Effect of trichostatin A on lipopolysaccharide-induced injury and apoptosis of human microvascular endothelial cell / 中国小儿急救医学

Objective:To investigate the effect of histone deacetylase inhibitor trichostatin A(TSA) on the lipopolysaccharide(LPS)-induced injury and apoptosis of human microvascular endothelial cell(HMEC).Methods:HMECs were used as research cells to establish LPS-induced septic cell model, which were divided into three groups according to different treatments: control group (150 μL of phosphate buffer), LPS group (150 μL of 5 μg/mL LPS), LPS+ TSA group (150 μL of 5 μg/mL LPS and 500 μg/L TSA). After cells of each group were cultured for 24 h and 48 h, the concentration of lactate dehydrogenase(LDH)in the culture supernatant was detected by enzyme-linked immunosorbent assay and the apoptosis rate of HMECs was detected by Annexin V-FTTC/PI staining, then comparison between different groups were made.Results:Compared with the control group, LDH concentration in LPS group increased significantly at 24 h[(4.67±1.27) ng/L vs. (11.57±0.83) ng/L ] and 48 h[(7.93±0.80) ng/L vs. (12.72±0.89) ng/L ]; Compared with LPS group, LDH concentration in LPS + TSA group decreased significantly at 24 h[(6.01±0.29) ng/L ] and 48 h[(5.96±0.27) ng/L ], and the differences were statistically significant ( P<0.05). Compared with the control group, the apoptosis rates of HMEC cells in LPS group were significantly higher at 24 h[(0.92±0.89)% vs. (1.66±0.09)% ] and 48 h[(1.09±0.14)% vs. (5.01±0.16)%]; Compared with LPS group, the apoptosis rate of HMEC cells in LPS + TSA group significantly decreased at 24 h[(1.36±0.01)% ] and 48 h[(4.19±0.23)% ], the differences were statistically significant ( P<0.05). Conclusion:TSA has the protective effect of reducing cell injury and apoptosis in sepsis.

Research on cellular damages and astrocyte activation after cerebral ischemia and reperfusion / 中国药理学通报

Aim To observe cellular damage and astrocyte activation at different time points of cerebral ischemia and reperfusion. Methods The middle cerebral artery of male SpragueDawley rats was occluded for 90 min followed by different time points of reperfusion. Eighty-five SPF male SD rats were randomly divided into control group (Sham), IR3, 6, 12, 24 and IR48h (MCAO followed by 48 h of reperfusion) group. Cerebral ischemia and reperfusion injury was observed by HE staining, and the structure of astrocytes was estimated with transmission electron microscopy (TEM). GFAP expression was detected by immunofluorescence staining and Western blot. Results Cerebral ischemia following by different time points of reperfusion led to different degrees of cellular damage, which was the most serious at 24 h of reperfusion. TEM showed destruction of astrocytes structure, swollen organelles and broken mitochondrial ridge. After cerebral ischemia-reperfusion, the expression levels of GFAP were significant up-regulated in the ischemic penumbra cortex and the highest was at 48 h of reperfusion, indicating astrocytes were activated. In addition, the results showed the gradual decrease in GFAP expression in the infarct core. Conclusions After cerebral ischemia-reperfusion, cellular damage is aggravated, and astrocytes are gradually activated in the ischemic penumbra. With the extension of reperfusion time, the boundaries of infarct area and ischemic area are gradually clear, and scarring may occur.

CdCl2 has zero-order kinetic cellular influx and induces cytotoxicity and genotoxicity at low concentrations in human leukocytes in vitro / El CdCl2 tiene un influjo celular cinético de orden cero e induce citotoxicidad y genotoxicidad a bajas concentraciones en leucocitos humanos in vitro

SUMMARY Cadmium (Cd2+) is a nonessential heavy metal that possesses a high capacity of bioaccumulation and exhibits toxic characteristics even at low concentrations. This study evaluated the genotoxicity and cytotoxicity in human leukocytes in vitro after exposure to a lower range of Cd2+concentration (1-25 (g/mL) using an unprecedented strategy by correlating between intracellular Cd2+ levels after exposure and cellular damage. Results demonstrated that Cd2+exposure from 5 to 25 fig/mL significantly increased the unviability of leukocytes, as well as the DNA damage, which was dose-dependent. The intracellular Cd2+ levels in leukocytes ranged from 9.85 to 94.38 pg/cell, and cytotoxicity and genotoxicity were induced at a concentration of24.22 pg/cell. The relationship between exposure concentration and intra-cellular Cd2+ levels suggests that its influx occurs in human leukocytes under zero-order kinetics.

RESUMEN El cadmio (Cd2+) es un metal pesado no esencial que posee una alta capacidad de bioacumulación y presenta características tóxicas incluso en bajas concentraciones. Este estudio evaluó la genotoxicidad y la citotoxicidad en leucocitos humanos in vitro después de la exposición a un rango inferior de concentración de Cd2+ (1-25 (g / mL) mediante una estrategia sin precedentes al correlacionar los niveles intracelulares de Cd2+ después de la exposición y el daño celular. Los resultados demostraron que la exposición a Cd2+ de 5 a 25 (g/mL aumentó significativamente la inviabilidad de los leucocitos, así como el daño en el ADN, que era dependiente de la dosis. Los niveles intracelulares de Cd2+ en leucocitos oscilaron entre 9,85 y 94,38 pg/célula, y se indujo la citotoxicidad y la genotoxicidad a una concentración de 24,22 pg/ célula. La relación entre la concentración de la exposición y los niveles intracelulares de Cd2+ sugiere que su influjo se produce en leucocitos humanos bajo una cinética de orden cero.

Histo-morphological Effects of Carica papaya on Cadmium Induced Prefrontal-Cortex Damage in Adult Wistar Rats

Background: This research investigated the recuperative (restorative) effect of aqueous extract of Carica papaya fruit on cadmium induced prefrontal-cortex damaged in adult Wistar rats (Rattus norvegicus). Previous research reports have confirmed that cadmium toxicity results in cellular damage which is due to an increase in production of reactive oxygen species and prevention of the activities of antioxidant enzymes. Various parts of the brain (prefrontal cortex, hippocampus and so on) are majorly affected by cadmium as its induced damage. Methods: 30 Wistar rats (70 g-190 g) were used for this research. The rats were randomly selected into six groups of five animals each. A single dose of 3CdSO4.8H2O (Cadmium sulphate octahydrous) 3.5 mg/kg body weights was administered intraperitoneally to three of these groups against control a group that was not exposed to Cadmium. Two groups were treated with different doses of Carica papaya fruit extract for the period of four weeks. After four weeks, the rats were sacrificed and organs excised, weigh and fixed in fixative for histological processing. The photomicrographs of the normal control, induced control and treated groups were observed and compared for histomorphological similarities and differences. Results: Cadmium was observed to have caused a distortion, disruption and calcification in the cells and tissue of the prefrontal cortex. There was shrinkage of nuclei of the neurons in cadmium induced rats. It was also observed that cadmium caused a loss in function of cell in the process of protein biosynthesis. The morphology of the neuronal cells of rats treated with high and low doses of Carica papaya extract was found to be slightly normal with increased viable neuronal cells as compared with the neurons of the normal control group 1 animals, though the restorative effects of the high dose treated rats were more pronounced. Also, it was observed that the damage to the brain section neurons treated with vitamins C and E before induction was not pronounced. Moreso, loss in body weight were observed in cadmium induced group animals and over treatment with Carica papaya, gain in the rats body weight was observed in the treatment animal groups as compared with the body weight of rats in normal control. Animal body weight before cadmium inoculation, after inoculation and before animal sacrifice were compared across all the groups and it was found that, there was a progressive increase in rats body weight (99±2,35≤ 150 ±3.21), (120±2.32≤189±3.21) and (135±1.35≤175±2.15) respectively which was significant at P ≤ 0.05. Conclusion: It can be ascertained from this present study that Carica papaya has ameliorative properties against deleterious effects of cadmium on the neurons and neuroglia of the prefrontal-cortex in Wistar rats which is dose dependent.

Effects of miR-7-5p on TK6 cell damage induced by hydroquinone / 中国职业医学

OBJECTIVE: To investigate the mechanism of miR-7-5p in TK6 cell damage induced by hydroquinone( HQ) by constructing stable miR-7-5p over-expressing human lymphoblastoid TK6 cell line using lentivirus. METHODS: i) The miR-7-5p over-expression lentivirus vectors were constructed,and then infected to TK6 cells. The miR-7-5p overexpression stable TK6 cell line( TK6-miR-7-5p cells) and negative control cells( TK6-NC cells) were selected with puromycin. The infection efficiency was confirmed by real-time fluorescent quantitative polymerase chain reaction assay.ii) TK6,TK6-NC and TK6-miR-7-5p cells were treated with HQ at final concentrations of 0 and 40 μmol/L for 48 hours.Cell viability was determined by CCK-8 assay. The early apoptosis rate of cells was detected by flow cytometry. The relative expression of poly( ADP-ribose) polymerase-1( PARP-1) and breast cancer susceptibility gene 1( BRCA1) proteins in 3 kinds of cells treated with HQ at the final concentration of 40 μmol/L was detected by Western blotting. RESULTS: i) The TK6 cell line with stable expression of miR-7-5p were successfully screened. Compared with normal TK6 cells,the relative expression of miR-7-5p in TK6-miR-7-5p cells increased by about 17 times( P < 0. 01) with no significant changes in cell morphology. ii) After treatment with 40 μmol/L HQ,the survival rate of TK6-miR-7-5p cells decreased compared with normal TK6 cells and TK6-NC cells( P < 0. 01),early apoptosis rate increased( P < 0. 01),the relative expression of PARP-1 and BRCA1 protein was decreased( P < 0. 05). CONCLUSION: MiR-7-5p may lead to the increase of early apoptosis in TK6 cells induced by HQ through inhibiting the DNA damage repair capacity related to PARP-1 and BRCA1.

Mitochondrial and DNA damage in bovine somatic cell nuclear transfer embryos

The generation of reactive oxygen species (ROS) and subsequent mitochondrial and DNA damage in bovine somatic cell nuclear transfer (SCNT) embryos were examined. Bovine enucleated oocytes were electrofused with donor cells and then activated by a combination of Ca-ionophore and 6-dimethylaminopurine culture. The H2O2 and .OH radical levels, mitochondrial morphology and membrane potential (DeltaPsi), and DNA fragmentation of SCNT and in vitro fertilized (IVF) embryos at the zygote stage were analyzed. The H2O2 (35.6 +/- 1.1 pixels/embryo) and .OH radical levels (44.6 +/- 1.2 pixels/embryo) of SCNT embryos were significantly higher than those of IVF embryos (19.2 +/- 1.5 and 23.8 +/- 1.8 pixels/embryo, respectively, p < 0.05). The mitochondria morphology of SCNT embryos was diffused within the cytoplasm. The DeltaPsi of SCNT embryos was significantly lower (p < 0.05) than that of IVF embryos (0.95 +/- 0.04 vs. 1.21 +/- 0.06, red/green). Moreover, the comet tail length of SCNT embryos was longer than that of IVF embryos (515.5 +/- 26.4 microm vs. 425.6 +/- 25.0 microm, p < 0.05). These results indicate that mitochondrial and DNA damage increased in bovine SCNT embryos, which may have been induced by increased ROS levels.

Investigation on the cellular damage of hippocampus neuron in a rat model of chronic cerebral hypoperfusion / 中华行为医学与脑科学杂志

Objective To explore the the cellular damage of hippocampus neuron in a rat model of chronic cerebral hypoperfusion. Methods Rat model of chronic cerebral hypoperfusion was established by permanent bilateral common carotid arteries occlusion (2VO). Eight weeks after the operation,the brains were removed and examined with histological stains, electron microscope, flow cytometer and Western Blotting. Results Compared with the control group,the arrangement of hippocampus neurons in 2VO rats appeared to be more irregular, and the number of the neurons decreased partly ( CA2: ( 34.75 ± 3.40) vs (49.25 ± 9.67 ), P ＜ 0. 05; DG: ( 73.50 ± 9.26)vs ( 90.75 ± 4.35 ), P ＜ 0. 05 ). By electron microscopic study of hippocampus neurons in 2VO rats, the nuclei became smaller and the heterochromatin assembled in the border of the nuclei in some neurons, while cytoplasm swelled,especially in mitochondria and endoplasmic reticulum. The rate of apoptosis of hippocampus neurons in 2VO rats( (9. 117 ±2. 540)% ) ,detected by the flow cytometer,was higher than that of sham group( (4. 750 ±3.481 ) % ) (P ＜ 0. 05 ). The expression of pro-caspase-3 in hippocampus of 2 VO rats was not altered significantly compared with the control group(P ＞ 0. 05 ). Conclusion The cellular damage of hippocampus neuron in 2VO rats was mainly caused by apoptosis.

Nitric oxide is not involved in Neisseria gonorrhoeae-induced cellular damage of human Fallopian tubes in vitro

In the present study, we investigated whether cellular damage, as demonstrated by lactate dehydrogenase (LDH) release in the human fallopian tube (FT) infected by Neisseria gonorrhoeae (Ngo), correlated with high levels of nitric oxide synthase (NOS) mRNA and enzyme activity. Infection with Ngo induced a significant increase (~35-fold) in mRNA transcripts of the inducible isoform of NOS. Paradoxically, a reduction in NOS enzyme activity was observed in infected cultures, suggesting that gonococcal infection possibly influences translation of iNOS mRNA to the enzyme. In addition, treatment with the NOS inhibitor TRIM did not prevent gonococcal-induced cellular damage. In contrast, the addition of the inhibitor L-NAME induced a 40 percent reduction in LDH release, which correlated with a ~50 percent reduction in gonococcal numbers. Moreover, treatment of normal FT explants with an exogenous NO donor, SNAP, did not induce significant cellular damage. Taken together, our data suggest that NO does not contribute to cellular damage during infection of the human FT with Neisseria gonorrhoeae.

Mecanismos del dano celular en la insuficiencia renal aguda / Mechanisms of cell damage in acute renal failure

Los mecanismos del dano celular en la insuficiencia renal aguda incluyen alteraciones en la produccion de energia, la permeabilidad celular y el transporte de calcio. Dichas alteraciones producen cambios progresivos en la estructura celular que pueden ser reversibles si desaparece la causa que llevo a la falla renal, excepto cuando se alcanza la fase final de la lesion de la membrana y se llega a necrosis celular. Este mismo fenomeno probablemente ocurre tambien en situaciones clinicas.

The mechanisms of cellular damage in acute renal failure Include alterations in energy production, cell membrane permeability and calcium transport. These changes lead to progressive damage of the whole cellular structure which In general can be reversible if the precipitating cause disappears, except when the final stages of cell membrane lesion take place and cellular necrosis has occurred. This phenomenon probably applies for the clinical settling as well