Divergent regulation of long non-coding RNAs H19 and PURPL affects cell senescence in human dermal fibroblasts.

Cellular senescence is a permanent cell growth arrest that occurs in response to various intrinsic and extrinsic stimuli and is associated with cellular and molecular changes. Long non-coding RNAs (lncRNAs) are key regulators of cellular senescence by affecting the expression of many important genes involved in senescence-associated pathways and processes. Here, we evaluated a panel of lncRNAs associated with senescence for their differential expression between young and senescent human dermal fibroblasts (NHDFs) and studied the effect of a known senomorphic compound, resveratrol, on the expression of lncRNAs in senescent NHDFs.

Olive phenols preserve lamin B1 expression reducing cGAS/STING/NFκB-mediated SASP in ionizing radiation-induced senescence.

Senescence occurs upon critical telomere shortening, or following DNA damage, oncogenic activation, hypoxia and oxidative stress, overall referred to stress-induced premature senescence (SIPS). In response to DNA damage, senescent cells release cytoplasmic chromatin fragments (CCFs), and express an altered secretome, the senescence-associated secretory phenotype (SASP), which contributes to generate a pro-inflammatory and pro-tumoral extracellular milieu. Polyphenols have gained significant attention owing to their anti-inflammatory and anti-tumour activities.

Parvovirus B19 induces cellular senescence in human dermal fibroblasts: putative role in systemic sclerosis-associated fibrosis.

Objective: Emerging evidence demonstrates that excessive accumulation of senescent cells is associated with some chronic diseases and suggests a pathogenic role of cellular senescence in fibrotic processes, such as that occurring in ageing or in SSc. Recently we demonstrated that parvovirus B19 (B19V) activates normal human dermal fibroblasts and induces expression of different profibrotic/pro-inflammatory genes. This observation prompted us to investigate whether it is also able to induce fibroblast senescence as a potential pathogenetic mechanism in B19V-induced fibrosis.

Colon fibroblasts from Pirc rats (F344/NTac-Apc ) exhibit a proliferative and inflammatory phenotype that could support early stages of colon carcinogenesis.

The role of fibroblast APC mutation in carcinogenesis is not clear. Apc colon fibroblasts have been previously characterized: however, little is known about their behavior at very early-stage of colon carcinogenesis. We cultured colon mucosa fibroblasts (PCF, Apc ) of Pirc rats (F344/NTac-Apc ) at an early stage of tumorigenesis, in absence of preneoplastic lesions, and of age-matched wt (WCF): DNA damage levels, inflammatory phenotype and the expression of known markers of CAFs were analyzed.

Enhanced Antitumoral Activity and Photoacoustic Imaging Properties of AuNP-Enriched Endothelial Colony Forming Cells on Melanoma.

Near infrared (NIR)-resonant gold nanoparticles (AuNPs) hold great promise in cancer diagnostics and treatment. However, translating the theranostic potential of AuNPs into clinical applications still remains a challenge due to the difficulty to improve the efficiency and specificity of tumor delivery in vivo as well as the clearance from liver and spleen to avoid off target toxicity. In this study, endothelial colony forming cells (ECFCs) are exploited as vehicles to deliver AuNPs to tumors.

uPAR-expressing melanoma exosomes promote angiogenesis by VE-Cadherin, EGFR and uPAR overexpression and rise of ERK1,2 signaling in endothelial cells.

Exosomes (Exos) have been reported to promote pre-metastatic niche formation, proliferation, angiogenesis and metastasis. We have investigated the role of uPAR in melanoma cell lines-derived Exos and their pro-angiogenic effects on human microvascular endothelial cells (HMVECs) and endothelial colony-forming cells (ECFCs). Melanoma Exos were isolated from conditioned media of A375 and M6 cells by differential centrifugation and filtration.

Inhibition of 37/67kDa Laminin-1 Receptor Restores APP Maturation and Reduces Amyloid-β in Human Skin Fibroblasts from Familial Alzheimer's Disease.

Alzheimer's disease (AD) is a fatal neurodegenerative disorder caused by protein misfolding and aggregation, affecting brain function and causing dementia. Amyloid beta (Aβ), a peptide deriving from amyloid precursor protein (APP) cleavage by-and γ-secretases, is considered a pathological hallmark of AD. Our previous study, together with several lines of evidence, identified a strict link between APP, Aβ and 37/67kDa laminin receptor (LR), finding the possibility to regulate intracellular APP localization and maturation through modulation of the receptor.

Chronic Resveratrol Treatment Reduces the Pro-angiogenic Effect of Human Fibroblast "Senescent-Associated Secretory Phenotype" on Endothelial Colony-Forming Cells: The Role of IL8.

Senescent cells are characterized by an increased secretion of inflammatory and growth factors, known as the "senescence-associated secretory phenotype" (SASP), producing a pro-tumoral and pro-angiogenic microenvironment. This work proposes chronic resveratrol treatment (5 µM for 5 weeks, termed R5) of senescent MRC5 fibroblasts as a mean to mimic and target the angiogenic trait of stromal fibroblast SASP. Senescent fibroblast conditioned medium (CM sen) was effective in enhancing the angiogenic properties of endothelial colony-forming cells (ECFCs), that is, invasive activity and capillary morphogenesis capability in vitro, that were significantly reduced when conditioned media were collected after resveratrol pretreatment (CM senR5).

Serpin A1 and the modulation of type I collagen turnover: Effect of the C-terminal peptide 409-418 (SA1-III) in human dermal fibroblasts.

The pharmacological modulation of collagen turnover is a strategy potentially useful in different skin conditions. The serine protease inhibitor Serpin A1 and portions of its C-terminal region have been investigated as collagen modulators. To clarify the mechanisms by which the C-terminal 409-418 peptide SA1-III increases extracellular type I collagen levels, to compare its activities range with that of the originator molecule Serpin A1, and to evaluate its efficacy in primary cultures from adult and aged human subjects.

Modulation of the Senescence-Associated Inflammatory Phenotype in Human Fibroblasts by Olive Phenols.

Senescent cells display an increase in the secretion of growth factors, inflammatory cytokines and proteolytic enzymes, termed the "senescence-associated-secretory-phenotype" (SASP), playing a major role in many age-related diseases. The phenolic compounds present in extra-virgin olive oil are inhibitors of oxidative damage and have been reported to play a protective role in inflammation-related diseases. Particularly, hydroxytyrosol and oleuropein are the most abundant and more extensively studied.

uPA/uPAR system activation drives a glycolytic phenotype in melanoma cells.

In this manuscript, we show the involvement of the uPA/uPAR system in the regulation of aerobic glycolysis of melanoma cells. uPAR over-expression in human melanoma cells controls an invasive and glycolytic phenotype in normoxic conditions. uPAR down-regulation by siRNA or its uncoupling from integrins, and hence from integrin-linked tyrosine kinase receptors (IL-TKRs), by an antagonist peptide induced a striking inhibition of the PI3K/AKT/mTOR/HIF1α pathway, resulting into impairment of glucose uptake, decrease of several glycolytic enzymes and of PKM2, a checkpoint that controls metabolism of cancer cells.

Chronic Resveratrol Treatment Inhibits MRC5 Fibroblast SASP-Related Protumoral Effects on Melanoma Cells.

Cellular senescence is related to organismal aging and is observed after DNA damaging cancer therapies, that induce tumor-suppressive modifications, but it is characterized by a strong increase in secreted factors, termed the "senescence-associated secretory phenotype" (SASP). Particularly, SASP from stroma senescent fibroblasts creates a cancer-favoring microenvironment, providing targets for anti-cancer interventions. In the present article, chronic treatment (5 weeks) with 5 µM resveratrol has been used to modulate senescence-related protumoral features of MRC5 fibroblasts, reducing SASP-related interleukins IL1α, IL1β, IL6, and IL8; transforming-growth-factor-β (TGFβ); matrix metallo-proteinases MMP3 and MMP2; urokinase plasminogen activator (uPA); receptor proteins uPAR, IL6R, insulin growth factor receptor-1 (IGF-1R), TGFβ-R2, and CXCR4.

The pro-healing effect of exendin-4 on wounds produced by abrasion in normoglycemic mice.

Experimental evidence suggested that Exendin-4 (Exe4), an agonist at glucagon like receptor-1 (GLP-1R), promoted tissue regeneration. We aimed to verify the effect of Exe4, in the absence or in the presence of Exendin-4(9-39), an antagonist at GLP-1R, on the healing of abraded skin. Two wounds (approximately 1.

Altered proteolysis in fibroblasts of Alzheimer patients with predictive implications for subjects at risk of disease.

There is great interest in developing reliable biomarkers to support antemortem diagnosis of late-onset Alzheimer's disease (AD). Early prediction and diagnosis of AD might be improved by the detection of a proteolytic dysfunction in extracts from cultured AD fibroblasts, producing altered isoelectrophoretic forms of the enzyme transketolase (TK-alkaline bands). The TK profile and apolipoprotein E (APOE) genotype were examined in fibroblasts from 36 clinically diagnosed probable late-onset sporadic AD patients and 38 of their asymptomatic relatives, 29 elderly healthy individuals, 12 neurological non-AD patients, and 5 early-onset AD patients.

Chronic resveratrol treatment ameliorates cell adhesion and mitigates the inflammatory phenotype in senescent human fibroblasts.

We evaluated the effect of resveratrol on the senescence-associated secretory phenotype (SASP) and on adhesion-related processes in cultured human MRC5 fibroblasts. Presenescent cultures were chronically treated with or without 5 µM resveratrol. The development of SASP in MRC5 fibroblasts approaching senescence was significantly attenuated by resveratrol treatment, which reduced both gene expression and release of proinflammatory cytokines.

Cholesterol esterification during differentiation of mouse erythroleukemia (Friend) cells.

Cholesterol is an essential constituent of all mammalian cell membranes and its availability is therefore a prerequisite for cellular growth and other functions. Several lines of evidence are now indicating an association between alterations of cholesterol homeostasis and cell cycle progression. However, the role of cholesterol in cell differentiation is still largely unknown.

Protective effects of resveratrol against senescence-associated changes in cultured human fibroblasts.

Recent research has focused on natural compounds possibly endowed with antiaging effects. Resveratrol is a stilbene compound produced by different plants with many biologic activities, including an antiaging effect, which has been demonstrated both in vitro in eukaryotic cells and in vivo in mice. We studied the effect of resveratrol on cultured human MRC5 fibroblasts, a widely used in vitro model in aging studies.

Accumulation of neutral lipids in peripheral blood mononuclear cells as a distinctive trait of Alzheimer patients and asymptomatic subjects at risk of disease.

Background: Alzheimer's disease is the most common progressive neurodegenerative disease. In recent years, numerous progresses in the discovery of novel Alzheimer's disease molecular biomarkers in brain as well as in biological fluids have been made. Among them, those involving lipid metabolism are emerging as potential candidates.

Altered cholesterol ester cycle in skin fibroblasts from patients with Alzheimer's disease.

Intracellular cholesterol metabolism was reported to modulate amyloid-beta (Abeta) generation in Alzheimer's disease (AD). Results presented herein demonstrated that, like brain cells, cultured skin fibroblasts from AD patients contained more cholesterol esters than fibroblasts from healthy subjects. Particularly, Oil Red-O, Nile Red, and filipin staining highlighted higher levels of neutral lipids which responded to inhibitors of acyl-coenzyme A:cholesterol acyl-transferase (ACAT-1), associated with an increase in free cholesterol.

The comet assay approach to senescent human diploid fibroblasts identifies different phenotypes and clarifies relationships among nuclear size, DNA content, and DNA damage.

The comet assay methodology was used to monitor nuclear changes occurring in MRC5 human fibroblasts during transition from young to senescent cultures and to study heterogeneity of senescent populations. Nuclear morphology and size, DNA content per nucleus, and DNA damage (basal strand break, total damage, and oxidized base levels) were evaluated; moreover, visually identified large and small nuclei were analyzed separately and arranged in classes of increasing DNA damage. Oxidized base levels were definitely lower in young versus senescent fibroblasts of which, however, a significant proportion showed negligible DNA damage.

Increased plasma levels of soluble CD40, together with the decrease of TGF beta 1, as possible differential markers of Alzheimer disease.

Alzheimer's disease (AD) is a progressive neurodegenerative illness and the most frequent cause of dementia in the elderly. The identification of activated microglia within neuritic plaques, coupled with the presence of numerous inflammatory proteins, suggests that inflammation is an integral part of the pathogenetic process in AD. In the present paper we have investigated the levels of circulating inflammatory mediators as potential AD biomarkers concentrating essentially on (a) soluble CD40 (sCD40), a member of the tumor necrosis factor receptor superfamily lacking the membrane-associated endodomain by alternative splicing, and (b) transforming growth factor (TGF)-beta 1, a cytokine deeply involved in AD and playing a protective role on CNS.

Comparative levels of DNA breaks and sensitivity to oxidative stress in aged and senescent human fibroblasts: a distinctive pattern for centenarians.

Basal and H(2)O(2)-induced DNA breaks as well as DNA repair activity and efficacy of the antioxygenic system were determined in human dermal fibroblasts explanted from either (i) young donors and passaged serially to reach replicative senescence or (ii) young, old and centenarian donors and shortly propagated in culture. These fibroblasts have been employed as an in vitro and ex vivo model, respectively, to evaluate comparatively DNA integrity during senescence (increasing population doubling levels) and aging (increasing donor age). Constitutive levels of DNA total strand breaks, as determined by the alkaline extraction procedure, changed moderately among the different cell lines, which exhibited, however, significant differences in the amount of either single or double strand breaks.

A cystatin-based affinity procedure for the isolation and analysis of papain-like cysteine proteinases from tissue extracts.

Cysteine-proteinases (CP) of the papain family can be affinity-adsorbed by egg white cystatin C coupled to Sepharose 4B, thus allowing their selective isolation from either tissue or cultured cell extracts as well as biolological fluids and culture media. CP complexed by immobilized cystatin are further analyzed by means of SDS-PAGE and Western blot followed by serial or parallel immunological detection. The single-step affinity adsorption of papain-like enzymes has the advantage, over immunoprecipitation techniques, of yielding the simultaneous and comprehensive picture of most CP, as both precursor and mature forms, in a given sample.