The relationship between N-acetylcysteine, hyperbaric oxygen, and inflammation in a rat model of acetaminophen-induced nephrotoxicity

Nephroprotective effects of hyperbaric oxygen therapy in murine models of acute kidney injury: A systematic review and meta-analysis

AIMS

Acute kidney injury (AKI) is a life-threatening condition marked by sudden kidney function loss and azotemia. While its management is limited to supportive care, the effects of hyperbaric oxygen therapy (HBO) on AKI remain a subject of conflicting animal research. This study aimed to systematically review and meta-analyze HBO's effects on renal function biomarkers serum creatinine (SCr) and blood urea nitrogen (BUN) in murine AKI models, also exploring tissue-level nephroprotection.

MAIN METHODS

The PUBMED, SciELO, and LILACS databases were searched until September 5, 2024. Effect sizes of HBO on SCr and BUN levels were expressed as standardized mean difference (SMD) alongside 95 % confidence interval (CI), calculated by random-effects model. Extracted data also included murine specie/strain, HBO parameters, AKI induction method (toxic, ischemic, others), and histological findings. Study quality and publication bias were respectively assessed using the CAMARADES checklist and Egger's test. This review adhered to PRISMA guidelines and was registered in PROSPERO (CRD42022369804).

KEY FINDINGS

Data synthesis from 21 studies demonstrates that HBO effectively reduces azotemia in AKI-affected animals (SCr's SMD = -1.69, 95 % CI = -2.38 to -0.99, P < 0.001; BUN's SMD = -1.51, 95 % CI = -2.32 to -0.71, P < 0.001) while mitigating histological damage. Subgroup analyses indicate that HBO particularly benefits ischemic and other AKI types (P < 0.05). In contrast, data from toxic AKI models were inconclusive due to insufficient statistical power (P > 0.05, 1-β < 30 %).

SIGNIFICANCE

This meta-analysis provides compelling evidence supporting the adjunctive use of HBO in AKI management.

Cinnamon Oil Alleviates Acetaminophen-Induced Uterine Toxicity in Rats by Abrogation of Oxidative Stress, Apoptosis, and Inflammation

Paracetamol, or acetaminophen (APAP), is one of the first-line medications that is used for fever and pain. However, APAP can induce uterine toxicity when overused. The mode of action of APAP toxicity is due to the production of free radicals. The main goal of our study is to determine uterine toxicity from APAP overdose and the antioxidative activity of cinnamon oil (CO) in female rats. The effect of different doses of CO (50-200 mg/kg b.w.) was assessed in the uterus toxicity induced by APAP. Additionally, the imbalance in oxidative parameters, interleukins, and caspases was evaluated for the protective effects of CO. A single dose of APAP (2 g/kg b.w.) resulted in uterus toxicity, indicated by a significant increase in the level of lipid peroxidation (LPO), inflammatory interleukins cytokines (IL-1 and 6), expression of caspases 3 and 9, and a marked change in uterus tissue architecture evaluated by histopathology. Co-treatment of CO resulted in a significant amelioration of all the parameters such as LPO, interleukins IL-1β, IL-6, caspases 3 and 9 expression, and distortion of tissue architecture in a dose-dependent manner. Therefore, we can conclude that APAP-induced uterine injury due to oxidative stress can be restored by co-treatment with cinnamon oil (CO).

Renoprotective effects of cinnamon oil against APAP-Induced nephrotoxicity by ameliorating oxidative stress, apoptosis and inflammation in rats

Acetaminophen (APAP) is used as a primary medication in relieving moderate pain and fever. However, APAP is associated with toxic effects in renal tissue that appear because of its free radicals property. The principle goal of the present work is to assess the kidney damage by APAP and its restore antioxidative property of cinnamon oil (CO). Animals were distributed into six animals each in six groups. Rats were administered with three varying doses of CO from 50 to 200 mg/kg b.w. respectively and only a single dose of APAP. APAP induced an alteration in serum biochemical markers, imbalance in oxidative parameters, morphological changes in kidney tissue along with increased interleukins cytokines (IL-1β & 6) and caspase (3, 9) levels. CO administration significantly ameliorates all the parameters and histopathological changes were restored. Moreover, it also restored the activities of antioxidative enzymes. Our work proved that an variance of oxidative markers in the kidney by APAP is ameliorated by CO in rats. Thus, CO could be used in reducing APAP-induced nephrotoxicity.

Effects of hyperbaric oxygen therapy on the expression levels of the inflammatory factors interleukin-12p40, macrophage inflammatory protein-1β, platelet-derived growth factor-BB, and interleukin-1 receptor antagonist in keloids

BACKGROUND

Our study aimed to screen and explore the expression of inflammatory factors in keloid patients and to investigate how hyperbaric oxygen (HBO) therapy affects the expression levels of interleukin-12p40 (IL-12p40), macrophage inflammatory protein-1β (MIP-1β), platelet-derived growth factor-BB (PDGF-BB), and interleukin-1 receptor antagonist (IL-1Ra).

OBJECTIVE

30 patients were randomly selected and divided into the following 3 groups: keloid samples from keloid patients treated with HBO therapy (A), keloid samples from keloid patients treated without HBO therapy (B), and normal control skin samples derived from individuals who had no clear scarring (C). Each group included 10 samples.

METHODS

Inflammatory factors in the keloid tissues were measured with the MILLIPLEX multiplexed Luminex system. Hematoxylin and eosin staining, immunohistochemical staining, and Western blotting were used to observe the morphological differences in different tissues and the expression levels.

RESULTS

The expression levels of inflammatory mediators, including IL-12p40, MIP-1β, PDGF-BB, and IL-1Ra, in keloid tissues were significantly different from those in samples of normal skin. Hematoxylin and eosin staining showed significantly greater inflammatory infiltration in keloid tissue. Significantly different expression levels were observed in group A, B, and C.

CONCLUSION

Significantly altered levels of inflammatory factors in the samples from keloid patients were observed, suggesting that formation of a keloid is potentially related to inflammatory responses. HBO therapy could significantly affect the expression levels of IL-12p40, MIP-1β, PDGF-BB, and IL-1Ra, indicating that the effects of HBO therapy are associated with the attenuation of inflammatory responses.

What a Nephrologist Needs to Know About Acute Liver Failure

Although relatively rare in the United States, acute liver failure (ALF) is associated with very high rates of morbidity and mortality. A leading cause of morbidity and mortality is cerebral edema and intracranial hypertension. Hypothermia, osmotic diuretics, and hyperosmolar therapy are commonly used to manage these complications; however, when these are ineffective, renal replacement therapy may be needed for volume management. Acute kidney injury is a common complication of ALF and may arise from a number of etiologies, including hepatorenal syndrome and acute tubular necrosis. Acute kidney injury is most common in patients who develop ALF because of acetaminophen toxicity or ischemia. With regard to renal replacement therapy, we will review specific considerations relevant to the management of the patient with ALF.

Acetaminophen induces JNK/p38 signaling and activates the caspase-9-3-dependent cell death pathway in human mesenchymal stem cells

Acetaminophen (APAP) is a widely used analgesic and antipyretic drug. Generally, the therapeutic dose of APAP is clinically safe, however, high doses of APAP can cause acute liver and kidney injury. Therefore, the majority of previous studies have focussed on elucidating the mechanisms of APAP-induced hepatotoxicity and nephrotoxicity, in addition to examining ways to treat these conditions in clinical cases. However, few studies have reported APAP-induced intoxication in human stem cells. Stem cells are important in cell proliferation, differentiation and repair during human development, particularly during fetal and child development. At present, whether APAP causes cytotoxic effects in human stem cells remains to be elucidated, therefore, the present study aimed to investigate the cellular effects of APAP treatment in human stem cells. The results of the present study revealed that high-dose APAP induced more marked cytotoxic effects in human mesenchymal stem cells (hMSCs) than in renal tubular cells. In addition, increased levels of hydrogen peroxide (H2O2), phosphorylation of c-Jun N-terminal kinase and p38, and activation of caspase-9/-3 cascade were observed in the APAP-treated hMSCs. By contrast, antioxidants, including vitamin C reduced APAP-induced augmentations in H2O2 levels, but did not inhibit the APAP-induced cytotoxic effects in the hMSCs. These results suggested that high doses of APAP may cause serious damage towards hMSCs.

Toll-like receptor 4 blocker as potential therapy for acetaminophen-induced organ failure in mice

Acetaminophen (APAP, 4-hydroxyacetanilide) is the most common cause of acute liver failure in the United States. In addition to exhibiting hepatotoxicity, APAP exerts a nephrotoxic effect may be independent of the induced liver damage. Toll-like receptors (TLRs) have been suggested as a potential class of novel therapeutic targets. The aim of the present study was to investigate the potential of the TLR-4 blocker TAK-242 in the prevention of APAP-induced hepato-renal failure. Four groups of C57BL mice were studied: Vehicle-treated/control (VEH), APAP-treated (APAP), N-acetyl cysteine (NAC)-pretreated plus APAP (APAP + NAC) and TAK-242-pretreated plus APAP (APAP + TAK) groups. Mice were clinically assessed then perfused 4 h later. Liver and kidney tissues were collected and examined histologically using basic hematoxylin and eosin staining to detect signs of necrosis and inflammation. Plasma samples were collected to measure the levels of alanine transaminase, aspartate transaminase and serum creatinine. In addition, liver and kidney tissues were assayed to determine the levels of reduced glutathione. The results of the present study indicate the potential role of TLR-4 in APAP-induced organ toxicity. In the APAP + TAK and APAP + NAC groups, histopathological examination indicated that pretreatment with TAK-242 or NAC afforded protection against APAP-induced injury. However, this protective effect was more clinically evident in the APAP + TAK group compared with the APAP + NAC group. The various biochemical parameters (serum enzymes and reduced glutathione) revealed no significant protection in either of the pretreated groups. Therefore, the present study indicated that the TLR-4 blocker had protective effects against acute APAP toxicity in liver and kidney tissues. These effects were identified clinically, histologically and biochemically. Furthermore, the TLR-4 blocker TAK-242 exhibited antioxidant properties in addition to anti-inflammatory effects.

Effects of dexpanthenol and N-acetylcysteine pretreatment in rats before renal ischemia/reperfusion injury

BACKGROUND

We investigated the anti-inflammatory and protective effects of concomitant use of dexpanthenol (DXP) and N-acetylcysteine (NAC) induced ischemia/reperfusion (I/R) injury of kidney.

METHODS

Forty rats were randomly divided into 5 groups. In all groups except for Group 1(Sham), renal arteries bilaterally occluded with vascular clamp for IR injury. Group 1(Sham), received a single dose of 10 mL/kg isotonic saline daily by intraperitoneal (IP) injection for three days. Group 2(IR), received a single dose of 10 mL/kg isotonic saline daily by IP injection for three days. Group 3(IR + NAC), received 300 mg/kg NAC daily by IP injection for three days. Group 4(IR + DXP), received 500 mg/kg DXP daily by IP injection for three days. Group 5(IR + NAC + DXP), received 500 mg/kg DXP and 300 mg/kg NAC daily by IP injection for three days. Serum urea (BUN), creatinine (Cr) and neutrophil gelatinase-associated lipocalin (NGAL, lipocalin 2, siderocalin) levels were measured as kidney function tests. TNF-α levels were measured as inflammatory marker. Tissue sections were evaluated histopathologically under light microscopy.

RESULTS

IR + NAC + DXP group received both NAC and DXP before induction of renal I/R and as the biochemical and histopathological data revealed the results of the IR + NAC + DXP group and sham group were similar. Biochemically and histopathologically, combined use of NAC and DXP has better results when each of them used alone.

CONCLUSION

We concluded that concomitant use of DXP and NAC plays a major role against I/R injury and may be useful in acute treatment of I/R induced renal failure.

Dual role of acetaminophen in promoting hepatoma cell apoptosis and kidney fibroblast proliferation

Acetaminophen (APAP), is a safe analgesic and antipyretic drug at therapeutic dose, and is widely used in the clinic. However, high doses of APAP can induce hepatotoxicity and nephrotoxicity. Most studies have focused on high‑dose APAP‑induced acute liver and kidney injury. So far, few studies have investigated the effects of the therapeutic dose (1/10 of the high dose) or of the low dose (1/100 of the high dose) of APAP on the cells. The aim of this study was to investigate the cellular effects of therapeutic- or low‑dose APAP treatment on hepatoma cells and kidney fibroblasts. As expected, high‑dose APAP treatment inhibited while therapeutic and low‑dose treatment did not inhibit cell survival of kidney tubular epithelial cells. In addition, therapeutic-dose treatment induced an increase in the H2O2 level, activated the caspase‑9/‑3 cascade, and induced cell apoptosis of hepatoma cells. Notably, APAP promoted fibroblast proliferation, even at low doses. This study demonstrates that different cellular effects are exerted upon treatment with different APAP concentrations. Our results indicate that treatment with the therapeutic dose of APAP may exert an antitumor activity on hepatoma, while low‑dose treatment may be harmful for patients with fibrosis, since it may cause proliferation of fibroblasts.