Pterostilbene alleviates polymicrobial sepsis-induced liver injury: Possible role of SIRT1 signaling

Pterostilbene ameliorates oxidative stress and neuronal apoptosis after intracerebral hemorrhage via the sirtuin 1-mediated Nrf2 pathway in vivo and in vitro

INTRODUCTION

Oxidative stress and neuroapoptosis are significant pathological processes that occur in response to intracerebral hemorrhage (ICH), however, the optimal therapeutic strategy to treat these responses remains unknown. Pterostilbene (PTE) influences neural cell survival in in the pathology of a number of neurological diseases, but the mechanisms underlying this influence at present are not clear. The objective of the present study was to examine the potential impact of PTE on mitigating oxidative stress and neuronal apoptosis following ICH, while also elucidating the potential underlying pathways.

MATERIAL & METHOD

For in vivo experimentation, male C57BL/6 mice were used to establish ICH models. Wet-to-dry weight ratios were utilized to assess the degree of cerebral edema in the context of PTE intervention. Behavioral experiments were conducted to evaluate neurological dysfunction and cognitive impairment, and hematoxylin and eosin staining was employed to observe histopathological changes in the brain. Furthermore, oxidative stress levels in hippocampal tissues were measured, and cell apoptosis was examined using TUNEL staining and western blotting techniques. In vitro experiments were conducted to evaluate the extent of oxidative stress and neural apoptosis after sirtuin 1 (SIRT1) siRNA treatment. Immunofluorescence cytochemistry was used to analyze the immunofluorescence colocalization of SIRT1 and NeuN.

RESULT

Mice that experienced ICH exhibited worsening neurological deterioration, increased oxidative stress and neuronal cell apoptosis. However, the addition of PTE was found to lessen these effects. Furthermore, PTE was found to activate the SIRT1-mediated Nrf2 pathway in mice with ICH. When SIRT1 was inhibited, levels of oxidative stress and neuronal apoptosis increased, even in the presence of PTE.

CONCLUSION

The present study provided evidence to indicate that PTE can suppress oxidative damage and neuronal apoptosis following ICH by activating the SIRT1/Nrf2 pathway.

Flaxseed Oil Alleviates PFOS-Induced Liver Injury by Regulating Hepatic Cholesterol Metabolism

Perfluorooctanesulfonate (PFOS) is a widespread, persistent environmental pollutant that exerts apparent liver toxicity. Flaxseed oil (FO), a dietary oil rich in α-linolenic acid, has been demonstrated to possess a diverse array of health benefits. However, whether FO protects against PFOS-induced liver injury and its underlying mechanisms remain unclear. C57/BL6 mice were orally treated with different concentrations of FO alone or in combination with 10 mg/kg of PFOS for 28 consecutive days. Blood and liver tissues were collected for proteomic, histopathological, biochemical, immunohistochemical, and molecular examinations. Results demonstrated that FO supplementation reduced PFOS-induced liver injury, as evidenced by a decrease in histopathological changes, serum transaminase (ALT and AST) levels, levels of oxidative stress, and inflammatory cytokine (TNF-α, IL-1β, and IL-6) levels. Proteomic analyses showed that differentially expressed proteins were enriched in cholesterol metabolic pathways when comparing the PFOS group to the FO supplementation groups. The expression of cholesterol metabolism-related proteins was also subsequently measured, revealing that FO supplementation decreased the protein expressions of SREBP2, HMGCR, and LDLR while increasing the expression of CYP7A1. This study demonstrates that FO can alleviate PFOS-induced hepatotoxicity by regulating hepatic cholesterol metabolism, indicating that FO may serve as an effective dietary intervention for preventing liver injury caused by PFOS.

Role of sirtuins in sepsis and sepsis-induced organ dysfunction: A review

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Sepsis causes a high mortality rate and current treatment focuses on supportive therapies but lacks specific therapeutic targets. Notably, sirtuins (SIRTs) shows potential clinical application in the treatment of sepsis. It has been demonstrated that SIRTs, the nicotinamide adenine dinucleotide+(NAD+)-dependent deacetylases that regulate key signaling pathways in eukaryotes and prokaryotes, are involved in a variety of biological processes. To date, seven mammalian yeast Sir2 homologs have been identified. SIRTs can regulate inflammation, oxidative stress, apoptosis, autophagy, and other pathways that play important roles in sepsis-induced organ dysfunction. However, the existing studies on SIRTs in sepsis are too scattered, and there is no relevant literature to integrate them. This review innovatively summarizes the different mechanisms of SIRTs in sepsis organ dysfunction according to the different systems, and focuses on SIRT agonists, inhibitors, and targeted drugs that have been proved to be effective in the treatment of sepsis, so as to integrate the clinical research and basic research closely. We searched PubMed for all literature related to SIRTs and sepsis since its inception using the following medical subject headings: sirtuins, SIRTs, and sepsis. Data on the mechanisms of SIRTs in sepsis-induced organ damage and their potential as targets for disease treatment were extracted.

Evaluation of the Efficacy of Ozone Therapy on Liver Tissue in the Treatment of Sepsis in Rats with Cecal Perforation

Background and Objectives: Sepsis and its related complications are associated with high morbidity and mortality, often leading to liver damage. Ozone, a molecule with anti-inflammatory and antioxidant properties, may offer protective effects. This study aimed to evaluate the therapeutic and protective impact of ozone on liver injury in a rat model of sepsis induced by cecal ligation and perforation (CLP). Material and Methods: A total of 36 rats were randomly divided into five groups: control (Group C), ozone (Group O), cecal ligation and perforation (Group CLP), ozone + cecal ligation and perforation (Group O+CLP), and cecal ligation and perforation + ozone (Group CLP+O). In the ozone groups, 4 mL of ozone (20 µ/mL) was injected intraperitoneally. Biochemical and histopathological parameters were evaluated in liver tissue samples obtained at the end of 24 h. Results: Polymorphonuclear leukocyte and monocyte infiltration and the total injury score were significantly reduced in the ozone-treated groups compared to the CLP group (p < 0.001). Tumor necrosis factor and interleukin 10 levels in the rat liver tissue were significantly reduced in the O+CLP and CLP+O groups compared to the CLP group, with the O+CLP group showing a more substantial decrease than the CLP+O group (p < 0.001). Thiobarbituric acid reactive substances and glutathione s-transferase levels were significantly lower in the ozone-treated groups compared to the CLP group (p < 0.001). Catalase activity was significantly elevated in the O+CLP group compared to the CLP group (p < 0.001). Serum aspartate transaminase, alanine transaminase, gamma-glutamyl transferase, and total bilirubin were significantly increased in the CLP group and decreased in the ozone-treated groups (p < 0.001, p < 0.001, p = 0.01, p < 0.001 respectively). Conclusions: Administering ozone to rats one hour before the CLP significantly mitigated liver damage, showing a more pronounced effect compared to administering ozone one hour after CLP. The results indicate that ozone could serve a protective function in managing sepsis-induced liver damage.

Sirtuin 1 in regulating the p53/glutathione peroxidase 4/gasdermin D axis in acute liver failure

In this editorial, we comment on the article by Zhou et al. The study reveals the connection between ferroptosis and pyroptosis and the effect of silent information regulator sirtuin 1 (SIRT1) activation in acute liver failure (ALF). ALF is characterized by a sudden and severe liver injury resulting in significant hepatocyte damage, often posing a high risk of mortality. The predominant form of hepatic cell death in ALF involves apoptosis, ferroptosis, autophagy, pyroptosis, and necroptosis. Glutathione peroxidase 4 (GPX4) inhibition sensitizes the cell to ferroptosis and triggers cell death, while Gasdermin D (GSDMD) is a mediator of pyroptosis. The study showed that ferroptosis and pyroptosis in ALF are regulated by blocking the p53/GPX4/GSDMD pathway, bridging the gap between the two processes. The inhibition of p53 elevates the levels of GPX4, reducing the levels of inflammatory and liver injury markers, ferroptotic events, and GSDMD-N protein levels. Reduced p53 expression and increased GPX4 on deletion of GSDMD indicated ferroptosis and pyroptosis interaction. SIRT1 is a NAD-dependent deacetylase, and its activation attenuates liver injury and inflammation, accompanied by reduced ferroptosis and pyroptosis-related proteins in ALF. SIRT1 activation also inhibits the p53/GPX4/GSDMD axis by inducing p53 acetylation, attenuating LPS/D-GalN-induced ALF.

Vincamine exerts hepato-protective activity during colon ligation puncture-induced sepsis by modulating oxidative stress, apoptosis, and TNFα/Nrf-2/Keap-1 signaling pathways

Sepsis is a pathological and biochemical disorder induced by numerous infections, leading to critical illness and a high mortality rate worldwide. Vincamine is an indole alkaloid compound obtained from the leaves of Vinca minor. The present study aims to investigate the hepato-protective activity of vincamine during colon ligation puncture (CLP)-induced sepsis at the molecular level. Sepsis was induced using the CLP model. Liver function enzymes such as ALT and AST were analyzed. The hepatic antioxidant status (SOD and GSH), lipid peroxidation (MDA), the pro-inflammatory cytokines (TNFα, IL-6, and IL-1β), bax, bcl2, and cleaved caspase 3 proteins were estimated. Nrf-2 and Keap-1 protein expression was evaluated using western blotting. Histopathological investigation of liver tissues was also performed. CLP-induced sepsis led to liver injury through the elevation of ALT and AST liver enzymes. Oxidative stress was initiated during CLP via the suppression of hepatic GSH content and SOD activity and the elevation of MDA. The inflammatory condition was activated by the upregulation of TNFα, IL-6, IL-1β, and Keap-1 and the downregulation of Nrf-2 proteins. The apoptosis was initiated through the activation of bax and cleaved caspase 3 protein expression and inhibition of bcl2 protein expression. However, vincamine significantly improved the hepatic histological abnormalities and decreased liver enzymes (ALT and AST). It ameliorated oxidative stress, as evidenced by reducing the hepatic MDA content and increasing the SOD activity and GSH content. Moreover, vincamine reduced the hepatic content of TNFα, IL-6, IL-1β, and Keap-1 and increased Nrf-2 protein expression. Additionally, it upregulated bcl2 protein expression and downregulated bax and cleaved caspase 3 protein expression. Vincamine exhibited hepato-protective potential during CLP-induced sepsis via the cross-connection of antioxidant, anti-inflammatory, and anti-apoptotic activities by modulating TNFα/IL-6/IL-1β/Nrf-2/Keap-1 and regulating bax/bcl2/cleaved caspase 3 signaling pathways.

Insights into the mechanism of action of pterostilbene against influenza A virus-induced acute lung injury

BACKGROUND

Severe respiratory system illness caused by influenza A virus infection is associated with excessive inflammation and abnormal apoptosis in alveolar epithelial cells (AEC). However, there are limited therapeutic options for influenza-associated lung inflammation and apoptosis. Pterostilbene (PTE, trans-3,5-dimethoxy-4-hydroxystilbene) is a dimethylated analog of resveratrol that has been reported to limit influenza A virus infection by promoting antiviral innate immunity, but has not been studied for its protective effects on virus-associated inflammation and injury in AEC.

PURPOSE

Our study aimed to investigate the protective effects and underlying mechanisms of PTE in modulating inflammation and apoptosis in AEC, as well as its effects on macrophage polarization during influenza virus infection.

STUDY DESIGN AND METHODS

A murine model of influenza A virus-mediated acute lung injury was established by intranasal inoculation with 5LD50 of mouse-adapted H1N1 viruses. Hematoxylin and eosin staining, immunofluorescence, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, western blotting, Luminex and flow cytometry were performed.

RESULTS

PTE effectively mitigated lung histopathological changes and injury induced by H1N1 viruses in vivo. These beneficial effects of PTE were attributed to the suppression of inflammation and apoptosis in AEC, as well as the modulation of M1 macrophage polarization. Mechanistic investigations revealed that PTE activated the phosphorylated AMP-activated protein kinase alpha (P-AMPKα)/sirtui1 (Sirt1)/PPARγ coactivator 1-alpha (PGC1α) signal axis, leading to the inhibition of nuclear factor kappa-B (NF-κB) and p38 mitogen-activated protein kinase (MAPK) signaling induced by H1N1 viruses, thereby attenuating inflammation and apoptosis in AEC. PTE also forced activation of the P-AMPKα/Sirt1/PGC1α signal axis in RAW264.7 cells, counteracting the activation of phosphorylated signal transducer and activator of transcription 1 (P-STAT1) induced by H1N1 viruses and the augment of P-STAT1 activation in RAW264.7 cells with interferon-gamma (IFN-γ) pretreatment before viral infection, thereby reducing H1N1 virus-mediated M1 macrophage polarization as well as the enhancement of macrophages into M1 phenotypes elicited by IFN-γ pretreatment. Additionally, the promotion of the transition of macrophages towards the M2 phenotype by PTE was also related to activation of the P-AMPKα/Sirt1/PGC1α signal axis. Moreover, co-culturing non-infected AEC with H1N1 virus-infected RAW264.7 cells in the presence of PTE inhibited apoptosis and tight junction disruption, which was attributed to the suppression of pro-inflammatory mediators and pro-apoptotic factors in an AMPKα-dependent manner.

CONCLUSION

In conclusion, our findings suggest that PTE may serve as a promising novel therapeutic option for treating influenza-associated lung injury. Its ability to suppress inflammation and apoptosis in AEC, modulate macrophage polarization, and preserve alveolar epithelial cell integrity highlights its potential as a therapeutic agent in influenza diseases.

Investigating the role of itaconate in macrophage activation and oxidative stress injury in sepsis-associated acute kidney injury

BACKGROUND

Sepsis may be linked to oxidative stress and can be controlled by itaconate, an activator of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Nevertheless, the itaconate impact on sepsis-associated acute kidney injury (SA-AKI) has yet to be definitively established.

METHODS

We employed SA-AKI mouse model through a cecal ligation and puncture (CLP) procedure for the in vivo investigation of the potential nephroprotective effect of itaconate in this study. A plasmid was transfected into RAW264.7 cells to examine the Nrf2 pathway function after itaconate administration. Finally, the immune-responsive gene 1-knockout (IRG1-/-) mice were used to study the itaconate impacts on oxidative stress-induced SA-AKI.

RESULTS

We have shown that 4-octyl itaconate (OI) significantly reduced CD11b-positive macrophage aggregation and activated the Nrf2 pathway in the bone marrow-derived macrophages (BMDM). The impacts of Nrf2 inhibitor ML385 on the anti-inflammatory and antioxidant properties of itaconate were found to be partial. OI inhibited lipopolysaccharide-induced oxidative stress injury in RAW264.7 macrophages and activated Nrf2 in the nucleus to hinder the expression of nuclear factor kappa B p65, thereby suppressing oxidative stress injury in the macrophages. Additionally, the introduction of the transfected plasmid resulted in a partial inhibition of the anti-inflammatory impact of itaconate. The kidney injury caused by sepsis exhibited greater severity in the IRG1-/- mice than in the wild type mice. Exogenous OI partially attenuated the kidney injury induced by sepsis in the IRG1-/- mice and suppressed the oxidative stress injury in macrophages.

CONCLUSIONS

This investigation offers new proof to support the itaconate function in the development and progression of SA-AKI and shows a new possible therapeutic agent for the SA-AKI treatment.

The role and therapeutic potential of SIRTs in sepsis

Sepsis is a life-threatening organ dysfunction caused by the host's dysfunctional response to infection. Abnormal activation of the immune system and disturbance of energy metabolism play a key role in the development of sepsis. In recent years, the Sirtuins (SIRTs) family has been found to play an important role in the pathogenesis of sepsis. SIRTs, as a class of histone deacetylases (HDACs), are widely involved in cellular inflammation regulation, energy metabolism and oxidative stress. The effects of SIRTs on immune cells are mainly reflected in the regulation of inflammatory pathways. This regulation helps balance the inflammatory response and may lessen cell damage and organ dysfunction in sepsis. In terms of energy metabolism, SIRTs can play a role in immunophenotypic transformation by regulating cell metabolism, improve mitochondrial function, increase energy production, and maintain cell energy balance. SIRTs also regulate the production of reactive oxygen species (ROS), protecting cells from oxidative stress damage by activating antioxidant defense pathways and maintaining a balance between oxidants and reducing agents. Current studies have shown that several potential drugs, such as Resveratrol and melatonin, can enhance the activity of SIRT. It can help to reduce inflammatory response, improve energy metabolism and reduce oxidative stress, showing potential clinical application prospects for the treatment of sepsis. This review focuses on the regulation of SIRT on inflammatory response, energy metabolism and oxidative stress of immune cells, as well as its important influence on multiple organ dysfunction in sepsis, and discusses and summarizes the effects of related drugs and compounds on reducing multiple organ damage in sepsis through the pathway involving SIRTs. SIRTs may become a new target for the treatment of sepsis and its resulting organ dysfunction, providing new ideas and possibilities for the treatment of this life-threatening disease.

The role of sirtuin1 in liver injury: molecular mechanisms and novel therapeutic target

Liver disease is a common and serious threat to human health. The progression of liver diseases is influenced by many physiologic processes, including oxidative stress, inflammation, bile acid metabolism, and autophagy. Various factors lead to the dysfunction of these processes and basing on the different pathogeny, pathology, clinical manifestation, and pathogenesis, liver diseases are grouped into different categories. Specifically, Sirtuin1 (SIRT1), a member of the sirtuin protein family, has been extensively studied in the context of liver injury in recent years and are confirmed the significant role in liver disease. SIRT1 has been found to play a critical role in regulating key processes in liver injury. Further, SIRT1 seems to cause divers outcomes in different types of liver diseases. Recent studies have showed some therapeutic strategies involving modulating SIRT1, which may bring a novel therapeutic target. To elucidate the mechanisms underlying the role of sirtuin1 in liver injury and its potentiality as a therapeutic target, this review outlines the key signaling pathways associated with sirtuin1 and liver injury, and discusses recent advances in therapeutic strategies targeting sirtuin1 in liver diseases.

Silent information regulator sirtuin 1 ameliorates acute liver failure via the p53/glutathione peroxidase 4/gasdermin D axis

BACKGROUND

Acute liver failure (ALF) has a high mortality with widespread hepatocyte death involving ferroptosis and pyroptosis. The silent information regulator sirtuin 1 (SIRT1)-mediated deacetylation affects multiple biological processes, including cellular senescence, apoptosis, sugar and lipid metabolism, oxidative stress, and inflammation.

AIM

To investigate the association between ferroptosis and pyroptosis and the upstream regulatory mechanisms.

METHODS

This study included 30 patients with ALF and 30 healthy individuals who underwent serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) testing. C57BL/6 mice were also intraperitoneally pretreated with SIRT1, p53, or glutathione peroxidase 4 (GPX4) inducers and inhibitors and injected with lipopolysaccharide (LPS)/D-galactosamine (D-GalN) to induce ALF. Gasdermin D (GSDMD)-/- mice were used as an experimental group. Histological changes in liver tissue were monitored by hematoxylin and eosin staining. ALT, AST, glutathione, reactive oxygen species, and iron levels were measured using commercial kits. Ferroptosis- and pyroptosis-related protein and mRNA expression was detected by western blot and quantitative real-time polymerase chain reaction. SIRT1, p53, and GSDMD were assessed by immunofluorescence analysis.

RESULTS

Serum AST and ALT levels were elevated in patients with ALF. SIRT1, solute carrier family 7a member 11 (SLC7A11), and GPX4 protein expression was decreased and acetylated p5, p53, GSDMD, and acyl-CoA synthetase long-chain family member 4 (ACSL4) protein levels were elevated in human ALF liver tissue. In the p53 and ferroptosis inhibitor-treated and GSDMD-/- groups, serum interleukin (IL)-1β, tumour necrosis factor alpha, IL-6, IL-2 and C-C motif ligand 2 levels were decreased and hepatic impairment was mitigated. In mice with GSDMD knockout, p53 was reduced, GPX4 was increased, and ferroptotic events (depletion of SLC7A11, elevation of ACSL4, and iron accumulation) were detected. In vitro, knockdown of p53 and overexpression of GPX4 reduced AST and ALT levels, the cytostatic rate, and GSDMD expression, restoring SLC7A11 depletion. Moreover, SIRT1 agonist and overexpression of SIRT1 alleviated acute liver injury and decreased iron deposition compared with results in the model group, accompanied by reduced p53, GSDMD, and ACSL4, and increased SLC7A11 and GPX4. Inactivation of SIRT1 exacerbated ferroptotic and pyroptotic cell death and aggravated liver injury in LPS/D-GalN-induced in vitro and in vivo models.

CONCLUSION

SIRT1 activation attenuates LPS/D-GalN-induced ferroptosis and pyroptosis by inhibiting the p53/GPX4/GSDMD signaling pathway in ALF.

Albiflorin Alleviates Sepsis-induced Acute Liver Injury through mTOR/p70S6K Pathway

BACKGROUND

Sepsis often induces hepatic dysfunction and inflammation, accounting for a significant increase in the incidence and mortality rates. To this end, albiflorin (AF) has garnered enormous interest due to its potent anti-inflammatory activity. However, the substantial effect of AF on sepsis-mediated acute liver injury (ALI), along with its potential mechanism of action, remains to be explored.

METHODS

An LPS-mediated primary hepatocyte injury cell model in vitro and a mouse model of CLP-mediated sepsis in vivo were initially built to explore the effect of AF on sepsis. Furthermore, the hepatocyte proliferation by CCK-8 assay in vitro and animal survival analyses in vivo for the survival time of mice were carried out to determine an appropriate concentration of AF. Then, flow cytometry, Western blot (WB), and TUNEL staining analyses were performed to investigate the effect of AF on the apoptosis of hepatocytes. Moreover, the expressions of various inflammatory factors by ELISA and RT-qPCR analyses and oxidative stress by ROS, MDA, and SOD assays were determined. Finally, the potential mechanism of AF alleviating the sepsis-mediated ALI via the mTOR/p70S6K pathway was explored through WB analysis.

RESULTS

AF treatment showed a significant increase in the viability of LPS-inhibited mouse primary hepatocytes cells. Moreover, the animal survival analyses of the CLP model mice group indicated a shorter survival time than the CLP+AF group. AF-treated groups showed significantly decreased hepatocyte apoptosis, inflammatory factors, and oxidative stress. Finally, AF exerted an effect by suppressing the mTOR/p70S6K pathway.

CONCLUSION

In summary, these findings demonstrated that AF could effectively alleviate sepsis-mediated ALI via the mTOR/p70S6K signaling pathway.

Unlocking the therapeutic potential of natural stilbene: Exploring pterostilbene as a powerful ally against aging and cognitive decline

The therapeutic potential of natural stilbenes, with a particular focus on pterostilbene (PTE), has emerged as a promising avenue of research targeting age-associated conditions encompassing cardiovascular diseases (CVD), diabetes mellitus (DM), and cognitive decline. This comprehensive investigation delves into the intricate mechanisms through which PTE, a polyphenolic compound abundant in grapes and blueberries, exerts its advantageous effects as an anti-aging agent. Central to its action is the modulation of hallmark aging processes, including oxidative damage, inflammatory responses, telomere attrition, and cellular senescence. PTE's ability to effectively penetrate the blood-brain barrier amplifies its potential for safeguarding neural health, thereby facilitating the regulation of neuronal signalling cascades, synaptic plasticity, and mitochondrial functionality. Through engagement with sirtuin proteins, it orchestrates cellular resilience, longevity, and metabolic equilibrium. Encouraging findings from preclinical studies portray PTE as a robust candidate for counteracting age-linked cognitive decline, augmenting memory consolidation, and potentially ameliorating neurodegenerative maladies such as Alzheimer's disease (AD). The synthesis of current scientific insights accentuates the promising translational prospects of PTE as a potent, naturally derived therapeutic agent against cognitive impairments associated with aging. Consequently, these collective findings lay a solid groundwork for forthcoming clinical inquiries and innovative therapeutic interventions in this realm.

Rebastinib attenuates liver injury following cecal ligation and puncture in male mice

Sepsis remains a public health issue with high morbidity and mortality. Liver injury due to sepsis is associated with poor outcomes and an increased risk of death among septic patients. Rebastinib is a small molecule inhibiting the Tie2 receptor and vascular endothelial growth factor receptor-2 (VEGFR2). The current study aimed to reveal the potential protective impact of Rebastinib against sepsis-induced liver injury. Twenty-four adult male mice were allocated into four groups (six per group) as follows: Sham group was exposed to anesthesia and laparotomy with no cecal ligation and puncture procedure (CLP); CLP group was subjected CLP procedure; vehicle-treated group was pretreated with vehicle (oral route) one hour prior to CLP procedure; Rebastinib group was pretreated with oral Rebastinib one hour before induction of CLP. Collected blood was used to measure the serum levels of AST, ALT, and angiopoietin 2. Homogenized liver tissues were used to investigate IL-6, TNF-α, ICAM-1, MIF, VEGF, F2-isoprostanes, and caspase-11 levels. Histological examination was used to determine the severity of liver damage. Compared to the sham group, mice subjected to CLP had high levels of these biomarkers with a high degree of liver injury. In contrast, Rebastinib markedly reduced these levels and mitigated the liver damage. Rebastinib may be a hepatoprotective agent against sepsis-associated liver injury.

A comprehensive insight into the molecular and cellular mechanisms of action of resveratrol on complications of sepsis a systematic review

Sepsis and septic shock are still one of the most important medical challenges. Sepsis is an extreme and uncontrolled response of the innate immune system to invading pathogenesis. Resveratrol (3,5,4'-trihydroxytrans-stilbene), is a phenolic and non-flavonoid compound naturally produced by some plants and fruits. The object of the current study is to systematically review the impacts of resveratrol and its mechanisms of function in the management of sepsis and its related complications. The guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statements were applied to perform the study (PROSPERO: CRD42021289357). We searched Embase, Web of Science, Google Scholar, Science Direct, PubMed, ProQuest, and Scopus databases up to January 2023 by using the relevant keywords. Study criteria were met by 72 out of 1415 articles screened. The results of this systematic review depict that resveratrol can reduces the complications of sepsis by affecting inflammatory pathways, oxidative stress, and modulating immune responses. Future human randomized clinical trials are necessary due to the promising therapeutic effects of resveratrol on sepsis complications and the lack of clinical trials in this regard.

Induction of Sestrin2 by pterostilbene suppresses ethanol-triggered hepatocyte senescence by degrading CCN1 via p62-dependent selective autophagy

Hepatocyte senescence is a key event participating in the progression of alcoholic liver disease. Autophagy is a critical biological process that controls cell fates by affecting cell behaviors like senescence. Pterostilbene is a natural compound with hepatoprotective potential; however, its implication for alcoholic liver disease was not understood. This study was aimed to investigate the therapeutic effect of pterostilbene on alcoholic liver disease and elucidate the potential mechanism. Our results showed that pterostilbene alleviated ethanol-triggered hepatocyte damage and senescence. Intriguingly, pterostilbene decreased the protein abundance of cellular communication network factor 1 (CCN1) in ethanol-exposed hepatocytes, which was essential for pterostilbene to execute its anti-senescent function. In vivo studies verified the anti-senescent effect of pterostilbene on hepatocytes of alcohol-intoxicated mice. Pterostilbene also relieved senescence-associated secretory phenotype (SASP), redox imbalance, and steatosis by suppressing hepatic CCN1 expression. Mechanistically, pterostilbene-forced CCN1 reduction was dependent on posttranscriptional regulation via autophagy machinery but not transcriptional regulation. To be specific, pterostilbene restored autophagic flux in damaged hepatocytes and activated p62-mediated selective autophagy to recognize and lead CCN1 to autolysosomes for degradation. The protein abundance of Sestrin2 (SESN2), a core upstream modulator of autophagy pathway, was decreased in ethanol-administrated hepatocytes but rescued by co-treatment with pterostilbene. Induction of SESN2 protein by pterostilbene rescued ethanol-triggered autophagic dysfunction in hepatocytes, which then reduced senescence-associated markers, postponed hepatocyte senescence, and relieved alcohol-caused liver injury and inflammation. In conclusion, this work discovered a novel compound pterostilbene with therapeutic implications for alcoholic liver disease and uncover its underlying mechanism.

Pterostilbene alleviated NAFLD via AMPK/mTOR signaling pathways and autophagy by promoting Nrf2

BACKGROUND

NAFLD is a liver disease that is caused by liver damage or extreme lipid deposition but not alcohol. Nrf2 could mediate resistance to oxidative stress injury. Autophagy can degrade metabolic waste and accumulated toxic endogenous substances. Pterostilbene (PTE) is an active compound extracted from blueberry, and grape, that exhibits many biological effects, such as antiinflammation and antitumor.

PURPOSE

This study provides a mechanism of PTE affecting on oxidative stress and autophagy in NAFLD mice. Tyloxapol, oil acid (OA) and palmitic acid (PA) were used to induce lipid accumulation in mice and HepG2 cells.

METHODS

Western blotting, CRISPR/Cas 9 and other molecular biological approaches were applied to explore the mechanisms of PTE effected on NAFLD.

RESULTS

PTE pretreatment effectively reduced the lipid accumulation in OA and PA induced HepG2 cells and tyloxapol induced mice, and significantly promoted the expression of nNrf2, PPAR-α and HO-1, and AMPK activity, but inhibited the expression of mTORC 1 and SREBP-1c. PTE activated phosphatidylinositide 3-kinase (PI3K) and proteins in the autophagy-related gene (ATG) family, and promoted the transformation of LC3Ⅰ to LC3Ⅱ which indicated the activation of autophagy, however, these effects were abolished after Nrf2 knockout.

CONCLUSION

PTE effectively alleviated oxidative stress damage induced by excessive lipid accumulation in hepatocytes, thus promoting the metabolism and decomposition of fatty acids to improve NAFLD.

Pterostilbene Ameliorates Fumonisin B1-Induced Cytotoxic Effect by Interfering in the Activation of JAK/STAT Pathway

Fumonisin B1 (FB1) is a mycotoxin that poses a great threat to agricultural production and the health of humans and animals. Pterostilbene (PTE) is a natural plant polyphenolic compound with good anti-inflammatory, antioxidant and cell regeneration effects, yet its effectiveness in treating FB1-induced cytotoxicity remains to be explored. In this study, we used porcine alveolar macrophages (3D4/21) as a model to characterize the cytotoxicity induced by FB1, and to investigate the potential alleviating effect of PTE on FB1-induced cytotoxicity. We demonstrate that FB1 induces cytotoxicity, apoptosis, pro-inflammatory cytokine production and mitochondrial damage, which can be largely recovered by PTE treatment, suggesting the promising application of PTE to treat FB1-induced damage. Mechanistically, FB1 activates the JAK/STAT signaling pathway, while PTE attenuates FB1-induced cytotoxicity through the inhibition of key JAK/STAT genes such as JAK2 and STAT3. Overall, our study characterized the molecular mechanism for FB1-induced cytotoxicity and found PTE to be a promising component which can alleviate FB1-induced cytotoxicity by interfering in the activation of JAK/STAT pathway.

Alpha-Chymotrypsin Protects Against Acute Lung, Kidney, and Liver Injuries and Increases Survival in CLP-Induced Sepsis in Rats Through Inhibition of TLR4/NF-κB Pathway

Abstract

Inflammation and oxidative stress play a major role in the development of sepsis and its associated complications, leading to multiple organ failure and death. The lungs, liver, and kidneys are among the early affected organs correlated with mortality in sepsis. Alpha-chymotrypsin (α-ch) is a serine protease that exerts anti-inflammatory, anti-edematous, and anti-oxidant properties.

Purpose

This study was undertaken to elucidate if the anti-inflammatory and anti-oxidant effects of α-ch observed in previous studies can alleviate lung, liver, and kidney injuries in a cecal ligation and puncture (CLP)-induced sepsis model, and thus decrease mortality.

Materials and Methods

Septic animals were given α-ch 2 h post CLP procedure. Sepsis outcomes were assessed in the lungs, liver, and kidneys. Separate animal groups were investigated for a survival study.

Results

CLP resulted in 0% survival, while α-chymotrypsin post-treatment led to 50% survival at the end of the study. Administration of α-chymotrypsin resulted in a significant attenuation of sepsis-induced elevated malonaldehyde (MDA) and total nitrite/nitrate (NOx) levels. In addition, there was a significant increase in reduced glutathione (GSH) content and superoxide dismutase (SOD) activity in the lungs, liver, and kidneys. Administration of α-ch reduced elevated tissue expression of toll-like receptor-4 (TLR4), nuclear factor kappa-B (NF-κB), myeloperoxidase (MPO), and inducible nitric oxide synthase (iNOS). Alpha-chymotrypsin resulted in a significant reduction in serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6). Alpha-chymotrypsin attenuated the rise in serum creatinine, cystatin C, blood urea nitrogen (BUN), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels that was observed in the septic group. In addition, α-ch significantly reduced the lung wet/dry weight ratio, total protein content, and leukocytic counts in bronchoalveolar lavage fluid (BALF). Histopathological examination of the lungs, liver, and kidneys confirmed the protective effects of α-ch on those organs.

Conclusion

α-ch has protective potential against sepsis through lowering tissue expression of TLR4, NF-κB, MPO, and iNOS leading to decreased oxidative stress and inflammatory signals induced by sepsis. This effect appeared to alleviate the damage to the lungs, liver, and kidneys and increase survival in rats subjected to sepsis.

Protective effects of menthol against sepsis-induced hepatic injury: Role of mediators of hepatic inflammation, apoptosis, and regeneration

Liver dysfunction in sepsis is a major complication that amplifies multiple organ failure and increases the risk of death. Inflammation and oxidative stress are the main mediators in the pathophysiology of sepsis. Therefore, we investigated the role of menthol, a natural antioxidant, against sepsis-induced liver injury in female Wistar rats. Sepsis was induced by cecal ligation and puncture (CLP). Menthol (100 mg/kg) was given intragastric 2 h after CLP. Blood samples and liver tissues were collected 24 h after surgery. Menthol significantly (p < 0.05) attenuated the sepsis-induced elevation in serum liver enzymes and improved the hepatic histopathological changes. Menthol treatment significantly (p < 0.05) decreased hepatic levels of tumor necrosis factor-alpha, malondialdehyde, total nitrite, and cleaved caspase-3. It restored the hepatic levels of superoxide dismutase and reduced glutathione. Additionally, menthol significantly (p < 0.05) increased hepatic levels of B-cell lymphoma 2 (Bcl-2); an anti-apoptotic factor, and proliferating cell nuclear antigen (PCNA), a biomarker of regeneration and survival. Our results showed the therapeutic potential of menthol against liver injury induced by sepsis.

Pharmacological Approaches to Decelerate Aging: A Promising Path

Biological aging or senescence is a course in which cellular function decreases over a period of time and is a consequence of altered signaling mechanisms that are triggered in stressed cells leading to cell damage. Aging is among the principal risk factors for many chronic illnesses such as cancer, cardiovascular disorders, and neurodegenerative diseases. Taking this into account, targeting fundamental aging mechanisms therapeutically may effectively impact numerous chronic illnesses. Selecting ideal therapeutic options in order to hinder the process of aging and decelerate the progression of age-related diseases is valuable. Along therapeutic options, life style modifications may well render the process of aging. The process of aging is affected by alteration in many cellular and signaling pathways amid which mTOR, SIRT1, and AMPK pathways are the most emphasized. Herein, we have discussed the mechanisms of aging focusing mainly on the mentioned pathways as well as the role of inflammation and autophagy in aging. Moreover, drugs and natural products with antiaging properties are discussed in detail.

Effect of Celecoxib and Infliximab against Multiple Organ Damage Induced by Sepsis in Rats: A Comparative Study

In cases of sepsis, the immune system responds with an uncontrolled release of proinflammatory cytokines and reactive oxygen species. The lungs, kidneys, and liver are among the early impacted organs during sepsis and are a direct cause of mortality. The aim of this study was to compare the effects of infliximab (IFX) and celecoxib (CLX) on septic rats that went through a cecal ligation and puncture (CLP) surgery to induce sepsis. This study included four groups: sham, CLP (untreated), and CLP-treated with CLX or IFX. The administration of “low dose” CLX or IFX was performed after 2 h following the induction of sepsis. Twenty-four hours following the induction of sepsis, the rats were sacrificed and blood samples were collected to evaluate kidney, liver, and lung injuries. MDA and NOx content, in addition to SOD activity and GSH levels, were evaluated in the tissue homogenates of each group. Tissue samples were also investigated histopathologically. In a separate experiment, the same groups were employed to evaluate the survival of septic rats in a 7-day observation period. The results of this study showed that treatment with either CLX or IFX ameliorated the three organs’ damage compared to septic-untreated rats, decreased oxidative stress, enhanced the antioxidant defense, and reduced serum cytokines. As a result, a higher survival rate resulted: 62.5% and 37.5% after the administration of CLX and IFX, respectively, compared to 0% in the CLP group after 7 days. No significant differences were observed between the two agents in all measured parameters. Histopathological examination confirmed the observed results. In conclusion, CLX and IFX ameliorated lung, kidney, and liver injuries associated with sepsis through anti-inflammatory and antioxidant actions, which correlated to the increase in survival observed with both of them.

Intravenous nicotinamide riboside elevates mouse skeletal muscle NAD+ without impacting respiratory capacity or insulin sensitivity

In clinical trials, oral supplementation with nicotinamide riboside (NR) fails to increase muscle mitochondrial respiratory capacity and insulin sensitivity but also does not increase muscle NAD⁺ levels. This study tests the feasibility of chronically elevating skeletal muscle NAD⁺ in mice and investigates the putative effects on mitochondrial respiratory capacity, insulin sensitivity, and gene expression. Accordingly, to improve bioavailability to skeletal muscle, we developed an experimental model for administering NR repeatedly through a jugular vein catheter. Mice on a Western diet were treated with various combinations of NR, pterostilbene (PT), and voluntary wheel running, but the metabolic effects of NR and PT treatment were modest. We conclude that the chronic elevation of skeletal muscle NAD⁺ by the intravenous injection of NR is possible but does not affect muscle respiratory capacity or insulin sensitivity in either sedentary or physically active mice. Our data have implications for NAD⁺ precursor supplementation regimens.

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A model was developed for daily intravenous NR injections

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Intravenous NR stably elevates NAD⁺ of skeletal muscle and adipose, but not liver

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Voluntary running and intravenous NR synergize to boost mouse skeletal muscle NAD⁺

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NR did not impact skeletal muscle insulin sensitivity or respiratory capacity

Ginsenoside Rg3 alleviates septic liver injury by regulating the lncRNA TUG1/miR-200c-3p/SIRT1 axis

Background

Studies have shown that ginsenoside R3 (Rg3) plays a protective role in sepsis-induced organ injuries and mitochondrial dysfunction. Long noncoding RNA (lncRNA) taurine-upregulated gene 1 (TUG1) is regarded as a regulator in sepsis. However, the association between TUG1 and Rg3 remains elusive.

Methods

A sepsis mouse model was established by caecal ligation and puncture (CLP), and liver injury was induced by haematoxylin-eosin (H&E) staining. Lipopolysaccharide (LPS) was used to induce hepatocyte damage. The expression levels of TUG1, microRNA (miR)-200a-3p, and silencing information regulator 1 (SIRT1) were examined by quantitative real-time polymerase chain reaction (qRT–PCR) assays. Cell viability was monitored using the Cell Counting Kit-8 (CCK-8) assay. MitoSOX Red staining and CBIC2 (JC-1) dye were employed to detect mitochondrial reactive oxygen species (ROS) and mitochondrial transmembrane potential (MTP) levels, respectively. The interaction between miR-200a-3p and TUG1 or SIRT1 was confirmed via dual-luciferase reporter or RNA immunoprecipitation (RIP) assay.

Results

Rg3 upregulated TUG1 expression in liver tissues of CLP mice and LPS-induced hepatocytes. Rg3 could activate autophagy to improve mitochondrial dysfunction in LPS-treated hepatocytes, which was partially reversed by TUG1 depletion or miR-200a-3p overexpression. Importantly, TUG1 targeted miR-200a-3p to activate the SIRT1/AMP-activated protein kinase (AMPK) pathway in LPS-treated hepatocytes. Moreover, gain of TUG1 ameliorated mitochondrial dysfunction in LPS-treated hepatocytes by sequestering miR-200a-3p.

Conclusion

Our study revealed that Rg3 increased TUG1 expression and reduced miR-200a-3p expression to stimulate the SIRT1/AMPK pathway, thereby enhancing autophagy to improve sepsis-induced liver injury and mitochondrial dysfunction.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12950-021-00296-2.

Resveratrol alleviates acute lung injury through regulating PLSCR-3-mediated mitochondrial dysfunction and mitophagy in a cecal ligation and puncture model

Sepsis is considered as a life-threatening organ dysfunction caused by a dysregulated response of the host to an infection. Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a life-threatening condition, and is the type of organ injury that is most commonly induced by sepsis. Resveratrol (RSV) has been shown to exert a wide range of therapeutic effects due to its anti-inflammatory and anti-oxidant properties. The present study aimed to investigate whether RSV could mitigate sepsis-induced ALI/ARDS, and also to unravel the underlying mechanism. The model of sepsis was established by applying the cecal ligation and puncture (CLP) method, and mitochondria from the lung tissue were isolated to assess mitochondrial function, as determined from measuring mitochondrial superoxide production using MitoSOX red mitochondrial superoxide indicator and the membrane potential. It was found that RSV could exert a protective role in CLP-induced ALI/ARDS, as evidenced by moderate levels of inflammatory cell infiltration and interstitial edema, as well as decreased levels of C-reactive protein (P<0.01), interleukin (IL)-6 (P<0.01), IL-1β (P<0.01) and tumor necrosis factor-α (P<0.01). Moreover, phospholipid scramblase 3 (PLSCR-3)-mediated mitochondrial dysfunction and mitophagy were shown to contribute towards the CLP-caused lung damage, which was reversed upon RSV administration, as demonstrated by improved mitochondrial function and markedly reduced increases in the protein levels of autophagy related (ATG)5 (P<0.01), ATG7 (P<0.05) and microtubule-associated protein 1A/1B-light chain 3 (LC3-Ⅰ/Ⅱ) (P<0.01), and a significantly increased expression of P62 (P<0.05). In addition, with regard to the CLP-induced lung injury in the mouse model, overexpression of PLSCR-3 was found to remove the beneficial effects observed upon RSV treatment. Taken together, the results of the present study have uncovered a novel molecular mechanism through which RSV may alleviate ALI/ARDS via regulating PLSCR-3-mediated mitochondrial dysfunction and mitophagy in CLP-induced mouse model.

Pterostilbene Alleviates Cholestasis by Promoting SIRT1 Activity in Hepatocytes and Macrophages

Background and purpose: FXR is a promising target for the treatment of human cholestatic liver disease (CLD). SIRT1 is a deacetylase which promotes FXR activity through deacetylating FXR. Pterostilbene (PTE) is an activator of SIRT1. However, the role of PTE in cholestasis has so far not been investigated. We examined whether PTE treatment alleviate liver injury in DDC or ANIT-induced experimental cholestasis, and explored the underlying mechanisms. Experimental approach: Mice with DDC- or ANIT-induced cholestasis were treated with different dose of PTE. Primary hepatocytes and bone marrow derived macrophages were used in vitro to assess the molecular mechanism by which PTE may improve CLD. Identical doses of UDCA or PTE were administered to DDC- or ANIT-induced cholestasis mice. Key results: PTE intervention attenuated DDC or ANIT-induced cholestasis. PTE inhibited macrophage infiltration and activation in mouse liver through the SIRT1-p53 signaling pathway, and it improved hepatic bile metabolism through the SIRT1-FXR signaling pathway. Compare with UDCA, the same doses of PTE was more effective in improving cholestatic liver injury caused by DDC or ANIT. Conclusion and implications: SIRT1 activation in macrophages may be an effective CLD treatment avenue. Using CLD models, we thus identified PTE as a novel clinical candidate compound for the treatment of CLD.

Granisetron attenuates liver injury and inflammation in a rat model of cecal ligation and puncture-induced sepsis

BACKGROUND AND AIMS

Sepsis induced liver injury is recognized as a serious complication in intensive care units, it is deeply associated with oxidative stress, inflammation and subsequent pyroptosis. Hepatic pyroptosis known to aggravate sepsis-induced liver injury. Previous studies proved that granisetron has anti-inflammatory and antioxidant properties. Accordingly, this study aimed to evaluate the efficacy of granisetron on sepsis-induced liver damage using a cecal ligation and puncture (CLP) model in rats.

MAIN METHODS

Male albino rats were randomly divided into four groups: a sham control group, a granisetron control group, a CLP-induced sepsis group and a granisetron-treated CLP group. Markers of oxidative stress, inflammation, pyroptosis-related proteins and liver function were measured in addition to the histopathological study.

KEY FINDINGS

Granisetron pretreatment significantly decreased mortality and improved liver function, as indicated by decreased ALT, AST, and total bilirubin and increased albumin content. Moreover, granisetron increased GPx activity and downregulated hepatic MDA. Furthermore, granisetron administration significantly reduced TNF-α, IL-6, HMGB1 and NF-κB. It also decreased the expression of receptor for advanced glycation end and TLR4 in the liver tissue. Interestingly, granisetron inhibited pyroptosis as it reduced NLRP3, IL-1β and caspase-1. Granisetron was shown to increase Nrf2 and HO-1. In addition, granisetron treatment repaired, to some extent, the abnormal architecture of hepatic tissue.

SIGNIFICANCE

Our results suggested that granisetron is a potential therapeutic agent for sepsis-associated liver injury, possibly acting by inhibiting oxidative stress, inflammation and subsequent pyroptosis.

Recent Advances in Health Benefits of Stilbenoids

Biological targeting or molecular targeting is the main strategy in drug development and disease prevention. However, the problem of "off-targets" cannot be neglected. Naturally derived drugs are preferred over synthetic compounds in pharmaceutical markets, and the main goals are high effectiveness, lower cost, and fewer side effects. Single-target drug binding may be the major cause of failure, as the pathogenesis of diseases is predominantly multifactorial. Naturally derived drugs are advantageous because they are expected to have multitarget effects, but not off-targets, in disease prevention or therapeutic actions. The capability of phytochemicals to modulate molecular signals in numerous diseases has been widely discussed. Among them, stilbenoids, especially resveratrol, have been well-studied, along with their potential molecular targets, including AMPK, Sirt1, NF-κB, PKC, Nrf2, and PPARs. The analogues of resveratrol, pterostilbene, and hydroxylated-pterostilbene may have similar, if not more, potential biological targeting effects compared with their original counterpart. Furthermore, new targets that have been discussed in recent studies are reviewed in this paper.

Pterostilbene attenuates RIPK3-dependent hepatocyte necroptosis in alcoholic liver disease via SIRT2-mediated NFATc4 deacetylation

Receptor-interacting protein kinase (RIPK) 3-dependent necroptosis plays a critical role in alcoholic liver disease. RIPK3 also facilitates steatosis, oxidative stress, and inflammation. Pterostilbene (PTS) has favorable hepatoprotective activities. The present study was aimed to reveal the therapeutic effects of PTS on ethanol-induced hepatocyte necroptosis and further illustrate possible molecular mechanisms. Human hepatocytes LO2 were incubated with 100 mM ethanol for 24 h to mimic alcoholic hepatocyte injury. Results showed that PTS at 20 μM reduced damage-associated molecular patterns (DAMPs) release, including IL-1α and high-mobility group box 1 (HMGB1), and blocked necroptotic signaling, evidenced by decreased RIPK1 and RIPK3 expression. Trypan blue staining visually showed that PTS reduced nonviable hepatocytes after ethanol exposure, which was counteracted by adenovirus-mediated ectopic overexpression of RIPK3 but not RIPK1. Besides, PTS inhibited ethanol-induced hepatocyte steatosis via restricting lipogenesis and enhancing lipolysis, decreased oxidative stress via rescuing mitochondrial membrane potential, reducing oxidative system, and enhancing antioxidant system, and relieved inflammation evidenced by decreased expression of proinflammatory factors. Notably, RIPK3 overexpression diminished these protective effects of PTS. Subsequent work indicated that PTS suppressed the expression and nuclear translocation of nuclear factor of activated T-cells 4 (NFATc4), an acetylated protein, in ethanol-exposed hepatocytes, while NFATc4 overexpression impaired the negative regulation of PTS on RIPK3 and DAMPs release. Further, PTS rescued sirtuin 2 (SIRT2) expression, and SIRT2 knockdown abrogated the inhibitory effects of PTS on nuclear translocation and acetylation status of NFATc4 in ethanol-incubated hepatocytes. In conclusion, PTS attenuated RIPK3-dependent hepatocyte necroptosis after ethanol exposure via SIRT2-mediated NFATc4 deacetylation.

Bioprotective and Functional Effect of Carnosine on Sepsis Induced Renal Damage in Male Albino Rat Model through Targeting IL-1β and TNF-α Production

Acute kidney injury (AKI), one of the frequently diagnosed and serious sepsis induced complication has high morbidity and mortality. The present study investigated the bioprotective and functional effect of carnosine on AKI induced pathological damage in Male Albino rat model in vivo. AKI in Albino rats was induced by cecal ligation and puncture surgery where as TNF-α and IL-1β levels were detected using ELISA assay. Protein expression was examined by western blotting and pathological damage using hematoxylin and eosin (H&E). Treatment with carnosine suppressed AKI induced urea nitrogen and creatinine in Male Albino rat serum in dose-dependent manner. Development of sepsis mediated renal injury in Albino rats was also effectively prevented on treatment with carnosine. Secretion of AKI-induced IL-1β, IL-18, and TNF-α in renal tissues was alleviated significantly in Albino rats by carnosine treatment. Additionally, in carnosine-treated Albino rats renal tissues AKI induced Bax expression was alleviated while as Bcl-2 was promoted compared to AKI Albino rats. Carnosine treatment improved the survival rate of the Albino rats with AKI. Carnosine inhibits renal tissue damage and increases survival rate in AKI Albino rat model. The mechanism involves alleviation of inflammatory cytokine secretion and promotion of Bcl-2 expression. Thus, carnosine may be used as a therapeutic agent for treatment of AKI.

Protective effects of Nrf2 against sepsis-induced hepatic injury

AIM

This study was designed to investigate the changes of liver injury and Nrf2 signaling pathway in the process of sepsis. We also aimed to examine the role of Nrf2 in resisting oxidative stress and relieving inflammation in sepsis-induced hepatic injury.

MAIN METHODS

By operating cecal ligation and puncture (CLP) on Nrf2^-/- mice and wild type mice, a sepsis-induced hepatic injury model was established. We compared and contrasted the wild type mice with the Nrf2^-/- mice during sepsis-induced hepatic injury, and evaluated the liver damage by biochemical analyses and staining hematoxylin-eosin (HE). Western blot or real-time PCR was performed to detect Nrf2 and its regulated genes NQO-1, GCLM and HO-1. Additionally, we detected the expressions and secretion of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), IL-1β and anti-inflammatory cytokines IL-10. We assessed the oxidative stress through the levels of MDA and NO.

KEY FINDINGS

The results showed that Nrf2 expressions at mRNA and protein levels were increased 1 day after CLP, namely the early stage of sepsis. Compared with wild type mice after CLP, Nrf2^-/- mice showed more severe liver injury, accompanied by higher expression of inflammatory cytokines and oxidative stress. Notably, Nrf2-regulated genes GCLM and NQO-1, were strongly downregulated in Nrf2^-/- mice.

SIGNIFICANCE

Nrf2 was probably implicated in decreasing inflammatory cytokine levels and counteracting oxidative stress to alleviate sepsis-induced hepatic injury, mainly through regulating GCLM and NQO-1 in the early stage after CLP.

Hepatoprotective effect of anemoside B4 against sepsis-induced acute liver injury through modulating the mTOR/p70S6K-mediated autophagy

Sepsis triggers liver dysfunction with high morbidity and mortality. Here, we elucidated the effect of anemoside B4 on sepsis in cecal ligation and puncture (CLP)-induced mouse model and LPS-induced primary hepatocytes. Following CLP surgery, septic mice were intraperitoneally injected with anemoside B4 (50 or 100 mg/kg). Anemoside B4 improved septic mouse survival rate, decreased serum AST and ALT levels and attenuated liver histopathologic damages. Western blot analysis showed that anemoside B4 elevated the expression of Beclin-1, LC3II/LC3I, Atg3, Atg5, and Atg7, and reduced p62, suggesting the restoration of autophagy flux in liver. More autophagic vesicles were observed in liver after anemoside B4 treatment using transmission electron microscopy. Using ELISA and commercial enzyme kits, we found that anemoside B4 decreased serum TNF-α, IL-6, and IL-1β levels and increased CAT, SOD and GSH activities. TUNEL staining and western blot revealed that anemoside B4 suppressed cell apoptosis, along with decreased Bax, leaved caspase-3, cleaved PARP, but increased Bcl-2. Consistent with in vivo findings, anemoside B4 inhibited apoptosis, inflammatory response, and oxidative stress and enhanced autophagy in LPS-induced primary hepatocytes. Importantly, these cellular processes were possibly mediated by mTOR/p70S6K signaling, as reflected by the offset of 3-MA in the immunosuppression of anemoside B4.

Protective effects of pterostilbene against hepatic damage, redox imbalance, mitochondrial dysfunction, and endoplasmic reticulum stress in weanling piglets

This investigation evaluated the potential of natural antioxidants, pterostilbene (PT) and its parent compound resveratrol (RSV), to alleviate hepatic damage, redox imbalance, mitochondrial dysfunction, and endoplasmic reticulum (ER) stress in early-weaned piglets. A total of 144 suckling piglets were randomly assigned to four treatments (six replicates per group, n = 6): 1) sow reared, 2) early weaned and fed a basal diet, 3) early weaned and fed the basal diet supplemented with 300 mg/kg PT, or with 4) 300 mg/kg RSV. Early weaning increased plasma alanine aminotransferase (P = 0.004) and aspartate aminotransferase (P = 0.009) activities and hepatic apoptotic rate (P = 0.001) in piglets compared with the sow-reared piglets. Early weaning decreased hepatic adenosine triphosphate (ATP; P = 0.006) content and mitochondrial complexes III (P = 0.019) and IV activities (P = 0.038), but it increased superoxide anion accumulation (P = 0.026) and the expression levels of ER stress markers, such as glucose-regulated protein 78 (P < 0.001), CCAAT/enhancer-binding protein-homologous protein (P = 0.001), and activating transcription factor (ATF) 4 (P = 0.006). PT was superior to RSV at mitigating liver injury and oxidative stress after early weaning, as indicated by decreases in the number of apoptotic cells (P = 0.036) and the levels of superoxide anion (P = 0.002) and 8-hydroxy-2 deoxyguanosine (P < 0.001). PT increased mitochondrial deoxyribonucleic acid content (P = 0.031) and the activities of citrate synthase (P = 0.005), complexes I (P = 0.004) and III (P = 0.011), and ATP synthase (P = 0.041), which may contribute to the mitigation of hepatic ATP deficit (P = 0.017) in the PT-treated weaned piglets. PT also prevented increases in the ER stress marker and ATF 6 expression levels and in the phosphorylation of inositol-requiring enzyme 1 alpha caused by early weaning (P < 0.05). PT increased sirtuin 1 activity (P = 0.031) in the liver of early-weaned piglets than those in the early-weaned piglets fed a basal diet. In conclusion, PT supplementation alleviates liver injury in weanling piglets probably by inhibiting mitochondrial dysfunction and ER stress.

Co-encapsulation of HNF4α overexpressing UMSCs and human primary hepatocytes ameliorates mouse acute liver failure

BACKGROUND

Acute liver failure (ALF) is a complicated condition that is characterized by global hepatocyte death and often requires immediate liver transplantation. However, this therapy is limited by shortage of donor organs. Mesenchymal stem cells (MSCs) and hepatocytes are two attractive sources of cell-based therapies to treat ALF. The combined transplantation of hepatocytes and MSCs is considered to be more effective for the treatment of ALF than single-cell transplantation. We have previously demonstrated that HNF4α-overexpressing human umbilical cord MSCs (HNF4α-UMSCs) promoted the expression of hepatic-specific genes. In addition, microencapsulation allows exchange of nutrients, forming a protective barrier to the transplanted cells. Moreover, encapsulation of hepatocytes improves the viability and synthetic ability of hepatocytes and circumvents immune rejection. This study aimed to investigate the therapeutic effect of microencapsulation of hepatocytes and HNF4α-UMSCs in ALF mice.

METHODS

Human hepatocytes and UMSCs were obtained separately from liver and umbilical cord, followed by co-encapsulation and transplantation into mice by intraperitoneal injection. LPS/D-gal was used to induce ALF by intraperitoneal injection 24 h after transplantation. In addition, Raw 264.7 cells (a macrophage cell line) were used to elucidate the effect of HNF4α-UMSCs-hepatocyte microcapsules on polarization of macrophages. The protein chip was used to define the important paracrine factors in the conditioned mediums (CMs) of UMSCs and HNF4α-UMSCs and investigate the possible mechanism of HNF4α-UMSCs for the treatment of ALF in mice.

RESULTS

HNF4α-UMSCs can enhance the function of primary hepatocytes in alginate-poly-L-lysine-alginate (APA) microcapsules. The co-encapsulation of both HNF4α-UMSCs and hepatocytes achieved better therapeutic effects in ALF mice by promoting M2 macrophage polarization and reducing inflammatory response mainly mediated by the paracrine factor HB-EGF secreted by HNF4α-UMSCs.

CONCLUSIONS

The present study confirms that the co-encapsulation of HNF4α-UMSC and hepatocytes could exert therapeutic effect on ALF mainly by HB-EGF secreted by HNF4α-UMSCs and provides a novel strategy for the treatment of ALF.

Role of resveratrol in protecting vasodilatation function in septic shock rats and its mechanism

BACKGROUND

Vascular dysfunction is a major cause of sepsis-induced multiple-organ dysfunction. Resveratrol is a polyphenol compound with extensive pharmacological effects including anti-inflammation. The aim of this study was to determine the role and mechanism of resveratrol in protecting vascular function following sepsis.

METHODS

The cecal ligation and puncture method was used to establish a septic shock rat model. Resveratrol (5 mg/kg and 10 mg/kg) was administered intravenously immediately and at 12 hours after cecal ligation and puncture, respectively. The effects of resveratrol on vasodilatation function, blood flow velocity, hemodynamics, and vital organ function and its relationship to Rac-1 and HIF-1α were observed.

RESULTS

Vascular relaxation reactivity and blood flow velocity were significantly decreased after septic shock, both were significantly improved by resveratrol 5 mg/kg and 10 mg/kg, and the effect of 10 mg/kg was greater. The relaxation reactivity of the superior mesenteric artery to acetylcholine (Ach) was increased by 43.2%. The blood flow velocity of mesenteric arterioles and venules was increased by 47.1% and 51%, respectively, after resveratrol (10 mg/kg) administration compared with the septic shock group. The hemodynamics and both liver and kidney blood flow were significantly decreased after septic shock, which were significantly improved them by resveratrol, which enhanced the vascular relaxation reactivity in septic shock rats. The 72-hour survival rate of septic shock rats in the resveratrol group (62.5%) was significantly higher than that in the septic shock group (6.3%). Resveratrol significantly upregulated the expression of endothelial nitric oxide synthase (eNOS) and downregulated the expression of inducible NOS, Rac-1, and HIF-1α. Inhibitors of Rac-1 and HIF-1α significantly improved the expression of eNOS, and inhibition of eNOS (L-NAME, 5 mg/kg) antagonized the resveratrol-induced improvement in vascular relaxation reactivity and survival.

CONCLUSION

Resveratrol was beneficial for vasodilatation function in rats with septic shock, which is the major contribution to resveratrol improving hemodynamics and organ perfusion. The mechanism involved resveratrol upregulating the expression of eNOS by inhibiting Rac-1 and HIF-1α.

l-theanine alleviates liver and kidney dysfunction in septic rats induced by cecal ligation and puncture

AIMS

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response against infection that triggers systemic inflammatory response syndrome. l-theanine (LT), a glutamate derivative, is a non-protein amino acid derived from tea (Camellia sinensis), and a valuable nutraceutical product used as an additive in the food industry. This study we aimed to investigate whether LT would exert any therapeutic effect on liver and kidney tissues in Sprague Dawley rats with sepsis induced with cecal ligation and puncture (CLP).

MAIN METHODS

Rats were divided into four groups; sham, CLP, CLP+LT1 (2x250 mg/kg) and CLP+LT2 (2 × 750 mg/kg). Liver and kidney tissues were subjected to histopathological examination. Apoptotic index percentages (AI%) were examined using the TUNEL method. The oxidized glutathione to total glutathione (GSSG/TGSH) ratio (as a marker of oxidative stress, levels of caspase-3 (a marker of apoptosis), glutathione peroxidase (GPx) and glutathione S-transferase (GST) (as antioxidant enzymes), inducible nitric oxide synthase (iNOS) and the tumor necrosis factor-α to Interleukin-10 ratio (TNF-α/IL-10) (as markers of inflammation) were investigated using commercial kits. Levels of malondialdehyde (MDA) (a marker of oxidative stress) were determined spectrophotometrically.

KEY FINDINGS

A high dose of LT exhibited more significant effects in reducing oxidative stress, inflammation and apoptosis than a low dose of LT in liver and kidney tissues with CLP-induced sepsis (p < 0.05).

SIGNIFICANCE

Our results indicated that LT significantly and dose-dependently inhibited sepsis induced liver and kidney injury. This effect may be attributed to the antioxidant, anti-inflammatory, and anti-apoptotic activities of LT.

Antioxidant Alternatives in the Treatment of Amyotrophic Lateral Sclerosis: A Comprehensive Review

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that produces a selective loss of the motor neurons of the spinal cord, brain stem and motor cortex. Oxidative stress (OS) associated with mitochondrial dysfunction and the deterioration of the electron transport chain has been shown to be a factor that contributes to neurodegeneration and plays a potential role in the pathogenesis of ALS. The regions of the central nervous system affected have high levels of reactive oxygen species (ROS) and reduced antioxidant defenses. Scientific studies propose treatment with antioxidants to combat the characteristic OS and the regeneration of nicotinamide adenine dinucleotide (NAD+) levels by the use of precursors. This review examines the possible roles of nicotinamide riboside and pterostilbene as therapeutic strategies in ALS.

Pterostilbene Improves Hepatic Lipid Accumulation via the MiR-34a/Sirt1/SREBP-1 Pathway in Fructose-Fed Rats

High fructose intake promotes hepatic lipid accumulation. Pterostilbene, a natural analogue of resveratrol found in diet berries, exhibits a hepatoprotective property. Here, we studied the protection by pterostilbene against fructose-induced hepatic lipid accumulation and explored its possible mechanism. We observed a high expression of microRNA-34a (miR-34a, P < 0.05) and a low expression of its target, sirtuin1 (Sirt1, mRNA: P < 0.01; protein: P < 0.001), with the overactivation of downstream sterol regulatory element-binding protein-1 (SREBP-1) lipogenic pathway (nuclear SREBP-1 protein: P < 0.05; FAS and SCD1 mRNA: P < 0.01), in rat livers, as well as BRL-3A and HepG2 cells, stimulated by fructose. More interestingly, pterostilbene recovered the fructose-disturbed miR-34a expression (0.3-0.5-fold vs fructose control, P < 0.05), Sirt1 protein level (1.2- to 1.5-fold vs fructose control, P < 0.05), and SREBP-1 lipogenic pathway, resulting in significant amelioration of hepatocyte lipid accumulation in animal [hepatic triglyceride and total cholesterol (TG&TC) mg/g·wet tissue: 4.90 ± 0.19, 5.23 ± 0.16, 5.20 ± 0.29 vs fructose control 9.73 ± 1.06, P < 0.001; 3.18 ± 0.30, 3.31 ± 0.39, 3.37 ± 0.47 vs 5.67 ± 0.28, P < 0.001] and cell models (BRL-3A TG&TC mmol/g·protein: 0.123 ± 0.011 vs 0.177 ± 0.004, P < 0.001; 0.169 ± 0.011 vs 0.202 ± 0.008, P < 0.05; HepG2: 0.257 ± 0.005 vs 0.303 ± 0.016, P < 0.05; 0.143 ± 0.004 vs 0.201 ± 0.008, P < 0.001). These results provide the experimental evidence supporting the anti-lipogenic effect of pterostilbene against fructose-induced hepatic lipid accumulation via modulating the miR-34a/Sirt1/SREBP-1 pathway.

PGC1α activation by pterostilbene ameliorates acute doxorubicin cardiotoxicity by reducing oxidative stress via enhancing AMPK and SIRT1 cascades

Doxorubicin (DOX) is a widely used and potent anticancer agent, but DOX dose-dependently induced cardiotoxicity greatly limits its use in clinic. Pterostilbene, a natural analog of resveratrol, is a known antioxidant and exerts myocardial protection. The present study explored the action and detailed mechanism of pterostilbene on DOX-treated cardiomyocytes. We investigated the effects of pterostilbene on established acute DOX-induced cardiotoxicity models in both H9c2 cells treated with 1 μM DOX and C57BL/6 mice with DOX (20 mg/kg cumulative dose) exposure. Pterostilbene markedly alleviated the DOX exposure-induced acute myocardial injury. Both in vitro and in vivo studies revealed that pterostilbene inhibited the acute DOX exposure-caused oxidative stress and mitochondrial morphological disorder via the PGC1α upregulation through activating AMPK and via PGC1α deacetylation through enhancing SIRT1. However, these effects were partially reversed by knockdown of AMPK or SIRT1 in vitro and treatment of Compound C (AMPK inhibitor) or EX527 (SIRT1 inhibitor) in vivo. Our results indicate that pterostilbene protects cardiomyocytes from acute DOX exposure-induced oxidative stress and mitochondrial damage via PGC1α upregulation and deacetylation through activating AMPK and SIRT1 cascades.

Inhibition of eIF2α dephosphorylation accelerates pterostilbene-induced cell death in human hepatocellular carcinoma cells in an ER stress and autophagy-dependent manner

Hepatocellular carcinoma (HCC) is the one of the most common cancers worldwide. Because the side effects of current treatments are severe, new effective therapeutic strategies are urgently required. Pterostilbene (PT), a natural analogue of resveratrol, has diverse pharmacologic activities, including antioxidative, anti-inflammatory and antiproliferative activities. Here we demonstrated that PT inhibits HCC cell growth without the induction of apoptosis in an endoplasmic reticulum (ER) stress- and autophagy-dependent manner. Mechanistic studies indicated that the combination of salubrinal and PT modulates ER stress-related autophagy through the phospho-eukaryotic initiation factor 2α/activating transcription factor-4/LC3 pathway, leading to a further inhibition of eIF2α dephosphorylation and the potentiation of cell death. An in vivo xenograft analysis revealed that PT significantly reduced tumour growth in mice with a SK-Hep-1 tumour xenograft. Taken together, our results yield novel insights into the pivotal roles of PT in ER stress- and autophagy-dependent cell death in HCC cells.

Molecular docking analysis of imine stilbene analogs and evaluation of their anti-aging activity using yeast and mammalian cell models

The NAD⁺-dependent histone deacetylase SIRT1 was shown to be associated with aging and longevity. A stilbene, resveratrol (RV) was shown to exert anti-aging activity by stimulating the SIRT1 activity. However, the utility of RV is limited by its low bioavailability and structural instability. It is thus envisaged to test imine stilbene (IMS) analogs of RV for their potential anti-aging activity. In the present study, molecular docking analysis of five IMS analogs (3a, 3b, 3c, 3d and 3e) against the SIRT1 protein has been carried out. All the five IMS analogs displayed enhanced binding affinity towards SIRT1; three out of five IMS analogs (3a, 3 b, 3e) showed significantly higher affinity with lower binding energies (-9.58, -9.54, and -9.82 kcal mol^-1) than RV (-8.11 kcal mol^-1). Further, experimental validation of anti-aging activity was performed by measuring the chronological life span in vitro using yeast and cellular replicative senescence (CRS) in mammalian cell line models. All IMS analogs extended the chronological life span in yeast as compared to untreated cells as well as RV treated cells. Enhanced anti-aging activity was also observed in an analogous mammalian cell line model upon treatment with either RV or IMS analogs. The results thus suggest that most of the IMS analogs tested may serve as potent drug lead molecules with anti-aging activity.

Pterostilbene prevents hepatocyte epithelial-mesenchymal transition in fructose-induced liver fibrosis through suppressing miR-34a/Sirt1/p53 and TGF-β1/Smads signalling

BACKGROUND AND PURPOSE

Excessive fructose consumption is a risk factor for liver fibrosis. Pterostilbene protects against liver fibrosis. Here, we investigated the potential role and the mechanisms underlying the hepatocyte epithelial-mesenchymal transition (EMT) in fructose-induced liver fibrosis and protection by pterostilbene.

EXPERIMENTAL APPROACH

Characteristic features of liver fibrosis in 10% fructose-fed rats and EMT in 5 mM fructose-exposed BRL-3A cells with or without pterostilbene and the change of miR-34a/Sirt1/p53 and transforming growth factor-β1 (TGF-β1)/Smads signalling were examined. MiR-34a inhibitor, miR-34a minic, or p53 siRNA were used to explore the role of miR-34a/Sirt1/p53 signalling in fructose-induced EMT and the action of pterostilbene.

KEY RESULTS

Pterostilbene prevented fructose-induced liver injury with fibrosis in rats. Fructose caused hepatocyte undergoing EMT, gaining fibroblast-specific protein 1 and vimentin, and losing E-cadherin, effects attenuated by pterostilbene. Moreover, fructose induced miR-34a overexpression in hepatocytes with down-regulated Sirt1, increased p53 and ac-p53, and activated TGF-β1/Smads signalling, whereas these disturbances were suppressed by miR-34a inhibitor. Additionally, miR-34a inhibitor and p53 siRNA prevented TGF-β1-driven hepatocyte EMT under fructose exposure. Pterostilbene down-regulated miR-34a, up-regulated Sirt1, and suppressed p53 activation and TGF-β1/Smads signalling in fructose-stimulated animals and cells but showed no additional effects with miR-34a inhibitor on miR-34a/Sirt1/p53 signalling in fructose-exposed hepatocytes.

CONCLUSIONS AND IMPLICATIONS

These results strongly suggest that activation of miR-34a/Sirt1/p53 signalling is required for fructose-induced hepatocyte EMT mediated by TGF-β1/Smads signalling, contributing to liver fibrosis in rats. Pterostilbene exhibits a protective effect against liver fibrosis at least partly through inhibiting miR-34a/Sirt1/p53 signalling activation.

Acetaminophen Responsive miR-19b Modulates SIRT1/Nrf2 Signaling Pathway in Drug-Induced Hepatotoxicity

Previous studies suggest that activation of SIRT1 protects liver from acetaminophen (APAP)-induced injury; however, the detailed mechanism of SIRT1 modulation in this process is still incomplete. Therefore, this study was to investigate the pathophysiological role of SIRT1 in APAP-mediated hepatotoxicity. We found that SIRT1 mRNA and protein were markedly upregulated in human LO2 cells and mouse liver upon APAP exposure. In vitro, the specific knockdown of SIRT1 expression ultimately aggravated APAP-evoked cellular antioxidant defense in LO2 cells. Moreover, lentivirus-mediated knockdown of hepatic SIRT1 expression exacerbated APAP-induced oxidative stress and liver injury, especially reduction of Nrf2 and subsequent downregulation of several antioxidant genes. Intriguingly, 30 mg/kg SRT1720, the specific SIRT1 activator, which greatly enhanced Nrf2 expression and antioxidant defense, and then eventually reversed APAP-induced hepatic liver injury in mice. Furthermore, APAP responsive miR-19b played an important role in regulating SIRT1 expression, whereas overexpression miR-19b largely abolished the induction of SIRT1 by APAP in vitro and in vivo. Specific SIRT1 3′-UTR mutation, which disrupted the interaction of miRNA-3′UTR, and successfully abrogated the modulation by miR-19b. Notably, hepatic miR-19b overexpression worsened the APAP-induced hepatotoxicity. In general, our results support the notion that the strong elevation of SIRT1 by APAP responsive miR-19b may represent a compensatory mechanism to protect liver against the drug-induced damage, at least in part by enhancing Nrf2-mediated antioxidant capacity in the liver.

The Beneficial Roles of SIRT1 in Drug-Induced Liver Injury

Drug-induced liver injury (DILI) is a major cause of acute liver failure (ALF) as a result of accumulated drugs in the human body metabolized into toxic agents and helps generate heavy oxidative stress, inflammation, and apoptosis, which induces necrosis in hepatocytes and ultimately damages the liver. Sirtuin 1 (SIRT1) is said to have multiple vital roles in cell proliferation, aging, and antistress systems of the human body. The levels of SIRT1 and its activation precisely modulate its critical role in the interaction between multiple step procedures of DILI. The nuclear factor kappa-light-chain-enhancer of activated B cell- (NF-κB-) mediated inflammation signaling pathway, reactive oxygen species (ROS), DNA damage, mitochondrial membrane potential collapse, and endoplasmic reticulum (ER) stress also contribute to aggravate DILI. Apoptosis is regarded as the terminal reaction followed by multiple signaling cascades including caspases, p53, and mitochondrial dysfunction which have been said to contribute in DILI. The SIRT1 activator is regarded as a potential candidate for DILI, because the former could inhibit signaling of p53, NF-κB, and ER stress. On the other hand, overexpression of SIRT1 also enhances the activation of antioxidant responses via Kelch-like ECH-associated protein 1- (Keap1-) nuclear factor- (erythroid-derived 2-) like 2 (Nrf2) signaling. The current manuscript will highlight the mechanism of DILI and the interaction of SIRT1 with various cytoplasmic factors leading to DILI along with the summary of potent SIRT1 agonists.

SIRT1 activation by butein attenuates sepsis-induced brain injury in mice subjected to cecal ligation and puncture via alleviating inflammatory and oxidative stress

Sepsis-induced brain injury is frequently encountered in critically ill patients with severe systemic infection. Butein (3,4,2',4'-tetrahydroxychalcone) has been demonstrated as the neuro-protective agent via reducing inflammation and oxidative stress on neurons. Moreover, activation of silent information regulator 1 (SIRT1) inhibits apoptosis, oxidation and inflammation thus alleviating sepsis-induced multiorgan injuries. In present study, we show that butein administrated intraperitoneally (10 mg/kg) saved mice from sepsis-induced lethality by increasing 7-day survival rate after cecal ligation and puncture (CLP) surgery. Additionally, butein treatment enhanced SIRT1 signaling thus decreasing the Ac-NF-κB, Ac-FOXO1 and Ac-p53 levels, thus attenuating the brain injury of mice after CLP surgery by decreasing cerebral edema, maintaining the blood-brain barrier integrity, inhibiting neuronal apoptosis, and decreasing pro-inflammatory cytokines production (IL-6, TNF-α and IL-1β) and oxidative stress (downregulation of MDA, and upregulation of SOD and CAT) in both serum and cerebral cortex tissues. Moreover, butein treatment attenuated LPS induced neurological function loss. However, all above mentioned neuro-protective actions of butein were partially inhibited by EX527 co-treatment, one standard SIRT1 inhibitor. Collectively, butein attenuates sepsis-induced brain injury through alleviation of cerebral inflammation, oxidative stress and apoptosis by SIRT1 signaling activation.