Selective decline of 5-HT1A receptor binding sites in rat cortex, hippocampus and cholinergic basal forebrain nuclei during aging

The effect of aging on 5-HT1A receptor binding in several forebrain areas associated with the basal forebrain cholinergic system was investigated in rats of 3-, 24- and 30-months-old by receptor autoradiography and biochemical binding assay using [H-3]8-OH-DPAT as a ligand. Autoradiographic measurements demonstrated a marked region-specific decline of ligand binding in: (i) regions of the basal forebrain cholinergic cell groups, i.e. the medial septum, diagonal band nuclei and magnocellular nucleus basalis, (ii) the frontal and parietal neocortex and (iii) the dentate gyrus of the hippocampus. No change or- only a slight decrease of the 5-HT1A receptor density was found in other areas investigated: the CA1 and CA3 sectors of hippocampus, the cingular and perirhinal cerebral cortex and the lateral septum. The autoradiographic findings were substantiated by the biochemical binding assay, which revealed a comparable loss of 5-HT1A receptor in the hippocampus and neocortex at the age of 30 months. The results clearly show that with increasing age the decrement of 5-HT1A receptor binding in the rat forebrain is remarkably region-selective and particularly affects the cholinergic cell groups that innervate cortex and hippocampus. This phenomenon appears to be especially significant in relation to the neuronal substrates underlying the age-related alterations of mood and cognition. (C) 1997 Elsevier Science B.V

Whole body vibration improves attention and motor performance in mice depending on the duration of the whole-body vibration session

BACKGROUND: Whole body vibration (WBV) is a form of physical stimulation via mechanical vibrations transmitted to a subject. It is assumed that WBV induces sensory stimulation in cortical brain regions through the activation of skin and muscle receptors responding to the vibration. The effects of WBV on muscle strength are well described. However, little is known about the impact of WBV on the brain. Recently, it was shown in humans that WBV improves attention in an acute WBV protocol. Preclinical research is needed to unravel the underlying brain mechanism. As a first step, we examined whether chronic WBV improves attention in mice.MATERIAL AND METHODS: A custom made vibrating platform for mice with low intensity vibrations was used. Male CD1 mice (3 months of age) received five weeks WBV (30 Hz; 1.9 G), five days a week with sessions of five (n=12) or 30 (n=10) minutes. Control mice (pseudo-WBV; n=12 and 10 for the five and 30 minute sessions, respectively) were treated in a similar way, but did not receive the actual vibration. Object recognition tasks were used as an attention test (novel and spatial object recognition - the primary outcome measure). A Balance beam was used for motor performance, serving as a secondary outcome measure.RESULTS: WBV sessions of five (but not WBV sessions of 30 minutes) improved balance beam performance (mice gained 28% in time needed to cross the beam) and novel object recognition (mice paid significantly more attention to the novel object) as compared to pseudo WBV, but no change was found for spatial object performance (mice did not notice the relocation). Although 30 minutes WBV sessions were not beneficial, it did not impair either attention or motor performance.CONCLUSION: These results show that brief sessions of WBV improve, next to motor performance, attention for object recognition, but not spatial cues of the objects. The selective improvement of attention in mice opens the avenue to unravel the underlying brain mechanisms.</p

The TNFR1 antagonist Atrosimab reduces neuronal loss, glial activation and memory deficits in an acute mouse model of neurodegeneration

Abstract Tumor necrosis factor alpha (TNF-α) and its key role in modulating immune responses has been widely recognized as a therapeutic target for inflammatory and neurodegenerative diseases. Even though inhibition of TNF-α is beneficial for the treatment of certain inflammatory diseases, total neutralization of TNF-α largely failed in the treatment of neurodegenerative diseases. TNF-α exerts distinct functions depending on interaction with its two TNF receptors, whereby TNF receptor 1 (TNFR1) is associated with neuroinflammation and apoptosis and TNF receptor 2 (TNFR2) with neuroprotection and immune regulation. Here, we investigated the effect of administering the TNFR1-specific antagonist Atrosimab, as strategy to block TNFR1 signaling while maintaining TNFR2 signaling unaltered, in an acute mouse model for neurodegeneration. In this model, a NMDA-induced lesion that mimics various hallmarks of neurodegenerative diseases, such as memory loss and cell death, was created in the nucleus basalis magnocellularis and Atrosimab or control protein was administered centrally. We showed that Atrosimab attenuated cognitive impairments and reduced neuroinflammation and neuronal cell death. Our results demonstrate that Atrosimab is effective in ameliorating disease symptoms in an acute neurodegenerative mouse model. Altogether, our study indicates that Atrosimab may be a promising candidate for the development of a therapeutic strategy for the treatment of neurodegenerative diseases

Neoadjuvant immunotherapy with nivolumab and ipilimumab induces major pathological responses in patients with head and neck squamous cell carcinoma

Surgery for locoregionally advanced head and neck squamous cell carcinoma (HNSCC) results in 30‒50% five-year overall survival. In IMCISION (NCT03003637), a non-randomized phase Ib/IIa trial, 32 HNSCC patients are treated with 2 doses (in weeks 1 and 3) of immune checkpoint blockade (ICB) using nivolumab (NIVO MONO, n = 6, phase Ib arm A) or nivolumab plus a single dose of ipilimumab (COMBO, n = 26, 6 in phase Ib arm B, and 20 in phase IIa) prior to surgery. Primary endpoints are feasibility to resect no later than week 6 (phase Ib) and primary tumor pathological response (phase IIa). Surgery is not delayed or suspended for any patient in phase Ib, meeting the primary endpoint. Grade 3‒4 immune-related adverse events are seen in 2 of 6 (33%) NIVO MONO and 10 of 26 (38%) total COMBO patients. Pathological response, defined as the %-change in primary tumor viable tumor cell percentage from baseline biopsy to on-treatment resection, is evaluable in 17/20 phase IIa patients and 29/32 total trial patients (6/6 NIVO MONO, 23/26 COMBO). We observe a major pathological response (MPR, 90‒100% response) in 35% of patients after COMBO ICB, both in phase IIa (6/17) and in the whole trial (8/23), meeting the phase IIa primary endpoint threshold of 10%. NIVO MONO’s MPR rate is 17% (1/6). None of the MPR patients develop recurrent HSNCC during 24.0 months median postsurgical follow-up. FDG-PET-based total lesion glycolysis identifies MPR patients prior to surgery. A baseline AID/APOBEC-associated mutational profile and an on-treatment decrease in hypoxia RNA signature are observed in MPR patients. Our data indicate that neoadjuvant COMBO ICB is feasible and encouragingly efficacious in HNSCC

Kommunikation i komplexa sociala miljöer - en modell för kommunikationsmanagement

IT-projekt där konsult och kund ska samarbeta är en komplex social miljö. I analysfasen är informationen som kommuniceras omfattande och rik. Brister i förståelse förekommer ofta. Denna rapport presenterade en ny modell som kompletterar de traditionella kommunikationsmodellerna och dess olika effekter. Modellen kan ses som en integration av två grundläggande teorier: dels kommunikationsteorier i allmänhet och Dafts richness-teori i synnerhet, dels Langefors infologiska teori. Modellen validerades genom intervjuer med konsulter och kunder. Studien visade att kommunikationens effekter kan beskrivas i termer av olika förbättringar så som produktkvalitet, processkvalitet, innovativa idéer, ekonomisk vinst och positiv arbetsmiljö. Dessa förbättringar kan ses som en konsekvens av kommunikationens omfång, form och innehåll, deltagare samt kontext. För att dessa ska fungera måste kommunikationsmanagement säkra förutsättningar för funktionell, strukturell, infologisk och socialkulturell harmoni

Input from the medial septum regulates adult hippocampal neurogenesis

Neural progenitors in the subgranular zone of the hippocampal formation form a continuously proliferating cell population, generating new granule neurons throughout adult life. Between 10 days and 1 month after their formation, many of the newly generated cells die. The present study investigated whether a partial lesion of one of the main nuclei projecting to the hippocampus, the medial septum (MS), affects survival and differentiation of cells during this critical period. Rats were injected with BrdU and 5 days later excitotoxic lesion of the MS was applied by infusion of either 30 or 60 nmol of N-methyl-D-aspartate (NMDA). One week after the lesion, quantification of immunopositive cells revealed that the number of GABAergic cells was significantly reduced in both lesioned groups, whereas a decline in cholinergic cell number was observed only after injection of 60 nmol of NMDA. The partial septohippocampal denervation significantly reduced hippocampal neurogenesis. Survival of newly generated neurons was decreased by approximately 40%. The MS lesion did not affect proliferation of hippocampal progenitors. The present study points out the importance of a functional septohippocampal pathway for the regulation of hippocampal neurogenesis and highlights the potential role of GABA as a mediator in this phenomenon.

Galantamine-induced behavioral recovery after sublethal excitotoxic lesions to the rat medial septum

Clinical trials show beneficial effects of acetylcholinesterase (AChE) inhibitors, including galantamine, on cognitive functions in patients with mild to moderate Alzheimer’s disease. Galantamine shows a dual action profile by also acting as an allosteric modulator of nicotinic acetylcholine receptors. Nevertheless, its in vivo mechanism of action is only partly understood. Here, we first established a novel lesion model provoking significant functional impairment of the septo-hippocampal projection system without triggering massive neuronal death in the rat medial septum. Next, we studied whether galantamine, administered in doses of 1 and 3 mg/kg post-lesion, promotes functional recovery of spatial navigation behaviors, and affects the output of septal cholinergic projections. Infusion of N-methyl-D-aspartate (NMDA; 30 nmol/1µl) in the medial septum resulted in spatial learning deficits associated with significant shrinkage of cholinergic neurons and reduced AChE activity in the hippocampus at 7 days post-lesion. Galantamine treatment alone significantly increased the hippocampal acetylcholine concentration and attenuated the NMDA-induced spatial learning impairment. Galantamine post-treatment also affected NMDA-induced changes in AChE and choline-acetyltransferase activities. In conclusion, our data show that galantamine attenuates experimentally-induced cognitive impairments underscored by mild neuronal damage.

Aging is accompanied by a subfield-specific reduction of serotonergic fibers in the tree shrew hippocampal formation

The hippocampal formation is a crucial structure for learning and memory, and serotonin together with other neurotransmitters is essential in these processes. Although the effects of aging on various neurotransmitter systems in the hippocampus have been extensively investigated, it is not entirely clear whether or how the hippocampal serotonergic innervation changes during aging. Rat studies, which have mostly focused on aging-related changes in the dentate gyrus, have implied a loss of hippocampal serotonergic fibers. We used the tree shrew (Tupaia belangeri), an intermediate between insectivores and primates, as a model of aging. We applied immunocytochernistry with an antibody against serotonin to assess serotonergic fiber densities in the various hippocampal subfields of adult (0.9-1.3 years) and old (5-7 years) tree shrews. Our results have revealed a reduction of serotonergic fiber densities in the stratum radiatum of CA1 and CA3, and in the stratum oriens of CA3. A partial depletion of serotonin in the hippocampal formation, as can be expected from our current observations, will probably have an impact on the functioning of hippocampal principal neurons. Our findings also indicate that the rat and the tree shrew hippocampal serotonergic innervation show some variations that seem to be differentially affected during aging. (c) 2005 Elsevier B.V. All rights reserved

Differential testosterone secretory capacity of the testes of aggressive and nonaggressive house mice during ontogeny

In this study, testosterone secretory capacity of testicular Leydig cells during ontogeny was determined in males of an aggressive and a nonaggressive genetic selection line of wild house mice. Neonates, 23-day-old prepubertals, and adult male mice were studied. A morphometric method was used to quantify 3-beta-hydroxy steroid dehydrogenase (3-beta-HSD)-stained Leydig cells in testicular sections to determine testosterone secretory capacity. We consider this parameter to reflect circulating testosterone in the plasma. The results of this study show that the testosterone secretory capacity of Leydig cells in the testis changes differentially during development in males of the aggressive and nonaggressive selection lines. This capacity is highest in the aggressive selection line males at adulthood and at the prepubertal age of 23 days. Surprisingly, at birth, the highest T-secretory capacity was observed in the males of the nonaggressive selection line. The significance of an interaction between genetic factors and differences in perinatal testosterone for the individual variation in adult aggressive behavior is discussed.</p