Renal Damage Research Articles

Abstract P447: Impact of Altered Receptor Expression On the Cardiovascular Response to Estrogen

Premenopausal women benefit from estrogen's protective effects, including lower arterial stiffness than men of the same age. Despite estrogen's protective role, menopausal hormone therapy showed no cardiovascular benefits in the Women's Health Initiative. One theory is that the response to menopausal hormone therapy is modulated by the presence of pre-existing cardiovascular disease. Estrogen signals through nuclear estrogen receptors ERα and ERβ, and the membrane-bound G protein-coupled estrogen receptor (GPER). Our lab has shown that GPER induces protective cardiovascular effects including decreased blood pressure, protection from renal damage, and attenuation of arterial remodeling. In this study, we hypothesized that GPER deletion would attenuate the protective vascular effects of estrogen after menopause. Female C57Bl/6J wildtype (wt) and global GPER knockout (ko) mice underwent ovariectomy (OVX) at 46 weeks of age and concurrently administered estrogen (E) or vehicle (Veh). Angiotensin II (Ang II; 700 ng/kg/day) infusion was used to induce hypertension either four weeks prior (Ang-E) or at the time of OVX (E-Ang) to evaluate the impact of cardiovascular diseases preceding or coinciding with menopause. Blood pressure was measured by tail-cuff plethysmography and arterial stiffness was assessed by pulse wave velocity (PWV). Statistical analysis was performed using one-way ANOVA. Ang II induced a similar level of hypertension in wt and ko mice and was not impacted by E or timing. In wt mice, PWV was significantly higher in Veh-treated compared with E-treated hypertensive animals, independent of timing (P<0.001). In contrast, PWV was not impacted by E in GPER ko mice (P=0.99). In conclusion, we found that E did not affect the hypertensive response to Ang II in both wt and GPER ko mice. GPER deletion reduced estrogen’s protection from arterial stiffening. Whether Ang II preceded or coincided with menopause did not alter the effects of E. These studies are important for determining whether cardiovascular status should be a factor when considering menopausal hormone therapy.

The Effect of Obstructive Sleep Apnea on Subclinical Target Organ Damage in Patients With Resistant Hypertension

IntroductionAmong all patients with hypertension, those with resistant hypertension (RH) have the highest rates of subclinical organ damage (SOD). The prevalence of obstructive sleep apnea (OSA) is high in RH patients, and it could contribute to SOD. We aimed to investigate how OSA and its treatment are related to SOD in a large cohort of RH patients. MethodsThis is an ancillary analysis to the SARAH study, a multicentre observational cohort aiming to evaluate the impact of OSA on RH. Individuals with RH who were undergoing a sleep study and have information on at least one of the SOD variables (vascular, cardiac or renal damage) were selected. Patients were followed-up for three years. ResultsIn total, 503 subjects were included. The participants were predominantly male, obese, and the median (IQR) apnea–hypopnea index (AHI) was 15.5 (7.90–31.5)events/h. No differences in the presence of vascular or cardiac damage were observed between OSA and non-OSA patients. A lower estimated glomerular filtration rate (eGFR) was observed in participants with OSA than in those without OSA, with an adjusted effect of −8.69mL/min/1.73m2 (−13.59, −3.79; p value<0.001). Kidney damage was also greater in subjects with OSA, with an adjusted OR (95% CI) of 1.77 (1.09, 2.87; p value=0.02). The eGFR showed a linear dose–response relationship with OSA severity. Among patients treated with CPAP, lower eGFR values were observed in noncompliant subjects. ConclusionsOSA could contribute to worsening renal function in patients with RH. No compliance with CPAP was associated with lower values of eGFR.

Urinary extracellular vesicles as a monitoring tool for renal damage in patients not meeting criteria for chronic kidney disease.

Current definition of chronic kidney disease (CKD) identifies only advanced stages, but effective management demands early detection. Urinary albumin-to-creatinine ratio (ACR) 30mg/g is a cut-off point for CKD clinical diagnosis. Patients with lower values (normoalbuminuria) and eGFR>60mL/min/1.73m2 are considered at no increased cardiorenal risk. However, higher incidence of renal function decline and cardiovascular events have been shown within the normoalbuminuria range. Novel subclinical indicators may help to identify higher-risk patients. Urinary extracellular vesicles (uEVs) are sentinels of renal function non-invasively. Here we aimed to approach the early assessment of cardiorenal risk by investigating the protein cargo of uEVs. Hypertensive patients were classified in control group (C) with ACR<10mg/g, and high-normal group (HN) with ACR 10-30mg/g. Isolated uEVs were characterized by western blotting and electron microscopy and the protein cargo was analyzed by untargeted proteomics (LC-MS/MS) in a first discovery cohort. Protein confirmation was performed in a different cohort by ExoView. Immunohistochemistry of human kidney biopsies was also performed to evaluate the potential of uEVs to reflect renal damage. HN albuminuria does not affect the uEVs concentration, size, or tetraspanin profile. Among >6200 uEVs proteins identified, 43 define a panel significantly altered in HN patients without variation in urine, mostly annotated in the tubule (39 out of 43). The tubular transporter long-chain fatty acid transport protein 2 (SLC27A2) and the apical membrane protein amnionless (AMN) confirmed their alteration in HN patients evidencing impaired tubular reabsorption. SLC27A2 showed tubular expression and significantly reduced levels in patients with diagnostic criteria for CKD. Alterations in the EV-mediated molecular profile are evident before pathological ACR levels are reached. Direct quantitation of SLC27A2 and AMN in uEVs helps identifying normoalbuminuric subjects with higher cardiorenal risk in early monitoring of CKD.

313. CLINICAL EVALUATION OF PEMBROLIZUMAB PLUS CISPLATIN AND FLUOROURACIL AS INDUCTION FOR PATIENTS WITH CT4B ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract Background Definitive chemoradiotherapy (dCRT) is a standard treatment for patients with cT4b esophageal squamous cell cancer (ESCC). In these 3 decades, radiation technique has been improved, and chemotherapy with cisplatin, fluorouracil, and/or taxans was combined before and after dCRT. However, its CR rate remains around 25% and its 3-year survival rate also remains below 30%. Although conversion surgery has been applied to improve the survival of these patients, no study has shown significant superiority to CR after dCRT in survival to date. Chemotherapy of pembrolizumab plus cisplatin and fluorouracil was applied to patients with unresectable or recurred esophageal cancer and demonstrated significant survival benefit and good objective response. We provided this therapy as induction to improve the therapeutic result of patients with cT4b ESCC. Method From April 2022 to August 2023, 11 untreated patients with cT4b ESCC had this chemotherapy as induction, with pembrolizumab 200 mg plus chemotherapy (5-fluorouracil 800 mg/m2 on days 1-5 plus cisplatin 80 mg/m2 on day 1) once every 3 weeks. Patients with cervical lymph node metastasis were included. After 2 or 3 cycles, the therapeutic effect was evaluated according to RECIST. Adverse events were evaluated according to CTCAE. Result Average age was 70, and 3 patients had cervical lymph node metastasis. Objective response rate was 82% (CR 1, PR 8). In these 9 patients, the volume of tumors shrank by more than 60% within 11 weeks. Over Grade 3 neutropenia developed in 2 (18%), but no G-CSF was administered. Gastric ulcer perforation developed in 1 (9%). In 2 patients, the dose of cisplatin should be modified due to renal damage. One patient had prolonged renal damage and had conversion surgery after 1 cycle. Eight patients had dCRT. One of 8 terminated dCRT due to another disease. Two of 8 just finished dCRT, and one is under dCRT. Of 3 were evaluated as CR, and followed without any treatment. Local and lymphatic recurrence developed in one PR patient. To date, no specific adverse events relating to pembrolizumab developed during and after dCRT. Of the 2 had conversion surgery without any severe post-operative complications. Discussion and Conclusion In our preliminary study, chemotherapy of pembrolizumab plus cisplatin and fluorouracil showed good objective response (82%) and early tumor shrinkage (more than 60% within 11 weeks). Over grade 3 hematological adverse events developed in only 18% of patients. These results suggest this regimen could be administered to patients with cT4b ESCC as induction especially followed by dCRT. This regimen can reduce tumor volume and control lymphatic spread, and these factors seem to improve prognosis and prevent fatal complications such as fistula or stricture of patients with cT4b ESCC who have dCRT. We plan a clinical trial of this chemotherapy followed by dCRT for patients with cT4b ESCC.

ANKRD1 aggravates renal ischaemia‒reperfusion injury via promoting TRIM25-mediated ubiquitination of ACSL3.

Renal ischaemia‒reperfusion injury (IRI) is the primary cause of acute kidney injury (AKI). To date, effective therapies for delaying renal IRI and postponing patient survival remain absent. Ankyrin repeat domain 1 (ANKRD1) has been implicated in some pathophysiologic processes, but its role in renal IRI has not been explored. The mouse model of IRI-AKI and in vitro model were utilised to investigate the role of ANKRD1. Immunoprecipitation-mass spectrometry was performed to identify potential ANKRD1-interacting proteins. Protein‒protein interactions and protein ubiquitination were examined using immunoprecipitation and proximity ligation assay and immunoblotting, respectively. Cell viability, damage and lipid peroxidation were evaluated using biochemical and cellular techniques. First, we unveiled that ANKRD1 were significantly elevated in renal IRI models. Global knockdown of ANKRD1 in all cell types of mouse kidney by recombinant adeno-associated virus (rAAV9)-mitigated ischaemia/reperfusion-induced renal damage and failure. Silencing ANKRD1 enhanced cell viability and alleviated cell damage in human renal proximal tubule cells exposed to hypoxia reoxygenation or hydrogen peroxide, while ANKRD1 overexpression had the opposite effect. Second, we discovered that ANKRD1's detrimental function during renal IRI involves promoting lipid peroxidation and ferroptosis by directly binding to and decreasing levels of acyl-coenzyme A synthetase long-chain family member 3 (ACSL3), a key protein in lipid metabolism. Furthermore, attenuating ACSL3 in vivo through pharmaceutical approach and in vitro via RNA interference mitigated the anti-ferroptotic effect of ANKRD1 knockdown. Finally, we showed ANKRD1 facilitated post-translational degradation of ACSL3 by modulating E3 ligase tripartite motif containing 25 (TRIM25) to catalyse K63-linked ubiquitination of ACSL3, thereby amplifying lipid peroxidation and ferroptosis, exacerbating renal injury. Our study revealed a previously unknown function of ANKRD1 in renal IRI. By driving ACSL3 ubiquitination and degradation, ANKRD1 aggravates ferroptosis and ultimately exacerbates IRI-AKI, underlining ANKRD1's potential as a therapeutic target for kidney IRI. Ankyrin repeat domain 1 (ANKRD1) is rapidly activated in renal ischaemia‒reperfusion injury (IRI) models in vivo and in vitro. ANKRD1 knockdown mitigates kidney damage and preserves renal function. Ferroptosis contributes to the deteriorating function of ANKRD1 in renal IRI. ANKRD1 promotes acyl-coenzyme A synthetase long-chain family member 3 (ACSL3) degradation via the ubiquitin‒proteasome pathway. The E3 ligase tripartite motif containing 25 (TRIM25) is responsible for ANKRD1-mediated ubiquitination of ACSL3.

SS-31 protects diabetic nephropathy progression: A systematic review of in vivo and in vitro studies

Context: Diabetic nephropathy is the leading cause of end-stage renal disease and also death in the world. Administration of Szeto-Schiller-31 (SS-31) as a potential therapeutic candidate that can decrease the renal function damage progressivity in diabetes needs to be comprehensively analyzed. Aims: To assess the protective effects of SS31 against the progressivity of diabetic nephropathy. Methods: This systematic review follows PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines 2020. Searches of databases (Pubmed, Science Direct, Scopus, ProQuest, and Springer) were done on 17 September 2023 in order to find articles related to the animal diabetic model and SS-31 treatment. Manual searches from medRxiv were also conducted to obtain additional evidence. Renal function, histopathology analysis, reactive oxygen species in vivo, and in vitro analysis were described. Results: There were six in vivo studies, each of which discussed the renal function, histopathology, and reactive oxygen species (ROS), and four in vitro studies that discussed ROS. The available data suggested that SS-31 improves kidney function by lowering urinary albumin excretion, proteinuria, serum creatinine, creatinine clearance, and BUN, supported by histopathological improvements. In addition, SS-31 also has the effect of lowering 8-hydroxy-2-deoxyguanosine (8-OHdG) level, malondialdehyde (MDA) level, and nicotinamide adenine dinucleotide phosphate (NADPH) expression. Conclusions: SS31 had a renoprotective effect that could prevent the worsening of renal function in diabetic mice. In addition, the results of histopathology and ROS analysis also support the positive results of SS-31 treatment. Further studies are required to confirm its findings.

Inhibition of HDAC8 mitigates AKI by reducing DNA damage and promoting homologous recombination repair.

Nephrotoxicity is a major side effect of platinum-based antineoplastic drugs, and there is currently no available therapeutic intervention. Our study suggests that targeting histone deacetylase 8 could be a potential treatment for cisplatin-induced acute kidney injury (AKI). In a murine model of AKI induced by cisplatin, the administration of PCI-34051, a selective inhibitor of HDAC8, resulted in significant improvement in renal function and reduction in renal tubular damage and apoptosis. Pharmacological inhibition of HDAC8 also decreased caspase-3 and PARP1 cleavage, attenuated Bax expression and preserved Bcl-2 levels in the injured kidney. In cultured murine renal epithelial cells (mRTECs) exposed to cisplatin, treatment with PCI-34051 or transfection with HDAC8 siRNA reduced apoptotic cell numbers and diminished expression of cleaved caspase-3 and PARP1; conversely, overexpression of HDAC8 intensified these changes. Additionally, PCI-34051 reduced p53 expression levels along with those for p21, p-CDK2 and γ-H2AX while preserving MRE11 expression in the injured kidney. Similarly, pharmacological and genetic inhibition of HDAC8 reduced γ-H2AX and enhanced MRE11 expression; conversely, HDAC8 overexpression exacerbated these changes in mRTECs exposed to cisplatin. These results support that HDAC8 inhibition attenuates cisplatin-induced AKI through a mechanism associated with reducing DNA damage and promoting its repair.

Huangqi-Danshen Decoction Against Renal Fibrosis in UUO Mice via TGF-β1 Induced Downstream Signaling Pathway.

Huangqi-Danshen decoction (HDD) is a Chinese medicinal herb pair with good efficacy in treating chronic kidney disease, but its mechanism needs to be clarified. To uncover the underlying mechanism of HDD antagonizing renal fibrosis through network pharmacology (NP) analysis and experimental validation. The chemical components of water extract of HDD were analyzed by combining the ultra-high performance liquid chromatography coupled with Q-Exactive mass spectrum analysis (UHPLC-QE-MS) and HERB database. NP was used to identify core common targets of HDD components and renal fibrosis. Subsequently, male C57BL/6 mice were divided into Sham, unilateral ureteral obstruction (UUO) and UUO+HDD groups. Renal function, histopathology, Western blotting, and immunohistochemistry analyses were used to evaluate the protective effect of HDD on UUO mice. The effects of HDD on signaling pathways were validated in both UUO mice and transforming growth factor-β1 (TGF-β1)-induced HK-2 cells. By combining UHPLC-QE-MS analysis and HERB database, 25 components were screened in HDD extract. There were 270 intersection targets of the 25 components and renal fibrosis. Based on their scores in protein-protein interaction analysis and degree values in component-pathway-target triadic network, 6 core common targets of the 25 components and renal fibrosis were identified, namely phosphoinositide 3-kinase (PI3K), signal transducer and activator of transcription 3(Stat3), non-receptor tyrosine kinase Src (Src), epidermal growth factor receptor (EGFR), matrix metalloproteinase 9 (MMP9), and MMP2. HDD ameliorated renal tubular damage and collagen deposition and downregulated fibrosis-related proteins expression in UUO mice. Furthermore, HDD was demonstrated to reduce PI3K, Stat3, Src, EGFR, and MMP2 expressions, and enhance MMP9 expression in the kidney of UUO mice and in TGF-β1-induced HK-2 cells. HDD can alleviate renal fibrosis which may be related to regulating the expression of essential proteins in the epithelial-mesenchymal transition and extracellular matrix production/degradation signaling pathways.

Abstract 38: Loop Diuretic Resistance in a Preclinical Model of Cardiorenal Syndrome 2: Role of Enhanced Distal Convoluted Tubule Sodium Transport

Nearly 60% of heart failure (HF) patients develop a progressive decline in kidney function. Decompensated HF also causes edema, usually treated with loop diuretics, like furosemide, that inhibit the Na-K-2Cl cotransporter NKCC2 in the thick ascending limb (TAL). However, nearly 50% of HF patients do not respond adequately to loop diuretics and become resistant. The mechanisms causing loop diuretic resistance are unclear but may involve TAL-dependent and independent mechanisms. Few have used the mouse as a model of cardiorenal syndrome due to its resistance to renal damage. We hypothesize that mice develop loop diuretic resistance and lower GFR after chronic HF induced by myocardial infarction (MI). MI was induced in C57Bl6J mice through ligation of the left anterior descending coronary artery and compared to a sham surgery group. We assessed heart function by echocardiography and GFR (FITC inulin) in conscious mice. The response to diuretics was studied in metabolic cages. MI mice had a 50% reduction in ejection fraction (EF) one month after MI (MI: 29.94 ± 1.94, Sham: 67.02 ± 1.14%, n= 8, p&lt;0.05). EF was still lower 3 and 6 months after MI. The MI group showed decreased GFR, 6 months after MI (MI: 0.50 ± 0.06, Sham: 0.75±0.05 µl/min, n= 5, p&lt;0.05). Urinary albumin was similar in both groups (n=8). In metabolic cages, a saturating dose of the NKCC2 inhibitor bumetanide (20 mg/Kg), induced diuresis and natriuresis in sham mice (Delta UV: 1.96 ± 0.27 ml/4h, Delta UNa: 117.2 ± 11.02µmols/4h, n= 6) but had an attenuated response in MI mice (Delta UV: 0.88 ± 0.23 ml/4h, Delta UNa: 65.00 ± 4.53 µmols/4h, n= 4, p&lt;0.05 vs sham). To study the distal convoluted tubule (DCT) we measured the response to hydrochlorothiazide (HCTZ). HCTZ (100 mg/Kg) induced a natriuretic response in sham mice (Delta UNa: 75.24±11.18µmols/4h, n= 10) and a higher response in the MI group (Delta UNa: 129.54±11.59µmols/4h, n= 12, p&lt;0.05 vs sham). RNAseq in isolated mTALs from MI and sham mice identified 85 up- and 160 down-regulated genes (n=5, p&lt;0.025). Up-regulated genes involved those in the sphingosine pathway, protein trafficking, PKA signaling (PDE4B, PRKD2) and cell growth/tubule differentiation (FREM2, WFDC1). mRNA expression of TAL NaCl transporters was not affected. We conclude that HF decreases GFR, induces loop diuretic resistance and affects mTAL signaling in mice. Loop diuretic resistance may involve enhanced DCT NaCl reabsorption.

P224 EFFECT OF SODIUM NITRITE ON RENAL DAMAGE FROM 2-KIDNEY, 1-CLIP (2K-1C) HYPERTENSION IN RATS

Renovascular hypertension is characterized by oxidative stress and decreased availability of nitric oxide (NO). Nitrite is a physiologically recycled metabolite that generates NO. Treatment with sodium nitrite has antihypertensive effects due to its antioxidant capacity. However, the renal effects of this treatment are not known in 2K1C hypertension. This study aims to evaluate the effect of treatment with sodium nitrite on kidney damage caused by 2K1C hypertension. Hypertension was induced by cleavage of the left renal artery in Wistar rats. Two weeks after surgery, the animals were treated with two doses (1 mg/kg/day or 15 mg/kg/day) of sodium nitrite or vehicle for 4 weeks, by gavage. Blood pressure (BP) was checked weekly by tail plethysmography. To assess renal function, plasma urea and creatinine were determined. Kidney oxidative stress was evaluated through the activity of catalase (CAT), superoxide dismutase (SOD), levels of reduced glutathione (GSH), lipid peroxidation, and superoxide (O2-) levels. Treatment with 15 mg/kg/day of sodium nitrite reversed the increase in BP in 2K1C rats (p&lt;0.05, 2K1C:170.5±6.542; 2K1C+Nitrite15:162.4±6.712 mmHg), and improved renal function previously impaired by hypertension (urea, p&lt;0.05; 2K1C:76.37±24.53; 2K1C+Nitrite15:47.82±13.86; creatinine, p&lt;0.05; 2K1C:0.540±0.105; 2K1C+Nitrite15:0.3550±0.117). SOD activity decreased in the kidneys of hypertensive animals (p&lt;0.05, Control:0.7176±0.06426; 2K1C:0.636±0.0888; 2K1C+Nitrite1:0.703±0.0866; 2K1C+Nitrite15:0.648±0.173). As for CAT and GSH, there was a decrease in activity in hypertensive animals, with improvement in the group treated with nitrite 15 mg/kg/day (CAT p&lt;0.05, Control:0.651±0.255; 2K1C:0.2772±0.1837; 2K1C+Nitrite15: 0.6654±0.1440 and GSH: p&lt;0.05, Control:44.80±10.59; 2K1C: 29,62±7,253 2K1C+Nitrite15:44.25±10.07). Lipid peroxidation increased by hypertension was reduced with treatment at the highest dosage (p&lt;0.05, Control:0.314±0.158; 2K1C:0.497±0.113; 2K1C+Nitrite15:0.278±0.084). O2- levels were decreased in all groups treated with nitrite (p&lt;0.05, 2K1C:3.844±1.598; 2K1C+Nitrite1:0.9643±0.2063; 2K1C+Nitrite15:0.4431±0.1838). Our results suggest that sodium nitrite treatment improves 2K1C renal damage through its antioxidant activity. Acknowledgments: FAPEMIG# APQ-00946-23, CNPq# 302076/2022-0

SIRT1/NOX1 pathway mediated ameliorative effects of rosmarinic acid in folic acid-induced renal injury

Background and purpose: Renal injury is a serious disorder that can be caused by some diseases or agents. Rosmarinic acid (RA) is a natural and safe compound with powerful antioxidant and anti-inflammatory properties. In this study, the ameliorative effects of RA were assayed in folic acid (FA)-induced renal injury by involving the SIRT1/NOX1 pathway. Experimental approach: Thirty-six male C57/BL6 mice were divided into 6 groups (n = 6) including control, vehicle, FA, RA, FA + RA 50, and FA + RA 100. After 10 days, blood urea nitrogen (BUN), creatinine, and oxidative stress were measured. The expression of SIRT1 and NOX1 proteins was evaluated by western blot. Also, histopathological alterations were assayed by H&amp;E and PAS staining methods. Findings/Results: BUN and creatinine were significantly higher in the FA group compared to the control group; however, their levels decreased after RA treatment in both doses. A significant decrease was observed in swelling, necrosis, and desquamation of tubular epithelial cells in the FA + RA 50 and FA + RA 100 groups compared to the FA group. RA in the animals receiving FA increased SIRT1 expression and the levels of GSH and SOD compared to the FA group. RA in the animals receiving FA showed a significant decrease in NOX1 expression and MDA level compared to the FA group. Conclusion and implications: The findings declared that the administration of RA has positive effects against renal damage induced by FA. The effect might result from involvement in the SIRT1/NOX1 pathway and thereby attenuation of oxidative stress.

Integrating transcriptomics, metabolomics, and network pharmacology to investigate multi-target effects of Sporoderm-broken spores of Ganoderma lucidum on improving HFD-induced diabetic nephropathy rats

Diabetes mellitus (DM) is a major metabolic disease endangering global health, with diabetic nephropathy (DN) as a primary complication lacking curative therapy. Sporoderm-broken spores of Ganoderma lucidum (GLP), an herbal medicine, has been used for the treatment of metabolic disorders. In this study, DN was induced in Sprague-Dawley rats using streptozotocin (STZ) and a high-fat diet (HFD), and the protective mechanisms of GLP were investigated through transcriptomic, metabolomic, and network pharmacology analyses. Our results demonstrated that GLP intervention ameliorated renal damage and inflammation levels in DN rats. Integrative metabolomic and transcriptomic analysis revealed that GLP treatment modulated glucose and cellular energy metabolisms by regulating relevant genes. GLP significantly suppressed the inflammations by impacting glucose and energy metabolism-related gene expression (Igfbp1 and Angptl4) and enhanced metabolic biomarkers of 4-Aminocatechol. In addition, network pharmacology analysis further indicated that GLP may efficiently alleviate DN via immune-related pathways. In conclusion, this study provides supportive evidence of the anti-inflammatory effects of GLP supplements, highlighting their potential for promising clinical applications in treating diabetic nephropathy.

MSU crystallization promotes fibroblast proliferation and renal fibrosis in diabetic nephropathy via the ROS/SHP2/TGFβ pathway

Monosodium urate (MSU) crystallisation deposited in local tissues and organs induce inflammatory reactions, resulting in diseases such as gout. MSU has been recognized as a common and prevalent pathology in various clinical conditions. In this study, we investigated the role of MSU in the pathogenesis of diabetic kidney disease (DKD). We induced renal injury in diabetic kidney disease mice using streptozotocin (STZ) and assessed renal histopathological damage using Masson's trichrome staining and Collagen III immunofluorescence staining. We measured the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and uric acid (UA) using ELISA. Protein expression levels of NLRP3, p-NF-κB, SHP2, p-STAT3, and p-ERK1/2 were analyzed by Western blot. To further investigate the role of MSU in diabetic kidney disease, we conducted in vitro experiments. In our in vivo experiments, we found that compared to the Model group, there was a significant increase in interstitial fibrosis in the kidneys of mice after treatment with MSU, accompanied by elevated levels of MDA, SOD, and UA. Furthermore, the protein expression of NLRP3, p-NF-NB, SHP2, p-STAT3, and p-ERK1/2 was upregulated. In our subsequent studies on mouse fibroblasts (L929 cells), we discovered that high glucose, MSU, and TGF-β could promote the expression of P22, GP91, NLRP3, NF-κB, p-NF-κB, p-SHP2, p-EGFR, p-STAT3, and Collagen-III proteins. Additionally, we found that SHP2 could counteract the upregulation trend induced by MSU on the expression of p-SHP2, p-EGFR, p-STAT3, and Collagen-III proteins, and inhibitors YQ128, NAC, and Cetuximab exhibited similar effects. Furthermore, immunofluorescence results indicated that SHP2 could inhibit the expression of the fibrosis marker α-SMA in L929 cells. These findings suggest that MSU can promote renal fibroblast SHP2 expression, induce oxidative stress, activate the NLRP3/NF-κB pathway, and enhance diabetic kidney disease fibroblast proliferation through the TGFβ/STAT3/ERK1/2 signaling pathway, leading to renal fibrosis.

Protective Effects of Spermacoce hispida Against Cisplatin-Induced Nephrotoxicity: A Study on Oxidative and Nitrosative Stress

Background: Nephrotoxicity is a common and severe side effect of cisplatin, a widely used chemotherapeutic agent. The mechanism of cisplatin-induced nephrotoxicity involves oxidative stress, inflammation, and apoptosis, leading to renal damage. There is growing interest in exploring natural products with antioxidant and anti-inflammatory properties as potential protective agents against drug-induced nephrotoxicity.Objective: The present study aimed to investigate the protective effects of Spermacoce hispida against cisplatin-induced nephrotoxicity in an in vivo rat model. Methods: S. hispida was collected, and plant extracts were prepared using different solvents. The prepared extracts underwent phytochemical screening. Nephrotoxicity was induced in rats through a single intraperitoneal injection of cisplatin at a dose of 5 mg/kg. S. hispida extracts at a dose of 100 mg/kg were administered to assess their protective activity. Key parameters measured included blood urea nitrogen (BUN), serum creatinine, oxidative stress markers, proinflammatory cytokines, nitric oxide (NO) levels, and histological alterations in kidney tissue.Results: Cisplatin treatment resulted in increased levels of BUN, serum creatinine, and proinflammatory cytokines in rats, indicating nephrotoxicity. However, treatment with S. hispida extracts for 14 days significantly decreased these elevated levels. Additionally, S. hispida treatment reduced oxidative stress and NO production in cisplatin-treated rats. Histological examination revealed that cisplatin induced structural damage in kidney tissues, which was normalized by S. hispida treatment. Conclusion: The study concludes that Spermacoce hispida exhibits nephroprotective activity, likely by inhibiting oxidative stress and NO production, thereby mitigating cisplatin-induced nephrotoxicity in rats

Research on Experimental Hypertension in Prague (1966-2009).

The study of ontogenetic aspects of water and electrolyte metabolism performed in the Institute of Physiology (Czechoslovak Academy of Sciences) led to the research on the increased susceptibility of immature rats to salt-dependent forms of hypertension since 1966. Hemodynamic studies in developing rats paved the way to the evaluation of hemodynamic mechanisms during the development of genetic hypertension in SHR. A particular attention was focused on altered renal function and kidney damage in both salt and genetic hypertension with a special respect to renin-angiotensin system. Renal damage associated with hypertension progression was in the center of interest of several research groups in Prague. The alterations in ion transport, cell calcium handling and membrane structure as well as their relationship to abnormal lipid metabolism were studied in a close cooperation with laboratories in Munich, Glasgow, Montreal and Paris. The role of NO and oxidative stress in various forms of hypertension was a subject of a joint research with our Slovak colleagues focused mainly on NO-deficient hypertension elicited by chronic L-NAME administration. Finally, we adopted a method enabling us to evaluate the balance of vasoconstrictor and vasodilator mechanisms in BP maintenance. Using this method we demonstrated sympathetic hyperactivity and relative NO deficiency in rats with either salt-dependent or genetic hypertension. At the end of the first decennium of this century we were ready to modify our traditional approach towards modern trends in the research of experimental hypertension. Keywords: Salt-dependent hypertension o Genetic hypertension o Body fluids o Hemodynamics o Ion transport o Cell membrane structure and function o Renal function o Renin-angiotensin systems.

The Value of Bedside Ultrasound Evaluation of Intravenous Ultrasound Grading System Combined with TyG Index in Predicting Acute Renal Injury in Patients with Acute Hyperlipidemic Pancreatitis.

Aims/Background Bedside ultrasound evaluation of venous excess ultrasound (VExUS) combined with the triglyceride-glucose (TyG) index plays an important role in predicting acute kidney injury (AKI) in patients with acute hyperlipidemic pancreatitis. VExUS can effectively evaluate the degree of venous congestion, while the TyG index is valuable in predicting severe pancreatitis. The combination of these two methods is expected to provide a more accurate AKI risk assessment tool for clinical practice. This study explores the value of combining bedside ultrasound evaluation using the VExUS grading system with the TyG index in predicting acute renal damage in patients with acute hyperlipidemic pancreatitis. Methods From January 2021 to December 2023, 110 patients with acute hyperlipidemic pancreatitis were selected. The patients were divided into two groups based on whether they were complicated with acute kidney injury (AKI): the AKI group (n = 23) and the non-AKI group (n = 87). The general data of the two groups were compared, and the risk factors for AKI in patients with acute hyperlipidemic pancreatitis were analyzed using multivariate logistic regression. The predictive value was assessed using receiver operating characteristic curve (ROC) analysis. Results There were no statistically significant differences in age, gender, outcome, triglyceride (TG), total cholesterol, low-density lipoprotein (LDL) levels at admission, blood nutrition at discharge, creatinine (CREA) at discharge, underlying diseases, start time of enteral nutrition, complications, length of stay, Intensive Care Unit (ICU) days, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, blood glucose level, blood amylase level, CREA, blood urine nitrogen (BUN), blood purification treatment (p > 0.05). However, there were significant differences (p < 0.05) between the TyG index and the VExUS score, with variables including the TyG index and the VExUS score (included in the logistic regression analysis as variables), and AKI (AKI = 1, non-AKI = 0) as dependent variables. Multiple logistic regression results showed that the TyG index and VExUS score were independent predictors of AKI in patients with acute hyperlipidemia pancreatitis (p < 0.05). The standard error, sensitivity and specificity of the TyG index, VExUS score and combined model for predicting AKI in these patients were 0.064, 73.91 and 87.45; 0.036, 78.16 and 95.65; 0.010, 100.00 and 95.65, respectively (p < 0.05). Conclusion The VExUS score combined with the TyG index is highly valuable in predicting AKI in patients with acute hyperlipidemic pancreatitis.

Perspective and a proposed study to investigate the threat of hypertension and renal damage due to heavy metal pollution of rivers affected by illegal mining activities (galamsey) in Ghana

Perspective and a proposed study to investigate the threat of hypertension and renal damage due to heavy metal pollution of rivers affected by illegal mining activities (galamsey) in Ghana

Serum and urinary monocyte chemoattractant protein-1 as markers of inflammation and renal damage in dogs with naturally occurring leishmaniosis

BackgroundRenal disease in canine leishmaniosis is of great importance owing to increased risk of mortality. In human visceral leishmaniosis, monocyte chemoattractant protein-1 (MCP-1) has been used as a marker of renal damage and inflammation. The purpose of this study was first to determine the serum MCP-1 and urinary MCP-1-to-creatinine ratio (uMCP-1/Cr) in healthy dogs and dogs with leishmaniosis at diagnosis, and second to determine whether these markers can differentiate disease severity at diagnosis.MethodsIn total, 19 healthy seronegative dogs and 38 dogs with leishmaniosis were included in the study. Dogs with leishmaniosis were classified as LeishVet clinical staging and as International Renal Interest Society (IRIS) staging. Serum and urinary MCP-1 concentrations were measured with an enzyme-linked immunosorbent assay. A receiver operating characteristic (ROC) curve determined disease severity at diagnosis between two LeishVet groups (Stage II versus stage III and IV).ResultsDogs in Leishvet stages IIb, III, and IV had a median serum MCP-1 and uMCP-1/Cr concentration higher than healthy dogs (P < 0.0001). No statistical differences were found in serum MCP-1 and uMCP-1/Cr between dogs in LeishVet stage IIa and healthy dogs. The dogs in LeishVet stage IV had significantly higher serum MCP-1 and uMCP-1/Cr compared with the dogs in LeishVet stage IIa (P < 0.0001). Serum MCP-1 and uMCP-1 were significantly higher in dogs in IRIS stage I and II + III + IV compared with healthy dogs. Dogs stage II + III + IV of IRIS had a significantly higher serum MCP-1 compared with dogs in IRIS stage I (P < 0.0001). The area under the ROC curve for serum MCP-1 was 0.78 [95% confidence interval (CI) 0.64–0.93] and for uMCP-1/Cr it was 0.86 (95% CI, 0.74–0.99). The optimal cutoff value for serum MCP-1 and uMCP-1/Cr was 336.85 pg/ml (sensitivity of 79% and specificity of 68%) and 6.89 × 10−7 (sensitivity of 84% and specificity of 79%), respectively.ConclusionsSerum MCP-1 and uMCP-1/Cr are increased in dogs with leishmaniosis compared with healthy dogs, suggesting the presence of inflammation and renal injury. Serum MCP-1 and uMCP-1/Cr were more elevated in the advanced stages of the disease compared with the moderate stages and, therefore, can be markers of the severity of the disease process.Graphical

Analysis of data from the Russian AURA registry (real-world data registry on AlbUminuRia detection rate among patients with previously undiAgnosed chronic kidney disease)

Aim. To present data from the AURA Registry (real-world data registry on AlbUminuRia detection rate among patients with previously undiAgnosed chronic kidney disease). It is important to perform population studies both to study the occurrence of markers (albuminuria (AU), decreased glomerular filtration rate (GFR)) and the prevalence of chronic kidney disease (CKD), which will provide information on the actual detection rate of CKD and the related markers in territories included in the registry of research centers.Material and methods. The article presents the first data from the AURA registry. Recruitment was carried out from March 6, 2023 to January 23, 2024. Thirty-four research centers in various federal districts of the Russian Federation and 104 doctors took part in the recruitment. We included 4580 subjects over the age of 40 years who had no previously established diagnosis of CKD and did not have type 1 or type 2 diabetes. During recruitment, the researchers were guided by the AURA study protocol (Version 1.7/12-26-2022).Results. AU more than 20 mg/g was detected in 64,9% of cases. At the same time, AU is more common at GFR values that may correspond to stage 3A of CKD. The rarer occurrence of AU in those examined with GFR &gt;60 ml/min/1,73 m2 may be explained by less severe renal damage at this CKD stage. The incidence of AU was significantly higher in men, older people, smokers, people with metabolic syndrome, hypertension (HTN), prediabetes and overweight. The occurrence of AU also increased as HTN grade increased. AU detection rate was associated with hypertriglyceridemia, a high blood level of C-reactive protein, which is an integrative marker of inflammation that negatively affects cardiovascular risk.Conclusion. The presented first data from the AURA registry demonstrated the high AU prevalence in people over 40 years of age. A high incidence of AU was typical for patients with HTN, coronary artery disease, atrial fibrillation, heart failure, and prediabetes. An association has been demonstrated between the high incidence of AU and male sex, age, overweight, hyperuricemia, dyslipidemia, and a number of other cardiovascular risk factors.

Benefits of SGLT2 inhibitors on renal and cardiovascular protection, in diabetic patients

Introduction: Type 2 Diabetes Mellitus is major risk factors for both cardiovascular and renal diseases. Managing cardiovascular risk and the progression of renal disease is therefore essential in treating diabetic patient. Sodium-glucose cotransporter-2 inhibitors have been linked to a substantial decrease in cardiovascular and renal mortality, reduced hospitalizations for heart failure and slower progression of renal damage and albuminuria. Objectives: Our study aimed to evaluate the impact of SGLT2i on cardiovascular and renal protection in diabetic patients. Methods: Our study involved elderly patients, with type 2 diabetes, who were divided in two groups, one group received SGLT2i, while the other did not. Data were collected at the start of treatment, as well as at 3, 6, 9 and 12 months thereafter. During each evaluation, we assessed HbA1C, BMI, GFR and renal parameters, uric acid, NTproBNP, echocardiography, and both PAS and PAD values, in both groups. Results: Out of 300 elderly diabetic patients included in the study, 200 were started on dapagliflozin 10 mg. At 12 months, HbA1c, weight, systolic blood pressure, NTproBNP, uric acid, albuminuria, were decreases in group with dapagliflozin versus the other group without it, and estimated glomerular filtration rate was higher (75.3 – 87.19mL/min/1.73m2; p&lt;0.005). Follow up in patients with SGLT2i showed a significant decrease in left ventricular end-diastolic dimension (LV-EDD) (62.86 mm to 54.85 mm; P&lt; 0.001) and improvement in LV-EF. Conclusions: The use of Dapagliflozin demonstrated metabolic benefits in patients with T2DM, including notable decreases in HbA1c, blood pressure, weight, uric acid, and NTproBNP. Additionally, cardiovascular and renal benefits were observed. Therefore, SGLT2i have a significant impact on both cardiovascular and renal protection in diabetic patients.