Search Results (36)

Background: Sepsis-induced acute lung injury (ALI) is a serious disease constituting a heavy burden on society due to high mortality and morbidity. Inflammation and oxidative stress constitute key pathological mechanisms in ALI caused by sepsis. LL-37 can improve the survival of septic mice. Nevertheless, its function and underlying mechanism in sepsis-evoked ALI is elusive. Methods: The human A549 alveolar epithelial cell line was treated with LL-37 or ZBP1 recombinant vector under LPS exposure. Then, the effects on cell oxidative stress injury, inflammatory response, and autophagy were analyzed. RNA-seq analysis was performed to detect the differentially expressed genes (DEGs) between the LPS and LPS/LL-37 groups. Furthermore, the effects of LL-37 on cecal ligation and the puncture (CLP)-constructed ALI model were explored. Results: LL-37 attenuated LPS-evoked oxidative injury in human alveolar epithelial cells by increasing cell viability and suppressing ROS, malondialdehyde, and lactate dehydrogenase levels and apoptosis. Moreover, LPS-induced releases of pro-inflammatory IL-18, TNF-α, and IL-1β were suppressed by LL-37. Furthermore, LPS’s impairment of autophagy was reversed by LL-37. RNA-seq analysis substantiated 1350 differentially expressed genes between the LPS and LPS/LL-37 groups. Among them was ZBP1, a significantly down-regulated gene with the largest fold change. Moreover, LL-37 suppressed LPS-increased ZBP1 expression. Importantly, ZBP1 elevation restrained LL-37-induced autophagy in LPS-treated cells and abrogated LL-37-mediated protection against LPS-evoked oxidative injury and inflammation. LL-37 ameliorated abnormal histopathological changes, tissue edema, the lung injury score, oxygenation index (PaO2/FiO2), and glycemia contents in the CLP-constructed ALI model, which were offset through ZBP1 elevation via its activator CBL0137. Additionally, LL-37 suppressed inflammation and oxidative stress in lung tissues, concomitant with autophagy elevation and ZBP1 down-regulation. Conclusions: LL-37 may alleviate the progression of sepsis-evoked ALI by attenuating pulmonary epithelial cell oxidative injury and inflammatory response via ZBP1-mediated autophagy activation, indicating a promising approach for the therapy of ALI patients. Full article

Patients with sepsis often receive mechanical ventilation (MV). Continued use of MV may increase overdistention in the lungs, inflammatory mediator production, and inflammatory cell recruitment, eventually causing ventilator-induced lung injury (VILI). Endoplasmic reticulum (ER) stress caused by MV, oxidative stress, and sepsis results in dissociation of GRP78 from transmembrane proteins (PERK, IRE1α, and ATF6) and generates abundant incorrect protein structures. Phosphoinositide 3-kinase-γ (PI3K-γ) has been demonstrated to modulate ER stress associated with sepsis and acute lung injury (ALI). However, the regulatory mechanisms by which ER stress is involved in VILI remain unclear. In this study, MV was hypothesized to augment lung injury and induce ER stress through the PI3K-γ pathway, regardless of endotoxemia. Wild-type or PI3K-γ-deficient C57BL/6 mice were exposed to 30 mL/kg tidal volume of MV with or without endotoxemia for 5 h. The control group comprised nonventilated mice. MV with endotoxemia increased microvascular permeability, lung edema, interleukin-6 and metalloproteinase-9 production, oxidative loads, ER stress biomarkers (GRP78, IRE-1α, PERK), morphological rearrangement, PI3K-γ expression, and bronchial epithelial apoptosis in rodent lungs. The increase in lung injury was substantially reduced in PI3K-γ-deficient mice and in mice administered 4-phenylbutyric acid. In conclusion, MV-augmented ALI after endotoxemia partially depends on the PI3K-γ pathway. Full article

Sepsis is a clinical condition causing tissue damage as a result of infection and an exaggerated immune response. Sepsis causes 11 million deaths annually, a third of which are associated with acute lung injury (ALI). Rapid and effective treatment is crucial to improve survival rates. Punica granatum (pomegranate) is rich in polyphenols and demonstrates strong antioxidant activity, while amifostine acts as a free radical scavenger. This study aimed to investigate the antioxidant and anti-inflammatory effects of P. granatum peel extract (PGPE) and amifostine in sepsis-related ALI. Experimental groups included Control, CLP (cecal ligation and puncture-induced sepsis), Amf (200 mg/kg amifostine, intraperitoneally), and PGPE250, and PGPE500 (250 and 500 mg/kg PGPE via oral gavage, respectively). Thiobarbituric acid reactive substances (TBARS), total thiol (TT), tumor necrosis factor-alpha (TNF-α) levels, and metalloproteinases 2 and 9 (MMP-2 and MMP-9) were assessed in the lung tissue. Biochemical analysis demonstrated that TBARS and TNF-α levels significantly decreased in both the PGPE and amifostine treatment groups compared to the CLP group, while TT levels showed notable improvement. Histopathological evaluation revealed reduced MMP-2 and MMP-9 immunopositivity in the PGPE250 and PGPE500 groups. These findings highlight the lung-protective properties of PGPE, underscoring its potential as a therapeutic agent for sepsis-induced acute lung injury. Full article

Acute lung injury (ALI) is induced by pneumonia, sepsis and other conditions. The disease characteristics include severe lung inflammation, in which various cells, such as epithelial cells, macrophages, and neutrophils, play a pivotal role. Corticosteroids and antibiotics are used to treat ALI; however, they may have side effects. Cumulative data confirm that traditional herbal medicines exert therapeutic effects against endotoxin-induced inflammatory responses in both in vitro and in vivo ALI studies. This review briefly describes the anti-ALI effects of medicinal herbal extracts (MHEs) and their molecular mechanisms, especially focusing on Toll-like receptor 4/nuclear factor kappa B cell pathways, with a brief summary of in vitro and in vivo ALI experimental models. Thus, the present review highlights the excellent potential of MHEs for ALI therapy and prevention and may also be useful for the establishment of in vitro and in vivo ALI models. Full article

Sepsis is characterized by multiple organ dysfunction, which is now accepted to be due to oxidative damage. The lung is the first organ exposed to this damage, and its injury is one of the leading causes of death. Therefore, many pharmacological strategies are employed to attenuate sepsis. This study aimed to evaluate the in silico and in vitro antibacterial activity of Cicer arietinum extract (CAE) against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa and the in vivo modulatory effect of CAE against sepsis induced by cecal ligation and puncture (CLP) in rats. This study identified seven bioactive components in Cicer arietinum extract, revealing promising interactions between these components and Staphylococcus aureus-PBP2a and Pseudomonas aeruginosa-PBP3 proteins, highlighting their potential as novel antibacterial agents. After ensuring the bactericidal ability of CAE against Staphylococcus aureus and Pseudomonas aeruginosa, an in vivo study was performed. Twenty-four rats were divided into sham-operated rats, CLP-septic rats, CLP rats treated with CAE (500 mg/kg b.wt), and CLP rats treated with hydrocortisone (25 mg/ kg b.wt). CAE was administered orally for 3 days post-operation, and animals were euthanized on the fourth day. Another twenty-four rats were used to study survival for 5 days. This study revealed that CAE, like hydrocortisone, can rescue CLP rats from death by suppressing lung procalcitonin (PCT) and MDA and enhancing SOD, CAT, and GSH levels significantly, as compared with the CLP group. The histopathological results were parallel with the biochemical results since the CLP rats treated with CAE had lower histological/inflammatory scores in the lung like hydrocortisone. The beneficial role of CAE may result from its antibacterial and antioxidant activities, and CAE can be considered as a lung antiseptic extract. This study provides a novel treatment for sepsis-induced ALI. However, the beneficial impact of CAE needs extensive study to obtain evidence. Full article

Acute lung injury (ALI) and its most severe form, acute respiratory distress syndrome (ARDS), are pulmonary conditions that cause significant morbidity and mortality. The common etiologies of these conditions include pneumonia, pulmonary contusion, fat embolism, smoke inhalation, sepsis, shock, and acute pancreatitis. Inflammation, oxidative stress, apoptosis, and autophagy are key pathophysiological mechanisms underlying ALI. Hydrogen sulfide (H₂S) and sulfur dioxide (SO₂) are sulfur-containing gas signaling molecules that can mitigate these pathogenic processes by modulating various signaling pathways, such as toll-like receptor 4 (TLR4)/nod-like receptor protein 3 (NLRP3), extracellular signal-regulating protein kinase 1/2 (ERK1/2), mitogen-activated protein kinase (MAPK), phosphatidyl inositol 3 kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR), and nuclear factor kappa B (NF-κB), thereby conferring protection against ALI. Given the limited clinical effectiveness of prevailing ALI treatments, investigation of the modulation of sulfur-containing gas signaling molecules (H₂S and SO₂) in ALI is imperative. This article presents an overview of the regulatory pathways of sulfur-containing gas signaling molecules in ALI animal models induced by various stimuli, such as lipopolysaccharide, gas inhalation, oleic acid, and ischemia-reperfusion. Furthermore, this study explored the therapeutic prospects of diverse H₂S and SO₂ donors for ALI, stemming from diverse etiologies. The aim of the present study was to establish a theoretical framework, in order to promote the new treatment of ALI. Full article

Sepsis-induced acute lung injury (ALI), characterized by widespread lung dysfunction, is associated with significant morbidity and mortality due to the lack of effective pharmacological treatments available clinically. Small-molecule compounds derived from natural products represent an innovative source and have demonstrated therapeutic potential against sepsis-induced ALI. These natural small molecules may provide a promising alternative treatment option for sepsis-induced ALI. This review aims to summarize the pathogenesis of sepsis and potential therapeutic targets. It assembles critical updates (from 2014 to 2024) on natural small molecules with therapeutic potential against sepsis-induced ALI, detailing their sources, structures, effects, and mechanisms of action. Full article

Sepsis-induced ALI is marked by physiological, pathological, and biochemical irregularities caused by infection. Growth differentiation factor 3 (GDF3) is closely associated with the inflammatory response. Accumulating evidence has demonstrated a close relationship between GDF3 expression and the severity and prognosis of sepsis. However, the precise mechanism by which GDF3 protects against ALI induced by sepsis is still unclear. Following the intravenous administration of GDF3 in this research, we noted a rise in the survival rate, a decrease in the severity of histopathological damage as evaluated through HE staining, a decline in the count of inflammatory cells in bronchoalveolar lavage fluid (BALF), a reduction in the ratio of lung wet/dry (W/D) weight, and a noteworthy decrease in the levels of pro-inflammatory cytokines in both serum and BALF when compared to septic mice who underwent cecal ligation and puncture (CLP). These collective findings unequivocally indicate the protective effects of GDF3 against sepsis-induced ALI. In addition, the GDF3 group showed a significant reduction in the mRNA expression of Caspase-1 and NLRP3 when compared to the CLP group. Following this, we performed in vitro tests to confirm these discoveries and obtained comparable outcomes, wherein the administration of GDF3 notably decreased the levels of Caspase-1 and NLRP3 mRNA and protein in macrophages in comparison to the LPS group. Furthermore, GDF3 exhibited the capacity to reduce the secretion of inflammatory molecules from macrophages. By illuminating the mechanism by which GDF 3 regulates macrophages, this offers a theoretical basis for preventing and treating sepsis-induced ALI. Full article

Earlier studies from our lab identified endoplasmic reticulum (ER) chaperone BiP/GRP78, an important component of MAM, to be a novel determinant of endothelial cell (EC) dysfunction associated with acute lung injury (ALI). Sigma1R (Sig1R) is another unique ER receptor chaperone that has been identified to associate with BiP/GRP78 at the MAM and is known to be a pluripotent modulator of cellular homeostasis. However, it is unclear if Sig1R also plays a role in regulating the EC inflammation and permeability associated with ALI. Our data using human pulmonary artery endothelial cells (HPAECs) showed that siRNA-mediated knockdown of Sig1R potentiated LPS-induced the expression of proinflammatory molecules ICAM-1, VCAM-1 and IL-8. Consistent with this, Sig1R agonist, PRE-084, known to activate Sig1R by inducing its dissociation from BiP/GRP78, blunted the above response. Notably, PRE-084 failed to blunt LPS-induced inflammatory responses in Sig1R-depleted cells, confirming that the effect of PRE-084 is driven by Sig1R. Furthermore, Sig1R antagonist, NE-100, known to inactivate Sig1R by blocking its dissociation from BiP/GRP78, failed to block LPS-induced inflammatory responses, establishing that dissociation from BiP/GRP78 is required for Sig1R to exert its anti-inflammatory action. Unlike Sig1R, the siRNA-mediated knockdown or Subtilase AB-mediated inactivation of BiP/GRP78 protected against LPS-induced EC inflammation. Interestingly, the protective effect of BiP/GRP78 knockdown or inactivation was abolished in cells that were depleted of Sig1R, confirming that BiP/GRP78 knockdown/inactivation-mediated suppression of EC inflammation is mediated via Sig1R. In view of these findings, we determined the in vivo relevance of Sig1R in a mouse model of sepsis-induced ALI. The intraperitoneal injection of PRE-084 mitigated sepsis-induced ALI, as evidenced by a decrease in ICAM-1, IL-6 levels, lung PMN infiltration, and lung vascular leakage. Together, these data evidence a protective role of Sig1R against endothelial dysfunction associated with ALI and identify it as a viable target in terms of controlling ALI in sepsis. Full article

Sepsis, a leading global cause of morbidity and mortality, involves multiple organ dysfunction syndromes driven by free radical-mediated processes. Uncontrolled inflammation in early sepsis stages can lead to acute lung injury (ALI). Activated leukocytes generate reactive oxygen species, contributing to sepsis development. Gallic acid, a phenolic compound, is known for its antimicrobial properties. This study aims to observe gallic acid’s protective and restorative effect on the lungs in an experimental sepsis model. Male Wistar albino rats were subjected to a feces intraperitoneal injection procedure (FIP) to induce sepsis. Four groups were formed: normal control, FIP alone, FIP with saline, and FIP with gallic acid. Gallic acid was administered intraperitoneally at 20 mg/kg/day. Blood samples were collected for biochemical analysis, and computed tomography assessed lung tissue histopathologically and radiologically. Gallic acid significantly decreased malondialdehyde, IL-6, IL-1β, TNF-α, CRP levels, oxidative stress, and inflammation indicators. Lactic acid levels decreased, suggesting improved tissue oxygenation. Histopathological examinations revealed reduced lung damage in the gallic-acid-treated group. Computed tomography confirmed lower lung density, indicating less severe inflammation. Arterial blood gas analysis demonstrated improved oxygenation in gallic-acid-treated rats. Gallic acid exhibited anti-inflammatory and antioxidant effects, reducing markers of systemic inflammation and oxidative stress. The findings support its potential to protect against ALI during sepsis. Comparable studies underline gallic acid’s anti-inflammatory properties in different tissues. Early administration of gallic acid in sepsis models demonstrated protective effects against ALI, emphasizing its potential as an adjunct therapy to mitigate adverse outcomes. The study proposes gallic acid to reduce mortality rates and decrease the need for mechanical ventilation during sepsis-induced ALI. Full article

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS), triggered by various pathogenic factors inside and outside the lungs, leads to diffuse lung injury and can result in respiratory failure and death, which are typical clinical critical emergencies. Severe acute pancreatitis (SAP), which has a poor clinical prognosis, is one of the most common diseases that induces ARDS. When SAP causes the body to produce a storm of inflammatory factors and even causes sepsis, clinicians will face a two-way choice between anti-inflammatory and anti-infection objectives while considering the damaged intestinal barrier and respiratory failure, which undoubtedly increases the difficulty of the diagnosis and treatment of SAP-ALI/ARDS. For a long time, many studies have been devoted to applying glucocorticoids (GCs) to control the inflammatory response and prevent and treat sepsis and ALI/ARDS. However, the specific mechanism is not precise, the clinical efficacy is uneven, and the corresponding side effects are endless. This review discusses the mechanism of action, current clinical application status, effectiveness assessment, and side effects of GCs in the treatment of ALI/ARDS (especially the subtype caused by SAP). Full article

Sepsis is a severe medical condition distinguished by immune systematic dysfunction and multiple organic injury, or even failure, resulting from an acute systemic inflammatory response. Acute liver injury (ALI) could be considered as a notable inflammatory outcome of sepsis. Studies have demonstrated the essential roles played by long non-coding RNAs (lncRNAs) in mediating the processes of various diseases, including their ability to engage in interactions with microRNAs (miRNAs) as complexes of competing endogenous RNA (ceRNA) to modulate signaling pathways. In this study, a newly discovered lncRNA, named 220, was identified to function in regulating autophagy and apoptosis in Kupffer cells treated with lipopolysaccharide (LPS). This was achieved through sponging miR-5101 as a ceRNA complex, as identified via high-throughput sequencing. The expression of 220 was found to be significantly different in the hepatic tissues of endotoxemic mice that were treated with LPS for 8 h, ultimately modulating the ALI process. Our studies have collectively demonstrated that 220 is a novel regulator that acts on LPS-induced autophagy and apoptosis in Kupffer cells, thereby mediating the ALI process induced by LPS. Furthermore, the validation of our findings using clinical databases suggests that 220 could potentially serve as a molecular target of clinical, diagnostic, and therapeutic significance in septic liver injury. Full article

Acute lung injury (ALI) is a frequent and challenging aspect of sepsis that currently lacks effective treatments. Procyanidin B2 (PB2) has anti-inflammatory and antioxidant properties. The aim of this study was to determine the effectiveness and mechanism of action of PB2 in treating sepsis-induced ALI using animal experiments. A sepsis-induced ALI mouse model was used by administering lipopolysaccharide (LPS) and then evaluating the levels of inflammatory cytokines and lung injury through measurements of cytokine levels using enzyme-linked immunosorbent assay (ELISA), Western blot and real-time PCR, as well as by the examination of relevant signaling pathways. The animal experiments showed that PB2 protected the lungs from injury caused by LPS and reduced the levels of various inflammatory cytokines in both the serum and lung tissue. Western blot analysis showed that PB2 reduced the expression of TLR4/NF-κB and increased the expression of PI3K/Akt, and also inhibited the Hippo and Rho signaling pathways. The results of the study showed that PB2 helps to treat sepsis-induced ALI by controlling cytokine storms and reducing inflammation by altering the expressions of the TLR4/NF-κB, PI3K/Akt, Hippo and Rho signaling pathways. This research provides a foundation for the further investigation of PB2’s mechanism and its potential use in treating sepsis. Full article

Enhanced heat shock protein-70 (HSP-70) expression in the lungs is associated with attenuated acute lung injury (ALI) in a sepsis model. Chronic kidney disease (CKD) significantly contributes to the poor prognosis of patients with sepsis. This study examined the relationship between sepsis-induced ALI severity and altered lung HSP-70 expression in CKD. Experimental rats underwent a sham operation (control group) or 5/6 nephrectomy (CKD group). Sepsis was induced with cecal ligation and puncture (CLP). Laboratory tests and lung harvest were performed in the control group (without CLP and after 3, 12, 24, and 72 h of CLP) and in the CKD group (without CLP and after 72 h of CLP). ALI was the most severe after 12 h of sepsis. The mean lung injury score at 72 h after sepsis was significantly higher in the CKD group than in the control group (4.38 versus 3.30, p < 0.01). Nonetheless, enhanced lung HSP-70 expression was not observed in the CKD group. This study shows that altered lung HSP-70 expression is associated with the worsening of sepsis-induced ALI in patients with CKD. Enhancing lung HSP-70 is a novel treatment target for patients with CKD and sepsis-induced ALI. Full article

Uridine metabolism is extensively reported to be involved in combating oxidative stress. Redox-imbalance-mediated ferroptosis plays a pivotal role in sepsis-induced acute lung injury (ALI). This study aims to explore the role of uridine metabolism in sepsis-induced ALI and the regulatory mechanism of uridine in ferroptosis. The Gene Expression Omnibus (GEO) datasets including lung tissues in lipopolysaccharides (LPS) -induced ALI model or human blood sample of sepsis were collected. In vivo and vitro, LPS was injected into mice or administered to THP-1 cells to generate sepsis or inflammatory models. We identified that uridine phosphorylase 1 (UPP1) was upregulated in lung tissues and septic blood samples and uridine significantly alleviated lung injury, inflammation, tissue iron level and lipid peroxidation. Nonetheless, the expression of ferroptosis biomarkers, including SLC7A11, GPX4 and HO-1, were upregulated, while lipid synthesis gene (ACSL4) expression was greatly restricted by uridine supplementation. Moreover, pretreatment of ferroptosis inducer (Erastin or Era) weakened while inhibitor (Ferrostatin-1 or Fer-1) strengthened the protective effects of uridine. Mechanistically, uridine inhibited macrophage ferroptosis by activating Nrf2 signaling pathway. In conclusion, uridine metabolism dysregulation is a novel accelerator for sepsis-induced ALI and uridine supplementation may offer a potential avenue for ameliorating sepsis-induced ALI by suppressing ferroptosis. Full article