Rat Kidney Research Articles

Investigating the attenuating effects of metformin-loaded selenium nanoparticles coupled with Myrtus communis L. flower extract on CaOx deposition in male Sprague Dawley rat kidneys via regulating MAPK signaling pathway

Kidney stones are a foremost clinical concern in urology with CaOx crystals accounting for roughly 80% of these renal formations. This research endeavor seeks to ascertain the protective effects of Metformin-encapsulated selenium nanoparticles (M@Se NPs), combined with a 55% hydroethanolic flower extract from Myrtus communis L. (MCL) in countering the formation of kidney stones in Male Sprague Dawley rats. The particle's diameter was measured to be 39 nm and 13.8 nm from DLS and HR-TEM analysis. Rat groups administered with the MCL-M@Se NPs (1:1.5:1) exhibited reduced renal stone formation in urine and serum analysis compared to the negative control group. Histological evaluations of kidney samples using H&E, and MTS staining indicated a subdued presence of ECM deposition in contrast to other rat groups. Conclusively, the protective mechanism of MCL-M@Se NPs against CaOx stone damage can be confidently attributed to the obstruction of the MAPK signaling pathway.

Evaluation of subchronic toxicity of diabetna capsules in experimental animals

This research aimed to evaluate the subchronic toxicity of Diabetna capsules through oral administration in experimental animals. The subchronic toxicity was studied in Wistar rats with oral doses of 0.72 g/kg/day (equal to recommended human dose) and 2.16 g/kg/day (3 times as high as recommended human dose) in consecutive 12 weeks, following guidance from the World Health Organization and Organisation for Economic Co-operation and Development. Our result showed that Diabetna capsules had no deleterious effect on hematological parameters, hepato-renal functions, macroscopic and microscopic images of the livers and kidneys of Wistar rats. In conclusion, Diabetna capsules did not produce subchronic toxicity in experimental animals.

Ameliorative Effect of Pigeon Pea Leaves and Ginger Extract on Oxidative Stress Condition in Kidney and Liver of Experimental Diabetic Rats

Ameliorative Effect of Pigeon Pea Leaves and Ginger Extract on Oxidative Stress Condition in Kidney and Liver of Experimental Diabetic Rats

Interaction of Angiotensin-(1−7) with kinins in the kidney circulation: Role of B1 receptors

Changes in renal hemodynamics impact renal function during physiological and pathological conditions. In this context, renal vascular resistance (RVR) is regulated by components of the Renin-Angiotensin System (RAS) and the Kallikrein-Kinin System (KKS). However, the interaction between these vasoactive peptides on RVR is still poorly understood. Here, we studied the crosstalk between angiotensin-(1−7) and kinins on RVR. The right kidneys of Wistar rats were isolated and perfused in a closed-circuit system. The perfusion pressure and renal perfusate flow were continuously monitored. Ang-(1−7) (1.0–25.0 nM) caused a sustained, dose-dependent reduction of relative RVR (rRVR). This phenomenon was sensitive to 10 nM A-779, a specific Mas receptor (MasR) antagonist. Bradykinin (BK) promoted a sustained and transient reduction in rRVR at 1.25 nM and 125 nM, respectively. The transient effect was abolished by 4 μM des-Arg9-Leu8-bradykinin (DALBK), a specific kinin B1 receptor (B1R) antagonist. Accordingly, des-Arg9-bradykinin (DABK) 1 μM (a B1R agonist) increased rRVR. Interestingly, pre-perfusion of Ang-(1−7) changed the sustained reduction of rRVR triggered by 1.25 nM BK into a transient effect. On the other hand, pre-perfusion of Ang-(1−7) primed and potentiated the DABK response, this mechanism being sensitive to A-779 and DALBK. Binding studies performed with CHO cells stably transfected with MasR, B1R, and kinin B2 receptor (B2R) showed no direct interaction between Ang-(1−7) with B1R or B2R. In conclusion, our findings suggest that Ang-(1−7) differentially modulates kinin's effect on RVR in isolated rat kidneys. These results help to expand the current knowledge regarding the crosstalk between the RAS and KKS complex network in RVR.

Transcriptomics-based exploration of shared M1-type macrophage-related biomarker in acute kidney injury after kidney transplantation and acute rejection after kidney transplantation

BackgroundMacrophage type 1 (M1) cells are associated with both acute kidney injury (AKI) during kidney transplantation and acute rejection (AR) after kidney transplantation. Our study explored M1-related biomarkers involved in both AKI and AR and their potential biological functions. MethodsBased on the Gene Expression Omnibus (GEO) database, the immune cell infiltration levels and differentially expressed genes were examined in AKI and AR in the kidney transplantation; M1-related genes shared in AKI and AR were identified using weighted gene co-expression analysis (WGCNA) system. Subsequently, protein-protein interaction (PPI) networks and machine learning methods to identify Hub genes and construct diagnostic models. Both AKI model and AR rat models were built to validate the expressions of Hub genes and test the injury phenotype, oxidative stress markers, and inflammatory factors. Finally, the transcription factor (TF)-Hub gene and micro-RNA (miRNA)-Hub gene regulatory networks were constructed based on identified Hub genes. ResultsOut of 2167 differential expression genes (DEGs) in AKI and 2100 DEGs in AR, four M1-related Hub genes were obtained by PPI networks and machine learning methods, namely GBP2, TYROBP, CCR5, and TLR8. The calibration curves in the nomogram diagnostic model for these four Hub genes suggested the same predictive probability as an ideal model for AKI and AR after kidney transplantation (AUC values of the area under the ROC curve were all >0.7). The same observations were confirmed in ischemia reperfusion injury (IRI) and AR rat models by identifying common four Hub genes (GBP2, TYROBP, TLR8, and CCR5). Western blots showed that these four Hub genes were significantly different in rat models of IRI and AR (all p<0.05). Compared with the control group, IRI and AR groups showed aggravated histopathological damage and increased secretion of oxidative stress markers and inflammatory factors in rat kidneys (all p<0.05). Finally, TF-Hub and miRNA-Hub gene regulatory networks were constructed to provide a theoretical basis for the regulation of Hub genes. ConclusionWe identified four macrophage M1-related Hub genes shared among AKI and AR after kidney transplantation. These genes may be considered for diagnosis of AKI and AR after kidney transplantation.

Changes in Histological Features, Apoptosis and Necroptosis, and Inflammatory Status in the Livers and Kidneys of Young and Adult Rats

Changes in Histological Features, Apoptosis and Necroptosis, and Inflammatory Status in the Livers and Kidneys of Young and Adult Rats

Methanolic leaf extract of Vernonia amygdalina mitigates cadmium-induced oxidative stress in the liver and kidney of adult male Wistar rats

ABSTRACT Cadmium is a hazardous metal swiftly generated through industrialization and persists in the environment due to its non-biodegradability. Cadmium induces liver and kidney damage primarily by triggering free radical production causing oxidative stress. This study explored the potential of methanolic extract of Vernonia amygdalina in ameliorating cadmium-induced oxidative stress. Twenty adult male Wistar rats were used for this experiment, with each group consisting of five rats. The first group was the unexposed control group given standard rat chow and distilled water ad libitum while the test groups (II-IV) were orally administered with cadmium at standard doses of 12 mg/kg/BW. Vernonia amygdalina at standard doses of 100 mg/kg/BW and 200 mg/kg/BW was administered to rats in groups III and IV respectively. After 28 days, the rats were euthanized using cervical dislocation and the livers and kidneys were analyzed for histological and mRNA analysis of tumor necrosis factor-alpha (TNF-α) and interleukin-10 (IL-10). The results showed significant pathological changes in the histoarchitecture of the livers and kidneys, indicating oxidative stress and the effectiveness of Vernonia amygdalina, which mitigated cadmium-induced oxidative damage by modulating TNF-α and IL-10 expression and ameliorating the histological alteration seen in the studied organs.

Preclinical Evaluation and Pilot Clinical Study of 18F-Labeled Inhibitor Peptide for Noninvasive Positron Emission Tomography Mapping of Angiotensin Converting Enzyme 2.

Angiotensin-converting enzyme 2 (ACE2) is the main molecular target for coronavirus SARS-CoV-2 to enter cells. Molecularly specific tracers that bind to ACE2 with high affinity can be used to determine the tissue distribution of this important receptor, noninvasively. A novel targeting PET imaging probe, [18F]AlF-DX600-BCH, was developed to detect the in vivo expression of ACE2 and monitor response to therapy. Preclinical experiments, including biodistribution, PET imaging, and tissue section analysis, were conducted after tests of in vitro and in vivo stability and pharmacokinetics. The agent was advanced to clinical evaluation in 10 volunteers who received [18F]AlF-DX600-BCH PET/CT at 1 and 2 h after injection (NCT04542863). Preclinical results of both biodistribution and PET demonstrated [18F]AlF-DX600-BCH accumulation in rat kidney (standardized uptake value; SUVkidney/normal > 50), along with specific uptake in testes (SUVtestis/normal > 10) tissues. Kidney, gastrointestinal, and bronchial cell labeling were correlated to ACE2 positive by immunohistochemistry (IHC) staining. In clinical imaging, significant tracer accumulation was predominantly observed in the urinary and reproductive system (SUVrenalcortex = 32.00, SUVtestis = 4.56), and the conjunctiva and nasal mucosa saw elevated uptake in several cases. This work is the first report of a radioisotope probe, [18F]AlF-DX600-BCH, targeting ACE2 with promising preliminary preclinical and translational outlook, thereby demonstrating the potential of noninvasive mapping of ACE2.

#1437 Renal expression pattern of the relaxin receptor, RXFP1, and effects of the RXFP1 agonist, AZD5462, on renin in non-human primates and humans

Abstract Background and Aims RXFP1 is a G protein-coupled receptor (GPCR) for the pregnancy hormone, relaxin. While preclinical studies, performed primarily in rodent, describe beneficial effects of this pleiotropic peptide across several organ systems, there has been a disappointing lack of success in translating these observations into clinical benefit. To provide a potential pharmacological explanation accounting for this translational gap, the aim of this study was thus to thoroughly evaluate RXFP1 expression across species and tissues as well as to evaluate the renal-intrinsic effects of the RXFP1 agonist, AZD5462. Method Unbiased bioinformatic analysis of several gene expression databases was used as a first approach to compare RXFP1 tissue-level expression between rodent and human. Experimental validation was subsequently performed using scRNAseq, RNAscope and immunohistochemistry on mouse, rat, non-human primate (NHP) and human kidney. The putative renal target engagement effects of RXFP1 agonism were assessed by determining the acute and chronic effects of the RXFP1-selective small molecule agonist, AZD5462, on plasma renin concentrations in both NHPs and in a Phase 1 randomized, single-blind, placebo-controlled study in healthy humans. Results RXFP1 was identified as one of the most highly expressed GPCRs in human and NHP kidney glomeruli. Specifically, by multiple assays, we identified glomerular endothelial cells as the principal cell type expressing RXFP1. This observation is in stark contrast to mouse and rat kidney, where RXFP1 was not readily detected. AZD5462 administered orally to NHPs and healthy human participants elicited an early and sustained dose-dependent increase in plasma renin concentration, and in humans an additional decline in serum creatinine. Conclusion Human RXFP1 kidney glomerular expression is conserved with NHPs but not rodent, thus highlighting the translational and pharmacological challenges in studying RXFP1/relaxin biology across species. The concordant ability of AZD5462 to induce elevations in renin and reduction in serum creatinine, together with relaxin's reported renal-hemodynamic activity in humans, may underlie a previously unappreciated renal-intrinsic RXFP1 target engagement mechanism driving its hemodynamic and renal effects. The potential therapeutic benefits of RXFP1 agonism are the subject of on-going clinical trials in heart failure patients.

Lycopene in Combination with Insulin Triggers Antioxidant Defenses and Increases the Expression of Components That Detoxify Advanced Glycation Products in Kidneys of Diabetic Rats.

Biochemical events provoked by oxidative stress and advanced glycation may be inhibited by combining natural bioactives with classic therapeutic agents, which arise as strategies to mitigate diabetic complications. The aim of this study was to investigate whether lycopene combined with a reduced insulin dose is able to control glycemia and to oppose glycoxidative stress in kidneys of diabetic rats. Streptozotocin-induced diabetic rats were treated with 45 mg/kg lycopene + 1 U/day insulin for 30 days. The study assessed glycemia, insulin sensitivity, lipid profile and paraoxonase 1 (PON-1) activity in plasma. Superoxide dismutase (SOD) and catalase (CAT) activities and the protein levels of advanced glycation end-product receptor 1 (AGE-R1) and glyoxalase-1 (GLO-1) in the kidneys were also investigated. An effective glycemic control was achieved with lycopene plus insulin, which may be attributed to improvements in insulin sensitivity. The combined therapy decreased the dyslipidemia and increased the PON-1 activity. In the kidneys, lycopene plus insulin increased the activities of SOD and CAT and the levels of AGE-R1 and GLO-1, which may be contributing to the antialbuminuric effect. These findings demonstrate that lycopene may aggregate favorable effects to insulin against diabetic complications resulting from glycoxidative stress.

#694 Effects of nonsteroidal mineralocorticoid receptor antagonists on kidney of cirrhotic rats

Abstract Background and Aims Aldosterone binds to renal mineralocorticoid receptors (MRs) to regulate fluid and electrolytes homeostasis. In addition, aldosterone can be deleterious as a driver of inflammation and tissue fibrosis in several organs. Thus, blockade of aldosterone represents an important option to mitigate the target-organ damage. Mineralocorticoid receptor antagonists (MRAs) have been widely used as diuretic drugs for the management of hypertension, cirrhosis, and heart failure. However, the use of MRAs is limited by adverse events such as hyperkalemia. More recently, novel nonsteroidal selective MRAs with improved safety profiles have been developed. This nonsteroidal MRA (finerenone) has higher selectivity and stronger affinity for the MR, leading to lower risk of hyperkalemia. Recent evidences showed that finerenone reduces albuminuria, risk of CKD progression, and cardiovascular events in patients with chronic kidney disease and type 2 diabetes with a low incidence of hyperkalemia related treatment discontinuation. The pathophysiology of cirrhosis is very similar to that of cardiac failure. Decompensated cirrhosis is frequently treated with the MRAs. In addition to fluid management, MRAs showed hepatoprotective actions via reducing oxidative stress and inflammatory responses in CCl4-induced and common bile duct ligation (CBDL)-induced liver injury models. The potential beneficial effects of nonsteroidal MRA on cirrhosis had never been studied. This study aims to explore the renal protective role of nonsteroidal selective MRA and associated mechanisms in common bile duct ligation-related liver injury in rat model. Method CBDL was used to create liver injury in the Male Sprague-Dawley Drats. Finerenone (10 mg/kg/day) or vehicle was administered since the 1st day after CBDL. The effects of nonsteroidal selective MRA on kidneys were surveyed in two paralleled series on the 7th day (inflammation) and the 28th day (cirrhosis), respectively. The following parameters were evaluated: (a) hemodynamic parameters; (b) serum potassium, liver and renal function; (c) in-situ kidney perfusion; (d) western analyses of renal cortex and medulla. Results Compared with the vehicle-treated group, there was significantly lower renal vascular responsiveness to ET-1 in CBDL rats receiving 28 days of MRA (p&amp;lt;0.05) (Fig. 1B), but not in those receiving 7 days of MRA (Fig. 1A). MRA treatment led to no significant change in mean arterial pressure, portal pressure, serum potassium, liver, and renal function in CBDL rats (Table 1). The expressions of vasoactive mediators, such as iNOS, eNOS, ETA, and ETB in both renal cortex and medulla showed no significant change in CBDL rats following 28 days of MRA treatment (Fig. 2). Conclusion MRA treatment led to no significant effects on hemodynamics, liver, and renal function, but lower renal vascular responsiveness to ET-1 in CBDL rats receiving 28 days of MRA. The exact mechanisms remained to be further studied.

Effects of organophosphates on precision-cut kidney slices

Organophosphate (OP) poisoning, both accidental and with suicidal intent, is a global medical challenge. While the primary toxicity of these pesticides is based on the inhibition of acetylcholinesterase (AChE), case reports describe patients developing OP-mediated renal insufficiency. We set out to investigate possible pathomechanisms utilizing rat precision-cut kidney slices (PCKS). Depending on the method of investigation, PCKS were observed for a maximum of 10 days. PCKS exposed to OP compounds (malaoxon, malathion, paraoxon, parathion) showed a dose-dependent loss of viability and a reduction of total protein content over the course of 10 days. A concentration of 500 µM OP showed the most differences between OP compounds. After two days of incubation parathion showed a significantly lower level of viability than malathion. The respective effects of paraoxon and malaoxon were not significantly different from the control. However, effects of OP were only observed in concentrations exceeding those that were needed to achieve significant AChE inhibition in rat kidney tissue. In addition, we observed histological changes, without inducing LDH leakage. Overall, results suggest that OP exert effects in kidney tissue, that exceed those expected from the sole inhibition of AChE and vary between compounds. Without signs of necrosis, findings call for studies that address other possible pathomechanisms, including inflammatory response, oxidative stress or activation of apoptosis to further understand the nephrotoxicity of OP compounds. Monitoring oxon concentration over time, we demonstrated reduced enzyme-inhibiting properties in the presence of PCKS, suggesting interactions between OP compound and kidney tissue.

#1331 PCSK9 inhibitor addition during hypothermic perfusion protects kidney from ischemic damage in a rat model of donation after circulatory death

Abstract Background and Aims PCSK9 inhibitors (PCSK9i) are a new class of cholesterol-lowering drugs that is gaining market share in treating hypercholesterolemia because of their effectiveness in lowering LDL cholesterol and cardiovascular risk, even in patients with kidney disease. In addition to the well-known effect of inhibiting the LDL receptor catabolism, new pharmacological properties are being discovered. Experimental cellular and animal models have showed that PCSK9i reduce apoptosis, pyroptosis and in acute myocardial infarction decrease the infarct area, suggesting their protective role in tissue ischemia. However, so far PCSK9i effect on renal ischemic damage has not yet been studied. The aim of this study was to evaluate the effects of PEP 2-8 (PCSK9i) addition during hypothermic perfusion (HP) on ischemic kidney damage (ID) in a rat model of donation after circulatory death (DCD). Method n. 15 Sprague-Dawley rats were used as DCD donors. Briefly after a midline laparotomy, the left and right retroperitoneal renal areas were exposed, and lumbar arteries were isolated and sectioned; subsequently, the renal arteries and veins were isolated. After 30 min of warm ischemia, induced by aorta clamping, left and right nephrectomies were completed with preservation of the renal hilums. Then the kidneys were perfused with Perf-Gen Solution (100 ml) (Institut Georges Lopez, Lissieu, France) or Perf-Gen solution (100 ml) supplemented with 3ug (10ug/kg) of PEP 2-8. Continuous HP was performed for 6 h at 4 °C. DCD right and left kidneys of each rat were randomized to the following experimental groups: CTRL group: n = 15 DCD rat kidneys perfused with Perf-Gen PEP group: n = 15 DCD rat kidneys perfused with Pef-Gen supplemented with PEP 2-8. Effluent fluid was collected at the beginning (T0) and at the end (T6h) of HP. Glucose and potassium levels were measured in the effluent fluid at T0 and T6h. At T6h the kidneys were splitted into three aliquots; one was fixed in 10% formalin for morphological studies, and the other two were stored in trizol for gene expression studies and at −80 °C for biochemical assays respectively. Tubular ischemic damage (TID) was evaluated at T6 by scoring all tubules observed in at least 10 non-consecutive high-powered fields, as described by Paller (Paller Score). NOX- 4 gene expression was studied by RT-PCR assay. Tissue LDH and ATP levels were measured at T6h. Results PEP 2-8 treated kidneys showed a lower TID score compared to CTRL (PEP 107.0 IQR 90.75-116.0 vs CTRL 134.5 IQR 131.3-155.3 p &amp;lt; 0.005) (Fig. 1). The percentage of tubules with score zero (normal tubules) was higher in PEP than CTRL (PEP 29.0% range % 24.2-39.5 vs CTRL 9.5% range % 5.5-12.0, p &amp;lt; 0.001). The percentage of tubules with necrosis was lower in PEP than CTRL (PEP 5.5% range % 3.2-10.5 vs CTRL 12.5% range % 9.0-15.7, p &amp;lt; 0.005). Expression of NOX-4 gene, known inducer of apoptosis, was lower in PEP compared to CTRL (p &amp;lt; 0.05) Tissue ATP content was higher in PEP than CTRL (PEP 0.031 ± 0.01 vs CTRL 0.025 ± 0.006 p &amp;lt; 0.05). In tissue samples at T6 LDH was lower in PEP than CTRL (PEP 554.8 ± 164.7 vs CTRL 742.4 ± 256.7 p &amp;lt; 0.05) conversely the potassium release in effluent was significant only in CTRL (T6 vs T0 p &amp;lt; 0.01), according to TID score results. During HP, PEP 2-8 treated kidneys released more glucose in the effluent than CTRL kidneys (PEP 35.4 IQR 12.3-82.9 vs CTRL 12.3 IQR 7.1-70.5 p &amp;lt; 0.01). Conclusion Our preliminary results show that PEP 2-8 added to Perf-Gen solution during HP protects kidneys from ID, preserving energy metabolism in rat DCD model. To the best of our knowledge, this is the first evidence of protective role of PCSK9 inhibition in pre-transplant renal conditioning and potentially it could be used in conditioning other organs (liver, lung). However, further studies are necessary to understand the mechanisms underlying PCSK9i effect on energy metabolism and neoglucogenesis.

#1446 PCSK9 inhibitor addition during hypothermic perfusion protects kidney from ischemic damage in a rat model of donation after circulatory death

Abstract Background and Aims PCSK9 inhibitors (PCSK9i) are a new class of cholesterol-lowering drugs that is gaining market share in treating hypercholesterolemia because of their effectiveness in lowering LDL cholesterol and cardiovascular risk, even in patients with kidney disease. In addition to the well-known effect of inhibiting the LDL receptor catabolism, new pharmacological properties are being discovered. Experimental cellular and animal models have showed that PCSK9i reduce apoptosis, pyroptosis and in acute myocardial infarction decrease the infarct area, suggesting their protective role in tissue ischemia. However, so far PCSK9i effect on renal ischemic damage has not yet been studied. The aim of this study was to evaluate the effects of PEP 2-8(PCSK9i) addition during hypothermic perfusion (HP) on ischemic kidney damage (ID) in a rat model of donation after circulatory death (DCD). Method n. 15 Sprague-Dawley rats were used as DCD donors. Briefly after a midline laparotomy, the left and right retroperitoneal renal areas were exposed, and lumbar arteries were isolated and sectioned; subsequently, the renal arteries and veins were isolated. After 30 min of warm ischemia, induced by aorta clamping, left and right nephrectomies were completed with preservation of the renal hilums. Then the kidneys were perfused with Perf-Gen Solution (100 ml) (Institut Georges Lopez, Lissieu, France) or Perf-Gen solution (100 ml) supplemented with 3ug (10ug/kg) of PEP 2-8. Continuous HP was performed for 6 h at 4 °C. DCD right and left kidneys of each rat were randomized to the following experimental groups: CTRL group: n = 15 DCD rat kidneys perfused with Perf-Gen PEP group: n = 15 DCD rat kidneys perfused with Pef-Gen supplemented with PEP 2-8. Effluent fluid was collected at the beginning (T0) and at the end (T6h) of HP. Glucose and potassium levels were measured in the effluent fluid at T0 and T6h. At T6h the kidneys were splitted into three aliquots; one was fixed in 10% formalin for morphological studies, and the other two were stored in trizol for gene expression studies and at −80 °C for biochemical assays respectively. Tubular ischemic damage (TID) was evaluated at T6 by scoring all tubules observed in at least 10 non-consecutive high-powered fields, as described by Paller (Paller Score). NOX- 4 gene expression was studied by RT-PCR assay. Tissue LDH and ATP levels were measured at T6h. Results PEP 2-8 treated kidneys showed a lower TID score compared to CTRL (PEP 107.0 IQR 90.75-116.0 vs CTRL 134.5 IQR 131.3-155.3 p &amp;lt; 0.005) (Fig. 1). The percentage of tubules with score zero (normal tubules) was higher in PEP than CTRL (PEP 29.0% range % 24.2-39.5 vs CTRL 9.5% range % 5.5-12.0, p &amp;lt; 0.001). The percentage of tubules with necrosis was lower in PEP than CTRL (PEP 5.5% range % 3.2-10.5 vs CTRL 12.5% range % 9.0-15.7, p &amp;lt; 0.005). Expression of NOX-4 gene, known inducer of apoptosis, was lower in PEP compared to CTRL (p &amp;lt; 0.05) Tissue ATP content was higher in PEP than CTRL (PEP 0.031 ± 0.01 vs CTRL 0.025 ± 0.006 p &amp;lt; 0.05). In tissue samples at T6 LDH was lower in PEP than CTRL (PEP 554.8 ± 164.7 vs CTRL 742.4 ± 256.7 p &amp;lt; 0.05) conversely the potassium release in effluent was significant only in CTRL (T6 vs T0 p &amp;lt; 0.01), according to TID score results. During HP, PEP 2-8 treated kidneys released more glucose in the effluent than CTRL kidneys (PEP 35.4 IQR 12.3-82.9 vs CTRL 12.3 IQR 7.1-70.5 p &amp;lt; 0.01). Conclusion Our preliminary results show that PEP 2-8 added to Perf-Gen solution during HP protects kidneys from ID, preserving energy metabolism in rat DCD model. To the best of our knowledge, this is the first evidence of protective role of PCSK9 inhibition in pre-transplant renal conditioning and potentially it could be used in conditioning other organs (liver, lung). However, further studies are necessary to understand the mechanisms underlying PCSK9i effect on energy metabolism and neoglucogenesis.

High Dose Sesbania Grandiflora Extract Alters Rat Kidney Electrolytes based on Insights from Indonesia

This study investigates the acute toxicity of white turi flower extract (Sesbania grandiflora) on kidney electrolyte levels in rats (Rattus norvegicus). Conducted at Muhammadiyah University of Sidoarjo, male Wistar rats were divided into control and treatment groups, receiving 10,000, 15,000, and 20,000 mg/kgBW doses. Symptoms of toxicity included lethargy and hair loss, but no deaths occurred. Despite normal macroscopic kidney observations, sodium and potassium levels significantly increased with higher doses (p=0.000). These findings suggest that high doses of white turi flower extract can affect kidney electrolytes, indicating potential toxicity. Further research is needed to assess long-term safety for medicinal use. Highlights: 1. High doses increase sodium and potassium in rat kidneys.2. Symptoms: lethargy, hair loss, no fatalities.3. Requires further research for long-term safety. Keywords: Sesbania grandiflora, acute toxicity, kidney electrolytes, sodium, potassium

Protective effects of nodosin against lipopolysaccharide-induced acute kidney injury through regulation of oxidative stress, inflammation, and ferroptosis in rats.

This research aimed to explore the impact of nodosin on lipopolysaccharide (LPS)-induced acute kidney injury (AKI) in rats. The study involved administering nodosin orally at doses of 2 and 4mg/kg body weight orally to rats for 7 days before induction of AKI. Toward the end of the study, urine, blood, and kidneys were gathered from the rats to undergo biochemical and molecular examination after sacrificing them. Serum Scr, BUN, urine NGAL, and KIM-1 levels were significantly decreased in nodosin-treated AKI rats. Besides, nodosin administration resulted in a significant reduction in kidney MDA and 4-HNE levels. In contrast, antioxidant enzymes such as SOD, CAT, GPx, and GST levels increased, as well as Nrf2, NQO1, and HO-1 levels increased, while Keap-1 mRNA levels decreased in AKI rats. In addition, AKI rats treated with nodosin reversed excessive ferroptosis in the kidneys of LPS-induced AKI rats, as evidenced by increased mRNA and protein levels of GPX4, SLC7A11, and FTH-1. The administration of nodosin significantly reduced levels of inflammatory markers including TLR4, MYD88, NF-κB p65, IkKβ, and IL-1β, while IL-10 levels increased in the AKI-induced rats. Besides, histopathological changes were reduced in AKI-induced rats treated with nodosin. Nodosin proves highly beneficial in safeguarding the kidney from AKI by regulating oxidative stress, inflammation, and ferroptosis. The treatment of AKI could greatly benefit from this option.

Elucidating the mechanism of action of Radix Angelica sinensis (Oliv.) Diels and Radix Astragalus mongholicus Bunge ultrafiltration extract on radiation-induced myocardial fibrosis based on network pharmacology and experimental research

Myocardial fibrosis can induce cardiac dysfunction and remodeling. Great attention has been paid to traditional chinese medicine (TCM) 's effectiveness in treating MF. Radix Angelica sinensis (Oliv.) Diels and Radix Astragalus mongholicus Bunge ultrafiltration extract (RAS-RA), which is a key TCM compound preparation, have high efficacy in regulating inflammation. However, studies on its therapeutic effect on radiation-induced myocardial fibrosis (RIMF) are rare. In this study, RAS-RA had therapeutic efficacy in RIMF and elucidated its mechanism of action. First, we formulated the prediction network that described the relation of RAS-RA with RIMF according to data obtained in different databases. Then, we conducted functional enrichment to investigate the functions and pathways associated with potential RIMF targets for RAS-RA. In vivo experiments were also performed to verify these functions and pathways. Second, small animal ultrasound examinations, H&E staining, Masson staining, transmission electron microscopy, Enzyme-linked immunosorbent assay (ELISA), Western-blotting, Immunohistochemical method and biochemical assays were conducted to investigate the possible key anti-RIMF pathway in RAS-RA. In total, 440 targets were detected in those 21 effective components of RAS-RA; meanwhile, 1,646 RIMF-related disease targets were also discovered. After that, PPI network analysis was conducted to identify 20 key targets based on 215 overlap gene targets. As indicated by the gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analysis results, inflammation and PI3K/AKT/mTOR pathways might have important effects on the therapeutic effects on RIMF. Molecular docking analysis revealed high binding of effective components to targets (affinity < −6 kcal/mol). Based on experimental verification results, RAS-RA greatly mitigated myocardial fibrosis while recovering the cardiac activity of rats caused by X-rays. According to relevant protein expression profiles, the PI3K/AKT/mTOR pathway was important for anti-fibrosis effect of RAS-RA. Experimental studies showed that RAS-RA improved cardiac function, decreased pathological damage and collagen fiber deposition in cardiac tissues, and improved the mitochondrial structure of the heart of rats. RAS-RA also downregulated TNF-α, IL-6, and IL-1β levels. Additionally, RAS-RA improved the liver and kidney functions and pathological injury of rat kidney and liver tissues, enhanced liver and kidney functions, and protected the liver and kidneys. RAS-RA also increased PI3K, AKT and mTOR protein levels within cardiac tissues and downregulated α-SMA, Collagen I, and Collagen III. The findings of this study suggested that RAS-RA decreased RIMF by suppressing collagen deposition and inflammatory response by inhibiting the PI3K/AKT/mTOR pathway. Thus, RAS-RA was the potential therapeutic agent used to alleviate RIMF.

A pharmacokinetic model for hyperpolarized 13C-pyruvate MRI when using metabolite-specific bSSFP sequences.

Metabolite-specific balanced SSFP (MS-bSSFP) sequences are increasingly used in hyperpolarized [1-13C]Pyruvate (HP 13C) MRI studies as they improve SNR by refocusing the magnetization each TR. Currently, pharmacokinetic models used to fit conversion rate constants, kPL and kPB, and rate constant maps do not account for differences in the signal evolution of MS-bSSFP acquisitions. In this work, a flexible MS-bSSFP model was built that can be used to fit conversion rate constants for these experiments. The model was validated in vivo using paired animal (healthy rat kidneys n = 8, transgenic adenocarcinoma of the mouse prostate n = 3) and human renal cell carcinoma (n = 3) datasets. Gradient echo (GRE) acquisitions were used with a previous GRE model to compare to the results of the proposed GRE-bSSFP model. Within simulations, the proposed GRE-bSSFP model fits the simulated data well, whereas a GRE model shows bias because of model mismatch. For the in vivo datasets, the estimated conversion rate constants using the proposed GRE-bSSFP model are consistent with a previous GRE model. Jointly fitting the lactate T2 with kPL resulted in less precise kPL estimates. The proposed GRE-bSSFP model provides a method to estimate conversion rate constants, kPL and kPB, for MS-bSSFP HP 13C experiments. This model may also be modified and used for other applications, for example, estimating rate constants with other hyperpolarized reagents or multi-echo bSSFP.

Cryo-EM structures elucidate the multiligand receptor nature of megalin

Megalin (low-density lipoprotein receptor-related protein 2) is a giant glycoprotein of about 600 kDa, mediating the endocytosis of more than 60 ligands, including those of proteins, peptides, and drug compounds [S. Goto, M. Hosojima, H. Kabasawa, A. Saito, Int. J. Biochem. Cell Biol. 157, 106393 (2023)]. It is expressed predominantly in renal proximal tubule epithelial cells, as well as in the brain, lungs, eyes, inner ear, thyroid gland, and placenta. Megalin is also known to mediate the endocytosis of toxic compounds, particularly those that cause renal and hearing disorders [Y. Hori et al., J. Am. Soc. Nephrol. 28, 1783-1791 (2017)]. Genetic megalin deficiency causes Donnai-Barrow syndrome/facio-oculo-acoustico-renal syndrome in humans. However, it is not known how megalin interacts with such a wide variety of ligands and plays pathological roles in various organs. In this study, we elucidated the dimeric architecture of megalin, purified from rat kidneys, using cryoelectron microscopy. The maps revealed the densities of endogenous ligands bound to various regions throughout the dimer, elucidating the multiligand receptor nature of megalin. We also determined the structure of megalin in complex with receptor-associated protein, a molecular chaperone for megalin. The results will facilitate further studies on the pathophysiology of megalin-dependent multiligand endocytic pathways in multiple organs and will also be useful for the development of megalin-targeted drugs for renal and hearing disorders, Alzheimer's disease [B. V. Zlokovic et al., Proc. Natl. Acad. Sci. U.S.A. 93, 4229-4234 (1996)], and other illnesses.

Targeted Restoration of GPX3 Attenuates Renal Ischemia/Reperfusion Injury by Balancing Selenoprotein Expression and Inhibiting ROS-mediated Mitochondrial Apoptosis.

Renal ischemia/reperfusion (IR) injury is the leading cause of acute kidney injury in both autologous and transplanted kidneys. Low-level glutathione peroxidase 3 (GPX3) is associated with renal IR injury. The exact mechanism of targeted GPX3 restoration in renal IR injury has yet to be determined. The distribution of GPX3 in different tissues and organs of the body was investigated. The level of GPX3 in renal IR injury was assessed. To confirm the action of GPX3 and its mechanisms, IR models were used to introduce adeno-associated virus 9 containing GPX3, as well as hypoxia/reoxygenation-exposed normal rat kidney cells that consistently overexpressed GPX3. Reverse molecular docking was used to confirm whether GPX3 was a target of ebselen. GPX3 is abundant in the kidneys and decreases in expression during renal IR injury. GPX3 overexpression reduced renal IR injury and protected tubular epithelial cells from apoptosis. Proteomics analysis revealed a strong link between GPX3 and mitochondrial signaling, cellular redox state, and different expression patterns of selenoproteins. GPX3 inhibited reactive oxygen species-induced mitochondrial apoptosis and balanced the disordered expression of selenoproteins. GPX3 was identified as a stable selenoprotein that interacts with ebselen. Ebselen enhanced the level of GPX3 and reduced IR-induced mitochondrial damage and renal dysfunction. Targeted restoration of GPX3 attenuates renal IR injury by balancing selenoprotein expression and inhibiting reactive oxygen species-mediated mitochondrial apoptosis, indicating that GPX3 could be a potential therapeutic target for renal IR injury.