The polarization of M2 macrophages can be adjusted to alleviate renal injury by methylprednisolone in sepsis-AKI

Acute kidney injury in sepsis patients has an extreme mortality rate in clinical. It obviously seems that immune cells, for example, macrophages are involved with this process. Macrophages, as highly important immune cells, play a significant role in the development of human kidney diseases. But the specific role of macrophages in this process is still unclear. Under different timeline points, we surprisingly found that macrophages had the most dynamic changes in acute kidney injury immune cells. Based on macrophages' functions, they are primarily classified into M1 macrophages (pro-inflammatory) and M2 macrophages (anti-inflammatory). The polarization of M2 macrophages is closely associated with the seriousness of sepsis-induced kidney injury, but how to modulate their polarization to alleviate sepsis-associated renal damage remains unknown. We discovered that the polarization of M2 macrophages after methylprednisolone injection can significantly alleviate acute kidney injury by reducing secreted cytokine. This study suggests that the proportion of macrophage subtypes can be regulated by methylprednisolone to alleviate acute kidney injury in sepsis to provide a new sight for a clinical to provide a promising strategy for renal injury caused.

Identifying Serum Metabolites and Gut Bacterial Species Associated with Nephrotoxicity Caused by Arsenic and Fluoride Exposure

Co-contamination of arsenic (As) and fluoride (F) is widely distributed in groundwater, which are known risk factors for the nephrotoxicity. Emerging evidence has linked environmentally associated nephrotoxicity with the disturbance of gut microbiota and blood metabolites. In this study, we generated gut microbiota and blood metabolomic profile and identified multiple serum metabolites and gut bacteria species, which were associated with kidney injury on rat model exposed to As and F alone or combined. Combined As and F exposure significantly increased creatinine level. Abnormal autophagosomes and lysosome were observed, and the autophagic genes were enhanced in kidney tissue after single and combined As and F exposure. The metabolome data showed that single and combined As and F exposure remarkably altered the serum metabolites associated with the proximal tubule reabsorption function pathway, with glutamine and alpha-ketoglutarate level decreased in all exposed group. Furthermore, phosphatidylethanolamine (PE), the key contributor of autophagosomes, was decreased significantly in As and F + As exposed groups during the screen of autophagy-animal pathway. Multiple altered gut bacterial microbiota at phylum and species levels post As and F exposure were associated with targeted kidney injury, including p_Bacteroidetes, s_Chromohalobacter_unclassified, s_Halomonas_unclassified, s_Ignatzschineria_unclassified, s_Bacillus_subtilis, and s_Brevundimonas_sp._NA6. Meanwhile, our analysis indicated that As and F co-exposure possessed an interactive influence on gut microbiota. In conclusion, single or combined As and F exposure leads to the disruption of serum metabolic and gut microbiota profiles. Multiple metabolites and bacterial species are identified and associated with nephrotoxicity, which have potential to be developed as biomarkers of As and/or F-induced kidney damage.

Cytosine-phosphate-guanine oligodeoxynucleotides alleviate radiation-induced kidney injury in cervical cancer by inhibiting DNA damage and oxidative stress through blockade of PARP1/XRCC1 axis

BACKGROUND

Radiotherapy can cause kidney injury in patients with cervical cancer. This study aims to investigate the possible molecular mechanisms by which CpG-ODNs (Cytosine phosphate guanine-oligodeoxynucleotides) regulate the PARP1 (poly (ADP-ribose) polymerase 1)/XRCC1 (X-ray repair cross-complementing 1) signaling axis and its impact on radiation kidney injury (RKI) in cervical cancer radiotherapy.

METHODS

The GSE90627 dataset related to cervical cancer RKI was obtained from the Gene Expression Omnibus (GEO) database. Bioinformatics databases and R software packages were used to analyze the target genes regulated by CpG-ODNs. A mouse model of RKI was established by subjecting C57BL/6JNifdc mice to X-ray irradiation. Serum blood urea nitrogen (BUN) and creatinine levels were measured using an automated biochemical analyzer. Renal tissue morphology was observed through HE staining, while TUNEL staining was performed to detect apoptosis in renal tubular cells. ELISA was conducted to measure levels of oxidative stress-related factors in mouse serum and cell supernatant. An in vitro cell model of RKI was established using X-ray irradiation on HK-2 cells for mechanism validation. RT-qPCR was performed to determine the relative expression of PARP1 mRNA. Cell proliferation activity was assessed using the CCK-8 assay, and Caspase 3 activity was measured in HK-2 cells. Immunofluorescence was used to determine γH2AX expression.

RESULTS

Bioinformatics analysis revealed that the downstream targets regulated by CpG-ODNs in cervical cancer RKI were primarily PARP1 and XRCC1. CpG-ODNs may alleviate RKI by inhibiting DNA damage and oxidative stress levels. This resulted in significantly decreased levels of BUN and creatinine in RKI mice, as well as reduced renal tubular and glomerular damage, lower apoptosis rate, decreased DNA damage index (8-OHdG), and increased levels of antioxidant factors associated with oxidative stress (SOD, CAT, GSH, GPx). Among the CpG-ODNs, CpG-ODN2006 had a more pronounced effect. CpG-ODNs mediated the inhibition of PARP1, thereby suppressing DNA damage and oxidative stress response in vitro in HK-2 cells. Additionally, PARP1 promoted the formation of the PARP1 and XRCC1 complex by recruiting XRCC1, which in turn facilitated DNA damage and oxidative stress response in renal tubular cells. Overexpression of either PARP1 or XRCC1 reversed the inhibitory effects of CpG-ODN2006 on DNA damage and oxidative stress in the HK-2 cell model and RKI mouse model.

CONCLUSION

CpG-ODNs may mitigate cervical cancer RKI by blocking the activation of the PARP1/XRCC1 signaling axis, inhibiting DNA damage and oxidative stress response in renal tubule epithelial cells.

Occurrence and influencing factors of cyclosporine A on the kidney injury following allogeneic hematopoietic stem cell transplantation: A systematic review and meta-analysis

OBJECTIVE

Whether cyclosporine A (CsA) is a risk factor of kidney injury after allogeneic hematopoietic stem cell transplantation (allo-HSCT) has not been determined. We aim to comprehensively review the correlation and influencing factors between CsA and kidney injury in patients following allo-HSCT.

METHODS

We searched PubMed, Embase (Ovid), Cochrane Central Register of Controlled Trials (CENTRAL), CNKI, VIP, Wanfang and CBM Database from inception to March 2022. Two researchers independently conducted literature screening, data extraction and quality assessment. Qualitative and quantitative methods were combined to analyze the data.

RESULTS

We included a total of 30 studies. Meta-analyses of total incidence of kidney injury related to CsA was 37.0% [95% CI (25.4%, 48.6%); n = 15]. The proportion of CsA-related acute kidney injury to total acute kidney injury following allo-HSCT was 59.7% [95% CI (49.1%, 70.3%); n = 9]. One study found that AKI had a significant association with CsA in multivariate analysis [RR = 6.173; 95% CI (4.032, 9.434)]. With respect to cyclosporine combination and nephrotoxicity, 6/9 studies demonstrated that the concomitant medications for CsA (especially aminoglycoside antibiotics and amphotericin B) had negative effect on kidney functions related to CsA in allo-HSCT patients. No consensus was reached for "dose of CsA", "duration of CsA use", "comorbidities" and "CsA levels" across studies.

CONCLUSIONS

CsA may be a risk factor for kidney injury in patients following allo-HSCT, especially the concomitant use of CsA and nephrotoxic medications.

Baicalein ameliorates polymyxin B-induced acute renal injury by inhibiting ferroptosis via regulation of SIRT1/p53 acetylation

The polypeptide antibiotic Polymyxin B (PMB) can cause acute kidney injury (AKI), we found that ferroptosis is one of the main mechanisms of renal injury caused by PMB. It was reported that baicalein can inhibit ferroptosis. Therefore, in this study we examined whether baicalein could attenuate PMB-induced renal injury by inhibiting ferroptosis. We confirmed that baicalein could reduce PMB-induced renal injury in vivo and in vitro studies. In the in vitro study, baicalein significantly increased the survival rate of human HK2 tubular epithelial cells. The results of HE staining and electron microscopy in mice also showed that baicalein reduced PMB-induced renal injury, and significantly decreased the levels of BUN and Scr. By detecting ferroptosis-related indicators, we found that pre-incubation of baicalein in HK2 cells down-regulated Fe2+ level, lipid peroxidation, MDA and HO-1 which had been increased by PMB. Furthermore, baicalein up-regulated the levels of SCL7A11, GPX4 and GSH that were decreased by PMB. Moreover, intraperitoneal injection of baicalein in the animal model down-regulated kidney iron level, PTGS2 and 4HNE, and increased the GSH level, which suggested that baicalein could inhibit PMB-induced ferroptosis. Finally, by detecting changes in levels of p53 and p53 K382 acetylation, baicalein was observed to decrease elevated p53 K382 acetylation after PMB treatment, further confirming that baicalein inhibits ferroptosis by reducing p53 K382 acetylation via upregulation of SIRT1 expression. In conclusion, these results suggest that baicalein decreases p53 acetylation level by elevating SIRT1, which can then inhibit PMB-induced ferroptosis and ultimately attenuates AKI.

Use of albumin infusion for cirrhosis-related complications: An international position statement

Background & Aims

Numerous studies have evaluated the role of human albumin (HA) in managing various liver cirrhosis-related complications. However, their conclusions remain partially controversial, probably because HA was evaluated in different settings, including indications, patient characteristics, and dosage and duration of therapy.

Methods

Thirty-three investigators from 19 countries with expertise in the management of liver cirrhosis-related complications were invited to organise an International Special Interest Group. A three-round Delphi consensus process was conducted to complete the international position statement on the use of HA for treatment of liver cirrhosis-related complications.

Results

Twelve clinically significant position statements were proposed. Short-term infusion of HA should be recommended for the management of hepatorenal syndrome, large volume paracentesis, and spontaneous bacterial peritonitis in liver cirrhosis. Its effects on the prevention or treatment of other liver cirrhosis-related complications should be further elucidated. Long-term HA administration can be considered in specific settings. Pulmonary oedema should be closely monitored as a potential adverse effect in cirrhotic patients receiving HA infusion.

Conclusions

Based on the currently available evidence, the international position statement suggests the potential benefits of HA for the management of multiple liver cirrhosis-related complications and summarises its safety profile. However, its optimal timing and infusion strategy remain to be further elucidated.

Impact and implications

Thirty-three investigators from 19 countries proposed 12 position statements on the use of human albumin (HA) infusion in liver cirrhosis-related complications. Based on current evidence, short-term HA infusion should be recommended for the management of HRS, LVP, and SBP; whereas, long-term HA administration can be considered in the setting where budget and logistical issues can be resolved. However, pulmonary oedema should be closely monitored in cirrhotic patients who receive HA infusion.

The incidence of acute renal failure and high mortality rate in elderly patients hospitalized with community acquired pneumonia

Community acquired pneumonia is associated with high mortality and health care costs, especially in old age. The clinical presentation of pneumonia in the elderly may be asymptomatic or atypical. One of the known complication is an acute kidney injury. The purpose of our study was to estimate the incidence of this complication in elderly patients hospitalized with pneumonia in our geriatric hospital. From a group of 180 elderly patients hospitalized with community-acquired pneumonia 34.4 % developed acute kidney injury. In this group, 51.6 % of patients died compared to 14.4 % in the group of patients without acute kidney injury (p < 0.001). The lower level of e-GFR was significantly associated with mortality (p < 0.001): out of seven patients with e-GFR level of 15-29 mg/mmol, five patients died (71.4 %). Elderly patients with community-acquired pneumonia suffering acute kidney injury experienced worse in-hospital outcomes; mortality rate was significantly higher in our study. We found a relationship between low level of e-GFR and mortality. Clinicians should be alert for early detection and prevention of kidney injury in patients admitted with pneumonia.

[Blunt abdominal trauma in children and adolescents: treatment concepts in the acute phase]

Fatal accidents due to blunt force trauma are the leading cause of death in children and adolescents [1]. Abdominal trauma is the third most common cause of death after traumatic brain injury and thoracic injuries [2]. Abdominal injury is seen in approximately 2-5% of children involved in accidents [3]. Blunt abdominal injuries are common sequelae of traffic accidents (for example as seat belt injury), falls, and sports accidents. Penetrating abdominal injuries are rare in central Europe. Spleen, liver, and kidney lacerations are the most common injuries after blunt abdominal trauma [4]. In most situations, nonoperative management (NOM) has become the gold standard with the surgeon leading the multidisciplinary treatment [5].

Antioxidant and Anti-inflammatory Effects of α-Lipoic Acid on Lipopolysaccharide-induced Oxidative Stress in Rat Kidney

α-Lipoic acid (α-LA) is a naturally occurring organosulfur component. Oxidative stress plays an essential role in the pathogenesis of various diseases, such as kidney and cardiovascular diseases, diabetes, neurodegenerative disorders, cancer and aging. Kidneys are especially vulnerable to oxidative stress and damage. The aim of the study was to evaluate the effect of α-LA on lipopolysaccharide (LPS)-induced oxidative stress parameters in rat kidneys. The experimental rats were divided into four groups: I-control (0.9% NaCl i.v.); II-α-LA (60 mg/kg b.w. i.v.); III-LPS (30 mg/kg b.w. i.v.); and IV-LPS + LA (30 mg/kg b.w. i.v. and 60 mg/kg b.w. i.v., respectively). In kidney homogenates the concentration of thiobarbituric acid reactive substances (TBARS), hydrogen peroxide (H₂O₂), sulfhydryl groups (-SH), total protein, superoxide dismutase (SOD), total glutathione (tGSH), reduced glutathione (GSH), glutathione disulphide (GSSG) and the GSH/GSSG ratio were determined. In addition, the levels of tumour necrosis factor (TNF)-α, and interleukin (IL)-6 were measured to assess inflammation and was estimated kidney oedema. Studies have shown that α-LA administered after LPS administration attenuated kidney oedema and significantly decreased TBARS, H₂O₂, TNF-α, and IL-6 levels in rat kidneys. α-LA also resulted in increase -SH group, total protein, and SOD levels and ameliorated the GSH redox status when compared to the LPS group. The results suggest that α-LA plays an important role against LPS-induced oxidative stress in kidney tissue as well as downregulating the expression of pro-inflammatory cytokines.

Estradiol protects female mice from hyperuricemia induced by PCB138 exposure

Polychlorinated biphenyls (PCBs) are a type of persistent organic pollutant (POP). Our previous study demonstrated that exposure to 0.5-50 μg/kg bw PCB138 during postnatal days (PND) 3-21 led to elevated serum uric acid (UA) levels and kidney injury in adult male mice. Given that the prevalence of hyperuricemia (HUA) is significantly lower in women than in men, it is worth investigating whether POP-induced HUA and its secondary kidney injury have sexual dimorphism. Herein, we exposed female mice to 0.5-50 μg/kg bw PCB138 during PND 3-21, resulting in elevated serum UA levels, but without causing significant kidney damage. Concurrently, we found a negative correlation between serum 17β-estradiol (E2) and serum UA levels. We also observed down-regulation of estrogen receptor (ER) protein levels in the kidneys of the PCB138-exposed groups. Furthermore, our study showed that E2 rescued the increased UA level and cytotoxicity caused by HUA in human renal tubular epithelial (HK-2) cells. Collectively, our findings suggest that E2 likely plays a crucial protective role in PCB138-induced HUA and kidney injury in female mice. Our research highlights the existence of sexual dimorphism in kidney injury secondary to HUA induced by POPs, which could provide guidance for individuals of different genders in preventing kidney injury caused by environmental factors.

Cadmium induced time-dependent kidney injury in common carp via mitochondrial pathway: Impaired mitochondrial energy metabolism and mitochondrion-dependent apoptosis

Toxic effect of heavy metal cadmium (Cd) on fish kidneys had been reported. Mitochondrion is an important organelle for maintaining kidney function, while its role in Cd-induced kidney injury in common carp remained unclarified. In this experiment, we established a poisoning model of common carp with Cd exposure (0.26 mg/L) for 15, 30, and 45 days. Serum biochemistry determination, histological observation, TUNEL assay, qRT-PCR, Western blot, and integrated biomarker response (IBR) were applied to assess the nephrotoxicity of Cd to common carp. Our results displayed that Cd exposure increased the levels of serum biochemical indexes (UREA, CRE, and UA), indicating kidney injury. We further revealed via histological observation that Cd damaged structural integrity of kidneys, as evidenced by renal glomerulus and renal tubular injury, hallmark phenotypes of apoptosis, and mitochondrial damage, suggesting that mitochondria damage and apoptosis were involved in Cd-induced kidney injury. Moreover, Cd exposure decreased ATPase (Na⁺/K⁺-ATPase, Ca²⁺-ATPase, Mg²⁺-ATPase, and Ca²⁺Mg²⁺-ATPase) activities as well as PGC-1a and Mfn2 levels, while increased Drp1 and PINK1 levels as well as LC3-II/LC3-I ratio, which indicated that Cd-impaired renal energy metabolism was related to mitochondrial dysfunction. Additionally, we found that Cd induced oxidative stress (abnormal levels of SOD, CAT, GPX, MDA, and H₂O₂) in kidneys, which was involved in triggering mitochondrial dysfunction and further impairing mitochondrial energy metabolism. Moreover, the occurrence of mitochondria-dependent apoptosis was found after Cd-exposure in common carp kidneys, as indicated by enhanced levels of Bax, CytC, APAF1, Caspase-9, and Caspase-3, while declined level of Bcl-2. Subsequently, we confirmed a time-dependent nephrotoxicity of Cd to common carp via IBR assessment. In conclusion, Cd induced time-dependent nephrotoxicity in common carp via mitochondrial pathway. This mitochondria-oriented study shed light on underlying mechanisms of Cd-induced renal pathologies and provided a theoretical basis for evaluating Cd toxicity to aquatic organisms.

Rutin protects against gamma-irradiation and malathion-induced oxidative stress and inflammation through regulation of mir-129-3p, mir-200C-3p, and mir-210 gene expressions in rats' kidney

Kidney injury represents a global concern, leading to chronic kidney disease. The organophosphate insecticide malathion (MT) demonstrates environmental disturbance and impairment of different mammalian organs, including kidneys. Likewise, gamma-irradiation (IRR) provokes destructive effects in the kidneys. Rutin is a flavonoid glycoside that exhibits nephro-protective and radio-protective properties. This manuscript focused on investigating the protective response of rutin on MT- and IRR-triggered kidney injury in rats. Rats were randomly divided into eight groups of twelve: G1 (C), control; G2 (Rutin), rutin-treated rats; G3 (IRR), gamma-irradiated rats; G4 (MT), malathion-treated rats; G5 (IRR/MT), gamma-irradiated rats treated with malathion; G6 (IRR/Rutin), gamma-irradiated rats treated with rutin; G7 (MT/Rutin), rats treated with malathion and rutin; and G8 (IRR/MT/Rutin), gamma-irradiated rats treated with malathion and rutin, every day for 30 days. The results demonstrated that rutin treatment regulated the biochemical parameters, the oxidative stress, the antioxidant status, and the inflammatory responses due to the down-regulation of the renal NF-κB p65 protein expression. Moreover, it amended the activity of acetylcholinesterase (AchE), angiotensin ACE I, and ACE II-converting enzymes. Besides, it regulated the iNOS, eNOS, miR-129-3p, miR-200c, and miR-210 gene expressions and bradykinin receptor (B1R and B2R) protein expressions. Histopathological examinations of the kidney tissue confirmed these investigated results. It could be concluded that rutin demonstrated nephro/radioprotection and counteracted the toxicological effects triggered in the kidney tissues of IRR, MT, and IRR/MT intoxicated rats, via regulating miR-129-3p, miR-200c-3p, and miR-210-3p gene expressions, which consequently regulated B2R protein expressions, ACE II activity, and HIF-1α production, respectively.

Long-term oral administration of Asarum heterotropoides f. mandshuricum (Maxim.) Kitag. decoction and its aristolochic acid analogs do not cause renal toxicity in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Asarum heterotropoides f. mandshuricum (Maxim.) Kitag. (AH) is widely used to treat influenza, COVID-19, allergic rhinitis, headache, toothache, rheumatoid arthritis, and peptic ulcer. However, its clinical use is controversial due to the concern of aristolochic acid nephropathy (AAN) caused by its component aristolochic acid analogs (AAs).

AIM OF THE STUDY

The chronic toxicity of AH decoction and its main components AA IVa (AA-IVa) and aristolactam I (AL-I) was evaluated in mice.

MATERIALS AND METHODS

AAs contents in AH were quantitated by liquid chromatography-mass spectrometry. A parallel design was employed to examine the potential chronic toxicity of AH decoction at doses equivalent to 0.5, 1.6, and 5.0 g/kg AH (approximately 10-100 times the clinical doses for humans) and its major AA components at doses equivalent to that in 5.0 g/kg AH to mice after consecutive daily oral administration for 12 and 24 weeks, and at 32 weeks after withdrawal for 8 weeks.

RESULTS

AH crude herb contained 2.18 μg/g of AA-I, 48.49 μg/g of AA-IVa, and 14.0 μg/g of AL-I. AH decoction contained 5.45 μg/g of AA-IVa and 2.71 μg/g of AL-I. None of AA-II and AA-IIIa were detected in AH. After long-term administration of AH decoction and its major components AA-IVa and AL-I, mice showed no signs of illness or body weight changes. In addition, biochemical and pathohistological examinations showed that long-term administration of AH decoction and its major components AA-IVa and AL-I did not alter 1) serum levels of glutamic-pyruvic transaminase, glutamic oxalacetic transaminase, alkaline phosphatase, creatinine, and urea nitrogen, 2) renal tissue mRNA expression of kidney injury molecule 1 and neutrophil gelatinase-associated lipocalin, and 3) pathological morphology in the mouse liver, kidney, stomach, and bladder.

CONCLUSIONS

AH has no obvious toxicity to mice and is relatively safe when it is used in the form of decoction. AA-IVa and AL-I, the two major AAs in AH, are not toxic to mice at the dose equivalent to that in the high dose of AH decoction. Considering the limited toxicological data on AH, we recommend that AH decoction medication should not overdose and the duration should not be too long.

The microplastics exposure induce the kidney injury in mice revealed by RNA-seq

Microplastics (MPs) may pollute drinking water, accumulate in the food chain, and release toxic chemicals that may cause a variety of diseases. The detrimental effects of MPs on kidney injury and fibrosis under long-term accumulation have not been fully documented. In this study, mice were exposed to MPs with three different diameters (80 nm, 0.5 µm, and 5 µm) to investigate the detrimental influences of MPs on the kidney. The results showed that MPs of different diameters caused varying degrees of injury to the murine kidney. MPs exposure can induce an inflammatory response, oxidative stress, and cell apoptosis in the kidney and induce kidney injury, which ultimately promotes kidney fibrosis. Furthermore, transcriptome data revealed that chronic exposure to MPs could alter the expressions of multiple genes related to immune response (80 nm) and circadian rhythm (0.5 µm, and 5 µm). Overall, our data provide new evidence and potential research for investigating the harm of MPs to kidney of mammals and even humans.

Construction and evaluation of risk prediction model for kidney injury in patients treated with PD-1 inhibitors

OBJECTIVE

Construction of a nomogram model for predicting the risk of kidney injury associated with programmed cell death protein-1 (PD-1) inhibitors.

METHODS

Patients using PD-1 inhibitors from January 2018 to January 2021 in our center were retrospectively analyzed and followed up until January 2022. Kidney injury was defined as acute kidney disease and disorders (AKD). Univariate and multivariate logistic regression models were used to identify independent risk factors for PD-1 inhibitor associated kidney injury, and nomogram prediction models were further established.

RESULTS

A total of 447 patients were included, of whom 71 patients developed AKD. Multivariate logistic regression analysis identified comorbid extrarenal immune related adverse events (irAEs), lower baseline hemoglobin (Hb) level, higher baseline serum creatinine (SCr) and direct bilirubin (DBIL) level as independent risk factors for the development of PD-1 inhibitor associated kidney injury (P < 0.05). A nomogram prediction model was established based on the above independent risk factors. The area under the receiver operating characteristic (ROC) curve (AUC) of the training set and validation set of the model was 0.703 (95% CI 0.628~0.777), 0.791 (95% CI 0.671~0.911), respectively, which suggested that the predictive ability of the model was acceptable. The calibration curves for both the training and validation sets hovered around the ideal line of 45 degrees, suggesting good calibration of the model. Clinical decision curve analysis (DCA) showed that the constructed nomogram curve was far from the two polar end lines, suggesting better clinical benefit of the model.

CONCLUSION

There are many independent risk factors of PD-1 inhibitor related kidney injury. The predictive ability and calibration of the nomogram model established in this study were acceptable and had clinical utility.

Linalool prevents kidney damage by inhibiting rifampicin-induced oxidative stress and apoptosis

Today, kidney diseases are increasing day by day and life quality is decreasing. In hospitalized patients of all ages, acute kidney injury (AKI) is commonly observed and associated with high rates of morbidity and mortality. Rifampicin (RF) or rifampin is an antibiotic drug from the rifamycin group with a bactericidal effect. RF causes acute kidney injury, often anemia, thrombocytopenia, liver damage and side effect such as cell death. RF causes tissue damage by means of oxidative stress and apoptosis. Thus, in this study, it was examined whether linalool (LN) which had antinociceptive, antimicrobial, antioxidant and anti-inflammatory effects, was beneficial for kidney damage in order to eliminate the side effects of RF. NGAL mRNA, creatinine (Cr), blood urea nitrogen (BUN), Caspase 9 (CAS-9) and nuclear factor-κB (NF-κB) levels increased in the group treated with RF compared to the control group, while the levels of albumin, uric acid and total protein were decreased in the RF-treated group. NGAL mRNA, BUN, Cr, CAS-9 and NF-κB levels decreased significantly in RF+LN administered rats, while it was observed that there was an increase in the levels of albumin, uric acid and total protein. From the results obtained, it was observed that LN was determined to be very effective in preventing tissue damage in kidneys caused by oxidative stress by RF.

Avasopasem manganese (GC4419) protects against cisplatin-induced chronic kidney disease: An exploratory analysis of renal metrics from a randomized phase 2b clinical trial in head and neck cancer patients

Head and neck squamous cell carcinoma (HNSCC) patients treated with high-dose cisplatin concurrently with radiotherapy (hdCis-RT) commonly suffer kidney injury leading to acute and chronic kidney disease (AKD and CKD, respectively). We conducted a retrospective analysis of renal function and kidney injury-related plasma biomarkers in a subset of HNSCC subjects receiving hdCis-RT in a double-blinded, placebo-controlled clinical trial (NCT02508389) evaluating the superoxide dismutase mimetic, avasopasem manganese (AVA), an investigational new drug. We found that 90 mg AVA treatment prevented a significant reduction in estimated glomerular filtration rate (eGFR) three months as well as six and twelve months after treatment compared to 30 mg AVA and placebo. Moreover, AVA treatment may have allowed renal repair in the first 22 days following cisplatin treatment as evidenced by an increase in epithelial growth factor (EGF), known to aid in renal recovery. An upward trend was also observed in plasma iron homeostasis proteins including total iron (Fe-blood) and iron saturation (Fe-saturation) in the 90 mg AVA group versus placebo. These data support the hypothesis that treatment with 90 mg AVA mitigates cisplatin-induced CKD by inhibiting hdCis-induced renal changes and promoting renal recovery.

Athelia rolfsii Exopolysaccharide Protection Against Kidney Injury in Lead-Exposed Mice via Nrf2 Signaling Pathway

This study aimed to explore protective efficacy of Athelia rolfsii exopolysaccharides (AEPS) to mice kidney against lead-exposed injury with a focus on the role of nuclear factor erythroid-2-related factor 2 (Nrf2) signaling pathway. Lead accumulation in the kidney induces oxidative stress which causes low antioxidant activity, abnormal pathological changes, and apoptosis. Here, the changes in lead levels in the kidney and whole blood proved that AEPS inhibited lead accumulation. It might be related to AEPS enhancing glutathione (GSH) levels and glutathione-s-transferase (GST) activities, as well as the protein abundances of multidrug resistance-associated protein 1 (MRP1) and multidrug resistance-associated protein 2 (MRP2). Moreover, AEPS increased antioxidant activity by upregulating superoxide dismutase (SOD), catalase (CAT) activities, downregulating malondialdehyde (MDA) levels. It also restored kidney function by decreasing blood urea nitrogen (BUN) and creatinine (CRE) levels in the serum. Histopathologic analysis showed that AEPS alleviated the kidney injury induced by lead, too. AEPS also showed anti-apoptosis effect by downregulating caspase-3 and bax expression and upregulating bcl-2 expression. Importantly, AEPS activated Nrf2 signaling pathway by promoting nuclear translocation of Nrf2. However, all-trans-retinoic acid (ATRA), an Nrf2 inhibitor, reversed the effects on AEPS to activation of Nrf2, enhancement of antioxidant, alleviation of kidney injury, restoration of kidney function, prevention of apoptotic, and facilitation of lead exclusion. In brief, AEPS showed kidney protective effect and facilitated lead-expulsion in an Nrf2-dependent manner.

Ameliorative effect of cheqianzi decoction on hyperuricemia and kidney injury and underlying mechanism in rats

Cheqianzi Decoction (CQD) is a Traditional Chinese Medicine (TCM) formula comprising four herbs and is recorded in the Ancient Materia Medica "Shengji Zonglu". Individually, these four herbs have been shown to reduce uric acid (UA) levels, to treat hyperuricemia (HUA), and alleviate kidney damage. However, the therapeutic efficacy of the CQD and related mechanism are not yet clear. In this study, high performance liquid chromatography (HPLC) analysis confirmed that the contents of the chemical components of the four herbal medicines were in accordance with the provisions of the Chinese Pharmacopoeia. A total of 99 potential targets were identified in the network pharmacology analysis of CQD, indicating its involvement in the regulation of inflammatory and apoptotic signaling pathways, and potential value for treating HUA and alleviating kidney injury. In vivo pharmacodynamic studies showed that compared with the Model group, significantly decreased levels of serum uric acid (SUA), serum creatinine (SCr), blood urea nitrogen (BUN) (all P < 0.05), and inflammatory factors (P < 0.01) were detected in the CQD group. Quantitative real-time PCR and Western blot analyses showed that compared with the Model group, adenosine triphosphate (ATP)-binding cassette efflux transporter G2 (ABCG2) expression in the CQD group was significantly upregulated (P < 0.01) at both the mRNA and protein levels, while mRNA expression of Caspase3 and NOD-like receptor family member 3 (NLRP3) (P < 0.05) and protein expression of NLRP3 (P < 0.01) were significantly downregulated. In conclusion, CQD promotes UA excretion by activating ABCG2, and induces inflammasome NLRP3-mediated reduction in inflammatory and apoptotic factors to achieve renal protection. Thus, our findings indicate the therapeutic potential of CQD in HUA with kidney injury.

Environmental heat exposure and implications on renal health of pediatric communities in the dry climatic zone of Sri Lanka: An approach with urinary biomarkers

Prolonged heat exposure during outdoor physical exertion can result in adverse renal health outcomes, and it is also supposed to be a driver of chronic kidney disease of uncertain etiology (CKDu) in tropical regions. School students are more likely to experience high heat exposure during outdoor sports practices, and the current knowledge on potential renal health outcomes associated with heat exposure carries many knowledge gaps. Hence, the present study aimed to perform biomarker-based assessment of the likelihood of pediatric renal injury focusing the communities in the dry climatic zone in Sri Lanka, where it prevails relatively harsh climate and high prevalence of CKDu. School students who engaged in regular outdoor sports practices (high-heat exposure), and an age-matched control of students who did not engage in sports practices (low-heat exposure) from four educational zones: Padavi Sripura (N = 159) and Medirigiriya (N = 171), Uhana (N = 165) and Thanamalwila (N = 169) participated in this cross-sectional study representing CKDu endemic and non-endemic regions. Effective temperature (ET), wet-bulb globe temperature (WBGT), heat index (HI) and humidex were used for comparison of thermal comfort in the environment. The intensity of environmental heat measured by thermal comfort indices showed no significant difference (p > 0.05) among the study regions. Urinary kidney injury molecule (KIM-1) and albumin-creatinine ratio (ACR) in participants with high heat exposure did not differ significantly from those in the control groups in the four study zones, where urinary neutrophil gelatinase-associated lipocalin showed substantial differences in some groups. Irrespective of heat exposure, increased KIM-1 excretion was observed (p < 0.01) in participants of CKDu endemic regions compared to those in non-endemic areas. Within the context of our findings, there is no plausibly strong evidence to establish potential association of heat exposure with the likelihood of developing renal injury or abnormal renal outcomes in dry zone school students in Sri Lanka.

ChREBP-β/TXNIP aggravates frucose-induced renal injury through triggering ferroptosis of renal tubular epithelial cells

High fructose intake is an essential risk factor for kidney injury. However, the specific mechanism underlying high fructose-induced kidney injury remains unclarified. Carbohydrate response element-binding protein (ChREBP) is a key transcriptional activator that regulates fructose metabolism. ChREBP-β exhibits sustained activity due to the lack of a low glucose inhibitory domain, and is thus described as the active form of ChREBP. In this study, a mouse model with specific overexpression of ChREBP-β in the renal tubule was established by using the Cre/LoxP method. Quantitative proteomic analysis and experimental verification results suggest that ChREP-β overexpression leads to ferroptosis of renal tubular epithelial cells and kidney injury. ChREPB-β promotes the gene transcription of thioredoxin-interacting protein (TXNIP) and thereby increases its expression level. TXNIP is associated with activation of ferroptosis. TXNIP can initiate ferroptosis and eventually contribute to high fructose-induced renal tubular epithelial cell damage. Through down-regulating ChREBP-β, metformin can inhibit gene transcription of TXNIP, attenuate high fructose-induced ferroptosis in renal tubular epithelial cells, and alleviate kidney injury. In conclusion, ChREBP-β mediates fructose-induced ferroptosis of renal tubular epithelial cells, and metformin with a ChREBP-β inhibitory effect may be a potential treatment for ferroptosis of renal tubular epithelial cells.

Blockade of Indoleamine 2,3-Dioxygenase attenuates lipopolysaccharide-induced kidney injury by inhibiting TLR4/NF-κB signaling

Blockade of indoleamine 2,3-dioxygenase (IDO) has been shown to alleviate lipopolysaccharide (LPS)-induced endotoxic shock and reduce sepsis mortality, but its effect on LPS-induced kidney damage has not been reported. Herein, we established a mouse kidney injury model by intraperitoneal injection of 10 mg/kg LPS and established an in vitro renal tubular epithelial cell injury model by stimulating TCMK-1 cells with 10 mg/L LPS. We found that pretreatment with 1-methyl tryptophan (1-MT), an IDO inhibitor, significantly improved LPS-induced mouse survival, and IDO knockout (KO) mice also had higher survival rates after LPS exposure than wild-type mice. At the same time, IDO KO or pretreatment with 1-MT not only reduced serum creatinine, blood urea nitrogen, renal tubular injury pathological score, but also inflammatory factors and oxidative stress status in serum or kidney of LPS-exposed mice. In vitro, blockade of IDO with 1-MT significantly inhibited LPS-induced apoptosis, inflammation and oxidative stress in TCMK-1 cells. In addition, blockade of IDO significantly inhibited LPS-activated TLR4/NF-κB signaling pathway in kidney of mice or in TCMK-1 cells. In conclusion, our results suggested that blockade of IDO attenuated kidney inflammation, apoptosis and oxidative stress to protect against LPS-induced septic kidney injury via inhibiting the TLR4/NF-κB signaling pathway.