Endotoxin-induced acute kidney injury (AKI) is commonly observed in clinical practice. Renal tubular epithelial cell (RTEC) pyroptosis is one of the main factors leading to the development of endotoxin-induced AKI. Mitochondrial dysfunction can lead to pyroptosis. However, the biological pathways involved in the potential lipopolysaccharide (LPS)-induced pyroptosis of RTECs, notably those associated with mitochondrial dysfunction, are poorly understood. Previous studies have demonstrated that heme oxygenase (HO)-1 confers cell protection via the induction of PTEN-induced putative kinase 1 (PINK1) expression through PTEN to regulate mitochondrial fusion/fission during endotoxin-induced AKI in vivo. Therefore, the present study investigated the role of HO-1/PINK1 in maintaining mitochondrial function and inhibiting the pyroptosis of RTECs exposed to LPS. Primary cultures of RTECs were obtained from wild-type (WT) and PINK1-knockout (PINK1KO) rats. An in vitro model of endotoxin-associated RTEC injury was established following treatment of the cells with LPS. The WT RTECs were divided into the control, LPS, Znpp + LPS and Hemin + LPS groups, and the PINK1KO RTECs were divided into the control, LPS and Hemin + LPS groups. RTECs were exposed to LPS for 6 h to assess cell viability, inflammation, pyroptosis and mitochondrial function. In the LPS-treated RTECs, the mRNA and protein expression levels of HO-1 and PINK1 were upregulated. Cell viability, adenosine triphosphate (ATP) levels and the mitochondrial oxygen consumption rate were decreased, whereas the inflammatory response, pyroptosis and mitochondrial reactive oxygen species (ROS) levels were increased. The cell inflammatory response and the induction of pyroptosis were inhibited, whereas the levels of mitochondrial ROS were decreased. In addition, the cell viability and ATP levels were increased in the WT RTECs following the upregulation of HO-1 expression. These effects were reversed by the downregulation of HO-1 expression. However, no statistically significant differences were noted between the LPS and the Hemin + LPS groups in the PINK1KO RTECs. Collectively, the findings of the present study indicate that HO-1 inhibits inflammation and regulates mitochondrial function by inhibiting the pyroptosis of LPS-exposed RTECs via PINK1.

Objective:To evaluate the effect of electroacupuncture on the heme oxygenase-1 (HO-1)/PTEN-induced putative kinase 1 (PINK1)/Parkin signaling pathway during acute kidney injury in endotoxemic rats.Methods:Twenty-four SPF healthy male Sprague-Dawley rats, aged 6-8 weeks, weighing 180-220 g, were divided into 4 groups ( n=6 each) by a random number table method: control group(group C), endotoxemia group(group E), acupoint electroacupuncture+ endotoxemia group(group EE), and non-acupoint electroacupuncture+ endotoxemia group(group NE). The endotoxemia model was developed by intraperitoneal injection of lipopolysaccharide 10 mg/kg. The equal volume of normal salinewas injected in group C. LPS 10 mg/kg was intraperitoneally injected in group E. In group EE, 30-min electroacupuncture was performed at bilateral Zusanli and Shenshu acupoints using disperse-dense waves with a frequency of 2/15 Hz to induce slight muscle tremor once a day starting from 5 days before developing the model, and the needle was retained until 6 h after injection. Electroacupuncture was performed at the points 0.5 cm lateral to the acupoints of Zusanli and Shenshu in group NE. The rats were anesthetized at 6 h after lipopolysaccharide injection, and blood samples from the femoral vein were obtained for determination of the serum creatinine (Cr) and urea nitrogen (BUN) concentrations(with a biochemical analyzer) and concentrations of neutrophil gelatinase-associated lipid transport protein (NGAL), interleukin-6 (IL-6), tumor necrosis factor (TNF-α) and kidney injury molecule-1(KIM-1) in serum (by enzyme-linked immunosorbent assay). Then the rats were sacrificed and kidney tissues were taken for determination of histological score of kidneys (HSK, using HE staining) and expression of HO-1, PINK1, Parkin, mitochondrial fusion protein 2(Mfn2), optic atrophy protein 1(OPA1) and mitochondrial dynamic-related protein 1 (Drp1) (by Western blot). Results:Compared with group C, serum concentrations of Cr, BUN, KIM-1, NGAL, IL-6 and TNF-α and HSK score of renal tissues were significantly increased, the expression of HO-1, PINK1, Parkin and Drp1 was up-regulated, and the expression of Mfn2 and OPA1 was down-regulated in E, EE and NE groups ( P<0.05). Compared with group E, serum concentrations of Cr, BUN, KIM-1, NGAL, IL-6 and TNF-α and HSK score of renal tissues were significantly decreased, and the expression of HO-1, PINK1, Parkin, Mfn2 and OPA1 was up-regulated, and Drp1 expression was down-regulated in group EE( P<0.05), and no significant change was found in the parameters mentioned above in group NE ( P>0.05). Conclusions:The mechanism by which electroacupuncture alleviates acute kidney injury is associated with activation of HO-1/PINK1/Parkin signaling pathway in endotoxemic rats.

Objective:To evaluate the effect of electroacupuncture (EA) on pyroptosis in renal tubular epithelial cells of rats with acute kidney injury (AKI) induced by endotoxin.Methods:Twenty-four healthy clean-grade Sprague-Dawley rats of either gender, aged 6-8 weeks, weighing 160-182 g, were divided into 4 groups ( n=6 each) using a random number table method: control group (group C), group AKI, EA plus AKI group (group EA), sham EA at non-acupoint plus AKI group (group SEA). The model of endotoxemia was established by intraperitoneally injecting 10 mg/kg lipopolysaccharide.Bilateral 30 min EA stimulation of Zusanli and Shenyu (according to atlas of animal acupoint) was performed starting from 5 days before establishing the model (once a day) and at 30 min before lipopolysaccharide administration on the day of establishing the model, with disperse-dense waves, frequency of 15 Hz, and the needle was kept until 6 h after injection of LPS in group EA.EA was performed at the points 0.5 cm lateral to the acupoints of Zusanli and Shenyu in group SEA.At 6 h after LPS injection, blood was taken from the heart, and the concentrations of serum blood urea nitrogen (BUN) and creatinine (Cr) were detected by an automatic biochemical analyzer, and the serum concentrations of neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) by enzyme-linked immunosorbent assay.The rats were then sacrificed, and the left renal cortex was obtained for determination of pyroptosis rate of renal tubular epithelial cells (by TUNEL). The right renal cortex was obtained to detect the expression of caspase-1 and IL-1β by Western blot, and the expression of caspase-1 mRNA and IL-1β mRNA was detected by real-time polymerase chain reaction. Results:Compared with group C, the concentrations of BUN, Cr, NGAL, KIM-1, TNF-α, and IL-6 were significantly increased, the pyroptosis rate of renal tubular epithelial cells was increased, the expression of caspase-1 and IL-1β protein and mRNA in the renal cortex was up-regulated in group AKI ( P<0.05). Compared with group AKI, the concentrations of BUN, Cr, NGAL, KIM-1, TNF-α, and IL-6 were significantly decreased, the pyroptosis rate of renal tubular epithelial cells was decreased, the expression of caspase-1 and IL-1β protein and mRNA in the renal cortex was down-regulated in group SEA ( P>0.05). Conclusion:The mechanism by which EA reduces AKI may be related to inhibiting pyroptosis in renal tubular epithelial cells of rats.

Increasing lines of evidence identified that dexmedetomidine (DEX) exerted protective effects against sepsis-stimulated acute lung injury via anti-inflammation, anti-oxidation and anti-apoptosis. However, the mechanisms remain unclear. Herein, we investigated whether DEX afforded lung protection by regulating the process of mitochondrial dynamics through the HIF-1a/HO-1 pathway in vivo and in vitro. Using C57BL/6J mice exposed to lipopolysaccharide, it was initially observed that preemptive administration of DEX (50μg/kg) alleviated lung pathologic injury, reduced oxidative stress indices (OSI), improved mitochondrial dysfunction, upregulated the expression of HIF-1α and HO-1, accompanied by shifting the dynamic course of mitochondria into fusion. Moreover, HO-1-knockout mice or HO-1 siRNA transfected NR8383 cells were pretreated with HIF-1α stabilizer DMOG and DEX to validate the effect of HIF-1a/HO-1 pathway on DEX-mediated mitochondrial dynamics in a model of endotoxin-induced lung injury. We found that pretreatment with DEX and DMOG distinctly relieved lung injury, decreased the levels of mitochondrial ROS and mtDNA, reduced OSI, increased nuclear accumulation of HIF-1a and HO-1 protein in wild type mice but not HO-1 KO mice. Similar observations were recapitulated in NC siRNA transfected NR8383 cells after LPS stimulation but not HO-1 siRNA transfected cells. Concertedly, DEX reversed the impaired mitochondrial morphology in LPS stimulated-wild type mice or NC siRNA transfected NR8383 cells, upregulated the expression of mitochondrial fusion protein, while downregulated the expression of fission protein in HIF-1a/HO-1 dependent pathway. Altogether, our data both in vivo and in vitro certified that DEX treatment ameliorated endotoxin-induced acute lung injury by preserving the dynamic equilibrium of mitochondrial fusion/fission through the regulation of HIF-1a/HO-1 signaling pathway.

Sepsis caused acute lung injury (ALI) is a kind of serious disease in critically ill patients with very high morbidity and mortality. Recently, it has been demonstrated that Golgi is involved in the process of oxidative stress. However, whether Golgi stress is associated with oxidative stress in septic induced acute lung injury has not been elucidated. In this research, we found that lipopolysaccharide (LPS) induced oxidative stress, apoptosis, inflammation and Golgi morphology changes in acute lung injury both in vivo and in vitro. The knockout of heme oxygenase-1(HO-1) aggravated oxidative stress, inflammation, apoptosis and reduced the expression of Golgi matrix protein 130 (GM130), mannosidase Ⅱ, Golgi-associated protein golgin A1 (Golgin 97), and increased the expression of Golgi phosphoprotein 3 (GOLPH3), which caused the fragmentation of Golgi. Furtherly, the activation of hypoxia inducible factor-1α (HIF-1α)/HO-1 pathway, attenuates Golgi stress and oxidative stress by increasing the levels of GM130, mannosidase Ⅱ, Golgin 97, and decreasing the expression of GOLPH3 both in vivo and in vitro. Therefore, the activation of HO-1 plays a crucial role in alleviating sepsis-induced acute lung injury by regulating Golgi stress, oxidative stress, which may provide a therapeutic target for the treatment of acute lung injury.

Neuropathic pain is a kind of intractable pain syndrome, and its pathogenesis has always been a hot and difficult point in pain medical research. Recent studies have shown that microglia polarization and the consequent pro-inflammatory reaction play a crucial role in the neuropathic pain. Microglia can be polarized to "classical activation" M1 or "alternatively activated" M2 during neuroinflammation and exert neurotoxic or neuroprotective effects in the nervous system. This article focuses on the relationship between microglia polarization and neuropathic pain, and explores how to use the neuroprotective and anti-inflammatory properties of microglia to develop new targeted drugs and searches out a new way for the treatment of the neuropathic pain.

Various pharmacological agents and protective methods have been shown to reverse pneumoperitoneum-related lung injury, but identifying the best strategy is challenging. Herein, we employed lung tissues and blood samples from C57BL/6 mice with pneumoperitoneum-induced lung injury and blood samples from patients who received laparoscopic gynecological surgery to investigate the therapeutic role of hydromorphone in pneumoperitoneum-induced lung injury along with the underlying mechanism. We found that pretreatment with hydromorphone alleviated lung injury in mice that underwent CO2 insufflation, decreased the levels of myeloperoxidase (MPO), total oxidant status (TOS), and oxidative stress index (OSI), and increased total antioxidant status (TAS). In addition, after pretreatment with hydromorphone, upregulated HO-1 protein expression, reduced mitochondrial DNA content, and improved mitochondrial morphology and dynamics were observed in mice subjected to pneumoperitoneum. Immunohistochemical staining also verified that hydromorphone could increase the expression of HO-1 in lung tissues in mice subjected to CO2 pneumoperitoneum. Notably, in mice treated with HO-1-siRNA, the protective effects of hydromorphone against pneumoperitoneum-induced lung injury were abolished, and hydromorphone did not have additional protective effects on mitochondria. Additionally, in clinical patients who received laparoscopic gynecological surgery, pretreatment with hydromorphone resulted in lower serum levels of club cell secretory protein-16 (CC-16) and intercellular adhesion molecule-1 (ICAM-1), a lower prooxidant-antioxidant balance (PAB), and higher heme oxygenase-1 (HO-1) activity than morphine pretreatment. Collectively, our results suggest that hydromorphone protects against CO2 pneumoperitoneum-induced lung injury via HO-1-regulated mitochondrial dynamics and may be a promising strategy to treat CO2 pneumoperitoneum-induced lung injury.

Objective To evaluate the effect of sufentanil on apoptosis in spinal cord neurons of mice with peripheral nerve injury. Methods One hundred and fifty clean-grade healthy male BALB∕c mice, aged 6-8 weeks, weighing 18-22 g, were divided into 3 groups ( n=50 each) using a random number table method: sham operation group (group Sham), peripheral nerve injury group (group PNI) and sufentanil group ( group SF) . The model of unilateral sciatic nerve injury was established in PNI and SF groups. After establishing the model, sufentanil 5. 0 μg∕kg was intraperitoneally injected once a day for 3 consecutive days in group SF, while the equal volume of normal saline was given instead of sufentanil in Sham and PNI groups. Five mice in each group were sacrificed at days 1, 3, 7, 14 and 28 after surgery ( T0-4 ) , and L4-6 segments of the injure ipsilateral spinal cord were removed for examination of pathological changes ( with a light microscope) and for determination of neuronal apoptosis ( by TUNEL assay) . The ap-optosis index ( AI) was calculated. Five mice in each group were sacrificed at T0-4 , and L4-6 segments of the injured ipsilateral spinal cord were removed for detection of the expression of Bcl-2, Bax and cleaved caspase-3 by Western blot. The ratio of Bcl-2 expression to Bax expression ( Bcl-2∕Bax ratio) was calculat-ed. Results Compared with group Sham, the AI was significantly increased, the expression of Bcl-2 pro-tein was down-regulated, and the expression of cleaved caspase-3 and Bax was up-regulated in PNI and SF groups ( P<0. 05) . Compared with group PNI, the AI was significantly decreased, the expression of Bcl-2 protein was up-regulated, the expression of cleaved caspase-3 and Bax was down-regulated, the Bcl-2∕Bax ratio was increased (P<0. 05), and the pathological changes were significantly attenuated in group SF. Conclusion Sufentanil can inhibit apoptosis in spinal cord neurons of mice with peripheral nerve injury.