Journal: Metabolism: clinical and experimental

Article Title: Serum Response Factor (SRF) promotes actin cytoskeletal organization in adipocytes to support adaptive hypertrophic expansion and tissue remodeling during obesity in mice

doi: 10.1016/j.metabol.2026.156548

Figure Lengend Snippet: Critical role of SRF in regulating actin cytoskeletal gene expression in adipocytes in vitro . (A) Motif identified by MEME that is enriched in H3K27ac peaks within the HFD-associated super-enhancer regions. (B) Alignment of the SRF binding motif identified de novo from SRF ChIP-Seq in TGFβ1-treated 3T3L1 adipocytes, compared to the canonical SRF motif from the HOMER database. (C) Pathway analysis of genes associated with SRF ChIP-seq peaks. (D) Genomic tracks showing SRF and H3K27ac ChIP-seq signals at the Acta2 locus, highlighting SRF binding induced by TGFβ1 treatment (indicated by a black arrow) within an adipocyte super-enhancer region. (E–G) In vitro loss- and gain-of function experiments in 3T3-L1 adipocytes. Gene expression analysis of cytoskeletal genes following (E) Srf knockdown ( shSrf , n = 3 per condition, total N = 6) and (F) overexpression ( Srf OE, n = 3 per condition, total N = 6). (G) Western blot analysis of SRF and ACTA2 protein levels upon Srf overexpression ( Srf OE, n = 2 per condition, total N = 4). A two-tailed Student’s t -test was used for statistical analysis. * P < 0.05, ** P < 0.01, *** P < 0.001.

Article Snippet: For generation of SRF knockout mice specific to beige and brown adipocytes (SRF-BKO), Srf -flox mice were crossed with Ucp1 -Cre mice (Jackson Laboratory, 024670).

Techniques: Gene Expression, In Vitro, Binding Assay, ChIP-sequencing, Knockdown, Over Expression, Western Blot, Two Tailed Test

Journal: Metabolism: clinical and experimental

Article Title: Serum Response Factor (SRF) promotes actin cytoskeletal organization in adipocytes to support adaptive hypertrophic expansion and tissue remodeling during obesity in mice

doi: 10.1016/j.metabol.2026.156548

Figure Lengend Snippet: Role of SRF in actin filament structure and cellular expansion in adipocytes in vivo during obesity. (A) Body weight trajectories of wild-type (WT, n = 11) and tamoxifen-inducible, adipocyte-specific Srf KO (SRF-AKO, n = 9) male mice during HFD feeding. Total N = 20. (B) Heatmap showing the relative expression of cytoskeletal and collagen genes in eWAT from WT ( n = 6) and SRF-AKO male mice ( n = 5). Total N = 11. (C) Phalloidin staining of actin filaments in isolated adipocytes from WT and SRF-AKO male mice (scale bar: 20 μm). (D–E) Co-staining of isolated adipocytes with phalloidin (red) and PLIN1 (green) from both eWAT and iWAT of female mice. Scale bar: 100 μm, with quantification of phalloidin signal intensity. (F–G) Representative H&E-stained adipose tissue sections from (F) eWAT and (G) iWAT of WT and SRF-AKO male mice, with quantification of average adipocyte size. Scale bar: 100 μm. A two-tailed Student’s t -test was used for statistical analysis. ** P < 0.01, *** P < 0.001, **** P < 0.0001.

Article Snippet: For generation of SRF knockout mice specific to beige and brown adipocytes (SRF-BKO), Srf -flox mice were crossed with Ucp1 -Cre mice (Jackson Laboratory, 024670).

Techniques: In Vivo, Expressing, Staining, Isolation, Two Tailed Test

Journal: Metabolism: clinical and experimental

Article Title: Serum Response Factor (SRF) promotes actin cytoskeletal organization in adipocytes to support adaptive hypertrophic expansion and tissue remodeling during obesity in mice

doi: 10.1016/j.metabol.2026.156548

Figure Lengend Snippet: Compromised structural integrity and increased cellular fragility in SRF-deficient adipocytes. (A) Basal and isoproterenol (ISO)-stimulated lipolysis, measured by glycerol release from 4-h eWAT and iWAT explants from WT and SRF-AKO male mice ( n = 3 per condition, total N = 12). (B) Representative transmission electron microscopy (TEM) images of eWAT from WT and SRF-AKO female mice, showing ruptured adipocyte membranes (indicated by black arrows). Scale bar: 5 μm. (C) Quantification of apoptotic cells in eWAT and iWAT from WT (eWAT, n = 3; iWAT, n = 5) and SRF-AKO (eWAT, n = 3; iWAT, n = 3) male mice by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining. (D) BODIPY staining of eWAT and iWAT from WT and SRF-AKO male mice following 1.5-h of compression. Scale bar: 100 μm. A two-tailed Student’s t -test was used for statistical analysis. * P < 0.05, ** P < 0.01.

Article Snippet: For generation of SRF knockout mice specific to beige and brown adipocytes (SRF-BKO), Srf -flox mice were crossed with Ucp1 -Cre mice (Jackson Laboratory, 024670).

Techniques: Transmission Assay, Electron Microscopy, TUNEL Assay, Staining, Two Tailed Test

Journal: Metabolism: clinical and experimental

Article Title: Serum Response Factor (SRF) promotes actin cytoskeletal organization in adipocytes to support adaptive hypertrophic expansion and tissue remodeling during obesity in mice

doi: 10.1016/j.metabol.2026.156548

Figure Lengend Snippet: Impaired vascular integrity and altered cell-cell communication in adipose tissue driven by loss of SRF in adipocytes. (A) UMAP visualization of 34,457 single nuclei isolated from eWAT and iWAT of WT and SRF-AKO male mice (total N = 4), with annotated cell types. (B) Violin plots of cell type-specific marker gene expression across all identified cell types. (C) Relative proportions of each cell type in eWAT and iWAT from WT and SRF-AKO male mice. (D–E) Whole-mount staining of eWAT from WT and SRF-AKO mice with Hoechst (blue), BODIPY (green), and either F4/80 (red, D) or PECAM1 (red, E). Scale bar: 100 μm. (F) Circle plots from CellChat analysis showing altered cell-cell communication in eWAT of SRF-AKO male mouse compared to WT. Increases in interaction number (left) and strength (right) are shown in red; decreases are shown in blue.

Article Snippet: For generation of SRF knockout mice specific to beige and brown adipocytes (SRF-BKO), Srf -flox mice were crossed with Ucp1 -Cre mice (Jackson Laboratory, 024670).

Techniques: Isolation, Marker, Gene Expression, Staining

Journal: Metabolism: clinical and experimental

Article Title: Serum Response Factor (SRF) promotes actin cytoskeletal organization in adipocytes to support adaptive hypertrophic expansion and tissue remodeling during obesity in mice

doi: 10.1016/j.metabol.2026.156548

Figure Lengend Snippet: Role of SRF in actin filament structure and cellular expansion in adipocytes in vivo during obesity. (A) Body weight trajectories of wild-type (WT, n = 11) and tamoxifen-inducible, adipocyte-specific Srf KO (SRF-AKO, n = 9) male mice during HFD feeding. Total N = 20. (B) Heatmap showing the relative expression of cytoskeletal and collagen genes in eWAT from WT ( n = 6) and SRF-AKO male mice ( n = 5). Total N = 11. (C) Phalloidin staining of actin filaments in isolated adipocytes from WT and SRF-AKO male mice (scale bar: 20 μm). (D–E) Co-staining of isolated adipocytes with phalloidin (red) and PLIN1 (green) from both eWAT and iWAT of female mice. Scale bar: 100 μm, with quantification of phalloidin signal intensity. (F–G) Representative H&E-stained adipose tissue sections from (F) eWAT and (G) iWAT of WT and SRF-AKO male mice, with quantification of average adipocyte size. Scale bar: 100 μm. A two-tailed Student’s t -test was used for statistical analysis. ** P < 0.01, *** P < 0.001, **** P < 0.0001.

Article Snippet: To generate inducible adipocyte-specific SRF knockout (SRF-AKO) mice, Srf -flox mice (Jackson Laboratory, 006658) were crossed with Adipoq -CreERT2 mice (Jackson Laboratory, 024671).

Techniques: In Vivo, Expressing, Staining, Isolation, Two Tailed Test

Journal: Metabolism: clinical and experimental

Article Title: Serum Response Factor (SRF) promotes actin cytoskeletal organization in adipocytes to support adaptive hypertrophic expansion and tissue remodeling during obesity in mice

doi: 10.1016/j.metabol.2026.156548

Figure Lengend Snippet: Impaired systemic glucose homeostasis and partial lipodystrophy phenotype in SRF-AKO mice during obesity. (A–C) Defective glucose homeostasis in SRF-AKO ( n = 9) compared to WT ( n = 11) male mice during obesity (total N = 20), assessed by (A) glucose tolerance test (GTT, 1 g/kg body weight glucose), (B) insulin tolerance test (ITT, 1 U/kg body weight insulin), and (C) fasting insulin levels (ng/mL) relative to body weight. (D) Tissue weight (% of body weight) of eWAT, iWAT, and BAT, and liver in WT ( n = 11) and SRF-AKO ( n = 9) male mice. Total N = 20. (E–F) Representative H&E-stained sections of (E) BAT and (F) liver from WT and SRF-AKO male mice. Scale bar: 100 μm. A two-tailed Student’s t -test was used for statistical analysis. * P < 0.05, ** P < 0.01.

Article Snippet: To generate inducible adipocyte-specific SRF knockout (SRF-AKO) mice, Srf -flox mice (Jackson Laboratory, 006658) were crossed with Adipoq -CreERT2 mice (Jackson Laboratory, 024671).

Techniques: Staining, Two Tailed Test

Journal: Metabolism: clinical and experimental

Article Title: Serum Response Factor (SRF) promotes actin cytoskeletal organization in adipocytes to support adaptive hypertrophic expansion and tissue remodeling during obesity in mice

doi: 10.1016/j.metabol.2026.156548

Figure Lengend Snippet: Compromised structural integrity and increased cellular fragility in SRF-deficient adipocytes. (A) Basal and isoproterenol (ISO)-stimulated lipolysis, measured by glycerol release from 4-h eWAT and iWAT explants from WT and SRF-AKO male mice ( n = 3 per condition, total N = 12). (B) Representative transmission electron microscopy (TEM) images of eWAT from WT and SRF-AKO female mice, showing ruptured adipocyte membranes (indicated by black arrows). Scale bar: 5 μm. (C) Quantification of apoptotic cells in eWAT and iWAT from WT (eWAT, n = 3; iWAT, n = 5) and SRF-AKO (eWAT, n = 3; iWAT, n = 3) male mice by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining. (D) BODIPY staining of eWAT and iWAT from WT and SRF-AKO male mice following 1.5-h of compression. Scale bar: 100 μm. A two-tailed Student’s t -test was used for statistical analysis. * P < 0.05, ** P < 0.01.

Article Snippet: To generate inducible adipocyte-specific SRF knockout (SRF-AKO) mice, Srf -flox mice (Jackson Laboratory, 006658) were crossed with Adipoq -CreERT2 mice (Jackson Laboratory, 024671).

Techniques: Transmission Assay, Electron Microscopy, TUNEL Assay, Staining, Two Tailed Test

Journal: Metabolism: clinical and experimental

Article Title: Serum Response Factor (SRF) promotes actin cytoskeletal organization in adipocytes to support adaptive hypertrophic expansion and tissue remodeling during obesity in mice

doi: 10.1016/j.metabol.2026.156548

Figure Lengend Snippet: Impaired vascular integrity and altered cell-cell communication in adipose tissue driven by loss of SRF in adipocytes. (A) UMAP visualization of 34,457 single nuclei isolated from eWAT and iWAT of WT and SRF-AKO male mice (total N = 4), with annotated cell types. (B) Violin plots of cell type-specific marker gene expression across all identified cell types. (C) Relative proportions of each cell type in eWAT and iWAT from WT and SRF-AKO male mice. (D–E) Whole-mount staining of eWAT from WT and SRF-AKO mice with Hoechst (blue), BODIPY (green), and either F4/80 (red, D) or PECAM1 (red, E). Scale bar: 100 μm. (F) Circle plots from CellChat analysis showing altered cell-cell communication in eWAT of SRF-AKO male mouse compared to WT. Increases in interaction number (left) and strength (right) are shown in red; decreases are shown in blue.

Article Snippet: To generate inducible adipocyte-specific SRF knockout (SRF-AKO) mice, Srf -flox mice (Jackson Laboratory, 006658) were crossed with Adipoq -CreERT2 mice (Jackson Laboratory, 024671).

Techniques: Isolation, Marker, Gene Expression, Staining

Journal: JACC: Basic to Translational Science

Article Title: HDL Regulates TGFβ-Receptor Lipid Raft Partitioning, Restoring Contractile Features of Cholesterol-Loaded Vascular Smooth Muscle Cells

doi: 10.1016/j.jacbts.2025.101461

Figure Lengend Snippet: Contractile Gene Expression Is Downregulated in Chol-Loaded hVSMCs (A, B) Human vascular smooth muscle cells (hVSMCs) were treated with cholesterol (Chol) (5 μg/mL) or 0.2% bovine serum albumin (control [CT]) for 24 hours and 48 hours and gene expression of Acta2 , Tagln , Cnn1, Myocd, and Srf were determined by quantitative polymerase chain reaction. (C) hVSMCs were treated with Chol (5 μg/mL) or 0.2% bovine serum albumin (CT) for 24 hours and protein expression of α–smooth muscle actin (α-SMA) and CNN1 were determined by Western blotting (representative blots shown). Densitometry showing the (D) α-SMA and (E) CNN1 band intensities normalized to GAPDH. For data analysis, unpaired Student’s t -testing was performed for comparing the means of 2 groups. For 2 or more independent groups, 1-way analysis of variance followed by Dunnett post hoc test was performed. A P value of ≤0.05 was considered significant. Data are presented as the mean ± SEM of 3 independent experiments, and P values are as indicated (∗ P < 0.05, ∗∗ P < 0.01, ∗∗∗∗ P < 0.0001).

Article Snippet: The primary antibodies used were as follows: ACTA2 (#A2547, Sigma); CNN1 (#M3556, DAKO); SRF (#5147, Cell Signaling); p38MAPK (#sc-535, Santa Cruz Biotechnology); SMAD2/3 (#8685, Cell Signaling); TUBA (#T-5168, Sigma); and SMAD2 (#3103, Cell Signaling), phospho-SMAD2 (#3101S, Cell Signaling), phospho-p38MAPK (#9211S, Cell Signaling), SMAD4 (#9515, Cell Signaling); CD68 (#MCA1815, AbD Serotec, Bio-Rad); KLF4 (#12173, Cell Signaling); PU.1 (#sc-352, Santa Cruz Biotechnology); TGFβR1 (#3712, Cell Signaling); TGFβR2 (#sc-400, Santa Cruz Biotechnology); Caveolin (#610059, BD Transduction Laboratories); CD71 (#13113, Cell Signaling); GAPDH (#AM4300, Ambion).

Techniques: Gene Expression, Control, Real-time Polymerase Chain Reaction, Expressing, Western Blot

Journal: JACC: Basic to Translational Science

Article Title: HDL Regulates TGFβ-Receptor Lipid Raft Partitioning, Restoring Contractile Features of Cholesterol-Loaded Vascular Smooth Muscle Cells

doi: 10.1016/j.jacbts.2025.101461

Figure Lengend Snippet: Chol-Loading Downregulates TGFβ Signaling in hVSMC hVSMCs were treated with Chol (5 μg/mL) or 0.2% bovine serum albumin (CT; ie, 0 μg/mL cholesterol) for 24 hours in the presence or absence of TGFβ1 ligand (10 pg/mL). Total RNA was isolated and quantitative polymerase chain reaction (qPCR) was performed to determine the pri-Mir143/145 precursor transcripts (A,B) or SMC markers, Acta2 and Tagln (C,D). hVSMCs were treated as in A and B, but either in the presence or absence of TGFβ1 10 pg/mL) and/or nonscrambled (NS) or Mir145 mimic (60 nmol/L). qPCR was performed to determine expression of Acta2 (E) and (F) Srf mRNA. (G) hVSMCs were treated as in A and B, but either in the presence or in absence of TGFβ1 (10 pg/mL) and/or Mir145 inhibitor (60 nmol/L). qPCR was performed to determine expression of Acta2. (H) Immunofluorescence images of total SMAD2/3 (green) in hVSMCs after 24 hours of the indicated treatments. Cytoplasm was stained with phalloidin (red). Nuclei were determined as phalloidin negative area (bar = 50 μm). (I) hVSMCs were treated as in A and B, but with varying amounts of Chol and in the presence or absence of recombinant TGFβ1 (10 pg/mL) for 24 hours. Proteins were extracted for Western blotting to detect phosphorylated (p) SMAD2/3, and α-SMA. Total SMAD2/3 or GAPDH was used as loading CT proteins. Blots are representative of at least 3 independent experiments, and the replicates were quantified by densitometry. For data comparisons of 2 or more independent groups, 1-way or 2-way analysis of variance followed by Dunnett post hoc test was performed. Data are presented as the mean ± SEM of 3 independent experiments, and P values are as indicated (∗ P < 0.05, ∗∗ P < 0.01, ∗∗∗ P < 0.001, ∗∗∗∗ P < 0.0001). ns = not significant; other abbreviations as in .

Article Snippet: The primary antibodies used were as follows: ACTA2 (#A2547, Sigma); CNN1 (#M3556, DAKO); SRF (#5147, Cell Signaling); p38MAPK (#sc-535, Santa Cruz Biotechnology); SMAD2/3 (#8685, Cell Signaling); TUBA (#T-5168, Sigma); and SMAD2 (#3103, Cell Signaling), phospho-SMAD2 (#3101S, Cell Signaling), phospho-p38MAPK (#9211S, Cell Signaling), SMAD4 (#9515, Cell Signaling); CD68 (#MCA1815, AbD Serotec, Bio-Rad); KLF4 (#12173, Cell Signaling); PU.1 (#sc-352, Santa Cruz Biotechnology); TGFβR1 (#3712, Cell Signaling); TGFβR2 (#sc-400, Santa Cruz Biotechnology); Caveolin (#610059, BD Transduction Laboratories); CD71 (#13113, Cell Signaling); GAPDH (#AM4300, Ambion).

Techniques: Isolation, Real-time Polymerase Chain Reaction, Expressing, Immunofluorescence, Staining, Recombinant, Western Blot