Trolline Ameliorates Liver Fibrosis by Inhibiting the NF-κB Pathway, Promoting HSC Apoptosis and Suppressing Autophagy

Abstract

Background/Aims: Previous studies have shown that trolline possesses various forms of pharmacological activity, including antibacterial and antiviral potency. The present paper addressed the putative hepatoprotective effects of trolline. Methods: Rats received 2 ml/kg CCl₄ (mixed 1: 1 in peanut oil) intragastrically twice a week for 8 weeks to induce hepatic fibrosis. The animals were then treated with trolline for additional 4 weeks. Liver pathology and collagen accumulation were observed by hematoxylin-eosin and Masson’s trichrome staining, respectively. Serum transaminase activity and collagen-related indicator level were determined by commercially available kits. NF-κB pathway activation was also examined. Moreover, the effects of trolline on hepatic stellate cell (HSC-T6) apoptosis, mitochondrial membrane potential (MMP), and autophagy were assessed. Results: Trolline significantly alleviated CCl₄-induced liver injury and notably reduced the accumulation of collagen in liver tissues. Trolline treatment also markedly decreased inflammatory cytokines levels by inhibiting the NF-κB pathway. Trolline strongly inhibited HSC-T6 activation and notably induced cell apoptosis by modulating the Bax/Bcl-2 ratio, caspase activity, and MMP. Moreover, trolline significantly inhibited HSC-T6 autophagy, as evidenced by the decrease in the formation of autophagic vacuoles and the number of autophagosomes, by regulating the expression levles of LC3, Beclin-1, P62, Atg 5 and 7. Conclusion: Our study demonstrates that trolline ameliorates liver fibrosis, possibly by inhibiting the NF-κB pathway, promoting HSCs apoptosis and suppressing autophagy.

Dual TBK1/IKKɛ inhibitor amlexanox attenuates the severity of hepatotoxin‐induced liver fibrosis and biliary fibrosis in mice

“…42 Furthermore, recent studies have shown that NF-κB protects activated HSCs against TNFα-induced apoptosis, 43,44 and inhibition of NF-κB led to the promotion of HSC apoptosis, resulting in reduced severity of liver fibrosis. 45 Also, several studies have demonstrated that the apoptosis of activated HSCs is mechanistically implicated in the progression or resolution of liver fibrosis. 46,47 In line with these findings, treatment of amlexanox significantly increased the protein level of Bax (pro-apoptosis protein), with a concomitant decrease of protein level of Bcl2 (anti-apoptosis protein) in TGFβ-treated LX-2 cells and activated primary HSCs ( Figure S6A,B).…”

The Role of Autophagy and NLRP3 Inflammasome in Liver Fibrosis

“…In the process of liver fibrosis, autophagy works as a double-edged sword. On the one hand, the upregulated autophagy can activate HSCs, promoting the development of fibrosis; on the other hand, excessive autophagy may inhibit the development of fibrosis [8,9].…”

Methyl Helicterate Inhibits Hepatic Stellate Cell Activation Through Modulation of Apoptosis and Autophagy

“…Cell culture and treatment HSC-T6 cells were cultured in Dulbecco's modified eagle medium (DMEM) [10]. Cells were treated with equal amount of culture medium (normal control) or MH (3,6, and 12 μmol/l) in the absence or presence of various agents, including E64d (10 μg/ml, Cayman Chemical), Pep A (10 μg/ml, Sigma), 3-Methyl adenine (3-MA; 5 mmol/l, Sigma), Rapamycin (Rap; 10 nmol/l, Sigma), LY294002 (25 μmol/l, ALEXIS Biochemicals), and SP600125 (10 μmol/l, Cayman Chemical).…”

“…Transmission electron microscopy Cells were serum-starved for 12 h and treated with MH as described above for 24 h for morphological examination using transmission electron microscopy, as previously described [10].…”

“…The cells were next washed 4 times with PBS and observed under a fluorescence microscope at excitation wavelength of 380 nm and emission wavelength of 525 nm as previously described [10].…”