Placental chorionic plate-derived mesenchymal stem cells ameliorate severe acute pancreatitis by regulating macrophage polarization via secreting TSG-6.

BACKGROUND: Mesenchymal stem cells (MSCs) hold promising potential to treat systemic inflammatory diseases including severe acute pancreatitis (SAP). In our previous study, placental chorionic plate-derived MSCs (CP-MSCs) were found to possess superior immunoregulatory capability. However, the therapeutic efficacy of CP-MSCs on SAP and their underlying mechanism remain unclear. METHODS: The survival and colonization of exogenous CP-MSCs were observed by bioluminescence imaging and CM-Dil labeling in rodent animal models of SAP. The therapeutic efficacy of CP-MSCs on SAP rats was evaluated by pathology scores, the levels of pancreatitis biomarkers as well as the levels of inflammatory factors in the pancreas and serum. The potential protective mechanism of CP-MSCs in SAP rats was explored by selectively depleting M1 or M2 phenotype macrophages and knocking down the expression of TSG-6. RESULTS: Exogenous CP-MSCs could survive and colonize in the injured tissue of SAP such as the lung, pancreas, intestine, and liver. Meanwhile, we found that CP-MSCs alleviated pancreatic injury and systemic inflammation by inducing macrophages to polarize from M1 to M2 in SAP rats. Furthermore, our data suggested that CP-MSCs induced M2 polarization of macrophages by secreting TSG-6, and TSG-6 played a vital role in alleviating pancreatic injury and systemic inflammation in SAP rats. Notably, we found that a high inflammation environment could stimulate CP-MSCs to secrete TSG-6. CONCLUSION: Exogenous CP-MSCs tended to colonize in the injured tissue and reduced pancreatic injury and systemic inflammation in SAP rats through inducing M2 polarization of macrophages by secreting TSG-6. Our study provides a new treatment strategy for SAP and initially explains the potential protective mechanism of CP-MSCs on SAP rats.

Abdominal paracentesis drainage ameliorates myocardial injury in severe experimental pancreatitis rats through suppressing oxidative stress.

BACKGROUND: Abdominal paracentesis drainage (APD) is a safe and effective strategy for severe acute pancreatitis (SAP) patients. However, the effects of APD treatment on SAP-associated cardiac injury remain unknown. AIM: To investigate the protective effects of APD on SAP-associated cardiac injury and the underlying mechanisms. METHODS: SAP was induced by 5% sodium taurocholate retrograde injection in Sprague-Dawley rats. APD was performed by inserting a drainage tube with a vacuum ball into the lower right abdomen of the rats immediately after SAP induction. Morphological staining, serum amylase and inflammatory mediators, serum and ascites high mobility group box (HMGB) 1, cardiac-related enzymes indexes and cardiac function, oxidative stress markers and apoptosis and associated proteins were assessed in the myocardium in SAP rats. Nicotinamide adenine dinucleotide phosphate oxidase activity and mRNA and protein expression were also examined. RESULTS: APD treatment improved cardiac morphological changes, inhibited cardiac dysfunction, decreased cardiac enzymes and reduced cardiomyocyte apoptosis, proapoptotic Bax and cleaved caspase-3 protein levels. APD significantly decreased serum levels of HMGB1, inhibited nicotinamide adenine dinucleotide phosphate oxidase expression and ultimately alleviated cardiac oxidative injury. Furthermore, the activation of cardiac nicotinamide adenine dinucleotide phosphate oxidase by pancreatitis-associated ascitic fluid intraperitoneal injection was effectively inhibited by adding anti-HMGB1 neutralizing antibody in rats with mild acute pancreatitis. CONCLUSION: APD treatment could exert cardioprotective effects on SAP-associated cardiac injury through suppressing HMGB1-mediated oxidative stress, which may be a novel mechanism behind the effectiveness of APD on SAP.

MicroRNAs in acute pancreatitis: From pathogenesis to novel diagnosis and therapy.

Acute pancreatitis (AP) is an inflammatory disorder initiated by activation of pancreatic zymogens, leading to pancreatic injury and systemic inflammatory response. MicroRNAs (miRNAs) have emerged as important regulators of gene expression and key players in human physiological and pathological processes. Discoveries over the past decade have confirmed that altered expression of miRNAs is implicated in the pathogenesis of AP. Indeed, a number of miRNAs have been found to be dysregulated in various cell types involved in AP such as acinar cells, macrophages, and lymphocytes. These aberrant miRNAs can regulate acinar cell necrosis and apoptosis, local and systemic inflammatory response, thereby contributing to the initiation and progression of AP. Moreover, patients with AP possess unique miRNA signatures when compared with healthy individuals or those with other diseases. In view of their stability and easy detection, therefore, miRNAs have the potential to act as biomarkers for the diagnosis and assessment of patients with AP. In this review, we provide an overview of the novel cellular and molecular mechanisms underlying the roles of miRNAs during the disease processes of AP, as well as the potential diagnosis and therapeutic biomarkers of miRNAs in patients with AP.

An efficient protocol to generate placental chorionic plate-derived mesenchymal stem cells with superior proliferative and immunomodulatory properties.

BACKGROUND: Placenta-derived MSCs (P-MSCs) represent a promising tool for cell-based therapeutic applications. However, the increasing demand for P-MSCs in clinical trials makes high quality and large number of P-MSCs mandatory. Here, we aim to develop an efficient protocol for P-MSC isolation and culture. METHODS: The modified explant culture (MEC) method by combining an initial mild enzymatic reaction with the subsequent explant culture was developed to simultaneously produce various P-MSCs from the different regions of the placenta in serum-free medium (SFM). Its isolation efficiencies, cell yield, and proliferative capacity were compared with the conventional explant culture (EC) method. Furthermore, we determined whether functional properties of P-MSCs are affected by the used tissue-harvesting sites in terms of their proliferation, migration, and the immunomodulatory effect on macrophage. RESULTS: The MEC method achieved higher yield and shorter time in primary cell confluence in SFM compared with the conventional method. The harvested cells possessed the MSC characteristics and demonstrated significantly stronger proliferation ability. Importantly, MSCs derived from chorionic plate (CP-MSCs) were found to exhibit superior properties to the other P-MSCs in proliferation and migration capacity, maintaining the fetal origin over serial passages. Notably, CP-MSCs show stronger ability in regulating macrophage polarization from M1 to M2. CONCLUSION: Our study developed an efficient and high-yield technique to produce high-quality P-MSCs from the placenta, hence serving as an optimal source of MSCs for clinical application.

NADPH Oxidase Hyperactivity Contributes to Cardiac Dysfunction and Apoptosis in Rats with Severe Experimental Pancreatitis through ROS-Mediated MAPK Signaling Pathway.

NADPH oxidase (Nox) is considered a major source of reactive oxygen species (ROS) in the heart in normal and pathological conditions. However, the role of Nox in severe acute pancreatitis- (SAP-) associated cardiac injury remains unclear. Therefore, we aim to investigate the contribution of Nox to SAP-associated cardiac injury and to explore the underlying molecular mechanisms. Apocynin, a Nox inhibitor, was given at 20 mg/kg for 30 min before SAP induction by a retrograde pancreatic duct injection of 5% sodium taurocholate. Histopathological staining, Nox activity and protein expression, oxidative stress markers, apoptosis and associated proteins, cardiac-related enzyme indexes, and cardiac function were assessed in the myocardium in SAP rats. The redox-sensitive MAPK signaling molecules were also examined by western blotting. SAP rats exhibited significant cardiac impairment along with increased Nox activity and protein expression, ROS production, cell apoptosis, and proapoptotic Bax and cleaved caspase-3 protein levels. Notably, Nox inhibition with apocynin prevented SAP-associated cardiac injury evidenced by a decreased histopathologic score, cardiac-related enzymes, and cardiac function through the reduction of ROS production and cell apoptosis. This protective role was further confirmed by a simulation experiment in vitro. Moreover, we found that SAP-induced activation in MAPK signaling molecules in cardiomyocytes was significantly attenuated by Nox inhibition. Our data provide the first evidence that Nox hyperactivation acts as the main source of ROS production in the myocardium, increases oxidative stress, and promotes cell apoptosis via activating the MAPK pathway, which ultimately results in cardiac injury in SAP.

Abdominal paracentesis drainage ameliorates severe acute pancreatitis in rats by regulating the polarization of peritoneal macrophages.

AIM: To investigate the role of peritoneal macrophage (PM) polarization in the therapeutic effect of abdominal paracentesis drainage (APD) on severe acute pancreatitis (SAP). METHODS: SAP was induced by 5% Na-taurocholate retrograde injection in Sprague-Dawley rats. APD was performed by inserting a drainage tube with a vacuum ball into the lower right abdomen of the rats immediately after the induction of SAP. To verify the effect of APD on macrophages, PMs were isolated and cultured in an environment, with the peritoneal inflammatory environment simulated by the addition of peritoneal lavage in complete RPMI 1640 medium. Hematoxylin and eosin staining was performed. The levels of pancreatitis biomarkers amylase and lipase as well as the levels of inflammatory mediators in the blood and peritoneal lavage were determined. The polarization phenotypes of the PMs were identified by detecting the marker expression of M1/M2 macrophages via flow cytometry, qPCR and immunohistochemical staining. The protein expression in macrophages that had infiltrated the pancreas was determined by Western blot. RESULTS: APD treatment significantly reduced the histopathological scores and levels of amylase, lipase, tumor necrosis factor-α and interleukin (IL)-1ß, indicating that APD ameliorates the severity of SAP. Importantly, we found that APD treatment polarized PMs towards the M2 phenotype, as evidenced by the reduced number of M1 macrophages and the reduced levels of pro-inflammatory mediators, such as IL-1ß and L-selectin, as well as the increased number of M2 macrophages and increased levels of anti-inflammatory mediators, such as IL-4 and IL-10. Furthermore, in an in vitro study wherein peritoneal lavage from the APD group was added to the cultured PMs to simulate the peritoneal inflammatory environment, PMs also exhibited a dominant M2 phenotype, resulting in a significantly lower level of inflammation. Finally, APD treatment increased the proportion of M2 macrophages and upregulated the expression of the anti-inflammatory protein Arg-1 in the pancreas of SAP model rats. CONCLUSION: These findings suggest that APD treatment exerts anti-inflammatory effects by regulating the M2 polarization of PMs, providing novel insights into the mechanism underlying its therapeutic effect.

Association of polymorphisms in the vascular endothelial growth factor gene and its serum levels with diabetic retinopathy in Chinese patients with type 2 diabetes: a cross-sectional study.

BACKGROUND: Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis, and plays a key role in the pathogenesis of diabetic retinopathy (DR). This study was designed to identify the possible role of VEGF gene polymorphisms in the development of DR in type 2 diabetic patients in Chinese and clarify the relationship between VEGF serum levels and the risk of DR. METHODS: This cross-sectional study included 1 040 Chinese subjects with type 2 diabetes mellitus. There were 372 patients diagnosed with DR in the case group and 668 patients without DR in the control group. DNA from each patient was analyzed for VEGF polymorphisms of -2578A/C (rs699947), -1154G/A (rs1570360), -460C/T (rs833061), +405C/G (rs2010963), and +936C/T (rs3025039) using MassARRAY compact analyzer. The VEGF serum levels were quantified by enzyme-linked immunosorbent assay (ELISA). RESULTS: No evidence of association was observed between -2578 A/C (rs699947), +405C/G (rs2010963), +936C/T (rs3025039), and DR risk under stringent Bonferroni's correction. However, VEGF serum levels were significantly higher in DR patients than those of control group. The genetic variation of VEGF polymorphisms influenced VEGF serum levels; subjects carrying the VEGF -2578 C/C (rs699947) genotype had greater VEGF serum levels than those carrying the C/A genotype and VEGF serum levels were significantly higher in CC genotype of the +405C/G (rs2010963) compared with those of the other genotypes. CONCLUSIONS: The data did not suggest significant association between the VEGF polymorphisms and DR risk under stringent Bonferroni's correction. However, our study indicated that DR patients have higher VEGF levels than diabetic patients without retinopathy, and -2578A/C (rs699947) and +405C/G (rs2010963) may be important factors in determining serum VEGF levels.

Association between adiponectin concentrations and diabetic retinopathy in patients with type 2 diabetes: a meta analysis.

BACKGROUND: Numerous studies have investigated the association between adiponectin concentrations and diabetic retinopathy (DR) caused by type 2 diabetic mellitus. However, the results remain conflicting. We performed a meta-analysis to explore the relationship between adiponectin concentrations and risk of DR caused by type 2 diabetic mellitus from published articles. METHODS: A published literature search was performed through the PubMed, Cochrane Library, EMBASE, Science Citation Index Expanded database, Chinese CNKI, and Chinese Wan Fang databases for articles published in English and Chinese. Pooled standardized mean differences (SMDs) and 95% confidence intervals (95% CIs) were calculated using random or fixed effects model. Heterogeneity between studies was assessed using the Cochrane Q test and I(2) statistics. RESULTS: Nineteen studies with a total of 1 545 cases and 1 502 controls were retrieved. The original meta-analysis found a significant difference in the adiponectin concentrations between the DR and non-DR (NDR) groups. After excluding the high heterogeneity studies, the second meta-analysis also demonstrated the significant association (SMD (95% CI) = -0.62 (-0.80 to -0.44), P = 0.0001). According to the available data, there was statistical significance in the adiponectin concentrations considering non-proliferative DR (NPDR) versus NDR, PDR versus NPDR in Chinese populations with high heterogeneity. CONCLUSION: Adiponectin concentrations are correlated with DR; however, the relationship between adiponectin concentrations and DR needs more in-depth investigations with larger sample sizes.

Surface characteristics and cell adhesion: a comparative study of four commercial dental implants.

PURPOSE: The aims of this study were to compare surface properties of four commercial dental implants and to compare those implant systems' cell adhesion, which may be affected by the surface properties, and to provide scientific information on the selection of implants for clinicians. MATERIALS AND METHODS: The surface properties of four commonly used dental implants (3i Nanotite™, Astra OsseoSpeed™, Nobel Biocare TiUnite®, and Straumann SLActive®) were studied using MicroSpy profiler, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, and Raman microspectroscopy. Primary mouse alveolar bone cells were cultured on the surface of implants from the four companies. After 48-hour culture, SEM in combination with a quantitative analysis of SEM images was used to examine the cell adhesion. Cell adhesion rates (ratios of cell surface to implant surface) among different systems were compared. RESULTS: Distinct differences were found among these implants. Comparisons of roughness among three locations: flank, top, and valley within the same implant system, or in the same location among different implants were made. Generally Astra and Straumann systems showed the roughest surface, whereas 3i showed the smoothest surface. Multiple cracks were found on the surface of the Nobel Biocare system, which also had a dramatically lower level of titanium. In addition, rutile phase of titanium oxide was found in 3i, Astra, and Straumann systems, and anatase phase of titanium oxide was only detected in the Nobel Biocare system. After 48-hour culture, Astra and Straumann systems displayed the highest cell adhesion at the areas of flank, top, and valley of the implant surface. Primary cells also reached confluence on the valley, but significantly less in the 3i system. Nobel Biocare showed the least cell adhesion on the flank and valley. CONCLUSION: Implant systems have distinct differences in surface properties, leading to different cell adhesion results. Further in vivo study is needed to study the impact of the surface characteristics and different cell adhesion on the osseointegration between implant and bone.

Conversion of a partial removable dental prosthesis from Kennedy class II to class III using a dental implant and semiprecision attachments.

This article presents a design to convert a partial removable dental prosthesis (PRDP) from Kennedy class II to class III using a dental implant. Incorporating semiprecision attachments, this design provides desired esthetics, phonetics, and function.

Periodontal status of patients with hypophosphatemic rickets: a case series.

BACKGROUND: It was previously reported that dentin matrix protein 1-null mice, which are the hypophosphatemic rickets animal model, postnatally developed severe periodontal defects. However, to the best of our knowledge, it was not documented whether similar periodontal defects were present in human patients with hypophosphatemic rickets. The aim of this study is to evaluate the periodontal status of adult patients with hypophosphatemic rickets. METHODS: This case-series study evaluates the periodontal condition of adults with genetic hypophosphatemic rickets and compared their periodontal status with similar data from several cycles of the National Health and Nutrition Examination Survey (NHANES). Information regarding medical histories, dental histories, intraoral photos, probing depths (PD), calculated clinical attachment loss (AL), the presence of gingival recession, bleeding on probing, and full-mouth radiographic surveys were acquired. Descriptive statistics were used for comparison to NHANES data. RESULTS: A total of 10 adult patients with hypophosphatemic rickets (two males and eight females) were evaluated. The definition of periodontitis used in this study is as follows: "A periodontitis case was defined as a person who had ≥ 3 sites with clinical AL ≥ 4 mm and ≥ 2 sites with PD ≥ 3 mm." According to this definition, the patients exhibited periodontal bone loss at a much higher prevalence (60%) compared to the reported national periodontitis prevalence (3.6% to 7.3%). CONCLUSION: The preliminary data from our study suggests that patients with hypophosphatemic rickets are more prone to periodontal bone loss than the general population and may require a more careful examination by dental care providers.

The effect of metal recasting on porcelain-metal bonding: a force-to-failure study.

STATEMENT OF PROBLEM: Noble dental alloys are commonly remelted in the dental laboratory, but the effect of repeated casting on porcelain bond strength requires further documentation. PURPOSE: The purpose of this study was to determine if casting up to 3 times affected metal ceramic bond strength for 3 noble alloys using methodology in ANSI/ADA Specification No. 38. MATERIAL AND METHODS: Representative high-gold (Brite Gold XH), gold-palladium (W-5), and palladium-silver (IPS d.SIGN 53) alloys were cast into metal strips (25 x 3 x 0.5 mm), using torch melting. IPS InLine porcelain with overall dimensions of 8 x 3 x 1.1 mm was centrally applied on each strip. Metal ceramic specimens were also prepared after each alloy was melted a second and third time. There were 12 specimens in each of the 9 groups. Force to failure and porcelain bond compatibility index (tau(b)) were determined for each specimen, and statistical comparisons were made using the Ryan-Einot-Gabriel-Welsch multiple range test (experimental alpha=.05). Fractured specimens were examined with a scanning electron microscope. RESULTS: Mean values of tau(b) for specimen groups ranged from 40.6 to 48.2 MPa, and there were no significant differences among the 3 alloys after the first casting. For the high-gold alloy, tau(b) was significantly different for the first and third castings. Increases in size and frequency of interfacial voids were observed with the SEM when all alloys were cast 2 additional times. CONCLUSIONS: All 3 alloys had adequate porcelain bond strength (>25 MPa). The bond strength for the high-gold alloy was significantly greater for the third casting than for the first casting.