OBJECTIVE  To investigate the analgesic effects and potential mechanisms of the partial agonist of the 5-hydroxytryptamine 1A (5-HT_1A) receptor and the selective 5-HT reuptake inhibitor, viladazone (Vil), in various animal models of pain. METHODS  ① Mouse acetic acid writhing test: KM mice were divided into the model group, model+morphine 10 mg·kg^-1 group, and model+Vil 2, 4, 8 mg·kg^-1 groups. Thirty minutes after ig administration of saline (model group) or corresponding drugs, each group was ip injected with a 2% acetic acid aqueous solution (0.01 mL·g^-1), and the writhing frequency of the mice was observed and recorded from 5 to 20 min. ② Mouse formalin pain test: KM mice were divided into the model group and model+Vil 2, 4 and 8 mg·kg^-1 groups. Thirty minutes after ig administration of saline (model group) or drugs, 20 μL of 5% formalin solution was sc injected into the right plantar region of the mice. The licking time (the sum of the duration of licking and biting the paw) of the mice was observed and recorded during two periods: the acute phase (0-5 min after sc formalin injection) and the delayed phase (15-35 min after sc formalin injection). ③ Rat chronic constriction injury (CCI) of the sciatic nerve experiment: SD rats successfully examined with a paw withdrawal threshold (PWT) <5 g were randomly divided into a CCI model group and a CCI model+Vil 2, 4 and 8 mg·kg^-1 group. Solvent (model group) or corresponding drugs were ig administered, and the PWT of the modeled side was measured at 30, 60, 120 and 240 min after the first administration to evaluate the acute analgesic effect of Vil on mechanical pain. Then, Vil was continuously ig administered for 14 d, and the PWT was measured 1 h after Vil administration on the 7^th and 14^th d to evaluate the long-term analgesic effect of Vil. Immunofluorescence staining was employed to analyze the expression levels of inflammation-related proteins, ionized calcium binding adapter molecule 1 (IBA-1), tumor necrosis factor α (TNF-α), and interleukin 1β (IL-1β), in brain tissues. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of IBA-1, TNF-α and IL-1β in the dorsal root ganglion of the spinal cord in the CCI model. RESULTS  ① In the mouse model of acetic acid writhing, single ig administration of morphine 10 mg·kg-1 and Vil at varied doses significantly reduced the number of writhings induced by acetic acid compared to the model group. ② In the formalin-induced pain model, the average licking time of the model group was 50.5 s during the acute phase of inflammatory pain (0-5 min after intraplantar injection of 5% formalin), and 347.9 s during the delayed phase of inflammatory pain (25-35 min after formalin injection). Compared to the model group, single ig administration of Vil 2-8 mg·kg^-1 reduced chronic pain induced by formalin in mice, and each dose of Vil significantly decreased the licking time of mice, but had no notable impact on the licking duration exhibited by mice during acute phase. ③ In the CCI model, the PWT values of CCI model rats significantly decreased compared with the control group. Pathological damage to varying extents was observed in brain slices, manifested as enlarged intercellular spaces and the appearance of vacuoles. The expression of IBA-1 in brain tissue significantly increased, while TNF-α and IL-1β hardly changed. The levels of IBA-1, TNF-α and IL-1β in the spinal dorsal root ganglion significantly increased. Compared with the CCI model, after single administration of Vil 2-8 mg·kg^-1 for 60, 120 and 240 min, Vil significantly reduced the PWT values. After two-week continuous administration, the PWT values in Vil 4 and 8 mg·kg^-1 were significantly reduced, and Vil 2-8 mg·kg^-1 could alleviate the neuropathic pain to some extent. Vil 8 mg·kg^-1 significantly reduced the elevated levels of inflammatory factors compared to CCI rats. CONCLUSION  The antidepressant Vil exhibits analgesic effects in mouse models of acetic acid writhing, formalin-induced inflammation, and neuropathic pain induced by CCI in rats, with a more pronounced effect on neuropathic pain. The mechanism of action may be related to the inhibition of inflammatory pathways of IBA-1.

OBJECTIVE  To investigate the impact of cerebral ischemia-reperfusion (CIR) injury on  glucuronidation of IMM-H004 in the brain. METHODS  IMM-H004, a neuroprotective agent, underwent glucuronidation primarily mediated by uridine diphosphate glucuronosyltransferases (UGT) to form IMM-H004G, which was subsequently hydrolyzed back to IMM-H004 by β-glucuronidase. ① Cellular experiments: human glial cells (HEB) and human neuroblastoma cells (SH-SY5Y) cell lines were assigned to two groups: a normal control group and an oxygen-glucose deprivation/reoxygenation (OGD/R) model group. An OGD/R model was established by subjecting the cells to one-hour oxygen-glucose deprivation, followed by reoxygenation. Cell viability was assessed using the methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. The mRNA levels of UGT and its regulatory factor, nuclear factor erythroid 2 related factor 2 (Nrf2 ), were measured by real-time fluorescence quantitative PCR (RT-qPCR). The content of IMM-H004G glucuronidated from IMM-H004, and the content of IMM-H004 hydrolyzed from IMM-H004G were determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). ② Animal experiments: Male SD rats were randomly assigned to three groups: a normal control group, a CIR model group, and a sham operation group. Rats in the normal control group received no surgical interventions while those in the CIR model group underwent four-vessel occlusion surgery to induce acute CIR injury. Rats in the sham operation group was treated the same way as the CIR model group except for the four-vessel occlusion. The activities of UGT and β-glucuronidase in brain tissues were determined by LC-MS/MS. IMM-H004 was administered via intracerebroventricular injection, and the concentrations of IMM-H004 and IMM-H004G in different regions of the brain were determined using LC-MS/MS to investigate the impact of CIR injury on IMM-H004 metabolism. RESULTS  ① Cellular experiments: Compared with the control group, OGD/R injury reduced the viability of HEB and SH-SY5Y cells to 72.30% and 53.56%, respectively. In HEB cells, OGD/R injury significantly downregulated the mRNA expressions of UGT1A1, UGT1A7 and UGT1A8, resulting in a reduction of IMM-H004G production to 50.05%-68.95% of the normal level, while hydrolytic metabolism remained unaffected. No significant changes were observed in SH‐SY5Y cells. ② Animal experiments: CIR injury had no impact on the activity of UGT or β-glucuronidase in rat brain tissues. In addition, the distribution of IMM-H004 and IMM-H004G across different brain regions remained unchanged. CONCLUSION  These findings show that OGD/R injury reduces UGT-mediated glucuronidation of IMM-H004, whereas CIR injury does not significantly affect its metabolism in the brain, suggesting the presence of compensatory mechanisms in brain tissues that help maintain drug homeostasis.

OBJECTIVE  To establish a preparation system for megakaryocytes (MKs) derived from human embryonic stem cells (hESCs) and MK microparticles (MKMPs), and to assess the pro-angiogenic efficiency of these microparticles. METHODS  ① hESCs were induced to mesodermal progenitor cells via monolayer culture with the first-stage induction medium for 2 days before the cells were induced to hemogenic endothelial/hematopoietic progenitor cells by culturing with the second-stage 
induction medium for another 3 days. Then, the cells were dissociated into single cells, seeded into the third-stage induction medium, and cultured using the suspension method for 8 days to obtain MKs. The specific characters of differentiated cells were identified through morphological observation and flow cytometry before stage-specific marker proteins in different periods were analyzed [hESCs: TRA-1-60, sialyl glycolipid stage-specific embryonic antigen4 (SSEA4)];mesodermal progenitor cells: brachyury; hemogenic endothelial/hematopoietic progenitor cells: CD34, CD43; MKs:CD41a, CD42b), and immunofluorescence staining [β1-tubulin, von Willebrand factor (VWF)], [friend leukemia integration 1 (FLI1), CD42]. ② MKMP collection and verification: MKMPs were collected via differential centrifugation. The concentration and size of these MKMPs were determined by nanoparticle tracking analysis (NTA), and both the morphology and ultrastructure were examined by transmission electron microscopy (TEM). Besides, the MKMPs-specific proteins [CD41, tumor susceptibility gene 101 (TSG101) and CD9] were detected by Western blotting analysis. ③ Biological function of MKMPs: MKMPs were stained with CD41a-PE antibodies and co-cultured with human umbilical veinvascular endothelial cells (HUVECs) labeled by CD34-APC for 3 h. Live-cell immunofluorescence was employed to find out whether HUVECs could absorb MKMPs. To find out whether MKMPs could affect the role of HUVECs in angiogenesis and cell migration, platelet microvesicles (PMPs) were used as positive controls. The experimental groups were added with different concentrations of microparticles (1, 5, 10 and 20 mg·L-1) while the control group was given no microparticles (0 mg·L^-1). The number of nodes that formed the lumen after 5 h of incubation in Matrigel was counted, and the size of healing of the scratch area was analyzed after 6 h. To elucidate the mechanism through which MKMPs impacted angiogenesis, ELISA was used out to quantitatively detect the concentration of proteins in microparticles. RESULTS  ① A three-stage differentiation cultural system was established to develop hESCs into MKs. Flow cytometry revealed progressive loss of pluripotency markers SSEA4 and TRA-1-60, while the mesodermal 
progenitor marker brachyury peaked at d 2. Subsequently, hemogenic endothelial/hematopoietic progenitor markers CD34 and CD43 emerged at d 5, followed by megakaryocytic markers CD41a and CD42b at d 13. Immunofluorescent images further demonstrated that MKs expressed specific proteins CD42, β1-tubulin, von VWF and FLI1 at d 13. ② Microparticles were collected via differential centrifugation. Transmission electron microscopy revealed that their substructure exhibited a typical double-layered membrane. Nanoparticle tracking analysis indicated that the size was (164.3±14.0) nm. The result of WB demonstrated that the microparticles expressed specific markers, including TSG101, CD9 and CD41. ③ MKMPs were absorbed after being co-cultured with HUVECs for 3 h and enhanced the ability of HUVECs to form tubes and migrate. Notably, the treatment of 5 mg·L-1 MKMPs was more effective than 5 mg·L-1 PMPs treatment. The results of ELISA showed that the content of VEGF from MKMPs was higher than from PMPs, which may be the key factor in regulating endothelial biological function. CONCLUSION  MKs derived from hESCs can generate functional microparticles which can promote angiogenesis.

OBJECTIVE  To study how resveratrol (Res) mitigates acute lung injury (ALI) in mice induced by sulfur mustard (SM) and potential mechanism. METHODS  Male C57BL/6N mice were randomly divided into the control group (50 μL physiological saline via nebulization), SM group (SM 5 mg·kg^-1 via nebulization), SM+Res 10 or 20 mg·kg^-1 groups (1 h after administration of SM 5 mg·kg^-1, Res 10 or 20 mg·kg^-1 was administered via nebulization). Mice in each group were weighed 0, 24, 48 and 72 h after SM administration. Mice were sacrificed 72 h after SM administration, and lung tissues were 
collected, weighed for wet and dry weights, and the wet/dry ratio  was calculated. HE staining was employed to detect the pathological changes of lung tissues while real-time quantitative PCR (RT-qPCR) was used to detect the mRNA expression levels of interleukin 6 (IL-6) and IL-1β. Transcriptomic changes of the SM group and the SM+Res 20 mg·kg^-1 group were detected with the next-generation sequencing technology. RT-qPCR was used to detect the mRNA expression changes of adenosine 5′-monophosphate-activated protein kinase (AMPK) and silence information regulator 1 (SIRT1) in lung tissues. 
RESULTS  72 h after SM administration, the body mass of mice in the SM group was significantly decreased compared with normal control group, while the wet/dry ratio of the lung was significantly increased, so were the mRNA expression levels of IL-6 and IL-1β in lung tissues were also significantly increased. Pathological changes of lung tissues included alveolar cavity atrophy, marked parenchymal tissues, and diffuse infiltration of local inflammatory cells. Compared with the SM group, the body mass of mice in the SM+Res 10 and 20 mg·kg^-1 groups significantly increased, the wet/dry ratio of lung tissues was significantly reduced, and expressions of IL-6 and IL-1β mRNA were significantly decreased in SM+Res 10 and 20 mg·kg^-1 groups. Compared with the normal control group, the mRNA expression levels of AMPK and SIRT1 in lung tissues of the SM group were significantly decreased. Compared with the SM group, the mRNA expression levels of AMPK in lung tissues of the SM+Res 10 and 20 mg·kg-1 groups were significantly increased while the mRNA expression level of SIRT1 was significantly decreased. CONCLUSION  Res can mitigate ALI in mice induced by SM, and the mechanism may be related to the inhibition of cell apoptosis by regulating the AMPK/SIRT1 signaling pathway.

OBJECTIVE  To investigate the effect of salvianolic acid A (SAA) on functions of neutrophils after activation in vitro. METHODS  Rat neutrophils were extracted and activated by lipopolysaccharide (LPS) at 0.3, 1, 3 mg·L^-1, and the number of adherent neutrophils and myeloperoxidase (MPO) activity were detected to determine the concentration of LPS. Neutrophils were divided into the control, model, model+4-aminobenzohydrazide (ABH) 20 μmol·L^-1, and model+SAA 1, 3 and 10 μmol·L^-1 groups. LPS was stimulated with 3 mg·L^-1 for 30 min, and the neutrophil adhesion rate was detected by immunofluorescence after 1 h of drug incubation. After 2 h of drug incubation, phagocytosis of neutrophils was detected by immunofluorescence and fluorescein isothiocyanate-immunoglobulin G. After 3 h of drug incubation, the neutrophil adhesion rate to endothelial cells was detected by colorimetric assay. Intracellular MPO activity and hypochlorous acid (HOCl) production were investigated by colorimetric assay in response to the degranulation function. Intracellular reactive oxygen species (ROS) levels were detected by probe assay, and mitochondrial membrane potential by JC-1 assay. The levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH) and total antioxidant capacity (T-AOC) were measured to reflect oxidation function of neutrophils. RESULTS  LPS increased the number of adherent cells and MPO activity in a concentration-dependent manner, with 3 mg·L-1 of LPS showing the most significant effect, which was used for subsequent experiments. Compared with the control group, LPS-activated neutrophil adhesion and phagocytosis were significantly enhanced. MPO activity and HOCl production significantly increased. The levels of ROS and MDA in LPS-activated neutrophils were significantly increased while the mitochondrial membrane potential and the levels of SOD, GSH, T-AOC were significantly decreased, indicating that the oxidative stress ability was enhanced. Compared with the model group, SAA dose-dependently inhibited LPS-induced adhesion, phagocytosis, degranulation, and ROS generation of neutrophils, with significant effects at medium and high doses. CONCLUSION  SAA can inhibit different functions of neutrophils after activation, which may be a potential drug for targeting neutrophil function regulation.

Breast cancer is a highly prevalent malignant tumor among women worldwide, and its clinical treatment faces significant challenges, such as high postoperative recurrence rates, high metastasis rates, and therapeutic resistance. Studies indicate that monocyte-derived immune cells play a critical role in promoting breast cancer progression by establishing an immunosuppressive tumor microenvironment and pre-metastatic niche. Monocytic myeloid-derived suppressor cells, tumor-associated macrophages, and monocyte-derived dendritic cells secrete various cytokines, including interleukins, colony-stimulating factors, tumor necrosis factor, chemokines C-C motif chemokine ligand/C-X-C motif chemokine ligand (CCL/CXCL), and growth factors, which activate multiple signaling pathways and promote the development of breast cancer and its metastasis to such organs as bones, lungs, brains and livers through mechanisms involving CCL/CXCL-mediated recruitment, angiogenesis induction, and immune evasion. Therefore, targeting the regulation of monocyte-derived immune cells and their secreted cytokines may become a crucial therapeutic approach to breast cancer. This review summarizes the mechanisms by which monocyte-derived immune cells and their cytokines contribute to the development and metastasis of breast cancer by exploring. It further explores therapeutic strategies targeting these cells and cytokines, such as modulating phenotypic transformation, reprogramming cellular metabolism, and regulating cytokine expression levels.

Eosinophilic gastroenteritis (EG) is a rare disease characterized by abnormal infiltration of eosinophils (Eos) in gastrointestinal tissues. Due to the unclear pathogenesis of EG and the lack of effective therapeutic drugs, research on its novel mechanisms, targets and drugs is critical. This article starts by outlining the research progress in the pathogenesis of EG, involving IgE mediated typeⅠimmediate allergic reactions and T helper 2 cell (Th2) mediated delayed allergic reactions. Then, the related targets of EG are summarized, including Th2 cytokines and factors regulating Eos function, but there has been no breakthrough in the treatment of these targets. Finally, the therapeutic drugs for EG are reviewed, such as glucocorticoids, antiallergic drugs and biologics. The advantages and disadvantages of various drugs are also described. However, these drugs cannot meet the current demands of clinical treatment and there is an urgent need to develop novel therapeutic drugs. It is believed that multi-target therapy is an ideal treatment for EG, and that traditional Chinese medicine and natural products should be the priorities of research and development for EG therapeutic drugs in the future. This review is expected to provide new ideas for the clinical treatment strategies and drug development of EG.

The inflammatory response is a natural defense mechanism of the body that occurs in response to infection or injury, serving as a critical starting point for the onset and progression of various diseases. Glycolysis, an essential pathway for energy production within the body, plays a pivotal role in both the initiation and advancement of the inflammatory response. Pyruvate kinase M2 (PKM2), recognized as a key rate-limiting enzyme in glycolysis, not only contributes to the inflammatory process by mediating glycolysis and lactylation modifications through such mechanisms as nuclear translocation and dimer formation, but also regulates the inflammatory response by modulating immune responses in B cells, T cells, macrophages, and neutrophils. This review aims to summarize the mechanisms involved in targeting PKM2 to suppress inflammation, providing new insights into the prevention and treatment of inflammatory reactions.