ABSTRACT
Phosphatidylserine (PS) is distributed asymmetrically in the plasma membrane of eukaryotic cells. Phosphatidylserine flippase (P4-ATPase) transports PS from the outer leaflet of the lipid bilayer to the inner leaflet of the membrane to maintain PS asymmetry. The ß subunit TMEM30A is indispensable for transport and proper function of P4-ATPase. Previous studies have shown that the ATP11A and TMEM30A complex is the molecular switch for myotube formation. However, the role of Tmem30a in skeletal muscle regeneration remains elusive. In the current study, Tmem30a was highly expressed in the tibialis anterior (TA) muscles of dystrophin-null ( mdx) mice and BaCl 2-induced muscle injury model mice. We generated a satellite cell (SC)-specific Tmem30a conditional knockout (cKO) mouse model to investigate the role of Tmem30a in skeletal muscle regeneration. The regenerative ability of cKO mice was evaluated by analyzing the number and diameter of regenerated SCs after the TA muscles were injured by BaCl 2-injection. Compared to the control mice, the cKO mice showed decreased Pax7 + and MYH3 + SCs, indicating diminished SC proliferation, and decreased expression of muscular regulatory factors (MYOD and MYOG), suggesting impaired myoblast proliferation in skeletal muscle regeneration. Taken together, these results demonstrate the essential role of Tmem30a in skeletal muscle regeneration.
Subject(s)
Membrane Proteins/metabolism , Muscle, Skeletal/physiology , Regeneration/physiology , Satellite Cells, Skeletal Muscle/metabolism , Animals , Cell Proliferation , Dystrophin/genetics , Dystrophin/metabolism , Estrogen Antagonists/toxicity , Gene Expression Regulation/physiology , Genotype , Membrane Proteins/genetics , Mice , Mice, Inbred mdx , Mice, Knockout , Muscle, Skeletal/drug effects , MyoD Protein/genetics , MyoD Protein/metabolism , Myogenin/genetics , Myogenin/metabolism , Myosin Heavy Chains/genetics , Myosin Heavy Chains/metabolism , PAX7 Transcription Factor/genetics , PAX7 Transcription Factor/metabolism , Regeneration/genetics , Tamoxifen/toxicityABSTRACT
<p><b>OBJECTIVE</b>To explore the memory quotient and hormone level in women with perimenopausal syndrome and healthy women in perimenopausal period, and the effect of estrogen and Chinese nourishing Kidney herbs (CNKH) on memory.</p><p><b>METHODS</b>Fifty-six women of perimenopausal syndrome were treated with estrogen (n = 24) and CNKH (n = 32) respectively. The changes of memory and estrogen level before and after treatment were determined and compared with those in healthy women.</p><p><b>RESULTS</b>The memory quotient (MQ) and estrogen level increased and follicule-stimulating hormone (FSH) level decreased significantly after treatment in both groups (P < 0.01), these parameters approached to those in healthy women. The difference of therapeutic effect between the two treated group was insignificant (P > 0.05).</p><p><b>CONCLUSION</b>The decrease of memory is related to the lowering of estrogen level, CNKH could improve the brain function and enhance memory.</p>
