Journal: Science Advances

Article Title: Piezo1 regulates the regenerative capacity of skeletal muscles via orchestration of stem cell morphological states

doi: 10.1126/sciadv.abn0485

Figure Lengend Snippet: ( A ) Increased protrusion length in all types of Piezo1 MuSC-KO MuSCs under steady-state conditions. ( B ) Cells are elongated in Piezo1 MuSC-KO compared to control muscles under steady-state conditions. ( C ) Reduced number of responsive cells and increased number of sensory cells in Piezo1 MuSC-KO muscles under steady-state conditions. ( D ) Representative images of Piezo1 MuSC-KO MuSCs show the complexity of the protrusions in these cells. Scale bars, 10 μm. ( E ) Schematic representation of seven intraperitoneal tamoxifen (Tam) injections and then notexin (ntx) injection 3 weeks after the last tamoxifen injection. Imaging of the TA muscle at d3 post-notexin injury using two-photon microscopy of control (gray) and Piezo1 MuSC-KO (red) mice. ( F ) Significantly reduced number of responsive cells and excessive number of sensory cells (red columns) in Piezo1 MuSC-KO muscles at d3 after injury, a time point that control muscles have negligible numbers of sensory cells (gray columns). n = 3 mice (3 months old) were analyzed, and N > 600 cells per animal. Two-way ANOVA was used for analyses, followed by Šídák’s multiple comparisons test. * P < 0.05, ** P < 0.01, *** P < 0.001, and **** P < 0.0001.

Article Snippet: Primers were purchased from Applied Biosystems and included Piezo1-FAM (Mm012415449_m1) and GAPDH-VIC (4352339e).

Techniques: Control, Muscles, Injection, Imaging, Microscopy

Journal: Science Advances

Article Title: Piezo1 regulates the regenerative capacity of skeletal muscles via orchestration of stem cell morphological states

doi: 10.1126/sciadv.abn0485

Figure Lengend Snippet: ( A ) Representative maximum intensity projections of an uninjured Pax7EGFP (left) and dystrophic (mdx/Pax7EGFP) muscle (right) at 3 months old. Note the increased number and complexity of protrusions in the dystrophic compared to uninjured muscles. Pax7EGFP MuSCs are shown in green. Scale bars, 50 μm. ( B ) qRT-PCR of Piezo1 gene in control (cntr) (black) and dystrophic (dystr.) (blue) MuSCs shows down-regulation of Piezo1 in dystrophic cells. n = 3 controls and n = 6 dystrophic animals (3 months old) for MuSC isolation. Results are shown as means ± SEM; statistical analysis was performed using unpaired Student’s t test with Welch’s correction, ** P < 0.01. ( C ) Reduced number of responsive cells and increased number of sensory cells in dystrophic muscles. ( D ) Increased protrusion length in all types of dystrophic MuSCs. ( E ) Representative images of dystrophic MuSCs show the complexity of the protrusions in these cells. Dystrophic cells are green (EGFP), and sarcomeres are marked by SHG in red. Scale bars, 10 μm. ( F ) Cells are significantly elongated in dystrophic compared to uninjured muscles. n = 3 to 4 mice (2 months old) were analyzed per condition, and N > 400 cells per mouse. Data in (C) to (E) were analyzed by two-way ANOVA, followed by Šídák’s multiple comparisons test. Data in (B) were analyzed by unpaired t test with Welch’s correction. Values are presented as means ± SEM. * P < 0.05, ** P < 0.01, and **** P < 0.0001.

Article Snippet: Primers were purchased from Applied Biosystems and included Piezo1-FAM (Mm012415449_m1) and GAPDH-VIC (4352339e).

Techniques: Muscles, Quantitative RT-PCR, Control, Isolation

Journal: Science Advances

Article Title: Piezo1 regulates the regenerative capacity of skeletal muscles via orchestration of stem cell morphological states

doi: 10.1126/sciadv.abn0485

Figure Lengend Snippet: ( A ) Experimental scheme for pharmacological activation of Piezo1 in dystrophic mice. Two-month-old male mdx/Pax7EGFP mice were injected with either DMSO or Yoda1 for five consecutive days per week for 2 weeks (d1 to d5 and d8 to d12), and their TA was imaged at d15. ( B ) Representative maximum intensity projections of mdx/Pax7EGFP treated with DMSO (left) and dystrophic (mdx/Pax7EGFP) muscle treated with Yoda1 (right) at 2 months old. Note the reduced complexity of protrusions in the Yoda1-treated compared to the DMSO-treated muscles. Dystrophic MuSCs are shown in green. Scale bars, 60 μm. ( C ) Shift toward more responsive cells in Yoda1-treated dystrophic muscles compared to DMSO-treated muscles. ( D ) Protrusion length was brought down in all types of dystrophic MuSCs treated with Yoda1. ( E ) Representative images of dystrophic MuSCs from muscles treated with Yoda1 show the diminished complexity of the protrusions in these cells. Dystrophic cells are green (EGFP), and sarcomeres are marked by SHG in red. Scale bars, 10 μm. ( F ) Cells with zero to two protrusions in dystrophic muscles treated with Yoda1 are less elongated, better resembling the MuSC shape of a physiological muscle. n = 4 to 5 mice (2 months old) were analyzed per condition, and N > 600 cells per mouse. Data in (C), (D), and (F) were analyzed by two-way ANOVA, followed by Šídák’s multiple comparisons test. Values are presented as means ± SEM. * P < 0.05, ** P < 0.01, *** P < 0.001, and **** P < 0.0001.

Article Snippet: Primers were purchased from Applied Biosystems and included Piezo1-FAM (Mm012415449_m1) and GAPDH-VIC (4352339e).

Techniques: Activation Assay, Injection, Muscles

Journal: BioMedical Engineering OnLine

Article Title: Effect of hip joint angle at seat-off on hip joint contact force during sit-to-stand movement: a computer simulation study

doi: 10.1186/s12938-018-0610-5

Figure Lengend Snippet: Musculoskeletal model. Eight muscles (iliopsoas, gluteus maximus, vastus, rectus femoris, hamstrings, tibialis anterior, soleus, and gastrocnemius) were attached to the right lower limb. Furthermore, the muscles of the left lower limb were assumed to perform the same activities as those of the right lower limb

Article Snippet: The moment arm lengths of the gluteus maximus, quadriceps (i.e., patellar tendon), and other muscles were obtained using the Hip Musculoskeletal Model (only flexion and extension components) on OpenSim, the function reported by Herzog et al. [ ], and the Full Body Model [ , ] (only flexion and extension components) on OpenSim, respectively.

Techniques: Muscles