-κB p65 proteins were increased, and the expression levels of NLRP3, Caspase-1 and GSDMD mRNA were increased in the H/R+hucMSC-Exo+JY-2 group (all P < 0.05). Conclusions HucMSC-Exos alleviate renal IRI by up-regulating ATF3, thereby negatively regulating the TLR4/NF-κB signaling pathway and subsequently inhibiting pyroptosis.

ObjectiveTo explore the possible mechanisms by which ligustilide （LIG） exerts neuroprotective effects on ischemic stroke （IS） by inhibiting the release of neutrophil extracellular traps （NETs）， promoting blood-brain barrier repair， and alleviating post-ischemic neuroinflammation， thereby providing a new direction for IS treatment. MethodsA middle cerebral artery occlusion （MCAO） model was established in rats. The rats were divided into the sham operation （Sham） group， model （Model） group， low- and high-dose LIG groups （20， 40 mg·kg^-1）， and the NET inhibitor CI-amidine group （CI-amidine， 10 mg·kg^-1）. Drug treatments were administered for 3 days. Neurological injury after ischemia was evaluated by 2，3，5-triphenyltetrazolium chloride （TTC） staining， neurological deficit scoring， and brain index measurement. Flow cytometry and Western blot were used to analyze changes in neutrophil expression. Immunofluorescence was used to observe the fluorescence intensity of the NET marker citrullinated histone H3 （H3Cit）. Western blot was performed to detect the expression of blood-brain barrier tight junction-related proteins and inflammatory factors， including interleukin-18 （IL-18） and interleukin-1β （IL-1β）. ResultsCompared with the Sham group， the Model group exhibited significant brain tissue injury （P<0.05）， significantly increased neutrophil numbers and NET expression （P<0.05）， significantly impaired blood-brain barrier permeability （P<0.05）， and significantly increased expression of inflammatory factors （P<0.05）. Compared with the Model group， both low- and high-dose LIG significantly alleviated brain tissue injury in rats （P<0.01）， inhibited neutrophil numbers and NET expression （P<0.01）， reduced blood-brain barrier damage （P<0.01）， and suppressed the expression of inflammatory factors IL-18 and IL-1β （P<0.01）， thereby ultimately exerting a neuroprotective effect. ConclusionThe neuroprotective effect of LIG in rats with cerebral ischemia-reperfusion injury may be related to inhibition of neutrophils and the NETs induced by them.

Background Lung cancer, one of the most common malignant tumors worldwide, has long ranked first in cancer incidence and mortality, posing a severe challenge to public health systems. Objective To analyze the trends in incidence, mortality, and disability-adjusted life years (DALYs) of lung cancer among residents in Jing'an District, Shanghai, from 2002 to 2021, explore the impacts of population aging, population growth, and age-specific prevalence on disease burden, and provide a scientific basis for optimizing regional lung cancer prevention and control strategies. Methods Based on the cancer registration and cause-of-death surveillance data of registered residents in Jing'an District, Shanghai, from 2002 to 2021, Joinpoint regression models were used to analyze the annual change trends (APC) and average annual change trends (AAPC) of lung cancer incidence, mortality, DALY rate, and their age-standardized rates. Decomposition analysis was applied to quantify the contribution of population aging, population growth, and age-specific prevalence to changes in the number of new cases, deaths, and DALYs. Results From 2002 to 2021, the crude incidence rate of lung cancer in Jing'an District increased from 68.00 per 100000 to 144.36 per 100000 (AAPC=4.86%, P<0.001), and the age-standardized incidence rate rose from 43.09 per 100000 to 61.46 per 100000 (AAPC=2.89%, P<0.001). The growth rate of incidence was significantly higher in females (AAPC=6.73%) than in males (AAPC=3.62%). The crude mortality rate increased from 58.08 per 100000 to 66.11 per 100000 (AAPC=1.10%, P<0.001), while the age-standardized mortality rate decreased (AAPC=−1.54%, P<0.001). The crude DALY rate showed an upward trend (AAPC=0.94%, P=0.002), whereas the age-standardized DALY rate declined (AAPC=−1.63%, P<0.001). Significant differences were observed across genders and age groups: the mortality and DALY rates increased in males aged 60-64 years, while the fastest incidence growth occurred in females aged 45-64 years. The results of decomposition analysis indicated that the increase in new cases was primarily attributed to age-specific incidence (38.15%) and aging (37.31%); the growth in deaths and DALYs was driven by aging, while age-specific mortality and population growth showed offsetting effects. From 2002 to 2021, the probability of premature death from lung cancer among males (2.04%-2.52%) in Jing'an District showed no statistically significant trend (AAPC=−0.28%, P=0.440), while it presented a decreasing trend in the total population (1.37%-1.89%) and females (0.72%-1.26%) (AAPC=−0.80% and −2.23%, respectively; P=0.029 and <0.001, respectively). Conclusion From 2002 to 2021, the risk of lung cancer incidence in Jing’an District, Shanghai, continue to increase, with a disease burden exhibiting significant heterogeneity by gender and age: key features include a rapid increase in new cases and a trend toward younger onset among females, alongside rising mortality risk among males aged 60–64 years. Population aging and increasing age-specific incidence rates are primary drivers of the growing number of cases, while declining age-specific mortality rates mitigate the rise in mortality burden.

ObjectiveTo explore the possible mechanisms by which ligustilide （LIG） exerts neuroprotective effects on ischemic stroke （IS） by inhibiting the release of neutrophil extracellular traps （NETs）， promoting blood-brain barrier repair， and alleviating post-ischemic neuroinflammation， thereby providing a new direction for IS treatment. MethodsA middle cerebral artery occlusion （MCAO） model was established in rats. The rats were divided into the sham operation （Sham） group， model （Model） group， low- and high-dose LIG groups （20， 40 mg·kg^-1）， and the NET inhibitor CI-amidine group （CI-amidine， 10 mg·kg^-1）. Drug treatments were administered for 3 days. Neurological injury after ischemia was evaluated by 2，3，5-triphenyltetrazolium chloride （TTC） staining， neurological deficit scoring， and brain index measurement. Flow cytometry and Western blot were used to analyze changes in neutrophil expression. Immunofluorescence was used to observe the fluorescence intensity of the NET marker citrullinated histone H3 （H3Cit）. Western blot was performed to detect the expression of blood-brain barrier tight junction-related proteins and inflammatory factors， including interleukin-18 （IL-18） and interleukin-1β （IL-1β）. ResultsCompared with the Sham group， the Model group exhibited significant brain tissue injury （P<0.05）， significantly increased neutrophil numbers and NET expression （P<0.05）， significantly impaired blood-brain barrier permeability （P<0.05）， and significantly increased expression of inflammatory factors （P<0.05）. Compared with the Model group， both low- and high-dose LIG significantly alleviated brain tissue injury in rats （P<0.01）， inhibited neutrophil numbers and NET expression （P<0.01）， reduced blood-brain barrier damage （P<0.01）， and suppressed the expression of inflammatory factors IL-18 and IL-1β （P<0.01）， thereby ultimately exerting a neuroprotective effect. ConclusionThe neuroprotective effect of LIG in rats with cerebral ischemia-reperfusion injury may be related to inhibition of neutrophils and the NETs induced by them.

ObjectiveTo investigate the intervention mechanism of the traditional Chinese medicine Number 2 Feibi recipe （N2FBR） in idiopathic pulmonary fibrosis （IPF）， focusing on its effects on endoplasmic reticulum （ER） stress， apoptosis， stemness maintenance， and regenerative capacity of alveolar type Ⅱ epithelial cells （AT2 cells）， and to validate the modern translational pathway of the theory of "deficiency of Zong Qi leading to pulmonary atelectasis and atrophy". MethodsA mouse model of pulmonary fibrosis was induced by bleomycin （BLM）. Mice were randomly divided into blank control， model， low-， and high-dose N2FBR intervention groups （9.1， 18.2 g·kg^-1）， and prednisolone intervention group （6.5 mg·kg^-1）. Pulmonary histopathological changes and collagen deposition were evaluated using hematoxylin-eosin （HE） and Masson's trichrome staining. Hydroxyproline （HYP） content was measured by the alkaline hydrolysis method. Lung coefficient and pulmonary function parameters were evaluated. The mRNA expression levels of fibrosis-related factors， including collagen type Ⅰ alpha 1 chain （ColIa1）， alpha-smooth muscle actin （α-SMA）， and tissue inhibitor of metalloproteinase 1 （Timp1）， were detected by real-time polymerase chain reaction （Real-time PCR）. Cell apoptosis was assessed using the terminal deoxynucleotidyl transferase dUTP nick-end labeling （TUNEL） assay. Apoptosis of AT2 cells was further evaluated by double immunofluorescence staining for surfactant protein C （SPC） and cysteine-aspartic protease-3 （Caspase-3）. Endoplasmic reticulum （ER） stress in AT2 cells was examined by double staining for SPC and protein kinase R-like endoplasmic reticulum kinase （PERK）. Ultrastructural changes of ER and lamellar bodies in AT2 cells were observed by transmission electron microscopy （TEM）. The expression levels of key proteins involved in ER stress and apoptosis pathways， including PERK， activating transcription factor 4 （ATF4）， and Caspase-3， were detected by Western blot. Double immunofluorescence staining of SPC and Ki-67 antigen （Ki-67） was performed to evaluate the proliferative capacity of AT2 cells. Lineage tracing technology （labeling AT2 cells with GFP） combined with Krt8 labeling was used to evaluate intermediate differentiation states， and morphological transformation of AT2 cells into alveolar type Ⅰ epithelial cells （AT1） was observed. ResultsBLM-induced mice exhibited significant structural disruption of lung tissue， increased collagen deposition， elevated lung coefficient， decreased pulmonary function， and upregulation of fibrosis-related factors （P<0.01）. High-dose N2FBR treatment significantly ameliorated lung tissue damage and dysfunction， significantly reduced HYP content （P<0.01）， and significantly downregulated ColIa1， α-SMA， and Timp1 expression （P<0.01）. Apoptosis analysis showed increased TUNEL-positive and Caspase-3-positive AT2 cells in the model group， which was significantly reduced by high-dose N2FBR treatment. TEM revealed swollen ER structures in AT2 cells of the model group， which tended to return to normal following treatment. PERK protein staining analysis showed evident ER stress in AT2 cells of the model group， which were markedly alleviated in the treatment group. The expression levels of ER stress-related proteins PERK and ATF4， as well as the apoptosis-related protein Caspase-3， were elevated in the model group and significantly reduced after treatment. TEM also revealed disrupted lamellar body structures in the model group， which tended to recover in the treatment group. Regarding the proliferative capacity of AT2 cells， the proportion of Ki-67⁺SPC⁺ AT2 cells significantly increased in the treatment group （P<0.01）. Lineage tracing showed that the proportion of keratin 8-positive green fluorescent protein-positive （Krt8⁺GFP⁺） cells increased in the model group， indicating differentiation arrest. This proportion was significantly reduced in the treatment group， and the morphology of GFP⁺ cells exhibited a flattened， extended shape， suggesting restored differentiation toward AT1 cells. ConclusionN2FBR alleviates ER stress in AT2 cells， reduces AT2 cell apoptosis， restores lamellar body structure and function， enhances proliferation activity， and alleviates differentiation arrest to promote differentiation into AT1 cells， thereby repairing the alveolar epithelium and effectively blocking the progression of pulmonary fibrosis. Its traditional Chinese medicine mechanism of "replenishing Zong Qi， harmonizing Qi and blood， and unblocking pulmonary meridians" closely aligns with the modern regulatory pathway of AT2 stem cells， providing a novel theoretical basis and experimental evidence for the intervention of IPF with traditional Chinese medicine.

ObjectiveTo investigate the intervention mechanism of the traditional Chinese medicine Number 2 Feibi recipe （N2FBR） in idiopathic pulmonary fibrosis （IPF）， focusing on its effects on endoplasmic reticulum （ER） stress， apoptosis， stemness maintenance， and regenerative capacity of alveolar type Ⅱ epithelial cells （AT2 cells）， and to validate the modern translational pathway of the theory of "deficiency of Zong Qi leading to pulmonary atelectasis and atrophy". MethodsA mouse model of pulmonary fibrosis was induced by bleomycin （BLM）. Mice were randomly divided into blank control， model， low-， and high-dose N2FBR intervention groups （9.1， 18.2 g·kg^-1）， and prednisolone intervention group （6.5 mg·kg^-1）. Pulmonary histopathological changes and collagen deposition were evaluated using hematoxylin-eosin （HE） and Masson's trichrome staining. Hydroxyproline （HYP） content was measured by the alkaline hydrolysis method. Lung coefficient and pulmonary function parameters were evaluated. The mRNA expression levels of fibrosis-related factors， including collagen type Ⅰ alpha 1 chain （ColIa1）， alpha-smooth muscle actin （α-SMA）， and tissue inhibitor of metalloproteinase 1 （Timp1）， were detected by real-time polymerase chain reaction （Real-time PCR）. Cell apoptosis was assessed using the terminal deoxynucleotidyl transferase dUTP nick-end labeling （TUNEL） assay. Apoptosis of AT2 cells was further evaluated by double immunofluorescence staining for surfactant protein C （SPC） and cysteine-aspartic protease-3 （Caspase-3）. Endoplasmic reticulum （ER） stress in AT2 cells was examined by double staining for SPC and protein kinase R-like endoplasmic reticulum kinase （PERK）. Ultrastructural changes of ER and lamellar bodies in AT2 cells were observed by transmission electron microscopy （TEM）. The expression levels of key proteins involved in ER stress and apoptosis pathways， including PERK， activating transcription factor 4 （ATF4）， and Caspase-3， were detected by Western blot. Double immunofluorescence staining of SPC and Ki-67 antigen （Ki-67） was performed to evaluate the proliferative capacity of AT2 cells. Lineage tracing technology （labeling AT2 cells with GFP） combined with Krt8 labeling was used to evaluate intermediate differentiation states， and morphological transformation of AT2 cells into alveolar type Ⅰ epithelial cells （AT1） was observed. ResultsBLM-induced mice exhibited significant structural disruption of lung tissue， increased collagen deposition， elevated lung coefficient， decreased pulmonary function， and upregulation of fibrosis-related factors （P<0.01）. High-dose N2FBR treatment significantly ameliorated lung tissue damage and dysfunction， significantly reduced HYP content （P<0.01）， and significantly downregulated ColIa1， α-SMA， and Timp1 expression （P<0.01）. Apoptosis analysis showed increased TUNEL-positive and Caspase-3-positive AT2 cells in the model group， which was significantly reduced by high-dose N2FBR treatment. TEM revealed swollen ER structures in AT2 cells of the model group， which tended to return to normal following treatment. PERK protein staining analysis showed evident ER stress in AT2 cells of the model group， which were markedly alleviated in the treatment group. The expression levels of ER stress-related proteins PERK and ATF4， as well as the apoptosis-related protein Caspase-3， were elevated in the model group and significantly reduced after treatment. TEM also revealed disrupted lamellar body structures in the model group， which tended to recover in the treatment group. Regarding the proliferative capacity of AT2 cells， the proportion of Ki-67⁺SPC⁺ AT2 cells significantly increased in the treatment group （P<0.01）. Lineage tracing showed that the proportion of keratin 8-positive green fluorescent protein-positive （Krt8⁺GFP⁺） cells increased in the model group， indicating differentiation arrest. This proportion was significantly reduced in the treatment group， and the morphology of GFP⁺ cells exhibited a flattened， extended shape， suggesting restored differentiation toward AT1 cells. ConclusionN2FBR alleviates ER stress in AT2 cells， reduces AT2 cell apoptosis， restores lamellar body structure and function， enhances proliferation activity， and alleviates differentiation arrest to promote differentiation into AT1 cells， thereby repairing the alveolar epithelium and effectively blocking the progression of pulmonary fibrosis. Its traditional Chinese medicine mechanism of "replenishing Zong Qi， harmonizing Qi and blood， and unblocking pulmonary meridians" closely aligns with the modern regulatory pathway of AT2 stem cells， providing a novel theoretical basis and experimental evidence for the intervention of IPF with traditional Chinese medicine.

Abstract To further differentiate the differentiated effects of emotional responses to social media among adolescents, the study systematically reviews the main current methods for measuring social media emotional responses. It elaborates on the impacts of adolescents emotional responses to social media on their physical health, mental health, and social adaptation, as well as the multiple pathways and potential mechanisms through which adverse health effects are induced. It also highlights the current lack of empirical support for biological mechanisms in existing research, and provides a reference for future in depth exploration of biological mechanisms and the development of effective intervention strategies.