Hyperglycemia Impairs Skeletogenesis from Embryonic Stem Cells by Affecting Osteoblast and Osteoclast Differentiation

Abstract

High maternal blood glucose levels caused by diabetes mellitus can irreversibly lead to maldevelopment of the growing fetus with specific effects on the skeleton. To date, it remains controversial at which stage embryonic development is affected. Specifically during embryonic bone development, it is unclear whether diminished bone mineral density is caused by reduced osteoblast or rather enhanced osteoclast function. Therefore, the aim of this study was to characterize the growth as well as the skeletal differentiation capability of pluripotent embryonic stem cells (ESCs), which may serve as an in vitro model for all stages of embryonic development, when cultured in diabetic levels of D-glucose (4.5 g/L) versus physiological levels (1.0 g/L). Results showed that cells cultivated in physiological glucose gave rise to a higher number of colonies with an undifferentiated character as compared to cells grown in diabetic glucose concentrations. In contrast, these cultures were characterized by slightly decreased expression of proteins associated with the stem cell state. Furthermore, differentiation of ESCs into osteoblasts and osteoclasts was favored in physiological glucose concentrations, demonstrated by an increased matrix calcification, enhanced expression of cell-type-specific mRNAs, as well as activity of the cell-type-specific enzymes, alkaline, and tartrate resistant acidic phosphatase. In fact, this pattern was noted in murine as well as in primate ESCs. Our study suggests that an interplay between both the osteoblast and the osteoclast lineage is needed for proper skeletal development to occur, which seems impaired in hyperglycemic conditions.

Delayed bone regeneration and low bone mass in a rat model of insulin-resistant type 2 diabetes mellitus is due to impaired osteoblast function

“…We did not observe altered osteoclast functions ex vivo, in contrast to other reports, which suggested that a diabetic microenvironment tends to inhibit osteoclast differentiation and function (30,16,29,4,12). However, none of these studies used an in vivo model of rats with type 2 diabetes mellitus.…”

Decreased osteoclastogenesis, osteoblastogenesis and low bone mass in a mouse model of type 2 diabetes

“…In vivo, Kawashima et al (17) found evidence supporting increased osteoclastogenesis in the diabetic bone microenvironment (17). In vitro, Huang et al (18) reported that an elevated insulin environment negatively regulated osteoclast differentiation and the expression of RANK and c-fos (18), and these results were corroborated by a study by Dienelt and zur Nieden (19). The data from the present study suggest that bone resorption was impaired in the T2DM model due to impaired osteoclast function.…”

Heat shock protein production and immunity and altered fetal development in diabetic pregnant rats

“…In addition, the malformation rate is clearly correlated with increased glucose concentrations (Jawerbaum and White 2010). Experimental results support the notion of hyperglycemia as a teratogen, since high glucose levels (Dienelt and Zur Nieden 2011) or maternal diabetes in vivo as well as exposure to high glucose concentration cause embryonic maldevelopment. Several studies have shown that fetuses from mild diabetic rats have a compromised intrauterine development (Saito et al 2010;Iessi et al 2010) and elevated oxidative stress, contributing to an increased incidence of skeletal and visceral malformations at birth .…”