Inorganic phosphate-induced cytotoxicity

The prognostic value of the phosphate-to-albumin ratio in patients with OHCA: A multicenter observational study

PURPOSE

In patients with out-of-hospital cardiac arrest (OHCA), early and accurate outcome prediction is crucial for making treatment decisions and informing their relatives. A previous study reported an association between high phosphate levels and unfavorable neurological outcomes after return of spontaneous circulation (ROSC); however, its prognostic value was insufficient when used independently. Therefore, this study aimed to validate the usefulness of the phosphate-to-albumin ratio (PAR) in predicting neurological outcomes and in-hospital mortality by incorporating albumin, another known prognostic indicator.

MATERIALS AND METHODS

This multicenter observational study included adult OHCA survivors from October 2015 to June 2021. The primary endpoint was an unfavorable neurological outcome at hospital discharge, defined as a cerebral performance category score of 3-5. The in-hospital mortality rates were also evaluated.

RESULTS

Of the 2397 adult OHCA survivors, PAR differed significantly between the unfavorable and favorable neurological outcome groups, as well as between the non-survival and survival to hospital discharge groups (2.4 vs 1.4, 2.5 vs 1.6, respectively). The area under the receiver operating characteristic curve (AUROC) value of the PAR for predicting unfavorable neurological outcome was 0.81 (95% confidence interval [CI], 0.79-0.83), and the AUROC value for predicting in-hospital mortality was 0.76 (95% CI, 0.74-0.78). In multivariable analysis, the PAR was independently associated with unfavorable neurological outcome (odds ratio [OR] 1.30, 95% CI 1.15-1.37; p < 0.001) and in-hospital mortality (OR 1.24, 95% CI 1.12-1.38; p < 0.001).

CONCLUSION

The PAR is a readily obtainable and independent prognostic indicator for patients with ROSC after OHCA, helping healthcare providers in predicting outcomes.

Beneficial or harmful: Time-dependent hormesis induced by typical disinfectants and their mixtures with toxicological interaction

Disinfectants and their mixtures can induce hormesis. However, how the mixture hormesis is related to those of components and the interactions in disinfectant mixtures remain unclear. In this paper, the luminescence inhibition toxicities of chlorinated sodium phosphate (CSP), dodecyl dimethyl benzyl ammonium bromide (DOB), dodecyl dimethyl benzyl ammonium chloride (DOC), ethanol (EtOH), glutaraldehyde (GLA), hydrogen peroxide (H2O2), isopropyl alcohol (IPA), n-propanol (NPA), and 20 mixture rays in four mixture systems (EtOH-H2O2, DOB-H2O2, DOC-EtOH, and EtOH-IPA-NPA) containing at least one component showing hormesis to Vibrio qinghaiensis sp.-Q67 (Q67) were determined at 0.25, 3, 6, 9, and 12 h. The synergism-antagonism heatmap based on independent action model (noted as SAHmapIA) was developed to systematically evaluate the interactions in various mixtures. It was shown that five disinfectants (CSP, EtOH, H2O2, NPA, and IPA) and 17 mixture rays exhibited time-dependent hormesis. The hormetic component was responsible for the hormesis of the mixture rays. Most mixture rays showed low- concentration/dose additive action and high-concentration/dose synergism at different time. This study further exemplified the interrelationship between the hormesis in the mixtures and their components and implied the need to pay attention to the time-dependent hormesis and interactions induced by the disinfectants.

ANALYSIS OF THE RELATIONSHIP BETWEEN EARLY SERUM PHOSPHATE LEVELS AND SHORT-TERM MORTALITY IN SEPTIC PATIENTS: A RETROSPECTIVE STUDY BASED ON MIMIC-IV

ABSTRACT

Objective: The aim of the study is to explore the impact of early serum phosphate levels on the prognosis of critically ill patients with sepsis. Methods: In this retrospective large cohort study, data of patients with sepsis were obtained from the Medical Information Mart for Intensive Care IV database. Patients were retrospectively divided into a control group and three study groups according to their daily serum phosphate levels within 2 days of intensive care unit (ICU) admission. A Cox regression model was used to evaluate the association between serum phosphate levels and 28-day morbidity. Results: This study included 9,691 patients diagnosed with sepsis. During the first 2 days of ICU admission, patients with hyperphosphatemia in either of the 2 days had higher 28-day mortality, while patients in the hypophosphatemia group had lower 28-day mortality (first day, 32.9% vs. 16.3%; second day, 36.3% vs. 14.7%). After adjusting for potential confounders, hyperphosphatemia was significantly associated with 28-day mortality; however, only hypophosphatemia on the second day was independently associated with reduced 28-day mortality. After stratification in the hypophosphatemia group, subgroup analysis showed that only the association between the mild hypophosphatemia group and 28-day mortality reached statistical significance (hazard ratio = 0.76, 95% CI = 0.65-0.89, P = 0.001). Conclusions: Mild hypophosphatemia might improve the short-term prognosis of patients with sepsis, and hyperphosphatemia is an independent risk factor for the outcomes of septic patients. After ICU admission, the serum phosphate levels on the second day had a better independent correlation with 28-day mortality, which prompted us to reconsider the optimal timing of phosphate evaluation.

Nutritional deficiencies that may predispose to long COVID

Multiple nutritional deficiencies (MND) confound studies designed to assess the role of a single nutrient in contributing to the initiation and progression of disease states. Despite the perception of many healthcare practitioners, up to 25% of Americans are deficient in five-or-more essential nutrients. Stress associated with the COVID-19 pandemic further increases the prevalence of deficiency states. Viral infections compete for crucial nutrients with immune cells. Viral replication and proliferation of immunocompetent cells critical to the host response require these essential nutrients, including zinc. Clinical studies have linked levels of more than 22 different dietary components to the likelihood of COVID-19 infection and the severity of the disease. People at higher risk of infection due to MND are also more likely to have long-term sequelae, known as Long COVID.

Acute low-dose phosphate disrupts glycerophospholipid metabolism and induces stress in juvenile turbot (Scophthalmus maximus)

Phosphate, as the main nutrient factor of lake eutrophication brought by pollutants discharged from agriculture and industry, is always considered to be a low-toxicity substance to aquatic animals. But the toxicity mechanism is unclear, and published information is limited. In this study, a 96 h acute stress experiment was conducted on juvenile turbot (Scophthalmus maximus) with 0, 10, and 60 mg/L phosphate solutions. Metabonomic analysis revealed that low-dose phosphate (10 mg/L) disrupted glycerophospholipid, purine, and glycolipid metabolism, as well as the tricarboxylic acid (TCA) cycle in juveniles, even at 96 h of stress, which may lead to cell structure damage and signal recognition disorder between cells. Upregulated key genes in the main glycerophospholipid metabolic pathways, which matched the results of the metabolomic study, were detected. Furthermore, low-dose phosphate (10 mg/L) induced oxidative stress and immunotoxicity in fish, resulting in the raising of relevant genes expression such as cat and sod in liver and kidney. In addition, all phosphate-treated groups had induced lesions on gill tissue, as evidenced by pathological observations. In this study on toxic effects on and mechanism of phosphate in aquatic animals using metabolomics, gene expression, and histopathology, we confirm that acute low-dose phosphate could disrupt glycerophospholipid metabolism and induce stress in juvenile turbot. This can provide advice on the amount of phosphate accumulation for marine fish farming and on protecting species diversity and marine ecosystem from the point of view of phosphate toxicity to marine animals.

NRF2 Pathway Activation Attenuates Aging-Related Renal Phenotypes due to α-Klotho Deficiency

Oxidative stress is one of the major causes of the age-related functional decline in cells and tissues. The KEAP1-NRF2 system plays a central role in the regulation of redox balance, and NRF2 activation exerts antiaging effects by controlling oxidative stress in aged tissues. α-Klotho was identified as an aging suppressor protein based on the premature aging phenotypes of its mutant mice, and its expression is known to gradually decrease during aging. Because α-Klotho has been shown to possess antioxidant function, aging-related phenotypes of α-Klotho mutant mice seem to be attributable to increased oxidative stress at least in part. To examine whether NRF2 activation antagonizes aging-related phenotypes caused by α-Klotho deficiency, we crossed α-Klotho-deficient (Kl–/–) mice with a Keap1-knockdown background, in which the NRF2 pathway is constitutively activated in the whole body. NRF2 pathway activation in Kl–/– mice extended the lifespan and dramatically improved aging-related renal phenotypes. With elevated expression of antioxidant genes accompanied by an oxidative stress decrease, the antioxidant effects of NRF2 seem to make a major contribution to the attenuation of aging-related renal phenotypes of Kl–/– mice. Thus, NRF2 is expected to exert an antiaging function by partly compensating for the functional decline of α-Klotho during physiological aging.