Altered Intracellular Localization of SOD1 in Leukocytes from Patients with Sporadic Amyotrophic Lateral Sclerosis

Several lines of evidence support the hypothesis of a toxic role played by wild type SOD1 (WT-SOD1) in the pathogenesis of sporadic amyotrophic lateral sclerosis (SALS). In this study we investigated both distribution and expression profile of WT-SOD1 in leukocytes from 19 SALS patients and 17 healthy individuals. Immunofluorescence experiments by confocal microscopy showed that SOD1 accumulates in the nuclear compartment in a group of SALS subjects. These results were also confirmed by western blot carried out on soluble nuclear and cytoplasmic fractions, with increased nuclear SOD1 level (p<0.05). In addition, we observed the presence of cytoplasmic SOD1 aggregates in agreement with an increased amount of the protein recovered by the insoluble fraction. A further confirmation of the overall increased level of SOD1 has been obtained from single cells analysis using flow cytometry as cells from SALS patients showed an higher SOD1 protein content (p<0.05). These findings add further evidence to the hypothesis of an altered WT-SOD1 expression profile in peripheral blood mononuclear cells (PBMCs) from patients with ALS suggesting that WT-SOD1 species with different degrees of solubility could be involved in the pathogenesis of the disease.     

Modification of cell evagination and cell differentiation in quail oviduct hyperstimulated by progesterone

Quail oviduct development is controlled by sex steroid hormones. Estrogen (E) induce cell proliferation, formation of tubular glands by epithelial cell evagination and cell differentiation. Progesterone (P) strongly increases the secretory process in E-treated quails, but inhibits cell proliferation, cell evagination and differentiation of ciliated cells. The balance between E and P is critical for harmonious development of the oviduct. After 6 daily injections of two doses of estradiol benzoate (10 or 20 micrograms/d) and high doses of P (4 mg/d), tubular gland formation by epithelial cell evagination was inhibited, while epithelial cell proliferation occurred, as shown by the height of the villi and the increase in DNA. Secretory processes were strongly stimulated. Ovalbumin, a tubular gland cell marker and avidin, a mucous cell marker, were localized by immunofluorescence and immunogold labeling. Ovalbumin was localized only in the rudimentary tubular glands, whereas avidin was dispersed throughout the secretory cells. High doses of progesterone inhibited tubular gland cell proliferation, disturbed the distribution of avidin and inhibited differentiation of ciliated cells. Ovalbumin synthesis occurred only in epithelial cells which were evaginated despite the hyperstimulation. Ovalbumin gene expression appeared highly dependent upon the cell position.     

Cytochalasin D inhibits basal body migration and ciliary elongation in quail oviduct epithelium

Summary The effects of cytochalasin D (CD) were studied by scanning (SEM) and transmission (TEM) electron-microscopic examination at different stages of ciliary differentiation in epithelial cells of quail oviduct. Immature quails were prestimulated by estradiol benzoate injections to induce ciliogenesis in the undifferentiated oviduct. After 24 h of CD culture, SEM study revealed inhibition of ciliogenesis and dilation of the apex of non-ciliated cells. TEM study showed that 2 h of CD treatment produced dilation of lateral intercellular spaces, after 6 h of treatment, this resulted in intracellular macrovacuolation. Vacuoles were surrounded by aggregates of dense felt-like material. CD also induced the disappearance of microvilli, and rounding of the apical surface of undifferentiated cells and those blocked in ciliogenesis. Centriologenesis was not inhibited by CD; basal bodies assembled in generative complexes in the supranuclear region after 24 h of treatment. However, the migration of mature basal bodies towards the apical surface was impaired. Instead, they anchored onto the membrane of intracellular vacuoles; growth of cilia was induced in the vacuole lumen. Cilium elongation was disturbed, giving abnormally short cilia with a dilated tip; microtubules failed to organize correctly.     

Prime Ricerche sulla Fisionomia Enzimatica Caratteristica della Fotosintesi

Summary

The rate of oxidation of glucose-6-phosphate, ribose-5-phosphate, fructose-1,6- phosphate, iso-citrate and malate in extracts from green and etiolated pea leaves was determined, using the triphenyltetrazolium technique.

Glucose-6-phosphate, ribose-5-phosphate, and fructose-1,6-phosphate, in the presence of added TPN, where oxidized at a rate about twice higher in the extracts from green than in the extracts from etiolated leaves. Iso-citrate, in the presence of TPN, fructose-1,6-phosphate, in the presence of DPN, and malate, in the presence of either TPN or DPN, were oxidized at about the same rate in the two types of extracts.

These data seem to indicate a preferential synthesis of enzymes involved in the metabolic cycle of phosphorylated sugars during the transition of the leaf from the etiolated to the photosynthetising physiognomy. They seem also favourable to the view assigning to this metabolic system a primary importance in the anabolic pathway of photosynthesis.     

Inhibition of Retinoic Acid Metabolising Enzymes by 2-(4-aminophenylmethyl)-6-hydroxy-3,4-dihydronaphthalen-1(2H)-one and Related Compounds

In a search for inhibitors of all-trans retinoic acid (RA)-metabolising enzymes as potential agents for the treatment of skin conditions and cancer we have examined 2-(4-aminophenylmethyl)-6-hydroxy-3,4-dihydronaphthalen-1(2H)-one (5). Compound (5) is a moderate inhibitor of RA-metabolising enzymes in mammalian cadaverous tissue microsomes and homogenates as well as RA-induced enzymes in cultured human genital fibroblasts and HaCat cells. Overall (5) was more potent than or equipotent with ketoconazole, a standard inhibitor, in the cadaverous systems but less active towards the RA-induced cell culture systems. Examination of the data suggests that RA-induction generates metabolising enzymes not present in the cadaverous systems, which are more susceptible to inhibition by ketoconazole than (5).     

Flaxseed (Linum usitatissimum L.) extract as well as (+)-secoisolariciresinol diglucoside and its mammalian derivatives are potent inhibitors of α-amylase activity

Type 2 diabetes mellitus (T2DM) is one of the common global diseases. Flaxseed is by far the richest source of the dietary lignans (i.e., secoisolariciresinol diglucoside) which have been shown to delay the development of T2DM in animal models. Herein, we propose the first evidences for a mechanism of action involving the inhibition of the pancreatic α-amylase (EC 3.2.1.1) by flaxseed-derived lignans that could therefore constitute a promising nutraceutical for the prevention and the treatment of T2DM.