Dataset Information

Wingless-type MMTV integration site family member 5a is a key inhibitor of islet stellate cells activation.

ABSTRACT:

Aims/introduction

Type 2 diabetes mellitus is a chronic metabolic disorder characterized by islet β-cell dysfunction, which might result from the activation of islet stellate cells (ISCs). Our recent study showed that a specific population of ISCs is prone to be activated in type 2 diabetes mellitus accompanied by reduced secretion of insulin. The wingless-type MMTV integration site family member 5a (Wnt5a)/frizzled-5 signaling pathway might play an important role in this process. The present study aimed to explore the effects of Wnt5a on the activation of ISCs isolated from db/db mice.

Materials and methods

ISCs were isolated from db/db mice and matched db/m mice. Immunohistochemistry and western blotting analysis were applied for the determination of Wnt5a expression. Exogenous Wnt5a and lentivirus containing the target gene Wnt5a short hairpin ribonucleic acid were used as a molecular intervention. The experiment of transwell and wound healing was used to evaluate the migration of the isolated ISCs.

Results

Our data showed that the expression of Wnt5a and frizzled-5 was decreased in the ISCs isolated from db/db mice compared with db/m mice. Both the exogenous Wnt5a and the overexpression of Wnt5a could inhibit the outgrowth rate of ISCs from islets, and its viability, migration and α smooth muscle actin expression. These changes were associated with the inactivation of the Smad2/3 signaling pathway in a frizzled-5-dependent manner.

Conclusions

Our observations revealed a potential role of Wnt5a in preventing ISC activation. The maintenance of quiescent ISCs might be a desirable outcome of therapeutic strategies for diabetes mellitus.

SUBMITTER: Xu W

PROVIDER: S-EPMC7078096 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:BackgroundIt has been demonstrated that activated islet stellate cells (ISCs) play a critical role in islet fibrogenesis and significantly contribute to the progression of type 2 diabetes mellitus. However, the key molecules responsible for ISCs activation have not yet been determined. This study aimed to identify the potential key genes involved in diabetes-induced activation of ISCs.MethodStellate cells were isolated from three 10-week-old healthy male Wistar rats and three Goto-Kakizaki (GK) rats. Cells from each rat were primary cultured under the same condition. A Genome-wide transcriptional sequence of stellate cells was generated using the Hiseq3000 platform. The identified differentially expressed genes were validated using quantitative real-time PCR and western blotting in GK rats, high fat diet (HFD) rats, and their controls.ResultsA total of 204 differentially expressed genes (DEGs) between GK. ISCs and Wistar ISCs (W.ISCs) were identified, accounting for 0.58% of all the 35,362 genes detected. After the Gene Ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analyses, the mRNA levels of these genes were further confirmed by real-time PCR in cultured ISCs. We then selected Fos, Pdpn, Bad as the potential key genes for diabetes-induced activation of ISCs. Finally, we confirmed the protein expression levels of FOS, podoplanin, and Bad by western blotting and immunofluorescence in GK rats, HFD rats, and their controls. The results showed that the expression level of FOS was significantly decreased, while podoplanin and Bad were significantly increased in GK.ISCs and HFD rats compared with controls, which were consistent with the expression of α-smooth muscle actin.ConclusionsA total of 204 DEGs were found between the GK.ISCs and W.ISCs. After validating the expression of potential key genes from GK rats and HFD rats, Fos, Pdpn, and Bad might be potential key genes involved in diabetes-induced activation of ISCs.

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