ABSTRACT
Tubulointerstitial fibrosis (TIF) plays a crucial role in the progression of diabetic kidney disease (DKD). However, the underlying molecular mechanisms remain obscure. The present study aimed to examine whether transmembrane member 16A (TMEM16A), a Ca2+-activated chloride channel, contributes to the development of TIF in DKD. Interestingly, we found that TMEM16A expression was significantly up-regulated in tubule of murine model of DKD, which was associated with development of TIF. In vivo inhibition of TMEM16A channel activity with specific inhibitors Ani9 effectively protects against TIF. Then, we found that TMEM16A activation induces tubular mitochondrial dysfunction in in vivo and in vitro models, with the evidence of the TMEM16A inhibition with specific inhibitor. Mechanically, TMEM16A mediated tubular mitochondrial dysfunction through inhibiting PGC-1α, whereas overexpression of PGC-1α could rescue the changes. In addition, TMEM16A-induced fibrogenesis was dependent on increased intracellular Cl-, and reducing intracellular Cl- significantly blunted high glucose-induced PGC-1α and profibrotic factors expression. Taken together, our studies demonstrated that tubular TMEM16A promotes TIF by suppressing PGC-1α-mediated mitochondrial homeostasis in DKD. Blockade of TMEM16A may serve as a novel therapeutic approach to ameliorate TIF.
Subject(s)
Diabetes Mellitus , Diabetic Nephropathies , Animals , Mice , Diabetic Nephropathies/genetics , Homeostasis , Mitochondria , FibrosisABSTRACT
Podocyte injury is a characteristic pathological hallmark of diabetic nephropathy (DN). However, the exact mechanism of podocyte injury in DN is incompletely understood. This study was conducted using db/db mice and immortalized mouse podocytes. High-throughput sequencing was used to identify the differentially expressed long noncoding RNAs in kidney of db/db mice. The lentiviral shRNA directed against long noncoding RNA small nucleolar RNA host gene 5 (SNHG5) or microRNA-26a-5p (miR-26a-5p) agomir was used to treat db/db mice to regulate the SNHG5/miR-26a-5p pathway. Here, we found that the expression of transient receptor potential canonical type 6 (TRPC6) was significantly increased in injured podocytes under the condition of DN, which was associated with markedly decreased miR-26a-5p. We determined that miR-26a-5p overexpression ameliorated podocyte injury in DN via binding to 3'-UTR of Trpc6, as evidenced by the markedly reduced activity of luciferase reporters by miR-26a-5p mimic. Then, the upregulated SNHG5 in podocytes and kidney in DN was identified, and it was proved to sponge to miR-26a-5p directly using luciferase activity, RNA immunoprecipitation, and RNA pull-down assay. Knockdown of SNHG5 attenuated podocyte injury in vitro, accompanied by an increased expression of miR-26a-5p and decreased expression of TRPC6, demonstrating that SNHG5 promoted podocyte injury by controlling the miR-26a-5p/TRPC6 pathway. Moreover, knockdown of SNHG5 protects against podocyte injury and progression of DN in vivo. In conclusion, SNHG5 promotes podocyte injury via the miR-26a-5p/TRPC6 pathway in DN. Our findings provide novel insights into the pathophysiology of podocyte injury and a potential new therapeutic strategy for DN.
Subject(s)
Diabetes Mellitus , Diabetic Nephropathies , MicroRNAs , Podocytes , RNA, Long Noncoding , Mice , Animals , MicroRNAs/genetics , MicroRNAs/metabolism , Diabetic Nephropathies/metabolism , TRPC6 Cation Channel/genetics , TRPC6 Cation Channel/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Podocytes/metabolism , Apoptosis/genetics , Diabetes Mellitus/metabolismABSTRACT
Objective This study aimed to investigate the role of zinc sulphate in immune regulation in Artemisia annua pollen-challenged P815 mastocytoma cells. Methods P815 mastocytoma cells were treated with various concentrations of zinc sulphate and Artemisia annua pollen. Cell proliferation was measured using the Cell Counting Kit-8. The amount of ST2 and p38 in the cells were measured using Western blotting. The level of interleukins (IL)-33 in the supernatant was determined using the enzyme-linked immunosorbent assay. The levels of IL-2, IL-4, IL-5, interferon-γ, and tumor necrosis factor were measured using the cytometric bead array. Results Artemisia annua pollen at a concentration >0.001 µg/mL induced allergic response in the P815 mastocytoma cells. Expressions of IL-33, IL-4, ST2, and p38 increased along with higher concentrations of Artemisia annua pollen. Zinc sulphate of 50-200 µmol/L promoted the proliferation of P815 mastocytoma cells. Zinc sulphate attenuated the upregulation of IL-33, IL-4, ST2, and p38 caused by Artemisia annua pollen. Conclusion Zinc sulphate can promote the proliferation of P815 mastocytoma cells. It can also attenuate allergic response in the P815 mastocytoma cells induced by Artemisia annua pollen, which might provide a new treatment method for allergic diseases.
Subject(s)
Artemisia annua/adverse effects , Immunization , Immunomodulation/drug effects , Pollen/immunology , Zinc Sulfate/pharmacology , Biomarkers , Cell Line, Tumor , Cytokines/metabolism , Humans , Mastocytoma/immunology , Mastocytoma/metabolismABSTRACT
OBJECTIVE: We investigated the correlation between the expression of IL-17A in nasopharyngeal carcinoma tissues and cells and the occurrence and development of NPC was also investigated. METHODS: Forty-five NPC biopsy specimens from January 2014 to January 2016 were selected. Forty-five NPC tissue specimens and 45 chronic nasopharyngitis tissue samples were detected by immunohistochemistry. Statistical methods were used to analyze the correlation between IL-17A expression and the clinicopathological variables of NPC. The NPC patients were followed up. The levels of IL-17A mRNA in 40 NPC tissue specimens and 45 chronic nasopharyngitis tissue samples were detected by real-time PCR. IL-17A expression in 15 NPC tissue specimens and chronic nasopharyngitis tissue samples was further detected by Western blotting assays. RESULTS: IL-17A expression in NPC tissues was significantly higher than that of chronic nasopharyngitis tissues (P < 0.05). IL-17A was expressed in the nucleus and cytoplasm of both NPC tissues and chronic nasopharyngitis tissues. Stage III + IV NPC, tumor volume ≥ 50 mm, and hepatic envelope invasion and cervical lymph node metastasis were associated with significantly higher IL-17A levels versus stage I + II NPC, tumor size < 50 mm, no membrane invasion and lack of cervical lymph node metastasis (P < 0.05). IL-17A was statistically associated with tissue differentiation, serum EBV-lgA levels, and EBV infection. IL-17A-positive patients had significantly longer median survival versus IL-17A-negative patients (21.0 vs. 13.0 months, log-rank test: P < 0.05). Furthermore, 65% (26/40) of NPC tissue samples had significantly higher IL-17A mRNA levels than chronic nasopharyngitis (P < 0.05). IL-17A expression was significantly higher in NPC ≥ 50 mm, stage III + IV NPC and NPC with cervical lymph node invasion than its corresponding chronic nasopharyngitis tissue. CONCLUSION: IL-17A may be involved in the regulation of various malignant biological behaviors of NPC, which is closely related to the occurrence and development of NPC.
Subject(s)
Epstein-Barr Virus Infections/immunology , Interleukin-17/metabolism , Lymph Nodes , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms , Adult , Correlation of Data , Female , Humans , Immunohistochemistry , Lymph Nodes/immunology , Lymph Nodes/pathology , Lymphatic Metastasis , Male , Middle Aged , Nasopharyngeal Carcinoma/immunology , Nasopharyngeal Carcinoma/pathology , Nasopharyngeal Neoplasms/immunology , Nasopharyngeal Neoplasms/pathology , Nasopharyngitis/immunology , Neoplasm StagingABSTRACT
BACKGROUND/AIMS: The objective of this study was to investigate the potential role of IL-17 in the development of nasopharyngeal carcinoma (NPC) and to screen microRNAs (miRNAs) that potentially target IL-17 in NPC cells. METHODS: Blood was collected from NPC patients and normal subjects, and plasma IL-17 concentration was quantified by enzyme-linked immunosorbent assay. An immortalized normal human nasopharyngeal epithelial cell line, NP69, was treated with or without human IL-17 (15 ng/mL) for various times, and expression of IL-1ß, IL-6, IL-12, and TNF-α mRNA was assessed by real-time reverse transcription PCR. The candidate miRNAs that potentially target IL-17 were predicted by a bioinformatics strategy. The selected miR-135a mimic was transfected into primary NPC cells, and cell proliferation was assessed by MTT assay. RESULTS: The concentration of plasma IL-17 was significantly higher in the NPC patients (92.5 ± 7.3 pg/mL) than in the control subjects (56.8 ± 2.9 pg/mL). In response to IL-17 treatment, the mRNA expression of IL-1ß and IL-6 was significantly upregulated and reached a peak at 12 h, followed by a slight decrease at 24 h, while the mRNA expression of IL-12 and TNF-α was significantly upregulated at 12 h and remained high even at 48 h after exposure to IL-17. Moreover, miR-135a specifically targets IL-17 and was dramatically downregulated in NPC cells compared with NP69 cells. Transfection of exogenous miR-135a mimic resulted in significant suppression of IL-17 secretion and subsequent inhibition of NPC cell proliferation. CONCLUSIONS: Blood IL-17 was significantly higher in NPC patients compared with normal subjects. Expression of miR-135a in the cancer cells isolated from nasopharyngeal tumors was significantly lower than that in NP69 cells, and suppression of IL-17 by miR-135a mimic resulted in significant inhibition of NPC cell proliferation. These findings suggested that downregulation of miR-135a may contribute to the development of NPC via the mechanism of IL-17 stimulation of proinflammatory cytokine expression.
Subject(s)
Carcinoma/genetics , Gene Expression Regulation, Neoplastic , Interleukin-17/genetics , MicroRNAs/genetics , Nasopharyngeal Neoplasms/genetics , Carcinoma/blood , Cell Proliferation , Down-Regulation , Female , Humans , Interleukin-17/blood , Male , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/blood , Tumor Cells, CulturedABSTRACT
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the deposition of ß-amyloid (Aß) plaques and neurofibrillary tangles composed of tau protein in the brain. These neuropathological hallmarks contribute to cognitive impairment by inducing neuronal loss in the cerebral cortex and hippocampus. Unfortunately, current therapeutic approaches only target symptomatic relief and do not impede disease progression. Nicotinamide mononucleotide (NMN), a precursor of nicotinamide adenine dinucleotide (NAD+), has emerged as a promising candidate for the treatment of age-related neurodegenerative disorders. NMN supplementation could restore NAD+ levels, thereby alleviating neuronal damage and slowing the progression of AD and other aging-associated diseases. AD is closely associated with autophagic impairment and oxidative stress. Our in vivo experiments demonstrated that NMN could ameliorate pathological and behavioral impairments in AD mice. Specifically, NMN enhanced autophagy and promoted p-tau clearance. Meanwhile, NMN could activate the Nrf2/Keap1/NQO1 pathway, thereby reducing the oxidative stress. Immunofluorescence results demonstrated that NMN could alleviate neuronal damage in AD mice. Furthermore, in vitro results showed that the p-tau clearance and antioxidant stress effects of NMN were suppressed by autophagy inhibitor, chloroquine (CQ) or bafilomycin A1 (BafA1), in Aß-induced PC12 cells. Lastly, when Nrf2 was knocked down, the antioxidant stress, autophagy enhancement, and p-tau clearance effects of NMN were all inhibited. In conclusion, our research indicates that NMN exerts therapeutic effect against AD by activating autophagy and the Nrf2/Keap1/NQO1 pathway through a mutual regulating mechanism of autophagy and antioxidative stress. These findings highlight the promising potential of NMN for the treatment of AD.
Subject(s)
Alzheimer Disease , Autophagy , NF-E2-Related Factor 2 , Nicotinamide Mononucleotide , Oxidative Stress , Animals , Oxidative Stress/drug effects , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Autophagy/drug effects , Nicotinamide Mononucleotide/pharmacology , Nicotinamide Mononucleotide/therapeutic use , Mice , NF-E2-Related Factor 2/metabolism , Antioxidants/pharmacology , Antioxidants/therapeutic use , tau Proteins/metabolism , Kelch-Like ECH-Associated Protein 1/metabolism , Mice, Transgenic , Male , Disease Models, Animal , NAD(P)H Dehydrogenase (Quinone)/metabolism , PC12 Cells , Rats , Amyloid beta-Peptides/metabolism , Mice, Inbred C57BL , Signal Transduction/drug effectsABSTRACT
BACKGROUND: Tubulointerstitial fibrosis plays an important role in the progression of diabetic kidney disease (DKD). Sacubitril/valsartan (Sac/Val) exerts a robust beneficial effect in DKD. However, the potential functional effect of Sac/Val on tubulointerstitial fibrosis in DKD is still largely unclear. METHODS: Streptozotocin-induced diabetic mice were given Sac/Val or Val by intragastric administration once a day for 12 weeks. The renal function, the pathological changes of tubule injury and tubulointerstitial fibrosis, as well as mitochondrial morphology of renal tubules in mice, were evaluated. Genome-wide gene expression analysis was performed to identify the potential mechanisms. Meanwhile, human tubular epithelial cells (HK-2) were cultured in high glucose condition containing LBQ657/valsartan (LBQ/Val). Further, mitochondrial functions and Sirt1/PGC1α pathway of tubular epithelial cells were assessed by Western blot, Real-time-PCR, JC-1, MitoSOX or MitoTracker. Finally, the Sirt1 specific inhibitor, EX527, was used to explore the potential effects of Sirt1 signaling in vivo and in vitro. RESULTS: We found that Sac/Val significantly ameliorated the decline of renal function and tubulointerstitial fibrosis in DKD mice. The enrichment analysis of gene expression indicated metabolism as an important modulator in DKD mice with Sac/Val administration, in which mitochondrial homeostasis plays a pivotal role. Then, the decreased expression of Tfam and Cox IV;, as well as changes of mitochondrial function and morphology, demonstrated the disruption of mitochondrial homeostasis under DKD conditions. Interestingly, Sac/Val administration was found to restore mitochondrial homeostasis in DKD mice and in vitro model of HK-2 cells. Further, we demonstrated that Sirt1/PGC1α, a crucial pathway in mitochondrial homeostasis, was activated by Sac/Val both in vivo and in vitro. Finally, the beneficial effects of Sac/Val on mitochondrial homeostasis and tubulointerstitial fibrosis was partially abolished in the presence of Sirt1 specific inhibitor. CONCLUSIONS: Taken together, we demonstrate that Sac/Val ameliorates tubulointerstitial fibrosis by restoring Sirt1/PGC1α pathway-mediated mitochondrial homeostasis in DKD, providing a theoretical basis for delaying the progression of DKD in clinical practice.
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Objective: This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in China. Methods: This study was conducted by 45 tertiary Grade-A hospitals in China. Online and offline questionnaire data were obtained from patients infected with COVID-19 between December 28, 2022, and February 21, 2023. The collected information included basic demographics, medical history, smoking and drinking history, vaccination history, changes in olfactory and gustatory functions before and after infection, and other postinfection symptoms, as well as the duration and improvement status of olfactory and gustatory disorders. Results: Complete questionnaires were obtained from 35,566 subjects. The overall incidence of olfactory and taste dysfunction was 67.75%. Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction. Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction. Before infection, the average olfactory and taste VAS scores were 8.41 and 8.51, respectively; after infection, they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey. The median duration of dysosmia and dysgeusia was 15 and 12 days, respectively, with 0.5% of patients having symptoms lasting for more than 28 days. The overall self-reported improvement rate was 59.16%. Recovery was higher in males, never smokers, those who received two or three vaccine doses, and those that had never experienced dental health issues, or chronic accompanying symptoms. Conclusions: The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in China. Incidence and prognosis are influenced by several factors, including sex, SARS-CoV-2 vaccination, history of head-facial trauma, nasal and oral health status, smoking and drinking history, and the persistence of accompanying symptoms.
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OBJECTIVE: To investigate the effects of the combination of tripterygium wilfordii Hook F (TwHF) and irbesartan on urinary podocyte in diabetic kidney disease (DKD) patients, and to discuss the mechanism of protective effect of TwHF on DKD. METHODS: A total of 45 type 2 diabetic kidney disease patients were enrolled into this prospective study, and were randomly divided into 3 groups: TwHF treatment group (DT, n = 15), irbesartan treatment group (DI, n = 15), and TwHF combined with irbesartan treatment group (DTI, n = 15). After 6 weeks washout, the 3 groups were given TwHF (1-2 mg·kg⻹·d⻹), irbesartan (150-300 mg/d), and TwHF (1-2 mg·kg⻹·d⻹) combined with irbesartan (150-300 mg/d) for 12 weeks respectively. Fifteen healthy volunteers served as controls. Urinary podocytes were identified and quantitated by immunofluorescence staining of urinary sediments labeled by monoclonal antibody podocalyxin. In addition, we studied urinary connective tissue growth factor (CTGF), osteopontin (OPN) and transforming growth factor ß1 (TGFß1) concentrations in DKD patients by enzyme-linked immunosorbent assay. RESULTS: Urinary detached podocytes were obviously higher in the urine of DKD patients than in healthy controls (P < 0.01). Podocyte detection rate was 86.6% in the urine of DKD patients. The protein expressions of CTGF, OPN and TGFß1 in patients with urinary podocyte were significantly increased than those without urinary podocyte (P < 0.05 or 0.01).Correlation analysis showed that there was positive correlation between urinary protein excretion and urinary podocytes (r = 0.79, P < 0.01) and there were positive correlations between the number of urinary podocytes and urinary protein expressions of CTGF, OPN and TGFß1 (r = 0.56, 0.41, 0.44, respectively, all P values <0.01). Urinary albumin excretion and urinary podocytes were significantly decreased in all treatment groups (P < 0.01), simultaneously, urinary concentrations of CTGF, OPN and TGFß1 were reduced in all groups at week 12 after intervention of TwHF, irbesartan and TwHF combined with irbesartan(P < 0.01), and these changes were more distinguished in combined treatment group (P < 0.05). CONCLUSION: Urinary podocyte in the urine may be suggested to be an early effective marker of disease activity in DKD. TwHF may be effective to prevent podocyte injury in DKD, which may be mediated, at least partly, by down-regulating the expression of CTGF, OPN and TGFß1. There is a synergistic protective effect of TwHF combined with irbesartan on podocyte injury in DKD patients.
Subject(s)
Biphenyl Compounds/pharmacology , Diabetic Nephropathies/metabolism , Drugs, Chinese Herbal/pharmacology , Podocytes/metabolism , Tetrazoles/pharmacology , Tripterygium/chemistry , Aged , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/urine , Diabetic Nephropathies/urine , Female , Humans , Irbesartan , Male , Middle Aged , Podocytes/drug effects , Prospective StudiesABSTRACT
Saikosaponin a (Ssa) is an active ingredient of the Chinese herbal plant Radix Bupleuri (RB) and has severe hepatotoxicity. However, biomolecular mechanisms involved in Ssa-induced hepatotoxicity are not yet entirely clear. Previous studies reported that Ssd (an isomer of Ssa) as a sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA) inhibitor can induce autophagy in apoptotic defective cells, leading to autophagy-dependent cell death. Therefore, we speculate that endoplasmic reticulum (ER) stress and autophagy may also play an important role in Ssa-induced hepatocyte death. This study aimed to explore the connection between ER stress and autophagy and Ssa-induced hepatotoxicity. Experiments in vitro showed that the cell viability of L-02 cells in the Ssa treatment group decreased, the level of autophagy marker LC3-II/LC3-I and Beclin1 increased, the level of p62 decreased, the colocalization of autophagosome and lysosome increased, and the cell viability was significantly increased after the application of autophagy inhibitors 3-MA. In addition, SSa can induce ER stress in L-02 cells in vitro. Further studies demonstrated that SSa activated the PERK/eIF2α/ATF4/CHOP pathway, IRE1-TRAF2 pathway, ATF6 pathway, and AMPK/mTOR pathway associated with ER stress. Application of ER stress inhibitors 4-PBA can significantly down-regulate the level of autophagy and improve cell viability. Results of in vivo experiments showed that treatment with 150 and 300 mg/kg Ssa significantly elevated the liver/body weight ratio and caused histological injury in mice liver. Furthermore, Ssa treatment induced significantly downregulated p62 expression but upregulated LC3-II, CHOP, and GRP78 expression in mice livers. Taken together, our results showed that SSa can activate endoplasmic reticulum stress, promote toxic autophagy, and then induce cell death. We revealed an alternative mechanism involving autophagy and ERs, by which Ssa induced hepatotoxicity.
Subject(s)
Chemical and Drug Induced Liver Injury , Endoplasmic Reticulum Stress , Animals , Mice , Autophagy , ApoptosisABSTRACT
Alzheimer's disease (AD) is a degenerative disease of the central nervous system. The pathogenesis of AD has been explained using cholinergic, ß-amyloid toxicity, tau protein hyperphosphorylation, and oxidative stress theories. However, an effective treatment method has not been developed. In recent years, with the discovery of the brain-gut axis (BGA) and breakthroughs made in Parkinson's disease, depression, autism, and other diseases, BGA has become a hotspot in AD research. Several studies have shown that gut microbiota can affect the brain and behavior of patients with AD, especially their cognitive function. Animal models, fecal microbiota transplantation, and probiotic intervention also provide evidence regarding the correlation between gut microbiota and AD. This article discusses the relationship and related mechanisms between gut microbiota and AD based on BGA to provide possible strategies for preventing or alleviating AD symptoms by regulating gut microbiota.
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Mitochondrial autophagy plays an important role in maintaining the complexity of mitochondrial functions and removing damaged mitochondria, of which the PINK1-Parkin signal pathway is one of the most classical pathways. Thus, a comprehensive and in-depth interpretation of the PINK1-Parkin signal pathway might deepen our understanding on the impacts of mitochondrial autophagy. Alzheimer's disease (AD) is a classical example of neurodegenerative disease. Research on the pathogenesis and treatments of AD has been a focus of scientific research because of its complexity and the limitations of current drug therapies. It was reported that the pathogenesis of AD might be related to mitochondrial autophagy due to excessive deposition of Aß protein and aggravation of the phosphorylation of Tau protein. Two key proteins in the PINK1-Parkin signaling pathway, PINK1 and Parkin, have important roles in the folding and accumulation of Aß protein and the phosphorylation of Tau protein. In addition, the intermediate signal molecules in the PINK1-Parkin signal pathway also have certain effects on AD. In this paper, we first described the role of PINK1-Parkin signal pathway on mitochondrial autophagy, then discussed and analyzed the effect of the PINK1-Parkin signal pathway in AD and other metabolic diseases. Our aim was to provide a theoretical direction to further elucidate the pathogenesis of AD and highlight the key molecules related to AD that could be important targets used for AD drug development.
Subject(s)
Alzheimer Disease , Neurodegenerative Diseases , Humans , Alzheimer Disease/metabolism , tau Proteins/metabolism , Protein Kinases/metabolism , Neurodegenerative Diseases/metabolism , Autophagy , Ubiquitin-Protein Ligases/metabolism , MitochondriaABSTRACT
Podocyte injury is a characteristic feature of diabetic nephropathy (DN). The secretion of exosomes in podocytes increases significantly in DN; however, the precise mechanisms remain poorly understood. Here, we demonstrated that Sirtuin1 (Sirt1) was significantly downregulated in podocytes in DN, which correlated negatively with increased exosome secretion. Similar results were observed in vitro. We found that lysosomal acidification in podocytes following high glucose administration was markedly inhibited, resulting in the decreased lysosomal degradation of multivesicular bodies. Mechanistically, we indicated that loss of Sirt1 contributed to the inhibited lysosomal acidification by decreasing the expression of the A subunit of the lysosomal vacuolar-type H+ ATPase proton pump (ATP6V1A) in podocytes. Overexpression of Sirt1 significantly improved lysosomal acidification with increased expression of ATP6V1A and inhibited exosome secretion. These findings suggest that dysfunctional Sirt1-mediated lysosomal acidification is the exact mechanism of increased secretion of exosomes in podocytes in DN, providing insights into potential therapeutic strategies for preventing DN progression.
Subject(s)
Diabetes Mellitus , Diabetic Nephropathies , Exosomes , Podocytes , Humans , Podocytes/metabolism , Diabetic Nephropathies/metabolism , Sirtuin 1/metabolism , Exosomes/metabolism , Lysosomes/metabolism , Hydrogen-Ion Concentration , Diabetes Mellitus/metabolismABSTRACT
The transcription factor hypoxia-inducible factor-1α (HIF-1α), as a master regulator of adaptive responses to hypoxia, possesses two transcriptional activation domains [TAD, N-terminal (NTAD), and C-terminal (CTAD)]. Although the roles of HIF-1α NTAD in kidney diseases have been recognized, the exact effects of HIF-1α CTAD in kidney diseases are poorly understood. Here, two independent mouse models of hypoxia-induced kidney injury were established using HIF-1α CTAD knockout (HIF-1α CTAD-/-) mice. Furthermore, hexokinase 2 (HK2) and mitophagy pathway are modulated using genetic and pharmacological methods, respectively. We demonstrated that HIF-1α CTAD-/- aggravated kidney injury in two independent mouse models of hypoxia-induced kidney injury, including ischemia/reperfusion-induced kidney injury and unilateral ureteral obstruction-induced nephropathy. Mechanistically, we found that HIF-1α CTAD could transcriptionally regulate HK2 and subsequently ameliorate hypoxia-induced tubule injury. Furthermore, it was found that HK2 deficiency contributed to severe renal injury through mitophagy inhibition, while mitophagy activation using urolithin A could significantly protect against hypoxia-induced kidney injury in HIF-1α C-TAD-/- mice. Our findings suggested that the HIF-1α CTAD-HK2 pathway represents a novel mechanism of kidney response to hypoxia, which provides a promising therapeutic strategy for hypoxia-induced kidney injury.
Subject(s)
Hexokinase , Hypoxia-Inducible Factor 1, alpha Subunit , Reperfusion Injury , Animals , Mice , Disease Models, Animal , Hexokinase/genetics , Hypoxia/complications , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Kidney , Mitophagy , Transcriptional ActivationABSTRACT
OBJECTIVE: To investigate the protective effect of combination of triptolide and irbesartan on the podocytes in a type 2 diabetic(T2DM) rat model, and evaluate its mechanism. METHODS: T2DM rats were induced by fed with high-sucrose-high-fat diet combined with a low dose of streptozocin. The rats were randomly divided into 5 groups: normal control group (NC, n = 10), diabetes group (DM, n = 11), triptolide treatment group (DT, n = 12), irbesartan treatment group (DI, n = 12) and triptolide combined with irbesartan treatment group (DTI, n = 13). Ultrastructure of podocytes was observed by electronic microscopy and urinary albumin (UAL) excretion by ELISA was determined after 8 weeks. The expression of nephrin and bone morphogenetic protein-7 (BMP-7), connective tissue growth factor (CTGF), transforming growth factor (TGF)ß(1) mRNA and proteins were detected by immunohistochemistry, real-time PCR and Western blot. RESULTS: Increased UAL was significantly attenuated in all treatment groups. Compared to NC group, UAL in DM group was increased significantly (0.45 ± 0.09 vs 6.36 ± 0.87, P < 0.01), while decreased in triptolide or irbesartan alone treatment group (2.48 ± 0.37 and 2.68 ± 0.42, both P < 0.01). Compared with those in control groups, kidney expression of nephrin, BMP-7 mRNA and proteins were downregulated while CTGF, TGFß(1) mRNA and proteins were significantly upregulated in T2DM rats. Triptolide or irbesartan each alone moderately ameliorated albuminuria and podocyte damage. However, their combined usage showed a dramatic therapeutic synergism, manifested by prevention of progressive albuminuria, restoration of the glomerular filtration barrier, reversal of the decline in slit diaphragm proteins, reduction expression of CTGF, TGFß(1), and upregulation of BMP-7. CONCLUSION: Our findings show that triptolide can increase the efficacy of irbesartan, leading to a more effective prevention of kidney disease in T2DM rat model, which may through upregulation of BMP-7 and inhibition the over-expression of CTGF and TGFß(1).
Subject(s)
Biphenyl Compounds/pharmacology , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/metabolism , Diterpenes/pharmacology , Phenanthrenes/pharmacology , Podocytes/drug effects , Tetrazoles/pharmacology , Animals , Biphenyl Compounds/therapeutic use , Bone Morphogenetic Protein 7/metabolism , Connective Tissue Growth Factor/metabolism , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Diabetic Nephropathies/metabolism , Diterpenes/therapeutic use , Epoxy Compounds/pharmacology , Epoxy Compounds/therapeutic use , Irbesartan , Male , Phenanthrenes/therapeutic use , Rats , Rats, Wistar , Tetrazoles/therapeutic use , Transforming Growth Factor beta1/metabolismABSTRACT
Alzheimer's disease (AD) is a neurodegenerative disease characterized by memory loss and cognitive dysfunction in the elderly, with amyloid-beta (Aß) deposition and hyperphosphorylation of tau protein as the main pathological feature. Nuclear factor 2 (Nrf2) is a transcription factor that primarily exists in the cytosol of hippocampal neurons, and it is considered as an important regulator of autophagy, oxidative stress, and inflammation. Total saikosaponins (TS) is the main bioactive component of Radix bupleuri (Chaihu). In this study, it was found that TS could ameliorate cognitive dysfunction in APP/PS1 transgenic mice and reduce Aß generation and senile plaque deposition via activating Nrf2 and downregulating the expression of ß-secretase 1 (BACE1). In addition, TS can enhance autophagy by promoting the expression of Beclin-1 and LC3-II, increasing the degradation of p62 and NDP52 and the clearance of phosphorylated tau (p-tau), and reducing the expression of p-tau. It can also downregulate the expression of nuclear factor-κB (NF-κB) to inhibit the activation of glial cells and reduce the release of inflammatory factors. In vitro experiments using PC12 cells induced by Aß, TS could significantly inhibit the aggregation of Aß and reduce cytotoxicity. It was found that Nrf2 knock-out weakened the inhibitory effect of TS on BACE1 and NF-κB transcription in PC12 cells. Moreover, the inhibitory effect of TS on BACE1 transcription was achieved by promoting the binding of Nrf2 and the promoter of BACE1 ARE1. Results showed that TS downregulated the expression of BACE1 and NF-κB through Nrf2, thereby reducing the generation of Aß and inhibiting neuroinflammation. Furthermore, TS can ameliorate synaptic loss and alleviate oxidative stress. In gut microbiota analysis, dysbiosis was demonstrated in APP/PS1 transgenic mice, indicating a potential link between gut microbiota and AD. Furthermore, TS treatment reverses the gut microbiota disorder in APP/PS1 mice, suggesting a therapeutic strategy by remodeling the gut microbe. Collectively, these data shows that TS may serve as a potential approach for AD treatment. Further investigation is needed to clarify the detailed mechanisms underlying TS regulating gut microbiota and oxidative stress.
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AIM: To evaluate the protective effects of resveratrol on acute kidney injury (AKI) in septic rats. METHODS: A septic rat model was established by cecal ligation and puncture (CLP). A total of 108 male Sprague Dawley rats were randomly divided into an observation group, a 6 h resveratrol intervention group and a 12 h resveratrol intervention group. Then each group was subdivided into Sham, Sham + Res, CLP and CLP + Res groups. After surgery, the survival and morphological changes in kidney tissues were observed. Serum creatinine and urea nitrogen levels, expression of GRP78, BiP, IRE1 and p65 in kidney tissues, and serum levels of TNF-α, IL-1ß, IL-6 and IL-10 were investigated. RESULTS: The survival rate of CLP + Res group (75.00%) significantly exceeded that of the CLP group (41.67%) (P<0.05). At postoperative 12 h, resveratrol significantly decreased serum creatinine and urea nitrogen levels (P<0.05). Resveratrol evidently relieved renal tubular swelling and luminal narrowing in CLP rats, and significantly reduced the high expressions of GRP78, BiP, phosphorylated IRE1 and p65 proteins (P<0.05). P65 was mainly located in the cytoplasm of Sham, Sham + Res and CLP + Res groups, and in the nucleus of the CLP group. At postoperative 12 h, resveratrol significantly reduced serum levels TNF-α, IL-1ß and IL-6 in CLP rats (P<0.05), whereas elevated that of IL-10 (P<0.05). CONCLUSION: Resveratrol significantly decreased the mortality rate of septic rats and alleviated AKI, probably by attenuating endoplasmic reticulum stress, inhibiting activation of the NF-κB pathway and mitigating the inflammatory response.
Subject(s)
Acute Kidney Injury/drug therapy , Antioxidants/therapeutic use , Resveratrol/therapeutic use , Sepsis/drug therapy , Acute Kidney Injury/etiology , Acute Kidney Injury/pathology , Animals , Disease Models, Animal , Male , Rats , Rats, Sprague-Dawley , Sepsis/etiology , Sepsis/pathologyABSTRACT
Seven ternary complexes of Tb(III) were synthesized with benzoic acid (BA), o-, m-, p-methylbenzoic acid (o-MBA, m-MBA, p-MBA), and o-, m-, p-methoxybenzoic acid (o-MOBA, m-MOBA, p-MOBA) as the first ligand, and 1,10-phenanthroline (phen) as the second ligand. The content of C, H and N were measured by using a Flash-EA model 1112 elemental analyzer. Excitation and luminescence spectra of the title solid complexes were recorded by using a Hitachi F-4500 fluorescence spectrophotometer at room temperature. The effects of different varieties and different positions of replacing benzoic acid as the first ligand on fluorescence properties of the ternary complexes of terbium were discussed. The results indicated that the intensity of 5D4-->7F6 (489 nm) and 5D4-->7F5 (545 nm) of substituting benzoic acid complexes was stronger than benzoic acid. Three ternary complexes of Tb(III) with o-, m-, p-methylbenzoic acid showed emission intensity in the consecution: Tb(o-MBA)3 phen
ABSTRACT
PURPOSE: The aim of this study was to determine the diagnostic values of kidney shear wave velocity (SWV) and bone morphogenetic protein-7 (BMP-7), and their correlation in the diagnosis of early diabetic kidney disease. METHODS: A total of 150 patients with type 2 diabetes mellitus were divided into three equal groups based on the urinary albumin-creatinine ratio (ACR): normal albuminuria (normo- group, ACR < 30 mg/g creatinine, n = 50), microalbuminuria (micro- group, 30 ≤ ACR < 300 mg/g creatinine, n = 50), and macroalbuminuria (macro- group, ACR ≥ 300 mg/g creatinine and estimated glomerular filtration rate (eGFR) ≥30 ml/min/1.73 m2, n = 50). Fifty healthy volunteers were recruited to serve as controls (control group). The levels of serum BMP-7 were detected, and virtual touch tissue quantification was used to detect the renal SWV value in all study subjects. Correlations between groups as well as SWV and BMP-7 were analyzed. RESULTS: Serum BMP-7 and SWV were significantly and progressively decreased and increased, respectively, during the development of renal disease, from the normo- to the micro- and to the macro- groups (all P < 0.01 between each other for BMP-7 and SWV). Moreover, no significant differences between the normo- and control groups were observed for either BMP-7 or SWV (both P > 0.05). In addition, a significant correlation was found between SWV and BMP-7, with a coefficient of -0.569 (P < 0.05). CONCLUSION: The determination of SWV together with serum BMP-7 may play an important role in the diagnosis of diabetic kidney disease.
Subject(s)
Bone Morphogenetic Protein 7/blood , Diabetic Nephropathies/diagnosis , Kidney/diagnostic imaging , Adult , Albuminuria/urine , Case-Control Studies , Creatinine/urine , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/pathology , Diabetic Nephropathies/diagnostic imaging , Diabetic Nephropathies/etiology , Enzyme-Linked Immunosorbent Assay , Female , Glomerular Filtration Rate , Humans , Kidney/physiopathology , Male , Middle Aged , UltrasonographyABSTRACT
This study was purposed to explore the relationship between the mRNA expression of telomere protection protein TIN2 and POT1 and the pathogenesis of myelodysplastic syndrome (MDS). The expression of TIN2 and POT1 genes at the mRNA levels were detected by real-time fluorescence quantitative PCR in 51 patients with MDS and 10 normal controls. The results showed that the mRNA expressions of TIN2 in RA/RARS/RCMD/MDS-U, RAEB-1 and RAEB-2 groups according to the World Health Organization criteria were significantly higher than that in the controls (P < 0.05); the mRNA expressions of POT1 in RA/RARS/RCMD/MDS-U, RAEB-1 and RAEB-2 groups were significantly lower than that in the controls (P < 0.05). The mRNA expressions of TIN2 in high-risk group, inter risk-2 group and inter risk-1 group according to the international prognostic scoring system criteria were significantly higher than that in controls (P < 0.05). There was no significant difference between low risk group and the control group. The mRNA expressions of POT1 in high risk group, inter-risk-2 group and inter-risk-1 group were significantly lower than the controls (P < 0.05). There was no significant difference between low risk group and the control group. The mRNA expression of TIN2 in normal chromosome group was significantly lower than that in abnormal chromosome group (P < 0.05). There was no significant difference between normal chromosome group and the control group. The mRNA expression of POT1 in normal chromosome group was significantly higher than that in abnormal chromosome group (P < 0.05). There was no significant difference between normal chromosome group and the control group. It is concluded that the abnormal mRNA expression of TIN2 and POT1 may be involved in the regulation of telomere dynamics of MDS patients, the regulatory mechanism may be related to the telomere length and the pathogenesis of MDS.