109 research outputs found
Broussonetia papyrifera Root Bark Extract Exhibits Anti-inflammatory Effects on Adipose Tissue and Improves Insulin Sensitivity Potentially Via AMPK Activation
The chronic low-grade inflammation in adipose tissue plays a causal role in obesity-induced insulin resistance and its associated pathophysiological consequences. In this study, we investigated the effects of extracts of Broussonetia papyrifera root bark (PRE) and its bioactive components on inflammation and insulin sensitivity. PRE inhibited TNF-alpha-induced NF-kappa B transcriptional activity in the NF-kappa B luciferase assay and pro-inflammatory genes' expression by blocking phosphorylation of I kappa B and NF-kappa B in 3T3-L1 adipocytes, which were mediated by activating AMPK. Ten-week-high fat diet (HFD)-fed C57BL6 male mice treated with PRE had improved glucose intolerance and decreased inflammation in adipose tissue, as indicated by reductions in NF-kappa B phosphorylation and pro-inflammatory genes' expression. Furthermore, PRE activated AMP-activated protein kinase (AMPK) and reduced lipogenic genes' expression in both adipose tissue and liver. Finally, we identified broussoflavonol B (BF) and kazinol J (KJ) as bioactive constituents to suppress pro-inflammatory responses via activating AMPK in 3T3-L1 adipocytes. Taken together, these results indicate the therapeutic potential of PRE, especially BF or KJ, in metabolic diseases such as obesity and type 2 diabetes
PPM1A Controls Diabetic Gene Programming through Directly Dephosphorylating PPAR?? at Ser273
Peroxisome proliferator-activated receptor gamma (PPAR gamma) is a master regulator of adipose tissue biology. In obesity, phosphorylation of PPAR gamma at Ser273 (pSer273) by cyclin-dependent kinase 5 (CDK5)/extracellular signal-regulated kinase (ERK) orchestrates diabetic gene reprogramming via dysregulation of specific gene expression. Although many recent studies have focused on the development of non-classical agonist drugs that inhibit the phosphorylation of PPAR gamma at Ser273, the molecular mechanism of PPAR gamma dephosphorylation at Ser273 is not well characterized. Here, we report that protein phosphatase Mg2+/Mn2+-dependent 1A (PPM1A) is a novel PPAR gamma phosphatase that directly dephosphorylates Ser273 and restores diabetic gene expression which is dysregulated by pSer273. The expression of PPM1A significantly decreases in two models of insulin resistance: diet-induced obese (DIO) mice and db/db mice, in which it negatively correlates with pSer273. Transcriptomic analysis using microarray and genotype-tissue expression (GTEx) data in humans shows positive correlations between PPM1A and most of the genes that are dysregulated by pSer273. These findings suggest that PPM1A dephosphorylates PPAR gamma at Ser273 and represents a potential target for the treatment of obesity-linked metabolic disorders
Effect of donor–recipient size mismatch on long-term graft survival in pediatric kidney transplantation: a multicenter cohort study
Background Donor–recipient size mismatching is commonly occurs in pediatric kidney transplantation (KT). However, its effect on graft survival remains unknown. This study aimed to determine the effect of donor–recipient size mismatch on the long-term survival rate of transplant kidneys in pediatric KT. Methods A total of 241 pediatric patients who received KT were enrolled. The medical records of all patients were retrospectively reviewed, and the correlation between donor–recipient size mismatch and graft function and long-term graft outcome was analyzed according to donor–recipient size mismatch. Results Recipients and donors’ mean body weight at the time of KT were 34.31 ± 16.85 and 56.53 ± 16.73 kg, respectively. The mean follow-up duration was 96.49 ± 52.98 months. A significant positive correlation was observed between donor–recipient body weight ratio (DRBWR) or donor–recipient body surface area ratio (DRBSR) and graft function until 1 year after KT. However, this correlation could not be confirmed at the last follow-up. The results of long-term survival analysis using Fine and Gray’s subdistribution hazard model showed no significant difference of the survival rate of the transplant kidney according to DRBWR or DRBSR. Conclusion Donor–recipient size mismatch in pediatric KT is not an important factor in determining the long-term prognosis of transplant kidneys
Etanercept treatment for pediatric toxic epidermal necrolysis induced by deflazacort: a case report and literature review
Toxic epidermal necrolysis (TEN) is a life-threatening mucocutaneous disorder commonly caused by drugs. TEN is often treated with corticosteroids, intravenous immunoglobulin (IVIG), or cyclosporine; however, the efficacy of these treatments is controversial. Etanercept (a TNF-α antagonist) was proven to decrease skin-healing time in a randomized clinical trial. Herein, we report the case of a 44-month-old boy who developed TEN due to deflazacort as the probable culprit drug and was successfully treated with etanercept. The patient presented to the emergency department complaining of erythematous maculopapular rashes and vesicles all over the face and body, with vesicles on the hands, feet, and trunk. Symptoms started 4 days before presentation, with edema of the upper lip, which progressed to erythematous macules over the body. He was started on deflazacort for nephrotic syndrome 21 days before the visit. Approximately 20% of the body surface area (BSA) was covered by vesicular lesions. Under the diagnosis of Steven Johnson syndrome/TEN, deflazacort was discontinued, and intravenous dexamethasone (1.5 mg/kg/day), a 5-day course of IVIG (0.4 mg/kg/day), and cyclosporine (3 mg/kg/day) were administered. The lesions seemed to be stationary for 3 days, but on the 6th day of hospitalization, when IVIG was discontinued, the vesicular lesions progressed to approximately 60% of the BSA. Etanercept 0.8 mg/kg was administered subcutaneously. Lesions stopped progressing, and bullous lesions started epithelialization. However, on the 15th day, around 30% of the BSA was still involved; thus, a second dose of etanercept was administered. No acute or sub-acute complications were observed. In conclusion, the use of etanercept in children with TEN that is not controlled with conventional therapy is both effective and safe
Clinical and laboratory findings associated with severe scrub typhus
<p>Abstract</p> <p>Background</p> <p>Scrub typhus is a mite-borne bacterial infection of humans caused by <it>Orientia tsutsugamushi </it>that causes a generalized vasculitis that may involve the tissues of any organ system. The aim of this study was to identify factors associated to severe complications from scrub typhus.</p> <p>Methods</p> <p>We conducted this prospective, case-control study on scrub typhus patients who presented to the Department of Internal Medicine at Chosun University Hospital between September, 2004 and December, 2006. Cases were 89 scrub typhus patients with severe complications and controls were 119 scrub typhus patients without severe complications.</p> <p>Results</p> <p>There were significant differences in the absence of eschar, white blood cell (WBC) counts, hemoglobin, albumin, serum creatinine, fibrinogen, C-reactive protein (CRP), and active partial thromboplastin time (aPTT) between the two groups. Multivariate analysis demonstrated that only the following four factors were significantly associated with the severe complications of scrub typhus: (1) age ≥ 60 years (odd ratio [OR] = 3.13, <it>P </it>= 0.002, confidence interval [CI] = 1.53-6.41), (2) the absence of eschar (OR = 6.62, <it>P </it>= 0.03, CI = 1.22-35.8, (3) WBC counts > 10, 000/mm3 (OR = 3.6, <it>P </it>= 0.001, CI = 1.65-7.89), and (4) albumin ≤ 3.0 g/dL (OR = 5.01, <it>P </it>= 0.004, CI = 1.69-14.86).</p> <p>Conclusions</p> <p>Our results suggest that clinicians should be aware of the potential for complications, when scrub typhus patients are older (≥ 60 years), presents without eschar, or laboratory findings such as WBC counts > 10, 000/mm3, and serum albumin level ≤ 3.0 g/dL. Close observation and intensive care for scrub typhus patients with the potential for complications may prevent serious complications with subsequent reduction in its mortality rate.</p
Autophagy deficiency leads to protection from obesity and insulin resistance by inducing Fgf21 as a mitokine
Despite growing interest and a recent surge in papers, the role of autophagy in glucose and lipid metabolism is unclear. We produced mice with skeletal muscle–specific deletion of Atg7 (encoding autophagy-related 7). Unexpectedly, these mice showed decreased fat mass and were protected from diet-induced obesity and insulin resistance; this phenotype was accompanied by increased fatty acid oxidation and browning of white adipose tissue (WAT) owing to induction of fibroblast growth factor 21 (Fgf21). Mitochondrial dysfunction induced by autophagy deficiency increased Fgf21 expression through induction of Atf4, a master regulator of the integrated stress response. Mitochondrial respiratory chain inhibitors also induced Fgf21 in an Atf4-dependent manner. We also observed induction of Fgf21, resistance to diet-induced obesity and amelioration of insulin resistance in mice with autophagy deficiency in the liver, another insulin target tissue. These findings suggest that autophagy deficiency and subsequent mitochondrial dysfunction promote Fgf21 expression, a hormone we consequently term a 'mitokine', and together these processes promote protection from diet-induced obesity and insulin resistance
Modelling charge transport and electro-optical characteristics of quantum dot light-emitting diodes
Abstracts: Quantum dot light-emitting diodes (QD-LEDs) are considered as competitive candidate for next-generation displays or lightings. Recent advances in the synthesis of core/shell quantum dots (QDs) and tailoring procedures for achieving their high quantum yield have facilitated the emergence of high-performance QD-LEDs. Meanwhile, the charge-carrier dynamics in QD-LED devices, which constitutes the remaining core research area for further improvement of QD-LEDs, is, however, poorly understood yet. Here, we propose a charge transport model in which the charge-carrier dynamics in QD-LEDs are comprehensively described by computer simulations. The charge-carrier injection is modelled by the carrier-capturing process, while the effect of electric fields at their interfaces is considered. The simulated electro-optical characteristics of QD-LEDs, such as the luminance, current density and external quantum efficiency (EQE) curves with varying voltages, show excellent agreement with experiments. Therefore, our computational method proposed here provides a useful means for designing and optimising high-performance QD-LED devices
The E3 ubiquitin ligase TRIM25 regulates adipocyte differentiation via proteasomemediated degradation of PPAR gamma
Peroxisome proliferator-activated receptor gamma (PPAR??) is a ligand-dependent transcription factor that regulates adipocyte differentiation and glucose homeostasis. The transcriptional activity of PPAR?? is regulated not only by ligands but also by post-translational modifications (PTMs). In this study, we demonstrate that a novel E3 ligase of PPAR??, tripartite motif-containing 25 (TRIM25), directly induced the ubiquitination of PPAR??, leading to its proteasome-dependent degradation. During adipocyte differentiation, both TRIM25 mRNA and protein expression significantly decreased and negatively correlated with the expression of PPAR??. The stable expression of TRIM25 reduced PPAR?? protein levels and suppressed adipocyte differentiation in 3T3-L1 cells. In contrast, the specific knockdown of TRIM25 increased PPAR?? protein levels and stimulated adipocyte differentiation. Furthermore, TRIM25-knockout mouse embryonic fibroblasts (MEFs) exhibited an increased adipocyte differentiation capability compared with wild-type MEFs. Taken together, these data indicate that TRIM25 is a novel E3 ubiquitin ligase of PPAR?? and that TRIM25 is a novel target for PPAR??-associated metabolic diseases
Corrigendum: Mineral bone disorder in children with chronic kidney disease: data from the KNOW-Ped CKD (Korean cohort study for outcome in patients with pediatric chronic kidney disease) study
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