Stand biomass models can be used as basic decision-making tools in forest management planning. The Moso bamboo (Phyllostachys pubescens) forest, a major forest system in tropical and subtropical regions, represents a substantial carbon sink, slowing down the rise of greenhouse gas concentrations in the earth's atmosphere. Bamboo stand biomass models are important for the assessment of the contribution of carbon to the terrestrial ecosystem. We constructed a stand biomass model for Moso bamboo using destructively sampled data from 45 sample plots that were located across the Yixing state-owned farm in Jiangsu Province, China. Among several bamboo stand variables used as predictors in the stand biomass models, mean diameter at breast height (MDBH), mean height (MH), and canopy density (CD) of bamboo contributed significantly to the model. To increase the model's accuracy, we introduced the effects of bamboo forest block as a random effect into the model through mixed-effects modeling. The mixed-effects model described a large part of stand biomass variation (R2 = 0.6987), significantly higher than that of the ordinary least squares regression model (R2 = 0.5748). Our results show an increased bamboo stand biomass with increasing MH and CD, confirming our model's biological logic. The proposed stand biomass model may have important management implications; for example, it can be combined with other bamboo models to estimate bamboo canopy biomass, carbon sequestration, and bamboo biomass at different growth stages.
Non-alcoholic fatty liver disease (NAFLD) is a clinical syndrome characterized by hepatocyte steatosis and adipose accumulation with the main lesion in the hepatic lobule, but without a history of excessive alcohol consumption. NAFLD ranges from nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH), and may further accumulate fibrosis leading to cirrhosis. Many studies have found that ginseng can treat NAFLD. (20 R)-Panaxadiol (PD) is a panax ginseng diol type compound, has been proved that can treat the obesity. This study wants to investigate the effect of PD on non-alcoholic liver disease. We used 20 ob/ob mice and 10 C57BL/6 J mice. C57BL/6 J mice as CONTROL group, ob/ob mice were divided into model group and PD group. In PD group, ob/ob mice were treated with PD for eight weeks(10 mg/kg, the CON and OB group was given the same amount of sodium carboxymethyl cellulose), detected the weight, food intake and serum index, observed the HE staining of liver and intestine, performed the 16 S rRNA and untargeted metabolomics analysis used mice feces, and verify the results by detect the expression of TNF-α, MDA and SOD. In vivo results, PD can improve abnormal glucose and lipid metabolism and liver function. In 16 S rRNA result, we found beneficial bacteria Muribaculaceae and Lactobacillus increased; in untargeted metabolomics analysis, inflammatory metabolites prostaglandin (PG) and lipopolysaccharide (LPS) decreased, antioxidant metabolites FAD and lipoic acid increased. Then, we proceeded the association analysis of gut microbiota and metabolites, the result showed gut microbiota have strongly associated with anti-inflammatory and antioxidant metabolites. In addition, PD improves intestinal wall integrity. Meanwhile, the expression of TNF-αãMDA and SOD were detected, it was verified that PD has the effect of antioxidant and anti-inflammation. Our study showed that PD, as an active ingredient of ginseng, can play an anti-inflammatory and antioxidant role by improving intestinal metabolites, thereby preventing and treating non-alcoholic fatty liver disease to a certain extent.
Non-alcoholic Fatty Liver Disease , Mice , Animals , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/metabolism , Antioxidants/pharmacology , Tumor Necrosis Factor-alpha/metabolism , Mice, Inbred C57BL , Liver/metabolism , Obesity/drug therapy , Superoxide Dismutase , Metabolomics , Feces
Height to crown base (HCB) is an important predictor variable for forest growth and yield models and is of great significance for bamboo stem utilization. However, existing HCB models built so far on the hierarchically structured data are for arbor forests, and not applied to bamboo forests. Based on the fitting of data acquired from 38 temporary sample plots of Phyllostachys edulis forests in Yixing, Jiangsu Province, we selected the best HCB model (logistic model) from among six basic models and extended it by integrating predictor variables, which involved evaluating the impact of 13 variables on HCB. Block- and sample plot-level random effects were introduced to the extended model to account for nested data structures through mixed-effects modeling. The results showed that bamboo height, diameter at breast height, total basal area of all bamboo individuals with a diameter larger than that of the subject bamboo, and canopy density contributed significantly more to variation in HCB than other variables did. Introducing two-level random effects resulted in a significant improvement in the accuracy of the model. Different sampling strategies were evaluated for response calibration (model localization), and the optimal strategy was identified. The prediction accuracy of the HCB model was substantially improved, with an increase in the number of bamboo samples in the calibration. Based on our findings, we recommend the use of four randomly selected bamboo individuals per sample to provide a compromise between measurement cost, model use efficiency, and prediction accuracy.
Introduction: Obesity is an important cause of a range of metabolic diseases. However, the complex mechanisms of obesity and its related diseases make some weight loss methods ineffective or have safety issues. Ginseng, a specialty of Jilin Province in China with both edible and medicinal value, contains mainly ginsenosides and other components. In order to study the anti-obesity effect of ginseng, network pharmacology was used to predict and screen the active ingredients, action targets and signaling pathways of ginseng. We found (20R)-panaxadiol (PD) is a more desirable active ingredient due to its high drug-like properties and high bioavailability. Moreover, it is closely related to cAMP pathway which is more important in metabolism regulation. The corresponding pharmacodynamic targets of PD include ADRB2 (the gene encoding the ß2-adrenoceptor receptor). Our study aimed to investigate whether Panaxadiol can promote white adipocyte beigeing and increase thermogenesis through modulating the ß2/cAMP pathway to exert anti-obesity effects. Methods: In vivo, we established high-fat feeding obesity model, genotypically obese mice (ob/ob) model, and administered PD (10 mg/kg). PD treatment in ob/ob mice along with ß2 receptor inhibitor ICI118551. In vitro, differentiated mature 3T3-L1 cells were given palmitate (PA) to induce hypertrophy model along with PD (20 µM). Results: The results of this study demonstrated that PD significantly reduced body weight, improved glucose tolerance and lipid levels in high-fat-induced obese mice and ob/ob mice, and also reduced lipid droplet size in PA-treated hypertrophic adipocytes in vitro. Molecular biology assays confirmed that cAMP response element binding protein (CREB) phosphorylation was increased after PD administration, and the expression of thermogenesis-related proteins UCP1, PRDM16 and mitochondrial biosynthesis-related proteins PGC-1α, TFAM and NRF1 were increased. Molecular docking results showed a low binding energy between ß2 receptors and PD, indicating an affinity between the ß2 receptor and PD. In addition, the ß2 receptor inhibition, reversed the anti-obesity effect of PD on the body weight, lipid droplets, the expression of thermogenesis-related proteins and CREB phosphorylation in ob/ob mice. Discussion: These results suggest that PD may promote the expression of thermogenic proteins through phosphorylation of CREB via ß2 receptor activation, and thus exert anti-obesity effects.
Bamboo crown width (CW) is a reliable index for evaluating growth, yield, health and vitality of bamboo, and light capture ability and carbon fixation efficiency of bamboo forests. Based on statistical results produced from fitting the eight basic growth functions using data from 1374 Phyllostachys pubescens in Yixing, Jiangsu Province, China, this study identified the most suitable function (logistic function) to construct a two-level mixed effects (NLME) CW model with the forest block and sample plot-level effects included as random effects in the model. Four methods for selecting sample bamboos per sample plot (largest bamboo, medium-sized bamboo, smallest bamboo, and randomly selected bamboos) and eight sample sizes (1-8 selected bamboos per sample plot) were evaluated to calibrate our NLME CW model. Using diameter at breast height (DBH), height to crown base (HCB), arithmetic mean diameter at breast height (MDBH), and height (H) as predictor variables, the model produced the best fit statistics (Max R2, min RMSE, and TRE). This model was further improved by introducing random effects at two levels. The results showed a positive correlation of CW with HCB and DBH and a negative correlation with H. The smallest two bamboo poles per sample plot used to estimate the random effects of the NLME model provided a satisfactory compromise regarding measurement cost, model efficiency, and prediction accuracy. The presented NLME CW model may guide effective management and carbon estimation of bamboo forests.
Introduction: The quality of new Moso bamboo trees has been found to decrease in the years following strip cutting (SC) events. It is thus essential that we improve our knowledge of nutrient return after strip cutting in Moso bamboo forests to help facilitate sustainable management. Methods: In this investigation the dynamics of nutrient return were monitored in plots with 8 m wide strip cutting (SC), their reserve belts (RB), and a traditionally managed forest (CK) as the control, for 5 years after cutting. Results: The results showed that strip cutting significantly reduced nutrient return (p< 0.05), but as the plots recovered, the nutrient levels also recovered to match those of the control. The high densities in the RB no longer increase nutrient return. Five years after SC there was no significant difference in nitrogen and phosphorus returns among the three treatment plots, but potassium returns in the SC plot were significantly higher than those in the RB (p< 0.05). From 2-5 years after cutting, the litter decomposition rate in the RB was significantly higher than in the SC and CK (p< 0.05). In addition, the decomposition rate in the SC plot was significantly accelerated five years after logging, which suggests that long-term strip cutting management may lead to the restriction of nutrients on the growth and development of new trees. Discussion: The results indicate that nutrients should be added via artificial fertilization in the future.
Strip cutting can effectively reduce the cutting cost of bamboo forests and promote the transformation and upgradation of bamboo forests through mechanization and modernization. Despite the rapid accumulation of Moso bamboo biomass, the dynamics of five years changes in stand characteristics and productivity after cutting remain unclear. This is critical for formulating efficient bamboo forest management measures. In this paper, plots with an 8 m width strip cut (SC) and respective reserved belts (RB) were selected as the research object, and the traditional management forest (CK) as control. The dynamic characteristics of stand, biomass distribution pattern, and productivity change in the different treatment plots were studied for 5 years after cutting. The results showed that cutting increased the number of shoots and new bamboo, and decreased the diameter at breast height, height to crown base, and height of new bamboo (p<0.05). Cutting reduces the productivity of both SC and RB, and allocates more biomass to the bamboo leaves to capture light in SC (p<0.05). Over time, the characteristics of new bamboo in SC reached the level of CK, and the density of standing bamboo, and productivity, were higher than those in CK. However, the number and productivity of new bamboo decreased significantly in the RB (p<0.05), which reflected the density restriction effect of bamboo forest. Further analysis showed that the increase in productivity in SC and CK was mainly from Moso bamboo at II and III "du", which positively correlated with the soil contents of total nitrogen, total phosphorus, and available phosphorus. It was suggested that after three On-year restorations, the SC could reach the level of CK, however it is necessary to density manage RB from the second On-year after cutting.
The aberrant changes of fussion/fission-related proteins can trigger mitochondrial dynamics imbalance, which cause mitochondrial dysfunctions and result insulin resistance (IR). However, the relationship between the inner mitochondrial membrane fusion protein optic atrophy 1 (Opa1) and hepatic IR as well as the specific molecular mechanisms of signal transduction has not been fully elucidated. In this study, we explore whether abnormalities in the Opa1 cause hepatic IR and whether berberine (BBR) can prevent hepatic IR through the SIRT1/Opa1 signalling pathway. High-fat diet (HFD)-fed mice and db/db mice are used as animal models to study hepatic IR in vivo. IR, morphological changes, and mitochondrial injury of the liver are examined to explore the effects of BBR. SIRT1/Opa1 protein expression is determined to confirm whether the signalling pathway is damaged in the model animals and is involved in BBR treatment-mediated mitigation of hepatic IR. A palmitate (PA)-induced hepatocyte IR model is established in HepG2 cells in vitro. Opa1 silencing and SIRT1 overexpression are induced to verify whether Opa1 deficiency causes hepatocyte IR and whether SIRT1 improves this dysfunction. BBR treatment and SIRT1 silencing are employed to confirm that BBR can prevent hepatic IR by activating the SIRT1/Opa1 signalling pathway. Western blot analysis and JC-1 fluorescent staining results show that Opa1 deficiency causes an imbalance in mitochondrial fusion/fission and impairs insulin signalling in HepG2 cells. SIRT1 and BBR overexpression ameliorates PA-induced IR, increases Opa1, and improves mitochondrial function. SIRT1 silencing partly reverses the effects of BBR on HepG2 cells. SIRT1 and Opa1 expressions are downregulated in the animal models. BBR attenuates hepatic IR and enhances SIRT1/Opa1 signalling in db/db mice. In summary, Opa1 silencing-mediated mitochondrial fusion/fission imbalance could lead to hepatocyte IR. BBR may improve hepatic IR by regulating the SIRT1/Opa1 signalling pathway, and thus, it may be used to treat type-2 diabetes.
Berberine , Insulin Resistance , Mice , Animals , Berberine/pharmacology , Berberine/metabolism , Sirtuin 1/genetics , Sirtuin 1/metabolism , Liver/metabolism , Signal Transduction , Mitochondria/metabolism
Obesity is an important cause of diseases such as type 2 diabetes, non-alcoholic fatty liver and atherosclerosis. The use of ingredients extracted from traditional Chinese medicine for weight loss is now receiving more and more attention. Ginseng has been recorded since ancient times for the treatment of diabetes. The (20R)-Panaxadiol (PD) belongs to the ginseng diol type compounds, which are moderately bioavailable and may remain in the intestinal tract for a longer period of time. This study investigated the potential positive effect of PD in ob/ob mice and evaluated its effect against obesity. The ob/ob mice were administered PD for ten weeks. Our study showed that PD could improve obesity, glucose tolerance disorder, as well as gut dysbiosis. Panaxadiol decreased ob/ob mice's Firmicutes/Bacteroidetes (F/B). Furthermore, 16S rRNA gene sequencing of the fecal microbiota suggested that PD changed the composition of the gut microbiota in ob/ob mice and modulated specific bacteria such as lactobacillus, prevotellace and so on. Moreover, PD improved the intestinal wall integrity. In conclusion, our results suggest that (20R)-Panaxadiol, as an active ingredient of the traditional Chinese medicinal herb ginseng, may improve obesity to some extent via improving gut microbiota.
Diabetes Mellitus, Type 2 , Gastrointestinal Microbiome , Panax , Animals , Diabetes Mellitus, Type 2/complications , Diet, High-Fat , Ginsenosides , Mice , Mice, Inbred C57BL , Obesity/etiology , RNA, Ribosomal, 16S/genetics
Osteoarthritis is a common multifactorial chronic disease that occurs in articular cartilage, subchondral bone, and periarticular tissue. The pathogenesis of OA is still unclear. To investigate the differences in serum metabolites between OA and the control group, liquid chromatography/mass spectrometry (LC/MS)-based metabolomics was used. To reveal the pathogenesis of OA, 12 SD male rats were randomly divided into control and OA groups using collagenase to induce OA for modeling, and serum was collected 7 days after modeling for testing. The OA group was distinguished from the control group by principal component analysis and orthogonal partial least squares-discriminant analysis, and six biomarkers were finally identified. These biomarkers were metabolized through tryptophan metabolism, glutamate metabolism, nitrogen metabolism, spermidine metabolism, and fatty acid metabolism pathways. The study identified metabolites that may be altered in OA, suggesting a role in OA through relevant metabolic pathways. Metabolomics, as an important tool for studying disease mechanisms, provides useful information for studying the metabolic mechanisms of OA.
Biomarkers/blood , Cartilage, Articular/metabolism , Metabolomics , Osteoarthritis/blood , Animals , Cartilage, Articular/drug effects , Cartilage, Articular/pathology , Chromatography, Liquid , Collagenases/toxicity , Disease Models, Animal , Fatty Acids/blood , Glutamic Acid/blood , Humans , Mass Spectrometry , Metabolic Networks and Pathways , Metabolome/genetics , Nitrogen/blood , Osteoarthritis/chemically induced , Osteoarthritis/genetics , Osteoarthritis/metabolism , Rats , Spermidine/blood , Tryptophan/blood
Strip clearcutting can significantly reduce the harvesting costs of moso bamboo forests. Although bamboo is characterized by rapid accumulation of biomass, it is still a concern that this management method may reduce long-term productivity. Nutrient cycling has long been considered essential for forests to maintain high primary productivity. However, nutrient cycling of bamboo forests after strip cutting has not been previously reported. We conducted a strip clearcutting experiment and surveyed the litter dynamics for 1 year. We assessed changes in litter nutrients in response to the cutting and calculated the nutrient resorption efficiency and litter decomposition rate to evaluate the effect on nutrient use efficiency and nutrient return. Our results showed that strip cutting had no significant effect on litter production and nutrient return in the moso bamboo forest (p > 0.05). However, annual litter biomass and nutrient return in reserved belts (RB) were significantly higher than those in the control (CK) (p < 0.05). P and K resorption efficiencies in RB were significantly higher than in CK during certain periods of bamboo growth (p < 0.05). We also observed that the annual decay constant of CK was significantly higher than that of plots that were strip clearcut (SC) (p < 0.05). Our results suggest that strip cutting does not affect nutrient use efficiency or storage in the short term.
Excess glucocorticoid (GC) production is known to induce obesity and insulin resistance through increased activation of the glucocorticoid receptor (GR). The molecular mechanism for the non-genomic effects of excessive circulating GC on the insulin-signalling pathway in skeletal muscle is unknown. The plant alkaloid berberine has been shown to attenuate insulin resistance and inhibit gluconeogenesis in type 2 diabetic animals. A highly bioavailable berberine formulation termed Huang-Gui solid dispersion (HGSD), is a preparation of berberine coupled to sodium caprate and this markedly improving berberines bioavailability. Here we examined how HGSD treatment attenuated GR-mediated alteration in PI3K signalling and insulin resistance in diabetic rats, dexamethasone-treated mice and in insulin resistant C2C12 skeletal muscle cells. Blood glucose and skeletal muscle GC levels were increased and insulin signalling impaired in skeletal muscle of type 2 diabetic rats compared to controls. Treatment of these animals with HGSD restored blood glucose and skeletal muscle GC levels to that of controls. Insulin resistant C2C12 skeletal muscle cells exhibited impaired insulin signalling compared to controls and treatment of HGSD and RU486, an antagonist of GR, restored insulin signalling to that of control cells. Administration of dexamethasone to mice increased GR/GRα-associated PI3K and reduced IRS1-associated PI3K, phosphorylated-AKT, and membrane GLUT4 translocation resulting in a higher blood glucose concentration compared to controls. HGSD treatment of these mice improved insulin resistance by reducing the association of GR/GRα with PI3K. Excess GC-induced insulin resistance is mediated by increased association of GR with PI3K and treatment with HGSD attenuates these effects. We hypothesize that HGSD may be a promising candidate drug for the treatment of type 2 diabetes by reducing the association of GR with PI3K in skeletal muscle.
Berberine/therapeutic use , Diabetes Mellitus, Experimental/drug therapy , Insulin Resistance , Phosphatidylinositol 3-Kinase/metabolism , Receptors, Glucocorticoid/metabolism , Animals , Berberine/pharmacology , Cell Line , Dexamethasone , Drug Evaluation, Preclinical , Insulin/metabolism , Male , Mice , Mice, Inbred ICR , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Random Allocation , Rats, Wistar
PURPOSE: Hepatocellular carcinoma (HCC) is one of the most malignant cancers around the world. HCC is less sensitive to conventional cytotoxic agents and easily develops into systemic metastases. However, the molecular mechanisms of the metastasis of HCC are poorly understood and need elucidation. MATERIALS AND METHODS: Transwell system of the chemotherapy-challenged and unchallenged HepG2 cells was established. Adhesion assay and scratch-wound assay were utilized to analyze the adhesion and migration of HepG2 cells. iPLA2 and LOX-5 expression were analyzed by Western blot. LTB4 level was analyzed by ELISA. RESULTS: Chemotherapeutics are traditionally regarded as a way of killing tumor cells; on the other hand, we proved that the chemotherapeutics-induced tumor cell apoptosis can also change the tumor microenvironment by activating the LOX pathway and subsequently release inflammatory factors such as LTB4 which can stimulate the adhesion and migration of the small number of surviving cells. Berberine can reverse the adhesion and migration of HepG2 cells by inhibiting the expression of LOX-5 and reducing the LTB4 production in the tumor microenvironment. CONCLUSION: Our study sheds light on a novel anti-metastasis strategy that the combination of Berberine and chemotherapy may prevent the chemotherapy-induced metastasis in HCC.
Moso bamboo (Phyllostachysheterocycla (Carr.) Mitford cv. Pubescens) is an economically valuable plant in bamboo production areas of southern China, for which the management mode is crucial for improving the comprehensive benefits of bamboo forest stands. In this respect, mixed forested areas of bamboo and broad-leaved tree species can provide sound ecological management of bamboo in forestry operations. To further this goal, an outstanding question is to better understand the spatial distribution of soil bacterial communities in relation to the proportion of mixed in bamboo and broad-leaved forest. We analyzed soil bacterial community diversity and composition along a proportional gradient of 0-40% mixed-ratio (as represented by the width and size of the broad-leaved tree crown over the plot area) of bamboo and broad-leaved forest in Tianbao Yan Nature Reserve using the highthroughputsequencing of the 16S rRNA gene.Specifically, the sampling plots for the mixed proportions were divided according to the percentage of summed projected area of live broadleaf tree crowns. The main broad-leaved species in the five mixed ratio plots are the same. Each plot was 20 m × 20 m in size, and a total of 15 plots were established, three per forest ratio class. From each plot, soil samples were taken at the surface (0-10 cm depth) in December 2017. Our analysis revealed that soil bacterial diversity community structure and dominant flora changed under different mixing ratios of bamboo and broad-leaved trees. In the stand with a mixed ratio of 10-20%, the bacterial diversity index is higher; however, the diversity was lowest in the 20-30% stands. Among the 20-30% forest soil, Acidobacteria (Solibacteria, Solibacteriales, Acidobacteriales) was more abundant than in soils from other mixed-ratio stands.Redundancy analysis showed that mixed forest stand structure, soil pH, organic carbon, total nitrogen, and soil moisture all contributed to shaping the bacterial community structure. Changes in microbial communities were associated with species diversity in tree layers, availability of soil nutrients (SOC and TN), and changes in soil physical properties (MS, pH). Together, these empirical results suggest that different mixing ratios in the bamboo-broad-leaved mixed forest could influence the soil bacterial community structure indirectly, specifically by affecting the soil physical and chemical properties of the forest.
Microbiota/genetics , RNA, Ribosomal, 16S/genetics , Sasa/microbiology , Soil Microbiology , Bacteria/genetics , Bacteria/metabolism , Carbon/metabolism , China/epidemiology , Forests , Humans , Nitrogen/metabolism , Pinus/genetics , Pinus/microbiology , Sasa/genetics , Sasa/growth & development
Glomerular mesangial matrix expansion and cell autophagy are the most important factors in the development of kidney damage under diabetic conditions. The activation of AMPK might be an important treatment target for diabetic nephropathy. Berberine has multiple effects on all types of diabetic complications as an activator of AMPK. However, the poor bioavailability of berberine limits its clinical applications. Huang-Gui Solid Dispersion (HGSD), a new formulation of berberine developed in our lab, has 4-fold greater bioavailability than berberine. However, its therapeutic application and mechanism still need to be explored. In the present study, the effect of HGSD on kidney function in type 2 diabetic rats and db/db mice was investigated. The results demonstrated that HGSD improved kidney function in these two animal models, decreased the glomerular volume and increased autophagy. Meanwhile, AMPK phosphorylation levels and autophagy-related protein expression were significantly increased, and extracellular matrix protein deposition-related protein expression was decreased after treatment. The present study indicated that HGSD protected against diabetic kidney dysfunction by inhibiting glomerular mesangial matrix expansion and activating autophagy. The mechanism of HGSD in the treatment of diabetic nephropathy might be connected to the activation of AMPK phosphorylation.
Autophagy/drug effects , Berberine/pharmacology , Diabetic Nephropathies/drug therapy , Mesangial Cells/drug effects , AMP-Activated Protein Kinases/drug effects , Animals , Berberine/pharmacokinetics , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/complications , Diabetic Nephropathies/pathology , Drug Compounding , Enzyme Activation/drug effects , Extracellular Matrix Proteins/metabolism , Glucose Tolerance Test , Kidney Function Tests , Male , Phosphorylation , Rats , Rats, Wistar
Mitochondrial dynamics, the processes of mitochondrial fusion and fission maintain homeostasis, are precisely regulated by fusion/fission-related proteins, and play an important physiological role in mitochondrial metabolism, quality and function. The aberrant changes of these proteins can trigger mitochondrial dynamics imbalance, which cause mitochondrial dysfunctions and result various disease states. This article focuses on gene knockout technology, and reviews the role and application progress of genes encoding for fusion and fission knockout mice in insulin resistance researches, in order to lay a foundation for future studies on signal transduction mechanism of mitochondrial dynamics imbalance in insulin resistance.
Insulin Resistance , Mitochondrial Dynamics , Animals , Gene Knockout Techniques , Mice , Mitochondria , Mitochondrial Proteins
Bioinspired superhydrophobic substrates have been used in many scientific and technological areas. These substrates can trap atmosphere-linked air pockets at the solid-liquid interface, offering an opportunity to address the oxygen-deficit problem in many reaction systems. Herein, we addressed the oxygen-deficit problem in metal oxide electrochemical deposition by using a triphase electrode possessing an air-liquid-solid joint interface. Oxygen in the interface is directly available from the air phase for sufficient OH- production via oxygen cathodic reaction, thereby offering us a green approach to fabricate two-dimensional mesoporous ZnO nanoarrays over a wide range of current densities. Further, because metal oxides are deposited at the triphase interface, sufficient O2, a natural electron scavenger required in photocatalytic reaction to suppress the recombination of photogenerated electron-hole pairs, can be directly supplied, and we demonstrated their enhanced photocatalytic reaction kinetics in water remediation. The present work highlights a powerful interface-engineering strategy for fabricating metal oxides with unprecedented photocatalytic ability.
Aims: Berberine (BBR) improves beta-cell function in Type 2 diabetes (T2D) because of its anti-apoptotic activity, and our laboratory developed a new preparation named Huang-Gui Solid Dispersion (HGSD) to improve the oral bioavailability of BBR. However, the mechanism by which BBR inhibits beta-cell apoptosis is unclear. We hypothesized that the Group VIA Ca2+-Independent Phospholipase A2 (iPLA2ß)/Cardiolipin(CL)/Opa1 signaling pathway could exert a protective role in T2D by regulating beta-cell apoptosis and that HGSD could inhibit ß-cell apoptosis through iPLA2ß/CL/Opa1 upregulation. Methods: We examined how iPLA2ß and BBR regulated apoptosis and insulin secretion through CL/Opa1 in vivo and in vitro. In in vitro studies, we developed Palmitate(PA)-induced apoptotic cell death model in mouse insulinoma cells (MIN6). iPLA2ß overexpression and silencing technology were used to examine how the iPLA2ß/CL/Opa1 interaction may play an important role in BBR treatment. In in vivo studies, db/db mice were used as a diabetic animal model. The pancreatic islet function and morphology, beta-cell apoptosis and mitochondrial injury were examined to explore the effects of HGSD. The expression of iPLA2ß/CL/Opa1 was measured to explore whether the signaling pathway was damaged in T2D and was involved in HGSD treatment. Results: The overexpression of iPLA2ß and BBR treatment significantly attenuated Palmitate- induced mitochondrial injury and apoptotic death compared with Palmitate-treated MIN6 cell. In addition, iPLA2ß silencing could simultaneously partly abolish the anti-apoptotic effect of BBR and decrease CL/Opa1 signaling in MIN6 cells. Moreover, HGSD treatment significantly decreased beta-cell apoptosis and resulted in the upregulation of iPLA2ß/CL/Opa1 compared to those of the db/db mice. Conclusion: The results indicated that the regulation of iPLA2ß/CL/Opa1 by HGSD may prevent beta-cell apoptosis and may improve islet beta-cell function in Type 2 diabetic mice and in palmitate-treated MIN6 cells.
Apoptosis , Berberine/pharmacology , Cardiolipins/metabolism , Diabetes Mellitus, Type 2/metabolism , GTP Phosphohydrolases/metabolism , Group VI Phospholipases A2/metabolism , Animals , Cell Line , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/drug therapy , Gene Silencing , Glucose Tolerance Test , Insulin/metabolism , Insulin-Secreting Cells/metabolism , Male , Medicine, Chinese Traditional , Membrane Potential, Mitochondrial , Mice , Mice, Inbred C57BL , Mitochondria/metabolism , Palmitates , Signal Transduction
Gaseous reactants play a key role in a wide range of biocatalytic reactions, however reaction kinetics are generally limited by the slow mass transport of gases (typically oxygen) in or through aqueous solutions. Inspired by the morphologies of natural non-wetting surfaces, herein we address this limitation by developing a triphase reaction system possessing a triphase gas-solid-liquid interface. As a proof of concept, we study the kinetics of glucose oxidase (GOx) catalyzed reactions using a triphase system fabricated by layering GOx upon superhydrophobic mesoporous ZnO nanowire arrays through which oxygen, needed for the enzymatic reaction, is supplied directly from the atmosphere to the liquid-solid interface. We find that the enzymatic reaction rate is enhanced by a factor of 30 over that obtained from a conventional diphase system where oxygen is supplied through and from the liquid. The triphase system offers the opportunity to develop high performance bioassay systems, serving as an enabling platform for addressing challenges posed by gas-deficit kinetics.
Glucose Oxidase/chemistry , Nanowires/chemistry , Oxygen/chemistry , Electrochemical Techniques/instrumentation , Electrochemical Techniques/methods , Electrodes , Enzymes, Immobilized/chemistry , Glucose/chemistry , Kinetics , Limit of Detection , Nanopores , Oxidation-Reduction , Porosity , Proof of Concept Study , Zinc Oxide/chemistry
Long, well-separated single crystal TiO2 nanowire (NW) arrays with rapid charge transport properties hold great promise in photoelectrochemical and energy storage devices. Synthesis variations to increase the NWs length generally result in the widening of the NWs and fusion at their roots which, in turn, increases the structural disorder and slows charge transport. As such, well-separated single-crystal TiO2 NW arrays with rapid charge transport properties have been limited to lengths of about 3-4 µm. In this work, by adjusting the HCl/DI-water ratio and adding specific organic ligands to the reaction solution that slow the lateral growth rate we achieve well-separated single-crystal rutile TiO2 NW arrays with a length of â¼10 µm and an aspect ratio of approximately 100. The charge transport is 100 times faster than that of nanoparticle films and remarkably exhibits length-independence, a behavior that can be attributed to the well-separated architecture. The synthesis strategy can be extended to the fabrication of other well-separated metal oxide NW arrays and represents an important tool in achieving high performance photoelectrochemical and electrical energy storage devices.
