Chondrogenic potential and anti-senescence effect of hypoxia on canine adipose mesenchymal stem cells

Abstract

Mesenchymal stem cells (MSCs) have the ability to differentiate into multi-lineage cells, which confers great promise for use in regenerative medicine. In this study, canine adipose MSCs (cAD-MSCs) were isolated from canine adipose tissue. These cells clearly represented stemness (Oct4, Sox2, and Nanog) and differentiation potential into the mesoderm (adipocytes, chondrocytes, and osteoblasts) at early passages. The aim of this study was to evaluate the effects of hypoxia on the differentiation potential into mesoderm, and the expression of anti-apoptotic genes associated with cell survival for the optimal culturing of MSCs. We observed that the proliferation of the cAD-MSCs meaningfully increased when cultured under hypoxic condition than in normoxic condition, during 7 consecutive passages. Also, we found that hypoxia strongly expressed anti-senescence related genes such as HDAC1 (histone deacetylase 1), DNMT1 (DNA (cytosine-5)-methyltransferase 1), Bcl-2 (inhibitor of apoptosis), TERT (telomerase reverse transcriptase), LDHA (lactate dehydrogenase A), SLC2A1 (glucose transporter), and DKC1 (telomere holoenzyme complex) and differentiation potential of cAD-MSCs into chondrocytes, than seen under the normoxic culture conditions. We also examined the multipotency of hypoxic conditioned MSCs using quantitative real-time RT-PCR. We found that the expression levels of stemness genes such as Oct-4, Nanog, and Sox-2 were increased in hypoxic condition when compared to the normoxic condition. Collectively, these results suggest that hypoxic conditions have the ability to induce proliferation of MSCs and augment their chondrogenic potential. This study suggests that cell proliferation of cAD-MSC under hypoxia could be beneficial, when considering these cells for cell therapies of canine bone diseases.

Translational Animal Models Provide Insight Into Mesenchymal Stromal Cell (MSC) Secretome Therapy

“…A main goal of establishing a stable chondrocyte phenotype from dog MSCs is to increase their deposition of articular cartilage proteins, so that these cells can become an effective treatment option for chronic OA. For example, it was found that exposing canine AT-MSCs to hypoxic conditions resulted in increased proliferation, a downregulation of genes associated with senescence like histone acetylase 1 (HDAC 1) and DNAcytosine-5-methyltransferase (DNMT1), and an upregulation of genes that are associated with the potential to differentiate into chondrocytes like collagen type II alpha 1 (COL2A1) (Lee et al, 2016). Another study showed that culturing dog AT-MSCs with dimethyloxalylglycine (DMOG), which mimics hypoxic conditions by stabilizing hypoxia-inducible factor-1alpha (HIF1a), led to an increased expression of the signal protein vascular endothelial growth factor (VEGF), important in angiogenesis and thus, beneficial in diseases with ischemic conditions.…”

Enhancement of Chondrogenesis in Hypoxic Precondition Culture: A Systematic Review

“…In vitro study outcomes are summarized in Table 1. According to most studies, there were higher chondrogenic gene and protein expression including ACAN, Col1a1, Col1a2, Col2a1, and Sox9 [5], [9], [10], [11], [14], [15], [16], [17], [18], [19], [20], [21], [22], [23], [24], [25], [26], [27], [28], [29], [30], [31], [32], [33], [34], [35], [36], [37], [38], [39], [40], and higher extracellular matrix including Glycosaminoglycan (GAG) [5], [9], [10], [18], [19], [24], [25], [29], [31], [33], [38], [41], [42], higher expression of HIF-1α and HIF-2α [5], [17], …”

The in vitro human fracture hematoma model - a tool for preclinical drug testing_suppl

“…Although generally, cells rich in mitochondria often have an intrinsic need for sufficient oxygen supply and are barely able to cope with hypoxic conditions (e.g., neuronal cells), the survival capacity and activation status of immune cells (T cells, B cells, monocytes, neutrophils) is enhanced under hypoxic conditions, mainly due to activation/stabilization of the HIF-signaling pathway in an oxygen-restricted environment (Krzywinska and Stockmann, 2018). In terms of MSCs, hypoxia seems to favor MSC survival and their differentiation towards the chondrogenic and osteogenic lineages once differentiation is induced, while adipogenesis is reduced (Wagegg et al, 2012;Lee et al, 2016). However, whether inflammatory cells and MSCs actually differ in their tolerance of oxygen is still a matter of research.…”