52 research outputs found
Differential effects of malignant mesothelioma cells on THP-1 monocytes and macrophages
No full textMalignant mesothelioma (MM) is a highly fatal tumor arising from inner body membranes, whose extensive growth is facilitated by its week immunogenicity and by its ability to blunt the immune response which should arise from the huge mass of leukocytes typically infiltrating this tumor. It has been reported that the inflammatory infiltrate found in MM tissues is characterized by a high prevalence of macrophages. Thus, in this work we evaluated the ability of human MM cells to modulate the inflammatory phenotype of human THP-1 monocytes and macrophages, a widely used in vitro model of monocyte/macrophage differentiation. Furthermore, we tested the hypothesis that the exposure to MM cells could alter the differentiation of THP-1 monocytes favoring the development of alternatively activated, tumor-supporting macrophages. Our data prove for the first time that MM cells can polarize monocytes towards an altered inflammatory phenotype and macrophages towards an immunosuppressive phenotype. Moreover, we demonstrate that monocytes cocultivated with MM cells 'keep a memory' of their encounter with the tumor which influences their differentiation to macrophages. On the whole, we provide evidence that MM cells exert distinct, cell-specific effects on monocytes and macrophages. The thorough characterization of such effects may be of a crucial importance for the rational design of new immunotherapeutic protocols
Trans-crocetin improves amyloid-β degradation in monocytes from Alzheimer's Disease patients
No full textHerbal medicines have been recently employed in research and clinical studies for the potential treatment of behavioral and psychological symptoms associated with Alzheimer's Disease (AD) and other types of dementia. The present study investigates the effect of trans-crocetin, an active constituent of Crocus sativus L., to restore in vitro the reduced ability of AD patients' monocytes to degrade amyloid-β(1-42) (Aβ42). CD14(+) monocytes from 22 sporadic AD patients with moderate cognitive impairment were isolated; then, the role of trans-crocetin, purified from saffron extracts, was evaluated in terms of Aβ42 degradation rate through flow cytometry, as well as expression of cathepsin B by Western blotting. We observed that low micromolar doses of trans-crocetin enhanced Aβ42 degradation in AD monocytes through the upregulation of the lysosomal protease cathepsin B. CA074Me, a potent and selective cathepsin B inhibitor, counteracted such trans-crocetin-induced effect. These data suggest that the carotenoid trans-crocetin improves in vitro the clearance of Aβ42 through the involvement of cathepsin B, and this could be of value in developing a new anti-amyloid strategy in AD
Distinct Modulation of Human Myeloid and Plasmacytoid Dendritic Cells by Anandamide in Multiple Sclerosis
No full textObjective The immunopathogenesis of multiple sclerosis (MS) has always been thought to be driven by chronically activated and autoreactive Th-1 and Th-17 cells. Recently, dendritic cells (DCs) have also been thought to significantly contribute to antigenic spread and to maturation of adaptive immunity, and have been linked with disease progression and exacerbation. However, the role of DCs in MS pathogenesis remains poorly understood. Methods We compared the level of cytokine production by myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) in healthy subjects and MS patients, following in vitro stimulation of Toll-like receptors 7/8. We also evaluated the effect of the main endocannabinoid, anandamide (AEA), in these DC subsets and correlated cytokine levels with defects in the endocannabinoid system. Results mDCs obtained from MS patients produce higher levels of interleukin-12 and interleukin-6, whereas pDCs account for lower levels of interferon- compared to healthy subjects. AEA significantly inhibited cytokine production from healthy mDCs and pDCs, as well as their ability to induce Th-1 and Th-17 lineages. Moreover, we found that in MS only pDCs lack responsiveness to cytokine inhibition induced by AEA. Consistently, this specific cell subset expresses higher levels of the anandamide hydrolase fatty acid amide hydrolase (FAAH). Interpretation Our data disclose a distinct immunomodulatory effect of AEA in mDCs and pDCs from MS patients, which may reflect an alteration of the expression of FAAH, thus forming the basis for the rational design of new endocannabinoid-based immunotherapeutic agents targeting a specific cell subset
Trans-crocetin improves amyloid-beta degradation in monocytes from Alzheimer's Disease patients
No full textHerbal medicines have been recently employed in research and clinical studies for the potential treatment of behavioral and psychological symptoms associated with Alzheimer's Disease (AD) and other types of dementia. The present study investigates the effect of trans-crocetin, an active constituent of Crocus sativus L., to restore in vitro the reduced ability of AD patients' monocytes to degrade amyloid-beta((1-42)) (A beta(42)). CD14(+) monocytes from 22 sporadic AD patients with moderate cognitive impairment were isolated; then, the role of trans-crocetin, purified from saffron extracts, was evaluated in terms of A beta(42) degradation rate through flow cytometry, as well as expression of cathepsin B by Western blotting. We observed that low micromolar doses of trans-crocetin enhanced A beta(42) degradation in AD monocytes through the upregulation of the lysosomal protease cathepsin B. CA074Me, a potent and selective cathepsin B inhibitor, counteracted such trans-crocetin-induced effect. These data suggest that the carotenoid trans-crocetin improves in vitro the clearance of A beta(42) through the involvement of cathepsin B, and this could be of value in developing a new anti-amyloid strategy in AD. (C) 2016 Elsevier B.V. All rights reserved
Epidemiological characterization of SARS-CoV-2 variants in children over the four COVID-19 waves and correlation with clinical presentation (vol 12, 10194, 2022)
No full textSevere covid-19 complicated by cerebral venous thrombosis in a newborn successfully treated with remdesivir, glucocorticoids, and hyperimmune plasma
No full textSevere acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for the coronavirus disease 2019 (COVID-19) pandemic, affecting all age groups with a wide spectrum of clinical presentation ranging from asymptomatic to severe interstitial pneumonia, hyperinflammation, and death. Children and infants generally show a mild course of the disease, although infants have been observed to have a higher risk of hospitalization and severe outcomes. Here, we report the case of a preterm infant with a severe form of SARS-CoV-2 infection complicated by cerebral venous thrombosis successfully treated with steroids, hyperimmune plasma, and remdesivir
Anandamide Suppresses Proinflammatory T Cell Responses In Vitro through Type-1 Cannabinoid Receptor-Mediated mTOR Inhibition in Human Keratinocytes.
No full textThe endocannabinoid system comprises cannabinoid receptors 1 and 2 (CB1 and CB2), their endogenous ligands, anandamide (AEA) and 2-arachidonoylglycerol, and metabolic enzymes of these ligands. The endocannabinoid system has recently been implicated in the regulation of various pathophysiological processes of the skin that include immune competence and/or tolerance of keratinocytes, the disruption of which might promote the development of skin diseases. Recent evidence showed that CB1 in keratinocytes limits the secretion of proinflammatory chemokines, suggesting that this receptor might also regulate T cell dependent inflammatory diseases of the skin. In this article, we sought to investigate the cytokine profile of IFN-γ-activated keratinocytes, and found that CB1 activation by AEA suppressed production and release of signature TH1- and TH17-polarizing cytokines, IL-12 and IL-23, respectively. We also set up cocultures between a conditioned medium of treated keratinocytes and naive T cells to disclose the molecular details that regulate the activation of highly proinflammatory TH1 and TH17 cells. AEA-treated keratinocytes showed reduced an induction of IFN-γ-producing TH1 and IL-17-producing TH17 cells, and these effects were reverted by pharmacological inhibition of CB1 Further analyses identified mammalian target of rapamycin as a proinflammatory signaling pathway regulated by CB1, able to promote either IL-12 and IL-23 release from keratinocytes or TH1 and TH17 polarization. Taken together, these findings demonstrate that AEA suppresses highly pathogenic T cell subsets through CB1-mediated mammalian target of rapamycin inhibition in human keratinocytes. Thus, it can be speculated that the latter pathway might be beneficial to the physiological function of the skin, and can be targeted toward inflammation-related skin diseases
TRPV1 channels are critical brain inflammation detectors and neuropathic pain biomarkers in mice
No full textThe capsaicin receptor TRPV1 has been widely characterized in the sensory system as a key component of pain and inflammation. A large amount of evidence shows that TRPV1 is also functional in the brain although its role is still debated. Here we report that TRPV1 is highly expressed in microglial cells rather than neurons of the anterior cingulate cortex and other brain areas. We found that stimulation of microglial TRPV1 controls cortical microglia activation per se and indirectly enhances glutamatergic transmission in neurons by promoting extracellular microglial microvesicles shedding. Conversely, in the cortex of mice suffering from neuropathic pain, TRPV1 is also present in neurons affecting their intrinsic electrical properties and synaptic strength. Altogether, these findings identify brain TRPV1 as potential detector of harmful stimuli and a key player of microglia to neuron communication
Effects of palmitoylation of Cys(415) in helix 8 of the CB1 cannabinoid receptor on membrane localization and signalling
No full textBACKGROUND AND PURPOSE
The CB1 cannabinoid receptor is regulated by its association with membrane microdomains such as lipid rafts. Here, we investigated the role of palmitoylation of the CB1 receptor by analysing the functional consequences of site-specific mutation of Cys415, the likely site of palmitoylation at the end of helix 8, in terms of membrane association, raft targeting and signalling.
EXPERIMENTAL APPROACH
The palmitoylation state of CB1 receptors in rat forebrain was assessed by depalmitoylation/repalmitoylation experiments. Cys(415) was replaced with alanine by site-directed mutagenesis. Green fluorescence protein chimeras of both wild-type and mutant receptors were transiently expressed and functionally characterized in SH-SY5Y cells and HEK-293 cells by means of confocal microscopy, cytofluorimetry and competitive binding assays. Confocal fluorescence recovery after photobleaching was used to assess receptor membrane dynamics, whereas signalling activity was assessed by [S-35]GTP gamma S, cAMP and co-immunoprecipitation assays.
KEY RESULTS
Endogenous CB1 receptors in rat brain were palmitoylated. Mutation of Cys(415) prevented the palmitoylation of the receptor in transfected cells and reduced its recruitment to plasma membrane and lipid rafts; it also increased protein diffusional mobility. The same mutation markedly reduced the functional coupling of CB1 receptors with G-proteins and adenylyl cyclase, whereas depalmitoylation abolished receptor association with a specific subset of G-proteins.
CONCLUSIONS AND IMPLICATIONS
CB1 receptors were post-translationally modified by palmitoylation. Mutation of Cys(415) provides a receptor that is functionally impaired in terms of membrane targeting and signalling
Effects of verapamil added-on trandolapril therapy in hypertensive type 2 diabetes patients with microalbuminuria: the BENEDICT-B randomized trial
No full textOBJECTIVES:
To address whether nondihydropyridine calcium-channel blocker added-on angiotensin-converting-enzyme inhibitor therapy ameliorates albuminuria and cardiovascular outcomes in type 2 diabetes patients.
DESIGN:
The Bergamo Nephrologic Diabetes Complications Trial-B was a multicentre, prospective, double-blind, parallel-group trial comparing renal and cardiovascular outcomes in 281 hypertensive type 2 diabetes patients with microalbuminuria randomized to at least 2-year VeraTran (verapamil/trandolapril 180 mg/2 mg daily) or trandolapril (2 mg daily, identical image) treatment. Main outcome was persistent macroalbuminuria (albuminuria >200 μg/min in two consecutive visits). Treatment targets were SBP/DBP less than 120/80 mmHg and HbA1C less than 7%.
RESULTS:
Over a median follow-up of 4.5 years, 18 patients (13%) on VeraTran vs. 15 (10.5%) on trandolapril [unadjusted hazard ratio (95% confidence interval [CI]) 1.07 (0.54-2.12), P = 0.852] progressed to macroalbuminuria, respectively; 62 (44.9%) vs. 71 (49.7%) [0.80 (0.57-1.12), P = 0.198] regressed to normoalbuminuria (urinary albumin excretion <20 μg/min), and 20 (14.5%) vs. 21 (14.7%) [hazard ratio 0.93 (0.50-1.72), P = 0.816] had major cardiovascular events. BP and metabolic control were similar between groups. Patients with cardiovascular events were significantly less [13 (9.8%) vs. 28 (18.9%), hazard ratio: 0.37 (0.19-0.71), P = 0.003] among those regressing to normoalbuminuria than those without regression. Difference was independent of treatment allocation and was significant also after adjusting for baseline characteristics [0.40 (0.20-0.79), P = 0.009], follow-up SBP [0.40 (0.20-0.80), P = 0.010] or DBP [0.36 (0.18-0.73), P = 0.004] BP or HbA1C [0.43 (0.21-0.88), P = 0.021].
CONCLUSION:
In hypertensive type 2 diabetes patients with microalbuminuria, verapamil added-on trandolapril did not improve renal or cardiovascular outcomes. Independent of verapamil, trandolapril normalized albuminuria in half of patients and this translated into significant cardioprotection
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