Date Published: August 19, 2019
Publisher: Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia
Author(s): Gyeong Seok Lee, Hyeon Gung Yang, Ji Hun Kim, Young Mo Ahn, Man Deuk Han, Wan Jong Kim.
To investigate the effects of pine needle extract (PNE) on the expression of proliferating cell nuclear antigen (PCNA) and Ki-67 during liver regeneration induced by 70% partial hepatectomy (PH) in rat.
Forty-eight male rats (SD, 7 weeks) had surgery (70% PH). They were randomly divided into two groups. PH + PNE group was only provided PNE diluted in water (10%) for drinking and PH group was provided water from 5 days before surgery to the time of sacrifice. PNE was made by pressing and filtering. Animals were sacrificed at 12h, 24h, 36h, 60h, 84h, 168h after PH, respectively. The expressions of PCNA and Ki-67 were determined as proliferation indices.
Immunohistochemistry turned out to increase the expression of PCNA and Ki-67. PCNA expression of PH+PNE group increased up to twice of that of PH group. Western blot also seemed to increase the PCNA expression. These results indicated the promotion of cell proliferation in liver tissue and hepatic regeneration.
Pine needle extract stimulates the expression of some mitotic proteins during liver regeneration induced by 70% PH in rats. It suggests that administration of pine needle extract could accelerate the liver regeneration after partial hepatectomy.
The liver plays a crucial role in metabolism that involves blood glucose regulation, protein synthesis, bile production, detoxification, and urea production. It also maintains metabolic homeostasis and harmony in the body, and acts in cooperation with many organs. In rats, median and left lateral lobes of liver comprise about 70% of total liver volume. The main type of hepatic cell is hepatocyte. The liver has the unique ability to regenerate after injury, and the term ‘liver regeneration’ is generally used in scholarly articles. It has been more precisely termed ‘compensatory hyperplasia’ of liver tissue 1 – 3 . This phenomenon involves rapid growth of the liver tissue after injury induced tissue loss or damage.
In the present study, we investigated the effects of pine needle extract (PNE) on liver regeneration induced by 70% partial hepatectomy (PH) in a rat model. We focused on proliferation of hepatocytes and expression of proliferating cell nuclear antigen (PCNA) and Ki-67 protein. During regeneration, quiescent hepatocytes undergo replication and then return to a non-proliferative state. This process is regulated by certain growth factors, including HGF (hepatocyte growth factor), EGF (epidermal growth factor), TNF-α (tumor necrosis factor alpha), VEGF (vascular endothelial growth factor), TGF-β (transforming growth factor beta) and other cytokines 22 – 25 .
Fermented pine ( Pinus densiflora ) needle extract stimulated some mitotic proteins as proliferating cell nuclear antigen and proliferation of hepatic cells during liver regeneration induced by 70% partial hepatectomy in rats.