Acute lung injury is a common complication of sepsis and characterized by a high mortality rate during hospitalization. Proanthocyanidin, which are abundant compounds found in various plants, have shown promising effects in preventing chronic diseases, and their oligomers have attracted attention for their high bioavailability and strong antioxidant activity. In recent years, there have been suggestions that oligomeric proanthocyanidin may possess lung-protective properties, however, the specific mechanisms involved have not been fully elucidated. This study reveals that the therapeutic efficacy of oligomeric proanthocyanidin in mitigating lung injury during sepsis, achieved through the reduction of neutrophil extracellular traps accumulation and the attenuation of inflammation, can be attributed to the capacity to safeguard the integrity of the intestinal mucus layer and the intestinal barrier. This protective action results in a decrease in endotoxin entry into the bloodstream and bacterial translocation, both of which can trigger neutrophil extracellular traps causing further lung injury.

Acute lung injury (ALI) linked to sepsis has a high mortality rate, with limited treatment options available. In recent studies, medical ozone has shown the potential to alleviate inflammation and infection. Here, we aimed to evaluate therapeutic potential of medical ozone in a mouse model of the sepsis-induced ALI by measuring behavioral assessments, lung function, and blood flow. Protein levels were quantified by Western blotting. In vitro, we performed experiments on bone marrow-derived macrophages (BMDMs) to investigate the effect of adenosine monophosphate (AMP)-activated protein kinase (AMPK) inhibitors and agonists on their phagocytic activity. The results showed that medical ozone significantly improved the survival rate, ameliorated lung injury, and enhanced lung function and limb microcirculation in mice with ALI. Notably, medical ozone inhibited the formation of neutrophil extracellular traps (NETs), a crucial factor in the ALI development. Additionally, medical ozone counteracted the elevated levels of tissue factor, matrix metalloproteinase-9, and interleukin-1β. In the ALI mice, the effects of ozone were abolished, and BMDMs showed an impaired capacity to engulf NETs following the Sr-a1 knockout. Under normal physiological conditions, the administration of an AMPK antagonist showed similar effects on the Sr-a1 knockout, significantly inhibiting the phagocytosis of NETs by BMDMs. In contrast, AMPK agonists enhanced this phagocytic process. In conclusion, medical ozone may alleviate the sepsis-induced lung injury through the AMPK/SR-A1 pathway, thereby enhancing the phagocytosis of NETs by macrophages.

Abstract Background Respiratory variation in the internal jugular vein (IJVV) has not shown promising results in predicting volume responsiveness in ventilated patients with low tidal volume (Vt) in prone position. We aimed to determine whether the baseline respiratory variation in the IJVV value measured by ultrasound might predict fluid responsiveness in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion (PSF) with low Vt. Methods According to the fluid responsiveness results, the included patients were divided into two groups: those who responded to volume expansion, denoted the responder group, and those who did not respond, denoted the non-responder group. The primary outcome was determination of the value of baseline IJVV in predicting fluid responsiveness (≥15% increases in stroke volume index (SVI) after 7 ml·kg-1 colloid administration) in patients with AIS undergoing PSF during low Vt ventilation. Secondary outcomes were estimation of the diagnostic performance of pulse pressure variation (PPV), stroke volume variation (SVV), and the combination of IJVV and PPV in predicting fluid responsiveness in this surgical setting. The ability of each parameter to predict fluid responsiveness was assessed using a receiver operating characteristic curve. Results Fifty-six patients were included, 36 (64.29%) of whom were deemed fluid responsive. No significant difference in baseline IJVV was found between responders and non-responders (25.89% vs. 23.66%, p = 0.73), and no correlation was detected between baseline IJVV and the increase in SVI after volume expansion (r = 0.14, p = 0.40). A baseline IJVV greater than 32.00%, SVV greater than 14.30%, PPV greater than 11.00%, and a combination of IJVV and PPV greater than 64.00% had utility in identifying fluid responsiveness, with a sensitivity of 33.33%, 77.78%, 55.56%, and 55.56%, respectively, and a specificity of 80.00%, 50.00%, 65.00%, and 65.00%, respectively. The area under the receiver operating characteristic curve for the baseline values of IJVV, SVV, PPV, and the combination of IJVV and PPV was 0.52 (95% CI, 0.38–0.65, p=0.83), 0.54 (95% CI, 0.40–0.67, p=0.67), 0.58 (95% CI, 0.45–0.71, p=0.31), and 0.57 (95% CI, 0.43–0.71, p=0.37), respectively. Conclusions Ultrasonic-derived IJVV lacked accuracy in predicting fluid responsiveness in patients with AIS undergoing PSF during low Vt ventilation. In addition, the baseline values of PPV, SVV, and the combination of IJVV and PPV did not predict fluid responsiveness in this surgical setting. Trail registration This trial was registered at www.chictr.org (ChiCTR2200064947) on 24/10/2022. All data were collected through chart review.

目的 探讨将生理盐水和空气注入一次性使用气管导管套囊后囊内压力的变化.方法 在体实验:拟选入全身麻醉下择期行妇科手术的成人患者40例,随机分为生理盐水组(S组)和空气组(A组),两组各20例.两组均在气管插管后用10ml注射器注入适量生理盐水或空气,并由同一名操作者凭经验以手触摸法评估囊内压至合适范围.使用压力换能器监测囊内压.拔管后,在同一根气管导管注射同等量的介质监测囊内压.套囊对气管壁压力等于插管后的囊内压减去插管前的囊内压.体外实验:实验共采用气管导管(ID 7.0 mm)40根,随机分为两组,每组20根,S组为生理盐水组,A组为空气组.以1ml为间隔间断向一次性气管导管套囊内分别注射生理盐水或者空气至10 ml,记录套囊内压力变化.结果 在体实验:S组气管导管套囊对气管壁压力与A组比较差异有统计学意义,S组明显高于A组(P＜0.05).体外实验:同等容量的介质注入S组和A组间囊内压力差异无统计学意义(P =0.154).结论 在缺乏有效的囊内压力监测设备的情况下,预先在一次性使用气管导管套囊内注射空气直至指感触压法感觉到合适压力,然后将空气抽净,再注入同样体积的生理盐水,该法可以避免经验性直接注入生理盐水后产生的过高的囊内压,从而减少对气道黏膜的损伤.

Objective To investigate the effects of cannabinoid receptor 2 (cannabinoid receptor 2,CB2R) agonist JWHO15 on the hyperalgesia induced by remifentanil in a rat model of postoperative pain.Methods Sixty SD rats were randomly divided into 10 groups ( n =6 each ):control groups ( C1 and C2 ),incisional pain groups (I1 and I2),incisional pain plus JWHO15 groups (QI and FI),remifentanil groups (R1 and R2),and JWHO15 plus remifentanil groups ( QR and FR).Rats in group QL/QR and FI/FR were intrathecal injection with 10μg JWHO15 ( diluted in 10μl 20％ DMSO solution) and intraperitoneal administration with 100μg JWHO15 ( diluted in 10μl 4％ DMSO solution) respectively 30 min before plantar incision while rats in group C,I and R were received with the same volume of DMSO solution.Plantar incision surgery was operated in rats of group I,R,QI/FI,and QR/FR.In group R and QR/FR,remifentanil (0.04 mg/kg) was infused subcutaneously to rats with a pump for 30 min at the moment of surgical incision.The paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) at 24 h before incision and at 2 h,6 h,24 h and 48 h after incision were tested to evaluate the behavioral changes.Results Compared with group C and baseline,the level of PWMT and PWTL decreased at 2 h,6 h,24 h and 48h after incision in group Ⅰ (P＜ 0.01 ) ;Compared with group Ⅰ,the significant decrease of PWMT and PWTL were observed after incision in group R (P ＜ 0.05 ) ; Compared with group R,the significant increase of PWMT (7.78 ± 1.09) and PWTL ( 17.28 ± 1.58) were observed from 6 h after incision in group QR(P＜0.05).And the increase of PWMT (7.79 ±0.72,9.50 ± 1.17,7.86 ± 1.16) and PWTL ( 16.23 ± 1.50,19.53 ± 1.63,18.10 ± 0.93) were observed at 6 h,24 h and 48 h after incision in group FR(P＜0.05).Conclusion Intrathecal and intraperitoneal administration of JWHO15 in this investigation dose could relief remifentanil-induced hyperalgesia in a rat model of postoperative pain.

N-methyl-D-aspartate receptor (NMDAR) and metabotropic glutamate receptor 5 (mGluR5) play an important role in nociceptive processing and central sensitization. Our previous study showed that tyrosine phosphorylation of NMDAR subunit 2B (NR2B) at Tyr1472 in spinal dorsal horn contributes to the postoperative hyperalgesia induced by remifentanil. Cyclin-dependent kinase 5 (Cdk5) has been implicated in synaptic plasticity, learning, memory and pain signaling via regulating the phosphorylation of NMDAR and mGluR5. In the present study, a rat model of postoperative pain was used to investigate the role of Cdk5 in spinal dorsal horn in remifentanil-induced hyperalgesia and the intervention of pretreatment with Cdk5 inhibitor roscovitine. Intraoperative infusion of remifentanil (0.04 mg/kg, subcutaneous) significantly enhanced mechanical allodynia and thermal hyperalgesia induced by plantar incision during the postoperative period (each lasting between 2 h and 48 h), which were attenuated by pretreatment with roscovitine. Correlated with the pain behavior changes, Western blotting revealed that there was a significant increase in the expression of Cdk5 and its activator p35/p25, and further the kinase activity of Cdk5 in spinal dorsal horn after intraoperative infusion of remifentanil. The phosphorylation of NR2A at Ser1232, the phosphorylation of NR2B at Tyr1472 and the phosphorylation of mGluR5 at Ser1167 were also significantly up-regulated. Furthermore, these increases were attenuated by pretreatment with roscovitine. These results suggested that Cdk5 may contribute to remifentanil-induced postoperative hyperalgesia via regulating the phosphorylation of NMDAR and mGluR5 in spinal dorsal horn. These findings provide experimental evidence for the further application of Cdk5 inhibitor in preventing remifentanil-induced hyperalgesia.

BACKGROUNDS The cyclic AMP response element-binding protein (CREB) plays an important role in neuropathic pain. Kinesin superfamily motor protein 17 (KIF17) is involved in long-term memory formation. CREB could increase the level of KIF17 when activated by synaptic input. This study is to investigate the role and mechanism of CREB antisense oligonucleotide (ODN) in neuropathic pain induced by chronic constriction injury (CCI) in mice. RESULTS CCI surgery decreased thresholds of mechanical allodynia and thermal hyperalgesia whereas CREB antisense oligonucleotide ODN significantly attenuated these pain behaviors (P < 0.05). CCI significantly induced the protein expression of phosphorylated CREB (pCREB) and KIF17, but not KIF5B, in the spinal cord of CCI mice (P < 0.05). Additionally, the mRNA expression of CREB and KIF17 was significantly increased by CCI (P < 0.05). However, CREB antisense ODN significantly decreased the protein expression of pCREB and KIF17 (but not KIF5B), and the mRNA expression of CREB and KIF17 (P < 0.05). CONCLUSIONS CREB antisense oligonucleotide ODN may reduce neuropathic pain through targeting CREB and decreasing the expression of pCREB and KIF17.

BACKGROUND:Hyperalgesia and neuroinflammation are associated with glia, which consists of macroglia and microglia. In this study, we used a selective cannabinoid receptor type 2 (CB2) agonist JWH015 to investigate remifentanil-induced postoperative hyperalgesia.METHODS:Mechanical allodynia and thermal hyperalgesia after postoperative hyperalgesia and intrathecal injection of JWH015 were assessed by the paw withdrawal mechanical threshold and paw withdrawal thermal latency tests. We used immunohistochemistry and immunoblotting to investigate the effect of JWH015 on CB2 receptor, NR2B subunits, activated glial cells, and proinflammatory cytokine expression in rats after remifentanil-induced postoperative hyperalgesia.RESULTS:Postoperative hyperalgesia was induced by intraoperative infusion of remifentanil. Glial cells were activated, and expression levels of several genes were significantly increased, including interleukin 6, tumor necrosis factor α, CB2, and the NR2B subunit phosphorylated at Tyr-1472 (p-NR2B). Intrathecal injection of JWH015 significantly inhibited glial cell activation, suppressed expression of interleukin 6, tumor necrosis factor α, and p-NR2B, and stimulated CB2 expression, thus attenuating postoperative hyperalgesia. However, these phenomena were abolished in the group that was preadministered with AM630.CONCLUSIONS:The activation of glia, the production of proinflammatory cytokines, and the expression of CB2 and p-NR2B in the spinal dorsal horn increase significantly during the process of remifentanil-induced hyperalgesia. These changes can be regulated by pretreatment with JWH015, which may be the main mechanism underlying the antihyperalgesia effects of JWH015.

Background: The mammalian target of rapamycin (mTOR) is known to regulate cell growth, and it also participates in pain transmission as has been recently verified in inflammatory and neuropathic pain models. The targeting of mTOR represents a new strategy for the control of chronic pain. In the present study, we investigated the effect of mTOR in the expression of PSD95 and NR2B-PSD95 or GluA2-PSD95 interaction ratio in a chronic constriction injury (CCI) mice model.Methods: Paw mechanical withdrawal threshold (PMWT) and paw withdrawal thermal latency (PWTL) were respectively used to assess mechanical allodynia and thermal hyperalgesia after CCI operation and intrathecal injection of rapamycin. Western blot and co-immunoprecipitation were used to investigate the effects of rapamycin on the expression of PSD95 and interaction ratio of NR2B-PSD95 or GluA2-PSD95 in the spinal dorsal horn of mice.Results: Our study demonstrated that the inhibition of spinal mTOR with intrathecal injections of rapamycin (1 mu g/5 mu L) for days 1-6 after CCI surgery led to an obvious decrease in CCI-induced neuropathic pain. Rapamycin significantly reduced the PMWT of CCI mice, whereas there was no significant effect on PWTL. The active form of the mTOR signaling pathway (p-mTOR, p-4EBP1 and p-p70S6k) at the spinal level remarkably increased in CCI mice, and rapamycin could inhibit this up-regulation. The increased expression of PSD95 and the interaction ratio of GluA2-PSD95 or NR2B-PSD95 could also be inhibited by intrathecal injection of rapamycin.Conclusion: These data suggest that the mTOR pathway is activated in the spinal dorsal horn in CCI-induced neuropathic pain, and the intrathecal injection of rapamycin can reduce mechanical allodynia. Our findings indicate that spinal mTOR is an important component of CCI-induced neuropathic pain, and mTOR may be a potential target for chronic pain therapy. (C) 2013 Published by Elsevier Inc.

Objective To investigate the effects of repeated intrathecal cyclic AMP response elementbinding protein (CREB) antisense oligodeoxynucleotide (ODN) on the expression of NR2A in spinal cord in mice with neuropathic pain produced by chronic constrictive injury of the sciatic nerve (CCI).Methods Forty C57BL/6 male mice in which intrathecal catheter was successfully implanted were randomly divided into 4 groups ( n =10 each):normal saline group (group NS),CREB sense ODN group (group S),CREB missense ODN group (group M),and CREB antisense ODN group (group A).In groups NS,S,M and A,normal saline 5μl,sense ODN 5 μg/5 μl,missense ODN 5 μg/5 μl and antisense ODN 5 μg/5 μl were injected intrathecally once a day for 6 days,starting from the 1st day after CCI,respectively.Paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) were measured on day 1 before CCI and on day 1,3,5 and 7 after CCI.Five mice from each group were sacrificed on day 7 and 14 after CCI and the lumbar segment of the spinal cord (L3-5 )was removed for determination of NR2A expression using Western blot and RT-PCR.Results Compared with the baseline value,no significant change was found in PWMT and PWTL on day 1-7 after CCI in group A ( P ＞0.05),while PWMT and PWTL were significantly decreased on day 1-7 after CCI in groups NS,S and M (P ＜0.05).Compared with groups NS,S and M,the expression of NR2A mRNA and protein was significantly downregulated on day 7 and 14 after CCI in group A ( P ＜ 0.05).The expression of NR2A mRNA and protein was significantly up-regulated on day 14 after CCI compared with that on day 7 after CCI in all the groups.Conclusion Intrathecal CREB antisense ODN during the development of neuropathic pain can attenuate neuropathic pain and inhibition of the expression of NR2A in mouse spinal cord may be involved in the mechanism.

Objective To investigate the effect of cannabinoid receptor 2 (CB2R) agonist JWH015 on the hyperalgesia induced by remifentanil in a rat model of incision pain. Methods Thirty Sprague-Dawley (SD) rats were randomly divided into 5 groups (n=6):control group(group C),incisional pain group(group I),incisional pain plus JWH015 group (group JI),remifentanil group (group R),and JWH015 plus remifentanil group (group JR).10 μg JWH015 diluted by 10 μl 20％ dimethyl sulfoxide (DMSO)solution was intrathecally injected in each rat of group JI and JR 30 min before plantar incision,while group C,I and R received the equivalent amount of normal saline 20％ DMSO 10 μl in the same way.Plantar incision surgery was operated in group I,R,JI,and JR.In group R and JR,remifentanil (0.04 mg/kg,0.4 ml) was infused subcutaneously with a pump for 30 min at the moment of surgical incision.The other groups were received the equivalent amount of normal saline (0.4 ml) instead of remifentanil.The paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) were measurd one day before and at 2,6,24 and 48 h after incision. Results Compared with group C and the baseline,the level of PWMT and PWTL significantly decreased at 2,6,24 and 48 h after incision in group I (P＜0.05); Compared with group I,the significant decrease of PWMT (6.3±0.8),(6.4±0.8),(6.3± 1.0),(6.8±0.9) g and PWTL( 12.8± 1.2),(12.2±0.9),( 13.4± 1.1 ),( 13.5± 1.3 ) s were observed after incision in group R (P＜0.05).Compared with group R,the significant increase of PWMT (7.9±1.0),(9.9±1.1),(8.4±1.1) g and PWTL (17.3±1.9),(19.9±1.3),(17.7±1.2) s were observed at 6,24 and 48 h after incision in group JR (P＜0.05). Conclusions Intrathecal injection of JWH015 can be effectively alleviated remifentanil-induced hyperalgesia in a rat model of incision pain.

Objective To investigate the effects of intrathecally cyclic AMP response element-binding protein(CREB) antisense oligodeoxynucleotide (ODN) on neuropathic pain behaviors.Methods Using mouse model of neuropathic pain induced by chronic constriction injury of sciatic nerve (CCI),24 male C57BL/6 mice successfully received intrathecal catheter implantation and without motor dysfunction were randomly divided into 4groups(n=6):Saline group(NS),CREB sense ODN group(S),CREB missense ODN group(M),CREB antisense ODN group(A).Mice in NS,S,M and A were intrathecally treated with Saline 5μ l,Sense ODN 5μg/5μl,Missense ODN 5μg/5μl and Antisense ODN 5μg/Sμl once daily on day 1 ～6 after CCI respectively.Paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency(PWTL) were tested on day 1 before CCI and day 1,3,5,7,10,14,17,21 after CC(I).Results Mice in A group maintained the pain thresholds in the baseline and lasted at least 7 days after CCI ( 7 d,PWMT:( 0.81 ± 0.20 ) g vs ( 1.00 ± 0.19 ) g,P ＞ 0.05 ;PWTL:(5.96 ± 0.69) s vs (6.93 ± 1.08 ) s,P ＞ 0.05 ).The withdrawal thresholds in the ipsilateral hind paws of the mouse were significantly lower than baseline in A group on day 10 after CCI( 10 d,PWMT:(0.56 ±0.19)g vs (1.00±0.19)g,P＜0.05; PWTL:(3.93 ±0.28)s vs (6.93 ± 1.08)s,P＜0.05).Compared with NS group ( 10 d,PWMT:(0.56 ±0.19)g vs (0.37 ±0.08)g,P＜0.05; PWTL:(3.93 ±0.28)s vs (3.14 ±0.45)s,P＜0.05),S group,M group,the withdrawal thresholds of A group was significantly elevated on day 10 after CCI.These effects lasted up to at least day 21 after CCI.Conclusion Intrathecally treated with CREB antisense ODN in the development of neuropathic pain induced by CCI completely improved pain behaviors during the course of injection,and the effects of relief pain lasted at least 15d after no injection.