Objective:To elucidate the molecular mechanisms through which high-dose dexamethasone exerts long-term effects on bone marrow mesenchymal stem cells (BMSCs), specifically its role in suppressing osteogenic differentiation, accelerating cellular senescence, triggering the senescence-associated secretory phenotype (SASP), and inducing apoptosis.Methods:Primary rat BMSCs were isolated and treated with high-dose dexamethasone (1×10 -4 mol/L) to establish the experimental group, while untreated cells served as the control. The gene and protein expression levels of osteogenic markers, bone alkaline phosphatase (bALP) and Runt-related transcription factor 2 (Runx2), were analyzed in both groups. Cellular senescence was evaluated using senescence-associated β-galactosidase (SA-β-gal) staining. The expression of senescence-related markers (P16 and P21), components of the senescence-associated secretory phenotype (SASP), including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and interferon (IFN)-γ, as well as apoptosis-related proteins (Bcl-2, Bax, and Cleaved-Caspase-3), and key factors of the Nrf2/HO-1 signaling pathway were assessed at both transcriptional and protein levels using qRT-PCR, immunofluorescence, and Western-blot analyses. These comprehensive evaluations aimed to determine the senescent state, apoptotic features, and alterations in osteogenic differentiation of BMSCs. Results:Following treatment with dexamethasone and subsequent withdrawal, both qRT-PCR and Western blot analyses indicated a significant reduction in the expression of the osteogenic markers bALP and Runx2 at both mRNA and protein levels. The proportion of SA-β-gal positive cells was markedly higher in the dexamethasone group (74.33%±6.89%) than in the control group (20.30%±1.57%, t=17.300, P<0.001). qRT-PCR analysis revealed upregulated mRNA expression of the senescence-related genes P16 and P21 after dexamethasone treatment, which was further supported at the protein level by immunofluorescence showing increased P21 expression. Western-blot results confirmed that protein expression levels of P16 and P21 were significantly elevated in the dexamethasone group (7.025±0.255 and 6.362±0.456, respectively) compared with the control group (1.016±0.115 and 0.816±0.172; both P<0.05). Furthermore, gene expression levels of the senescence-associated secretory phenotype (SASP) factors TNF-α and IL-1β were significantly increased (TNF-α: 3.539±0.599 vs. 0.742±0.095; IL-1β: 4.469±0.331 vs. 0.799±0.175; both P<0.05), and their protein expression was consistently upregulated as validated by Western-blot. Additionally, protein expression levels of TNF-α, IL-1β, and IFN-γ were significantly higher in the dexamethasone-treated group (3.476±0.932 vs. 0.945±0.095; 4.111±0.220 vs. 0.762±0.105; 2.155±0.240 vs. 0.656±0.104; all P<0.05).Western-blot analysis also demonstrated that protein expression of Nrf2 and HO-1 was significantly suppressed in the dexamethasone group (0.21±0.07 and 0.19±0.06, respectively) compared with the control group (1.13±0.15 and 0.92±0.21; P<0.05). Moreover, Western-blot analysis revealed that the expression levels of the pro-apoptotic proteins Bax and Cleaved-Caspase-3 were significantly up, regulated in the dexamethasone, treated BMSCs (Bax: 3.673±0.397 vs. 0.453±0.111; Cleaved-Caspase-3: 3.863±0.399 vs. 0.465±0.057), while the expression of the anti-apoptotic protein Bcl-2 was markedly down, regulated (0.959±0.073 vs. 2.126±0.195), with all differences being statistically significant ( P<0.05). Conclusions:High-dose dexamethasone treatment of BMSCs, followed by withdrawal of dexamethasone, induces cellular senescence and enhances the expression of the senescence-associated secretory phenotype (SASP) through suppression of the Nrf2/HO-1 signaling pathway. Concurrently, it promotes apoptosis by activating the mitochondrial apoptotic pathway, collectively leading to impaired osteogenic differentiation of BMSCs.

Objective:To evaluate the efficacy of dexmedetomidine-scalp nerve block (SNB) combined with general anesthesia in the patients with acute traumatic brain injury (TBI) undergoing craniotomy.Methods:In this randomized controlled trial, 74 American Society of Anesthesiologists Physical Status classification Ⅰ-Ⅲ patients of either sex with acute TBI, aged 30-78 yr, with body mass index of 18-30 kg/m 2, underwent craniotomy for hematoma evacuation combined with decompressive craniectomy at the Traditional Chinese Medicine Hospital of Kunshan from January to December 2024, of the Glasgow Coma Scale score 8-12, were selected and divided into 2 groups ( n=37 each) using a random number table method: dexmedetomidine combined with ultrasound-guided SNB group (DS group) and ultrasound-guided SNB group (S group). Before anesthesia, dexmedetomidine was infused as a loading dose of 1 μg/kg over 10 min followed by an infusion of 0.3 μg·kg -1·h -1 until the end of operation. Ultrasound-guided SNB was performed after completion of intubation in both groups. The consumption of intraoperative fentanyl, propofol and remifentanil and the usage of vasoactive drugs were recorded. Before surgery (T 0), at 1 h after the start of surgery (T 1) and at the end of surgery (T 2), blood samples from the jugular bulbar and radial artery were collected, the jugular venous oxygen saturation was recorded, the arteriovenous oxygen content and cerebral oxygen uptake rate were calculated, and the occurrence of postoperative complications was also recorded. Results:Compared with group S, the consumption of fentanyl, propofol and remifentanil was significantly reduced, the usage rate of vasoactive drugs was decreased, the arteriovenous oxygen content and cerebral oxygen uptake rate were decreased at T 1 and T 2, the jugular venous oxygen saturation was increased, and the incidence of postoperative agitation was decreased in group DS ( P<0.05). Conclusions:Dexmedetomidine-SNB combined with general anesthesia can optimize the analgesic effect, improve cerebral oxygen supply and demand, reduce the occurrence of postoperative agitation when used in patients with acute TBI undergoing craniotomy.

OBJECTIVE: To investigate the effects of 4-methylcatechol (4MC) on the migration and inflammatory response in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS), as well as its underlying mechanisms of action. METHODS: RA-FLS was isolated from synovial tissue donated by RA patients, and the optimal concentration of 4MC was determined by cell counting kit 8 method for subsequent experiments, and the effect of 4MC on the migratory ability of RA-FLS was evaluated via a cell scratch assay. An inflammation model of RA-FLS was induced by tumor necrosis factor α (TNF-α). Real-time fluorescence quantitative PCR and ELISA were employed to detect the gene and protein expression levels of interleukin-1β (IL-1β) and IL-6 in RA-FLS and their culture supernatants, respectively, thereby investigating the anti-inflammatory effects of 4MC. Western blot was used to examine the expressions of nuclear factor κB (NF-κB) signaling pathway-related proteins, including inhibitor of NF-κB-α (IKBα), phosphorylated (P)-IκBα, NF-κB-inducing kinase α (IKKα), P-IKKαβ, P-p65, and p65. Cellular immunofluorescence was utilized to detect the expression and localization of p65 in RA-FLS, exploring whether 4MC exerts its anti-inflammatory effects by regulating the NF-κB signaling pathway. Finally, a collagen-induced arthritis (CIA) mouse model was established. The anti-RA effect of 4MC in vivo was evaluated by gross observation and histological examination. RESULTS: 4MC inhibited RA-FLS migration in a concentration-dependent manner. In the TNF-α-induced RA-FLS inflammation model, 4MC significantly decreased the gene and protein expression levels of IL-1β and IL-6. Furthermore, 4MC markedly reduced the ratios of P-IΚBα/IΚBα, P-IKKαβ/IKKα, and P-p65/p65, thereby blocking the transcriptional activity of p65 by inhibiting its nuclear translocation. This mechanism effectively suppressed the activation of the TNF-α-mediated NF-κB signaling pathway. Animal studies demonstrated that 4MC [10 mg/(kg·day)] significantly lowered serum levels of IL-1β, IL-6, and TNF-α, and alleviated arthritis severity and bone destruction in CIA mice. CONCLUSION 4MC not only inhibits the migration of RA-FLS but also mitigates their inflammatory response by suppressing the NF-κB signaling pathway, thereby effectively exerting its anti-RA effects.
Synoviocytes/metabolism* ; Arthritis, Rheumatoid/metabolism* ; Animals ; Cell Movement/drug effects* ; Humans ; Catechols/therapeutic use* ; Fibroblasts/drug effects* ; Mice ; Tumor Necrosis Factor-alpha/pharmacology* ; Interleukin-1beta/metabolism* ; Interleukin-6/metabolism* ; Signal Transduction/drug effects* ; NF-kappa B/metabolism* ; Transcription Factor RelA/metabolism* ; Synovial Membrane/cytology* ; Cells, Cultured ; Male ; Arthritis, Experimental ; Anti-Inflammatory Agents/pharmacology* ; NF-KappaB Inhibitor alpha ; Inflammation

Objective:To investigate the effect of ultrasound-guided scalp nerve block (SNB) combined with dexmedetomidine on cerebral blood flow after craniotomy in patients with acute traumatic brain injury (TBI).Methods:A randomized controlled design was conducted. Patients aged 25-65 years, with ASA physical status I–III and Glasgow Coma Scale scores of 9-12, who underwent craniotomy for acute TBI at Kunshan Traditional Chinese Medicine Hospital between January 2024 and February 2025 were selected. Patients with unstable vital signs, cranial tumors, cardiovascular diseases, local anesthetic allergies, or infections at the puncture site were excluded. Using a random number table, patients were divided into two groups: the ultrasound-guided SNB combined with dexmedetomidine group (SD group) and the dexmedetomidine-alone group (D group). General clinical data, peak systolic velocity (PSV), mean blood flow velocity (MBFV), intracranial pressure (ICP), S100 calcium-binding protein beta (S-100β protein), neuron-specific enolase (NSE) levels, and postoperative complications were compared. Dynamic changes in PSV and MBFV were analyzed using repeated measures analysis of variance, while inter-group comparisons used independent sample t-tests. Results:A total of 79 patients were included, with 40 in the SD group and 39 in the D group. There were no significant differences in general clinical data between the two groups (all P>0.05). In the D group, PSV and MBFV at T 1 and T 2 were significantly higher than at T0 [(125.04±20.43) cm/s vs. (126.83±21.76) cm/s vs. (110.63±18.49) cm/s, P=0.001; (61.75±8.34) cm/s vs. (62.81±8.54) cm/s vs. (57.82±6.93) cm/s, P=0.017], whereas no significant differences were observed in the SD group (all P>0.05). PSV, MBFV, ICP, S-100β protein, and NSE levels at T1 and T2 in the SD group were lower than those in the D group (all P<0.05). The incidence of postoperative hypertension, agitation, and the use rate of vasoactive drugs were also lower in the SD group compared to the D group (all P<0.05). Conclusion:The application of ultrasound-guided SNB combined with dexmedetomidine in TBI patients after craniotomy can help stabilize cerebral blood flow and ICP, mitigate neuronal injury, and reduce the incidence of postoperative complications.

Objective:To elucidate the molecular mechanisms through which high-dose dexamethasone exerts long-term effects on bone marrow mesenchymal stem cells (BMSCs), specifically its role in suppressing osteogenic differentiation, accelerating cellular senescence, triggering the senescence-associated secretory phenotype (SASP), and inducing apoptosis.Methods:Primary rat BMSCs were isolated and treated with high-dose dexamethasone (1×10 -4 mol/L) to establish the experimental group, while untreated cells served as the control. The gene and protein expression levels of osteogenic markers, bone alkaline phosphatase (bALP) and Runt-related transcription factor 2 (Runx2), were analyzed in both groups. Cellular senescence was evaluated using senescence-associated β-galactosidase (SA-β-gal) staining. The expression of senescence-related markers (P16 and P21), components of the senescence-associated secretory phenotype (SASP), including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and interferon (IFN)-γ, as well as apoptosis-related proteins (Bcl-2, Bax, and Cleaved-Caspase-3), and key factors of the Nrf2/HO-1 signaling pathway were assessed at both transcriptional and protein levels using qRT-PCR, immunofluorescence, and Western-blot analyses. These comprehensive evaluations aimed to determine the senescent state, apoptotic features, and alterations in osteogenic differentiation of BMSCs. Results:Following treatment with dexamethasone and subsequent withdrawal, both qRT-PCR and Western blot analyses indicated a significant reduction in the expression of the osteogenic markers bALP and Runx2 at both mRNA and protein levels. The proportion of SA-β-gal positive cells was markedly higher in the dexamethasone group (74.33%±6.89%) than in the control group (20.30%±1.57%, t=17.300, P<0.001). qRT-PCR analysis revealed upregulated mRNA expression of the senescence-related genes P16 and P21 after dexamethasone treatment, which was further supported at the protein level by immunofluorescence showing increased P21 expression. Western-blot results confirmed that protein expression levels of P16 and P21 were significantly elevated in the dexamethasone group (7.025±0.255 and 6.362±0.456, respectively) compared with the control group (1.016±0.115 and 0.816±0.172; both P<0.05). Furthermore, gene expression levels of the senescence-associated secretory phenotype (SASP) factors TNF-α and IL-1β were significantly increased (TNF-α: 3.539±0.599 vs. 0.742±0.095; IL-1β: 4.469±0.331 vs. 0.799±0.175; both P<0.05), and their protein expression was consistently upregulated as validated by Western-blot. Additionally, protein expression levels of TNF-α, IL-1β, and IFN-γ were significantly higher in the dexamethasone-treated group (3.476±0.932 vs. 0.945±0.095; 4.111±0.220 vs. 0.762±0.105; 2.155±0.240 vs. 0.656±0.104; all P<0.05).Western-blot analysis also demonstrated that protein expression of Nrf2 and HO-1 was significantly suppressed in the dexamethasone group (0.21±0.07 and 0.19±0.06, respectively) compared with the control group (1.13±0.15 and 0.92±0.21; P<0.05). Moreover, Western-blot analysis revealed that the expression levels of the pro-apoptotic proteins Bax and Cleaved-Caspase-3 were significantly up, regulated in the dexamethasone, treated BMSCs (Bax: 3.673±0.397 vs. 0.453±0.111; Cleaved-Caspase-3: 3.863±0.399 vs. 0.465±0.057), while the expression of the anti-apoptotic protein Bcl-2 was markedly down, regulated (0.959±0.073 vs. 2.126±0.195), with all differences being statistically significant ( P<0.05). Conclusions:High-dose dexamethasone treatment of BMSCs, followed by withdrawal of dexamethasone, induces cellular senescence and enhances the expression of the senescence-associated secretory phenotype (SASP) through suppression of the Nrf2/HO-1 signaling pathway. Concurrently, it promotes apoptosis by activating the mitochondrial apoptotic pathway, collectively leading to impaired osteogenic differentiation of BMSCs.

Objective:To evaluate the efficacy of dexmedetomidine-scalp nerve block (SNB) combined with general anesthesia in the patients with acute traumatic brain injury (TBI) undergoing craniotomy.Methods:In this randomized controlled trial, 74 American Society of Anesthesiologists Physical Status classification Ⅰ-Ⅲ patients of either sex with acute TBI, aged 30-78 yr, with body mass index of 18-30 kg/m 2, underwent craniotomy for hematoma evacuation combined with decompressive craniectomy at the Traditional Chinese Medicine Hospital of Kunshan from January to December 2024, of the Glasgow Coma Scale score 8-12, were selected and divided into 2 groups ( n=37 each) using a random number table method: dexmedetomidine combined with ultrasound-guided SNB group (DS group) and ultrasound-guided SNB group (S group). Before anesthesia, dexmedetomidine was infused as a loading dose of 1 μg/kg over 10 min followed by an infusion of 0.3 μg·kg -1·h -1 until the end of operation. Ultrasound-guided SNB was performed after completion of intubation in both groups. The consumption of intraoperative fentanyl, propofol and remifentanil and the usage of vasoactive drugs were recorded. Before surgery (T 0), at 1 h after the start of surgery (T 1) and at the end of surgery (T 2), blood samples from the jugular bulbar and radial artery were collected, the jugular venous oxygen saturation was recorded, the arteriovenous oxygen content and cerebral oxygen uptake rate were calculated, and the occurrence of postoperative complications was also recorded. Results:Compared with group S, the consumption of fentanyl, propofol and remifentanil was significantly reduced, the usage rate of vasoactive drugs was decreased, the arteriovenous oxygen content and cerebral oxygen uptake rate were decreased at T 1 and T 2, the jugular venous oxygen saturation was increased, and the incidence of postoperative agitation was decreased in group DS ( P<0.05). Conclusions:Dexmedetomidine-SNB combined with general anesthesia can optimize the analgesic effect, improve cerebral oxygen supply and demand, reduce the occurrence of postoperative agitation when used in patients with acute TBI undergoing craniotomy.

Objective To investigate the effect of different excipients of propofol on blood lipids and liver function during orthotopic liver transplantation. Methods Forty ASA Ⅲ- Ⅳ patients aged 40-64 yr weighing 50-75 kg undergoing orthotopic liver transplantation were randomly divided into 2 groups ( n = 20 each): propofol medium-chain triglycerides/long-chain triglycerides (MCT/LCT) group (group M) and propofol LCT group (group L). Anesthesia was induced with penehyclidine 1 mg, midazolam 0.04-0.06 mg/kg, sufentanil 0.6-0.8 μg/kg and propofol 1.5-2.0 mg/kg. Tracheal intubation was facilitated with vecuronium 0.10-0.15 mg/kg. The patients were mechanically ventilated. Anesthesia was maintained with 1%-2% isoflurane, continuous infusion of propofol blood samples were collected after admission into the operation room (T1), before skin incision (T2), at the end of pre-anhepatic phase (T3), at the end of anhepatic phase (T4) and 30 and 240 min of neohepatic phase (T5, T6 )for determination of plasma concentrations of triglyceride (TG), total cholesterol (CH), high-density-lipoproteincholesterol (HDL-C), low density-lipoprotein-cholesterol (LDL-C), and activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The changes in parameters from baseline values were calculated. Results Compared with group L, △TG was significant1y decreased at T4-6 in group M ( P ＜ 0.05 ) . There was no significant difference in △CH, △HDL-C, △LDL-C, △AST and △ALT,plasma concentrations of TG,CH, HDL-C and LDL-C,and activities of AST and ALT between the two groups ( P ＞ 0.05). Conclusion The effect of the two formulations of propofol on liver function is comparable. Propofol MCT/LCT exerts less effect on blood lipids during liver transplantation and is more suitable for this type of surgery.