The Long-Term Outcomes and Risk Factors of Complications After Fontan Surgery: From the Korean Fontan Registry (KFR).

BACKGROUND AND OBJECTIVES: This study aimed to analyze the outcomes of Fontan surgery in the Republic of Korea, as there were only a few studies from Asian countries. METHODS: The medical records of 1,732 patients who underwent Fontan surgery in 10 cardiac centers were reviewed. RESULTS: Among them, 1,040 (58.8%) were men. The mean age at Fontan surgery was 4.3±4.2 years, and 395 (22.8%) patients presented with heterotaxy syndrome. According to the types of Fontan surgery, 157 patients underwent atriopulmonary (AP) type; 303, lateral tunnel (LT) type; and 1,266, extracardiac conduit (ECC) type. The overall survival rates were 91.7%, 87.1%, and 74.4% at 10, 20, and 30 years, respectively. The risk factors of early mortality were male, heterotaxy syndrome, AP-type Fontan surgery, high mean pulmonary artery pressure (mPAP) in pre-Fontan cardiac catheterization, and early Fontan surgery year. The risk factors of late mortality were heterotaxy syndrome, genetic disorder, significant atrioventricular valve regurgitation (AVVR) before Fontan surgery, high mPAP in pre-Fontan cardiac catheterization, and no fenestration. CONCLUSIONS: In Asian population with a high incidence of heterotaxy syndrome, the heterotaxy syndrome was identified as the poor prognostic factors for Fontan surgery. The preoperative low mPAP and less AVVR are associated with better early and long-term outcomes of Fontan surgery.

Dienogest in endometriosis treatment: A narrative literature review.

Endometriosis is characterized by the implantation of endometrial cells outside the uterus. This hormone-dependent disease is highly prevalent among women of reproductive age. Clinical symptoms of endometriosis include dysmenorrhea, pelvic pain, and infertility, which can negatively impact the overall quality of life of those affected. The medical treatment of endometriosis serves as an important therapeutic option, aimed at alleviating pain associated with the condition and suppressing the growth of endometriotic lesions. As such, it is employed as an adjuvant therapy following surgery or an empirical treatment after the clinical diagnosis of endometriosis. Dienogest, a fourth-generation progestin, has received approval for the treatment of endometriosis in many countries. A growing body of evidence has demonstrated its efficacy in managing endometriosis-associated pain, preventing symptoms, and reducing lesion recurrence. In this review, we examine the clinical efficacy, safety, and tolerability of dienogest in treating endometriosis. We also provide updated findings, drawing from clinical studies that focus on the long-term use of this medication in patients with endometriosis.

Suppression of Pro-Inflammatory M1 Polarization of LPS-Stimulated RAW 264.7 Macrophage Cells by Fucoxanthin-Rich Sargassum hemiphyllum.

Macrophages play an important role in managing the onset and progression of chronic inflammatory diseases. The primary objective of this study is to explore the antioxidant potential and anti-inflammatory properties of Sargassum hemiphyllum ethanol extract (SHE) and its fraction. SHE and its five constituent fractions were assessed for overall antioxidant capabilities and inhibitory effects on LPS-induced inflammation by modulating macrophages polarization in both RAW 264.7 macrophages and bone-marrow-derived macrophages (BMDM). Among the organic solvent fractions of SHE, the ethyl acetate fraction displayed the highest total phenolic content and total antioxidant capacity. Notably, the n-hexane (Hex) fraction showed the most substantial suppression of LPS-induced tumor necrosis factor α secretion in BMDM among the five fractions of SHE. The SHE and Hex fraction significantly reduced the heightened expression of pro-inflammatory cytokines and inflammation-inducible enzymes induced by LPS in RAW 264.7 macrophages. In particular, the SHE and Hex fraction inhibited M1 macrophage polarization by reducing the mRNA expression of M1 macrophage markers in macrophages that were polarized toward the M1 phenotype. Furthermore, the SHE and Hex fraction attenuated the induction in nuclear factor E2-related factor 2 and its target genes, which was accompanied by an alteration in antioxidant gene expression in M1-polarized BMDM. The findings suggest that both SHE and its Hex fraction exhibit inhibitory effects on LPS-triggered inflammation and oxidative stress by modulating the polarization of M1 macrophages within macrophage populations.

Mylohyoid muscle revisited: anatomic features with clinical implications in dentistry / Revisión del músculo milohioideo: características anatómica con implicaciones clínicas en odontología

SUMMARY: The mylohyoid muscle, one of the suprahyoid group, forms the floor of the mouth. Its main function is swallowing. It is a margin between the sublingual and the submandibular spaces and is important in the pathway of oral and maxillofacial infection. In prosthodontics, it is one of anatomic landmarks that limits the lingual margin of the mandibular denture. Currently, the muscle receives much interest in the fields of maxillofacial reconstruction and rejuvenation. The hemorrhagic issue around the mandibular lingual region is usually involved with the mylohyoid especially in the dental implant installation. This review covers anatomic features of the mylohyoid muscle with diverse clinical implications.

RESUMEN: El músculo milohioideo es un músculo del grupo suprahioideo que forma el piso de la cavidad oral. Su función principal es la deglución. Es conocido como un límite entre los espacios sublingual y submandibular y es importante en la vía de infección oral y maxilofacial. En la prostodoncia, es uno de los hitos anatómicos que limita el margen lingual de la dentadura mandibular. Actualmente, el músculo recibe mucho interés en los campos de la reconstrucción y el rejuvenecimiento maxilofacial. El problema hemorrágico alrededor de la región lingual mandibular generalmente está relacionado con el músculo milohioideo, especialmente en la instalación de implantes dentales. Esta revisión cubre las características anatómicas del músculo milohioideo con diversas implicaciones clínicas.

Association of Estimated Cardiorespiratory Fitness in Midlife With Cardiometabolic Outcomes and Mortality.

Importance: The associations of estimated cardiorespiratory fitness (eCRF) during midlife with subclinical atherosclerosis, arterial stiffness, incident cardiometabolic disease, and mortality are not well understood. Objective: To examine associations of midlife eCRF with subclinical atherosclerosis, arterial stiffness, incident cardiometabolic disease, and mortality. Design, Setting, and Participants: This cohort study included 2962 participants in the Framingham Study Second Generation (conducted between 1979 and 2001). Data were analyzed from January 2020 to June 2020. Exposures: eCRF was calculated using sex-specific algorithms (including age, body mass index, waist circumference, physical activity, resting heart rate, and smoking) and was categorized as: (1) tertiles of standardized eCRF at examination cycle 7 (1998 to 2001); (2) tertiles of standardized average eCRF between examination cycles 2 and 7 (1979 to 2001); and (3) eCRF trajectories between examination cycles 2 and 7, with the lowest tertile or trajectory (ie, low eCRF) as referent group. Main Outcomes and Measures: Subclinical atherosclerosis (carotid intima-media thickness [CIMT], coronary artery calcium [CAC] score); arterial stiffness (carotid-femoral pulse wave velocity [-1000/CFPWV]); incident hypertension, diabetes, chronic kidney disease (CKD), cardiovascular disease (CVD), and mortality after examination cycle 7. Results: A total of 2962 participants were included in this cohort study (mean [SD] age, 61.5 [9.2] years; 1562 [52.7%] women). The number of events or participants at risk after examination cycle 7 (at a mean follow-up of 15 years) was 728 of 1506 for hypertension, 214 of 2268 for diabetes, 439 of 2343 for CKD, 500 of 2608 for CVD, and 770 of 2962 for mortality. Compared with the low eCRF reference value, high single examination eCRF was associated with lower CFPWV (ß [SE], -11.13 [1.33] ms/m) and CIMT (ß [SE], -0.12 [0.05] mm), and lower risk of hypertension (hazard ratio [HR], 0.63; 95% CI, 0.46-0.85), diabetes (HR, 0.38; 95% CI, 0.23-0.62), and CVD (HR, 0.71; 95% CI, 0.53-0.95), although it was not associated with CKD or mortality. Similarly, compared with the low eCRF reference, high eCRF trajectories and mean eCRF were associated with lower CFPWV (ß [SE], -11.85 [1.89] ms/m and -10.36 [1.54] ms/m), CIMT (ß [SE], -0.19 [0.06] mm and -0.15 [0.05] mm), CAC scores (ß [SE], -0.67 [0.25] AU and -0.63 [0.20] AU), and lower risk of hypertension (HR, 0.54; 95% CI, 0.34-0.87 and HR, 0.48; 95% CI, 0.34-0.68), diabetes (HR, 0.27; 95% CI, 0.15-0.48 and HR, 0.31; 95% CI, 0.18-0.54), CKD (HR, 0.63; 95% CI, 0.40-0.97 and HR, 0.64; 95% CI, 0.44-0.94), and CVD (HR, 0.46; 95% CI, 0.31-0.68 and HR, 0.43; 95% CI, 0.30-0.60). Compared with the reference value, a high eCRF trajectory was associated with lower risk of mortality (HR, 0.69; 95% CI, 0.50-0.95). Conclusions and Relevance: In this cohort study, higher midlife eCRF was associated with lower burdens of subclinical atherosclerosis and vascular stiffness, and with a lower risk of hypertension, diabetes, chronic kidney disease, cardiovascular disease, and mortality. These findings suggest that midlife eCRF may serve as a prognostic marker for subclinical atherosclerosis, arterial stiffness, cardiometabolic health, and mortality in later life.

Conjoint Associations of Adherence to Physical Activity and Dietary Guidelines With Cardiometabolic Health: The Framingham Heart Study.

Background The conjoint associations of adherence to the recent physical activity and dietary guidelines with the metabolic syndrome (MetS) are incompletely understood. Methods and Results We evaluated 2379 FHS (Framingham Heart Study) Third Generation participants (mean age, 47 years; 54.4% women) attending examination cycle 2. We examined the cross-sectional relations of adherence to the 2018 Physical Activity Guidelines for Americans (binary; moderate-to-vigorous physical activity ≥150 versus <150 min/wk) and 2015 Dietary Guidelines for Americans (binary; 2015 Dietary Guidelines for Americans Adherence Index ≥median versus

Correlation between preoperative somatosensory evoked potentials and intraoperative neurophysiological monitoring in spinal cord tumors.

Intraoperative neurophysiological monitoring (IONM) is widely used in spinal cord tumors (SCTs) removal surgery. This study mainly hypothesized that patients with prolonged latency of preoperative somatosensory evoked potentials (preSEPLat) would have more deteriorated intraoperative evoked potentials. Among 506 patients who underwent SCTs removal surgery, 74 underwent both preSEPs and IONM. The correlation between preSEPLat and intraoperative SEPs (ioSEPs) was mainly analyzed, and subgroup analysis according to anatomical type was also conducted. Secondly, whether preSEPLat related to intraoperative motor evoked potentials (ioMEPs) or postoperative motor deterioration (PMD) was analyzed. In addition, risk factors for PMD were examined among anatomical factors, including operation level, tumor-occupying area ratio, and anatomical type, as well as electrophysiological factors, such as preSEPLat, ioSEPs, and ioMEPs. Changes in ioSEP and ioMEP were considered significant even if they were recovered before the end of the monitoring. Patients with prolonged preSEPLat were more likely to have significant ioSEP changes for intradural-extramedullary (IDEM) but not for intramedullary or extradural tumors. The anatomical type and tumor-occupying area ratio were prognostic factors for transient PMD, while the ioSEPs were the only prognostic factor for persisted PMD over 4 weeks after surgery. PreSEPs are helpful in predicting the significant changes in ioSEPs during IDEM tumor removal surgery. The tumor-occupying area ratio and anatomical type are contributing factors for the transient PMD, whereas ioSEPs are prognostic factors in predicting the PMD that persists over 4 weeks after SCTs removal surgery. To our knowledge, this is the first study that mainly focused on the correlations of preoperative and intraoperative evoked potentials.

Dietary Patterns, Ceramide Ratios, and Risk of All-Cause and Cause-Specific Mortality: The Framingham Offspring Study.

BACKGROUND: Prior evidence suggests that diet modifies the association of blood ceramides with the risk of incident cardiovascular disease (CVD). It remains unknown if diet quality modifies the association of very long-chain-to-long-chain ceramide ratios with mortality in the community. OBJECTIVES: Our objectives were to determine how healthy dietary patterns associate with blood ceramide concentrations and to examine if healthy dietary patterns modify associations of ceramide ratios (C22:0/C16:0 and C24:0/C16:0) with all-cause and cause-specific mortality. METHODS: We examined 2157 participants of the Framingham Offspring Study (mean age = 66 y, 55% women). Blood ceramides were quantified using a validated assay. We evaluated prospective associations of the Dietary Guidelines Adherence Index (DGAI) and Mediterranean-style Diet Score (MDS) with incidence of all-cause and cause-specific mortality using Cox proportional hazards models. Cross-sectional associations of the DGAI and MDS with ceramides were evaluated using multivariable linear regression models. RESULTS: The C22:0/C16:0 and C24:0/C16:0 ceramide ratios were inversely associated with all-cause, CVD, and cancer mortality; multivariable-adjusted HRs (95% CIs) were 0.73 (0.67, 0.80) and 0.70 (0.63, 0.77) for all-cause mortality, 0.74 (0.60, 0.90) and 0.69 (0.55, 0.86) for CVD mortality, and 0.75 (0.65, 0.87) and 0.75 (0.64, 0.88) for cancer mortality, respectively. Inverse associations of the C22:0/C16:0 and C24:0/C16:0 ceramide ratios with cancer mortality were attenuated among individuals with a higher diet quality (DGAI or MDS above the median, all P-interaction ≤0.1). The DGAI and MDS had distinct associations with ceramide ratios (DGAI: lower C22:0/C16:0 across quartiles; MDS: higher C24:0/C16:0 across quartiles; all P-trend ≤0.01). CONCLUSION: In our community-based sample, ceramide ratios (C22:0/C16:0 and C24:0/C16:0) were associated with a lower risk of all-cause and cause-specific mortality. Further, we observed that a higher overall diet quality attenuates the association between blood ceramide ratios and cancer mortality and that dietary patterns have distinct relations with ceramide ratios.

End-of-Life Care of Hospitalized Children with Advanced Heart Disease.

BACKGROUND: Despite improvements in palliative care for critically ill children, the characteristics of end-of-life care for pediatric patients with advanced heart disease are not well-known. We investigated these characteristics among hospitalized children with advanced heart disease in a tertiary referral center in Korea. METHODS: We retrospectively reviewed the records of 136 patients with advanced heart disease who died in our pediatric department from January 2006 through December 2013. RESULTS: The median age of patients at death was 10.0 months (range 1 day-28.3 years). The median duration of the final hospitalization was 16.5 days (range 1-690 days). Most patients (94.1%) died in the intensive care unit and had received mechanical ventilation (89.7%) and inotropic agents (91.2%) within 24 hours of death. The parents of 74 patients (54.4%) had an end-of-life care discussion with their physician, and the length of stay of these patients in the intensive care unit and in hospital was longer. Of the 90 patients who had been hospitalized for 7 days or more, the parents of 54 patients (60%) had a documented end-of-life care discussion. The time interval from the end-of-life care discussion to death was 3 days or less for 25 patients. CONCLUSION: Children dying of advanced heart disease receive intensive treatment at the end of life. Discussions regarding end-of-life issues are often postponed until immediately prior to death. A pediatric palliative care program must be implemented to improve the quality of death in pediatric patients with heart disease.

¡Activate Ya! Co-learning about school-based tobacco prevention and physical activity promotion in secondary school students in Uruguay.

PURPOSE: ¡Activate Ya! was a group-randomized controlled intervention trial aimed at developing and evaluating the impact of a school-based intervention on preventing cigarette smoking and promoting physical activity (PA) in secondary school students in Uruguay. Secondary aims were to evaluate the program's impact on students' smoking- and PA-related psychosocial risk and protective factors. METHODS: Sixteen schools and n = 654 students participated in the study. The one-year intervention included a classroom-based curriculum, an afterschool program, activity breaks, and final showcase event. A self-administered questionnaire measured outcomes at three time points. Fixed effects regression models tested for differences in outcomes by study condition. RESULTS: While positive intervention effects were found for selected psychosocial-related smoking outcomes, no impact on past-year smoking or smoking susceptibility was detected. Past 7-day PA, measured by the PAQ-C, was significantly higher among intervention school students overall (p = .048) and for girls (p = .03) at posttest, and intervention girls reported significantly higher athletic identity PA competence, friend and teacher PA support at posttest, and PA enjoyment at follow-up (p < .05). CONCLUSION: The positive short-term effects of ¡Activate Ya! on PA and related outcomes for girls support the utility of school-based health promotion in Uruguay. Additional research is needed to determine the most effective strategies to prevent tobacco use among students and promote PA among boys in this setting.

Exact association test for small size sequencing data.

BACKGROUND: Recent statistical methods for next generation sequencing (NGS) data have been successfully applied to identifying rare genetic variants associated with certain diseases. However, most commonly used methods (e.g., burden tests and variance-component tests) rely on large sample sizes. Notwithstanding, due to its-still high cost, NGS data is generally restricted to small sample sizes, that cannot be analyzed by most existing methods. METHODS: In this work, we propose a new exact association test for sequencing data that does not require a large sample approximation, which is applicable to both common and rare variants. Our method, based on the Generalized Cochran-Mantel-Haenszel (GCMH) statistic, was applied to NGS datasets from intraductal papillary mucinous neoplasm (IPMN) patients. IPMN is a unique pancreatic cancer subtype that can turn into an invasive and hard-to-treat metastatic disease. RESULTS: Application of our method to IPMN data successfully identified susceptible genes associated with progression of IPMN to pancreatic cancer. CONCLUSIONS: Our method is expected to identify disease-associated genetic variants more successfully, and corresponding signal pathways, improving our understanding of specific disease's etiology and prognosis.

The analgesic potency dose of remifentanil to minimize stress response induced by intubation and measurement uncertainty of Surgical Pleth Index.

BACKGROUND: The aim of this study was to evaluate the analgesic potency dose of remifentanil to maintain Surgical Pleth Index (SPI) values at less than 50 after intubation in patients undergoing general anesthesia with target-controlled infusion of propofol and remifentanil. METHODS: We randomly allocated 120 patients to receive one of three remifentanil target effect-site concentrations (5, 7, or 9 ng×mL-1) during intubation. The target effect-site concentrations of propofol were adjusted within a range of 2.5-3 µg×mL-1 to maintain bispectral index values at less than 60 during anesthesia induction. A reusable SPI sensor was placed on the index finger of the arm, and the SPI values were continuously recorded. The predicted probability for maintaining the SPI values at less than 50 after intubation against the cumulative amount of remifentanil was analyzed using logistic regression. The measurands were the baseline SPI value in patients without pain scheduled for surgery, and the maximal SPI value after intubation in patients receiving remifentanil with a target effect-site concentration of 7 ng×mL-1. RESULTS: The estimated cumulative amount of remifentanil associated with a 50% and 95% probability of maintaining the SPI values at less than 50 after intubation were 135.0 µg and 330.4 µg, respectively. The estimated expanded uncertainty for the baseline and maximal SPI values after intubation in patients scheduled for surgery were 54.9±44.4 and 54.1±37.9, respectively, which corresponded to a confidence level of approximately 95%. CONCLUSIONS: The analgesic potency dose of remifentanil to maintain SPI values at less than 50 after intubation was 135.0 µg.

Intraoperative Neurophysiological Monitoring for Spinal Cord Tumor Surgery: Comparison of Motor and Somatosensory Evoked Potentials According to Tumor Types.

OBJECTIVE: To identify which combination of motor evoked potentials (MEPs) and somatosensory evoked potentials (SEPs) is most reliable for postoperative motor deterioration during spinal cord tumor surgery, according to anatomical and pathologic type. METHODS: MEPs and SEPs were monitored in patients who underwent spinal cord tumor surgery between November 2012 and August 2016. Muscle strength was examined in all patients before surgery, within 48 hours postoperatively and 4 weeks later. We analyzed sensitivity, specificity, positive and negative predictive values of each significant change in SEPs and MEPs. RESULTS: The overall sensitivity and specificity of SEPs or MEPs were 100% and 61.3%, respectively. The intraoperative MEP monitoring alone showed both higher sensitivity (67.9%) and specificity (83.2%) than SEP monitoring alone for postoperative motor deterioration. Two patients with persistent motor deterioration had significant changes only in SEPs. There are no significant differences in reliabilities between anatomical types, except with hemangioma, where SEPs were more specific than MEPs for postoperative motor deterioration. Both overall positive and negative predictive values of MEPs were higher than the predictive values of SEPs. However, the positive predictive value was higher by the dual monitoring of MEPs and SEPs, compared to MEPs alone. CONCLUSION: For spinal cord tumor surgery, combined MEP and SEP monitoring showed the highest sensitivity for the postoperative motor deterioration. Although MEPs are more specific than SEPs in most types of spinal cord tumor surgery, SEPs should still be monitored, especially in hemangioma surgery.

Safety and efficacy of the off-label use of milrinone in pediatric patients with heart diseases.

BACKGROUND AND OBJECTIVES: Milrinone is often used in children to treat acute heart failure and prevent low cardiac output syndrome after cardiac surgery. Due to the lack of studies on the long-term milrinone use in children, the objective of this study was to assess the safety and efficacy of the current patterns of milrinone use for ≥3 days in infants and children with heart diseases. SUBJECTS AND METHODS: We retrospectively reviewed the medical records of patients aged <13 years who received milrinone for ≥3 days from January 2005 to December 2012. Patients' characteristics including age, sex, height, weight, and body surface area were recorded. The following parameters were analyzed to identify the clinical application of milrinone: initial infusion rate, maintenance continuous infusion rate, total duration of milrinone therapy, and concomitantly infused inotropes. The safety of milrinone was determined based on the occurrence of adverse events such as hypotension, arrhythmia, chest pain, headache, hypokalemia, and thrombocytopenia. RESULTS: We assessed 730 admissions (684 patients) during this period. Ventricular septal defects were the most common diagnosis (42.4%) in these patients. Milrinone was primarily used after cardiac surgery in 715 admissions (97.9%). The duration of milrinone treatment varied from 3 to 64.4 days (≥7 days in 149 admissions). Ejection fraction and fractional shortening of the left ventricle improved in patients receiving milrinone after cardiac surgery. Dose reduction of milrinone due to hypotension occurred in only 4 admissions (0.5%). Although diverse arrhythmias occurred in 75 admissions (10.3%), modification of milrinone infusion to manage arrhythmia occurred in only 3 admissions (0.4%). Multivariate analysis indicated that the development of arrhythmia was not influenced by the pattern of milrinone use. CONCLUSION: Milrinone was generally administered for ≥3 days in children with heart diseases. The use of milrinone for ≥3 days was effective in preventing low cardiac output after cardiac surgery when combined with other inotropes, suggesting that milrinone could be safely employed in pediatric patients with heart diseases.

Macrophage glucose-6-phosphate dehydrogenase stimulates proinflammatory responses with oxidative stress.

Glucose-6-phosphate dehydrogenase (G6PD) is a key enzyme that regulates cellular redox potential. In this study, we demonstrate that macrophage G6PD plays an important role in the modulation of proinflammatory responses and oxidative stress. The G6PD levels in macrophages in the adipose tissue of obese animals were elevated, and G6PD mRNA levels positively correlated with those of proinflammatory genes. Lipopolysaccharide (LPS) and free fatty acids, which initiate proinflammatory signals, stimulated macrophage G6PD. Overexpression of macrophage G6PD potentiated the expression of proinflammatory and pro-oxidative genes responsible for the aggravation of insulin sensitivity in adipocytes. In contrast, when macrophage G6PD was inhibited or suppressed via chemical inhibitors or small interfering RNA (siRNA), respectively, basal and LPS-induced proinflammatory gene expression was attenuated. Furthermore, macrophage G6PD increased activation of the p38 mitogen-activated protein kinase (MAPK) and NF-κB pathways, which may lead to a vicious cycle of oxidative stress and proinflammatory cascade. Together, these data suggest that an abnormal increase of G6PD in macrophages promotes oxidative stress and inflammatory responses in the adipose tissue of obese animals.

An unusual case of left ventricular free wall rupture caused by a silent myocardial infarction.

Left ventricular free wall rupture (LVFWR) is a serious complication of myocardial infarction. It presents with a very high mortality rate and can be rescued by accurate diagnosis and emergency surgery. LVFWR can occur with sudden overt clinical symptoms or present insidiously. This report highlights the case of a man with no prior history of coronary artery disease, who presented with LVFWR and pericardial effusion that evolved to severe bacterial pericarditis.

G6PD up-regulation promotes pancreatic beta-cell dysfunction.

Increased reactive oxygen species (ROS) induce pancreatic ß-cell dysfunction during progressive type 2 diabetes. Glucose-6-phosphate dehydrogenase (G6PD) is a reduced nicotinamide adenine dinucleotide phosphate-producing enzyme that plays a key role in cellular reduction/oxidation regulation. We have investigated whether variations in G6PD contribute to ß-cell dysfunction through regulation of ROS accumulation and ß-cell gene expression. When the level of G6PD expression in pancreatic islets was examined in several diabetic animal models, such as db/db mice and OLEFT rats, G6PD expression was evidently up-regulated in pancreatic islets in diabetic animals. To investigate the effect of G6PD on ß-cell dysfunction, we assessed the levels of cellular ROS, glucose-stimulated insulin secretion and ß-cell apoptosis in G6PD-overexpressing pancreatic ß-cells. In INS-1 cells, G6PD overexpression augmented ROS accumulation associated with increased expression of prooxidative enzymes, such as inducible nitric oxide synthase and reduced nicotinamide adenine dinucleotide phosphate oxidase. G6PD up-regulation also caused decrease in glucose-stimulated insulin secretion in INS-1 cells and primary pancreatic islets. Moreover, elevated G6PD expression led to ß-cell apoptosis, concomitant with the increase in proapoptotic gene expression. On the contrary, suppression of G6PD with small interference RNA attenuated palmitate-induced ß-cell apoptosis. Together, these data suggest that up-regulation of G6PD in pancreatic ß-cells would induce ß-cell dysregulation through ROS accumulation in the development of type 2 diabetes.

La-related protein 4 binds poly(A), interacts with the poly(A)-binding protein MLLE domain via a variant PAM2w motif, and can promote mRNA stability.

The conserved RNA binding protein La recognizes UUU-3'OH on its small nuclear RNA ligands and stabilizes them against 3'-end-mediated decay. We report that newly described La-related protein 4 (LARP4) is a factor that can bind poly(A) RNA and interact with poly(A) binding protein (PABP). Yeast two-hybrid analysis and reciprocal immunoprecipitations (IPs) from HeLa cells revealed that LARP4 interacts with RACK1, a 40S ribosome- and mRNA-associated protein. LARP4 cosediments with 40S ribosome subunits and polyribosomes, and its knockdown decreases translation. Mutagenesis of the RNA binding or PABP interaction motifs decrease LARP4 association with polysomes. Several translation and mRNA metabolism-related proteins use a PAM2 sequence containing a critical invariant phenylalanine to make direct contact with the MLLE domain of PABP, and their competition for the MLLE is thought to regulate mRNA homeostasis. Unlike all ∼150 previously analyzed PAM2 sequences, LARP4 contains a variant PAM2 (PAM2w) with tryptophan in place of the phenylalanine. Binding and nuclear magnetic resonance (NMR) studies have shown that a peptide representing LARP4 PAM2w interacts with the MLLE of PABP within the affinity range measured for other PAM2 motif peptides. A cocrystal of PABC bound to LARP4 PAM2w shows tryptophan in the pocket in PABC-MLLE otherwise occupied by phenylalanine. We present evidence that LARP4 expression stimulates luciferase reporter activity by promoting mRNA stability, as shown by mRNA decay analysis of luciferase and cellular mRNAs. We propose that LARP4 activity is integrated with other PAM2 protein activities by PABP as part of mRNA homeostasis.

Carbonyl reductase 1 protects pancreatic ß-cells against oxidative stress-induced apoptosis in glucotoxicity and glucolipotoxicity.

Carbonyl reductase 1 (CBR1) plays an important role in the detoxification of reactive lipid aldehydes. Oxidative stress has been implicated in the pathogenesis of pancreatic ß-cell failure. However, the functional role of CBR1 in pancreatic ß-cell failure has not been studied yet. Therefore, we investigated the role of CBR1 in pancreatic ß-cell failure under glucotoxic and glucolipotoxic conditions. Under both conditions, knockdown of CBR1 by specific siRNA increased ß-cell apoptosis, expression of lipogenic enzymes (such as ACC, FAS, and ABCA1), intracellular lipid accumulation, oxidative stress, ER stress, and nuclear SREBP1c, but decreased glucose-stimulated insulin secretion. In contrast, overexpression of CBR1 showed the opposite effects. The antioxidants N-acetyl-l-cysteine and Tiron, as well as the FAS inhibitor cerulenin, reversed the effects of CBR1 knockdown. Interestingly, the expression level and enzyme activity of CBR1 were significantly decreased in pancreatic islets of db/db mice, compared with those of wild-type mice. In conclusion, CBR1 protects pancreatic ß-cells against oxidative stress and promotes their survival in glucotoxicity and glucolipotoxicity.

A nonthiazolidinedione peroxisome proliferator-activated receptor α/γ dual agonist CG301360 alleviates insulin resistance and lipid dysregulation in db/db mice.

Activation of peroxisome proliferator-activated receptors (PPARs) have been implicated in the treatment of metabolic disorders with different mechanisms; PPARα agonists promote fatty acid oxidation and reduce hyperlipidemia, whereas PPARγ agonists regulate lipid redistribution from visceral fat to subcutaneous fat and enhance insulin sensitivity. To achieve combined benefits from activated PPARs on lipid metabolism and insulin sensitivity, a number of PPARα/γ dual agonists have been developed. However, several adverse effects such as weight gain and organ failure of PPARα/γ dual agonists have been reported. By use of virtual ligand screening, we identified and characterized a novel PPARα/γ dual agonist, (R)-1-(4-(2-(5-methyl-2-p-tolyloxazol-4-yl)ethoxy)benzyl)piperidine-2-carboxylic acid (CG301360), exhibiting the improvement in insulin sensitivity and lipid metabolism. CG301360 selectively stimulated transcriptional activities of PPARα and PPARγ and induced expression of their target genes in a PPARα- and PPARγ-dependent manner. In cultured cells, CG301360 enhanced fatty acid oxidation and glucose uptake and it reduced pro-inflammatory gene expression. In db/db mice, CG301360 also restored insulin sensitivity and lipid homeostasis. Collectively, these data suggest that CG301360 would be a novel PPARα/γ agonist, which might be a potential lead compound to develop against insulin resistance and hyperlipidemia.