Shiseido Global Innovation Center, 1-2-11Nishi-ku Yokohama, Takashima, 220-1100, Japan.
Angiogenesis. 2020 May;23(2):79-82. doi: 10.1007/s10456-020-09705-1. Epub 2020 Jan 28.
Aging is associated with a progressive decline in muscle mass, strength, and quality. We have previously demonstrated the important role of the blood vasculature system in ultraviolet (UV) light-induced changes in skin and its molecular mechanisms. Whereas recent findings revealed structural alterations of the cutaneous vasculature in aged and photoaged human skin, structural changes of blood vessels in skeletal muscles with age have remained unclear. Although, facial skeletal muscles could be involved in skin-aging, here, we show-for the first time-that, in the lateral great muscle, the cross-sectional muscle fiber area and vessels size were decreased in older skin compared with that in younger skin. In the orbicularis oculi muscle, no significant interaction between age and the muscle fiber area was observed. However, a significantly decreased ratio of muscle area was indicated in older skin compared with that in younger skin. Interestingly, the pericyte-covered vessels ratio was decreased in older skin. Therefore, we found that the skeletal muscle capillary destabilizes with age. In summary, we revealed that the lateral great muscle and the orbicularis oculi muscle fibers become thinner with age due to the destabilization of skeletal muscle capillaries. Therapeutic targeting of muscle capillaries might affect the decline of skeletal muscles with age and could potentially regulate muscle/skin-aging.
衰老是与肌肉质量、力量和功能的逐渐下降相关联的。我们之前已经证明了血液脉管系统在紫外线（UV）光诱导的皮肤变化及其分子机制中的重要作用。虽然最近的研究结果揭示了老化和光老化的人类皮肤中皮肤脉管系统的结构改变，但年龄相关的骨骼肌血管的结构变化仍不清楚。尽管面部骨骼肌肉可能参与皮肤衰老，但在这里，我们首次表明，与年轻皮肤相比，外侧大肌肉中的横截面肌纤维面积和血管大小在老年皮肤中减少。在眼轮匝肌中，年龄和肌纤维面积之间没有观察到显著的相互作用。然而，与年轻皮肤相比，老年皮肤中肌肉面积的比例明显减少。有趣的是，老年皮肤中覆盖周细胞的血管比例降低。因此，我们发现骨骼肌毛细血管随着年龄的增长而不稳定。总之，我们揭示了由于骨骼肌毛细血管的不稳定，外侧大肌肉和眼轮匝肌纤维随着年龄的增长而变细。针对肌肉毛细血管的治疗性靶向可能会影响与年龄相关的骨骼肌衰退，并可能潜在地调节肌肉/皮肤衰老。
