Volume 23 · Issue 07 · 2025

The accumulation of deoxyribonucleic acid (DNA) oxidative damage mediated by reactive oxygen species (ROS) is closely associated with liver diseases. 8-Oxoguanine (8-OxoG), a prevalent DNA oxidation product, plays a significant role in liver disease progression. The base excision repair (BER) pathway, comprising over 30 proteins including 8-OxoG DNA glycosylase1 (OGG1), MutY homolog (MUTYH), and MutT homolog protein 1 (MTH1), is responsible for the clearance and mismatch repair of 8-OxoG. Abnormally high levels of 8-OxoG and dysregulated expression and function of 8-OxoG repair enzymes contribute to the onset and development of liver diseases. Consequently, targeting the 8-OxoG production and repair system with agonists or inhibitors may offer a promising approach to liver disease treatment. This review summarizes the impact of 8-OxoG accumulation and dysregulated repair enzymes on various liver diseases, including viral liver disease, alcoholic liver disease (ALD), metabolic dysfunction-associated steatotic liver disease (MASLD), cholestatic liver disease (CLD), liver fibrosis, cirrhosis, and liver cancer. Additionally, we review natural constituents as potential therapeutic agents that regulate 8-OxoG production, repair enzymes, and repair system-related signal pathways in oxidative damage-induced liver diseases.

Polycyclic polyprenylated acylphloroglucinols (PPAPs) represent a distinct subclass of specialized metabolites predominantly found in the plant kingdom, particularly within the Guttiferae (Clusiaceae) family. These compounds exhibit remarkable structural diversity and a wide range of biological activities. Seco- and nor-PPAPs, two unique variants of PPAPs with diverse skeletal structures, have been extensively investigated. As of June 2023, 200 compounds have been isolated from four genera, with Hypericum being the primary source. Notably, 115 of these compounds were identified in the past four years, indicating a significant increase in research activity. Seco- and nor-PPAPs can be categorized into six main subgroups based on the original PPAP scaffolds. Biological studies have revealed their potential in various therapeutic applications, including anti-cancer, anti-inflammatory, hepatoprotective, anti-Alzheimer’s disease (anti-AD), multidrug resistance (MDR) reversal, anti-depressant, neuroprotective, and immunosuppressive effects. This review provides a comprehensive overview of the occurrence, structures, and bioactivities of natural seco- and nor-PPAPs, offering valuable insights for the further development of PPAPs.

Our previous research demonstrated that the Wenxia Changfu Formula (WCF), as a neoadjuvant therapy, inhibits M2 macrophage infiltration in the tumor microenvironment and prevents lung cancer metastasis. Given tumor-associated macrophages (TAMs) in epithelial-mesenchymal transition (EMT), this study investigated whether WCF impedes lung cancer metastasis by attenuating TAM-induced EMT in non-small cell lung cancer (NSCLC) cells. Utilizing a co-culture model treated with or without WCF, we observed that WCF downregulated cluster of differentiation 163 (CD163) expression in macrophages, reduced CCL18 levels in the conditioned medium, and inhibited the growth, invasion, and EMT of NSCLC cells induced by macrophage co-culture. Manipulation of CCL18 levels and Src overexpression in NSCLC cells revealed that WCF’s effects are mediated through CCL18 and Src signaling. In vivo, WCF inhibited recombinant CCL18 (rCCL18)-induced tumor metastasis in nude mice by blocking Src signaling. These findings indicate that WCF inhibits NSCLC metastasis by impeding TAM-induced EMT via antagonistic modulation of CCL18, providing evidence for its potential development and clinical application in NSCLC patients.

Ulcerative colitis (UC) is a chronic inflammatory disorder with a complex etiology, characterized by intestinal inflammation and barrier dysfunction. Platycodon grandiflorus polysaccharides (PGP), the primary component of Platycodon grandiflorus, and hesperidin (Hesp), a prominent active component in Citrus aurantium L. (CAL), have both demonstrated anti-inflammatory properties. This study aims to elucidate the underlying mechanism of the synergistic effect of PGP combined with Hesp on UC, focusing on the coordinated interaction between the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) and Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathways. A mouse model of UC induced by dextran sulfate sodium (DSS) and a cell model using lipopolysaccharide (LPS)-induced RAW264.7/IEC6 cells were employed to investigate the in vitro and in vivo anti-inflammatory effects of PGP combined with Hesp on UC and its potential mechanism of action. The results indicated that compared to the effects of either drug alone, the combination of PGP and Hesp significantly modulated inflammatory factor levels, inhibited oxidative stress, regulated colonic mucosal immunity, suppressed apoptosis, and restored intestinal barrier function in vitro and in vivo. Further in vitro studies revealed that PGP significantly inhibited the PI3K/AKT signaling pathway, while Hesp significantly inhibited the JAK2/STAT3 signaling pathway. The use of inhibitors and activators targeting both pathways validated the synergistic effects of PGP combined with Hesp on the PI3K/AKT and JAK2/STAT3 signaling pathways. These findings suggest that PGP combined with Hesp exhibits a synergistic effect on DSS-induced colitis, potentially mediated through the phosphatase and tensin homolog (PTEN)/PI3K/AKT and interleukin-6 (IL-6)/JAK2/STAT3 signaling pathways.

Obesity and metabolic dysfunction-associated steatotic liver disease (MASLD) are linked to numerous chronic conditions, including cardiovascular disease, atherosclerosis, chronic kidney disease, and type II diabetes. Previous research identified the natural flavonoid diosmin, derived from Chrysanthemum morifolium, as a regulator of glucose metabolism. However, its effects on lipid metabolism and underlying mechanisms remained unexplored. The AMP-activated protein kinase (AMPK) pathway serves a critical function in glucose and lipid metabolism. The relationship between diosmin and the AMPK pathway has not been previously documented. This investigation examined diosmin's capacity to reduce lipid content through AMPK pathway activation in hepatoblastoma cell line G2 (HepG2) and 3T3-L1 cells. The study revealed that diosmin inhibits lipogenesis, indicating its potential as an anti-obesity agent in obese mice. Moreover, diosmin demonstrated effective MASLD alleviation in vivo. These findings suggest that diosmin may represent a promising therapeutic candidate for treating obesity and MASLD.

Five previously undescribed diterpenoids, named succipenoids D‒H (1‒5), along with four undescribed lignans, named succignans A‒D (6‒9), were isolated from the dichloromethane extract of Chinese medicinal succinum. Compounds 1‒5 were characterized as nor-abietane diterpenoids, while compounds 6‒9 were identified as lignans polymerized from two groups of phenylpropanoid units. The structures of these novel compounds, including their absolute configurations, were determined through spectroscopic and computational methods. Biological assessments of renal fibrosis demonstrated that compounds 6 and 7 effectively reduce the expression of proteins associated with renal fibrosis, including α-smooth muscle actin (α-SMA), collagen I, and fibronectin in transforming growth factor-β1 (TGF-β1) induced normal rat kidney proximal tubular epithelial cells (NRK-52e).