Anti-inflammatory effects of triptolide by inhibiting the NF-κB signalling pathway in LPS-induced acute lung injury in a murine model

Triptolide activates the Nrf2 signaling pathway and inhibits the NF-κB signaling pathway to improve Alzheimer disease

Alzheimer disease (AD) is a common neurodegenerative disease with pathological features of accumulated amyloid plaques, neurofibrillary tangles, and the significant inflammatory environment. These features modify the living microenvironment for nerve cells, causing the damage, dysfunction, and death. Progressive neuronal loss directly leads to cognitive decline in AD patients and is closely related to brain inflammation. Therefore, impairing inflammation via signaling pathways may facilitate either the prevention or delay of the degenerative process. Triptolide has been evidenced to possess potent anti-inflammatory effect. In this review, we elaborate on two signaling pathways (the NF-κB and Nrf2 signaling pathways) that are involved in the anti-inflammatory effect of triptolide.

Jinzhen Oral Liquid alleviates lipopolysaccharide-induced acute lung injury through modulating TLR4/MyD88/NF-κB pathway

BACKGROUND

Acute lung injury (ALI) has the attribution of excessive inflammation of the lung. Jinzhen oral liquid (JO), a famous Chinese recipe used to treat ALI, has a favorable therapeutic effect on ALI. However, its anti-inflammatory mechanism has not been extensively studied.

PURPOSE

This study was to elucidate the effects of JO on lipopolysaccharide (LPS)-induced ALI and its molecular mechanism.

METHODS

An ALI model was established by intratracheal instillation of LPS (2 mg/50 μl). The open field experiment was carried out to explore the spontaneous movement and exploratory behavior of ALI mice. Cytokines levels concentrations (IL-6, IL-10 and TNF-α) were determined by enzyme-linked immunosorbent assay (ELISA). Network pharmacology was used to predict the mechanism of JO against ALI. Immunofluorescence, co-immunoprecipitation, fluorescence resonance energy transfer (FRET), Western blot and RT-PCR were used to verify the molecular mechanisms of JO.

RESULTS

The in vivo results suggested that JO (1, 2, 4 g/kg) dose-dependently improved the exercise performance of mice and reduced the lung W/D weight ratio as well as the production of IL-6 and TNF-α, but increased the release of IL-10 in the ALI group. The network pharmacological analysis demonstrated that the Toll-like receptor (TLR) pathway might be the fundamental action mechanisms of JO against ALI. Immunofluorescence staining and co-immunoprecipitation analysis showed that JO decreased the expression levels of TLR4 and MyD88 and reduced their interaction in the lung tissue of ALI mice. Meanwhile, JO decreased nuclear translocation and phosphorylation of NF-κB P65. The results from cellular experiments were in line with those in vivo. The FRET experiment also confirmed that JO disturbed the interaction of TLR4 and MyD88. Subsequently, we also found that the six indicative components of JO have the similar therapeutic effect as JO.

CONCLUSIONS

In summary, we suggested that JO suppressed the TLR4/MyD88/NF-κB signaling pathway, thus inhibiting LPS-induced ALI in vitro and in vivo. The clarified mechanism provided an important theoretical basis and a novel treatment strategy for the ALI treatment of JO.

Triptolide Attenuates Muscular Inflammation and Oxidative Stress in a Delayed-Onset Muscle Soreness Animal Model

Delayed-onset muscle soreness (DOMS) is associated with exercise-induced muscle damage and inflammation, which is mainly caused by prolonged eccentric exercise in humans. Triptolide, an extract from the Chinese herb Tripterygium wilfordii Hook F, has been used for treating autoimmune and inflammatory diseases in clinical practice. However, whether triptolide attenuates acute muscle damage is still unclear. Here, we examined the effect of triptolide on carrageenan-induced DOMS in rats. Rats were injected with 3% of carrageenan into their muscles to induce acute left gastrocnemius muscular damage, and triptolide treatment attenuated carrageenan-induced acute muscular damage without affecting hepatic function. Triptolide can significantly decrease lipid hydroperoxide and nitric oxide (NO) levels, proinflammatory cytokine production, and the activation of nuclear factor (NF)-ĸB, as well as increase a reduced form of glutathione levels in carrageenan-treated rat muscles. At the enzyme levels, triptolide reduced the inducible nitric oxide synthase (iNOS) expression and muscular myeloperoxidase (MPO) activity in carrageenan-treated DOMS rats. In conclusion, we show that triptolide can attenuate muscular damage by inhibiting muscular oxidative stress and inflammation in a carrageenan-induced rat DOMS model.

Triptolide Inhibits the Biological Processes of HUVECs and HepG2 Cells via the Serine Palmitoyltransferase Long Chain Base Subunit 2/Sphingosine-1-Phosphate Signaling Pathway

Triptolide (TP) has demonstrated innumerous biological effects and pharmacological potential against different cancer types. Hepatocellular carcinoma has a high incidence in men, and its incidence is increasing year by year. Studies have shown that angiogenesis plays an important role in the formation of tumors and that angiogenesis is closely related to tumor growth and metastasis. Deregulation of sphingolipids signaling has been associated with several pathological conditions, including cancer. In the present study, we aimed at exploring the potential molecular mechanism of TP's antivascular and antitumor effects in vitro from the perspective of sphinolipids. Human umbilical vein endothelial cells (HUVECs) and HepG2 cells were, respectively, treated with different concentrations of TP and transfected. Then, the effect of HUVECs on HepG2 cells was investigated using a three-dimensional coculture model system. CCK-8 assay was performed for cell proliferation. Cell migration and invasion abilities were assessed using the transwell assay. Cell adhesion and tube formation were detected by Matrigel. RT-PCR and western blotting were used to detect the mRNA and protein expression. The S1P production was measured via ELISA assay. Our results showed that TP inhibited HUVECs and HepG2 cells proliferation, migration, invasion, adhesion, angiogenesis, and serine palmitoyltransferase long chain base subunit 2 (SPTLC2) expression; upregulating SPTLC2 facilitated the proliferation, migration, invasion, adhesion, angiogenesis, and sphingosine-1-phosphate (S1P) production of HUVECs and HepG2 cells, while interfering with SPTLC2 expression inhibited them; HUVECs facilitated the proliferation, migration, invasion, S1P production, S1PR1, and S1PR2 expression of HepG2 cells, while S1PR3 expression was decreased. In conclusion, SPTLC2 may be associated with the antivascular and antitumor effects of TP, and SPTLC2 is expected to become a new marker for tumor therapy. HUVECs can promote the proliferation, migration, and invasion of HepG2 cells, which may be related to the S1P/sphingosine-1-phosphate receptor (S1PR) signaling pathway.

Triptolide increases resistance to bile duct ligation-induced liver injury and fibrosis in mice by inhibiting RELB

Cholestasis is a common, chronic liver disease that may cause fibrosis and cirrhosis. Tripterygium wilfordii Hook.f (TWHF) is a species in the Euonymus family that is commonly used as a source of medicine and food in Eastern and Southern China. Triptolide (TP) is an epoxy diterpene lactone of TWHF, as well as the main active ingredient in TWHF. Here, we used a mouse model of common bile duct ligation (BDL) cholestasis, along with cultured human intrahepatic biliary epithelial cells, to explore whether TP can relieve cholestasis. Compared with the control treatment, TP at a dose of 70 or 140 μg/kg reduced the serum levels of the liver enzymes alanine transaminase, aspartate aminotransferase, and alkaline phosphatase in mice; hematoxylin and eosin staining also showed that TP reduced necrosis in tissues. Both in vitro and in vivo analyses revealed that TP inhibited cholangiocyte proliferation by reducing the expression of RelB. Immunohistochemical staining of CK19 and Ki67, as well as measurement of Ck19 mRNA levels in hepatic tissue, revealed that TP inhibited the BDL-induced ductular reaction. Masson 3 and Sirius Red staining for hepatic hydroxyproline showed that TP alleviated BDL-induced hepatic fibrosis. Additionally, TP substantially inhibited BDL-induced hepatic inflammation. In summary, TP inhibited the BDL-induced ductular reaction by reducing the expression of RelB in cholangiocytes, thereby alleviating liver injury, fibrosis, and inflammation.

Glycyrrhizic Acid Alleviates Lipopolysaccharide (LPS)-Induced Acute Lung Injury by Regulating Angiotensin-Converting Enzyme-2 (ACE2) and Caveolin-1 Signaling Pathway

Acute lung injury (ALI) is mainly caused by severe infection, shock, trauma, and burn, which causes the extensive release of inflammatory factors and other mediators. As a major bioactive constituent of traditional Chinese herb licorice, glycyrrhizic acid (GA) plays an important effect on inflammatory regulation. Nevertheless, the exact mechanism of this effect remains unclear. The present study aims to explore the potential protective effect of GA on LPS-induced ALI. Our results showed that GA significantly attenuated LPS-induced ALI and decreased the production of inflammatory factors, including IL-1β, MCP-1, COX2, HMGB1, and adhesion molecules, such as E-selectin, VCAM-1, and modulated expression of angiotensin-converting enzyme 2 (ACE2). Moreover, treatment of ACE2 inhibitor (MLN-4760) reversed the effects of GA on the secretion of pro-inflammatory factors in ALI. Additionally, GA exerts its protective effect by regulating the ACE2 and caveolin-1/NF-κB signaling pathway. In conclusion, this study showed that GA alleviated LPS-induced ALI by upregulating ACE2 and inhibiting the caveolin-1/NF-κB signaling pathway.

Terpenoids' anti-cancer effects: focus on autophagy

Terpenoids are the largest class of natural products, most of which are derived from plants. Amongst their numerous biological properties, their anti-tumor effects are of interest for they are extremely diverse which include anti-proliferative, apoptotic, anti-angiogenic, and anti-metastatic activities. Recently, several in vitro and in vivo studies have been dedicated to understanding the 'terpenoid induced autophagy' phenomenon in cancer cells. Light has already been shed on the intricacy of apoptosis and autophagy relationship. This latter crosstalk is driven by the delicate balance between activating or silencing of certain proteins whereby the outcome is expressed via interrelated signaling pathways. In this review, we focus on nine of the most studied terpenoids and on their cell death and autophagic activity. These terpenoids are grouped in three classes: sesquiterpenoid (artemisinin, parthenolide), diterpenoids (oridonin, triptolide), and triterpenoids (alisol, betulinic acid, oleanolic acid, platycodin D, and ursolic acid). We have selected these nine terpenoids among others as they belong to the different major classes of terpenoids and our extensive search of the literature indicated that they were the most studied in terms of autophagy in cancer. These terpenoids alone demonstrate the complexity by which these secondary metabolites induce autophagy via complex signaling pathways such as MAPK/ERK/JNK, PI3K/AKT/mTOR, AMPK, NF-kB, and reactive oxygen species. Moreover, induction of autophagy can be either destructive or protective in tumor cells. Nevertheless, should this phenomenon be well understood, we ought to be able to exploit it to create novel therapies and design more effective regimens in the management and treatment of cancer.

EGCG promotes PRKCA expression to alleviate LPS-induced acute lung injury and inflammatory response

Acute lung injury (ALI), which could be induced by multiple factors such as lipopolysaccharide (LPS), refer to clinical symptoms of acute respiratory failure, commonly with high morbidity and mortality. Reportedly, active ingredients from green tea have anti-inflammatory and anticancer properties, including epigallocatechin-3-gallate (EGCG). In the present study, protein kinase C alpha (PRKCA) is involved in EGCG protection against LPS-induced inflammation and ALI. EGCG treatment attenuated LPS-stimulated ALI in mice as manifested as improved lung injury scores, decreased total cell amounts, neutrophil amounts and macrophage amounts, inhibited the activity of MPO, decreased wet-to-dry weight ratio of lung tissues, and inhibited release of inflammatory cytokines TNF-α, IL-1β, and IL-6. PRKCA mRNA and protein expression showed to be dramatically decreased by LPS treatment while reversed by EGCG treatment. Within LPS-stimulated ALI mice, PRKCA silencing further aggravated, while PRKCA overexpression attenuated LPS-stimulated inflammation and ALI through MAPK signaling pathway. PRKCA silencing attenuated EGCG protection. Within LPS-induced RAW 264.7 macrophages, EGCG could induce PRKCA expression. Single EGCG treatment or Lv-PRKCA infection attenuated LPS-induced increases in inflammatory factors; PRKCA silencing could reverse the suppressive effects of EGCG upon LPS-stimulated inflammatory factor release. In conclusion, EGCG pretreatment inhibits LPS-induced ALI in mice. The protective mechanism might be associated with the inhibitory effects of PRKCA on proinflammatory cytokine release via macrophages and MAPK signaling pathway.

Triptolide dose-dependently improves LPS-induced alveolar hypercoagulation and fibrinolysis inhibition through NF-κB inactivation in ARDS mice

BACKGROUND

Alveolar hypercoagulation and fibrinolysis inhibition were associated with the refractory hypoxemia and the high mortality in patient with acute respiratory distress syndrome (ARDS), and NF-κB pathway was confirmed to contribute to the process. Triptolide (TP) significantly inhibited NF-κB pathway and thus depressed accessive inflammatory response in ARDS. We speculate that TP could improve alveolar hypercoagulation and fibrinolytic inhibition in LPS-induced ARDS via NF-κB inactivation.

PURPOSE

The aim of this experiment was to explore the efficacy and potential mechanism of TP on alveolar hypercoagulation and fibrinolysis inhibition in LPS-induced ARDS in mice.

METHODS

50 μl of LPS (5 mg/ml) was inhalationally given to C57BL/6 mice to set up ARDS model. Male mice were randomly accepted with LPS, LPS + TP (1 μg/kg, 10 μg/kg, 50 μg/kg respectively), or with NEMO Binding domain peptide (NBD), an inhibitor of NF-κB. TP (1 μg/kg, 10 μg/kg, 50 μg/kg) were intraperitoneally injected or 10 μg/50 μl of NBD solution were inhaled 30 min before LPS inhalation. A same volume of normal saline (NS) substituted for TP in mice in control. The endpoint of experiment was at 8 hours after LPS stimulation. Pulmonary tissues were taken for hematoxylin-eosin (HE) staining, wet / dry ratio and for lung injury scores (LIS). Tissue factor (TF) and plasminogen activator inhibitor (PAI)-1 in lung tissue were detected by Western-blotting and by quantitative Real-time PCR(qPCR) respectively. Concentrations of TF, PAI-1, thrombin-antithrombin complex (TAT), procollagen peptide type Ⅲ (PⅢP) and activated protein C (APC) in bronchoalveolar lavage fluid (BALF) were measured by ELISA. NF-κB activation and p65-DNA binding activity in pulmonary tissue were simultaneously determined.

RESULTS

LPS stimulation resulted in pulmonary edema, neutrophils infiltration, obvious alveolar collapse, interstitial congestion, with high LIS, which were all dose-dependently ameliorated by Triptolide. LPS also dramatically promoted the expressions of TF and PAI-1 either in mRNA or in protein in lung tissue, and significantly stimulated the secretions of TF, PAI-1, TAT, PⅢP but inhibited APC production in BALF, which were all reversed by triptolide treatment in dose-dependent manner. TP dose-dependently inhibited the activation of NF-κB pathway induced by LPS, indicated by the changes of phosphorylations of p65 (p-p65), p-IKKα/β and p-IκBα, and weakened p65-DNA binding activity. TP and NBD had same efficacies either on alveolar hypercoagulation and fibrinolysis inhibition or on NF-κB signalling pathway in ARDS mice.

CONCLUSIONS

TP dose-dependently improves alveolar hypercoagulation and fibrinolysis inhibition in ARDS mice through inhibiting NF-κB signaling pathway. Our data demonstrate that TP is expected to be an effective selection in ARDS.

Triptolide Modulates the Expression of Inflammation-Associated lncRNA-PACER and lincRNA-p21 in Mycobacterium tuberculosis-Infected Monocyte-Derived Macrophages

Triptolide is a diterpene triepoxide, which performs its biological activities via mechanisms including induction of apoptosis, targeting of pro-inflammatory cytokines, and reshaping of the epigenetic landscape of target cells. However, the targeting of long non-coding RNAs (lncRNAs) by triptolide has not yet been investigated, despite their emerging roles as key epigenetic regulators of inflammation and immune cell function during Mycobacterium tuberculosis (Mtb) infection. Hence, we investigated whether triptolide targets inflammation-associated lncRNA-PACER and lincRNA-p21 and how this targeting associates with Mtb killing within monocyte-derived macrophages (MDMs).Using RT-qPCR, we found that triptolide induced the expression of lincRNA-p21 but inhibited the expression of lncRNA-PACER in resting MDMs in a dose- and time-dependent manner. Moreover, Mtb infection induced the expression of lincRNA-p21 and lncRNA-PACER, and exposure to triptolide before or after Mtb infection led to further increase of Mtb-induced expression of these lncRNAs in MDMs. We further found that contrary to lncRNA-PACER, triptolide time- and dose-dependently upregulated Ptgs-2, which is a proximal gene regulated by lncRNA-PACER. Also, low-concentration triptolide inhibited the expression of cytokine IL-6, a known target of lincRNA-p21. Mtb infection induced the expression of IL-6 and Ptgs-2, and triptolide treatment further increased IL-6 but decreased Ptgs-2 expression in Mtb-infected MDMs. The inverse relation between the expression of these lncRNAs and their target genes is concordant with the conception that these lncRNAs mediate, at least partially, the cytotoxic and/or anti-inflammatory activities of triptolide in both resting and activated MDMs. Using the CFU count method, we found that triptolide decreased the intracellular growth of Mtb HN878. The alamarBlue assay showed that this decreased Mtb HN878 growth was not as a result of direct targeting of Mtb HN878 by triptolide, but rather evoking MDMs’ intracellular killing mechanisms which we speculate could include triptolide-induced enhancement of MDMs’ effector killing functions mediated by lncRNA-PACER and lincRNA-p21. Altogether, these results provide proof of the modulation of lncRNA-PACER and lincRNA-p21 expression by triptolide, and a possible link between these lncRNAs, the enhancement of MDMs’ effector killing functions and the intracellular Mtb-killing activities of triptolide. These findings prompt for further investigation of the precise contribution of these lncRNAs to triptolide-induced activities in MDMs.

Upregulation of matrix metalloproteinase 9 (MMP9)/tissue inhibitor of metalloproteinase 1 (TIMP1) and MMP2/TIMP2 ratios may be involved in lipopolysaccharide-induced acute lung injury

Objective

This study aimed to examine the changes and significance of matrix metalloproteinase 9 (MMP9), MMP2, tissue inhibitor of metalloproteinase 1 (TIMP1), and TIMP2 in rats with lipopolysaccharide (LPS)-induced acute lung injury (ALI).

Methods

Wistar rats were randomly divided into a control group (injected with saline) and an ALI group (injected with LPS), then subdivided into four time points (2, 6, 12, and 24 hours). Serum tumor necrosis factor alpha and interleukin-6 levels were detected by ELISA to investigate the inflammatory reaction after LPS injection. The degree of ALI was determined by hematoxylin–eosin staining of lung tissue, the lung wet/dry weight ratio, and pulmonary permeability index. Changes in lung MMP and TIMP protein and mRNA levels were detected by western blotting and quantitative real-time polymerase chain reaction.

Results

Changes in the ratios of MMP9/TIMP1 and MMP2/TIMP2 were consistent with and strongly positively associated with the lung wet/dry weight ratio, the pulmonary permeability index, and serum tumor necrosis factor alpha and interleukin-6 levels in the ALI group.

Conclusion

ALI induced by LPS may be related to upregulation of MMP9/TIMP1 and MMP2/TIMP2 ratios.

Toll-like Receptor 4 Gene Polymorphisms in Chinese Population After Allogeneic Hematopoietic Stem Cell Transplantation

Objectives::

Graft-versus-host disease (GVHD) is the most common complication after hematopoietic stem cell transplantation (HSCT) and remains to be a major cause of mortality. Activation of toll-like receptor 4 (TLR-4) by lipopolysaccharide induces the NF-κB signaling pathway to release critical proinflammatory cytokines and increases the recipient response to GVHD. In order to clarify the role of TLR-4 in the occurrence of acute GVHD after HSCT, we collected 208 samples from HSCT recipients and their human lecucyte antigen identical donors to test the hypothesis that TLR-4polymorphism in the recipients or donors influence the risk of acute GVHD in allogeneic HSCT recipients.

Methods::

TLR-4 Asp299Gly and Thr399Ile polymorphisms of each sample were examined by using DNA sequencing and polymerase chain reaction-restriction fragment length polymorphism methods.

Results::

No homozygous or heterozygous variant alleles of the Asp299Gly or Thr339Ile polymorphism were detected in any samples in our study. Our results demonstrate that TLR-4 Asp299Gly and Thr399Ile polymorphisms might be very rare in the Chinese population (Eastern China and Taiwan region).

Conclusion::

The results of this study cannot confirm the role of TLR-4 mutations in the pathogenesis of GVHD in humans, yet we reach a definite conclusion by a TLR-4 knockout murine GVHD model in our ongoing project.

Phospholipase D as a Potential Modulator of Metabolic Syndrome: Impact of Functional Foods

Significance: Cardiometabolic disorders (CMD) are composed of a plethora of metabolic dysfunctions such as dyslipidemia, nonalcoholic fatty liver disease, insulin resistance, and hypertension. The development of these disorders is highly linked to inflammation and oxidative stress (OxS), two metabolic states closely related to physiological and pathological conditions. Given the drastically rising CMD prevalence, the discovery of new therapeutic targets/novel nutritional approaches is of utmost importance. Recent Advances: The tremendous progress in methods/technologies and animal modeling has allowed the clarification of phospholipase D (PLD) critical roles in multiple cellular processes, whether directly or indirectly via phosphatidic acid, the lipid product mediating signaling functions. In view of its multiple features and implications in various diseases, PLD has emerged as a drug target. Critical Issues: Although insulin stimulates PLD activity and, in turn, PLD regulates insulin signaling, the impact of the two important PLD isoforms on the metabolic syndrome components remains vague. Therefore, after outlining PLD1/PLD2 characteristics and functions, their role in inflammation, OxS, and CMD has been analyzed and critically reported in the present exhaustive review. The influence of functional foods and nutrients in the regulation of PLD has also been examined. Future Directions: Available evidence supports the implication of PLD in CMD, but only few studies emphasize its mechanisms of action and specific regulation by nutraceutical compounds. Therefore, additional investigations are first needed to clarify the functional role of nutraceutics and, second, to elucidate whether targeting PLDs with food compounds represents an appropriate therapeutic strategy to treat CMD. Antioxid. Redox Signal. 34, 252-278.

Natural product derived phytochemicals in managing acute lung injury by multiple mechanisms

Acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome (ARDS) as common life-threatening lung diseases with high mortality rates are mostly associated with acute and severe inflammation in lungs. With increasing in-depth studies of ALI/ARDS, significant breakthroughs have been made, however, there are still no effective pharmacological therapies for treatment of ALI/ARDS. Especially, the novel coronavirus pneumonia (COVID-19) is ravaging the globe, and causes severe respiratory distress syndrome. Therefore, developing new drugs for therapy of ALI/ARDS is in great demand, which might also be helpful for treatment of COVID-19. Natural compounds have always inspired drug development, and numerous natural products have shown potential therapeutic effects on ALI/ARDS. Therefore, this review focuses on the potential therapeutic effects of natural compounds on ALI and the underlying mechanisms. Overall, the review discusses 159 compounds and summarizes more than 400 references to present the protective effects of natural compounds against ALI and the underlying mechanism.

BAY11-7082 inhibits the expression of tissue factor and plasminogen activator inhibitor-1 in type-II alveolar epithelial cells following TNF-α stimulation via the NF-κB pathway

Pulmonary inflammation strongly promotes alveolar hypercoagulation and fibrinolytic inhibition. NF-κB signaling regulates the expression of molecules associated with coagulation and fibrinolytic inhibition in type-II alveolar epithelial cells (AECII) stimulated by lipopolysaccharide. However, whether TNF-α-induced alveolar hypercoagulation and fibrinolysis inhibition is also associated with the NF-κB pathway remains to be determined. The aim of the present study was to determine whether BAY11-7082, an inhibitor of the NF-κB pathway, inhibits the expressions of tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1) in AECⅡ in response to TNF-α. Rat AECII were treated with BAY11-7082 for 24 h and stimulated with TNF-α for 1 h. The expression of TF and PAI-1 were determined using western blotting and reverse transcription-quantitative PCR. The concentrations of TF and PAI-1 in culture supernatant were also measured by ELISA. Moreover, levels of NF-κB p65 (p65), phosphorylated (p)-p65 (p-p65), inhibitor of NF-κB α (IκBα) and p-IκBα were also evaluated. Immunofluorescence was used to detect p65 levels in cell nuclei. TNF-α significantly promoted TF and PAI-1 expression either at the mRNA or protein level in AECII cells. Concentrations of TF and PAI-1 in supernatant also significantly increased upon TNF-α stimulation. Furthermore, TNF-α upregulated the levels of p-IκBα, p65, and p-p65 in the cytoplasm. Immunofluorescence analysis indicated that TNF-α increased p65 translocation from the cytoplasm to the nucleus. However, AECII pre-treated with BAY11-7082 expressed lower levels of TF and PAI-1 following TNF-α treatment. Levels of p-IκBα, p65 and p-p65 in the cytoplasm also decreased, and translocation of p65 from cytoplasm into the nucleus was inhibited by BAY11-7082 pretreatment. These findings suggest that BAY11-7082 improves the hypercoagulation and fibrinolytic inhibition induced by TNF-α in alveolar epithelial cells via the NF-κB signaling pathway. BAY11-7082 might represent a therapeutic option for alveolar hypercoagulation and fibrinolytic inhibition in acute respiratory distress syndrome.

Phytochemicals: Potential Therapeutic Interventions Against Coronavirus-Associated Lung Injury

Since the outbreak of coronavirus disease 2019 (COVID-19) in December 2019, millions of people have been infected and died worldwide. However, no drug has been approved for the treatment of this disease and its complications, which urges the need for finding novel therapeutic agents to combat. Among the complications due to COVID-19, lung injury has attained special attention. Besides, phytochemicals have shown prominent anti-inflammatory effects and thus possess significant effects in reducing lung injury caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Also, the prevailing evidence reveales the antiviral effects of those phytochemicals, including anti-SARS-CoV activity, which could pave the road in providing suitable lead compounds in the treatment of COVID-19. In the present study, candidate phytochemicals and related mechanisms of action have been shown in the treatment/protection of lung injuries induced by various methods. In terms of pharmacological mechanism, phytochemicals have shown potential inhibitory effects on inflammatory and oxidative pathways/mediators, involved in the pathogenesis of lung injury during COVID-19 infection. Also, a brief overview of phytochemicals with anti-SARS-CoV-2 compounds has been presented.

Oxycodone attenuates vascular leak and lung inflammation in a clinically relevant two-hit rat model of acute lung injury

BACKGROUND

Oxycodone is a synthetic opioid receptor agonist that exerts antinociceptive activity via κ-, μ- and δ-opioid receptors (KOR, MOR and DOR, respectively). Activation of MOR has been reported to provide protection against acute lung injury (ALI). We hypothesized that pretreatment with oxycodone would attenuate lung injury at the level of alveolar tight junctions (TJs) and aquaporins (AQPs) and investigated this possibility in a two-hit model of ALI induced by lipopolysaccharide (LPS) and mechanical ventilation (MV).

METHOD

Male Sprague Dawley rats and A59 cells were divided into 6 groups: the control group, ALI group, oxycodone-pretreated group, and oxycodone/κ-, μ-, or δ-opioid receptor antagonist-pretreated groups. The rats were pretreated with oxycodone 30 min before intravenous injection of LPS and then allowed to recover for 24 h prior to MV, establishing a two-hit model of ALI. The cells were similarly treated with oxycodone (with or without antagonists) 30 min after exposure to lipopolysaccharide. The cells were cyclically stretched 24 h later to mirror the in vivo MV protocol.

RESULTS

Oxycodone alleviated the histological lung changes in the rats with ALI and decreased pulmonary microvascular permeability both in vivo and in vitro. Oxycodone upregulated the expression of claudin-5, ZO-1, AQP1, and AQP5 but downregulated the expression of TNF-α, IL-1β, TLR4, NF-κB, MMP9, and caspase-3 and suppressed endothelial apoptosis in vivo and in vitro. These protective effects of oxycodone were partly eliminated by KOR and MOR antagonists but not by DOR antagonists.

CONCLUSION

Oxycodone pretreatment appears to act via κ- and μ-opioid receptors to ameliorate LPS- and MV-induced lung injury by suppressing inflammation and apoptosis, and this protective effect might be mediated through the inhibition of the TLR4/NF-κB pathways.

Tripterygium Ingredients for Pathogenicity Cells in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease mainly characterized by chronic polyarthritis. Many types of cells play pivotal roles in the pathogenicity of RA, such as T cells, B cells, macrophages, dendritic cells (DCs), osteoclasts (OCs), and fibroblast-like synoviocytes (FLS). Tripterygium wilfordii Hook f. (TwHf) and its ingredients are able to control disease activity by regulating the functions of cells mentioned above, and the clinical studies have highlighted the importance of TwHf ingredients in RA treatment. They have been demonstrated to improve the RA symptoms of animal models and patients. In this review, we discussed the effect of TwHf ingredients on pathogenicity cells, including disease/cell phenotypes and molecular mechanisms. Here, we constructed a cell-cell interaction network to visualize the effect of TwHf ingredients. We found that TwHf ingredients could inhibit the differentiation and proliferation of the pathogenicity cells. Besides, the components could decrease the levels of pathogenicity cytokines [i.e., interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α)]. Many signaling pathways are involved in the underlying mechanisms, such as PI3K, NF-κB, and MAPK signaling pathways.

Vimentin as a target for the treatment of COVID-19

We and others propose vimentin as a possible cellular target for the treatment of COVID-19. This innovative idea is so recent that it requires further attention and debate. The significant role played by vimentin in virus-induced infection however is well established: (1) vimentin has been reported as a co-receptor and/or attachment site for SARS-CoV; (2) vimentin is involved in viral replication in cells; (3) vimentin plays a fundamental role in both the viral infection and the consequent explosive immune-inflammatory response and (4) a lower vimentin expression is associated with the inhibition of epithelial to mesenchymal transition and fibrosis. Moreover, the absence of vimentin in mice makes them resistant to lung injury. Since vimentin has a twofold role in the disease, not only being involved in the viral infection but also in the associated life-threatening lung inflammation, the use of vimentin-targeted drugs may offer a synergistic advantage as compared with other treatments not targeting vimentin. Consequently, we speculate here that drugs which decrease the expression of vimentin can be used for the treatment of patients with COVID-19 and advise that several Food and Drug Administration-approved drugs be immediately tested in clinical trials against SARS-CoV-2, thus broadening therapeutic options for this type of viral infection.

MicroRNA‑17 contributes to the suppression of the inflammatory response in lipopolysaccharide‑induced acute lung injury in mice via targeting the toll‑like receptor 4/nuclear factor‑κB pathway

Acute lung injury (ALI) is a common lung disease with a high mortality rate, which is characterized by an excessive uncontrolled inflammatory response. MicroRNA (miR)-17 has previously emerged as a novel regulatory molecule of inflammatory response in various complex diseases; however, the anti-inflammatory action and associated molecular mechanisms of miR-17 in ALI have not been fully elucidated. The aim of the present study was to investigate the role of miR-17 in the inflammatory response in ALI and to elucidate the potential underlying mechanism. Using a lipopolysaccharide (LPS)-induced ALI mouse model, it was observed that miR-17 was significantly downregulated in lung tissues compared with the control group. In this model, ectopic expression of miR-17 attenuated lung pathological damage, reduced lung wet/dry ratio and lung permeability, and increased survival rate in ALI mice. In addition, agomiR-17 injection significantly suppressed LPS-induced inflammation, as evidenced by a reduction in the activity of myeloperoxidase and the production of interleukin (IL)-6, IL-1β and tumor necrosis factor-α in lung tissues. Of note, toll-like receptor (TLR) 4, an upstream regulator of the nuclear factor (NF)-κB inflammatory signaling pathway, was directly targeted by miR-17, and its translation was suppressed by miR-17 in vitro and in vivo. Using an LPS-induced RAW264.1 macrophage injury model, it was observed that miR-17 overexpression suppressed the pro-inflammatory effect of LPS, while these inhibitory effects were markedly abrogated by TLR4 overexpression. In addition, TLR4 knockdown by si-TLR4 mimicked the effects of miR-17 overexpression on LPS-induced cytokine secretion in the in vitro model. Further experiments revealed that miR-17 significantly reduced the expression of key proteins in the NF-κB pathway, including IKKβ, p-IκBα and nuclear p-p65, and suppressed the NF-κB activity in ALI mice. Collectively, these results indicated that miR-17 protected mice against LPS-induced lung injury via inhibiting inflammation by targeting the TLR4/NF-κB pathway; therefore, miR-17 may serve as a potential therapeutic target for ALI.

Triptolide alleviates radiation-induced pulmonary fibrosis via inhibiting IKKβ stimulated LOX production

Lysyl oxidase (LOX) is involved in fibrosis by catalyzing collagen cross-linking. Previous work observed that Triptolide (TPL) alleviated radiation-induced pulmonary fibrosis (RIPF), but it is unknown whether the anti-RIPF effect of TPL is related to LOX. In a mouse model of RIPF, we found that LOX persistently increased in RIPF which was significantly lowered by TPL. Excessive LOX aggravated fibrotic lesions in RIPF, while LOX inhibition mitigated RIPF. Irradiation enhanced the transcription and synthesis of LOX by lung fibroblasts through IKKβ/NFκB activation, and siRNA knockdown IKKβ largely abolished LOX production. By interfering radiation induced IKKβ activation, TPL prevented NFκB nuclear translocation and DNA binding, and potently decreased LOX synthesis. Our results demonstrate that the anti-RIPF effect of TPL is associated with reduction of LOX production which mediated by inhibition of IKKβ/NFκB pathway.

A new perspective of triptolide-associated hepatotoxicity: the relevance of NF- B and NF- B-mediated cellular FLICE-inhibitory protein

Previously, we proposed a new perspective of triptolide (TP)-associated hepatotoxicity: liver hypersensitivity upon lipopolysaccharide (LPS) stimulation. However, the mechanisms for TP/LPS-induced hepatotoxicity remained elusive. The present study aimed to clarify the role of LPS in TP/LPS-induced hepatotoxicity and the mechanism by which TP induces liver hypersensitivity upon LPS stimulation. TNF-α inhibitor, etanercept, was injected intraperitoneally into mice to investigate whether induction of TNF-α by LPS participated in the liver injury induced by TP/LPS co-treatment. Mice and hepatocytes pretreated with TP were stimulated with recombinant TNF-α to assess the function of TNF-α in TP/LPS co-treatment. Additionally, time-dependent NF-κB activation and NF-κB-mediated pro-survival signals were measured in vivo and in vitro. Finally, overexpression of cellular FLICE-inhibitory protein (FLIP), the most potent NF-κB-mediated pro-survival protein, was measured in vivo and in vitro to assess its function in TP/LPS-induced hepatotoxicity. Etanercept counteracted the toxic reactions induced by TP/LPS. TP-treatment sensitized mice and hepatocytes to TNF-α, revealing the role of TNF-α in TP/LPS-induced hepatotoxicity. Mechanistic studies revealed that TP inhibited NF-κB dependent pro-survival signals, especially FLIP, induced by LPS/TNF-α. Moreover, overexpression of FLIP alleviated TP/LPS-induced hepatotoxicity in vivo and TP/TNF-α-induced apoptosis in vitro. Mice and hepatocytes treated with TP were sensitive to TNF-α, which was released from LPS-stimulated immune cells. These and other results show that the TP-induced inhibition of NF-κB-dependent transcriptional activity and FLIP production are responsible for liver hypersensitivity.

Up-regulation of microRNA-574 attenuates lipopolysaccharide- or cecal ligation and puncture-induced sepsis associated with acute lung injury

Acute lung injury (ALI) is the most vulnerable organ in sepsis, however, its underlying mechanism remains unclear. Cell viability and apoptosis were detected by cell counting kit-8 and flow cytometry. The expressions of miR-574, Complement 3 (C3), glucose regulatory protein 78 (GRP78), C/EBP homologous protein (CHOP) and Caspase-12 were determined using quantitative real time (qRT)-PCR and Western blot. Histopathology of mice was stained by haematoxylin and eosin staining. The levels of tumour necrosis factor-α (TNF-α) and interleukin (IL)-1β were determined using ELISA. The expression of miR-574 was positively correlated with cell viability in lipopolysaccharide (LPS)-treated cells. Cell viability was improved and apoptosis was inhibited by mimics. Meanwhile, the levels of GRP78, CHOP and Caspase-12 were suppressed by mimics and agomir in LPS-treated human bronchial epithelial (HBE) cells and cecal ligation and puncture (CLP)-treated mice. In vivo, lung tissue damages were ameliorated by agomir, which also decreased the levels of neutrophils, macrophages and albumin. C3 was a target gene of miR-574 and could be decreased by mimics. SiC3 enhanced cell viability and inhibited apoptosis, however, it suppressed the mRNA levels of GRP78, CHOP and Caspase-12. Up-regulation of miR-574 attenuated sepsis-induced lung injury may be by promoting C3 down-regulation and reducing sepsis-induced endoplasmic reticulum stress (ERS). SIGNIFICANCE OF THE STUDY: Clinically, the mortality rate of ALI induced by sepsis remains at a high level, thus, clarifying the mechanism of induction of ALI through pathogen infection will provide a new target for clinical treatment of ALI. In this study, up-regulation of miR-574 attenuated sepsis-induced lung injury may be by promoting C3 down-regulation and reducing sepsis-induced ERS. Our study provides a deeper understanding of sepsis.

MicroRNA-182 supplies negative feedback regulation to ameliorate lipopolysaccharide-induced ALI in mice by targeting TLR4

Acute lung injury (ALI), characterized by increased excessive pulmonary inflammation, is a pervasive inflammatory disease with clinically high incidence. MicroRNA (miRNAs) have been associated with the progression of multiple diseases and are regarded as novel regulators of inflammation. However, it remains largely unknown whether the miRNAs-mediated regulatory mechanism has an effect on lipopolysaccharide (LPS)-induced inflammation in ALI. We discovered that miR-182 distinctly lessened expression in the lung tissue of mice with ALI and macrophages stimulated by LPS. We also found that overexpression of miR-182 significantly cut down the secretion of inflammatory cytokines, while this change was reversed by inhibition of miR-182. In addition, miR-182 suppressed the activation of NF-κB by targeting TLR4 expression. And it was confirmed that miR-182 directly regulated TLR4 expression at the posttranscriptional level by binding to the 3'-UTR of TLR4. Together, these data suggested that inhibition of TLR4 expression assuaged LPS-stimulated inflammation through negative feedback regulation of miR-182.

The role of hypertriglyceridemia and treatment patterns in the progression of IgA nephropathy with a high proportion of global glomerulosclerosis

PURPOSE

Many studies have focused on finding predictors for mild IgAN progression. However, the cases of severe IgAN with a high proportion of global glomerulosclerosis have received inadequate attention.

METHODS

A group of 172 primary IgAN patients with 50-75% global glomerulosclerosis was studied retrospectively between April 2007 and October 2017. Patients were divided into three groups according to the serum triglyceride tertiles:  < 1.42 µmol/L (Group 1), 1.42-2.29 µmol/L (Group 2), and > 2.29 µmol/L (Group 3). Groups 1 and 2 comprised non-hypertriglyceridemia subjects, while Group 3 was defined as the hypertriglyceridemia (HTG) group. The patients were followed for 4-96 months (median 39.43 months). The study end point was defined as a 50% decline in estimated glomerular filtration rate (eGFR) or ESRD.

RESULTS

A high proportion of global glomerulosclerosis is not absolutely correlated with severe clinical features and poor renal outcome. In our retrospective observation, eGFR decreased by less than 10% of the baseline during follow-up in 43.6% of the patients. However, in our patients with HTG, the cumulative renal survival rate was significantly lower compared to those without HTG. Multivariate Cox regression analysis also showed that triglyceride is an independent predictor of poor renal outcomes. Furthermore, in the HTG group, the cumulative renal survival rates were higher in patients treated with Tripterygium wilfordii Hook F (TwHF) compared to those without TwHF.

CONCLUSIONS

A high proportion of global glomerulosclerosis combined with HTG at biopsy have better predictive validity for the disease progression of IgAN than global glomerulosclerosis alone. TwHF may partially affect the renal outcome of severe IgAN with HTG, and this may relate to its regulation of lipid metabolism and immunoinflammatory response.

Advances in research into the mechanisms of Chinese Materia Medica against acute lung injury

Acute lung injury (ALI) is a common and serious disease. Numerous treatment options are available but they do not improve quality of life or reduce mortality for ALI patients. Here, we review the treatments for ALI to provide basic data for ALI drug therapy research and development. Chinese Materia Medica (CMM) has long been the traditional clinical approach in China for the treatment of ALI and it has proven efficacy. The continued study of CMM has disclosed new potential therapeutic ingredients for ALI. However, few reviews summarize the currently available CMM-based anti-ALI drugs. Therefore, the systematic analysis of research progress in anti-ALI CMM is of great academic and clinical value. The aim of the present review is to describe CMM-based research progress in ALI treatment. Data were compiled by electronic retrieval (CNKI, SciFinder, PubMeds, Google Scholar, Web of Science) and from articles, patents and ethnopharmacological literature in university libraries were systematically studied. This review introduces progress in research on the etiology and mechanisms of ALI, the anti-ALI theory and modes of action in traditional Chinese medicine (TCM), anti-ALI active constituents of CMM, research progress in experimental methods of CMM anti-ALI, the anti-ALI molecular mechanisms of CMM, the anti-ALI efficacy of CMM formulae, and the potential toxicity of CMM and the antidotes for it. Scholars have investigated the anti-ALI molecular mechanism of CMM from various direction and have made substantial progress. This research explored the above aspects, enriched the anti-ALI theory of CMM and established the clinical significance and developmental prospects of ALI treatment by CMM. Because of the high frequency of drugs such as glucocorticoids or antibiotics, Western medicine lacks the advantages of CMM in terms of overall anti-ALI efficacy. In the future, the development of CMM-based anti-ALI therapies will become a major trend in the field of ALI drug development. Successful clinical safety and efficacy validations will promote and encourage the use of CMM. It provides fundamental theoretical support for the discovery and use of CMM resources through the comprehensive analysis of various anti-ALI CMM report databases.

Synergistic effect of all-trans-retinal and triptolide encapsulated in an inflammation-targeted nanoparticle on collagen-induced arthritis in mice

Targeted delivery of nano-encapsulated anti-inflammatory agent represents a promising while challenging strategy in the treatment of rheumatoid arthritis (RA). Pro-inflammatory macrophages play a major role in the pathogenesis of RA. In this study, we investigated the effect of a macrophage-targeted pH-sensitive nanoparticle on collagen-induced arthritis (CIA) in mice. To target macrophage, all-trans-retinal was conjugated into dextran backbone through pH-sensitive hydrazone bond, then grafted with galactose (GDR). This nanoparticle was used for the encapsulation of triptolide (TPT), a potent anti-inflammatory compound isolated from Chinese herb. As expected, GDR nanoparticles preferentially accumulated in the inflammatory tissues. Treatment with GDR-TPT nanoparticles resulted in a marked decrease in the infiltration of CD3⁺ T cells and F4/80⁺ macrophages and reduction of the expression of TNF-α, IL-6 and IL-1β in the inflamed lesions of CIA mice. Furthermore, Th1 and Th17 responses were also inhibited. Importantly, anti-arthritic effect of TPT was markedly enhanced while its toxic effect was attenuated by encapsulating with GDR. GDR by itself also had moderate effect in the inhibition of arthritis, due to its intrinsic anti-inflammatory property. Therefore, our results clearly show that GDR-TPT nanoparticle may represent a promising drug delivery system for the treatment of RA.

Synergistic effect of halofuginone and dexamethasone on LPS‑induced acute lung injury in type II alveolar epithelial cells and a rat model

Acute lung injury (ALI) is characterized by neutrophilic infiltration, uncontrolled oxidative stress and inflammatory processes. Despite various therapeutic regimes having been performed, there remains no effective pharmacotherapy available to treat ALI. Halofuginone (HF), a ketone isolated from Dichroa febrifuga, exhibits significant anti‑inflammatory and antifibrotic effects. Dexamethasone (DEX), a synthetic glucocorticoid, has been routinely used as an adjuvant therapy in treating inflammatory diseases, including ALI. The present study aimed to investigate the effects of the combination of HF and DEX in the treatment of ALI. The present results suggested that the simultaneous administration of HF and DEX markedly decreased the level of pro‑inflammatory cytokines and increased the level of anti‑inflammatory cytokines, as assessed by western blot analysis. In addition, HF and DEX effectively decreased nuclear factor‑κB activity via suppressing the phosphorylation of P65 in lipopolysaccharide (LPS)‑induced human pulmonary alveolar epithelial cells (HPAEpiC) and lung tissues extracted from ALI rats, as determined by immunofluorescence. Furthermore, in vivo experiments demonstrated that the combination of HF and DEX in LPS‑induced ALI rats defended against lung fibrosis, perivascular inflammation, congestion and edema of pulmonary alveoli, as assessed by histopathological analysis, TUNEL staining and immunohistochemistry assay. Taken together, the present study indicated the synergistic effect of HF and DEX on LPS‑induced ALI in HPAEpiC cells and a rat model. These results offer a novel therapeutic approach for the treatment of ALI.

Application and Mechanisms of Triptolide in the Treatment of Inflammatory Diseases-A Review

Bioactive compounds from medicinal plants with anti-inflammatory and immunosuppressive effects have been emerging as important sources of drugs for the treatment of inflammatory disorders. Triptolide, a diterpene triepoxide, is a pharmacologically active compound isolated from Tripterygium wilfordii Hook F (TwHF) that is used as a remedy for inflammatory and autoimmune diseases. As the most promising bioactive compound obtained from TwHF, triptolide has attracted considerable interest recently, especially for its potent anti-inflammatory and immunosuppressive activities. Over the past few years, an increasing number of studies have been published emphasizing the value of triptolide in the treatment of diverse inflammatory disorders. Here, we systematically review the mechanism of action and the therapeutic properties of triptolide in various inflammatory diseases according to different systematic organs, including lupus nephritis, inflammatory bowel disease, asthma, and rheumatoid arthritis with pubmed and Embase. Based on this review, potential research strategies might contribute to the clinical application of triptolide in the future.

Epigallocatechin-3-gallate ameliorates lipopolysaccharide-induced acute lung injury by suppression of TLR4/NF-κB signaling activation

Acute lung injury (ALI) is a serious clinical syndrome with a high rate of mortality. The activation of inflammation is well-recognized as a vital factor in the pathogenesis of lipopolysaccharide (LPS)-induced ALI. Therefore, suppression of the inflammatory response could be an ideal strategy to prevent ALI. Epigallocatechin-3-gallate (EGCG), mainly from green tea, has been shown to have an anti-inflammatory effect. The aim of the study was to explore whether EGCG alleviates inflammation in sepsis-related ALI. Male BALB/C mice were treated with EGCG (10 mg/kg) intraperitoneally (ip) 1 h before LPS injection (10 mg/kg, ip). The results showed that EGCG attenuated LPS-induced ALI as it decreased the changes in blood gases and reduced the histological lesions, wet-to-dry weight ratios, and myeloperoxidase (MPO) activity. In addition, EGCG significantly decreased the expression of pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in the lung, serum, and bronchoalveolar lavage fluid, and alleviated the expression of TLR-4, MyD88, TRIF, and p-p65 in the lung tissue. In addition, it increased the expression of IκB-α and had no influence on the expression of p65. Collectively, these results demonstrated the protective effects of EGCG against LPS-induced ALI in mice through its anti-inflammatory effect that may be attributed to the suppression of the activation of TLR 4-dependent NF-κB signaling pathways.

MiR-27 alleviates myocardial cell damage induced by hypoxia/reoxygenation via targeting TGFBR1 and inhibiting NF-κB pathway

MiR-27 prevents atherosclerosis by inhibiting inflammatory responses induced by lipoprotein lipase. Overexpression of miR-27b attenuates angiotensin-induced atrial fibrosis. Nevertheless, studies have rarely investigated on the effect of miR-27 in cardiomyocyte injury. H9c2 cells were transfected with miR-27 mimic/inhibitor. Then the cell proliferation was tested by MTT assay and the cell apoptosis was detected by flow cytometry. The luciferase activity assay was utilized to analyze the relationship between miR-27 and TGFBR1. Quantificational real-time polymerase chain reaction and western blot were utilized to detect the cardiomyocyte differentiation marker and nuclear factor kappa B (NF-κB) pathway. Our outcomes demonstrated that miR-27 expression was downregulated cardiomyocyte injury subjected to hypoxia/reoxygenation (H/R). Additionally, overexpression of miR-27 could significantly alleviate cardiomyocyte injury by regulating cell activity and apoptosis. The luciferase activity assay confirmed that transforming growth factor ß receptor 1 (TGFBR1) is a direct hallmark of miR-27. Besides, overexpression of miR-27 promoted the expression of TGFBR1 in H/R model. After transfection with miR-27 mimic/inhibitor, the expression of NF-κB pathway-related proteins was decreased/increased. Taken together, our data manifested that miR-27 repressed cardiomyocyte injury induced by H/R via mediating TGFBR1 and inhibiting NF-κB signaling pathway. Furthermore, miR-27/ TGFBR1 might be utilized as hopeful biomarkers for myocardial ischemia diagnosis and treatment.

MicroRNA expression, targeting, release dynamics and early-warning biomarkers in acute cardiotoxicity induced by triptolide in rats

Tripterygium wilfordii Hook. F. is a plant used in traditional Chinese medicine to treat rheumatoid arthritis, lupus erythematosus, and psoriasis in China. However, its main active substance, triptolide, has toxic effects on the heart, liver, and kidneys, which limit its clinical application. Therefore, determining the mechanism of cardiotoxicity in triptolide and identifying effective early-warning biomarkers is beneficial for preventing irreversible myocardial injury. We observed changes in microRNAs and aryl hydrocarbon receptor (AhR) as potential biomarkers in triptolide-induced acute cardiotoxicity by using techniques such as polymerase chain reaction (PCR) assay. The results revealed that triptolide increased the heart/body ratio and caused myocardial fiber breakage, cardiomyocyte hypertrophy, increased cell gaps, and nuclear dissolution in treated male rats. Real-time PCR array detection revealed a more than 2-fold increase in the expression of 108 microRNA genes in the hearts of the male rats; this not only regulated the signaling pathways of ErbB, FOXO, AMPK, Hippo, HIF-1α, mTOR, and PI3K-Akt but also participated in biological processes such as cell adhesion, cell cycling, action potential, locomotory behavior, apoptosis, and DNA binding. Moreover, triptolide reduced the circulatory and cardiac levels of AhR protein as a target of these microRNAs and the messenger RNA expression of its downstream gene CYP1 A1. However, decreases in myocardial lactate dehydrogenase, creatine kinase MB, catalase, and glutathione peroxidase activity and an increase in circulating cardiac troponin I were observed only in male rats. Moreover, plasma microRNAs exhibited dynamic change. These results revealed that circulating microRNAs and AhR protein are potentially early-warning biomarkers for triptolide-induced cardiotoxicity.

Upregulation of miRNA-140-5p inhibits inflammatory cytokines in acute lung injury through the MyD88/NF-κB signaling pathway by targeting TLR4

The present study was designed to determine the effect of miR-140-5p on acute lung injury (ALI) and the associated inflammation induced. As a result, miR-140-5p expression in mice with ALI was suppressed when compared with the normal group. Downregulation of miR-140-5p increased the levels of inflammatory factors induced by ALI [including tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and myeloperoxidase] in an in vitro model of human lung A549 cells. Downregulation of miR-140-5p also induced the protein expression of Toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88) and nuclear factor (NF)-κB in an in vitro model. Overexpression of miR-140-5p reduced the levels of inflammation in the in vitro model of ALI via the suppression of the TLR4/MyD88/NF-κB signaling pathway. The inhibition of TLR4 using a TLR4 inhibitor reduced the proinflammation effects of anti-miR-140-5p in the in vitro model of ALI. The NF-κB inhibitor also inhibited the proinflammation effects of anti-miR-140-5p in the in vitro model of ALI. Overall, the results of the present study indicated that miR-140-5p inhibited ALI-induced inflammation via the TLR4/MyD88/NF-κB signaling pathway.

Triptolide exhibits antitumor effects by reversing hypermethylation of WIF‑1 in lung cancer cells

Triptolide (TP) exhibits numerous biological activities, including immunosuppressive, anti‑inflammatory and antitumor effects. The aim of the present study was to investigate the role of TP as a potent therapeutic drug for the treatment of lung cancer and to investigate the underlying therapeutic mechanisms. Western blot analyses and reverse transcription‑quantitative polymerase chain reaction (PCR) were performed to investigate the expression of genes at transcriptional and translational levels, respectively. Methylation‑specific PCR assays were conducted to investigate whether TP affects the Wnt inhibitory factor‑1 (WIF‑1) methylation status and subsequently affects apoptosis, migration or the invasion of lung cancer cells. The results of the present study revealed that the methylation status of WIF‑1 in lung cancer cell lines A549 and H460 was significantly enhanced compared with the human normal bronchial epithelial cell line HBE, whereas treatment with TP was revealed to induce the demethylation of WIF‑1. The present study aimed to investigate whether the biological activities of TP are regulated by inhibiting the Wnt signaling pathway via an increase in WIF‑1 expression levels. The results of the present study revealed that Wnt signaling was suppressed in cells following treatment with TP, which was concluded by the downregulation of Axin 2 and β‑catenin expression. Further investigation demonstrated that the silencing of WIF‑1 expression with small interfering RNA reversed the TP‑induced upregulation of WIF‑1 expression, upregulated Axin 2 and β‑catenin expression and enhanced the activation of Wnt signaling. Notably, an upregulation of cellular tumor antigen p53 expression, and downregulation of matrix metalloproteinase‑9 (MMP‑9) and phosphorylated‑nuclear factor‑κB (NF‑κB) P65 (p‑P65) levels was observed following TP treatment. These results suggest that the Wnt, p53 and NF‑κB signaling pathways mediate the potent antitumor effects of TP. Notably, the silencing of WIF‑1 did not completely recover the levels of p53, MMP‑9 and p‑P65 in cells treated with TP compared with the control cells, thus suggesting that TP exhibits further functions in addition to the targeting of WIF‑1.

Triptolide inhibits vascular endothelial growth factor-mediated angiogenesis in human breast cancer cells

Triptolide has been demonstrated to induce tumor cell apoptosis. However, the role of triptolide in breast cancer angiogenesis remains unclear. The present study aimed to investigate the function of triptolide in breast cancer and the molecular mechanisms underlying this. The results revealed that triptolide could significantly decrease the expression of vascular endothelial growth factor A (VEGFA) in Hs578T and MDAMB231 breast cancer cells. Furthermore, human umbilical vein endothelial cells were used to perform tube formation and bromodeoxyuridine incorporation assays, which demonstrated an antiangiogenic effect of triptolide. In addition, the effect of triptolide in vivo was examined in a xenograft mouse model, which determined that VEGFA, cluster of differentiation 31 and anti-proliferation marker protein Ki67 expression in tumor sections was decreased in the triptolide treatment group compared with the control group. Western bolt analysis was performed to investigate the phosphorylation of extracellular signal-related kinase (ERK)1/2 and RAC-α serine/threonine-protein kinase after triptolide treatment, and it's effect on hypoxia inducible factor (HIF)1-α expression. The results demonstrated that triptolide suppressed ERK1/2 activation and HIF1-α expression. Furthermore, overexpression of HIF1-α could partially abrogate the inhibitory effect of triptolide on VEGFA expression. These results suggest that triptolide inhibits breast cancer cell angiogenesis in vitro and in vivo through inhibiting the ERK1/2-HIF1-α-VEGFA axis.

A Mechanistic Overview of Triptolide and Celastrol, Natural Products from Tripterygium wilfordii Hook F

Triptolide and celastrol are predominantly active natural products isolated from the medicinal plant Tripterygium wilfordii Hook F. These compounds exhibit similar pharmacological activities, including anti-cancer, anti-inflammation, anti-obesity, and anti-diabetic activities. Triptolide and celastrol also provide neuroprotection and prevent cardiovascular and metabolic diseases. However, toxicity restricts the further development of triptolide and celastrol. In this review, we comprehensively review therapeutic targets and mechanisms of action, and translational study of triptolide and celastrol. We systemically discuss the structure-activity-relationship of triptolide, celastrol, and their derivatives. Furthermore, we propose the use of structural derivatives, targeted therapy, and combination treatment as possible solutions to reduce toxicity and increase therapeutic window of these potent natural products from T. wilfordii Hook F.

Triptolide Inhibits Proliferation and Migration of Human Neuroblastoma SH-SY5Y Cells by Upregulating MicroRNA-181a

Neuroblastoma is the primary cause of cancer-related death for children 1 to 5 years of age. New therapeutic strategies and medicines are urgently needed. This study aimed to investigate the effects of triptolide (TPL), the major active component purified from Tripterygium wilfordii Hook F, on neuroblastoma SH-SY5Y cell proliferation, migration, and apoptosis, as well as underlying potential mechanisms. We found that TPL inhibited SH-SY5Y cell viability, proliferation, and migration, but induced cell apoptosis. The expression of matrix metalloproteinase-2 (MMP-2) and MMP-9 after TPL treatment in SH-SY5Y cells was decreased. The expression of microRNA-181a (miR-181a) was upregulated after TPL treatment. Moreover, suppression of miR-181a reversed the effects of TPL on SH-SY5Y cell proliferation, apoptosis, and migration. Overexpression of miR-181a enhanced the TPL-induced activation of p38 mitogen-activated protein kinase (p38MAPK) and nuclear factor κ light chain enhancer of activated B cells (NF-κB) pathways. In conclusion, our research verified that TPL inhibited the proliferation and migration of human neuroblastoma SH-SY5Y cells by upregulating the expression of miR-181a.

3, 4-dihydroxybenzalacetone attenuates lipopolysaccharide-induced inflammation in acute lung injury via down-regulation of MMP-2 and MMP-9 activities through suppressing ROS-mediated MAPK and PI3K/AKT signaling pathways

3, 4-Dihydroxybenzalacetone (DBL) is a constituent of Phellinus linteus. This study demonstrated the protective effect of DBL on lipopolysaccharide (LPS)-induced acute lung injuries in mice. Pretreatment with DBL significantly improved LPS-induced histological alterations in lung tissues. In addition, DBL markedly reduced the total cell number, the leukocytes, the protein concentrations, and decreased the release of nitrite, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and the activities of matrix metalloproteinase (MMP)-2 and -9 in the bronchoalveolar lavage fluid. DBL also inhibited the W/D ratio and myeloperoxidase activity in the lung tissues. Western blot analysis indicated DBL efficiently blocked the protein expressions of inducible nitric oxide synthase, cyclooxygenase-2, MMP-2, MMP-9, and the phosphorylation of mitogen-activated protein kinase (MAPK), phosphoinositide-3-kinase (PI3K), AKT, Toll-like receptor 4 (TLR4) and nuclear factor (NF)-κB. Moreover, DBL enhanced the expression of anti-oxidant proteins, such as superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx). Based on our results, DBL might be a potential target for attenuating tissue oxidative injuries and nonspecific pulmonary inflammation.

Triptolide induced cell death through apoptosis and autophagy in murine leukemia WEHI-3 cells in vitro and promoting immune responses in WEHI-3 generated leukemia mice in vivo

Triptolide, a traditional Chinese medicine, obtained from Tripterygium wilfordii Hook F, has anti-inflammatory, antiproliferative, and proapoptotic properties. We investigated the potential efficacy of triptolide on murine leukemia by measuring the triptolide-induced cytotoxicity in murine leukemia WEHI-3 cells in vitro. Results indicated that triptolide induced cell morphological changes and induced cytotoxic effects through G0/G1 phase arrest, induction of apoptosis. Flow cytometric assays showed that triptolide increased the production of reactive oxygen species, Ca²⁺ release and mitochondrial membrane potential (ΔΨ_m ), and activations of caspase-8, -9, and -3. Triptolide increased protein levels of Fas, Fas-L, Bax, cytochrome c, caspase-9, Endo G, Apaf-1, PARP, caspase-3 but reduced levels of AIF, ATF6α, ATF6β, and GRP78 in WEHI-3 cells. Triptolide stimulated autophagy based on an increase in acidic vacuoles, monodansylcadaverine staining for LC-3 expression and increased protein levels of ATG 5, ATG 7, and ATG 12. The in vitro data suggest that the cytotoxic effects of triptolide may involve cross-talk between cross-interaction of apoptosis and autophagy. Normal BALB/c mice were i.p. injected with WEHI-3 cells to generate leukemia and were oral treatment with triptolide at 0, 0.02, and 0.2 mg/kg for 3 weeks then animals were weighted and blood, liver, spleen samples were collected. Results indicated that triptolide did not significantly affect the weights of animal body, spleen and liver of leukemia mice, however, triptolide significant increased the cell populations of T cells (CD3), B cells (CD19), monocytes (CD11b), and macrophage (Mac-3). Furthermore, triptolide increased the phagocytosis of macrophage from peripheral blood mononuclear cells (PBMC) but not effects from peritoneum. Triptolide promoted T and B cell proliferation at 0.02 and 0.2 mg/kg treatment when cells were pretreated with Con A and LPS stimulation, respectively; however, triptolide did not significant affect NK cell activities in vivo. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 550-568, 2017.

Triptolide inhibits the progression of atherosclerosis in apolipoprotein E-/- mice

Atherosclerosis, the major cause of cardiovascular disease, is accompanied by a chronic inflammatory response during the disease. Triptolide (TPL) is an active natural compound that has been demonstrated to possess anti-inflammatory activities in various cell types. However, the effects of TPL on atherosclerosis have not yet been studied. The goal of the present study was to determine the effects of TPL on apolipoprotein E knock-out (ApoE^-/^-) mice fed with a high-fat diet and to analyze the changes in lipid metabolism and inflammatory cytokines to clarify the underlying molecular mechanisms. Firstly, the genotypes of ApoE^-/^- mice and corresponding wild-type mice were identified using polymerase chain reaction. The ApoE^-/^- mice were randomly divided into four groups: ApoE^-/^- model mice, and ApoE^-/^- mice treated with 25, 50 or 100 µg/kg TPL every twice day. Wild-type mice with the same genetic background constituted the fifth group. The mice in each group were given a high-fat diet from week 8 after birth until week 20. Total cholesterol and total triglyceride levels were determined at 16 and 20 weeks. The results demonstrated that the levels of total cholesterol and total triglyceride in the plasma were highly increased in ApoE^-/^- mice models, compared with those of wild-type mice, and the ApoE^-/^- mice treated with TPL had decreased levels of total cholesterol and total triglyceride in plasma, which exhibited a dose-dependent reduction as the dose of TPL increased. Moreover, the effects of TPL on the production of inflammatory cytokines in macrophages were determined by ELISA. The results demonstrated that the macrophages from ApoE^-/^- mice produced high levels of the inflammatory cytokines tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and IL-8. However, following treatment with TPL doses of 25, 50 and 100 µg/kg, the cytokine levels were significantly decreased in a dose-dependent manner. Additionally, proteins associated with lipid metabolism were tested by western blotting. The results showed that the expression of anti-ATP-binding cassette transporter A1 in the macrophages of ApoE^-/^- mice was increased following treatment with TPL. However, the expression levels of LXRα were not markedly changed following treatment of the mice with different doses of TPL. These results suggest that TPL inhibited the progression of atherosclerosis not only by inhibiting the chronic inflammatory response, but also by regulating lipid metabolism, which may provide new insights useful in the clinical therapy of atherosclerosis.

Minnelide/Triptolide Impairs Mitochondrial Function by Regulating SIRT3 in P53-Dependent Manner in Non-Small Cell Lung Cancer

Minnelide/Triptolide (TL) has recently emerged as a potent anticancer drug in non-small cell lung cancer (NSCLC). However, the precise mechanism of its action remains ambiguous. In this study, we elucidated the molecular basis for TL-induced cell death in context to p53 status. Cell death was attributed to dysfunction of mitochondrial bioenergetics in p53-deficient cells, which was characterized by decreased mitochondrial respiration, steady-state ATP level and membrane potential, but augmented reactive oxygen species (ROS). Increased ROS production resulted in oxidative stress in TL-treated cells. This was exhibited by elevated nuclear levels of a redox-sensitive transcriptional factor, NF-E2-related factor-2 (NRF2), along with diminished cellular glutathione (GSH) content. We further demonstrated that in the absence of p53, TL blunted the expression of mitochondrial SIRT3 triggering increased acetylation of NDUAF9 and succinate dehydrogenase, components of complexes I and II of the electron transport chain (ETC). TL-mediated hyperacetylation of complexes I and II proteins and these complexes displayed decreased enzymatic activities. We also provide the evidence that P53 regulate steady-state level of SIRT3 through Proteasome-Pathway. Finally, forced overexpression of Sirt3, but not deacetylase-deficient mutant of Sirt3 (H243Y), restored the deleterious effect of TL on p53-deficient cells by rescuing mitochondrial bioenergetics. On contrary, Sirt3 deficiency in the background of wild-type p53 triggered TL-induced mitochondrial impairment that echoed TL effect in p53-deficeint cells. These findings illustrate a novel mechanism by which TL exerts its potent effects on mitochondrial function and ultimately the viability of NSCLC tumor.

Therapeutic effects of triptolide via the inhibition of IL-1β expression in a mouse model of ulcerative colitis

The present study aimed to investigate the effect of triptolide (TL) on ulcerative colitis (UC) and explore the potential association between the therapeutic effects of TL and IL-1β expression using a 4,4-dimethyl-4-silapentane-1-sulfonic acid (DSS)-induced mouse model to simulate human UC. A total of 70 BALB/c female mice were randomly allocated into seven equal groups: Group A, blank control; group B, normal saline injection; group C, propylene glycol injection; group D (TL1), 0.2 mg/kg TL; group E (TL2), 0.4 mg/kg TL; group F (TL3), 0.6 mg/kg TL; and group G, dexamethasone injection. Mice activity, diet and stool characteristics were recorded daily. Mice were sacrificed by cervical dislocation on day 8, and disease activity indices, colon tissue histological scores and colonic histopathological scores were subsequently calculated. Serum levels of IL-1β were evaluated by enzyme-linked immunosorbent assay, and IL-1β expression levels were examined by reverse transcription-quantitative polymerase chain reaction with colonic mucosa specimen at the gene level and western blot analysis at the protein level. The IL-1β mRNA and protein expression levels were significantly elevated in the normal saline injection and propylene glycol injection groups compared with the blank control group and (P<0.01). In TL (TL2 and TL3)- and dexamethasone-treated mice, IL-1β expression levels were significantly decreased, as compared with the normal saline and propylene glycol injection groups (P<0.05). No significant difference was detected between TL (TL2 and TL3) and dexamethasone treatments. The results of the present study indicated that IL-1β expression was upregulated in the UC mouse model, which may be associated with the development and progression of UC. Furthermore, TL inhibited IL-1β expression, suggesting that TL may be a novel therapeutic target for the treatment of UC.

Protective effects of leucine against lipopolysaccharide-induced inflammatory response in Labeo rohita fingerlings

The present study investigated the protective effects of leucine against lipopolysaccharide (LPS)-induced inflammatory responses in Labeo rohita (rohu) in vivo and in vitro. Primary hepatocytes, isolated from the hepatopancreas, were exposed to different concentrations of LPS for 24 h to induce an inflammatory response, and the protective effects of leucine against LPS-induced inflammation were studied. Finally, we investigated the efficiency of dietary leucine supplementation in attenuating an immune challenge induced by LPS in vivo. Exposure of cells to 10-25 μg mL(-1) of LPS for 24 h resulted in a significant production of nitric oxide and release of lactate dehydrogenase to the medium, whereas cell viability and protein content were reduced (p < 0.05). LPS exposure (10 μg mL(-1)) increased mRNA levels of the pro-inflammatory cytokines TNF-α, IL-1β and IL-8 in vitro (p < 0.05). However, pretreatment with leucine prevented the LPS-induced upregulation of TNF-α, IL-1β and IL-8 mRNAs by downregulating TLR4, MyD88, NF-κBp65, and MAPKp38 mRNA expression. Interestingly, mRNA expression of the anti-inflammatory cytokine, IL-10, which was increased by LPS treatment, was further enhanced (p < 0.05) by leucine pretreatment. The enhanced expression of IL-10 might inhibit the production of other pro-inflammatory cytokines. It was found that leucine pretreatment attenuated the excessive activation of LPS-induced TLR4-MyD88 signaling as manifested by lower level of TLR4, MyD88, MAPKp38, NF-κBp65 and increased level of IκB-α protein in leucine pre-treatment group. In vivo experiments demonstrated that leucine pre-supplementation could protect fish against LPS-induced inflammation through an attenuation of TLR4-MyD88 signaling pathway. Taken together, we propose that leucine pre-supplementation decreases LPS-induced immune damage in rohu by enhancing the expression of IL-10 and by regulating the TLR4-MyD88 signaling pathways.

Pharmacogenomics of Scopoletin in Tumor Cells

Drug resistance and the severe side effects of chemotherapy necessitate the development of novel anticancer drugs. Natural products are a valuable source for drug development. Scopoletin is a coumarin compound, which can be found in several Artemisia species and other plant genera. Microarray-based RNA expression profiling of the NCI cell line panel showed that cellular response of scopoletin did not correlate to the expression of ATP-binding cassette (ABC) transporters as classical drug resistance mechanisms (ABCB1, ABCB5, ABCC1, ABCG2). This was also true for the expression of the oncogene EGFR and the mutational status of the tumor suppressor gene, TP53. However, mutations in the RAS oncogenes and the slow proliferative activity in terms of cell doubling times significantly correlated with scopoletin resistance. COMPARE and hierarchical cluster analyses of transcriptome-wide mRNA expression resulted in a set of 40 genes, which all harbored binding motifs in their promoter sequences for the transcription factor, NF-κB, which is known to be associated with drug resistance. RAS mutations, slow proliferative activity, and NF-κB may hamper its effectiveness. By in silico molecular docking studies, we found that scopoletin bound to NF-κB and its regulator IκB. Scopoletin activated NF-κB in a SEAP-driven NF-κB reporter cell line, indicating that NF-κB might be a resistance factor for scopoletin. In conclusion, scopoletin might serve as lead compound for drug development because of its favorable activity against tumor cells with ABC-transporter expression, although NF-κB activation may be considered as resistance factor for this compound. Further investigations are warranted to explore the full therapeutic potential of this natural product.

Triptolide mitigates radiation-induced pulmonary fibrosis via inhibition of axis of alveolar macrophages-NOXes-ROS-myofibroblasts

PURPOSE

IR-induced pulmonary fibrosis is one of the most severe late complications of radiotherapy for lung cancer. It is urgently needed to discover a new drug for anti-IR lung fibrosis. Our previous studies have indicated that TPL exhibits both anti-IR lung fibrosis and anti-tumor activities. To reveal the mechanism of TPL on anti-IR lung fibrosis, alveolar macrophages (AMs) were examined for TPL effect on their axis of Nicotinamide adenine dinucleotide phosphate oxidase-reactive oxygen species (NOXes-ROS) and myofibroblast activation.

METHODS AND MATERIALS

The fibrosis-prone C57BL/6 mice were irradiated with 15 Gy on whole chest, then one day later, mice were treated without or with TPL (i.v. 0.25 mg/kg, qod for 1 month). The AMs were collected from bronchoalveolar lavage fluids and studied for the production of ROS and the levels of NOXes. The effect of AMs on myofibroblast activation as labeled with F4/80 or α-SMA (α-smooth muscle actin) were examined using flow cytometry, Western blotting, or immunohistochemical staining.

RESULTS

TPL effectively reduced the IR-induced lung fibrosis as evidenced by the less myofibroblasts, less collagen deposit and less ROS in the IR-lung tissues. We found that ROS which responsible for myofibroblasts activation was mainly from AMs and was NOX2 and NOX4 dependent. TPL significantly reduced the infiltrated AMs in IR-lung tissues, and in addition, down regulated the level of NOX2 and NOX4 in AMs both in vitro and in vivo. Furthermore, by inhibiting NOXes dependent ROS in AMs, TPL deprived AMs' paracrine activation of myofibroblasts.

CONCLUSIONS

Our work demonstrated that the anti-fibrotic effect of TPL on IR-induced pulmonary fibrosis was related to its inhibition on the axis of alveolar macrophages-NOXes-ROS-myofibroblasts.

Sex-Related Differences of Lipid Metabolism Induced by Triptolide: The Possible Role of the LXRα/SREBP-1 Signaling Pathway

Triptolide, a diterpenoid isolated from the plant Tripterygium wilfordii Hook. f., exerts a unique bioactive spectrum of anti-inflammatory and anticancer activities. However, triptolide's clinical applications are limited due to its severe toxicities. Fatty liver toxicity occurs in response to triptolide, and this toxic response significantly differs between males and females. This report investigated the pathogenesis underlying the sex-related differences in the dyslipidosis induced by triptolide in rats. Wistar rats were administered 0, 150, 300, or 450 μg triptolide/kg/day by gavage for 28 days. Ultrastructural examination revealed that more lipid droplets were present in female triptolide-treated rats than in male triptolide-treated rats. Furthermore, liver triglyceride, total bile acid and free fatty acid levels were significantly increased in female rats in the 300 and 450 μg/kg dose groups. The expression of liver X receptor α (LXRα) and its target genes, cholesterol 7α-hydroxylase (CYP7A1) and Sterol regulatory element-binding transcription factor 1(SREBP-1), increased following triptolide treatment in both male and female rats; however, the female rats were more sensitive to triptolide than the male rats. In addition, the expression of acetyl-CoA carboxylase 1(ACC1), a target gene of SREBP-1, increased in the female rats treated with 450 μg triptolide/kg/day, and ACC1 expression contributed to the sex-related differences in the triptolide-induced dysfunction of lipid metabolism. Our results demonstrate that the sex-related differences in LXR/SREBP-1-mediated regulation of gene expression in rats are responsible for the sex-related differences in lipid metabolism induced by triptolide, which likely underlie the sex-related differences in triptolide hepatotoxicity. This study will be important for predicting sex-related effects on the pharmacokinetics and toxicity of triptolide and for improving its safety.