Protective effect of kaempferol glucoside against lipopolysaccharide-caused acute lung injury via targeting Nrf2/NF-κB/NLRP3/GSDMD: Integrating experimental and computational studies.

The current study explored the protective potential of kaempferol 3-sophoroside-7-glucoside (KSG) against acute lung injury (ALI). Pre-treatment with KSG effectively secured mice from ALI and showed similar efficaciousness to dexamethasone. KSG markedly increased the survival rate and alleviated lung pathological lesions induced by lipopolysaccharide (LPS). Furthermore, KSG attenuated differential and total cell counts in BALF (bronchoalveolar lavage fluid) and MPO (myeloperoxidase) activity. KSG counteracted the NF-κB (nuclear factor-κB) activation and significantly ameliorated the downstream inflammatory cytokine, TNF-α (tumor necrosis factor-α). Simultaneously, KSG suppressed the over-expression of NLRP3 (NOD-like receptor protein 3), caspase-1, and pro-inflammatory cytokine interleukin IL-1ß (interleukine-1ß) and prohibited the elevation of the pyroptotic parameter GSDMD-N (N-terminal domain of gasdermin D) induced by LPS challenge. In addition, KSG significantly enhanced Nrf2 (nuclear-factor erythroid-2-related factor) and HO-1 (heme-oxygenase-1) expression. Meanwhile, KSG mitigated lipid peroxidative markers (malondialdehyde, protein carbonyl and 4-hydroxynonenal) and boosted endogenous antioxidants (superoxide dismutase/reduced glutathione/catalase) in lung tissue. In silico analyses revealed that KSG disrupts Keap1-Nrf2 protein-protein interactions by binding to the KEAP1 domain, consequently activating Nrf2. Specifically, molecular docking demonstrated superior binding affinity of KSG to KEAP1 compared to the reference inhibitor, with docking scores of -9.576 and -6.633 Kcal/mol, respectively. Additionally, the MM-GBSA binding free energy of KSG (-67.25 Kcal/mol) surpassed that of the reference inhibitor (-56.36 Kcal/mol). Furthermore, MD simulation analysis revealed that the KSG-KEAP1 complex exhibits substantial and stable binding interactions with various amino acids over a duration of 100 ns. These findings showed the protective anti-inflammatory and anti-oxidative modulatory efficiencies of KSG that effectively counteracted LPS-induced ALI and encouraged future research and clinical applications of KSG as a protective strategy for ALI.

Modulation of the crosstalk between Keap1/Nrf2/HO-1 and NF-κB signaling pathways by Tomatidine protects against inflammation/oxidative stress-driven fulminant hepatic failure in mice.

Fulminant hepatic failure (FHF) is the terminal phase of acute liver injury, which is characterized by massive hepatocyte necrosis and rapid hepatic dysfunction in patients without preexisting liver disease. There are currently no therapeutic options for such a life-threatening hepatic failure except liver transplantation; therefore, the terminal phase of the underlying acute liver injury should be avoided. Tomatidine (TOM), asteroidal alkaloid, may have different biological activities, including antioxidant and anti-inflammatory effects. Herein, the lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced FHF mouse model was established to explore the protective potential of TOM and the underlying mechanisms of action. TOM pretreatment significantly inhibited hepatocyte necrosis and decreased serum aminotransferase activities in LPS/D-GalN-stimulated mice. TOM further increased the level of different antioxidant enzymes while reducing lipid peroxidation biomarkers in the liver. These beneficial effects of TOM were shown to be associated with targeting of NF-κB signaling pathways, where TOM repressed NF-κB activation and decreased LPS/D-GalN-induced TNF-α, IL-6, IL-1ß, and iNOS production. Moreover, TOM prevented LPS/D-GalN-induced upregulation of Keap1 expression and downregulation of Nrf2 and HO-1 expression, leading to increased Nrf2-binding activity and HO-1 levels. Besides, TOM pretreatment repressed LPS/D-GalN-induced upregulation of proliferating cell nuclear antigen (PCNA) expression, which spared the hepatocytes from damage and subsequent repair following the LPS/D-GalN challenge. Collectively, our findings revealed that TOM has a protective effect on LPS/D-GalN-induced FHF in mice, showing powerful antioxidant and anti-inflammatory effects, primarily mediated via modulating Keap1/Nrf2/HO-1 and NF-κB/TNF-α/IL-6/IL-1ß/iNOS signaling pathways.

SIRT1/Nrf2/NF-κB Signaling Mediates Anti-Inflammatory and Anti-Apoptotic Activities of Oleanolic Acid in a Mouse Model of Acute Hepatorenal Damage.

Background and objectives: Oleanolic acid (OA) is a penta-cyclic triterpene with diverse bioactivities such as anticarcinogenic, antiviral, antimicrobial, hepatoprotective, anti-atherosclerotic, hypolipidemic, and gastroprotective. However, its effects on hepatorenal damage remain unclear. The protective activity of OA, separated from Viscum schimperi (Loranthaceae), against TAA (thioacetamide)-produced acute hepatic and renal damage was explored. Materials and Methods: Mice were treated with OA for 7 days before TAA (200 mg/kg, i.p.). Serum indices of hepatorenal injury, pathological lesions, molecular biological indexes, and inflammatory/apoptotic genes were estimated. Results: The tissues of both organs were greatly affected by the TAA injection. That was evident through increased serum markers of hepato-renal injury as well as remarkable histopathological lesions. TAA-induced injury was associated with oxidative and inflammatory responses in both organs as there was an elevation of oxidative stress parameters (4-HNE (4-hydroxy-nonenal), MDA (malondialdehyde), NOx (nitric oxide)), decline of antioxidants (reduced glutathione (GSH), superoxide dismutase (SOD), and total antioxidant capacity (TAC)), and an increase in the gene expression/level of inflammatory mediators (interleukins (1ß&6)). The inflammatory response was linked to a significant activation of NF-κB (nuclear-factor kappa-B)/TNF-α (tumor-necrosis factor-alpha) signaling. The inflammatory response in both organs was accompanied by apoptotic changes, including a rise in the gene expression and level of apoptotic parameters (caspase-3 and Bax) along with a decline in Bcl-2 (anti-apoptotic parameter) gene expression and level. These pathogenic events were found to be closely related to the suppression of the antioxidant signaling pathway, Nrf2 (nuclear-factor erythroid 2-related factor-2)/SIRT1 (sirtuin-1)/HO-1 (heme-oxygenase 1). On the other hand, OA significantly ameliorated TAA-induced injury in both organs. On the other hand, OA counterpoised the inflammatory response as it ameliorated NF-κB/TNF-α signaling and cytokine release. OA enhanced Nrf2/SIRT1/HO-1 signaling and counteracted apoptotic damage. Conclusions: OA showed anti-inflammation and antiapoptotic capacities that effectively suppressed TAA-induced acute hepatorenal damage.

Cepabiflas B and C as Novel Anti-Inflammatory and Anti-Apoptotic Agents against Endotoxin-Induced Acute Kidney and Hepatic Injury in Mice: Impact on Bax/Bcl2 and Nrf2/NF-κB Signalling Pathways.

Cepabiflas B and C (CBs) are flavonoid dimers separated from Allium cepa. They demonstrated antioxidant and α-glucosidase and protein tyrosine phosphatase 1B inhibition capacities. However, their anti-inflammatory activities and their effects on endotoxemia are unknown. The current study aimed at exploring the protective activities of CBs on lipopolysaccharide (LPS)-induced kidney and liver damage in mice and investigating the possible molecular mechanisms. Mice were orally treated with a low (40 mg/kg) or high (60 mg/kg) dose of CBs for five days prior to a single intraperitoneal injection of LPS (10 mg/kg). Samples of serum and hepatic and kidney tissues were collected 24 h after the LPS challenge. Changes in serum indices of hepatic and renal injury, pathological changes, molecular biological parameters, and proteins/genes related to inflammation and apoptosis of these organs were estimated. LPS injection resulted in deleterious injury to both organs as indicated by elevation of serum ALT, AST, creatinine, and BUN. The deteriorated histopathology of hepatic and renal tissues confirmed the biochemical indices. CBs treated groups showed a reduction in these parameters and improved histopathological injurious effects of LPS. LPS-induced hepatorenal injury was linked to elevated oxidative stress as indicated by high levels of MDA, 4-HNE, as well as repressed antioxidants (TAC, SOD, and GSH) in hepatic and kidney tissues. This was accompanied with suppressed Nrf2/HO-1 activity. Additionally, there was a remarkable inflammatory response in both organs as NF-κB signalling was activated and high levels of downstream cytokines were produced following the LPS challenge. Apoptotic changes were observed as the level and gene expression of Bax and caspase-3 were elevated along with declined level and gene expression of Bcl2. Interestingly, CBs reversed all these molecular and genetic changes and restricted oxidative inflammatory and apoptotic parameters after LPS-injection. Collectedly, our findings suggested the marked anti-inflammatory and anti-apoptotic activity of CBs which encouraged its use as a new candidate for septic patients.

γ-Mangostin abrogates AINT-induced cholestatic liver injury: Impact on Nrf2/NF-κB/NLRP3/Caspase-1/IL-1ß/GSDMD signalling.

γ-Mangostin (γ-MN) is one of the abundant xanthones separated from Garcinia mangostana (Clusiaceae) pericarps that has been reported to have varied bioactivities such as neuroprotective, cytotoxic, antihyperglycemic, antioxidant, and anti-inflammation. Yet, its effect on cholestatic liver damage (CLI) has not been investigated. This study explored the protective activity of γ-MN against alpha-naphthyl isothiocyanate (ANIT)-induced CLI in mice. The results showed that γ-MN protected against ANIT-induced CLI as indicated by reduced serum levels of hepatic injury parameters (e.g., ALT, AST, γ-GT, ALP, LDH, bilirubin, and total bile acids). ANIT-induced pathological lesions were improved in γ-MN pre-treated groups. γ-MN exerted potent antioxidant effects as it lowered the parameters of lipid peroxidation (4-HNE, PC, and MDA) and intensified the content and activity of antioxidants (TAC, GSH, GSH-Px, GST, and SOD) in the hepatic tissue. Furthermore, γ-MN enhanced the signalling of Nrf2/HO-1 as it augmented the mRNA expression of Nrf2/downstream genes (HO-1/GCLc/NQO1/SOD). The binding capacity and the immuno-expression of Nrf2 were also increased. γ-MN showed anti-inflammatory capacity as it suppressed the activation of NF-κB signalling, it decreased mRNA expression and levels of NF-κB/TNF-α/IL-6 and the immuno-expression of NF-κB/TNF-α. In addition, γ-MN inhibited the activation of NLRP3 inflammasome as it lowered the mRNA expression of NLRP3/caspase-1/IL-1ß along with their levels as well as the immuno-expression of caspase-1/IL-1ß. γ-MN also reduced the level of the pyroptotic parameter GSDMD. Collectively, this study demonstrated the potent hepatoprotective potential of γ-MN against CLI which was linked to its ability to potentiate Nrf2/HO-1 and to offset NF-κB/NLRP3/Caspase-1/IL-1ß/GSDMD. Hence, γ-MN may be suggested as a new candidate for cholestatic patients.

IL-6 at the center of cytokine storm: Circulating inflammation mediators as biomarkers in hospitalized COVID-19 patients.

INTRODUCTION: The management of hospitalized COVID-19 patients depends largely on controlling the intensified inflammatory response known as the cytokine storm. Candidate inflammatory cytokines can serve as new biomarkers for the management of hospitalized COVID-19 patients. METHODS: Patients (80) were recruited into three groups: room air (RA), oxygen (OX) and mechanical ventilator (MV). Blood analysis was performed for RBC, WBC, Hb, Platelets, serum albumin and creatinine, INR, PTT, and hematocrit. ELISA was used to quantify a panel of inflammatory mediators including GM-SCF, IFN-α, IFNγ, IL-1ß, IL-1R, IL-2, IL-2Ra, IL-6, IL-8, IL-10, IL-12p70, IL-13, MCP-1, MIP-1a, and TNF-α. Correlations between laboratory results and the levels of circulating inflammation mediators were investigated. RESULTS: Patients on MV had low RBC, Hb, albumin, and HCT and high WBC count, PTT, and INR when compared to RA and OX groups. A statistical positive correlation was found between WBC and the levels of IL-6 and MCP-1. RBCs correlated negatively with IL-6 and IL-10 and positively with IL-8. Higher TNF-α correlated with lower platelet counts while higher levels of IL-1Rα and IL-10 were associated with lower Hb levels. Increases in IFN-γ and TNF-α were indicative of compromised kidney functions as creatinine levels increased significantly. Most significant correlations were found between IL-6 and lab results, showing positive correlation with WBC and INR, and negative correlation with RBC, albumin, and HCT. CONCLUSIONS: Having the most significant correlations, IL-6 high levels in mechanically ventilated patients were shown to affect laboratory results, and, therefore, is suggested as a severity biomarker of COVID-19.

Structure-Based Virtual Screening and Molecular Dynamics Simulation Assessments of Depsidones as Possible Selective Cannabinoid Receptor Type 2 Agonists.

The discovery of natural drug metabolites is a leading contributor to fulfilling the sustainable development goal of finding solutions to global health challenges. Depsidones are a class of polyketides that have been separated from lichens, fungi, sponges, and plants and possess various bioactivities, including cytotoxic, antimicrobial, antimalarial, antituberculosis, acetylcholinesterase and α-glucosidase inhibition, and anti-inflammatory effects. Endocannabinoid receptors (CB1 and CB2) are G-protein-coupled receptors (GPCRs), and their activation mediates many physiological processes. CB1 is the dominant subtype in the central nervous system, while CB2 is mainly expressed in the immune system. The two receptors exhibit high heterogeneity, making developing selective ligands a great challenge. Attempts to develop CB2 selective agonists for treating inflammatory diseases and neuropathic pain have not been successful due to the high homology of the binding sites of the CB receptors. In this work, 235 depsidones from various sources were investigated for the possibility of identifying CB2-selective agonists by performing multiple docking studies, including induced fit docking and Prime/molecular mechanics-generalized Born surface area (MM-GBSA) calculations to predict the binding mode and free energy. Simplicildone J (10), lobaric acid (110), mollicellin Q (101), garcinisidone E (215), mollicellin P (100), paucinervin Q (149), and boremexin C (161) had the highest binding scores (-12.134 kcal/mol, -11.944 kcal/mol, -11.479 kcal/mol, -11.394 kcal/mol, -11.322 kcal/mol, -11.305 kcal/mol, and -11.254 kcal/mol, respectively) when screened against the CB2 receptor (PDB ID: 6KPF). The molecular dynamic simulation was performed on the compounds with the highest binding scores. The computational outcomes show that garcinisidone E (215) and paucinervin Q (149) could be substantial candidates for CB2 receptor activation and warrant further in vivo and in vitro investigations.

Cytokine Profiling among Children with Multisystem Inflammatory Syndrome versus Simple COVID-19 Infection: A Study from Northwest Saudi Arabia.

BACKGROUND: Multisystem Inflammatory Syndrome in Children (MIS-C) is a novel syndrome associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with varying clinical features. This study aimed to analyze the expression profiles of cytokines in blood, report the important clinical characteristics, and correlate these with the short- and mid-term outcomes. METHODS: This cross-sectional study was conducted on hospitalized children with MIS-C from March 2021 to May 2022. Phenotypes were classified into two groups (A,B) according to the severity of the disease and the need for invasive respiratory support. Clinical features, laboratory parameters, and outcomes were reported. RESULTS: We identified 60 children with MIS-C (mean age of 7.4 ± 3.8 years) compared to 30 age- and sex-matched controls with simple COVID-19. The clinical manifestations of MIS-C patients were fever (100%), respiratory (83.3%), GIT (80%), and conjunctivitis (80%). Twenty-seven MIS-C children (45%) required PICU admission due to shock and needed mechanical ventilation. Anemia, lymphopenia, and elevated levels of inflammatory and tissue injury markers were observed in the MIS-C groups (mainly B). High cytokine levels (IL-1ß, IL-6, IFN-α, GM-CSF, and HMGB1) were observed acutely in the MIS-C children, and a persistent elevation of some cytokines were reported at midterm follow-up, especially in Group B. CONCLUSION: Robust inflammatory response to COVID-19 disease with elevated IL-1ß, IL-6, and GM-CSF levels might explain the severity and outcome of the clinical syndrome.

Alpha-Mangostin as a New Therapeutic Candidate for Concanavalin A-Induced Autoimmune Hepatitis: Impact on the SIRT1/Nrf2 and NF-κB Crosstalk.

Alpha-mangostin (α-MN) is a xanthone obtained from Garcinia mangostana that has diverse anti-oxidative and anti-inflammatory potentials. However, its pharmacological activity against autoimmune hepatitis (AIH) has not been investigated before. Concanavalin A (Con A) was injected into mice to induce AIH and two doses of α-MN were tested for their protective effects against Con A-induced AIH. The results demonstrated the potent hepatoprotective activity of α-MN evidenced by a remarkable decrease of serum indices of the hepatic injury and amendment of the histological lesions. α-MN significantly attenuated the level and immuno-expression of myeloperoxidase (MPO) indicating a decrease in the neutrophil infiltration into the liver. Additionally, the recruitment of the CD4+ T cell was suppressed in the α-MN pre-treated animals. α-MN showed a potent ability to repress the Con A-induced oxidative stress evident by the reduced levels of malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), and protein carbonyl (PC), as well as the enhanced levels of antioxidants as the reduced glutathione (GSH), superoxide dismutase (SOD), and total antioxidant capacity (TAC). The ELISA, RT-PCR, and IHC analyses revealed that α-MN enhanced the sirtuin1/nuclear factor erythroid 2 related factor-2 (SIRT1/Nrf2) signaling and its downstream cascade genes concurrently with the inhibition of the nuclear factor kappa B (NF-κB) and the inflammatory cytokines (tumor necrosis factor-alpha and interleukine-6) signaling. Taken together, these results inferred that the hepatoprotective activity of α-MN could prevent Con A-induced AIH through the modulation of the SIRT1/Nrf2/NF-κB signaling. Hence, α-MN may be considered as a promising candidate for AIH therapy.

Cucurbitacin E glucoside alleviates concanavalin A-induced hepatitis through enhancing SIRT1/Nrf2/HO-1 and inhibiting NF-ĸB/NLRP3 signaling pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Cucurbitacins are highly oxygenated tetracyclic triterpenoids, that represent the major metabolites reported from C. colocynthis (L.) Schrad.. Cucurbitacin E glucoside (CuE) is a tetracyclic triterpene glycoside separated from Cucurbitaceae plants. CuE has potent anti-inflammatory, immunomodulatory, and anti-tumor properties. AIM OF THE STUDY: The current study aimed at examining the hepatoprotective effect of CuE against concanavalin A (Con A)-produced hepatitis. MATERIALS AND METHODS: Mice were intravenously administered Con A (15 mg/kg) to induce AIH. CuE was orally administered at two different doses for five days preceding Con A injection. RESULTS: The results revealed that CuE pretreatment markedly attenuated the serum indices of hepatotoxicity and the severity of hepatic lesions. CuE depressed Con A-provoked increment in CD4+ T-cells in hepatic tissue. The antioxidant activity of CuE was evident through its ability to decrease markers of Con A-induced oxidative stress (malondialdehyde, 4-hydroxyenonanal, and protein carbonyl) and intensified the antioxidants in the hepatic tissue (SOD, GSH, and TAC). CuE increased mRNA expression of SIRT1 and Nrf2 as well as its binding capacity. Subsequently, CuE augmented mRNA expression of Nrf2 targeted genes as NQO1, GCL, and HO-1 and recovered its normal level. CuE inhibited the activation of NF-κB/downstream pro-inflammatory mediators signaling. Furthermore, CuE attenuated the mRNA expression of NLRP3 and its associated genes. CONCLUSION: Collectively, these results demonstrated the remarkable hepatoprotective potential of CuE towards Con A-induced AIH which was mediated via suppression of oxidative stress, enhancing SIRT1/Nrf2/HO-1, and prohibition of the NF-κB/NLRP3 signaling. CuE could be a candidate for hepatitis patients.

Garcinone E Mitigates Oxidative Inflammatory Response and Protects against Experimental Autoimmune Hepatitis via Modulation of Nrf2/HO-1, NF-κB and TNF-α/JNK Axis.

Garcinia mangostana L. (Clusiaceae), a popular tropical fruit for its juiciness and sweetness, is an opulent fountain of prenylated and oxygenated xanthones with a vast array of bio-activities. Garcinone E (GE), a xanthone derivative reported from G. mangostana, possesses cytotoxic and aromatase inhibitory activities. The present research endeavors to investigate the hepato-protection efficaciousness of GE on concanavalin-A (Con-A)-instigated hepatitis. Results showed that GE pretreating noticeably diminishes both the serum indices (transaminases, ALP, LDH, and γ-GT) and histopathological lesions of the liver. It counteracted neutrophil and CD4+ infiltration into the liver. GE furthered the Nrf2 genetic expression and its antioxidants' cascade, which resulted in amelioration of Con-A-caused oxidative stress (OS), lipid per-oxidative markers (4-HNE, MDA, PC) reduction, and intensified antioxidants (TAC, SOD, GSH) in the hepatic tissue. Additionally, GE prohibited NF-ĸB (nuclear factor kappa-B) activation and lessened the genetics and levels of downstream cytokines (IL1ß and IL6). Moreover, the TNF-α/JNK axis was repressed in GE-treated mice, which was accompanied by attenuation of Con-A-induced apoptosis. These findings demonstrated the protective potential of GE in Con-A-induced hepatitis which may be associated with Nrf2/HO-1 signaling activation and OS suppression, as well as modulation of the NF-κB and TNF-α/JNK/apoptosis signaling pathway. These results suggest the potential use of GE as a novel hepato-protective agent against autoimmune hepatitis.

Terretonin as a New Protective Agent against Sepsis-Induced Acute Lung Injury: Impact on SIRT1/Nrf2/NF-κBp65/NLRP3 Signaling.

Endophytic fungi are proving to be an excellent source of chemical entities with unique structures and varied bioactivities. Terretonin (TE) and its structurally related derivatives are a class of meroterpenoids, possessing the same unique tetracyclic core skeleton, which have been reported from the Aspergillus genus. This study was carried out to assess the potential protective effects of TE separated from the endophytic fungus A. terreus against LPS (lipopolysaccharide)-induced ALI (acute lung injury) in mice. The results revealed that TE alleviated pulmonary edema as it lowered both the W/D lung ratio and protein content. The inflammatory response represented by inflammatory cell infiltration into the lung tissues was greatly repressed by TE. That was supported by the improved histopathological results and also by the reduced level of myeloperoxidase in the lung. TE showed a potent antioxidant activity as it attenuated lipid peroxidative markers (malondialdehyde, 4-hydroxynonenal, and protein carbonyl) and enhanced endogenous antioxidants (reduced glutathione, superoxide dismutase, and catalase) in lung tissues. Similarly, TE increased the mRNA expression of SIRT1, Nrf2, and its genes (HO-1, NQO1, and GCLm). On the other hand, TE restrained the activation of NF-κB (nuclear factor-κB) in the lung. Consequently, TE depressed the pro-inflammatory cytokines: nitric oxide (NOx), TNF-α (tumor necrosis factor-α), and interleukins (IL-6 and -1ß). Additionally, TE inhibited NLRP3 signaling and interrupted apoptosis by decreasing the levels of proapoptotic markers (Bax and caspase-3) and increasing the level of an anti-apoptotic marker (Bcl-2). In conclusion, TE had a remarkable protective potential on LPS-induced lung damage via antioxidant and anti-inflammatory mechanisms. This finding encourages further investigations on this promising candidate.

Kirenol: A promising bioactive metabolite from siegesbeckia species: A detailed review.

ETHNOPHARMACOLOGICAL RELEVANCE: Kirenol (Kr) is an ent-pimarane type diterpenoid that has been reported from Siegesbeckiaorientalis, S. pubescens, and S. glabrescens (family Asteraceae). These plants have been used traditionally for treating various ailments such as hypertension, neurasthenia, rheumatoid arthritis, asthma, snakebites, allergic disorders, paralysis, soreness, cutaneous disorders, rubella, menstrual disorders, numbness of limbs, dizziness, headache, and malaria. Importantly, in recent years, Kr has received great attention due to its diversified pharmacological activities. AIM OF THE STUDY: The current work aims to give an overview on the reported pharmacological activities of Kr. Furthermore, the findings regarding its methods for extraction, quantitative analysis, purification, pharmacokinetics, pharmaceutical and food preparations, biosynthesis, identification, semisynthetic analogues, and toxicity are highlighted to provide a reference and perspective for its further investigation. METHODS: Electronic databases including ScienceDirect, Web of Knowledge, SCOPUS, Wiley Online Library, Taylor & Francis, PubMed, Springer, JACS, and Google Scholar were searched up to the beginning of 2021 to identify the reported studies. RESULTS: A total of 93 articles have been reviewed. The reported data suggested that Kr possessed various bioactivities including cytotoxic, apoptotic, anticancer, anti-inflammatory, cardio-protective, anti-photo-aging, anti-adipogenic, antimicrobial, muscle function improvement, fracture and wound healing, and anti-arthritic. In addition, studies revealed that the antioxidative and anti-inflammatory activities of Kr may mediate many of its therapeutic potentials as confirmed by several in-vitro and in-vivo studies. CONCLUSION: This review provides an updated summary of the recent studies on Kr, including methods for extraction, quantitative analysis, purification, pharmacokinetics, pharmaceutical and food preparations, biosynthesis, and identification, as well as semisynthetic analogues, pharmacological activities, and toxicity. Thus, this work can provide useful considerations for planning and design future research on Kr.

Anti-fibrotic activity of sitagliptin against concanavalin A-induced hepatic fibrosis. Role of Nrf2 activation/NF-κB inhibition.

Sitagliptin is known for its anti-diabetic activity though it has other pleiotropic pharmacological actions. Its effect against concanavalin A (Con A)-induced hepatic fibrosis has not been investigated yet. Our target was to test whether sitagliptin can suppress the development of Con A-induced hepatic fibrosis and if so, what are the mechanisms involved? Con A (6 mg/kg) was injected once weekly to male Swiss albino mice for four weeks. Sitagliptin was daily administered concurrently with Con A. Results have shown the potent hepatoprotective activity of sitagliptin against Con A-induced hepatitis and fibrosis. That was evident through the amelioration of hepatotoxicity serum parameters (ALT, AST, ALP, and LDH) and the increase in the level of serum albumin in sitagliptin treated mice. Simultaneously, there was amendment of the Con A-induced hepatic lesions and repression of fibrosis in sitagliptin-treated animals. Hydroxyproline, collagen content and the immuno-expression of the fibrotic markers, TGF-ß and α-SMA were depressed upon sitagliptin treatment. Sitagliptin suppressed Con A-induced oxidative stress and increased antioxidants. RT-PCR analysis showed enhancement of mRNA expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its target genes (GCLc, GCLm, NQO-1, HO-1) by sitagliptin. Furthermore, sitagliptin ameliorated the level and immuno-expression of nuclear factor kappa-B (NF-κB) alongside the immuno-expression of the inflammatory cytokine, TNF-α. Taken together, this study demonstrates the hepatoprotective activity of sitagliptin which may be in part related to enhancement of Nrf2 signaling pathway and inhibition of NF-κB which interact inflammatory response in liver. Sitagliptin might be a new candidate to suppress hepatitis-associated fibrosis.

Euphorbia cuneata Represses LPS-induced Acute Lung Injury in Mice via its Antioxidative and Anti-inflammatory Activities.

Euphorbia cuneata (EC; Euphorbiaceae), which widely grows in Saudi Arabia and Yemen, is used traditionally to treat pain and inflammation. This study aimed to evaluate the protective anti-inflammatory effect of a standardized extract of EC against lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice and the possible underlying mechanism(s) of this pharmacologic activity. ALI was induced in male Balb/c mice using intraperitoneal injection of LPS. A standardized total methanol extract of EC or dexamethasone was administered 5 days prior to LPS challenge. Bronchoalveolar fluid (BALF) and lung samples were collected for analysis. The results demonstrated the protective anti-inflammatory effect of EC against LPS-induced ALI in mice. Standardized EC contained 2R-naringenin-7-O-ß-glucoside (1), kaempferol-7-O-ß-glucoside (2), cuneatannin (3), quercetin (4), and 2R-naringenin (5) in concentrations of 6.16, 4.80, 51.05, 13.20, and 50.00 mg/g of extract, respectively. EC showed a protective effect against LPS-induced pulmonary damage. EC reduced lung wet/dry weight (W/D) ratio and total protein content in BALF, indicating attenuation of the pulmonary edema. Total and differential cell counts were decreased in EC-treated animals. Histopathological examination confirmed the protective effect of EC, as indicated by an amelioration of LPS-induced lesions in lung tissue. EC also showed a potent anti-oxidative property as it decreased lipid peroxidation and increased the antioxidants in lung tissue. Finally, the anti-inflammatory activity of EC was obvious through its ability to suppress the activation of nuclear factor-κB (NF-κB), and hence its reduction of the levels of downstream inflammatory mediators. In conclusion, these results demonstrate the protective effects of EC against LPS-induced lung injury in mice, which may be due to its antioxidative and anti-inflammatory activities.

Protective anti-inflammatory activity of tovophyllin A against acute lung injury and its potential cytotoxicity to epithelial lung and breast carcinomas.

Tovophyllin A (TA) is a xanthone isolated from Garcinia mangostana L. (GM, Guttiferae) pericarps that possesses various beneficial bioactivities. However, its protective effects on acute lung injury (ALI) and lung carcinoma have not yet been explored. The current work was designed to investigate the protective potential of TA against ALI and explore the possible mechanism of action. Two different doses of TA were tested against lipopolysaccharide (LPS)-induced ALI in mice. Moreover, the cytotoxic potential of TA was assessed in epithelial lung (A549 cells) and breast (MCF7 cells) carcinomas utilizing a sulforhodamine B (SRB) assay. The results revealed that TA possessed the ability to protect against LPS-induced acute lung damage. TA attenuated LPS-induced pulmonary edema, as it lowered the protein content in the bronchoalveolar lavage fluid (BALF) and the lung W/D ratio. In addition, TA counteracted inflammatory cell infiltration into the lung tissue, as shown by the total and differential cell counts in the BALF and histopathological examination of the lungs. The oxidative burden in the pulmonary tissue was ameliorated in TA-treated animals as there were reductions in the malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) levels in the lung tissue. TA increased the levels of antioxidants such as reduced glutathione (GSH) and superoxide dismutase (SOD) in the lungs. Furthermore, TA inhibited the activation of nuclear factor-κB (NF-κB). In addition, TA had potent anti-inflammatory activity as it reduced the immunoexpression and levels of the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß and IL-6. Furthermore, TA showed significantly enhanced cytotoxic activity against the MCF-7 and A549 cell lines with IC50s of 6.1 and 2.2 µM, respectively, compared to doxorubicin (IC50s of 0.41 and 0.74 µM, respectively). In conclusion, TA ameliorates LPS-induced ALI through the suppression of oxidative stress and inflammation. These findings suggest the potential use of this compound as a future treatment for ALI.

Protective role of pirfenidone against experimentally-induced pancreatitis.

BACKGROUND: Pirfenidone (PFD) is an orally active antifibrotic agent that has anti-inflammatory activity in diverse animal models. Its effect against acute pancreatitis (AP) has not been elucidated. Hence, the present investigation was carried out to assess the potential protective role of PFD against l-arginine-induced AP in mice. METHODS: AP was induced in adult male Swiss albino mice via intraperitoneal injections of l-arginine (4 g/kg, twice each 1 h apart). PFD (250 mg/kg, orally) was administered one day before and on the day of l-arginine challenge. Twenty-four hours after l-arginine injection, the severity of AP was evaluated using biochemical and histological analyses. Indices of oxidative stress, inflammation and apoptosis were evaluated using ELISA and immunohistochemistry (IHC). RESULTS: PFD suppressed the development of l-arginine-induced AP as revealed by the improvement of histopathological lesions of pancreatic specimen and the significant reduction of serum amylase and lipase levels. Notably, PFD reduced the lipid peroxidation and enhanced the antioxidants such as reduced glutathione (GSH) and superoxide dismutase (SOD) in pancreatic tissue. Importantly, PFD suppressed AP-associated elevation of inflammatory cytokines along with depression of nuclear factor kappa-B (NF-κB) immuno-expression in pancreatic tissue. Lastly, PFD efficiently ameliorated AP-induced elevation of the pro-apoptotic protein (Bax) and increased AP-induced reduction of the anti-apoptotic protein (Bcl2). CONCLUSIONS: PFD protected against l-arginine-induced AP in mice through anti-oxidative, anti-inflammatory and anti-apoptotic properties.

Aspernolide F, as a new cardioprotective butyrolactone against doxorubicin-induced cardiotoxicity.

Endophytic fungi have known as a promising source of secondary metabolites. γ-Butyrolactones are a class of metabolites reported from Aspergillus genus, which attracted much attention for their bioactivities. This study aimed to assess the potential cardioprotective effects of aspernolide F (AF) separated from the endophytic fungus A. terreus against doxorubicin (DOX)-induced cardiotoxic effects in rats. Animals were treated with two different doses of AF for 10 days prior to DOX injection. Electrocardiographic (ECG), biochemical, histopathological and immunohistochemical analyses were performed. Results have shown that AF effectively protected against DOX-induced cardiac damage as AF counteracted DOX-induced ECG abnormalities and attenuated serum markers of cardiotoxicity (creatine kinase-MB, lactate dehydrogenase, troponin I, and troponin T). Histopathological examination of cardiac tissue revealed a remarkable improvement in DOX-induced lesions. In addition, AF ameliorated DOX-induced oxidative damage and increased the levels of antioxidants in cardiac tissues. AF treatment inhibited the activation of nuclear factor-κB (NF-κB) and decreased the immuno-expression of NF-κB in cardiac tissue. Furthermore, AF caused a marked lowering in the level of inflammatory cytokines (nitric oxide, tumor necrosis factor-α, and interleukin-6) in the cardiac tissue. Collectively, this study demonstrates the cardioprotective activity of AF against DOX-induced cardiac damage which may be due to its antioxidant and anti-inflammatory activities.

Pristimerin protects against doxorubicin-induced cardiotoxicity and fibrosis through modulation of Nrf2 and MAPK/NF-kB signaling pathways.

BACKGROUND/PURPOSE: Pristimerin (Pris) is triterpenoid compound with many biological effects. Until now, nothing is known about its effect on doxorubicin (DOX)-induced cardiotoxicity. Hence, this study investigated the impact of Pris on DOX-induced cardiotoxic effects. MATERIALS AND METHODS: Rats were treated with Pris 1 week before and 2 weeks contaminant with repeated DOX injection. Afterwards, electrocardiography (ECG), biochemical, histopathological, PCR, and Western blot assessments were performed. RESULTS: Pris effectively alleviated DOX-induced deleterious cardiac damage. It inhibited DOX-induced ECG abnormities as well as DOX-induced elevation of serum indices of cardiotoxicity. The histopathological cardiac lesions and fibrosis were remarkably improved in Pris-treated animals. Pris reduced hydroxyproline content and attenuated the mRNA and protein expression of the pro-fibrogenic genes. The antioxidant activity of Pris was prominent through the amelioration of oxidative stress parameters and enhancement of antioxidants. Furthermore, Pris enhanced the activation of nuclear factor-erythroid 2 related factor 2 (Nrf2) signaling pathway as it increased the mRNA and protein expression of Nrf2 and Nrf2-dependent antioxidant genes (GCL, NQO1, HO-1). Additionally, the anti-inflammatory effect of Pris was obvious through the inhibition of mitogen activated protein kinase (MAPK)/nuclear factor kappa-B (NF-kB) signaling and subsequent inhibition of inflammatory mediators. CONCLUSION: This study provides evidence of the cardioprotective activity of Pris which is related to the modulation of Nrf2 and MAPK/NF-kB signaling pathways.

Agmatine protects against sodium valproate-induced hepatic injury in mice via modulation of nuclear factor-κB/inducible nitric oxide synthetase pathway.

Valproate is a widely used drug against epilepsy and several other neurological disorders although it has deleterious hepatotoxic side effects. The current study was designed to test if agmatine as nitric oxide modulator has protective effects against valproate-induced hepatic injury. Male Swiss albino mice were treated with sodium valproate (SVP) with or without agmatine for 7 days. Serum and liver samples were collected for analysis. Results have revealed that agmatine exerted hepatoprotective effects against SVP-associated hepatic injury. Agmatine ameliorated SVP-induced elevated serum biochemical markers of hepatic damage such as serum transaminases, alkaline phosphatase, γ-glutamyl transferase, and lactate dehydrogenase. Histopathological examination of the liver showed improvement of hepatic lesions in case of agmatine treatment. Furthermore, agmatine attenuated oxidative stress and enhanced antioxidants in liver tissue. Agmatine inhibited the activation of nuclear factor-κB and ameliorated the immunoexpression of inducible nitric oxide synthetase. This was accompanied by decrease in the level of inflammatory markers as nitrite/nitrate, tumor necrosis factor-α, and interleukin-6. These data provide new evidence of the hepatoprotective activity of agmatine against SVP-induced hepatotoxic effects.