Late-Onset Running Biphasically Improves Redox Balance,Energy- and Methylglyoxal-Related Status,as well as SIRT1 Expression in Mouse Hippocampus

Despite the active research in this field, molecular mechanisms underlying exercise-induced beneficial effects on brain physiology and functions are still matter of debate, especially with regard to biological processes activated by regular exercise affecting the onset and progression of hippocampal aging in individuals unfamiliar with habitual physical activity. Since such responses seem to be mediated by changes in antioxidative, antiglycative and metabolic status, a possible exercise-induced coordinated response involving redox, methylglyoxal- and sirtuin-related molecular networks may be hypothesized. In this study, hippocampi of CD1 mice undergoing the transition from mature to middle age were analyzed for redox-related profile, oxidative and methylglyoxal-dependent damage patterns, energy metabolism, sirtuin1 and glyoxalase1 expression after a 2- or 4-mo treadmill running program. Our findings suggested that the 4-mo regular running lowered the chance of dicarbonyl and oxidative stress, activated mitochondrial catabolism and preserved sirtuin1-related neuroprotection. Surprisingly, the same cellular pathways were negatively affected by the first 2 months of exercise, thus showing an interesting biphasic response. In conclusion, the duration of exercise caused a profound shift in the response to regular running within the rodent hippocampus in a time-dependent fashion. This research revealed important details of the interaction between exercise and mammal hippocampus during the transition from mature to middle age, and this might help to develop non-pharmacological approaches aimed at retarding brain senescence, even in individuals unfamiliar with habitual exercise.     

Extracellular Matrix Molecular Remodeling in Human Liver Fibrosis Evolution

Chronic liver damage leads to pathological accumulation of ECM proteins (liver fibrosis). Comprehensive characterization of the human ECM molecular composition is essential for gaining insights into the mechanisms of liver disease. To date, studies of ECM remodeling in human liver diseases have been hampered by the unavailability of purified ECM. Here, we developed a decellularization method to purify ECM scaffolds from human liver tissues. Histological and electron microscopy analyses demonstrated that the ECM scaffolds, devoid of plasma and cellular components, preserved the three-dimensional ECM structure and zonal distribution of ECM components. This method has been then applied on 57 liver biopsies of HCV-infected patients at different stages of liver fibrosis according to METAVIR classification. Label-free nLC-MS/MS proteomics and computation biology were performed to analyze the ECM molecular composition in liver fibrosis progression, thus unveiling protein expression signatures specific for the HCV-related liver fibrotic stages. In particular, the ECM molecular composition of liver fibrosis was found to involve dynamic changes in matrix stiffness, flexibility and density related to the dysregulation of predominant collagen, elastic fibers and minor components with both structural and signaling properties. This study contributes to the understanding of the molecular bases underlying ECM remodeling in liver fibrosis and suggests new molecular targets for fibrolytic strategies.     

Essential oil variability in Thymbra capitata (L.) Cav. growing wild in Southern Apulia (Italy)

Essential oils of Thymbra capitata (Thymus capitatus) collected from Southern Apulia (Italy) were analysed using gas chromatography and gas chromatography–mass spectrometry techniques, to check for chemical variability. The study showed that among the 75 components of the oils the most recurrent ones were thymol and carvacrol, which always constituted more than 50% of the oils, as well as γ-terpinene, borneol and p-cymene. Cluster analysis led to the identification of three chemotypes: thymol, carvacrol and thymol/carvacrol; this was presumably a crossbreed between the other two chemotypes. Principal component analysis showed the direct correlation among myrcene, α-terpinene and γ-terpinene; anti-correlation between thymol and carvacrol, and the inverse correlation between linalool and myrcene. Moreover, lower thymol concentrations were accompanied by an increase in myrcene, α-terpinene and γ-terpinene.     

The Rapid Growth of Fibroids during Early Pregnancy

Several studies aimed to disentangle whether pregnancy influences the growth of uterine fibroids but results were inconsistent. In this study, we speculated that fibroid enlargement during pregnancy may not be linear and we hypothesized that this phenomenon may mainly occur during initial pregnancy. To test this hypothesis, we set up a prospective cohort study of women with fibroids undergoing IVF. Cases were women achieving a viable pregnancy. Controls were the subsequent women with fibroids but failing to become pregnant. Twenty-five cases and 25 controls were recruited. The total number of fibroids in the two groups was 46 and 41, respectively. The mean ± SD diameter of the fibroids was 17±10 and 20±11 mm, respectively (p = 0.18). A statistically significant enlargement emerged exclusively in pregnant women. The median (Interquartile Range) modification of the diameter of the lesions in cases and controls was +34% (+6%/+65%) and +2% (−6%/+12%), respectively (p<0.001). The median (Interquartile Range) modification of the volume of the lesions was +140% (+23%/+357%) and 0% (−18%/+37%), respectively (p<0.001). In pregnant women, we failed to document any significant correlation between the magnitude of the growth and ovarian responsiveness to hyper-stimulation, suggesting that steroids hormones are not the unique factors involved. In conclusion, fibroids undergo a rapid and remarkable growth during initial pregnancy. Reasons behind this phenomenon remain to be clarified. The early rise in steroids hormones during early pregnancy may not be sufficient to explain the process. Other pregnancy-related hormones and proteins may play also key roles.     

Modulation of Neurosteroid Synthesis/Accumulation by l-Ascorbic Acid in Rat Brain Tissue: Inhibition by Selected Serotonin Antagonists

Abstract: We have investigated the possibility that the synthesis/accumulation of neurosteroids, i.e., brain-produced steroids putatively endowed with modulatory actions in the CNS, is regulated by monoaminergic receptor-mediated mechanisms. In minces of rat brain cortex, l -ascorbic acid concentration-dependently (0.07–1.0 m M ) increases the levels of pregnenolone, allotetrahydrodeoxycorticosterone, and dehydroepiandrosterone. This effect of l -ascorbic acid is region-dependent: in hippocampus, progesterone and allopregnanolone are also increased, whereas dehydroepiandrosterone is unchanged, and in corpus striatum only progesterone is increased significantly. 5-Hydroxytryptamine (10 µ M ), 1-(3-chlorophenyl)piperazine (1.0 µ M ), and 5-methoxytryptamine (0.4 µ M ) mimic the effect of l -ascorbic acid, whereas a pretreatment with p -chlorophenylalanine (400 mg/kg i.p., 2 days) reduces the amplitude of the l -ascorbic acid effect on brain cortical neurosteroids. The effect of l -ascorbic acid is blocked by the nonselective serotonin antagonists methiothepin, clozapine, methysergide, and pizotifen, but not mesulergine, spiperone, MDL 72222, and dl -propranolol, nor by the catecholaminergic receptor antagonists prazosin and S (−)-sulpiride. l -Ascorbic acid is not additive with dibutyryl-cyclic AMP and, furthermore, the inhibition of adenylate cyclase by MDL 12330A, but not of phospholipase C by U-73122, markedly attenuates the l -ascorbic acid-induced increase of pregnenolone in rat brain cortical minces. Together these data suggest that l -ascorbic acid plays a role in the modulation of neurosteroidogenesis, presumably by favoring the activation of the purported serotonin type 6 receptor by endogenous serotonin.     

Proteome analysis of X-ray irradiated human erythroleukemia cells

In order to discover molecular biomarkers in radiation response we investigated the effects of X-radiation on radioresistant K562 cells by using a comparative proteomic analysis. In treated cells 29 up-regulated and 10 down-regulated proteins were detected by image analysis and identified by mass spectrometry. Elongation factor 1 alpha 1 and stress-70 protein showed a 6.2 and 5.4 fold increase respectively in treated cells. Additional proteins such us pi and omega classes glutathione transferases, ATP synthase D chain, were also found to be up-regulated, suggesting that the enzyme belonging to the cellular detoxification system against oxidative stress and energetic metabolism may have a key role in the cellular response to radiation injury. This data set may provide a useful tool to design a combined chemo- and radiotherapic strategy against leukemia disease.     

Different Allelic Distribution of a Single SNP Between Sexes in Humans

We searched for a difference in allele distribution between males and females of a single nucleotide polymorphism located in the human beta T-cell receptor, in 500 subjects (200 males and 300 females). Genotype analysis gave the following results: among the males, 114 (57%) were heterozygous for the T/C polymorphism, 52 (26%) were homozygous (T/T), and 34 (17%) were homozygous (C/C). Among the females, 142 (47.3%) were heterozygous, 73 (24.3%) were homozygous (T/T), and 85 (28.3%) were homozygous (C/C). The allele frequency was significantly different between sexes (chi2 = 8.799, P = 0.012).     

IFN-gamma arms human dendritic cells to perform multiple effector functions

Dendritic cells (DCs) are central players in immunity and are used in immune-adoptive vaccine protocols in humans. IFN-gamma, mandatory in Th-1 polarization and endowed with regulatory properties, is currently used to condition monocyte-derived DCs (MDDC) in cancer therapy and in clinical trials to treat chronic infectious diseases. We therefore performed a wide analysis of IFN-gamma signaling consequences on MDDC multiple effector functions. IFN-gamma itself induced IL-27p28 expression and survival but did not promote relevant CCR7-driven migration or activated Th-1 cell recruitment capacity in MDDC. Administered in association with classical maturation stimuli such as CD40 or TLR-4 stimulation, IFN-gamma up-regulated IL-27 and IL-12 production, CCR7-driven migration, and activated Th-1 cell recruitment, whereas it decreased IL-10 production and STAT3 phosphorylation. CD38 signaling, which orchestrates migration, survival, and Th-1 polarizing ability of mature MDDC, was involved in IFN-gamma-mediated effects. Thus, IFN-gamma is a modulator of multiple DC effector functions that can be helpful in MDDC-based vaccination protocols. These data also help understand the dual role exerted by this cytokine as both an inducer and a regulator of inflammation and immune response.     

The buried diversity of bovine seminal ribonuclease: shape and cytotoxicity of the swapped non-covalent form of the enzyme

Bovine seminal ribonuclease exists in the native state as an equilibrium mixture of a swapped and an unswapped dimer. The molecular envelope and the exposed surface of the two isomers are practically indistinguishable and their diversity is almost completely buried in the interior of the protein. Surprisingly, the cytotoxic and antitumor activity of the enzyme is a peculiar property of the swapped dimer. This buried diversity comes into light in the reducing environment of the cytosol, where the unswapped dimer dissociates into monomers, whereas the swapped one generates a metastable dimeric form (NCD-BS) with a quaternary assembly that allows the molecule to escape the protein inhibitor of ribonucleases. The stability of this quaternary shape was mainly attributed to the combined presence of Pro19 and Leu28. We have prepared and fully characterized by X-ray diffraction the double mutant P19A/L28Q (PALQ) of the seminal enzyme. While the swapped and unswapped forms of the mutant have structures very similar to that of the corresponding wild-type forms, the non-covalent form (NCD-PALQ) adopts an opened quaternary structure, different from that of NCD-BS. Moreover, model building clearly indicates that NCD-PALQ can be easily sequestered by the protein inhibitor. In agreement with these results, cytotoxic assays have revealed that PALQ has limited activity, whereas the single mutants P19A and L28Q display cytotoxic activity against malignant cells almost as large as the wild-type enzyme. The significant increase in the antitumor activity, brought about by the substitution of just two residues in going from the double mutant to the wild-type enzyme, suggests a new strategy to improve this important biological property by strengthening the interface that stabilizes the quaternary structure of NCD-BS.