Effects of S-allyl cysteine on lung and liver tissue in a rat model of lipopolysaccharide-induced sepsis

Thiosulfinate-Enriched Allium sativum Extract Exhibits Differential Effects between Healthy and Sepsis Patients: The Implication of HIF-1α

Garlic (Allium sativum) has historically been associated with antioxidant, immunomodulatory, and microbiocidal properties, mainly due to its richness in thiosulfates and sulfur-containing phytoconstituents. Sepsis patients could benefit from these properties because it involves both inflammatory and refractory processes. We evaluated the effects of thiosulfinate-enriched Allium sativum extract (TASE) on the immune response to bacterial lipopolysaccharide (LPS) by monocytes from healthy volunteers (HVs) and patients with sepsis. We also explored the TASE effects in HIF-1α, described as the key transcription factor leading to endotoxin tolerance in sepsis monocytes through IRAK-M expression. Our results showed TASE reduced the LPS-triggered reactive oxygen species (ROS) production in monocytes from both patients with sepsis and HVs. Moreover, this extract significantly reduced tumor necrosis factor (TNF)-α, interleukin-1β, and interleukin-6 production in LPS-stimulated monocytes from HVs. However, TASE enhanced the inflammatory response in monocytes from patients with sepsis along with increased expression of human leukocyte antigen-DR. Curiously, these dual effects of TASE on immune response were also found when the HV cohort was divided into low- and high-LPS responders. Although TASE enhanced TNFα production in the LPS-low responders, it decreased the inflammatory response in the LPS-high responders. Furthermore, TASE decreased the HIF-1α pathway-associated genes IRAK-M, VEGFA and PD-L1 in sepsis cells, suggesting HIF-1α inhibition by TASE leads to higher cytokine production in these cells as a consequence of IRAK-M downregulation. The suppression of this pathway by TASE was confirmed in vitro with the prolyl hydroxylase inhibitor dimethyloxalylglycine. Our data revealed TASE’s dual effect on monocyte response according to status/phenotype and suggested the HIF-1α suppression as the possible underlying mechanism.

Black Garlic and Thiosulfinate-Enriched Extracts as Adjuvants to Ceftriaxone Treatment in a Rat Peritonitis Model of Sepsis

To date, there have been no new drugs or adjuvants able to decrease both morbidity and mortality in the context of sepsis and septic shock. Our objective was to evaluate the use of thiosulfinate-enriched Allium sativum and black garlic extracts as adjuvants in the management of sepsis. An experimental in vivo study was carried out with male Sprague-Dawley^® rats. Animals were randomized in four treatment groups: antibiotic (ceftriaxone) treatment (group I), ceftriaxone plus thiosulfinate-enriched extract (TASE, group II), ceftriaxone plus thiosulfinate-enriched extract and black garlic extracts (TASE + BGE, group III), and ceftriaxone plus black garlic extract (BGE, group IV). All animals were housed and inoculated with 1 × 10¹⁰ CFU/15 mL of intraperitoneal Escherichia coli ATCC 25922. Subsequently, they received a daily treatment according to each group for 7 days. Clinical, analytical, microbiological, and histopathological parameters were evaluated. Statistically significant clinical improvement was observed in rats receiving garlic extracts in weight (groups II and III), ocular secretions, and piloerection (group IV). Moreover, less liver edema, vacuolization, and inflammation were observed in groups receiving adjuvant support (groups II, III, and IV). When comparing interleukins 24 h after bacteria inoculum, we found statistically significant differences in TNF-alpha levels in groups receiving BGE (groups III and IV, p ≤ 0.05). Blood and peritoneal liquid cultures were also analyzed, and we detected a certain level of Enterococcus faecalis in peritoneal cultures from all treatment groups and less bacteria presence in blood cultures in rats receiving garlic extracts (groups II, III, and IV). In conclusion, TASE and BGE could be promising nutraceutical or medicinal agents as coadjuvants in the treatment of sepsis because of its effects in modulating the inflammatory response.

Ginger and 6-gingerol prevent lipopolysaccharide-induced intestinal barrier damage and liver injury in mice

BACKGROUND

Inflammation-related diseases present a significant public health problem. Ginger is a flavoring spice and medicinal herb with anti-inflammatory activity. This study investigated the preventive effects of ginger extract (GE) and its main bioactive component, 6-gingerol (6G), on lipopolysaccharide (LPS)-induced intestinal barrier dysfunction and liver injury in mice.

RESULTS

GE and 6G were orally administered to mice for seven consecutive days before LPS administration. After 24 h, the mice were sacrificed. GE and 6G were found to significantly reverse LPS-induced inflammation in the mouse ileum by modifying the NF-κB pathway. They also alleviated apoptosis in the ileum by downregulating Bax and cytochrome c gene expression and by inhibiting the caspase-3 pathway. Through the aforementioned mechanisms, GE and 6G restored the intestinal barrier by increasing ZO-1 and claudin-1 protein expressions. Gut-derived LPS induced inflammation and apoptosis in the liver; these effects were markedly reversed through GE and 6G treatment. 6G was the most abundant component in GE, as evidenced through liquid chromatography-mass spectrometry, and accounted for >50% of total gingerols and shogaols in GE.

CONCLUSION

The current results support the use of GE and 6G as dietary supplements to protect against gut-derived endotoxemia-associated inflammatory response and disorders. © 2021 Society of Chemical Industry.

Potassium Dichromate-Induced Hepato- and Hematotoxicity in Rats: Nutritive Composition and Ameliorative Role of Acacia nilotica L. Leaf

Background: Chromium and its salts, as well as chromium-containing compounds, play a major role in numerous manufacturing processes and have been contraindicated in carcinogenic, toxic, and mutagenic conditions in people involved in these processes. Objectives: This study investigated the ameliorative role of Acacia nilotica aqueous leave extract (ANLA) on potassium dichromate-induced liver and blood toxicity in male and female rats. Phytochemical screening and nutrient composition of ANLA were also evaluated. Methods: Phytochemical and proximate analysis of ANLA were carried out. Twenty adult male and female rats each were divided into four groups (n = 10): (1) control; (2) potassium dichromate (PDC; 0.625 mg/kg body weight); (3) PDC co-treated with ANLA after seven days (650 mg/kg bwt); and (4) PDC co-treated with ANLA (650 mg/kg bwt) simultaneously for 21 days. Biomarkers of liver injury, lipid, and hematological imbalance were assessed. Tissue histology and toxicant retention were done. Results: Various plant secondary metabolites (flavonoids, terpenoids, tannins, phenols, saponins, cardiac glycosides, alkaloids, and anthraquinones) and nutrients (protein = 67.41 ± 2.44%; carbohydrate = 9.87 ± 1.87%; fiber = 10.01 ± 1.21%; mineral = 6.41 ± 1.08%; fat and oil = 6.63 ± 0.93%) were identified in the leave. Exposure to chromium significantly (P < 0.05) increased plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) with a concomitant decrease in the activity of these enzymes in the liver of both male and female rats. The exposure also altered protein, triglyceride, and cholesterol levels in the plasma and liver as well as hematological indices. Organ chromium retention and pathological changes were also observed. ANLA modulated these chromium-induced alterations in the rats. Conclusions: Based on the results, ANLA possesses ameliorative property against PDC-induced toxicity in rats. Thus it may be used to combat chromium poisoning. The nutritive potential of A. nilotica leaves may also be maximized.

Elucidation of S-Allylcysteine Role in Inducing Apoptosis by Inhibiting PD-L1 Expression in Human Lung Cancer Cells

AIM

The aim of this study is to explore the therapeutic potential of S-allylcysteine (SAC) organosulphur compound as a potent immune checkpoint inhibitor PD-L1.

BACKGROUND

Natural compounds have been showing tremendous anticancerous potential via suppressing the expression of genes involved in the development and progression of several carcinomas. This has further motivated us to explore the therapeutic potential of organosulphur compounds as potent immune checkpoint inhibitors.

OBJECTIVE

Our study was designed to elucidate the potential of S-allylcysteine (SAC) as significant PD-L1 (immune checkpoint) inhibitor in human lung cancer A549 cancer cell line by using both the in vitro and in silico approaches.

METHODS

Anticancerous effect of the SAC on lung cancer cells was determined by using the MTT cell viability. Apoptotic induction was confirmed by Hoechst staining, percent caspase-3 activity as well as gene expression analysis by real time PCR. Reactive Oxygen Species (ROS) was estimated by DCFDA method. Additionally, ligand-target protein interaction was analysed by molecular docking.

RESULT

Cell growth and proliferation was significantly reduced in SAC treated A549 cells in a concentration and time.dependent manner. The effect of SAC on apoptotic induction was analyzed by enhanced nuclear condensation, increased percent caspase-3 activity as well as modulation of apoptotic genes. Furthermore, SAC treatment also resulted in reduced expression of PD-L1 and HIF-1α. Additionally, in silico analysis also supported the in vitro findings by showing efficient docking with PD-L1 immune checkpoint target.

CONCLUSION

Therefore, our results clearly suggested that SAC could serve as a novel chemotherapeutic candidate for the treatment of lung cancer by inhibiting immune checkpoint target PD-L1 in human lung cancer cells. Additionally, our study also explained a novel molecular mechanism of its antitumor activity.

C-Terminal Amination of a Cationic Anti-Inflammatory Peptide Improves Bioavailability and Inhibitory Activity Against LPS-Induced Inflammation

Lipopolysaccharide (LPS) has been implicated as a major cause of inflammation and an uncontrolled LPS response increases the risk of localized inflammation and sepsis. While some native peptides are helpful in the treatment of LPS-induced inflammation, the use of these peptides is limited due to their potential cytotoxicity and poor anti-inflammatory activity. Hybridization is an effective approach for overcoming this problem. In this study, a novel hybrid anti-inflammatory peptide that combines the active center of Cathelicidin 2 (CATH2) with thymopentin (TP5) was designed [CTP, CATH2 (1–13)-TP5]. CTP was found to have higher anti-inflammatory effects than its parental peptides through directly LPS neutralization. However, CTP scarcely inhibited the attachment of LPS to cell membranes or suppressed an established LPS-induced inflammation due to poor cellular uptake. The C-terminal amine modification of CTP (CTP-NH₂) was then designed based on the hypothesis that C-terminal amidation can enhance the cell uptake by increasing the hydrophobicity of the peptide. Compared with CTP, CTP-NH₂ showed enhanced anti-inflammatory activity and lower cytotoxicity. CTP-NH₂ not only has strong LPS neutralizing activity, but also can significantly inhibit the LPS attachment and the intracellular inflammatory response. The intracellular anti-inflammatory effect of CTP-NH₂ was associated with blocking of LPS binding to the Toll-like receptor 4-myeloid differentiation factor 2 complex and inhibiting the nuclear factor-kappa B pathway. In addition, the anti-inflammatory effect of CTP-NH₂ was confirmed using a murine LPS-induced sepsis model. Collectively, these findings suggest that CTP-NH₂ could be developed into a novel anti-inflammatory drug. This successful modification provides a design strategy to improve the cellular uptake and anti-inflammatory activity of peptide agents.

The role of phytochemicals in sepsis: A mechanistic and therapeutic perspective

Sepsis and septic shock are still a leading cause of mortality and morbidity in intensive care units worldwide. Sepsis is an uncontrolled and excessive response of the innate immune system toward the invading infectious microbes, characterized by the hyper-production of pro-inflammatory mediators such as interleukin (IL)-1β, IL-6, tumor-necrosis factor (TNF)-α, and high-mobility group box 1 (HMGB1). In severe sepsis, the overwhelming production of pro-inflammatory cytokines and reactive oxygen species may compromise organ function and lead to the induction of abnormal apoptosis in different organs, resulting in multiple organ dysfunction syndrome and death. Hence, compounds that are able to attenuate inflammatory responses may have therapeutic potential for sepsis treatment. Understanding the pathophysiology and underlying molecular mechanisms of sepsis may provide useful insights in the discovery and development of new effective therapeutics. Therefore, numerous studies have invested much effort into elucidating the mechanisms involved with the onset and development of sepsis. The present review mainly focuses on the molecules and signaling pathways involved in the pathogenicity of sepsis. Additionally, several well-known natural bioactive herbal compounds and phytochemicals, which have shown protective and therapeutic effects with regard to sepsis, as well as their mechanisms of action, are presented. This review suggests that these phytochemicals are able to attenuate the overwhelming inflammatory responses developed during sepsis by modulating different signaling pathways. Moreover, the anti-inflammatory and cytoprotective activities of phytochemicals make them potent compounds to be included as complementary therapeutic agents in the diets of patients suffering from sepsis in an effort to alleviate sepsis and its life-threatening complications, such as multi-organ failure.

S-allyl cysteine, an active ingredient of garlic, attenuates acute liver dysfunction induced by lipopolysaccharide/ d-galactosamine in mouse: Underlying mechanisms

In the present study, beneficial effect of S-allyl cysteine (SAC) was evaluated in the lipopolysaccharide/d-galactosamine (LPS/d-Gal) model of acute liver injury (ALI). To mimic ALI, LPS and d-Gal (50 μg/kg and 400 mg/kg, respectively) were intraperitoneally administered and animals received SAC per os (25 or 100 mg/kg/d) for 3 days till 1 hour before LPS/d-Gal injection. Pretreatment of LPS/d-Gal group with SAC-lowered activities of alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase and partially reversed inappropriate alterations of hepatic oxidative stress- and inflammation-related biomarkers including liver reactive oxygen species, malondialdehyde, and hepatic activity of the defensive enzyme superoxide dismutase, ferric reducing antioxidant power (FRAP), toll-like receptor-4 (TLR4), cyclooxygenase 2, NLR family pyrin domain containing 3 (NLRP3), caspase 1, nuclear factor κB (NF-κB), interleukin 1β (IL-1β), IL-6, tumor necrosis factor-α, and myeloperoxidase activity. Additionally, SAC was capable to ameliorate apoptotic biomarkers including caspase 3 and DNA fragmentation. In summary, SAC can protect liver against LPS/d-Gal by attenuation of neutrophil infiltration, oxidative stress, inflammation, apoptosis, and pyroptosis which is partly linked to its suppression of TLR4/NF-κB/NLRP3 signaling.

Protective effects of hesperetin on lipopolysaccharide-induced acute lung injury in a rat model

BACKGROUND

In this experimental study, we aimed to investigate the effects of hesperetin, a natural flavonoid, on a lipopolysaccharideinduced acute lung injury model in rats.

METHODS

Between March 2019 and May 2019, a total of 18 adult male Wistar albino rats, weighing approximately 250 to 300 g, were randomly divided into three groups as control, lipopolysaccharide, and lipopolysaccharide + hesperetin groups (n=6 in each group). The wet/dry weight ratio of lung tissue was determined. Histopathological changes were examined using light and scanning electron microscopy. Pulmonary nuclear factor-kappa beta, inducible nitric oxide synthase, and alpha-smooth muscle antigen activity were determined with indirect immunohistochemical methods. Pulmonary apoptosis was detected with the terminal deoxynucleotidyl transferase dUTP nick-end labeling method. Tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6, and interleukin-10 concentrations were measured with enzyme-linked immunosorbent assay.

RESULTS

Treatment with hesperetin significantly improved the architecture of lung tissue and reduced the wet/dry weight ratio, nuclear factor-kappa beta, inducible nitric oxide synthase, and alphasmooth muscle antigen expression, pulmonary apoptosis, and levels of proinflammatory cytokines.

CONCLUSION

Our study results suggest that hesperetin has a potent protective effect against lipopolysaccharide-induced acute lung injury in rats via suppression of the proinflammatory cytokine cascade, nuclear factor-kappa beta, signaling pathway activation, and apoptosis.

S-Allyl cysteine reduces eosinophilic airway inflammation and mucus overproduction on ovalbumin-induced allergic asthma model

S-Allyl cysteine (SAC) is an active component in garlic and has various pharmacological effects, such as anti-inflammatory, anti-oxidant, and anti-cancer activities. In this study, we explored the suppressive effects of SAC on allergic airway inflammation induced in an ovalbumin (OVA)-induced asthma mouse model. To induce asthma, BALB/c mice were sensitized to OVA on days 0 and 14 by intraperitoneal injection and exposed to OVA from days 21 to 23 using a nebulizer. SAC was administered to mice by oral gavage at a dose of 10 or 20 mg/kg from days 18 to 23. SAC significantly reduced airway hyperresponsiveness, inflammatory cell counts, and Th2 type cytokines in bronchoalveolar lavage fluid induced by OVA exposure, which was accompanied by reduced serum OVA-specific immunoglobulin E. In histological analysis of the lung tissue, administration of SAC reduced inflammatory cell accumulation into lung tissue and mucus production in airway goblet cells induced by OVA exposure. Additionally, SAC significantly decreased MUC5AC expression and nuclear factor-κB phosphorylation induced by OVA exposure. In summary, SAC effectively suppressed allergic airway inflammation and mucus production in OVA-challenged asthmatic mice. Therefore, SAC shows potential for use in treating allergic asthma.

Effects of lipopolysaccharide (LPS) challenge on antioxidant capability of broiler chickens

This study was designed to investigate the effects of lipopolysaccharide (LPS) challenge on antioxidant capability (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase, GPX; and reduced glutathione to oxidized glutathione, GSH/GSSG) and induce the model of immunological stress in broiler chickens. Day-old, yellowfeathered broilers (140) were randomly assigned to 2 treatments with 7 replicates of 10 chicks each. At day 21, 23, 25 and 27, chicks were injected with LPS and blood samples were collected after 24 h. Chicks (2) from each replicate were killed, and liver and jejunum samples were collected. The activities and gene expression of SOD, CAT, and GPX, were determined. The results showed that LPS challenge reduced serum SOD at day 22 and 26, serum CAT at day 24, 26, and 28, and serum GPX at day 26. LPS challenge decreased liver SOD, liver GPX, liver GSH/GSSG ratio at day 26 and 28. LPS challenge also decreased jejunum SOD at day 26, and jejunum CAT, GPX and GSH/GSSG ratio at day 26 and 28.The expressions of liver CAT, liver GPX1, and jejunum SOD1 were down regulated at day 26. The expressions of jejunum CAT, and jejunum GPX1 were down regulated at day 26. Meanwhile, LPS reduced the expression of liver SOD1 at day 22 and the expression of jejunum GPX1 at day 28. In conclusion, three times of LPS challenge could result in serious oxidative damage and induce immune stress model.

The inhibition of inducible nitric oxide synthase and oxidative stress by agmatine attenuates vascular dysfunction in rat acute endotoxemic model

Vascular dysfunction leading to hypotension is a major complication in patients with septic shock. Inducible nitric oxide synthase (iNOS) together with oxidative stress play an important role in development of vascular dysfunction in sepsis. Searching for an endogenous, safe and yet effective remedy was the chief goal for this study. The current study investigated the effect of agmatine (AGM), an endogenous metabolite of l-arginine, on sepsis-induced vascular dysfunction induced by lipopolysaccharides (LPS) in rats. AGM pretreatment (10mg/kg, i.v.) 1h before LPS (5mg/kg, i.v.) prevented the LPS-induced mortality and elevations in serum creatine kinase-MB isoenzyme (CK-MB) activity, lactate dehydrogenase (LDH) activity, C-reactive protein (CRP) level and total nitrite/nitrate (NOx) level after 24h from LPS injection. The elevation in aortic lipid peroxidation illustrated by increased malondialdehyde (MDA) content and the decrease in aortic glutathione (GSH) and superoxide dismutase (SOD) were also ameliorated by AGM. Additionally, AGM prevented LPS-induced elevation in mRNA expression of iNOS, while endothelial NOS (eNOS) mRNA was not affected. Furthermore AGM prevented the impaired aortic contraction to KCl and phenylephrine (PE) and endothelium-dependent relaxation to acetylcholine (ACh) without affecting endothelium-independent relaxation to sodium nitroprusside (SNP).

IN CONCLUSION

AGM may represent a potential endogenous therapeutic candidate for sepsis-induced vascular dysfunction through its inhibiting effect on iNOS expression and oxidative stress.

Dexmedetomidine ameliorates the inflammatory immune response in rats with acute kidney damage

It has been demonstrated that dexmedetomidine (Dex) can protect patients with acute kidney injury from experiencing further tissue damage, however its mechanism of action remains unclear. The present study investigated the immune modulatory functions of Dex in rats with acute kidney injury (AKI) induced via injection of lipopolysaccharide into the tail vein. ELISA analysis showed that Dex reduced the levels of inflammatory cytokines in rats with AKI in a dose dependent manner. Furthermore, the regulatory effects of Dex on cytokine production disappeared when the α-2 adrenergic receptor antagonist Yohimbine (YOH) was added. For a detailed investigation on how Dex regulates the immune response in rats with AKI, the impact of Dex on the viability of splenocytes and lymphocytes was determined and it was determined that Dex did not influence splenocyte and lymphocyte viability. In addition, ELISA tests showed that Dex regulated the production of the T-helper (Th) 17 cytokines interleukin (IL)-17 and IL-23, but not the Th1 cytokine tumor necrosis factor α, in splenocytes and lymphocytes. To confirm whether Dex functioned as an α-2-adrenergic receptor in these immune regulations, YOH was administered together with Dex. When Dex and YOH were administered together, the regulatory functions of Dex were reduced, confirming that Dex acted as an agonist on the α-2-adrenergic receptor. Thus the results of the current study may provide novel insights regarding how Dex modulates immune functions in AKI.

S-Allyl cysteine alleviates inflammation by modulating the expression of NF-κB during chromium (VI)-induced hepatotoxicity in rats

Hexavalent chromium (Cr (VI)) is a common environmental pollutant. Cr (VI) exposure can lead to severe damage to the liver, but the preventive measures to diminish Cr (VI)-induced hepatotoxicity need further study. S-allyl cysteine (SAC) is a constituent of garlic ( Allium sativum) and has many beneficial effects to humans and rodents. In this study, we intended to analyze the mechanistic role of SAC during Cr (VI)-induced hepatotoxicity. Male Wistar albino rats were induced with 17 mg/kg body weight to damage the liver. The Cr (VI)-induced rats were treated with 100 mg/kg body weight of SAC as an optimum dosage to treat hepatotoxicity. We observed that the levels of oxidants, lipid peroxidation and hydroxyl radical (OH^•) were increased, and enzymatic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase were found to be decreased in Cr (VI)-induced rats. While treated with SAC, the levels of oxidants were decreased and enzymatic antioxidants were significantly ( p < 0.05) increased. Lysosomal enzyme activities were increased in Cr (VI)-induced rats and on treatment with SAC, the activities were significantly decreased. The expressions of nuclear factor-kappa B (p65-NF-κB), tumor necrosis factor α (TNF-α), and inducible nitric oxide synthase (iNOS) were increased during induction with Cr (VI). Subsequent administration of SAC to animals showed a decrease in the expressions of NF-κB, TNF-α, and iNOS. Results obtained from this study clearly demonstrated that SAC protects the liver cells from the Cr (VI)-induced free radical damage.

Maresin 1 Mitigates Inflammatory Response and Protects Mice from Sepsis

Sepsis, frequently caused by infection of bacteria, is considered as an uncontrollable systematic inflammation response syndrome (SIRS). Maresin 1 (Mar1) is a new proresolving mediator with potent anti-inflammatory effect in several animal models. However, its effect in sepsis is still not investigated. To address this question, we developed sepsis model in BALB/c mice by cecal ligation and puncture (CLP) with or without Mar1 treatment. Our data showed that Mar1 markedly improved survival rate and decreased the levels of proinflammatory cytokines in CLP mice such as interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β). Furthermore, Mar1 reduced serum level of lipopolysaccharide (LPS) and enhanced the bacteria clearance in mice sepsis model. Moreover, Mar1 attenuated lung injury and decreased level of alanine transaminase (ALT), aspartate transaminase (AST), creatinine (Cre), and blood urea nitrogen (BUN) in serum in mice after CLP surgery. Treatment with Mar1 inhibited activation of nuclear factor kappa B (NF-κb) pathway. In conclusion, Mar1 exhibited protective effect in sepsis by reducing LPS, bacteria burden in serum, inhibiting inflammation response, and improving vital organ function. The possible mechanism is partly involved in inhibition of NF-κb activation.

A novel imidazopyridine derivative, X22, attenuates sepsis-induced lung and liver injury by inhibiting the inflammatory response in vitro and in vivo

Sepsis remains a leading cause of death worldwide. Despite years of extensive research, effective drugs to treat sepsis in the clinic are lacking. In this study, we found a novel imidazopyridine derivative, X22, which has powerful anti-inflammatory activity. X22 dose-dependently inhibited lipopolysaccharide (LPS)-induced proinflammatory cytokine production in mouse primary peritoneal macrophages and RAW 264.7 macrophages. X22 also downregulated the LPS-induced proinflammatory gene expression in vitro. In vivo, X22 exhibited a significant protection against LPS-induced death. Pretreatment or treatment with X22 attenuated the sepsis-induced lung and liver injury by inhibiting the inflammatory response. In addition, X22 showed protection against LPS-induced acute lung injury. We additionally found that pretreatment with X22 reduced the inflammatory pain in the acetic acid and formalin models and reduced the dimethylbenzene-induced ear swelling and acetic acid-increased vascular permeability. Together, these data confirmed that X22 has multiple anti-inflammatory effects and may be a potential therapeutic option in the treatment of inflammatory diseases.

Chilean Strawberry Consumption Protects against LPS-Induced Liver Injury by Anti-Inflammatory and Antioxidant Capability in Sprague-Dawley Rats

The Chilean strawberry fruit has high content of antioxidants and polyphenols. Previous studies evidenced antioxidant properties by in vitro methods. However, the antioxidant effect and its impact as functional food on animal health have not been evaluated. In this study, rats were fed with a Chilean strawberry aqueous extract (4 g/kg of animal per day) and then subjected to LPS-induced liver injury (5 mg/kg). Transaminases and histological studies revealed a reduction in liver injury in rats fed with strawberry aqueous extract compared with the control group. Additionally, white strawberry supplementation significantly reduced the serum levels and gene expression of TNF-α, IL-6, and IL-1β cytokines compared with nonsupplemented rats. The level of F2-isoprostanes and GSH/GSSG indicated a reduction in liver oxidative stress by the consumption of strawberry aqueous extract. Altogether, the evidence suggests that dietary supplementation of rats with a Chilean white strawberry aqueous extract favours the normalization of oxidative and inflammatory responses after a liver injury induced by LPS.

Dexmedetomidine protects against acute kidney injury through downregulating inflammatory reactions in endotoxemia rats

Approximately 42% of patients with sepsis undergo acute kidney injury (AKI), which evidently influences patient survival. However, effective therapy strategies are lacking, thus, the present study investigated the protective effects of dexmedetomidine (DEX), a highly selective α-2 adrenoceptor agonist, in rat sepsis models. Rat sepsis models were generated through lipopolysaccharide injection (LPS; 5 mg/kg) in the tail vein. Rats were pretreated with DEX (10 µg/kg) 10 min before LPS injection to observe its protective effects. Of note, a unique α-2-adrenergic receptor antagonist, yohimbine (YOH; 1 mg/kg, intraperitoneally), was also used to antagonize the protective effects of DEX 30 min before DEX exposure. Thirty-two male Sprague Dawley rats were randomly divided into the Sham, LPS, DEX + LPS and YOH + DEX + LPS groups (n=8/group). All the rats were sacrificed 4 h later to observe the pathological changes of renal tissue, including plasma creatinine (Cr), blood urea nitrogen (BUN), kidney injury molecule-1 (KIM-1) and high mobility group protein 1 (HMGB-1) expression. Interleukin 6 (IL-6), IL-18 and tumor necrosis factor α (TNF-α) were all determined to examine the mechanisms of LPS-induced AKI relative to inflammatory reaction. The results indicated that AKI induced by LPS was serious. Renal pathological injury, plasma Cr, BUN, IL-6, IL-18 and TNF-α were all evidently increased in varying degrees. KIM-1 and HMGB-1 expression was upregulated in the LPS group (P<0.05 vs. Sham group). However, when rats were pretreated with DEX, AKI induced by LPS was decreased significantly. Renal pathological injury, plasma Cr, BUN, IL-6, IL-18, TNF-α, and KIM-1 and HMGB-1 expression were all reduced (P<0.05 vs. LPS group). In addition, exposure of the α-2-adrenergic receptor antagonist, YOH, eliminated this reduction. In conclusion, DEX protected against sepsis-induced AKI through depressing the inflammatory reaction, mechanisms of which may be associated with α-2 receptors inhibition.