Deer antler extract potentially facilitates xiphoid cartilage growth and regeneration and prevents inflammatory susceptibility by regulating multiple functional genes

Abstract

Background: Deer antler is a zoological exception due to its fantastic characteristics, including amazing growth rate and repeatable regeneration. Deer antler has been used as a key ingredient in traditional Chinese medicine relating to kidney and bone health for centuries. The aim of this study was to dissect the molecular regulation of deer antler extract (DAE) on xiphoid cartilage (XC).

Methods: The DAE used in this experiment was same as the one that was prepared as previously described. The specific pathogen-free (SPF) grade Sprague-Dawley (SD) rats were randomly divided into blank group (n =10) and DAE group (n =10) after 1-week adaptive feeding. The DAE used in this experiment was same as the one that was prepared as previously described. The rats in DAE group were fed with DAE for 3 weeks at a dose of 0.2 g/kg per day according to the body surface area normalization method, and the rats in blank group were fed with drinking water. Total RNA was extracted from XC located in the most distal edge of the sternum. Illumina RNA sequencing (RNA-seq) in combination with quantitative real-time polymerase chain reaction (qRT-PCR) validation assay was carried out to dissect the molecular regulation of DAE on XC.

Results: We demonstrated that DAE significantly increased the expression levels of DEGs involved in cartilage growth and regeneration, but decreased the expression levels of DEGs involved in inflammation, and mildly increased the expression levels of DEGs involved in chondrogenesis and chondrocyte proliferation.

Conclusions: Our findings suggest that DAE might serve as a complementary therapeutic regent for cartilage growth and regeneration to treat cartilage degenerative disease, such as osteoarthritis.

Keywords: Deer antler extract; Growth; Molecular regulation; RNA sequencing; Regeneration; Xiphoid cartilage.

Fig. 1

GO enrichment analysis of XC under DAE treatment. The x-axis indicates the number of mapped genes in a category, and the x-axis indicates the significantly enriched GO terms (p <0.05) in different categories including cellular component, molecular function, and biological process

Fig. 2

KEGG enrichment analysis of XC under DAE treatment. The x-axis indicates the rich factor that is presented by the ratio of DEG number in the total gene number of a defined pathway, and the x-axis indicates the name of enriched pathway. The color of the dots represents the range of the Q value, and the size of the dots represents the number of DEGs mapped to a defined pathway, respectively

Fig. 3

Validation of RNA-seq data by qRT-PCR. The relative expression data with their corresponding error bars were derived from three technical replicates in an experiment representative of several independent ones. The asterisk *, **, and *** indicate levels of significance of differential expression tested by Student’s t test with p value <0.05, <0.01, and <0.001, respectively. Gene expression level for each gene is calculated as the fold change of the DAE group to the blank group