The Effect Of Gynostemma Pentaphyllum On The Age-Associated Change Of Guangxi Sanhuang Chickens Thymus

The effect of Gynostemma pentaphyllum was studied on thymus with the weight of thymus, thymus index, the area ratio between cortex and medulla, the number and area of thymic corpuscle, the number of mast cells, the number and MOD of Ghrelin positive cells under optical microscope from 1 day to 150 day by adding 0.5% Gynostemma pentaphyllum powder in the feed of Guangxi Sanhuang Chickens and using HE, modified toluidine blue and immunohistochemical staining methods in this study. The research was to provide some morphological basis for the further study that Gynostemma pentaphyllum can enhance immunity, investigate the effect of Gynostemma pentaphyllum on thymus organization structure and promote the development and utilization of Gynostemma pentaphyllum.Morphological study showed that:The Guangxi Sanhuang Chickens thymus was wrapped with a layer of capsule, penetrating into thymus which was divided into multiple sizes of thymic lobule. The periphery of thymic lobule was cortical stained deeper than medulla which was in the central of thymic lobule. There were three types of thymus corpuscle in the medulla, namely the single reticular cell, the reticular cells in a concentric arrangement and the mass thymic corpuscle. The multi-shaped and sized mast cells (MTB) whose cytoplasm were dyed mauve and nucleus were blue, distributed in cluster or scattered. The mast cells were mainly distributed in the medulla of thymus, especially around the thymus corpuscle and blood vessels, or scattered among the thymocyte cells. However, there were fewer mast cells in the cortex, blood vessels and intralobular interstitial. The majority of Ghrelin positive cells (SP) were macrophages and epithelial reticular cells, mainly distributed in the medulla and crtico-medullary junction. Some thymic corpuscle also had positive reaction. Positive substance was located in the cytoplasm.Statistical results showed that:1、With the increase of age, the weight of thymus increased gradually. The thymus index increased first and began to decrease after reaching the maximum. Although no significant difference (P>0.05), Gynostemma pentaphyllum improved the thymus weight and thymus index to a certain extent.2、The area ratio between cortex and medulla decreased gradually, and a significant difference among different ages. At 120-day-old, the area ratio between cortex and medulla of experimental group was greater than control group (P<0.05)3、After the thymus corpuscle number of control group and experimental group respectively achieving the biggest at 56 day and 90 day, both of them showed a wavy decline. At 28 and 120-day-old, the thymus corpuscle number of experimental group was more than control group (P<0.05), and the difference was extremely significant at 90-day-old (P<0.01). However, at 56-day-old, the thymus corpuscle number of control group was more than experimental group (P<0.05). The thymic corpuscle area of control group and experimental group increased gradually before 120-day-old, then began to decline. However, there was no obvious difference between control group and experimental group, indicating that there was no significant effect of Gynostemma pentaphyllum on thymic corpuscle area.4、There was a significant difference among different ages, generally, the number of mast cells in the thymus decreased with aging, suggesting the decrease of mast cells may be related to the change of sex hormone and T cells. At 120-day-old, the mast cells number of experimental group was greater than the control group, extremely significant difference (P<0.01), and the difference was significant at 150-day-old (P<0.05). Although the difference was small (P>0.05), the mast cells number of experimental group was more than control groupat 90 day. Conclusion, Gynostemma pentaphyllum could enhance the immune function of aging animals.5、The number of Ghrelin positive cells increased gradually at first, and began to decrease after reaching the most at 120-day-old, suggesting the decrease of Ghrelin may contribute to thymic atrophy. The Ghrelin positive cells number of experimental group was more than control group at 90 and ] 50-day-old (P<0.05). The change of Ghrelin positive cells MOD was wavy, and a significant difference among different ages. At 90 and 150-day-old, the MOD of experimental group was greater than the control group (P<0.05). At 14-day-old, the MOD of experimental group was greater than the control group, however, the control group was greater than experimental group at 56-day-old, no obvious difference (P>0.05). Conclusion, Gynostemma pentaphyllum could increse Ghrelin levels in the aging thymus, helping delay the thymic atrophy.6、The above research results showed that 0.5% Gynostemma pentaphyllum powder added in the feed could promote the early development of the thymus, improve aging thymus tissue structure and the immune function of the thymus.