Rhein Protects Against Neurological Deficits After Traumatic Brain Injury in Mice via Inhibiting Neuronal Pyroptosis.

Neurological dysfunction provoked by traumatic brain injury (TBI) makes a huge impact on individual learning ability, memory level, social participation, and quality of life. Pyroptosis, the caspase-1-dependent cell death, which is associated with the release of numerous pro-inflammatory factors, plays a major role in the pathological process after TBI. Inhibition of pyroptosis has been shown to be an attractive strategy for the treatment of various neurological disorders. Here, we found that Rhein, an anthraquinone derived from the medicinal plant rhubarb, attenuated TBI-induced upregulation of pro-inflammatory cytokines, blood lactate dehydrogenase (LDH), and pyroptosis-related proteins, as well as reduced neurological dysfunction in a mouse TBI model. Consistently, Rhein inhibitd equiaxial stretch-induced neuron pyroptosis, LDH release, and upregulation of pro-inflammatory factors in vitro. Thus, our study suggested that Rhein protected against neurological deficits after TBI via inhibiting neuronal pyroptosis.

Hydrogen alleviated organ injury and dysfunction in sepsis: The role of cross-talk between autophagy and endoplasmic reticulum stress: Experimental research.

AIMS: Sepsis is defined as a life-threatening organ dysfunction that is caused by a dysregulated host response to infection. Although much progress has been made in understanding the pathophysiology of sepsis, further discussion and study of the detailed therapeutic mechanisms are needed. Autophagy and endoplasmic reticulum stress are two pathways of the complicated regulatory network of sepsis. Herein, we focus on the cellular mechanism in which autophagy and endoplasmic reticulum stress participate in hydrogen (H2)-protected sepsis-induced organ injury. MATERIALS AND METHODS: Male C57BL/6 mice were randomly divided into the following groups: control group, cecal ligation puncture (CLP) group, CLP + tunicamycin(TM) group, CLP + 4-phenyl butyric acid (4-PBA) group, CLP + rapamycin (Rap) group, CLP + 3-methyladenine (3-MA) group, CLP + H2 group, CLP + H2 + 3-MA group, and CLP + H2 + TM group. After the experiment was completed, autophagosome was detected by transmission electron microscopy; protein PKR-like ER kinase (PERK), p-PERK, Eukaryotic translation initiation factor-2α (eIF2α), p-eIF2α, inositol-requiring enzyme1α(IRE1α), C/EBP homologous protein(CHOP), activating transcription factor(ATF), XBP-1, microtubule-associated protein 1 light(LC3), Beclin1, PTEN-induced putative kinase 1(PINK1), Parkin, and p65 subunit of Nuclear factor kappa B(NF-κb) were measured by Western blot; myeloperoxidase(MPO) activity in lung, bronchoalveolar lavage(BAL) total protein, lung wet-to-dry(W/D) ratio, serum biochemical indicators, 7-day survival rate, and pathological injury scores of lung, liver, and kidney were tested; and cytokines tumor necrosis factor-α(TNF-α), Interleukin(IL)-1ß, and IL-6 and high mobility group box protein (HMGB)1 were detected by enzyme-linked immunosorbent assay(ELISA). RESULTS: We demonstrated that sepsis induced endoplasmic reticulum stress. Moreover, it was found that an increase in endoplasmic reticulum impaired autophagy activity in sepsis, and the absence of endoplasmic reticulum stress attenuated tissue histological injury and dysfunction of lung, liver, and kidney in septic mice. Intriguingly, hydrogen alleviated the endoplasmic reticulum stress via the autophagy pathway and also mitigated inflammation and organ injury. CONCLUSION: Hydrogen provided protection from organ injury induced by sepsis via autophagy activation and endoplasmic reticulum stress pathway inactivation.

Electroacupuncture alleviates morphine­induced hyperalgesia by regulating spinal CB1 receptors and ERK1/2 activity.

Electroacupuncture (EA), a traditional Chinese therapeutic technique, is considered an effective method for treating certain painful neuropathies induced by various neuropathological damage. The current study investigated the effect of EA on intrathecal (IT) morphine­induced hyperalgesia (MIH) and examined the hypothesis that activation of cannabinoid receptor 1 (CB1) could enhance the antinociceptive effect of EA on MIH via regulation of the extracellular signal­regulated kinase 1/2 (ERK1/2) signaling pathway. Using a rat model of IT MIH, mechanical and thermal hyperalgesia were evaluated by an electronic von Frey filament and hotplate at baseline (1 day before IT administration) and at days 1, 3, 5 and 7 after IT administration. Rats received IT normal saline, IT morphine or IT morphine + EA at ST36­GB34. The protein levels of ERK1/2, phosphorylated (p)­ERK1/2 and CB1 in the spinal cord were assayed by western blotting. Furthermore, the effect of IT injection of the CB1 agonist WIN 55,212­2 and the CB1 antagonist SR141716 on the antinociceptive effect of EA in rats with MIH was investigated. Nociceptive behavior and ERK1/2, phosphorylated (p)­ERK1/2 and CB1 protein levels were evaluated as mentioned above. The results revealed that chronic IT injections of morphine induced a significant decrease in mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) accompanied with remarkable upregulation of p­ERK1/2 in the spinal cord, which could be attenuated by EA at the ST36­GB34 acupoints. In the rat model of MIH, IT injection of WIN 55,212­2 combined with EA induced a significant increase in MWT and TWL accompanied with a significant decrease in p­ERK1/2 and a significant increase in CB1 protein level compared with EA alone, while SR141716 induced the opposite results. The present study suggests that EA alleviates hyperalgesia induced by IT injection of morphine partially through the inhibition of ERK1/2 activation. Activation of the CB1 receptor enhances the antinociceptive effect of EA in rats with MIH partly through the regulation of the spinal CB1­ERK1/2 signaling pathway.

Hyperbaric oxygen preconditioning attenuates postoperative cognitive impairment in aged rats.

Cognitive decline after surgery in the elderly population is a major clinical problem with high morbidity. Hyperbaric oxygen (HBO) preconditioning can induce significant neuroprotection against acute neurological injury. We hypothesized that HBO preconditioning would prevent the development of postoperative cognitive impairment. Elderly male rats (20 months old) underwent stabilized tibial fracture operation under general anesthesia after HBO preconditioning (once a day for 5 days). Separate cohorts of animals were tested for cognitive function with fear conditioning and Y-maze tests, or euthanized at different times to assess the blood-brain barrier integrity, systemic and hippocampal proinflammatory cytokines, and caspase-3 activity. Animals exhibited significant cognitive impairment evidenced by a decreased percentage of freezing time and an increased number of learning trials on days 1, 3, and 7 after surgery, which were significantly prevented by HBO preconditioning. Furthermore, HBO preconditioning significantly ameliorated the increase in serum and hippocampal proinflammatory cytokines tumor necrosis factor-α, interleukin-1 ß (IL-1ß), IL-6, and high-mobility group protein 1 in surgery-challenged animals. Moreover, HBO preconditioning markedly improved blood-brain barrier integrity and caspase-3 activity in the hippocampus of surgery-challenged animals. These findings suggest that HBO preconditioning could significantly mitigate surgery-induced cognitive impairment, which is strongly associated with the reduction of systemic and hippocampal proinflammatory cytokines and caspase-3 activity.

[Improving effect of Shengjingsan on spermatogenic function following testicular torsion/detorsion in rats and its mechanism].

OBJECTIVE: To study the effect of Shengjingsan on spermatogenic function following testicular torsion/detorsion in rats and its action mechanism. METHODS: Forty SD male rats were equally randomized to groups A (sham operation), B (control), C (low-dose Shengjingsan), D (medium-dose Shengjingsan) and E (high-dose Shengjingsan). The model of testicular torsion was established by 720 degrees clockwise torsion of the left testis for 4 hours. An hour before operation, the rats of group B received daily gavage of normal saline at 1 ml per kg per d, while those in groups C, D and E that of Shengjingsan at 0.01, 0.02 and 0.03 g per kg per d, all for 35 days. Then all the rats were sacrificed for measuring the semen parameters by CASA and detecting the expression of the CatSper1 gene in the sperm by RT-PCR. RESULTS: Compared with group A, Sperm concentration, the percentage of grade a + b sperm, sperm vitality and CatSper1 expression were significantly lower in group B ([15.30 +/- 6.30] %, [44.42 +/- 6.36] %, [21.00 +/- 6.14] x 10(6)/ml and 1.12 +/- 0.50) than in A ([51.30 +/- 6.60]%, [69.01 +/- 7.20]%, [40.53 +/- 7.01] x 10(6)/ml and 2.04 +/- 0.77) (P < 0.01). Compared with group B, the four parameters were increased remarkably in groups D ([51.63 +/- 3.20] %, [72.09 +/- 2.20]%, [55.30 +/- 5.90] x10(6)/ml and 2.11 +/- 0.20) andE ([55.93 +/- 3.17]%, [73.01 +/- 2.11]%, [58.33 + 4.90] x 10(6)/ml and 2.31 +/- 0.17) (P < 0.01), but not significantly in C ([18.02 +/- 0.23]%, [48.04 +/- 7.01]%, [22.87 +/- 2.10] x 10(6)/ml and 1.19 +/- 0.51) (P > 0.05). CONCLUSION: Shengjingsan can improve sperm parameters following testicular torsion/ detorsion in male rats by regulating their spermatogenic function and improving the expression of CatSper1 in the sperm.

Hyperbaric oxygen preconditioning protects cortical neurons against oxygen-glucose deprivation injury: role of peroxisome proliferator-activated receptor-gamma.

Ischemic stroke is one of the leading causes of mortality and disability worldwide. Our previous studies have shown that hyperbaric oxygen (HBO) preconditioning can afford significant neuroprotection against cerebral ischemia-reperfusion (I/R) injury in rats. However, it is still unknown whether HBO preconditioning can directly protect primary cultured cortical neurons against oxygen-glucose deprivation (OGD). Peroxisome proliferator-activated receptor-gamma (PPAR γ) plays a central role in the regulation of apoptosis, oxidative stress and inflammation as well as affords significant neuroprotection against cerebral I/R injury. 15-deoxy-∆(12,14)-prostaglandin J(2) (15d-PGJ(2)) is an endogenous ligand with a high affinity for PPAR γ. Recently, some studies demonstrate that activation of PPAR γ mediates lipopolysaccharide and anesthetic preconditioning. In the present study, we firstly found that OGD exposure caused the significant damage of cultured cortical neurons evaluated by cell viability, lactate dehydrogenase (LDH) release and caspase-3 activity, which were significantly ameliorated by HBO preconditioning. Furthermore, HBO preconditioning significantly increased the levels of PPAR γ mRNA and protein, PPAR γ DNA binding activity, 15d-PGJ(2) and antioxidant enzymatic activities in primary cultured cortical neurons with OGD exposure. Moreover, PPAR γ antagonist GW9662 dose-dependently abolished the protection of HBO preconditioning in OGD-exposed neurons. GW9662 blocked the increase of PPAR γ DNA binding activity and antioxidant enzymatic activities, but did not influence the 15d-PGJ(2) level in OGD-exposed neurons with HBO preconditioning. However, the cyclooxygenase (COX)-2 inhibitor NS-398 blocked the production of 15d-PGJ(2) in OGD-exposed neurons with HBO preconditioning. In addition, 15d-PGJ(2) preconditioning could also protect cultured neurons against OGD injury. These results demonstrate that HBO preconditioning has directly beneficial effects on ODG-exposed cortical neurons by the activation of PPAR γ subsequent to the production of 15d-PGJ(2), which in turn increases the downstream antioxidant enzymatic activities.

Hydrogen gas improves survival rate and organ damage in zymosan-induced generalized inflammation model.

Sepsis/multiple organ dysfunction syndrome is the leading cause of death in critically ill patients. Recently, it has been suggested that hydrogen gas (H2) exerts a therapeutic antioxidant activity by selectively reducing hydroxyl radical (•OH, the most cytotoxic reactive oxygen species). We have found that H2 inhalation significantly improved the survival rate and organ damage of septic mice with moderate or severe cecal ligation and puncture. In the present study, we investigated the effects of 2% H2 treatment on survival rate and organ damage in zymosan (ZY)-induced generalized inflammation model. Here, we found that 2% H2 inhalation for 60 min starting at 1 and 6 h after ZY injection, respectively, significantly improved the 14-day survival rate of ZY-challenged mice from 10% to 70%. Furthermore, ZY-challenged mice showed significant multiple organ damage characterized by the increase in serum biochemical parameters (aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, and creatinine), as well as lung, liver, and kidney histopathological scores at 24 h after ZY injection, which was significantly attenuated by 2% H2 treatment. In addition, we found that the beneficial effects of H2 treatment on ZY-induced organ damage were associated with the decreased levels of oxidative product, increased activities of antioxidant enzyme, and reduced levels of early and late proinflammatory cytokines in serum and tissues. In conclusion, this study provides evidence that H2 treatment protects against multiple organ damages in ZY-induced generalized inflammation model, suggesting the potential use of H2 as a therapeutic agent in the therapy of conditions associated with inflammation-related multiple organ dysfunction syndrome.