225 research outputs found
Cactus pear fruit extract exerts anti-inflammatory effects in carrageenin-induced rat pleurisy
Nutritional research has recently shifted from alleviating nutrient deficiencies to chronic disease prevention. In this study activity of cactus pear fruit extract (CPFE) from Opuntia ficus-indica (L.) Mill. has been investigated in carrageenin-induced pleurisy, a rat model of acute inflammation. In our experimental design rat pleurisy was achieved by the injection of 0.2 ml of λ-carrageenin in the pleural cavity. At selected time points, rats were sacrificed; cells recruited in pleura were counted and exudates collected to analyse inflammatory parameters such as NO, PGE2, IL-1β, TNF-α. CPFE (in the range between 5 and 20 g fresh fruit equivalent/kg), orally given 30 min before the injection, time- and dose-dependently reduced the exudate volume (up to 72%) and the number of leukocytes recruited in the pleural cavity (up to 96%), at 24 h. These anti-inflammatory effects were accompanied by an inhibited release of inflammatory mediators (PGE2, NO, IL-1β, TNF-α). Our in vivo findings unveil for the first time an anti-inflammatory potential for cactus pear fruit and suggest further investigations to propose cactus pear fruit as a functional food able to improve health, possibly by preventing inflammation-based disorders. © 2015, International Society for Horticultural Science. All rights reserved
The IkB kinase inhibitor nuclear factor-kB essential modulator–binding domain peptide for inhibition of balloon injury-induced neointimal formation
Objective—The activation of nuclear factor-kB (NF-kB) is a crucial step in the arterial wall’s response to injury. The
identification and characterization of the NF-kB essential modulator– binding domain (NBD) peptide, which can block
the activation of the IkB kinase complex, have provided an opportunity to selectively abrogate the inflammation-induced
activation of NF-kB. The aim of the present study was to evaluate the effect of the NBD peptide on neointimal
formation.<br></br>
Methods and Results—In the rat carotid artery balloon angioplasty model, local treatment with the NBD peptide (300
microg/site) significantly reduced the number of proliferating cells at day 7 (by 40%; P<0.01) and reduced injury-induced neointimal formation (by 50%; P<0.001) at day 14. These effects were associated with a significant reduction of NF-kB activation and monocyte chemotactic protein-1 expression in the carotid arteries of rats treated with the peptide. In addition, the NBD peptide (0.01 to 1 micromol/L) reduced rat smooth muscle cell proliferation, migration, and invasion in
vitro. Similar results were observed in apolipoprotein E-/-, mice in which the NBD peptide (150 microg/site) reduced wire-induced neointimal formation at day 28 (by 47%; P<0.01).<br></br>
Conclusion—The NBD peptide reduces neointimal formation and smooth muscle cell proliferation/migration, both effects
associated with the inhibition of NF-kB activation
Cactus Pear Fruit Extract exerts anti-inflammatory effects on carrageenan-induced rat pleurisy.
Apolipoprotein A-I (ApoA-I) Mimetic Peptide P2a by Restoring CholesterolEsterification Unmasks ApoA-I Anti-Inflammatory Endogenous Activity In Vivo. CO-FIRST AUTHOR
The acute-phase protein haptoglobin (Hpt) binds apolipoprotein A-I (ApoA-I) and impairs its action on lecithin-cholesterol acyltransferase, an enzyme that plays a key role in reverse cholesterol transport. We have previously shown that an ApoA-I mimetic peptide, P2a, displaces Hpt from ApoA-I, restoring the enzyme activity in vitro. The aim of this study was to evaluate whether P2a displaces Hpt from ApoA-I in vivo and whether this event leads to anti-inflammatory activity. Mice received subplantar injections of carrageenan. Paw volume was measured before the injection and 2, 4, 6, 24, 48, 72, and 96 h thereafter. At the same time points, concentrations of HDL cholesterol (C) and cholesterol esters (CEs) were measured by high-performance liquid chromatography, and Hpt and ApoA-I plasma levels were evaluated by enzyme-linked immunosorbent assay. Western blotting analysis for nitric-oxide synthase and cyclooxygenase (COX) isoforms was also performed on paw homogenates. CEs significantly decreased in carrageenan-treated mice during edema development and negatively correlated with the Hpt/ApoA-I ratio. P2a administration significantly restored the CE/C ratio. In addition, P2a displayed an anti-inflammatory effect on the late phase of edema with a significant reduction in COX2 expression coupled to an inhibition of prostaglandin E2 synthesis, implying that, in the presence of P2a, CE/C ratio rescue and edema inhibition were strictly related. In conclusion, the P2a effect is due to its binding to Hpt with consequent displacement of ApoA-I that exerts anti-inflammatory activity. Therefore, it is feasible to design drugs that, by enhancing the physiological endogenous protective role of ApoA-I, may be useful in inflammation-based diseases
Olive leaf extract inhibits metastatic melanoma spread through suppression of epithelial to mesenchymal transition
Olive tree leaves are an abundant source of bioactive compounds with several beneficial effects for human health, including a protective role against many types of cancer. In this study, we investigated the effect of an extract, obtained from olive tree (Olea europaea L.) leaves (OLE), on proliferation, invasion, and epithelial to mesenchymal transition (EMT) on metastatic melanoma, the highly aggressive form of skin cancer and the deadliest diseases. Our results demonstrated that OLE inhibited melanoma cells proliferation through cell cycle arrest and induction of apoptotic cell death. Moreover, OLE suppressed the migration, invasion, and colonies formation of human melanoma cells. Similar to our in vitro findings, we demonstrated that the oral administration of OLE inhibited cutaneous tumor growth and lung metastasis formation in vivo by modulating the expression of EMT related factors. In addition, the anti-proliferative and anti-invasive effects of OLE against melanoma were also related to a simultaneous targeting of mitogen-activated protein kinase and PI3K pathways, both in vitro and in vivo. In conclusion, our findings suggest that OLE has the potential to inhibit the metastatic spread of melanoma cells thanks to its multifaceted mechanistic effects, and may represent a new add-on therapy for the management of metastatic melanoma
Paper-based electrochemical device for the determination of H2S in murine lysates for liquid biopsy application
Background: Hydrogen Sulfide (H2S) is a biologically active endogenous gas, produced in mammalian tissues, which plays a critical role in several pathophysiological processes, including oncogenesis. This gas-transmitter can exert diametrically opposite effects on neoplastic cell proliferation, depending on the duration and concentration of H2S exposure. Due to this dual role, antineoplastic drugs, aimed at modulating H2S levels, are attracting considerable interest in both research and clinical settings. On this basis, H2S could serve as a diagnostic biomarker, potentially indicating the presence and stage of a tumor in body fluids that can be analyzed by liquid biopsy. Results: In this work, an electrochemical sensor, screen-printed on filter paper, and then modified with a dispersion of Prussian blue, synthesized directly on the paper, was developed in order to detect H2S in tissue lysates. After the optimization of several experimental parameters, the sensor was analytically characterized in standard solution, achieving a good repeatability and a detection limit of 3 μM, and the repeatability of the entire platform appeared to be lower than 10 %. The sensor was then applied to determine H2S in biological samples, including a murine skin lysate, two pharmacologically treated neoplastic murine lysates, and an untreated neoplastic murine lysate, obtaining results in agreement with those observed with the standard methylene blue-based assay for H2S determination, demonstrating the applicability of the developed electroanalytical method for liquid biopsy. Significance and novelty: It might represent a significant revolution in cancer diagnosis, and the use of point of care (PoC) platforms is a promising strategy to speed up and simplify operations, providing rapid and on-site analysis. In particular, the possibility of using portable miniaturized sensors allowed to reduce the amount of sample to analyzed: it usually represents an issue of traditional approaches
Crucial role of androgen receptor in vascular H2S biosynthesis induced by testosterone.
BACKGROUND AND PURPOSE:
Hydrogen sulphide (H2S) is a gaseous mediator strongly involved in cardiovascular homeostasis, where it provokes vasodilation. Having previously shown that H2S contributes to testosterone (T) induced vasorelaxation, here we aim to uncover the mechanisms underlying this effect.
EXPERIMENTAL APPROACH:
H2S biosynthesis was evaluated in rat isolated aorta rings following androgen receptor (AR) stimulation. Co-immunoprecipitation and surface plasmon resonance analysis have been performed to investigate mechanisms involved in AR activation.
KEY RESULTS:
H2S biosynthesis is associated to activation of AR by testosterone or androgen agonist mesterolone and blocked by AR antagonist nilutamide. This event is linked to AR-multicomplex-derived heath shock protein 90 (hsp90), since its specific inhibitor geldanamycin strongly reduced T-induced H2S production. Neither progesterone nor 17-β-oestradiol actions did account for H2S release. Furthermore, we found that cystathionine gamma lyase (CSE), the main vascular H2S-synthesizing enzyme, is physically associated to AR/hsp90 complex and the generation of such a ternary system represents a key event leading to CSE activation. Finally, H2S levels in human blood collected from male healthy volunteers were higher than those observed in female samples.
CONCLUSIONS AND IMPLICATIONS:
Here, we demonstrated that selective activation of the AR is essential for H2S biosynthesis within vascular tissue and this event is based on formation of a ternary complex among CSE, AR and hsp90. This novel molecular mechanism operating in vascular district, corroborated by higher H2S level in males, suggested that L-cysteine/CSE/H2S pathway may be preferentially activated in males leading to a gender-related H2S biosynthesis
PPARɣ drives IL-33-dependent ILC2 pro-tumoral functions
Group 2 innate lymphoid cells (ILC2s) play a critical role in protection against helminths and in diverse inflammatory diseases by responding to soluble factors such as the alarmin IL-33, that is often overexpressed in cancer. Nonetheless, regulatory factors that dictate ILC2 functions remain poorly studied. Here, we show that peroxisome proliferator-activated receptor gamma (PPARγ) is selectively expressed in ILC2s in humans and in mice, acting as a central functional regulator. Pharmacologic inhibition or genetic deletion of PPARγ in ILC2s significantly impair IL-33-induced Type-2 cytokine production and mitochondrial fitness. Further, PPARγ blockade in ILC2s disrupts their pro-tumoral effect induced by IL-33-secreting cancer cells. Lastly, genetic ablation of PPARγ in ILC2s significantly suppresses tumor growth in vivo. Our findings highlight a crucial role for PPARγ in supporting the IL-33 dependent pro-tumorigenic role of ILC2s and suggest that PPARγ can be considered as a druggable pathway in ILC2s to inhibit their effector functions. Hence, PPARγ targeting might be exploited in cancer immunotherapy and in other ILC2-driven mediated disorders, such as asthma and allergy
FS536, a novel nitric oxide-releasing doxorubicin hybrid, reverts multidrug resistance in lung cancer cells
The design of molecular hybrids that chemically conjugate nitric oxide (NO)-donors with anticancer drugs, offering site-specific and time-controlled properties, is a promising strategy in cancer therapy. In this work, we designed, synthesized, and characterized a novel doxorubicin (DOXO)-NO-donor hybrid, named FS536, by chemically conjugating DOXO with a diazeniumdiolate moiety. Upon incubation in human serum, FS536 simultaneously released both DOXO and NO through enzymatic hydrolysis. FS536 significantly inhibited the proliferation of the DOXO-resistant A549 lung cancer cell line (A549-DR), overcoming the resistance typically observed with DOXO alone. This enhanced efficacy is attributed to the release of NO, which induces the nitration of the MRP1 efflux pump, reducing its activity, increasing intracellular drug concentrations, and thus sensitizing resistant cells to DOXO. Our findings suggest that FS536 is a promising therapeutic strategy for combating multidrug-resistant cancers by leveraging the synergistic effects of DOXO and NO
Circulating innate lymphoid cells are dysregulated in patients with prostate cancer
Background: Prostate cancer (PCa) is the second most common cancer affecting men globally, especially those aged 50 years and above. Despite substantial progress in terms of both prognosis and therapy, PCa remains a significant health concern, necessitating the identification of novel therapeutic targets. Innate lymphoid cells (ILCs) have emerged as critical modulators of tumor immunity, exhibiting both pro- and antitumoral effects. However, little is known yet about their contribution in PCa. This study investigated the phenotypic and functional profiles of ILC subsets in the peripheral blood mononuclear cells (PBMCs) of patients with PCa stratified by Gleason score. Methods: PBMCs were isolated by Lymphoprep. ILC frequency and activity were evaluated by flow cytometry. The levels of ILC-activating cytokines were analyzed by multiplex assay in the serum of healthy donors (HDs) and patients with PCa. To evaluate the crosstalk between ILC2s and cancer cells, PC3 and DU145 human PCa cell lines were used. Results: We found a stage-dependent increase in the protumoral ILC2 frequency and a concurrent decrease in antitumoral ILC1s in patients with PCa compared with healthy controls. Interestingly, the frequency of ILC2s was higher in patients with elevated prostate-specific antigen (PSA) values, suggesting their potential as molecular predictor for defining the risk category of patients with PCa at diagnosis. Importantly, patients with PCa exhibited hyperactivated ILC2s, characterized by elevated interleukin (IL)-13 and IL-5 production, while ILC1s displayed reduced tumor necrosis factor (TNF)-α and interferon (IFN)-γ secretion. Furthermore, serum levels of ILC2-activating cytokines IL-33, IL-18, and prostaglandin D2 (PGD2) were elevated in patients with PCa. In vitro co-culture experiments demonstrated that PCa cell lines, capable of secreting these cytokines, could directly enhance ILC2 activity. Likewise, ILC2-derived IL-13 promoted PCa cell migration and invasion. Conclusions: Collectively, our findings highlight a dysregulated ILC profile in PCa, characterized by ILC2 dominance and heightened activity at the expense of ILC1s, suggesting both ILC1s and ILC2s as potential therapeutic targets for PCa treatment
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