Resistance Exercise Program in Cognitively Normal Older Adults: CERT-Based Exercise Protocol of the AGUEDA Randomized Controlled Trial.

OBJECTIVES: To provide a comprehensive CERT (Consensus on Exercise Reporting Template)-based description of the resistance exercise program implemented in the AGUEDA (Active Gains in brain Using Exercise During Aging) study, a randomized controlled trial investigating the effects of a 24-week supervised resistance exercise program on executive function and related brain structure and function in cognitively normal older adults. DESIGN AND PARTICIPANTS: 90 cognitively normal older adults aged 65 to 80 were randomized (1:1) to a: 1) resistance exercise group; or a 2) wait-list control group. Participants in the exercise group (n = 46) performed 180 min/week of resistance exercise (3 supervised sessions per week, 60 min/session) for 24 weeks. INTERVENTION: The exercise program consisted of a combination of upper and lower limb exercises using elastic bands and the participant's own body weight as the main resistance. The load and intensity were based on the resistance of the elastic bands (7 resistances), number of repetitions (individualized), motor complexity of exercises (3 levels), sets and rest (3 sets/60 sec rest), execution time (40-60 sec) and velocity (as fast as possible). SETTINGS: The maximum prescribed-target intensity was 70-80% of the participants' maximum rate of perceived exertion (7-8 RPE). Heart rate, sleep quality and feeling scale were recorded during all exercise sessions. Those in the wait-list control group (n = 44) were asked to maintain their usual lifestyle. The feasibility of AGUEDA project was evaluated by retention, adherence, adverse events and cost estimation on the exercise program. RESULTS AND CONCLUSIONS: This study details the exercise program of the AGUEDA trial, including well-described multi-language manuals and videos, which can be used by public health professionals, or general public who wish to implement a feasible and low-cost resistance exercise program. The AGUEDA exercise program seems to be feasible by the high retention (95.6%) and attendance rate (85.7%), very low serious adverse event (1%) and low economic cost (144.23 € /participant/24 weeks). We predict that a 24-week resistance exercise program will have positive effects on brain health in cognitively normal older adults.

Structure, morphology, and bioactivity of biocompatible systems derived from functionalized acrylic polymers based on 5-amino-2-naphthalene sulfonic acid.

New therapeutic strategies for the treatment of neoplastic pathologies and, in particular, metastasis processes are based on the inhibitory effect of angiogenic processes. The present article deals with the design, preparation, and application of new "polymer drugs" with a clear inhibitory effect of the activation of fibroblast growth factors, which plays an important role in the proliferation of vascular cells and, consequently, in tumor angiogenesis. Two different copolymer systems based on 5-methacrylamide-2-naphthalenesulfonic acid (MANSA) and butylacrylate (BA) or vinylpyrrolidone (VP) were prepared by free radical copolymerization and exhaustively characterized. The molecular weight of the copolymers was moderate but both families presented very homogeneous macromolecular populations with a polydispersity index very close to unity, which indicates that MANSA presents a noticeable effect on the polymerization processes. The system poly(BA-co-MANSA) provides amphiphilic copolymers that give rise to the formation of oriented micelles with a core of the hydrophobic BA segments and a shell of MANSA components. The average size of these self-assembling nanoparticles is between 20 and 100 nm, depending on the composition of the copolymer system. However, poly(VP-co-MANSA) systems are more hydrophilic and give more homogeneous and water-soluble macromolecules. The bioactivity of both systems was studied by the analysis of proliferation of Balb/c 3T3 fibroblasts in the presence of acidic fibroblast growth factor (aFGF) as a function of the concentration of poly(BA-co-MANSA) or poly(VP-co-MANSA), and the results obtained demonstrated that the MANSA-containing polymers were not toxic for cells, but induced a clear inhibition of cell proliferation in the presence of aFGF. The effect was polymer-concentration dependent, but the activity was noticeably higher for poly(BA-co-MANSA) copolymers, owing to the self-assembled micellar morphology of the nanoparticles, which placed the sulfonic groups in the more adequate position to interact with the growth factor. These systems offer a good alternative for low toxicity treatments of angiogenic, processed based on inhibition of the activity of growth factors.

Electrochemically reduced graphene oxide on CoCr biomedical alloy: Characterization, macrophage biocompatibility and hemocompatibility in rats with graphene and graphene oxide.

Electrochemically reduced graphene oxide (ErGO) films on a biomedical grade CoCr alloy have been generated and characterized in order to study their possible application for use on joint prostheses. The electrodeposition process was performed by cyclic voltammetry. The characterization of the ErGO films on CoCr alloys by XPS revealed sp2 bonding and the presence of CO and CO residual groups in the graphene network. Biocompatibility studies were performed with mouse macrophages J774A.1 cell cultures measured by the ratio between lactate dehydrogenase and mitochondrial activities. An enhancement in the biocompatibility of the CoCr with the ErGO films was obtained, a result that became more evident as exposure time increased. Macrophages on the CoCr with the ErGO were well-distributed and conserved the characteristic cell shape. In addition, vimentin expression was unaltered in comparison with the control, results that indicated an improvement in the CoCr biocompatibility with the ErGO on the material surface. The in vivo response of graphene and graphene oxide was assessed by intraperitoneal injection in wistar rats. Red blood cells are one of the primary interaction sites so hemocompatibility tests were carried out. Rats inoculated with graphene and graphene oxide showed red blood cells of smaller size with a high content in hemoglobin.

Dobesilate inhibits the activation of signal transducer and activator of transcription 3, and the expression of cyclin D1 and bcl-XL in glioma cells.

OBJECTIVES: Because fibroblast growth factor (FGF) causes the intracellular accumulation of activated signal transducer and activator of transcription 3 (STAT3), we assessed whether dobesilate, a synthetic FGF inhibitor that has been reported to show antiproliferative and proapoptotic activities in glioma cell cultures, down-regulates the STAT3 signaling pathway in growing cultures of those cells. Because STAT3 signaling pathway plays pleiotropic roles in tumor proliferation, maintenance of STAT3 in its inactive state may prevent glioma growth and spreading. METHODS: Rat glioma C6 cells were treated with dobesilate and cultures were evaluated immunocytochemically for STAT3 activation and enhancement of the expression rate of cyclin D1 and bcl-XL. RESULTS: Dobesilate abrogates the accumulation of activated STAT3 in glioma cells. The decrease in the intracellular levels of activated STAT3 by the dobesilate treatment runs parallel with a significant attenuation of cyclin D1 and bcl-XL expression. CONCLUSION: Treatment with inhibitors of FGF down-regulates the STAT3 signaling pathway. These alterations could be correlated to the already observed inhibition of cell proliferation and promotion of apoptosis in glioma cell cultures by dobesilate. The reported results may open new avenues for developing new treatments against these tumors.

Solution structure of acidic fibroblast growth factor bound to 1,3, 6-naphthalenetrisulfonate: a minimal model for the anti-tumoral action of suramins and suradistas.

Recent data show that anti-angiogenesis may provide a promising route to treat cancer. Fibroblast growth factors (FGFs) are powerful angiogenic polypeptides, whose mitogenic activity requires the presence of heparin-like compounds. It has been shown that angiogenesis promoted by FGFs on inhibition by monoclonal antibodies and antisense targeting can also inhibit tumour growth. Derivatives of suramin, a polysulfonated binaphthyl urea and binaphthylsulfonated derivatives of distamycin, suradistas, constitute an important group of potential anti-cancer agents. These compounds compete with heparin in forming tight complexes with FGFs. This inhibits the recognition of these growth factors by their tyrosine kinase membrane receptors thereby suppressing their angiogenic activity. Here we show that 1,3,6-naphthalenetrisulfonate, a common chemical function of the suramins and suradistas with the highest anti-angiogenic activity inhibits the mitogenic activity of acidic fibroblast growth factor, and that this inhibition is relieved by increasing concentrations of heparin in the assay. We have also solved the three-dimensional structure in solution of the protein complexed to this compound. The structural data provide clues that may help in understanding the inhibitory effect of suramins and suradistas, and could contribute to the development of new anti-tumoral drugs.

Three-dimensional structure of acidic fibroblast growth factor in solution: effects of binding to a heparin functional analog.

Acidic and basic fibroblast growth factors (aFGF and bFGF; FGFs) are paradigms of a group of nine closely related proteins known as the fibroblast growth factor family. FGFs induce mitosis in most mesoderm- and neuroectoderm-derived cells, and appear to be involved in diseases caused by anomalous cell proliferation. In vitro assays show that binding to heparin-like glycosaminoglycans is required to elicit the mitogenic activity of these proteins. It has been shown that myo-inositol hexasulfate (MIHS) emulates heparin in the mitogenesis assays of aFGF, and a low-resolution three-dimensional structure in solution of this protein bound to MIHS has been reported. Here we describe the 1H-NMR three-dimensional structure in solution of the free aFGF. Comparison of this structure with that of the protein bound to MIHS, upgraded to a level of refinement equivalent to that of the free protein, shows that MIHS binding causes some slight conformational changes with an increase in the definition of the structure. In addition, amide exchange H/2H rates of the most protected protons, and exchange data of the intermediate and fast-exchanging ones show that the free protein is less stable (< or = 2 kcal/mol) and more flexible in terms of local unfolding equilibria, respectively, than the MIHS-bound one. Thus, MIHS binding to aFGF causes a decrease of its flexibility, which translates into an enhancement of the definition of its three-dimensional structure. The increase of aFGF rigidity affects regions that include those involved in recognizing the cell membrane receptor. Thus, our data suggest that enhancement of structural definition may play a key role in the modulation of the affinity of aFGF by its receptor, and, consequently, of its specific mitogenic activity.

Dobesilate is an angiogenesis inhibitor.

Aberrant angiogenesis is essential for the progression of solid tumors and hematological malignancies. Antiangiogenic therapy is one of the most promising approaches to treat such diseases. Dobesilate is an oral agent for treatment of vascular complications of diabetic retinopathy. We have examined the possibility that this compound could interfere with the process of angiogenesis in a mouse gelatine sponge assay using acidic fibroblast growth factor (aFGF) as an inducer of neovascularization. According to the results reported here, dobesilate remarkably reduced vessel ingrowth in aFGF-containing subcutaneous sponges in mice. These findings suggest that dobesilate could be an effective agent in the treatment of angiogenesis-dependent diseases involving FGFs.

High-level synthesis in Escherichia coli of shortened and full-length human acidic fibroblast growth factor and purification in a form stable in aqueous solutions.

A highly efficient expression for human acidic fibroblast growth factor (aFGF) has been assembled to direct the synthesis of both shortened and native full-length aFGF. The full-length aFGF-154 form of the protein had not been produced before in Escherichia coli by genetic engineering, and is obtained with its initiator methionine removed. The high production of the aFGF allows one to circumvent the use of reversed-phase chromatography (RPC) during the purification procedure. Here, it is shown that RPC, routinely used to obtain pure preparations of recombinant aFGF, modifies its chemical and physical properties in an unfavorable manner.

Systemic administration of acidic fibroblast growth factor ameliorates the ischemic injury of the retina in rats.

The central neuroprotective effects against ischemic injury of fibroblast growth factor (FGF), administered either directly into the central nervous system or systemically, is well documented. Here we show in a rat model of transient retinal ischemia that the neuroprotective effect of systemically administered acidic fibroblast growth factor (aFGF, FGF-1) extends to the retina. Histological findings show a lower decrease of retinal ganglion cells and inner nuclear layer cells (P < 0.0001) in animals receiving FGF-1. These results suggest that FGF may function as a natural protection agent during transient retinal ischemia and further document that an efficient neuroprotection of central nervous tissues can be obtained by systemic administration of this protein. Our data may, thus, contribute to the development of novel and safe therapeutic approach for the treatment of the ischemic injury of the retina.

Apoptosis of glioma cells induced by the fibroblast growth factor inhibitor 1,3,6-naphthalenetrisulfonate.

Fibroblast growth factors (FGFs) are powerful angiogenic polypeptides that are involved in the autocrine growth stimulation of gliomas. We report here that addition to glioma cell cultures of 1,3,6-naphthalenetrisulfonate (NTS), an inhibitor of the mitogenic activity of FGFs, significantly enhanced apoptosis, as assessed by terminal deoxynucleotidyl transferase (TdT) assay. The pro-apoptotic effect of NTS was time-dependent. These findings suggest that FGF may play a pivotal role in the survival of glioma cells, and support a clinical interest of NTS as a leading compound for the development of new antitumorals.

Abolished angiogenicity and tumorigenicity of rat glioma by 1-naphthalenemonosulfonate.

Suramins and suradistas, an important group of potential anti-cancer agents, inhibit fibroblast growth factor (FGF) mitogenic activity. It has been shown that naphthalenesulfonates, with a common chemical function to the family of suramins and suradistas, mimic their inhibitory activity, abolishing FGF-induced angiogenesis in vivo, and inducing apoptosis of C6 glioma cells in culture. In the present report, we show that intratumoral administration of 1-naphthalenemonosulfonate induces a considerable regression of gliomas in rats, significantly enhances apoptosis, and attenuates tumor angiogenesis. These findings may lead to new approaches for the treatment of glioblastoma, a most common primary malignant brain tumor of very poor prognosis, as well as of other angiogenesis-dependent malignancies.

Suppression of acidic fibroblast growth factor-dependent angiogenesis by the antigrowth activity of 1,3,6-naphthalenetrisulfonate.

Growth factor-induced angiogenesis was studied using subcutaneously implanted gelatin sponges loaded with 10 mg ml-1 of acidic fibroblast growth factor (aFGF) in 20 micrograms ml-1 PBS heparin. The administration of 1,3,6-naphthalenetrisulfonate (NTS) directly into the sponge (20 mg ml-1) or intraperitoneally (200 mg kg-1) blocks invasion of the sponge by vasculature. Since angiogenesis is essential for tumor progression, the findings of the present study that NTS is an efficient inhibitor of neovascularization warrant further investigation of the potential clinical utility of this angiostatic agent for treating tumor growth and metastasis.

Inhibition of intra-tumoral angiogenesis and glioma growth by the fibroblast growth factor inhibitor 1,3,6-naphthalenetrisulfonate.

1,3,6-naphthalenetrisulfonate (NTS) can inhibit the proliferation in vitro of cells of various origin including glioma. We have studied the effects of NTS on intra-tumoral angiogenesis and tumor growth in the rabbit cornea after implantation of C6 rat glioma cells. It was found that neovascularization and glioma growth were abolished by topical administration of NTS. This effect could be mediated by both induction of programmed cell death and inhibition of growth, in endothelium and in tumor cells, most likely as a consequence of the disruption of the autocrine and paracrine effects of FGF released from endothelial and tumor cells. The results suggest that NTS is a promising candidate to lead the development of new angiogenesis inhibitors for the treatment of cancer and other diseases whose progression is dependent upon the development of new blood vessels.

The contribution of the carotenoid to the visible circular dichroism of the light-harvesting antenna of Rhodospirillum rubrum.

The visible c.d. spectrum of wild-type Rhodospirillum rubrum shows positive bands [Dratz, Schultz & Sauer (1966) Brookhaven Symp. Biol. 19, 303-318] that are largely due to the B880 antenna pigments, bacteriochlorophyll a and carotenoids. The bacteriochlorophyll c.d. band was absent from the spectrum of R. rubrum G9, a mutant unable to synthesize coloured carotenoids, and could be partly restored by adding extracted carotenoids to freeze-dried membrane vesicles isolated from that mutant. Therefore it seems to arise from either bacteriochlorophyll-carotenoid interactions or bacteriochlorophyll-protein interactions that are induced by the carotenoid. The more complex carotenoid c.d. band had different shapes in native and reconstituted carotenoid-containing membranes. Such differences suggest that the optical activity of the carotenoid in the B880 antenna arises from both non-degenerate and degenerate interactions.

Thioredoxin-linked reductive inactivation of venom neurotoxins.

Thioredoxin, a 12-kDa protein with a catalytically active disulfide group, has recently been found to reduce intramolecular disulfide bonds in a variety of proteins. We now report that thioredoxin, reduced either enzymically with NADPH and NADP-thioredoxin reductase or chemically with dithiothreitol or lipoic acid, acts as a specific reductant of purified snake venom neurotoxins, a diverse group of disulfide proteins. Included were Bungarus multicinctus neurotoxins that act presynaptically (beta-bungarotoxin) or postsynaptically (alpha-bungarotoxin) as well as a postsynaptic neurotoxin from Laticauda semifasciata (erabutoxin b). We also observed a thioredoxin-specific reduction with other disulfide proteins of venom from Bungarus multicinctus, scorpion (Androctonus australis), and bee (Apis mellifera). Other cellular sulfhydryl agents, glutathione and glutaredoxin, were uniformly inactive. Thioredoxins from bacterial, plant, and animal sources were all active in neurotoxin reduction, but differed in effectiveness. Reduction of the neurotoxins by thioredoxin was accompanied by an increased susceptibility to tryptic proteolysis and a decrease of associated toxin activity: phospholipase A2 (beta-bungarotoxin, snake, and bee venoms) or acetylcholine receptor binding (alpha-bungarotoxin). These findings extend the function of thioredoxin to the reduction of a broad group of low-molecular-weight proteins, all containing intramolecular disulfide bonds. The loss of activity accompanying reduction raises the possibility that venoms may be detoxified by thioredoxin either as a defense mechanism or as a clinical antidote.

Destabilization, oligomerization and inhibition of the mitogenic activity of acidic fibroblast-growth factor by aurintricarboxylic acid.

The triphenylmethane derivative aurintricarboxylic acid has been used to inhibit angiogenesis, vascular smooth muscle cell proliferation and cell transformation, an effect that has been attributed to its relatively nonspecific inhibitory activity of protein-nucleic acid interactions. Here, we show that this compound binds to acidic fibroblast growth factor, a prototypic member of a family of protein mitogens activated by heparin, altering its physicochemical properties and decreasing its mitogenic activity. Counteraction of the effects of aurintricarboxylic acid by heparin shows that the two compounds have opposite and reversible effects on acidic fibroblast growth factor structure and biological activity. The studies reported here may contribute to a deeper understanding of the inhibition of fibroblast-growth-factor-dependent mitogenesis of relevance to future pharmacologic developments.

Thioredoxin: a multifunctional regulatory protein with a bright future in technology and medicine.

Thioredoxins are proteins, typically with a molecular mass of 12 kDa, that are widely, if not universally, distributed in the animal, plant, and bacterial kingdoms. Thioredoxins undergo reversible redox change through a disulfide group (S-S-->2 SH). Two cellular reductants--reduced ferredoxin and NADPH--supply the equivalents for reduction via different enzymes. The nature of the reductant serves as a basis for distinguishing and naming the two thioredoxin systems, which are discussed below in relation to their possible application in technology and medicine. Most of the discussion is referenced by general reviews. In the section dealing with animal cells, however, much of the material is quite recent. Thus, there, and elsewhere to a lesser extent, previously uncited studies are assigned specific references.

Dimeric carotenoid interaction in the light-harvesting antenna of purple phototrophic bacteria.

The carotenoid content of intracytoplasmic membrane vesicles isolated from purple phototrophic bacteria was reduced to a variable extent by mild extraction with light petroleum. Using preparations obtained from Rhodobacter capsulatus strains that contained the Light Harvesting System I (LHI) complex as the only major photosynthetic holochrome, it was shown that the visible circular dichroism of the carotenoids increased with the square of the membrane carotenoid content, as expected from being caused by dimeric exciton interaction. No chirality resulting from twists of the individual planar chromophore was detected. Therefore the contribution to carotenoid optical activity of non-degenerate interactions with bacteriochlorophyll or the apoprotein does not appear to be significant. The broadening of the absorption band of the bound pigment, caused by the splitting of the monomer transition, was demonstrated in membrane vesicles of both Rb, capsulatus and Rhodospirillum rubrum as a decrease of the fine structure of the band. Furthermore, the dimeric organization of the carotenoid pigments in the bacterial LHI complex accounted for the observed quantitative relationship between the fine structure of the band and the carotenoid content of the membrane.

Protection of rat myocardium by mitogenic and non-mitogenic fibroblast growth factor during post-ischemic reperfusion.

The effects of acidic fibroblast growth factor (FGF-1) and basic fibroblast growth factor (FGF-2) and a non mitogenic form of FGF1 on myocardial ischemia and reperfusion were assessed. Rats underwent 10 minutes of coronary artery occlusion followed by 24 hours of reperfusion. Creatinine kinase content of the affected myocardium showed that both fibroblast growth factors 1 and 2 effectively protected against ischemia reperfusion injury (p < 0.01), and that the vasoactive but nonmitogenic form of the FGF1 was equally protective (p < 0.01 versus control + vehicle). The results were confirmed by light and electron-microscopy histological studies. Histological evaluations after treatment with the non-mitogenic fibroblast growth factor 1 showed that it did not generate the severe hyperplasia and connective tissue disorganization observed with the native mitogenic proteins. The possibility of using a non-mitogenic form of fibroblast growth factor for cardio-protection circumvents many of the potentially undesirable effects that may derive from systemically introducing broad spectrum acting fibroblast growth factors in vivo. This myocardial protection observed 24 hours after the treatment with fibroblast growth factors, and the efficacy of the non-mitogenic form of the protein, also suggest that the protective effect of fibroblast growth factors may be due to the increased blood flow rather than to angiogenesis.

Folding stability of the kinetoplastid membrane protein-11 (KMP-11) from Leishmania infantum.

Kinetoplastid membrane protein-11 (KMP-11) is a major component of the cell surface of kinetoplastids, and acts as a potent B- and T-cell immunogen during Leishmania infection. Here we report that the Leishmania infantum KMP-11 secondary structure adopts mainly an alpha-helical conformation at pH 7.5 and that its urea- and thermally-induced unfolding constitute a fully reversible two-step process. This allows estimation of a half-denaturation temperature of approximately 65 degrees C, a delta GDH2O at 20 degrees C of approximately 14.63 kJ.mol-1, and an increment of the reaction heat of approximately 183.92 kJ.mol-1 and an entropy of approximately 543.4 J.mol-1.deg-1, respectively, for the native-denatured equilibrium of the KMP-11 in solution. We also report that the KPM-11 protein is induced to adopt a molten globule state at a pH range between pH 4 and pH 6. As a whole, the stability and the specific features of the denaturing effect induced by changes in pH are similar in KMP-11 to various other lipoproteins.