Cardiotrophin-1 in Asymptomatic Hypertensive Patients With Mild Diastolic Dysfunction: Potential Prognostic Value in Early Stages of Hypertensive Heart Disease.

BACKGROUND: Regardless of the advancements in modern technology and treatment options, heart failure (HF) exhibits impervious mortality and morbidity rates. Arterial hypertension poses one of the greatest risks for developing HF, yet the exact pathophysiological path and changes that lead from isolated hypertension to HF are still unclear. Cardiotrophin-1 (CT-1) serves as a promising prognostic biomarker for the onset of HF in hypertensive patients. The aim of this study was to investigate whether CT-1 levels are elevated in a selected group of asymptomatic hypertensive patients. METHODS: In a selected cohort of 40 asymptomatic patients with early diastolic dysfunction (grade I), without any signs of increased filling pressures in the left ventricle, as well as 20 healthy individuals, the levels of CT-1 brain natriuretic peptide (BNP) along with various echocardiographic parameters were evaluated. RESULTS: The mean age of the hypertensive patients was 56 ± 5 years and 52± 3.5 years for the normotensive controls. The hypertensive group exhibited higher levels of CT-1, which was not affected by left ventricular hypertrophy. Notably, in patients with normal E/E' < 8 (n = 30), CT-1 levels were 1165 ± 471 pg/ml compared to 2069 ± 576 pg/ml in patients with marginal E/E' > 8 and <14 (n = 10), p = 0.001. CONCLUSIONS: Our study demonstrated elevated CT-1 levels in a cohort of asymptomatic hypertensive patients, exhibiting mild diastolic dysfunction. These findings are suggestive of the potentially prognostic value of this particular biomarker in the early stages of hypertensive heart disease.

Effects of Diet Consistency on Rat Maxillary and Mandibular Growth within Three Generations-A Longitudinal CBCT Study.

BACKGROUND: In this study, wistar rats were used to examine the impact of diet consistency on maxillary and mandibular growth over three generations. METHODS: In this investigation, a breeding sample of 60 female and 8 male wistar rats was used. Measuring was only performed on female animals. The first generation's primary breeding sample consisted of 20 female wistar rats that were 30 days old and 4 male rats that were also 30 days old; two subsequent generations were created from these animals. At the age of 100 days, CBCTs were collected of all male rats. Twenty-eight craniofacial landmarks were selected for the linear measurements on stl format extracted from the DICOM files. A Bonferroni test was performed for the statistical analysis. RESULTS: Means of measurements of all soft diet groups compared to corresponding measurements of the hard diet groups were significantly different. According to linear measurements, there was statistical difference on the maxillary measurements between the soft diet groups of the first and third generation, while the rest did not appear to have any statistical difference. There was significant difference for the mandibular dimensions only when the first generation soft diet group was compared with the third generation soft diet group. CONCLUSIONS: Food consistency has a significant impact on the growth and development of the maxilla and mandible. Soft diet habits may result in retrognathic mandible, and narrower maxilla.

Evaluation of Vitamin D-enriched Bone Graft in Surgically-induced Critical-sized Bone Defects: An Experimental Study.

BACKGROUND: Restoration of bone defects in the craniac vault may require the use of autografts, allografts, xenografts, or synthetic grafts. There are promising data that vitamin D may play a positive role in graft incorporation. The purpose of the present study is the evaluation of the impact of vitamin D addition to human-derived bone grafts in the healing of critical-sized bone defects in porcine skulls. MATERIALS AND METHODS: Four identical critical-sized defects were created in the calvaria of 8 adult Landrace Large White pigs. The first defect was left blank as control, the second defect was filled with human-derived bone graft, the third defect was filled with human-derived bone graft enriched with a low concentration of vitamin D (2 mg/mL), and the fourth defect was filled with human-derived bone graft enriched with a high concentration of vitamin D (10 mg/mL). The animals were sacrificed after 12 weeks. Harvested tissue specimens were qualitatively evaluated by histology. New bone formation (bone volume/tissue volume) was quantitatively measured by histomorphometry. RESULTS: Signs of bone formation were evident in all bone sockets. Mean values of the bone volume/tissue volume of the 4 defects were 10.91%, 11.05%, 10.40% and 10.87% respectively, at 12 weeks. In 5 animals, high concentration of vitamin D caused a significant improvement in bone formation in relation to controls. In 3 animals, a high concentration of vitamin D was associated with decreased bone formation compared with controls. No statistical difference was observed in the graft healing among the 4 graft sites ( P > 0.05). CONCLUSIONS: The results of this study have shown that the addition of vitamin D to human-derived bone grafts does not have a significant effect on bone formation and graft incorporation in critical-sized bone defects of the porcine calvaria. Further high-quality studies are needed to fully elucidate the role of vitamin D in bone formation and bone graft union.

Mechanisms and Therapeutic Approaches for Peritoneal Adhesions: A Comprehensive Review.

Peritoneal adhesions are responsible for several and sometimes severe clinical phenotypes remaining a major problem for many patients today. Adhesions are formed within the peritoneal cavity as a result of surgery, inflammation, or injury and can cause a range of clinical symptoms, including abdominal pain, small bowel obstruction, infertility, and other complications. The incidence of peritoneal adhesions remains high as it is estimated that more than 50% of patients who undergo abdominal surgery will develop adhesions. Although advancements in surgical techniques and perioperative management have been developed, the risk of adhesion formation cannot be eliminated, and thus, the development of effective prevention strategies and treatments remains a priority in the field of surgery. In this review, we summarize the cellular and molecular mechanisms involved in the peritoneal adhesions, but also the experimental therapy approaches that have been investigated toward a solution to their possible clinical phenotypes.

Long-Term Effect of Diet Consistency on Mandibular Growth within Three Generations: A Longitudinal Cephalometric Study in Rats.

BACKGROUND: This study investigated the effect of diet consistency on mandibular growth of Wistar rats through three generations. METHODS: A total breeding sample of 60 female and 8 male Wistar rats were used in this study. Measurements took place only on female animals. Twenty female Wistar rats at 30 days old and four male rats at 30 days old comprised the primary breeding sample of the first generation, and from these animals two different generations were reproduced. Lateral cephalometric X-rays were taken from all female rats at the age of 100 days. A total of 7 craniofacial landmarks were selected for the linear measurements, and 12 curves and 90 landmarks were selected for geometric morphometric analysis of the lateral X-rays. Bonferroni test and a permutation test were performed for the statistical analysis. RESULTS: Means of measurements of all soft diet groups compared to hard diet groups were significantly smaller. According to linear measurements, there was a significant difference only between the first-generation soft diet with the third-generation soft diet group. According to geometric morphometric analysis, the statistical differences appeared on the condylar process and the angle of the mandible. CONCLUSIONS: The soft diet could be responsible for less mandibular growth, and this information might be passing through generations.

Effects of Incretin Pathway Elements on Bone Properties.

Introduction The effects of incretin-based drugs, such as receptor agonists of glucagon-like peptide-1 and inhibitors of dipeptidyl peptidase-4, on bone metabolism are not completely clear yet. The aim of this study is to compare the effects of glucagon-like peptide-1 and inhibitors of dipeptidyl peptidase-4 on the bone to see how different elements of the incretin pathway affect bone quality in terms of biomechanical properties, bone turnover, and mineral properties. Materials and methods Forty 10-week-old Wistar rats were divided into four groups: a control group, a control diabetic group, a diabetic group treated with sitagliptin, and a diabetic group treated with exenatide. Type 2 diabetes was simulated by dietary manipulation in addition to low-dose streptozotocin, and then two different incretin-based drugs were administered. The rats were sacrificed after five weeks of therapeutic treatment. Their serum was analyzed with the enzyme-linked immunosorbent assay (ELISA) method for basic bone turnover markers, and their right femur was subjected to a three-point bending test. Finally, Hematoxylin & Eosin staining, in addition to Raman spectroscopy, were employed to access the collagen and mineral properties of the bone. Results Both incretin-based drugs reduced osteoclast function; however, they were not able to restore osteoblastic function to normal. The net effect on bone strength was surprising: bone elasticity was restored by the antidiabetic treatment, but bone strength deteriorated. Exenatide had a slightly more pronounced effect, which, although not significant, points to the direction that dipeptidyl peptidase-4 (DPP4) may be a linking factor between reduced osteoclastic function and reduced bone formation, as suggested by the literature. Conclusion DPP4 receptors seem to be one of the links between reduced osteoclast function and reduced bone remodeling, so DPP4 inhibition can be more detrimental to the bone than glucagon-like peptide-1 (GLP-1) receptor agonists.

The Role of MicroRNA-126 in Atherosclerotic Cardiovascular Diseases.

Atherosclerotic cardiovascular diseases remain the leading cause of morbidity and mortality worldwide despite all efforts made towards their management. Other than targeting the traditional risk factors for their development, scientific interest has been shifted towards epigenetic regulation, with microRNAs (miRs) being at the forefront. MiR-126, in particular, has been extensively studied in the context of cardiovascular diseases. Downregulated expression of this miR has been associated with highly prevalent cardiovascular risk factors such as arterial hypertension and diabetes mellitus. At the same time, its diagnostic and prognostic capability concerning coronary artery disease is still under investigation, with up-to-date data pointing towards a dysregulated expression in a stable disease state and acute myocardial infarction. Moreover, a lower expression of miR-126 may indicate a higher disease complexity, as well as an increased risk for future major adverse cardiac and cerebrovascular events. Ultimately, overexpression of miR-126 may emerge as a novel therapeutic target in atherosclerotic cardiovascular diseases due to its potential in promoting therapeutic angiogenesis and anti-inflammatory effects. However, the existing challenges in miR therapeutics need to be resolved before translation to clinical practice.

Platelet-Rich Plasma for Pleurodesis: An Experimental Study in Rabbits.

Background and Objectives: This study was designed to evaluate platelet-rich plasma (PRP) as a method of pleurodesis in a rabbit model. Pleurodesis with PRP was compared against the gold-standard use of talc. The secondary evaluation assessed the ideal time for achieving pleurodesis. Materials and Methods: 25 healthy New Zealand white rabbits were assigned to three groups, as follows: 12 animals in the first and second groups, as well as one animal with no intervention in the final group, which was used as a control. The talc pleurodesis group (baseline) underwent pleurodesis with sterile talc, which is the gold-standard sclerosing agent used for pleurodesis. The PRP group underwent pleurodesis using autologous PRP. The last group had one rabbit with no intervention. A total of 12 rabbits (n = 6 for the talc pleurodesis group and n = 6 for the PRP group) were sacrificed 3 days (72 h) after the intervention, and 12 rabbits (n = 6 for the talc pleurodesis group and n = 6 for the PRP group) were sacrificed 6 days (144 h) after the intervention. In both the talc and PRP group, FBC and CRP were measured before the intervention and in 3 or 6 days afterwards, respectively. The pleura and the lungs were evaluated histopathologically. Results: Macroscopically, there were no statistically significant differences between the two groups. In terms of microscopic findings, there were no statistically significant differences in inflammatory reactions provoked in the visceral and parietal pleura between the PRP and talc. In addition, with talc pleurodesis, a foreign-body reaction was observed in about 50% of the cases, which was not observed with PRP. In terms of inflammation between 3 and 6 days, there were no statistically significant differences with PRP, there was only a statistically significant difference between 3 and 6 days regarding the parietal pleura in the talc group. Conclusions: The instillation of autologous PRP in the pleural cavity shows promise in achieving pleurodesis. The efficacy of PRP as a pleurodesis agent should be examined further.

Platelet-rich Plasma Gel versus Hyaluronic Acid on Prevention of Peritoneal Abdominal Adhesion Formation in Rats.

Background: Intra-abdominal adhesion formation is still unavoidable and a cause of significant morbidity in abdominal surgery. Platelet-rich plasma gel and hyaluronic acid have been studied for their protective of therapeutic effects on adhesions. The aim of the present study is to compare Platelet-rich plasma and hyaluronic acid in adhesion prevention. Material and method: Twenty-seven Sprague-Dawley rats were randomly allocated into three equal groups(n=9). Surgical trauma was used to induce adhesion formation. After trauma, 1 ml normal saline was instilled in the peritoneal cavity in control group (n=9), 1 ml liquid Hyaluronic acid (25 mg/ml) was instilled in group A (n= 9) and 1 ml of platelet-rich plasma was instilled in group B (n = 9). Four weeks after the laparotomy, a repetitive laparotomy was performed and adhesions were examined microscopically and macroscopically. Results: Platelet-rich plasma gel and hyaluronic acid both reduce the extent and grade of adhesions macroscopically. Interestingly, PRP turns out to be superior in the reduction of tenacity and adhesion area. Moreover, platelet-rich plasma ameliorates abdominal adhesion formation by reducing neutrophils, fibrosis, and inflammation. Conclusion: The results indicate that platelet-rich plasma gel surpasses hyaluronic acid in abdominal adhesion prevention.

Angiogenic and Inflammatory Alterations of Endometriotic Lesions in a Transgenic Animal Experimental Model With Loss of Expression of PPAR-Alpha Receptors.

INTRODUCTION: Peroxisome proliferator-activated receptors (PPARs) have been proposed as a medical treatment against endometriosis in preclinical and clinical studies. Their effect seems to be triggered through the suppression of angiogenesis. In the present study, we used a transgenic animal model with a loss of expression of PPAR-alpha receptors to examine their effect on the course of surgically induced endometriotic lesions. METHODS: Ten C57BL/6 mice that served as controls and 10 B6;129S4-PPARatm1Gonz/J t transgenic mice characterized by absolute loss of expression of PPAR-alpha receptors were used for induction of endometriosis with a previously described surgical technique. RESULTS: Five animals (50%) exhibited abundant endometriotic crypts in the control group whereas only one (10%) animal in the transgenic experimental group had a similar pathological image. Neo-vascularization significantly differed among the two groups (p=0.034) favoring the control group as it was extremely limited in half of the PPAR-alpha null animals. The median inflammation score was 2.5 (1-4) in the P B6;129S4-PPARatm1Gonz/J group, whereas it was minimal, 1 (0-2), in the C57BL/6 group. However, these differences were not statistically significant (p=0.101). The fibroblastic activity was also very limited in the PPAR-alpha-deficient model, whereas animals belonging to the control group exhibited an intermediate increase of this index (p=0.022). CONCLUSION: Surgically induced endometriotic implants in animals with loss of expression of PPAR-alpha receptors exhibit significant differences in their pathology compared to lesions induced in control animals. This information suggests that PPAR-alpha receptors have a significant impact on the course of the disease, indicating that they may serve as potential targets for future medical therapies.

Effect of Aromatase Inhibitors on Serum Calprotectin Levels in an Animal Experimental Model: Trial.

BACKGROUND/AIM: Utilizing an experimental animal model, we investigated the correlation between aromatase inhibitors (AIs) (anastrozole and letrozole) and Calprotectin levels. AIs have demonstrated superior efficacy when used as adjuvant endocrine therapy or monotherapy for postmenopausal patients with hormone receptor (HR)-positive early-stage breast cancer, although various side effects have been recorded. MATERIALS AND METHODS: Fifty-five adult female Wistar rats were randomized and assigned into four groups. The control group received no intervention. The other three groups were subjected to ovariectomy, and serum Calprotectin levels were measured at baseline, 2, and 4 months. In addition, glucose, total cholesterol, very low-density lipoprotein- (VLDL-) cholesterol, low-density lipoprotein (LDL-) cholesterol, high-density lipoprotein- (HDL-) cholesterol, and triglyceride levels were measured. Histological analysis of liver tissue was carried out following rats' euthanasia. RESULTS: Aromatase inhibitors (anastrozole and letrozole) affect calprotectin levels in ovariectomized rats. Calprotectin, a marker of inflammation, was found to be affected by the use of the inhibitors. CONCLUSION: The potential of hepatotoxicity can be examined by assessing the elevation of inflammation markers such as Calprotectin, which is an indicator that should be strictly taken into consideration when administering aromatase inhibitors as treatment.

Histological and Biochemical Analysis after Posterior Mandibular Displacement in Rats.

The present study aimed to investigate any biochemical and histological changes of the rat condyle and mandible in animals that had sustained mandibular growth restriction. Seventy-two male Wistar rats were divided into two equal groups, experimental and control. Each group consisted of three equal subgroups. The animals were sacrificed 30, 60, and 90 days after the start of the experiment. Blood samples were collected from the eye, and the osteoprotegerin (OPG), Receptor Activator of Nuclear Factor Kappa B Ligand (RANKL), and Macrophage Colony-Stimulating factor (MCSF)concentrations were measured by using enzyme-linked immunosorbent assay (ELISA) kits. A histological analysis was performed on the mandibular condyles. The blood serum values of OPG, RANKL, and MCSF did not exhibit any statistically significant difference between groups or subgroups. However, significant histological changes became evident after a histomorphometric condylar examination was performed. The Bone Surface/Total Surface ratio appeared reduced in the anterior and posterior regions of the condyle. In addition, the Posterior Condylar Cartilage Thickness was measured and determined to be significantly diminished. The present intervention that employed orthodontic/orthopedic devices did not prove to have any significant effect on the circulating proteins under study. Posterior displacement of the mandible may culminate only in local histological alterations in condylar cartilage thickness and its osseous microarchitecture.

Granulocyte Colony-Stimulating Factor Ameliorates Endothelial Activation and Thrombotic Diathesis Biomarkers in a Murine Model of Hind Limb Ischemia.

Novel therapies in peripheral arterial disease, such as granulocyte colony-stimulating factor (GCSF) administration, might result in anti-atherosclerotic effects. In this study, we used 10-week-old male ApoE-/- mice, which were fed an atherosclerosis-inducing diet for four weeks. At the end of the four weeks, hind limb ischemia was induced through left femoral artery ligation, the atherosclerosis-inducing diet was discontinued, and a normal diet was initiated. Mice were then randomized into a control group (intramuscular 0.4 mL normal saline 0.9% for 7 days) and a group in which GCSF was administrated intramuscularly in the left hind limb for 7 days (100 mg/kg). In the GCSF group, but not in the control group, we observed significant reductions in the soluble adhesion molecules (vascular cell adhesion molecule-1 (sVCAM-1) and intercellular adhesion molecule-1 (sICAM-1)), sE-Selectin, and plasminogen activator inhibitor (PAI)-1 when they were measured through ELISA on the 1st and the 28th days after hind limb ischemia induction. Therefore, GCSF administration in an atherosclerotic mouse model of hind limb ischemia led to decreases in the biomarkers associated with endothelial activation and thrombosis. These findings warrant further validation in future preclinical studies.

Epicardial Adipose Tissue as an Independent Cardiometabolic Risk Factor for Coronary Artery Disease.

During the last decades, visceral adiposity has been at the forefront of scientific research because of its complex role in the pathogenesis of cardiovascular diseases. Epicardial adipose tissue (EAT) is the visceral lipid compartment between the myocardium and the visceral pericardium. Due to their unobstructed anatomic vicinity, epicardial fat and myocardium are nourished by the same microcirculation. It is widely known that EAT serves as an energy lipid source and thermoregulator for the human heart. In addition to this, epicardial fat exerts highly protective effects since it releases a great variety of anti-inflammatory molecules to the adjacent cardiac muscle. Taking into account the unique properties of human EAT, it is undoubtedly a key factor in cardiac physiology since it facilitates complex heart functions. Under pathological circumstances, however, epicardial fat promotes coronary atherosclerosis in a variety of ways. Therefore, the accurate estimation of epicardial fat thickness and volume could be utilized as an early detecting method and future medication target for coronary artery disease (CAD) elimination. Throughout the years, several therapeutic approaches for dysfunctional human EAT have been proposed. A balanced healthy diet, aerobic and anaerobic physical activity, bariatric surgery, and pharmacological treatment with either traditional or novel antidiabetic and antilipidemic drugs are some of the established medical approaches. In the present article, we review the current knowledge regarding the anatomic and physiological characteristics of epicardial fat. In addition to this, we describe the pathogenic mechanisms which refer to the crosstalk between epicardial fat alteration and coronary arterial atherosclerosis development. Lastly, we present both lifestyle and pharmacological methods as possible treatment options for EAT dysfunction.

Effect of Diet Consistency on Rat Mandibular Growth: A Geometric Morphometric and Linear Cephalometric Study.

BACKGROUND: Our study intended to investigate the null hypothesis that there is no effect of diet consistency on rat mandibular growth. METHODS: A total sample of 24 female wistar rats, 30 days old, was used in this study. In the first group, the rats were fed soft diet and in the second group, they were fed hard diet for 60 days. On the 60th day, the rats were sedated and lateral cephalometric X-rays were taken. Lateral cephalometric X-rays were digitized with 7 craniofacial landmarks for the linear measurements, as well as with 12 curves and 90 landmarks, of which 74 were semilandmarks and 16 were fixed landmarks for morphometric analysis. These landmarks were exposed to Procrustes superimposition and Principal Component Analysis (PCA) to describe the shape variability of the mandible. RESULTS: Means measurements of the soft diet group compared to those of the hard diet group were significantly different in linear and morphometric analysis measurements. The soft diet group of wistar rats revealed significant changes on the condyle (smaller), the angle of the mandible, and on the body of the mandible. CONCLUSIONS: Diet consistency affects the craniofacial growth of rats. Soft diet could be responsible for less mandibular growth.

Peroxisome Proliferator-Activated Receptor Alpha (PPAR-α) as a Regulator of the Angiogenic Profile of Endometriotic Lesions.

Endometriosis is a disease that affects a significant proportion of women and its infiltrative pattern is entirely dependent on the vascular supply of lesions. Several factors seem to trigger the process of angiogenesis in endometriotic lesions. During the last years, peroxisome proliferator-activated receptors (PPARs), a group of nuclear proteins that regulate gene transcription and that seem to regulate energy consumption and expenditure, have been also implicated in the pathophysiology of angiogenesis. Their ability to regulate the course of cancer and improve the survival rates of patients has been extensively studied and seems to be partially dependent on alteration of the vascular supply of malignant lesions. Research in the field of endometriosis is scarce in the international literature and mainly focused on PPAR-gamma. However, indirect evidence suggests that PPAR-alpha (PPAR-α) may also regulate the vascular supply of endometriotic lesions as well. Specifically, PPAR-α agonists seem to downregulate angiogenesis by increasing the expression of several anti-angiogenic molecules, including thrombospondin-1 (TSP-1) and gypenoside 140 (gp140), as well as factors that are involved in the mitogen-activated protein kinase cascade. In the present article, we summarize existing indirect and direct evidence that indicates the existence of an association between the expression of PPAR-α and endometriosis to help future research in this field.

Epicardial Adipocyte-derived TNF-α Modulates Local Inflammation in Patients with Advanced Coronary Artery Disease.

BACKGROUND: Epicardial Adipose Tissue (EAT) surrounds the epicardium and can mediate harmful effects related to Coronary Artery Disease (CAD). OBJECTIVE: We explored the regional differences between adipose stores surrounding diseased and non-diseased segments of coronary arteries in patients with advanced CAD. METHODS: We enrolled 32 patients with known CAD who underwent coronary artery bypass graft (CABG) surgery. Inflammatory mediators were measured in EAT biopsies collected from a region of the Left Anterior Descending Artery (LAD) with severe stenosis (diseased segment) and without stenosis (non-diseased segment). RESULTS: Mean age was 64.3±11.1 years, and mean EAT thickness was 7.4±1.9 mm. Dyslipidemia was the most prevalent comorbidity (81% of the patients). Out of a total of 11 cytokines, resistin (p=0.039), matrix metallopeptidase 9 (MMP-9) (p=0.020), C-C motif chemokine ligand 5 (CCL-5) (p=0.021), and follistatin (p=0.038) were significantly increased in the diseased compared with the non-diseased EAT segments. Indexed tumor necrosis factor-alpha (TNF-α), defined as the diseased to non-diseased cytokine levels ratio, was significantly correlated with increased EAT thickness both in the whole cohort (p=0.043) and in a subpopulation of patients with dyslipidemia (p=0.009). Treatment with lipid-lowering agents significantly decreased indexed TNF-α levels (p=0.015). No significant alterations were observed in the circulating levels of these cytokines with respect to CAD-associated comorbidities. CONCLUSION: Perivascular EAT is a source of cytokine secretion in distinct areas surrounding the coronary arteries in patients with advanced CAD. Adipocyte-derived TNF-α is a prominent mediator of local inflammation.

The Effect of MicroRNA-126 Mimic Administration on Vascular Perfusion Recovery in an Animal Model of Hind Limb Ischemia.

Background: MicroRNAs have been linked to angiogenesis and could prove to be valuable future therapeutic targets in ischemic cardiovascular diseases. Methods: Ten-week-old male C57Bl/6 mice were subjected to left femoral artery ligation and were treated with microRNA-126 mimic at a dose of 5 mg/kg (Group A, n = 10) or 5 mg/kg microRNA mimic negative control (Group B, n = 10) on days 1, 3, and 7. Laser Doppler imaging was performed to verify successful ligation on day 0 and to evaluate differences in the ischemic-to-normal (I/N) hind limb perfusion ratio on day 28. Muscle tissue expression of microRNA-126 and vascular endothelial growth factor (VEGF) was determined via PCR. Results: Following microRNA-126 mimic administration in Group A subjects, we noted a stepwise increase in I/N hind limb perfusion ratio (Day 0: 0.364 ± 0.032 vs. Day 8: 0.788 ± 0.049 vs. Day 28: 0.750 ± 0.039, p = 0.001). In Group B a stepwise increase in I/N hind limb perfusion ratio was observed (Day 0: 0.272 ± 0.057 vs. Day 8: 0.382 ± 0.020 vs. Day 28: 0.542 ± 0.028, p = 0.074). Muscle tissue expression of microRNA-126 in the ischemic hind limb of Group A was 350-fold lower compared to the ischemic hind limb of Group B (p < 0.001). A higher expression (14.2-fold) of VEGF in the ischemic hind limb of microRNA-126-treated mice compared to that of control group was detected (p < 0.001). A statistically significant negative correlation was noted between microRNA-126 and VEGF tissue expression levels in the ischemic limbs of the entire study population. Conclusion: MicroRNA-126 delivery in the ischemic hind limb of mice improved vascular perfusion with VEGF upregulation.

The impact of proangiogenic microRNA modulation on blood flow recovery following hind limb ischemia. A systematic review and meta-analysis of animal studies.

BACKGROUND: Pro-angiogenic microRNA modulation is a potentially attractive approach in the management of peripheral artery disease (PAD). The aim of this systematic review and meta-analysis was to examine the impact of microRNAs involved in the process of angiogenesis on blood flow recovery following hind limb ischemia induction in animal models. METHODS: A literature search was performed to identify studies testing the efficacy of microRNA treatment on animal models of hind limb ischemia. Following that, a meta-analysis of the included studies was executed with the primary outcome being the change in ischemic-to-normal hind limb perfusion ratio assessed via laser Doppler imaging. Moreover, risk of bias, sensitivity analysis and publication bias were evaluated. RESULTS: Studies evaluation led to the inclusion of 18 studies whose meta-analysis suggested that microRNA treatment resulted in improved ischemic hind limb perfusion 7 [standardized mean difference (SMD): 0.93, 95% CI 0.49-1.38], 14 (SMD: 1.31, 95% CI 0.78-1.84), and 21 days (SMD: 1.13, 95% CI 0.59-1.66) after hind limb ischemia induction. Moderate-to-substantial heterogeneity and possible publication bias were noted. Risk of bias was unclear despite the balanced baseline animal characteristics. CONCLUSION: The present meta-analysis suggests that pro-angiogenic modulation of microRNAs accelerates vascular perfusion recovery in animal models of acute hind limb ischemia. Further studies on animal models with similar characteristics to that of PAD patients are warranted to translate those findings in human PAD setting.

The Modulating Effect of Ursodeoxycholic Acid on Liver Tissue Cyclooxygenase-2 Expression Following Extended Hepatectomy.

INTRODUCTION: Hepatic regeneration is a complex process involving a multitude of well-timed molecular operations. Ursodeoxycholic acid (UDCA) is postulated to exert a protective effect against oxidative stress and enzymatic degradation of the extracellular matrix, in turn potentiating the regenerative response. The aim of the present animal study is to evaluate the impact of UDCA administration in liver tissue expression of cyclooxygenase-2 (COX-2) in a setting of acute liver failure achieved by 80% hepatectomy. MATERIALS AND METHODS: Twenty-four adult male Sprague-Dawley rats were randomly assigned to an experimental (UDCA) and a control group. Animals in the UDCA received oral pretreatment with UDCA for 14 days via feeding tube, while animals in the control group received saline. All animals underwent resection of approximately 80% of the liver parenchyma. Tissue and blood sample collection were performed 48 hours postoperatively. RESULTS: The postoperative mitotic index and Ki-67 levels were found to be elevated in the UDCA group (43±11.4 and 13.7±24.7 versus 31±16.7 and 7.6±5.7), albeit without any statistical significance. Pretreatment with UDCA significantly decreased COX-2 expression levels (p=0.28) as well as serum tumor necrosis factor α (TNFα) levels (37.3±10.9 pg/mL versus 75.4±14.4 pg/mL, p=0.004). COX-2 expression score was observed to be weakly correlated to Ki-67 levels in both groups. Although COX-2 expression score was not correlated with serum TNFα levels in the control group, animals pretreated with UDCA exhibited moderate correlation (r=0.45). CONCLUSION: Preoperative administration of UDCA exerts a suppressive effect on tissue expression of COX-2 following 80% hepatectomy and enforces a positive correlation between COX-2 and serum TNFα levels, suggesting that UDCA preconditions liver tissue to display an enhanced regenerative response to circulating cytokines, most notably TNFα. The weak association of COX-2 with Ki-67 expression levels suggests that COX-2 may be of secondary importance during the early phases of liver regeneration.