High Glucose Research Articles

Extracellular signal-regulated kinase is activated in podocytes from patients with diabetic nephropathy.

In the past few decades, the global prevalence of diabetes has provided us with a warning about future chronic complications. Diabetic nephropathy (DN) is the main cause of end-stage kidney disease. Podocytes in the glomerulus play a critical role in regulating glomerular permeability, and podocyte injury is one of the main causes of DN. Extracellular signal-regulated kinase (ERK) is a member of the mitogen-activated protein kinase family that plays critical roles in intracellular signal transduction. In human patients with DN, phosphorylated ERK (pERK), the active form of ERK, is increased in the glomeruli. However, information on the expression of pERK, specifically in podocytes in DN, is limited. Meanwhile, high glucose induces ERK activation in immortalized podocyte cell lines, suggesting the involvement of podocytic ERK in DN. We performed an immunohistochemical study using Wilms' tumor-1 (WT-1) as a podocyte-specific marker to investigate whether podocytic pERK levels are increased in patients with DN. In the glomeruli of the DN group, we observed remarkable co-staining for WT-1 and pERK. In contrast, the glomeruli of the control group contained only a few pERK-positive podocytes. Statistical analyses revealed that, relative to healthy controls, patients with DN showed significantly increased pERK expression levels in cells that were positive for WT-1 (DN: 51.3 ± 13.1% vs. control: 7.3 ± 1.6%, p = 0.0158, t-test, n = 4 for each group). This suggests that ERK activation in podocytes is involved in the pathogenesis of DN.

High glucose availability alters the proteomic profile of small placental extracellular vesicles and their ability to induce endothelial dysfunction.

High glucose availability alters the proteomic profile of small placental extracellular vesicles and their ability to induce endothelial dysfunction.

Using chondroitin sulfate lithium hydrogel for diabetic bone regeneration via regulation of macrophage polarization

Bone regeneration in a diabetic environment remains a clinical challenge because of the proinflammatory microenvironment and malfunction of osteogenesis. Traditional therapy for bone defects doesn't work out in diabetes. Therefore, we introduced lithium (Li) into chondroitin sulfate (CS) and developed a crosslinked hydrogel composed of gelatin methacryloyl (GelMA) and chondroitin sulfate lithium (CS-Li) which could release Li in a sustained manner. This crosslinked hydrogel has a porous microstructure, excellent biocompatibility, and osteogenesis properties. With the synergetic effects of CS and Li, this crosslinked hydrogel regulates macrophage polarization to anti-inflammatory phenotype in the high glucose microenvironment and alleviates the inhibition of angiogenesis and osteogenesis caused by diabetes both in vitro and in vivo. The relationship between macrophage polarization and the promotion of angiogenesis and osteogenesis in diabetic microenvironments may be attributed to the activation of Glycogen synthase kinase-3β/β-catenin pathways. Overall, significant results in this study present that CS-Li was a potential therapy for bone defects in diabetic patients.

Innovative microfluidic technologies in precision research and therapy development in diabetic neuropathy: a narrative review

Diabetic neuropathy is a prevalent complication of diabetes mellitus and is characterized by progressive nerve damage that results in sensory and motor deficits. Although traditional in vitro models have provided valuable insights, they often lack the complexity needed to fully mimic the pathophysiology of DN. Microfluidic technology offers sophisticated platforms that focus on simulating the neural environment, isolating axons, simulating axonal interactions with Schwann cells, simulating blood–nerve barrier dynamics, and integrating nerve-target tissue interactions to better recapitulate the physiological and pathological conditions of the peripheral nervous system affected by diabetes, potentially revolutionizing DN research. This review explores the application of microfluidic platforms in neurobiology research, focusing on their ability to model key aspects such as axonal degeneration, myelination deficits, blood–nerve barrier dysfunction, and interactions between nerves and target tissues. Microfluidic devices enable precise control over the cellular microenvironment, facilitating studies on how factors such as high glucose levels, oxidative stress, and inflammation contribute to nerve damage in DN. Perspectives on challenges and future directions are discussed, including the need for enhanced biomimicry, standardized experimental protocols, and integration with patient-derived cells for personalized medicine approaches. Overall, microfluidic platforms represent a promising toolset for advancing our understanding of diabetic neuropathy pathogenesis, accelerating the development of therapies, and ultimately alleviating the burden of diabetic neuropathy on patients.

Development of a programmable automated cell culture system to study the lung pathophysiology of Cystic Fibrosis-related diabetes

The study of many diseases is limited by the in vitro systems available. Cystic Fibrosis-Related Diabetes (CFRD), the main co-morbidity of Cystic Fibrosis (CF), is a perfect example. Cells in vivo experience glucose fluctuations after meals. In contrast, cells cultured in vitro are initially exposed to high glucose media. Glucose gets progressively depleted until the next media change days later, which is not physiologically relevant and could negatively impact the results of research studies. To better study the mechanisms driving CFRD pathophysiology, we developed a programmable and automated cell culture system (PACCS) capable of mimicking acute hyperglycemic episodes experienced by CFRD patients after meals. We adapted a commercially available perfusion system and performed 3D modeling to develop this system. Results show that PACCS can be successfully used to culture airway epithelial cells, both immortalized and primary cells. Further, CF cells responded differently to meal-like conditioning when compared to controls, suggesting impaired adaptative responses in CF cells. Overall, PACCS will allow us to better study CFRD pathophysiology, and it could be used for a wide range of other applications.

Neutrophil extracellular traps induced by diabetes aggravate periodontitis by inhibiting janus kinase/signal transducers and activators of transcription signaling in macrophages

Background/purposeDiabetes, which is a systemic disease, increases susceptibility to destructive periodontal diseases, which are characterized by infectious susceptibility, but the potential mechanisms remain unknown. The aim of this study was to investigate the mechanism of high glucose environment promoting the occurrence and development of local periodontal inflammation. Materials and methodsIn this study, the effects of neutrophil extracellular traps (NETs) on macrophage polarization and the mechanism were designed to verify whether this course plays a role in periodontal tissue impairment associated with diabetes. Here, we examined the impact of NETs on macrophages in vitro. NETs were isolated from cultures of neutrophils exposed to hyperglycemia. Mouse models of diabetic periodontitis (DP) and macrophage polarization were developed, and the degrees of NET formation in the periodontal tissue of DP mice were assessed. Furthermore, western blotting was performed to analyze the related mechanisms. ResultsThe results revealed that hyperglycemia induced the formation of NETs, and abundant NET formation led to proinflammatory cytokine secretion by macrophages and low expression of JAK-2 and STAT-3 in vitro and in vivo. NETs regulated macrophage polarization through the JAK/STAT pathway. ConclusionThese results suggest that NETs target proinflammatory cytokine secretion via the JAK/STAT pathway and may play important roles in DP progression and macrophage polarization, which indicates that therapeutically referring to this regulatory pathway might be a promising method for treating diabetes-associated inflammatory diseases.

Thioredoxin Interacting Protein Expressed in Osteoblasts Mediates the Anti-Proliferative Effects of High Glucose and Modulates the Expression of Osteocalcin.

Hyperglycemia is associated with impaired bone health in patients with diabetes mellitus. Although a direct detrimental effect of hyperglycemia on the bone has been previously reported, the specific molecular mediator(s) responsible for the inhibitory effect of high glucose levels on the bone remains unclear. We hypothesized that thioredoxin-interacting protein (Txnip), an essential mediator of oxidative stress, is such a mediator. We cultured MG-63 cells (immortalized human osteoblasts) with normal or high glucose concentrations and transfected them with scrambled or Txnip-specific small interfering RNA (siRNA). High glucose levels increased Txnip expression and reduced MG-63 cell proliferation. The high-glucose level mediated reduction in cell proliferation was prevented in Txnip siRNA-transfected cells. In addition, we demonstrated that silencing Txnip mRNA expression in osteoblasts reduced the expression of the osteocalcin gene. Our results suggest that high glucose levels or silencing of Txnip mRNA expression may induce apoptosis in osteoblasts. Our findings indicate that Txnip is an intracellular mediator of the anti-proliferative effects of extracellular high glucose levels on osteoblasts.

MSU crystallization promotes fibroblast proliferation and renal fibrosis in diabetic nephropathy via the ROS/SHP2/TGFβ pathway

Monosodium urate (MSU) crystallisation deposited in local tissues and organs induce inflammatory reactions, resulting in diseases such as gout. MSU has been recognized as a common and prevalent pathology in various clinical conditions. In this study, we investigated the role of MSU in the pathogenesis of diabetic kidney disease (DKD). We induced renal injury in diabetic kidney disease mice using streptozotocin (STZ) and assessed renal histopathological damage using Masson's trichrome staining and Collagen III immunofluorescence staining. We measured the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and uric acid (UA) using ELISA. Protein expression levels of NLRP3, p-NF-κB, SHP2, p-STAT3, and p-ERK1/2 were analyzed by Western blot. To further investigate the role of MSU in diabetic kidney disease, we conducted in vitro experiments. In our in vivo experiments, we found that compared to the Model group, there was a significant increase in interstitial fibrosis in the kidneys of mice after treatment with MSU, accompanied by elevated levels of MDA, SOD, and UA. Furthermore, the protein expression of NLRP3, p-NF-NB, SHP2, p-STAT3, and p-ERK1/2 was upregulated. In our subsequent studies on mouse fibroblasts (L929 cells), we discovered that high glucose, MSU, and TGF-β could promote the expression of P22, GP91, NLRP3, NF-κB, p-NF-κB, p-SHP2, p-EGFR, p-STAT3, and Collagen-III proteins. Additionally, we found that SHP2 could counteract the upregulation trend induced by MSU on the expression of p-SHP2, p-EGFR, p-STAT3, and Collagen-III proteins, and inhibitors YQ128, NAC, and Cetuximab exhibited similar effects. Furthermore, immunofluorescence results indicated that SHP2 could inhibit the expression of the fibrosis marker α-SMA in L929 cells. These findings suggest that MSU can promote renal fibroblast SHP2 expression, induce oxidative stress, activate the NLRP3/NF-κB pathway, and enhance diabetic kidney disease fibroblast proliferation through the TGFβ/STAT3/ERK1/2 signaling pathway, leading to renal fibrosis.

RANKL/RANK contributes to the pathological process of type 2 diabetes mellitus through TRAF3 activation of NIK

Diabetic osteoporosis is a complication of diabetes mellitus (DM). Denosumab (DMB) is an effective anti-osteoporotic drug functions by inhibiting NF-κB ligand receptor-activating factor (RANKL). Previous study found that osteoprotegerin (OPG) regulated βcell homeostasis through the RNAK/RANKL pathway. The present study aimed to investigate the effect of RANKL/RANK on the pathological process of DM and the underlying mechanism. We used D-glucose-induced RINm5F cells to construct in vitro type 2 diabetes models (T2DM). A high-fat diet combined with intraperitoneal injection of streptozotocin (STZ) was used to establish a T2DM model in SD rats. The apoptosis of β-cells was determined by TdT-mediated dUTP nick-end labeling (TUNEL) analysis. qRT-PCR and western blotting assays were used to explore the mRNA and protein expression of the TRAF3 (Tumor necrosis factor receptor-associated factor)/NIK (NF-κB-inducible kinase) pathway. Furthermore, insulin expression was detected by ELISA and immunohistochemistry assay. The islet morphology was analyzed by H&E. In vivo experiments demonstrated that sRANKL-IN-3 down-regulated insulin secretion levels by significantly ameliorating pancreatic tissue damage and mitigating apoptosis of high glucose induced β-cells. Subsequently, sRANKL-IN-3, acting as an inhibitor of RANKL, mitigated functional decline in β-cells induced by high glucose, mainly manifested by the low expression of PDX-1 (pancreatic duodenal homeobox 1), BETA2 (beta-2 adrenoceptors), INS-1 (insulin 1), and INS-2 (insulin 2). Mechanistic studies revealed that deletion of TRAF3 combined with sRANKL-IN-3 administration reduced the activity of NIK, NF-κB2, and RelB in RINm5F cells. In addition, our study demonstrated that inhibition of either RANKL or TRAF3 had a protective effect on high glucose induced apoptosis. Moreover, the combined action of sRANKL-IN-3 and shTRAF3 had a more pronounced inhibitory effect on high glucose-induced apoptosis. In summary, RANKL/RANK deficiency may attenuate apoptosis of β-cells, a phenomenon associated with the TRAF3/NIK pathway. Therefore, RANKL/RANK could be regarded as a potential therapeutic strategy for DM.

Effect of High Glucose on Embryological Development of Zebrafish, Brachyodanio, Rerio through Wnt Pathway.

Gestational diabetes mellitus (GDM) is a worldwide pregnancy complication. Gestational diabetes can significantly impact fetus development. However, the effects of high glucose on embryological development post-fertilization are yet to be researched. Danio rerio embryos are a great model for studying embryonic development. In this study, the effects on embryological (morphological and genetic) development were examined in the presence of a high-glucose environment that mimics the developing fetus in pregnant women with GDM. Fertilized zebrafish embryos were treated with normal media and high glucose for 5 days from 3 h post-fertilization (hpf) to 96 hpf, respectively, as control and experimental groups. Morphological changes are recorded with microscope images. Hatch rate and heart rate are compared between groups at set time points. RNA-Seq is performed to examine the gene changes in the experimental group. Glucose delayed the zebrafish embryo development by slowing the hatch rate by about 24 h. The brain, heart, and tail started showing smaller morphology in the glucose group compared to the control group at 24 hpf. Heart rate was faster in the glucose group compared to the control group on days 2 and 3 with a statistically significant difference. Among the zebrafish whole genome, the significantly changed genes were 556 upregulated genes and 1118 downregulated genes, respectively, in the high-glucose group. The metabolic and Wnt pathways are altered under high-glucose conditions. These conditions contribute to significant physiological differences that may provide insight into the functionality of post-embryological development.

Effects of nutritional education on metabolic syndrome parameters in a sample of adults in Subotica, Northern Serbia

The aim of this study is to assess the changes in metabolic syndrome parameters among adults after the implementation of nutrition education. The research was conducted as a prospective, longitudinal, quasi-experimental evaluation study from May to December 2022. The research sample included 31 employees at the College of Vocational Studies in Subotica. The study was conducted in three phases: Initial assessment (anthropometric, clinical, biochemical measurements and eating habits), Nutrition educations (onloine and face-to-dace) and Evaluative assessment (six months after the initial assessment). Data analysis included methods of descriptive and comparative statistical analysis. Nutrition education was conducted for 31 participants, but only 18 responded to the evaluative assessment. Two thirds (62%) of the participants were overweight ad had elevated cholesterol levels. Elevated triglyceride values were registered in more than a half of the participants and high blood glucose levels in 13% of participants. More than a third of the participants had three or four risk factors for the development of metabolic syndrome. After nutrition education, distribution of participants according io BMI significantly changed (I—normal: 37%; overveigt: 31%; obese:29%; E—normal:10%; overveigt:29%; obese:19%; p = 0,001). Significant changes in the distribution of total cholesterol levels (I: 5.7 mmol/l; E: 5.4 mmol/l) was determined at the evaluative assessment (p = 0.005). Statistically changes in the distribution of breakfast (p = 0.001) and vegetables (p = 0.013) intake were observed. There were not determined significant changes in other antropometric, clinical and biochemical parameters after nutrition education. Although the nutrition education intervention showed some changes in the prevalence of risk factors, significant changes require more intensive, long-term interventions tailored to individual needs.

An NIR-responsive hydrogel loaded with polydeoxyribonucleotide nano-vectors for enhanced chronic wound healing

Chronic diabetic wounds are difficult to treat due to imbalanced inflammatory responses, high blood glucose levels, and bacterial infections. Novel therapeutic approaches based on nucleic acid analogues have been proposed, with unique advantages in improving angiogenesis, increasing collagen synthesis, and exerting anti-inflammatory effects. However, the inherent electronegativity of nucleic acids makes them less susceptible to cellular uptake. In this paper, a kind of near infrared (NIR)-responsive nanocomposite hydrogel loaded with nucleic acid vectors was proposed for promoting wound healing. The redox system composed of molybdenum disulphide nanosheets (MoS2 NSs) initiated the copolymerization of quaternized chitosan containing double bonds and N-isopropylacrylamide (NIPAAm) to form the matrix. In addition, MoS2 NSs with photothermal conversion performance endow the nanocomposite hydrogel to have NIR-response property and act as physical crosslinking points in the matrix. Polydeoxyribonucleotides (PDRN), which have the effect of promoting wound healing, were made into nucleic acid vectors, and loaded into the NIR-responsive hydrogel. MoS2 NSs can convert NIR irradiation into heat, causing phase transitions of temperature-sensitive segments that trigger volume contraction of the hydrogel to extrude the nucleic acid vector. Promoting angiogenesis, slowing inflammation, and guiding tissue regeneration were demonstrated in the diabetic wound model treated with the NIR-responsive nanocomposite hydrogel.

Hepatitis B virus X protein differentially regulates the angiogenesis of Hepatocellular Carcinoma through p53-VEGF axis according to glucose levels

Introduction and ObjectivesBlood glucose fluctuates severely in the diabetes (DM) and tumor microenvironment. Our previous works have found Hepatitis B virus X protein (HBx) differentially regulated metastasis and apoptosis of hepatoma cells depending on glucose concentration. We here aimed to explore whether HBx played dual roles in the angiogenesis of hepatocellular carcinoma varying on different glucose levels. Materials and MethodsWe collected conditioned medium from HBx-overexpressing cells cultured with two solubilities of glucose, and then applied to EA.hy926 cells. Alternatively, a co-culture cell system was established with hepatoma cells and EA.hy926 cells. We analyzed the angiogenesis of EA.hy926 cells with CCK8, wound-healing, transwell-migartion and tube formation experiment. ELISA was conducted to detect the secretion levels of angiogenesis-related factors. siRNAs were used to detect the P53-VEGF axis. ResultsHBx expressed in hepatoma cells suppressed VEGF secretion, and subsequently inhibited the proliferation, migration and tube formation of EA.hy926 cells in a high glucose condition, while attenuating these in the lower glucose condition. Furthermore, the p53-VEGF axis was required for the dual role of HBx in angiogenesis. Additionally, HBx mainly regulated the nuclear p53. ConclusionsThese data suggest that the dual roles of HBx confer hepatoma cells to remain in a glucose-rich environment and escape from the glucose-low milieu through tumor vessels, promoting liver tumor progression overall. We exclusively revealed the dual role of HBx on the angiogenesis of liver tumors, which may shed new light on the mechanism and management strategy of HBV- and DM-related hepatocellular carcinoma.

Maltol Improves Peripheral Nerve Function by Inhibiting Schwann Cell Apoptosis via the PERK/eIF2α/CHOP Pathway and MME Upregulation in Diabetic Peripheral Neuropathy.

Diabetic peripheral neuropathy (DPN) is the most prevalent chronic complication among diabetic patients and a primary risk factor contributing to the deterioration of diabetic foot conditions. The pathogenesis of DPN remains complex and not fully understood, and there are hardly any effective treatment drugs. Maltol (3-hydroxy-2-methyl-4-pyranone) has demonstrated antioxidant and anti-inflammatory properties. However, the potential role of maltol in the treatment of DPN remains unclear. This study aimed to assess maltol's effects on DPN rats and high glucose (HG)/palmitic acid (PA)-induced rat Schwann cells (RSC96). The results indicated maltol's capacity to enhance peripheral nerve function in DPN rats. In RSC96 cells stimulated with high HG and PA, maltol treatment reduced DPN markers and apoptosis-related proteins. Functional enrichment analysis of differentially expressed genes revealed that endoplasmic reticulum (ER) stress pathways were involved in this process. Western blot results demonstrated the activation of ER stress pathway in HG/PA-induced RSC96 cells, with maltol attenuating ER stress-related protein expression. Furthermore, the knockdown of Membrane metallo-endopeptidase (MME) reversed maltol's effects on apoptosis-related protein expression, suggesting a potential therapeutic role for maltol via MME in treating DPN. These findings indicate that maltol may hold promise as a therapeutic agent for DPN treatment.

Picroside Ⅱ alleviates renal fibrosis through YY1-dependent transcriptional inhibition of TGFβ1

Diabetic Nephropathy (DN) has become the leading cause of end-stage renal disease worldwide. Studies have indicated that Transforming Growth Factor beta1 (TGFβ1) is the most potent factor contributing to renal fibrosis, and understanding the exact pathogenic mechanism of renal fibrosis is crucial for alleviating the condition. Previous research has identified Yin Yang 1 (YY1) as an effective inhibitor of TGF-β1. Our study, through dual-luciferase reporter gene assays and Western blot experiments, screened and obtained the small molecule compound PdⅡ. Subsequently, validation in a high-glucose-induced renal mesangial cell injury model showed that PdⅡ treatment significantly increased the expression of YY1 protein and mRNA, while correspondingly reducing the expression of TGFβ1 protein and mRNA. Dual-luciferase reporter gene assay results revealed that, compared to the control group, the luciferase transcription activity of YY1 molecules increased in the PdⅡ treatment group, and the luciferase transcription activity of TGFβ1 decreased. By further designing mutations in the binding sites between TGFβ1 and YY1 on the promoter, transfecting fluorescent enzyme reporter gene plasmids with TGFβ1 mutant promoter into mesangial cells damaged by high glucose, and then treating the cells with PdⅡ, it was observed that the luciferase transcription activity of TGFβ1 did not decrease. Therefore, these results suggest that PdⅡ may inhibit TGFβ1 transcriptional activity by activating YY1, thereby slowing down the progression of diabetic nephropathy.

Predicting the risk of type 2 diabetes: Standardized diabetes risk score among the Khmer ethnic minority in Vietnam.

Predicting the risk of progression to type 2 diabetes, as well as identifying the factors that increase this risk, helps the population adjust the modifiable risk factors, improve quality of life, and reduce the disease burden. A cross-sectional study was conducted on 918 ethnic Khmer minority people aged 40 and above in Vietnam who had never been diagnosed with type 2 diabetes. To predict the 10-year risk of type 2 diabetes, the Finnish Diabetes Risk Scoring Scale, adjusted for the Asian population with modification of the waist circumpherence and Body Mass Index Cut-Offs, was used. The 10-year predicted risk of progression to type 2 diabetes in ethnic Khmer people aged 40 years and older in southern Vietnam, using the Asian-modified Finnish Diabetes Risk Scoring Scale, resulted 10.54% in the total population study, females have a higher risk at 12.62% compared to 8.01% of males. Among the items that make up the Finnish Diabetes Risk Scoring Scale, age, waist circumference, BMI, family history of diabetes, history of high blood glucose, and use of blood pressure medication were the most accurate predictors, with the area under the Receiver operating characteristic (ROC) curve at 0.83, 0.81, 0.77, 0.75, 0.74 and 0.73 respectively. The optimal cut-off score to identify progression to tipe 2 diabetes was 13.5 points (Se = 1.00, Sp = 1.00, p < 0.001). The multivariable logistic regression model shows that factors associated with high risk of type 2 diabetes progression in 10 years are age, gender, occupation, economic status, education level and regular alcohol consumption (p < 0.05). The study results provide a basis for proposing potential solutions to reduce modifiable risk factors for type 2 diabetes in the population. These include providing culturally appropriate health education and changing behavior to address alcohol consumption. The use of the Asian-modified Finnish Diabetes Risk Scoring Scale to predict the risk of progression to type 2 diabetes and as a screening tool for undiagnosed type 2 diabetes is appropriate for the Vietnamese Khmer population.

Urolithin A Ameliorates the TGF Beta-Dependent Impairment of Podocytes Exposed to High Glucose.

Increased activity of transforming growth factor-beta (TGF-β) is a key factor mediating kidney impairment in diabetes. Glomerular podocytes, the crucial component of the renal filter, are a direct target of TGF-β action, resulting in irreversible cell loss and progression of chronic kidney disease (CKD). Urolithin A (UA) is a member of the family of polyphenol metabolites produced by gut microbiota from ellagitannins and ellagic acid-rich foods. The broad spectrum of biological activities of UA makes it a promising candidate for the treatment of podocyte disorders. In this in vitro study, we investigated whether UA influences the changes exerted in podocytes by TGF-β and high glucose. Following a 7-day incubation in normal (NG, 5.5 mM) or high (HG, 25 mM) glucose, the cells were treated with UA and/or TGF-β1 for 24 h. HG and TGF-β1, each independent and in concert reduced expression of nephrin, increased podocyte motility, and up-regulated expression of b3 integrin and fibronectin. These typical-for-epithelial-to-mesenchymal transition (EMT) effects were inhibited by UA in both HG and NG conditions. UA also reduced the typically elevated HG expression of TGF-β receptors and activation of the TGF-β signal transducer Smad2. Our results indicate that in podocytes cultured in conditions mimicking the diabetic milieu, UA inhibits and reverses changes underlying podocytopenia in diabetic kidneys. Hence, UA should be considered as a potential therapeutic agent in podocytopathies.

Analysis of metabolic alterations as 30 days intensive care mortality predictors for patients undergoing continuous renal replacement therapy

BackgroundAcute kidney injury patients on continuous renal replacement therapy are subjected to alterations in metabolism, which in turn are associated with worse clinical outcome and mortality. The aim of this study is to determine which metabolism indicators can be used as independent predictors of 30 days intensive care unit (ICU) mortality. MethodsThis was a prospective observational study on critical care patients on renal replacement therapy. Integrated approach of metabolism evaluation was used, combining the energy expenditure measured by indirect calorimetry, bioelectrical impedance provided fat free mass index (FFMI), amino acid and glucose concentrations. ICU mortality was defined as all cause 30 days mortality. Regression analysis was conducted to determine the conventional and metabolism associated predictors of mortality. ResultsThe study was conducted between the 2021 March and 2022 October. 60 high mortality risk patients (APACHE II of 22.98±7.87, 97% on vasopressors, 100% on mechanical ventilation) were included during the period of the study. The rate of 30 days ICU mortality was 50% (n=30). Differences across survivors and non-survivors in metabolic predictors were noted in energy expenditure (kcal/kg/day) (19.79 ±5.55 vs 10.04 ±3.97 p=0.013), amino acid concentrations (mmol/L) (2.40 ±1.06 vs 1.87 ±0.90 p=0.040) and glucose concentrations (mmol/L) (7.89 ±1.90 vs 10.04 ±3.97 p=0.010). No differences were noted in FFMI (23.38 ±4.25 vs 21.95 ±3.08 p=0.158). In the final linear regression analysis model, lower energy expenditure (exp(B)= 0.852 CI95%: 0.741-0.979 p=0.024) and higher glucose (exp(B)=1.360 CI95%: 1.013-1.824 p=0.041) remained as independent predictors of the higher mortality. ConclusionThe results of the study imply strong association between the metabolic alterations and ICU outcome. Our findings suggest that lower systemic amino acid concentration, lower energy expenditure and higher systemic glucose concentration are predictive of 30 days ICU mortality.

Identification and functional characterization of differentially expressed circRNAs in high glucose treated endothelial cells: Construction of circRNA-miRNA-mRNA network

BackgroundEndothelial dysfunction is a complication of diabetes mellitus (DM), characterized by impaired endothelial function in both microvessels and macrovessels, closely linked to atherosclerosis (AS). Endothelial dysfunction, characterized by impaired endothelial cell (EC) function, is a pivotal factor in AS and DM. Circular RNAs (circRNAs) are endogenous non-coding RNAs that can act as competing endogenous RNAs (ceRNAs) and regulate gene expression. However, the role of circRNAs in ECs dysfunction and AS under high glucose (HG) condition remains elusive. MethodsWe performed high-throughput sequencing to identify differentially expressed (DE) circRNAs in human umbilical vein endothelial cells (HUVEC) exposed to HG, one risk factors of endothelial dysfunction and AS. We then validated eight candidate circRNAs by qRT-PCR and functional analysis, directing our attention to hsa_circ_0122319. Moreover, microarray analysis identified the differential expression profiles of miRNAs and mRNAs regulated by hsa_circ_0122319. Subsequently, the construction of the ceRNAs network employed bioinformatic analysis and Cytoscape software. Furthermore, the role of the PI3K-Akt signaling pathway in regulating ceRNAs was evaluated. ResultsWe detected 917 DE circRNAs in HG treated HUVEC. The parental genes of these circRNAs were enriched in cell cycle, cellular senescence and endocytosis related pathways. The differential expression of hsa_circ_0122319 was confirmed to be most obvious at the cellular level and in clinical samples by qPCR experiments. After overexpression of hsa_circ_0122319, 49 DE miRNAs and 459 DE mRNAs were identified using microarray analysis. Subsequently, a ceRNAs network was constructed, comprising hsa_circ_0122319, 8 miRNAs, and 41 mRNAs. ConclusionIn summary, our study delves into the role of circRNAs in endothelial dysfunction associated with DM and AS. Through high-throughput sequencing and validation, we identified hsa_circ_0122319 as a pivotal regulator of ECs function under HG conditions. It also showed that hsa_circ_0123319 has the potential to serve as a biomarker for DM and its vascular complications, and provides new evidence for future exploration of the intricate molecular mechanisms of endothelial dysfunction in the progression of DM and AS.

Endoplasmic reticulum stress induces hepatic steatosis through interaction between PPARα and FoxO6 in vivo and in vitro

Endoplasmic reticulum (ER) stress is a major cause of hepatic steatosis through increasing de novo lipogenesis. Forkhead box O6 (FoxO6) is a transcription factor mediating insulin signaling to glucose and lipid metabolism. Therefore, dysregulated FoxO6 is involved in hepatic lipogenesis. This study elucidated the role of FoxO6 in ER stress–induced hepatic steatosis in vivo and in vitro. Hepatic ER stress responses and β-oxidation were monitored in mice overexpressed with constitutively active FoxO6 allele and FoxO6-null mice. For the in vitro study, liver cells overexpressing constitutively active FoxO6 and FoxO6-siRNA were treated with high glucose, and lipid metabolism alterations were measured. ER stress–induced FoxO6 activation suppressed hepatic β-oxidation in vivo. The expression and transcriptional activity of peroxisome proliferator-activated receptor α (PPARα) were significantly decreased in the constitutively active FoxO6 allele. Otherwise, inhibiting β-oxidation genes were reduced in the FoxO6-siRNA and FoxO6-KO mice. Our data showed that the FoxO6-induced hepatic lipid accumulation was negatively regulated by insulin signaling. High glucose treatment as a hyperglycemia condition caused the expression of ER stress–inducible genes, which was deteriorated by FoxO6 activation in liver cells. However, high glucose-mediated ER stress suppressed β-oxidation gene expression through interactions between PPARα and FoxO6 corresponding to findings in the in vivo study—lipid catabolism is also regulated by FoxO6. Furthermore, insulin resistance suppressed b-oxidation through the interaction between FoxO6 and PPARα promotes hepatic steatosis, which, due to hyperglycemia-induced ER stress, impairs insulin signaling.Key messagesOur original aims were to delineate the interrelation between the regulation of PPARα and the transcription factor FoxO6 pathway in relation to lipid metabolism at molecular levels.Evidence on high glucose promoted FoxO6 activation induced lipid accumulation in liver cells.The effect of PPARα activation of the insulin signaling.FoxO6 plays a pivotal role in hepatic lipid accumulation through inactivation of PPARα in FoxO6-overexpression mice.