bioRxiv Science⌕ Search

Biology subjects

Stange, R.

Publications and source records attributed to Stange, R..

4 recordsLinked to original sources

BEHAVIOURAL VOLUNTARY AND SOCIAL BIOASSAYS ENABLING IDENTIFICATION OF COMPLEX AND SEX DEPENDENT PAIN- (-RELATED) PHENOTYPES IN RATS WITH BONE CANCER

Cancer-induced bone pain (CIBP) is a common and devastating symptom with limited treatment options in patients, significantly affecting their quality of life. To uncover the mechanisms underlying CIBP, using rodent models is the most common approach; however, the translation of results to the clinic may be hindered because the assessment of pain-related behavior is often based exclusively on reflexive-based methods, which are only partially indicative relevant pain in patients. In order to improve the accuracy and strength of the preclinical experimental model of CIBP in rodents, we used a battery of multimodal behavioral tests that were also aimed at identifying rodent-specific behavioral components by using a homecage monitoring assay (HCM). Rats of all sexes received an injection with either heat-deactivated (sham-group) or potent mammary gland carcinoma Walker 256 cells into the tibia. By integrating multimodal datasets, we assessed pain-related behavioral trajectories of CIBP-phenotype, including evoked and non-evoked based assays and HCM. Using principal component analysis (PCA), we discovered sex-specific differences in establishing the CIBP-phenotype, which occurred earlier (and different) in males. In addition, HCM phenotyping revealed the occurrence of sensory-affective states manifested by mechanical hypersensitivity in sham when housed with a tumor-bearing cagemate (CIBP) of the same sex. This multimodal battery allows an in-depth characterization of the CIBP-phenotype under social aspects in rats. The detailed, sex-specific, and rat-specific social phenotyping of CIBP enabled by PCA provides the basis for mechanism-driven studies to ensure robustness and generalisability of results and provide information for targeted drug development in the future.

cancer biology↗

Human Sex Matters: Y-linked lysine demethylase 5D drives accelerated male osteogenic differentiation

Female sex is increasingly associated to a loss of bone mass during aging and an increased risk for fractures developing nonunion. Hormonal factors and cell-intrinsic mechanisms are suggested to drive these sexual dimorphisms, although underlying molecular mechanisms are still a matter of debate. Here, we observed a decreased capacity of calvarial bone recovery in female rats and a profound sexually dimorphic osteogenic differentiation human adult neural crest-derived stem cells (NCSCs). Next to an elevated expression of pro-osteogenic regulators, global trancriptomics revealed Lysine Demethylase 5D (KDM5D) to be highly upregulated in differentiating male NCSCs. Loss of function by siRNA or pharmacological inhibition of KDM5D significantly reduced the osteogenic differentiation capacity of male NCSCs. In summary, we demonstrate craniofacial osteogenic differentiation to be sexually dimorphic with the expression of KDM5D as a prerequisite for accelerated male osteogenic differentiation, emphasizing the analysis of sex-specific differences as a crucial parameter for treating bone defects.

cell biology↗

MiR-146a controls age related bone loss

Bone loss is one of the consequences of aging, leading to diseases such as osteoporosis and increased susceptibility to fragility fractures and therefore considerable morbidity and mortality in humans. Here we identify microRNA 146a as an essential epigenetic switch controlling bone loss with age. Mice deficient in miR-146a show regular development of their skeleton. However, while WT mice start to lose bone with age, animals deficient in miR-146a continue to accrue bone throughout their life span. Increased bone mass is due to increased generation and activity of osteoblasts in miR-146a deficient mice as a result of sustained activation of bone anabolic Wnt signaling during aging. Deregulation of the miR-146a target genes Wnt1 and Wnt5a parallel bone accrual and osteoblast generation, which is accompanied by reduced development of bone marrow adiposity. Furthermore, miR-146a deficient mice are protected from ovariectomy induced bone loss. In humans, levels of miR-146a are increased in patients suffering fragility fractures in comparison to those who do not. These data identify miR-146a as a crucial epigenetic temporal regulator which essentially controls bone homeostasis during aging by regulating bone anabolic Wnt signaling. Therefore, miR-146a might be a powerful therapeutic target to prevent age related bone dysfunction such as the development of bone marrow adiposity and osteoporosis.

molecular biology↗

The Heparan Sulfate Proteoglycan Syndecan-1 Influences Local Bone Cell Communication via the RANKL/OPG Axis

The heparan sulfate proteoglycan Syndecan-1, a mediator of signals between the extracellular matrix and cells involved is able to interact with OPG, one of the major regulators of osteoclastogenesis. The potential of osteoblasts to induce osteoclastogenesis is characterized by a switch of OPG (low osteoclastogenic potential) towards RANKL production (high osteoclastogenic potential). In the present study, we investigated the influence of endogenous Syndecan-1 on local bone-cell-communication via the RANKL/OPG-axis in murine osteoblasts and osteoclasts in wild type and Syndecan-1 lacking cells. Syndecan-1 expression and secretion was increased in osteoblasts with high osteoclastogenic potential. Syndecan-1 deficiency led to increased OPG release by osteoblasts that decreased the availability of RANKL. In co-cultures of Syndecan-1 deficient osteoblasts with osteoclast these increased OPG in supernatant caused decreased development of osteoclasts. Syndecan-1 and RANKL level were increased in serum of aged WT mice, whereas Syndecan-1 deficient mice showed high serum OPG concentration. However, bone structure of Syndecan-1 deficient mice was not different compared to wild type. In conclusion, Syndecan-1 could be regarded as a new modulator of bone-cell-communication via RANKL/OPG axis. This might be of high impact during bone regeneration or bone diseases like cancer where Syndecan-1 expression is known to be even more prevalent.

cell biology↗