Conclusions
MetS upregulates the TNF-α transcriptome and proteome in swine adipose tissue-derived MSCs, which are partly transmitted to their EV progeny, and are associated with activation of NF-kB in target cells. Hence, the MetS milieu may affect the profile of endogenous MSCs and their paracrine vectors and limit their use as an exogenous regenerative therapy. Anti-inflammatory strategies targeting the TNF-α pathway might be a novel strategy to restore MSC phenotype, and in turn function.
Methods
Domestic pigs were fed a 16-week Lean or MetS diet (n = 4 each). MSCs were harvested from abdominal subcutaneous fat, and their extracellular vesicles (EVs) isolated. Expression profiles of mRNAs and proteins in MSCs and EVs were obtained by high-throughput sequencing and proteomics. Nuclear translocation of the pro-inflammatory transcription factor (NF)-kB was evaluated in MSC and in pig renal tubular cells (TEC) co-incubated with EVs.
Results
We found 13 mRNAs and 4 proteins in the TNF-α pathway upregulated in MetS- vs. Lean-MSCs (fold-change > 1.4, p < 0.05), mostly via TNF-α receptor-1 (TNF-R1) signaling. Three mRNAs were upregulated in MetS-EVs. MetS-MSCs, as well as TECs co-incubated with MetS-EVs, showed increased nuclear translocation of NF-kB. Using qPCR, JUNB, MAP2K7 and TRAF2 genes followed the same direction of RNA-sequencing findings. Conclusions: MetS upregulates the TNF-α transcriptome and proteome in swine adipose tissue-derived MSCs, which are partly transmitted to their EV progeny, and are associated with activation of NF-kB in target cells. Hence, the MetS milieu may affect the profile of endogenous MSCs and their paracrine vectors and limit their use as an exogenous regenerative therapy. Anti-inflammatory strategies targeting the TNF-α pathway might be a novel strategy to restore MSC phenotype, and in turn function.