Stem cell therapy for arterial restenosis: potential parameters contributing to the success of bone marrow-derived mesenchymal stromal cells.

PURPOSE: Restenosis is a complex and heterogeneous pathophysiological phenomenon occurring in patients submitted to revascularization procedures. Previous studies proved the antirestenotic properties of injected allogenic mesenchymal stromal cells (MSCs) in an experimental model of rat carotid (re)stenosis induced through arteriotomy. In this study we describe some of the effects subsequent to MSC treatment of rats submitted to carotid arteriotomy and possibly responsible for their antirestenotic effect. METHODS: Rat MSCs were isolated from bone marrow, expanded in vitro and characterized. Subsequently, we evaluated the effects of MSC administration via tail vein at 3 and 7 days after carotid arteriotomy both in rat serum and in injured carotids, focusing on DNA oxidative damage (8-oxo-dG detection), cell proliferation index (BrdU incorporation assay), apoptotic index (TUNEL assay), the expression of inflammation- and proliferation-related genes (RT-PCR), the release of growth factors and of inflammation-related cytokines (antibody arrays and ELISA). RESULTS: MSC administration induced a greater cell proliferation in carotids after arteriotomy, together with an increased level of VEGF in the serum and with the higher expression of VEGF mRNA in injured carotids. Serum analysis also revealed a decreased level of the pro-inflammatory cytokines CXCL1, CXCL5, L-Selectin, ICAM-1 and LIX, and of TIMP1 and SDF-1alpha in MSC-treated rats. The MSC immunomodulatory activity was confirmed by the decreased expression of TLR2 and TLR4 in injured carotids. CONCLUSIONS: MSCs play an immunomodulatory paracrine role when injected in rats submitted to carotid arteriotomy, accompanied by the release of VEGF, possibly contributing to the accelerated repair of the injured vascular wall.

Cardioprotective effect of a moderate and prolonged exercise training involves sirtuin pathway.

AIM: To investigate the cardioprotective effects of prolonged and moderate exercise training on cellular and molecular events early after myocardial infarction. MATERIALS AND METHODS: Male Wistar rats were divided in sedentary or exercised group; both groups underwent to a myocardial infarction. All the molecular and immunohistochemical analyses on hearts of sedentary and exercised rats were performed 48 h after surgical procedure. SIRT1 and SIRT3 expression were measured and two of the pathways activated by sirtuins, p53-induced apoptosis and Forkhead boxO (FOXO)3a-induced oxidative stress, were investigated. All the experiments were performed also in presence of the SIRT inhibitor, EX527. KEY FINDINGS: Fourty-eight hours post myocardial infarction, exercise training induced the activation of SIRT1 and SIRT3 pathway reducing cardiomyocytes apoptosis and oxidative damage. Molecular data were confirmed by immunohistochemical evaluations. These effects are more evident in border infarcted zone than in the remote myocardium. SIGNIFICANCE: Exercise training is a non-pharmacological prevention strategy in cardiovascular diseases and the sirtuins family seems to be as novel and attractive target in cardioprotection.

Addition of the Aldose Reductase Inhibitor Benzofuroxane Derivative BF-5m to Prolonged and Moderate Exercise Training Enhanced Protection of the Rat Heart From Type-1 Diabetes.

Moderate exercise training may not be sufficient to exert beneficial effects on the cardiovascular system because of the long-term multifactorial etiology of diabetic complications. The addition of a proper pharmacological tool to the physical exercise should improve the outcomes of the diabetic damage. Here it is shown that 8 weeks exercise training of type 1 diabetic Sprague-Dawley (SD) rats resulted in a significantly increased heart rate, a 14% increase in the left ventricular ejection fraction (LVEF) increased plasma insulin levels and a 13% decrease in plasma glucose with respect to sedentary animals. The training also resulted in a 22% reduction in cardiac QT interval from a diabetic sedentary value of 185 ± 19 ms. Treatment of trained rats with the new antioxidant and NO-releasing aldose reductase 2 inhibitor 5(6)-(benzo[d]thiazol-2-ylmethoxy) benzofuroxane BF-5m, 20 mg/kg/day, added a further and significant (P < 0.01 vs. sedentary) increase of the LVEF up to 38% at 8 week time point. The long QT interval recorded in trained rats was reduced to further 12% by addition to the training of pharmacological treatment with 20 mg/kg/day BF-5m. At this time, the association of the two treatments improved the expression into the cardiac tissue of sarcoplasmic reticulum Ca2+ ATPase 2 (SERCA2) and manganese superoxide dismutase (MnSOD), and reduced the fibrosis.

Segmentectomy: is minimally invasive surgery going to change a liver dogma?

Nowadays, the respective approach to hepatic resections (for malignant or benign liver lesions) is oriented toward minimal parenchymal resection. This surgical behavior is sustained by several observations that surgical margin width is not correlated with recurrence of malignancies. Parenchymal-sparing resection reduces morbidity without changing long-term results and allows the possibility of re-do liver resection in case of recurrence. Minimally invasive liver surgery (MILS) is performed worldwide and is considered a standard of care for many surgical procedures. MILS is associated with less blood loss, less analgesic requirements, and shorter length of hospital with a better quality of life. One of the more frequent criticisms to MILS is that it represents a more challenging approach for anatomical segmentectomies and that in most cases a non-anatomical resection could be performed with thinner resection margins compared with open surgery. But even in the presence of reduced surgical margins, oncological results in the short- and long-term follow-up seem to be the same such as open surgery. The purpose of this review is to try to understand whether chasing at any cost laparoscopic anatomical segmentectomies is still necessary whereas non-anatomical resections, with a parenchymal-sparing behavior, are feasible and overall recommended also in a laparoscopic approach. The message coming from this review is that MILS is opening more and more new frontiers that are still need to be supported by further experience.

Our experience of liver Epithelioid Hemangioendothelioma: from a misdiagnosis to liver transplantation with long term follow-up.

Malignant Hepatic Epithelioid hemangioendothelioma (HEHE) is an uncommon vascular tumor of intermediate malignant potential. HEHE is a rare tumor and it is difficult to diagnose for surgeons, hepatologists, radiologists and pathologists. So, misdiagnosis with a delay of the treatment is not uncommon. We describe a case of a young woman with a diagnosis of HEHE made 6 years after the first evidence of liver mass with a very long term follow-up after surgical treatment. She had two diagnoses of Hepatocellurar carcinoma (HCC) and a diagnosis of Cholangiocarcinoma after three different fine needle biopsies. After clinical observation, a new laparoscopic core biopsy was performed. In a first time approach, considering clinical and radiological patterns, a diagnosis of Budd-Chiari Syndrome was finally made. For that the patient underwent an orthotopicliver transplantation (OLTx). The surgical sample histological analysis allowed a definitive diagnosis of HEHE. At last, at follow up 7 years after three OLTx the patient is still alive and in good health with no evidence of recurrence.

Effects of chronic treatment with the new ultra-long-acting ß2 -adrenoceptor agonist indacaterol alone or in combination with the ß1 -adrenoceptor blocker metoprolol on cardiac remodelling.

BACKGROUND AND PURPOSE: The ability of a chronic treatment with indacaterol, a new ultra-long-acting ß2 -adrenoceptor agonist, to reverse cardiac remodelling and its effects in combination with metoprolol, a selective ß1 -adrenoceptor antagonist, were investigated on myocardial infarction in a rat model of heart failure (HF). EXPERIMENTAL APPROACH: We investigated the effects of indacaterol and metoprolol, administered alone or in combination, on myocardial histology, ß-adrenoceptor-mediated pathways, markers of remodelling and haemodynamic parameters in a rat model of HF. Five groups of rats were assessed: sham-operated rats; HF rats; HF + indacaterol 0.3 mg·kg(-1) ·day(-1) ; HF + metoprolol 100 mg·kg(-1) ·day(-1) ; HF + metoprolol + indacaterol. All pharmacological treatments continued for 15 weeks. KEY RESULTS: Treatment with either indacaterol or metoprolol significantly reduced the infarct size in HF rats. However, the combination of indacaterol and metoprolol reduced the infarct size even further, reduced both BP and heart rate, reversed the decrease in ejection fraction, normalized left ventricular systolic and diastolic internal diameters, normalized the decreased ß1 adrenoceptor mRNA expression as well as cardiac cAMP levels and reduced cardiac GPCR kinase 2 expression, compared with the untreated HF group. CONCLUSION AND IMPLICATIONS: The results of our study demonstrated an additive interaction between indacaterol and metoprolol in normalizing and reversing cardiac remodelling in our experimental model of HF. The translation of these findings to clinical practice might be of interest, as this combination of drugs could be safer and more effective in patients suffering from HF and COPD.

Effects of sildenafil on the gastrocnemius and cardiac muscles of rats in a model of prolonged moderate exercise training.

Moderate exercise training improves energetic metabolism, tissue perfusion and induces cardiac and skeletal muscle remodeling. Sildenafil, a potent phosphodiesterase-5 inhibitor used to treat erectile dysfunction, reduces infarct size and increases tissue oxygenation in experimental models of cardiovascular disease. We have evaluated the effects of prolonged moderate exercise training and a repeat administration of sildenafil on the rat gastrocnemius and cardiac muscles. Animals were divided into two groups: sedentary and trained. Each group was subdivided into animals treated with vehicle or with two doses of sildenafil (10 or 15 mg/kg/day) during the last week of training. Physical exercise did not induce cardiac hypertrophy, whereas it increased mRNA levels of the PGC-1α, HIF-1α and VEGF genes, which are involved in mitochondrial biogenesis and angiogenesis, and reduced mRNA levels of FoxO3a, MuRF-1 and Atrogin-1. Sildenafil dose-dependently promoted both angiogenesis, as shown by increased capillary density, and muscle atrophy, as shown by muscle fibre size. These effects were more pronounced in trained animals. Our data confirm the beneficial effects of a moderate and prolonged training on cardiovascular and skeletal systems and document the positive and negative effects of sildenafil on these tissues at doses higher than those used in clinical practice. This report may impact on the use of sildenafil as a substance able to influence sports performance.

PPARα mediates the anti-inflammatory effect of simvastatin in an experimental model of zymosan-induced multiple organ failure.

BACKGROUND AND PURPOSE: Zymosan-induced non-septic shock is a multi-factorial pathology that involves several organs including the kidneys, liver and lungs. Its complexity and diversity presents a continuing therapeutic challenge. Given their pleiotropic effect, statins could be beneficial in non-septic shock. One of the molecular mechanisms underlying the anti-inflammatory effect of statins involves the peroxisome proliferator-activated receptor (PPAR) α. We used a zymosan-induced non-septic shock experimental model to investigate the role of PPARα in the anti-inflammatory effects of simvastatin. EXPERIMENTAL APPROACH: Effects of simvastatin (5 or 10 mg·kg(-1) i.p.) were analysed in PPARα knock-out (KO) and PPARα wild type (WT) mice after zymosan or vehicle administration. Organ injury in lung, liver, kidney and intestine was evaluated by immunohistology. PPARα mRNA expression and nuclear factor-κB activation were evaluated in all experimental groups, 18 h after study onset. Cytokine levels were measured in plasma, and nitrite/nitrate in plasma and peritoneal exudate. Nitric oxide synthase, nitrotyrosine and poly ADP-ribose were localized by immunohistochemical methods. KEY RESULTS: Simvastatin significantly and dose-dependently increased the zymosan-induced expression of PPARα levels in all tissues analysed. It also dose-dependently reduced systemic inflammation and the organ injury induced by zymosan in lung, liver, intestine and kidney. These effects were observed in PPARαWT mice and in PPARαKO mice. CONCLUSIONS AND IMPLICATIONS: Simvastatin protected against the molecular and cellular damage caused by systemic inflammation in our experimental model. Our results also provide new information regarding the role of PPARα in the anti-inflammatory effects of statins.

Hyperbaric oxygen therapy reduces the toll-like receptor signaling pathway in multiple organ failures.

PURPOSE: Zymosan-induced generalized inflammation is the only experimental model that reproduces characteristics of human multiple organ dysfunction syndrome (MODS). Toll-like receptors (TLRs) are key components in innate immune responses and their signaling pathway is known to activate target genes such as nuclear factor-κB (NF-κB) and cytokines that are involved in inflammation and immune responses. We previously reported that hyperbaric oxygen (HBO) therapy is effective in the treatment of severe zymosan-induced inflammation in MODS. The aim of this study was to investigate the effect of HBO exposure on TLR2 and TLR4 signal transduction and organ dysfunction during MODS induced by zymosan in the rat. METHODS: Male Wistar rats were randomized into four groups and treated as follows: (1) saline solution (control); (2) zymosan; (3) HBO 4 and 11 h after zymosan injection; (4) HBO 4 and 11 h after saline solution injection. Zymosan-induced damage of the lungs, liver, and small intestine was evaluated using histology and biochemistry. The activation of the TLR signaling pathway was measured with Western blot, reverse transcriptase polymerase chain reaction analysis (RT-PCR), and immunohistochemistry. RESULTS: Zymosan induced a severe inflammatory response characterized by the activation of the TLR signaling pathway and by an organ dysfunction. HBO exposure significantly reduced the development of lung, liver, and intestine injury in our experimental model. It also significantly reduced the zymosan-induced expression of TLR2 and TLR4, NF-κB activation, and cytokine production. CONCLUSIONS: Taken together, these results suggest that, by interfering with the TLR pathway, HBO treatment may exert a protective effect against tissue injury caused by zymosan-induced generalized inflammation.