Apoptosis In Renal Tissues Research Articles

Quercetin Protects Against Hypertensive Renal Injury by Attenuating Apoptosis: An Integrated Approach Using Network Pharmacology and RNA Sequencing.

Quercetin is known for its antihypertensive effects. However, its role on hypertensive renal injury has not been fully elucidated. In this study, hematoxylin and eosin staining, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining, and Annexin V staining were used to assess the pathological changes and cell apoptosis in the renal tissues of angiotensin II (Ang II)-infused mice and Ang II-stimulated renal tubular epithelial cell line (NRK-52E). A variety of technologies, including network pharmacology, RNA-sequencing, immunohistochemistry, and Western blotting, were performed to investigate its underlying mechanisms. Network pharmacology analysis identified multiple potential candidate targets (including TP53, Bcl-2, and Bax) and enriched signaling pathways (including apoptosis and p53 signaling pathway). Quercetin treatment significantly alleviated the pathological changes in renal tissues of Ang II-infused mice and reversed 464 differentially expressed transcripts, as well as enriched several signaling pathways, including those related apoptosis and p53 pathway. Furthermore, quercetin treatment significantly inhibited the cell apoptosis in renal tissues of Ang II-infused mice and Ang II-stimulated NRK-52E cells. In addition, quercetin treatment inhibited the upregulation of p53, Bax, cleaved-caspase-9, and cleaved-caspase-3 protein expression and the downregulation of Bcl-2 protein expression in both renal tissue of Ang II-infused mice and Ang II-stimulated NRK-52E cells. Moreover, the molecular docking results indicated a potential binding interaction between quercetin and TP53. Quercetin treatment significantly attenuated hypertensive renal injury and cell apoptosis in renal tissues of Ang II-infused mice and Ang II-stimulated NRK-52E cells and by targeting p53 may be one of the potential underlying mechanisms.

Effect of Bee Bread (Perga) on Histopathological Changes and Immunohistochemical Expression of Apoptosis Markers in the Kidney of Rats Exposed to Cadmium

Cadmium (Cd) is an environmental and industrial pollutant that causes toxicity in various organs in humans and animals. Bee bread (perga) is a natural flavonoid with a wide range of pharmacological properties. This study was conducted to examine the effects of perga on Cd-induced nephrotoxicity. Thirty-two male Wistar rats were randomly divided into 4 groups, as the Control group, Cd group (5 mg/kg/day, orally), Perga group (0.5 g/kg/day, orally), and Cd + Perga group. At the end of the 28-day experiment, kidney tissue samples were taken and histopathological, immunohistochemical, and biochemical analyses were performed. Histopathologically, severe tubular and glomerular damage occurred as a result of Cd exposure in the Cd group. Immunohistochemically, there was an increase in caspas-3 and Bax expression in the renal tissue in the Cd group. According to the biochemical results, while the catalase, superoxide dismutase, and glutathione peroxidase antioxidant enzyme levels decreased in the Cd group, and the malondialdehyde levels increased. However, most of the above-mentioned Cd-induced changes were attenuated by treatment with perga in the Perga + Cd group. In conclusion, perga supplementation may alleviate Cd-induced renal injury through inhibition of apoptosis in renal tissue.

SOX4 silencing alleviates renal injury in rats with acute renal failure by inhibiting the NF-κB signaling pathway and reducing apoptosis and oxidative stress.

Acute renal failure (ARF) is a huge threat to the lives of most patients in intensive care units, and there is currently no satisfactory treatment strategy. SRY-box transcription factor 4 (SOX4) plays a key role in the development of various diseases, but its effect on ARF is unknown. Therefore, this study aimed to explore the relationship between SOX4 and ARF. Blood samples were collected from 20 ARF patients and 20 healthy volunteers. We also established an ARF rat model by excising the right kidney and ligating the left renal artery, and SOX4 knockdown in ARF rats was achieved down by means of lentiviral infection. Subsequently, we used quantitative polymerase chain reaction and western bolt assays to detect the expression levels of SOX4 and nuclear factor-κB (NF-κB) signaling pathway-related proteins in human blood or rat renal tissue and hematoxylin and eosin and terminal deoxynucleotidyl transferase (TdT) 2'-deoxyuridine 5'-triphosphate (dUTP) nick-end labeling staining to observe the pathological changes and apoptosis of renal tissue. Enzyme-linked immunosorbent assay and biochemical kits were used to measure the levels of renal function-related indicators (blood urea nitrogen, creatinine, and neutrophil gelatinase-associated lipocalin) and inflammatory factors (interleukin [IL]-1β, IL-6, and tumor necrosis factor-alpha), as well as changes in oxidative stress-related indicators (malondialdehyde [MDA], superoxide dismutase [SOD], and reactive oxygen species [ROS]) in rat serum. SOX4 expression levels in blood samples from ARF patients and renal tissue from ARF rats were significantly higher compared with those in healthy volunteers and control rats, respectively. ARF model rats displayed the typical ARF phenotype, while SOX4 silencing significantly improved pathological injury and apoptosis of renal tissue in ARF rats. Moreover, SOX4 silencing significantly inhibited increased levels of renal function-related indicators and inflammatory factors and reduced the level of excessive oxidative stress (MDA and ROS were upregulated, and SOD was downregulated) in ARF rats. SOX4 also reduced the activity of the NF-κB signaling pathway in ARF samples. Thus, SOX4 knockdown may reduce oxidative stress, the inflammatory response, and apoptosis by reducing the activity of the NF-κB signaling pathway, thereby improving renal injury in ARF rats.

N-Acetylcysteine protects against diazinon-induced histopathological damage and apoptosis in renal tissue of rats.

Diazinon (DZN) is a member of organophosphorus insecticides that has cytotoxic effects on different organs. n-Acetyl cysteine (NAC) is a widely used antioxidant in clinical, in vivo and in vitro studies. We evaluated the protective role of NAC against DZN-induced toxicity in kidney tissue of Wistar rats. 30 male Wistar rats were divided into 5 groups of control, single dose of DZN, continuous dose of DZN, single doses of DZN + NAC and continuous doses of DZN + NAC. Kidney function test (blood urea nitrogen, creatinine and uric acid) was provided. Levels of malondialdehyde (MDA), total antioxidant capacity (TAC) and total sulfhydryl (T-SH) were determined in renal tissues. Renal cells apoptosis was detected using TUNEL assay. The mRNA expressions of apoptosis, oxidative stress and inflammatory mediators, including B-cell lymphoma-2 (Bcl2), Bcl-2-associated X protein (Bax), superoxide dismutase (SOD), catalase (CAT), Interleukin 10 (IL-10), Tumor necrosis factor-α (TNF-α), Caspase-3 and Caspase-8 were analyzed in kidney tissues using Real Time PCR method. Chronic exposure to DZN was associated with severe morphological changes in the kidney, as well as impairment of its function and decreased kidney weights. Continues treatment with DZN significantly decreased the percentage of renal apoptotic cells as compared to rats treated with continuous dose of DZN alone (17.69 ± 3.67% vs. 39.46% ± 2.44%; p < 0.001). Continuous exposure to DZN significantly decreased TAC and T-SH contents, as well as SOD and CAT expression, but increased MDA contents in the kidney tissues (p < 0.001). A significant increase was observed in mRNA expression of Bax, Caspase-3, Caspase-8, as well as TNF-α following exposure to DZN, but the expression of IL-10 and Bcl2 was significantly decreased. NAC can protect kidney tissue against DZN-induced toxicity by elevating antioxidants capacity, mitigating oxidative stress, inflammation and apoptosis.

Berberine alleviates chlorpyrifos-induced nephrotoxicity in rats via modulation of Nrf2/HO-1 axis

Chlorpyrifos (CPS), an organophosphorus insecticide, is widely used for agricultural and non-agricultural purposes with hazardous health effects. Berberine (BBR) is a traditional Chinese medicine and a phytochemical with anti-inflammatory and anti-oxidative properties. The present study evaluated the effects of BBR against kidney damage induced by CPS and the underlying mechanisms. An initial study indicated that BBR 50 mg/kg was optimal under our experimental conditions. Then, 24 rats (6/group) were randomized into: control, BBR (50 mg/kg/day), CPS (10 mg/kg/day), and CPS + BBR. BBR was administration 1 h prior to CPS. Each treatment was delivered daily for a period of 28 consecutive days using a gastric gavage tube. Compared to CPS-alone treated rats, BBR effectively improved renal function by preventing the rise in serum urea, creatinine, and uric levels. The reno-protective effects of BBR were confirmed through a histological examination of kidney tissues. BBR restored oxidant-antioxidant balance in renal tissues mediated by Keap1/Nrf2/HO-1 axis modulation. In addition, BBR decreased nitric oxide (NO) and myeloperoxidase (MPO) activity. This was paralleled with the potent down-regulation of NF-κB. Furthermore, BBR exhibited anti-apoptotic activities supported by the upregulation of Bcl-2 and down-regulation of Bax and caspase-3 expression. In conclusion, our data suggest that BBR attenuates CPS-induced nephrotoxicity in rats by restoring oxidant-antioxidant balance and inhibiting inflammatory response and apoptosis in renal tissue. This is mediated, at least partly, by modulation of the Nrf2/HO-1 axis.

Colquhounia Root Tablet Promotes Autophagy and Inhibits Apoptosis in Diabetic Nephropathy by Suppressing CD36 Expression In Vivo and In Vitro.

Rat models of DN were established using streptozotocin (STZ). The primary metabolic parameters were assessed. The pathological changes of the rat kidney were investigated, and RNA sequencing was performed for each group. Renal tissue apoptosis was detected using the TUNEL assay. In rats and high glucose- (Hg-) induced HK-2 cells, RT-qPCR and western blot were used to analyze the expression of related genes and proteins. Hg medium was used to establish the diabetic kidney environment. The CCK-8 assay and flow cytometry were used to assess cell viability and apoptosis, respectively. Transmission electron microscopy was used to evaluate autophagy in vitro. CRT treatment significantly reduced albuminuria and renal tissue damage in DN rats. Furthermore, CRT administration inhibited apoptosis and promoted autophagy in DN rat kidney tissues. CRT downregulated CD36 expression and activated the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway in DN rat kidney tissues. CRT intervention inhibited Hg-induced apoptosis and reversed autophagy in HK-2 cells. Moreover, overexpression of CD36 suppressed the beneficial effects of CRT. Our study is the first to report that CRT inhibited apoptosis and promoted autophagy in vivo and in vitro, which was achieved by reducing CD36 expression and activating the AMPK pathway. Therefore, CRT may be an effective drug to treat DN.

Electroacupuncture at “Zusanli(ST36)” alleviates 5-fluorouracil-induced renal injury in colorectal cancer-bearing mice by exerting effects on oxidative stress, inflammatory responses, and cell apoptosis: 电针“足三里”减轻大肠癌荷瘤小鼠5-FU化疗后肾损伤及其氧化应激、炎症反应和细胞凋亡的研究

ObjectiveTo observe the effect of electroacupuncture at “Zusanli (ST36)” on 5-fluorouracil (5-FU)-induced renal injury in colorectal cancer-bearing mice, and to further investigate its effects on oxidative stress, inflammatory responses, and cell apoptosis in mouse renal tissue. MethodsThirty-five male BALB/c mice were randomly divided into five groups of seven mice each, namely the control, CT26, 5-FU, sham point (SP), and ST36 (which received EA at the “ST36”) groups. With the exception of the control group, each group was subjected to establishment of a subcutaneous implantation tumor model using the murine CT26 colorectal cancer cell line. Once the models were successfully established, the 5-FU, SP, and ST36 groups received 5-FU injection solution intraperitoneally at a dose of 5 mg/mL once every three days over a 21-day period. Mice in the SP and ST36 groups additionally received an EA intervention after each intraperitoneal 5-FU injection. EA were performed on mice of the SP group at bilateral sham acupoints and on mice of the ST36 group at the bilateral “ST36” using the continuous wave mode at a frequency of 2 Hz for a duration of 5 min, intervention was administered once every two days for a duration of 21 days. Samples were collected from the mice at the end of the experiment. The pathological morphology of the renal tissue was observed using hematoxylin and eosin (HE) staining; the contents of creatine (Cre), blood urea nitrogen (BUN) and malondialdehyde (MDA), and superoxide dismutase (SOD) activity were measured using biochemical assays; the expression and nuclear translocation of nuclear factor kappa B p65 subunit (NF-κB p65) were measured by immunofluorescence; the expression levels of tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in serum were measured by ELISA; cell apoptosis in renal tissue was detected using the TUNEL assay; and the expression levels of the anti-B-cell lymphoma/leukemia 2 (Bcl-2), Bcl-2-associated X protein (Bax), cleaved caspase-3, cleaved caspase-9, and cytochrome C (cyt c) in renal tissue were measured by Western blotting. ResultsCompared with the control group, mice of the CT26 group showed a significant increase in serum Cre content (P<0.01), but the difference in BUN content was not statistically significant (P>0.05). HE staining of renal tissue revealed clear structures with normal glomerular and renal tubular morphology. SOD activity was decreased (P<0.01); MDA content was increased, but the increase was not statistically significant (P>0.05). Differences in NF-κB p65 protein expression in the cytoplasm of renal tissue and serum levels of TNF-α, IL-6, and IL-1β were not statistically significant (all P>0.05). Results of immunofluorescent TUNEL staining indicated an absence of significant cell apoptosis. In the renal tissue, Bcl-2 protein expression was slightly increased (P<0.05), and the expression levels of Bax (P<0.01), cleaved caspase-3 (P>0.05), cleaved caspase-9 (P<0.01), and cyt c (P>0.05) were increased. Compared with the CT26 group, mice of the 5-FU group exhibited an increase in Cre (P<0.01) and BUN (P<0.05) content. HE staining of renal tissue revealed the presence of glomerular atrophy and dilated Bowman's capsular spaces. SOD activity was significantly decreased (P<0.01), while the increase of MDA content was not significant (P>0.05). The expression of NF-κB p65 in the nucleus and serum TNF-α, IL-6, and IL-1β levels showed significant increases (P<0.05). The cell apoptosis level was significantly increased. The protein expression of Bcl-2 (P<0.05), Bax (P<0.01), cleaved caspase-9 (P<0.01), and cyt c (P<0.05) was significantly increased. Compared with the 5-FU group, the ST36 group showed decreased serum Cre and BUN levels (both P<0.01). HE staining of renal tissue showed less renal tissue injury and less dilation of renal capsular cavities. SOD activity was significantly higher (P<0.01), while MDA content was lower (P<0.05). Nuclear expression of NF-κB p65 and serum TNF-α (P<0.05), IL-6 (P<0.05), and IL-1β (P<0.01) levels were lower. The cell apoptosis level was decreased relative to the 5-FU group. Bcl-2 protein expression was significantly increased (P<0.01), while the protein expression levels of Bax (P<0.01), cleaved caspase-3 (P<0.01), cleaved caspase-9 (P<0.01), and cyt c (P<0.05) also were reduced. ConclusionEA at “ST36” attenuated 5-FU-induced renal injury in colorectal cancer-bearing mice. The mechanism may be related to the regulation of renal oxidative stress, alleviation of inflammatory responses, and inhibition of cell apoptosis.

Nephroprotective Effects of Selenium Nanoparticles Against Sodium Arsenite-Induced Damages.

The potential effects of selenium nanoparticles (SeNPs) administration on arsenic exposure-mediated nephrotoxicity by alleviating fibrosis, inflammation, oxidative stress-related damage, and apoptosis remains more detailed investigations. After the synthesis of selenium nanoparticles (SeNPs) by sodium selenite (Na2SeO3) through a versatile and green procedure, the biosafety of SeNPs was assessed by assaying renal functions and inflammation in mice. Subsequently, nephroprotective effects of SeNPs against sodium arsenite (NaAsO2)-induced damages were confirmed by biochemical, molecular, and histopathological assays, including renal function, histological lesion, fibrosis, inflammation, oxidative stress-related damage, and apoptosis in mice renal tissues and renal tubular duct epithelial cells (HK2 cells). The excellent biocompatibility and safety of SeNPs prepared in this study were confirmed by the non-significant differences in the renal functions and inflammation levels in mice between the negative control (NC) and 1 mg/kg SeNPs groups (p>0.05). The results of biochemical, molecular, and histopathological assays confirmed that daily administration of 1 mg/kg SeNPs for 4 weeks not only ameliorated renal dysfunctions and injuries caused by NaAsO2 exposure but also inhibited the fibrosis, inflammation, oxidative stress-related damage, and apoptosis in the renal tissues of NaAsO2-exposed mice. In addition, altered viability, inflammation, oxidative stress-related damage, and apoptosis in the NaAsO2-exposed HK2 cells were effectively reversed after 100 μg/mL SeNPs supplementation. Our findings authentically confirmed the biosafety and nephroprotective effects of SeNPs against NaAsO2 exposure-induced damages by alleviating inflammation, oxidative stress-related damage, and apoptosis.

Triptolide protects against podocyte injury in diabetic nephropathy by activating the Nrf2/HO-1 pathway and inhibiting the NLRP3 inflammasome pathway

Objectives Diabetic nephropathy (DN) is the most common microvascular complication of diabetes mellitus. This study investigated the mechanism of triptolide (TP) in podocyte injury in DN. Methods DN mouse models were established by feeding with a high-fat diet and injecting with streptozocin and MPC5 podocyte injury models were induced by high-glucose (HG), followed by TP treatment. Fasting blood glucose and renal function indicators, such as 24 h urine albumin (UAlb), serum creatinine (SCr), blood urea nitrogen (BUN), and kidney/body weight ratio of mice were examined. H&E and TUNEL staining were performed for evaluating pathological changes and apoptosis in renal tissue. The podocyte markers, reactive oxygen species (ROS), oxidative stress (OS), serum inflammatory cytokines, nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway-related proteins, and pyroptosis were detected by Western blotting and corresponding kits. MPC5 cell viability and pyroptosis were evaluated by MTT and Hoechst 33342/PI double-fluorescence staining. Nrf2 inhibitor ML385 was used to verify the regulation of TP on Nrf2. Results TP improved renal function and histopathological injury of DN mice, alleviated podocytes injury, reduced OS and ROS by activating the Nrf2/heme oxygenase-1 (HO-1) pathway, and weakened pyroptosis by inhibiting the nod-like receptor (NLR) family pyrin domain containing 3 (NLRP3) inflammasome pathway. In vitro experiments further verified the inhibition of TP on OS and pyroptosis by mediating the Nrf2/HO-1 and NLRP3 inflammasome pathways. Inhibition of Nrf2 reversed the protective effect of TP on MPC5 cells. Conclusions Overall, TP alleviated podocyte injury in DN by inhibiting OS and pyroptosis via Nrf2/ROS/NLRP3 axis.

Renal Ischemia-reperfusion Injury Attenuated by Exosomes Extracted From Splenic Ischemic Preconditioning Models.

To investigate the protective effects of exosomes extracted from splenic ischemic preconditioning (sIPC) models on renal ischemia-reperfusion injury (IRI). sIPC was conducted on mice before renal IRI, and exosomes derived from sIPC mice were infused into a mouse model of renal IRI. The kidney tissue and serum were collected 24 h later. The morphological changes, inflammation and apoptosis in IR kidneys were determined by hematoxylin-eosin (HE), terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL), and Ki-67 immunohistochemical staining. In addition, the proinflammatory cytokines in serum and cell supernatant were measured with enzyme-linked immunosorbent assays (ELISAs). Then, we administered exosomes to mouse renal epithelial cells. TUNEL assays and flow cytometry were used to evaluate cell apoptosis. Bax and Bcl-2 levels were measured via Western blotting. HE staining showed that the renal IRI was attenuated after sIPC. TUNEL results showed that renal tissue apoptosis was greatly reduced after sIPC or injection of exosomes. ELISAs showed that the serum creatinine (sCr), tumor necrosis factor alpha, and interleukin-1 β levels induced by IRI decreased with sIPC. In vitro, exosomes extracted from the hypoxia/reoxygenation (H/R) splenic fibroblast model had the same protective effect. TUNEL and flow cytometry results showed that the exosomes reduced apoptosis. ELISAs showed that tumor necrosis factor alpha and interleukin-1 β were significantly increased in the H/R group but decreased due to the exosomes treated with starvation. WB results showed that Bax expression was increased and Bcl-2 expression was decreased in the H/R group. However, exosomes decreased the Bax level and increased the Bcl-2 level. Exosomes extracted from sIPC models exerted a protective effect to attenuate renal IRI.

MicroRNA-29b-3p attenuates diabetic nephropathy in mice by modifying EZH2.

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease around the world. This study investigated the role of microRNA (miR)-29b-3p in DN and the mechanism of the miR-29b-3p/EZH2 axis in DN. Peripheral blood samples of DN patients were collected and miR-29b-3p and EZH2 expression levels were evaluated using RT-qPCR. DN mouse models were successfully established, and then treated with miR-29b-3p overexpression or EZH2 silence. IL-1β, IL-6, and TNF-α levels were assessed by ELISA. Blood glucose, serum creatinine (Scr), 24-h urine volume, 24-h urine protein, and blood urea nitrogen (BUN) levels were examined by automatic biochemical analyzer detection. HE staining was performed to observe the renal histopathology, and TUNEL staining was implemented to test apoptosis in renal tissues. The binding relationship between miR-29b-3p and EZH2 was validated by using a bioinformatics website and dual luciferase reporter gene assay. miR-29b-3p was lowly expressed, and EZH2 was highly expressed in patients with DN. Overexpressing miR-29b-3p or silencing EZH2 attenuated renal dysfunction, suppressed inflammation and apoptosis, and relieved renal injuries in mice with DN. miR-29b-3p inhibited EZH2, and miR-29b-3p overexpression mitigated renal injuries in DN mice by repressing EZH2. miR-29b-3p suppresses EZH2expression thereby inhibiting the progression of DN in mice.

Rosiglitazone attenuates hypoxia-induced renal cell apoptosis by inhibiting NF-κB signaling pathway in a PPARγ-dependent manner

Background In recent years, peroxisome proliferator-activated receptor γ (PPARγ) has been found to be closely associated with hypoxia renal disease. The aim of this study was to investigate the relationship between rosiglitazone and mitochondrial apoptosis in renal tissue and its associated mechanisms. Methods Twenty-four male Sprague-Dawley rats were randomly divided into three groups (n = 8 in each): normal control group, hypoxia injury group (equal volume of 0.9% saline), and PPARγ agonist group (Rosiglitazone, 10 mg/kg · d, intraperitoneally). The hypoxia injury group and PPARγ agonist group were placed in a hypoxia chamber and the simulated altitude was set at 7,000 m for 7 days. Blood and kidney samples were collected after 7 days. The quantitative real-time polymerase chain reaction and Western blot methods were used to determine the expression of PPARγ, nuclear factor kappa-B (NF-κB), B-cell lymphoma-2 (Bcl-2), and Bax. Results The results showed that compared with the normal control group, the renal tissue of rats after hypoxia was severely damaged, as shown by massive renal tubular epithelial cell degeneration and detachment, and renal tubular dilation. The NF-κB protein expression significantly increased, the Bcl-2 protein and mRNA expression significantly decreased, and Bax protein and mRNA expression significantly increased (p < .05 for all). Renal injury was much less severe in the PPARγ agonist group compared to the hypoxia injury group. Conclusions Rosiglitazone can alleviate hypoxia renal injury, with the possible mechanism involving attenuation of apoptosis by inhibiting the activation of the NF-κB signaling pathway in a PPARγ-dependent manner and increasing Bcl-2 and decreasing Bax expression.

Klotho inhibits the formation of calcium oxalate stones by regulating the Keap1-Nrf2-ARE signaling pathway.

Oxidative damage is important in calcium oxalate (CaOx) stone development but occurs via multiple pathways. Studies have shown that klotho plays an essential role in ameliorating oxidative damage. This study aims to explore the role of klotho in CaOx stones and whether the underlying mechanism is related to the regulation of Keap1-Nrf2-ARE signaling. The levels of GSH, SOD, CAT, MDA, and ROS were examined by ELISA. The klotho, Bcl-2, caspase-3, Keap1, Nrf2, HO-1, and NQO1 mRNA levels were measured by qRT‒PCR, and their protein levels were detected by Western blotting. Renal tissue apoptosis was examined by TUNEL staining, and crystal cell adherence and apoptosis in HKC cells were assessed based on the Ca2+ concentrations and by flow cytometry. The renal pathological changes and the adhesion of CaOx crystals in the kidneys were examined by hematoxylin-eosin and von Kossa staining, respectively. We constructed a CaOx kidney stone model in vitro. By regulating the klotho gene, klotho overexpression inhibited the CaOx-induced promotion of crystal cell adherence and apoptosis in HKC cells, and these effects were reversed by klotho knockdown. Moreover, our in vivo assay demonstrated that klotho overexpression alleviated glyoxylate administration-induced renal oxidative damage, renal apoptosis, and crystal deposition in the kidneys of mice, and these effects were also associated with activation of the Keap1-Nrf2-ARE pathway. Klotho protein inhibits the oxidative stress response of HKC cells through the Keap1-Nrf2-ARE signaling pathway, reduces the apoptosis of and adhesion of CaOx crystals to HKC cells, and decreases the occurrence of CaOx kidney stones. 20220304.

Trifolirhizin relieves renal injury in a diabetic nephropathy model by inducing autophagy and inhibiting oxidative stress through the regulation of PI3K/AKT/mTOR pathway

Purpose: To evaluate the effects of trifolirhizin on diabetic nephropathy (DN), and the mechanism of action. &#x0D; Methods: Male db/db mice (8 weeks, n = 24) and age-matched control mice (n = 6) were obtained. The mice were further divided into four groups and administered increasing doses of trifolirhizin (0, 12.5, 25 and 50 mg/kg). Histological analysis of renal tissues were performed by H &amp; E staining. Blood urea nitrogen (BUN) and creatinine were determined using enzyme-linked immunosorbent assay (ELISA). Immunoblot and TUNEL assay were performed to investigate the effect of trifolirhizin on autophagy and apoptosis, while ELISA and dihydroethidium (DHE) staining were conducted to evaluate reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) levels. The effect of trifolirhizin on PI3K/AKT/mTOR pathway was determined using Immunoblot assays. &#x0D; Results: Trifolirhizin alleviated renal injury in diabetic mice, and also activate autophagy and inhibited apoptosis in the renal tissues in diabetic mice (p &lt; 0.001). In addition, trifolirhizin inhibited the oxidative stress response in the renal tissue in diabetic mice (p &lt; 0.001). Trifolirhizin further inhibited PI3K/AKT/mTOR pathway and therefore relieved renal injury in the diabetic nephropathy model (p &lt; 0.001). &#x0D; Conclusion: Trifolirhizin alleviates renal injury in diabetic mice, activates autophagy, and inhibits apoptosis in renal tissue of diabetic mice. Therefore, trifolirhizin is a promising a promising drug for the treatment of DN.

Sufentanil promotes autophagy and improves ischemia-reperfusion-induced acute kidney injury via up-regulating microRNA-145.

Sufentanil has a good protective effect on myocardial and liver injury caused by ischemia reperfusion (IR), but its protective effect on kidney is still unclear. This study aims to investigate whether sufentanil can prevent IR-induced acute kidney injury (AKI) and to determine whether its efficacy is related to miR-145-mediated autophagy. A total of 40 rats were randomly divided into 5 groups (n=8 in each group): A sham group, an IR group, a sufentanil group, a sufentanil+miR-145 inhibitor control group (an anti-NC group) and a sufentanil+miR-145 inhibitor group (an anti-miR-145 group). Except for the sham group, the other groups established a rat AKI model induced by IR. The sufentanil group, the sufentanil+anti-NC group, and the sufentanil+anti-miR-145 were injected with sufentanil (1 μg/kg) through femoral vein 30 min before ischemia. The sufentanil+anti-NC group and the sufentanil+anti-miR-145 group were injected with miR-145 inhibitor control or anti-miR-145 (80 mg/kg) through the tail vein before sufentanil pretreatment. The structure and function of kidneys harvested from the rats were evaluated, and the protein levels of autophagy-related proteins, oxidative stress levels, and apoptosis levels were measured. Compared with the IR group, the renal structure and function were improved in the sufentanil group. The levels of blood urea nitrogen (BUN), creatinine (Cr), urinary kidney injury molecule 1 (KIM-1), neutrophil gelatinase related lipid transporter (NGAL), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6 and ROS were significantly decreased (all P<0.05). In addition, compared with the IR group, the levels of Beclin-1 and LC3 in renal tissues in the sufentanil group were significantly increased (both P<0.05), and the apoptosis in renal tissues was significantly reduced (P<0.05). Compared with the sufentanil+anti-NC group, the levels of BUN, Cr, KIM-1, NGAL, TNF-α, IL-1β, IL-6 and ROS in the sufentanil+anti-miR-145 group were significantly increased (all P<0.05), the levels of Beclin-1 and LC3 in renal tissues were significantly decreased (both P<0.05), and the apoptosis in renal tissues was significantly increased (P<0.05). Sufentanil can prevent the AKI induced by IR, which is related to the up-regulation of miR-145-mediated autophagy.

The α7 nicotinic acetylcholine receptor agonist PNU-282987 ameliorates sepsis-induced acute kidney injury through CD4+CD25+ regulatory T cells in rats.

The ameliorative effects of α7 nicotinic acetylcholine receptor (α7nAChR) agonists have been demonstrated in acute kidney injury (AKI) caused by multiple stimulations. However, the ameliorative effect of α7nAChR on sepsis-induced acute kidney injury (SAKI) in the cecal ligation and puncture (CLP) model is unclear. Previous studies have demonstrated that α7nAChR is highly expressed on the surface of CD4+CD25+ regulatory T cells (Tregs). However, the role of Tregs in SAKI is unclear. We hypothesized that Tregs might play a role in the ameliorative effect of α7nAChR on SAKI. Hence, in this study, we determined the effects of PNU-282987 (a selective α7nAchR agonist) on SAKI and evaluated whether PNU-282987 would attenuate SAKI via regulating Tregs. Our study showed that immediate administration of PNU-282987 after CLP surgery in rats improved renal function, reduced levels of systemic inflammatory factors (tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), etc.), inflammatory cell infiltration and tubular apoptosis in renal tissues, and increased forkhead/winged helix transcription factor p3 (Foxp3) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) expression indicating activated Tregs. Moreover, in in vitro experiments, isolated Tregs co-cultured with PNU-282987 also displayed enhanced expression of CTLA-4 and Foxp3. Furthermore, Tregs were co-cultured with PNU-282987 for 24 hours and then reinfused into rats through the tail vein immediately after CLP surgery, and a significant renal protective effect was observed 24 hours postoperatively. These results demonstrate that PNU-282987 exerts its renal protective effects on SAKI through activation of Tregs.

Antioxidant and antiapoptotic effects of quercetin against ochratoxin A-induced nephrotoxicity in broiler chickens

The mycotoxin ochratoxin A (OTA) is produced by the fungi Aspergillus and Penicillium. The flavonoid quercetin (QUE) is distinguished by its antioxidant, anti-inflammatory, and antiapoptotic properties. This study was designed to determine whether QUE can protect broiler chickens against OTA-induced nephrotoxicity. Forty broiler chicks were randomly divided into four equal groups: control, OTA, QUE, and OTA + QUE. For 6 weeks, OTA (0.5 mg/kg) and/or QUE (0.5 g/kg) were added to the diet of chickens. The results demonstrated that OTA exposure increased serum levels of creatinine, uric acid, and blood urea nitrogen. OTA exposure also increased renal malondialdehyde content but decreased renal antioxidants. OTA-exposed chickens exhibited multiple pathological kidney lesions. Moreover, OTA exposure induced apoptosis in renal tissue, which was manifested by the up-regulation of proapoptotic genes and down-regulation of antiapoptotic genes via the suppression of the PI3K/AKT pathway. In addition, coadministration of QUE and OTA mitigated most of these nephrotoxic effects.

1,2,3,4,6‑penta‑O‑galloyl‑β‑D‑glucose alleviates inflammation and oxidative stress in diabetic nephropathy rats through MAPK/NF‑κB and ERK/Nrf2/HO‑1 signaling pathways.

Diabetic nephropathy (DN) is one of the main causes of chronic renal failure, which is also the final cause of mortality in ~30% of diabetic patients. 1, 2, 3, 4, 6-penta-O-galloyl-β-D-glucose (PGG) from Galla rhois has anti-inflammation, anti-oxidation and angiogenesis effects. The present study aimed to explore the protective effects on diabetic nephropathy rats by alleviating inflammation and oxidative stress and the underlying mechanism. High-fat diet/STZ induced rats and high glucose (HG) induced podocytes (MPC5) were used to simulate the DN in vivo and in vitro. The blood glucose level was measured using a blood glucose meter and renal function was determined by an automatic biochemical analyzer. The pathological changes and renal fibrosis were observed through hematoxylin and eosin, periodic acid-Schiff and Masson staining. The expression of nephrin in tissues, fibrosis-related proteins in tissues, MAPK/NF-κB and ERK/nuclear factor erythroid-derived 2-related factor 2 (Nrf2)/hemeoxygenase-1 (HO-1) signaling pathway related proteins in tissues and apoptosis related proteins in tissues and podocytes was detected by western blotting. The inflammatory response and oxidative stress in tissues and podocytes were determined by respective commercial kits and apoptosis in tissues and podocytes was detected by TUNEL assay. The viability of podocytes treated with PGG with or without HG was analyzed by CCK-8 assay. As a result, the blood glucose level, urinary albumin/creatinine ratio, blood urea nitrogen and serum creatinine in blood were all increased and nephrin expression was decreased. The pathological changes and renal fibrosis were aggravated and the inflammation, oxidative stress and apoptosis in renal tissues were enhanced. The above effects were reversed by PGG treatment dose-dependently. MAPK/NF-κB and ERK/Nrf2/HO-1 signaling pathways were activated in DN rats and were suppressed by PGG treatment. The reduced viability and increased apoptosis, inflammation and oxidative stress in MPC5 cells were shown in HG induction, which was reversed by PGG treatment. However, P79350 (p38 agonist) and LM22B-10 (ERK1/2 agonist) weakened the effect of PGG. In conclusion, PGG protects against DN kidney injury by alleviating inflammation and oxidative stress by suppressing the MAPK/NF-κB and ERK/Nrf2/HO-1 signaling pathways.

Harmine mitigates cisplatin-induced renal injury in male mice through antioxidant, anti-inflammatory, and anti-apoptosis effects.

Background and purpose:Cisplatin is a chemotherapeutic drug used to treat cancer, however, causes kidney toxicity. Harmine is a plant-derived alkaloid with a wide range of therapeutic applications. The effects of harmine on the renal side effects of cisplatin in mice were studied in this study.Experimental approach:Forty-eight male BALB/c mice were randomly divided into eight groups (n = 6). They were treated with saline, cisplatin (5.5 mg/kg), harmine (5, 10, and 15 mg/kg/day), cisplatin + harmine (5, 10, and 15 mg/kg/day), respectively. All administrations were done daily and intraperitoneally for 4 days. The criteria related to histology, oxidation, anti-oxidation, inflammation, and apoptosis of renal tissue were evaluated.Findings / Results:There was a significant decrease in total antioxidant capacity of renal tissue, renal corpuscles diameter, and IL-10 expression level in the cisplatin group than in the control group, while the values of these parameters were significantly similar to the control group in the moderate or high doses of harmine + cisplatin groups. There were significant increases in serum urea and creatinine levels, bowman space, the amounts of malondialdehyde, apoptosis rate, and TNF-α, NF-κB, IL-1β, and caspase-3 gene expressions in kidney tissue of the cisplatin group compared to the control group, while these criteria did not differ in the moderate or high doses of harmine + cisplatin groups.Conclusion and implications:Harmine protected the kidneys against cisplatin-induced damage. Antioxidant, anti-inflammatory, and anti-apoptotic harmine properties were involved in this healing effect.

KLF4 Affects Acute Renal Allograft Injury via Binding to MicroRNA-155-5p Promoter to Regulate ERRFI1

Kruppel-like factor 4 (KLF4) owns the promising potential in treating kidney injury, which inevitably occurs during renal allograft. Given that, this research targets to unveil KLF4-oriented mechanism from microRNA-155-5p/ERBB receptor feedback inhibitor 1 (miR-155-5p/ERRFI1) axis in acute renal allograft injury. Mice were injected with miR-155-5p-related sequences before acute renal allograft modeling. Afterwards, serum inflammation, along with oxidative stress, renal tubular injury, and apoptosis in renal tissues were detected. HK-2 cells were processed by hypoxia/reoxygenation (H/R) and transfected with miR-155-5p- or ERRFI1-related sequences, after which cell proliferation and apoptosis were measured. KLF4, miR-155-5p, and ERRFI1 expressions and their interaction were tested. KLF4 and miR-155-5p levels were enhanced, and ERRFI1 level was repressed in mice after acute renal allograft and in H/R-treated HK-2 cells. KLF4 bound to the promoter of miR-155-5p. Depleting miR-155-5p reduced serum inflammation and attenuated oxidative stress, renal tubular injury, and apoptosis in mice with acute renal allograft injury. Downregulating miR-155-5p facilitated proliferation and repressed apoptosis of H/R-treated HK-2 cells. miR-155-5p targeted ERRFI1. Knocking down ERRFI1 antagonized the effects of downregulated miR-155-5p on acute renal allograft injury, as well as on H/R-treated HK-2 cell proliferation and apoptosis. A summary displays that silencing KLF4 suppresses miR-155-5p to attenuate acute renal allograft injury by upregulating ERRFI1, which provides a way to control acute renal allograft injury.