Sepsis-induced acute kidney injury: kidney protection effects by antioxidants

Sepsis-induced cardiomyopathy: understanding pathophysiology and clinical implications

Sepsis is a life-threatening form of organ dysfunction resulting from a dysregulated response to infection. The complex pathogenesis of sepsis poses challenges because of the lack of reliable biomarkers for early identification and effective treatments. As sepsis progresses to severe forms, cardiac dysfunction becomes a major concern, often manifesting as ventricular dilation, a reduced ejection fraction, and a diminished contractile capacity, known as sepsis-induced cardiomyopathy (SIC). The absence of standardized diagnostic and treatment protocols for SIC leads to varied criteria being used across medical institutions and studies, resulting in significant outcome disparities. Despite the high prevalence of SIC, accurate statistical data are lacking. To understand how SIC affects sepsis prognosis, a thorough exploration of its pathophysiological mechanisms, including systemic factors and complex signalling within myocardial and immune cells, is required. Identifying the factors influencing SIC occurrence and progression is crucial and must be conducted within specific clinical contexts. In this review, the clinical manifestations, pathophysiological mechanisms, and treatment strategies for SIC are discussed, along with the clinical background. We aim to connect current practices with future research challenges, providing clear guidance for clinicians and researchers.

Impact of renal recovery on in-hospital and post-discharge mortality

OBJECTIVE

To verify the impact of renal recovery on mortality in non-critically ill patients with acute kidney injury.

METHOD

A prospective cohort study was carried out in a public hospital in the Federal District with patients with acute kidney injury admitted to a non-critical care unit. Renal recovery was assessed based on the ratio of serum creatinine to baseline creatinine and the patient was followed up for 6 months. Mortality was assessed during hospitalization and after discharge.

RESULTS

Of the 90 patients with hospital-acquired kidney injury, renal recovery was identified in 34.1% to 75% of cases, depending on the time of assessment, considering a follow-up period of up to 6 months. Recovery of renal function during follow-up had an impact on in-hospital mortality [95% CI 0.15 (0.003 - 0.73; p = 0019).

CONCLUSION

Recovery of renal function has been shown to be a protective factor for mortality in patients admitted to the non-critical care unit. Early identification of kidney damage and monitoring of physiological and laboratory variables proved to be fundamental in identifying the severity of the disease and reducing mortality.

Influence of early hemodialysis on the septic acute kidney injury outcome

OBJECTIVE

to analyze the influence of early hemodialysis on the outcome of acute septic kidney injury.

METHOD

this is an observational, analytical, prospective study with patients diagnosed with acute septic kidney injury on hemodialysis. A questionnaire for data collection was used as an instrument. We used the Shapiro-Wilk, nonparametric Kruskal-Wallis, Mann-Whitney U, Student t and chi-square tests for analysis.

RESULTS

of the 40 patients analyzed, 60% were male, with a mean age of 55 (±16.8) years, and length of hospital stay of 43 (±26.2) days. When separating patients undergoing early and late hemodialysis into two groups, an increase in serum creatinine (p = 0.001) was observed in those who underwent late hemodialysis, however, creatinine ≥ 4mg/dl is one of the characteristics of this group. In both groups, there was a high mortality: 62.5% (10) in the early hemodialysis group and 41.7% (10) in the late hemodialysis group, with vasopressor use (p = 0.001) being the main risk factor.

CONCLUSION

early onset of hemodialysis in acute septic kidney injury based on KDIGO definitions did not influence the outcome. However, vasopressor use associated with hemodialysis in septic patients was a predictor of death.

Prognosis of patients with heart disease with acute kidney injury undergoing dialysis treatment

OBJECTIVES

to verify the relationship of cardiovascular diseases with acute kidney injury and assess the prognosis of patients in renal replacement therapy.

METHODS

a cohort study, carried out in a public hospital specialized in cardiology. Treatment, comorbidities, duration of treatment, laboratory tests, discharge and deaths were analyzed.

RESULTS

of the 101 patients, 75 (74.3%) received non-dialysis treatment. The most frequent cardiological diagnoses were hypertension, cardiomyopathies and coronary syndrome. Hospitalization in patients undergoing dialysis was 18 days, hemoglobin <10.5g/dl and anuria in the first days of hospitalization contributed to the type of treatment. Each increase in hemoglobin units from the first day of hospitalization decreases the chance of dialysis by 19.2%. There was no difference in mortality.

CONCLUSIONS

the main cardiological diseases were not predictive of dialysis indication, and clinical treatment was the most frequent. Anuria and anemia were predictors for dialysis treatment.

Alpha-Chymotrypsin Protects Against Acute Lung, Kidney, and Liver Injuries and Increases Survival in CLP-Induced Sepsis in Rats Through Inhibition of TLR4/NF-κB Pathway

Abstract

Inflammation and oxidative stress play a major role in the development of sepsis and its associated complications, leading to multiple organ failure and death. The lungs, liver, and kidneys are among the early affected organs correlated with mortality in sepsis. Alpha-chymotrypsin (α-ch) is a serine protease that exerts anti-inflammatory, anti-edematous, and anti-oxidant properties.

Purpose

This study was undertaken to elucidate if the anti-inflammatory and anti-oxidant effects of α-ch observed in previous studies can alleviate lung, liver, and kidney injuries in a cecal ligation and puncture (CLP)-induced sepsis model, and thus decrease mortality.

Materials and Methods

Septic animals were given α-ch 2 h post CLP procedure. Sepsis outcomes were assessed in the lungs, liver, and kidneys. Separate animal groups were investigated for a survival study.

Results

CLP resulted in 0% survival, while α-chymotrypsin post-treatment led to 50% survival at the end of the study. Administration of α-chymotrypsin resulted in a significant attenuation of sepsis-induced elevated malonaldehyde (MDA) and total nitrite/nitrate (NOx) levels. In addition, there was a significant increase in reduced glutathione (GSH) content and superoxide dismutase (SOD) activity in the lungs, liver, and kidneys. Administration of α-ch reduced elevated tissue expression of toll-like receptor-4 (TLR4), nuclear factor kappa-B (NF-κB), myeloperoxidase (MPO), and inducible nitric oxide synthase (iNOS). Alpha-chymotrypsin resulted in a significant reduction in serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6). Alpha-chymotrypsin attenuated the rise in serum creatinine, cystatin C, blood urea nitrogen (BUN), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels that was observed in the septic group. In addition, α-ch significantly reduced the lung wet/dry weight ratio, total protein content, and leukocytic counts in bronchoalveolar lavage fluid (BALF). Histopathological examination of the lungs, liver, and kidneys confirmed the protective effects of α-ch on those organs.

Conclusion

α-ch has protective potential against sepsis through lowering tissue expression of TLR4, NF-κB, MPO, and iNOS leading to decreased oxidative stress and inflammatory signals induced by sepsis. This effect appeared to alleviate the damage to the lungs, liver, and kidneys and increase survival in rats subjected to sepsis.

Effect of Celecoxib and Infliximab against Multiple Organ Damage Induced by Sepsis in Rats: A Comparative Study

In cases of sepsis, the immune system responds with an uncontrolled release of proinflammatory cytokines and reactive oxygen species. The lungs, kidneys, and liver are among the early impacted organs during sepsis and are a direct cause of mortality. The aim of this study was to compare the effects of infliximab (IFX) and celecoxib (CLX) on septic rats that went through a cecal ligation and puncture (CLP) surgery to induce sepsis. This study included four groups: sham, CLP (untreated), and CLP-treated with CLX or IFX. The administration of “low dose” CLX or IFX was performed after 2 h following the induction of sepsis. Twenty-four hours following the induction of sepsis, the rats were sacrificed and blood samples were collected to evaluate kidney, liver, and lung injuries. MDA and NOx content, in addition to SOD activity and GSH levels, were evaluated in the tissue homogenates of each group. Tissue samples were also investigated histopathologically. In a separate experiment, the same groups were employed to evaluate the survival of septic rats in a 7-day observation period. The results of this study showed that treatment with either CLX or IFX ameliorated the three organs’ damage compared to septic-untreated rats, decreased oxidative stress, enhanced the antioxidant defense, and reduced serum cytokines. As a result, a higher survival rate resulted: 62.5% and 37.5% after the administration of CLX and IFX, respectively, compared to 0% in the CLP group after 7 days. No significant differences were observed between the two agents in all measured parameters. Histopathological examination confirmed the observed results. In conclusion, CLX and IFX ameliorated lung, kidney, and liver injuries associated with sepsis through anti-inflammatory and antioxidant actions, which correlated to the increase in survival observed with both of them.

Influência da hemodiálise precoce no desfecho da lesão renal aguda séptica

RESUMO Objetivo: analisar a influência da hemodiálise precoce no desfecho da lesão renal aguda séptica. Método: estudo observacional, analítico, prospectivo, com pacientes diagnosticados com lesão renal aguda séptica em hemodiálise. Foi utilizado como instrumento um questionário para coleta de dados. Utilizaram-se para análise os testes Shapiro-Wilk, o não paramétrico de Kruskal-Wallis, U de Mann-Whitney, t de Student e do Qui-Quadrado. Resultados: dos 40 pacientes analisados, 60% eram do sexo masculino, com média de 55 (±16,8) anos, e tempo de internação hospitalar de 43 (±26,2) dias. Ao separar em dois grupos, pacientes submetidos à hemodiálise precoce e à hemodiálise tardia, observou-se naqueles que realizaram tardiamente a hemodiálise um aumento de creatinina sérica (p = 0,001), entretanto a creatinina ≥ 4mg/dl é umas das características desse grupo. Em ambos os grupos, houve uma alta mortalidade: 62,5% (10) no grupo de hemodiálise precoce e 41,7% (10) no grupo de hemodiálise tardia, sendo o uso de vasopressor (p = 0,001) o principal fator de risco. Conclusão o início precoce da hemodiálise na lesão renal aguda séptica com base nas definições do KDIGO não influenciou no desfecho. Contudo, o uso do vasopressor associado à hemodiálise em pacientes sépticos foi um fator preditor ao óbito.

Prognóstico de pacientes cardiopatas com injuria renal aguda submetidos a tratamento dialítico

RESUMO Objetivos: verificar a relação de patologias cardíacas com injuria renal aguda e avaliar o prognóstico do paciente em terapia de substituição renal. Métodos: estudo de coorte, realizado em hospital público especializado em cardiologia. O tratamento, comorbidades, tempo de tratamento, exames laboratoriais, alta e óbitos foram analisados. Resultados: dos 101 pacientes, 75 (74,3%) receberam tratamento não dialítico. Os diagnósticos cardiológicos mais frequentes foram hipertensão arterial, miocardiopatias e síndrome coronariana. A internação nos pacientes dialíticos foi de 18 dias, a hemoglobina <10,5g/dl e a anuria nos primeiros dias de internação contribuíram para o tipo de tratamento. Cada aumento de unidade de hemoglobina a partir do primeiro dia de internação diminui em 19,2% a chance de diálise. Não houve diferença na mortalidade. Conclusões: as principais doenças cardiológicas não foram preditivas de indicação de diálise, e o tratamento clínico foi o mais frequente. Anuria e anemia foram preditores para o tratamento dialítico.

Effect of N-acetylcysteine against Vancomycin-Induced Nephrotoxicity: A Randomized Controlled Clinical Trial

BACKGROUND

The proposed mechanism of vancomycin-induced nephrotoxicity (VIN) is indirect production of reactive oxygen species in the kidney tissue. This study aimed to investigate the effectiveness of N-acetylcysteine (NAC), an anti-oxidant agent, in the prevention of VIN.

METHODS

Patients who received vancomycin for any indication were randomly divided to drug (NAC) and control groups. The patients in the drug group received oral NAC 600 mg every 12 hours for 10 days, starting concurrently with vancomycin. Serum creatinine (SCr) levels and blood urea nitrogen (BUN) as well as creatinine clearance (CrCl) and 12-hour urine volume were recorded at baseline, every other day during the study, and 12 hours after the last dose of vancomycin on the 10th day. Furthermore, the cases of acute kidney injury (AKI; ≥ 0.5 mg/dL or at least 50% increase in serum creatinine from baseline) were recorded in the two groups.

RESULTS

Over the study period, 84 and 95 patients completed the study in drug and control groups, respectively. SCr and CrCl were significantly lower and higher, respectively, at all-time points (except for baseline) in the NAC compared to the control group. Furthermore, although not statistically significant, 12 cases of vancomycin-induced AKI were observed in the control group (12.63%), while 4 cases (4.76%) were reported from drug group (P = 0.066; relative risk [RR] = 0.377, 95% CI: 0.126-1.124).

CONCLUSION

NAC has the potential for reduction of VIN. However, more studies are necessary to confirm this effect.

Metabolism and pharmacological activities of the natural health-benefiting compound diosmin

Diosmin is a famous natural flavonoid for treating chronic venous insufficiency and varicose veins.

Aerosol inhalation of a hydrogen-rich solution restored septic renal function

Sepsis-related acute kidney injury (AKI) is known to be caused by inflammation. We explored the renal protective effects of aerosol inhalation of a hydrogen-rich solution (HRS; hydrogen gas dissolved to saturation in saline) in a mouse model of septic AKI. Septic AKI was induced through 18 hours of cecal ligation and puncture. AKI occurred during the early stage of sepsis, as evidenced by increased blood urea nitrogen and serum creatinine levels, pathological changes, renal fibrosis and renal tubular epithelial cell apoptosis, accompanied by macrophage infiltration and M1 macrophage-associated pro-inflammatory cytokine (Il-6 and Tnf-α) generation in renal tissues. Aerosol inhalation of the HRS increased anti-inflammatory cytokine (Il-4 and Il-13) mRNA levels in renal tissues and promoted macrophage polarization to the M2 type, which generated additional anti-inflammatory cytokines (Il-10 and Tgf-β). Ultimately, aerosol inhalation of HRS protected the kidneys and increased survival among septic mice. HRS was confirmed to promote M2 macrophage polarization in lipopolysaccharide-stimulated RAW 264.7 cells. The TGF-β1 receptor inhibitor SB-431542 partly reversed the effects of HRS on renal function, fibrosis, tubular epithelial cell apoptosis and senescence in mice. Thus, HRS aerosol inhalation appears highly useful for renal protection and inflammation reduction in septic AKI.

Protective effects of hesperidin and diosmin against acrylamide-induced liver, kidney, and brain oxidative damage in rats

Acrylamide (AA) is a heat-induced toxin formed during thermal processing of many commonly consumed foods, including meat products, French fries, potato crisps, bread, cereals, cookies, and coffee. There is thus potentially high dietary exposure of humans to AA, which can induce significant oxidative stress. Hesperidin (HS) and diosmin (DS) are flavone glycosides that have antioxidant properties. The aim of this study was to investigate the protective effects of HS and DS against AA toxicity. Fifty-six adult male Wistar albino rats were divided into seven groups. The first group was orally administered 0.5% (w/v) dimethyl sulfoxide (DMSO) and considered as the control group. The second and third groups were orally administered 10 mg/kg/day of HS or DS, respectively. The fourth group received 20 mg/kg/day of AA orally for 14 days. The fifth and sixth groups were given 10 mg/kg/day of HS or DS, respectively, followed by AA. The seventh group was given both HS and DS after AA administration. AA intoxication significantly (p ≤ 0.05) increased serum levels of liver function enzymes (ALT, AST, and ALP), kidney function products (urea and creatinine), oxidative DNA damage marker (OHdG), proinflammatory markers (TNF-α, IL-1β, and IL-6), lipid peroxidation marker (malondialdehyde), and nitric oxide (NO). On the other hand, it significantly (p ≤ 0.05) decreased levels of reduced glutathione (GSH) in the liver, kidney, and brain. The activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) in the liver, kidney, and brain tissues were also reduced. HS and DS supplementation prevented lipid peroxidation, normalized the serum parameters altered by AA, and enhanced the tissue concentrations and activities of antioxidant biomarkers. It could be concluded that HS and DS have potent protective effects against oxidative stress, lipid peroxidation, and DNA damage induced by AA toxicity in rats.