CERS6-derived ceramides aggravate kidney fibrosis by inhibiting PINK1-mediated mitophagy in diabetic kidney disease.

During diabetic kidney disease (DKD), ectopic ceramide (CER) accumulation in renal tubular epithelial cells (RTECs) is associated with interstitial fibrosis and albuminuria. As RTECs are primarily responsible for renal energy metabolism, their function is intimately linked to mitochondrial quality control. The role of CER synthesis in the progression of diabetic renal fibrosis has not been thoroughly investigated. In this study, we observed a significant upregulation of ceramide synthase 6 (Cers6) expression in the renal cortex of db/db mice, coinciding with increased production of CER (d18:1/14:0) and CER (d18:1/16:0) by Cer6. Concurrently, the number of damaged mitochondria in RTECs rose. Cers6 deficiency reduced the abnormal accumulation of CER (d18:1/14:0) and CER (d18:1/16:0) in the kidney cortex, restoring the PTEN-induced kinase 1 (PINK1)-mediated mitophagy in RTECs, and resulting in a decrease in damaged mitochondria and attenuation of interstitial fibrosis in DKD. Automated docking analysis suggested that both CER (d18:1/14:0) and CER (d18:1/16:0) could bind to the PINK1 protein. Furthermore, inhibiting PINK1 expression in CERS6 knockdown HK-2 cells diminished the therapeutic effect of CERS6 deficiency on DKD. In summary, CERS6-derived CER (d18:1/14:0) and CER (d18:1/16:0) inhibit PINK1-regulated mitophagy by possibly binding to the PINK1 protein, thereby exacerbating the progression of renal interstitial fibrosis in DKD.NEW & NOTEWORTHY This article addresses the roles of ceramide synthase 6 (CERS6) and CERS6-derived ceramides in renal tubular epithelial cells of diabetic kidney disease (DKD) associated interstitial fibrosis. Results from knockdown of CERS6 adjusted the ceramide pool in kidney cortex and markedly protected from diabetic-induced kidney fibrosis in vivo and in vitro. Mechanically, CERS6-derived ceramides might interact with PINK1 to inhibit PINK1/Parkin-mediated mitophagy and aggravate renal interstitial fibrosis in DKD.

Long noncoding RNA XIST regulates brown preadipocytes differentiation and combats high-fat diet induced obesity by targeting C/EBPα.

BACKGROUND: Activation of brown adipose tissue (BAT) increases energy expenditure, which makes it an attractive therapeutic strategy for obesity. LncRNAs play an important role in adipocyte differentiation and regulation. Here we assessed the effect of lncRNA XIST on brown preadipocytes differentiation and metabolic regulation. METHODS: XIST expression levels were detected in human perirenal (peri-N) and subcutaneous adipose tissues (sub-Q), brown preadipocytes and 3T3-L1 preadipocytes. XIST overexpression and knockdown experiments were performed in brown preadipocytes. XIST overexpression mouse model was established by plasmid injection through tail vein. RESULTS: In human adipose tissues, XIST expression was significantly higher in female than in male individuals. In vitro, XIST expression was significantly up-regulated during brown adipocyte differentiation. XIST knockdown inhibited differentiation of brown preadipocytes, while overexpression of XIST promotes brown preadipocytes to fully differentiation. RNA Binding Protein Immunoprecipitation (RIP) experiment revealed that XIST could directly bind to C/EBPα. In vivo, XIST overexpression prevents high-fat diet induced obesity and improves metabolic dysorder in male mice. CONCLUSION: Our results suggest that XIST combats obesity through BAT activation at least partly by combination with transcription factor C/EBPα.

The HDAC2/SP1/miR-205 feedback loop contributes to tubular epithelial cell extracellular matrix production in diabetic kidney disease.

Extracellular matrix (ECM) accumulation is considered an important pathological feature of diabetic kidney disease (DKD). Histone deacetylase (HDAC) inhibitors protect against kidney injury. However, the potential mechanisms of HDACs in DKD are still largely unknown. Here, we describe a novel feedback loop composed of HDAC2 and miR-205 that regulates ECM production in tubular epithelial cells in individuals with DKD. We found that HDAC2 mRNA expression in peripheral blood was markedly higher in patients with DKD than in patients with diabetes. Nuclear HDAC2 protein expression was increased in TGFß1-stimulated tubular epithelial cells and db/db mice. We also found that miR-205 was regulated by HDAC2 and down-regulated in TGFß1-treated HK2 cells and db/db mice. In addition, HDAC2 reduced histone H3K9 acetylation in the miR-205 promoter region to inhibit its promoter activity and subsequently suppressed miR-205 expression through an SP1-mediated pathway. Furthermore, miR-205 directly targeted HDAC2 and inhibited HDAC2 expression. Intriguingly, miR-205 also regulated its own transcription by inhibiting HDAC2 and increasing histone H3K9 acetylation in its promoter, forming a feedback regulatory loop. Additionally, the miR-205 agonist attenuated ECM production in HK2 cells and renal interstitial fibrosis in db/db mice. In conclusion, the HDAC2/SP1/miR-205 feedback loop may be crucial for the pathogenesis of DKD.

Exenatide and Renal Outcomes in Patients with Type 2 Diabetes and Diabetic Kidney Disease.

BACKGROUND: Cardiovascular outcomes in clinical trials with type 2 diabetes mellitus (T2DM) patients have shown that glucagon-like peptide-1 receptor agonist can have a beneficial effect on the kidney. This trial aimed to assess the effects of exenatide on renal outcomes in patients with T2DM and diabetic kidney disease (DKD). METHODS: We performed a randomized parallel study encompassing 4 general hospitals. T2DM patients with an estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m2 and macroalbuminuria, defined as 24-h urinary albumin excretion rate (UAER) >0.3 g/24 h were randomized 1:1 to receive exenatide twice daily plus insulin glargine (intervention group) or insulin lispro plus glargine (control group) for 24 weeks. The primary outcome was the UAER percentage change from the baseline after 24 weeks of intervention. The rates of hypoglycemia, adverse events (AEs), and change in eGFR during the follow-up were measured as safety outcomes. RESULTS: Between March 2016 and April 2019, 92 patients were randomized and took at least 1 dose of the study drug. The mean age of the participants was 56 years. At baseline, the median UAER was 1,512.0 mg/24 h and mean eGFR was 70.4 mL/min/1.73 m2. After 24 weeks of treatment, the UAER percentage change was significantly lower in the intervention group than in the control group (p = 0.0255). Moreover, the body weight declined by 1.3 kg in the intervention group (the difference between the 2 groups was 2.7 kg, p = 0.0001). Compared to the control group, a lower frequency of hypoglycemia and more gastrointestinal AEs were observed in the intervention group. CONCLUSION: Exenatide plus insulin glargine treatment for 24 weeks resulted in a reduction of albuminuria in T2DM patients with DKD.

Extracellular Vesicles from Albumin-Induced Tubular Epithelial Cells Promote the M1 Macrophage Phenotype by Targeting Klotho.

Albumin absorbed by renal tubular epithelial cells induces inflammation and plays a key role in promoting diabetic kidney disease (DKD) progression. Macrophages are prominent inflammatory cells in the kidney, and their role there is dependent on their phenotypes. However, whether albuminuria influences macrophage phenotypes and underlying mechanisms during the development of DKD is still unclear. We found that M1 macrophage-related markers were increased in diabetes mellitus (DM) mouse renal tissues with the development of DKD, and coculture of extracellular vesicles (EVs) from human serum albumin (HSA)-induced HK-2 cells with macrophages induced macrophage M1 polarization in the presence of lipopolysaccharide (LPS). Through a bioinformatic analysis, miR-199a-5p was selected and found to be increased in EVs from HSA-induced HK-2 cells and in urinary EVs from DM patients with macroalbuminuria. Tail-vein injection of DM mice with EVs from HSA-induced HK-2 cells induced kidney macrophage M1 polarization and accelerated the progression of DKD through miR-199a-5p. miR-199a-5p exerted its effect by targeting Klotho, and Klotho induced macrophage M2 polarization through the Toll-like receptor 4 (TLR4) pathway both in vivo and in vitro. In summary, miR-199a-5p from HSA-stimulated HK-2 cell-derived EVs induces M1 polarization by targeting the Klotho/TLR4 pathway and further accelerates the progression of DKD.

MiR-4756 promotes albumin-induced renal tubular epithelial cell epithelial-to-mesenchymal transition and endoplasmic reticulum stress via targeting Sestrin2.

Accumulating evidence indicates that proteinuria promotes the progression of diabetic kidney disease (DKD) and induces renal epithelial tubular cell epithelial-to-mesenchymal transition (EMT) and endoplasmic reticulum (ER) stress, but the mechanism remains unclear. In our previous research, we found that miR-4756 levels were increased in the urinary extracellular vesicles of type 2 diabetes mellitus patients with macroalbuminuria. In a preliminary study, we found that miR-4756 may be derived from renal tubular epithelial cells, but its role has not been elucidated. Albumin stimulation significantly increased miR-4756 levels in HK-2 cells. In addition, an miR-4756 mimic accelerated albumin-stimulated HK-2 cell EMT and ER stress, and an miR-4756 inhibitor suppressed these events. We then found that miR-4756 targeted the 3'-untranslated region (UTR) of Sestrin2 and directly suppressed Sestrin2 expression. Furthermore, the induction of EMT and ER stress by the overexpression of miR-4756 was abolished by Sestrin2 overexpression. Moreover, the overexpression of miR-4756 increased ERK1/2 activation and decreased 5' monophosphate-activated protein kinase activation. Thus, our study provides evidence that miR-4756 accelerates the process of DKD through Sestrin2, suggesting that targeting miR-4756 may be a novel strategy for DKD treatment.

Genetic Analysis of SLC12A3 Gene in Chinese Patients with Gitelman Syndrome.

BACKGROUND The incidence of Gitelman syndrome (GS) has been increasing in our hospital. The aim of this study was to explore the diagnostic accuracy and features of SLC12A3 gene in Chinese patients with GS. MATERIAL AND METHODS We searched the literature about Chinese patients with GS in the PubMed database up to July 2018 and also included 8 GS Chinese patients from our hospital in our analysis that explored the features of SLC12A3 gene. We divided all the patients into 3 groups according to diagnostic consensus. Complete compliance was defined to mean containing 2 allelic mutations, partial compliance to mean one allelic mutation, and clinical compliance to mean no mutations. RESULTS Totally, 137 patients were enrolled in this study and 90 mutations were counted. Missense mutations accounted for over 72% in Chinese GS patients and the most common one was Thr60Met. According to the consensus, there were 102 patients (74.5%) in the complete compliance group, 31 patients (22.6%) in the partial compliance group, and only 4 patients (2.9%) in the clinical compliance group. CONCLUSIONS The SLC12A3 gene analysis in Chinese GS patients revealed that the most common mutation was Thr60Met, one of the missense mutations. Most of the patients were in the complete compliance group (i.e., 2 allelic mutations); the other cases might be explained by gene rearrangement.

Bitter melon (Momordica charantia) attenuates atherosclerosis in apo-E knock-out mice possibly through reducing triglyceride and anti-inflammation.

BACKGROUND: Bitter melon (BM, Momordica charantia) has been accepted as an effective complementary treatment of metabolic disorders such as diabetes, hypertension, dyslipidemia and etc. However it is unclear whether BM can prevent the progression of atherosclerosis. To confirm the effects of BM on atherosclerosis and explore its underlying mechanisms, we design this study. METHODS: Twenty four male apolipoprotein E knock-out (ApoE-/-) mice aged 8 weeks were randomly divided into control group fed with high fat diet (HFD) only and BM group fed with HFD mixed with 1.2%w/w BM. After 16 weeks, body weight, food intake, blood glucose, serum lipids were measured and the atherosclerotic plaque area and its histological composition were analyzed. The expression of vascular cell adhesive molecules and inflammatory cytokines in the aortas were determined using quantitative polymerase chain reaction. RESULTS: Body weight gain and serum triglycerides (TG) significantly decreased in BM group. BM reduced not only the atherosclerotic plaque area and the contents of collagen fibers in atherosclerotic plaques but also the serum soluble vascular cell adhesion molecule (VCAM)-1 and P-selectin levels, as well as the expressions of monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-6 in aortas. CONCLUSION: Our study indicates that dietary BM can attenuate the development of atherosclerosis in ApoeE-/- mice possibly through reducing triglyceride and anti-inflammation mechanism.

Klotho down-regulates Egr-1 by inhibiting TGF-ß1/Smad3 signaling in high glucose treated human mesangial cells.

Diabetic kidney disease (DKD) has become the leading cause of end-stage renal disease worldwide and is associated with glomerular mesangial cell (MC) proliferation and excessive extracellular matrix (ECM) production. Klotho can attenuate renal fibrosis in part by inhibiting TGF-ß1/Smad3 signaling in DKD. Early growth response factor 1 (Egr-1) has been shown to play a key role in renal fibrosis in part by facilitating the formation of a positive feedback loop involving TGF-ß1. However, whether Klotho down-regulates Egr-1 by inhibiting TGF-ß1/Smad3 signaling in DKD is unclear. In the present study, we assessed human MCs that were incubated under high-glucose conditions to mimic diabetes. Then, we transfected the cells with Klotho plasmid or siRNA to overexpress or knock down Klotho gene and protein expression. Klotho, Egr-1, fibronectin (FN), collagen type I (Col I), Smad3 and phosphorylated Smad3 (p-Smad3) gene and protein expression levels were determined by RT-qPCR and western blotting respectively. High glucose time-dependently down-regulated Klotho mRNA and protein expression in cultured human MCs. pcDNA3.1-Klotho transfection-mediated Klotho overexpression down-regulated Egr-1, FN and Col I expression and the p-Smad3/Smad3 ratio in human MCs. Conversely, siRNA-mediated Klotho silencing up-regulated Egr-1, FN, and Col I expression and the p-Smad3/Smad3 ratio. Moreover, the effects of si-Klotho on Egr-1 expression were abolished by the TGF-ß1 inhibitor SB-431542. Klotho overexpression can prevent mesangial ECM production in high-glucose-treated human MCs, an effect that has been partially attributed to Egr-1 down-regulation facilitated by TGF-ß1/Smad3 signaling inhibition.

MicroRNA-455 regulates brown adipogenesis via a novel HIF1an-AMPK-PGC1α signaling network.

Brown adipose tissue (BAT) dissipates chemical energy as heat and can counteract obesity. MicroRNAs are emerging as key regulators in development and disease. Combining microRNA and mRNA microarray profiling followed by bioinformatic analyses, we identified miR-455 as a new regulator of brown adipogenesis. miR-455 exhibits a BAT-specific expression pattern and is induced by cold and the browning inducer BMP7. In vitro gain- and loss-of-function studies show that miR-455 regulates brown adipocyte differentiation and thermogenesis. Adipose-specific miR-455 transgenic mice display marked browning of subcutaneous white fat upon cold exposure. miR-455 activates AMPKα1 by targeting HIF1an, and AMPK promotes the brown adipogenic program and mitochondrial biogenesis. Concomitantly, miR-455 also targets the adipogenic suppressors Runx1t1 and Necdin, initiating adipogenic differentiation. Taken together, the data reveal a novel microRNA-regulated signaling network that controls brown adipogenesis and may be a potential therapeutic target for human metabolic disorders.

Comparison of Prednisolone, Etoricoxib, and Indomethacin in Treatment of Acute Gouty Arthritis: An Open-Label, Randomized, Controlled Trial.

BACKGROUND: At present there are several kinds of medicine for treating acute gout arthritis (AGA). This study compared the efficacy and safety of prednisolone, etoricoxib, and indomethacin in the treatment of AGA. MATERIAL/METHODS: This was an open-label, randomized, active-comparator study in patients with AGA. Patients were randomized to 4 days of prednisolone 35 mg qd, etoricoxib 120 mg qd, or indomethacin 50 mg tid. The primary efficacy endpoint was the reduction of self-assessed pain in the index joint from baseline. Secondary endpoints included changes in physician's assessment of tenderness, erythema, swelling, and joint activity; patient assessment of response to therapy; and safety. RESULTS: We analyzed 113 patients. Baseline demographics were comparable among treatment groups. Oral prednisolone, etoricoxib, and indomethacin were similarly effective in improving pain, tenderness, and joint activity over 4 days. For inflammation, oral prednisolone, etoricoxib, and indomethacin were similarly effective in reducing erythema, but prednisolone might be more effective in reducing swelling than indomethacin. The patient response to therapy was similar in the 3 groups. There were more total adverse events with indomethacin compared with the other 2 drugs. CONCLUSIONS: Efficacy was comparable among prednisolone, etoricoxib, and indomethacin for the treatment of AGA. Prednisolone might be more effective in reducing inflammation and it had a better safety profile.

Transcription Factor Egr1 is Involved in High Glucose-Induced Proliferation and Fibrosis in Rat Glomerular Mesangial Cells.

UNLABELLED: Backgroud: Diabetic nephropathy is one of the most frequent causes of end-stage renal disease and is associated with proliferation of glomerular mesangial cells (MCs) and excessive production of the extracellular matrix (ECM). Several studies have shown that early growth response factor 1 (Egr1) plays a key role in renal fibrosis by regulating the expression of genes encoding ECM components. However, whether Egr1 also contributes to diabetic nephropathy is unclear. METHODS: In the present study, we compared the expression of Egr1 in kidneys from OLETF rats with spontaneous type 2 diabetes and healthy LETO rats. We also examined whether high glucose and TGF-ß1 signaling up-regulated Egr1 expression in cultured MCs, and whether Egr1 expression influenced MC proliferation and expression of ECM genes. RESULTS: We found that higher expression of Egr1 and TGF-ß1, at both the mRNA and protein levels, the kidneys from OLETF rats vs. LETO rats. High glucose or TGF-ß1 signaling rapidly up-regulated expression of Egr1 mRNA and protein in cultured MCs. Overexpressing Egr1 in MCs by transfection with M61-Egr1 plasmid or treatment with high glucose up-regulated expression of fibronectin, type IV collagen and TGF-ß1, and promoted MC proliferation. Conversely, siRNA-mediated silencing of Egr1 expression down-regulated these genes and inhibited MC proliferation. Chromatin immunoprecipitation (ChIP) assays revealed that Egr1 bound to the TGF-ß1 promoter. CONCLUSION: Our results provide strong evidence that Egr1 contributes to diabetic nephropathy by enhancing MC proliferation and ECM production, in part by interacting with TGF-ß1.

Exendin-4 alleviates high glucose-induced rat mesangial cell dysfunction through the AMPK pathway.

BACKGROUND/AIMS: Glucagon-like peptide-1 (GLP-1), which counteracts insulin resistance in humans with type 2 diabetes, has been shown to ameliorate diabetic nephropathy in experimental models. However, the mechanisms through which GLP-1 modulates renal function remained illdefined. The present study investigated the putative mechanisms underlying effects of exendin-4, a GLP-1 analog, on mesangial cell proliferation and fibronectin. METHODS: Rat mesangial cells (MCs) were treated with exendin-4 under high glucose conditions. AMP-activated protein kinase (AMPK) inhibitors (compound C) and agonists (AICAR) were used to analyze the role of this kinase. Cell proliferation was measured using a MTT assay. Fibronectin expression and AMPK-signaling pathway activity were assessed using ELISA and Western blotting, respectively. The production of matrix metalloproteinase (MMP)-2 and tissue inhibitors of metalloproteinases (TIMP)-2 was evaluated using quantitative real-time RT-PCR. RESULTS: Exendin-4 inhibited cell proliferation and fibronectin secretion in high glucose-induced MCs. It also caused phosphorylation of AMPK and subsequently increased the ratio of MMP-2 to TIMP-2, which resulted in the degradation of fibronectin. Exendin-4 reversed extracellular signal-regulated kinase (ERK) phosphorylation and enhanced expression of mammalian target of rapamycin (mTOR) in MCs. Moreover, the activation of the AMPK pathway by exendin-4 was induced by AICAR, which was inhibited by compound C. CONCLUSION: Exendin-4 exerts an inhibitory effect on cell proliferation and fibronectin secretion in rat MCs, partly through AMPK activation. These results may explain some of the beneficial effects of exendin-4 on the kidney.

The DPP-4 inhibitor sitagliptin attenuates the progress of atherosclerosis in apolipoprotein-E-knockout mice via AMPK- and MAPK-dependent mechanisms.

BACKGROUND: The dipeptidyl peptidase-4 inhibitor sitagliptin, a new anti-diabetic medicine, is effective in treating type 2 diabetes mellitus by increasing the activation and duration of action of glucagon-like peptide-1. Since atherosclerosis is the main pathological feature of diabetic cardiovascular complications, it is important to investigate the anti-atherosclerotic effect of sitagliptin and explore the relevant mechanisms. METHODS: Male apolipoprotein-E-knockout mice were randomly divided into two groups and fed either high-fat diet (HFD) or HFD plus sitagliptin at a concentration of 0.3% for 16 weeks. Body weight, food intake, blood glucose, serum lipids and adhesion molecules were measured. The atherosclerotic plaque area and its histological composition were analyzed using Sudan staining and immunohistochemistry. The expression of inflammatory cytokines (monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-6) and the activation of AMP-activated protein kinase (AMPK) and mitogen-activated protein kinase (MAPK) in the aortas were determined using quantitative polymerase chain reaction and western blot, respectively. RESULTS: Mice treated with sitagliptin developed fewer atherosclerotic plaques than the control group (7.64 ± 1.98% vs 12.91 ± 1.15%, p < 0.001), particularly in the aortic arch and abdominal aorta, where plaques were decreased 1.92- and 2.74-fold, respectively (p < 0.05 and p < 0.01). Sitagliptin significantly reduced the content of collagen fiber in plaques 1.2-fold (p < 0.05). Moreover, sitagliptin significantly reduced the expression of monocyte chemoattractant protein-1 and interleukin-6 in the aorta (p < 0.01 and p < 0.05), as well as the serum levels of soluble vascular cell adhesion molecule-1 and P-selectin (both p < 0.05). In addition, Sitagliptin induced phosphorylation of AMPK and Akt (p < 0.05 and p < 0.01), while suppressed phosphorylation of p38 and extracellular signal-regulated kinase (Erk) 1/2 (p < 0.05 and p < 0.01) in aortas. CONCLUSIONS: Our present study indicates that sitagliptin can reduce the area of the atherosclerotic lesion, possibly by regulating the AMPK and MAPK pathways and then reducing leukocyte -endothelial cell interaction and inflammation reactions. These actions are independent of weight loss and glucose-reducing effects.

Triiodothyronine regulates distribution of thyroid hormone receptors by activating AMP-activated protein kinase in 3T3-L1 adipocytes and induces uncoupling protein-1 expression.

The purposes of this study were to examine whether thermogenesis in 3T3-L1 adipocytes is related to variations in thyroid hormone receptors (TRs) that are differently regulated by triiodothyronine (T3), and the possible role of AMP-activated protein (AMPK) in thermogenesis after cell differentiation. Differentiated 3T3-L1 adipocytes were maintained under four conditions: normal control group, T3 treatment group, AMPK agonist (5-aminoimidazole-4-carboxamide-1-ß-D-ribofuranoside) treatment group, and T3 and AMPK inhibitor (Compound C) treatment group. Real-time polymerase chain reaction was then performed to evaluate the changes in TRα and TRß mRNA levels in the cells, as well as marker genes for brown adipose tissue including uncoupling protein (UCP)-1 and Cidea. Western blotting was carried out for the cells to detect the expressions of TRα, TRß, and AMPK protein levels. After T3 treatment, the mRNA and protein levels of TRα decreased compared with the control group, while TRß mRNA and protein levels increased markedly at the same time. We also found elevated mRNA levels of UCP-1 and Cidea after exposure to T3. However, the distribution of TRs was reversed by Compound C. AMPK protein levels were clearly activated by T3. Our results suggest that the distribution of TRs is related to thermogenesis, and AMPK may participate in the alterations.

Circulating levels of miR-146a and IL-17 are significantly correlated with the clinical activity of Graves' ophthalmopathy.

Graves' ophthalmopathy (GO) is a common autoimmune disease that is difficult to deal with due to limited clinical evaluation methods. Recently miR-146a and Interleukin-17 (IL-17) have been found to be involved in autoimmune disorders and correlated with disease activity. However, it is unclear whether they are involved in Graves' ophthalmopathy (GO). The aim of this study is to investigate the correlation of circulating levels of miR-146a and IL-17 with clinical activity in GO patients. Fifty-seven study subjects were enrolled in four groups according to the corresponding criteria: active-GO, inactive-GO, Graves disease (GD) without ophthalmopathy, and healthy control group. The circulating levels of miR-146a and IL-17 were determined by qRT-PCR and ELISA, respectively. Serum IL-17 levels of GD, inactive-GO, and active-GO groups were all significantly higher than that of control (all P < 0.001). Active-GO group had significantly higher IL-17 level than inactive-GO and GD groups (P = 0.024 and P = 0.001, respectively). Active-GO and inactive-GO group had significantly lower miR-146a expressions than control (P < 0.05). Active-GO group had significantly lower miR-146a than inactive-GO group (P < 0.05). Serum levels of IL-17 and miR-146a were both significantly correlated with clinical activity score (CAS) in GO patients (P < 0.001, P < 0.001, respectively). There was a significant negative correlation of circulating miR-146a expression with serum IL-17 levels (P < 0.01). These findings indicated that circulating levels of miR-146a and IL-17 may be potential biomarkers of active GO, and may play a key role in the progression of GO.

The dipeptidyl peptidase-4 inhibitor sitagliptin protects against dyslipidemia-related kidney injury in Apolipoprotein E knockout mice.

The goal of this study was to investigate the possible protective effects of sitagliptin against dyslipidemia-related kidney injury in apolipoprotein E knockout (apoE-/-) mice. Eight-week-old male apoE-/- mice were randomized to receive either a high fat diet (HFD, apoE-/- group) or HFD mixed with sitagliptin (sita + apoE-/- group) for 16 weeks. A control group of age- and gender-matched C57BL/6J mice were fed a HFD. The apoE-/- group exhibited increases in body weight and serum lipid levels in addition to high-density lipoprotein, and increases in 24-h urinary 8-hydroxy-2-deoxyguanosine and albuminuria excretion. Decreased insulin sensitivity was also observed in the apoE-/- group. These mice additionally contained enlargements of the glomerular mesangial matrix area, lipid deposition area, and renal interstitium collagen area. The apoE-/- group also demonstrated down-regulation of phosphorylated AMP-activated protein kinase (AMPK), increases in renal mRNA expression of transforming growth factor-beta 1 (TGF-ß1) and fibronectin (FN), and increased protein expression of Akt, TGF-ß1, FN and p38/ERK mitogen-activated protein kinase (MAPK). Sitagliptin treatment successfully ameliorated all the deleterious effects of dyslipidemia tested. To our knowledge, this is the first time that sitagliptin has been shown to reverse the renal dysfunction and structural damage induced by dyslipidemia in apoE-/- mice. Our results suggest that the renoprotective mechanism of sitagliptin may be due to a reduction in Akt levels, a restoration of AMPK activity, and inhibition of TGF-ß1, FN, and p38/ERK MAPK signaling pathways.

Prevalence of Diabetic Kidney Disease with Different Subtypes in Hospitalized Patients with Diabetes and Correlation Between eGFR and LncRNA XIST Expression in PBMCs.

INTRODUCTION: Diabetic kidney disease (DKD) has become the leading cause of end-stage kidney disease (ESKD) in most countries. Recently, long noncoding RNA XIST has been found involved in the development of DKD. METHODS: A total of 1184 hospitalized patients with diabetes were included and divided into four groups based on their estimated glomerular filtration rate (eGFR) and urinary albumin to creatinine ratio (UACR): normal control group (nDKD), DKD with normoalbuminuric and reduced eGFR (NA-DKD), DKD with albuminuria but without reduced eGFR (A-DKD), and DKD with albuminuria and reduced eGFR (Mixed), and then their clinical characteristics were analyzed. Peripheral blood mononuclear cells (PBMCs) of patients with DKD were isolated, and lncRNA XIST expression was detected by real-time quantitative PCR. RESULTS: The prevalence of DKD in hospitalized patients with diabetes mellutus (DM) was 39.9%, and the prevalence of albuminuria and decreased eGFR was 36.6% and 16.2%, respectively. NA-DKD, A-DKD, and Mixed groups accounted for 23.7%, 3.3%, and 12.9%, respectively. Women with DKD had considerably lower levels of lncRNA XIST expression in their PBMCs compared to nDKD. There was a significant correlation between eGFR level and lncRNA XIST expression (R = 0.390, P = 0.036) as well as a negative correlation between HbA1c and lncRNA XIST expression (R = - 0.425, P = 0.027) in female patients with DKD. CONCLUSIONS: Our study revealed that 39.9% of DM inpatients who were admitted to the hospital had DKD. Importantly, lncRNA XIST expression in PBMCs of female patients with DKD was significantly correlated with eGFR and HbA1c.

Comprehensive analysis of epigenomics and transcriptome data to identify potential target genes associated with obesity.

DNA methylation is closely related to the occurrence and development of many diseases, but its role in obesity is still unclear. This study aimed to find the potential differentially methylated genes associated with obesity occurrence and development. By combining methylation and transcriptome analysis, we identified the key genes in adipose tissue affecting the occurrence and development of obesity and revealed the possible molecular mechanisms involved in obesity pathogenesis. We first screened 14 methylation-related differential genes and verified their expression in adipose tissue by quantitative polymerase chain reaction (qPCR). Seven genes with the same expression pattern were identified as key genes, namely, CCRL2, GPT, LGALS12, PC, SLC27A2, SLC4A4, and TTC36. Then, the immune microenvironment of adipose tissue was quantified by CIBERSORT, and we found that the content of M0 macrophages and T follicular helper cells in adipose tissue was significantly increased and decreased, respectively, in the obese group. Furthermore, the relationship between key genes and the immune microenvironment was analyzed. Additionally, the metabolic pathway activity of each sample was calculated based on the ssGSEA algorithm, and the key gene-metabolic network was constructed. Moreover, we performed a CMAP analysis based on the differential genes in adipose tissue to screen out drugs potentially effective in obesity treatment. In conclusion, we identified seven methylation-related key genes closely related to obesity pathogenesis and explored the potential mechanism of their role in obesity. This study provided novel insights into the molecular mechanisms and management of obesity.

miR-23a-3p regulates the inflammatory response and fibrosis in diabetic kidney disease by targeting early growth response 1.

Diabetic kidney disease (DKD) has become the most common cause of chronic kidney disease. Proteinuria is generally considered one of the clinical indicators of renal damage, and it is also closely related to the progression of DKD. Accumulating evidence indicates that proteinuria induces an upregulation of the expression levels of inflammatory cytokines and fibrosis markers in renal tubular epithelial cells, but the mechanism remains unclear. Previously, we showed that early growth response 1 (Egr1) played a key role in renal tubular injury. However, the upstream mechanism of Egr1 in the development of DKD is poorly understood. In this study, we found that albumin stimulation significantly increased the expression levels of Egr1, interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), and fibronectin (FN) in HK-2 cells but decreased miR-23a-3p levels. We then identified that miR-23a-3p targeted the 3' untranslated region (UTR) of Egr1 and directly suppressed the expression of Egr1. Moreover, we found that overexpression and inhibition of miR-23a-3p in HK-2 cells attenuated and promoted the expression of IL-6, TNF-α, and FN, respectively. Additionally, Egr1 silencing reversed the inflammation and fibrosis caused by the miR-23a-3p inhibitor. Thus, we conclude that miR-23a-3p attenuates the development of DKD through Egr1, suggesting that targeting miR-23a-3p may be a novel therapeutic approach for DKD.