Protective effects of edaravone, a free radical scavenger, on lipopolysaccharide-induced acute kidney injury in a rat model of sepsis

Alirocumab boosts antioxidant status and halts inflammation in rat model of sepsis-induced nephrotoxicity via modulation of Nrf2/HO-1, PCSK9/HMGB1/NF-ᴋB/NLRP3 and Fractalkine/CX3CR1 hubs

Acute kidney injury (AKI) is a devastating consequence of sepsis, accompanied by high mortality rates. It was suggested that inflammatory pathways are closely linked to the pathogenesis of lipopolysaccharide (LPS)-induced AKI. Inflammatory signaling, including PCSK9, HMGB1/RAGE/TLR4/MYD88/NF-κB, NLRP3/caspase-1 and Fractalkine/CX3CR1 are considered major forerunners in this link. Alirocumab, PCSK9 inhibitor, with remarkable anti-inflammatory features. Accordingly, this study aimed to elucidate the antibacterial effect of alirocumab against E. coli in vitro. Additionally, evaluation of the potential nephroprotective effects of alirocumab against LPS-induced AKI in rats, highlighting the potential underlying mechanisms involved in these beneficial actions. Thirty-six adult male Wistar rats were assorted into three groups (n=12). Group I; was a normal control group, whereas sepsis-mediated AKI was induced in groups II and III through single-dose intraperitoneal injection of LPS on day 16. In group III, animals were given alirocumab. The results revealed that LPS-induced AKI was mitigated by alirocumab, evidenced by amelioration in renal function tests (creatinine, cystatin C, KIM-1, and NGAL); oxidative stress biomarkers (Nrf2, HO-1, TAC, and MDA); apoptotic markers and renal histopathological findings. Besides, alirocumab pronouncedly hindered LPS-mediated inflammatory response, confirmed by diminishing HMGB1, TNF-α, IL-1β, and caspase-1 contents; the gene expression of PCSK9, RAGE, NF-ᴋB and Fractalkine/CX3CR1, along with mRNA expression of TLR4, MYD88, and NLRP3. Regarding the antibacterial actions, results showed that alirocumab displayed potential anti-bacterial activity against pathogenic gram-negative E. coli. In conclusion, alirocumab elicited nephroprotective activities against LPS-induced AKI via modulation of Nrf2/HO-1, PCSK9, HMGB1/RAGE/TLR4/MYD88/NF-ᴋB/NLRP3/Caspase-1, Fractalkine/CX3R1 and apoptotic axes.

Sorafenib and edaravone protect against renal fibrosis induced by unilateral ureteral obstruction via inhibition of oxidative stress, inflammation, and RIPK-3/MLKL pathway

Renal fibrosis is the common endpoint of nearly all chronic and progressive nephropathies. Cell death and sterile inflammation are the main characteristics of renal fibrosis, which can lead to end-stage renal failure. The inflammatory reaction triggered by tissue damage is strongly related to necroptosis, a type of caspase-independent, regulated cell death. Using an animal model of unilateral ureteral obstruction (UUO), the anti-fibrotic effects of sorafenib (SOF), a multi-kinase inhibitor, and edaravone (EDV), a potent antioxidant and free radical scavenger, were examined in rats with obstructive nephropathy. Experimentally, animals were divided randomly into five groups: sham; UUO; UUO + SOF (5 mg/kg/day, P.O.); UUO + EDV (20 mg/kg/day, P.O.); and UUO + SOF + EDV groups. The kidney function biomarkers, oxidant/antioxidant status, renal mRNA expressions of TNF-α, collagen-1α, protein expressions of RIPK-1, RIPK-3, MLKL, caspase-8, HYP, MPO, and TNF-α were all significantly modulated by UUO. Administration of either SOF or EDV significantly attenuated cellular and molecular changes induced by UUO. Also, histopathological changes were improved. Moreover, SOF in combination with EDV, significantly improved UUO-induced renal fibrosis compared with each drug alone. Collectively, administration of either SOF or EDV or both of them significantly attenuated the rats with obstructive nephropathy, possibly by blocking the RIPK-3/MLKL necroptotic pathway and suppressing renal oxidative stress and inflammation.

Edaravone-loaded poly(amino acid) nanogel inhibits ferroptosis for neuroprotection in cerebral ischemia injury

Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulation half-life and poor blood-brain barrier (BBB) permeability. For that, an edaravone-loaded pH/glutathione (pH/GSH) dual-responsive poly(amino acid) nanogel (NG/EDA) was developed to improve the neuroprotection of EDA. The nanogel was triggered by acidic and EDA-induced high-level GSH microenvironments, which enabled the selective and sustained release of EDA at the site of ischemic injury. NG/EDA exhibited a uniform sub-spherical morphology with a mean hydrodynamic diameter of 112.3 ± 8.2 nm. NG/EDA efficiently accumulated at the cerebral ischemic injury site of permanent middle cerebral artery occlusion (pMCAO) mice, showing an efficient BBB crossing feature. Notably, NG/EDA with 50 µM EDA significantly increased neuron survival (29.3%) following oxygen and glucose deprivation by inhibiting ferroptosis. In addition, administering NG/EDA for 7 d significantly reduced infarct volume to 22.2% ± 7.2% and decreased neurobehavioral scores from 9.0 ± 0.6 to 2.0 ± 0.8. Such a pH/GSH dual-responsive nanoplatform might provide a unique and promising modality for neuroprotection in ischemic stroke and other central nervous system diseases.

Protective effect of pregabalin on renal and renal endothelial damage in sepsis induced by lipopolysaccharide

OBJECTIVE

We investigated the protective effects of pregabalin (PRG) on kidney and renal endothelial damage in sepsis induced by Lipopolysaccharide (LPS).

MATERIALS AND METHODS

Rats were randomly divided into three groups as control, LPS and LPS+PRG. Saline solution was administered 30 mg/kg orally and 5 mg/kg intraperitoneally (i.p.) to the control group. LPS was applied as 5 mg/kg, i.p. to the LPS group. In the LPS+PRG group, PRG at 30 mg/kg orally and one hour before LPS administration, one hour later 5 mg/kg i.p. LPS was applied. Rats were sacrificed 6 hours after LPS administration.

RESULTS

White Blood Cell (WBC), granulocyte, Blood Urea Nitrogen (BUN), creatinine, uric asid, Total Oxidant Status (TOS) and Oxidative Stress Index (OSI) significantly increased (p<0.05); platelets (PLT), activated partial thromboplastin time (aPTT) and Total Antioxidant Status (TAS) significantly decreased in the LPS group compared to the control group (p<0.05). In the LPS+PRG group WBC, granulocyte, BUN, creatinine, uric asid, TOS and OSI significantly decreased (p<0.05); PLT, aPTT and TAS significantly increased compared to the LPS group(p<0.05). Histopathological examinations showed that kidney and renal endothelial damage in the LPS group decreased in the LPS+PRG group. Immunohistochemically IL1-β, IL-6, IL-10, TNF-α expressions in kidney tissue and Toll-Like Receptors-4 (TLR-4) and NF-κB expressions in the renal endothelial tissue significantly increased in the LPS group compared to the control group and significantly decreased in the LPS+PRG group compared to the LPS group (p<0.001).

CONCLUSIONS

Sepsis causes kidney and renal endothelial damage and PRG reduces this damage. Therefore PRG can be used in prophylactic treatment in sepsis, supported by more studies.

Natural ursolic acid based self-therapeutic polymer as nanocarrier to deliver natural resveratrol for natural therapy of acute kidney injury

Acute kidney injury (AKI) is a common kidney disease associated with excessive reactive oxygen species (ROS). Unfortunately, due to the low kidney targeting and undesired side effects, the existing antioxidant and anti-inflammatory drugs are unavailable for AKI management in clinic. Therefore, it's essential to develop effective nanodrugs with high renal targeting and biocompatibility for AKI treatment. Herein, we reported a novel nanodrug for AKI treatment, utilizing poly(ursolic acid) (PUA) as a bioactive nanocarrier and resveratrol (RES) as a model drug. The PUA polymer was synthesized form ursolic acid with intrinsic antioxidant and anti-inflammatory activities, and successfully encapsulated RES through a nanoprecipitation method. Subsequently, we systemically investigated the therapeutic potential of RES-loaded PUA nanoparticles (PUA NPs@RES) against AKI. In vitro results demonstrated that PUA NPs@RES effectively scavenged ROS and provided substantial protection against H2O2-induced cellular damage. In vivo studies revealed that PUA NPs significantly improved drug accumulation in the kidneys and exhibited favorable biocompatibility. Furthermore, PUA NPs alone exhibited additional anti-inflammatory and antioxidant effect, synergistically enhancing therapeutic efficacy in AKI mouse models when combined with RES. Overall, our study successfully developed an effective nanodrug using self-therapeutic nanocarriers, presenting a promising option for the treatment of AKI.

Animal Models of Kidney Disease: Challenges and Perspectives

Kidney disease is highly prevalent and affects approximately 850 million people worldwide. It is also associated with high morbidity and mortality, and current therapies are incurable and often ineffective. Animal models are indispensable for understanding the pathophysiology of various kidney diseases and for preclinically testing novel remedies. In the last two decades, rodents continue to be the most used models for imitating human kidney diseases, largely because of the increasing availability of many unique genetically modified mice. Despite many limitations and pitfalls, animal models play an essential and irreplaceable role in gaining novel insights into the mechanisms, pathologies, and therapeutic targets of kidney disease. In this review, we highlight commonly used animal models of kidney diseases by focusing on experimental AKI, CKD, and diabetic kidney disease. We briefly summarize the pathological characteristics, advantages, and drawbacks of some widely used models. Emerging animal models such as mini pig, salamander, zebrafish, and drosophila, as well as human-derived kidney organoids and kidney-on-a-chip are also discussed. Undoubtedly, careful selection and utilization of appropriate animal models is of vital importance in deciphering the mechanisms underlying nephropathies and evaluating the efficacy of new treatment options. Such studies will provide a solid foundation for future diagnosis, prevention, and treatment of human kidney diseases.

The Role of Ketone Bodies in Various Animal Models of Kidney Disease

The kidney is a vital organ that carries out significant metabolic functions in our body. Due to the complexity of its role, the kidney is also susceptible to many disease conditions, such as acute kidney injury (AKI) and chronic kidney disease (CKD). Despite the prevalence and our increased understanding of the pathophysiology of both AKI and CKD as well as the transition of AKI to CKD, no well-established therapeutics have been applied clinically to these conditions, rendering an urgent need for a novel potential therapeutic target to be developed. In this article, we reviewed the function of ketone bodies in some common kidney conditions, such as drug-induced nephrotoxicity, ischemia and reperfusion injury, fibrosis development, diabetic kidney disease, kidney aging, hypertension, and CKD progression. All the selected studies reviewed were performed in animal models by primarily utilizing rodents, which also provide invaluable sources for future clinical applications. Ketone bodies have shown significant renal protective properties via attenuation of oxidative stress, increased expression of anti-inflammatory proteins, gene regulation, and a reduction of apoptosis of renal cells. A physiological level of ketone bodies could be achieved by fasting, a ketogenic diet, and an exogenous ketone supplement. Finally, the limitations of the long-term ketogenic diet were also discussed.

ADENOSINE MONOPHOSPHATE-ACTIVATED PROTEIN KINASE PHOSPHORYLATION MEDIATED BY SIRTUIN 5 ALLEVIATES SEPTIC ACUTE KIDNEY INJURY

ABSTRACT

Background : Our previous studies have shown that ameliorating mitochondrial damage in renal tubular epithelial cells (RTECs) can alleviate septic acute kidney injury (SAKI). It is reported that AMPK phosphorylation (p-AMPK) could ameliorate mitochondrial damage in renal tissue and Sirtuin 5 (SIRT5) overexpression significantly enhanced the level of p-AMPK in bovine preadipocytes. However, the role of SIRT5-mediated phosphorylation of AMPK in SAKI needs to be clarified. Methods : WT/SIRT5 gene knockout mouse model of cecal ligation and puncture-induced SAKI and a human kidney 2 cell model of LPS-induced SAKI were constructed. An AMPK chemical activator and SIRT5 overexpression plasmid were used. Indexes of mitochondrial structure and function, level of p-AMPK, and expression of SIRT5 protein in renal tissue and RTECs were measured. Results : After sepsis stimulation, the p-AMPK level was decreased, mitochondrial structure was disrupted, and ATP content was decreased. Notably, an AMPK activator alleviated SAKI. Sirtuin 5 gene knockout significantly aggravated SAKI, while SIRT5 overexpression alleviated mitochondrial dysfunction after LPS stimulation, as manifested by the increase of p-AMPK level, the alleviation of mitochondrial structure damage, the restoration of ATP content, the decrease of proapoptotic protein expression, as well as the reduction of reactive oxygen species generation. Conclusions : Upregulation of SIRT5 expression can attenuate mitochondrial dysfunction in RTECs and alleviate SAKI by enhancing the phosphorylation of AMPK.

Protective Effect of Silymarin on Liver in Experimental in the Sepsis Model of Rats

This study, it was investigated whether silymarin has a protective effect by performing histological, immunohistochemical, and biochemical evaluations on the liver damage induced by cecal ligation perforation (CLP). CLP model was established and silymarin was treated at a dose of 50 mg/kg, 100 mg/kg, and 200 mg/kg, by oral one hour before the CLP. As an effect of the histological evaluations of the liver tissues, venous congestion, inflammation, and necrosis in the hepatocytes were observed in the CLP group. A situation close to the control group was observed in the Silymarin (SM)100 and SM200 groups. As a result of the immunohistochemical evaluations, inducible nitric oxide synthase (iNOS), cytokeratine (CK)18, Tumor necrosis factor-alpha (TNF-α), and interleukine (IL)-6 immunoreactivities were intense in the CLP group. In the biochemical analysis, Alkaline Phosphatase (ALP), Aspartate Aminotransferase (AST), and Alanine Aminotransferase (ALT) levels were significantly increased in the CLP group, while a significant decrease was observed in the treatment groups. TNFα, IL-1β, and IL-6 concentrations were in parallel with histopathological evaluations. In the biochemical analysis, Malondialdehyte (MDA) level increased significantly in the CLP group, but there was a significant decrease in the SM100 and SM200 groups. Glutathione (GSH), Superoxide Dismutase (SOD), Catalase (CAT), and Glutathione Peroxidase (GSH-Px) activities were relatively low in the CLP group. According to these data, it was concluded that using silymarin reduces the existing liver damage in sepsis.

Hydrogenated Germanene Nanosheets as an Antioxidative Defense Agent for Acute Kidney Injury Treatment

Acute kidney injury (AKI) is a sudden kidney dysfunction caused by aberrant reactive oxygen species (ROS) metabolism that results in high clinical mortality. The rapid development of ROS scavengers provides new opportunities for AKI treatment. Herein, the use of hydrogen-terminated germanene (H-germanene) nanosheets is reported as an antioxidative defense nanoplatform against AKI in mice. The simulation results show that 2D H-germanene can effectively scavenge ROS through free radical adsorption and subsequent redox reactions. In particular, the H-germanene exhibits high accumulation in injured kidneys, thereby offering a favorable opportunity for treating renal diseases. In the glycerol-induced murine AKI model, H-germanene delivers robust antioxidative protection against ROS attack to maintain normal kidney function indicators without negative influence in vivo. This positive in vivo antioxidative defense in living animals demonstrates that the present H-germanene nanoplatform is a powerful antioxidant against AKI and various anti-inflammatory diseases.

Hydrogenated Germanene Nanosheets as an Antioxidative Defense Agent for Acute Kidney Injury Treatment

Acute kidney injury (AKI) is a sudden kidney dysfunction caused by aberrant reactive oxygen species (ROS) metabolism that results in high clinical mortality. The rapid development of ROS scavengers provides new opportunities for AKI treatment. Herein, the use of hydrogen‐terminated germanene (H‐germanene) nanosheets is reported as an antioxidative defense nanoplatform against AKI in mice. The simulation results show that 2D H‐germanene can effectively scavenge ROS through free radical adsorption and subsequent redox reactions. In particular, the H‐germanene exhibits high accumulation in injured kidneys, thereby offering a favorable opportunity for treating renal diseases. In the glycerol‐induced murine AKI model, H‐germanene delivers robust antioxidative protection against ROS attack to maintain normal kidney function indicators without negative influence in vivo. This positive in vivo antioxidative defense in living animals demonstrates that the present H‐germanene nanoplatform is a powerful antioxidant against AKI and various anti‐inflammatory diseases.

Exploring the effects of edaravone in rats with contrast-induced acute kidney injury

AIMS

Oxidative stress and inflammatory response play a vital role in the pathogenesis of contrast-induced acute kidney injury (CI-AKI). This study investigated the effects of edaravone in rats with CI-AKI.

MAIN METHODS

Male Sprague Dawley rats were randomly assigned into four groups (n = 11-14/group): control, edaravone (30 mg/kg/day intraperitoneally (IP)), CI-AKI, and edaravone with CI-AKI. The induction of CI-AKI was performed by dehydration and the administration of contrast media (iohexol) and inhibitors of prostaglandin (indomethacin) and nitric oxide synthesis (L-NAME: N-nitro L-arginine methyl ester). Edaravone was administered for two weeks before the induction of CI-AKI. Serum creatinine and urea, renal oxidative stress and inflammatory biomarkers, and histopathological alterations were evaluated after 48 h of contrast exposure.

KEY FINDINGS

Rats with CI-AKI showed a significant increase in serum creatinine and urea. The levels of antioxidant biomarkers including glutathione peroxidase, superoxide dismutase and reduced glutathione were significantly decreased in CI-AKI group versus control. Pre-treatment of rats with edaravone normalized kidney function and protected the kidney from oxidative damage as demonstrated by normalization of previous biomarkers. Furthermore, edaravone partially ameliorated renal histopathological alterations relative to the CI-AKI group, notably in the nephrons. No changes were observed in inflammatory biomarkers including tumour necrosis factor-alpha and interleukin-6 among all groups.

SIGNIFICANCE

The current findings suggest that edaravone could be a potential strategy to ameliorate developing CI-AKI possibly by improving renal antioxidant capacity. Further studies are warranted to expand the current understanding of the use of edaravone in the various models of AKI.

Renal safety evaluation of aspirin plus edaravone in patients with ischaemic stroke: a retrospective cohort study

BACKGROUND AND OBJECTIVE

Aspirin combined with edaravone is more effective than aspirin or edaravone alone in the treatment of ischaemic stroke. Aspirin is defined as a nephrotoxic drug while the renal safety of edaravone is controversial. We aimed to evaluate whether edaravone will increase the nephrotoxicity of aspirin in patients with ischaemic stroke.

DESIGN

A propensity score-matched retrospective cohort study.

SETTING

A tertiary hospital in China.

PARTICIPANTS

Patients with ischaemic stroke were treated with aspirin from February 2007 to May 2018.

PRIMARY AND SECONDARY OUTCOME MEASURES

Acute kidney injury (AKI, diagnosed by the Acute Kidney Injury Network), decreased estimated glomerular filtration rate (eGFR,>10%), gastrointestinal bleeding and in-hospital adverse outcomes (defined as dying or giving up treatment in our hospital).

RESULTS

We included 3061 patients, and 986 pairs were successfully matched. Of the 986 pairs of patients included, the incidence of AKI between the aspirin group and the combination group showed no significant difference (7.71% vs 6.29%, p=0.217). While the incidence of eGFR decline (24.75% vs 16.94%, p<0.001) was significantly lower in the combination group. The protective effect was significant in patients with baseline eGFR >30 mL/min/1.73 m², especially in eGFR 60-90 mL/min/1.73 m². In patients with different complications, the incidence of AKI showed no significant differences in patients with chronic kidney injury, hypertension, anaemia, age above 75 years, except in patients with cardiovascular disease (OR, 2.82; 95% CI 1.50 to 5.29; p<0.001). However, the incidence of gastrointestinal bleeding (1.22% vs 2.84%, p=0.011) and in-hospital adverse outcomes (3.25% vs 7.00%, p<0.001) were significantly higher in the combination group.

CONCLUSIONS

Our study indicated that edaravone in patients with ischaemic stroke didn't increase the nephrotoxicity of aspirin, and even had a protective effect on mild renal deterioration. Nevertheless, there is a need to be cautious when patients are in bad pathophysiological conditions and at high risk of bleeding.

Mesenchymal stem cells microvesicles versus granulocytes colony stimulating factor efficacy in ameliorating septic induced acute renal cortical injury in adult male albino rats (Histological and Immunohistochemical Study)

Sepsis is the most common cause of acute kidney injury in ICU patients, with increasing mortalities. Treatment septic AKI is unsatisfactory; therefore, more effective therapies must be investigated. MSCs-MVs have the same effectiveness in tissue repair as their original cells. Granulocyte colony-stimulating factor (G-CSF) is considered a simple and convenient tool in regenerative medicine. This study aimed to compare the probable therapeutic effect of MSCs-MVs versus G-CSF on septic AKI in rats. Forty-eight adult male rats were divided into four groups; I control group (IA-ID), II induced-sepsis group, III G-CSF, and IV MSC-MVs groups. Sepsis was induced in groups II, III, IV through a single IV injection of 10 mg/ kg of E.Coli-LPS dissolved in 1 ml saline. Four hours later, group IV received a single IV injection of MSCs-MVs, while group III received a SC injection of Neupogen for 5 days. All animals were sacrificed 7 days from the start. Serum and tissue samples of each group were used for biochemical study. Sections from all groups were subjected to light and electron microscopic examination. A fluorescent microscope examination for subgroup ID and group IV was done. Morphometric and statistical analyses were performed. Group II showed features of acute tubular injury. Group III showed some improvement (biochemically, LM & EM level) however, group IV showed more improvement. MVs injection caused a marked improvement in septic AKI; G-CSF can also meliorate the degenerative effect of sepsis on renal cortex, but to a lesser extent than MSCs-MVs.

Effects of the Edaravone, a Drug Approved for the Treatment of Amyotrophic Lateral Sclerosis, on Mitochondrial Function and Neuroprotection

Edaravone, the first known free radical scavenger, has demonstrated cellular protective properties in animals and humans. Owing to its antioxidant activity, edaravone modulates oxidative damage in various diseases, especially neurodegenerative diseases. In 2015, edaravone was approved in Japan to treat amyotrophic lateral sclerosis. The distinguishing pathogenic features of neurodegenerative diseases include high reactive oxygen species levels and mitochondrial dysfunction. However, the correlation between mitochondria and edaravone has not been elucidated. This review highlights recent studies on novel therapeutic perspectives of edaravone in terms of its effect on oxidative stress and mitochondrial function.

Potent efficacy of Stachybotrys microspora triprenyl phenol-7, a small molecule having anti-inflammatory and antioxidant activities, in a mouse model of acute kidney injury

Acute kidney injury (AKI) increases the risk of chronic kidney disease (CKD), complicates existing CKD, and can lead to the end-stage renal disease. However, there are no approved effective therapeutics for AKI. Recent studies have suggested that inflammation and oxidative stress are the primary causes of AKI. We previously reported the potential anti-inflammatory and antioxidant activities of Stachybotrys microspora triprenyl phenol-7 (SMTP-7). The aim of the present study was to evaluate the efficacy of SMTP-7 in AKI model mice. AKI was induced in mice by ischemia of the left renal artery and vein for 45 min followed by reperfusion, 2 weeks after the removal of right kidney. The efficacy of SMTP-7 was determined by measuring the renal function using urine and serum samples and morphological assessment. For deciphering the mechanism of action of SMTP-7, inflammatory cytokines and oxidative stress in kidney were detected. SMTP-7 (0.01, 0.1, 1, 10 mg/kg) dose-dependently improved the renal function. In addition, it improved the damage to renal tubules and exhibited anti-inflammatory and antioxidant activities in the kidney of AKI mice. These results indicate the potential of SMTP-7 as a medicinal compound for the treatment of AKI.

Clinically translatable gold nanozymes with broad spectrum antioxidant and anti-inflammatory activity for alleviating acute kidney injury

Rationale: Acute kidney injury (AKI) is associated with aberrant generation of oxidative species and inflammation, leading to high mortality of in-hospitalized patients. Although N-acetylcysteine (NAC) showed positive effects in alleviating contrast-induced AKI, the clinical applications are strongly restrained due to the low bioavailability, low renal accumulation, short renal retention time, and high dosage-induced toxicity. Methods: We addressed the clinical dilemma of NAC by developing ultrasmall gold nanoclusters (1-2 nm) capped with NAC (denoted as Au NCs-NAC) as a nanozyme-based antioxidant defense system for AKI alleviation. Rhabdomyolysis-induced AKI mice model was developed, and the same dose of free NAC (as a control) and NAC onto Au NCs (Au NCs-NAC) was used for in vivo investigation of AKI restoration. Results: The as-developed gold nanozyme exhibited high bioavailability and good physicochemical stability as compared to NAC. Meanwhile, Au NCs-NAC showed broad-spectrum antioxidant activity of Au NCs-NAC, offering in vitro renoprotective effects, as well as macrophages by relieving inflammation under hydrogen peroxide or lipopolysaccharide stimulation. Notably, owing to the smaller size than kidney threshold (5.5 nm), Au NCs-NAC displayed preferential renal enrichment (< 2 h) and longer retention (> 24 h) in AKI mice as revealed by fluorescence imaging, thereby largely enhancing the restoration of renal function in AKI mice than free NAC by protecting the kidneys from oxidative injury and inflammation without systemic toxicity, as demonstrated by tissues staining, inflammatory cytokines and biomarkers detection, and mice survival rate. Conclusion: Owing to the synergistic anti-inflammatory/antioxidative effects, and enhanced bioavailability and renal accumulation/retention, Au NCs-NAC displayed far superior therapeutic performance than NAC alone. This work will facilitate the development of high-performance antioxidative nanoplatforms, as well as overcome the clinical limitations of small molecular drugs for AKI treatment and other inflammatory diseases.

Redox-Mediated Artificial Non-Enzymatic Antioxidant MXene Nanoplatforms for Acute Kidney Injury Alleviation

Acute kidney injury (AKI), as a common oxidative stress-related renal disease, causes high mortality in clinics annually, and many other clinical diseases, including the pandemic COVID-19, have a high potential to cause AKI, yet only rehydration, renal dialysis, and other supportive therapies are available for AKI in the clinics. Nanotechnology-mediated antioxidant therapy represents a promising therapeutic strategy for AKI treatment. However, current enzyme-mimicking nanoantioxidants show poor biocompatibility and biodegradability, as well as non-specific ROS level regulation, further potentially causing deleterious adverse effects. Herein, the authors report a novel non-enzymatic antioxidant strategy based on ultrathin Ti3 C2 -PVP nanosheets (TPNS) with excellent biocompatibility and great chemical reactivity toward multiple ROS for AKI treatment. These TPNS nanosheets exhibit enzyme/ROS-triggered biodegradability and broad-spectrum ROS scavenging ability through the readily occurring redox reaction between Ti3 C2 and various ROS, as verified by theoretical calculations. Furthermore, both in vivo and in vitro experiments demonstrate that TPNS can serve as efficient antioxidant platforms to scavenge the overexpressed ROS and subsequently suppress oxidative stress-induced inflammatory response through inhibition of NF-κB signal pathway for AKI treatment. This study highlights a new type of therapeutic agent, that is, the redox-mediated non-enzymatic antioxidant MXene nanoplatforms in treatment of AKI and other ROS-associated diseases.

The effects of edaravone, a free-radical scavenger in lung injury induced by valproic acid demonstrated via different biochemical parameters

In this study, we aimed to evaluate whether edaravone (EDA) has a protective role against valproic acid (VPA)-induced lung damage via its antioxidative activity. Male Sprague-Dawley rats were split into four groups. Control (n = 8) rats; rats given EDA (30 mg kg^-1  day^-1 ; n = 10); rats given only (VPA, 500 mg kg^-1  day^-1 ; n = 10); rats given VPA + EDA (in the same dose and time) for 7 days. EDA and VPA were applied intraperitoneally. After 8 days, lung tissues were immediately taken from the rats. In lung homogenates, reduced glutathione, total antioxidant status levels, and superoxide dismutase, glutathione peroxidase, sodium/potassium ATPase, paraoxonase1, and carbonic anhydrase activities significantly abated, whereas catalase, glutathione reductase, glutathione-S-transferase activities insignificantly decreased in the VPA-treated group. In contrast, lipid peroxidation, reactive oxygen species, and total oxidant status levels, glycoprotein and protein carbonyl contents, nitric oxide, hydroxyproline levels, and xanthine oxidase, lactate dehydrogenase, arginase, and prolidase activities significantly increased in the VPA-given group. Administration of EDA caused the reverse effects. As a consequence, EDA prevented oxidative stress-mediated lung injury via its robust antioxidant effects.

Multi-enzyme mimetic ultrasmall iridium nanozymes as reactive oxygen/nitrogen species scavengers for acute kidney injury management

Acute kidney injury (AKI) is a kind of kidney disease with a high mortality rate, and is predominantly associated with abundant endogenous reactive oxygen/nitrogen species (RONS). However, there are no universal clinical treatment options currently. Development of antioxidants with high kidney enrichment is highly desired to prevent AKI. As a promising new artificial enzyme, nanozymes have attracted extensive attention over the past decade because of their commendable advantages over natural and traditional artificial enzymes. In this study, we reported ultrasmall polyvinylpyrrolidone-coated iridium nanoparticles (denoted as Ir NPs-PVP, 1.5 nm) as multi-enzyme mimetic to scavenge a variety of RONS, offering an efficient RONS-induced cellular protection. Meanwhile, computed tomography and inductively coupled plasma mass spectrometry demonstrated preferential renal uptake of Ir NPs-PVP following intravenous administration, leading to alleviate clinical symptoms in mice subjected to rhabdomyolysis- or cis-platinum-induced AKI. Impressively, ultrasmall Ir NPs-PVP exhibit relatively low systemic side effects in vivo due to rapid renal clearance via urine. Our work presents the clinically translatable potential of ultrasmall nanozymes for AKI management.

Protective effect of edaravone against radiation-induced ovarian injury: a histopathological and immunohistochemical evaluation in an experimental rat model

PURPOSE

We aimed to evaluate the protective effect of edaravone on radiation-induced ovarian damage in an experimental rat model.

METHODS

Thirty-two Wistar albino female rats were randomly divided into four groups. Group 1: control, no treatment, and radiation was applied throughout the study; Group 2: sham, only radiation was applied; Group 3: 45 mg/kg edaravone and radiation were applied; Group 4: 450 mg/kg edaravone and radiation were applied. Edaravone was administered intraperitoneally 30 min before radiotherapy (5 Gy). Two days after radiation exposure, the rats were sacrificed and the ovaries were removed. Histologic changes under light microscopy and immunoreactivity for anti-caspase-3 were noted and compared between the four groups.

RESULTS

There was a statistically significant difference in follicle counts, vascular congestion, edema, cytoplasmic vacuolization, hemorrhage, and interstitial cell degeneration between the groups. Radiation causes deterioration in most histopathological parameters. Administration of edaravone at different doses seems to reverse these alterations and alleviate the injury. Antioxidant defense mechanisms appear to be enhanced by edaravone as shown by histopathologically and decreased apoptosis by reducing the expression of anti-caspase-3 activity as demonstrated immunohistochemically.

CONCLUSION

This is the first study evaluating the protective effects of edaravone on radiation-induced ovarian damage. Edaravone decreased the follicular apoptosis and attenuates the radiation-induced ovarian damage in rats.

Trimebutine attenuates high mobility group box 1-receptor for advanced glycation end-products inflammatory signaling pathways

We previously identified papaverine as an inhibitor of receptor for advanced glycation end-products (RAGE) and showed its suppressive effect on high mobility group box 1 (HMGB1)-mediated responses to inflammation. Here, we found trimebutine to be a 3D pharmacophore mimetics of papaverine. Trimebutine was revealed to have more potent suppressive effects on HMGB1-induced production of pro-inflammatory cytokines, such as interleukin-6 and tumor necrosis factor-α in macrophage-like RAW264.7 cells and mouse bone marrow primarily differentiated macrophages than did papaverine. However, the inhibitory effect of trimebutine on the interaction of HMGB1 and RAGE was weaker than that of papaverine. Importantly, mechanism-of-action analyses revealed that trimebutine strongly inhibited the activation of RAGE downstream inflammatory signaling pathways, especially the activation of extracellular signal-regulated kinase 1 and 2 (ERK1/2), which are mediator/effector kinases recruited to the intracellular domain of RAGE. Consequently, the activation of Jun amino terminal kinase, which is an important effector kinase for the up-regulation of pro-inflammatory cytokines, was inhibited. Taken together, these results suggest that trimebutine may exert its suppressive effect on the HMGB1-RAGE inflammatory signal pathways by strongly blocking the recruitment of ERK1/2 to the intracellular tail domain of RAGE in addition to its weak inhibition of the extracellular interaction of HMGB1 with RAGE. Thus, trimebutine may provide a unique scaffold for the development of novel dual inhibitors of RAGE for inflammatory diseases.

Edaravone Protects against Pancreatic and Intestinal Injury after Acute Pancreatitis via Nuclear Factor-κB Signaling in Mice

Acute pancreatitis (AP) is one kind of acute surgical abdominal disease in the world. It causes intestinal damage with subsequent bacterial migration, endotoxemia and secondary pancreatic infections. In this investigation, we determined that edaravone (EDA) reduces pancreatic and intestinal injury after AP in mice. This was demonstrated by a reduction in histological score, apoptosis, interleukin (IL)-6, IL-1β and tumor necrosis factor (TNF)-α, along with obstructing activation of Toll-like receptor 4 (TLR4) and nuclear factor-κB (NFκB). Our study results suggested that EDA exerts its protective effects against pancreatic and intestinal injury after AP via regulation of the TLR4/NFκB pathway. Our findings provide the basis for EDA to treat AP-induced pancreatic and intestinal injury, even might develop as a potential therapy for other inflammatory diseases.

The Protective Effects of Perindopril Against Acute Kidney Damage Caused by Septic Shock

Acute kidney injury (AKI) resulting from septic shock caused by sepsis is an important health problem encountered at rates of 55-73%. Increasing oxidative stress and inflammation following sepsis is a widely observed condition with rising mortality rates. The purpose of this study was to determine whether perindopril (PER) can prevent sepsis-associated AKI with its antioxidant, anti-inflammatory, and anti-apoptotic effects. The control group received an oral saline solution only for 4 days. Cecal ligation and puncture (CLP)-induced sepsis only was applied to the CLP group, while the CLP + PER (2 mg/kg) received CLP-induced sepsis together with 2 mg/kg PER via the oral route for 4 days before induction of sepsis. Finally, all rats were euthanized by anesthesia and sacrificed. TBARS, total SH levels and NF-κβ, TNF-α, and Caspase-3 expression were then calculated for statistical analysis. TBARS, total SH, NF-kβ/p65, TNF-a, and Caspase-3 levels increased in the CLP group. In contrast, oral administration of PER (2 mg/kg) to septic rats reduced TBARS levels and NF-kβ/p65, TNF-α, and Caspase-3 immunopositivity at biochemical analysis. PER treatment appears to be a promising method for preventing sepsis-induced acute kidney injury through its antioxidant anti-inflammation and anti-apoptotic activities.

Protection of procyanidin B2 on mitochondrial dynamics in sepsis associated acute kidney injury via promoting Nrf2 nuclear translocation

In septic acute kidney injury (SAKI), the positive feedback between damaged mitochondria and accumulation of reactive oxygen species results in cell and tissue damage through multiple mechanisms. Removing the damaged mitochondria or neutralizing the reactive oxygen species has been considered beneficial to alleviating cell damage. The antioxidant Procyanidin B2 has been reported to inhibits reactive oxygen species and thereby reduces cell injury. However, it is unclear whether this effect is associated with clearance of damaged mitochondria. Here, we evaluated the efficacy of procyanidin B2 on SAKI, and focused on its effects on mitochondrial dynamics and removing damaged mitochondria via mitophagy. The results showed that the renal function, renal tubular cell vacuolization and oxidative stress were decreased in SAKI mice treated with procyanidin B2, moreover, skewed mitochondrial fusion/fission, mitochondrial mediated apoptosis and impaired mitophagy were improved in SAKI mice treated with procyanidin B2. In mechanism, the improvement of procyanidin B2 on mitochondrial dynamics were associated with increased nuclear translocation of the transcription factor, Nrf2. In summary, our findings highlighted that the protective efficacy of procyanidin B2 in reducing cellular damage in SAKI, and mechanisms improving mitochondrial dynamics and quality control at least in part by promoting Nrf2 translocation into the nucleus.

Neuronal Mitochondria Modulation of LPS-Induced Neuroinflammation

Neuronal mitochondria dysfunction and neuroinflammation are two prominent pathological features increasingly realized as important pathogenic mechanisms for neurodegenerative diseases. However, little attempt has been taken to investigate the likely interactions between them. Mitofusin2 (Mfn2) is a mitochondrial outer membrane protein regulating mitochondrial fusion, a dynamic process essential for mitochondrial function. To explore the significance of neuronal mitochondria in the regulation of neuroinflammation, male and female transgenic mice with forced overexpression of Mfn2 specifically in neurons were intraperitoneally injected with lipopolysaccharide (LPS), a widely used approach to model neurodegeneration-associated neuroinflammation. Remarkably, LPS-induced lethality was almost completely abrogated in neuronal Mfn2 overexpression mice. Compared with nontransgenic wild-type mice, mice with neuronal Mfn2 overexpression also exhibited alleviated bodyweight loss, behavioral sickness, and myocardial dysfunction. LPS-induced release of IL-1β but not TNF-α was further found greatly inhibited in the CNS of mice with neuronal Mfn2 overexpression, whereas peripheral inflammatory responses in the blood, heart, lung, and spleen remained unchanged. At the cellular and molecular levels, neuronal Mfn2 suppressed the activation of microglia, prevented LPS-induced mitochondrial fragmentation in neurons, and importantly, upregulated the expression of CX3CL1, a unique chemokine constitutively produced by neurons to suppress microglial activation. Together, these results reveal an unrecognized possible role of neuronal mitochondria in the regulation of microglial activation, and propose neuronal Mfn2 as a likely mechanistic linker between neuronal mitochondria dysfunction and neuroinflammation in neurodegeneration.SIGNIFICANCE STATEMENT Our study suggests that Mfn2 in neurons contributes to the regulation of neuroinflammation. Based on the remarkable suppression of LPS-induced neuroinflammation and neurodegeneration-associated mitochondrial dysfunction and dynamic abnormalities by neuronal Mfn2, this study centered on Mfn2-mediated neuroinflammation reveals novel molecular mechanisms that are involved in both mitochondrial dysfunction and neuroinflammation in neurodegenerative diseases. The pharmacological targeting of Mfn2 may present a novel treatment for neuroinflammation-associated diseases.

A role of AMPK and connexin 43 in the suppression of CoCl2-induced apoptosis of spiral modiolar artery smooth muscle cells by adiponectin

AIMS

Adiponectin (APN) is a protein hormone secreted mainly by adipose tissue that exhibits biological functions such as anti-inflammatory, anti-atherosclerotic, anti-apoptotic, hearing-protective and microcirculation-regulating functions. In this study, we explored whether APN could attenuate damage caused by CoCl₂-induced hypoxic conditions in smooth muscle cells (SMCs) of the spiral modiolar artery (SMA).

MAIN METHODS

We first cultured and identified primary SMCs of the SMA. Afterward, the SMCs were pre-treated with APN and then stimulated with CoCl₂.

KEY FINDINGS

Compared with the control group, the group treated with CoCl₂ for 24 h exhibited significantly decreased cell viability, significantly increased apoptosis rates and Malondialdehyde (MDA) levels, and decreased Superoxide Dismutase (SOD) activity. In addition, the expression levels of Bax and cleaved caspase-3 were upregulated, while those of Bcl2 were downregulated evidently. Compared with the CoCl₂ group, the group pre-treated with APN before receiving CoCl₂ treatment had increased cell viability and SOD activity but decreased MDA levels and apoptosis rates. The expression levels of Bcl2, p-AMPKα and Cx43 were evidently increased, while those of Bax and cleaved caspase-3 were decreased, in the group pre-treated with APN compared to the CoCl₂ group. The protective effect of APN was blocked by the AMPK inhibitor Compound C and the Cx43 inhibitor Gap19.

SIGNIFICANCE

Our study demonstrated that APN protected SMCs against CoCl₂-induced hypoxic injury via the AMPK signalling pathway and regulated the expression of Cx43 in cells. Therefore, APN might be a promising treatment for diseases related to circulation disturbances of the inner ear.

Effect of edaravone against cisplatin-induced chronic renal injury

Cisplatin has been widely used as an anticancer agent for a wide range of tumors, but it had nephrotoxicity that was mainly caused by oxidative stress. Edaravone, a free radical scavenger, has reportedly been validated to have a protective effect against renal injury induced by reactive oxygen species. However, most of these reports are against AKI, and few studies have examined the effect of chronic renal injury. In this study, we investigate the effect of edaravone on cisplatin nephropathy in the chronic phase. Twenty-five male Wistar rats were divided into five groups: control, cisplatin, cisplatin + edaravone 1 mg kg^-1, cisplatin + edaravone 10 mg kg^-1, and cisplatin + edaravone 100 mg kg^-1. Edaravone was administrated intraperitoneally every other day for 5 weeks, starting 1 week before cisplatin administration (6 mg kg^-1, i.p.). As a result, proximal tubule injury, interstitial fibrosis, and mononuclear cell infiltration were ameliorated histologically in the group of rats treated with high edaravone dose. In the cisplatin group, the number of α-SMA-, CD68-, and CD3-positive cells increased markedly compared with the Control group, but these numbers were significantly decreased by higher doses of co-administered edaravone. While there was no clear mRNA expression variation in antioxidant enzymes, the apoptosis-promoting factors, caspase8, were markedly reduced in the high-dose edaravone co-administration group compared with the cisplatin group. In conclusion, our results suggested that cisplatin-induced renal injury in the chronic phase was ameliorated by edaravone.

Molybdenum-based nanoclusters act as antioxidants and ameliorate acute kidney injury in mice

Acute kidney injury (AKI) is a common reactive oxygen species (ROS)-related renal disease that causes numerous deaths annually, yet only supportive treatment is currently available in the clinics. Development of antioxidants with high accumulation rates in kidneys is highly desired to help prevent AKI. Here we report molybdenum-based polyoxometalate (POM) nanoclusters with preferential renal uptake as novel nano-antioxidants for kidney protection. These POM nanoclusters, with a readily variable valence state of molybdenum ions, possess the capability to scavenge detrimental ROS. Our results demonstrate that POM nanoclusters can efficiently alleviate clinical symptoms in mice subjected to AKI, as verified by dynamic PET imaging with ⁶⁸Ga-EDTA, serum tests, kidney tissue staining, and biomarkers detection in the kidneys. The protective effect of POM nanoclusters against AKI in living animals suggests exploring their use for the treatment of AKI patients, as well as patients with other ROS-related diseases.

There are currently no effective therapies available for acute kidney injury (AKI). Here the authors generate molybdenum-based polyoxometalate nanoclusters and show that these have preferential renal uptake and can ameliorate AKI pathology in mice by scavenging reactive oxygen species.

Protective effect of sesamin in lipopolysaccharide-induced mouse model of acute kidney injury via attenuation of oxidative stress, inflammation, and apoptosis

CONTEXT

Acute kidney injury (AKI) is considered a major public health concern in today's world. Sepsis-induced AKI is large as a result of exposure to lipopolysaccharide (LPS) that is the major outer membrane component of Gram-negative bacteria. Sesamin is the main lignan of sesame seeds with multiple protective effects.

OBJECTIVE

In this research, we tried to demonstrate the protective effect of sesamin pretreatment in LPS-induced mouse model of AKI.

METHODS

LPS was injected at a single dose of 10 mg/kg (i.p.) and sesamin was given p.o. at doses of 25, 50, or 100 mg/kg, one hour prior to LPS.

RESULTS

Treatment of LPS-challenged mice with sesamin reduced serum level of creatinine and blood urea nitrogen (BUN) and returned back renal oxidative stress-related parameters including glutathione (GSH), malondialdehyde (MDA), and activity of catalase and superoxide dismutase (SOD). Moreover, sesamin alleviated inappropriate changes of renal nuclear factor-kappaB (NF-κB), toll-like receptor 4 (TLR4), cyclooxygenase-2 (COX2), tumor necrosis factor α (TNFα), interleukin-6, DNA fragmentation (an apoptotic index), and nuclear factor (erythroid-derived 2)-like 2 (Nrf2). In addition, sesamin diminished magnitude of kidney tissue damage due to LPS.

CONCLUSION

In summary, sesamin could dose-dependently abrogate LPS-induced AKI via attenuation of renal oxidative stress, inflammation, and apoptosis.

Rutin, a quercetin glycoside, alleviates acute endotoxemic kidney injury in C57BL/6 mice via suppression of inflammation and up-regulation of antioxidants and SIRT1

Acute kidney injury (AKI) is a common complication following severe sepsis, its incidence is increasing, and it is associated with a high rate of morbidity and mortality. Rutin is a glycoside of the bioflavonoid quercetin with various protective effects due to its antioxidant and anti-inflammatory potential. In this research, we tried to assess the protective effect of rutin administration in a model of AKI in C57BL/6 mice. For induction of AKI, lipopolysaccharide (LPS) was injected once (10 mg/kg, i.p.) and rutin was p.o. given at doses of 50 or 200 mg/kg. Treatment of LPS-challenged group with rutin lowered serum level of creatinine and blood urea nitrogen (BUN), restored to some extent renal oxidative stress-related indices such as malondialdehyde (MDA), glutathione (GSH), and activity of superoxide dismutase (SOD) and catalase. In addition, rutin brought back renal nuclear factor-kappaB (NF-κB), toll-like receptor 4 (TLR4), cyclooxygenase-2 (COX2), sirtuin 1 (SIRT1), tumor necrosis factor α (TNFα), interleukin-6, and caspase 3 activity to their control levels. Moreover, protective effect of rutin was in accordance to a dose-dependent manner. Collectively, rutin is capable to mitigate LPS-induced AKI via appropriate modulation of renal oxidative stress, inflammation, and apoptosis.

Kidney disease models: tools to identify mechanisms and potential therapeutic targets

Acute kidney injury (AKI) and chronic kidney disease (CKD) are worldwide public health problems affecting millions of people and have rapidly increased in prevalence in recent years. Due to the multiple causes of renal failure, many animal models have been developed to advance our understanding of human nephropathy. Among these experimental models, rodents have been extensively used to enable mechanistic understanding of kidney disease induction and progression, as well as to identify potential targets for therapy. In this review, we discuss AKI models induced by surgical operation and drugs or toxins, as well as a variety of CKD models (mainly genetically modified mouse models). Results from recent and ongoing clinical trials and conceptual advances derived from animal models are also explored.

Edaravone Improves Septic Cardiac Function by Inducing an HIF-1α/HO-1 Pathway

Septic myocardial dysfunction remains prevalent and raises mortality rate in patients with sepsis. During sepsis, tissues undergo tremendous oxidative stress which contributes critically to organ dysfunction. Edaravone, a potent radical scavenger, has been proved beneficial in ischemic injuries involving hypoxia-inducible factor- (HIF-) 1, a key regulator of a prominent antioxidative protein heme oxygenase- (HO-) 1. However, its effect in septic myocardial dysfunction remains unclarified. We hypothesized that edaravone may prevent septic myocardial dysfunction by inducing the HIF-1/HO-1 pathway. Rats were subjected to cecal ligation and puncture (CLP) with or without edaravone infusion at three doses (50, 100, or 200 mg/kg, resp.) before CLP and intraperitoneal injection of the HIF-1α antagonist, ME (15 mg/kg), after CLP. After CLP, rats had cardiac dysfunction, which was associated with deformed myocardium, augmented lipid peroxidation, and increased myocardial apoptosis and inflammation, along with decreased activities of catalase, HIF-1α, and HO-1 in the myocardium. Edaravone pretreatment dose-dependently reversed the changes, of which high dose most effectively improved cardiac function and survival rate of septic rats. However, inhibition of HIF-1α by ME demolished the beneficial effects of edaravone at high dose, reducing the survival rate of the septic rats without treatments. Taken together, edaravone, by inducing the HIF-1α/HO-1 pathway, suppressed oxidative stress and protected the heart against septic myocardial injury and dysfunction.

The antioxidant edaravone prevents cardiac dysfunction by suppressing oxidative stress in type 1 diabetic rats and in high-glucose-induced injured H9c2 cardiomyoblasts

Edaravone, a radical scavenger, has been recognized as a potential protective agent for cardiovascular diseases. However, little is known about the effect of edaravone in cardiac complications associated with diabetes. Here, we have demonstrated that edaravone prevents cardiac dysfunction and apoptosis in the streptozotocin-induced type 1 diabetic rat heart. Mechanistic studies revealed that edaravone treatment improved cardiac function and restored superoxide dismutase levels. In addition, treatment of diabetic animals by edaravone increased protein expressions of sirtuin-1 (SIRT-1), peroxisome proliferator activated receptor γ coactivator α (PGC-1α), nuclear factor like-2 (NRF-2), and B cell lymphoma 2 (Bcl-2), and reduced protein expressions of Bax and Caspase-3 compared to the control group. High glucose incubation resulted in the production of reactive oxygen species (ROS) and cell death. Treatment of high-glucose-incubated H9c2 cells by edaravone reduced ROS production and cell death. In addition, the treatment of high-glucose-incubated H9c2 cells by edaravone increased the activity of antioxidative stress by increasing SIRT-1, PGC-1α, and NRF-2, and this treatment also reduced apoptosis by increasing Bcl-2 expression and reducing Bax and Caspase-3 expressions. Knockdown SIRT-1 with small interferer RNA abolished the effects of edaravone. Overall, our data demonstrated that edaravone may be an effective agent against the development of diabetic cardiomyopathy.

Tenuigenin exhibits protective effects against LPS-induced acute kidney injury via inhibiting TLR4/NF-κB signaling pathway

Tenuigenin (TNG) has been reported to have various pharmacological activities, such as anti-oxidative and anti-inflammatory activities. However, the protective effects of TNG on lipopolysaccharides (LPS)-induced acute kidney injury (AKI) are still not clear. The aim of this study was to investigate the protective effects and mechanism of TGN on LPS-induced AKI in mice. The kidney histological change, levels of blood urea nitrogen (BUN), and creatinine were measured to assess the protective effects of TNG on LPS-induced AKI. The levels of TNF-α, IL-1β, and IL-6 in serum and kidney tissues were detected by ELISA. The extent of nuclear factor kappa-B (NF-κB) p65 and the expression of Toll-like receptor-4 (TLR4) were detected by western blot analysis. The results showed that TNG markedly attenuated the histological alterations, BUN and creatinine levels in kidney. TNG also suppressed LPS-induced TNF-α, IL-1β, and IL-6 production. Furthermore, the expression of TLR4 and NF-κB activation induced by LPS were markedly inhibited by TNG. In conclusion, this study demonstrated that TNG protected against LPS-induced AKI by inhibiting TLR4/NF-κB signaling pathway.

Nephroprotection of punicalagin in rat model of endotoxemic acute kidney injury

The potential nephroprotection of punicalagin (PNG) against lipopolysaccharide (LPS)-induced acute kidney injury in rats was investigated. Rats received a single i.v. dose of LPS (5 mg/kg), and treated with PNG (50 mg/kg, i.p.), 1 h before, and 1 h following LPS administration. LPS caused significant increases of serum creatinine and neutrophil gelatinase-associated lipocalin. LPS also resulted in significant increases in interleukin-18, tumor necrosis factor-α, interleukin-6, malondialdehyde, nitric oxide, Bax/Bcl-2 ratio and myeloperoxidase, inducible nitric oxide synthase, caspases 3, 8 and 9 activities, and a significant decrease in total antioxidant capacity in kidney tissues. PNG significantly ameliorated the alterations in the measured parameters. Additionally, PNG attenuated the histopathological injury and reduced kidney injury molecule-1 expression in kidneys of rats that received LPS. It was concluded that PNG ameliorated endotoxemic acute kidney injury in rats by counteracting inflammation, oxidative/nitrative stress and apoptosis.

Edaravone abrogates LPS-induced behavioral anomalies, neuroinflammation and PARP-1

Poly(ADP-ribose) polymerase-1 (PARP-1) is a DNA nick-sensor enzyme that functions at the center of cellular stress response and affects the immune system at several key points, and thus modulates inflammatory diseases. Our previous study demonstrated that lipopolysaccharide (LPS)-induced depressive-like behavior in mice can be ameliorated by 3-aminobenzamide, which is a PARP-1 inhibitor. In the present study we've examined the effect of a free radical scavenger, edaravone pretreatment against LPS-induced anxiety and depressive-like behavior as well as various hippocampal biochemical parameters including PARP-1. Male Swiss albino mice were treated with edaravone (3 & 10mg/kgi.p.) once daily for 14days. On the 14th day 30min after edaravone treatment mice were challenged with LPS (1mg/kgi.p.). After 3h and 24h of LPS administration we've tested mice for anxiety and depressive-like behaviors respectively. Western blotting analysis of PARP-1 in hippocampus was carried out after 12h of LPS administration. Moreover, after 24h of LPS administration serum corticosterone, hippocampal BDNF, oxido-nitrosative stress and pro-inflammatory cytokines were estimated by ELISA. Results showed that pretreatment of edaravone (10mg/kg) ameliorates LPS-induced anxiety and depressive-like behavior. Western blotting analysis showed that LPS-induced anomalous expression of PARP-1 significantly reverses by the pretreatment of edaravone (10mg/kg). Biochemical analyses revealed that LPS significantly diminishes BDNF, increases pro-inflammatory cytokines and oxido-nitrosative stress in the hippocampus. However, pretreatment with edaravone (10mg/kg) prominently reversed all these biochemical alterations. Our study emphasized that edaravone pretreatment prevents LPS-induced anxiety and depressive-like behavior, mainly by impeding the inflammation, oxido-nitrosative stress and PARP-1 overexpression.