Immortalization of MEF is characterized by the deregulation of specific miRNAs with potential tumor suppressor activity

The life span (Hayflick limit) of primary mouse embryo fibroblasts (MEF) in culture is variable but it is still unclear if the escape of the Hayflick limit is also variable. To address this point MEF were expanded every fifteen days (6T15) instead of every three days (6T3) until they became immortal. With this protocol MEF lifespan was extended and immortalization accordingly delayed. By testing a panel of genes (p19ARF, p16, p21) and miRNAs (miR-20a, miR-21, miR-28, miR-290) related to primary MEF senescence, a switch of p21 from up to down regulation, the down regulation of specific miRNAs as well as a massive shift from diploidy to hyperdiploidy were observed in coincidence with the resumption of cell proliferation. Collectively, these data indicate that the inactivation of genes and miRNAs, important in controlling cell proliferation, might be determinant for the escape from the Hayflick limit. In support of this hypothesis was the finding that some of the down regulated miRNAs transfected in immortalized MEF inhibited cell proliferation thus displaying a tumor suppressor-like activity

Immortalized mouse embryo fibroblasts are resistant to miR-290-induced senescence regardless of p53 status

Immortalized mouse embryo fibroblasts are resistant to miR-290-induced senescence regardless of p53 status. Physiol Genomics 43: 1153-1159, 2011. First published August 16, 2011; doi:10.1152/physiolgenomics.00064.2011.-The prosenescence role of miR-290 and nocodazole has been documented in primary mouse embryo fibroblasts (MEF), while it is not clear whether immortal murine fibroblasts are still responsive to these senescence inducing stimuli. To establish this point, immortal murine fibroblasts with functional (NIH3T3) or nonfunctional p53 (I-MEF) and low levels of miR-290 were tested for their capability to undergo senescence after exposure to either nocodazole or miR-290. Our results clearly indicate that nocodazole induces senescence only in NIH3T3 cells with a functional p53 but not in I-MEF lacking a functional p53. miR-290 overexpression is unable to address any of the tested immortalized clones toward senescence, regardless of the p53 status, suggesting that the prosenescence role of miR-290 is specific for primary but not for immortal murine fibroblasts. Moreover our findings suggest that the mere downregulation of a potential tumor suppressor miRNA in a given cell type does not necessarily imply that it behaves as a tumor suppressor

The zebrafish/tumor xenograft angiogenesis assay as a tool for screening anti-angiogenic miRNAs

The zebrafish/tumor xenograft angiogenesis assay is used to approach tumor angiogenesis, a pivotal step in cancer progression and target for anti-tumor therapies. Here, we evaluated whether the assay could allow the identification of microRNAs having an anti-angiogenic potential. For that, we transfected DU-145 prostate cancer cells with four microRNAs (miR-125a, miR-320, miR-487b, miR-492) responsive to both anti- and pro-angiogenic stimuli applied to human umbilical vein endothelial cells. After transfection, DU-145 cells were injected close to the developing subintestinal vessels of transgenic Tg(Kdrl:eGFP)s843 zebrafish embryos that express green fluorescent protein under the control of Kdrl promoter. At 72 h post-fertilization, we observed that green fluorescent protein–positive neo-vessels infiltrated the graft of DU-145 transfected with miR-125a, miR-320, and miR-487b. Vice versa, neo-vessel formation and tumor cell infiltration were inhibited when DU-145 cells transfected with miR-492 were used. These results indicated that the zebrafish/tumor xenograft assay was adequate to identify microRNAs able to suppress the release of angiogenic growth factors by angiogenic tumor cells

On the importance of anandamide structural features for its interactions with DPPC bilayers: effects on PLA2 activity

The acylethanolamide anandamide (AEA) occurs in a variety of mammalian tissues and, as a result of its action on cannabinoid receptors, exhibits several cannabimimetic activities. Moreover, some of its effects are mediated through interaction with an ion channel-type vanilloid receptor. However, the chemical features of AEA suggest that some of its biological effects could be related to physical interactions with the lipidic part of the membrane. The present work studies the effect of AEA-induced structural modifications of the dipalmitoylphosphatidylcholine (DPPC) bilayer on phospholipase A2 (PLA2) activity, which is strictly dependent on lipid bilayer features. This study, performed by 2-dimethylamino-(6-lauroyl)-naphthalene fluorescence, demonstrates that the effect of AEA on PLA2 activity is concentration-dependent. In fact, at low AEA/DPPC molar ratios (from R = 0.001 to R = 0.04), there is an increase of the enzymatic activity, which is completely inhibited for R = 0.1. X-ray diffraction data indicate that the AEA affects DPPC membrane structural properties in a concentration-dependent manner. Because the biphasic effect of increasing AEA concentrations on PLA2 activity is related to the induced modifications of membrane bilayer structural properties, we suggest that AEA-phospholipid interactions may be important to produce, at least in part, some of the similarly biphasic responses of some physiological activities to increasing concentrations of AEA

Kidney dysfunction is associated with adverse outcomes in internal medicine COVID-19 hospitalized patients

OBJECTIVE: In this study, we aimed to evaluate the kidney involvement as-sessed by estimated glomerular filtration rate (eGFR), the associations with specific clinical disease variables and laboratory findings, and the predictive role of eGFR on clinical outcomes of patients admitted with COVID-19 in Internal Medicine ward in the first wave. PATIENTS AND METHODS: Clinical data of 162 consecutive patients hospitalized in the University Hospital Policlinico Umberto I in Rome, Italy, between December 2020 to May 2021 were collected and retrospectively analyzed. RESULTS: The median eGFR was significantly lower in patients with worse outcomes than in patients with favorable outcomes [56.64 ml/min/1.73 m2 (IQR 32.27-89.73) vs. 83.39 ml/min/1.73 m2 (IQR 69.59-97.08), p<0.001]. Patients with eGFR < 60 ml/ min/1.73 m(2) (n=38) were significantly older com-pared to patients with normal eGFR [82 years (IQR 74-90) vs. 61 years (IQR 53-74), p<0.001] and they had fever less frequently [39.5% vs. 64.2%, p<0.01]. Kaplan-Meier curves demonstrated that over-all survival was significantly shorter in patients with eGFR < 60 ml/min/1.73 m(2) (p<0.001). In mul-tivariate analysis, only eGFR < 60 ml/min/1.73 m2 [HR=2.915 (95% CI=1.110-7.659), p<0.05] and plate-let to lymphocyte ratio [HR=1.004 (95% CI=1.002-1.007), p<0.01] showed a significant predictive val-ue for death or transfer to intensive care unit (ICU). CONCLUSIONS: Kidney involvement on ad-mission was an independent predictor for death or transfer to ICU among hospitalized COVID-19 patients. The presence of chronic kidney dis-ease could be regarded as a relevant factor in risk stratification for COVID-19

A Novel Study and Meta-Analysis of the Genetic Variation of the Serotonin Transporter Promoter in the Italian Population Do Not Support a Large Effect on Alzheimer's Disease Risk

Alzheimer's disease (AD) is a neurodegenerative disorder whose clinical onset is mainly characterized by memory loss. During AD progression, behavioral and psychological symptoms of dementia (BPSD) frequently occur. In this paper we evaluated the association between AD and the short/long (S/L) functional polymorphism of the promoter region of the 5-hydroxytryptamine (5-HT) transporter gene (SLC6A4). The S-allele shows a 2-fold reduced transcriptional rate, causing an imbalance in 5-HT intracellular availability that might in turn trigger behavioral and cognitive alterations. We also genotyped the SLC6A4 promoter functional variant rs25531 (A → G). By comparing the genotypic and allelic frequencies in an Italian population of 235 AD and 207 controls, we found an association between 5-HTTLPR and AD (odds ratio for the L-allele versus the S-allele: 0.74, associated P value = .03), while no difference was found for the rs25531. A meta-analysis of studies in Italy assessing 5-HTTLPR and AD risk gave an estimation of odds ratio for the L-allele versus the S-allele of 0.85 (associated P value = .08). Overall, our findings are not supportive of a large genetic effect of the explored polymorphisms on AD risk

Variables influencing executive functioning in preschool hearing-impaired children implanted within 24 months of age: an observational cohort study

Executive Functions (EFs) are fundamental to every aspect of life. The present study was implemented to evaluate factors influencing their development in a group of preschools orally educated profoundly deaf children of hearing parents, who received CI within two years of age. Methods Twenty-five preschool CI children were tested using the Battery for Assessment of Executive Functions (BAFE) to assess their flexibility, inhibition and non-verbal visuo-spatial working memory skills. The percentage of children performing in normal range was reported for each of the EF subtests. Mann-Whitney and Kruskal-Wallis were performed to assess differences between gender, listening mode and degree of parents’ education subgroups. The Spearman Rank Correlation Coefficient was calculated to investigate the relationship between EF scores audiological and linguistic variables. Results Percentages ranging from 76% to 92% of the children reached adequate EF scores at BAFE. Significant relations (p<0.05) were found between EFs and early intervention, listening and linguistic skills. Further, CI children from families with higher education level performed better at the response shifting, inhibitory control and attention flexibility tasks. Economic income correlated significantly with flexibility and inhibitory skills. Females performed better than males only in the attention flexibility task. Conclusions The present study is one of the first to focus attention on the development of EFs in preschool CI children, providing an initial understanding of the characteristics of EFs at the age when these skills emerge. Clinical practice must pay increasing attention to these aspects which are becoming the new emerging challenge of rehabilitation programs

The Proto-Oncogene LRF Is under Post-Transcriptional Control of MiR-20a: Implications for Senescence

MicroRNAs (miRNAs) are short 20–22 nucleotide RNA molecules that act as negative regulators of gene expression via translational repression: they have been shown to play a role in development, proliferation, stress response, and apoptosis. The transcriptional regulator LRF (Leukemia/lymphoma Related Factor) has been shown to prevent p19ARF transcription and consequently to inhibit senescence in mouse embryonic fibroblasts (MEF). Here we report, for the first time, that LRF is post-transcriptionally regulated by miR-20a. Using a gene reporter assay, direct interaction of miR-20a with the LRF 3′UTR is demonstrated. To validate the interaction miR-20a/3′UTR LRF miR-20a was over-expressed, either by transient transfection or retroviral infection, in wild type mouse embryo fibroblasts and in LRF-null MEF derived from LRF knock-out mice. We observed LRF decrease, p19ARF increase, inhibition of cell proliferation and induction of senescence. The comparison of miR-20a activity in wt and LRF-null MEF indicates that LRF is the main mediator of the miR-20a-induced senescence and that other targets are cooperating. As LRF down-regulation/p19ARF induction is always accompanied by E2F1 down-regulation and increase of p16, we propose that all these events act in synergy to accomplish miR-20a-induced senescence in MEF. Senescence has been recently revaluated as a tumor suppressor mechanism, alternative to apoptosis; from this point of view the discovery of new physiological “senescence inducer” appears to be promising as this molecule could be used as anticancer drug

Monitoraggio Ambientale di un'Area Contaminata nella Provincia di Pavia

Lo scopo di tale indagine è stato quello di valutare il livello di contaminazione, l'estensione e l'entità di contaminanti presenti nei suoli superficiali a suo tempo riscontrati mediante il Progetto Pavia. Il monitoraggio ambientale ha interessato un'area di circa 12 ettari che si trova nel comune di Carpiano. Complessivamente sono state identificate 33 aree di campionamento dove sono stati prelevati campioni di suolo sino alla profondità di 30 cm. In ciascun campione di suolo, dopo adeguati trattamenti, è stata valutata la concentrazione di metalli pesanti, metalloidi, macroelementi, sostanza organica, pH, densità apparente, contenuto d'acqua. In alcuni campioni, precisamente 11, si è analizzata la concentrazione di diossine e furani e si è approntato uno studio che ha visto l'utilizzo dei batteri e dei loro prodotti. Lo studio condotto attraverso l'uso dei batteri ha evidenziato anomalie in alcuni punti ad elevata contaminazione. I risultati analitici ottenuti hanno identificato la presenza di una importante contaminazione di metalli pesanti, metalloidi, diossine e furani che interessa un area di alcuni ettari. Tale livello di contaminazione, per la presenza di sostanza organica e per valori ridotti di acidità dei suoli stessi, potrà arrecare danni ingenti all'ambiente.JRC.DDG.H.7-Land management and natural hazard

Impact of proanthocyanidin-rich apple intake on gut microbiota composition and polyphenol metabolomic activity in healthy mildly hypercholesterolemic subjects

AbstractApples are a rich source of polyphenols and fiber. Proanthocyanidins (PAs), the largest polyphenolic class in apples, can reach the colon almost intact where they interact with the gut microbiota producing simple phenolic acids. These metabolites have the potential to modulate gut microbiota composition and activity and impact on host physiology. A randomized, controlled, crossover, dietary intervention study was performed to determine the broad effects of whole apple intake on fecal gut microbiota composition and activity. Forty heathy mildly hypercholesterolemic volunteers (23 women, 17 men), with a mean BMI (± SD) 25.3 ± 3.7 kg/m2 and age 51 ± 11 years, consumed 2 apples/day (Renetta Canada, rich in PAs), or a sugar matched control apple beverage, for 8 weeks separated by a 4-week washout period in a random order. Fecal and 24-h urine samples were collected before and after each treatment. The broad effects of apple intake on fecal gut microbiota composition were explored by the high throughput sequencing (HTS) of 16S rRNA gene lllumina MiSeq sequencing (V3-V4 region). Sequencing data analysis was performed using the Quantitative Insight Into Microbial Ecology (QIIME) open-source pipeline version 1.9.1. Specific bacterial groups were also enumerated using the quantitative Fluorescence In Situ Hybridization (FISH). Furthermore, the potential formation of microbial polyphenol metabolites, after apple intake, was explored in urine using Liquid Chromatography (LC) High-Resolution Mass Spectrometry (HRMS) metabolomics. Preliminary analysis showed no changes in gut microbiota abundances measured by Illumina MiSeq, after correction for multiple testing. Apple intake significantly decreased Enterobacteriaceae population (P = 0.04) compared to the control beverage, as determined with FISH. Twenty-four polyphenol microbial metabolites were identified in higher concentrations in the apple group (P < 0.05) compared to the control, including valerolactones, valeric and phenolic acids. In conclusion, preliminary data suggest that the daily intake of 2 Renetta Canada apples significantly decreased Enterobacteriaceae population, a family known for its pathogenic members, in healthy mildly hypercholesterolemic subjects. Moreover, several polyphenol microbial metabolites were identified, suggesting that microbial activity is crucial and a prerequisite for the absorption of apple polyphenols, producing active metabolites with potential health benefits