Type 2 diabetes mellitus (T2DM) is a metabolic disorder that has reached epidemic proportions worldwide, posing a huge treat on people's health and quality of life. From a pathogenetic prospective, T2DM is driven by insulin resistance defined as a blunted response of tissues to insulin which leads to chronic hyperglycaemia. Mechanistically, lipotoxicity and particularly the intracellular accumulation of ceramides in the skeletal muscle and the liver, is a primary metabolic aberration underpinning insulin resistance.
View Article and Find Full Text PDFThe human retina is a complex anatomical structure that has no regenerative capacity. The pathogenesis of most retinopathies can be attributed to inflammation, with the activation of the inflammasome protein platform, and to the impact of oxidative stress on the regulation of apoptosis and autophagy/mitophagy in retinal cells. In recent years, new therapeutic approaches to treat retinopathies have been investigated.
View Article and Find Full Text PDFThe SARS-CoV-2 outbreak has infected a vast population across the world, causing more than 664 million cases and 6.7 million deaths by January 2023. Vaccination has been effective in reducing the most critical aftermath of this infection, but some issues are still present regarding re-infection prevention, effectiveness against variants, vaccine hesitancy and worldwide accessibility.
View Article and Find Full Text PDFThe retina, the part of the eye, translates the light signal into an electric current that can be sent to the brain as visual information. To achieve this, the retina requires fine-tuned vascularization for its energy supply. Diabetic retinopathy (DR) causes alterations in the eye vascularization that reduce the oxygen supply with consequent retinal neurodegeneration.
View Article and Find Full Text PDFEpigenetics encompasses a group of dynamic, reversible, and heritable modifications that occur within cells that are independent of gene mutations. These alterations are highly influenced by the environment, from the environment that surrounds the human being to the internal microenvironments located within tissues and cells. The ways that pigenetic modifications promote the initiation of the tumorigenic process have been widely demonstrated.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
June 2021
Multiple sclerosis (MS) is a neuroinflammatory and neurodegenerative disease characterized by myelin damage followed by axonal and ultimately neuronal loss. The etiology and physiopathology of MS are still elusive, and no fully effective therapy is yet available. We investigated the role in MS of autophagy (physiologically, a controlled intracellular pathway regulating the degradation of cellular components) and of mitophagy (a specific form of autophagy that removes dysfunctional mitochondria).
View Article and Find Full Text PDFMitochondria are dynamic organelles that participate in a broad array of molecular functions within the cell. They are responsible for maintaining the appropriate energetic levels and control the cellular homeostasis throughout the generation of intermediary metabolites. Preserving a healthy and functional mitochondrial population is of fundamental importance throughout the life of the cells under pathophysiological conditions.
View Article and Find Full Text PDFDuring the past few decades, considerable efforts have been made to discover and validate new molecular mechanisms and biomarkers of neurodegenerative diseases. Recent discoveries have demonstrated how autophagy and its specialized form mitophagy are extensively associated with the development, maintenance, and progression of several neurodegenerative diseases. These mechanisms play a pivotal role in the homeostasis of neural cells and are responsible for the clearance of intracellular aggregates and misfolded proteins and the turnover of organelles, in particular, mitochondria.
View Article and Find Full Text PDFCalcium (Ca) is a major second messenger in cells and is essential for the fate and survival of all higher organisms. Different Ca channels, pumps, or exchangers regulate variations in the duration and levels of intracellular Ca, which may be transient or sustained. These changes are then decoded by an elaborate toolkit of Ca-sensors, which translate Ca signal to intracellular operational cell machinery, thereby regulating numerous Ca-dependent physiological processes.
View Article and Find Full Text PDFBreast cancer (BC) represents the most common cancer in women worldwide. Due to its heterogeneous nature, breast cancer management might benefit from differential treatments toward personalized medicine. Additionally, drug resistance is a common phenomenon.
View Article and Find Full Text PDFCutaneous melanoma (CM) is a malignancy with increasing occurrence. Its microRNA repertoire has been defined in a number studies, leading to candidates for biological and clinical relevance: miR-200a/b/c, miR-203, miR-205, miR-204, miR-211, miR-23b and miR-26a/b. Our work was aimed to validate the role of these candidate miRNAs in melanoma, using additional patients cohorts and in vitro cultures.
View Article and Find Full Text PDFThe endoplasmic reticulum (ER) and mitochondria are tightly associated with very dynamic platforms termed mitochondria-associated membranes (MAMs). MAMs provide an excellent scaffold for crosstalk between the ER and mitochondria and play a pivotal role in different signaling pathways that allow rapid exchange of biological molecules to maintain cellular health. However, dysfunctions in the ER-mitochondria architecture are associated with pathological conditions and human diseases.
View Article and Find Full Text PDFInter-organelle membrane contact sites are emerging as major sites for the regulation of intracellular Ca concentration and distribution. Here, extracellular stimuli operate on a wide array of channels, pumps, and ion exchangers to redistribute intracellular Ca among several compartments. The resulting highly defined spatial and temporal patterns of Ca movement can be used to elicit specific cellular responses, including cell proliferation, migration, or death.
View Article and Find Full Text PDFOf skin cancers, 9% arise at the periocular level, constituting a significant threat due to the proximity to intracranial structures, such as the eyes, nerve endings and proximal tissues. Tumour recurrence can be frequent and represents a primary clinical challenge for the surgeon. To present a retrospective study on the treatment of eyelid tumours at a tertiary care centre in Italy over an eight-year period and, in particular, to underline the risk factors associated with tumour relapse.
View Article and Find Full Text PDFUntil 1972, the term 'apoptosis' was used to differentiate the programmed cell death that naturally occurs in organismal development from the acute tissue death referred to as necrosis. Many studies on cell death and programmed cell death have been published and most are, at least to some degree, related to cancer. Some key proteins and molecular pathways implicated in cell death have been analyzed, whereas others are still being actively researched; therefore, an increasing number of cellular compartments and organelles are being implicated in cell death and cancer.
View Article and Find Full Text PDFBiochim Biophys Acta Mol Cell Res
June 2017
Mitochondria-associated membranes are juxtaposed between the endoplasmic reticulum and mitochondria and have been identified as a critical hub in the regulation of apoptosis and tumor growth. One key function of mitochondria-associated membranes is to provide asylum to a number of proteins with tumor suppressor and oncogenic properties. In this review, we discuss how Ca flux manipulation represents the primary mechanism underlying the action of several oncogenes and tumor-suppressor genes and how these networks might be manipulated to provide novel therapies for cancer.
View Article and Find Full Text PDFOver the last few decades, many different groups have been engaged in studies of new roles for mitochondria, particularly the coupling of alterations in the redox pathway with the inflammatory responses involved in different diseases, including Alzheimer's disease, Parkinson's disease, atherosclerosis, cerebral cavernous malformations, cystic fibrosis and cancer. Mitochondrial dysfunction is important in these pathological conditions, suggesting a pivotal role for mitochondria in the coordination of pro-inflammatory signaling from the cytosol and signaling from other subcellular organelles. In this regard, mitochondrial reactive oxygen species are emerging as perfect liaisons that can trigger the assembly and successive activation of large caspase-1- activating complexes known as inflammasomes.
View Article and Find Full Text PDFBackground: The purpose of this study is to determine whether microRNA for pluripotent stem cells are also expressed in breast cancer and are associated with metastasis and outcome.
Methods: We studied global microRNA profiles during differentiation of human embryonic stem cells (n =26) and in breast cancer patients (n = 33) and human cell lines (n = 35). Using in situ hybridization, we then investigated MIR302 expression in 318 untreated breast cancer patients (test cohort, n = 22 and validation cohort, n = 296).
For many years breast cancer classification has been based on histology and immune-histochemistry. New techniques, more strictly related to cancer biology, partially succeeded in fractionating patients, correlated to survival and better predicted the patient response to therapy. Nowadays, great expectations arise from massive parallel or high throughput next generation sequencing.
View Article and Find Full Text PDFWe studied miRNA profiles in 4419 human samples (3312 neoplastic, 1107 nonmalignant), corresponding to 50 normal tissues and 51 cancer types. The complexity of our database enabled us to perform a detailed analysis of microRNA (miRNA) activities. We inferred genetic networks from miRNA expression in normal tissues and cancer.
View Article and Find Full Text PDFThe features of neuronal damage induced by the mitochondrial toxin NaN(3) were investigated in rat primary cortical neuron cultures. Cell viability (MTT colorimetric determination) and transmembrane mitochondrial potential (J-C1 fluorescence) were concentration-dependently reduced 24 h after NaN(3); neither nuclear fragmentation by DAPI, nor Annexin V positivity by flow cytometry were detected, ruling out the occurrence of apoptosis. The loss in cell viability (to 54 +/- 2%) observed 24 h after a 10-min treatment with 3 mM NaN(3) was prevented by the NMDA glutamate receptor antagonist MK801 (1 microM), by the antioxidants trolox (100 microM) and acetyl-L-carnitine (1 mM) and by the nitric oxide synthase inhibitor, L-NAME (100 microM), but not by the guanylylcyclase inhibitor ODQ, 10 microM.
View Article and Find Full Text PDFThe ethanolic extract from Hemidesmus indicus (Linn) (Apocynaceae) (Hie) was studied for its otoprotective effects in ex vivo rat organotypic model of gentamicin (GM) toxicity. In organ of Corti organotypic cultures (OC), GM can induce a fast dose-dependent apoptosis of hair cells (HC), both external and internal. We found that, after coadministration of GM and Hie to organotypic cultures, the extract was able to significantly counteract this toxic effect on HC, at the concentration of 25 and 50microg/ml.
View Article and Find Full Text PDFThis preliminary work was designed to study, using routine procedures for light and transmission electron microscopy, the presence of rodlet cells (RCs) in or near the sensory systems of 12 adult specimens (4.0 +/- 1.2 cm, LT +/- SD) of zebrafish, Danio rerio Hamilton, 1822.
View Article and Find Full Text PDFCisplatin is an anticancer drug currently used in the treatment of genital and head and neck tumors. Its use in these and other types of tumors is narrowed by onset of chemoresistance and severe undesired side effects, like as nephro- and ototoxicity, whose mechanisms of action are only partially understood. In the present study we investigated the effects of cisplatin (cis-dichlorodiaminoplatin, CDDP) on a cell line (OC-k3) developed from organs of Corti of transgenic mice.
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