Hepatic stellate cells (HSCs) are the primary fibrogenic cells in the liver, and their activation plays a crucial role in the development and progression of hepatic fibrosis. Here, we report that retinoid X receptor-alpha (RXRα), a unique member of the nuclear receptor superfamily, is a key modulator of HSC activation and liver fibrosis. RXRα exerts its effects by modulating calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ)-mediated activation of AMP-activated protein kinase-alpha (AMPKα). In addition, we demonstrate that K-80003, which binds RXRα by a unique mechanism, effectively suppresses HSC activation, proliferation, and migration, thereby inhibiting liver fibrosis in the CCl₄ and amylin liver NASH (AMLN) diet animal models. The effect is mediated by AMPKα activation, promoting mitophagy in HSCs. Mechanistically, K-80003 activates AMPKα by inducing RXRα to form condensates with CaMKKβ and AMPKα via a two-phase process. The formation of RXRα condensates is driven by its N-terminal intrinsic disorder region and requires phosphorylation by CaMKKβ. Our results reveal a crucial role of RXRα in liver fibrosis regulation through modulating mitochondrial activities in HSCs. Furthermore, they suggest that K-80003 and related RXRα modulators hold promise as therapeutic agents for fibrosis-related diseases.

OBJECTIVETo observe the clinical efficacy of Safflower Injection (Al) in treating and preventing the vascular crisis after free flap transplantation.

METHODSSixty patients undergoing free flap transplantation were randomly assigned to the treatment group and control group according to the visiting sequence, thirty in each. Free flap transplantation was performed on all patients, and medication was given 0. 5 h before flap vascular anastomosis, 1-7 days after surgery. Twenty mL Al was intravenously dripped to patients in the treatment group after adding in 250 mL 5% glucose injection, while Dextran-40 was intravenously dripped to patients in the control group. The medication was conducted once per day. The hemorheology and four indices of blood coagulation [prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (APTT), fibrinogen (FIB)] were compared between the two groups before operation (TO), during operation (T1), 24 h after operation (T2), three days after operation (T3), and seven days after operation (T4). Meanwhile, flaps were observed and adverse reaction recorded. The clinical efficacy and safety were compared.

RESULTSBetter result was obtained in the treatment group when compared their clinical efficacy (86. 67% vs 60. 00%, P<0.05). The whole blood high and low viscosity, plasma viscosity, red blood cell (RBC) volume, RBC aggregation index all decreased, and RBC deformed index increased in the two groups at T4, showing statistical difference when compared with those at T3 (P<0.05, P<0.01). There was no statistical significance in the four indices of blood coagulation when compared with any time point in the same group (P>0.05). There was no statistical significance in hemorheology and the four indices of blood coagulation between the two groups at the same time point (P>0.05). The adverse reaction rate in the treatment group was lower than that in the control group, showing statistical difference (13.33% vs 30.00%, P<0.05).

CONCLUSIONSAI could effectively prevent and treat the vascular crisis after free flap transplantation. It had less adverse reaction and good safety. It was better than Dextran-40. It was a safe and effective drug to prevent the vascular crisis.

Adult ; Carthamus tinctorius ; Female ; Free Tissue Flaps ; adverse effects ; Humans ; Injections ; Male ; Middle Aged ; Phytotherapy ; Skin Transplantation ; adverse effects ; Vascular Diseases ; etiology ; prevention & control ; Young Adult