Effects of intensive blood pressure control on left ventricular hypertrophy in aortic valve disease.

BACKGROUND: Hypertension adds to the pressure overload on the left ventricle (LV) in combination with aortic valve (AV) disease, but the optimal blood pressure (BP) targets for patients with AV disease remain unclear. We tried to investigate whether intensive BP control reduces LV hypertrophy in asymptomatic patients with aortic stenosis (AS) or aortic regurgitation (AR). METHODS: A total of 128 hypertensive patients with mild to moderate AS (n = 93) or AR (n = 35) were randomly assigned to intensive therapy, targeting a systolic BP <130 mm Hg, or standard therapy, targeting a systolic BP <140 mm Hg. The primary end point was the change in LV mass from baseline to the 24-month follow-up. Secondary end points included changes in severity of AV disease, LV volumes, ejection fraction and global longitudinal strain (GLS). RESULTS: The treatment groups were generally well balanced regarding the baseline characteristics. The mean (±SD) age of the patients was 68 ± 8 years and 48% were men. The mean BP was 145 ± 12/81 ± 10 mm Hg at baseline. Medication at baseline was similar between the 2 groups. The 2 treatment strategies resulted in a rapid and sustained difference in systolic BP (P < .05). At 24-month, the mean systolic BP was 129 ± 12 mm Hg in the intensive therapy group and 135 ± 14 mm Hg in the standard therapy group. No patient died or underwent AV surgery during follow-up in either of the groups. LV mass was changed from 189.5 ± 41.3 to 185.6 ± 41.5 g in the intensive therapy group (P = .19) and from 183.8 ± 38.3 to 194.0 ± 46.4 g in the standard therapy group (P < .01). The primary end point of change in LV mass was significantly different between the intensive therapy and the standard therapy group (-3.9 ± 20.2 g vs 10.3 ± 20.4 g; P = .0007). The increase in LV mass index was also significantly greater in the standard therapy group (P = .01). No significant differences in secondary end points (changes in severity of AV disease, LV volumes, ejection fraction and GLS) were observed between the treatment groups. CONCLUSIONS: Among hypertensive patients with AV disease, intensive hypertensive therapy resulted in a significant reduction in LV hypertrophy, although progression of AV disease was similar between the treatment groups. CLINICAL TRIAL REGISTRATION: http://ClinicalTrials.gov (Number NCT03666351).

Safety and efficacy of preauricular fistulectomy with fascia-anchoring suture technique: A large case series.

OBJECTIVE: This study aimed to analyze the safety and efficacy of preauricular fistulectomy with fascia-anchoring suture technique through large case series. In addition, differences in surgical outcomes according to preoperative status and age were investigated. METHODS: In this retrospective study, 380 patients (450 ears) with preauricular fistula (PAF) who underwent preauricular fistulectomy with fascia-anchoring suture technique by a single surgeon (E.P) were enrolled. Patients were divided into fresh, previous incision and drainage (I&D), and the revision surgery groups according to the preoperative status. Additionally, they were divided into adult and pediatric groups according to age. Patient's demographics, postoperative infections, and recurrence rates were analyzed. RESULTS: The mean age of the patients was 28.3 years, and there were 119 males and 261 females. Out of 450 PAFs (n = 281 in the fresh groups, n = 119 in the previous I&D groups, and n = 50 in the revision groups), 21 (4.7 %) cases had postoperative infections and 12 (2.7 %) cases had recurrence. There was no difference in postoperative infections, regardless of the preoperative condition (I&D group, p = 0.701; revision group, p = 0.658). The recurrence rate was higher in the revision group than in the fresh and I&D groups (p = 0.004). There was no significant difference in postoperative infection (p = 0.221) or recurrence (p = 0.161) between adults and children. CONCLUSIONS: The study found that performing preauricular fistulectomy with a fascia-anchoring suture technique led to low rates of postoperative infections and recurrences. These positive outcomes were consistent across different patient groups categorized by preoperative status and age, indicating the technique's safety and effectiveness for all patients with preauricular fistulas.

Regulation of T Helper Cell Type 2 Immune Response by Controlling Beta-2 Adrenergic Receptor in Dendritic Cells of Patients with Allergic Rhinitis.

INTRODUCTION: Allergic diseases are mediated by T helper cell type 2 (Th2) cells, which are differentiated by dendritic cells (DCs). Recently, it was reported that cAMP concentration in DCs is important for inducing allergic responses. However, the regulatory function of cAMP in DCs in Th2 immune responses is unclear. It was hypothesized that the regulation of G protein-coupled receptors (GPCRs) to increase cAMP levels in DCs would reduce Th2 immune responses. METHODS: Human DCs from patients with allergic rhinitis (AR) and from healthy controls were subjected to next-generation sequencing (NGS) to identify potential GPCR. To investigate the functions of GPCR agonists, the in vitro co-culture experiment that THP-1 cells were differentiated into DCs and cultured with human CD4+ T-cells and an AR animal in vivo model were used. RESULTS: Among the GPCRs, the beta-2 adrenergic receptor (ADRB2) of allergic DCs was significantly increased by NGS analysis. The expression of ADRB2 was also increased in Der p 1-treated DCs, which was reduced by treatment with the ADRB2 agonist salbutamol. Salbutamol treatment induced cAMP production in THP-1 derived DCs. In an in vitro co-culture experiment, salbutamol-treated DCs reduced the secretion of Th2 cytokine. In an in vivo AR animal experiment, salbutamol-administered mice showed reduced allergic behavior and Th2 cytokine expression in the nasal mucosa. CONCLUSIONS: The regulation of ADRB2 with salbutamol alleviated the allergic response in vitro DC-T cell co-culture and in vivo AR animal models, suggesting that ADRB2 is a therapeutic target for AR and that ADRB2 agonists may be a promising medication for AR.

Preventive effect of Helicobacter pylori eradication on the coronary heart diseases depending on age and sex with a median follow-up of 51 months.

BACKGROUND: The association between Helicobacter pylori (HP) infection and coronary heart disease (CHD) is controversial. This study aimed to investigate the effect of H. pylori eradication on CHD, especially in terms of age and sex. MATERIALS AND METHODS: From May 2003 to March 2022, 4765 subjects with H. pylori infection and without CHD (median follow-up: 51 months) were prospectively enrolled. The participants were categorized into two groups: H. pylori eradication and H. pylori non-eradication. After propensity-score matching (PSM), the effect of H. pylori eradication on CHD was analyzed using Cox proportional hazards. RESULTS: There were no significant differences in age, sex, alcohol consumption, smoking habits, history of diabetes, hypertension, and dyslipidemia, and aspirin intake between the eradication and non-eradication groups (3783 vs. 982) before and after PSM. Multivariate analysis after PSM showed that H. pylori eradication (HR: 0.489, CI: 0.314-0.761, p = .002), age (HR: 1.027, CI: 1.007-1.047, p = .007), hypertension (HR: 2.133, CI: 1.337-3.404, p = 001), dyslipidemia (HR: 1.758, CI: 1.086-2.848, p = .022), and aspirin intake (HR: 2.508, CI: 1.566-4.017, p < .001) were associated with CHD development. H. pylori eradication prevented CHD in males ≤65 years (HR: 0.133, CI: 0.039-0.455, p = .001), but not in those aged >65 years (p = .078) (p for interaction = .022). In contrast, females aged >65 years (HR: 0.260, CI: 0.110-0.615, p = .002) were protected by H. pylori eradication and not those ≤65 years (p = .485) (p for interaction = .003). This preventive effect increased more after PSM, particularly in males ≤65 years and females >65 years. CONCLUSIONS: H. pylori eradication prevented CHD and this effect was different depending on age and sex.

Raspberry Pi Platform Wireless Sensor Node for Low-Frequency Impedance Responses of PZT Interface.

A wireless impedance monitoring system, called SSeL-Pi, is designed to have cheap, mobile, and handy practical features as compared to wired commercial impedance analyzers. A Raspberry Pi platform impedance sensor node is designed to measure signals at a low-frequency range of up to 100 kHz. The low-frequency impedance measurement via the proposed node has been combined with a new PZT interface technique for measuring local responses sensitive to structural damage. The new PZT interface can work as a surface-mounted or embedded sensor, and its local dynamic characteristics are numerically analyzed to pre-determine an effective impedance resonant frequency range of less than 100 kHz. Next, a software scheme was designed to visualize the input/output parameters of the proposed SSeL-Pi system (i.e., Raspberry Pi platform and PZT interface) and automate signal acquisition procedures of the impedance sensor node. The calibration for impedance signals obtained from the proposed system was performed by a series of procedures, from acquiring real and imaginary impedance to adjusting them with respect to a commercial impedance analyzer (HIOKI-3532). The feasibility of the wireless impedance monitoring system was experimentally evaluated for PZT interfaces that were subjected to various compressive loadings. The consistent results analyzed from signals measured by the SSeL-Pi and HIOKI 3532 systems were observed. Additionally, the strong relationships between impedance features (frequency shift and RMSD index) and compressive stresses of the PZT interfaces showed the potential for axial force/stress variation monitoring in real structures using the Raspberry Pi platform impedance sensor node and developed PZT interface.

Screening Key Genes and Biological Pathways in Nasopharyngeal Carcinoma by Integrated Bioinformatics Analysis.

The purpose of this study was to identify the hub genes and biological pathways of nasopharyngeal carcinoma (NPC) through bioinformatics analysis and potential new therapeutic targets. In this study, three datasets were downloaded from the Gene Expression Omnibus (GEO), and differentially expressed genes (DEGs) between NPC and normal tissues were analyzed using the GEO2R online tool. Volcano and heat maps of the DEGs were visualized using the hiplot database. Gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the upregulated and downregulated DEGs were performed using the DAVID database. Finally, we established a protein-protein interaction (PPI) network using the STRING database and showed the differential expression of hub genes between the normal and tumor tissues. In all, 109,371,221 upregulated DEGs and 139,226,520 downregulated DEGs were obtained in datasets GSE40290, GSE61218, and GSE53819, respectively, and 18 common differential genes, named co-DEGs, were screened in the three datasets. The most abundant biological GO terms of the co-DEGs were inflammatory response et al. The KEGG pathway enrichment analysis showed that co-DEGs mainly participated in the interleukin (IL)-17 signaling pathway et al. Finally, we identified four hub genes using PPI analysis and observed that three of them were highly expressed in tumor tissues. In this study, the hub genes of NPC, such as PTGS2, and pathways such as IL-17 signaling, were identified through bioinformatics analysis, which may be potential new therapeutic targets for NPC.

Melatonin ameliorates SGLT2 inhibitor-induced diabetic ketoacidosis by inhibiting lipolysis and hepatic ketogenesis in type 2 diabetic mice.

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are effective hypoglycemic agents that can induce glycosuria. However, there are increasing concerns that they might induce diabetic ketoacidosis. This study investigated the effect of melatonin on SGTL2i-induced ketoacidosis in insulin-deficient type 2 diabetic (T2D) mice. The SGLT2i dapagliflozin reduced blood glucose level and plasma insulin concentrations in T2D mice, but induced increases in the concentrations of plasma ß-hydroxybutyrate, acetoacetate, and free fatty acid and a decrease in the concentration of plasma bicarbonate, resulting in ketoacidosis. Melatonin inhibited dapagliflozin-induced ketoacidosis without inducing any change in blood glucose level or plasma insulin concentration. In white adipose tissue, melatonin inhibited lipolysis and downregulated phosphorylation of PKA, HSL, and perilipin-1. In liver tissue, melatonin suppressed cellular cyclic AMP levels and downregulated phosphorylation of PKA, AMPK, and acetyl-CoA carboxylase (ACC). In addition, melatonin increased hepatic ACC activity, but decreased hepatic CPT1a activity and acetyl-CoA content. These effects of melatonin on lipolysis and hepatic ketogenesis were blocked by pretreatment with melatonin receptor antagonist or PKA activator. Collectively, these results suggest that melatonin can ameliorate SGLT2i-induced ketoacidosis by inhibiting lipolysis and hepatic ketogenesis though cyclic AMP/PKA signaling pathways in T2D mice. Thus, melatonin treatment may offer protection against SGLT2i-induced ketoacidosis.

Correction to: Sweet taste receptors as a tool for an amplifying pathway of glucose-stimulated insulin secretion in pancreatic ß cells.

The publisher would like to apologize for the failed cross-linking of the following Commentary by Jae-Hyung Park and Dae-Kyu Song.

Octanoic acid potentiates glucose-stimulated insulin secretion and expression of glucokinase through the olfactory receptor in pancreatic ß-cells.

Olfactory receptors (ORs) are G protein-coupled receptors that mediate olfactory chemosensation, leading to the perception of smell. ORs are expressed in many tissues, but their functions are largely unknown. Here, we show that the olfactory receptor Olfr15 is highly and selectively expressed in both mouse pancreatic ß-cells and MIN6 cells. In addition, octanoic acid (OA), a medium-chain fatty acid, potentiates glucose-stimulated insulin secretion (GSIS). The OA-induced enhancement of GSIS was inhibited by Olfr15 knockdown. Treatment with a PLC inhibitor or an Ins(1,4,5)P3 receptor (IP3R) antagonist also blocked the OA-induced enhancement of GSIS. These results suggest that OA potentiates GSIS via Olfr15 though the PLC-IP3 pathway. Furthermore, long-term treatment with OA increased cellular glucose uptake in MIN6 cells by up-regulating the expression of glucokinase (GK). Moreover, this process was blocked by an IP3R antagonist and a Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) inhibitor. Similarly, OA stimulated GK promoter activity, while either Olfr15 or CaMKIV knockdown blocked the stimulatory effect of OA on GK promoter activity. These results suggest that long-term treatment of OA induces GK promoter activity via Olfr15 through the IP3-CaMKK/CaMKIV pathway. In islets from type 2 diabetic mice, the expression level of Olfr15 and the OA-induced enhancement of GSIS were strongly reduced. Collectively, our results highlight the crucial role of the olfactory receptor Olfr15 in potentiating GSIS in pancreatic ß-cells, suggesting that Olfr15 may be an important therapeutic target in type 2 diabetes.

Pharmacological Inhibition of Caspase-1 Ameliorates Cisplatin-Induced Nephrotoxicity through Suppression of Apoptosis, Oxidative Stress, and Inflammation in Mice.

Caspase-1 is a proinflammatory caspase responsible for the proteolytic conversion of the precursor forms of interleukin-1ß to its active form and plays an important role in the pathogenesis of various inflammatory diseases. It was reported that genetic deficiency of caspase-1 prevented cisplatin-induced nephrotoxicity. However, whether pharmacological inhibition of caspase-1 also has a preventive effect against cisplatin-induced kidney injury has not been evaluated. In this study, we examined the effect of Ac-YVAD-cmk, a potent caspase-1-specific inhibitor, on renal function and histology in cisplatin-treated mice and explored its underlying mechanisms. We found that administration of Ac-YVAD-cmk effectively attenuated cisplatin-induced renal dysfunction, as evidenced by reduced plasma levels of blood urea nitrogen and creatinine, and histological abnormalities, such as tubular cell death, dilatation, and cast formation. Administration of Ac-YVAD-cmk inhibited caspase-3 activation as well as caspase-1 activation and attenuated apoptotic cell death, as assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling, in the kidneys of cisplatin-treated mice. Cisplatin-induced G2/M arrest of renal tubular cells was also reduced by caspase-1 inhibition. In addition, administration of Ac-YVAD-cmk reversed increased oxidative stress and depleted antioxidant capacity after cisplatin treatment. Moreover, increased macrophage accumulation and elevated expression of cytokines and chemokines were attenuated by caspase-1 inhibition. Taken together, these results suggest that caspase-1 inhibition by Ac-YVAD-cmk protects against cisplatin-induced nephrotoxicity through inhibition of renal tubular cell apoptosis, oxidative stress, and inflammatory responses. Our findings support the idea that caspase-1 may be a promising pharmacological target for the prevention of cisplatin-induced kidney injury.

Role of heterogeneous cell population on modulation of dendritic cell phenotype and activation of CD8 T cells for use in cell-based immunotherapies.

Dendritic cell (DC)-based immunotherapies have much utility in their ability to prime antigen-specific adaptive immune responses. However, there does not yet exist a consensus standard to how DCs should be primed. In this study, we aimed to determine the role of heterogeneous co-cultures, composed of both CD11c+ (DCs) and CD11c- cells, in combination with monophosphoryl lipid A (MPLA) stimulation on DC phenotype and function. Upon DC priming in different co-culture ratios, we observed reduced expression of MHCII and CD86 and increased antigen uptake among CD11c+ cells in a CD11c- dependent manner. DCs from all culture conditions were induced to mature by MPLA treatment, as determined by secretion of pro-inflammatory cytokines IL-12 and TNF-α. Antigen-specific stimulation of CD4+ T cells was not modulated by co-culture composition, in terms of proliferation nor levels of IFN-γ. However, the presence of CD11c- cells enhanced cross-presentation to CD8+ T cells compared to purified CD11c+ cells, resulting in increased cell proliferation along with higher IFN-γ production. These findings demonstrate the impact of cell populations present during DC priming, and point to the use of heterogeneous cultures of DCs and innate immune cells to enhance cell-mediated immunity.

Chitosan enhances nanoparticle delivery from the reproductive tract to target draining lymphoid organs.

To prime adaptive immune responses from the female reproductive tract (FRT), particulate antigens must be transported to draining lymph nodes (dLNs) since there are no local organized lymphoid structures equivalent to those found in the respiratory or gastrointestinal tracts. However, little is known about how to safely and effectively navigate successive barriers to transport such as crossing the epithelium and gaining access to migratory cells and lymphatic drainage that provide entry into dLNs. Here, we demonstrate that intravaginal pre-treatment with chitosan significantly facilitates translocation of nanoparticles (NPs) across the multilayered vaginal epithelium to target dLNs. In addition, chitosan pre-treatment was found to enhance NP associations with immunogenic antigen presenting cells in the vaginal submucosa. These observations indicate that chitosan may have great potential as an adjuvant for both local and systemic protective immunity against viral infections in the FRT.

An Information Retrieval Approach for Robust Prediction of Road Surface States.

Recently, due to the increasing importance of reducing severe vehicle accidents on roads (especially on highways), the automatic identification of road surface conditions, and the provisioning of such information to drivers in advance, have recently been gaining significant momentum as a proactive solution to decrease the number of vehicle accidents. In this paper, we firstly propose an information retrieval approach that aims to identify road surface states by combining conventional machine-learning techniques and moving average methods. Specifically, when signal information is received from a radar system, our approach attempts to estimate the current state of the road surface based on the similar instances observed previously based on utilizing a given similarity function. Next, the estimated state is then calibrated by using the recently estimated states to yield both effective and robust prediction results. To validate the performances of the proposed approach, we established a real-world experimental setting on a section of actual highway in South Korea and conducted a comparison with the conventional approaches in terms of accuracy. The experimental results show that the proposed approach successfully outperforms the previously developed methods.

Evidence for glucagon-like peptide-1 receptor signaling to activate ATP-sensitive potassium channels in pancreatic beta cells.

Glucagon-like peptide-1 (GLP-1) is a gut peptide that promotes insulin release from pancreatic beta cells. GLP-1 has been shown to confer glucose-insensitive beta cells with glucose sensitivity by modulation of the activity of the ATP-sensitive potassium (KATP) channel. The channel closing effect of GLP-1, interacting with corresponding G-protein-coupled receptors, has been well established; however, to our knowledge, no study has shown whether GLP-1 directly induces activation of beta-cell KATP channels. Here, we aimed to evaluate whether the activation of beta-cell KATP channels by GLP-1 exists and affects intracellular Ca(2+) levels ([Ca(2+)]i). KATP channel activity was measured in isolated rat pancreatic beta cells by whole-cell perforated patch-clamp recordings with a diazoxide-containing pipette solution. Changes in [Ca(2+)]i and the subcellular localization of KATP channels were observed using the calcium-sensitive dye fura-4/AM and anti-Kir6.2 antibodies in INS-1 beta cells, respectively. To eliminate the well-known inhibitory effects of GLP-1 on KATP channel activity, channels were fully inhibited by pretreatment with methyl pyruvate and epigallocatechin-3-gallate. In the pretreated beta cells, GLP-1 and exendin-4 promptly activated the channels, reducing [Ca(2+)]i. The phosphoinositide 3-kinase (PI3K) inhibitor LY294002 blocked the effects of GLP-1 on channel activity. Moreover, phosphatidylinositol-3,4,5-trisphosphate mimicked the effects of GLP-1. These results suggested that beta-cell GLP-1 receptor signaling involved activation of KATP channels via a PI3K-dependent pathway. This alternative mechanism of GLP-1 function may act as a negative feedback pathway, modulating the glucose-dependent GLP-1 inhibition on KATP channel activity.

Orexin A regulates plasma insulin and leptin levels in a time-dependent manner following a glucose load in mice.

AIMS/HYPOTHESIS: Orexin A (OXA) is a neuropeptide implicated in the regulation of arousal status and energy metabolism. Orexin receptors are expressed not only in the central nervous system but also in the pancreas and adipose tissue. However, little is known about the physiological function of orexins. This study investigated the role of exogenous OXA in blood glucose control after glucose load in mice. In addition, the effect of OXA on insulin secretion was also identified in mouse pancreatic beta cells. METHODS: Insulin secretion and intracellular Ca(2+) levels were measured in perifused mouse islets. To investigate the effects of exogenous OXA on blood glucose levels in vivo, intraperitoneal glucose tolerance tests were performed after a subcutaneous injection of OXA in normal and high-fat diet-induced diabetic mice. RESULTS: OXA significantly potentiated glucose-stimulated insulin secretion in vitro, which increased intracellular Ca(2+) levels, mainly through adenylate cyclase and ryanodine receptor activation. This Ca(2+)-dependent insulinotropic effect of OXA was blocked in Epac2 (Rapgef4)-deficient beta cells. After a glucose load in mice, exogenous OXA decreased blood glucose levels, compared with the control, by enhancing plasma insulin and decreasing plasma glucagon levels. Additionally, OXA caused a delayed increase in plasma leptin levels, resulting in lower plasma insulin levels when blood glucose levels fell to baseline. CONCLUSIONS/INTERPRETATION: These results suggest that OXA might be a critical regulator of insulin, glucagon and leptin secretion in response to glucose. Thus, exogenous OXA might have therapeutic potential in improving blood glucose control in patients with type 2 diabetes.

Protection of pancreatic ß-cells against glucotoxicity by short-term treatment with GLP-1.

Glucagon-like peptide-1 (GLP-1) reduces pancreatic ß-cell apoptosis in type 2 diabetes. Glucotoxiciy is a main cause of ß-cell apoptosis in type 2 diabetes. The aims of this study were to investigate the anti-apoptotic mechanisms of GLP-1 against glucotoxicity and whether physiological short-term treatment with GLP-1 can protect ß-cells from glucotoxicity-induced apoptosis. GLP-1 treatment for only 30 min alleviated high glucose-induced ß-cell apoptosis. The effect of GLP-1 was related with phosphoinositide 3-kinase (PI3K)/AKT-S473 phosphorylation. The increase in pAKT-S473 led to suppression of FoxO-1. GLP-1-induced AKT-S473 activation and FoxO-1 suppression were abolished by the selective inactivation of mTOR complex (mTORC) 2 using small interfering RNA directed towards the rapamycin-insensitive companion of mTOR. The protective effect of GLP-1 on ß-cell apoptosis was also abolished by the selective inactivation of mTORC2. Hence, the protective effect of GLP-1 against glucotoxicity may be mediated by FoxO-1 suppression through the PI3K/mTORC2/AKT-S473 phosphorylation. This report provides evidence that short-term treatment with GLP-1 is beneficial to protect against glucotoxicity-induced ß-cell apoptosis.

Chronic effects of neuroendocrine regulatory peptide (NERP-1 and -2) on insulin secretion and gene expression in pancreatic ß-cells.

Neuroendocrine regulatory peptides (NERP-1 and -2) are novel amidated peptides derived from VGF, a polypeptide secreted from neurons and endocrine cells through a regulated pathway. Dr. Nakazato Masamitsu reported that NERP-1 and -2 may have a local modulator function on the human endocrine system, and clearly showed expression of NERP-1 and -2 in human pancreas islets. Based on these data, we investigated the alteration of insulin secretion, insulin granule-related protein, and pancreas-specific transcription factors in response to NERPs expression. We confirmed the expression of NERP-1 and -2 in the pancreas of a human diabetes patient, in addition to diabetic animal models. When INS1 cells and primary rat islets were incubated with 10nM NERPs for 3 days, glucose-stimulated insulin secretion levels were blunted by NERP-1 and -2. The number of insulin granules released from the readily releasable pool, which is associated with the first phase of glucose-stimulated insulin release, was decreased by NERP-1 and -2. Insulin granule-related proteins and mRNAs were down-regulated by NERP-2 treatment. NERP-2 decreased the expression of BETA2/NeuroD and insulin and controlled the nucleo-cytoplasmic translocation of FOXO1 and Pdx-1. We observed that NERP-2 levels were dramatically increased in diabetic pancreas. In conclusion, NERP-2 may play an important role in insulin secretion through the regulation of insulin secretory granules and ß-cell transcription factors. In addition, NERP-2 expression is increased in diabetic conditions. Therefore, we suggest that NERPs may be potent endogenous suppressors of glucose-dependent insulin secretion.

Melatonin ameliorates ER stress-mediated hepatic steatosis through miR-23a in the liver.

The endoplasmic reticulum (ER) stress induces hepatic steatosis and inflammation in the liver. Although melatonin ameliorates ER stress-target genes, it remains unknown whether melatonin protects against hepatic steatosis as well as inflammation through regulation of miRNA. MicroRNAs have been identified as pivotal regulators in the field of gene regulation and their dysfunctions are a common feature in a variety of metabolic diseases. Especially, among miRNAs, miR-23a has been shown to regulate ER stress. Herein, we investigated the crucial roles of melatonin in hepatic steatosis and inflammation in vivo. Tunicamycin challenge caused increase of hepatic triglyceride and intracellular calcium levels through activation of ER stress, whereas these phenomena were partially disrupted by melatonin. We also demonstrated that expression of miR-23a stimulated with tunicamycin was rescued by melatonin treatment, resulting in reduced ER stress in primary hepatocytes. Overall, these results suggest a new function of melatonin that is involved in ameliorating ER stress-induced hepatic steatosis and inflammation by attenuating miR-23a. Melatonin may be useful as a pharmacological agent to protect against hepatic metabolic diseases due to its ability to regulate expression of miR-23a.

Improved application of the electrophoretic tissue clearing technology, CLARITY, to intact solid organs including brain, pancreas, liver, kidney, lung, and intestine.

BACKGROUND: Mapping of tissue structure at the cellular, circuit, and organ-wide scale is important for understanding physiological and biological functions. A bio-electrochemical technique known as CLARITY used for three-dimensional anatomical and phenotypical mapping within transparent intact tissues has been recently developed. This method provided a major advance in understanding the structure-function relationships in circuits of the nervous system and organs by using whole-body clearing. Thus, in the present study, we aimed to improve the original CLARITY procedure and developed specific CLARITY protocols for various intact organs. RESULTS: We determined the optimal conditions for reducing bubble formation, discoloration, and depositing of black particles on the surface of tissue, which allowed production of clearer organ images. We also determined the appropriate replacement cycles of clearing solution for each type of organ, and convincingly demonstrated that 250-280 mA is the ideal range of electrical current for tissue clearing. We then acquired each type of cleared organs including brain, pancreas, liver, lung, kidney, and intestine. Additionally, we determined the images of axon fibers of hippocampal region, the Purkinje layer of cerebellum, and vessels and cellular nuclei of pancreas. CONCLUSIONS: CLARITY is an innovative biochemical technology for the structural and molecular analysis of various types of tissue. We developed improved CLARITY methods for clearing of the brain, pancreas, lung, intestine, liver, and kidney, and identified the appropriate experimental conditions for clearing of each specific tissue type. These optimized methods will be useful for the application of CLARITY to various types of organs.