Search

Obesity, a chronic disease, significantly increases the risk of various diseases, including diabetes, cardiovascular diseases, and cancers. Exercise is crucial for weight management not only through energy expenditure by muscle activity but also through stimulating the secretion of myokines, which affect various tissues. Irisin, derived from the proteolytic processing of fibronectin type III domain-containing protein 5 (Fndc5), is a well-studied myokine with beneficial effects on metabolism. This study explored the feasibility of adeno-associated virus (AAV)-mediated Fndc5 gene therapy to treat obesity in a mouse model using the AAV-DIO system to express Fndc5 specifically in skeletal muscle, and investigated its anti-obesity effect. Although Fndc5 was specifically expressed in the muscle, no significant impact on body weight under normal chow or high-fat diets was observed, and no change in thermogenic gene expression in inguinal white adipose tissue was detected. Notably, Fndc5 transduction did affect bone metabolism, consistent with previous reports. These findings suggest that AAV-mediated Fndc5 gene therapy may not be an efficient strategy for obesity, contrary to our expectations. Further research is needed to elucidate the complex mechanisms involved in irisin's role in obesity and related disorders. • AAV-DIO system was used to transduce irisin specifically in skeletal muscles of mice. • Muscle-specific AAV-Fndc5 gene delivery was not effective for anti-obesity effect. • Muscle-specific Fndc5 transduction affected bone remodeling in mice. [ABSTRACT FROM AUTHOR]

Delta age is a biomarker of brain aging that captures differences between the chronological age and the predicted biological brain age. Using multimodal data of brain MRI, genomics, and blood-based biomarkers and metabolomics in UK Biobank, this study investigates an explainable and causal basis of high delta age. A visual saliency map of brain regions showed that lower volumes in the fornix and the lower part of the thalamus are key predictors of high delta age. Genome-wide association analysis of the delta age using the SNP array data identified associated variants in gene regions such as KLF3-AS1 and STX1. GWAS was also performed on the volumes in the fornix and the lower part of the thalamus, showing a high genetic correlation with delta age, indicating that they share a genetic basis. Mendelian randomization (MR) for all metabolomic biomarkers and blood-related phenotypes showed that immune-related phenotypes have a causal impact on increasing delta age. Our analysis revealed regions in the brain that are susceptible to the aging process and provided evidence of the causal and genetic connections between immune responses and brain aging. [ABSTRACT FROM AUTHOR]

Structural health monitoring (SHM) techniques often require a large number of sensors to evaluate and monitor the structural health. In this paper, we propose a deep neural network (DNN)-based SHM method for accurate crack detection and localization in real time using a small number of strain gauge sensors and confirm its feasibility based on experimental data. The proposed method combines a DNN model with principal component analysis (PCA) to predict the strain field based on the local strains measured by strain gauge sensors located rather sparsely. We demonstrate the potential of the proposed technique via a cyclic 4-point bending test performed on a composite material specimen without cracks and seven specimens with different lengths of cracks. A dataset containing local strains measured with 12 strain gauge sensors and strain field measured with a digital image correlation (DIC) device was prepared. The strain field dataset from DIC is converted to a smaller dimension latent space with a few eigen basis via PCA, and a DNN model is trained to predict principal component values of each image with 12 strain gauge sensor measurements as input. The proposed method turns out to accurately predict the strain field for all specimens considered in the study. [ABSTRACT FROM AUTHOR]

Klotho, an anti-aging protein, has gained attention for its protective effects against various diseases, including metabolic disorders, through recombinant Klotho administration. However, the potential of Klotho as a target for gene therapy requires further exploration, as it remains relatively understudied in the context of metabolic disorders. In this study, we demonstrate that AAV-full length(FL)-Klotho administration induces weight loss in mice and provides protection against high-fat diet (HFD)-induced obesity and hepatic steatosis, concurrently reducing the weights of white adipose tissue and liver. AAV-FL-Klotho administration also enhanced thermogenic gene expression in brown adipose tissue (BAT) and improved the morphology of interscapular BAT. The weight loss effect of AAV-FL-Klotho was found to be, at least in part, mediated by UCP1-dependent thermogenesis in brown adipocytes, potentially influenced by hepatokines secreted from AAV-FL-Klotho-transduced hepatocytes. These findings suggest that AAV-FL-Klotho is an attractive candidate for gene therapy to combat obesity. Nevertheless, unbiased experiments have also revealed disturbances in lipid metabolism due to AAV-FL-Klotho, as evidenced by the emergence of lipomas and increased expression of hepatic lipogenic proteins. • This study highlights the potential of AAV-FL-Klotho as an effective gene therapy for combating obesity. • The weight loss effects of AAV-FL-Klotho are mediated by UCP1-dependent thermogenesis and the secretion of hepatokines. • The disturbance of lipid metabolism underscores the need for further investigation. [ABSTRACT FROM AUTHOR]

Desertification and desert sandstorms caused by the worsening global warming pose increasing risks to human health. In particular, Asian sand dust (ASD) exposure has been related to an increase in mortality and hospital admissions for respiratory diseases. In this study, we investigated the effects of ASD on metabolic tissues in comparison to diesel particulate matter (DPM) that is known to cause adverse health effects. We found that larger lipid droplets were accumulated in the brown adipose tissues (BAT) of ASD-administered but not DPM-administered mice. Thermogenic gene expression was decreased in these mice as well. When ASD-administered mice were exposed to the cold, they failed to maintain their body temperature, suggesting that the ASD administration had led to impairments in cold-induced adaptive thermogenesis. However, impaired thermogenesis was not observed in DPM-administered mice. Furthermore, mice fed a high-fat diet that were chronically administered ASD demonstrated unexplained weight loss, indicating that chronic administration of ASD could be lethal in obese mice. We further identified that ASD-induced lung inflammation was not exacerbated in uncoupling protein 1 knockout mice, whose thermogenic capacity is impaired. Collectively, ASD exposure can impair cold-induced adaptive thermogenic responses in mice and increase the risk of mortality in obese mice. [Display omitted] • Asian sand dust (ASD) exposure disrupts the maintenance of normal body temperature of healthy mice. • ASD-administered mice become sensitive to cold due to its impaired thermogenic capacity in the brown adipose tissues. • Loss of heat producing uncoupling protein-1 does not exacerbate the ASD-induced pulmonary inflammation. • Chronic exposure to ASD leads to unexplained weight loss and high serum triglyceride in high-fat diet-induced obese mice. [ABSTRACT FROM AUTHOR]

• Fish community can be utilized as an effective indicator for the river ecosystem assessment. • We present an improved model for assessment of the rehabilitation potential index (RPI) of fish habitats. • The RPI is calculated by integrating the habitat suitability index (HSI), niche breadth (NB), and niche overlap (NO). • The data of fish abundance and 12 habitat environmental factors are used for the calculation of HSI, NB, and NO. • Improved model can be used to plan and assess the river ecosystem restoration and water quality improvement projects. A simple model that can assess the river rehabilitation using rehabilitation potential index (RPI) of fish habitat has been developed. This model calculates the RPI using three indicators: the habitat suitability index (HSI), niche breadth (NB), and niche overlap (NO). These indicators were estimated by using environmental factors that affect fish habitat in the river and then RPI was obtained by combining the indicators. However, the model showed some limitations. For example, the representative NO was obtained by summing each NO, which does not reflect the difference of the number of fish species in rivers. This study improved the estimation method of NO by using the averaged NO that can consider different kinds of species in each river. In addition, the previous study used standardization method for making three indicator values in the range of 0 to 1. However, the standardized indicators can distort the relative size when we compare with the original data. In this study, we have selected alternative methods to calculate indicators, eliminating the need for standardization. Along with these improvements, this study developed a new RPI estimation model by reviewing various methods and selecting the proper ones. The RPIs of the two models were estimated using fish abundance and habitat environmental factors from 57 sites in Han river, Geum river, and Nakdong river in Korea. We compared the results of the existing model with the new model using root mean square error (RMSE) and mean absolute deviation (MAD). The new model showed the reduced uncertainty and enhanced applicability in comparison to the previous model. [ABSTRACT FROM AUTHOR]

The interest in renewable energy to replace fossil fuel is increasing as the problem caused by climate change has become more severe. In this study, small hydropower (SHP) was evaluated as a resource with high development value because of its high energy density compared to other renewable energy sources. SHP may be an attractive and sustainable power generation environmental perspective because of its potential to be found in small rivers and streams. The power generation potential could be estimated based on the discharge in the river basin. Since the river discharge depends on the climate conditions, the hydropower generation potential changes sensitively according to climate variability. Therefore, it is necessary to analyze the SHP potential in consideration of future climate change. In this study, the future prospect of SHP potential is simulated for the period of 2021 to 2100 considering the climate change in three hydropower plants of Deoksong, Hanseok, and Socheon stations, Korea. The results show that SHP potential for the near future (2021 to 2040) shows a tendency to be increased, and the highest increase is 23.4% at the Deoksong SPH plant. Through the result of future prospect, we have shown that hydroelectric power generation capacity or SHP potential will be increased in the future. Therefore, we believe that it is necessary to revitalize the development of SHP to expand the use of renewable energy. In addition, a methodology presented in this study could be used for the future prospect of the SHP potential. [ABSTRACT FROM AUTHOR]

Increasing the thickness of electrodes of lithium-ion batteries (LIBs) is an effective method for improving the volumetric energy density by reducing the inactive materials (e.g., current collector and separator) in LIBs. However, the thickening of conventional electrodes results in poor capacity due to inefficient transport of Li ions through the irregular microstructure of the electrode. To solve this problem, herein, a new three-dimensional (3D) LiCoO 2 (LCO) cathode with periodically aligned microchannels is presented to improve the volumetric energy density of LIBs. The sub-millimeter-thick 3D LCO is fabricated successfully by the ceramics process, which includes lamination of LCO/graphite sheets followed by co-sintering. The 3D LCO demonstrates an excellent areal capacity and rate capability at high rates (31 and 12.1 mAh cm−2 at 0.1 and 1 C, respectively) because of the constant intervals of the microchannels and a low tortuosity value of 1. Moreover, the electrode density of the 3D LCO is similar to that of a conventional LCO, which enables the improvement of the volumetric energy density. A 3D LCO-Li cell achieves a volumetric energy density of up to 1.8 kW h L−1, which is 50% higher than that of a conventional LCO-Li cell. Image 1 • Developed new 3D LiCoO 2 (LCO) cathodes by ceramics process. • 3D LCO cathode microchannels have constant intervals and a minimum tortuosity of 1. • 3D LCO cathodes show an improved areal capacity and higher rate capability. • High volumetric energy density is achieved using 3D LCO-Li metal battery. [ABSTRACT FROM AUTHOR]