1,720,999 research outputs found
Inside platelet-leukocyte cross-talk
No full textIn this issue of Blood, Laidlaw and colleagues show that in subjects with aspirin exacerbated respiratory disease (AERD), dysregulated platelet-leukocyte crosstalk may be partly responsible for the respiratory tissue inflammation and overproduction of cysteinyl leukotrienes, providing new clues for the treatment of the disease
Platelets, cyclooxygenases, and colon cancer.
No full textA growing body of evidence supports the central role of platelets in early events of tumorigenesis and metastasis. Activated platelets, in response to tissue damage, induce a proinflammatory program involving the aberrant expression of cyclooxygenase (COX)-2, which leads to increased tissue concentrations of the proinflammatory and protumorigenic prostaglandin E2. The central role of platelet activation in cancer development is sustained by the analysis of clinical studies with aspirin showing an anti-cancer efficacy by the drug, even at the low doses used for the prevention of atherothrombosis. Low-dose aspirin acts as an antiplatelet agent by causing an irreversible inactivation of platelet COX-1 activity and the synthesis of thromboxane A2. Further experimental and clinical studies are ongoing to confirm the central role of platelets in the development of inflammation and cancer. The corroboration of this hypothesis will open new opportunities for the prevention and treatment of cancer. In addition to the possible use of traditional antithrombotic agents, the recent identification of novel molecular determinants involved in the cross-talk between platelets and other cellular player of tumorigenesis and metastasis has led to the suggestion of novel therapeutic strategies in oncology
Mode of Action of Aspirin as a Chemopreventive Agent
No full textAspirin taken for several years at doses of at least 75 mg daily reduced long-term incidence and mortality due to colorectal cancer. The finding of aspirin benefit at low-doses given once daily, used for cardioprevention, locates the antiplatelet effect of aspirin at the center of its antitumor efficacy. In fact, at low-doses, aspirin acts mainly by an irreversible inactivation of platelet cyclooxygenase (COX)-1 in the presystemic circulation, which translates into a long-lasting inhibition of platelet function. Given the short half-life of aspirin in the human circulation(approximately 20 min) and the capacity of nucleated cells to resynthesize the acetylated COX-isozyme(s), it seems unlikely that a nucleated cell could be the target of aspirin chemoprevention. These findings convincingly suggest that colorectal cancer and atherothrombosis may share a common mechanism of disease, i.e. platelet activation in response to epithelial(in tumorigenesis) and endothelial(in tumorigenesis and atherothrombosis) injury. Activated platelets may also enhance the metastatic potential of cancer cells (through a direct interaction and/or the release of soluble mediators or exosomes) at least in part by inducing the overexpression of COX-2. COX-independent mechanisms of aspirin, such as the inhibition of NF-kB signaling and Wnt/β-catenin signaling and the acetylation of extra-COX proteins, have been suggested to play a role in its chemopreventive effects. However, their relevance remains to be demonstrated in vivo at clinical doses
Role of Platelets in Inflammation and Cancer: Novel Therapeutic Strategies
No full textPlatelets play a central role in inflammation through their direct interaction with other cell types, such as leucocytes and endothelial cells, and by the release of many factors, that is, lipids [such as thromboxane (TX)A2 ] and proteins (a wide number of angiogenic and growth factors) stored in α-granules, and adenosine diphosphate (ADP), stored in dense granules. These platelet actions trigger autocrine and paracrine activation processes that lead to leucocyte recruitment into different tissues and phenotypic changes in stromal cells which contribute to the development of different disease states, such as atherosclerosis and atherothrombosis, intestinal inflammation and cancer. The signals induced by platelets may cause pro-inflammatory and malignant phenotypes in other cells through the persistent induction of aberrant expression of cyclooxygenase (COX)-2 and increased generation of prostanoids, mainly prostaglandin (PG)E2 . In addition to cardiovascular disease, enhanced platelet activation has been detected in inflammatory disease and intestinal tumourigenesis. Moreover, the results of clinical studies have shown that the antiplatelet drug aspirin reduces the incidence of vascular events and colorectal cancer. All these pieces of evidence support the notion that colorectal cancer and atherothrombosis may share a common mechanism of disease, that is, platelet activation in response to epithelial (in tumourigenesis) and endothelial (in tumourigenesis and atherothrombosis) injury. Extensive translational medicine research is necessary to obtain a definitive mechanistic demonstration of the platelet-mediated hypothesis of colon tumourigenesis. The results of these studies will be fundamental to support the clinical decision to recommend the use of low-dose aspirin, and possibly other antiplatelet agents, in primary prevention, that is, even for individuals at low cardiovascular risk
Biology and pharmacology of platelet-type 12-lipoxygenase in platelets, cancer cells, and their crosstalk
Full text linkPlatelet-type lipoxygenase (pl12-LOX), encoded by ALOX12, catalyzes the production of the lipid mediator 12Shydroperoxyeicosa-5,8,10,14-tetraenoic acid (12S-HpETE), which is quickly reduced by cellular peroxidases to form 12(S)-hydroxy-5,8,10,14-eicosatetraenoic acid (12S-HETE). Platelets express high levels of pl12-LOX and generate considerable amounts of 12S-HETE from arachidonic acid (AA; C20:4, n-6). The development of sensitive chiral liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods has allowed the accurate quantification of 12S-HETE in biological samples. Moreover, advances in the knowledge of the mechanism of action of 12S-HETE have been achieved. The orphan G-protein-coupled receptor 31 (GPR31) has been identified as the high-affinity 12S-HETE receptor. Moreover, upon platelet activation, 12S-HETE is produced, and significant amounts are found esterified to membrane phospholipids (PLs), such as phosphatidylethanolamine (PE) and phosphatidylcholine (PC), promoting thrombin generation. Platelets play many roles in cancer metastasis. Among them, the platelets' ability to interact with cancer cells and transfer platelet molecules by the release of extracellular vesicles (EVs) is noteworthy. Recently, it was found that platelets induce epithelial-mesenchymal transition(EMT) in cancer cells, a phenomenon known to confer high-grade malignancy, through the transfer of pl12-LOX contained in platelet-derived EVs. These cancer cells now generate 12-HETE, considered a key modulator of cancer metastasis. Interestingly, 12-HETE was mainly found esterified in plasmalogen phospholipids of cancer cells. This review summarizes the current knowledge on the regulation and functions of pl12-LOX in platelets and cancer cells and their crosstalk. Novel approaches to preventing cancer and metastasis by the pharmacological inhibition of pl12-LOX and the internalization of mEVs are discussed
A real-world analysis of adherence, biochemical outcomes, and healthcare costs in patients treated with rosuvastatin/ezetimibe as single-pill combination vs. free combination in Italy
No full textAims: To compare medication adherence, lipid goal attainment, and healthcare costs between patients receiving a single-pill combination (SPC) vs. a free combination treatment (FCT) of rosuvastatin/ezetimibe (ROS/EZE) in Italy. Methods and results: Administrative databases of healthcare entities covering ∼7 million individuals were used to identify adults prescribed with ROS/EZE as SPC or FCT between January 2018 and June 2020. Adherence was calculated as the proportion of days covered (PDC) after cohort balancing by propensity score matching. Patients with available LDL cholesterol testing were assessed for the proportion of those who at baseline were above lipid targets recommended by ESC/EAS Guidelines for their cardiovascular risk category and reached the target during follow-up. Among 25 886 patients on SPC and 7309 on FCT, adherent patients were more represented in SPC than FCT cohort (56.8 vs. 44.5%, P < 0.001), and this difference remained significant (P < 0.001) after stratification by cardiovascular risk (very high, high, and other). The proportion of patients reaching LDL cholesterol target at 1 year follow-up was significantly (P < 0.001) higher in SPC vs. FCT cohort: 35.4 vs. 23.8% for very high cardiovascular risk, 46.9 vs. 23.1% for high risk and 71.6 vs. 49.5% for other risk. Total healthcare costs per patient at 1 year follow-up were lower in SPC vs. FCT users (2337€ vs. 1890€, P < 0.001). In both cohorts, costs were mainly driven by drug expenses and hospitalizations. Conclusion: This real-world analysis in dyslipidaemic patients found that treatment with ROS/EZE as SPC resulted in better adherence, higher chances of reaching lipid goals, and cost savings over FCT, in all cardiovascular risk categories
Carbenoxolone inhibits volume-regulated anion conductance in cultured rat cortical astroglia.
No full textAn aquaporin-4/transient receptor potential vanilloid 4 (AQP4/TRPV4) complex is essential for cell-volume control in astrocytes.
No full textDifferential Adherence to Free and Single-Pill Combination of Rosuvastatin/Ezetimibe: Findings from a Real-World Analysis in Italy
Full text linkIntroduction: Adherence to cardiovascular drug treatment can significantly benefit from a reduced pill burden, but data on this matter derived from real-life settings are currently scanty. This analysis assessed the possible changes in adherence in patients treated with rosuvastatin and ezetimibe (ROS/EZE) as free multi-pill combination who switched to ROS/EZE as single-pill combination in the setting of real clinical practice in Italy. Methods: A retrospective analysis was conducted on the administrative databases for a catchment area of about seven million health-assisted residents. Adults receiving ROS/EZE as a single-pill combination from January 2010 to June 2020 (followed up to 2021) were identified. The date of the first prescription of single-pill combination of ROS/EZE was considered as the index date. The analysis included the users of ROS/EZE as a free combination during the year before the index date. Baseline demographic and clinical characteristics were collected during the period of data availability prior to the index date. Adherence to therapy was evaluated as proportion of days covered (PDC), namely the percentage of days during which a patient had access to medication, in the 12-month interval preceding or following the index date (PDC 75% adherence). Results: A total of 1219 patients (61.1% male, aged 66.2 +/- 10.4 years) were included. Cardiovascular comorbidities were found in 83.3% of them, diabetes in 26.4%, and a combination of both in 16.2%. Single-pill combination of ROS/EZE was associated with a higher proportion of adherent patients compared to free-pill combination (75.2% vs 51.8%, p < 0.001). Conclusions: This real-world analysis suggested that switching from a regimen based on separate pills to one based on a single-pill combination resulted in improved adherence to ROS/EZE therapy
A retrospective Italian analysis on the characteristics of invasive fungal infections in the intensive care unit setting: CHARTER‐IFI study
Full text linkBackground: Invasive fungal infections (IFI), prevalent in critically ill ICU patients, have gained attention due to post-COVID-19 epidemiological shifts. Notably, COVID-19-associated aspergillosis and candidiasis pose significant risks. WHO recognises key fungal pathogens, emphasising the need for enhanced research and interventions. Methods: The CHARTER-IFI study retrospectively examines 186,310 individuals admitted to ICUs in Italy from 01/01/2012-01/09/2023, utilising administrative databases covering around 10 million inhabitants. Adult patients were included having at least one ICU discharge diagnosis of IFI at their first IFI-related hospitalisation and having at least 12 months of available data prior to this hospitalisation. Results: A total of 746 IFI patients discharged from ICU (incidence of 4.0 per 1000 ICU-hospitalised patients), were included. Median age was 68 years, 63% were males, and the overall Charlson Comorbidity Index was 2.2. The top three diagnoses were candidiasis (N = 501, 2.7/1000 ICU-hospitalised patients), aspergillosis (N = 71, 0.4/1000), and pneumocystosis (N = 55, 0.3/1000). The evaluation of the comorbidity profile in IFI patients revealed the presence of hypertension (60.5%), use of systemic GC/antibacterials (45.3% during 12 months before and 18.6% during 3 months before hospital admission), cancer (23.1%), diabetes (24.3%) and cardiovascular diseases (23.9%). The mean (+/- SD) length of hospitalisation in ICU was 19.9 +/- 24.1 days (median 11 days), and deaths occurred in 36.1% of IFI patients (within 30 days from discharge). Conclusions: This retrospective analysis among ICU-hospitalised patients described the burden of IFI in ICU, and its understanding could be crucial to strengthen surveillance, investments in research, and public health interventions as required by WHO
- …
