Abstract Liraglutide (LRG), one agonist of glucagon-like peptide-1, has multiple lipid-lowering effects in type 2 diabetes mellitus, however, studies on the role of LRG in saturated fatty acid-induced bone loss are limited. Therefore, our aim was to investigate whether LRG reduces palmitate (PA)-induced apoptosis and whether the mechanism involves PKA/β-catenin/Bcl-2/Bax in osteoblastic MC3T3-E1 cells. MC3T3-E1 cells were treated with different concentrations of PA, LRG, or pretreated with Exendin 9–39 and H89, cell viability, intracellular reactive oxygen species (ROS) and cAMP levels, apoptosis and the expression of protein kinase A (PKA), β-catenin, cleaved-Capase 3, Bcl2-Associated X Protein (Bax) and B-cell lymphoma-2 (Bcl-2) along with expression of Osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) were evaluated. PA treatment inhibited cell proliferation and cAMP levels, elevated intracellular ROS levels and promoted apoptosis, increased protein expressions of RANKL, Bax and Cleaved-Caspase3, meanwhile decreased protein expression of OPG and Bcl-2 in a dose-dependent manner. LRG inverted PA-induced apoptosis, increased cAMP levels, promoted expression of p-PKA, p-β-catenin and reversed these gene expression via increasing GLP1R expression. Pretreatment of the cells with Exendin 9–39 and H89 partially eradicated the protective effect of LRG on PA-induced apoptosis. Therefore, these findings indicated that LRG attenuates PA-induced apoptosis possibly by GLP1R-mediated PKA/β-catenin/Bcl-2/Bax pathway in MC3T3-L1 cells. Our results point to LRG as a new strategy to attenuate bone loss associated with high fat diet beyond its lipid-lowering actions.
The aim of this study was to evaluate the predictive value of urinary neutrophil gelatinase-associated lipid (uNGAL) for the prediction of sepsis-associated acute kidney injury (SA-AKI).From September to December 2012, 110 patients were prospectively enrolled from the intensive care units (ICUs) of 3 general hospitals. After being admitted to the ICU, the patients were continuously observed for 72 hours. According to the Kidney Disease Improving Global Outcomes (KDIGO) criteria for the diagnosis of acute kidney injury (AKI), the patients were divided into the AKI group (33 patients) and non-AKI group (77 patients). Per the sepsis diagnostic criteria, the patients were classified as septic (79 patients) and non-septic (31 patients). Serum creatinine and uNGAL of the patients were analyzed daily. The difference in uNGAL in septic and non-septic patients, patients with and without AKI, and septic patients with with and without AKI were compared. In addition, the difference in serum creatinine and uNGAL in patients with and without AKI were recorded and compared, and the sensitivity and specificity of uNGAL and sCr for the diagnosis of AKI in the ICU patients were evaluated using the receiver operating characteristic (ROC) curve.uNGAL levels were all significantly different in septic and non-septic patients (P = .001, P = .028, P = .010, respectively), patients with and without AKI (P = .001, P = .042, P = .001, respectively), septic patients with AKI and septic patients without AKI (P = .003, P = .012, P = .001, respectively) at 24, 48 and 72 hours after being admitted to the ICU, while the difference in sCr was not significant (P = .169) after 24 hours. The area under the ROC curve of uNGAL and sCr in patients admitted to the ICU at 24 hours were 0.828 (95% CI, 0.742 to 0.914) and 0.583 (95% CI, 0.471 to 0.695), respectively. The cutoff value of uNGAL was 170 ng/mL in patients admitted to the ICU at 24 hours, and the sensitivity and specificity were 0.778 and 0.784, respectively. The sensitivity of uNGAL was superior sCr.uNGAL has relatively high sensitivity and specificity in predicting the occurrence of AKI in septic patients, which is superior to sCr and has certain clinical early diagnostic value. uNGAL could be used as an indicator for early diagnosis of AKI in septic patients in the ICU.
The aim of this study was to evaluate the effects of a modified Xiaohua Funing decoction (Xfd) on acute liver failure (ALF) and determine whether the protective mechanisms are related to alterations in the gut microbiota.An animal model of ALF was induced by intraperitoneal injection of D-galactosamine (D-Gal, 0.5 g/kg) and lipopolysaccharide (LPS, 100 μg/kg). Male BALB/c mice were randomly divided into the following 4 groups: the control group (saline, Con), model group (D-Gal/LPS, Mod), silymarin pretreatment group (200 mg/kg, Sil), and modified Xfd pretreatment group (650 mg/kg, Xfd). The Sil and Xfd groups received the respective intervention orally for 14 days and 2 h before D-Gal/LPS treatment. The liver injury markers included alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels and liver histology. 16S rRNA gene sequencing was performed to assess the effects on the caecum content.D-Gal/LPS treatment caused severe ALF, illustrating that the ALF model was successfully established. The administration of Sil and Xfd greatly reduced the serum ALT and AST levels and improved the pathological signs of liver injury. However, no significant difference was found between the two groups. In contrast to the Mod group, the Sil and Xfd groups showed a shift toward the Con group in terms of the gut microbiota structure. The abundances of Firmicutes and Bacteroidetes and the Bacteroidetes/Firmicutes ratio in the Mod group significantly differed from those in the Con group. The Sil and Xfd groups showed restoration of the disordered microbiota. Significantly increased relative abundances of Lachnospiraceae_NK4A136_group and Candidatus_Saccharimonas and a markedly decreased Muribaculaceae abundance were found in the Sil and Xfd mice compared with those in the Mod mice (P < 0.01, P < 0.05). Interestingly, a negative correlation was observed between the abundances of the gut microbiota constituents, specifically Clostridia_UCG-014, and ALT and AST levels.In summary, our results indicate that Xfd may protect the liver and modify the gut microbiota in ALF mice.
Macrovascular disease is tightly associated with obesity-induced metabolic syndrome. Sitagliptin (SIT), an orally stable selective inhibitor of Dipeptidyl peptidase-4 (DPP-4), has protective effects on endothelium. However, the mechanisms enabling SIT to exhibit resistance to diet-induced obesity (DIO) related with reactive oxygen species (ROS) and endoplasmic reticulum (ER) stress in the aorta and endothelial cells have not been reported yet. Therefore, the present study was conducted to determine if SIT exerts protective role in the thoracic aortas isolated from the high-fat diet (HFD)-treated rats and palmitate (PA)-treated endothelial cells by alleviating ROS and ER stress. Male Sprague Dawley rats were randomly divided into standard chow diet (SCD), HFD and HFD plus sitagliptin administration (HFD + SIT) groups. The rats of latter two groups were given HFD fodder for 12 weeks, then the HFD + SIT rats were treated with SIT (10 mg/kg/d) by intragastric administration for another 8 weeks. The body mass, vascular tension, serum oxidative stress indices and inflammatory parameters, pathological changes, protein expression of endothelial nitric oxide synthase (eNOS), the genes associated with ER stress and apoptosis in the thoracic aorta were measured. Furthermore, cell proliferation, ROS and the protein expression associated with ER stress (especially CHOP) and apoptosis were assessed in human umbilical vein endothelial cells (HUVECs) incubated with SIT and PA. Compared to the SCD rats, the HFD rats had higher serum lipid levels, decreased vascular tension, increased inflammation, oxidative and ER stress, and apoptosis of endothelial cells. PA promoted ROS generation, ER stress and apoptosis, inhibited cell proliferation in HUVECs. SIT treatment obviously ameliorated apoptosis via alleviating ROS and ER stress in the thoracic aortas isolated from HFD-fed rats and PA-treated HUVECs. The results suggest that SIT improved endothelial function via promoting cell proliferation and alleviating ROS-ER stress-CHOP pathway both in vivo and in vitro .
Fenofibrate is widely used in clinical practice, but its influence on chronic endoplasmic reticulum (ER) stress induced by feeding a high-calorie and high-cholesterol diet (HCD) has still not been studied. We thus investigated its effects on the liver of the nonalcoholic fatty liver disease (NAFLD) mouse model. Male C57BL/6 mice fed an HCD for 3 months were treated with fenofibrate (HCD + FF, 40 mg/kg, once daily) via gavage for 4 weeks. Insulin sensitivity, serum lipid and inflammatory cytokines were measured. Liver tissues were procured for histological examination as well as analysis of hepatic triglyceride levels, distribution of inflammatory cytokines and genes involved in ER stress. Our results showed that chronic feeding of an HCD successfully induced an NAFLD model accompanied by inflammatory activation, apoptosis and severe ER stress in the liver. Fenofibrate administration significantly improved symptoms of NAFLD and decreased apoptosis, expression of inflammatory cytokines and genes involved in ER stress, such as inositol-requiring enzyme 1α (IRE1α), X-box binding protein 1 (XBP1) and JNK phosphorylation. Thus, our study suggests that fenofibrate protected against inflammatory injury and apoptosis, maybe alleviating ER stress through the IRE1α-XBP1-JNK pathway in the liver of NAFLD mice.
This paper proposes a boundary position optimization method for large thin-walled component submodel based on the simulated annealing algorithm, aiming to effectively solve the problem of low accuracy in simulating large components. The submodel method can reduce the solution scale and improve the solution accuracy, and the key lies in the selection of the boundary position of the submodel. Therefore, this paper transforms the boundary problem into an optimization mathematical model and uses the simulated annealing algorithm to find the boundary position with the minimum mean stress. The simulation results show that the correlation coefficient between the optimized global model and the submodel boundary stress can reach 0.98, which proves that this method can effectively improve the accuracy of submodel boundary data transfer and provides a new approach for the simulation analysis of large thin-walled components.
This study was initiated to determine the possible antidiabetic effects of total flavonoids of Litsea Coreana leve (TFLC), an alcohol extract from the dried leaves of Litsea Coreana leve, on type 2 diabetic rats. Male Sprague-Dawley rats ( n = 40, 160–180 g) were divided into two groups and fed with normal chow diet (Normal Control group) or high-fat diet (HFD) for a period of 4 weeks. After 4 weeks of dietary manipulation, the HFD-fed rats were injected with 30 mg/kg streptozocin (STZ) to induce diabetes 72 hours after STZ injection. These diabetic rats were randomly divided into 3 groups ( n = 10): Diabetic Control group, Diabetic + TFLC group and Diabetic + PIO group. Diabetic + TFLC group and Diabetic + PIO group were orally administered with 400 mg/kg TFLC or 10 mg/kg pioglitazone (all suspended in 0.5% CMC-Na) respectively for 6 weeks. All rats were examined for body weight, serum and hepatic biochemical indices, content of malondialdehyde (MDA), activities of superoxide dismutase (SOD) and pathological changes in liver and pancreas, as well as protein tyrosine phosphatase 1B (PTP1B) expression in liver. The diabetic rats became obese, insulin resistant, hyperglycemic and hyperlipidemic. Treatment with TFLC showed a significant increase in insulin sensitivity, serum HDL-C level and SOD activities, meanwhile marked decrease in body weight, serum FFA, TC, TG, LDL-C, CRP, MDA content. TFLC also attenuated pathologic alterations in liver and pancreatic islet. Furthermore, TFLC was found to decrease the expression of PTP1B in diabetic rat liver. These results suggested that TFLC could ameliorate hyperglycemia, hyperlipoidemia, inflammation and oxidation stress, as well as insulin resistance of type 2 diabetic rats.
To evaluate the prevalence of type 2 diabetes mellitus (T2DM) with chronic kidney disease (DM-CKD) and identify the associated factors in patients attending primary hospitals in Anhui Province, China.A multi-stage sampling method was used to collect the demographic information, general clinical data, and details of the kidney disease of patients in 2019 through a questionnaire survey, physical examination, and laboratory examination.A total of 1067 patients with T2DM were studied, of whom 345 had chronic kidney disease (CKD; 32.33%); 18.8%, 12.2%, 58.0%, 9.9% and 1.2% of the participants had stages 1 to 5 CKD. Fifty-point-three percent of the participants were female and they were 59 ± 11.3 years old. Multivariate regression analysis revealed that age, systolic blood pressure, the duration of diabetes, hyperlipidaemia, and smoking were associated with DM-CKD. The duration of diabetes was positively associated with body mass index, 2-hour postprandial glucose, fasting blood glucose concentration, glycosylated haemoglobin, total cholesterol concentration and triglyceride concentration.The incidence of DM-CKD is relatively high in primary hospitals in Anhui Province. Appropriate preventive and therapeutic measures should be instituted according to the age, the duration of diabetes, sex, hypertension, smoking habits, and lipidaemia of patients.