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Frailty is a geriatric syndrome associated with both locomotor and cognitive decline, implicated in both poor quality of life and negative health outcomes. One central question surrounding frailty is whether phenotypic frailty is associated with the cognitive impairment during aging. Using spontaneous behavioral tests and by studying the dynamic change during aging, we demonstrated that the two form of vulnerability, locomotor and recognition memory decline, develop in parallel and therefore, integration of the motoric and cognitive evaluations are imperative. We developed an integrated frailty index based on both phenotypic and recognition memory performances. Hericium erinaceus (H. erinaceus) is a medicinal mushroom that improves recognition memory in mice. By using HPLC-UV-ESI/MS analyses we obtained standardized amounts of erinacine A and hericenones C and D in H. erinaceus extracts, that were tested in our animal model of physiological aging. Two-month oral supplementation with H. erinaceus reversed the age-decline of recognition memory. Proliferating cell nuclear antigen (PCNA) and doublecortin (DCX) immunohistochemistry in the hippocampus and cerebellum in treated mice supported a positive effect of an H. erinaceus on neurogenesis in frail mice.

The aim of this paper is to review the data in the literature concerning ribonucleoprotein components during apoptosis, where a major rearrangement of RNPs takes place. In parallel with chromatin changes, the nucleoplasmic constituents (perichromatin fibrils; perichromatin granules; interchromatin granules and nuclear bodies) as well as the nucleoli aggregate into heterogeneous clusters called HERDS, in the interchromatin space. Later, these RNP-containing structures are extruded from the nucleus and leave the cell within cytoplasmic blebs. We propose also a role for HERDS as markers of irreversible transcriptional arrest. © 2004 Elsevier SAS. All rights reserved.Keywords: Electron microscopy; HERDS; Immunocytochemistry; Nuclear ribonucleoproteins; Transcription The cell nucleus during apoptosis: an introductionThe basic functions of the nucleus such as replication, transcription, DNA repair and their timing, as well as the correct sorting of information need an architectural support; this support, however, needs not to be a stable structural one only, but preferably derived from the dynamic interaction of many different components to be -at the same time-flexible and stable enough for these processes to proceed (Marshall, 2002;Stein et al., 2003).The nucleus is compartmentalized, both structurally and functionally and, in fact, may be considered as composed of at least two largely interacting parts: chromatin and the ribonucleoprotein (RNP)-containing structures. Already during the sixties of the last century, Bernhard and co-workers (Bernhard, 1969;Monneron and Bernhard, 1969; Bernhard, 1971,1973) showed that, thanks to a rather simple ultrastructural technique based on treatment with EDTA, condensed chromatin may be quite efficiently bleached whereas the interchromatin space becomes more contrasted. Under these conditions, it was possible -for the very first time-to detect and describe in detail some RNP-based structures. Those pioneering papers have then been followed by a plethora of articles aimed at elucidating the organization, chemical composition and functional significance of nuclear RNPs (for a recent review, see Fakan, 2004, and Table 1). One specific region (or domain), perichromatin compartment, is of particular interest since it is the place where most of the functions related to transcription, splicing and gene silencing are located (Cmarko et al., 2003).It is now widely accepted that, in eukaryotic cells, nuclear RNPs are part of the transcription and splicing machinery, and are always organized as morphologically recognizable structures (as schematically reported in Fig. 1a); at the electron microscope, these structures have been described as perichromatin fibrils (PF), perichromatin granules (PG), and interchromatin granules (IG) (Fakan, 1994;Spector, 1996), and nucleolus (Raška et al., 2004, in this issue). These structures are characterized by the presence of some marker proteins, such as hnRNP core proteins in PF (Martin and Okamura, 1981;Fakan et al., 1984), SC-35, Sm and PANA ...

We evaluated the relationship among proliferation, death and migration of granule cells in lobules VI-VIII of vermis, in comparison with lobule III, during cerebellar development. To this aim, a single injection of cisplatin, i.e., a cytostatic agent that is known to induce death of proliferating granule cells, was given to 10-day-old rats. Histochemical markers of proliferating (PCNA immunoreaction) and apoptotic (TUNEL staining) cells were used; the variations of the external granular layer (EGL) thickness were evaluated in parallel. After PCNA and TUNEL reactions, evident changes of the whole EGL were found on PD11 (1 day after treatment), when a reduction of the thickness of this layer was found in treated rats, mainly in consequence of the high number of apoptotic cells in all the cerebellar lobules. On PD17 (7 days after treatment), a thick layer of proliferating cells was observed in lobules VI-VIII of treated rats, while the peculiar pattern of the normal development showed a thin EGL. At the same time, in treated rats, the number of apoptotic cells in EGL was low. In all developmental stages of treated rats, after GFAP immunoreaction, glial fibers appeared twisted, thickened, and with an irregular course; intensely labeled end-feet were present. The damage of radial glia suggests an alteration of migratory processes of granule cells, which is also evidenced by the decreased thickness of the premigratory zone of the EGL. Injured radial glia fibers were restricted to lobules VI-VIII and they persisted at PD30, leading to the presence of ectopic granule cells in the molecular layer, as we previously described.

SUMMARY During spontaneous apoptosis of thymocytes there is extrusion of ribonucleoproteins (RNPs) from the cell. The aim of this investigation was to elucidate whether the RNP aggregates in apoptotic cells and bodies still contain RNA in an appreciable amount. We demonstrated by specific cytochemical techniques that the aggregates of nuclear RNPs extruded in the cytoplasm of spontaneously apoptotic thymocytes contain RNA in a sufficient amount to be detected cytochemically. These heterogeneous ectopic RNP-derived structures (HERDS) are formed by perichromatin fibrils, interchromatin granules, perichromatin granules, and nucleolar material. The RNA detected inside these clusters should therefore correspond to both mRNA and snRNA as well as to rRNA. We never observed DNA-contaning aggregates in the cytoplasm of apoptotic thymocytes. The presence of RNA in the HERDS that may be released from apoptotic cells suggests that the decrease in the amount of total RNA during apoptosis may be mostly linked to cellular extrusion rather than to degradation of RNA by RNase activities. Another interesting aspect of these results lies in the hypothesis of apoptosis as a possible cause for the presence of autoantibodies in the serum of patients with systemic autoimmune diseases.