Short Exposure to Ethanol Diminishes Caspase-1 and ASC Activation in Human HepG2 Cells In Vitro

The role of the purinergic ligand-gated ion channel 7 receptor in common digestive system cancers

The incidence of digestive malignancies has increased in recent years, including colorectal cancer (CRC), hepatocellular carcinoma (HCC) and pancreatic cancer. Advanced stages of these cancers are prone to metastasis, which seriously reduce the standard of living of patients and lead to decline in the survival rate of patients. So far there are no good specific drugs to stop this phenomenon. It is very important and urgent to find new biomarkers and therapeutic targets. Purinergic ligand-gated ion channel 7 receptor (P2X7R) is ATP-gated and nonselective ion channel receptor involved in many inflammatory processes and cancer progression. P2X7R is present in many cancer cells and promotes or inhibits cancer development through signal transduction. Studies have presented that P2X7R plays a role in the proliferation and migration of digestive system cancers, such as CRC, HCC and pancreatic cancer. Therefore, P2X7R may serve as a biomarker or therapeutic target for digestive system cancers. This paper describes the structure and function of P2X7R, and mainly reviews the research progress on the role of P2X7R in CRC, HCC and pancreatic cancer.

Ethanol causes non-communicable disease through activation of NLRP3 inflammasome: a review on mechanism of action and potential interventions

Background: Ethanol exposure has been suggested to be implicated in the initiation and progression of several non-communicable diseases (NCD), including neurological disorders, diabetes mellitus, alcoholic liver disease, gastric injury, pancreatitis, and atherosclerosis. Recent findings show that the NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome is involved in the progression of ethanol-induced NCDs.Objective: The aim of this review was to summarize the research progress on NCDs associated with the action of the NLRP3 inflammasome by ethanol and potential interventions, with a specific focus on preclinical literature.Methods: A literature search was conducted on PubMed using the keywords "[ethanol] and [NLRP3]" up until January 2023. Articles describing cases of NCDs caused by ethanol and associated with the NLRP3 inflammasome were included.Results: After removing duplicates, 35 articles were included in this review. These studies, mostly conducted in animals or in vitro, provide evidence that ethanol can contribute to the development of NCDs, such as neurological disorders, alcoholic liver disease, gastric injury, pancreatitis, and atherosclerosis, by activating the NLRP3 inflammasome. Ethanol exposure primarily triggers NLRP3 inflammasome activation by influencing the TRL/NF-κB, ROS-TXNIP-NLRP3 and P2X7 receptor (P2X7R) signaling pathways. Several natural extracts and compounds have been found to alleviate NCDs caused by ethanol consumption by inhibiting the activation of the NLRP3 inflammasome.Conclusion: Preclinical research supports a role for ethanol-induced NLRP3 inflammasome in the development of NCDs. However, the clinical relevance remains uncertain in the relative absence of clinical studies.

Biomaterials Functionalized with Inflammasome Inhibitors-Premises and Perspectives

This review aimed at searching literature for data regarding the inflammasomes' involvement in the pathogenesis of oral diseases (mainly periodontitis) and general pathologies, including approaches to control inflammasome-related pathogenic mechanisms. The inflammasomes are part of the innate immune response that activates inflammatory caspases by canonical and noncanonical pathways, to control the activity of Gasdermin D. Once an inflammasome is activated, pro-inflammatory cytokines, such as interleukins, are released. Thus, inflammasomes are involved in inflammatory, autoimmune and autoinflammatory diseases. The review also investigated novel therapies based on the use of phytochemicals and pharmaceutical substances for inhibiting inflammasome activity. Pharmaceutical substances can control the inflammasomes by three mechanisms: inhibiting the intracellular signaling pathways (Allopurinol and SS-31), blocking inflammasome components (VX-765, Emricasan and VX-740), and inhibiting cytokines mediated by the inflammasomes (Canakinumab, Anakinra and Rilonacept). Moreover, phytochemicals inhibit the inflammasomes by neutralizing reactive oxygen species. Biomaterials functionalized by the adsorption of therapeutic agents onto different nanomaterials could represent future research directions to facilitate multimodal and sequential treatment in oral pathologies.

Identification of molecular subtypes based on PANoptosis-related genes and construction of a signature for predicting the prognosis and response to immunotherapy response in hepatocellular carcinoma

Background

Previous studies have demonstrated that PANoptosis is strongly correlated with cancer immunity and progression. This study aimed to develop a PANoptosis-related signature (PANRS) to explore its potential value in predicting the prognosis and immunotherapy response of hepatocellular carcinoma (HCC).

Methods

Based on the expression of PANoptosis-related genes, three molecular subtypes were identified. To construct a signature, the differentially expressed genes between different molecular subtypes were subjected to multivariate least absolute shrinkage and selection operator Cox regression analyses. The risk scores of patients in the training set were calculated using the signature. The patients were classified into high-risk and low-risk groups based on the median risk scores. The predictive performance of the signature was evaluated using Kaplan-Meier plotter, receiving operating characteristic curves, nomogram, and calibration curve. The results were validated using external datasets. Additionally, the correlation of the signature with the immune landscape and drug sensitivity was examined. Furthermore, the effect of LPCAT1 knockdown on HCC cell behavior was verified using in vitro experiments.

Results

This study developed a PANRS. The risk score obtained by using the PANRS was an independent risk factor for the prognosis of patients with HCC and exhibited good prognostic predictive performance. The nomogram constructed based on the risk score and clinical information can accurately predicted the survival probability of patients with HCC. Patients with HCC in the high-risk groups have high immune scores and tend to generate an immunosuppressive microenvironment. They also exhibited a favorable response to immunotherapy, as evidenced by high tumor mutational burden, high immune checkpoint gene expression, high human leukocyte antigen gene expression, low tumor immune dysfunction and low exclusion scores. Additionally, the PANRS enabled the identification of 15 chemotherapeutic agents, including sorafenib, for patients with HCC with different risk levels, guiding clinical treatment. The signature gene LPCAT1 was upregulated in HCC cell lines. LPCAT1 knockdown markedly decreased HCC cell proliferation and migration.

Conclusion

PANRS can accurately predict the prognosis and immunotherapy response of patients with HCC and consequently guide individualized treatment.

Research progress on the P2X7 receptor in liver injury and hepatocellular carcinoma

Purinergic ligand-gated ion channel 7 receptor (P2X7 receptor) is an adenosine triphosphate (ATP)-gated ion channel that is widely distributed on the surfaces of immune cells and tissues such as those in the liver, kidney, lung, intestine, and nervous system. Hepatocellular carcinoma (HCC) is one of the most common malignancies with increasing incidence and mortality. Although many treatments for liver cancer have been studied, the prognosis for liver cancer is still very poor. Therefore, new liver cancer treatments are urgently needed. P2X7 receptor activation can secrete proinflammatory factors through the P2X7 receptor-NLRP3 signaling pathway, thereby affecting the progression of liver injury. The P2X7 receptor may be a target for growth inhibition of HCC cells and may affect the invasion and migration of HCC cells through the PI3K/AKT and AMPK signaling pathways. In recent years, P2X7 receptor antagonists or inhibitors have attracted widespread attention as therapeutic targets for hepatocellular carcinoma and liver injury. Therefore, this review covers the basic concepts of the P2X7 receptor and role of the P2X7 receptor in liver cancer and liver injury, providing new potential therapeutic targets for hepatocellular carcinoma and liver injury.

Ion channel Piezo1 activation promotes aerobic glycolysis in macrophages

Altered microenvironmental stiffness is a hallmark of inflammation. It is sensed by the mechanically activated cation channel Piezo1 in macrophages to induce subsequent immune responses. However, the mechanism by which the mechanosensitive signals shape the metabolic status of macrophages and tune immune responses remains unclear. We revealed that Piezo1-deficient macrophages exhibit reduced aerobic glycolysis in resting or liposaccharide (LPS)-stimulated macrophages with impaired LPS-induced secretion of inflammatory cytokines in vitro. Additionally, pretreatment with the Piezo1 agonist, Yoda1, or cyclical hydrostatic pressure (CHP) upregulated glycolytic activity and enhanced LPS-induced secretion of inflammatory cytokines. Piezo1-deficient mice were less susceptible to dextran sulfate sodium (DSS)-induced colitis, whereas Yoda1 treatment aggravated colitis. Mechanistically, we found that Piezo1 activation promotes aerobic glycolysis through the Ca²⁺-induced CaMKII-HIF1α axis. Therefore, our study revealed that Piezo1-mediated mechanosensitive signals Piezo1 can enhance aerobic glycolysis and promote the LPS-induced immune response in macrophages.

Withanolides from Withania somnifera Ameliorate Neutrophil Infiltration in Endotoxin-Induced Peritonitis by Regulating Oxidative Stress and Inflammatory Cytokines

Identification of novel anti-inflammatory strategies are needed to avoid the side effects associated with the currently available therapies. Use of anti-inflammatory herbal remedies is gaining attention. The purpose of the present investigation was to evaluate the pharmacological potential of the withanolide-rich root extracts of the medical plant Withania somnifera (L.) Dunal using in vivo and in vitro models of endotoxin-induced inflammation and oxidative stress. The pharmacological effects of W. somnifera root extracts were evaluated using a mouse model of endotoxin (lipopolysaccharide)-induced peritonitis and various relevant human cell lines. HPLC analysis of the W. somnifera root extracts identified the presence of various bioactive withanolides. In vivo challenge of mice with endotoxin resulted in the infiltration of various leukocytes, specifically neutrophils, along with monocytes and lymphocytes into the peritoneal cavity. Importantly, prophylactic treatment with W. somnifera inhibited the migration of neutrophils, lymphocytes, and monocytes and decreased the release of interleukin-1β, TNF-α, and interleukin-6 cytokines into the peritoneal cavity as identified by ELISA. Liver (glutathione peroxidase, glutathione, glutathione disulfide, superoxide dismutase, malondialdehyde, myeloperoxidase) and peritoneal fluid (nitrite) biochemical analysis revealed the antioxidant profile of W. somnifera. Similarly, in human HepG2 cells, W. somnifera significantly modulated the antioxidant levels. In THP-1 cells, W. somnifera decreased the secretion of interleukin-6 and TNF-α. In HEK-Blue reporter cells, W. somnifera inhibited TNF-α-induced nuclear factor-κB/activator protein 1 transcriptional activity. Our findings suggest the pharmacological effects of root extracts of W. somnifera rich in withanolides inhibit neutrophil infiltration, oxidative hepatic damage, and cytokine secretion via modulating the nuclear factor-κB/activator protein 1 pathway.

Inhibition of NEK7 Suppressed Hepatocellular Carcinoma Progression by Mediating Cancer Cell Pyroptosis

NIMA-related kinase 7 (NEK7) is a serine/threonine kinase involved in cell cycle progression via mitotic spindle formation and cytokinesis. It has been related to multiple cancers, including breast cancer, hepatocellular cancer, lung cancer, and colorectal cancer. Moreover, NEK7 regulated the NLRP3 inflammasome to activate Caspase-1, resulting in cell pyroptosis. In the present study, we investigated whether NEK7 is involved in cell pyroptosis of hepatocellular carcinoma (HCC). Interestingly, we found that NEK7 was significantly related to expression of pyroptosis marker GSDMD in HCC. We found that NEK7 expression was significantly correlated with GSDMD expression in bioinformatics analysis, and NEK7 expression was significantly co-expressed with GSDMD in our HCC specimens. Cell viability, migration, and invasion capacity of HCC cell lines were inhibited, and the tumor growth in the xenograft mouse model was also suppressed following knockdown of NEK7 expression. Mechanistic studies revealed that knockdown of NEK7 in HCC cells significantly upregulated the expression of pyroptosis markers such as NLRP3, Caspase-1, and GSDMD. Coculture of HCC cells stimulated hepatic stellate cell activation by increasing p-ERK1/2 and α-SMA. Knockdown of NEK7 impaired the stimulation of HCC cells. Therefore, downregulation of NEK7 inhibited cancer–stromal interaction by triggering cancer cell pyroptosis. Taken together, this study highlights the functional role of NEK7-regulated pyroptosis in tumor progression and cancer–stromal interaction of HCC, suggesting NEK7 as a potential target for a new therapeutic strategy of HCC treatment.

Injury Patterns after Falling down Stairs-High Ratio of Traumatic Brain Injury under Alcohol Influence

Falling down a staircase is a common mechanism of injury in patients with severe trauma, but the effect of varying fall height according to the number of steps on injury patterns in these patients has been little studied. In this retrospective study, prospectively collected data from a Level 1 Trauma Center in Germany were analyzed regarding the injury patterns of patients admitted through the trauma room with suspicion of multiple injuries following a fall down a flight of stairs between January 2016 and December 2019. In total 118 patients were examined which where consecutively included in this study. More than 80% of patients suffered a traumatic brain injury, which increased as a function of the number of stairs fallen. Therefore, the likelihood of intracranial hemorrhage increased with higher numbers of fallen stairs. Fall-associated bony injuries were predominantly to the face, skull and the spine. In addition, there was a high coincidence of staircase falls and alcohol intake. Due to a frequent coincidence of staircase falls and alcohol, the (pre-)clinical neurological assessment is complicated. As the height of the fall increases, severe traumatic brain injury should be anticipated and diagnostics to exclude intracranial hemorrhage and spinal injuries should be performed promptly to ensure the best possible patient outcome.

Pyroptosis-Mediated Periodontal Disease

Pyroptosis is a caspase-dependent process relevant to the understanding of beneficial host responses and medical conditions for which inflammation is central to the pathophysiology of the disease. Pyroptosis has been recently suggested as one of the pathways of exacerbated inflammation of periodontal tissues. Hence, this focused review aims to discuss pyroptosis as a pathological mechanism in the cause of periodontitis. The included articles presented similarities regarding methods, type of cells applied, and cell stimulation, as the outcomes also point to the same direction considering the cellular events. The collected data indicate that virulence factors present in the diseased periodontal tissues initiate the inflammasome route of tissue destruction with caspase activation, cleavage of gasdermin D, and secretion of interleukins IL-1β and IL-18. Consequently, removing periopathogens’ virulence factors that trigger pyroptosis is a potential strategy to combat periodontal disease and regain tissue homeostasis.

Moderate Beer Intake Downregulates Inflammasome Pathway Gene Expression in Human Macrophages

Simple Summary

Moderate consumption of fermented beverages is associated with prevention against diseases involving inflammation and immunity. Conversely, for high drinking levels, an increase of inflammatory mediators and the susceptibility to infections occur, which tend to offset the benefits in terms of health. Unfortunately, this area remains poorly understood. Inflammation is now recognized as an overwhelming burden for public health. Thus, subcellular molecular complexes such as the “inflammasomes” have been identified as key players in cellular stress and tissue damage, and as regulators of immune and inflammatory responses. Here, we investigated the impact of moderate intake of alcohol-free and traditional beer in humans on the inflammasome pathway of activated pro-inflammatory human macrophages. The results of this study showed that macrophages submitted to a pro-inflammatory stimulus to activate the inflammosome had a mitigated inflammatory response in the presence of blood serum obtained from healthy volunteers after consuming alcohol-free or traditional beer for four weeks (women one can and men two cans per day) compared to the response found in the presence of blood serum obtained before beer intake. This was shown by a decrease in end components of the inflammasome cascade (IL-1β and TNF) at gene expression and protein level as found with alcohol-free and traditional beer, respectively.

Abstract

Inflammasomes are key components of the innate immunity system that trigger the inflammatory response. Inappropriate activity of the inflammasome system has been linked to onset and perpetuation of inflammation in atherosclerotic plaques and cardiovascular disease. Low-to-moderate beer consumption is inversely associated with cardiovascular event presentation, while high levels of alcohol intake are associated with increased cardiovascular risk. Although fermented beverages have been suggested to exert their beneficial effects through their anti-oxidant and anti-inflammatory properties, little is known regarding the capacity of beer to modulate innate immunity cell responses. To this aim, primed or activated THP-1 macrophages were conditioned with human serum obtained from a prospective two-arms longitudinal crossover study to investigate the effect of a moderate and regular daily intake of beer, either alcohol-free or traditional, in the regulation of TLR-mediated inflammatory responses in healthy but overweight individuals. Conditioned macrophages with serum obtained after four-week intervention with alcohol-free beer significantly reduced the transcription of pro-inflammatory interleukins such as IL-1β and TNF. The serum of traditional beer consumers did not exhibit the same capacity as the serum of alcohol-free beer consumers to reduce gene expression of pro-inflammatory interleukins; however, serum from traditional beer consumers showed a regulatory effect at the protein level by significantly decreasing the intracellular protein levels of pro-IL-1β in primed macrophages and preventing cleaved-IL-1β protein release.

Acute Alcohol Intoxication Modulates Monocyte Subsets and Their Functions in a Time-Dependent Manner in Healthy Volunteers

Background

Excessive alcohol intake is associated with adverse immune response-related effects, however, acute and chronic abuse differently modulate monocyte activation. In this study, we have evaluated the phenotypic and functional changes of monocytes in acutely intoxicated healthy volunteers (HV).

Methods

Twenty-two HV consumed individually adjusted amounts of alcoholic beverages until reaching a blood alcohol level of 1‰ after 4h (T4). Peripheral blood was withdrawn before and 2h (T2), 4h (T4), 6h (T6), 24h (T24), and 48h (T48) after starting the experiment and stained for CD14, CD16 and TLR4. CD14^brightCD16^-, CD14^brightCD16⁺ and CD14^dimCD16⁺ monocyte subsets and their TLR4 expression were analyzed by flow cytometry. Inflammasome activation via caspase-1 in CD14⁺ monocytes was measured upon an ex vivo in vitro LPS stimulation. Systemic IL-1β and adhesion capacity of isolated CD14⁺ monocytes upon LPS stimulation were evaluated.

Results

The percentage of CD14⁺ monocyte did not change following alcohol intoxication, whereas CD14^brightCD16^- monocyte subset significantly increased at T2 and T24, CD14^brightCD16⁺ at T2, T4 and T6 and CD14^dimCD16⁺ at T4 and T6. The relative fraction of TLR4 expressing CD14⁺ monocytes as well as the density of TLR4 surface presentation increased at T2 and decreased at T48 significantly. TLR4⁺CD14⁺ monocytes were significantly enhanced in all subsets at T2. TLR4 expression significantly decreased in CD14^brightCD16^- at T48, in CD14^brightCD16⁺ at T24 and T48, increased in CD14^dimCD16⁺ at T2. IL-1β release upon LPS stimulation decreased at T48, correlating with TLR4 receptor expression. Alcohol downregulated inflammasome activation following ex vivo in vitro stimulation with LPS between T2 and T48 vs. T0. The adhesion capacity of CD14⁺ monocytes decreased from T2 with significance at T4, T6 and T48. Following LPS administration, a significant reduction of adhesion was observed at T4 and T6.

Conclusions

Alcohol intoxication immediately redistributes monocyte subsets toward the pro-inflammatory phenotype with their subsequent differentiation into the anti-inflammatory phenotype. This is paralleled by a significant functional depression, suggesting an alcohol-induced time-dependent hyporesponsiveness of monocytes to pathogenic triggers.