OBJECTIVEEndotoxemia is a serious syndrome resulting in multi-organ failure. Once it happens, the penetration of small intestine epithelium increases, body liquid losses, then effective circulating blood decreases and serious metabolic acidosis, serious hypotension, systolic failure, and even shock may occur. In this pathological process, endotoxin, tumor necrosis alpha and systolic dysfunction play important roles. Nowadays, many studies have been done to resolve the systolic dysfunction, but too much attention had been paid to the followings: the depressions of myocardium caused by tumor necrosis alpha, other inflammatory factors, endotoxin and metabolic acidosis; the disturbance of blood vessel-nerve regulations; nitric oxide (NO)/inducible nitric oxide synthase (iNOS) over-synthesis and the decreased density of beta-receptors in the myocardium and/or their activities. Little attention has been paid to the relationship between alpha sarcmeric actin (alpha-SA) and systolic dysfunction during endotoxemia. Glutamine (Gln) can be metabolized into glutathione, an eliminator of free radical. It has been used in preventing myocardial damage from reperfusion. This study aimed to observe the dynamic changes of alpha-SA and mRNA expressions in rats with endotoxemia and examine the effects of Gln on them.

METHODSClassical rat model of endotoxemia was established by intraperitoneal injection of LPS (4 mg/kg, Escherichia coli O55:B5, Sigma). 121 Wistar 18-day-rats were divided into three groups randomly, (1) 0 h control group (normal saline: 1 ml/kg, n = 11). (2) LPS group (LPS: 4 mg/kg, n = 55). (3) Gln group (LPS: 4 mg/kg and immediately 13.64%; Gln: 1 ml/kg, Fresenus, n = 55), Furthermore, LPS and Gln groups were divided into 2, 4, 6, 24 and 72 h time points (n = 11). Each time point of LPS and Gln as well as control rats were anaesthetized at each time point with 1% chloral hydrate injected intraperitoneally at the dosage of 1 ml/kg. Then rats were sacrificed at appoint time, and the hearts were isolated. Eight of them were put in 76 degrees C liquid nitrogen and then frozen in minute 80 degrees C icebox in order to measure the expression of alpha-SA mRNA by RT-PCR. Three of them were fixed in 4% formaldehydum polymerisatum for 12 to 16 h, then the expression of alpha-SA was detected by immunohistochemistry.

RESULTS(1) Compared to 0 h, the expressions of alpha-SA and mRNA in LPS group were significantly depressed (P < 0.01). In LPS group, the lowest was at 6 - 24 h, while in Gln group, it was postponed to 24 h. At 72 h, there was no difference in expressions of alpha-SA between Gln and 0 h group (P > 0.05). (2) Comparing at same time point, the expressions of alpha-SA were significant higher in Gln group than those in LPS group, while the expressions of alpha-SA mRNA in Gln group were high at 4-72 h. There was, however, no significant difference at early phase (P > 0.05).

CONCLUSIONAlpha-SA and its mRNA expression were depressed in LPS-induced endotoxemia, especially from 6 to 24 h. It could damage the systolic function. alpha-SA decrease in endotoxemia was due to the inhibited synthesis other than the promoted degradation. Glutamine could inhibit the effects of LPS on both alpha-SA and its mRNA expressions.

Actins ; metabolism ; Animals ; Endotoxemia ; metabolism ; Glutamine ; pharmacology ; Lipopolysaccharides ; Myocardium ; metabolism ; RNA, Messenger ; metabolism ; Rats ; Rats, Wistar

It is believed that there exists some relationship between the distribution and morphology of intracellular actin and cell adherence. Cells are likely to be deteched when the quantity of actin filament decreases. Actin filaments locate in the fringe of cancer cells and cells cultured in static state, so that these filaments can stretch out and form pseudopodia to adhere to the matrix. When these cells are stimulated their pseudopodia retract so that they can easily be detached from the matrix. When external forces are exerted on cells to adhere and deadhere from the matrix, the morphology and distribution of skeleton actin will change, so as the cells' morphology. The skeleton actins in cells are changed differently to adapt to different external forces which are imposed on the cells. It is obvious that the relationship between the mechanism of cell adhering to the matrix and the morphology & distribution of actins needs more attention.
Actin Cytoskeleton ; metabolism ; Actins ; metabolism ; Cell Adhesion ; Humans ; Neoplasms ; metabolism ; pathology ; Pseudopodia ; metabolism ; Shear Strength

Epilepsy is a common, chronic neurological disorder that has been associated with impaired neurodevelopment and immunity. The chemokine receptor CXCR5 is involved in seizures via an unknown mechanism. Here, we first determined the expression pattern and distribution of the CXCR5 gene in the mouse brain during different stages of development and the brain tissue of patients with epilepsy. Subsequently, we found that the knockdown of CXCR5 increased the susceptibility of mice to pentylenetetrazol- and kainic acid-induced seizures, whereas CXCR5 overexpression had the opposite effect. CXCR5 knockdown in mouse embryos via viral vector electrotransfer negatively influenced the motility and multipolar-to-bipolar transition of migratory neurons. Using a human-derived induced an in vitro multipotential stem cell neurodevelopmental model, we determined that CXCR5 regulates neuronal migration and polarization by stabilizing the actin cytoskeleton during various stages of neurodevelopment. Electrophysiological experiments demonstrated that the knockdown of CXCR5 induced neuronal hyperexcitability, resulting in an increased number of seizures. Finally, our results suggested that CXCR5 deficiency triggers seizure-related electrical activity through a previously unknown mechanism, namely, the disruption of neuronal polarity.
Animals ; Humans ; Mice ; Actin Cytoskeleton/metabolism* ; Actins/metabolism* ; Epilepsy/metabolism* ; Neurons/metabolism* ; Receptors, CXCR5/metabolism* ; Seizures/metabolism*

This study aimed to investigate the effects of nanoparticles PLGA-NPs and mesoporous silicon nanoparticles(MSNs) of different stiffness before and after combination with menthol or curcumol on the mechanical properties of bEnd.3 cells. The particle size distributions of PLGA-NPs and MSNs were measured by Malvern particle size analyzer, and the stiffness of the two nanoparticles was quantified by atomic force microscopy(AFM). The bEnd.3 cells were cultured in vitro, and the cell surface morphology, roughness, and Young's modulus were examined to characterize the roughness and stiffness of the cell surface. The changes in the mechanical properties of the cells were observed by AFM, and the structure and expression of cytoskeletal F-actin were observed by a laser-scanning confocal microscope. The results showed that both nanoparticles had good dispersion. The particle size of PLGA-NPs was(98.77±2.04) nm, the PDI was(0.140±0.030), and Young's modulus value was(104.717±8.475) MPa. The particle size of MSNs was(97.47±3.92) nm, the PDI was(0.380±0.016), and Young's modulus value was(306.019±8.822) MPa. The stiffness of PLGA-NPs was significantly lower than that of MSNs. After bEnd.3 cells were treated by PLGA-NPs and MSNs separately, the cells showed fine pores on the cell surface, increased roughness, decreased Young's modulus, blurred and broken F-actin bands, and reduced mean gray value. Compared with PLGA-NPs alone, PLGA-NPs combined with menthol or curcumol could allow deepened and densely distributed surface pores of bEnd.3 cells, increase roughness, reduce Young's modulus, aggravate F-actin band breakage, and diminish mean gray value. Compared with MSNs alone, MSNs combined with menthol could allow deepened and densely distributed surface pores of bEnd.3 cells, increase roughness, reduce Young's modulus, aggravate F-actin band breakage, and diminish mean gray value, while no significant difference was observed in combination with curcumol. Therefore, it is inferred that the aromatic components can increase the intracellular uptake and transport of nanoparticles by altering the biomechanical properties of bEnd.3 cells.
Animals ; Mice ; Menthol/pharmacology* ; Actins/metabolism* ; Endothelial Cells/metabolism* ; Nanoparticles/chemistry*

Actins ; metabolism ; Adult ; Glomus Tumor ; metabolism ; pathology ; surgery ; Humans ; Male ; Trachea ; pathology ; Tracheal Neoplasms ; metabolism ; pathology ; surgery ; Tracheotomy ; Vimentin ; metabolism

Actins ; metabolism ; Female ; Glomus Tumor ; metabolism ; pathology ; surgery ; Humans ; Skin Neoplasms ; metabolism ; pathology ; surgery ; Thigh ; Vimentin ; metabolism ; Young Adult

Actins ; metabolism ; Female ; Fibroma ; metabolism ; pathology ; surgery ; Foot Diseases ; metabolism ; pathology ; Humans ; Immunohistochemistry ; Inclusion Bodies ; metabolism ; pathology ; Infant ; Toes

Actins ; metabolism ; Angiomyolipoma ; metabolism ; pathology ; surgery ; Epiglottis ; Factor VIII ; metabolism ; Humans ; Laryngeal Neoplasms ; metabolism ; pathology ; surgery ; Male ; Middle Aged

The present study clarified the molecular mechanism of curcumol against liver fibrosis based on its effects on the autopha-gy and apoptosis of hepatic stellate cells. The hepatic stellate cells were divided into a blank control group, a transforming growth factor-β1(TGF-β1)(10 ng·mL~(-1)) group, and low-(12.5 mg·L~(-1)), medium-(25 mg·L~(-1)), and high-dose(50 mg·L~(-1)) curcumol groups. The effect of curcumol on the viability of hepatic stellate cells induced by TGF-β1 was detected by the MTT assay kit. The apo-ptosis in each group was determined by flow cytometry. Real-time fluorescence-based quantitative PCR(RT-PCR) was employed for the detection of mRNA expression of α-smooth muscle actin(α-SMA), type Ⅰ collagen(collagen Ⅰ), and type Ⅲ collagen(collagen Ⅲ). Western blot was used to detect the protein expression of p62, microtubule-associated protein 1 light chain 3(LC3), beclin1, B cell lymphoma 2(Bcl-2), and Bcl-2-associated X protein(Bax). Transmission electron microscopy(TEM) was used to observe cell morphology and autophagosome formation in each group. The autophagic flux was observed after cell infection with adenovirus under double fluorescence labeling. The cell viability assay revealed that compared with the TGF-β1 group, the curcumol groups showed significantly decreased cell viability. The apoptosis assay showed that the apoptosis rates of the curcumol groups were significantly higher than that of the TGF-β1 group. RT-PCR indicated that the mRNA expression of α-SMA, collagenⅠ, and collagen Ⅲ in the curcumol groups was significantly lower than that of the TGF-β1 group. Western blot showed that the expression of p62, LC3, beclin1, Bcl-2, and Bax in the curcumol groups was significantly different from that in the TGF-β1 group. As demonstrated by TEM, compared with the TGF-β1 group, the curcumol groups showed significantly increased autophagosomes. The detection of autophagic flow by the adenovirus under double fluorescence labeling showed that autolysosomes in the curcumol groups were significantly increased compared with those in the TGF-β1 group. Curcumol can induce the autophagy and apoptosis of hepatic stellate cells, which may be one of its anti-liver fibrosis mechanisms.
Actins/metabolism* ; Apoptosis ; Autophagy ; Hepatic Stellate Cells ; Humans ; Liver/metabolism* ; Liver Cirrhosis/metabolism* ; Sesquiterpenes ; Transforming Growth Factor beta1/metabolism*

Mice ; Animals ; Actins/metabolism* ; Actin Depolymerizing Factors/metabolism* ; TRPM Cation Channels ; Actin Cytoskeleton/metabolism* ; Nervous System/metabolism*