The aim of the present study was to assess age-dependent changes of proteins in the vastus lateralis muscle of physically active elderly and young subjects by a combination of two-dimensional difference gel electrophoresis, SDS-PAGE and ESI-MS/MS. The differences observed in the elderly group included down-regulation of regulatory myosin light chains, particularly the phosphorylated isoforms, a higher proportion of myosin heavy chain isoforms 1 and 2A, and enhanced oxidative and reduced glycolytic capacity.

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Nitric oxide is becoming an increasingly important signalling molecule implicated in a growing number of physiological and pathophysiological processes. Moreover, with the recent advances in nitric oxide biochemistry, many well known drugs have been shown to act totally or partially by modulating NO metabolism with varying therapeutic results. The classic organic nitrates have been shown to exhibit beneficial therapeutic but suffer from some well known pitfalls (tolerability induction, abrupt cephalea and hypotension). Similarly, sydnonimines, another well known class of NO donor drugs, have a characteristically low therapeutic index (i.e., cyanide toxicity). At present, pharmacological researchers are designing and synthesising various chemical compounds capable of modulating NO metabolism for therapeutic purposes that also possess an optimal therapeutic index. Specifically, various new classes of NO donors are under intense pharmacological investigation (such as S-nitrosothiols, diazeniumdiolates, furoxans, zeolites and so on), each characterised by a particular pharmacokinetic and pharmacodynamic profile. To known the pharmacological development of these new NO donor drugs could help to ameliorate the use of these molecules in various therapeutic protocols. In fact, the pharmacologically modulated nitric oxide release showed to have an important therapeutic impact in the treatment of diseases such as arteriopathies, various acute and chronic inflammatory conditions, and several degenerative diseases. At present, the most important obstacle in the field of new NO donor drugs seems to be carefully targeting NO release to a particular tissue at an optimal concentration, so as to achieve a beneficial action and to limit possible toxic effects.

Although the only effective drug against primary hepatocarcinoma, the multikinase inhibitor Sorafenib (SFB) usually fails to eradicate liver cancer. Since SFB targets mitochondria, cell metabolic reprogramming may underlie intrinsic tumor resistance. To characterize cancer cell metabolic response to SFB, we measured oxygen consumption, generation of reactive oxygen species (ROS) and ATP content in rat LCSC (Liver Cancer Stem Cells) -2 cells exposed to the drug. Genome wide analysis of gene expression was performed by Affymetrix technology. SFB cytotoxicity was evaluated by multiple assays in the presence or absence of metabolic inhibitors, or in cells genetically depleted of mitochondria. We found that low concentrations (2.5–5 μM) of SFB had a relatively modest effect on LCSC-2 or 293 T cell growth, but damaged mitochondria and increased intracellular ROS. Gene expression profiling of SFB-treated cells was consistent with a shift toward aerobic glycolysis and, accordingly, SFB cytotoxicity was dramatically increased by glucose withdrawal or the glycolytic inhibitor 2-DG. Under metabolic stress, activation of the AMP dependent Protein Kinase (AMPK), but not ROS blockade, protected cells from death. We conclude that mitochondrial damage and ROS drive cell killing by SFB, while glycolytic cell reprogramming may represent a resistance strategy potentially targetable by combination therapies.

Aim: Genetic investigations explain only a small percentage of cases of nonobstructive azoospermia (NOA), a condition that affects up to 2% of infertile couples. This study aimed to identify further genomic variants that are associated with primary spermatogenic failure within the testis. Methods: One family with 2 infertile siblings affected by NOA was genotyped by whole-exome sequencing. DNA variants were filtered based on quality score, allele frequency, and functional roles of genes in spermatogenesis. Results: Both NOA males were compound heterozygotes for a nonsense mutation and a single nucleotide deletion leading to premature stop codons in the TEX15 gene (c.2419A>T, p.Lys807*, and c.3040delT, p.Ser1014Leufs*5, respectively). The single mutations were identified only on one allele in 6 family members, including 3 fertile males who conceived naturally. Conclusion: This is the second reported case of a TEX15 deleterious mutation cosegregating with NOA in a family in which the infertile phenotype is reminiscent of the one observed in the TEX15-knockout mouse, confirming that TEX15 plays a critical role in normal spermatogenesis and its defects may be responsible for a number of NOA cases.

Most cancer cells exhibit elevated levels of glycolysis and this metabolic pathway seems to be related to a greater glucose uptake. This phenomenon, known as the Warburg effect, is considered one of the most fundamental metabolic alterations during malignant transformation. Originally, Warburg hypothesised that the aerobic glycolysis of cancer cells could be just an aspect of a more complex metabolic adaptation. However, this intriguing discovery was partially misinterpreted and disregarded over time. In recent years, the peculiarities of cancer cell metabolism have been re-evaluated in light of new metabolic data that seem to confirm and to widen the original concept of the Warburg effect. In fact, biochemical, molecular, and, above all, proteomic studies on the multifaceted roles of glycolytic enzymes in cancer cells in general, and in cancer stem cells in particular, seem to suggest more complex functional adaptations. These adaptations result in significantly altered protein expression patterns, and they have fundamental implications for diagnosis, prognosis and therapy. Revisiting the Warburg effect in cancer cells with a proteomic approach could deepen our knowledge of cancer cell metabolism and of cancer cell biology in general. Moreover, by identifying useful diagnostic, prognostic and therapeutic targets, it could significantly impact clinical practice.

The characterization of the molecular phenotype of these cancer stem-like cells, associated with an accurate definition of their typical derangement in cell differentiation, can represent a fundamental advance in terms of diagnosis and therapy of cancer. Preliminary results seem to be promising but further studies are required to define the therapeutic index of this new anticancer treatment. Moreover, understanding the pathogenetic mechanisms of CSCs can expand the therapeutic applications of normal adult stem cells by reducing the risk of uncontrolled tumorigenic stem cell differentiation.

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