Malvidin protects against lipopolysaccharide-induced acute liver injury in mice via regulating Nrf2 and NLRP3 pathways and suppressing apoptosis and autophagy

Natural products act as game-changer potentially in treatment and management of sepsis-mediated inflammation: A clinical perspective

BACKGROUND

Sepsis, a life-threatening condition resulting from uncontrolled host responses to infection, poses a global health challenge with limited therapeutic options. Due to high heterogeneity, sepsis lacks specific therapeutic drugs. Additionally, there remains a significant gap in the clinical management of sepsis regarding personalized and precise medicine.

PURPOSE

This review critically examines the scientific landscape surrounding natural products in sepsis and sepsis-mediated inflammation, highlighting their clinical potential.

METHODS

Following the PRISMA guidelines, we retrieved articles from PubMed to explore potential natural products with therapeutic effects in sepsis-mediated inflammation.

RESULTS

434 relevant in vitro and in vivo studies were identified and screened. Ultimately, 55 studies were obtained as the supporting resources for the present review. We divided the 55 natural products into three categories: those influencing the synthesis of inflammatory factors, those affecting surface receptors and modulatory factors, and those influencing signaling pathways and the inflammatory cascade.

CONCLUSION

Natural products' potential as game-changers in sepsis-mediated inflammation management lies in their ability to modulate hallmarks in sepsis, including inflammation, immunity, and coagulopathy, which provides new therapeutic avenues that are readily accessible and capable of undergoing rapid clinical validation and deployment, offering a gift from nature to humanity. Innovative techniques like bioinformatics, metabolomics, and systems biology offer promising solutions to overcome these obstacles and facilitate the development of natural product-based therapeutics, holding promise for personalized and precise sepsis management and improving patient outcomes. However, standardization, bioavailability, and safety challenges arise during experimental validation and clinical trials of natural products.

Liensinine alleviates sepsis-induced acute liver injury by inhibiting the NF-κB and MAPK pathways in an Nrf2-dependent manner

Sepsis remains a serious public health issue that needs to be addressed globally. Severe liver injury caused by sepsis increases the risk of death in patients with sepsis. Liensinine (Lie) is one of the primary active components in Plumula nelumbinis and has anti-inflammatory and antioxidant effects. Nevertheless, the effects of Lie on septic liver injury are unclear. This research investigated the protective effect of Lie (10, 20 and 40 mg/kg) on liver damage via intraperitoneal administration of LPS (10 mg/kg) to C57BL/6 mice. Lie was given through intraperitoneal injection once a day for five days. Mice were treated with LPS intraperitoneally for 6 h at 1 h after Lie administration on the last day. The results suggested that Lie could decrease AST and ALT levels in serum, ameliorate histopathological changes and inhibit cell apoptosis in mice with LPS-induced septic liver injury. In addition, Lie inhibited increases in the mRNA levels of TNF-α, IL-1β, iNOS and IL-6. Lie also increased the mRNA level of IL-10. Lie reduced the content of MDA, a marker of lipid peroxidation, and increased the activity of the antioxidant enzymes GSH-Px, CAT and SOD. Our results also showed that Lie could suppress the LPS-activated MAPK and NF-κB pathways and trigger the Nrf2 signaling pathway both in vitro and in vivo. Additionally, an Nrf2 inhibitor (ML385) weakened the suppressive effect of Lie on the MAPK and NF-κB pathways. Our results demonstrated that the suppressive effect of Lie on the MAPK and NF-κB pathways was partially reliant on activation of the Nrf2 pathway. In summary, these results indicate that Lie can improve inflammation and oxidative stress by activating Nrf2, which is a prospective therapeutic drug for alleviating septic liver injury.

IRG1/itaconate alleviates acute liver injury in septic mice by suppressing NLRP3 expression and its mediated macrophage pyroptosis via regulation of the Nrf2 pathway

Sepsis, a systemic inflammatory response triggered by infection, has a considerably high mortality rate. However, effective prevention and intervention measures against sepsis remain insufficient. Therefore, this study aimed to investigate the mechanisms underlying the protective properties of immune response gene-1 (IRG1) and 4-Octyl itaconate (OI) during acute liver damage in mice with sepsis. A sepsis mouse model was established to compare wild-type and IRG1-/- groups. The impact of IRG1/Itaconate on pro- and anti-inflammatory cytokines was evaluated using J774A.1 cells. IRG1/Itaconate substantially reduced pro-inflammatory cytokines and increased the release of anti-inflammatory cytokines. It reduced pathological damage to liver tissues, preserved normal liver function, decreased the release of reactive oxygen species (ROS) and LDH, and enhanced the GSH/GSSG ratio. Moreover, IRG1 and itaconic acid activated the Nrf2 signaling pathway, regulating the expression of its downstream antioxidative stress-related proteins. Additionally, they inhibited the activity of NLRP3 inflammatory vesicles to suppress the expression of macrophage-associated pyroptosis signaling molecules. Our findings demonstrate that IRG1/OI inhibits NLRP3 inflammatory vesicle activation and macrophage pyroptosis by modulating the Nrf2 signaling pathway, thereby attenuating acute liver injury in mice with sepsis. These findings could facilitate the clinical application of IRG1/Itaconate to prevent sepsis-induced acute liver injury.

Malvidin attenuates trauma-induced heterotopic ossification of tendon in rats by targeting Rheb for degradation via the ubiquitin-proteasome pathway

The pathogenesis of trauma-induced heterotopic ossification (HO) in the tendon remains unclear, posing a challenging hurdle in treatment. Recognizing inflammation as the root cause of HO, anti-inflammatory agents hold promise for its management. Malvidin (MA), possessing anti-inflammatory properties, emerges as a potential agent to impede HO progression. This study aimed to investigate the effect of MA in treating trauma-induced HO and unravel its underlying mechanisms. Herein, the effectiveness of MA in preventing HO formation was assessed through local injection in a rat model. The potential mechanism underlying MA's treatment was investigated in the tendon-resident progenitor cells of tendon-derived stem cells (TDSCs), exploring its pathway in HO formation. The findings demonstrated that MA effectively hindered the osteogenic differentiation of TDSCs by inhibiting the mTORC1 signalling pathway, consequently impeding the progression of trauma-induced HO of Achilles tendon in rats. Specifically, MA facilitated the degradation of Rheb through the K48-linked ubiquitination-proteasome pathway by modulating USP4 and intercepted the interaction between Rheb and the mTORC1 complex, thus inhibiting the mTORC1 signalling pathway. Hence, MA presents itself as a promising candidate for treating trauma-induced HO in the Achilles tendon, acting by targeting Rheb for degradation through the ubiquitin-proteasome pathway.

Active Components of Pueraria lobata through the MAPK/ERK Signaling Pathway Alleviate Iron Overload in Alcoholic Liver Disease

OBJECTIVE

To delve into the primary active ingredients and mechanism of Pueraria lobata for alleviating iron overload in alcoholic liver disease.

METHODS

Pueraria lobata's potential targets and signaling pathways in treating alcohol-induced iron overloads were predicted using network pharmacology analysis. Then, animal experiments were used to validate the predictions of network pharmacology. The impact of puerarin or genistein on alcohol-induced iron accumulation, liver injury, oxidative stress, and apoptosis was assessed using morphological examination, biochemical index test, and immunofluorescence. Key proteins implicated in linked pathways were identified using RT-qPCR, western blot analysis, and immunohistochemistry.

RESULTS

Network pharmacological predictions combined with animal experiments suggest that the model group compared to the control group, exhibited activation of the MAPK/ERK signaling pathway, suppression of hepcidin expression, and aggravated iron overload, liver damage, oxidative stress, and hepatocyte death. Puerarin and genistein, the active compounds in Pueraria lobata, effectively mitigated the aforementioned alcohol-induced effects. No statistically significant disparities were seen in the effects above between the two groups receiving drug therapy.

CONCLUSION

This study preliminarily demonstrated that puerarin and genistein in Pueraria lobata may increase hepcidin production to alleviate alcohol-induced iron overload by inhibiting the MAPK/ERK signaling pathway.

Ginsenoside Rg1 attenuates lipopolysaccharide-induced chronic liver damage by activating Nrf2 signaling and inhibiting inflammasomes in hepatic cells

ETHNOPHARMACOLOGICAL RELEVANCE

Ginseng (Panax ginseng C. A. Meyer) is a precious traditional Chinese medicine with multiple pharmacological effects. Ginsenoside Rg1 is a main active ingredient extracted from ginseng, which is known for its age-delaying and antioxidant effects. Increasing evidence indicates that Rg1 exhibits anti-inflammatory properties in numerous diseases and may ameliorate oxidative damage and inflammation in many chronic liver diseases.

AIM OF THE STUDY

Chronic inflammatory injury in liver cells is an important pathological basis of many liver diseases. However, its mechanism remains unclear and therapeutic strategies to prevent its development need to be further explored. Thus, our study is to delve the protective effect and mechanism of Rg1 against chronic hepatic inflammatory injuries induced by lipopolysaccharide (LPS).

MATERIALS AND METHODS

The chronic liver damage model in mice was build up by injecting intraperitoneally with LPS (200 μg/kg) for 21 days. Serum liver function indicators and levels of IL-1β, IL-6 and TNF-α were examined by using corresponding Kits. Hematoxylin and Eosin (H&E), Periodic acid-Schiff (PAS), and Masson stains were utilized to visualize hepatic histopathological damage, glycogen deposition, and liver fibrosis. The nuclear import of p-Nrf2 and the generation of Col4 in the liver were detected by IF, while IHC was employed to detect the expressions of NLRP3 and AIM2 in the hepatic. The Western blot and q-PCR were used to survey the expressions of proteins and mRNAs of fibrosis and apoptosis, and the expressions of Keap1, p-Nrf2 and NLRP3, NLRP1, AIM2 inflammasome-related proteins in mouse liver. The cell viability of human hepatocellular carcinoma cells (HepG2) was detected by Cell Counting Kit-8 to select the action concentration of LPS, and intracellular ROS generation was detected using a kit. The expressions of Nuclear Nrf2, HO-1, NQO1 and NLRP3, NLRP1, and AIM2 inflammasome-related proteins in HepG2 cells were detected by Western blot. Finally, the feasibility of the molecular interlinking between Rg1 and Nrf2 was demonstrated by molecular docking.

RESULTS

Rg1 treatment for 21 days decreased the levels of ALT, AST, and inflammatory factors of serum IL-1β, IL-6 and TNF-α in mice induced by LPS. Pathological results indicated that Rg1 treatment obviously alleviated hepatocellular injury and apoptosis, inflammatory cell infiltration and liver fibrosis in LPS stimulated mice. Rg1 promoted Keap1 degradation and enhanced the expressions of p-Nrf2, HO-1 and decreased the levels of NLRP1, NLRP3, AIM2, cleaved caspase-1, IL-1β and IL-6 in livers caused by LPS. Furthermore, Rg1 effectively suppressed the rise of ROS in HepG2 cells induced by LPS, whereas inhibition of Nrf2 reversed the role of Rg1 in reducing the production of ROS and NLRP3, NLRP1, and AIM2 expressions in LPS-stimulated HepG2 cells. Finally, the molecular docking illustrated that Rg1 exhibits a strong affinity towards Nrf2.

CONCLUSION

The findings indicate that Rg1 significantly ameliorates chronic liver damage and fibrosis induced by LPS. The mechanism may be mediated through promoting the dissociation of Nrf2 from Keap1 and then activating Nrf2 signaling and further inhibiting NLRP3, NLRP1, and AIM2 inflammasomes in liver cells.

Grape/Blueberry Anthocyanins and Their Gut-Derived Metabolites Attenuate LPS/Nigericin-Induced Inflammasome Activation by Inhibiting ASC Speck Formation in THP-1 Monocytes

Inflammasomes are multi-protein complexes, which are formed in response to tissue injury, infections, and metabolic stress. However, aberrant inflammasome activation has been linked to several inflammatory diseases. Anthocyanins have been reported to attenuate NLR family pyrin domain-containing 3 (NLRP3) inflammasome activation, but the influence of grape/blueberry anthocyanins and especially their gut-derived metabolites on NLRP3 inflammasome activation in human monocytes remains unclear. Therefore, human leukemic monocytes (THP-1 cells, Tohoku Hospital Pediatrics-1 cells) were preincubated with different concentrations of grape/blueberry anthocyanins, homovanillyl alcohol, or 2,4,6-trihydroxybenzaldehyde (THBA) before the NLRP3 inflammasome was activated by lipopolysaccharide and/or nigericin. Apoptosis-associated speck-like protein containing a CARD (ASC) speck formation, as well as ASC and NLRP3 protein expression, were determined using flow cytometry. Caspase-1 activity was measured in cultured cells, and pro-inflammatory cytokine secretion was determined using enzyme-linked immunosorbent assays. Anthocyanins and their metabolites had no effect on ASC or NLRP3 protein expression. However, THBA significantly inhibited ASC speck formation in primed and unprimed THP-1 monocytes, while caspase-1 activity was significantly declined by grape/blueberry anthocyanins. Furthermore, reduced inflammasome activation resulted in lower pro-inflammatory cytokine secretion. In conclusion, our results show for the first time that grape/blueberry anthocyanins and their gut-derived metabolites exert anti-inflammatory effects by attenuating NLRP3 inflammasome activation in THP-1 monocytes.

Liensinine reduces acute lung injury brought on by lipopolysaccharide by inhibiting the activation of the NF-κB signaling pathway through modification of the Src/TRAF6/TAK1 axis

ALI is characterized by macrophage-driven inflammation, causing severe lung damage. Currently, there are limited therapeutic options available for ALI. Liensinine (LIEN), with known anti-inflammatory properties, lacks extensive study in the ALI context. This study aimed to investigate the impact of LIEN on ALI and elucidate its molecular mechanisms. A total of thirty-six male BALB/c mice altogether were split into six groups: Control, LPS (10 mg/kg), Low (10 mg/kg LIEN + 10 mg/kg LPS), Middle (20 mg/kg LIEN + 10 mg/kg LPS), High (40 mg/kg LIEN + 10 mg/kg LPS), and DEX (2 mg/kg DEX + 10 mg/kg LPS). Lung tissue injury, pulmonary edema, and inflammatory factor levels were evaluated in lung tissues and LPS-stimulated bone marrow-derived macrophages (BMDM). TAK1 activation, TRAF6 ubiquitination, and their interactions were assessed to understand the involved molecular mechanisms. LIEN treatment ameliorated lung tissue injury and suppressed LPS-induced inflammatory factor levels in lung tissues and BMDM. Mechanistically, LIEN inhibited TAK1 activation by disrupting TRAF6-TAK1 interactions, limiting p65's nuclear translocation, and reducing the release of inflammatory factors. According to network pharmacology and molecular docking, LIEN most likely prevents inflammation by interfering directly with the Src. Overexpression of Src in BMDM abolished the regulation of TRAF6 by LIEN, supporting the involvement of the Src/TRAF6/TAK1 axis in its mechanism of action. Based on this study, LIEN treats ALI by modifying the Src/TRAF6/TAK1 axis and blocking the activation of the NF-κB pathway, regulating the release of inflammatory factors. These findings highlight the promise of LIEN as a prospective therapeutic option for the treatment of ALI.

Malvidin alleviates LPS-induced septic intestinal injury through the nuclear factor erythroid 2-related factor 2/reactive oxygen species/NLRP3 inflammasome pathway

Emerging evidence suggests that the gastrointestinal tract plays a crucial role in the pathophysiology of sepsis, a leading cause of mortality among patients admitted to the intensive care unit (ICU). Malvidin, belonging to the flavonoid family of compounds, exhibits a range of capabilities including anti-inflammatory and antioxidant properties. Studies have demonstrated that Malvidin exhibits a dose-dependent effect in mitigating sepsis-induced intestinal injury. The advantageous impact of Malvidin in safeguarding against sepsis-induced intestinal injury is associated with its capacity to counteract oxidative stress, inhibit cellular apoptosis, diminish the secretion of pro-inflammatory cytokines, and regulate the synthesis of inflammasomes. The findings indicate that Malvidin, a natural compound, exhibits protective effects on the gut by activating the nuclear factor erythroid 2-related factor 2/reactive oxygen species/NLRP3 inflammasome pathway. These results have significant implications for potential clinical applications and offer valuable insights into the treatment of sepsis-induced intestinal injury.

Monotropein induces autophagy through activation of the NRF2/PINK axis, thereby alleviating sepsis-induced colonic injury

Sepsis is a systemic inflammatory disease that is caused by a dysregulated host response to infection and is a life-threatening organ dysfunction that affects many organs, which includes the colon. Mounting evidence suggests that sepsis-induced colonic damage is a major contributor to organ failure and cellular dysfunction. Monotropein (MON) is the major natural compound in the iris glycoside that is extracted from Morendae officinalis radix, which possesses the potent pharmacological activities of anti-inflammatory and antioxidant properties. This research evaluated whether MON is able to alleviate septic colonic injury in mice by cecal ligation and puncture. Colonic tissues were analyzed using histopathology, immunofluorescence, quantitative real-time polymerase chain reaction, and Western blot methods. It was initially discovered that MON reduced colonic damage in infected mice, in addition to inflammation, apoptosis, and oxidative stress in colonic tissues, while it activated autophagy, with the NRF2/keap1 and PINK1/Parkin pathways also being activated. Through the stimulation of NCM460 cells with lipopolysaccharides, an in vitro model of sepsis was created as a means of further elucidating the potential mechanisms of MON. In the in vitro model, it was found that MON could still activate the NRF2/keap1, PINK1/Parkin, and autophagy pathways. However, when MON was paired with the NRF2 inhibitor ML385, it counteracted MON-induced activation of PINK1/Parkin and autophagy, while also promoting inflammatory response and apoptosis in NCM460 cells. Therefore, the data implies that MON could play a therapeutic role through the activation of the NFR2/PINK pathway as a means of inducing autophagy to alleviate the oxidative stress in colonic tissues that is induced by sepsis, which will improve inflammation and apoptosis in colonic tissues.

Malvidin promotes PGC-1α/Nrf2 signaling to attenuate the inflammatory response and restore mitochondrial activity in septic acute kidney injury

Acute kidney injury (AKI) in sepsis is a vital and dangerous organ failure caused by an infection-induced dysregulation of the host reaction. Malvidin possesses significant anti-inflammatory and antioxidant bioactivities. This study explored the critical roles of malvidin in sepsis AKI and the crosstalk among mitochondrial function, nucleotide-binding oligomerization-like receptor 3 (NLRP3) inflammasome and nuclear factor erythroid 2 (Nrf2) signaling pathway. First, C57BL/6 mice were administered lipopolysaccharide intraperitoneally for 6 h to create an AKI model of sepsis. Hematoxylin-eosin staining and serum biomarker assays showed that malvidin protected from AKI in sepsis. Real-time fluorescence quantitative polymerase chain reaction analysis revealed that malvidin was able to inhibit inflammatory cytokines and mediators. Western blot assays indicated that malvidin suppressed NLRP3 inflammasome activation and enhanced antioxidant properties. Additionally, human renal tubular epithelial cells were stimulated by lipopolysaccharide/adenosine triphosphate to establish an NLRP3 inflammasome activation model in vitro, and in line with findings in vivo, malvidin significantly inhibited NLRP3 inflammasome activation. Furthermore, our data indicate that malvidin restored mitochondrial quality and function, reduced reactive oxygen species production, increased mitochondrial membrane potential, enhanced mitochondrial DNA copy number, and promoted peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) nuclear translocation. Moreover, inhibitor blockade assays indicated that both PGC-1α and Nrf2 affected the inhibition of the NLRP3 inflammasome by malvidin. Finally, immunoprecipitation assays showed that malvidin promoted PGC-1α and Nrf2 interactions. Overall, malvidin alleviated lipopolysaccharide-induced sepsis AKI, improved mitochondrial function and mitochondrial biogenesis, and inhibited the NLRP3 inflammasome through the PGC-1α/Nrf2 signaling pathway, suggesting that malvidin might translate into clinical applications for sepsis AKI therapy.

Gypenoside XLIX attenuates sepsis-induced splenic injury through inhibiting inflammation and oxidative stress

BACKGROUND

To investigate the effect of Gypenoside XLIX (Gyp-XLIX) on acute splenic injury (ASI) induced by cecal ligation and puncture (CLP) in septic mice, a study was conducted.

METHODS

Sixty healthy mice were randomly divided into six groups: the NC group, the Sham group, the Sham + Gyp-XLIX group, the CLP group, the CLP + Gyp-XLIX group, and the CLP + Dexamethasone (DEX) group. The NC group did not undergo any operation, while the rest of the groups underwent CLP to establish the sepsis model. The Sham group only underwent open-abdominal suture surgery without cecum puncture. After the operation, the groups were immediately administered the drug for a total of 5 days. Various methods such as hematoxylin and eosin (HE) staining, biochemical kits, qRT-PCR, and reactive oxygen species (ROS) were used for analysis.

RESULTS

The results demonstrated that Gyp-XLIX effectively mitigated the splenic histopathological damage, while reducing the malondialdehyde (MDA) lipid peroxidation index and enhancing the antioxidant activities of catalase (CAT), glutathione (GSH) and total antioxidant capacity (T-AOC). The utilization of Dihydroethidium (DHE) fluorescent probe revealed that Gyp-XLIX inhibited the acute splenic accumulation of ROS induced by CLP in septic mice. Further investigations revealed that Gyp-XLIX exhibited a down-regulatory effect on the protein levels of inflammatory mediators iNOS and COX-2, consequently leading to the suppression of pro-inflammatory cytokines such as TNF-α, IL-6, and IL-1β. Additionally, it up-regulated the expression of anti-inflammatory factor IL-10.

CONCLUSION

In conclusion, Gyp-XLIX was significantly effective in attenuating CLP-induced acute splenic inflammation and oxidative stress in septic mice.

Human diet-derived polyphenolic compounds and hepatic diseases: From therapeutic mechanisms to clinical utilization

This review focuses on the potential ameliorative effects of polyphenolic compounds derived from human diet on hepatic diseases. It discusses the molecular mechanisms and recent advancements in clinical applications. Edible polyphenols have been found to play a therapeutic role, particularly in liver injury, liver fibrosis, NAFLD/NASH, and HCC. In the regulation of liver injury, polyphenols exhibit anti-inflammatory and antioxidant effects, primarily targeting the TGF-β, NF-κB/TLR4, PI3K/AKT, and Nrf2/HO-1 signaling pathways. In the regulation of liver fibrosis, polyphenolic compounds effectively reverse the fibrotic process by inhibiting the activation of hepatic stellate cells (HSC). Furthermore, polyphenolic compounds show efficacy against NAFLD/NASH by inhibiting lipid oxidation and accumulation, mediated through the AMPK, SIRT, and PPARγ pathways. Moreover, several polyphenolic compounds exhibit anti-HCC activity by suppressing tumor cell proliferation and metastasis. This inhibition primarily involves blocking Akt and Wnt signaling, as well as inhibiting the epithelial-mesenchymal transition (EMT). Additionally, clinical trials and nutritional evidence support the notion that certain polyphenols can improve liver disease and associated metabolic disorders. However, further fundamental research and clinical trials are warranted to validate the efficacy of dietary polyphenols.

Tangeretin attenuates acute lung injury in septic mice by inhibiting ROS-mediated NLRP3 inflammasome activation via regulating PLK1/AMPK/DRP1 signaling axis

OBJECTIVE

NLRP3 inflammasome-mediated pyroptosis of macrophage acts essential roles in the progression of sepsis-induced acute lung injury (ALI). Tangeretin (TAN), enriched in citrus fruit peel, presents anti-oxidative and anti-inflammatory effects. Here, we aimed to explore the potentially protective effect of TAN on sepsis-induced ALI, and the underlying mechanism of TAN in regulating NLRP3 inflammasome.

MATERIAL AND METHODS

The effect of TAN on sepsis-induced ALI and NLRP3 inflammasome-mediated pyroptosis of macrophage were examined in vivo and in vitro using a LPS-treated mice model and LPS-induced murine macrophages, respectively. The mechanism of TAN regulating the activation of NLRP3 inflammasome in sepsis-induced ALI was investigated with HE staining, Masson staining, immunofluorescent staining, ELISA, molecular docking, transmission electron microscope detection, qRT-PCR, and western blot.

RESULTS

TAN could evidently attenuate sepsis-induced ALI in mice, evidenced by reducing pulmonary edema, pulmonary congestion and lung interstitial fibrosis, and inhibiting macrophage infiltration in the lung tissue. Besides, TAN significantly suppressed inflammatory cytokine IL-1β and IL-18 expression in the serum or bronchoalveolar lavage fluid (BALF) samples of mice with LPS-induced ALI, and inhibited NLRP3 inflammasome-mediated pyroptosis of macrophages. Furthermore, we found TAN inhibited ROS production, preserved mitochondrial morphology, and alleviated excessive mitochondrial fission in LPS-induced ALI in mice. Through bioinformatic analysis and molecular docking, Polo-like kinase 1 (PLK1) was identified as a potential target of TAN for treating sepsis-induced ALI. Moreover, TAN significantly inhibited the reduction of PLK1 expression, AMP-activated protein kinase (AMPK) phosphorylation, and Dynamin related protein 1 (Drp1) phosphorylation (S637) in LPS-induced ALI in mice. In addition, Volasertib, a specific inhibitor of PLK1, abolished the protective effects of TAN against NLRP3 inflammasome-mediated pyroptosis of macrophage and lung injury in the cell and mice septic models.

CONCLUSION

TAN attenuates sepsis-induced ALI by inhibiting ROS-mediated NLRP3 inflammasome activation via regulating PLK1/AMPK/DRP1 signaling axis, and TAN is a potentially therapeutic candidate against ALI through inhibiting pyroptosis.

Novel insights into the regulatory role of N6-methyladenosine methylation modified autophagy in sepsis

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection. It is characterized by high morbidity and mortality and one of the major diseases that seriously hang over global human health. Autophagy is a crucial regulator in the complicated pathophysiological processes of sepsis. The activation of autophagy is known to be of great significance for protecting sepsis induced organ dysfunction. Recent research has demonstrated that N6-methyladenosine (m6A) methylation is a well-known post-transcriptional RNA modification that controls epigenetic and gene expression as well as a number of biological processes in sepsis. In addition, m6A affects the stability, export, splicing and translation of transcripts involved in the autophagic process. Although it has been suggested that m6A methylation regulates the biological metabolic processes of autophagy and is more frequently seen in the progression of sepsis pathogenesis, the underlying molecular mechanisms of m6A-modified autophagy in sepsis have not been thoroughly elucidated. The present article fills this gap by providing an epigenetic review of the processes of m6A-modified autophagy in sepsis and its potential role in the development of novel therapeutics.

Quercetin attenuates avermectin-induced cardiac injury in carp through inflammation, oxidative stress, apoptosis and autophagy

As an important antibiotic, avermectin (AVM) has been widely used in China, but its unreasonable application has caused serious harm to the water environment. In view of the various pharmacological effects of quercetin (QUE), such as anti-inflammatory and antioxidant, the scientific hypothesis that "QUE may cause carp poisoning by inhibiting AVM" was proposed in this study. However, its protective effect in AVM -induced heart damage has not been reported. QUE reduced the symptoms of AVM toxicity and decreased the levels of creatine kinase, lactate dehydrogenase, and creatine kinase in the serum of carp. By histological observation, QUE was found to significantly reduce cardiac fiber swelling in carp. A DHE fluorescence probe study showed that QUE was able to inhibit AVM -induced accumulation of reactive oxygen species (ROS) in carp myocardium. We found that QUE significantly increased the intracellular antioxidant enzymes CAT, T-AOC and GSH enzyme activity and reduced intracellular MDA content. In addition, QUE significantly increased il-10 and tgf-β1 expression, and significantly down-regulated tnf-α, il-6, il-1β and inos expression. Tunel assay showed that QUE attenuated AVM -induced apoptosis, significantly decreased the transcript levels of pro-apoptosis-related genes, and increased the expression of anti-apoptosis-related genes. We also detected the protein expression of LC3 in the AVM group and QUE + AVM group, and found that the expression of LC3 was significantly increased in both groups compared with the Control group, but after adding QUE, the expression of LC3 was significantly decreased compared with the AVM group. In addition, the transcript levels of p62 and atg5 were also detected by qPCR. QUE significantly increased the expression of p62 and decreased the expression of atg5, suggesting that QUE could attenuate AVM -induced cardiac autophagy in carp. This study will provide preliminary evidence of the principle of QUE attenuating AVM -induced myocardial injury in carp from four aspects, including oxidative stress, inflammatory response, apoptosis and autophagy, and provide a theoretical basis for its prevention and treatment.

Flavonoids: Overview of Biosynthesis, Biological Activity, and Current Extraction Techniques

Recently, increased attention has been paid to natural sources as raw materials for the development of new added-value products. Flavonoids are a large family of polyphenols which include several classes based on their basic structure: flavanones, flavones, isoflavones, flavonols, flavanols, and anthocyanins. They have a multitude of biological properties, such as anti-inflammatory, antioxidant, antiviral, antimicrobial, anticancer, cardioprotective, and neuroprotective effects. Current trends of research and development on flavonoids relate to identification, extraction, isolation, physico-chemical characterization, and their applications to health benefits. This review presents an up-to-date survey of the most recent developments in the natural flavonoid classes, the biological activity of representative flavonoids, current extraction techniques, and perspectives.

Bioactive Compounds of the Mediterranean Diet as Nutritional Support to Fight Neurodegenerative Disease

Neurodegenerative disorders are a widespread cause of morbidity and mortality worldwide, characterized by neuroinflammation, oxidative stress, and neuronal depletion. They include selective malfunction and progressive loss of neurons, glial cells, and neural networks in the brain and spinal cord. There is an urgent need to develop new and more effective therapeutic strategies to combat these devastating diseases because, today, there is no treatment that can cure degenerative diseases; however, we have many symptomatic treatments. Current nutritional approaches are beginning to reflect a fundamental change in our understanding of health. The Mediterranean diet may have a protective effect on the neurodegenerative process because it is rich in antioxidants, fiber, and omega-3 polyunsaturated fatty acids. Increasing knowledge regarding the impact of diet on regulation at the genetic and molecular levels is changing the way we consider the role of nutrition, resulting in new dietary strategies. Natural products, thanks to their bioactive compounds, have recently undergone extensive exploration and study for their therapeutic potential for a variety of diseases. Targeting simultaneous multiple mechanisms of action and a neuroprotection approach with the diet could prevent cell death and restore function to damaged neurons. For these reasons, this review will be focused on the therapeutic potential of natural products and the associations between the Mediterranean-style diet (MD), neurodegenerative diseases, and markers and mechanisms of neurodegeneration.

Role of Plant-Derived Compounds in the Molecular Pathways Related to Inflammation

Inflammation is the primary response to infection and injury. Its beneficial effect is an immediate resolution of the pathophysiological event. However, sustained production of inflammatory mediators such as reactive oxygen species and cytokines may cause alterations in DNA integrity and lead to malignant cell transformation and cancer. More attention has recently been paid to pyroptosis, which is an inflammatory necrosis that activates inflammasomes and the secretion of cytokines. Taking into consideration that phenolic compounds are widely available in diet and medicinal plants, their role in the prevention and support of the treatment of chronic diseases is apparent. Recently, much attention has been paid to explaining the significance of isolated compounds in the molecular pathways related to inflammation. Therefore, this review aimed to screen reports concerning the molecular mode of action assigned to phenolic compounds. The most representative compounds from the classes of flavonoids, tannins, phenolic acids, and phenolic glycosides were selected for this review. Our attention was focused mainly on nuclear factor-κB (NF-κB), nuclear factor erythroid 2-related factor 2 (Nrf2), and mitogen-activated protein kinase (MAPK) signaling pathways. Literature searching was performed using Scopus, PubMed, and Medline databases. In conclusion, based on the available literature, phenolic compounds regulate NF-κB, Nrf2, and MAPK signaling, which supports their potential role in chronic inflammatory disorders, including osteoarthritis, neurodegenerative diseases, cardiovascular, and pulmonary disorders.

A Comprehensive Review of the Pharmacological Importance of Dietary Flavonoids as Hepatoprotective Agents

The liver is a crucial organ that is involved in various kinds of metabolic activity and a very stable accessory gland for the digestive system. Long-term or persistent inflammation and oxidative stress due to any reasons have a substantial impact on the beginning and continuation of chronic diseases such as hepatocellular carcinoma, liver cirrhosis, liver fibrosis, and other hepatic conditions. There are many sources which can help the liver to be healthy and enhance its metabolic potential of the liver. Since the diet is rich origin of bioactive along with antioxidant chemicals including flavonoids and polyphenols, it can control different stages of inflammation and hepatic diseases. Numerous food sources, notably vegetables, nuts, fruits, cereals, beverages, and herbal medicinal plants, are rich in bioactive chemicals called flavonoids and their derivatives like Flavones, Anthocyanins, Iso-flavonoid, Flavanones, Flavanols, and Flavan-3-ols. Most recently occurred research on flavonoids has demonstrated that they can regulate hepatoprotective properties. This is because they are essential parts of pharmaceutical and nutraceutical products due to their hepatoprotective, antioxidative, and immune-modulating characteristics. However, the characteristics of their hepatoprotective impact remain unclear. The purpose of this comprehensive review is to survey the flavonoid structure and enriched sources for their hepatoprotective and antioxidant effects concerning liver toxicity or injury.