High Glucose Solution Research Articles

Donepezil is emerging as a potential therapeutic treatment in improving endothelial barrier function to prevent and treat coronary artery disease in Diabetes Mellitus.

Abstract Current treatments have shown limited success in reversing DM induced vascular endothelial barrier dysfunction. Vascular endothelium forms the inner most lining of the blood vessels, regulates variety of biological processes such as angiogenesis, wound healing and host defense mechanisms. During inflammatory conditions, such as diabetes mellitus and myocardial infarction endothelial cell-cell junctions start to disrupt because of the internalization of the junctional proteins, such as vascular endothelial (VE) cadherin. This leads to the formation of minute inter-endothelial gaps, and the infiltration of protein-rich fluid and immune cells in the interstitial space. If remains unchecked, the persistent buildup of edema underlying the endothelial lining sets the stage for the serious life-threatening complications. Therefore, we hypothesized that the donepezil prevents high glucose-induced endothelial barrier dysfunction by preventing the destabilization of junctional proteins. We investigated the potential protective role of Donepezil in high glucose induced increase in human coronary artery endothelial (HCAE) permeability and wound healing process. Wound healing assay was performed by employing electric signals to both wound and monitor the healing process in endothelial monolayer. To investigate the signaling mechanism involved in the protection offered by Donepezil, we found that Donepezil prevented loss of VE-cadherin in endothelial junctions, and abrogated stress fiber formation in endothelial cell exposed to high-glucose solution. In conclusion, our study shows that Donepezil maintained endothelial barrier function and improved wound healing process in endothelial cells exposed to high glucose. Chicago State University CTRE grant to Professor Nadeem Fazal, MD, PhD

Zhilong Huoxue Tongyu Capsule attenuates hemorrhagic transformation through the let-7f/TLR4 signaling pathway

Ethnopharmacological relevanceHemorrhagic transformation after acute ischemic stroke is a life-threatening disease that currently has no effective chemotherapy. Zhilong Huoxue Tongyu Capsule (ZL) is an empirical prescription of traditional Chinese medicine that is used to prevent and treat cardiovascular and cerebrovascular diseases in China. However, only a few studies have addressed the mechanisms of ZL in treating hemorrhagic transformation. Aim of the studyTo evaluate the anti-inflammatory effects of ZL on hemorrhagic transformation model rats and lipopolysaccharide (LPS)-induced RAW264.7 macrophages and to explore the underlying molecular mechanisms. Materials and methodsMurine RAW264.7 cells were treated with ZL and LPS (1 μg/mL), and cell viability was detected by cell counting kit-8 assay. RT-qPCR was used to detect the expression of inflammatory chemokines, microRNA let-7a/e/i/f, toll like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and nuclear factor kappa-B (NF-κB) p65. The protein expression levels of TLR4, MyD88, NF-κB p65, and apoptosis related molecules were determined by Western blotting. The apoptosis rate of RAW264.7 macrophages was detected by Annexin V-FITC/PI double staining. A hemorrhagic transformation model in rats was established by intraperitoneal injection of high glucose solution combined with thread embolization. Then, the model rats were observed behaviourally, pathologically, and molecularly. The gene expression of TLR4, MyD88, and NF-κB p65 was measured by RT-qPCR and used to evaluate the protective effect of ZL against hemorrhagic transformation in rats. ResultsZL (5, 20, 40 μg/mL) was beneficial in cell proliferation. LPS (1 μg/mL) stimulated the production of inflammatory chemokines and inhibited the production of let-7a/e/i/f, with let-7f being influenced most strongly. Moreover, overexpression of let-7f decreased the gene and protein levels of TLR4, MyD88, and NF-κB p65, downregulated TLR4, and inhibited its transcriptional activity. ZL (5, 20, and 40 μg·mL-1) inhibited the production of TLR4, MyD88, and NF-κB p65 and promoted the production of let-7f in a concentration-dependent manner. Furthermore, the blockade of TLR4 antagonized the promoting effects of TLR4 pathway activation in cell inflammation and apoptosis by downregulating let-7f. Critically, it was confirmed in vivo and in vitro that ZL upregulated the expression of let-7f and inhibited the gene expression of TLR4, MyD88, and NF-κB p65 to reduce inflammatory cell infiltration, which determined the occurrence of hemorrhagic transformation. ConclusionsZL can reduce inflammatory response by upregulating let-7f and subsequently inhibiting the TLR4 signaling pathway, thereby decreasing the occurrence of hemorrhagic transformation.

Developing an In Vitro Platform to Mimic the Pancreas‐Liver Endocrine Axis

Insulin is secreted from pancreatic islets in a pulsatile manner due to alternating periods of cellular activity and rest. The resulting pulses of insulin are critical for proper hormonal signaling and blood glucose regulation by the liver. To recreate the interaction between the endocrine pancreas and the liver using primary murine tissue, we have designed 3D printed microfluidic platforms that hold hepatocytes downstream of islets. Islets no longer oscillate in sync once isolated from the pancreas, so the cumulative insulin released is non‐pulsatile as demonstrated by taking the average intracellular calcium levels of multiple islets (Figure A, top). To force islets to secrete synchronized insulin pulses in vitro, we use programable syringe pumps that flow alternating high (11mM) and low (3mM) glucose solutions over isolated mouse islets. The syringe pump system aligns the oscillations which results in synchronized insulin release (Figure A, bottom). Next, we exposed primary murine hepatocytes to either 100nM pulses of insulin in three‐minute periods or constant 50nM insulin in a microfluidic system (Figure B). Both groups were exposed to the same amount of insulin, just in a different pattern. Hepatocytes treated with pulsatile insulin for 4 hours contained significantly more glycogen compared to those treated with continuous 50nM insulin (P<0.05, N=4). Future experiments will add hepatocytes downstream of the islets on the same platform to investigate the effect of pulsatile insulin and glucagon secretion on liver function. Exploring the interaction between pancreatic islets and hepatocytes will lead to a deeper understanding of the loss of pulsatile hormone secretion during the progression of type 2 diabetes.

Intrauterine hyperglycemia impairs endometrial receptivity via up-regulating SGK1 in diabetes.

Diabetes is a complex metabolic disorder which can adversely affect reproductive function. SGK1 is found to be up-regulated in multiple tissues of diabetic patients. However, the effects of diabetes on endometrial SGK1 expression and endometrial receptivity remain unknown. In this study, we established a streptozotocin-induced diabetic mouse model and observed reduced implantation sites, retarded development of pinopodes, increased SGK1, and aberrant expression of LIF and MUC1 in the endometrial epithelium. We injected the uterine lumen of normal mice with high-glucose solution and cultured endometrial cells in high-glucose medium to mimic intrauterine hyperglycemia. Both studies provided compelling evidence that hyperglycemia could lead to diminished embryo implantation and dysregulated SGK1, LIF and MUC1. Additionally, through over-expression of SGK1 in vivo and in vitro, we found that enhanced SGK1 also decreased LIF expression, increased MUC1 expression, and attenuated embryo implantation rate. We further identified that hyperglycemia-activated SMAD2/3 might be responsible for the enhancement of SGK1 and verified directly the interaction between SMAD3 and corresponding SMAD binding elements within SGK1 promoter. Taken together, our study confirmed the association between diabetes-related hyperglycemia and endometrial receptivity defects. Hyperglycemia-induced SGK1 has a tremendous role in this pathological process, rendering it as an attractive therapeutic target for diabetes-related reproductive disorders.

Proteolytic activation of Growth-blocking peptides triggers calcium responses through the GPCR Mthl10 during epithelial wound detection.

The presence of a wound triggers surrounding cells to initiate repair mechanisms, but it is not clear how cells initially detect wounds. In epithelial cells, the earliest known wound response, occurring within seconds, is a dramatic increase in cytosolic calcium. Here, we show that wounds in the Drosophila notum trigger cytoplasmic calcium increase by activating extracellular cytokines, Growth-blocking peptides (Gbps), which initiate signaling in surrounding epithelial cells through the G-protein-coupled receptor Methuselah-like 10 (Mthl10). Latent Gbps are present in unwounded tissue and are activated by proteolytic cleavage. Using wing discs, we show that multiple protease families can activate Gbps, suggesting that they act as a generalized protease-detector system. We present experimental and computational evidence that proteases released during wound-induced cell damage and lysis serve as the instructive signal: these proteases liberate Gbp ligands, which bind to Mthl10 receptors on surrounding epithelial cells, and activate downstream release of calcium.

High solid loading enzymatic hydrolysis of acetic acid-peroxide/acetic acid pretreated poplar and cellulase recycling

High solid loading saccharification is the premise of preparing high-concentration sugar which is beneficial to bioethanol production, but the limited sugar concentration and high enzyme dosage are two challenges. In this work, the glucan-rich acetic acid-hydrogen peroxide/acetic acid (AC-HPAC)-pretreated poplar (85.8%) were prepared for enzymatic hydrolysis at 10%-40% solid loading and the strategies for reducing cellulase dosage were explored. Results showed that the maximum glucose concentration reached to 250.8 g/L at 40% solid loading, which was the highest concentration in previous literatures. As the solid loading was 20%, the addition of Tween 80 saved 50% of cellulase and the recycling of unhydrolyzed residue (0.2 g/g DM) saved another 25% of cellulase, resulting in 152.2 g/L of glucose concentration with yield of 79.9%. This work showed potential of poplar to produce the high concentration glucose solution with low enzyme loading through the recycling of enzyme bound onto unhydrolyzed residue.

Exposition to glucose-based peritoneal dialysis fluids exacerbates adipocyte lipolysis and glycogen storage in rat adipose cells.

Glucose absorption during peritoneal dialysis (PD) is suspected to promote visceral fat accretion and weight gain in PD patients. The current study was designed to test the impact of glucose-based PD fluids on adipose cell lipolysis and glycogen content. Rat adipose cells, isolated from epididymal fat pad, were exposed to a 30 vol./70 vol. mixture of glucose-based dialysis solutions (containing 1.36% and 3.86% glucose, Physioneal 35®; Baxter) or Krebs-Henseleit buffer for 4 h. Adipose cells were further incubated with laboratory-made solutions containing 1.36% and 3.86% glucose or mannitol as an osmotic control. Baseline and noradrenaline-stimulated lipolysis was measured, and glycogen content assayed. The glucose-based commercial PD fluids as well as the laboratory-manufactured high glucose solutions exacerbated lipolysis in baseline and noradrenaline conditions and increased glycogen stores in adipose cells. Mannitol solutions (1.36% and 3.86%) used as an osmotic control did not produce such effects. This study provides the first evidence that glucose-based dialysis solutions increase basal as well as stimulated lipolysis in adipocytes, an effect that is directly attributable to high concentrations of glucose per se.

The Effect of an Atherogenic Diet and Acute Hyperglycaemia on Endothelial Function in Rabbits Is Artery Specific.

Hyperglycaemia has a toxic effect on blood vessels and promotes coronary artery disease. It is unclear whether the dysfunction caused by hyperglycaemia is blood vessel specific and whether the dysfunction is exacerbated following an atherogenic diet. Abdominal aorta, iliac, and mesenteric arteries were dissected from New Zealand White rabbits following either a 4-week normal or atherogenic diet (n = 6–12 per group). The arteries were incubated ex vivo in control or high glucose solution (20 mM or 40 mM) for 2 h. Isometric tension myography was used to determine endothelial-dependent vasodilation. The atherogenic diet reduced relaxation as measured by area under the curve (AUC) by 25% (p < 0.05), 17% (p = 0.06) and 40% (p = 0.07) in the aorta, iliac, and mesenteric arteries, respectively. In the aorta from the atherogenic diet fed rabbits, the 20 mM glucose altered EC50 (p < 0.05). Incubation of the iliac artery from atherogenic diet fed rabbits in 40 mM glucose altered EC50 (p < 0.05). No dysfunction occurred in the mesentery with high glucose incubation following either the normal or atherogenic diet. High glucose induced endothelial dysfunction appears to be blood vessel specific and the aorta may be the optimal artery to study potential therapeutic treatments of hyperglycaemia induced endothelial dysfunction.

P1131STEADY CONCENTRATION PERITONEAL DIALYSIS INCREASES ULTRAFILTRATION AND SODIUM REMOVAL COMPARED TO CAPD

Abstract Background and Aims Fluid and sodium removal may be a challenge during glucose-based PD, leading to increased use of high glucose solutions to maintain sufficient fluid removal. This may in turn lead to increased sodium sieving, resulting in a decreased sodium removal. Carry Life® UF uses Steady Concentration PD (SCPD), where the infusion of glucose compensates for glucose uptake and maintains the intraperitoneal glucose concentration at a sufficient level providing a continuous ultrafiltration throughout the dwell. The present study investigated the effect of Carry Life UF compared to a standard CAPD dwell regarding ultrafiltration, sodium removal and glucose absorption. Method Eight stable PD patients were included in the study. Subjects were treated with 5-hour Carry Life UF treatments using three different glucose doses (11, 14, 20 g/h). An initial fill with 1500 ml, 13.6 g/l glucose PD solution was used. A small volume of dialysate was drained hourly to avoid overfill. A standard 4-hour Peritoneal Equilibration Test (PET) (2000 ml, 22.7 g/l glucose) was used as control. Data expressed as mean ± SD, statistical analysis using one-way ANOVA. Results Ultrafiltration was significantly increased during the Carry Life UF treatments compared to PET (646±256, 739±312, 863±380 ml for 11 g/h, 14 g/h and 20 g/h, respectively, vs. 162±242 ml for PET, p&amp;lt;0.01). Sodium removal increased significantly during Carry Life UF treatments (86±27, 92±33, 110±37 mmol/dwell for 11, 14, and 20 g glucose/h) compared to PET (22±33 mmol/dwell, p&amp;lt;0.001). Figure a shows that the intraperitoneal glucose concentration increased during the first hours of the Carry Life UF treatments and remained stable during the remainder of the treatments. During PET the glucose concentration decreased gradually during the treatment. The maximum intraperitoneal glucose concentration did not exceed 26 g/l (144 mmol/l) during the Carry Life UF treatments. The UF volume per gram of glucose uptake was significantly higher for the two lower Carry Life UF glucose doses compared to PET (Figure b). Conclusion SCPD performed with Carry Life® UF maintained a stable intraperitoneal glucose concentration during the 5-hour treatment which generated significantly higher UF volumes compared to 4-hour PET. During the Carry Life UF treatments glucose was used more efficiently, particularly for the two lowest doses, in comparison to PET. The increased sodium removal with Carry Life® UF enables a better balance between UF volume and sodium removal than for example during APD. In summary, SCPD using Carry Life® UF increases the efficiency of PD compared to standard, glucose-based CAPD with respect to ultrafiltration and sodium removal.

Compact fluidic system for functional assessment of pancreatic islets.

Transplantation of pancreatic islets is becoming a promising therapy for people with type I diabetes. In this study, we present a compact fluidic system that enables assessment of islet functionality ex vivo for efficient islet transplantation. The fluidic system includes a micromesh sheet-embedded chip. Islets can be loaded easily on the micromesh sheet and observed clearly by microscopy. Islets on the mesh sheet mainly remained in place during perfusion and did not get damaged by hydraulic pressure because of high porosity of the micromesh sheet. The fluidic system was assembled with a sample fraction chip of polydimethylsiloxane. The chip includes a channel and columns, both having surfaces that were super-hydrophilized so that solutions could flow smoothly within the chip by gravity. Using mouse pancreatic islets, a dynamic glucose-stimulated insulin secretion test was performed to examine the performance of the fluidic system. The system successfully analyzed levels and patterns of insulin secretion upon exposure of the islets to low- and high-glucose solutions in turns, thus demonstrating its capacity to assess islet functions more easily and cost-effectively.

Targeted Derivation of Organotypic Glucose- and GLP-1-Responsive β Cells Prior to Transplantation into Diabetic Recipients.

SummaryGeneration of functional β cells from pluripotent sources would accelerate diagnostic and therapeutic applications for diabetes research and therapy. However, it has been challenging to generate competent β cells with dynamic insulin-secretory capacity to glucose and incretin stimulations. We introduced transcription factors, critical for β-cell development and function, in differentiating human induced pluripotent stem cells (PSCs) and assessed the impact on the functionality of derived β-cell (psBC) progeny. A perifusion system revealed stepwise transduction of the PDX1, NEUROG3, and MAFA triad (PNM) enabled in vitro generation of psBCs with glucose and GLP-1 responsiveness within 3 weeks. PNM transduction upregulated genes associated with glucose sensing, insulin secretion, and β-cell maturation. In recipient diabetic mice, PNM-transduced psBCs showed glucose-responsive insulin secretion as early as 1 week post transplantation. Thus, enhanced pre-emptive β-cell specification of PSCs by PNM drives generation of glucose- and incretin-responsive psBCs in vitro, offering a competent tissue-primed biotherapy.

Neovascularization and functional assessment of human pancreatic islets encapsulated with immuno‐modulatory stem cells

Background &amp; ObjectiveDeveloping successful therapies based on re‐introduction of healthy pancreatic islets in diabetic patients requires new strategies to combat the immune response caused by implantation, as well as improving neovascularization and engraftment of the implant. Human amniotic epithelial cells (AECs) are immuno‐modulatory stem cells that can confer a local immune‐privileged environment in vivo, and block grafted tissue rejection [1]. The objective of this study was to develop a protocol for encapsulating islets with AECs, and examine the effects of encapsulation on islet function, and neovascularization.MethodsHuman pancreatic islets were individually placed in ultra‐low attachment round bottom wells with human islet medium, and were divided into three experimental groups: 1) islet‐only, 2) adipose‐derived stem cells (ASCs)+islet, and 3) AECs+islet. For groups 2 and 3, each islet was assumed to have ~2000 beta cells, and the stem cells were added to each well to encapsulate individual islets at 2:1 cell ratio. The temporal c‐peptide secretion level was measured after 3 and 6 days by perfusing the islets with basal and high glucose solutions using dynamic readout assay, and confirmed the functionality of the encapsulated islets. To assess the angiogenic properties of encapsulation, cell culture supernates were collected after 6 days of culture, and used for an angiogenesis array kit, to identify and compare the level of 52 angiogenic factors present in each group. The same test was repeated for ASC‐ and AEC‐only cultures to identify any effects caused by the cell encapsulation.Results &amp; ConclusionsThe level of pro‐angiogenic factors increased in encapsulated groups compared to the islet‐only group (Fig. 1). A larger increase in angiogenic factors in encapsulated islets compared to stem cell‐only groups demonstrated a synergetic angiogenic effect caused by encapsulation of islets with ASCs and AECs. To test the angiogenic response in a physiological scenario, the islets were seeded on rat mesentery tissues, and cultured for 6 days, and the level of angiogenic response was compared between different groups. Our results highlight the effect of encapsulating human islets with ASCs and AECs on engraftment and neovascularization, and showcase the potential of the islet cell encapsulation method for a successful long‐term implantation in patients with diabetes.Support or Funding InformationThe Virginia Catalyst and UVA Center for Advanced BiomanufacturingThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Hyperglycemia induces mechanical hyperalgesia and depolarization of the resting membrane potential of primary nociceptive neurons: Role of ATP-sensitive potassium channels

Cumulating data suggests that ion channel alterations in nociceptive neurons might be involved in the development of diabetic painful neuropathy. In the present study we investigated the involvement of ATP-sensitive potassium (K+ATP) channels in the acute effect of high glucose solution in vitro and in vivo. High glucose concentrations depolarized cultured nociceptive neurons and depolarization was blocked by the K+ATP opener, diazoxide or by insulin. Glucose injection at the rat dorsal root ganglia (L5) resulted in acute mechanical hyperalgesia that was blocked by diazoxide. Mannitol injection indicates that osmolarity changes are not responsible for glucose effect. Therefore, this study suggests that K+ATP channels expressed in peripheral sensory neurons might be involved in the development of diabetic painful neuropathy. Since sulfonylureas, that act by blocking K+ATP are used for diabetes treatment, it is important to evaluate the possible side effects of such drugs at primary sensory neurons.

Molecular and functional characterization of sirt4 and sirt6 in Megalobrama amblycephala under high glucose metabolism

We analyzed the sequences of sirt4 and sirt6 and their changes in expression after oral glucose administration in blunt snout bream (Megalobrama amblycephala). We cloned sirt4 and sirt6 and found that their full-length cDNA sequences were 1530 bp and 1723 bp, respectively; their amino acid sequences were 93% and 92% identical to Danio rerio. Megalobrama amblycephala were fed a high glucose solution (3 g/kg). Normally, sirt4 expression is higher in spleen, intestine, and gill (P < .05), and sirt6 expression is higher in intestine and gill (P < .05). After oral glucose administration, sirt4 and sirt6 expression increased in liver and gill, and sirt4 expression increased in intestine at 0.5 h (P < .05). In contrast, sirt4 in kidney and sirt6 in head kidney were downregulated at 1 h (P < .05). Expression of sirt4 was upregulated in brain, head kidney, spleen, muscle, and liver 2 h, 4 h, 4 h/24 h, 8 h, and 24 h, respectively (P < .05). Expression of sirt4 was downregulated in kidney at 8 h-48 h (P < .05). Expression of sirt6 was upregulated in intestine, liver, muscle, kidney, and spleen at 4 h/24 h, 8 h/24 h, 12 h, 12 h, and 24 h, respectively (P < .05). We report that sirt4 and sirt6 are highly conserved in evolution and exhibit tissue-specific expression profiles. We demonstrate that the expression of sirt4 and sirt6 are tissue-specific, and depend upon tissue-specific responses to glucose metabolism.

The Interplay between Hyperresistinemia, Elevated ROS, and Hyperglycemia in Diabetic Rats and Their Roles in Diabetes‐Associated Neutrophil Dysfunction

Resistin originally was found as an adipocyte‐derived polypeptide leading to insulin resistanis. Emerging evidence suggests that it plays important roles in various inflammatory diseases. The levels of hyperresistinemia has been associated with immunosuppression and serves as biomarker for the severity of the diseases. Neutrophils play a key role in host defenses against invading microorganisms by releasing large quantities of Reactive Oxygen Species (ROS) via respiratory burst, which are essential for killing bacteria. Diabetic patients have an increased risk of infections mainly as a result of impaired neutrophil functions. Our recent study found that reduced Nrf2 (NF‐E2‐related factor 2), a master transcription factor regulating antioxidant defenses, contributes to elevated ROS levels and increased microvessel permeability in diabetic rats. Diabetes‐associated microvessel dysfunction is highly associated with inflammation. However, the inter‐relationship between the plasma resistin levels, elevated ROS, and their effect on neutrophil function under Diabetic conditions remains unclear and even contradictory. This study aims to examine the interplay between the plasma resistin levels, increased oxidant stress caused by downregulation of Nrf2‐dependent antioxidant defenses, and the neutrophils function in Diabetic rats. Plasma resistin concentrations were determined with a sandwich enzyme immunoassay kit from Wide‐type (WT) Rat, Nrf2 Knock out (Nrf2−/−) out rats and streptozotocin (STZ)‐induced Nrf2−/− diabetic rat. Diabetic rat had experienced elevated blood glucose and A1C level at 404 ± 10 mg/dl and 10.20% ± 0.14% for 14–21 days before the experiments. Neutrophils were isolated from normal and diabetic rats and neutrophil released ROS upon formyl‐Met‐Leu‐OH (fMLP) stimulation was quantified by measuring chemiluminescence (CL). The resistin concentration in WT rats was 6.16 ± 0.97 ng/ml. Nrf2−/− rats significantly increases the resistin level to 15.88 ± 0.45 ng/ml. The resistin levels in diabetic Nrf2−/− rats was markedly increased to 31.67 ± 2.62 ng/ml. Meanwhile, we found neutrophil killing power was significantly reduced in diabetic rats. The peak CL of diabetic neutrophils upon fMLP stimulation was reduced from 826 ± 202 RLU (normal neutrophils) to 259 ± 51 RLU. The CL area under curve, a measure of total ROS production, in normal and diabetic neutrophils was 77614 ± 5509 and 43327 ± 3561 RLU, respectively. When the normal neutrophils were incubated with high glucose solution, a reduced fMLP‐stimulated CL response was also observed, but that couldn't match the reduction of the ROS production in Diabetic rats. These results indicate that increased plasma ROS levels may play a role in increased resistin levels. Further, both increased ROS, hyperresistinemia and hyperglycemia may synergistically contribute to neutrophil dysfunction in diabetes.Support or Funding InformationSupported by HL130363 and DK097391This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Pleural Coating by 50% Glucose Solution Reduces Postoperative Recurrence of Spontaneous Pneumothorax

Video-assisted thoracoscopic surgery is the standard procedure for treatment of spontaneous pneumothorax. However, postoperative recurrence is relatively common even if an absorbable covering sheet is used for reinforcement of the visceral pleura. Injection of a high concentration glucose solution to the thoracic cavity was recently reported to be effective in stopping postoperative air leakage or as a prophylactic procedure to prevent postoperative recurrence of spontaneous pneumothorax. Therefore, we used 50 mL of a 50% glucose solution for pleural coating (GPC) on an absorbable sheet intraoperatively to prevent postoperative recurrence of spontaneous pneumothorax. This is a retrospective study, and patient backgrounds are heterogeneous. We evaluated the feasibility of GPC using propensity scores to adjust for heterogeneity in their backgrounds. Between January 2010 and December 2017, 376 patients who underwent video-assisted thoracoscopic surgery, with or without GPC, were evaluated. The GPC group consisted of 106 patients, and the non-GPC group consisted of 270. We analyzed the factors preventing postoperative recurrence of spontaneous pneumothorax by univariate analysis and Cox regression analysis with or without propensity score matching. Univariate analysis revealed age of 25 or older, smoking habit, no history of an ipsilateral operation, and GPC were significant factors preventing postoperative recurrence. GPC significantly prevented postoperative recurrence as shown by Cox regression analysis with propensity score matching (hazard ratio, 0.15; p= 0.014) and the inverse-probability of treatment weighted method (hazard ratio, 0.23; p= 0.0038). Intraoperative GPC significantly reduced the postoperative recurrence rate of spontaneous pneumothorax.

High glucose induces the proliferation of prostatic cells via downregulating MRE11.

The aim of the present study was to investigate the candidate genes and pathways associated with benign prostatic hyperplasia (BPH) and diabetes. In vitro experiments were performed using normal prostatic epithelial RWPE-1 and HPr-1 cells. The cell lines were treated with a high-glucose solution and MTS and bromodeoxyuridine assays were used to assess cell viability. Transcriptome sequencing was used to screen the candidate genes. The expression of candidate genes was further verified by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting. A meiotic recombination 11 (MRE11) overexpression vector was designed and transfected into RWPE-1 cells to verify the function of MRE11. A streptozotocin-induced diabetic rat model was established and rat MRE11 levels were determined by RT-qPCR and immunohistochemical staining. High concentrations of glucose resulted in RWPE-1 and HPr-1 cells with high viability. Transcriptome sequencing revealed that MRE11 was downregulated when RWPE-1 cells were exposed to high-glucose conditions. When MRE11 was overexpressed, cell viability decreased and cell apoptosis was induced under high-glucose conditions. Prostatic tissues from rats were collected and assessed; MRE11 expression was observed to be decreased, which was consistent with the in vitro cell experiments. BPH may be associated with diabetes, as MRE11 expression in prostatic cells was decreased when exposed to high-glucose conditions. Therefore, MRE11 may have potential as a biomarker for the early diagnosis of BPH and diabetes.

Human Peritoneal Mesothelial Cell Death Induced by High-Glucose Hypertonic Solution Involves Ca2+ and Na+ Ions and Oxidative Stress with the Participation of PKC/NOX2 and PI3K/Akt Pathways.

Chronic peritoneal dialysis (PD) therapy is equally efficient as hemodialysis while providing greater patient comfort and mobility. Therefore, PD is the treatment of choice for several types of renal patients. During PD, a high-glucose hyperosmotic (HGH) solution is administered into the peritoneal cavity to generate an osmotic gradient that promotes water and solutes transport from peritoneal blood to the dialysis solution. Unfortunately, PD has been associated with a loss of peritoneal viability and function through the generation of a severe inflammatory state that induces human peritoneal mesothelial cell (HPMC) death. Despite this deleterious effect, the precise molecular mechanism of HPMC death as induced by HGH solutions is far from being understood. Therefore, the aim of this study was to explore the pathways involved in HGH solution-induced HPMC death. HGH-induced HPMC death included influxes of intracellular Ca2+ and Na+. Furthermore, HGH-induced HPMC death was inhibited by antioxidant and reducing agents. In line with this, HPMC death was induced solely by increased oxidative stress. In addition to this, the cPKC/NOX2 and PI3K/Akt intracellular signaling pathways also participated in HGH-induced HPMC death. The participation of PI3K/Akt intracellular is in agreement with previously shown in rat PMC apoptosis. These findings contribute toward fully elucidating the underlying molecular mechanism mediating peritoneal mesothelial cell death induced by high-glucose solutions during peritoneal dialysis.

Encapsulating peritoneal sclerosis

Encapsulating peritoneal sclerosis (EPS) is a complication of peritoneal dialysis (PD) with a low prevalence but high mortality. It is characterized by peritoneal inflammation and fibrosis with subsequent development of intestinal encapsulation. It is associated with a long lapse on PD, frequent episodes of peritonitis, high glucose solution use, and high peritoneal transport status. To report the clinical features of patients on PD, who developed EPS. Review of medical records of 12 patients aged 43 ± 10 years (eight women) who developed EPS. The mean time spent on PD was 98 months. The main clinical manifestations were abdominal pain in 82% and ultrafiltration failure in 63%. In 92%, there was a history of peritonitis and 75% had high peritoneal transport at the time of diagnosis. The main findings in computed tomography were peritoneal calcification and thickening. There was a biopsy compatible with the diagnosis in 10 cases. Treatment consisted in withdrawal from PD, removal of PD catheter and the use of corticoids and tamoxifen. After withdrawal from PD 50% of patients became asymptomatic. The rest had intermittent abdominal pain and altered bowel movements. Two patients died (17%). EPS is a serious complication of PD, which should be suspected in any patient with compatible clinical symptoms, long time on PD, multiple episodes of peritonitis and high peritoneal transport profile.

Chemical communication between cardiac cells is disrupted by high glucose: Implications for the diabetic heart

The influence of high glucose solution on the chemical communication between cardiac cells was investigated in cell pairs isolated from the left ventricle of adult Wistar Kyoto rats. For this, Lucifer Yellow CH was dialyzed into one cell of the pair using the whole cell clamp technique, and the diffusion of dye in the dialyzed as well as in non-dialyzed cell, was followed by measuring the intensity of fluorescence in both cells as a function of time. The results indicated that: 1) high glucose solution (25mM) disrupted chemical communication between cardiac cells; 2) the effect of high glucose solution was reduced by Bis-1 (10−9M) which is a PKC inhibitor, and by enalapril (10−9M); 3) intracellular dialysis of Ang II (100nM) also caused dye uncoupling; 4) calculation of gap junction permeability (Pj) (cm/s) indicated a value of 3±0.07×10−5cm/s; n=32; (6 animals) for the controls and 0.4±0.86×10−6cm/s; n=35 (6 animals) (P<0.05) for cells incubated with high glucose solution for 24h; 5) measurements of Pj for cell pairs treated with hypertonic solution plus Bis-1 (10−9M) or enalapril maleate (10−9M) showed no significant change of Pj (P>0.05). Conclusions: high glucose (25mM) disrupts chemical communication between cardiac cells-an effect highly dependent on PKC activation. The possible role of enhanced intracellular Ang II levels induced by high glucose on the disruption of chemical communication was discussed as well as the possible implications of these findings for the diabetic heart.