Research Progress on the Mechanism of the Antitumor Effects of Cannabidiol.

Cannabidiol (CBD), a non-psychoactive ingredient extracted from the hemp plant, has shown therapeutic effects in a variety of diseases, including anxiety, nervous system disorders, inflammation, and tumors. CBD can exert its antitumor effect by regulating the cell cycle, inducing tumor cell apoptosis and autophagy, and inhibiting tumor cell invasion, migration, and angiogenesis. This article reviews the proposed antitumor mechanisms of CBD, aiming to provide references for the clinical treatment of tumor diseases and the rational use of CBD.

Danshensu methyl ester attenuated LPS-induced acute lung injury by inhibiting TLR4/NF-κB pathway.

Acute Lung Injury (ALI) manifests as an acute exacerbation of pulmonary inflammation with high mortality. The potential application of Danshensu methyl ester (DME, synthesized in our lab) in ameliorating ALI has not been elucidated. Our results demonstrated that DME led to a remarkable reduction in lung injury. DME promoted a marked increase in antioxidant enzymes, like superoxide dismutase (SOD), and glutathione (GSH), accompanied by a substantial decrease in reactive oxygen species (ROS), myeloperoxidase (MPO), and malondialdehyde (MDA). Moreover, DME decreased the production of IL-1ß, TNF-α and IL-6, in vitro and in vivo. TLR4 and MyD88 expression is reduced in the DME-treated cells or tissues, which further leading to a decrease of p-p65 and p-IκBα. Meanwhile, DME effectively facilitated an elevation in cytoplasmic p65 expression. In summary, DME could ameliorate ALI by its antioxidant functionality and anti-inflammation effects through TLR4/NF-κB, which implied that DME may be a viable medicine for lung injury.

Dimethyl Bisphenolate Ameliorates Carbon Tetrachloride-Induced Liver Injury by Regulating Oxidative Stress-Related Genes.

Liver disease accounts for millions of deaths per year all over the world due to complications from cirrhosis and liver injury. In this study, a novel compound, dimethyl bisphenolate (DMB), was synthesized to investigate its role in ameliorating carbon tetrachloride (CCl4)-induced liver injury through the regulation of oxidative stress-related genes. The structure of DMB was confirmed based on its hydrogen spectrum and mass spectrometry. DMB significantly reduced the high levels of ALT, AST, DBIL, TBIL, ALP, and LDH in a dose-dependent manner in the sera of CCl4-treated rats. The protective effects of DMB on biochemical indicators were similar to those of silymarin. The ROS fluorescence intensity increased in CCl4-treated cells but significantly weakened in DMB-treated cells compared with the controls. DMB significantly increased the content of oxidative stress-related GSH, Nrf2, and GCLC dose-dependently but reduced MDA levels in CCl4-treated cells or the liver tissues of CCl4-treated rats. Moreover, DMB treatment decreased the expression levels of P53 and Bax but increased those of Bcl2. In summary, DMB demonstrated protective effects on CCl4-induced liver injury by regulating oxidative stress-related genes.

A novel mechanism of cannabidiol in suppressing ovarian cancer through LAIR-1 mediated mitochondrial dysfunction and apoptosis.

Cannabidiol (CBD) is a nonpsychoactive cannabinoid compound. It has been shown that CBD can inhibit the proliferation of ovarian cancer cells, but the underlying specific mechanism is unclear. We previously presented the first evidence for the expression of leukocyte-associated immunoglobulin-like receptor 1 (LAIR-1), a member of the immunosuppressive receptor family, in ovarian cancer cells. In the present study, we investigated the mechanism by which CBD inhibits the growth of SKOV3 and CAOV3 ovarian cancer cells, and we sought to understand the concurrent role of LAIR-1. In addition to inducing ovarian cancer cell cycle arrest and promoting cell apoptosis, CBD treatment significantly affected the expression of LAIR-1 and inhibited the PI3K/AKT/mTOR signaling axis and mitochondrial respiration in ovarian cancer cells. These changes were accompanied by an increase in ROS, loss of mitochondrial membrane potential, and suppression of mitochondrial respiration and aerobic glycolysis, thereby inducing abnormal or disturbed metabolism and reducing ATP production. A combined treatment with N-acetyl-l-cysteine and CBD indicated that a reduction in ROS production would restore PI3K/AKT/mTOR pathway signaling and ovarian cancer cell proliferation. We subsequently confirmed that the inhibitory effect of CBD on the PI3K/AKT/mTOR signal axis and mitochondrial bioenergy metabolism was attenuated by knockdown of LAIR-1. Our animal studies further support the in vivo anti-tumor activity of CBD and suggest its mechanism of action. In summary, the present findings confirm that CBD inhibits ovarian cancer cell growth by disrupting the LAIR-1-mediated interference with mitochondrial bioenergy metabolism and the PI3K/AKT/mTOR pathway. These results provide a new experimental basis for research into ovarian cancer treatment based on targeting LAIR-1 with CBD.

Corrigendum: Danshensu methyl ester enhances autophagy to attenuate pulmonary fibrosis by targeting lncIAPF-HuR complex.

[This corrects the article DOI: 10.3389/fphar.2022.1013098.].

Danshensu methyl ester enhances autophagy to attenuate pulmonary fibrosis by targeting lncIAPF-HuR complex.

Pulmonary fibrosis is an irreversible fibrotic process that has a high mortality rate and limited treatment options; thus, developing a novel therapeutic drug is critical. In this study, we synthesized danshensu methyl ester (DME) and explored its anti-pulmonary fibrotic ability on TGF-ß1-stimulated lung fibroblast in vitro and on bleomycin-induced pulmonary fibrosis in vivo. Results showed that DME decreased the expression of differentiation-related proteins, including fibroblast activation protein 1 (FAP1) and S100 calcium-binding protein A4 (S100A4), and fibrotic markers, such as a-SMA, vimentin, and collagen in vivo and in vitro. In addition, DME markedly repressed myofibroblast proliferation and migration. Mechanistically, chromatin immunoprecipitation-PCR, RNA immunoprecipitation, half-life, and other experiments revealed that DME inhibited activating transcription factor 3 expression via TGF-ß1 signal transduction leading to a decrease in lncIAPF transcription and stability. Moreover, DME blocked human antigen R (HuR) nucleocytoplasmic translocation and promoted its degradation via downregulating lncIAPF, which markedly decreased the expression of HuR target genes such as negative autophagic regulators (EZH2, STAT1, and FOXK1). Collectively, our results demonstrated that DME enhanced autophagy to attenuate pulmonary fibrosis via downregulating the lncIAPF-HuR-mediated autophagic axis and the lncIAPF-HuR complex can be the target for drug action.

Mechanism of SMND-309 against lung injury induced by chronic intermittent hypoxia.

INTRODUCTION: Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a common sleep disorder that causes severe physiological disturbance. Evidence showed that OSAHS is an important associated comorbidity that can affect the survival of patients with pulmonary fibrosis. Until now, the potential mechanisms by which OSAHS accelerates the progression of lung fibrosis remain unclear. By constructing a pathological model of chronic intermittent hypoxia (CIH), the present study aimed to explore the pathological progress and potential mechanism of lung injury caused by OSAHS. Meanwhile, SMND-309 was given for treatment to evaluate its potential therapeutic role in CIH-induced lung injury. METHODS: Mice were randomly divided into (C57BL/6 wild-type) WT+(room air) RA, WT + CIH, SMND-309 + RA, and SMND-309 + CIH groups. The WT + CIH and SMND-309 + CIH groups were exposed to CIH condition for 12 weeks, while the other groups were processed in normal oxygen at the same time. The SMND-309 + RA and SMND-309 + CIH groups were intraperitoneally injected with SMND-309 at the last week of the modeling period. After 12 weeks of treatment, three mice from each group were perfused through the heart. Lung tissues were isolated, fixed, sectioned, and stained with H&E, Masson, and immunofluorescence stain. The rest of the lung tissues were harvested for Western blot and ELISA assays. RESULTS: CIH treatment increased the expression of pro-inflammatory factors (TNF-α and IL-6), resulting in lung tissue structure disorder, inflammatory cell infiltration, increased pulmonary capillary permeability, and pulmonary edema. The activation of the NF-κB signaling pathway played a crucial role in the process of inflammation. Noticeably, we observed M2 macrophage accumulation in the lung after CIH exposure, which promoted epithelial-mesenchymal transition (EMT) and pulmonary tissue fibrosis. ELISA assays showed the increased expression of TGF-ß, IL-10, and IL-4 in the CIH group. SMND-309 inhibited pulmonary inflammation, reduced the accumulation of M2 macrophage, alleviated collagen deposition andlung damage. CONCLUSION: CIH could induce chronic lung inflammation, promote the activation of M2 macrophages, trigger the occurrence of EMT, and accelerate the deposition of lung collagen, eventually leading to lung tissue damage. This study presents a possible explanation by which interstitial lung diseases, particularly idiopathic pulmonary fibrosis (IPF) with OSAHS, are usually associated with fast progress and poor prognosis. SMND-309 showed a good protective effect on CIH-induced lung damage.

Abnormal lipid droplets accumulation induced cognitive deficits in obstructive sleep apnea syndrome mice via JNK/SREBP/ACC pathway but not through PDP1/PDC pathway.

The mechanisms of chronic intermittent hypoxia (CIH)-induced cognitive deficits remain unclear. Here, our study found that about 3 months CIH treatment induced lipid droplets (LDs) accumulation in hippocampal nerve and glia cells of C57BL/6 mice, and caused severe neuro damage including neuron lesions, neuroblast (NB) apoptosis and abnormal glial activation. Studies have shown that the neuronal metabolism disorders might contribute to the CIH induced-hippocampal impairment. Mechanistically, the results showed that pyruvate dehydrogenase complex E1ɑ subunit (PDHA1) and the pyruvate dehydrogenase complex (PDC) activator pyruvate dehydrogenase phosphatase 1 (PDP1) did not noticeable change after intermittent hypoxia. Consistent with those results, the level of Acetyl-CoA in hippocampus did not significantly change after CIH exposure. Interestingly, we found that CIH produced large quantities of ROS, which activated the JNK/SREBP/ACC pathway in nerve and glia cells. ACC catalyzed the carboxylation of Acetyl-CoA to malonyl-CoA and then more lipid acids were synthesized, which finally caused aberrant LDs accumulation. Therefore, the JNK/SREBP/ACC pathway played a crucial role in the cognitive deficits caused by LDs accumulation after CIH exposure. Additionally, LDs were peroxidized by the high level of ROS under CIH conditions. Together, lipid metabolic disorders contributed to nerve and glia cells damage, which ultimately caused behavioral dysfunction. An active component of Salvia miltiorrhiza, SMND-309, dramatically alleviated these injuries and improved cognitive deficits of CIH mice.

Acetyl oxygen benzoate engeletin ester promotes KLF4 degradation leading to the attenuation of pulmonary fibrosis via inhibiting TGFß1-smad/p38MAPK-lnc865/lnc556-miR-29b-2-5p-STAT3 signal pathway.

Pulmonary fibrosis is a common pulmonary interstitial disease of pathogenesis without effective drugs for treatment. Therefore, discovering new and effective drugs is urgently needed. In the present study, we prepared a novel compound named acetyl oxygen benzoate engeletin ester (AOBEE), investigated its effect on experimental pulmonary fibrosis, and proposed a long non-coding RNA (lncRNA)-mediated mechanism of its action. Bleomycin-induced pulmonary fibrosis in mice exhibited that AOBEE improved forced vital capacity (FVC) and alveolar structure and inhibited α-SMA, vimentin, and collagen expression. TGFß1-stimulated fibroblast L929 cells showed that AOBEE reduced these fibrotic proteins expression and inhibited the activated-fibroblast proliferation and migration. Whole transcriptome sequencing was performed to screen out lncRNA-lnc865 and lnc556 with high expression under bleomycin treatment, but AOBEE caused a considerable decrease in lnc865 and lnc556. Mechanistic study elucidated that AOBEE alleviated pulmonary fibrosis through lnc865- and lnc556-mediated mechanism, in which both lnc865 and lnc556 sponged miR-29b-2-5p to target signal transducer and activator of transcription 3 (STAT3). Further signal pathway inhibitors and the Cignal Finder 45-pathway reporter array illustrated that the up- and downstream pathways were TGFß1-smad2/3 and p38MAPK, and Krüppel-like factor 4 (KLF4), respectively. In conclusion, AOBEE promoted KLF4 degradation leading to the attenuation of pulmonary fibrosis by inhibiting TGFß1-smad/p38MAPK-lnc865/lnc556-miR-29b-2-5p-STAT3 signal pathway. We hope this work will provide valuable information to design new drugs and therapeutic targets of lncRNAs for pulmonary fibrosis treatment.

LAIR-1 suppresses cell growth of ovarian cancer cell via the PI3K-AKT-mTOR pathway.

Recently, over-expression of LAIR-1 has been found in some solid cancers, including ovarian cancer. The role of LAIR-1 in cancer progression needs further investigation. In this study, we identified the LAIR-1 cDNA sequence of the ovarian cancer cells HO8910. Using SKOV3 cells, we confirmed the finding from our previous study that LAIR-1 could suppress in vitro cell proliferation and cell migration. We also found LAIR-1 overexpression can induce apoptosis of SKOV3 cells. We revealed LAIR-1 suppressed cell growth by inhibiting the PI3K-AKT-mTOR axis. Moreover, the LAIR-1 antitumor activity and its mechanism were also identified in vivo. We used Co-IP assay and mass spectrometry to identify potential LAIR-1-binding proteins in LAIR-1 overexpressing SKOV3 cells. MS analysis identified 167 potentially interacting proteins. GO analyses indicated a possible involvement of LAIR-1 in mRNA processing through its interaction with some eukaryotic translation initiation factors (eIF4E1B, eIF2S3, eIF3D, eIF4G2, eIF5B) and eukaryotic translation elongation factors (eEF1A2 and eEF1B2). Our findings suggest that LAIR-1 may suppress the growth of ovarian cancer cells by serving as a modulator that suppresses PI3K-AKT-mTOR directly or regulating protein synthesis at the translational level. Our results indicate that a LAIR-1-based strategy may prevent or suppress the progression of ovarian cancer.

Niclosamide inhibits ovarian carcinoma growth by interrupting cellular bioenergetics.

Background: Ovarian carcinoma is a common malignant tumor of the female reproductive organs with an incidence rate second only to cervical and endometrial cancers. In the past 10 years, anticancer therapy has focused on Niclosamide, an anthelmintic teniacide that is commonly used against tapeworms and has been approved for use in humans for nearly 50 years. Importantly, Niclosamide has been confirmed to target the Wnt/ß-catenin, mTOR, STAT3, NF-κB, and Notch pathways has been widely investigated in multiple cancer types. However, the potential benefits of Niclosamide therapy for treatment of ovarian carcinoma have not been established. Methods: CCK-8 colony formation assays were performed to evaluate cell viability and tumor growth. Cell apoptosis was measured by flow cytometry. A Seahorse XF96 analyzer was used to measure cellular bioenergetics. Mito-tracker stained mitochondria were visualized by confocal microscopy. Western blotting was used to detect expressed proteins. A nude mouse transplanted-tumor model was used to evaluate the antitumor activity of Niclosamide in ovarian carcinoma. Result: Niclosamide treatment significantly suppressed ovarian carcinoma growth and induced cell apoptosis by inactivating MEK1/2-ERK1/2 mediated signal transduction. Overall, mitochondrial respiration and aerobic glycolysis were both decreased by Niclosamide treatment. Niclosamide dramatically enhanced ROS-activated and JNK-mediated apoptosis in cells subjected to glucose deprivation. Niclosamide also showed in vivo antitumor activity in the nude mouse transplanted-tumor model. Conclusion: Collectively, these data highlight a novel anti-tumor mechanism of Niclosamide that involves an interruption of cell metabolism. The finding also indicates a potential for the application of Niclosamide in ovarian carcinoma therapy.

Cannabidiol Induces Cell Cycle Arrest and Cell Apoptosis in Human Gastric Cancer SGC-7901 Cells.

The main chemical component of cannabis, cannabidiol (CBD), has been shown to have antitumor properties. The present study examined the in vitro effects of CBD on human gastric cancer SGC-7901 cells. We found that CBD significantly inhibited the proliferation and colony formation of SGC-7901 cells. Further investigation showed that CBD significantly upregulated ataxia telangiectasia-mutated gene (ATM) and p53 protein expression and downregulated p21 protein expression in SGC-7901 cells, which subsequently inhibited the levels of CDK2 and cyclin E, thereby resulting in cell cycle arrest at the G0-G1 phase. In addition, CBD significantly increased Bax expression levels, decreased Bcl-2 expression levels and mitochondrial membrane potential, and then upregulated the levels of cleaved caspase-3 and cleaved caspase-9, thereby inducing apoptosis in SGC-7901 cells. Finally, we found that intracellular reactive oxygen species (ROS) increased after CBD treatment. These results indicated that CBD could induce G0-G1 phase cell cycle arrest and apoptosis by increasing ROS production, leading to the inhibition of SGC-7901 cell proliferation, thereby suggesting that CBD may have therapeutic effects on gastric cancer.

Novel formononetin-7-sal ester ameliorates pulmonary fibrosis via MEF2c signaling pathway.

Pulmonary fibrosis is a progressive disorder with poor prognosis and limited treatment options. Therefore, novel therapeutic drugs should be developed in preclinical studies. In this study, we designed and synthesized a novel compound named formononetin-7-sal ester (FS). We also investigated its anti-pulmonary fibrosis ability on transforming growth factor beta 1 (TGF-ß1)-stimulated pulmonary epithelial cells and fibroblasts in vitro and on bleomycin (BLM)-induced pulmonary fibrosis in vivo. FS strongly blocked cell proliferation and migration, which were activated by TGF-ß1, thereby reducing the expression of lung fibrosis markers, such as vimentin, alpha-smooth muscle actin (α-SMA), Snail, and collagen I and III, and increasing the expression of the epithelial cell marker E-cadherin. FS ameliorated BLM-induced pulmonary fibrosis in mice and decreased histopathologic fibrosis scores and collagen deposition. A low expression of hydroxyproline, vimentin, α-SMA, and Snail and a high expression of E-cadherin were found in FS-treated lungs compared with BLM-instilled lungs. Using the Cignal Finder 45-Pathway Reporter Array, we tested the regulation of FS in pulmonary fibrosis-associated signaling pathways and observed that FS significantly inhibited the myocyte enhancer factor-2c (MEF2c) signaling pathway. Gain- and loss-of-function studies, rescue experiments and promoter activity testing were designed to further confirm this result in vivo and in vitro. Collectively, our results demonstrated that FS prevents pulmonary fibrosis via the MEF2c signaling pathway.

Five ETS family members, ELF-1, ETV-4, ETV-3L, ETS-1, and ETS-2 upregulate human leukocyte-associated immunoglobulin-like receptor-1 gene basic promoter activity.

Human leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1), an immunoinhibitory receptor, is expressed on most types of hematopoietic cells and some tumor cells. LAIR-1 plays an inhibitory role in immune cell maturation, differentiation, and activation. LAIR-1 is also involved in some autoimmune diseases and tumors. However, the mechanism controlling the regulation of the LAIR-1 gene is still unknown. In order to elucidate the molecular mechanisms involved in LAIR-1 regulation, in the present study, we cloned and characterized the promoter region of LAIR-1 gene using a series of truncated promoter plasmids in luciferase reporter assays. Our results show that the basic core promoter of LAIR-1 is located within the region -256/-8 relative to the translational start site. Our further studies indicate that five ETS transcription factors: ELF-1, ETV-4, ETV-3L, ETS-1 and ETS-2, can up-regulate the LAIR-1 basic promoter activity. Of these, ETS-2 is the most effective transcription factor. Moreover, ETS-2 was confirmed to interact directly with the basic promoter of LAIR-1. This study presents the first description of regions/factors capable of up-regulation the promoter activity of LAIR-1. This new knowledge contributes to understanding of the molecular mechanisms involved in LAIR-1 associated immune regulation and diseases.

Leucine-derived cyanoglucosides from the aerial parts of Sorbaria sorbifolia (L.) A. Braun.

Six new cyanoglucosides, 2S-cardiospermin-5-benzoate (1), 2R-cardiospermin-5-p-hydroxybenzoate (2), 2S-cardiospermin-5-cis-p-coumarate (3), isocardiospermin-5-p-hydroxybenzoate (4), sutherlandin-5-p-hydroxybenzoate (5), and sutherlandin-5-cis-p-coumarate (6), together with 17 known compounds were isolated from Sorbaria sorbifolia. The structures of the new compounds were elucidated by extensive spectroscopic methods, including 1D and 2D NMR, HR-ESI-MS and ECD experiments. The biosynthetic relationship of 1-9 was also discussed. The cyanoglucosides (1-9) and 15 exhibited moderate inhibitory effect on nitric oxide production of RAW264.7 macrophages stimulated by lipopolysaccharide (LPS).

Grisemycin, a Bridged Angucyclinone with a Methylsulfinyl Moiety from a Marine-Derived Streptomyces sp.

Grisemycin (1), the first sulfur angucyclinone with an unusual ether-bridged system, was isolated from a marine-derived Streptomyces griseus strain M268. Its novel, here cage-like, structure was determined by spectroscopic analysis and single-crystal X-ray diffraction. Compound 1 exhibited modestly selective activity against the HL-60 cell line with an IC50 value of 31.54 µM. Futhermore, the absolute stereochemistry of kiamycin (2), an 1,12-epoxybenz[a]anthracene, previously obtained from the same strain, was established by X-ray diffraction analysis.

[Chemical constituents contained in Salvia castanea].

OBJECTIVE: To investigate chemical constituents contained in Salvia castanea. METHOD: The compounds were separated and purified by silica gel, macroporous resin, RP-C18 and Sephadex LH-20 column chromatography. The structures were identified on the basis of physicochemical property and spectral data. RESULT: Nineteen compounds were separated and identified as tanshinone II(A) (1) , tanshinone II(B) (2), hydroxytanshinone II(A) (3), tanshinone I(4), dihydrotanshinone I(5), cryptotanshinone (6) , neotanshinone A(7) , neotanshinone B(8) , tanshinoldehyde(9), przewaquinone A(10), przewaquinone B(11), sugiol(12), caffeic acid(13), rosmarinci acid(14), ethylrosmarinate(15), lithospermic acid(16), pro-lithospermic acid ( 17) , protocatechualdehyde (18), and danshensu(19). CONCLUSION: Compounds 2, 3, 7-13 and 15-19 were separated from S. castanea for the first time.

New abietane norditerpenoid from Salvia miltiorrhiza with cytotoxic activities.

One new abietane-type norditerpenoid, named militibetin A (1), was isolated from the dry roots of Salvia miltiorrhiza, along with two known diterpenoids, yunnannin A (2) and ferruginol (3). Their structures were established by means of extensive spectroscopic analyses. In vitro, compounds 1-3 were found to show cytotoxicities against selected cancer cells, including P-388, HONE-1, and HT-29, and gave ED(50) values in the range of 2.9-5.4 µg ml(- 1).

Two new C13-norisoprenoids from Solanum lyratum.

Two new C(13)-norisoprenoids, named lyratols E and F (1-2), were isolated from the whole plant of Solanum lyratum Thunb, and their structures were elucidated by extensive spectroscopic analyses. In vitro, two new compounds were found to show significant cytotoxicity against selected cancer cells including P-388 and HT-29.

Two new cytotoxic ent-clerodane diterpenoids from Scutellaria barbata.

Two new ent-clerodane diterpenoids have been isolated from Scutellaria barbata, and their structures were established by detailed spectroscopic analyses as (13R)-6α,7ß-dihydroxy-8ß,13-epoxy-11ß-nicotinyloxy-ent-clerodan-3-en-15,16-olide (scutelinquanine D, 1) and (11E)-6α-acetoxy-7ß,8ß-dihydroxy-ent-clerodan-3,11,13-trien-15,16-olide (6-acetoxybarbatin C, 2). In vitro, the isolated two new compounds showed significant cytotoxic activities against three human cancer cell lines (HONE-1 nasopharyngeal, KB oral epidermoid carcinoma, and HT29 colorectal carcinoma cells), and gave IC(50) values in the range of 2.5-6.6 µM.