Enoxaparin attenuates pyrrolizidine alkaloids-induced hepatic sinusoidal obstruction syndrome by inhibiting oncostatin M expression

Histological evaluation of pyrrolizidine alkaloid-induced hepatic sinusoidal obstruction syndrome: Correlation with Drum Tower Severity Scoring

BACKGROUND

Hepatic sinusoidal obstruction syndrome induced by pyrrolizidine alkaloids (PA-HSOS) is a complication of drug-induced liver damage. Few studies have examined the relationship between pathological changes and clinical circumstances in PA-HSOS. The Drum Tower Severity Scoring System (DTSS) was developed using prognostic indicators from clinical treatment outcomes. We hypothesized that the severity of pathological damage is consistent with DTSS.

AIMS

We aimed to improve our understanding and assessment of vascular liver injury disease histopathology by studying larger sample sizes of human histopathological samples. We also wanted to confirm the link between histopathological findings and DTSS.

METHODS

The study included 62 patients with PA-HSOS who underwent transjugular liver biopsy. Their hepatic pathological tissues were evaluated. Analyses of linear regression and Spearman's correlation were employed to examine the relationship between DTSS and pathological characteristics.

RESULTS

Clinical performance and the DTSS score were used to determine histopathological severity. The sinusoidal congestion area (SCA), central venous endothelial injury (CVEI), and fibrinoid exudation in congestion foci (FECF) were significant indicators. SCA was linearly related to the DTSS score.

CONCLUSION

Our findings show that hepatic pathological characteristics correlate with DTSS scores in PA-HSOS. SCA, CVEI, and FECF may be helpful for determining PA-HSOS severity.

Transjugular intrahepatic portosystemic shunt for the treatment of hepatic sinusoidal obstruction syndrome caused by pyrrolizidine alkaloids: A multicenter retrospective study

Purpose

To assess the impact of transjugular intrahepatic portosystemic shunt (TIPS) on clinical outcomes and liver histology in patients with hepatic sinusoidal obstruction syndrome (HSOS) caused by pyrrolizidine alkaloids (PA), and compare these results with those of patients who received supportive treatment alone.

Materials and methods

From June 2015 to August 2022, 164 patients diagnosed with PA-HSOS in six tertiary care centers were retrospectively included in this study and divided into TIPS group (n = 69) and supportive treatment (ST) group (n = 95). The main endpoint was to determine whether TIPS placement could improve survival in PA-HSOS patients. The clinical symptoms associated with portal hypertension were also evaluated in this study. Additionally, a small TIPS-subgroup of 7 patients received liver biopsies before and after TIPS for histological analysis.

Results

The incidence of death was markedly lower in the TIPS group than in the ST group (log-rank p = 0.026). Multivariate Cox model revealed that group assignment (hazard ratio (HR) 5.146; 95 % confidence interval (CI) 1.587-16.687; p = 0.006), total bilirubin (HR 1.029; 95 % CI 1.020-1.038; p < 0.001), and INR (HR 13.291; 95 % CI 3.637-48.566; p < 0.001) were independent predictors for mortality. In addition, TIPS placement reduced the risk of complications associated with portal hypertension but did not increase the rate of overt hepatic encephalopathy (log-rank p = 0.731). Furthermore, six of 7 TIPS patients receiving liver biopsies improved after TIPS placement, and one patient developed fibrosis.

Conclusions

TIPS placement decreased the mortality and risk of complications associated with portal hypertension. Histological evaluation in a few patients showed a potential improvement by TIPS.

Gut microbiota promotes macrophage M1 polarization in hepatic sinusoidal obstruction syndrome via regulating intestinal barrier function mediated by butyrate

BACKGROUND

The intestinal-liver axis is associated with various liver diseases. Here, we verified the role of the gut microbiota and macrophage activation in the progression of pyrrolizidine alkaloids-induced hepatic sinusoidal obstruction syndrome (PA-HSOS), and explored the possible mechanisms and new treatment options.

METHODS

The HSOS murine model was induced by gavage of monocrotaline (MCT). An analysis of 16S ribosomal DNA (16S rDNA) of the feces was conducted to determine the composition of the fecal microbiota. Macrophage clearance, fecal microbiota transplantation (FMT), and butyrate supplementation experiments were used to assess the role of intestinal flora, gut barrier, and macrophage activation and to explore the relationships among these three variables.

RESULTS

Activated macrophages and low microflora diversity were observed in HSOS patients and murine models. Depletion of macrophages attenuated inflammatory reactions and apoptosis in the mouse liver. Moreover, compared with control-FMT mice, the exacerbation of severe liver injury was detected in HSOS-FMT mice. Specifically, butyrate fecal concentrations were significantly reduced in HSOS mice, and administration of butyrate could partially alleviated liver damage and improved the intestinal barrier in vitro and in vivo. Furthermore, elevated lipopolysaccharides in the portal vein and high proportions of M1 macrophages in the liver were also detected in HSOS-FMT mice and mice without butyrate treatment, which resulted in severe inflammatory responses and further accelerated HSOS progression.

CONCLUSIONS

These results suggested that the gut microbiota exacerbated HSOS progression by regulating macrophage M1 polarization via altered intestinal barrier function mediated by butyrate. Our study has identified new strategies for the clinical treatment of HSOS.

Neuroprotective Effect of Lithospermum officinale Callus Extract on Inflamed Primary Microglial Cells

BACKGROUND

Plants that have therapeutic features for humans or animals are commonly referred to as "medicinal plants". They produce secondary metabolites with antioxidant, antimicrobial and/or anti-cancer effects. Lithospermum officinale, known as European stone seed, is a famous medicinal herb. However, due to the pyrrolizidine alkaloids (PzAl) in the root extract of L.officinal, there are therapeutic limitations to this herb.

OBJECTIVE

This research was devoted to the evaluation of the anti-inflammatory capacity of methanolic extracts of L. officinale callus (LoE) (fresh cells) on rat microglial cells, the immune cells of the Central Nervous System, which play an essential role in the responses to neuroinflammation.

METHODS

Primary microglia were obtained from neonatal Wistar rats (1 to 3-days old), and then treated with various concentration of CfA and methanolic extracts of 17 and 31-day-old L. officinale callus before LPS-stimulation. In addition to HPLC analysis of the extracts, viability, nitric oxide production, and evaluation of pro-inflammatory genes and cytokines in the inflamed microglia were investigated by MTT, Griess methos, qrt-PCR, and ELISA.

RESULTS

Methanolic extract of the 17-day-old callus of L. officinale exhibited anti-inflammatory effects on LPS-stimulated microglial cells much higher than observed for CfA. The data were further supported by the decreased expression of Nos2, Tnf-α, and Cox-2 mRNA and the suppression of TNF-α and IL-1β release in the activated microglial cells pretreated with the effective dose of LoE (0.8 mg mL-1).

CONCLUSION

It was assumed that the better anti-neuroinflammatory performance of LoE than CfA in LPS-activated primary microglia could be a result of the synergism of the components of the extract and the lipophilic nature of RsA as the main phenolic acid of LoE. Considering that LoE shows a high antioxidant capacity and lacks PzAl, it is anticipated that LoE extract might be considered a reliable substitute to play a key role in the preparation of neuroprotective pharmaceutical formulas, which require in vivo research and further experiments.