Krill oil prevents lipopolysaccharide-evoked acute liver injury in mice through inhibition of oxidative stress and inflammation

Extraction of high-quality Antarctic krill (Euphausia Superba) oil using low-temperature continuous phase-transition extraction equipment

The aim of this study was to explore a processing method for efficient extraction of high-quality krill oil (KO) using a low-temperature continuous phase-transition extraction equipment (LCPE). The efficiency of lipid extraction and quality of KO and defatted krill meal (DKM) by LCPE were compared with those of supercritical CO2 and n-hexane extraction. Results showed that compared to other methods, extraction using LCPE had the highest lipid yield (21.72 ± 0.34%), bioactive substances, and dimethyl sulfide (3.12 ± 0.09 mg/kg), the lowest oxidative deterioration. Moreover, compared to other methods, DKM extracted by LCPE had the lowest fat (<2%), the highest protein (>60%), and the best oxidative stability. These benefits would ensure easier transportation and better long-term storage, allowing for its application on distant-ocean fishing vessels. Therefore, LCPE is a method that allows for efficient extraction of high-quality KO.

Transcriptomic and Metabolomic Analyses Reveal the Attenuating Role of Cordycepin and Cordyceps militaris Extract on Acute Liver Injury Induced by LPS in Piglets

Cordyceps militaris extract (CME) contains many bioactive compounds, mainly cordycepin (CPN). This study aimed to investigate the possible mechanisms underlying the amelioration of LPS-induced acute liver injury in piglets by CME or CPN supplementation using multi-omics analysis. Twenty-four weaned piglets were randomly distributed into 4 groups (n = 6): the control and LPS groups were fed basal diets; the CPN + LPS (CPN-LPS) and CME + LPS (CME-LPS) groups were fed the basal diets supplemented with CME or CPN. The results showed that CPN or CME supplementation significantly decreased the C-reactive protein level (p < 0.05) and improved liver tissue pathology to prevent acute liver injury after LPS treatment. Compared with LPS, the transcriptomic analysis indicated that CPN supplementation significantly downregulated cell adhesion molecules, while CME supplementation significantly downregulated inflammatory mediator regulation of TRP channels, complement and coagulation cascades and cytokine-cytokine receptor interaction. The metabolomic results showed that CPN or CME supplementation significantly reduced disease biomarker of bicyclo-prostaglandin E2, and increased levels of deoxyinosine and 3-hydroxyanthranilic acid (p < 0.05). The combined transcriptome and metabolome helped identify two metabolites PC 34:2 and PC 36:0, which may be associated with the restoration of liver cell morphology. In conclusion, CPN and CME could attenuate LPS-induced acute liver injury by regulating immune-related genes and metabolites. This study elucidates the potential protective mechanism of CPN or CME supplementation against acute liver injury.

Influence of lipid oxidation on the digestive efficiency of Antarctic krill oil: insights from a simulated gastrointestinal digestion model

Lipid oxidation profoundly impacts its digestibility, a topic that has been predominantly investigated in triglyceride (TAG)-based dietary lipids. However, there is a dearth of similar research on lipids with diverse classes, such as Antarctic krill oil (AKO), which encompasses a spectrum of lipids including glycerides and phospholipids. This study aimed to elucidate the influence of lipid oxidation on the digestibility of AKO through a simulated gastrointestinal digestion (SGID) model. Post-SGID, AKO exhibited oxidative changes, evidenced by an escalation in peroxide value, conjugated diene value, thiobarbituric acid reactive substances and Schiff base formation. Concurrently, the digestibility of oxidized AKO was found to be inferior to that of fresh AKO, as indicated by a diminished hydrolysis degree of TAGs and phosphatidylcholine (PC), along with a reduced release of free fatty acids. Furthermore, co-digestion with tea polyphenol palmitate was observed to mitigate the oxidation of AKO and the digestion of PC during the SGID, while exerting no significant impact on TAG digestion. Notably, the emulsification capacity of oxidized AKO in a simulated intestinal fluid (without pancreatin and phospholipase A2) was also found to be inferior to that of its fresh counterpart. These findings suggest that lipid oxidation may adversely affect the emulsification capacity of AKO under simulated intestinal conditions, thereby leading to a decrement in digestibility.

Fecal microbiota transplantation alleviates intestinal inflammatory diarrhea caused by oxidative stress and pyroptosis via reducing gut microbiota-derived lipopolysaccharides

Infancy is a critical period in the maturation of the gut microbiota and a phase of susceptibility to gut microbiota dysbiosis. Early disturbances in the gut microbiota can have long-lasting effects on host physiology, including intestinal injury and diarrhea. Fecal microbiota transplantation (FMT) can remodel gut microbiota and may be an effective way to treat infant diarrhea. However, limited research has been conducted on the mechanisms of infant diarrhea and the regulation of gut microbiota balance through FMT, primarily due to ethical challenges in testing on human infants. Our study demonstrated that elevated Lipopolysaccharides (LPS) levels in piglets with diarrhea were associated with colon microbiota dysbiosis induced by early weaning. Additionally, LPS upregulated NLRP3 levels by activating TLR4 and inducing ROS production, resulting in pyroptosis, disruption of the intestinal barrier, bacterial translocation, and subsequent inflammation, ultimately leading to diarrhea in piglets. Through microbiota regulation, FMT modulated β-PBD-2 secretion in the colon by increasing butyric acid levels. This modulation alleviated gut microbiota dysbiosis, reduced LPS levels, attenuated oxidative stress and pyroptosis, inhibited the inflammatory response, maintained the integrity of the intestinal barrier, and ultimately reduced diarrhea in piglets caused by colitis. These findings present a novel perspective on the pathogenesis, pathophysiology, prevention, and treatment of diarrhea diseases, underscoring the significance of the interaction between FMT and the gut microbiota as a critical strategy for treating diarrhea and intestinal diseases in infants and farm animals.

Hesperetin derivative 2a inhibits lipopolysaccharide-induced acute liver injury in mice via downregulation of circDcbld2

Acute liver injury (ALI) is a complex, life-threatening inflammatory liver disease, and persistent liver damage leads to rapid decline and even failure of liver function. However, the pathogenesis of ALI is still not fully understood, and no effective treatment has been discovered. Recent evidence shows that many circular RNAs (circRNAs) are associated with the occurrence of liver diseases. In this study we investigated the mechanisms of occurrence and development of ALI in lipopolysaccharide (LPS)-induced ALI mice. We found that expression of the circular RNA circDcbld2 was significantly elevated in the liver tissues of ALI mice and LPS-treated RAW264.7 cells. Knockdown of circDcbld2 markedly alleviates LPS-induced inflammatory responses in ALI mice and RAW264.7 cells. We designed and synthesized a series of hesperidin derivatives for circDcbld2, and found that hesperetin derivative 2a (HD-2a) at the concentrations of 2, 4, 8 μM effectively inhibited circDcbld2 expression in RAW264.7 cells. Administration of HD-2a (50, 100, 200 mg/kg. i.g., once 24 h in advance) effectively relieved LPS-induced liver dysfunction and inflammatory responses. RNA sequencing analysis revealed that the anti-inflammatory and hepatoprotective effects of HD-2a were mediated through downregulating circDcbld2 and suppressing the JAK2/STAT3 pathway. We conclude that HD-2a downregulates circDcbld2 to inhibit the JAK2/STAT3 pathway, thereby inhibiting the inflammatory responses in ALI. The results suggest that circDcbld2 may be a potential target for the prevention and treatment of ALI, and HD-2a may have potential as a drug for the treatment of ALI.

Preparation of microgels loaded with lycopene/NMN and their protective mechanism against acute liver injury

This study aimed to enhance the stability and bioavailability of lycopene (LYC) and nicotinamide mononucleotide (NMN) by incorporating them into porous microgels after loading LYC into liposomes. The particle size, zeta potential, encapsulation rate (%), scanning electron microscopy images, and stability and release kinetics characteristics in simulating digestion confirmed that the microgels had high LYC and NMN encapsulation rates (99.11% ± 0.12% and 68.98% ± 0.26%, respectively) and good stability and release characteristics. The protective effect and potential mechanism of microgels loaded with LYC and NMN on lipopolysaccharide (LPS)-induced acute liver injury in C57BL/6 mice were investigated by intragastric administration for 28 days prior to LPS exposure. The results showed that the microgels loaded with LYC and NMN significantly ameliorated LPS-induced liver injury and reduced the inflammatory response and oxidative stress. In addition, LYC and NMN can not only act on the Toll-like receptor 4 (TLR4)/MD2 complex but also regulate TLR4-related miRNAs (miR-145a-5p and miR-217-5p) in serum extracellular vesicles, thereby synergistically inhibiting the TLR4/NF-κB signaling pathway. In addition, the microgels loaded with LYC and NMN were able to enrich beneficial bacteria that produced short-chain fatty acids and reduce harmful bacteria. In conclusion, LYC and NMN protected against LPS-induced acute liver injury via inhibition of oxidative stress and inflammation, as well as regulating the gut microbiota.