Adipokines, Inflammation, and Metabolic Diseases · Journal article

Transcriptomic Analysis of Bone Marrow Adipose Tissue Reveals Enrichment in Lipid Transport in Response to Western Diet

Endocrinology · August 14, 2026

Preliminary Why this matters to you Expert discussion

Early or partial results. Treat as a signal, not a conclusion.

AI Summary

This is a single-centre, uncontrolled animal transcriptomic study showing that a 12-week Western diet induces differential gene expression in rat bone marrow adipose tissue compared to gonadal white adipose tissue, with enrichment in lipid transport pathways in BMAT. The findings are mechanistic and exploratory, providing a hypothesis about BMAT's role in nutrient sensing but lacking clinical endpoints or confirmation in independent cohorts.

What was studied

Experimental animal study with controlled dietary intervention and bulk RNA-sequencing. 20-week-old Sprague-Dawley rats; eligibility criteria not specified.. Intervention: Western diet (42% kJ fat) for 12 weeks.. Compared with: Chow diet (12% kJ fat).. Not stated..

Key findings

Western diet significantly increased body weight (P = 0.02) and whole-body fat percentage (P = 0.009) in rats Adipocyte size increased in humeral BMAT (P = 0.02) and gonadal WAT (P = 0.005) with Western diet BMAT transcriptome showed enrichment in lipid transport pathways in response to Western diet, whereas WAT showed enrichment in lipid biosynthesis and modification

Safety

Safety was not reported in the material analysed. Check the source before drawing any conclusion about harm.

Who this may help

This preclinical finding suggests BMAT may have a distinct metabolic role in lipid uptake during high-fat feeding, distinct from WAT. However, translation to human disease requires confirmation in clinical studies with metabolic and clinical outcomes.

Plain-language summary

Single-site animal study with transcriptomic endpoints and no clinical outcomes; mechanistic findings in rats require confirmation and clinical translation.

Study design

As stated by the source record.

MethodsSprague-Dawley rats aged 20 weeks were fed either chow diet (12% kJ fat) or Western diet (42% kJ fat) for 12 weeks. Transcriptomes of femoral and tibial BMAT and gonadal WAT were profiled using bulk RNA-sequencing. Gene-set enrichment analysis was performed to identify over-represented pathways. Phenotypic measures including body weight, whole-body fat percentage, and adipocyte size were compared between diet groups.

DesignExperimental animal study with controlled dietary intervention and bulk RNA-sequencing

Population20-week-old Sprague-Dawley rats; eligibility criteria not specified.

InterventionWestern diet (42% kJ fat) for 12 weeks.

ComparatorChow diet (12% kJ fat).

SettingNot stated.

Reported figures

Quoted from the source exactly as published.

Body weight increase with Western dietP = 0.02

Whole-body fat percentage increase with Western dietP = 0.009

Adipocyte size increase in humeral BMATP = 0.02

Adipocyte size increase in gonadal WATP = 0.005

Dietary fat content chow12%kJ fat

Dietary fat content Western diet42%kJ fat

Dietary intervention duration12 weeks

Clinical bottom line

Caveats

No sample size per group explicitly reported; total N across both diet groups not stated
No blinding, randomization process, or allocation concealment described
Gene expression (transcriptomics) is a surrogate endpoint; no metabolic or clinical outcomes measured
Findings limited to rat model; human applicability unknown

Evidence assessment

Graded across the dimensions that decide whether you should act, each from what the source actually supports. There is no single score, and where a dimension was not assessed it says so.

Study design

moderate

Controlled dietary intervention with transcriptomic analysis; animal model limits generalizability.

Directness

limited

Gene expression changes in rat bone marrow; clinical relevance to human obesity unclear.

Consistency

insufficient

Single study; no comparison to prior transcriptomic analyses of BMAT in diet intervention.

Risk of bias

moderate

No mention of blinding, randomization, or pre-registration; standard animal study conduct not detailed.

Sample adequacy

moderate

20-week-old rats in two groups; sample size per group not explicitly stated.

Source abstract

Bone marrow adipose tissue (BMAT) is now recognised as a functional fat depot distinct from extramedullary white- (WAT) and brown (BAT) adipose tissues. BMAT expands in metabolic disorder such as obesity. However, the mechanism by which BMAT expands is less clear. Here, we present a comparative analysis of the transcriptomes of BMAT, WAT and BAT from 20-week-old Sprague-Dawley rats fed with chow diet (12%kJ fat) using bulk-RNA-sequencing. Gene-set enrichment analysis revealed over-representation of transcripts related to cellular proliferation and population of adipoprogenitor cells in BMAT. To further study BMAT expansion, we introduced a 12-week dietary intervention of Western diet (42%kJ fat). We first characterised obesity-related phenotypes such as adipocyte hypertrophy. Then, we compared the transcriptomes of femoral and tibial BMAT or gonadal WAT to the chow group. Western diet significantly increased bodyweight (P = 0.02), whole-body fat percentage (P = 0.009) and adipocyte size in humeral BMAT (P = 0.02) and gonadal WAT (P = 0.005), in comparison to the chow group. BMAT had a more robust transcriptomic response to Western diet than WAT. The transcriptome of BMAT was enriched in pathways related to lipid transport. In WAT, this enrichment was more related to lipid biosynthesis and modification. In summary, our data may suggest differences in the developmental maturity of BMAT relative to WAT and BAT in the chow group. Western diet induces differential responses in the transcriptomes of BMAT and WAT related to lipid homeostasis. In BMAT, enrichment in the lipid transport pathways upon Western diet may suggest a role for BMAT in nutrient-sensing and lipid uptake.

Follow from this

Taken from the source record, never inferred. Follow any of these and new work involving them reaches your briefing.

Kaisa K. IvaskaNicko WidjajaLeena StraussAdipokines, Inflammation, and Metabolic DiseasesKirsi A VirtanenNiki Jalava