Abstract：
The aim of the present study was to compare the therapeutic effects of activated platelet-rich plasma (PRP) prepared from elderly individuals and young adults to treat pressure ulcers (PUs), and to accumulate a theoretical basis for allogeneic PRP treatment of PUs in elderly patients.
Whole blood was extracted from elderly individuals aged >65 y and young adult volunteers for PRP preparation, and platelet concentrations in whole blood and PRP were compared. Growth factors released from activated PRP were assayed using the enzyme-linked immunosorbent assay. C57BL/6 mice were divided into three groups: the control saline, elderly-PRP (Group A), and young adult-PRP (Group B). Ischemia-reperfusion injury-induced PUs were established on the backs of mice. PUs were photographed on days 0, 5, and 10 to assess their sizes. Specimens were collected on day 10 and subjected to hematoxylin and eosin and Masson\'s staining. Immunohistochemical staining for CD31 was conducted to evaluate vascular formation, and cell invasion was assessed using a Transwell assay. The action of PRP on transforming growth factor-beta (TGF-β)-dependent fibroblast activity and epithelial-mesenchymal transition was analyzed using immunofluorescence and Western blotting in vitro.
The platelet concentrations in whole blood and PRP of young adults were significantly higher than that in elderly individuals. The two PRP treatment groups had similar platelet enrichment coefficients of PRP. After activation, PRP from young adults produced significantly higher levels of platelet-derived growth factor, TGF-β, and vascular endothelial growth factor than PRP from elderly individuals (P < 0.05). The concentrations of platelet-derived growth factor, TGF-β, and vascular endothelial growth factor were positively correlated with the platelet concentrations in whole blood and PRP. The effects of PRP in regulating the expressions of TGF-β, α-smooth muscle actin, vimentin, and E-cadherin were observed in vivo and in vitro. The two PRP treatment groups exhibited better wound healing than the control group, as evidenced by more re-epithelialization, higher collagen content, skin fibrosis, and more blood vessel formation over time. Group B exhibited better wound healing than Group A (P < 0.05).
PRP exhibits potent wound healing ability in PU therapy, and PRP from young adults is seemingly superior to that from elderly individuals because of a higher concentration of platelets and increased production of growth factors.
Whole blood was extracted from elderly individuals aged >65 y and young adult volunteers for PRP preparation, and platelet concentrations in whole blood and PRP were compared. Growth factors released from activated PRP were assayed using the enzyme-linked immunosorbent assay. C57BL/6 mice were divided into three groups: the control saline, elderly-PRP (Group A), and young adult-PRP (Group B). Ischemia-reperfusion injury-induced PUs were established on the backs of mice. PUs were photographed on days 0, 5, and 10 to assess their sizes. Specimens were collected on day 10 and subjected to hematoxylin and eosin and Masson\'s staining. Immunohistochemical staining for CD31 was conducted to evaluate vascular formation, and cell invasion was assessed using a Transwell assay. The action of PRP on transforming growth factor-beta (TGF-β)-dependent fibroblast activity and epithelial-mesenchymal transition was analyzed using immunofluorescence and Western blotting in vitro.
The platelet concentrations in whole blood and PRP of young adults were significantly higher than that in elderly individuals. The two PRP treatment groups had similar platelet enrichment coefficients of PRP. After activation, PRP from young adults produced significantly higher levels of platelet-derived growth factor, TGF-β, and vascular endothelial growth factor than PRP from elderly individuals (P < 0.05). The concentrations of platelet-derived growth factor, TGF-β, and vascular endothelial growth factor were positively correlated with the platelet concentrations in whole blood and PRP. The effects of PRP in regulating the expressions of TGF-β, α-smooth muscle actin, vimentin, and E-cadherin were observed in vivo and in vitro. The two PRP treatment groups exhibited better wound healing than the control group, as evidenced by more re-epithelialization, higher collagen content, skin fibrosis, and more blood vessel formation over time. Group B exhibited better wound healing than Group A (P < 0.05).
PRP exhibits potent wound healing ability in PU therapy, and PRP from young adults is seemingly superior to that from elderly individuals because of a higher concentration of platelets and increased production of growth factors.
摘要：
目的：本研究的目的是比较老年人和年轻人制备的活化富血小板血浆（PRP）治疗压疮（PU）的疗效，为同种异体PRP治疗老年患者PUs积累理论依据。
方法：从年龄>65岁的老年人和年轻的成年志愿者中提取全血，用于制备PRP，比较全血和PRP中的血小板浓度。使用酶联免疫吸附测定法测定从活化的PRP释放的生长因子。将C57BL/6小鼠分为三组：对照盐水，老年PRP（A组），和年轻成人PRP（B组）。在小鼠背部建立缺血再灌注损伤诱导的PU。在第0、5和10天拍摄PU以评估其大小。在第10天收集样本并进行苏木精和曙红和Masson's染色。进行CD31的免疫组织化学染色以评估血管形成，并且使用Transwell测定法评估细胞侵袭。使用免疫荧光和Western印迹在体外分析了PRP对转化生长因子-β（TGF-β）依赖性成纤维细胞活性和上皮-间质转化的作用。
结果：青壮年全血和PRP中的血小板浓度明显高于老年人。两个PRP治疗组的血小板富集系数与PRP相似。激活后,来自年轻人的PRP产生明显更高水平的血小板衍生生长因子，TGF-β,血管内皮生长因子高于PRP(P<0.05)。血小板衍生生长因子的浓度，TGF-β,血管内皮生长因子与全血和PRP中血小板浓度呈正相关。PRP对TGF-β表达的调控作用,α-平滑肌肌动蛋白，波形蛋白,在体内和体外观察到E-cadherin。两个PRP治疗组均表现出比对照组更好的伤口愈合。更多的再上皮化证明了这一点，胶原蛋白含量较高，皮肤纤维化,随着时间的推移，更多的血管形成。B组创面愈合情况优于A组(P<0.05)。
结论：PRP在PU治疗中表现出有效的伤口愈合能力，由于血小板浓度较高和生长因子的产生增加，年轻人的PRP似乎优于老年人。
方法：从年龄>65岁的老年人和年轻的成年志愿者中提取全血，用于制备PRP，比较全血和PRP中的血小板浓度。使用酶联免疫吸附测定法测定从活化的PRP释放的生长因子。将C57BL/6小鼠分为三组：对照盐水，老年PRP（A组），和年轻成人PRP（B组）。在小鼠背部建立缺血再灌注损伤诱导的PU。在第0、5和10天拍摄PU以评估其大小。在第10天收集样本并进行苏木精和曙红和Masson's染色。进行CD31的免疫组织化学染色以评估血管形成，并且使用Transwell测定法评估细胞侵袭。使用免疫荧光和Western印迹在体外分析了PRP对转化生长因子-β（TGF-β）依赖性成纤维细胞活性和上皮-间质转化的作用。
结果：青壮年全血和PRP中的血小板浓度明显高于老年人。两个PRP治疗组的血小板富集系数与PRP相似。激活后,来自年轻人的PRP产生明显更高水平的血小板衍生生长因子，TGF-β,血管内皮生长因子高于PRP(P<0.05)。血小板衍生生长因子的浓度，TGF-β,血管内皮生长因子与全血和PRP中血小板浓度呈正相关。PRP对TGF-β表达的调控作用,α-平滑肌肌动蛋白，波形蛋白,在体内和体外观察到E-cadherin。两个PRP治疗组均表现出比对照组更好的伤口愈合。更多的再上皮化证明了这一点，胶原蛋白含量较高，皮肤纤维化,随着时间的推移，更多的血管形成。B组创面愈合情况优于A组(P<0.05)。
结论：PRP在PU治疗中表现出有效的伤口愈合能力，由于血小板浓度较高和生长因子的产生增加，年轻人的PRP似乎优于老年人。
