The Effect of Garlic and Voluntary Exercise on Cardiac Angiogenesis in Diabetes: The Role of MiR-126 and MiR-210 / O Efeito do Alho e de Exercícios Físicos Voluntários na Angiogênese Cardíaca no Diabetes: O Papel do miRNA-126 e do miRNA-210

Abstract Background: Diabetes mellitus (DM) is one of the major risk factors for cardiovascular disease, leading to endothelial dysfunction and angiogenesis impairment . MiR-126 and miR-210 support angiogenic response in endothelial cells. Objective: The present study sought to explore the effect of garlic and voluntary exercise, alone or together, on miR-126 and miR-210 expressions and cardiac angiogenesis in rats with type 1 diabetes. Methods: Male Wistar rats were divided into five groups (n = 7): Control, Diabetes, Diabetes+Garlic, Diabetes+Exercise, and Diabetes+Garlic+Exercise. Diabetes was induced in the animals by streptozotocin (ip, 50 mg/kg). The rats were then fed raw fresh garlic homogenate (250 mg/kg) or were subjected to voluntary exercise, or to combined garlic and voluntary exercise for 6 weeks. MiR-126 and miR-210 expressions in the myocardium were determined by real time PCR, and the serum lipid profile was measured by enzymatic kits. Angiogenesis was evaluated by immunostaining for PECAM-1/ CD31 in the myocardium. Results: Diabetes reduced both cardiac miR-126 expression and angiogenesis (p < 0.05). On the other hand, there was a miR-210 expression increase in the myocardium of diabetic animals (p < 0.001). However, those effects reversed either with garlic or voluntary exercise (p < 0.01). Moreover, treating diabetic rats with garlic and voluntary exercise combined had an additional effect on the expressions of miR-126 and miR-210 (p < 0.001). Furthermore, both voluntary exercise and garlic significantly improved serum lipid profiles (p < 0.001). Conclusion: The induction of diabetes decreased angiogenesis in the myocardium, whereas our treatment using long-term voluntary exercise and garlic improved myocardial angiogenesis. These changes were possibly owing to the enhancement of myocardial miR-126 and miR-210 expressions.

Resumo Fundamento: O diabetes mellitus (DM) é um dos principais fatores de risco para doenças cardiovasculares, levando à disfunção endotelial e inibição da angiogênese. O miRNA-126 e o miRNA-210 promovem a resposta angiogênica em células endoteliais. Objetivo: O presente estudo buscou explorar o efeito do alho e de exercícios físicos voluntários, isoladamente ou em conjunto, nas expressões do miRNA-126 e do miR-210 e na angiogênese cardíaca em ratos com diabetes tipo 1. Métodos: Ratos Wistar machos foram divididos em cinco grupos (n = 7): Controle, Diabetes, Diabetes+Alho, Diabetes+Exercícios e Diabetes+Alho+Exercícios. Introduziu-se diabetes nos animais por estreptozotocina (ip, 50 mg/kg). Os ratos foram então alimentados com homogenato de alho fresco cru (250 mg/kg), ou foram submetidos a exercícios voluntários, ou a uma combinação de alho e exercícios voluntários, durante 6 semanas. As expressões do miRNA-126 e do miRNA-210 no miocárdio foram determinadas por PCR em tempo real, e o perfil lipídico sérico foi medido por kits enzimáticos. A angiogênese foi avaliada por imunocoloração por PECAM-1/CD31 no miocárdio Resultados: O diabetes reduziu a expressão do miRNA-126 cardíaco e da angiogênese (p < 0,05). Por outro lado, houve um aumento da expressão do miRNA-210 no miocárdio dos animais diabéticos (p < 0,001). No entanto, tais efeitos foram revertidos com alho ou exercícios voluntários (p < 0,01). Além disso, o tratamento de ratos diabéticos conjuntamente com alho e exercícios voluntários teve um efeito adicional sobre as expressões do miRNA-126 e do miRNA-210 (p < 0,001). Além disso, tanto os exercícios voluntários quanto o alho melhoraram significativamente os perfis lipídicos séricos (p < 0,001). Conclusões: A indução de diabetes diminuiu a angiogênese no miocárdio, enquanto nosso tratamento com exercícios voluntários de longa duração e alho melhorou a angiogênese miocárdica. Estas alterações devem-se, possivelmente, ao aumento das expressões do miRNA-126 e do miRNA no miocárdio.

The Effect of Garlic and Voluntary Exercise on Cardiac Angiogenesis in Diabetes: The Role of MiR-126 and MiR-210.

BACKGROUND: Diabetes mellitus (DM) is one of the major risk factors for cardiovascular disease, leading to endothelial dysfunction and angiogenesis impairment . MiR-126 and miR-210 support angiogenic response in endothelial cells. OBJECTIVE: The present study sought to explore the effect of garlic and voluntary exercise, alone or together, on miR-126 and miR-210 expressions and cardiac angiogenesis in rats with type 1 diabetes. METHODS: Male Wistar rats were divided into five groups (n = 7): Control, Diabetes, Diabetes+Garlic, Diabetes+Exercise, and Diabetes+Garlic+Exercise. Diabetes was induced in the animals by streptozotocin (ip, 50 mg/kg). The rats were then fed raw fresh garlic homogenate (250 mg/kg) or were subjected to voluntary exercise, or to combined garlic and voluntary exercise for 6 weeks. MiR-126 and miR-210 expressions in the myocardium were determined by real time PCR, and the serum lipid profile was measured by enzymatic kits. Angiogenesis was evaluated by immunostaining for PECAM-1/ CD31 in the myocardium. RESULTS: Diabetes reduced both cardiac miR-126 expression and angiogenesis (p < 0.05). On the other hand, there was a miR-210 expression increase in the myocardium of diabetic animals (p < 0.001). However, those effects reversed either with garlic or voluntary exercise (p < 0.01). Moreover, treating diabetic rats with garlic and voluntary exercise combined had an additional effect on the expressions of miR-126 and miR-210 (p < 0.001). Furthermore, both voluntary exercise and garlic significantly improved serum lipid profiles (p < 0.001). CONCLUSION: The induction of diabetes decreased angiogenesis in the myocardium, whereas our treatment using long-term voluntary exercise and garlic improved myocardial angiogenesis. These changes were possibly owing to the enhancement of myocardial miR-126 and miR-210 expressions.

Garlicin Post-Conditioning Suppresses Adhesion Molecules in a Porcine Model of Myocardial Ischemia-Reperfusion Injury.

OBJECTIVES: To evaluate whether garlicin post-conditioning can attenuate myocardial ischemiareperfusion injury in a catheter-based porcine model of acute myocardial infarction (AMI) by affecting adhesion molecules integrin ß1/CD29 and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31). METHODS: Twenty-two swine were devided into 3 groups: 6 in a sham-operation group, and 8 each in the model and garlicin groups. AMI porcine model was established in the model and garlicin groups. The distal parts of the left anterior descending coronary artery in the animals of the model and garlicin groups were occluded by dilated balloon for 2 h, followed by reperfusion for 3 h. Garlicin (1.88 mg/kg) was injected over a period of 1 h, beginning just before reperfusion, in the garlicin group. Real-time polymerase chain reaction, immunohistochemistry and Western blot were carried out to detect mRNA and protein expressions of CD29 and CD31 3 h after reperfusion. RESULTS: Hematoxylin-eosin staining showed a better myocardial structure in the garlicin group after reperfusion. Compared to the model group, garlicin inhibited both the mRNA and protein expression of CD29 and CD31 in reperfusion area and no-reflflow area (P<0.05 respectively). CONCLUSIONS: Garlicin post-conditioning induced cardio-protection against myocardial ischemia-reperfusion injury in this catheter-based porcine model of AMI. The cardio-protective effect of garlicin is possibly owing to suppression of production of CD29 and CD31, by inhibition of the mRNA expression of CD29 and CD31.

Green tea prevents vascular disturbs and attenuates periodontal breakdown in long-term hyperglycaemia in T1D rats.

AIM: The effects of green tea on the modulation of vascularization during the progression of spontaneous periodontitis in long-term hyperglycaemia in streptozotocin-induced type 1 diabetic (T1D) rats were evaluated. MATERIALS AND METHODS: Wistar rats normoglycaemic (NG) and T1D were divided into two control groups, which received water (NG-W and T1D-W) and two experimental groups that received green tea (NG-GT and T1D-GT). Periodontal structures were evaluated by microtomographic and histological analyses. Number of immunostained cells for VEGF (NcVEGF+/mm2 ) and CD31 (NcCD31+/mm2 ), as well microvessel density (MVD) in the periodontal ligament (PDL) were evaluated. RESULTS: Long-term hyperglycaemia in T1D-W rats induced vascular alterations in PDL with a reduction of 36% in MVD, a decrease of 33% in NcCD31+/mm2 and an increase of 53% in NcVEGF+/mm2 . Concomitantly, a severe degree of periodontitis with higher reduction in bone volume and periodontal bone level was observed. In T1D-GT, green tea maintained the MVD, NcCD31+/mm2 and NcVEGF+/mm2 in the PDL similar to normoglycaemic groups. Clinically, in T1D-GT rats, green tea reduced dental plaque accumulation and the degree of periodontitis when compared to T1D-W. CONCLUSION: Daily green tea consumption has a therapeutic effect on the diabetic vascular disorder in PDL and the progression of periodontitis in long-term hyperglycaemia in T1D rats.

Zinc effect on human lymphatic malformation cells in vitro.

OBJECTIVES: Lymphatic malformations (LM) are clinically characterized by episodes of inflammatory episodes. Often, an upper respiratory illness or trauma will lead to painful swelling in the distribution of the LM. Zinc is an element involved in numerous aspects of cellular metabolism and is a common dietary supplement and cold remedy. We surmise that zinc may act as a therapeutic anti-inflammatory agent for lymphatic malformations and their cellular components. We investigate the apparent cytotoxic effect of zinc ion on lymphatic malformation cells in vitro. METHODS: Fresh surgical lymphatic malformation specimens from 10 patients were collected and processed in a laboratory. Tissues were processed and lymphatic malformation cells were isolated and grown. Immunohistochemistry and cell morphology were used to confirm LM cells. HUVEC cells were used as controls. Zinc chloride solution was added to the cells and its effect observed. RESULTS: LM cells were isolated from five of the 10 specimens. Of these, the cells of only one specimen were able to be amplified to confluence. Five specimens were contaminated. Immunohistochemical staining (CD31, D2-40, and LYVE-1) and cell morphology of our specimens were consistent with lymphatic malformation while HUVEC control cells were negative. Zinc has a cytotoxic effect on BEL isolates in vitro with no obvious effect on cell morphology or growth rate of the control HUVEC cells. When compared with the published toxic zinc concentration for most cell types in the literature (100µM total zinc in vitro), our result indicates that LM cells may have a lower tolerance to zinc (10µM total zinc in vitro). CONCLUSION: Zinc has an apparent morphological effect on lymphatic malformation cells in vitro. Compared with other cell types, LM cells have a lower tolerance to zinc. While this result looks very promising for future therapeutic use of zinc in acute lymphangitis, further studies are necessary, such as finding the IC50 of zinc for lymphatic malformation in vitro and also in vivo.

Synergic antitumor effect of SKLB1002 and local hyperthermia in 4T1 and CT26.

A de novo VEGFR2-inhibited compound SKLB1002 which is independently developed in our laboratory has been described for antiangiogenesis and displays a potent antitumor activity in vivo and in vitro. In the present investigation, we aim to prove that combination therapy of SKLB1002 with hyperthermia plays a synergy as an antitumor agent in solid tumor. In this study, we analyzed their synergetic inhibitory action on human umbilical vein endothelial cells (HUVEC), murine mammary cancer 4T1, murine colon carcinoma CT26 in vitro. Multiply-table tournament was performed to detect cell proliferation in vitro. 4T1 implantation and CT26 implantation in BALB/c mice were used to examine the activity of combination therapy of SKLB1002 with hyperthermia in vivo. Vascular density was determined by CD31 immunohistochemistry. TUNEL was used to measure apoptosis in tumor tissue. Metastasis assay was investigated via measurement of pulmonary metastasis nodules under the microscope. Potential toxicity of combination therapy was observed by histologic analysis of main organs stained with H&E. In vitro, the combination therapy significantly inhibited cell proliferation of HUVEC, 4T1 and CT26. In vivo, 4T1 and CT26 model experiments showed that combination therapy remarkably inhibited tumor growth and prolonged life span. When compared with controls, combination therapy reached 61 % inhibition index of tumor growth against CT26 and 51 % against 4T1. Moreover, it reduced angiogenesis and increased tumor apoptosis and necrosis. It was further found that combination therapy could efficiently prevent tumor from metastasizing to lung. Importantly, it had no toxicity to main organs including heart, liver, spleen, lung and kidney. Combination treatment has been proved to be a novel and strong strategy in clinical antitumor therapy. Our findings suggest that the combination therapy of SKLB1002 with hyperthermia has a synergistic antiangiogenesis, anticancer and promotion of apoptosis efficacy compared with controls. These findings could pave a new way in clinical tumor therapy.

Techniques to harvest diseased human peripheral arteries and measure endothelial function in an ex vivo model.

OBJECTIVE: Endothelial dysfunction has been studied in animal models. However, direct evidence of endothelial function from human vessels is limited. Our objectives were to optimize methods in harvesting human arteries from amputation specimens, determine endothelial function, and measure responsiveness to l-arginine, a nitric oxide precursor. METHODS: Fresh amputation specimens were transferred expeditiously from the operating room to the bench laboratory for dissection and arterial harvest in an Investigational Review Board-approved protocol. Popliteal and tibial vessels were examined in pilot experiments leading to the use of the anterior tibial artery in consecutive experiments. Human lower extremity anterior tibial artery segments were harvested from 14 amputation specimens. Specimens were rapidly collected and divided for endothelial-dependent relaxation (EDR) studies in a tissue bath apparatus, immunohistochemistry, and intravascular ultrasound-derived virtual histology. A total of 47 ring segments were studied. The data were compared with two-way analysis of variance. RESULTS: Human lower extremity arteries exhibited low responsiveness to acetylcholine (EDR, 24.9%; acetylcholine, 10(-4)). L-arginine supplementation enhanced EDR by 38.5% (P < .0001). N-nitro-L-arginine methyl ester abrogated EDR (P < .0001) in vessels exposed to L-arginine. Arterial responsiveness was intact in all vessels (endothelial independent relaxation to sodium nitroprusside, 113.2% ± 28.1%). Histology and immunohistochemistry confirmed intact endothelium by morphometric analysis, cluster of differentiation 31, endothelial nitric oxide synthase, and arginase II staining. Intravascular ultrasound-derived virtual histology indicated atheroma burden was 11.9 ± 4.7 mm(3)/cm, and plaque stratification indicated fibrous morphology was predominant (59.9%; necrotic core, 16.9%; calcium, 11.2%). Variations in plaque morphology did not correlate with endothelial function or responsiveness to L-arginine. CONCLUSIONS: Human lower extremity arteries demonstrate low baseline endothelial function in patients requiring amputation. Endothelial dysfunction is improved by L-arginine supplementation in an ex vivo model. These results support strategies to increase local levels of nitric oxide in human vessels.

Hyperbaric oxygen stimulates vascularization and bone formation in rat calvarial defects.

Hyperbaric oxygen (HBO) therapy is used to treat or prevent tissue necrosis in patients undergoing irradiation. Many such patients require reconstructive surgery, but little is known of the effects of HBO on bone vascularization and regeneration. In this study, copolymer poly(l-lactide-co-1,5-dioxepan-2-one) (poly(LLA-co-DXO)) scaffolds were implanted into critical-sized calvarial defects in Wistar rats. The animals were randomly allotted to hyperbaric or normobaric oxygen groups. The treatment group received five sessions weekly for 90 min at increased atmospheric pressure, for up to 4 weeks. Samples were retrieved at weeks 2 and 8, i.e. after a total of 10 and 20 sessions, respectively. The samples were analyzed by real-time reverse transcriptase polymerase chain reaction (RT-PCR) and histology at week 2, and radiographically and histologically at week 8. At week 2, defects treated with HBO exhibited greater numbers of cells positive for the endothelial marker CD31, up-regulated gene expression of osteogenic markers, and down-regulated expression of pro-inflammatory cytokines. At week 8, radiographic examination revealed that calvarial defects subjected to HBO exhibited a higher percentage of radiopacities than normobaric controls, and histological examination disclosed enhanced bone healing. These results confirmed that HBO treatment was effective in stimulating vascularization and bone formation in rat calvarial defects.

Biomarkers of phenethyl isothiocyanate-mediated mammary cancer chemoprevention in a clinically relevant mouse model.

BACKGROUND: Phenethyl isothiocyanate (PEITC) is a natural plant compound with chemopreventative potential against some cancers and the ability to induce apoptosis in breast cancer cells. METHODS: Female mouse mammary tumor virus-neu mice were fed a control AIN-76A diet (n = 35) or the same diet supplemented with 3 µmol PEITC/g diet (n = 33) for 29 weeks, at which time they were killed. Breast tissue sections were stained with hematoxylin and eosin for histopathological assessments, and incidence and size of macroscopic mammary tumors were assessed. Cell proliferation (Ki-67 staining), apoptosis (terminal deoxynucleotidyl transferase-mediated dUTP nick-labeling), and neoangiogenesis (CD31 staining) were determined in tumor sections. Plasma levels of transthyretin were measured in treated and control mice. Expression of proteins in mammary tumor sections was determined by immunohistochemistry. Proteomic profiling was performed by two-dimensional gel electrophoresis followed by mass spectrometry. All statistical tests were two-sided. RESULTS: Administration of PEITC for 29 weeks was associated with 53.13% decreased incidence of macroscopic mammary tumors (mean tumor incidence, PEITC-supplemented diet vs control diet, 18.75% vs 40.00%, difference = -21.25%, 95% confidence interval [CI] = -43.19% to 0.69%, P = .07) and with a 56.25% reduction in microscopic mammary carcinoma lesions greater than 2 mm(2) (mean incidence, PEITC-supplemented diet vs control diet, 18.75% vs 42.86%, difference = -24.11%, 95% CI = -46.35% to -1.86%, P = .04). PEITC-mediated mammary cancer growth inhibition was not because of suppression of human epidermal growth factor receptor-2 expression but was associated with reduced cellular proliferation and neoangiogenesis, increased apoptosis, and altered expression of several proteins, including decreased ATP synthase in the tumor and increased plasma levels of transthyretin. CONCLUSIONS: PEITC inhibits the growth of mammary cancers in a mouse model with similarities to human breast cancer progression. ATP synthase and transthyretin appear to be novel biomarkers associated with PEITC exposure.

Sairei-to ameliorates rat peritoneal fibrosis partly through suppression of oxidative stress.

BACKGROUND: Sairei-to is a herbal prescription originating from traditional Chinese medicine. We conducted an experimental study on rat peritoneal fibrosis to clarify the suppressive mechanisms of sairei-to. METHODS: Wistar rats were intraperitoneally injected with chlorhexidine gluconate (CG) every day. Peritoneal specimens were collected after 28 days of CG injection and oral administration of sairei-to. Macrophage infiltration, extracellular matrix accumulation, and angiogenesis were evaluated by immunostaining for ED-1, fibronectin, and CD-31, respectively. To observe oxidative stress in the tissue, 4-hydroxy-2-noneal (HNE) accumulation and plasma levels of superoxide dismutase (SOD) activity were detected. As a candidate of antioxidative components in sairei-to, plasma levels of baicalin were determined by high-performance liquid chromatography. RESULTS: Compared with the disease control group, serum total protein levels were significantly recovered in the sairei-to treatment group. Thickness of the submesothelial compact zone, trichrome-stained area, ED-1-positive cells, fibronectin-staining area, and HNE accumulation were suppressed in the treatment group. Concurrently, decreased plasma levels of SOD activity were recovered by sairei-to treatment. Increased CD-31-positive vessel number and area were also suppressed in the sairei-to group. Baicalin was detected in the plasma samples of the sairei-to group at 0.29 ± 0.11 µg/ml (mean±SEM). CONCLUSION: These results suggest that sairei-to ameliorates peritoneal fibrosis, partly through suppressing oxidative stress and macrophage infiltration.

Nd: YAG laser (1,064 nm) fails to improve localized plaque type psoriasis: a clinical and immunohistochemical pilot study.

Chronic and localized plaque-type-psoriasis is often therapy resistant as a result of which dermatologists often have trouble finding a suitable treatment option. Traditional therapies for psoriasis merely focus on the inhibition of epidermal proliferation, inflammation, or both. The earliest changes, however, in a novel psoriatic lesion concern abnormal microvasculature. The position of lasers in the treatment of psoriatic lesions is debatable, as different views exist with respect to efficacy and tolerability. The current investigation evaluates the clinical and immunohistochemical effect of the Nd:YAG (1,064 nm) laser in chronic localized psoriasis, as this laser can penetrate up to the deeper abnormal psoriatic vasculature. The effects are compared to treatment with the well-established calcipotriol/betamethasone dipropionate ointment. The use of the Nd:YAG laser with treatment-intervals of four weeks was found not to be of additional value in the array of treatment modalities for chronic localized plaque-psoriasis. Targeting the more superficially located microvasculature in psoriasis seems of stronger significance for achieving a clinical effect than the deeper vasculature targeted by the Nd:YAG laser. Therefore, the present data are of importance in preserving dermatologists from treating psoriatic lesions with a Nd:YAG laser. However, further studies incorporating changes in methodology, in particular shortened time-intervals between treatments, are needed in order to refute or confirm this position.

Suprasellar hemangioblastoma.

A 59-year-old woman presented with disturbance of consciousness and decreased visual acuity caused by a suprasellar mass identified on MRI. A bifrontal interhemispheric approach allowed removal of the top and lateral sides of the tumor from the wall of the third ventricle. The hypothalamus appeared to be the origin of the mass, which proved to be hemangioblastoma, a rare tumor in this location.

[The effects of lipiodol-hydroxyapatite nanoparticle on apoptosis, proliferation, and angiogenesis in hepatic tumor: experiment with rabbits].

OBJECTIVE: To investigate the effects of lipiodol-hydroxyapatite nanoparticle (lipi-nHAP) on the growth, necrosis, apoptosis, proliferation, and angiogenesis of hepatic tumor. METHODS: Ultrasound-emulsification was used to make lipi-nHAP Eighty New Zealand white rabbits underwent implantation of carcinoma cells of the line VX2 into the left lobe of liver. Two weeks later the rabbits underwent catheterization into the gastroduodenal artery so that, and then the rabbits were randomly divided into four equal groups to receive infusion via the hepatic artery of different drugs: physiological saline (Group A), lipiodol (Group B), adriamycin + lipiodol (Group C), and lipi-nHAP (Group D). Seven and 14 days after the treatment the size of tumor was observed by spiral CT scan, and the volume and growth rate of tumor were calculated. Two weeks after the treatment 8 rabbits from each group were killed and their liver tumors were taken out and the survival rates of remaining rabbits were observed. The necrosis rate of the liver tumor was assessed by measuring the area of the tumor and the necrosis. The apoptotic rate was examined by TUNEL method. Mcrovessel density (MVD) was examined by immunohistochemistry anti-CD31 antibody. Anti-proliferating cell nuclear antigen (PCNA) monoclonal antibody was used to detect the expression of PCNA so as to calculate the proliferation index of the cells. RESULTS: The tumor volume and growth rate of Group D 7 and 14 days after treatment were both significantly lower than those of other groups (all P < 0.05) and the necrosis rate and apoptotic index of Group D were both significantly higher than those of other groups (all P < 0.05). The values of MVD were higher in Groups C and D compared with those of Group A. Compared with those in other groups, the values of MVD and expression level of PCNA were significantly lower in group D (all P < 0.05). The survival time of Group D was longer than those of other groups (all P < 0.05). CONCLUSION: lipi-nHAP can suppress the growth of tumor, increase the tumor's necrosis rate and apoptotic index, inhibit the development of neovascularization, decrease the expression level of PCNA of residual tumor, and prolong the surviving time of the animals with hepatic tumor. It may become an effective embolization material to treat liver cancer.

Retinoids increase lung elastin expression but fail to alter morphology or angiogenesis genes in premature ventilated baboons.

Retinoids regulate elastin synthesis by alveolar myofibroblasts and affect angiogenesis pathways, both of which are processes critical for alveolar development. Retinoids accelerate alveolarization in rodents and are now used therapeutically in premature infants at risk of bronchopulmonary dysplasia (BPD). This study examined the effects of retinoid supplementation on alveolar elastin expression and deposition and angiogenesis-related signaling in a primate model of BPD. Premature baboons delivered at 125 d of gestation after maternal steroid treatment were given surfactant and ventilated with minimal supplemental oxygen for 14 d with (n = 5) and without (n = 5) supplemental vitamin A (5000 U/kg/d) and compared with 140-d unventilated controls. Ventilatory efficiency index (VEI) and oxygenation index (OI) were not statistically different between ventilated treatment groups. Expression of vascular endothelial growth factor A (VEGF-A), fms-related tyrosine kinase 1 (Flt-1), and tyrosine kinase with immunoglobulin-like and EGF-like domains 1 (TIE-1) was repressed by premature delivery and mechanical ventilation and was not altered by retinoid supplementation. Retinoid supplementation did not enhance alveolar angiogenesis. Elastin expression was repressed by premature delivery and extended ventilation, and retinoid supplementation increased elastin expression specifically in alveolar myofibroblasts within alveolar walls. These results suggest that the small decrease in mortality among premature infants receiving retinoid supplementation may not be mediated through enhanced alveolar development.

The HUVEC/Matrigel assay: an in vivo assay of human angiogenesis suitable for drug validation.

The future ability to manipulate the growth of new blood vessels (angiogenesis) holds great promise for treating ischemic disease and cancer. Several models of human in vivo angiogenesis have been described, but they seem to depend on transgenic support and have not been validated in a therapeutic context. Here, we describe an in vivo assay that mimics human angiogenesis in which native human umbilical vein-derived endothelial cells are suspended in a liquid laminin/collagen gel (Matrigel), injected into immunodeficient mice, and develop into mature, functional vessels that vascularize the Matrigel plug in the course of 30 d. Moreover, we demonstrate how to target this process therapeutically by sustained delivery of the angiogenesis inhibitor endostatin from subcutaneously implanted microosmotic pumps.

Roles of nitric oxide synthase inhibition and vascular endothelial growth factor receptor-2 inhibition on vascular morphology and function in an in vivo model of pancreatic cancer.

PURPOSE: Both nitric oxide (NO) and vascular endothelial growth factor (VEGF) mediate tumor vascular function. Because these molecules regulate one another's expression, we hypothesized that NO synthase (NOS) inhibition produces effects comparable to those of anti-VEGF therapy on human pancreatic cancer xenografts. EXPERIMENTAL DESIGN: L3.6pl human pancreatic cancer cells were s.c. implanted in nude mice. On day 6, mice were randomized to receive (a) PBS (control), (b) DC101 [VEGF receptor 2 (VEGFR-2) antibody] by i.p. injection, (c) N-nitro-l-arginine (NNLA; NOS inhibitor) in the drinking water, or (d) both DC101 and NNLA. Mice were killed on day 20. RESULTS: DC101 and NNLA as single agents inhibited tumor growth by approximately 50% to 60% (P < 0.008 for both). Furthermore, combined therapy inhibited mean tumor growth by 89% (P < 0.008). Combined inhibition of VEGFR-2 and NOS also decreased mean vessel counts by 65% (P < 0.03) and vessel area by 80% versus controls (P < 0.001). In contrast to DC101 where vessel diameter was similar to control, NNLA decreased mean vessel diameter by 42% (P < 0.001). NNLA also led to a 54% (P < 0.03) decrease in tumor uptake of the perfusion marker Hoechst 33342 versus controls whereas DC101 decreased Hoechst 33342 staining by 43% (P < 0.03). The combination of inhibitors decreased perfusion by 73% (P < 0.03). CONCLUSIONS: Although VEGFR-2 can mediate NOS activity, the combination of VEGFR-2 and NOS inhibition significantly increased the antivascular effect over single agent therapy. The addition of NOS inhibition led to an even further alteration of tumor vessel morphology and vascular perfusion compared with VEGFR-2 blockade, suggesting that NO and VEGFR-2 have distinct but complementary effects on the tumor vasculature.

Carcinosarcoma of the prostate: two cases with distinctive morphologic and immunohistochemical findings.

Carcinosarcomas (CS) of the prostate are very uncommon neoplasms defined by the admixture of malignant epithelial and mesenchymal components. We describe here two new examples of CS in two patients aged 66 and 77 years, the first without previous history of prostate adenocarcinoma and the second with a 5-year history of acinar type prostate adenocarcinoma. The diagnosis of CS was made on the cystoprostatectomy specimen in the first case and transurethral resection in the second case. Both biphasic tumours exhibited papillary areas of ductal differentiation and conventional adenocarcinoma in the epithelial component, as well as malignant fibrous histiocytoma and angiosarcomatous areas in the first case and solid, poorly differentiated epithelial areas with neuroendocrine features in the second case. Immunohistochemistry revealed over-expression of c-erb B2 in the papillary epithelial component of both cases, whereas the solid undifferentiated epithelial areas in the second patient expressed c-kit, CD10 and synaptophysin, thus conforming a very undifferentiated cell population. The angiosarcomatous component of the first case expressed CD31 and CD10. The clinical course of the cases was divergent; the first patient is free of disease after radical surgery and adjuvant therapy and the other died 5 months after the diagnosis of CS, having already developed liver metastases.

Short-term effects of TNP-470 in combination with cisplatin in the rat model of bladder cancer.

PURPOSE: To investigate the short-term effects of TNP-470 in combination with cisplatin in a rat model of bladder cancer. MATERIALS AND METHODS: Following treatment of TNP-470 with or without cisplatin for 7 days, the states of angiogenesis, apoptosis and cell proliferation were evaluated in rat bladder cancer induced by N-butyl-N-(4-hydroxybutyl) nitrosamine. RESULTS: In comparison with untreated tumors, we noted a significantly decreased microvessel density (MVD) in the rat bladder cancer treated by TNP-470, and a significantly increased apoptotic index (AI) when treated by cisplatin. In TNP-470 plus cisplatin-treated tumors, both significantly decreased MVD and increased AI were observed in non-invasive and invasive rat bladder cancers in addition to a significantly decreased proliferation index (PI) in invasive cancer. CONCLUSION: The combination therapy of TNP-470 with cisplatin may act through both the inhibition of angiogenesis and induction of apoptosis, and invasive tumor cells may be much more sensitive to this combined therapy in rat bladder cancer.

Anti-tumor activities of the angiogenesis inhibitors interferon-inducible protein-10 and the calreticulin fragment vasostatin.

Tumor growth depends upon an adequate supply of oxygen and nutrients achieved through angiogenesis and maintenance of an intact tumor vasculature. Therapy with individual agents that target new vessel formation or existing vessels has suppressed experimental tumor growth, but rarely resulted in the eradication of tumors. We therefore tested the combined anti-tumor activity of vasostatin and interferon-inducible protein-10 (IP-10), agents that differently target the tumor vasculature. Vasostatin, a selective and direct inhibitor of endothelial cell proliferation, significantly reduced Burkitt tumor growth and tumor vessel density. IP-10, an "angiotoxic" chemokine, caused vascular damage and focal necrosis in Burkitt tumors. When combined, vasostatin plus IP-10 reduced tumor growth more effectively than each agent alone, but complete tumor regression was not observed. Microscopically, these tumors displayed focal necrosis and reduction in vessel density. Combination therapy with the inhibitors of angiogenesis vasostatin and IP-10 is effective in reducing the rate of tumor growth but fails to induce tumor regression, suggesting that curative treatment may require supplemental drugs targeting directly the tumor cells.