Transcriptomic Profiling of Subcutaneous Adipose Tissue in Relation to Bariatric Surgery: A Retrospective, Pooled Re-analysis.

Background: Bariatric surgery is the most effective intervention for weight loss possibly through modulating subcutaneous adipose tissue (SAT) molecular programs. The post-operative molecular and biological impacts, including gene expression, deserve in-depth investigation especially given the small sample sizes in the literature.

Methods: Five existing datasets (n=237 SATs) were re-processed and corrected for batch-to-batch variation. Unsupervised approaches and robust linear mixed effect model were used to compare gene expression post- (n=126) to pre-operation (n=111).

Results: Post-operative SATs showed distinct global gene expression. Forty-four and 395 genes were over- and under-expressed post-operation (all Bonferroni P<0.05). The under-expressed genes significantly enriched for 21 biological processes/pathways (all Bonferroni P<0.05), 17 (76.2%) and two (9.5%) directly involved in immunity and amino/proteo-glycan metabolism, respectively.

Conclusion: Post-operative SATs might adopt distinct transcriptomic landscapes and undergo a reduction in immune-related processes and amino/proteo-glycan metabolism.