Nephroprotective effect of Ginsenoside Rg1 in lipopolysaccharide-induced sepsis in mice through the SIRT1/NF-κB signaling.

INTRODUCTION: During sepsis, the kidney is one of the most vulnerable organs. Sepsis-associated acute kidney injury (S-AKI) is hallmarked by renal inflammation, apoptosis, and oxidative injury. Ginsenoside Rg1 (Rg1) is a natural product that possesses abundant pharmacological actions and protects against many sepsis-related diseases. Nevertheless, its role and related mechanism in S-AKI remain to be determined. MATERIALS AND METHODS: S-AKI was induced using lipopolysaccharide (LPS, 10 mg/kg) via a single intraperitoneal injection. Rg1 (200 mg/kg) was intraperitoneally administered for 3 consecutive days before LPS treatment. For histopathological examination, murine kidney tissues were stained with hematoxylin and eosin. Tubular injury score was calculated to evaluate kidney injury. Serum creatinine and BUN levels were measured for assessing renal dysfunction. The levels and activities of oxidative stress markers (MDA, 4-HNE, PC, GSH, SOD, and CAT) in renal tissue were measured by corresponding kits. Renal cell apoptosis was detected by TUNEL staining. The protein levels of apoptosis-related markers (Bcl-2, Bax, and Cleaved caspase-3), proinflammatory factors, SIRT1, IκBα, p-NF-κB p65, and NF-κB p65 in kidneys were determined using western blotting. Immunofluorescence staining was employed to assess p-NF-κB p65 expression in renal tissues. RESULTS: LPS-induced injury of kidneys and renal dysfunction in mice were ameliorated by Rg1. Rg1 also impeded LPS-evoked renal cell apoptosis in kidneys. Moreover, Rg1 attenuated LPS-triggered inflammation and oxidative stress in kidneys by inhibiting proinflammatory cytokine release, enhancing antioxidant levels and activities, and reducing lipid peroxidation. However, all these protective effects of Rg1 in LPS-induced AKI mice were reversed by EX527, an inhibitor of sirtuin 1 (SIRT1). Mechanistically, Rg1 upregulated SIRT1 protein expression, increased SIRT1 activity, and inactivated NF-κB signaling in the kidney of LPS-induced AKI mice, which was also reversed by EX527. CONCLUSIONS: Rg1 ameliorates LPS-induced kidney injury and suppresses renal inflammation, apoptosis, and oxidative stress in mice via regulating the SIRT1/NF-κB signaling.

Renoprotective effect of diacetylrhein on diclofenac-induced acute kidney injury in rats via modulating Nrf2/NF-κB/NLRP3/GSDMD signaling pathways.

Diclofenac (DF)-induced acute kidney injury (AKI) is characterized by glomerular dysfunction and acute tubular necrosis. Due to limited treatment approaches, effective and safe drug therapy to protect against such AKI is still needed. Diacetylrhein (DAR), an anthraquinone derivative, has different antioxidant and anti-inflammatory properties. Therefore, the aim of the current study was to investigate the renoprotective effect of DAR on DF-induced AKI while elucidating the potential underlying mechanism. Our results showed that DAR (50 and 100 mg/kg) markedly abrogated DF-induced kidney dysfunction decreasing SCr, BUN, serum NGAL, and serum KIM1 levels. Moreover, DAR treatment remarkably maintained renal redox balance and reduced the levels of pro-inflammatory biomarkers in the kidney. Mechanistically, DAR boosted Nrf2/HO-1 antioxidant and anti-inflammatory response in the kidney while suppressing renal TLR4/NF-κB and NLRP3/caspase-1 inflammatory signaling pathways. In addition, DAR markedly inhibited renal pyroptosis via targeting of GSDMD activation. Collectively, this study confirmed that the interplay between Nrf2/HO-1 and TLR4/NF-κB/NLRP3/Caspase-1 signaling pathways and pyroptotic cell death mediates DF-induced AKI and reported that DAR has a dose-dependent renoprotective effect on DF-induced AKI in rats. This effect is due to powerful antioxidant, anti-inflammatory, and anti-pyroptotic activities that could provide a promising treatment approach to protect against DF-induced AKI.

Dehydroandrographolide facilitates M2 macrophage polarization by downregulating DUSP3 to inhibit sepsis-associated acute kidney injury.

BACKGROUND: Sepsis is perceived as lethal tissue damage and significantly increases mortality in combination with acute kidney injury (AKI). M2 macrophages play important roles in the secretion of anti-inflammatory and tissue repair mediators. We aimed to study the role of Dehydroandrographolide (Deh) in sepsis-associated AKI in vitro and in vivo through lipopolysaccharide (LPS)-induced macrophages model and cecal ligation and puncture-induced AKI mice model, and to reveal the mechanism related to M2 macrophage polarization. METHODS: Enzyme-linked immunosorbent assay kits were used to assess the levels of inflammatory factors. Expression of markers related to M1 macrophages and M2 macrophages were analyzed. Additionally, dual specificity phosphatase 3 (DUSP3) expression was tested. Cell apoptosis was evaluated by flow cytometry analysis and terminal-deoxynucleotidyl transferase-mediated nick end labeling staining. Moreover, renal histological assessment was performed by using hematoxylin and eosin staining. RESULTS: Deh reduced inflammation of THP-1-derived macrophages exposed to LPS. Besides, Deh induced the polarization of M1 macrophages to M2 and downregulated DUSP3 expression in THP-1-derived macrophages under LPS conditions. Further, DUSP3 overexpression reversed the impacts of Deh on the inflammation and M2 macrophages polarization of THP-1-derived macrophages stimulated by LPS. Additionally, human proximal tubular epithelial cells (HK-2) in the condition medium from DUSP3-overexpressed THP-1-derived macrophages treated with LPS and Deh displayed decreased viability and increased apoptosis and inflammation. The in vivo results suggested that Deh improved the renal function, ameliorated pathological injury, induced the polarization of M1 macrophages to M2, suppressed inflammation and apoptosis, and downregulated DUSP3 expression in sepsis-induced mice. CONCLUSION: Deh facilitated M2 macrophage polarization by downregulating DUSP3 to inhibit septic AKI.

[Clinical features of acyclovir encephalopathy without acute kidney injury].

INTRODUCTION: Few reports have described acyclovir (ACV) encephalopathy without acute kidney injury (AKI). OBJECTIVE: This study clarified the clinical features of ACV encephalopathy without AKI compared to that with AKI. METHODS: Creatinine (Cre) levels were measured on admission. After admission, Cre was measured in a timely manner for the first seven hospital days. The minimum Cre level in these measurements was then determined. ACV encephalopathy was defined when two criteria were met: 1) neurological symptoms appeared after valacyclovir (VACV) administration, and 2) neurological symptoms improved after VACV discontinuation. AKI was defined when the Cre level on admission was >1.5 times higher than the minimum Cre level. The subjects were divided into AKI and non-AKI groups based on these findings. RESULTS: Eighteen patients had ACV encephalopathy (5 males, mean age 81.3±5.5 years old). All patients were prescribed VACV 3,000 mg/day. The minimum Cre was 1.93±1.76 mg/dL. AKI occurred in 10 (56.6%) patients. VACV was discontinued in all patients, and emergency hemodialysis treatment was administered in 10 (55.6%) patients. All patients recovered. Compared to the AKI group, the non-AKI group had a lower history of taking a Ca-blocker (33.3% vs 80.0%, p=0.092), a lower rate of emergency dialysis (16.9% vs 70.0%, p=0.059) and a longer time to clinical improvement (3.67±1.86 vs 2.20±0.63 days, p=0.073). CONCLUSION: ACV encephalopathy without AKI is characterized by a low rate of emergency dialysis, which may be linked to a prolonged duration of symptoms.

TAK-242 improves sepsis-associated acute kidney injury in rats by inhibiting the TLR4/NF-κB signaling pathway.

OBJECTIVE: This study was designed to observe the effect of toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) pathway activity on sepsis-associated acute kidney injury (SA-AKI), thereby providing new considerations for the prevention and treatment of SA-AKI. METHODS: The rats were divided into Sham, cecal ligation and puncture (CLP), CLP + vehicle, and CLP + TAK-242 groups. Except the Sham group, a model of CLP-induced sepsis was established in other groups. After 24 h, the indicators related to kidney injury in blood samples were detected. The pathological changes in the kidneys were observed by hematoxylin-eosin staining, and tubular damage was scored. Oxidative stress-related factors, mitochondrial dysfunction-related indicators in each group were measured; the levels of inflammatory factors in serum and kidney tissue of rats were examined. Finally, the expression of proteins related to the TLR4/NF-κB signaling pathway was observed by western blot. RESULTS: Compared with the CLP + vehicle and CLP + TAK-242 groups, the CLP + TAK-242 group reduced blood urea nitrogen (BUN), creatinine (Cr), cystatin-C (Cys-C), reactive oxygen species (ROS), malondialdehyde (MDA), and inflammatory factors levels (p < 0.01), as well as increased superoxide dismutase (SOD) activity of CLP rats (p < 0.01). Additionally, TAK-242 treatment improved the condition of CLP rats that had glomerular and tubular injuries and mitochondrial disorders (p < 0.01). Further mechanism research revealed that TAK-242 can inhibit the TLR4/NF-κB signaling pathway activated by CLP (p < 0.01). Above indicators after TAK-242 treatment were close to those of the Sham group. CONCLUSION: TAK-242 can improve oxidative stress, mitochondrial dysfunction, and inflammatory response by inhibiting the activity of TLR4/NF-κB signaling pathway, thereby preventing rats from SA-AKI.

Interleukin-2/anti-interleukin-2 immune complex attenuates cold ischemia-reperfusion injury after kidney transplantation by increasing renal regulatory T cells.

BACKGROUND: Cold ischemia-reperfusion injury (IRI) is an unavoidable complication of kidney transplantation. We investigated the role of regulatory T cells (Treg) in cold IRI and whether the interleukin (IL)-2/anti-IL-2 antibody complex (IL-2C) can ameliorate cold IRI. METHODS: We developed a cold IRI mouse model using kidney transplantation and analyzed the IL-2C impact on cold IRI in acute, subacute and chronic phases. RESULTS: Treg transfer attenuated cold IRI, while Treg depletion aggravated cold IRI. Next, IL-2C administration prior to IRI mitigated acute renal function decline, renal tissue damage and apoptosis and inhibited infiltration of effector cells into kidneys and pro-inflammatory cytokine expression on day 1 after IRI. On day 7 after IRI, IL-2C promoted renal regeneration and reduced subacute renal damage. Furthermore, on day 28 following IRI, IL-2C inhibited chronic fibrosis. IL-2C decreased reactive oxygen species-mediated injury and improved antioxidant function. When IL-2C was administered following IRI, it also increased renal regeneration with Treg infiltration and suppressed renal fibrosis. In contrast, Treg depletion in the presence of IL-2C eliminated the positive effects of IL-2C on IRI. CONCLUSION: Tregs protect kidneys from cold IRI and IL-2C inhibited cold IRI by increasing the renal Tregs, suggesting a potential of IL-2C in treating cold IRI. KEY POINTS: Interleukin (IL)-2/anti-IL-2 antibody complex attenuated acute renal injury, facilitated subacute renal regeneration and suppressed chronic renal fibrosis after cold ischemia-reperfusion injury (IRI) by increasing the renal Tregs. IL-2/anti-IL-2 antibody complex decreased reactive oxygen species-mediated injury and improved antioxidant function. This study suggests the therapeutic potential of the IL-2/anti-IL-2 antibody complex in kidney transplantation-associated cold IR.

Prostaglandin Transporter and Dipeptidyl Peptidase-4 as New Pharmacological Targets in the Prevention of Acute Kidney Injury in Diabetes: An In Vitro Study.

The probability of acute kidney injury (AKI) is higher in septic diabetic patients, which is associated with, among other factors, proximal tubular cell (PTC) injury induced by the hypoxic/hyperglycemic/inflammatory microenvironment that surrounds PTCs in these patients. Here, we exposed human PTCs (HK-2 cells) to 1% O2/25 mM glucose/inflammatory cytokines with the aim of studying the role of prostaglandin uptake transporter (PGT) and dipeptidyl peptidase-4 (DPP-4, a target of anti-hyperglycemic agents) as pharmacological targets to prevent AKI in septic diabetic patients. Our model reproduced two pathologically relevant mechanisms: (i) pro-inflammatory PTC activation, as demonstrated by the increased secretion of chemokines IL-8 and MCP-1 and the enhanced expression of DPP-4, intercellular leukocyte adhesion molecule-1 and cyclo-oxygenase-2 (COX-2), the latter resulting in a PGT-dependent increase in intracellular prostaglandin E2 (iPGE2); and (ii) epithelial monolayer injury and the consequent disturbance of paracellular permeability, which was related to cell detachment from collagen IV and the alteration of the cell cytoskeleton. Most of these changes were prevented by the antagonism of PGE2 receptors or the inhibition of COX-2, PGT or DPP-4, and further studies suggested that a COX-2/iPGE2/DPP-4 pathway mediates the pathogenic effects of the hypoxic/hyperglycemic/inflammatory conditions on PTCs. Therefore, inhibitors of PGT or DPP-4 ought to undergo testing as a novel therapeutic avenue to prevent proximal tubular damage in diabetic patients at risk of AKI.

Transient inhibition of sodium-glucose cotransporter 2 after ischemia/reperfusion injury ameliorates chronic kidney disease.

Sodium-glucose cotransporter 2 (SGLT2) inhibitor, dapagliflozin (Dapa), exhibited nephroprotective effects in patients with chronic kidney disease (CKD). We assessed the efficacy of short-term Dapa administration following acute kidney injury (AKI) in preventing CKD. Male Wistar rats were randomly assigned to Sham surgery, bilateral ischemia for 30 minutes (abbreviated as IR), and IR + Dapa groups. Daily treatment with Dapa was initiated just 24 hours after IR and maintained for only 10 days. Initially, rats were euthanized at this point to study early renal repair. After severe AKI, Dapa promptly restored creatinine clearance (CrCl) and significantly reduced renal vascular resistance compared with the IR group. Furthermore, Dapa effectively reversed the mitochondrial abnormalities, including increased fission, altered mitophagy, metabolic dysfunction, and proapoptotic signaling. To study this earlier, another set of rats was studied just 5 days after AKI. Despite persistent renal dysfunction, our data reveal a degree of mitochondrial protection. Remarkably, a 10-day treatment with Dapa demonstrated effectiveness in preventing CKD transition in an independent cohort monitored for 5 months after AKI. This was evidenced by improvements in proteinuria, CrCl, glomerulosclerosis, and fibrosis. Our findings underscore the potential of Dapa in preventing maladaptive repair following AKI, emphasizing the crucial role of early intervention in mitigating AKI long-term consequences.

Pyxinol Fatty Acid Ester Derivatives J16 against AKI by Selectively Promoting M1 Transition to M2c Macrophages.

Acute kidney injury (AKI) is a common, multicause clinical condition that, if ignored, often progresses to chronic kidney disease (CKD) and end-stage kidney disease, with a mortality rate of 40-50%. However, there is a lack of universal treatment for AKI. Inflammation is the basic pathological change of early kidney injury, and inflammation can exacerbate AKI. Macrophages are the primary immune cells involved in the inflammatory microenvironment of kidney disease. Therefore, regulating the function of macrophages is a crucial breakthrough for the AKI intervention. Our team chemically modified pyxinol, an ocotillol-type ginsenoside, to prepare PJ16 with higher solubility and bioavailability. In vitro, using a model of macrophages stimulated by LPS, it was found that PJ16 could regulate macrophage function, including inhibiting the secretion of inflammatory factors, promoting phagocytosis, inhibiting M1 macrophages, and promoting M1 transition to the M2c macrophage. Further investigation revealed that PJ16 may shield renal tubular epithelial cells (HK-2) damaged by LPS in vitro. Based on this, PJ16 was validated in the animal model of unilateral ureteral obstruction, which showed that it improves renal function and inhibits renal tissue fibrosis by decreasing inflammatory responses, reducing macrophage inflammatory infiltration, and preferentially upregulating M2c macrophages. In conclusion, our study is the first to show that PJ16 resists AKI and fibrosis by mechanistically regulating macrophage function by modulating the phenotypic transition from M1 to M2 macrophages, mainly M2c macrophages.

Arylacryl amides: Design, synthesis and the protection against cisplatin-induced acute kidney injury via TLR4/STING/NF-κB pathway.

Arylpropionic ester scaffold was found as anti-inflammatory agents for the treatment and prevention of acute kidney injury (AKI). To further study the structure-activity relationship (SAR) of this scaffold, a series of acryl amides were designed, synthesized, and evaluated their anti-inflammation. Of these, compound 9d displayed the protective effect on renal tubular epithelial cells to significantly enhance the survival rate through inhibiting NF-κB phosphorylation and promoting cell proliferation in cisplatin-induced HK2 cells. Furthermore, 9d can interact with TLR4 to inhibit TLR4/STING/NF-κB pathway in the RAW264.7 cell. In vivo AKI mice model, 9d significantly downregulated the level of serum creatinine (Scr), blood urea nitrogen (BUN) and the inflammatory factors (IL-1ß, IL-6, TNF-α) to improve kidney function. Morphological and KIM-1 analyses showed that 9d alleviated cisplatin-induced tubular damage. In a word, 9d was a promising lead compound for preventive and therapeutic of AKI.

Renoprotective effects of laxative linaclotide: Inhibition of acute kidney injury and fibrosis in a rat model of renal ischemia-reperfusion.

Ischemia-reperfusion (I/R) leads to tissue damage in transplanted kidneys, resulting in acute kidney injury (AKI) and chronic graft dysfunction, which critically compromises transplant outcomes, such as graft loss. Linaclotide, a guanylate cyclase C agonist clinically approved as a laxative, has recently been identified to exhibit renoprotective effects in a chronic kidney disease (CKD) model. This study evaluates the therapeutic effects of linaclotide on AKI triggered by I/R in a rat model with an initial comparison with other laxatives. Here, we show that linaclotide administration resulted in substantial reduction in serum creatinine levels, reflective of enhanced renal function. Histological examination revealed diminished tubular damage, and Sirius Red staining confirmed less collagen deposition, collectively indicating preserved structural integrity and mitigation of fibrosis. Further analysis demonstrated lowered expression of TGF-ß and associated fibrotic markers, α-SMA, MMP2, and TIMP1, implicating the downregulation of the fibrogenic TGF-ß pathway by linaclotide. Furthermore, one day after I/R insult, linaclotide profoundly diminished macrophage infiltration and suppressed critical pro-inflammatory cytokines such as TNF, IL-1ß, and IL-6, signifying its potential to disrupt initial inflammatory mechanisms integral to AKI pathology. These findings suggest that linaclotide, with its established safety profile, could extend its benefits beyond gastrointestinal issues and potentially serve as a therapeutic intervention for organ transplantation. Additionally, it could provide immediate and practical insights into selecting laxatives for managing patients with AKI or CKD, regardless of the cause, and for those receiving dialysis or transplant therapy.

Sulfamethoxazole-induced crystal nephropathy: characterization and prognosis in a case series.

Cotrimoxazole (Trimethoprim/Sulfamethoxazole-SMX) is frequently used in critically ill and immunocompromised patients. SMX is converted to N-acetyl-sulfamethoxazole (NASM) and excreted by the kidneys. NASM may form crystals in urine, especially in acid urine, that may induce a crystalline nephropathy. However, the imputability of crystals in acute kidney injury (AKI) has not been proven. We aimed to assess whether NASM crystals may promote AKI and to investigate risk factors associated with NASM crystalline nephropathy. Patients from Ile-de-France, France who developed AKI under SMX treatment introduced during hospitalization and had a crystalluria positive for NASM crystals were selected. Patients with excessive preanalytical delay for crystalluria or missing data regarding SMX treatment were excluded. We used the Naranjo score to assess the causal relationship between SMX and the development of AKI in patients with positive NASM crystalluria. Fourteen patients were included. SMX was the probable cause of AKI for 11 patients and a possible cause for 3 patients according to Naranjo score. Patients were exposed to high doses of SMX (but within recommended ranges), and most of them had a preexisting chronic kidney disease and were hypoalbuminemic. Urine pH was mildly acid (median 5.9). AKI occured more rapidly than expected after introduction of SMX (median 4 days) and recovered rapidly after drug discontinuation in most, but not all, cases. SMX is a probable cause of crystalline nephropathy. Monitoring of crystalluria in patients exposed to SMX may be of interest to prevent the development of crystalline nephropathy. Approval number of the study: BPD-2018-DIAG-008.

ROS-responsive curcumin-encapsulated nanoparticles for AKI therapy via promoting lipid degradation in renal tubules.

Lipid accumulation is a factor contributing to the pathogenesis of acute kidney injury (AKI), yet there are currently no approved pharmacotherapies aside from adjuvant therapy. A developed reactive oxygen species (ROS)-responsive drug delivery system (NPSBG@Cur) was developed to deliver the autophagy activator curcumin (Cur) in order to alleviate AKI by activating autophagy and promoting lipid droplet degradation. The nanoparticles were shown to be ROS-responsive in the H2O2 medium and demonstrate ROS-responsive uptake in palmitate (PA)-induced oxidative stress-damaged cells. NPSBG@Cur was found to effectively inhibit lipid accumulation by autophagosome transport in kidney tubular cells. Additionally, in a mouse AKI model, NPSBG@Cur was observed to significantly ameliorate renal damage by activating autophagy flux and improving lipid transport. These results suggest that the ROS-responsive drug delivery system augmented the therapeutic effect of Cur on AKI by improving lipid metabolism through autophagy activation. Therefore, targeting lipid metabolism with NPSBG@Cur may be a promising AKI treatment strategy.

A short treatment with resveratrol after a renal ischaemia-reperfusion injury prevents maladaptive repair and long-term chronic kidney disease in rats.

Acute kidney injury (AKI) often triggers physiological processes aimed at restoring renal function and architecture. However, this response can become maladaptive, leading to nephron loss and fibrosis. Although the therapeutic effects of resveratrol (RSV) are well established, its impact after AKI and for subsequent chronic kidney disease (CKD) remains unclear. This study assessed whether transient administration of RSV following ischaemia-reperfusion injury (IRI) could prevent the progression to CKD. Forty-one male Wistar rats were assigned randomly to sham surgery, bilateral renal ischaemia for 30 min (IR) or IR+RSV. The RSV treatment commenced 24 h after IRI and continued for 10 days. The rats were studied for either 10 days or 5 months, after which kidney function and structure were evaluated. Mitochondrial homeostasis, oxidant defence and renal inflammation state were also evaluated. Despite having the same severity of AKI, rats receiving RSV for 10 days after IRI exhibited significant improvement in kidney histological injury and reduced inflammation, although renal haemodynamic recovery was less pronounced. Resveratrol effectively prevented the elevation of tubular injury-related molecules and profibrotic signalling with reduced myofibroblast proliferation. Furthermore, RSV substantially improved the antioxidant response and mitochondrial homeostasis. After 5 months, RSV prevented the transition to CKD, as evidenced by the prevention of progressive proteinuria, renal dysfunction and tubulointerstitial fibrosis. This study demonstrates that a brief treatment with RSV following IRI is enough to prevent maladaptive repair and the development of CKD. Our findings highlight the importance of the early days of reperfusion, indicating that maladaptive responses can be reduced effectively following severe AKI. KEY POINTS: Physiological processes activated after acute kidney injury (AKI) can lead to maladaptive responses, causing nephron loss and fibrosis. Prophylactic renoprotection with resveratrol (RSV) has been described in experimental AKI, but its impact after AKI and for subsequent chronic kidney disease (CKD) remains unclear. In this study, we found that histological tubular injury persists 10 days after ischaemia-reperfusion injury and contributes to a failed repair phenotype in proximal tubular cells. Short-term RSV intervention influenced the post-ischaemic repair response and accelerated tubular recovery by reducing oxidative stress and mitochondrial damage. Furthermore, RSV targeted inflammation and profibrotic signalling during the maladaptive response, normalizing both processes. Resveratrol effectively prevented AKI-to-CKD transition even 5 months after the intervention. The study serves as a proof of concept, proposing RSV as a valuable candidate for further translational clinical studies to mitigate AKI-to-CKD transition.

Inhibition of both NOX and TNF-α exerts substantial renoprotective effects in renal ischemia reperfusion injury rat model.

BACKGROUND AND AIMS: Acute kidney injury (AKI) due to renal ischemia-reperfusion injury (RIRI) is associated with high morbidity and mortality, with no renoprotective drug available. Previous research focused on single drug targets, yet this approach has not reached translational success. Given the complexity of this condition, we aimed to identify a disease module and apply a multitarget network pharmacology approach. METHODS: Identification of a disease module with potential drug targets was performed utilizing Disease Module Detection algorithm using NADPH oxidases (NOXs) as seeds. We then assessed the protective effect of a multitarget network pharmacology targeting the identified module in a rat model of RIRI. Rats were divided into five groups; sham, RIRI, and RIRI treated with setanaxib (NOX inhibitor, 10 mg/kg), etanercept (TNF-α inhibitor, 10 mg/kg), and setanaxib and etanercept (5 mg/kg each). Kidney functions, histopathological changes and oxidative stress markers (MDA and reduced GSH) were assessed. Immunohistochemistry of inflammatory (TNF-α, NF-κB) apoptotic (cCasp-3, Bax/Bcl 2), fibrotic (α-SMA) and proteolysis (MMP-9) markers was performed. RESULTS: Our in-silico analysis yielded a disease module with TNF receptor 1 (TNFR1A) as the closest target to both NOX1 and NOX2. Targeting this module by a low-dose combination of setanaxib, and etanercept, resulted in a synergistic effect and ameliorated ischemic AKI in rats. This was evidenced by improved kidney function and reduced expression of inflammatory, apoptotic, proteolytic and fibrotic markers. CONCLUSIONS: Our findings show that applying a multitarget network pharmacology approach allows synergistic renoprotective effect in ischemic AKI and might pave the way towards translational success.

Removal of common antimicrobial agents by sustained low-efficiency dialysis.

Adequate dosing of antimicrobials is paramount for treating infections in critically ill patients undergoing kidney replacement therapy; however, little is known about antimicrobial removal by sustained low-efficiency dialysis (SLED). The objective was to quantify the removal of cefepime, daptomycin, meropenem, piperacillin-tazobactam, and vancomycin in patients undergoing SLED. Adult patients ≥18 years with acute kidney injury (AKI) or end-stage kidney disease receiving one of the select antimicrobials and requiring SLED were included. Blood and dialysate flow rates were maintained at 250 and 100 mL/min, respectively. Simultaneous arterial and venous blood samples for the analysis of antibiotic concentrations were collected hourly for 8 hours during SLED (on-SLED). Arterial samples were collected every 2 hours for up to 6 hours while not receiving SLED (off-SLED) for the calculation of SLED clearance, half-life (t1/2) on-SLED and off-SLED, and the fraction of removal by SLED (fD). Twenty-one patients completed the study: 52% male, mean age (±SD) 53 ± 13 years, and mean weight of 98 ± 30 kg. Eighty-six percent had AKI, and 4 patients were receiving cefepime, 3 daptomycin, 10 meropenem, 6 piperacillin-tazobactam, and 13 vancomycin. The average SLED time was 7.3 ± 1.1 hours, and the mean ultrafiltration rate was 95 ± 52 mL/hour (range 10-211). The t1/2 on-SLED was substantially lower than the off-SLED t1/2 for all antimicrobials, and the SLED fD varied between 44% and 77%. An 8-hour SLED session led to significant elimination of most antimicrobials evaluated. If SLED is performed, modification of the dosing regimen is warranted to avoid subtherapeutic concentrations.

Demotion of canonical/non-canonical inflammasome and pyroptosis alleviates ischemia/reperfusion-induced acute kidney injury: Novel role of the D2/D3 receptor agonist ropinirole.

Ropinirole used to treat Parkinson's disease highly targets the dopaminergic receptor D3 over the D2 receptor but although both are expressed in the kidneys the ropinirole potential to treat kidney injury provoked by ischemia/reperfusion (I/R) is undraped. We investigated whether ropinirole can alleviate renal I/R by studying its anti-inflammatory, antioxidant, and anti-pyroptotic effects targeting its aptitude to inhibit the High-mobility group box 1/Toll-like receptor 4/Nuclear factor-kappa B (HMGB1/TLR4/NF-κB) cue and the canonical/non-canonical NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome trajectories. Herein, bilateral I/R surgery was induced in animals to be either untreated or treated with ropinirole for three days after the insult. Ropinirole successfully improved the histopathological picture and renal function which was confirmed by reducing cystatin C and the standard parameters creatinine and blood urea nitrogen (BUN). Ropinirole achieved this through its anti-inflammatory capacity mediated by reducing the HMGB1/TLR4 axis and inactivating NF-κB, which are upstream regulators of the NLRP3 pathway. As a result, the injurious inflammasome markers (NLRP3, apoptosis-associated speck-like protein (ASC), active caspase-1) and their target cytokines interleukin-1 beta (IL-1ß) and IL-18 were decreased. Ropinirole also reduced the pyroptotic cell death markers caspase-11 and gasdermin-D. Furthermore, ropinirole by replenishing antioxidants and decreasing malondialdehyde helped to reduce oxidative stress in the kidneys. The docking findings confirmed that ropinirole highly binds to the dopaminergic D3 receptor more than to the D2 receptor. In conclusion, ropinirole has the potential to be a reno-therapeutic treatment against I/R insult by abating the inflammatory NLRP3 inflammasome signal, pyroptosis, and oxidative stress.

Recent Advances in Nanomaterials for the Treatment of Acute Kidney Injury.

Acute kidney injury (AKI) is a serious clinical syndrome with high morbidity, elevated mortality, and poor prognosis, commonly considered a "sword of Damocles" for hospitalized patients, especially those in intensive care units. Oxidative stress, inflammation, and apoptosis, caused by the excessive production of reactive oxygen species (ROS), play a key role in AKI progression. Hence, the investigation of effective and safe antioxidants and inflammatory regulators to scavenge overexpressed ROS and regulate excessive inflammation has become a promising therapeutic option. However, the unique physiological structure and complex pathological alterations in the kidneys render traditional therapies ineffective, impeding the residence and efficacy of most antioxidant and anti-inflammatory small molecule drugs within the renal milieu. Recently, nanotherapeutic interventions have emerged as a promising and prospective strategy for AKI, overcoming traditional treatment dilemmas through alterations in size, shape, charge, and surface modifications. This Review succinctly summarizes the latest advancements in nanotherapeutic approaches for AKI, encompassing nanozymes, ROS scavenger nanomaterials, MSC-EVs, and nanomaterials loaded with antioxidants and inflammatory regulator. Following this, strategies aimed at enhancing biocompatibility and kidney targeting are introduced. Furthermore, a brief discussion on the current challenges and future prospects in this research field is presented, providing a comprehensive overview of the evolving landscape of nanotherapeutic interventions for AKI.

Intervention treatment reducing cellular senescence inhibits tubulointerstitial fibrosis in diabetic mice following acute kidney injury.

Senescence of kidney tubules leads to tubulointerstitial fibrosis (TIF). Proximal tubular epithelial cells undergo stress-induced senescence during diabetes and episodes of acute kidney injury (AKI), and combining these injuries promotes the progression of diabetic kidney disease (DKD). Since TIF is crucial to progression of DKD, we examined the therapeutic potential of targeting senescence with a senolytic drug (HSP90 inhibitor) and/or a senostatic drug (ASK1 inhibitor) in a model of TIF in which AKI is superimposed on diabetes. After 8 weeks of streptozotocin-induced diabetes, mice underwent bilateral clamping of renal pedicles to induce mild AKI, followed by 28 days of reperfusion. Groups of mice (n=10-12) received either vehicle, HSP90 inhibitor (alvespimycin), ASK1 inhibitor (GS-444217), or both treatments. Vehicle-treated mice displayed tubular injury at day 3 and extensive tubular cell senescence at day 10, which remained unresolved at day 28. Markers of senescence (Cdkn1a and Cdkn2a), inflammation (Cd68, Tnf, and Ccl2), and TIF (Col1a1, Col4a3, α-Sma/Acta2, and Tgfb1) were elevated at day 28, coinciding with renal function impairment. Treatment with alvespimycin alone reduced kidney senescence and levels of Col1a1, Acta2, Tgfb1, and Cd68; however, further treatment with GS-444217 also reduced Col4a3, Tnf, Ccl2, and renal function impairment. Senolytic therapy can inhibit TIF during DKD, but its effectiveness can be improved by follow-up treatment with a senostatic inhibitor, which has important implications for treating progressive DKD.

Reactive oxygen/nitrogen species scavenging and inflammatory regulation by renal-targeted bio-inspired rhodium nanozymes for acute kidney injury theranostics.

Acute kidney injury (AKI) results from the rapid deterioration of renal function, which is mainly treated by transplantation and dialysis, and has a high mortality rate. Inflammation induced by excess reactive oxygen/nitrogen species (RONS) plays a crucial role in AKI. Although small molecule antioxidants have been utilized to alleviate AKI, low bioavailability and side-effect of these drugs tremendously limit their clinical use. Hence, we successfully construct ultra-small (2-4 nm) rhodium nanoparticles modified with l-serine (denoted as Rh-Ser). Our results show that Rh-Ser with multiple enzyme-mimicking activities, allows remove various RONS to protect damaged kidney cells. Additionally, the ultrasmall size of Rh-Ser is conducive to enrichment in the renal tubules, and the modification of l-serine enables Rh-Ser to bind to kidney injury molecule-1, which is highly expressed on the surface of damaged renal cells, thereby targeting the damaged kidney and increasing the retention time. Moreover, Rh-Ser allows the production of oxygen at the inflammatory site, thus further improving hypoxia and inhibiting pro-inflammatory macrophages to relieve inflammation, and increasing the survival rate of AKI mice from 0 to 80%, which exhibits a better therapeutic effect than that of small molecule drug. Photoacoustic and fluorescence imaging can effectively monitor and evaluate the enrichment and therapeutic effect of Rh-Ser. Our study provides a promising strategy for the targeted treatment of AKI via RONS scavenging and inflammatory regulation.