Proliferating Cell Nuclear Antibody Research Articles

The role of tribbles homolog 2 in vascular smooth muscle cell proliferation.

Tribbles homolog 2 (TRIB2) functions as an adapter protein that regulates signal transductions involved in a variety of cellular functions, including tumorigenesis. However, the role of TRIB2 in the proliferation of vascular smooth muscle cells (VSMCs) and the underlying expression mechanisms remain unclear. The present study investigated the role of TRIB2 in VSMC proliferation and revealed that TRIB2 expression increases following vascular injury and platelet-derived growth factor (PDGF)-BB-stimulated VSMCs. We found that pretreatment with diphenyleneiodonium (a nicotinamide adenine dinucleotide phosphate oxidase inhibitor), U0126 (an inhibitor of mitogen-activated protein kinase kinase 1 [MEK1]), or siRNA targeting the gene encoding early growth response 1 (EGR-1) significantly inhibits PDGF-BB-induced TRIB2 expression in VSMCs. Furthermore, TRIB2 knockdown significantly inhibits PDGF-BB-induced proliferation of VSMCs but does not affect the phosphorylation of AKT. However, phosphorylation of ERK1 and expression of proliferating cell nuclear antibody are significantly suppressed in VSMCs by PDGF-BB stimulation. Thus, PDGF-BB-induced TRIB2 expression is mediated by ROS/ERK/EGR-1 pathways and plays a critical role in VSMC proliferation via modulation of ERK activity. We propose TRIB2 as a promising therapeutic target for the prevention of neointima formation and vascular disease.

Efficacy of combined axitinib with dacarbazine in a B16F1 melanoma xenograft model

In this study, we evaluated the efficacy and intestinal side effects of the selective inhibitor of vascular endothelial growth factor (VEGF) receptors, axitinib and/or dacarbazine (DTIC), in a B16F1 melanoma xenograft model. C57BL/6 mice were subcutaneously inoculated with B16F1 melanoma cells. The study was randomized into four groups receiving either 0.5% carboxyl methylcellulose, DTIC, axitinib or a combination of DTIC and axitinib. When the experimental period was complete, the tumor tissues from each mouse were excised, photographed and weighed. The tumor and intestinal tissues were harvested with 4% paraformaldehyde, and paraffin-embedded sections were prepared for hematoxylin and eosin staining, immunohistochemical staining (with antibody specific to proliferating cell nuclear antibody) and terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling assays. The expression of the VEGF and matrix metalloproteinase 9 genes was analyzed using real-time polymerase chain reaction. No significant benefit to treatment with a combination of axitinib and DTIC, as opposed to axitinib alone, was observed; however, the combined treatment did not enhance the level of enteritis compared with that observed in the axitinb group. In addition, axitinib, as a single agent, demonstrated an improved treatment efficacy compared with DTIC. Therefore, axitinib represents a potential novel, efficient and safe anticancer agent, suggesting a possible use for this schedule in treating melanomas that are less sensitive to DTIC.

Radial pressure waves mediate apoptosis and functional angiogenesis during wound repair in ApoE deficient mice

This study aims to quantify by intravital microscopy and histological wound scoring the effect of radial pressure wave treatment (RPWT) on murine incisional wound healing. The dorsal skinfold chamber in mice was used for intravital microscopy, whereby an incisional wound was created within the chamber. RPWT to the wound was carried out using a ballistic pressure wave source (EMS Swiss DolorClast). Animals received a dose of 500 pulses at an energy flux rate of 0.1mJ/mm2 and a frequency of 3Hz at day 1, 3, 5, 7, 9, and 11 post wounding. RPW treated and untreated ApoE depleted mice (ApoE−/−) were compared to normal healing wild type animals (WT). The microcirculation of the wound was analyzed quantitatively in vivo using epi-illumination intravital fluorescence microscopy. Tissue samples were examined ex vivo for wound scoring and immunohistochemistry. Upon RPWT total wound score in ApoE−/− mice was increased by 13% (not significant) on day 3, by 37% on day 7 (P<0.05), and by 39% on day 13 (P<0.05) when compared to untreated ApoE−/− mice. Improved wound healing was associated with an increase of functional angiogenetic density by 23% (not significant) on day 5, by 36% on day 7 (P<0.05), and by 41% on day 9 (P<0.05). Following RPWT, on day three we observed enhanced expression of capase-3 (2-fold), proliferating cell nuclear antibody (PCNA, 1,6-fold), and endothelial nitric oxide synthase (eNOS, 2.6-fold), all P<0.05. In conclusion repetitive RPWT accelerated wound healing in ApoE−/− mice by increasing functional neovascular density. In addition our findings strongly suggest that RPW may facilitate the linear progression of wound healing phases by fostering apoptosis.

Histological evidence for skin rejuvenation using a combination of pneumatic energy, broadband light, and growth factor therapy

Background and objective: A variety of laser or light-based devices have been developed for skin rejuvenation. This study evaluates the efficacy (at the microscopic level) of a combination of pneumatic energy, broadband light, and profusion tip-delivered epidermal growth factor (EGF). Methods: Healthy adult Japanese volunteers were recruited for this study. The posterior parts of the left and right arms were treated with a device that combines pneumatic energy and broadband light (Isolaz device). The left arms were also treated with EGF through a tip. Each subject received four treatments at 10-day intervals. Biopsy specimens obtained 3 weeks after the second treatment and 3 weeks after the fourth treatment were examined for histological study. Results: After two treatments, elastin fibers and fibroblasts in the dermal papillary layers of the left arms were increased compared to the right arms. A mean of 173.9 cells positive for proliferating cell nuclear antibody (PCNA) were observed on the left arm compared to 101.0 on the right arm. After the fourth treatment, angiogenesis and increased collagen fibers were observed in the dermal papillary layers of both arms. Conclusion: Four treatments with the addition of the profusion tip appear to hasten new collagen and elastin fiber formation, and the increase of PCNA positive cells so that dermal remodeling begins at an earlier stage than with the Isolaz alone.

Microvascular Response to Shock Wave Application in Striated Skin Muscle

This study aims to quantify by intravital microscopy the microhemodynamic response after extracorporeal shock wave application (ESWA) to the physiologic microcirculation of the mouse dorsal skinfold chamber. ESWA was carried out using an electrohydraulic shock wave source. Two different shock wave doses of 500 and 1000 pulses at an energy flux rate of 0.08 mJ/mm(2) and a frequency of 4 Hz were compared with sham-operated animals. Microcirculatory analyses were performed at baseline (BL) and during a 3 d observation period after ESWA. The expression of caspase-3 (casp-3), proliferating cell nuclear antibody (PCNA), von Willebrand factor (vWF), and endothelial nitric oxide synthase (eNOS) were analyzed semiquantitatively by immunohistochemistry. ESWA provoked a significant and persistent increase of functional capillary density (FCD) throughout the observation period, reaching a maximum (140% ± 5% of BL, P < 0.05 versus sham) after 1 d when animals were treated with 1000 pulses. ESWA induced a slight increase of leukocyte rolling (∼2- to ∼3.5-fold, P < 0.05) and leukocyte adherence (∼1.5- to ∼2-fold, P < 0.05) to the endothelial lining of postcapillary venules. One day following ESWA, we observed enhanced expression of casp-3 (∼3- to ∼4-fold), PCNA (∼9- to ∼14-fold), vWF (∼11- to ∼14-fold), and eNOS (∼3-fold), all P < 0.05. This study shows that ESWA provokes a favorable persistent increase of patent capillaries, however accompanied by a transient and slight inflammatory response but also by dose-dependant apoptotic cell death. Our data suggest that ESWA might represent a noninvasive biomechanical tool to treat critically perfused and endangered tissues, but certainly warrants further investigation.

Folic Acid Supplementation for 4 Weeks Affects Liver Morphology in Aged Rats

Several countries have approved universal folic acid (FA) fortification to prevent neural tube defects and/or high homocysteine levels; this has led to a chronic intake of FA. Traditionally, the vitamin is considered to be safe and nontoxic, except for the potential masking of vitamin B-12 deficiency. Recent reports from our laboratories showed several effects of high-dose folate supplementation in rats. In this work, we compared the effect of FA on the liver of weanling (3 wk) and aged (18 mo) male rats fed either a diet supplemented with 40 mg FA/kg diet or a control diet (1 mg FA/kg diet) for 4 wk. FA supplementation did not alter serum aspartate aminotransferase, alanine aminotransferase, urea, glucose oxidase, total bilirubin, or uric acid. Routine histological staining as well as immunohistochemistry with proliferating cell nuclear antibody for dividing cells, and cytokeratin-8 against bile ductal cells, showed that aged, supplemented rats had the same number of hepatocytes as both control and supplemented weanling rats, and tended to have more (17%, P = 0.07) hepatocytes than aged, control rats. Moreover, the bile duct cells of aged, control rats proliferated and transformed into cholestatic rosettes at a higher frequency than in aged, supplemented rats. The morphology of the liver in weanling rats was similar in both diet groups, and comparable to the supplemented, aged rats, thus indicating that a high intake of FA improves normal liver morphology in livers of aged rats.

Histological and Immunohistochemical Study of the Bronchial Stump with Flap Coverage in an Animal Model

Objective: The purpose of our study was to evaluate the healing process of the bronchial stump after pneumonectomy reinforced with different pedicled flaps in an animal model. The specimens were analyzed by means of histology and immunohistochemistry. Materials and Methods: We have considered 45 New Zealand White male rabbits that underwent a left pneumonectomy under general anesthesia. Nine animals had no bronchial coverage and represented the controls. The other 36 rabbits were divided into three groups of 12 and had bronchial coverage with either diaphragmatic, intercostal or pericardial flaps. The histological examinations were performed on the animals sacrificed 7, 14 and 30 days after surgery. Immunohistochemical analyses were done on the specimens on postoperative day 7 and 14. On postoperative day 7, the specimens were examined for expression of proliferating cell nuclear antibody (PCNA) expression. On postoperative day 14, neoangiogenesis was measured by CD31 expression. The measurements of antibody expression were done with a computer-assisted morphometric count and analyzed with the t test. Results: On postoperative day 14, standard histology showed more evident neoangiogenesis in the bronchial stump specimens covered with intercostal and diaphragmatic flaps compared to pericardial flaps and controls. The immunohistochemical evaluation of PCNA by morphometric computer-assisted analysis did not show any statistically significant differences among the groups. The CD31 morphometric count revealed a higher and statistically significant antibody expression in muscular flaps compared to pericardial flaps and controls. Conclusions: Our study showed that bronchial coverage with a pedicled muscular flaps promotes the production of new vessels and gives the possibilities to optimize the healing process of a bronchial stump after pneumonectomy.

Granulomatous 'foreign body reactions' contribute to exaggerated in-stent restenosis.

Results of previous studies with stents coated with 'biocompatible' polymers showed that severe inflammatory reaction and subsequent in-stent restenosis may occur. To evaluate the contribution of granulomatous reaction from uncoated stents to formation of in-stent neointimal hyperplasia. Uncoated stainless-steel stents were implanted into 21 porcine coronary arteries without oversizing and harvested after 2 months (n = 6) or 6 months (n = 7). We compared the stents with granulomatous reaction with those without foreign-body reaction. Granulomatous reactions occurred in five 21 stents and resulted in there being significantly greater in-stent neointimal hyperplasia than there was with stents without foreign-body reaction (angiographic diameter stenosis 45 +/- 36 versus 16 +/- 16%, area of neointimal 3.30 +/- 1.4 versus 1.22 +/- 0.4 mm2, thickness of neointima 0.46 +/- 0.29 versus 0.11 +/- 0.09 mm, stenosed area 56 +/- 24 versus 20 +/- 7%, P < 0.01 for each comparison). This increase in amount of neointima was accompanied by significantly greater proliferating cell nuclear antibody staining (15 +/- 5 versus 3 +/- 2%, P < 0.05) in the presence of a granuloma near the stent struts. A localized granulomatous reaction is associated with a significant increase in amount of stent neointima and proliferation of cells. Thus, permanent stent implants may provoke granulomatous vascular reactions that may affect late-healing responses and clinical outcomes.