Lipid droplets (LD), triglycerides and sterol esters among them, are well known for their capacity as lipid storage organelles. Recently, they have emerged as critical cytoplasmic structures involved in numerous biological functions. LD storage is generated de novo by the cell and provides an energy reserve, lipid precursors, and cell protection.
View Article and Find Full Text PDFA set of new dihydroquinoline embelin derivatives was obtained from the reaction of the natural benzoquinone embelin () with anilines and aromatic aldehydes in the presence of AgOTf. The synthesis of these compounds involves the formation of a Knoevenagel adduct, followed by nucleophilic addition of aniline and subsequent electrocyclic ring closure. The scope of the reaction regarding the aldehydes and anilines was determined.
View Article and Find Full Text PDFDysregulated inflammasome activity, particularly of the NLRP3 inflammasome, is associated with the development of several inflammatory diseases. The study of molecules directly targeting NLRP3 is an emerging field in the discovery of new therapeutic compounds for the treatment of inflammatory disorders. Friedelane triterpenes are biologically active phytochemicals having a wide range of activities including anti-inflammatory effects.
View Article and Find Full Text PDFThe cardiovascular side effects associated with doxorubicin (DOX), a wide spectrum anticancer drug, have limited its clinical application. Therefore, to explore novel strategies with cardioprotective effects, a series of new labdane conjugates were prepared (6a-6c and 8a-8d) from the natural diterpene labdanodiol (1). These hybrid compounds contain anti-inflammatory privileged structures such as naphthalimide, naphthoquinone, and furanonaphthoquinone.
View Article and Find Full Text PDFDehydroisohispanolone (DIH), is a labdane diterpene that has exhibited anti-inflammatory activity via inhibition of NF-κB activation, although its potential effects on inflammasome activation remain unexplored. This study aims to elucidate whether DIH modulates NLR family pyrin domain-containing protein 3 (NLRP3) inflammasome in macrophages. Our findings show that DIH inhibited NLRP3 activation triggered by Nigericin (Nig), adenosine triphosphate (ATP) and monosodium urate (MSU) crystals, indicating broad inhibitory effects.
View Article and Find Full Text PDFThe NLRP3 inflammasome plays a critical role in inflammation-mediated human diseases and represents a promising drug target for novel anti-inflammatory therapies. Hispanolone is a labdane diterpenoid isolated from the aerial parts of species. This diterpenoid and some derivatives have demonstrated anti-inflammatory effects in classical inflammatory pathways.
View Article and Find Full Text PDFIncreasing evidence supports NLRP3 inflammasome as a new target to control inflammation. Dysregulation of NLRP3 inflammasome has been reported to be involved in the pathogenesis of several human inflammatory diseases. However, no NLRP3 inflammasome inhibitors are available in clinic.
View Article and Find Full Text PDFα-Hispanolol (α-H) is a labdane diterpenoid that has been shown to induce apoptosis in several human cancer cells. However, the effect of α-H in human glioblastoma cells has not been described. In the present work, we have investigated the effects of α-H on apoptosis, migration, and invasion of human glioblastoma cells with the aim of identifying the molecular targets underlying its mechanism of action.
View Article and Find Full Text PDFCalcium/Calcineurin/Nuclear Factor of Activated T cells (Ca/CN/NFAT) signalling pathway is the main calcium (Ca) dependent signalling pathway involved in the homeostasis of brain tissue. Here, we study the presence of NFATc members in human glioma by using U251 cells and a collection of primary human glioblastoma (hGB) cell lines. We show that NFATc3 member is the predominant member.
View Article and Find Full Text PDFA series of nine derivatives (⁻) were prepared from the diterpene solidagenone () and their structures were elucidated by means of spectroscopic studies. Their ability to inhibit inflammatory responses elicited in peritoneal macrophages by TLR ligands was investigated. Compounds and showed significant anti-inflammatory effects, as they inhibited the protein expression of nitric oxide synthase (NOS-2), cyclooxygenase-2 (COX-2), and cytokine production (TNF-α, IL-6, and IL-12) induced by the ligand of TLR4, lipopolysaccharide (LPS), acting at the transcriptional level.
View Article and Find Full Text PDFMacrophages are highly plastic cells that adopt different functional phenotypes in response to environmental signals. Classically activated macrophages (M1) exhibit a pro-inflammatory role, mediating host defense against microorganisms or tumor cells; whereas alternatively activated macrophages (M2) perform a range of physiological processes, including inflammation, wound repair and tissue remodeling. Interestingly, M2 macrophages have been involved in pathological settings such as tumor progression, parasitic infection and respiratory disorders.
View Article and Find Full Text PDFAnticancer Agents Med Chem
November 2019
Cancer continues to be one of the major causes of death worldwide. Despite many advances in the understanding of this complex disease, new approaches are needed to improve the efficacy of current therapeutic treatments against aggressive tumors. Natural products are one of the most consistently successful sources of drug leads.
View Article and Find Full Text PDFThe endothelial layer is essential for maintaining homeostasis in the body by controlling many different functions. Regulation of the inflammatory response by the endothelial layer is crucial to efficiently fight against harmful inputs and aid in the recovery of damaged areas. When the endothelial cells are exposed to an inflammatory environment, such as the outer component of gram-negative bacteria membrane, lipopolysaccharide (LPS), they express soluble pro-inflammatory cytokines, such as Ccl5, Cxcl1 and Cxcl10, and trigger the activation of circulating leukocytes.
View Article and Find Full Text PDFTumor microenvironment has been described to play a key role in tumor growth, progression, and metastasis. Macrophages are a major cellular constituent of the tumor stroma, and particularly tumor associated macrophages (TAMs or M2-like macrophages) exert important immunosuppressive activity and a pro-tumoral role within the tumor microenvironment. Alternative-reading frame (ARF) gene is widely inactivated in human cancer.
View Article and Find Full Text PDFEndothelial activation contributes to lung inflammatory disorders by inducing leucocyte recruitment to pulmonary parenchyma. Consequently, vascular-targeted therapies constitute promising strategies for the treatment of inflammatory pathologies. In the present study, we evaluated the effect of 8,9-dehydrohispanolone-15,16-lactol diterpene (DT) on lung endothelium during inflammation.
View Article and Find Full Text PDFA series of naphthoimidazoles derivatives (3a-3f) were tested for potential anti-inflammatory activity on lipopolysaccharide (LPS)-treated macrophages. Naphthoimidazole 3e exhibited significant inhibitory effects on nitric oxide (NO) production (IC50 <10μM) and decreased the expression of nitric oxide synthase-2 (NOS-2) and cycloxygenase-2 (COX-2) enzymes. It also inhibited the activation of transcription factor NF-κB.
View Article and Find Full Text PDFWe studied whether chemokines may have a role in relapses in childhood acute lymphoblastic leukemia (ALL). We compared the levels of chemokine receptors in marrow samples from 82 children with ALL at diagnosis versus 15 at relapses, and quantified the levels of chemokines in central system fluid (CSF) samples. The functional role of specific chemokines was studied in vitro and in vivo.
View Article and Find Full Text PDFHispanolone derivatives have been previously described as anti-inflammatory and antitumoral agents. However, their effects on overcoming Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) resistance remain to be elucidated. In this study, we analyzed the cytotoxic effects of the synthetic hispanolone derivative α-hispanolol (α-H) in several tumor cell lines, and we evaluated the induction of apoptosis, as well as the TRAIL-sensitizing potential of α-H in the hepatocellular carcinoma cell line HepG2.
View Article and Find Full Text PDFEthnopharmacological Relevance: Propolis has long been used as a popular folk medicine due to its wide spectrum of alleged biological and pharmaceutical properties. In Chile, propolis is widely used by folklore medicine as an anti-inflammatory agent; however, this property has not been demonstrated by scientific methods.
Aim Of The Study: The objective of this study was to determine the anti-inflammatory activity in vivo and in vitro and to establish the phenolic profile of propolis collected in two localities in Región Metropolitana de Santiago (RM), Chile.
Alternative activation of macrophages plays an important role in a range of physiological and pathological processes. This alternative phenotype, also known as M2 macrophages, is induced by type 2 cytokines such as IL-4. The binding of IL-4 to its receptor leads to activation of two major signaling pathways: STAT-6 and PI3K.
View Article and Find Full Text PDFIn the present study, a series of metallic complexes of the 1,4-naphthoquinone lawsone (2-6) were synthesized and evaluated for potential cytotoxicity in a mouse leukemic macrophagic RAW 264.7 cell line. Cell viability was determined by the MTT assay.
View Article and Find Full Text PDFThe interaction between tumor progression and innate immune system has been well established in the last years. Indeed, several lines of clinical evidence indicate that immune cells such as tumor-associated macrophages (TAMs) interact with tumor cells, favoring growth, angiogenesis, and metastasis of a variety of cancers. In most tumors, TAMs show properties of an alternative polarization phenotype (M2) characterized by the expression of a series of chemokines, cytokines, and proteases that promote immunosuppression, tumor proliferation, and spreading of the cancer cells.
View Article and Find Full Text PDFThe ARF locus is frequently inactivated in human cancer. The oncosuppressor ARF has indeed been described as a general sensor for different situation of cellular stress. We have previously demonstrated that ARF deficiency severely impairs inflammatory responses in vitro and in vivo, establishing a role for ARF in the regulation of innate immunity.
View Article and Find Full Text PDFARF (alternative reading frame) is one of the most important tumor regulator playing critical roles in controlling tumor initiation and progression. Recently, we have demonstrated a novel and unexpected role for ARF as modulator of inflammatory responses.
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