TY  - JOUR
A1  - Altmann, Stephan
A1  - Mut, Jürgen
A1  - Wolf, Natalia
A1  - Meißner-Weigl, Jutta
A1  - Rudert, Maximilian
A1  - Jakob, Franz
A1  - Gutmann, Marcus
A1  - Lühmann, Tessa
A1  - Seibel, Jürgen
A1  - Ebert, Regina
T1  - Metabolic glycoengineering in hMSC-TERT as a model for skeletal precursors by using modified azide/alkyne monosaccharides
JF  - International Journal of Molecular Sciences
N2  - Metabolic glycoengineering enables a directed modification of cell surfaces by introducing target molecules to surface proteins displaying new features. Biochemical pathways involving glycans differ in dependence on the cell type; therefore, this technique should be tailored for the best results. We characterized metabolic glycoengineering in telomerase-immortalized human mesenchymal stromal cells (hMSC-TERT) as a model for primary hMSC, to investigate its applicability in TERT-modified cell lines. The metabolic incorporation of N-azidoacetylmannosamine (Ac\(_4\)ManNAz) and N-alkyneacetylmannosamine (Ac\(_4\)ManNAl) into the glycocalyx as a first step in the glycoengineering process revealed no adverse effects on cell viability or gene expression, and the in vitro multipotency (osteogenic and adipogenic differentiation potential) was maintained under these adapted culture conditions. In the second step, glycoengineered cells were modified with fluorescent dyes using Cu-mediated click chemistry. In these analyses, the two mannose derivatives showed superior incorporation efficiencies compared to glucose and galactose isomers. In time-dependent experiments, the incorporation of Ac\(_4\)ManNAz was detectable for up to six days while Ac\(_4\)ManNAl-derived metabolites were absent after two days. Taken together, these findings demonstrate the successful metabolic glycoengineering of immortalized hMSC resulting in transient cell surface modifications, and thus present a useful model to address different scientific questions regarding glycosylation processes in skeletal precursors.
KW  - hMSC-TERT
KW  - metabolic glycoengineering
KW  - glycocalyx
KW  - modified monosaccharides
KW  - click chemistry
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259247
SN  - 1422-0067
VL  - 22
IS  - 6
ER  - 
TY  - JOUR
A1  - Mages, Michelle
A1  - Shojaa, Mahdieh
A1  - Kohl, Matthias
A1  - Stengel, Simon von
A1  - Becker, Clemens
A1  - Gosch, Markus
A1  - Jakob, Franz
A1  - Kerschan-Schindl, Katharina
A1  - Kladny, Bernd
A1  - Klöckner, Nicole
A1  - Lange, Uwe
A1  - Middeldorf, Stefan
A1  - Peters, Stefan
A1  - Schoene, Daniel
A1  - Sieber, Cornel C.
A1  - Tholen, Reina
A1  - Thomasius, Friederike E.
A1  - Uder, Michael
A1  - Kemmler, Wolfgang
T1  - Exercise effects on Bone Mineral Density in men
JF  - Nutrients
N2  - In contrast to postmenopausal women, evidence for a favorable effect of exercise on Bone Mineral Density (BMD) is still limited for men. This might be due to the paucity of studies, but also to the great variety of participants and study characteristics that may dilute study results. The aim of the present systematic review and meta-analysis was to evaluate the effect of exercise on BMD changes with rational eligibility criteria. A comprehensive search of six electronic databases up to 15 March 2021 was conducted. Briefly, controlled trials ≥6 months that determined changes in areal BMD in men >18 years old, with no apparent diseases or pharmacological therapy that relevantly affect bone metabolism, were included. BMD changes (standardized mean differences: SMD) of the lumbar spine (LS) and femoral neck (FN) were considered as outcomes. Twelve studies with 16 exercise and 12 control groups were identified. The pooled estimate of random-effect analysis was SMD = 0.38, 95%-CI: 0.14–0.61 and SMD = 0.25, 95%-CI: 0.00–0.49, for LS and FN, respectively. Heterogeneity between the trials was low–moderate. Funnel plots and rank and regression correlation tests indicate evidence for small study publication bias for LS but not FN-BMD. Subgroup analyses that focus on study length, type of exercise and methodologic quality revealed no significant difference between each of the three categories. In summary, we provided further evidence for a low but significant effect of exercise on BMD in men. However, we are currently unable to give even rough exercise recommendations for male cohorts.
KW  - Bone Mineral Density
KW  - exercise
KW  - men
KW  - overview
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-250247
SN  - 2072-6643
VL  - 13
IS  - 12
ER  - 
TY  - JOUR
A1  - Graser, Stephanie
A1  - Liedtke, Daniel
A1  - Jakob, Franz
T1  - TNAP as a new player in chronic inflammatory conditions and metabolism
JF  - International Journal of Molecular Sciences
N2  - This review summarizes important information on the ectoenzyme tissue-nonspecific alkaline phosphatase (TNAP) and gives a brief insight into the symptoms, diagnostics, and treatment of the rare disease Hypophosphatasia (HPP), which is resulting from mutations in the TNAP encoding ALPL gene. We emphasize the role of TNAP beyond its well-known contribution to mineralization processes. Therefore, above all, the impact of the enzyme on central molecular processes in the nervous system and on inflammation is presented here.
KW  - TNAP
KW  - Hypophosphatasia
KW  - HPP
KW  - mineralization
KW  - nervous system
KW  - inflammation
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-258888
SN  - 1422-0067
VL  - 22
IS  - 2
ER  -