Renal Tissue Damage Research Articles

Molecular pathways identified from single nucleotide polymorphisms demonstrate mechanistic differences in systemic lupus erythematosus patients of Asian and European ancestry

Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disorder with a prominent genetic component. Individuals of Asian-Ancestry (AsA) disproportionately experience more severe SLE compared to individuals of European-Ancestry (EA), including increased renal involvement and tissue damage. However, the mechanisms underlying elevated severity in the AsA population remain unclear. Here, we utilized available gene expression data and genotype data based on all non-HLA SNP associations in EA and AsA SLE patients detected using the Immunochip genotyping array. We identified 2778 ancestry-specific and 327 trans-ancestry SLE-risk polymorphisms. Genetic associations were examined using connectivity mapping and gene signatures based on predicted biological pathways and were used to interrogate gene expression datasets. SLE-associated pathways in AsA patients included elevated oxidative stress, altered metabolism and mitochondrial dysfunction, whereas SLE-associated pathways in EA patients included a robust interferon response (type I and II) related to enhanced cytosolic nucleic acid sensing and signaling. An independent dataset derived from summary genome-wide association data in an AsA cohort was interrogated and identified similar molecular pathways. Finally, gene expression data from AsA SLE patients corroborated the molecular pathways predicted by SNP associations. Identifying ancestry-related molecular pathways predicted by genetic SLE risk may help to disentangle the population differences in clinical severity that impact AsA and EA individuals with SLE.

Gene signature and prediction model of the mitophagy-associated immune microenvironment in renal ischemia-reperfusion injury.

Renal ischemia-reperfusion injury (IRI) is an inevitable occurrence during kidney transplantation. Mitophagy, ferroptosis, and the associated immune microenvironment (IME) have been shown to play important roles in renal IRI. However, the role of mitophagy-associated IME genes in IRI remains unclear. In this study, we aimed to construct a prediction model of IRI prognosis based on mitophagy-associated IME genes. The specific biological characteristics of the mitophagy-associated IME gene signature were comprehensively analyzed using public databases such as GEO, Pathway Unification, and FerrDb. Correlations between the expression of prognostic genes and immune-related genes and IRI prognosis were determined by Cox regression, LASSO analysis, and Pearson's correlation. Molecular validation was performed using human kidney 2 (HK2) cells and culture supernatant as well as the serum and kidney tissues of mice after renal IRI. Gene expression was measured by PCR, and inflammatory cell infiltration was examined by ELISA and mass cytometry. Renal tissue damage was characterized using renal tissue homogenate and tissue sections. The expression of the mitophagy-associated IME gene signature was significantly correlated with IRI prognosis. Excessive mitophagy and extensive immune infiltration were the primary factors affecting IRI. In particular, FUNDC1, SQSTM1, UBB, UBC, KLF2, CDKN1A, and GDF15 were the key influencing factors. In addition, B cells, neutrophils, T cells, and M1 macrophages were the key immune cells present in the IME after IRI. A prediction model for IRI prognosis was constructed based on the key factors associated with the mitophagy IME. Validation experiments in cells and mice indicated that the prediction model was reliable and applicable. We clarified the relationship between the mitophagy-related IME and IRI. The IRI prognostic prediction model based on the mitophagy-associated IME gene signature provides novel insights on the prognosis and treatment of renal IRI.

GPX3 and GSTT1 as biomarkers related to oxidative stress during renal ischemia reperfusion injuries and their relationship with immune infiltration.

Renal ischemia reperfusion injuries (IRIs) are very common in clinical diagnoses and treatments, which are a common cause of impaired renal functions, worsening pathological damage, affecting disease progression and hindering recovery. Renal IRIs are an inflammatory disease mediated by the adaptive and innate immune system. There is a complex interaction between oxidative stress and immune cell infiltration. Therefore, we aimed to determine biomarkers associated with oxidative stress during renal IRIs and their relationship with immune cell infiltration. A differential gene expression analysis was made based on the GSE148420 dataset from the NCBI Gene Expression Comprehensive Database (GEO) combined with 92 oxidative-stress (OS)-related genes identified in the Molecular Signatures Database. Then we identified differentially-expressed genes (DEOSGs) associated with oxidative stress, which were used for gene ontology (GO) and a Kyoto Encyclopedia of Genomes (KEGG) enrichment analysis. At the same time, we used PPI protein interaction networks and Lasso regression analysis to identify key genes, which were verified by the validation sets GSE58438 and GSE71647, as well as Western Blot detection on rat renal IRI models. At the same time, PAS staining, HE staining and immunohistochemistry were used to detect tissue damage and expression of markers related to oxidative stress during renal ischemia-reperfusion. Single-gene enrichment analysis (GSEA) was used to further clarify the underlying biological functions of key genes. Cibersort was used to analyze the immune cell infiltration during renal IRI and the correlation of key genes with immune cells. At the same time, we constructed a network of transcription-factor (TF)-Hub genes and miRNA-Hub genes. DGIDB was used to predict drugs and molecular compounds that might interact with the Hub genes. Compared with the control group, a total of 5456 differential genes (DEGs) were measured in the renal IRI group, 2486 of which were upregulated and 2970 were down-regulated. Among them, we found 30 DEGs (DEOSGs) associated with oxidative stress. The results of GO and KEGG enrichment analysis showed that these DEOSGs were mainly enriched in glutathione metabolism, the response to oxidative stress stimulation, the regulation of T cell activation and apoptosis signaling pathways. Through a protein interaction network (PPI) and a LASSO regression analysis, a total of two Hub genes were identified, namely GPX3 and GSTT1, which were validated through external validation sets and animal experiments. Through pathological methods, we found that the pathological damage of renal tissue and the expression of oxidative stress markers increased after renal ischemia-reperfusion. The results of GSEA showed that the Hub genes were related to oxidative stress pathways, apoptosis signaling pathways and immune-response-related signaling pathways. An immunoinfiltration correlation analysis showed that genes GPX3 and GSTT1 were significantly positively correlated with plasma cells and macrophage M0, while were negatively correlated with monocytes and macrophages M1 and M2. Using the Strust, Starbase and DGIDB database, we predicted that 81 transcription factors, 49 miRNAs and 13 drug or molecular compounds might interact with the Hub genes. Through a comprehensive analysis of gene expression, our findings may provide new potential biomarkers for the pathogenesis of renal IRIs and a reliable basis for its early diagnosis as well as treatment.

Quantitative evaluation of renal tissue changes in patients with liver cirrhosis by shear wave elastography.

Hepatocirrhotic nephropathy progresses rapidly and has a poor prognosis, and early detection of renal changes in patients with cirrhosis is particularly important for its prevention and treatment. The objective of this study was to evaluate the value of shear wave elastography (SWE) in the early diagnosis of hepatocirrhotic nephropathy. 206 hepatic cirrhosis patients with normal conventional renal function were enrolled and divided into Child-Pugh grade A (Group A), Child-Pugh grade B (Group B), and Child-Pugh grade C (Group C) according to the Child-Pugh grading method. Meanwhile, 60 healthy volunteers matched in age and sex were selected as the control group. The maximum Young's modulus (Emax), average Young's modulus (Emean), and minimum Young's modulus (Emin) of the left renal parenchyma were measured by SWE in all subjects. The Emax, Emean, and Emin values of the left renal parenchyma were compared between the cirrhosis and control groups. The Emax, Emean, and Emin values of left renal parenchyma in cirrhosis group were higher than those in control group (p = 0.00, 0.00, 0.00). The Emax, Emean, and Emin values of left renal parenchyma in cirrhosis group B and group C were higher than those in control group (p = 0.00, 0.00, 0.00; p = 0.00, 0.00, 0.00), but these values in cirrhosis group A were not significantly different from control group(p = 0.48, 0.52, 0.92). Comparison of the Emax, Emean, and Emin values in left renal parenchyma of three cirrhosis groups, the values of Group B and Group C were higher than those of Group A (p = 0.00, 0.00, 0.00; p = 0.00, 0.00, 0.00), and there was no significant difference between Group B and Group C (p = 0.71, 0.18, 0.39). SWE can detect renal tissue damage in patients with liver cirrhosis earlier than changes identified during routine laboratory examination by quantitatively measuring the elastic parameters of renal parenchyma and may become a new method for early diagnosis of hepatorenal syndrome.

CD5L is elevated in the serum of patients with candidemia and promotes disease progression in mouse models

To investigate the changes of CD5L levels in patients with candidemia and explore the role of CD5L in progression of candidemia. Twenty healthy control individuals, 27 patients with bacteremia and 35 patients with candidemia were examined for serum CD5L levels using ELISA, and the correlations of CD5L level with other serological indicators were analyzed. A C57BL/6 mouse model of candidemia induced by intravenous injection of Candida albicans were treated with intraperitoneal injection of recombinant CD5L protein, and renal histopathological and serological changes were analyzed to assess renal injures. The effects of CD5L treatment on general condition, fungal burden, of survival of the mice were observed, and the changes in serum IL-6 and IL-8 levels of the mice were detected using ELISA. CD5L levels were significantly elevated in patients with candidemia and positively correlated with WBC, BDG, Scr and PCT levels. The mouse model of candidemia also showed significantly increased serum and renal CD5L levels, and CD5L treatment significantly increased fungal burden in the renal tissue, elevated IL-6 and IL-8 levels in the serum and kidney, aggravated renal tissue damage, and reduced survival rate of candidemia mice. Serum CD5L levels are increased in patients with candidemia, and treatment with CD5L aggravates candidemia in mouse models.

Magnetic Response Combined with Bioactive Ion Therapy: A RONS-Scavenging Theranostic Nanoplatform for Thrombolysis and Renal Ischemia-Reperfusion Injury.

Currently, the limited efficacy of antithrombotic treatments is attributed to the inadequacy of pure drugs and the low ability of drugs to target the thrombus site. More importantly, timely thrombolysis is essential to reduce the sequelae of cardiovascular disease, but ischemia-reperfusion injury (IRI) remains a major challenge that must be solved after blood flow recovery. Herein, a multifunctional therapeutic nanoparticle (NP) based on Fe3O4 and strontium ions encapsulated in mesoporous polydopamine was successfully constructed and then loaded with TNK-tPA (FeM@Sr-TNK NPs). The NPs (59.9 min) significantly prolonged the half-life of thrombolytic drugs, which was 3.04 times that of TNK (19.7 min), and they had good biological safety. The NPs were shown to pass through vascular models with different inner diameters, curvatures, and stenosis under magnetic targeting and to enable accurate diagnosis of thrombi by photoacoustic imaging. NPs combined with the magnetic hyperthermia technique were used to accelerate thrombolysis and quickly open blocked blood vessels. Then, renal IRI-induced functional metabolic disorder and tissue damage were evidently attenuated by scavenging toxic reactive oxygen and nitrogen species and through the protective effects of bioactive ion therapy, including reduced apoptosis, increased angiogenesis, and inhibited fibrosis. In brief, we constructed a multifunctional nanoplatform for integrating a "diagnosis-therapy-protection" approach to achieve comprehensive management from thrombus to renal IRI, promoting the advancement of related technologies.

Investigating the effect of dehydromiltirone on septic AKI using a network pharmacology method, molecular docking, and experimental validation.

Acute kidney injury (AKI) is a severe and frequent complication of sepsis that occurs in intensive care units with inflammation and rapid decline in renal function as the main pathological features. Systemic inflammation, microvascular dysfunction, and tubule injury are the main causes of sepsis-induced AKI (SI-AKI). The high prevalence and death rate from SI-AKI is a great challenge for clinical treatment worldwide. However, in addition to hemodialysis, there is no effective drug to improve renal tissue damage and alleviate the decline in kidney function. We conducted a network pharmacological analysis of Salvia miltiorrhiza (SM), a traditional Chinese medicine, which is widely used for the treatment of kidney disease. Then, we combined molecular docking and a dynamics simulation to screen for the active monomer dehydromiltirone (DHT) that has therapeutic effects on SI-AKI and investigated its potential mechanism of action through experimental validation. The components and targets of SM were obtained by searching the database, and 32 overlapping genes were screened by intersection analysis with AKI targets. GO and KEGG data showed that the functions of a common gene were closely related to oxidative stress, mitochondrial function, and apoptosis. The molecular docking results combined with molecular dynamics simulations provide evidence for a binding model between DHT and cyclooxygenase-2 (COX2), both of which are mainly driven by van der Waals interactions and a hydrophobic effect. In vivo, we found that mice pretreated with an intraperitoneal injection of DHT (20mg/kg/d) for 3days ameliorated CLP surgery-induced renal function loss and renal tissue damage and inhibited inflammatory mediators IL-6, IL-1β, TNF-α, and MCP-1 production. In vitro, the DHT pretreatment decreased LPS-induced expression of COX2, inhibited cell death and oxidative stress, alleviated mitochondrial dysfunction, and restrained apoptosis in HK-2 cells. Our research indicates that the renal preventive effect of DHT is related to maintaining mitochondrial dynamic balance, restoring mitochondrial oxidative phosphorylation, and inhibiting cell apoptosis. The findings in this study provide a theoretical basis and a novel method for the clinical therapy of SI-AKI.

OGG1 aggravates renal ischemia-reperfusion injury by repressing PINK1-mediated mitophagy.

Renal ischemia-reperfusion injury (IRI) is mainly responsible for acute kidney injury for which there is no effective therapy. Accumulating evidence has indicated the important role of mitophagy in mitochondrial homeostasis under stress. OGG1 (8-oxoguanine DNA glycosylase) is known for functions in excision repair of nuclear and mitochondrial DNA. However, the role of OGG1 in renal IRI remains unclear. Herein, we identified OGG1, induced during IRI, as a key factor mediating hypoxia-reoxygenation-induced apoptosis in vitro and renal tissue damage in a renal IRI model. We demonstrated that OGG1 expression during IRI negatively regulates mitophagy by suppressing the PINK1/Parkin pathway, thereby aggravating renal ischemic injury. OGG1 knockout and pharmacological inhibition attenuated renal IRI, in part by activating mitophagy. Our results elucidated the damaging role of OGG1 activation in renal IRI, which is associated with the regulatory role of the PINK1/Parkin pathway in mitophagy.

Sodium butyrate attenuate hyperglycemia-induced inflammatory response and renal injury in diabetic mice.

The activation of the monocyte-macrophage system and the damage to the renal and pancreatic tissue are common complications in patients with diabetes induced by hyper-glycemia. This study aimed to evaluate the effect and mechanism of butyrate (NaB), a metabolite of intestinal flora, on inhibiting the inflammatory response of human monocyte-macrophages (THP-1 cells) induced by high glucose and the damage of pancreatic and renal tissue in diabetic mice. The results showed that high concentration glucose significantly up-regulated the expressions of IL-1β, TNF-α, and NLRP3 in THP-1 cells and mouse spleen, and that NaB could inhibit the overexpression of those genes. The abundance of Beclin-1, LC3B and reactive oxygen species (ROS) in THP-1 cells is increased due to the high glucose concentration, and NaB can inhibit the genes responsible for upregulating the expression. In diabetic mice, vacuolar degeneration of renal tubules was observed. Then we observed that some of the epithelial cells of the renal tubules were exfoliated and some formed tubules. NaB could alleviate these pathological lesions, but NaB cannot alleviate pancreatic injury. Our results indicated that NaB could be used for the prevention and adjuvant treatment of diabetic kidney injury.

Kaempferide ameliorates cisplatin-induced nephrotoxicity via inhibiting oxidative stress and inducing autophagy.

Acute kidney injury (AKI) caused by anti-tumor drugs, such as cisplatin, is a severe complication with no effective treatment currently, leading to the reduction or discontinuation of chemotherapy. Natural products or herbal medicines are gradually considered as promising agents against cisplatin-induced AKI with the advantages of multi-targeting, multi-effects, and less resistance. In this study, we investigated the effects of kaempferide, a natural flavonoid extracted from the rhizome of Kaempferia galanga, in experimental AKI models in vitro and in vivo. We first conducted pharmacokinetic study in mice and found a relative stable state of kaempferide with a small amount of conversion into kaempferol. We showed that both kaempferide (10 μM) and kaempferol (10 μM) significantly inhibited cisplatin-caused injuries in immortalized proximal tubule epithelial cell line HK-2. In AKI mice induced by injection of a single dose of cisplatin (15 mg/kg), oral administration of kaempferide (50 mg/kg) either before or after cisplatin injection markedly improved renal function, and ameliorated renal tissue damage. We demonstrated that kaempferide inhibited oxidative stress and induced autophagy in cisplatin-treated mice and HK-2 cells, thus increasing tubular cell viability and decreasing immune responses to attenuate the disease progression. In addition, treatment with kaempferide significantly ameliorated ischemia-reperfusion-induced renal injury in vitro and in vivo. We conclude that kaempferide is a promising natural product for treating various AKI. This study has great implications for promotion of its use in healthcare products, and help to break through the limited use of cisplatin in the clinic.

Quercetin, a Plant Flavonol Attenuates Diabetic Complications, Renal Tissue Damage, Renal Oxidative Stress and Inflammation in Streptozotocin-Induced Diabetic Rats.

Diabetes mellitus is a metabolic syndrome characterized by increased glucose levels, oxidative stress, hyperlipidemia, and frequently decreased insulin levels. The current research was carried out for eight consecutive weeks to evaluate the possible reno-protective effects of quercetin (50 mg/kg b.w.) on streptozotocin (STZ) (55 mg/kg b.w.) induced diabetes rat models. Various physiological, biochemical, and histopathological parameters were determined in control, diabetic control, and quercetin-treated diabetic rats. The current findings demonstrated that diabetes control rats showed significantly decreased body weights (198 ± 10 vs. 214 ± 13 g) and insulin levels (0.28 ± 0.04 vs. 1.15 ± 0.05 ng/mL) in comparison to normal control. Besides this, the other parameters showed increased values, such as fasting blood glucose, triglyceride (TG), and total cholesterol levels (99 ± 5 vs. 230 ± 7 mg/dL, 122.9 ± 8.7 vs. 230.7 ± 7.2 mg/dL, 97.34 ± 5.7 vs. 146.3 ± 8 mg/dL) (p < 0.05). In addition, the urea and creatinine levels (39.9 ± 1.8 mg/dL and 102.7 ± 7.8 μmol/L) were also high in diabetes control rats. After 8 weeks of quercetin treatment in STZ-treated animals, body weight, insulin, and fasting blood sugar levels were significantly restored (p < 0.05). The inflammatory markers (TNF-α, IL-6, and IL-1β) were significantly increased (52.64 ± 2, 95.64 ± 3, 23.3 ± 1.2 pg/mL) and antioxidant enzymes levels (SOD, GST, CAT, and GSH) were significantly decreased (40.3 ± 3 U/mg, 81.9 ± 10 mU/mg, 14.2 ± 2 U/mg, 19.9 ± 2 μmol/g) in diabetic rats. All the parameters in diabetic animals treated with quercetin were restored towards their normal values. Histopathological findings revealed that the quercetin-treated group showed kidney architecture maintenance, reduction of fibrosis, and decreased expression of COX-2 protein. These results determined that quercetin has reno-protective effects, and conclude that quercetin possesses a strong antidiabetic potential and might act as a therapeutic agent in the prevention or delay of diabetes-associated kidney dysfunction.

Ethanol Extract of Curcuma longa L. Protects Against Carbon Tetrachloride-Induced Oxidative Damage in Renal and Hepatic Tissues of Rats

Ethanol Extract of Curcuma longa L. Protects Against Carbon Tetrachloride-Induced Oxidative Damage in Renal and Hepatic Tissues of Rats

Depletion of macrophages with clodronate liposomes partially attenuates renal fibrosis on AKI–CKD transition

Clodronate liposomes are bisphosphonates encapsulated by liposomes that are known to induce macrophage depletion in vivo. In a previous study, clodronate liposomes improved renal ischemia/reperfusion (I/R) injury in mice, which may be due to effects on macrophage phenotypes. However, how inflammatory cytokines secretion participates is unknown. In this study, we investigated the effect of macrophages in the I/R kidney by depleting macrophages with clodronate liposomes and changing inflammatory cytokines. C57BL/6 mice underwent I/R injury with or without clodronate liposomes administration on Days 5 and 15. Tubular injury, collagen deposition, and fibrosis were detected and analyzed by histological staining, immunocytochemistry (IHC), flow cytometry (FACS), and reverse transcription–polymerase chain reaction (RT–PCR). Inflammatory cytokines were detected and analyzed by Western blotting and RT–PCR. We found that clodronate liposomes alleviated renal fibrosis and tissue damage on both Days 5 and 15. KIM-1, IL-10, and TGF-β were reduced significantly in the clodronate liposomes treatment group. However, TNF-α was not different between the clodronate liposomes treatment group and the phosphate-buffered saline treatment group on either Day 5 or Day 15. Thus, clodronate liposomes can alleviate renal fibrosis and tissue damage and reduce the inflammatory cytokines IL-10 and TGF-β, suggesting that clodronate liposomes alleviate renal fibrosis may because of M1/M2 polarization.

Paricalcitol Ameliorates Acute Kidney Injury in Mice by Suppressing Oxidative Stress and Inflammation via Nrf2/HO-1 Signaling.

Effective and targeted prevention and treatment methods for acute kidney injury (AKI), a common clinical complication, still needs to be explored. Paricalcitol is a biologically active chemical that binds to vitamin D receptors in the body to exert anti-oxidant and anti-inflammatory effects. However, the molecular mechanism of the effect of paricalcitol on AKI remains unclear. The current study uses a paricalcitol pretreatment with a mouse AKI model induced by cisplatin to detect changes in renal function, pathology and ultrastructure. Results showed that paricalcitol significantly improved renal function in mice and reduced inflammatory cell infiltration and mitochondrial damage in renal tissue. Furthermore, paricalcitol markedly suppressed reactive oxygen species and malondialdehyde levels in the kidneys of AKI mice and increased the levels of glutathione, superoxide dismutase, Catalase and total anti-oxidant capacity. In addition, we detected renal necrosis and inflammation-related proteins in AKI mice by immunofluorescence and Western blot, and found that their levels were markedly decreased after paricalcitol pretreatment. Moreover, paricalcitol promotes nuclear factor erythroid 2-related factor 2 (Nrf2) in the nucleus and activates the Nrf2/heme oxygenase-1 (HO-1) signaling pathway; while HO-1 is inhibited, the protective effect of paricalcitol on the kidney is attenuated. In conclusion, paricalcitol exerts a renoprotective effect by decreasing renal oxidative injury and inflammation through Nrf2/HO-1 signaling, providing a new insight into AKI prevention.

Vitamin E Prevented Hepatic and Renal Tissue Damage in Hypothyroid Rats.

Considering antioxidant effects of vitamin E (Vit E), in the present study, the effect of Vit E on liver and kidney functions and oxidative stress parameters in tissues of these organs of hypothyroid (Hypo) rats were reported. The animals were included in three groups:(1) control, (2) hypo, and (3) hypo-hypo-Vit E. Hypothyroidism was induced in rats by giving 0.05% propylthiouracil (PTU) in drinking water. Besides PTU, the rats in group 3 were daily injected with Vit E (20 mg/kg) for 42 days. The animals were deeply anesthetized and sacrificed, and the serum of the rats was immediately removed to measure thyroxin level and subsequent analysis. The liver and kidney tissues were also immediately removed for biochemical oxidative stress criteria. PTU administration reduced serum thyroxin level and also thiol content, superoxide dismutase (SOD), and catalase (CAT) activities in the liver and kidney tissues while increasing malondialdehyde (MDA). Hypothyroidism also increased alanine aminotransferase (ALT), blood urea nitrogen (BUN), and creatinine while decreasing albumin. Vit E increased thiol, SOD, and CAT in the liver and kidney tissues while diminished MDA. Vit E also decreased ALT, BUN, and creatinine while increased albumin. The results of this study showed that Vit E prevented liver and renal tissue damage in hypothyroid rats.

The effects of tarantula cubensis extract on renal ischemia reperfusion injury in rats.

Renal ischemia-reperfusion (IR) related acute kidney injury (AKI) is an important health problem and has not yet been fully treated. Tarantula cubensis extract (TCE) is a homeopathic drug that has antiinflammatory and antioxidant effects. This study aimed to investigate the effects of TCE on renal ischemia-reperfusion injury in rats. This study was carried out on 48 Spraque-Dawley male rats, which were divided into six groups. The first, second, and third groups were control, sham, and IR groups, respectively. Group four received IR and 0.2 mL of 96% ethanol. Group five and six received ischemia and reperfusion and TCE 0.01 and 0.1 mg per rat (which correspond to approximately 0.04 mg/kg, and 0.4 mg/kg), respectively. Tumor necrosis factor alpha (TNF-α), interleukin-1beta (IL-1β), total antioxidant status (TAS), and total oxidant status (TOS) levels in renal tissue were measured by enzyme-linked immunosorbent assay (ELISA). Oxidative stress index (OSI) was obtained by proportioning TAS and TOS. Superoxide dismutase (SOD), myeloperoxidase (MPO) activities, and malondialdehyde (MDA) levels were determined by manual spectrophotometric methods. The histopathological changes were evaluated via hematoxylineosin and immunohistochemical staining. In IR group, renal tissue TNF-α and IL-1β levels were significantly higher than control group (p < 0.0001 for both), and low(p < 0.0001 for both) and high dose (p < 0.0001 for both) TCE administration decreased these markers. Low and high doses of TCE decreased OSI values compared with IR group (p = 0.04 and p = 0.001 respectively). Although TCE decreased MDA levels, it was not statistically significant. MPO levels significantly decreased. In addition, TCE has been found to prevent hemorrhage, cast formation, and dilatation caused by IR in renal tissues stained with hematoxylin-eosin. And also, the most intense nuclear factor kappa B (NFκB) and caspase-3 immunopositivity found in IR group was decreased in both of the TCE groups. Although TCE showed a protective effect by inhibiting inflammation against IR damage in renal tissues, there was no clear effect on oxidative stress. Larger and more detailed studies are needed to clarify the issue.

A study to demonstrate the potential of Anabolic Androgen Steroid to activate oxidative tissue damage, nephrotoxicity and decline endogenous antioxidant system in renal tissue of Adult Wistar Rats.

Anabolic Androgenic steroids (AAS) are abused and reports have been made on their deleterious effects on various organs. It is imperative to report the mechanism of inducing oxidative tissue damage even in the presence of an intracellular antioxidant system by the interaction between lipid peroxidation and the antioxidant system in the kidney. Twenty (20) adult male Wistar rats used were grouped into: A- Control, BOlive oil vehicle, C- 120mg/kg of AAS orally for three weeks, and D- 7 days withdrawal group following 120mg/kg/ 21days of AAS intake. Serum was assayed for lipid peroxidation marker Malondialdehyde (MDA) and antioxidant enzyme -superoxide Dismutase (SOD). Sectioned of kidneys were stained to see the renal tissue, mucin granules, and basement membrane. AAS-induced oxidative tissue damage, in the presence of an endogenous antioxidant, is characterized by increased lipid peroxidation and decreased SOD level which resulted in the loss of renal tissue cells membrane integrity which is a characteristic of the pathophysiology of nephron toxicity induced by a toxic compound. However, this was progressively reversed by a period of discontinuation of AAS drug exposure.

Does Omeprazole, the Proton-Pump Inhibitor, Affects the Structure of the Kidney of Male Albino Rats? Histological and Laboratory Study.

This study was done to assess the injurious effects of omeprazole by an in vivo experimental study on rat kidneys. Forty-two adult male albino rats were divided into four groups: Control group (I) in which rats were not administrated any treatment. In Groups IIa, IIb, and IIc rats received daily oral omeprazole in dose of 0.75 mg per kg for 2, 4, and 6 weeks, respectively. At the end of the experiment, blood samples were collected for serum creatinine and blood urea nitrogen measurement. Then, animals were sacrificed, and kidney specimens were processed for paraffin blocks, sectioned and stained with H and E, Mallory trichrome and Periodic acid-Schiff, then examined by the light microscope. Stained sections and image analysis were used to count vacuolated cells, pyknotic nuclei, tubular casts, and area percent of collagen fiber deposition, and then, data were subjected to the statistical analysis. Examination of omeprazole-treated groups showed injury of renal corpuscles, renal tubules, and vascular congestion with inflammatory cell infiltrate in renal interstitium. Thickening of basement membrane with deposition of collagen fibers was also detected. Statistically significant increase in the number of vacuolated cells, pyknotic nuclei, hyaline casts, and area percentage of collagen fiber deposition as compared with the control group was noticed, with deterioration of renal function tests. It was concluded that the long-term use of omeprazole resulted in structural damage of rat renal tissue associated with deterioration of renal function in a time-dependent manner.

S-Nitrosoglutathione protects acute kidney injury in septic rats by inhibiting the activation of NLRP3 inflammasome.

We aimed to study the effect of S-nitroso glutathione (SNG) on acute kidney injury (AKI) in septic rats by regulating nucleotide oligomerization domain-like receptor protein 3 (NLRP3). Sprague Dawley rats were used to construct the AKI model, and biochemical methods were used to detect the levels of inflammatory factors and anti-oxidant enzymes in renal tissue. We observed the ultrastructural changes of renal tissue by transmission electron microscopy and detected the protein and mRNA levels of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain foci (ASC) and caspase-1 by western-blotting and RT-qPCR. Cecal ligation and puncture induced renal tubular epithelial tissue damage in septic rats, resulting in decreased renal function, increased levels of inflammation and decreased levels of anti-oxidant enzymes in renal tissue, and aggravated mitochondrial damage, significantly decreased mitochondrial density and enzyme complex I/II/III/IV levels (all P<0.001), and increased the protein and mRNA expression of NLRP3, ASC, and caspase-1 (all P<0.001). However, after pretreatment with SNG, the pathological damage of renal tubular epithelial tissue was reduced, the renal function was improved, the level of inflammation in renal tissue decreased and the level of anti-oxidant enzymes increased, the density of mitochondria and the level of enzyme complex I/II/III/IV were significantly increased (all P<0.001), meanwhile the protein and mRNA levels of NLRP3, ASC, and caspase-1 were all decreased significantly (all P<0.05). SNG protects AKI in septic rats by inhibiting NLRP3 inflammasome activation.

Changes of antioxidant enzymes in the kidney after cardiac arrest in the rat model.

Globally, cardiac arrest (CA) is a leading cause of death and disability. Asphyxial CA (ACA)-induced kidney damage is a crucial factor in reducing the survival rate. The purpose of this study was to investigate the role of antioxidant enzymes in histopathological renal damage in an ACA rat model at different time points. A total of 88 rats were divided into five groups and exposed to ACA except for the sham group. To evaluate glomerular function and oxidative stress, serum levels of blood urea nitrogen (BUN) and creatinine (Crtn) and malondialdehyde (MDA) levels in renal tissues were measured. To determine histopathological damage, hematoxylin and eosin staining, periodic acid-Schiff staining, and Masson's trichrome staining were performed. Expression levels of antioxidant enzymes including superoxide dismutase-1 (SOD-1), superoxide dismutase-2 (SOD-2), catalase (CAT), and glutathione peroxidase (GPx) were measured by immunohistochemistry (IHC). Survival rate of the experimental rats was reduced to 80% at 6 h, 55% at 12 h, 42.9% at 1 day, and 33% at 2 days after return of spontaneous circulation. Levels of BUN, Crtn, and MDA started to increase significantly in the early period of CA induction. Renal histopathological damage increased markedly from 6 h until two days post-CA. Additionally, expression levels of antioxidant enzymes were significantly decreased at 6 h, 12 h, 1 day, and 2 days after CA. CA-induced oxidative stress and decreased levels of antioxidant enzymes (SOD-1, SOD-2, CAT, GPx) from 6 h to two days could be possible mediators of severe renal tissue damage and increased mortality rate.