Effects of Propofol on The mRNA Expression of Toll-like Receptor 4 in BV-2 Cells During Mimic Ischemia-Reperfusion Injury In Vitro

This study investigated the effects of propofol on the mRNA expression of Toll-like receptor-4 （TLR4） in BV-2 cells during mimic ischemia-reperfusion （I/R） injury in vitro. BV-2 cells, a mouse microglia line, were cultured and divided into 4 groups at random： control group （group C）, ischemia/reperfusion group （group I/R）, low-dose propofol （25 μmol/L） intervention group （group PF25） and high-dose propofol （100 μmol/L） intervention group （group PF100）. The mRNA expression of TLR4 and NF-κB was measured by means of RT-PCR. TNF-α levels in the supernatants of BV-2 cells were detected by ELISA. The results showed that the mRNA expression of TLR4 and NF-κB was significantly higher in groups I/R, PF25 and PF100 than in group C （P〈0.01）. And the TNF-α level in the supernatants was elevated in groups I/R, PF25 and PF100 as compared with that in group C （P〈0.01）. After pre-treatment with propofol, the mRNA expressions of TLR4 and NF-κB and the TNF-α level were significantly decreased in groups PF25 and PF100 in comparison to those in group I/R （P〈0.01）. And the decrease in those indicators was more significant in group PF100 than in group PF25 （P〈0.01）. It was concluded that propofol exerted brain-protecting effects during I/R injury by suppressing the mRNA expressions of TLR4 and NF-κB and deceasing the TNF-α level.

Impact of Toll-like Receptor 4 Deficiency on Cerebrocardiac Syndrome

In order to investigate the role of Toll-like receptor 4 （TLR4） in cerebrocardiac syndrome （CCS）, the partial cerebral ischemia/reperfusion （I/R） models in mice with different TLR4 genotypes were established in the present study. TLR4 wild-type （C3H/HeN） and mutant （C3H/HeJ） mice of 6-8 weeks of age were divided into 4 groups at random： C3H/HeN sham group （n=10）, C3H/HeJ sham group （n=10）, C3H/HeN model group （n=10） and C3H/HeJ model group （n=10）. Partial cerebral I/R was caused by the middle cerebral artery occlusion （MCAO） to duplicate CCS models in mice. After the operation, the electrocardiogram （ECG）, the level of tumor necrosis factor-alpha （TNF-c0 in myocardial tissue and the cardiac pathological changes were observed in each group. It was shown that the brain infarct volume in C3H/HeN model group was larger than that in C3H/HeJ model group （P〈0.01）. The ST segment change and T wave inversion occurred frequently in model groups. Moreover, the TNF-ct level in C3H/HeN model group was higher than that in C3H/HeJ model group （P〈0.01）. The myocar- dial injury was aggravated in C3H/HeN group as compared with C3H/HeJ group. It was concluded that TLR4 was implicated in the development of CCS.

Apoptosis of Human Trabecular Meshwork Cells Induced by Transforming Growth Factor-β_2 in vitro

Whether transforming growth factor β 2 (TGF β 2) induces apoptosis of human trabecular meshwork cells was investigated in vitro . Cultured 3 5 passage human trabecular meshwork cells were treated with 0 (control), 0.32, 1, 3.2 ng/ml TGF β 2 for 48 h and divided into control group and experimental group. The apoptosis of human trabecular meshwork cells was examined by transmisson electron microscopy, TUNEL technique and flow cytometry. The results showed characteristic morphologic changes of apoptotic cells were observed under transmission electron microscopy. DNA fragmentation of human trabecular meshwork cells was found by TUNEL technique. Quantitative analysis of flow cytometry showed that percentages of apoptotic human trabecular meshwork cells were (2.79±0.44) %, (4.43 ±1.17) % and (9.60±2.05) % respectively with different concentrations [1 ng/ml ( P< 0.05), 3.2 ng/ml ( P< 0.01)] of TGF β 2 with the difference being significant between experimental group and control group[(1.41±0.34) %]. It was concluded that TGF β 2 can induce apoptosis of human trabecular meshwork cells in vitro and may be involved in the decrease of trabecular meshwork cells in the patients with primary open angle glaucoma and aging of normal people.

The effect of root of rhododendron on the activation of NF-κB in a chronic glomerulonephritis rat model

Objective： We have explored the role of nuclear factor kappa B（NF-κB） in the pathogenesis of chronic glomemlonephritis, and investigated the effect of rhododendron root on the activation of NF-κB. Methods： Thirty-six Wistar rats were randomly divided into three groups： a control group, a glomerulonephritis model group and a therapy group（glomerulonephritis animals treated with the root of rhododendron）. Bovine serum albumin（BSA） nephritis was induced by subcutaneous immunization and daily intraperitoneal administration of BSA. Twenty-four-hour urinary protein and serum creatinine values were measured, and renal pathology was assessed histologically by optical microscopy and electron microscopy. NF-κB activity was determined by an electrophoretic mobility shift assay（EMSA）. Results：Compared with the control rats, glomerulonephritis model rats exhibited a significant increase in both 24 h urinary protein and serum creatinine, and had abnormal renal histology. The administration of the root of rhododendron ameliorated these changes. NF-κB activity in glomerulonephritis model group was greater than that in rhododendron-treated group, and NF-κB activity was greater in both glomerulonephritis groups than in the control group（P 〈 0.01）. Conclusion：These observations suggest that NF-κB plays a role in the pathogenesis of chronic glomemlonephritis, and rhododendron root may attenuate renal damages by downregulating the activation of NF- κB in this model.

Antagonistic Effects of Tranilast on Proliferation and Collagen Synthesis Induced by TGF-β_2 in Cultured Human Trabecular Meshwork Cells

Whether tranilast had antagonistic effect on proliferation inhibition and collagen synthesis promotion induced by TGF-β 2 in cultured human trabecular meshwork cells was investigated. Suspension of 1×104 cultured human trabecular meshwork cells of 3—5 passage was distributed in each well of a 96-well disk and divided into control group and experimental group. After 24 h, 0 μg/ml (control), 12.5 μg/ml, 25 μg/ml, 50 μg/ml tranilast with 3.2 ng/ml TGF-β 2 were added into the incubation medium. Another 24 h later, proliferation and collagen synthesis in cultured human trabecular meshwork cells were examined respectively by using tetrazolium-based semiautomated colormetric (MTT) assay and 3H-proline incorporation with liquid scintillation technique. The results showed absorbance (A) values of the experimental groups were 0.9036±0.3017, 1.1361± 0.1352, 1.2457±0.1524 according to the different concentrations of tranilast, and 0.8956± 0.1903 of the control group. In comparison with the control group, 25 μg/ml (q'=3.23, P< 0.05), 50 μg/ml (q'=4.70, P<0.01) tranilast significantly antagonized the decrease of the A values induced by TGF-β 2 in the cultured human trabecular meshwork cells. In comparison with the control group [817.37±124.21 cpm/104 cells], 12.5 μg/ml (620.33±80.46 cpm/104 cells, q'= 4.26, P< 0.05), 25 μg/ml (594.58±88.13 cpm/104 cells, q'=4.81, P<0.01), 50 μg/ml (418.64±67.90 cpm/104 cells, q'=8.62, P<0.01) tranilast significantly inhibited the incorporation of 3H-proline into the cultured human trabecular meshwork cells promoted by TGF-β 2 in a dose-dependent manner. It was concluded that tranilast had the antagonistic effect on the proliferation inhibition and collagen synthesis promotion induced by TGF-β 2 in the cultured human trabecular meshwork cells.

Correlating interleukin-10 promoter gene polymorphisms with human cerebral infarction onset

Evidence suggests that interleukin-10（IL-10） deficiency exacerbates inflammation and worsens the outcome of brain ischemia. In view of the critical role of the single nucleotide polymorphic sites-1082（A/G） and-819（C/T） in the promoter region of the IL-10 gene, we hypothesized that they are associated with cerebral infarction morbidity in the Chinese Han population. We genotyped these allelic gene polymorphisms by amplification refractory mutation system-polymerase chain reaction methods in 181 patients with cerebral infarction（cerebral infarction group） and 115 healthy subjects（control group）. We identified significant differences in genotype distribution and allele frequency of the IL-10-1082 A/G allele between cerebral infarction and control groups（χ2 = 6.643, P = 0.010）. The IL-10-1082 A allele frequency was significantly higher in the cerebral infarction group（92.3%） than in the control group（86.1%）（P = 0.015）. Moreover, cerebral infarction risk of the AA genotype was 2-fold higher than with the AG genotype（OR = 2.031, 95%CI： 1.134-3.637）. In addition, AA genotype together with hypertension was the independent risk factor of cerebral infarction（OR = 2.073, 95%CI： 1.278-3.364）. No statistical difference in genotype distribution or allele frequency of IL-10-819 C/T was found between cerebral infarction and control groups（P 〉 0.05）. These findings suggest that the IL-10-1082 A/G gene polymorphism is involved in cerebral infarction, and increased A allele frequency is closely associated with occurrence of cerebral infarction.

Minocycline Attenuates Microglial Response and Reduces Neuronal Death after Cardiac Arrest and Cardiopulmonary Resuscitation in Mice

The possible role of minocycline in microglial activation and neuronal death after cardiac arrest（CA） and cardiopulmonary resuscitation（CPR） in mice was investigated in this study. The mice were given potassium chloride to stop the heart beating for 8 min to achieve CA, and they were subsequently resuscitated with epinephrine and chest compressions. Forty adult C57BL/6 male mice were divided into 4 groups（n=10 each）： sham-operated group, CA/CPR group, CA/CPR＋minocycline group, and CA/CPR＋vehicle group. Animals in the latter two groups were intraperitoneally injected with minocycline（50 mg/kg） or vehicle（normal saline） 30 min after recovery of spontaneous circulation（ROSC）. Twenty-four h after CA/CPR, the brains were removed for histological evaluation of the hippocampus. Microglial activation was evaluated by detecting the expression of ionized calcium-binding adapter molecule-1（Iba1） by immunohistochemistry. Neuronal death was analyzed by hematoxylin and eosin（H＆E） staining and the levels of tumor necrosis factor-alpha（TNF-α） in the hippocampus were measured by enzyme-linked immunosorbent assay（ELISA）. The results showed that the neuronal death was aggravated, most microglia were activated and TNF-α levels were enhanced in the hippocampus CA1 region of mice subjected to CA/CPR as compared with those in the sham-operated group（P〈0.05）. Administration with minocycline 30 min after ROSC could significantly decrease the microglial response, TNF-α levels and neuronal death（P〈0.05）. It was concluded that early administration with minocycline has a strong therapeutic potential for CA/CPR-induced brain injury.

Improved Survival and Neurological Outcomes after Cardiopulmonary Resuscitation in Toll-like Receptor 4-mutant Mice

Background：Toll-like receptor 4 （TLR4） is a crucial receptor in the innate immune system and noninfectious immune responses.It has been reported that TLR4 participates in the pathological course of ischemia/reperfusion （I/R） injury.However,the role of TLR4 in the process of I/R injury after cardiac arrest （CA） and cardiopulmonary resuscitation （CPR） is still unknown.In this study,we investigated the effects of TLR4 mutation on survival and neurological outcome in a mouse model of CA/CPR.Methods：A model of potassium-induced CA was performed on TLR4-mutant mice （C3H/HeJ） and wild-type mice （C3H/HeN）.After 3 min of untreated CA,resuscitation was attempted with chest compression,ventilation,and intravenous epinephrine.Behavioral tests were performed on mice on day 3 after CPR.The morphological changes in hippocampal neurons were assessed by light and electron microscopy.Expressions of TLR4 and intercellular adhesion molecule-1 （ICAM-l） were detected by Western blot.Levels of tumor necrosis factor-α （TNF-α） and myeloperoxidase （MPO） were measured with enzyme-linked immunosorbent assay （ELISA）.Results：On day 3 after resuscitation the overall mortality was 33.33％ in C3H/HeJ group compared with 53.33％ in C3H/HeN group （P ＜ 0.05）.And there was much higher central tendency in C3H/HeJ group than C3H/HeN group during open field test （P ＜ 0.05）.Meanwhile,the percentage of nonviable neurons was 2 1.16％ in C3 H/HeJ group compared with 53.11％ in C3H/HeN group （P ＜ 0.05）.And there were significantly lower levels ofhippocampal TNF-α and MPO in C3H/HeJ mice （TNF-α：6.85±1.19 ng/mL,MPO：0.33±0.11 U/g） than C3 H/HeN mice （TNF-α：11.36±2.12 ng/mL,MPO：0.54±0.17 U/g） （all P ＜ 0.01）.CPR also significantly increased the expressions of TLR4 and ICAM-1 in C3H/HeN group.However,the expression ofICAM-l was much lower in C3H/HeJ group than in C3H/HeN group after CPR （P ＜ 0.01）.Conclusion：TLR4 signaling is involved in brain damage and in inflammation triggered by CA/CPR.