Adsorption of histones on natural polysaccharides: The potential as agent for multiple organ failure in sepsis

Histones are critical toxic factors in gut lymph of severe acute pancreatitis: Neutralization by baicalin and baicalein for protection

BACKGROUND

Whether circulating histones in gut lymph contribute to organ failure and impact of chaiqin chengqi decoction (CQCQD) on histones in severe acute pancreatitis (SAP) remain elusive.

PURPOSE

To verify the role of histones in gut lymph of SAP and evaluate the effect of the CQCQD on them.

METHODS

Sodium taurocholate was retrogradely infused into pancreatobiliary duct to induce SAP in rodents. Various regimens of CQCQD were administered intragastrically or via duodenum followed by dynamic gut lymph collection in rats. The impact of gut lymph and histones on endothelial cell viability and lymphocytes was determined. Components of CQCQD in gut lymph were identified by UHPLC-MS and their binding activities with histones were quantified by biolayer interferometry followed by validation in vitro and in vivo in mice.

RESULTS

The histone level was significantly increased in gut lymph of SAP at various time points assessed, closely correlating with multiple organ injury (MOI) indices and contemporary cell viability. Inhibition of histones reduced cytotoxicity induced by SAP-conditioned gut lymph. CQCQD reduced apoptotic cell death in mesenteric lymph nodes, histone level, and cytotoxicity of gut lymph, alleviating MOI parameters. Baicalin and baicalein were amongst top 13 identified CQCQD components absorbed into gut lymph to actively bind histones, block membrane disruption and calcium influx of lymphocytes, and inhibit their cytotoxicity. Both baicalin and baicalein mitigated histone- and SAP-induced MOI indices in mice.

CONCLUSION

Histones are key toxic factors in the gut lymph of SAP and their antagonism by baicalin and baicalein offers a novel therapeutic strategy.

Associations between serum albumin level trajectories and clinical outcomes in sepsis patients in ICU: insights from longitudinal group trajectory modeling

Background

Sepsis triggers a strong inflammatory response, often leading to organ failure and high mortality. The role of serum albumin levels in sepsis is critical but not fully understood, particularly regarding the significance of albumin level changes over time. This study utilized Group-based Trajectory Modeling (GBTM) to investigate the patterns of serum albumin changes and their impact on sepsis outcomes.

Methods

We conducted a retrospective analysis on ICU patients from West China Hospital (2015-2022), employing GBTM to study serum albumin fluctuations within the first week of ICU admission. The study factored in demographics, clinical parameters, and comorbidities, handling missing data through multiple imputation. Outcomes assessed included 28-day mortality, overall hospital mortality, and secondary complications such as AKI and the need for mechanical ventilation.

Results

Data from 1,950 patients revealed four serum albumin trajectories, showing distinct patterns of consistently low, increasing, moderate, and consistently high levels. These groups differed significantly in mortality, with the consistently low level group experiencing the highest mortality. No significant difference in 28-day mortality was observed among the other groups. Subgroup analysis did not alter these findings.

Conclusion

The study identified four albumin trajectory groups in sepsis patients, highlighting that those with persistently low levels had the worst outcomes, while those with increasing levels had the best. Stable high levels above 30 g/L did not change outcomes significantly. These findings can inform clinical decisions, helping to identify high-risk patients early and tailor treatment approaches.

Effect of Cross-Linking Cations on In Vitro Biocompatibility of Apple Pectin Gel Beads

The study aimed to compare the in vitro biocompatibility of pectin gels formed by different cross-linking cations. Hydrogel beads named CaPG, ZnPG, FePG, and AlPG were prepared from 4% solutions of apple pectin using ionotropic gelling with CaCl2, ZnCl2, FeCl3, and AlCl3, respectively. Cations influenced the gel strength of the wet gel beads in the following order (least strong) Ca2+ < Zn2+ < Fe3+~Al3+ (most strong). The swelling degree of the CaPG beads after 24 h of incubation in the RPMI-1640 medium was 104%, whereas the ZnPG, FePG, and AlPG beads swelled by 76, 108, and 134%, respectively. The strength of the pectin gel decreased significantly after incubation in the RPMI-1640 medium for 24 h, regardless of the cross-linking cation, although the FePG beads remained the strongest. All the pectin beads adsorbed serum proteins to a low degree, however the serum protein adsorption by the ZnPG and FePG beads (1.46 ± 0.87 and 1.35 ± 0.19 µg/mm2) was more than the CaPG and AlPG beads (0.31 ± 0.36 and 0.44 ± 0.25 µg/mm2). All the pectin beads reduced the production of TNF-α and IL-10 by hPBMCs in response to LPS stimulation. The IL-1β response of cells to LPS was significantly reduced by the CaPG, ZnPG, and FePG beads, whereas the AlPG beads enhanced it twofold. The CaPG, FePG, and AlPG beads had no cytotoxicity. The viability of hPBMCs and human fibroblasts incubated with ZnPG beads was 5.3 and 7.2%, respectively. Thus, the use of different cross-linking cations changed the properties of the pectin gel, which is important for biocompatibility.

Circulating Histones in Sepsis: Potential Outcome Predictors and Therapeutic Targets

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection and is associated with high morbidity and mortality. Circulating histones (CHs), a group of damage-associated molecular pattern molecules mainly derived from neutrophil extracellular traps, play a crucial role in sepsis by mediating inflammation response, organ injury and death through Toll-like receptors or inflammasome pathways. Herein, we first elucidate the molecular mechanisms of histone-induced inflammation amplification, endothelium injury and cascade coagulation activation, and discuss the close correlation between elevated level of CHs and disease severity as well as mortality in patients with sepsis. Furthermore, current state-of-the-art on anti-histone therapy with antibodies, histone-binding proteins (namely recombinant thrombomodulin and activated protein C), and heparin is summarized to propose promising approaches for sepsis treatment.

Chaiqin chengqi decoction alleviates severity of acute pancreatitis via inhibition of TLR4 and NLRP3 inflammasome: Identification of bioactive ingredients via pharmacological sub-network analysis and experimental validation

BACKGROUND

Chaiqin chengqi decoction (CQCQD) is a Chinese herbal formula derived from dachengqi decoction. CQCQD has been used for the management of acute pancreatitis (AP) in the West China Hospital for more than 30 years. Although CQCQD has a well-established clinical efficacy, little is known about its bioactive ingredients, how they interact with different therapeutic targets and the pathways to produce anti-inflammatory effects.

PURPOSE

Toll-like receptor 4 (TLR4) and the nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated pro-inflammatory signaling pathways, play a central role in AP in determining the extent of pancreatic injury and systemic inflammation. In this study, we screened the bioactive ingredients using a pharmacological sub-network analysis based on the TLR4/NLRP3 signaling pathways followed by experimental validation.

METHODS

The main CQCQD bioactive compounds were identified by UPLC-QTOF/MS. The TLR4/NLRP3 targets in AP for CQCQD active ingredients were confirmed through a pharmacological sub-network analysis. Mice received 7 intraperitoneal injections of cerulein (50 μg/kg; hourly) to induce AP (CER-AP), while oral gavage of CQCQD (5, 10, 15 and 20 g/kg; 3 doses, 2 hourly) was commenced at the 3rd injection of cerulein. Histopathology and biochemical indices were used for assessing AP severity, while polymerase chain reaction, Western blot and immunohistochemistry analyses were used to study the mechanisms. Identified active CQCQD compounds were further validated in freshly isolated mouse pancreatic acinar cells and cultured RAW264.7 macrophages.

RESULTS

The main compounds from CQCQD belonged to flavonoids, iridoids, phenols, lignans, anthraquinones and corresponding glycosides. The sub-network analysis revealed that emodin, rhein, baicalin and chrysin were the compounds most relevant for directly regulating the TLR4/NLRP3-related proteins TLR4, RelA, NF-κB and TNF-α. In vivo, CQCQD attenuated the pancreatic injury and systemic inflammation of CER-AP and was associated with reduced expression of TLR4/NLRP3-related mRNAs and proteins. Emodin, rhein, baicalin and chrysin significantly diminished pancreatic acinar cell necrosis with varied effects on suppressing the expression of TLR4/NLRP3-related mRNAs. Emodin, rhein and chrysin also decreased nitric oxide production in macrophages and their combination had synergistic effects on alleviating cell death as well as expression of TLR4/NLRP3-related proteins.

CONCLUSIONS

CQCQD attenuated the severity of AP at least in part by inhibiting the TLR4/NLRP3 pro-inflammatory pathways. Its active ingredients, emodin, baicalin, rhein and chrysin contributed to these beneficial effects.

Controlling evolution of protein corona: a prosperous approach to improve chitosan-based nanoparticle biodistribution and half-life

Protein corona significantly affects in vivo fate of nanoparticles including biodistribution and half-life. Without manipulating the physicochemical properties of nanoparticles with considering their biointerference, attaining effective treatment protocols is impossible. For this reason, protein corona evolution and biodistribution of different chitosan (Ch)-based nanoparticles including Ch and carboxymethyl dextran (CMD)/thiolated dextran (TD) polyelectrolyte complexes (PECs) were studied using highly precious and sensitive methods such as liquid chromatography-mass/mass (LC-MS/MS) spectroscopy and positron emission tomography/computed tomography (PET/CT) scan. The importance of serum presence/absence in culture medium with different pH and corona effect on cellular uptake of PECs investigated by in vitro study. Designed PECs have low amounts of proteins in corona mostly enriched by Apolipoproteins, protein C, hemoglobin subunits, and inter-alpha- trypsin inhibitor that beside improving uptake of nanoparticles, they have low liver uptake and notable heart blood pool accumulation that confirmed the long circulation time of the nanoparticles which is favorable for delivery of nanoparticles to the site of action and achieving required therapeutic effect.