Pyrrolidine dithiocarbamate inhibits mouse acute kidney injury induced by diclofenac by targeting oxidative damage, cytokines and NF-κB activity

DACH1 attenuated PA-induced renal tubular injury through TLR4/MyD88/NF-κB and TGF-β/Smad signalling pathway

BACKGROUND

Palmitic acid (PA), the major saturated fatty acid in the blood, often induces the initiation and progression of diabetic kidney disease (DKD). However, the underlying mechanism remains unclear. DACH1 is an important regulator of kidney functions. Herein, we investigated the roles of DACH1 in PA-induced kidney injury.

METHODS

Clinical data from the NHANES database were subjected to analyse the association between serum PA (sPA), blood glucose and kidney function. Molecular docking of PA was performed with DACH1. Immunohistochemistry, cell viability, annexin V/7-AAD double staining, TUNEL assay, immunofluorescent staining, autophagic flux analysis, qRT-PCR and western blot were performed.

RESULTS

Clinical data confirmed that sPA was increased significantly in the pathoglycemia individuals compared with controls and correlated negatively with renal function. Our findings suggested that PA could dock with DACH1. DACH1 enhances cell viability by inhibiting apoptosis and attenuating autophagy blockage induced by PA. Furthermore, the results demonstrated that DACH1 ameliorated inflammation and fibrosis through TLR4/MyD88/NF-κB and TGF-β/Smad signalling pathway in PA-treated renal tubular epithelial cell line (HK-2).

CONCLUSIONS

This study proved that sPA presents a risk factor for kidney injuries and DACH1 might serve as a protective target against renal function deterioration in diabetic patients.

Unveiling biomarkers and therapeutic targets in IgA nephropathy through large-scale blood transcriptome analysis

INTRODUCTION

IgA nephropathy (IgAN) is the most prevalent form of glomerulonephritis. Unfortunately, molecular biomarkers for IgAN derived from omics studies are still lacking. This research aims to identify critical genes associated with IgAN through large-scale blood transcriptome analysis.

METHODS

We constructed novel blood transcriptome profiles from peripheral blood mononuclear cells (PBMCs) of 53 Chinese IgAN patients and 28 healthy individuals. Our analysis included GO, KEGG, and GSEA for biological pathways. We analyzed immune cell profiles with CIBERSORT and constructed PPI networks with STRING, visualized in Cytoscape. Key differentially expressed genes (DEGs) were identified using CytoHubba and MCODE. We assessed the correlation between gene expressions and clinical data to evaluate clinical significance and identified hub genes through machine learning, validated with an open-access dataset. Potential drugs were explored using the CMap database.

RESULTS

We identified 333 DEGs between IgAN patients and healthy controls, mainly related to immune response and inflammation. Key pathways included NK cell mediated cytotoxicity, complement and coagulation cascades, antigen processing, and B cell receptor signaling. Cytoscape revealed 16 clinically significant genes (including KIR2DL1, KIR2DL3, VISIG4, C1QB, and C1QC, associated with sub-phenotype and prognosis). Machine learning identified two hub genes (KLRC1 and C1QB) for a diagnostic model of IgAN with 0.92 accuracy, validated at 1.00 against the GSE125818 dataset. Sirolimus, calcifediol, and efaproxiral were suggested as potential therapeutic agents.

CONCLUSION

Key DEGs, particularly VISIG4, KLRC1, and C1QB, emerge as potential specific markers for IgAN, paving the way for future targeted personalized treatment options.

α-Tocopherol Ameliorates Redox Equilibrium Disorders and Reduces Inflammatory Response Caused by Diclofenac-Induced Nephrotoxicity in Male Wistar Rats

Background Diclofenac (DCF), a nonsteroidal anti-inflammatory drug (NSAID), is widely used for its analgesic and anti-inflammatory properties, but it can also be nephrotoxic. Vitamin E (α-tocopherol) has been shown to protect against renal toxicity caused by various agents, including NSAIDs. This study aims to evaluate the pathophysiology of renal damage and the nephroprotective effect of vitamin E against DCF-induced renal damage in male Wistar rats. Animal and methods Twenty-four male Wistar rats, divided into six equal groups, were used for the study. Group 1 (control group) was treated with distilled water only, while the other groups received either high or low doses of DCF with or without a fixed dose of vitamin E. Renal function was assessed by measuring serum urea, creatinine, and kidney injury molecule-1 (KIM-1). Oxidative damage and renal antioxidant levels were also assessed. Additionally, the expression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), renal cytokine tumor necrosis factor-α (TNF-α), and histopathological changes were evaluated. Results DCF caused a significant increase in serum urea, creatinine, KIM-1, TNF-α, NF-κB, and malondialdehyde levels compared to the control group. However, in the groups treated with DCF plus vitamin E, a significant reduction (P<0.05) in the levels of pro-inflammatory cytokines and malondialdehyde was observed, along with improvement in renal function indices, superoxide dismutase, catalase, and glutathione peroxidase levels comparable to the control group. The observed renal histopathological changes were consistent with the results of the biochemical parameters between the treated groups and the normal control rats. Conclusion Findings from this investigation suggested that DCF can be nephrotoxic at a certain dose when used for a prolonged duration. Co-administration of vitamin E suppressed the elevated inflammatory cytokines and led to changes in the cell redox-sensitive signaling pathways induced by DCF, with eventual amelioration of the nephrotoxicity.

Pathological study of proximal tubule mitochondria in diclofenac-induced acute kidney injury model mice

Diclofenac, a non-steroidal anti-inflammatory drug, reportedly targets mitochondria and induces nephrotoxicity via reactive oxygen species. However, there are few detailed reports of pathological analyses of mitochondria and the factors that cause acute kidney injury (AKI) as a result of nephrotoxicity. In this study, we investigated mitochondrial damage in the proximal tubule in AKI mice at 6, 12, and 24 h after administration of diclofenac. Statistical analysis of immunohistochemistry results confirmed that expression of p62 and LC3, which is associated with autophagy, reached a maximum level in the degenerated proximal renal tubule 12 h after diclofenac treatment, with high autophagy activity. Electron microscopy images provided clear evidence that confirmed mitochondrial degeneration and injury as well as autophagy (mitophagy) in mitochondria treated with diclofenac. The purpose of this study was to pathologically characterize both mitochondrial damage in the proximal renal tubules induced by diclofenac and the course of mitophagy to remove the damaged mitochondria. This report provides important information regarding mitochondrial damage in the proximal tubules in diclofenac-induced nephropathy.

The role of inflammation in cadmium nephrotoxicity: NF-κB comes into view

Kidney diseases are major health problem and understanding the underlined mechanisms that lead to kidney diseases are critical research points with a marked potential impact on health. Cadmium (Cd) is a heavy metal that occurs naturally and can be found in contaminated food. Kidneys are the most susceptible organ to heavy metal intoxication as it is the main route of waste excretion. The harmful effects of Cd were previously well proved. Cd induces inflammatory responses, oxidative injury, mitochondrial dysfunction and disturbs Ca²⁺ homeostasis. The nuclear factor-kappa B (NF-κB) is a cellular transcription factor that regulates inflammation and controls the expression of many inflammatory cytokines. Therefore, great therapeutic benefits can be attained from NF-κB inhibition. In this review we focused on certain compounds including cytochalasin D, mangiferin, N-acetylcysteine, pyrrolidine dithiocarbamate, roflumilast, rosmarinic acid, sildenafil, sinapic acid, telmisartan and wogonin and certain plants as Astragalus Polysaccharide, Ginkgo Biloba and Thymus serrulatus that potently inhibit NF-κB and effectively counteracted Cd-associated renal intoxication. In conclusion, the proposed NF-κB involvement in Cd-renal intoxication clarified the underlined inflammation associated with Cd-nephropathy and the beneficial effects of NF-κB inhibitors that make them the potential to substantially optimize treatment protocols for Cd-renal intoxication.

The Flavonoid Hesperidin Methyl Chalcone Targets Cytokines and Oxidative Stress to Reduce Diclofenac-Induced Acute Renal Injury: Contribution of the Nrf2 Redox-Sensitive Pathway

Hesperidin is derived from citrus fruits among other plants. Hesperidin was methylated to increase its solubility, generating hesperidin methyl chalcone (HMC), an emerging flavonoid that possess anti-inflammatory and antioxidant properties. The nuclear factor erythroid 2-related factor 2 (Nrf2) is a powerful regulator of cellular resistance to oxidant products. Previous data evidenced HMC can activate Nrf2 signaling, providing antioxidant protection against diverse pathological conditions. However, its effects on kidney damage caused by non-steroidal anti-inflammatory drugs (NSAIDs) have not been evaluated so far. Mice received a nephrotoxic dose of diclofenac (200 mg/kg) orally followed by intra-peritoneal (i.p.) administration of HMC (0.03–3 mg/kg) or vehicle. Plasmatic levels of urea, creatinine, oxidative stress, and cytokines were assessed. Regarding the kidneys, oxidative parameters, cytokine production, kidney swelling, urine NGAL, histopathology, and Nrf2 mRNA expression and downstream targets were evaluated. HMC dose-dependently targeted diclofenac systemic alterations by decreasing urea and creatinine levels, and lipid peroxidation, as well as IL-6, IFN-γ, and IL-33 production, and restored antioxidant properties in plasma samples. In kidney samples, HMC re-established antioxidant defenses, inhibited lipid peroxidation and pro-inflammatory cytokines and upregulated IL-10, reduced kidney swelling, urine NGAL, and histopathological alterations. Additionally, HMC induced mRNA expression of Nrf2 and its downstream effectors HO-1 and Nqo1, as well as reduced the levels of Keap1 protein detected in renal tissue. The present data demonstrate HMC is a potential compound for the treatment of acute renal damage caused by diclofenac, a routinely prescribed non-steroidal anti-inflammatory drug.

Quercetin exerts an ameliorative effect in the rat model of diclofenac-induced renal injury through mitigation of inflammatory response and modulation of oxidative stress

Diclofenac (DIC) is administrated to treat pain, inflammatory disorders, and dysmenorrhea but kidney problems are the main worries of the agent. The literature has revealed that quercetin (QR) has anti-inflammatory and antioxidant attributes. This study aims to highlight the possible nephroprotective effects of QR on DIC-exposed rats.

In this study, the animals after exposure to DIC (50 mg/kg, i.p) were administrated to QR (100 mg/kg, p.o). Then, the levels, as well as the activity of several oxidant and anti-oxidant mediators, were evaluated.

Our results showed that DIC treatment was coupled with the elevation in the levels of malondialdehyde (MDA), nitric oxide (NO), and some pro-inflammatory factors such as TNF-α, NF-κB, and IL-1β, suggesting that probably this agent exert its toxicity in the kidney tissue through inducing both oxidative stress and inflammation. Interestingly, QR was successful in restoring the activity of antioxidant compounds such as GSH, GPx, SOD, and CAT in the kidney tissue of DIC-treated rats. Moreover, in the presence of QR, DIC was unable to increase the expression of pro-inflammatory cytokines, suggesting that perhaps QR might have anti-inflammatory properties. In agreement with this, the results of the histopathological evaluation also showed that while DIC increased the lymphocyte infiltration into the kidney tissue, QR reduced the number of lymphocytes in DIC-treated rats.

The results revealed that QR exerted a supportive effect against diclofenac-induced renal injury in male rats through modulation of oxidative stress and mitigation of inflammatory response.

6-Paradol alleviates Diclofenac-induced acute kidney injury via autophagy enhancement-mediated by AMPK/AKT/mTOR and NLRP3 inflammasome pathways

Diclofenac (DIC)-induced acute kidney injury (AKI) causes high morbidity and mortality. With the absence of satisfactory treatment, we investigated the protective effects of 6-Paradol (PDL) against DIC-induced AKI, with focus on renal autophagy and NLRP3 inflammasome pathways . PDL has anti-inflammatory, antioxidant and AMPK-activation properties. PDL was administered to DIC-challenged rats. Nephrotoxicity, oxidative stress, inflammatory, and autophagy markers and histopathological examinations were evaluated. Compared to DIC, PDL restored serum nephrotoxicity, renal oxidative stress and pro-inflammatory markers. PDL almost restored renal architecture, upregulated renal Nrf2 pathway via enhancing Nrf2 mRNA expression and HO-1 levels. PDL suppressed renal NF-κB mRNA expression, and NLRP3 inflammasome pathway expression. Moreover, PDL enhanced renal autophagy through upregulating LC3B, AMPK and SIRT-1, and suppressed mTOR, p-AKT mRNA expressions and phosphorylated-p62 levels. Our study confirmed that autophagy suppression mediates DIC-induced AKI via AMPK/mTOR/AKT and NLRP3-inflammasome pathways. Also, PDL's nephroprotective effects could provide a promising therapeutic approach against DIC-induced AKI.

Laminaria japonica fucoidan ameliorates cyclophosphamide-induced liver and kidney injury possibly by regulating Nrf2/HO-1 and TLR4/NF-κB signaling pathways

BACKGROUND

During clinical practice, cyclophosphamide (CTX) can lead to liver and kidney injury in vivo. In this study, we established a liver and kidney injury model by injecting CTX (80 mg kg-1  d-1 ) into male ICR mice, and then mice were treated with saline and fucoidan (20 or 40 mg kg-1 ), respectively. Subsequently, the liver and kidney toxicity indices, the expression levels of malonic dialdehyde (MDA), inflammatory factors, and the main protein levels of the Nrf2/HO-1 and TLR4/NF-κB pathways were determined.

RESULTS

Our results indicated that fucoidan could significantly decrease serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine (CRE), and urea (BUN) in the test group compared to the model group. Fucoidan administration caused reductions in MDA, interleukin-6 (IL-6), IL-1β, and tumor necrosis factor alpha (TNF-α) levels and improved superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities in the liver and kidney of CTX-induced mice. Fucoidan up-regulated the Nrf2/HO-1 pathway and enhanced the protein levels of Nrf2, HO-1, GCLM, and NQO1. Moreover, fucoidan down-regulated the TLR4/NF-κB pathway, as indicated by decreased levels of TLR4, NF-κB p65, NF-κB p50, and increased IκBα level in liver and kidney tissues.

CONCLUSION

Our studies suggest that fucoidan can ameliorate CTX-induced liver and kidney injury, potentially via up-regulating the Nrf2/HO-1 pathway and inhibiting the TLR4/NF-κB pathway. © 2021 Society of Chemical Industry.

Extraction kinetic model of polysaccharide from Codonopsis pilosula and the application of polysaccharide in wound healing

The crude polysaccharide (CPNP) of Codonopsis pilosula was obtained by hot-water extraction technology. The extraction kinetic model established according to Fick's first law of diffusion and related parameters of polysaccharide was studied. CPNP microcapsules were prepared by blending with sodium alginate, Ca2+ ions and crude CPNP. The quality control (Drug loading rate, embedding rate and release rate, etc) of CPNP microcapsules were analyzed by pharmacopeas standards. The structure feature of CPNP microcapsules also were determined with various methods. The wound healing ability of CPNP microcapsules loading with different concentration of CPNP was evaluated using the rat wound model. The activity of various enzymes and the expression levels of pro-inflammatory factors in the model skin tissue also were determined by enzyme linked immunosorbent assay (ELISA). Hematoxylin-eosin staining (HE), Masson, immunohistochemistry were used to investigate the external application effect of CPNP microcapsules on skin wound repair. The extraction kinetics of CPNP was established with the linear correlation coefficient (R2) of 0.83-0.93, implied that the extraction process was fitted well with the Fick's first law of diffusion. The CPNP has good compatibility with sodium alginate and Ca2+ ions by SEM and TEM observation, and the particle size of CPNP microcapsules was 21.25±2.84 μm with the good degradation rate, loading rate (61.59%) and encapsulation rate (55.99%), maximum swelling rate (397.380 ±25.321%). Compared with control group, the redness, and swelling, bleeding, infection, and exudate of the damaged skin decreased significantly after CPNP microcapsules treatment, and the CPNP microcapsules groups exhibited good wound healing function with less inflammatory cell infiltration. The pathological structure showed that in the CPNP microcapsules group, more newborn capillaries, complete skin structure, and relatively tight and orderly arrangement of collagen fibers were observed in the skin of rats. CPNP microcapsules could effectively inhibit the high expression of pro-inflammatory factors in damaged skin, and significantly increase the contents of related enzymes (GSH-Px, T-AOC, LPO) and collagen fibers. The relative expression levels of genes (VEGF and miRNA21) in the CPNP microcapsules group were higher than those in the model group and the negative group. The above results suggested that the CPNP microcapsules could controlled-release the CPNP to the wound surface, and then played a better role in antibacterial, anti-inflammatory and skin wound repair.

Nephroprotective activity of Aframomum melegueta seeds extract against diclofenac-induced acute kidney injury: A mechanistic study

ETHNOPHARMACOLOGICAL RELEVANCE

In Africa, Aframomum species have been traditionally used to treat illnesses such as inflammation, hypertension, diarrhea, stomachache and fever. Moreover, Aframomum melegueta seed extracts (AMSE) are used in traditional medicine to relieve stomachaches and inflammatory diseases.

AIM

Chronic administration of diclofenac (DIC) has been reported to cause acute kidney injury (AKI), which is a serious health condition. The nephroprotective effect of AMSE is yet to be elucidated. Accordingly, this study aims to investigate the phytoconstituents of standardized AMSE, evaluate its nephroprotective effects against DIC-induced AKI in rats, and elaborate its underlying molecular mechanisms.

MATERIALS AND METHODS

The quantitative estimation of major AMSE constituents and profiling of its secondary metabolites were conducted via RP-HPLC and LC-ESI/Triple TOF/MS, respectively. Next, DIC (50 mg/kg)-induced AKI was achieved in Sprague-Dawley rats and DIC-challenged rats were administered AMSE (100 and 200 mg/kg) orally. All treatments were administered for five consecutive days. Blood samples were collected and the sera were used for estimating creatinine, urea and, kidney injury molecule (KIM)-1 levels. Kidney specimens were histopathologically assessed and immunohistochemically examined for c-Myc expression. A portion of the kidney tissue was homogenized and examined for levels of oxidative stress markers (MDA and GSH). Heme oxygenase (HO)-1, TNF-α, IL-6, Bax, Bcl2 and caspase-3 renal levels were quantified by ELISA. Moreover, the protein expression levels of NF-ҡB p65 was quantified using Western blot analysis, whereas mRNA expression levels of AMPK, SIRT-1, nuclear factor erythroid-2-related factor (Nrf2) and STAT3 were detected using qRT-PCR in the remaining kidney tissues.

RESULTS

Standardized AMSE was shown to primarily contain 6-gingerol, 6-shogaol and 6-paradol among the 73 compounds that were detected via LC-ESI/Triple TOF/MS including phenolic acids, hydroxyphenylalkanes, diarylheptanoids and fatty acids. Relative to DIC-intoxicated rats, AMSE modulated serum creatinine, urea, KIM-1, renal MDA, TNF-α, IL-6, Bax, and caspase-3 levels. AMSE has also improved renal tissue architecture, enhanced GSH and HO-1 levels, and upregulated renal Nrf2, AMPK, and SIRT-1 mRNA expression levels. Furthermore, AMSE suppressed NF-ҡB p65 protein and STAT3 mRNA expression, and further reduced c-Myc immunohistochemical expression in renal tissues. Overall, our findings revealed that AMSE counteracted DIC-induced AKI via its antioxidant, anti-inflammatory, and antiapoptotic activities. Moreover, AMSE activated Nrf2/HO1 and AMPK/SIRT1, and inhibited NF-ҡB/STAT3 signaling pathways. Therefore, AMSE is a promising agent for inhibiting DIC-induced nephrotoxicity.

Jararhagin, a snake venom metalloproteinase, induces mechanical hyperalgesia in mice with the neuroinflammatory contribution of spinal cord microglia and astrocytes

Jararhagin is a hyperalgesic metalloproteinase from Bothrops jararaca venom. In rodents, jararhagin induces nociceptive behaviors that correlate with an increase in peripheral cytokine levels. However, the role of the spinal cord glia in pain processing after peripheral stimulus of jararhagin has not been investigated. Aiming to explore this proposal, mice received intraplantar (i.pl.) injection of jararhagin and the following parameters were evaluated: hyperalgesia, spinal cord TNF-α, IL-1β levels, and CX3CR1, GFAP and p-NFκB activation. The effects of intrathecal (i.t.) injection of TNF-α soluble receptor (etanercept), IL-1 receptor antagonist (IL-1Ra), and inhibitors of NFκB (PDTC), microglia (minocycline) and astrocytes (α-aminoadipate) were investigated. Jararhagin inoculation induced cytokine production (TNF-α and IL-1β) in the spinal cord, which was reduced by treatment with PDTC (40% and 50%, respectively). Jararhagin mechanical hyperalgesia and cytokine production were inhibited by treatment with etanercept (67%), IL-1Ra (60%), PDTC (70%), minocycline (60%) and α-aminoadipate (45%). Furthermore, jararhagin induced an increase in p-NFκB, CX3CR1 and GFAP detection in the spinal cord indicating activation of NFκB, microglia and astrocytes. These results demonstrate for the first time that jararhagin-induced mechanical hyperalgesia is dependent on spinal cord activation of glial cells, consequent NFκB activation, and cytokine production in mice.

New insight into the effect of lycopene on the oxidative stress in acute kidney injury

Objective:

To evaluate the nephroprotective effect of lycopene (LPN) in acute kidney injury (AKI) regarding the oxidative stress (OS).

Materials and Methods:

Thirty Sprague Dawley male rats were divided into three groups – control group: rats treated with distilled water (orally) for 10 days (n = 10); AKI group: rats treated with distilled water and diclofenac (intraperitoneal) for 10 days (n = 10); treated group: rats treated with LPN (orally) and diclofenac for 10 days (n = 10). Body mass index (BMI) and estimated glomerular filtration rate (eGFR) were measured. Blood urea, serum creatinine (CreSerum), serum malondialdehyde (MDA), superoxide dismutase (SOD), neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury molecules (KIM-1) were measured in the all groups on the 11^th day of the experiment.

Results:

Diclofenac-induced AKI led to significant elevations of BMI, CreSerum, and blood urea compared with control (P < 0.05). In AKI model, eGFR was reduced to 11.69 ± 2.64 ml/min/1.73 compared with control group (15.88 ± 3.75 ml/min/1.73, P = 0.03). NGAL, MDA, and KIM-1 were elevated in AKI compared with control (P < 0.001). Pretreatment with LPN led to the reduction of blood urea and CreSerum as compared with AKI (P < 0.001). Similarly, eGFR was increased significantly to 14.81 ± 3.21 ml/min/1.73 compared with 11.69 ± 2.64 ml/min/1.73 in AKI (P = 0.02). Serum levels of NGAL, KIM-1, and MDA were reduced significantly in the LPN group as compared with AKI (P = 0.001), while the SOD serum level was increased to 33. 86 ± 8.61 pg/ml as compared to 22.78 ± 7.56 pg/ml in AKI (P = 0.006). As well, LPN reduced MDA/SOD ratio as compared with AKI (P = 0.00001).

Conclusion:

The finding of this study illustrated that LPN is an effective natural antioxidant that attenuates and prevents AKI through modulation of OS and lipid peroxidation. As well, LPN might be of great value in the prevention of nephrotoxicity that induced by nephrotoxic agents like diclofenac.

Gas Chromatographic and Spectrophotometric Determination of Diclofenac Sodium, Ibuprofen, and Mefenamic Acid in Urine and Blood Samples

Objectives

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for the treatment of acute to chronic pain. A simple, fast, and reliable gas chromatographic (GC) method with flame ionization detection has been developed for the determination of NSAIDs such as diclofenac sodium, ibuprofen, and mefenamic acid after derivatization with ethyl chloroformate.

Materials and Methods

The GC conditions were optimized as elution from a DB-1 column (30 mx0.32 mm id) at column temperature 150 °C for 3 min, followed by a heating rate of 20 °C/min up to 280 °C and a hold time of 5 min. The nitrogen flow rate was 2.5 mL/min. For spectrophotometric studies, the absorbance was measured against methanol at a wavelength of 200-500 nm.

Results

The calibration curves were linear within 2-10 μg/mL with limits of detection of 0.4-0.6 μg/mL of each drug. The derivatization elution, separation, and quantitation were repeatable (n=3) with relative standard deviation (RSD) within 3.9%. The method was applied for the analysis of the drugs from pharmaceutical formulations and the results of the analysis agreed with labeled values with RSDs within 0.5-3.9%. The results were also confirmed by standard addition method. The percent recovery was calculated with spiked deproteinized human blood serum and urine samples and % recovery of the drugs was obtained within 96-98% with RSDs within 3.1%.

Conclusion

The validated method proved its ability for the assay of NSAIDs in bulk and dosage form in a short analysis time. The method was also useful for the analysis of biological samples.

Role of TLR4/MyD88/NF-κB signaling in the contrast-induced injury of renal tubular epithelial cells

The aim of the present study was to explore the role of toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factor (NF)-κB signaling in the contrast-induced injury of renal tubular epithelial cells, and to investigate the potential mechanisms. HK-2 cells cultured in vitro were randomly divided into six groups as follows: i) The blank group; ii) the iohexol group; iii) the NF-κB RNAi group (NF-κB siRNA + iohexol); iv) the TLR4 RNAi group (TLR4 siRNA + iohexol); v) the NF-κB blocker group (PDTC + iohexol); and vi) the TLR4 blocker group (CLI-095 + iohexol). The expression of the TLR4/MyD88/NF-κB signaling pathway proteins was detected by reverse transcription-quantitative (RT-q)PCR and western blot analysis, and the cellular proliferation rate was determined using the Cell Counting Kit-8 assay. The mRNA expression levels of the inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 were also detected using RT-qPCR, and apoptosis was assessed by flow cytometry and western blotting to detect apoptosis-associated proteins (caspase-3, caspase-9 and cleaved caspase-9). Compared with the blank group, the apoptotic rates and the expression levels of TLR4, MyD88, NF-κB, caspase-3, cleaved caspase-9, TNF-α, IL-1β and IL-6 were upregulated in the iohexol group (P<0.001). However, when TLR4 or NF-κB were blocked or silenced, these effects were reversed (P<0.001). Collectively, the results of the present study indicated that TLR4/MyD88/NF-κB signaling is involved in the contrast-induced injury of renal tubular epithelial cells by inducing inflammation and apoptosis.

Evaluation of hepatic and renal effects in rat dams and their offspring after exposure to paracetamol during gestation and lactation

Paracetamol (PAR) is the analgesic and antipyretic of choice for pregnant and nursing women. PAR may reach the fetus and/or neonate through the placenta and/or milk and effect development. This study evaluated possible hepatic and renal effects in rat dams and their offspring exposed to PAR using a human-relevant route of administration and doses from Gestational Day 6 to Postnatal Day (PND) 21. Dams were gavaged daily with PAR (35 or 350mg kg-1) or water (CON). Dams and pups were killed on PND21 and 22 respectively, and blood was collected for biochemical analysis (aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea and creatinine). The kidneys and liver were isolated and processed for histopathological assessment and evaluation of oxidative stress markers. Compared with the CON groups, pups exposed to 350mg kg-1 PAR had increased renal reduced glutathione (GSH), whereas dams exposed to both doses of PAR increased serum AST. PAR administration did not affect parameters of general toxicity or renal and hepatic oxidative stress. In conclusion, maternal exposure to human-relevant doses of PAR by gavage was not associated with hepatic or renal toxicity in the pups or dams, but PAR was not devoid of effects. Exposure to PAR increased renal GSH in pups, which could suggest an adaptive antioxidant response, and affected maternal serum AST activity.

Protective effect of pyrrolidine dithiocarbamate on isoniazid/rifampicin‑induced liver injury in rats

Isoniazid (INH) and rifampicin (RIF) continue to be first line anti‑tuberculosis (TB) drugs. However, the use of these drugs is associated with hepatotoxicity. Nuclear factor‑κB (NF‑κB) plays a crucial role in regulating immunity and inflammation. It has been reported that pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF‑κB, exerts a hepatoprotective effect on acute and chronic liver damage. The aim of the present study was to explore the INH/RIF‑induced protective effects and mechanisms of PDTC on liver injury. Rats were intragastrically administered INH (50 mg/kg/day) and RIF (50 mg/kg/day) daily for 28 days. PDTC (50 mg/kg/day) was intraperitoneally injected 2 h after the co‑administration of INH and RIF to compare liver biochemical indicators in the serum, histopathological damage, NF‑κB activity, oxidative stress, hepatic mRNA expression of tumor necrosis factor (TNF)‑α, bile salt export pump (BSEP), and protein expression of BSEP. It was found that the inhibition of NF‑κB activation by PDTC treatment markedly alleviated liver biochemical and histological injury, decreased oxidative stress and mRNA levels of TNF‑α, and prevented decreases in BSEP mRNA and protein expression induced by the co‑administration of INH and RIF. Collectively, the present data suggested that INH/RIF‑induced liver injury is dependent on the activation of NF‑κB. PDTC exerted a therapeutic effect on INH/RIF‑induced liver injury by increasing BSEP expression, and exhibiting antioxidant and anti‑inflammatory activities.

Nephroprotective effect of silymarin against diclofenac induced renal damage and oxidative stress in male rats

Introduction: Diclofenac (DIC), a phenylacetic acid compound which belongs to nonsteroidal anti-inflammatory drugs (NSAIDs), is generally used for the treatment of various diseases such as rheumatoid arthritis, ankylosing spondylitis, acute muscle pain conditions and osteoarthritis. Overdose of DIC can lead to renal injuries in both experimental animal and human. Our research was done to assess the protective role of silymarin on renal damage induced by DIC in rats. Methods: Thirty-two Wistar rats were assigned to four groups (n=8/group). Group 1 was control group; animals in group 2 were administrated DIC; Groups 3 and 4 administrated DIC plus silymarin with doses of 100 mg/kg and 200 mg/kg, orally (p.o), respectively. Various biochemical, molecular, and histological parameters were evaluated in serum and tissue homogenate. Results: In the second group, the levels of kidney catalase (CAT), vitamin C and superoxide dismutase (SOD) remarkably reduced (P < 0.05) relative to the control group. Also, urea, creatinine (Cr), malondialdehyde (MDA), serum tumor necrosis factor-α (TNF-α) and gene expression of TNF-α in this group were noticeably elevated (P < 0.05) relative to the control group. Treatment with silymarin caused a remarkable elevation (P < 0.05) in vitamin C, SOD, CAT and a remarkable reduction (P < 0.05) in the content of MDA, urea, Cr, TNF-α gene expression and serum TNF-α in comparison with second group. Histological injuries were also ameliorated by silymarin administration. Conclusion: The results confirm that silymarin has an ameliorative role against renal damage and oxidative stress induced by DIC in male rats.

Magnetic polyethyleneimine functionalized reduced graphene oxide as a novel magnetic sorbent for the separation of polar non-steroidal anti-inflammatory drugs in waters

A novel magnetic polyethyleneimine modified reduced graphene oxide (Fe₃O₄@PEI-RGO) had been prepared and then was successfully employed to extract three polar non-steroidal anti-inflammatory drugs (NSAIDs) in different water matrices for the first time coupled with high performance liquid chromatography-diode array detector (HPLC-DAD). The magnetic polyethyleneimine (Fe₃O₄@PEI) composite was first synthesized via one-pot hydrothermal approach and then the Fe₃O₄@PEI-RGO composite was fabricated on the basis of a simple self-assemble approach between positive charged Fe₃O₄@PEI and negative charged GO sheets via electrostatic interaction followed by chemical reduction of GO to RGO. The as-prepared Fe₃O₄@PEI-RGO composite was carefully characterized by transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FT-IR), X-ray diffraction (XRD), thermal gravimetric analyzer (TGA), vibrating sample magnetometer (VSM) and zeta potential analysis. As a surface modifier of RGO, PEI not just changed the polarity of RGO to some extent but also offered more adsorption sites to polar NSAIDs. Compared with Fe₃O₄@PEI, Fe₃O₄-RGO and Fe₃O₄@PEI-GO, the as-prepared Fe₃O₄@PEI-RGO composite, which combined the advantage of PEI and RGO, showed higher extraction efficiency for polar NSAIDs. In addition, the adsorption mechanism was also studied. The analytical parameters influencing the extraction efficiency were optimized in detail. A satisfactory performance was obtained under the optimal conditions. The calibration lines were linear over the concentration in the range of 1-800 μg L^-1 for all the analytes with determination coefficients (r²) varying from 0.9972 to 0.9986. The limits of detection (LODs) were 0.2 μg L^-1. The recoveries were between 91.20% and 101.13% with relative standard deviations (RSDs) in the range of 1.09-7.34%. Overall, a fast, convenient, sensitive and eco-friendly method was successfully proposed and became a promising approach for the determination of trace polar NSAIDs in complex matrices.