Alleviation of microcystin-leucine arginine -induced hepatotoxicity: An updated overview.

OBJECTIVES: Contamination of surface waters is a major health threat for all living creatures. Some types of blue-green algae that naturally occur in fresh water, are able to produce various toxins, like Microcystins (MCs). Microcystin-leucine arginine (MC-LR) produced by Microcystis aeruginosa is the most toxic and abundant isoforms of MCs, and it causes hepatotoxicity. The present article reviews preclinical experiments examined different treatments, including herbal derivatives, dietary supplements and drugs against MC-LR hepatotoxicity. METHODS: We searched scientific databases Web of Science, Embase, Medline (PubMed), Scopus, and Google Scholar using relevant keywords to find suitable studies until November 2023. RESULTS: MC-LR through Organic anion transporting polypeptide superfamily transporters (OATPs) penetrates and accumulates in hepatocytes, and it inhibits protein phosphatases (PP1 and PP2A). Consequently, MC-LR disturbs many signaling pathways and induces oxidative stress thus damages cellular macromolecules. Some protective agents, especially plants rich in flavonoids, and natural supplements, as well as chemoprotectants were shown to diminish MC-LR hepatotoxicity. CONCLUSION: The reviewed agents through blocking the OATP transporters (nontoxic nostocyclopeptide-M1, captopril, and naringin), then inhibition of MC-LR uptake (naringin, rifampin, cyclosporin-A, silymarin and captopril), and finally at restoration of PPAse activity (silybin, quercetin, morin, naringin, rifampin, captopril, azo dyes) exert hepatoprotective effect against MC-LR.

The prescribing of cardioprotective medications and the impact on survival for patients with peripheral artery disease that undergo intervention.

BACKGROUND: Cardiovascular disease guidelines recommend that patients with established peripheral artery disease (PAD) are prescribed antihypertensive, lipid-lowering, and antiplatelet medication to reduce cardiovascular ischaemic events. However, the prescribing of these medications for patients with PAD within New Zealand (NZ) remains undefined. METHODS: This was a retrospective observational cohort study of patients in the Midland region of NZ, that underwent PAD-related percutaneous and surgical intervention between 1st January 2010 and 31st December 2021. Patient level data was collected. The primary outcome was prescribing of cardioprotective medications either before or within 1 year of incident procedure. Secondary outcome was overall survival. RESULTS: There were 2547 patients included. Antihypertensive prescription occurred in 80.7%, lipid-lowering in 77.4% and antithrombotic in 89.9%. Concomitant ischaemic heart disease increased prescription of cardioprotective medications. Women were prescribed less lipid-lowering medication compared to men. Maori men were prescribed less antiplatelet medication compared to non-Maori men. On univariate analysis lipid-lowering and antiplatelet medication showed survival advantage, while antihypertensive and anticoagulation did not. After adjustment for age, sex, end stage renal failure and presence of chronic limb-threatening ischaemia, best medical therapy was associated with better survival (HR 0.88, 95% CI 0.79-0.98, P = 0.02). CONCLUSION: This study highlights areas of deficiency in prescribing of cardioprotective medication in this high-risk group. These could be targets for national quality improvement initiatives.

Cisplatin-induced ototoxicity: a novel approach to an ancient problem.

With the scarcity of pharmacological otoprotective agents against cisplatin-induced ototoxicity (CIO), researchers find themselves compelled to look at and navigate all possible strategies to identify ways to prevent CIO. One of these promising strategies is pharmacogenomic implementation. This strategy aims for identifying and detecting high-risk genetic variants to tailor cisplatin therapy to reach the best survival outcomes with the least risk of ototoxicity.

Is the combination of linagliptin and allopurinol better prophylaxis against post-contrast acute kidney injury? A multicenter prospective randomized controlled study.

BACKGROUND: Patients with diabetic kidney disease (DKD) are at increased risk to develop post-contrast acute kidney injury (AKI). Diabetic patients under dipeptidyl peptidase 4 inhibitors (DPP4Is) experience a lower propensity to develop AKI. We speculated that linagliptin as a single agent or in combination with allopurinol may reduce the incidence of post-contrast AKI in stage 3-5 chronic kidney disease (CKD) patients with underlying DKD. METHODS: Out of 951 DKD patients eligible for this study, 800 accepted to sign informed consent. They were randomly allocated to 4 equal groups that received their prophylaxis for 2 days before and after radiocontrast. The first control group received N-acetyl cysteine and saline, the 2nd received allopurinol, the 3rd group received linagliptin, and the 4th received both allopurinol and linagliptin. Post-procedure follow-up for kidney functions was conducted for 2 weeks in all patients. RESULTS: 20, 19, 14, and 8 patients developed post-contrast AKI in groups 1 through 4, respectively. Neither linagliptin nor allopurinol was superior to N-acetyl cysteine and saline alone. However, the combination of the two agents provided statistically significant renal protection: post-contrast AKI in group 4 was significantly lower than in groups 1 and 2 (p < 0.02 and <0.03, respectively). None of the post-contrast AKI cases required dialysis. CONCLUSION: Linagliptin and allopurinol in combination may offer protection against post-contrast AKI in DKD exposed to radiocontrast. Further studies are needed to support this view. TRIAL REGISTRATION CLINICALTRIALS.GOV: NCT03470454.

Scutellaria baicalensis and its constituents baicalin and baicalein as antidotes or protective agents against chemical toxicities: a comprehensive review.

Scutellaria baicalensis (SB), also known as the Chinese skullcap, has a long history of being used in Chinese medicine to treat a variety of conditions ranging from microbial infections to metabolic syndrome and malignancies. Numerous studies have reported that treatment with total SB extract or two main flavonoids found in its root and leaves, baicalin (BA) and baicalein (BE), can prevent or alleviate the detrimental toxic effects of exposure to various chemical compounds. It has been shown that BA and BE are generally behind the protective effects of SB against toxicants. This paper aimed to review the protective and therapeutic effects of SB and its main components BA and BE against chemical compounds that can cause intoxication after acute or chronic exposure and seriously affect different vital organs including the brain, heart, liver, and kidneys. In this review paper, we had a look into a total of 221 in vitro and in vivo studies from 1995 to 2021 from the scientific databases PubMed, Scopus, and Web of Science which reported protective or therapeutic effects of BA, BE, or SB against drugs and chemicals that one might be exposed to on a professional or accidental basis and compounds that are primarily used to simulate disease models. In conclusion, the protective effects of SB and its flavonoids can be mainly attributed to increase in antioxidants enzymes, inhibition of lipid peroxidation, reduction of inflammatory cytokines, and suppression of apoptosis pathway.

Role of silymarin as antioxidant in clinical management of chronic liver diseases: a narrative review.

Chronic liver disease (CLD), manifested as hepatic injury, is a major cause of global morbidity and mortality. CLD progresses to fibrosis, cirrhosis, and-ultimately-hepatocellular carcinoma (HCC) if left untreated. The different phenotypes of CLD based on their respective clinical features and causative agents include alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), metabolic-associated fatty liver disease (MAFLD), and drug-induced liver injury (DILI). The preferred treatment modality for CLD includes lifestyle modification and diet, along with limited pharmacological agents for symptomatic treatment. Moreover, oxidative stress (OS) is an important pathological mechanism underlying all CLD phenotypes; hence, the use of antioxidants to manage the disease is justified. Based on available clinical evidence, silymarin can be utilized as a hepatoprotective agent, given its potent antioxidant, antifibrotic, and anti-inflammatory properties. The role of silymarin in suppressing OS has been well established, and therefore silymarin is recommended for use in ALD and NAFLD in the guidelines approved by the Russian Medical Scientific Society of Therapists and the Gastroenterology Scientific Society of Russia. However, to discuss the positioning of the original silymarin in clinical guidelines and treatment protocols as a hepatoprotective agent for managing CLD concomitantly with other therapies, an expert panel of international and Russian medical professionals was convened on 11 November 2020. The panel reviewed approaches for the prevention and treatment of OS, existing guidelines for patient management for CLD, and available evidence on the effectiveness of silymarin in reducing OS, fibrosis, and hepatic inflammation and presented in the form of a narrative review. Key messagesAn expert panel of international and Russian medical professionals reviewed existing guidelines for ALD, NAFLD, MAFLD, and DILI to establish consensus recommendations that oxidative stress is the common pathophysiological mechanism underlying these conditions.The panel also discussed the positioning of original silymarin in clinical guidelines and treatment protocols as a hepatoprotective agent for managing CLD concomitantly with other therapies.The panel reviewed the effectiveness of 140 mg original silymarin three times a day in reducing oxidative stress in chronic liver diseases such as ALD, NAFLD, MAFLD, and DILI.

Schisandra chinensis Oil Attenuates Aristolochic Acid I-Induced Nephrotoxicity in vivo and in vitro.

OBJECTIVE: To investigate the protective effects of Schisandra chinensis oil (SCEO) against aristolochic acid I (AA I)-induced nephrotoxicity in vivo and in vitro and elucidate the underlying mechanism. METHODS: C57BL/6 mice were randomly divided into 5 groups according to a random number table, including control group, AA I group, and AA I +SCEO (0.25, 0.5 and 1 g/kg) groups (n=5 per group). Pretreatment with SCEO was done for 2 days by oral administration, while the control and AA I groups were treated with sodium carboxymethyl cellulose. Mice of all groups except for the control group were injected intraperitoneally with AA I (5 mg/kg) from day 3 until day 7. Histopathological examination and apoptosis of kidney tissue were observed by hematoxylin and eosin and TdT-mediated dUTP nick-end labeling (TUNEL) staining, respectively. The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), and serum creatinine (SCr), as well as renal malondialdehyde (MDA), glutathione, r-glutamyl cysteingl+glycine (GSH), and superoxide dismutase (SOD) were analyzed using enzyme-linked immunosorbent assay (ELISA). Expressions of hepatic cytochrome P450 1A1 (CYP1A1), CYP1A2, and nad(p)hquinonedehydrogenase1 (NQO1) were analyzed using ELISA, quantitative real-time polymerase chain reaction (qPCR) and Western blot, respectively. In vitro, SCEO (40 µ g/mL) was added 12 h before treatment with AA I (40 µ mol/mL for 48 h) in human renal proximal tubule cell line (HK-2), then apoptosis and reactive oxygen species (ROS) were analyzed by flow cytometry. RESULTS: SCEO 0.5 and 1 g/kg ameliorated histopathological changes and TUNEL+ staining in the kidney tissues of mice with AA I-induced nephrotoxicity, and reduced serum levels of ALT, AST, BUN and SCr (P<0.01 or P<0.05). SCEO 0.5 and 1 g/kg alleviated the ROS generation in kidney, containing MDA, GSH and SOD (P<0.01 or P<0.05). SCEO 1 g/kg increased the expressions of CYP1A1 and CYP1A2 and decreased NQO1 level in the liver tissues (P<0.01 or P<0.05). Besides, in vitro studies also demonstrated that SCEO 40 µ g/mL inhibited apoptosis and ROS generation (P<0.05 or P<0.01). CONCLUSIONS: SCEO can alleviate AA I-induced kidney damage both in vivo and in vitro. The protective mechanism may be closely related to the regulation of metabolic enzymes, thereby inhibiting apoptosis and ROS production.

Trimetazidine, a metabolic modulator, attenuates silica-induced pulmonary fibrosis and decreases lactate levels and LDH activity in rats.

Pulmonary fibrosis has been recently linked to metabolic dysregulation. Silica-induced pulmonary fibrosis in rats was employed by the current study to explore the effects of trimetazidine (a metabolic modulator-antianginal drug; TMZ) on silica-induced pulmonary fibrosis. Pulmonary fibrosis was induced by intranasal instillation of silica (50 mg/100 µl/rat) in TMZ versus vehicle-treated rats. Body weights of rats, weights of lungs, and wet-to-dry lung weights were determined. Various parameters were also measured in serum, bronchoalveolar lavage fluid (BALF) in addition to lung tissue homogenates. Moreover, histopathological examination of sectioned lungs for lesion score and distribution and histochemical detection of myeloperoxidase (MPO) in lung tissues were also performed. No significant differences were observed in body weight gains, lung coefficients, lung weights, and wet-to-dry lung weight in silica versus control rats. Elevated lactate levels in serum and lung homogenates were significantly attenuated by TMZ. In addition, lactate dehydrogenase activity, transforming growth factor-ß, and total proteins in BALF were significantly normalized with TMZ. Moreover, TMZ significantly increased reduced glutathione and adenosine triphosphate levels and decreased nitrate/nitrite and hydroxyproline content in lungs of silica-treated rats. Histopathological examination of lungs revealed more than 56% reduction in lesion score and distribution by TMZ. MPO expression in lungs of silica-treated rats was also significantly attenuated by TMZ. TMZ attenuates silica-induced pulmonary fibrosis, an effect that could be mediated by suppressing anaerobic glycolysis-induced excessive lactate production. Regulation of oxidative stress could also play a role in TMZ-promoted protective effects.

Lyophyllum decastes fruiting body polysaccharide alleviates acute liver injury by activating the Nrf2 signaling pathway.

Polysaccharides have high antioxidant, hypoglycemic, hypolipidemic, hepatoprotective, anti-tumor, and anticancer activities. In this study, the ability of the Lyophyllum decastes fruiting body polysaccharide (LDFP) to protect against CCl4-induced acute liver injury in mice by activating the Nrf2 pathway was studied. LDFP can inhibit the activity of ALT, AST, TC, TG, tumor necrosis factor (TNF-α), and interleukin-6 (IL-6) in serum; significantly improve the inflammatory state of the liver; increase the activity of superoxide dismutase (SOD) and the glutathione (GSH) content; decrease the malondialdehyde (MDA) content; alleviate the toxicity caused by reactive oxygen species; and alleviate liver injury. Immunohistochemistry and western blot showed that LDFP can activate the Nrf2 pathway, up-regulate the expression of Nrf2, down-regulate the expression of Keap1, and increase the expression of the anti-oxidation factors HO-1 and CuZn-SOD. At the same time, it was found that the expression of the transcription factors TLR-4 and NF-κB were decreased in the NF-κB signaling pathway, the synthesis and secretion of the pro-inflammatory factors IL-6 and TNF-α were decreased consequently. These results suggest that LDFP protects the liver by activating the Nrf2 pathway and reducing the inflammatory response. Generally, the results of this study could be used to aid the development of hepatoprotective products and their application.

Hepatoprotective effects of sea cucumber ether-phospholipids against alcohol-induced lipid metabolic dysregulation and oxidative stress in mice.

Sea cucumber is widely consumed as food and folk medicine in Asia, and its phospholipids are rich sources of dietary eicosapentaenoic acid enriched ether-phospholipids (ether-PLs). Emerging evidence suggests that ether-PLs are associated with neurodegenerative disease and steatohepatitis. However, the function and mechanism of ether-PLs in alcoholic liver disease (ALD) are not well understood. To this end, the present study sought to investigate the hepatoprotective effects of sea cucumber ether-PLs, including plasmenyl phosphatidylethanolamine (PlsEtn) and plasmanyl phosphatidylcholine (PlsCho), and their underlying mechanisms. Our results showed that compared with EtOH-induced mice, ether-PL treated mice showed improved liver histology, decreased serum ALT and AST levels, and reduced alcohol metabolic enzyme (ALDH2 and ADH1) expressions. Mechanistic studies showed that ether-PLs attenuated "first-hit" hepatic steatosis and lipid accumulation evoked by alcohol administration. Moreover, PlsEtn more effectively restored endogenous plasmalogen levels than PlsCho, thereby enhancing hepatic antioxidation against "second-hit" reactive oxygen species (ROS) due to the damaged mitochondria and abnormal ethanol metabolism. Taken together, sea cucumber ether-PLs show great potential to become a natural functional food against chronic alcohol-induced hepatic steatosis and lipid metabolic dysregulation.

Icariin attenuates thioacetamide­induced bone loss via the RANKL­p38/ERK­NFAT signaling pathway.

There is an increasing incidence of destructive bone disease caused by osteoclast proliferation. This is characterized by reduced bone mass and imbalance of bone homeostasis. Icariin (ICA), a flavonoid compound isolated from Epimedium, has anti­osteoporosis activity and inhibits the formation of osteoclasts and bone resorption. The purpose of the present study was to investigate the protective effect of ICA on osteoclastic differentiation induced by thioacetamide (TAA) and its possible mechanism in Sprague Dawley (SD) rats. In the present study, SD rats were intraperitoneally injected with TAA (300 mg/kg) for the bone loss model, treated with ICA (600 mg/kg, intragastric gavage) in the ICA group and TAA+ICA group for treatment of bone loss for 6 weeks. Indexes associated with bone metabolism, such as alkaline phosphatase, N­terminal telopeptide of type­I collagen (NTX­I), calcium (Ca), phosphorus (P) and magnesium (Mg) in the serum, were detected. Osteoclast differentiation of femoral tissues was detected by hematoxylin and eosin and tartrate­resistant acid phosphatase staining. The femoral bone mass was evaluated using a three­point bending test and micro computed tomography. Western blotting was used to detect the expression levels of osteoclast­related proteins in each group. In the rats treated with TAA, the serum concentrations of Ca, P and Mg were decreased, the serum concentration of NTX­I was increased, osteoclast differentiation of the femur was increased, femur bone stress and bone mass were decreased and the bone loss and osteoclast formation were reduced after ICA treatment. In addition, ICA inhibited the protein expression of receptor activator of nuclear factor κ­Β ligand (RANKL), receptor activator of nuclear factor κ­B (RANK), p38, ERK, c­Fos and nuclear factor of activated T cells 1 (NFATc1) in the femur of rats treated with TAA. The results suggested that ICA may inhibit osteoclast differentiation by downregulating the RANKL­p38/ERK­NFAT signaling pathway and prevent TAA­induced bone loss. The results are helpful to understand the mechanism of osteoclast differentiation induced by TAA, as well as the antiresorptive activity and molecular mechanism of ICA, and to provide new ideas for the treatment of osteolytic diseases.

Antioxidant Extract from Cleistocalyx nervosum var. paniala Pulp Ameliorates Acetaminophen-Induced Acute Hepatotoxicity in Rats.

The indigenous purplish red fruit, Cleistocalyx nervosum var. paniala (CN), is grown in northern Thailand. The aqueous extract of CN pulp is known to exhibit antioxidant and anticarcinogenic properties. To search for an antioxidant fraction separated from CN, various hydroalcoholic extractions were performed. The acidified ethanolic extract of CN obtained from 0.5% (v/v) citric acid in 80% (v/v) ethanol yielded greater polyphenol content and DPPH radical scavenging activity when compared with other hydroethanolic extracts. Cyanidin-3-glucoside is a major anthocyanin present in the acidified ethanolic extract of CN (AECN). At a dose of 5000 mg/kg bw, an anthocyanin-rich extract was found to be safe when given to rats without any acute toxicity. To examine the hepatoprotective properties of AECN, an overdose of acetaminophen (APAP) was induced in a rat model, while silymarin was used as a standard reference. The administration of AECN at a dose of 300 mg/kg bw for 28 days improved hepatocyte architecture and modulated serum alanine aminotransferase levels in APAP-induced rats. Furthermore, it significantly decreased serum and hepatic malondialdehyde levels but increased hepatic glutathione content, as well as glutathione peroxidase and UDP-glucuronosyltransferase activities. In conclusion, AECN may effectively reduce oxidative stress induced acute hepatotoxicity in overdose APAP-treated rats through the suppression of oxidative stress and the enhancement of the antioxidant system in rat livers.

d-allulose protects against diabetic nephropathy progression in Otsuka Long-Evans Tokushima Fatty rats with type 2 diabetes.

d-allulose is a rare sugar that has been reported to possess anti-hyperglycemic effects. In the present study, we hypothesized that d-allulose is effective in attenuating the progression of diabetic nephropathy in the Otsuka Long-Evans Tokushima Fatty (OLETF) rat model of type 2 diabetes mellitus. Drinking water with or without 3% d-allulose was administered to OLETF rats for 13 weeks. Long-Evans Tokushima Otsuka rats that received drinking water without d-allulose were used as non-diabetic control rats. d-allulose significantly attenuated the increase in blood glucose levels and progressive mesangial expansion in the glomerulus, which is regarded as a characteristic of diabetic nephropathy, in OLETF rats. d-allulose also attenuated the significant increases in renal IL-6 and tumor necrosis factor-α mRNA levels in OLETF rats, which is a proinflammatory parameter. Additionally, we showed that d-allulose suppresses mesangial matrix expansion, but its correlation with suppressing renal inflammation in OLETF rats should be investigated further. Collectively, our results support the hypothesis that d-allulose can prevent diabetic nephropathy in rats.

Intraarterial anti-leptin therapy via ICA protects ipsilateral CA1 neurons subjected to ischemia and reperfusion.

BACKGROUND: Brain reperfusion following an ischemic event is essential for tissue viability, however, it also involves processes that promote neuronal cell death. We have recently shown that local expression of the hormone leptin in cardiovascular organs drives deleterious remodeling. As cerebral ischemia-reperfusion (IR) lesions derive expression of both the leptin hormone and its receptor, we hypothesized that blocking leptin activity in the injured brain area will reduce the deleterious effects of IR injury. METHODS: C57BL6 male mice underwent bilateral common carotid artery and external carotid artery ligation. The right hemisphere was reperfused after 12 minutes, followed by intraarterial injection of either a low-dose leptin antagonist or saline solution via the ipsilateral ICA. The left common carotid artery remained ligated. Fifteen IR/leptin antagonist-injected and fourteen IR/saline-injected mice completed the experiment. Five days after surgery brains were collected and samples of the hippocampal CA1 region were analyzed for cell viability (H&E) and apoptosis (TUNEL and caspase3), for neuroinflammation (Iba1), and for signaling pathways of pSTAT3 and pSmad2. RESULTS: The right hemisphere hippocampal CA1 region subjected to IR and saline injection exhibited increased apoptosis and necrosis of pyramidal cells. Also, increased density of activated microglia/macrophages was evident around the CA1 region. Comparatively, leptin antagonist treatment at reperfusion reduced apoptosis and necrosis of pyramidal cells, as indicated by increased number of viable cells (p < 0.01), and reduced TUNEL (p < 0.001) and caspase3-positive cells (p<0.05). Furthermore, this treatment reduced the density of activated microglia/macrophages (p < 0.001) in the CA1 region. Signaling pathway analysis revealed that while pSTAT3 and pSmad2-positive cells were found surrounding the stratum pyramidal in saline-treated animals, pSTAT3 signal was undetected and pSmad2 was greatly reduced in this territory following leptin antagonist treatment (p < 0.01). CONCLUSIONS: Inhibition of leptin activity in hemispheric IR injury preserved the viability of ipsilateral hippocampal CA1 neurons, likely by preventing apoptosis and local inflammation. These results indicate that intraarterial anti-leptin therapy may have clinical potential in reducing hemispheric brain IR injury.

Pyrvinium pamoate ameliorates cyclosporin A- induced hepatotoxicity via the modulation of Wnt/ß-catenin signaling and upregulation of PPAR-γ.

BACKGROUND: Cyclosporin A (CsA) is an immunosuppressive agent that can be used to treat autoimmune diseases. Despite its hepatotoxicity, CsA is a backbone in organ transplantation. Pyrvinium pamoate (PP) is an inhibitor of Wnt signaling approved by the U.S. Food and Drug Administration for its anthelmintic properties. AIM: The goal of this investigation was to determine whether PP could protect against CsA-induced hepatotoxicity. METHOD: Five groups of 50 albino male mice were selected and divided into five groups; group 1 was the control, groups 2 to 4 were subjected to daily CsA (25 mg/kg, i.p), in which groups 3 and 4 were treated with graded dose of PP (0.25, 0.5 mg/kg), and group 5 was treated with PP (0.5 mg/ kg) for 21 days. The mice were sacrificed under anesthesia, and their livers were removed for histological and biochemical assessment. RESULTS: CsA was found to cause a striking increase in liver enzymes, total bilirubin, and malondialdehyde levels while significantly decreasing the levels of albumin, glutathione, and antioxidant enzymes in the treated groups. The tissue levels of tumor necrosis factor-α, interleukin-1ß, and NFКB were also significantly higher with CsA treatment. Moreover, CsA triggered a notable increase in the levels of apoptotic marker P53. CsA activated the Wnt/ß-catenin pathway by increasing WNT3a expression, frizzled receptor-7, ß-catenin, and c-myc. On the other hand, the levels of PPAR-γ decreased significantly with CsA. CsA-induced alterations in the previously stated parameters were greatly reduced by PP, indicating its antioxidant, anti-inflammatory, and antiapoptotic properties. CONCLUSIONS: PP may be considered as a promising agent to prevent CsA hepatotoxicity.

ß-glucan-coupled superparamagnetic iron oxide nanoparticles induce trained immunity to protect mice against sepsis.

Background: Innate immune memory, also termed "trained immunity", is thought to protect against experimental models of infection, including sepsis. Trained immunity via reprogramming monocytes/macrophages has been reported to result in enhanced inflammatory status and antimicrobial activity against infection in sepsis. However, a safe and efficient way to induce trained immunity remains unclear. Methods: ß-glucan is a prototypical agonist for inducing trained immunity. Ferumoxytol, superparamagnetic iron oxide (SPIO) with low cytotoxicity, has been approved by FDA for clinical use. We synthesized novel nanoparticles BSNPs by coupling ß-glucan with SPIO. BSNPs were further conjugated with fluorescein for quantitative analysis and trace detection of ß-glucan on BSNPs. Inflammatory cytokine levels were measured by ELISA and qRT-PCR, and the phagocytosis of macrophages was detected by flow cytometry and confocal microscopy. The therapeutic effect of BSNPs was evaluated on the well-established sepsis mouse model induced by both clinical Escherichia coli (E. coli) and cecal ligation and puncture (CLP). Results: BSNPs were synthesized successfully with a 3:20 mass ratio of ß-glucan and SPIO on BSNPs, which were mainly internalized by macrophages and accumulated in the lungs and livers of mice. BSNPs effectively reprogrammed macrophages to enhance the production of trained immunity markers and phagocytosis toward bacteria. BSNP-induced trained immunity protected mice against sepsis caused by E. coli and CLP and also against secondary infection. We found that BSNP treatment elevated Akt, S6, and 4EBP phosphorylation, while mTOR inhibitors decreased the trained immunity markers and phagocytosis enhanced by BSNPs. Furthermore, the PCR Array analysis revealed Igf1, Sesn1, Vegfa, and Rps6ka5 as possible key regulators of mTOR signaling during trained immunity. BSNP-induced trained immunity mainly regulated cellular signal transduction, protein modification, and cell cycle by modulating ATP binding and the kinase activity. Our results indicated that BSNPs induced trained immunity in an mTOR-dependent manner. Conclusion: Our data highlight that the trained immunity of macrophages is an effective strategy against sepsis and suggest that BSNPs are a powerful tool for inducing trained immunity to prevent and treat sepsis and secondary infections.

Emodin Attenuates Acetaminophen-Induced Hepatotoxicity via the cGAS-STING Pathway.

Emodin is a natural bioactive compound from traditional Chinese herbs that exerts anti-inflammatory, antioxidant, anticancer, hepatoprotective, and neuroprotective effects. However, the protective effects of emodin in acetaminophen (APAP)-induced hepatotoxicity are not clear. The present study examined the effects of emodin on APAP-induced hepatotoxicity and investigated the potential molecular mechanisms. C57BL/6 mice were pretreated with emodin (15 and 30 mg/kg) for 5 consecutive days and then given APAP (300 mg/kg) to establish an APAP-induced liver injury model. Mice were sacrificed to detect the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and albumin (ALB) and the liver tissue levels of glutathione (GSH), malondialdehyde (MDA), and superoxide dismutase (SOD). Histological assessment, Western blotting, and ELISA were performed. Emodin pretreatment significantly reduced the levels of ALT, AST, and ALP; increased the levels of ALB; alleviated hepatocellular damage and apoptosis; attenuated the exhaustion of GSH and SOD and the accumulation of MDA; and increased the expression of antioxidative enzymes, including nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), and NAD(P)H quinone dehydrogenase 1 (NQO1). Emodin also inhibited the expression of NLRP3 and reduced the levels of pro-inflammatory factors, including interleukin-1 beta (IL-1ß), IL-6, and tumor necrosis factor-alpha (TNF-α). Emodin inhibited interferon (IFN)-α, cyclic GMP-AMP synthase (cGAS), and its downstream signaling effector stimulator of interferon genes (STING) expression to protect the liver against APAP-induced inflammatory responses and apoptosis. These results suggest that emodin protected hepatocytes from APAP-induced liver injury via the upregulation of the Nrf2-mediated antioxidative stress pathway, the inhibition of the NLRP3 inflammasome, and the downregulation of the cGAS-STING signaling pathway.

Salubrinal protects against inflammatory response in macrophage and attenuates psoriasiform skin inflammation by antagonizing NF-κB signaling pathway.

Psoriasiform skin inflammation is the common chronic skin inflammatory disease with no effective clinical therapy. Salubrinal is a multifunctional molecule playing a protective role in several conditions. Recently, studies have reported that Salubrinal is a potential therapeutic agent for inflammatory diseases. However, the protective role of Salubrinal in psoriasis-like skin inflammation remains unknown. In this article, imiquimod (IMQ)-induced psoriasis models were established in wild-type mice to explore the role of Salubrinal in the development of psoriasis. As a result, the IMQ-induced mouse models exhibited typical skin inflammation, which was alleviated by the administration of Salubrinal. Furthermore, RAW264.7 macrophage was stimulated with Lipopolysaccharide(LPS) in the presence or absence of Salubrinal. LPS stimulation elevated the expression of various inflammatory biomarkers, while the administration of Salubrinal abolished the function of LPS in RAW264.7 macrophages. In addition, the activation of the nuclear factor-kappa B (NF-κB) signaling pathway in both the LPS-stimulated RAW264.7 macrophage and psoriasis mouse models was antagonized by the administration of Salubrinal. Collectively, Salubrinal might be considered as a promising therapeutic agent for psoriasis-like skin inflammation.

Hepatoprotective effects of gemigliptin and empagliflozin in a murine model of diet-induced non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) includes a broad spectrum of liver diseases characterized by steatosis, inflammation, and fibrosis. This study aimed to investigate the potential of dipeptidyl peptidase-4 inhibitors and sodium-glucose cotransporter 2 inhibitors in alleviating the progression of NAFLD. The NAFLD model was generated by feeding male C57BL/6J mice a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) for 7 weeks. After 2 weeks of CDAHFD feeding, the NAFLD model mice were assigned to four groups, namely (ⅰ) VEHICLE, (ⅱ) gemigliptin (GEMI), (ⅲ) empagliflozin (EMPA), and (ⅳ) GEMI + EMPA. For the next 5 weeks, mice received the vehicle or the drug based upon the group to which they belonged. Thereafter, the triglyceride concentration, extent of fibrosis, and the expression of genes encoding inflammatory cytokines, chemokines, and antioxidant enzymes were analyzed in the livers of mice. The NAFLD activity score and hepatic fibrosis grade were assessed via hematoxylin and eosin and Sirius Red staining of the liver tissue samples. All mice belonging to the GEMI, EMPA, and GEMI + EMPA groups showed improvements in the accumulation of liver triglycerides and the expression of inflammatory cytokines and chemokines. Additionally, the oxidative stress was reduced due to inhibition of the c-Jun N-terminal kinase pathway and upregulation of the antioxidant enzymes. Furthermore, in these three groups, the galectin-3 and interleukin 33-induced activity of tumor necrosis factor-α was inhibited, thereby preventing the progression of liver fibrosis. These findings suggest that the GEMI, EMPA, and GEMI + EMPA treatments ameliorate hepatic steatosis, inflammation, oxidative stress, and fibrosis in CDAHFD-induced NAFLD mouse models.

Emodin prevents renal ischemia-reperfusion injury via suppression of CAMKII/DRP1-mediated mitochondrial fission.

Acute kidney injury (AKI) is a serious threat to human health. Clinically, ischemia-reperfusion (I/R) injury is considered one of the most common contributors to AKI. Emodin has been reported to alleviate I/R injury in the heart, brain, and small intestine in rats and mice through its anti-inflammatory effects. The present study investigated whether emodin improved AKI induced by I/R and elucidated the molecular mechanisms. We used a mouse model of renal I/R injury and human renal tubular epithelial cell model of hypoxia/reoxygenation (H/R) injury. Ischemia/reperfusion resulted in renal dysfunction. Pretreatment with emodin ameliorated renal injury in mice following I/R injury. Emodin reduced mitochondrial-mediated apoptosis, suppressed the overproduction of mitochondrial reactive oxygen species and accelerated the recovery of adenosine triphosphate both in vivo and in vitro. Emodin prevented mitochondrial fission and restored the balance of mitochondrial dynamics. The phosphorylation of dynamin-related protein 1 (DRP1) at Ser616, a master regulator of mitochondrial fission, was upregulated in both models of I/R and H/R injury, and this upregulation was blocked by emodin. Using computational cognate protein kinase prediction and specific kinase inhibitors, we found that emodin inhibited the phosphorylation of calcium/calmodulin-dependent protein kinase II (https://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=1554), thereby inhibiting its kinase activity and reducing the phosphorylation of DRP1 at Ser616. The results demonstrated that emodin pretreatment could protect renal function by improving mitochondrial dysfunction induced by I/R.