mDia1 Research Articles

Effects of hydrogen on expression of ROCK1 and mDia1 in intestinal tissues of septic mice

Objective To evaluate the effects of hydrogen on the expression of Rho-associated protein kinase 1(ROCK1)and mammalian diaphanous-related formin 1(mDia1)in intestinal tissues of septic mice. Methods Ninety male C57BL/6 mice, weighing 20-25 g, aged 6 weeks, were divided into 3 groups(n=30 each)using a random number table: control group(group C), sepsis group(group S)and sepsis plus hydrogen group(group SH). Sepsis was produced by cecal ligation and puncture(CLP). Group SH inhaled 2% hydrogen for 1 h starting from 1 and 6 h after CLP.Twenty mice in each group were selected and observed for 7-day survival rate.Ten mice in each group were sacrificed at 24 h after CLP, and blood samples were obtained from hearts to measure the activity of serum diamine oxidase(DAO)and to count the colony-forming units after bacterial culture.The small intestinal samples were obtained for microscopic examination of pathological changes and for determination of ROCK1 and mDia1 positive cell rates(using immunohistochemical staining)and expression of intestinal epithelial junctional protein E-cadherin(by immunofluorescent staining). Intestinal damage was assessed and scored.The ratio of ROCK1 to mDia1 positive cell rates(ROCK1/mDia1 ratio)was calculated. Results Compared with group C, the survival rate was significantly decreased, the serum DAO activity, colony counts and intestinal damage scores were increased, ROCK1 and mDia1 positive cell rates were increased, and the expression of E-cadherin was down-regulated in S and SH groups, ROCK1/mDia1 ratio was increased in group S(P 0.05). Compared with group S, the survival rate was significantly increased, the serum DAO activity, colony counts and intestinal damage scores were decreased, the ROCK1 positive cell rate was decreased, the mDia1 positive cell rate was increased, ROCK1/mDia1 ratio was decreased, and the expression of E-cadherin was up-regulated in group SH(P<0.05). Conclusion The mechanism by which hydrogen improves intestinal barrier function may be related to down-regulation of ROCK1 expression, up-regulation of mDia1 expression and correction of the imbalance in ROCK1/mDia1 ratio in intestinal tissues of septic mice. Key words: Hydrogen; Sepsis; rho-associated kinases; rhoA GTP-binding protein; Intestinal mucosa

RhoA/mDia1 pathway involved in the expression of p-ERM in the pulmonary micro-vascular endothelial cell induced by lipopolysaccharide

Objective To investigate the possibility of the involvement of RhoA/mDia1 pathway to cause the expression of phosphorylate ezrin-radixin-moesin (p-ERM) in rat pulmonary micro-vascular endothelial cell (PMVEC) after the stimulation of lipopolysaccharide (LPS). Methods The specimens of lung tissue were taken from healthy male SPF grade SD rat with 100-120 g body weight which was purchased from the laboratory animal center of Anhui province. After culture, the PMVECs were randomly divided into dose-dependent groups (0, 0.1, 1, 10 μg/mL LPS added in PMVECs and cultured for 30 min, n=8 in each), time-dependent groups (10 μg/mL LPS added to PMVECs cultured for 0, 15, 30, 60, 120 min, n=8 in each) and intervention group (n=8). In the intervention group, PMVECs were cultured with 1 μg/mL C3 transferase in serum free media for 240 min, followed by treatment with 10 μg/mL LPS for 30 min. Meanwhile, two control groups in serum-free DMEM medium were made by adding 10 μg/mL LPS to PMVECs and 1 μg/mL C3 transferase to PMVECs respectively cultured for 30 min (n=8 in each). Western blot was used to detect the level of p-ERM, ERM and mDia1. Data were analyzed with SPSS 16.0 software, while one way analysis of variance (ANOVA) was used to compare multiple sets of variables, the intergroup comparisons were analyzed by the least-significant-difference (LSD) tests, with P<0.05 for the statistically significant difference. Results ERM, p-ERM and mDia1 were presented in rat PMVEC. Stimulation with LPS up-regulated p-ERM, mDia1 in a dose-dependent manner: LPS [0 μg/mL LPS group: (0.520±0.101), 0.1 μg/mL LPS group: (0.657±0.092), 1 μg/mL LPS group: (0.891±0.167), 10 μg/mL LPS group: (1.227±0.106); 0 μg/mL group vs. 0.1 μg/mL group, P>0.05; the rest P 0.05; the rest P 0.05; the rest P<0.05); and the level of mDia1 increased at 15 min(0.779±0.035), peaked at 30 min(0.889±0.036)then decreased at 60 min (0.648±0.019), 90 min (0.582±0.068), but kept at higher level at 120 min (0.526±0.059) than that in control group(0.284±0.118, all P<0.01). C3 transferase caused a marked attenuation of LPS induced p-ERM expression [control group: (0.339±0.069); C3+ LPS group: (0.438±0.07); C3 control group: (0.352±0.071); LPS control group: (0.634±0.191), C3+ LPS group vs. LPS control group, P=0.01], as the same in mDia1[control group: (0.449±0.122); C3+ LPS group: (0.380±0.148); C3 control group: (0.404±0.164); LPS control group: (0.622±0.174), C3+ LPS group vs. LPS control group, P<0.01]. Conclusions LPS could up-regulated the expression of p-ERM protein, and inhibition of RhoA/mDia1 signal pathway by C3 transferase could down-regulated the p-ERM levels. Key words: Lipopolysaccharide; Pulmonary microvascular endothelial cell; Ezrin-Radixin-Moesin; Inflammation; Acute respiratory distress syndrome; RhoA/mDia1

Audio-Kinetic Art: The Construction and Operation of my 'Laser-chromasonic Tower'

sound equipment and laser and incandescent light image-producing equipment, 11 m high, 6.4 m dia. of base, 1975. (Civic Square, Canberra, Australia.) (Fig. 3, cf. page 51.) Top right: Madhoor Kapur. 'Maya, No. 25', oil on canvas, 61 x 61 cm, 1974. (Fig. 4, cf. page 13.) Bottom left: Rita Deanin Abbey. Untitled mural, acrylic paint on canvas, 3 x 9 m, 1973-74. (Judy Bayley Theater, University of Nevada, Las Vegas, Nevada, U.S.A.) (Photo: T. Whitmayer, Boulder City, Nevada.) (Fig. 2, cf. page 32.)

Physiological genomics in PG and beyond: October to December 2005

physiological genomics ( PG ) publishes, on a quarterly basis, brief editorial perspectives entitled “Physiological genomics in PG and beyond.” These editorial perspectives provide brief, accessible highlights of the studies published in PG in the most recent quarter, and relate those studies to