Journal: bioRxiv

Article Title: Activation of PPARγ redirects fibro-adipogenic progenitors to replace ectopic bone with fat in models of fibrodysplasia ossificans progressiva and trauma-induced heterotopic ossification

doi: 10.64898/2026.02.26.708276

Figure Lengend Snippet: (A) X-ray and Micro-CT imaging revealed a greater volume of ectopic bone in the hindlimbs of FOP mice treated with the corn oil vehicle control compared to those treated with rosiglitazone. (B) Quantification of ectopic bone showed an approximately 10-fold decrease in ectopic bone volume following rosiglitazone treatment. (n = 8) Statistical significance between two groups was determined using Student’s t -test ( p < 0.05). (C) H&E, Picrosirius Red, and Safranin-O/Fast Green staining of FOP mouse hindlimbs showed a reduction in FOP lesions and an increase in soft tissue–resident adipocytes after rosiglitazone treatment. Chondrocytes are represented by the red staining of Saffranin-O whereas the Fast Green stain represents the bone. (D) Immunofluorescence imaging of rosiglitazone-treated FOP mice showed an increase in soft tissue–resident adipocytes, indicated by PPARγ and Perilipin-1–positive cells. In contrast, hindlimbs of control mice exhibited adipogenic signals only within the bone marrow, consistent with bone marrow–resident adipocytes. Soft tissue–resident adipocytes were absent in control mice. pSMAD1/5 staining revealed abundant positive cells in the bone marrow of control mice and in the soft tissue of rosiglitazone-treated mice. Soft tissue resident adipocytes were also positive for PDGFRα, suggesting that the adipocytes were derived from FAPs.

Article Snippet: The sections were probed with antibodies for Perilipin-1 (Cell Signaling Technology, cat# 3467S, 1:100), PPARγ (Proteintech, cat 16643-1-AP, 1:100), pSMAD1/5 (Cell Signaling Technology, cat# 9516S, 1:100).

Techniques: Micro-CT, Imaging, Control, Staining, Immunofluorescence, Derivative Assay

Journal: bioRxiv

Article Title: Activation of PPARγ redirects fibro-adipogenic progenitors to replace ectopic bone with fat in models of fibrodysplasia ossificans progressiva and trauma-induced heterotopic ossification

doi: 10.64898/2026.02.26.708276

Figure Lengend Snippet: (A) Schematic representation of the procedure used to induce heterotopic ossification (HO) in wild-type (WT) mice via Achilles tendon tenotomy. Tissue was harvested 3 weeks post tenotomy. (B) Micro-CT imaging showed ectopic bone in the soft tissue and surrounding the calcaneus of the right hindlimb where tenotomy was performed. (C) H&E and Safranin-O/Fast Green staining of tenotomized WT mice showed a reduction in HO lesions and an increase in soft tissue–resident adipocytes following rosiglitazone treatment. (D) Immunofluorescence imaging of rosiglitazone-treated tenotomy mice revealed an increase in soft tissue–resident adipocytes, indicated by PPARγ and Perilipin-1–positive cells. In contrast, control mice displayed adipogenic signals only within the bone marrow, consistent with bone marrow–resident adipocytes. Soft tissue–resident adipocytes were absent in control mice. pSMAD1/5 staining showed abundant positive cells in the bone marrow of control mice and in the soft tissue of rosiglitazone-treated mice.

Article Snippet: The sections were probed with antibodies for Perilipin-1 (Cell Signaling Technology, cat# 3467S, 1:100), PPARγ (Proteintech, cat 16643-1-AP, 1:100), pSMAD1/5 (Cell Signaling Technology, cat# 9516S, 1:100).

Techniques: Micro-CT, Imaging, Staining, Immunofluorescence, Control

Journal: bioRxiv

Article Title: Activation of PPARγ redirects fibro-adipogenic progenitors to replace ectopic bone with fat in models of fibrodysplasia ossificans progressiva and trauma-induced heterotopic ossification

doi: 10.64898/2026.02.26.708276

Figure Lengend Snippet: (A) Schematic representation of the procedure used to induce heterotopic ossification (HO) in wild-type (WT) mice via Achilles tendon tenotomy, followed by local rosiglitazone injection. Tissue was harvested 3 weeks post tenotomy. (B) H&E and Safranin-O/Fast Green staining of tenotomized WT mice showed a reduction in HO lesions and an increase in soft tissue–resident adipocytes after rosiglitazone treatment. (C) Immunofluorescence imaging of rosiglitazone-treated tenotomy mice revealed an increase in soft tissue–resident adipocytes, as indicated by PPARγ and Perilipin-1–positive cells. In contrast, control mice showed adipogenic signals only within the bone marrow, consistent with bone marrow–resident adipocytes, while soft tissue–resident adipocytes were absent. pSMAD1/5 staining showed abundant positive cells in the bone marrow of control mice and in the soft tissue of rosiglitazone-treated mice.

Article Snippet: The sections were probed with antibodies for Perilipin-1 (Cell Signaling Technology, cat# 3467S, 1:100), PPARγ (Proteintech, cat 16643-1-AP, 1:100), pSMAD1/5 (Cell Signaling Technology, cat# 9516S, 1:100).

Techniques: Injection, Staining, Immunofluorescence, Imaging, Control

Journal: Biomolecules

Article Title: Impaired TGFβ Signaling in Plaque-Associated Microglia

doi: 10.3390/biom16020248

Figure Lengend Snippet: Distribution of pSMADs 1, 5, and 8 in microglia. ( a – c ) Representative confocal images from cortices showing phosphorylated SMADs1, 5, and 8 ((pSMAD1/5/8, red, ( a’’ – c’’ )) in 6-month WT, 24-month WT, and 24-month APP/PS1 mice. Microglia are labeled with Iba-1 ((green, ( a’ – c’ )) and nuclei with DAPI (blue, ( a – c )); merged images are shown in ( a’’’ – c’’’ ). ( a’’’’ – c’’’’ ) show overlay of pSMADs 1, 5, and 8 and DAPI signal of microglia. ( d , e ) Quantification of cytoplasmic and nuclear pSMAD CTCF within Iba-1 + microglia. ( f ) Nuclear/cytoplasmic (N/C) pSMAD ratios per cell (values >1 indicate nuclear enrichment; <1 indicate cytoplasmic predominance). Statistical significance was assessed by one-way ANOVA with Tukey’s post hoc test. The nuclear-to-cytoplasmic pSMAD1/5/8 CTCF ratio was analyzed using a Kruskal–Wallis test followed by Dunn’s multiple comparisons test. Significance: ** p < 0.01, *** p < 0.001; ns—not significant.

Article Snippet: pSMAD1/5/8 , mono , 1:800 , Rabbit , Cell Signaling Technology, Danvers, MA, USA , 13820.

Techniques: Labeling

Journal: Biomolecules

Article Title: Impaired TGFβ Signaling in Plaque-Associated Microglia

doi: 10.3390/biom16020248

Figure Lengend Snippet: Proposed model of TGF-β/SMAD signaling in physiologic versus AD microglia. Left , Physiologic microglia: TGF-β1 engages its receptors, leading to SMAD phosphorylation and balanced nuclear accumulation of pSMAD2 (red dots) and pSMAD1/5/8 (blue dots). Nuclear SMAD complexes cooperate with transcription factors to drive neuroprotective, anti-inflammatory gene programs. Right , AD microglia: despite increased extracellular TGF-β1 and receptor engagement, pSMAD2 shows predominant cytoplasmic retention with comparatively weaker nuclear accumulation, resulting in reduced transcriptional output and diminished anti-inflammatory effects; pSMAD1/5/8 remains detectable. Insets depict representative microglial morphologies in the respective conditions. The graphic was designed with Microsoft PowerPoint.

Article Snippet: pSMAD1/5/8 , mono , 1:800 , Rabbit , Cell Signaling Technology, Danvers, MA, USA , 13820.

Techniques: Phospho-proteomics