ABSTRACT
Liver is the central hub regulating energy metabolism during feeding-fasting transition. Evidence suggests that fasting and refeeding induce dynamic changes in liver size, but the underlying mechanisms remain unclear. Yes-associated protein (YAP) is a key regulator of organ size. This study aims to explore the role of YAP in fasting- and refeeding-induced changes in liver size. Here, fasting significantly reduced liver size, which was recovered to the normal level after refeeding. Moreover, hepatocyte size was decreased and hepatocyte proliferation was inhibited after fasting. Conversely, refeeding promoted hepatocyte enlargement and proliferation compared to fasted state. Mechanistically, fasting or refeeding regulated the expression of YAP and its downstream targets, as well as the proliferation-related protein cyclin D1 (CCND1). Furthermore, fasting significantly reduced the liver size in AAV-control mice, which was mitigated in AAV Yap (5SA) mice. Yap overexpression also prevented the effect of fasting on hepatocyte size and proliferation. Besides, the recovery of liver size after refeeding was delayed in AAV Yap shRNA mice. Yap knockdown attenuated refeeding-induced hepatocyte enlargement and proliferation. In summary, this study demonstrated that YAP plays an important role in dynamic changes of liver size during fasting-refeeding transition, which provides new evidence for YAP in regulating liver size under energy stress.
ABSTRACT
【Objective】 To investigate the significance of granulocyte macrophage colony-stimulating factor (GM-CSF), nerve growth factor (NGF) and interleukin-17 (IL-17) in the prostate tissue of rats with experimental autoimmune prostatitis(EAP). 【Methods】 EAP rat models were established and divided into control group, EAP group, anti-GM-CSF group (blocking control group) and anti-GM-CSFEAP group (blocking EAP group). Pain behaviors were tested. The pathological changes were observed with HE staining. The mRNA and protein expressions of GM-CSF, NGF and IL-17 were detected with RT-PCR and Western blot. 【Results】 Pain test showed the anti-GM-CSF group had less chronic pelvic pain than the EAP group. HE staining showed the anti-GM-CSF group had less tissue inflammatory response. The EAP inflammation score was higher in the control group than in the anti-GM-CSF group. Immunohistochemistry showed GM-CSF was positive in the EAP group (mainly in the nucleus). RT-PCR and Western blot results showed the mRNA and protein expressions of IL-17 and NGF significantly decreased 50 days after EAP in the anti-GM-CSF group. 【Conclusion】 Increased expressions of GM-CSF, NGF and IL-17 in prostate tissue of EAP rats may be important inflammatory mediators of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS);decreased expressions of NGF and IL-17 after resistance against GM-CSF indicate that GM-CSF may be a potential therapeutic target for CP/CPPS.
ABSTRACT
The constitutive androstane receptor (CAR, NR3I1) belongs to nuclear receptor superfamily. It was reported that CAR agonist TCPOBOP induces hepatomegaly but the underlying mechanism remains largely unknown. Yes-associated protein (YAP) is a potent regulator of organ size. The aim of this study is to explore the role of YAP in CAR activation-induced hepatomegaly and liver regeneration. TCPOBOP-induced CAR activation on hepatomegaly and liver regeneration was evaluated in wild-type (WT) mice, liver-specific YAP-deficient mice, and partial hepatectomy (PHx) mice. The results demonstrate that TCPOBOP can increase the liver-to-body weight ratio in wild-type mice and PHx mice. Hepatocytes enlargement around central vein (CV) area was observed, meanwhile hepatocytes proliferation was promoted as evidenced by the increased number of KI67