OBJECTIVES: To investigate the effect of high glucose on macrophage polarization and the role of immune-responsive gene 1 (IRG1) in mediating its effect. METHODS: RAW264.7 cells were transfected with IRG1-overexpressing plasmid or IRG1 siRNA via electroporation and cultured in either normal or high glucose for 72 h to observe the changes in cell viability and morphology using CCK-8 assay and phase contrast microscopy. The protein levels of IRG1, iNOS, Arg-1, IL-1β and IL-10 in the treated cells were detected with Western blotting, and the fluorescence intensities of iNOS and Arg-1 were detected using immunofluorescence assay. The protein levels of IL-1β and IL-10 in the culture medium were determined with ELISA. RESULTS: High glucose exposure significantly reduced IRG1 and Arg-1 expressions, increased iNOS and IL-1β expressions and IL-1β secretion, and decreased IL-10 level in RAW264.7 cells. Transfection with the IRG1-overexpressing plasmid provided the cells with obvious resistance to high glucose-induced changes in iNOS, Arg-1, IL-1β and IL-10, whereas IRG1 knockdown further enhanced the effects of high glucose exposure on Arg-1 expression and the expression and secretion of IL-10. CONCLUSIONS High glucose promotes M1 polarization of the macrophages possibly through a mechanism to inhibit the expression of IRG1 protein, thus leading to chronic inflammatory response.
Animals ; Mice ; Macrophages/drug effects* ; Glucose/pharmacology* ; Interleukin-10/metabolism* ; Nitric Oxide Synthase Type II/metabolism* ; RAW 264.7 Cells ; Interleukin-1beta/metabolism* ; Arginase/metabolism* ; RNA, Small Interfering/genetics* ; Transfection ; Inflammation

OBJECTIVES: To investigate the protective effect of Yiqi Yangyin Huazhuo Tongluo Formula (YYHT) against high glucose-induced injury in mouse renal podocytes (MPC5 cells) and the possible mechanism. METHODS: Adult Wistar rats were treated with 19, 38, and 76 g/kg YYHT or saline via gavage for 7 days to prepare YYHT-medicated or blank sera for treatment of MPC5 cells cultured in high glucose (30 mmol/L) prior to transfection with a miR-21a-5p inhibitor or a miR-21a-5p mimic. The changes in miR-21a-5p expressions and the mRNA levels of FoxO1, PINK1, and Parkin in the treated cells were detected with qRT-PCR, and the protein levels of nephrin, podocin, FoxO1, PINK1, and Parkin were detected with Western blotting. Autophagic activity in the cells were evaluated with MDC staining. The effect of miR-21a-5p mimic on FoxO1 transcription and the binding of miR-21a-5p to FoxO1 were examined with luciferase reporter gene assay and radioimmunoprecipitation assay. RESULTS: MPC5 cells exposed to high glucose showed significantly increased miR-21a-5p expression, lowered expressions of FoxO1, PINK1, and Parkin1 mRNAs, and reduced levels of FoxO1, PINK1, parkin, nephrin, and podocin proteins and autophagic activity. Treatment of the exposed cells with YYHT-medicated sera and miR-21a-5p inhibitor both significantly enhanced the protein expressions of nephrin and podocin, inhibited the expression of miR-21a-5p, increased the mRNA and protein expressions of FoxO1, PINK1 and Parkin, and upregulated autophagic activity of the cells. Transfection with miR-21a-5p mimic effectively inhibited the transcription of FoxO1 and promoted the binding of miR-21a-5p to FoxO1 in MPC5 cells, and these effects were obviously attenuated by treatment with YYHT-medicated sera. CONCLUSIONS YYHT-medicated sera alleviate high glucose-induced injury in MPC5 cells by regulating miR-21a-5p/FoxO1/PINK1-mediated mitochondrial autophagy.
Animals ; MicroRNAs/genetics* ; Podocytes/pathology* ; Drugs, Chinese Herbal/pharmacology* ; Autophagy/drug effects* ; Rats, Wistar ; Protein Kinases/metabolism* ; Rats ; Forkhead Box Protein O1 ; Mice ; Mitochondria/drug effects* ; Ubiquitin-Protein Ligases/metabolism* ; Glucose ; Diabetic Nephropathies ; Male ; Membrane Proteins/metabolism* ; Intracellular Signaling Peptides and Proteins

OBJECTIVES: To investigate the effect of Didang Decoction-medicated serum on autophagy in high glucose (HG)-induced rat glomerular endothelial cells (RGECs) and explore the pathway that mediates its effect. METHODS: Primary RGECs were isolated and cultured using sequential sieving combined with collagenase digestion, followed by identification using immunofluorescence assay for factor VIII. High glucose medium was used to induce RGECs to simulate a diabetic environment, and the effects of Didang Decoction-medicated serum and 3-MA (an autophagy inhibitor), either alone or in combination, on autophagy of HG-exposed cells were evaluated by observing autophagic vacuoles using monodansylcadaverine (MDC) staining. RT-qPCR and Western blotting were employed to measure mRNA and protein expression levels of Beclin-1, p62, LC3B, p-PI3K, p-Akt, and p-mTOR. RESULTS: Compared with the control cells, the HG-exposed RGECs showed significantly reduced autophagic fluorescence intensity, decreased Beclin-1 mRNA expression, increased p62 mRNA expression, downregulated Beclin-1 protein and LC3-II/I ratio, and upregulated p62, p-PI3K, p-Akt, and p-mTOR protein levels. Didang Decoction-medicated serum significantly enhanced autophagic fluorescence intensity in HG-exposed cells, increased Beclin-1 mRNA expression, decreased p62 mRNA expression, upregulated Beclin-1 protein, and downregulated p62, p-PI3K, p-Akt, and p-mTOR protein levels. CONCLUSIONS Didang Decoction-medicated serum enhances autophagy in HG-exposed RGECs by regulating the PI3K/Akt/mTOR signaling pathway, which sheds light on a new therapeutic strategy for diabetic nephropathy.
Animals ; Autophagy/drug effects* ; Signal Transduction/drug effects* ; Rats ; TOR Serine-Threonine Kinases/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Proto-Oncogene Proteins c-akt/metabolism* ; Endothelial Cells/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Glucose ; Cells, Cultured ; Kidney Glomerulus/cytology* ; Rats, Sprague-Dawley

OBJECTIVES: To investigate the mechanism through which salidroside inhibits proliferation of gastric cancer (GC) cells focusing on glucose metabolic reprogramming pathways. METHODS: High-throughput sequencing combined with bioinformatics analysis was employed to identify the potential targets of salidroside in human GC MGC-803 cells. Liposome-mediated transfection experiments were carried out to validate the functional and mechanistic roles of these targets. CCK-8 and colony formation assays were used to assess the effects of salidroside on GC cell viability and clonogenic ability. qRT-PCR, Western blotting, and biochemical assay kits were used to analyze the regulatory effects of salidroside on the miR-1343-3p-OGDHL/PDHB enzyme complex-pyruvate metabolic pathway in GC cells. RESULTS: Bioinformatics analysis suggested that the tumor-suppressive factor miR-1343-3p negatively regulated the key glycolytic enzyme gene oxoglutarate dehydrogenase-like (OGDHL) in GC cells, and OGDHL and pyruvate dehydrogenase E1 subunit beta (PDHB) were both significantly upregulated in GC tissues, which was close by correlated with reduced survival rates of GC patients. In MGC-803 cells, salidroside treatment significantly enhanced the expression level of miR-1343-3p and downregulated OGDHL expression, resulting in disruption of the stability of PDHB, reduced pyruvate oxidative decarboxylation, and consequently decreased production of acetyl-CoA and ATP. CONCLUSIONS Salidroside inhibits GC cell proliferation possibly by regulating the miR-1343-3p-OGDHL/PDHB enzyme complex-pyruvate metabolic pathway, which provides new insights into its anti-tumor mechanisms and suggests new strategies for targeted therapy for GC.
Humans ; Stomach Neoplasms/pathology* ; MicroRNAs/genetics* ; Cell Proliferation/drug effects* ; Glucosides/pharmacology* ; Phenols/pharmacology* ; Cell Line, Tumor ; Glucose/metabolism* ; Pyruvate Dehydrogenase (Lipoamide)/metabolism*

OBJECTIVES: To investigate the role of sphingosine-1-phosphate receptor 5 (S1PR5) in modulating barrier function of mouse brain microvascular endothelial cells with oxygen-glucose deprivation and reoxygenation (OGD/R). METHODS: Mouse brain microvascular endothelial cells (bEnd.3) were exposed to OGD/R to induce barrier dysfunction following treatment with S1PR5-specific agonist A971432 or lentivirus-mediated transfection with a S1PR5-specific siRNA, a S1PR5-overexpressing plasmid, or their respective negative control sequences. The changes in viability and endothelial barrier permeability of the treated cells were evaluated with CCK-8 assay and FITC-dextran permeability assay; the levels of intracellular reactive oxygen species (ROS) and localization and expression levels of the proteins related with barrier function and oxidative stress were detected using immunofluorescence staining, DCFH-DA probe and Western blotting. RESULTS: S1PR5 activation obviously enhanced viability of bEnd.3 cells exposed to OGD/R (P<0.0001). Both activation and overexpression of S1PR5 reduced FITC-dextran leakage, while S1PR5 knockdown significantly increased FITC-dextran leakage in the exposed bEnd.3 cells. Activation and overexpression of S1PR5 both increased the cellular expressions of the barrier proteins ZO-1 and occludin, while S1PR5 knockdown produced the opposite effect. In cells exposed to OGD/R, ROS production was significantly reduced by S1PR5 activation and overexpression but increased following S1PR5 knockdown. Overexpression of S1PR5 obviously increased the expressions of the antioxidant proteins Nrf2, HO-1 and SOD2 in the exposed cells. CONCLUSIONS S1PR5 activation and overexpression significantly improve cell viability and reduce permeability of a mouse brain microvascular endothelial cell model of OGD/R, the mechanism of which may involve the reduction in ROS production and upregulation of the antioxidant proteins.
Animals ; Mice ; Oxidative Stress ; Endothelial Cells/cytology* ; Brain/blood supply* ; Reactive Oxygen Species/metabolism* ; Receptors, Lysosphingolipid/metabolism* ; Sphingosine-1-Phosphate Receptors ; Blood-Brain Barrier/metabolism* ; Glucose ; Cell Line ; Oxygen/metabolism* ; NF-E2-Related Factor 2/metabolism*

OBJECTIVES: To investigate the effects of live combined Bacillus subtilis and Enterococcus faecium (LCBE) on glucose and lipid metabolism in mice with type 2 diabetes mellitus (T2DM) and circadian rhythm disorder (CRD) and explore the possible mechanisms. METHODS: KM mice were randomized into normal diet (ND) group (n=8), high-fat diet (HFD) group (n=8), and rhythm-intervention with HFD group (n=16). After 8 weeks of feeding, the mice were given an intraperitoneal injection of streptozotocin (100 mg/kg) to induce T2DM. The mice in CRD-T2DM group were further randomized into two equal groups for treatment with LCBE (225 mg/kg) or saline by gavage; the mice in ND and HFD groups also received saline gavage for 8 weeks. Blood glucose level of the mice was measured using a glucometer, and serum levels of Bmal1, PER2, insulin, C-peptide and lipids were determined with ELISA. Colon morphology and hepatic lipid metabolism of the mice were examined using HE staining and Oil Red O staining, respectively, and fecal short-chain fatty acids (SCFAs) was detected using LC-MS; GPR43 and GLP-1 expression levels were analyzed using RT-qPCR and Western blotting. RESULTS: Compared with those in CRD-T2DM group, the LCBE-treated mice exhibited significant body weight loss, lowered levels of PER2, insulin, C-peptide, total cholesterol (TC) and LDL-C, and increased levels of Bmal1 and HDL-C levels. LCBE treatment significantly increased SCFAs, upregulated GPR43 and GLP-1 expressions at both the mRNA and protein levels, and improved hepatic steatosis and colon histology. CONCLUSIONS LCBE ameliorates lipid metabolism disorder in CRD-T2DM mice by reducing body weight and improving lipid profiles and circadian regulators possibly via the SCFAs/GPR43/GLP-1 pathway.
Animals ; Mice ; Lipid Metabolism ; Diabetes Mellitus, Type 2/metabolism* ; Enterococcus faecium ; Glucagon-Like Peptide 1/metabolism* ; Bacillus subtilis ; Diabetes Mellitus, Experimental/metabolism* ; Circadian Rhythm ; Blood Glucose/metabolism* ; Receptors, G-Protein-Coupled/metabolism* ; Fatty Acids, Volatile/metabolism* ; Male ; Chronobiology Disorders/metabolism*

OBJECTIVES: To investigate the effects of Naoluo Xintong Decoction (NLXTD) on proliferation of rat brain microvascular endothelial cells (BMECs) after oxygen-glucose deprivation/reoxygenation (OGD/R) injury and role of the HIF-1α/VEGF pathway in mediating its effect. METHODS: Using a BMEC model of OGD/R, we tested the effects of 10% NLXTD-medicated rat serum, alone or in combination with 2ME2 or 10% NAKL, on cell proliferation, migration, tube-forming ability and permeability using CCK-8 assay, Transwell chamber assay, tube formation assay and permeability assay. Cellular expressions of VEGF and Notch were detected using ELISA and laser confocal immunofluorescence analysis, and the expressions of HIF-1α, VEGFR2, Notch1, ERK and P-ERK1/2 proteins were detected with Western blotting. RESULTS: OGD/R injury significantly decreased viability of BMECs. NLXTD treatment of the cells with OGD/R could significantly promoted cell proliferation, migration and tube formation ability, but these effects were strongly attenuated by application of 2ME2. NLXTD treatment also significantly increased the percentages of VEGF- and Notch-positive cells in the cell models and obviously enhanced the expression levels of HIF-1α, VEGFR2, Notch1 and P-ERK1/2. CONCLUSIONS NLXTD promotes proliferation, migration, and tube formation of rat BMECs after OGD/R injury possibly by activating the HIF-1α/VEGF signaling pathway.
Animals ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Vascular Endothelial Growth Factor A/metabolism* ; Endothelial Cells/metabolism* ; Rats ; Cell Proliferation/drug effects* ; Signal Transduction/drug effects* ; Glucose ; Brain/blood supply* ; Cells, Cultured ; Rats, Sprague-Dawley ; Vascular Endothelial Growth Factor Receptor-2/metabolism* ; Oxygen/metabolism* ; Cell Hypoxia

This study investigates the role of Interleukin 17 (IL-17) in exacerbating periapical lesions caused by Porphyromonas gingivalis (Pg) lipopolysaccharides (LPS) in the context of metabolic disease and its potential impact on glucose tolerance. Researchers developed a unique mouse model where mice were monocolonized with Pg to induce periapical lesions. After 1 month, they were fed a high-fat diet (HFD) for 2 months to simulate metabolic disease and oral microbiota dysbiosis. To explore the role of LPS from Pg, wild-type (WT) mice were challenged with purified LPS from Porphyromonas gingivalis, as well as with LPS-depleted and non-depleted Pg bacteria; IL-17 knockout (KO) mice were also included to assess the role of IL-17 signaling. The impact on bone lysis, periapical injury, glucose intolerance, and immune response was assessed. Results showed that in WT mice, the presence of LPS significantly worsened bone lysis, Th17 cell recruitment, and periapical injury. IL-17 KO mice exhibited reduced bone loss, glucose intolerance, and immune cell infiltration. Additionally, inflammatory markers in adipose tissue were lower in IL-17 KO mice, despite increased dysbiosis. The findings suggest that IL-17 plays a critical role in amplifying Pg-induced periapical lesions and systemic metabolic disturbances. Targeting IL-17 recruitment could offer a novel approach to improving glycemic control and reducing type 2 diabetes (T2D) risk in individuals with periapical disease.
Animals ; Porphyromonas gingivalis/immunology* ; Th17 Cells/immunology* ; Lipopolysaccharides/immunology* ; Mice ; Glucose Intolerance/microbiology* ; Interleukin-17/metabolism* ; Mice, Knockout ; Mice, Inbred C57BL ; Disease Models, Animal ; Diet, High-Fat ; Periapical Diseases/microbiology* ; Male ; Dysbiosis

Metabolic dysfunction-associated steatotic liver disease (MASLD) has become a global epidemic, yet effective pharmacological treatments remain limited. Secreted proteins play diverse roles in regulating glucose and lipid metabolism, and their dysregulation is implicated in the development of various metabolic diseases, including MASLD. Therefore, targeting secreted proteins and modulating associated signaling pathways represents a promising therapeutic strategy for MASLD. In this review, we summarize recent findings on the roles of emerging families of secreted proteins in MASLD and related metabolic disorders. These include the orosomucoid (ORM) family, secreted acidic cysteine rich glycoprotein (SPARC) family, neuregulin (Nrg) family, growth differentiation factor (GDF) family, interleukin (IL) family, fibroblast growth factor (FGF) family, bone morphogenic protein (BMP) family, as well as isthmin-1 (Ism1) and mesencephalic astrocyte-derived neurotrophic factor (MANF). The review highlights their impact on glucose and lipid metabolism and discusses the clinical potential of targeting these secreted proteins as a therapeutic approach for MASLD.
Humans ; Fatty Liver/pathology* ; Animals ; Lipid Metabolism ; Glucose/metabolism*

OBJECTIVE: To explore the effects and mechanisms of the C-X-C motif chemokine ligand 12/C-X-C motif chemokine receptor 4 (CXCL12/CXCR4) signaling axis on apoptosis and autophagy in SH-SY5Y neuronal cells subjected to oxygen-glucose deprivation/reperfusion (OGD/R) model in vitro. METHODS: SH-SY5Y cells were divided into the following groups: OGD/R group and non-OGD/R group, with the OGD/R group subjected to OGD/R modeling and the non-OGD/R group receiving no treatment. Cells were also divided into CXCL12⁺ and CXCL12^- groups; the CXCL12⁺ group received 0.1 mg/L exogenous recombinant CXCL12 (rhCXCL12) at reoxygenation, while the CXCL12^- group did not. Another set of cells was divided into CXCL12+AMD3100 and CXCL12 groups; the CXCL12+AMD3100 group was pretreated with 2.5 mg/L AMD3100, a CXCR4 inhibitor, for 2 hours before OGD/R and received both 2.5 mg/L AMD3100 and 0.1 mg/L rhCXCL12 at reoxygenation, whereas the CXCL12 group received rhCXCL12 only. Additionally, cells were divided into small interfering RNA CXCR4 (siCXCR4) and small interfering RNA negative control (siNC) groups; the siCXCR4 group underwent CXCR4 knockdown before OGD/R modeling and received 0.1 mg/L rhCXCL12 at reoxygenation, while the siNC group, transfected with a negative control, received the same treatment. Protein expression of autophagy-related 16 (ATG16), microtubule-associated protein 1 light chain 3 (LC3), aquaporin-3 (AQP3), and CXCR4 was detected by Western blotting. Apoptosis rate and CXCR4 expression were measured by flow cytometry. RESULTS: Compared with the non-OGD/R group, the OGD/R group showed a significantly increased apoptosis rate and markedly decreased protein expression levels of ATG16, LC3, AQP3, and CXCR4 (all P < 0.05). CXCR4 fluorescent expression was also significantly reduced, suggesting that OGD/R simultaneously affects neuronal apoptosis and autophagy while inhibiting CXCR4 and AQP3 expression in SH-SY5Y cells. Compared with the CXCL12^- group, the CXCL12⁺ group exhibited no significant change in apoptosis rate but demonstrated significantly increased protein expression of ATG16, LC3, and AQP3 (ATG16/GAPDH: 1.21±0.10 vs. 1.00±0.00; LC3/β-actin: 1.22±0.10 vs. 1.00±0.00; AQP3/β-actin: 1.26±0.04 vs. 1.00±0.00; all P < 0.05). CXCR4 expression was also significantly enhanced (fluorescence intensity: 1.19±0.05 vs. 1.00±0.00, P < 0.05), indicating that CXCL12 may promote autophagy in OGD/R-injured SH-SY5Y cells via the CXCR4/AQP3 pathway. Compared with the CXCL12 group, the CXCL12+AMD3100 group showed no significant difference in apoptosis rate but significantly lower protein levels of ATG16 and LC3 (ATG16/GAPDH: 0.75±0.08 vs. 1.00±0.00; LC3/GAPDH: 0.86±0.07 vs. 1.00±0.00; both P < 0.05), suggesting that CXCL12 induces autophagy in OGD/R SH-SY5Y cells through CXCR4. Compared with the siNC group, the siCXCR4 group showed no significant change in apoptosis rate but significantly reduced protein expression of ATG16, LC3, AQP3, and CXCR4 (ATG16/GAPDH: 0.76±0.06 vs. 1.00±0.00; LC3/GAPDH: 0.79±0.11 vs. 1.00±0.00; AQP3/GAPDH: 0.81±0.05 vs. 1.00±0.00; CXCR4/GAPDH: 0.86±0.04 vs. 1.00±0.00; all P < 0.05), indicating that CXCR4 knockdown suppresses OGD/R-induced autophagy in SH-SY5Y cells likely via AQP3. CONCLUSIONS The CXCL12/CXCR4 signaling axis can regulate OGD/R-induced autophagy in SH-SY5Y cells through AQP3 without affecting apoptosis, indicating a role for this pathway in neuronal autophagy during cerebral ischemia/reperfusion injury.
Humans ; Receptors, CXCR4/metabolism* ; Chemokine CXCL12/metabolism* ; Autophagy ; Glucose/metabolism* ; Apoptosis ; Neurons/cytology* ; Oxygen/metabolism* ; Signal Transduction ; Cell Line, Tumor ; Cell Hypoxia ; Benzylamines ; Cyclams