TY  - JOUR
A1  - Simon, Christian M.
A1  - Rauskolb, Stefanie
A1  - Gunnersen, Jennifer M.
A1  - Holtmann, Bettina
A1  - Drepper, Carsten
A1  - Dombert, Benjamin
A1  - Braga, Massimiliano
A1  - Wiese, Stefan
A1  - Jablonka, Sibylle
A1  - Pühringer, Dirk
A1  - Zielasek, Jürgen
A1  - Hoeflich, Andreas
A1  - Silani, Vincenzo
A1  - Wolf, Eckhard
A1  - Kneitz, Susanne
A1  - Sommer, Claudia
A1  - Toyka, Klaus V.
A1  - Sendtner, Michael
T1  - Dysregulated IGFBP5 expression causes axon degeneration and motoneuron loss in diabetic neuropathy
JF  - Acta Neuropathologica
N2  - Diabetic neuropathy (DNP), afflicting sensory and motor nerve fibers, is a major complication in diabetes.The underlying cellular mechanisms of axon degeneration are poorly understood. IGFBP5, an inhibitory binding protein for insulin-like growth factor 1 (IGF1) is highly up-regulated in nerve biopsies of patients with DNP. We investigated the pathogenic relevance of this finding in transgenic mice overexpressing IGFBP5 in motor axons and sensory nerve fibers. These mice develop motor axonopathy and sensory deficits similar to those seen in DNP. Motor axon degeneration was also observed in mice in which the IGF1 receptor(IGF1R) was conditionally depleted in motoneurons, indicating that reduced activity of IGF1 on IGF1R in motoneurons is responsible for the observed effect. These data provide evidence that elevated expression of IGFBP5 in diabetic nerves reduces the availability of IGF1 for IGF1R on motor axons, thus leading to progressive neurodegeneration. Inhibition of IGFBP5 could thus offer novel treatment strategies for DNP.
KW  - Motor nerve biopsy
KW  - Diabetic polyneuropathy
KW  - Neuropathy
KW  - Neurotrophic factors
KW  - Axonal degeneration
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-154569
VL  - 130
SP  - 373
EP  - 387
ER  - 
TY  - JOUR
A1  - Haberstumpf, Sophia
A1  - Forster, André
A1  - Leinweber, Jonas
A1  - Rauskolb, Stefanie
A1  - Hewig, Johannes
A1  - Sendtner, Michael
A1  - Lauer, Martin
A1  - Polak, Thomas
A1  - Deckert, Jürgen
A1  - Herrmann, Martin J.
T1  - Measurement invariance testing of longitudinal neuropsychiatric test scores distinguishes pathological from normative cognitive decline and highlights its potential in early detection research
JF  - Journal of Neuropsychology
N2  - Objective
Alzheimer’s disease (AD) is a growing challenge worldwide, which is why the search for early-onset predictors must be focused as soon as possible. Longitudinal studies that investigate courses of neuropsychological and other variables screen for such predictors correlated to mild cognitive impairment (MCI). However, one often neglected issue in analyses of such studies is measurement invariance (MI), which is often assumed but not tested for. This study uses the absence of MI (non-MI) and latent factor scores instead of composite variables to assess properties of cognitive domains, compensation mechanisms, and their predictability to establish a method for a more comprehensive understanding of pathological cognitive decline.
Methods
An exploratory factor analysis (EFA) and a set of increasingly restricted confirmatory factor analyses (CFAs) were conducted to find latent factors, compared them with the composite approach, and to test for longitudinal (partial-)MI in a neuropsychiatric test battery, consisting of 14 test variables. A total of 330 elderly (mean age: 73.78 ± 1.52 years at baseline) were analyzed two times (3 years apart).
Results
EFA revealed a four-factor model representing declarative memory, attention, working memory, and visual–spatial processing. Based on CFA, an accurate model was estimated across both measurement timepoints. Partial non-MI was found for parameters such as loadings, test- and latent factor intercepts as well as latent factor variances. The latent factor approach was preferable to the composite approach.
Conclusion
The overall assessment of non-MI latent factors may pose a possible target for this field of research. Hence, the non-MI of variances indicated variables that are especially suited for the prediction of pathological cognitive decline, while non-MI of intercepts indicated general aging-related decline. As a result, the sole assessment of MI may help distinguish pathological from normative aging processes and additionally may reveal compensatory neuropsychological mechanisms.
KW  - Alzheimer’s disease
KW  - early-onset predictors
KW  - mild cognitive impairment
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-318932
VL  - 16
IS  - 2
SP  - 324
EP  - 352
ER  -