OBJECTIVE: To observe the effects of acupuncture on podocyte autophagy and long non-coding RNA SOX2 overlapping transcript (LncRNA SOX2OT)/mammalian target of rapamycin C1 (mTORC1)/Unc-51-like kinase 1 (ULK1) pathway in rats with diabetic kidney disease (DKD), and to explore the mechanism by which acupuncture reduces urinary protein. METHODS: A total of 40 SPF-grade male Sprague-Dawley rats were randomly divided into a control group (n=10) and a modeling group (n=30). The DKD model was established by feeding a high-fat, high-sugar diet combined with intraperitoneal injection of streptozotocin (STZ) in the modeling group. Twenty rats with successful DKD model were randomly divided into a model group (n=10) and an acupuncture group (n=10). The acupuncture group received "spleen and stomach-regulating" acupuncture at bilateral "Zusanli" (ST36), "Fenglong" (ST40), "Yinlingquan" (SP9), and "Zhongwan" (CV12), 30 min per session, once daily, five times per week, for four weeks. The general condition, fasting blood glucose (FBG), 2-hour postprandial glucose (2hPG), serum creatinine (SCr), blood urea nitrogen (BUN), 24-hour urinary protein quantification, and urine albumin-to-creatinine ratio (UACR) were compared before and after the intervention. After intervention, urinary podocyte injury marker SPON2 was measured by ELISA. Podocyte autophagosomes and glomerular basement membrane ultrastructure in renal tissue were observed via transmission electron microscopy. Podocyte apoptosis was assessed by TUNEL staining. The protein expression of microtubule-associated protein 1 light chain 3Ⅱ (LC3-Ⅱ), mTORC1, ULK1, Beclin-1, and p62 in renal tissue was detected by Western blot. LncRNA SOX2OT expression in renal tissue was measured by real-time PCR. RESULTS: After the intervention, compared with the control group, the model group exhibited increased food and water intake, increased urine output, weight loss, and loose stools; compared with the model group, the food and water intake, urine volume, and loose stools were improved in the acupuncture group. Compared with the control group, FBG, 2hPG, SCr, BUN, 24-hour urinary protein quantification, UACR, and urinary SPON2 were all higher in the model group (P<0.01); compared with the model group, the FBG, 2hPG, SCr, BUN, 24-hour urinary protein quantification, UACR, and urinary SPON2 were all lower in the acupuncture group (P<0.01). Compared with the control group, the model group showed reduced podocyte autophagosomes and thickened glomerular basement membrane; compared with the model group, the acupuncture group had increased podocyte autophagosomes and less thickened basement membrane. Compared with the control group, the podocyte apoptosis index (AI) was higher in the model group (P<0.01); compared with the model group, the AI was lower in the acupuncture group (P<0.01). Compared with the control group, the expression of ULK1, Beclin-1, and LC3-Ⅱ proteins was lower, and the expression of mTORC1 and p62 proteins was higher in the model group (P<0.01). Compared with the model group, the expression of ULK1, Beclin-1, and LC3-Ⅱ proteins was higher, and the expression of mTORC1 and p62 proteins was lower in the acupuncture group (P<0.01). Compared with the control group, the LncRNA SOX2OT expression was lower in the model group (P<0.01). Compared with the model group, LncRNA SOX2OT expression was higher in the acupuncture group (P<0.01). CONCLUSION The "spleen and stomach-regulating" acupuncture method could improve renal function in DKD rats, reduce blood glucose and urinary protein excretion, alleviate podocyte injury, and enhance podocyte autophagy. The mechanism may be related to modulation of the renal LncRNA SOX2OT/mTORC1/ULK1 pathway.
Animals ; Podocytes/cytology* ; Diabetic Nephropathies/physiopathology* ; Rats, Sprague-Dawley ; Male ; Rats ; Mechanistic Target of Rapamycin Complex 1/genetics* ; Autophagy ; Acupuncture Therapy ; Autophagy-Related Protein-1 Homolog/genetics* ; RNA, Long Noncoding/metabolism* ; Humans ; Signal Transduction

This study aimed to investigate the effect of saltwater stir-fried Plantaginis Semen(SPS) on renal fibrosis in rats and decipher the underlying mechanism. Thirty-six Sprague-Dawley rats were randomly assigned into control, model, losartan potassium, and low-, medium-, and high-dose(15, 30, and 60 g·kg~(-1), respectively) SPS groups. Rats in other groups except the control group were subjected to unilateral ureteral obstruction(UUO) to induce renal fibrosis, and the modeling and gavage lasted for 14 days. After 14 consecutive days of treatment, the levels of serum creatinine(Scr) and blood urea nitrogen(BUN) in rats of each group were determined by an automatic biochemical analyzer. Hematoxylin-eosin(HE) and Masson staining were used to evaluate pathological changes in the renal tissue. Western blot and immunofluorescence assay were conducted to determine the protein levels of fibronectin(FN), collagen Ⅰ, vimentin, and α-smooth muscle actin(α-SMA) in the renal tissue. The mRNA levels of epithelial-mesenchymal transition(EMT)-associated transcription factors including twist family bHLH transcription factor 1(TWIST1), snail family transcriptional repressor 1(SNAI1), and zinc finger E-box binding homeobox 1(ZEB1), as well as inflammatory cytokines such as interleukin-1β(IL-1β), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α), were determined by RT-qPCR. Human renal proximal tubular epithelial(HK2) cells exposed to transforming growth factor-β(TGF-β) for the modeling of renal fibrosis were used to investigate the inhibitory effect of SPS on EMT. Network pharmacology and Western blot were employed to explore the molecular mechanism of SPS in alleviating renal fibrosis. The results showed that SPS significantly reduced Scr and BUN levels and alleviated renal injury and collagen deposition in UUO rats. Moreover, SPS notably down-regulated the protein levels of FN, collagen Ⅰ, vimentin, and α-SMA as well as the mRNA levels of SNAI1, ZEB1, TWIST1, IL-1β, IL-6, and TNF-α in the kidneys of UUO rats and TGF-β-treated HK-2 cells. In addition, compared with Plantaginis Semen without stir-frying with saltwater, SPS showed increased content of specific compounds, which were mainly enriched in the mitogen-activated protein kinase(MAPK) signaling pathway. SPS significantly inhibited the phosphorylation of extracellular signal-regulated kinase(ERK) and p38 MAPK in the kidneys of UUO rats and TGF-β-treated HK2 cells. In conclusion, SPS can alleviate renal fibrosis by attenuating EMT through inhibition of the MAPK signaling pathway.
Animals ; Epithelial-Mesenchymal Transition/drug effects* ; Rats, Sprague-Dawley ; Male ; Rats ; Fibrosis/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Kidney Diseases/pathology* ; Kidney Tubules/pathology* ; Humans

Objective To investigate the impact of Qizhi Jiangtang Capsule (QZJT) on renal damage in diabetic nephropathy (DN) mice via NOD like receptors family pyrin domain containing 3/caspase-1/ Gasdermin D (NLRP3/caspase-1/GSDMD) signaling pathway. Methods Mice were randomly allocated into six experimental groups: a normal control group (NC), a diabetic nephropathy model group (DN), a low-dose QZJT treatment group (L-QZJT), a high-dose QZJT treatment group (H-QZJT), a positive control group administered Shenqi Jiangtang Granules (SQJT), and an ML385 group (treated with an inhibitor of nuclear factor erythroid 2-related factor 2, Nrf2). Upon successful model induction, therapeutic interventions were commenced. Renal function impairment in the mice was evaluated through quantification of fasting blood glucose (FBG), 24-hour urinary albumin (UAlb), serum creatinine (SCr), blood urea nitrogen (BUN), and the kidney-to-body mass ratio (K/B). Renal tissue pathology was evaluated using HE and PAS staining. Serum levels of inflammatory cytokines IL-1β and IL-18 were quantified by ELISA. Levels of podocyte markers and proteins involved in relevant pathways were assessed using Western blot analysis. Results Compared with the NC group, FBG, 24 h UAlb, SCr, and BUN were increased in the DN group, and the K/B mass ratio was also increased. In contrast, compared with the DN group, FBG, 24 h UAlb, SCr, and BUN in both the low-dose (L-QZJT) and high-dose Quanzhou Jintang (H-QZJT) groups were decreased, and the K/B mass ratio was decreased as well. The therapeutic efficacy of H-QZJT was comparable to that of Shenqi Jiangtang Granules. QZJT ameliorated renal histopathological injury in DN mouse, increased the protein levels of Nephrin (a podocyte marker), and decreased the protein levels of NLRP3, apoptosis-associated speck-like protein containing CARD (ASC), pro-caspase-1, and GSDMD-N. After ML385 treatment, renal cells exhibited swelling and morphological changes, the inflammatory infiltrate area was enlarged, the protein levels of NLRP3, ASC, pro-caspase-1, and GSDMD-N were up-regulated, and the levels of IL-1β and IL-18 were increased. Conclusion QZJT may inhibit podocyte pyroptosis by acting on the Nrf2 to regulate the NLRP3/caspase-1/GSDMD pathway, thus improving renal damage in DN mouse.
Animals ; Diabetic Nephropathies/pathology* ; Podocytes/pathology* ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics* ; Pyroptosis/drug effects* ; Drugs, Chinese Herbal/administration & dosage* ; Caspase 1/genetics* ; Signal Transduction/drug effects* ; Mice ; Phosphate-Binding Proteins/genetics* ; Male ; Intracellular Signaling Peptides and Proteins/metabolism* ; Mice, Inbred C57BL ; Kidney/pathology* ; Gasdermins

Objective To investigate the effects of exosomes (Exo) derived from high glucose-stimulated glomerular mesangial cells (GMC) on the kidneys of C57BL/6 mice and the intervention mechanism of Tongluo Yishen Formula (TLYSF). Methods The rat GMC were divided into a normal glucose group (NG, with 5.6 mmol/L glucose) and a high glucose group (HG, with 30 mmol/L glucose). After 24 hours of culture, the supernatant was collected, and exosomes were extracted using the ultracentrifugation method. The exosomes were then identified by transmission electron microscopy and Western blot analysis. Male C57BL/6 mice were divided into three groups: NO-Exo group, NG-Exo group, and HG-Exo group. These groups were respectively administered tail vein injections of PBS buffer, exosomes derived from GMC cultured in normal glucose, and exosomes derived from GMC cultured in high glucose, three times a week for a total of 8 weeks. After 8 weeks, the mice in the HG-Exo group were randomly divided into three subgroups: the HG-Exo group [gavaged with saline], the HG-Exo+TLYSF group [gavaged with TLYSF at 34.32 g/(kg.d)], and the HG-Exo + VAL group [gavaged with valsartan suspension at 10.4 mg/(kg.d)], and the intervention lasted for 4 weeks. Urinary microalbumin (mALb), urinary N-acetyl-β-D-aminoglucosidase (NAG), glycated hemoglobin (HbA1c), serum creatinine (Scr) and urea nitrogen (BUN) were detected. Transmission electron microscopy was used to observe the ultrastructure of renal tissues. TUNEL was used to detect the DNA damage of renal tissue cells. Immunofluorescence was used to detect the expression of NOD-like receptor family pyrin domain containing 3 (NLRP3) and wilms tumor 1(WT-1). RT-PCR was used to detect the mRNA levels of NLRP3, cysteinyl aspartate-specific proteinase 1 (caspase-1), interleukin-1 beta (IL-1β), miR-200c-3p and miR-148a-3p. Western Blot was employed to detect the protein expression of NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), caspase-1 and IL-1β. Results Compared with the NG-Exo group, mice in the HG-Exo group exhibited significantly increased levels of mALb, urinary NAG, Scr and BUN. Transmission electron microscopy revealed ruptured podocyte membranes and swollen mitochondria. The positive rate of cells stained by the TUNEL increased, with elevated optical density of NLRP3 and decreased optical density of WT-1. Additionally, there was a significant increase in the level of NLRP3, caspase-1, IL-1β mRNA, as well as miR-200c-3p and miR-148a-3p. The protein expression of NLRP3, ASC, caspase-1, and IL-1β also increased. Compared with HG-Exo group, mice in the HG-Exo+TLYSF group showed decreased levels of mALb, urinary NAG, Scr, and BUN. The podocyte membranes were relatively intact, and mitochondrial damage was alleviated. The positive rate of cells stained by the TUNEL decreased, along with a reduction in the optical density of NLRP3 and an increase in the optical density of WT-1. Furthermore, the mRNA expression levels of NLRP3, caspase-1, IL-1β, miR-200c-3p, and miR-148a-3p were all downregulated to varying degrees. The protein expression levels of NLRP3, ASC, caspase-1, and IL-1β also decreased. Conclusion Exosomes derived from GMC stimulated by high glucose can damage the kidneys of mice and induce podocyte pyroptosis. TLYSF may ameliorate podocyte pyroptosis by downregulating the expression of exosomal miR-200c-3p and miR-148a-3p and inhibiting the activation of the NLRP3/ASC/caspase-1 pathway.
Animals ; Exosomes/ultrastructure* ; Glucose/pharmacology* ; Male ; Podocytes/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Mice, Inbred C57BL ; Mice ; Mesangial Cells/metabolism* ; Pyroptosis/drug effects* ; Rats ; MicroRNAs/genetics*

Tubulointerstitial fibrosis (TIF) is one of the key indicators in evaluating the renal function of patients. Mild TIF can cause a vicious cycle of renal tubular glomerular injury and aggravate renal disease. Therefore, studying the mechanisms underlying TIF is essential to identify therapeutic targets, thereby protecting the renal function of patients with timely intervention. Astragaloside IV (AS-IV) is a Chinese medicine component that has been shown to inhibit the occurrence and progression of TIF via multiple pathways. Previous studies have reported that AS-IV protected against TIF by inhibiting inflammation, autophagy, endoplasmic reticulum stress, macrophages, and transforming growth factor-β1, which laid the foundation for the development of a new preventive and therapeutic option for TIF.
Saponins/pharmacology* ; Triterpenes/pharmacology* ; Humans ; Fibrosis ; Animals ; Kidney Tubules/drug effects* ; Kidney Diseases/pathology*

OBJECTIVE: To investigate the effects of astragaloside IV (AS-IV) on podocyte injury of diabetic nephropathy (DN) and reveal its potential mechanism. METHODS: In in vitro experiment, podocytes were divided into 4 groups, normal, high glucose (HG), inositol-requiring enzyme 1 (IRE-1) α activator (HG+thapsigargin 1 µmol/L), and IRE-1α inhibitor (HG+STF-083010, 20 µmol/L) groups. Additionally, podocytes were divided into 4 groups, including normal, HG, AS-IV (HG+AS-IV 20 µmol/L), and IRE-1α inhibitor (HG+STF-083010, 20 µmol/L) groups, respectively. After 24 h treatment, the morphology of podocytes and endoplasmic reticulum (ER) was observed by electron microscopy. The expressions of glucose-regulated protein 78 (GRP78) and IRE-1α were detected by cellular immunofluorescence. In in vivo experiment, DN rat model was established via a consecutive 3-day intraperitoneal streptozotocin (STZ) injections. A total of 40 rats were assigned into the normal, DN, AS-IV [AS-IV 40 mg/(kg·d)], and IRE-1α inhibitor [STF-083010, 10 mg/(kg·d)] groups (n=10), respectively. The general condition, 24-h urine volume, random blood glucose, urinary protein excretion rate (UAER), urea nitrogen (BUN), and serum creatinine (SCr) levels of rats were measured after 8 weeks of intervention. Pathological changes in the renal tissue were observed by hematoxylin and eosin (HE) staining. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were used to detect the expressions of GRP78, IRE-1α, nuclear factor kappa Bp65 (NF-κBp65), interleukin (IL)-1β, NLR family pyrin domain containing 3 (NLRP3), caspase-1, gasdermin D-N (GSDMD-N), and nephrin at the mRNA and protein levels in vivo and in vitro, respectively. RESULTS: Cytoplasmic vacuolation and ER swelling were observed in the HG and IRE-1α activator groups. Podocyte morphology and ER expansion were improved in AS-IV and IRE-1α inhibitor groups compared with HG group. Cellular immunofluorescence showed that compared with the normal group, the fluorescence intensity of GRP78 and IRE-1α in the HG and IRE-1α activator groups were significantly increased whereas decreased in AS-IV and IRE-1α inhibitor groups (P<0.05). Compared with the normal group, the mRNA and protein expressions of GRP78, IRE-1α, NF-κ Bp65, IL-1β, NLRP3, caspase-1 and GSDMD-N in the HG group was increased (P<0.05). Compared with HG group, the expression of above indices was decreased in the AS-IV and IRE-1α inhibitor groups, and the expression in the IRE-1α activator group was increased (P<0.05). The expression of nephrin was decreased in the HG group, and increased in AS-IV and IRE-1α inhibitor groups (P<0.05). The in vivo experiment results revealed that compared to the normal group, the levels of blood glucose, triglyceride, total cholesterol, BUN, blood creatinine and urinary protein in the DN group were higher (P<0.05). Compared with DN group, the above indices in AS-IV and IRE-1α inhibitor groups were decreased (P<0.05). HE staining revealed glomerular hypertrophy, mesangial widening and mesangial cell proliferation in the renal tissue of the DN group. Compared with the DN group, the above pathological changes in renal tissue of AS-IV and IRE-1α inhibitor groups were alleviated. Quantitative RT-PCR and Western blot results of GRP78, IRE-1α, NF-κ Bp65, IL-1β, NLRP3, caspase-1 and GSDMD-N were consistent with immunofluorescence analysis. CONCLUSION AS-IV could reduce ERS and inflammation, improve podocyte pyroptosis, thus exerting a podocyte-protective effect in DN, through regulating IRE-1α/NF-κ B/NLRP3 signaling pathway.
Podocytes/metabolism* ; Animals ; Diabetic Nephropathies/metabolism* ; Saponins/therapeutic use* ; Triterpenes/therapeutic use* ; Signal Transduction/drug effects* ; NF-kappa B/metabolism* ; Protein Serine-Threonine Kinases/metabolism* ; Male ; Rats, Sprague-Dawley ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Endoribonucleases/metabolism* ; Endoplasmic Reticulum Chaperone BiP ; Rats ; Diabetes Mellitus, Experimental/complications* ; Endoplasmic Reticulum/metabolism* ; Multienzyme Complexes

OBJECTIVE: To identify the underlying molecular mechanism of Modified Hu-Lu-Ba-Wan (MHW) in alleviating renal lesions in mice with diabetic kidney disease (DKD). METHODS: The db/db mice were divided into model group and MHW group according to a random number table, while db/m mice were settled as the control group (n=8 per group). The control and model groups were gavaged daily with distilled water [10 mL/(kg·d)], and the MHW group was treated with MHW [17.8 g/(kg·d)] for 6 weeks. After MHW administration for 6 weeks, indicators associated with glucolipid metabolism and urinary albumin were tested. Podocytes were observed by transmission electron microscopy. Kidney transcriptomics was performed after confirming therapeutic effects of MHW on DKD mice. The relevant target of MHW' effect in DKD was further determined by enzyme-linked immunosorbent assay, Western blot analysis, immunohistochemistry, and immunofluorescence staining. RESULTS: Compared with the model group, MHW improved glucose and lipid metabolism (P<0.05), and reduced lipid deposition in the kidney. Meanwhile, MHW reduced the excretion of urinary albumin (P<0.05) and ameliorated renal damage. Transcriptomic analysis revealed that the inflammation response, particularly the interleukin-17 (IL-17) signaling pathway, may be responsible for the effect of MHW on DKD. Furtherly, our results found that MHW inhibited IL-17A and alleviated early fibrosis in the diabetic kidney. CONCLUSION MHW ameliorated renal damage in DKD via inhibiting IL-17A, suggesting a potential strategy for DKD therapy.
Animals ; Diabetic Nephropathies/genetics* ; Interleukin-17/antagonists & inhibitors* ; Drugs, Chinese Herbal/therapeutic use* ; Male ; Kidney/ultrastructure* ; Podocytes/metabolism* ; Mice ; Albuminuria ; Lipid Metabolism/drug effects* ; Mice, Inbred C57BL

OBJECTIVES: Pyroptosis plays a critical role in tubulointerstitial lesions of diabetic kidney disease (DKD). Annexin A2 (ANXA2) is involved in cell proliferation, apoptosis, and adhesion and may be closely related to DKD, but its specific mechanism remains unclear. This study aims to investigate the role and molecular mechanism of ANXA2 in high glucose-induced pyroptosis of renal tubular epithelial cells, providing new targets for DKD prevention and treatment. METHODS: Human renal tubular epithelial HK-2 cells were divided into a normal glucose group (5.5 mmol/L), a high glucose group (30.0 mmol/L), and a osmotic control group (24.5 mmol/L mannitol+5.5 mmol/L glucose). ANXA2 expression was modulated by overexpression of plasmids and small interfering RNA (siRNA). Cell proliferation was measured by 5-ethynyl-2'-deoxyuridine (EdU) assay, apoptosis by flow cytometry, and ANXA2, p50, and p65 subcellular localization by immunofluorescence. Western blotting was employed to detect α-smooth muscle actin (α-SMA), fibronectin (FN), and collagen type IV (Col-IV). Real-time fluorescence quantitative PCR (RT-qPCR) and Western blotting were used to analyze nuclear factor-κB (NF-κB) subunits p50/p65 and the pyroptosis pathway factors NLR family Pyrin domain containing 3 (NLRP3), caspase-1, inferleukin (IL)-1β, and IL-18. Protein interactions between ANXA2 and p50/p65 were examined by co-immunoprecipitation, while chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays were used to examine NF-κB binding to the ANXA2 promoter. RESULTS: High glucose upregulated ANXA2 expression and promoted its nuclear translocation (P<0.01). High glucose reduced cell proliferation, increased apoptosis, and elevated α-SMA, FN, and Col-IV expression (all P<0.05); ANXA2 overexpression aggravated these effects (all P<0.05), while ANXA2 knockdown reversed them (all P<0.05). High glucose activated NF-κB and increased NLRP3, caspase-1, L-1β, and IL-18 mRNA and protein expression (all P<0.05); ANXA2 overexpression further enhanced this, whereas knockdown suppressed NF-κB activation and downstream factors (all P<0.05). Co-immunoprecipitation confirmed ANXA2 directly binds the NF-κB subunit p65. ChIP assays revealed p65 binds specifically to ANXA2 promoter regions (ChIP-2, ChIP-4, and ChIP-6), and luciferase activity in corresponding mutant constructs (M2, M4, and M6) was significantly increased versus controls (all P<0.05), confirming positive transcriptional regulation of ANXA2 by p65. CONCLUSIONS ANXA2 and NF-κB form a positive feedback loop that sustains NLRP3 inflammasome activation, promotes pyroptosis pathway activation, and aggravates high glucose-induced renal tubular epithelial cell injury. Targeting ANXA2 or blocking its interaction with p65 may be a novel strategy to slow DKD progression.
Humans ; Pyroptosis/drug effects* ; Annexin A2/physiology* ; Epithelial Cells/cytology* ; Kidney Tubules/cytology* ; Glucose/pharmacology* ; Diabetic Nephropathies/metabolism* ; NF-kappa B/metabolism* ; Cell Line ; Cell Proliferation ; Transcription Factor RelA/metabolism* ; Feedback, Physiological

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