Molecular mechanism of plant stress hormone methyl jasmonate for its anti-inflammatory activity

EZH2 activates Wnt/β-catenin signaling in human uterine fibroids, which is inhibited by the natural compound methyl jasmonate

OBJECTIVE

To investigate the link between EZH2 and Wnt/β-catenin signaling and its role in uterine fibroids (UFs) pathogenesis and explore the potential effect of natural compound methyl jasmonate (MJ) against UFs.

DESIGN

EZH2 overexpression or inhibition was achieved in human uterine leiomyoma (HuLM) cells using EZH2-expressing adenovirus or chemical EZH2 inhibitor (DZNep), respectively. The HuLM and normal uterine smooth muscle cells were treated with 0.1-3 mM of MJ, and several experiments were employed.

SETTING

Laboratory study.

PATIENTS(S)

None.

INTERVENTION(S)

Methyl jasmonate.

MAIN OUTCOME MEASURE(S)

Protein expression of EZH2, β-catenin, and proliferating cell nuclear antigen (PCNA) was measured by Western blot as well as gene expression alterations of Wnt ligands (Wnt5A, Wnt5b, and Wnt9A), WISP1, CTNNB1, and its responsive gene PITX2 using quantitative real-time polymerase chain reaction. The protein and ribonucleic acid (RNA) levels of several markers were measured in MJ-treated or untreated HuLM cells, including EZH2 and β-catenin, extracellular matrix markers collagen type 1 (COL1A1) and fibronectin (FN), proliferation markers cyclin D1 (CCND1) and PCNA, tumor suppressor marker p21, and apoptotic markers (BAX, cytochrome c, and cleaved caspase 3).

RESULT(S)

EZH2 overexpression significantly increased the gene expression of several Wnt ligands (PITX2, WISP1, WNT5A, WNT5B, and WNT9A), which increased nuclear translocation of β-catenin and PCNA and eventually HuLM cell proliferation. EZH2 inhibition blocked Wnt/β-catenin signaling activation where the aforementioned genes significantly decreased as well as PCNA, cyclin D1, and PITX2 protein expression compared with those in untreated HuLM. Methyl jasmonate showed a potent antiproliferative effect on HuLM cells in a dose- and time-dependent manner. Interestingly, the dose range (0.1-0.5 mM) showed a selective growth inhibitory effect on HuLM cells, not on normal uterine smooth muscle cells. Methyl jasmonate treatment at 0.5 mM for 24 hours significantly decreased both protein and RNA levels of EZH2, β-catenin, COL1A1, FN, CCND1, PCNA, WISP1, and PITX2 but increased the protein levels of p21, BAX, cytochrome, c and cleaved caspase 3 compared with untreated HuLM. Methyl jasmonate-treated cells exhibited down-regulation in the RNA expression of 36 genes, including CTNNB1, CCND1, Wnt5A, Wnt5B, and Wnt9A, and up-regulation in the expression of 34 genes, including Wnt antagonist genes WIF1, PRICKlE1, and DKK1 compared with control, confirming the quantitative real-time polymerase chain reaction results.

CONCLUSION(S)

Our studies provide a novel link between EZH2 and the Wnt/β-catenin signaling pathway in UFs. Targeting EZH2 with MJ interferes with the activation of wnt/β-catenin signaling in our model. Methyl jasmonate may offer a promising therapeutic option as a nonhormonal and cost-effective treatment against UFs with favorable clinical utility, pending proven safe and efficient in human clinical trials.

Neuroprotective effects of methyl jasmonate in male Wistar rats exposed to delayed acetic acid-induced ulcerative colitis: involvement of antioxidant status, GFAP, and IBA-1 immunoreactivities

Neurobehavioral deficits have been severally reported as a comorbid outcome in inflammatory bowel diseases (IBDs). This study evaluated neurological changes in the experimental model of IBDs, as well potential protective effects of methyl jasmonate (MJ). The study used the acetic acid model of colitis and thereafter delayed the healing process by the administration of indomethacin (Indo) (2 mg/kg, SC). Thirty male Wistar rats (120-160 g) were divided into 5 groups (n = 6). Control, Colitis, Colitis + Indo, MJ (50 mg/kg, IP) + Colitis and MJ + Colitis + Indo. Colitis was induced by intrarectal administration of 2 mL, 4% acetic acid. Neurobehavioral studies were carried out to assess memory function, depression, and anxiety on day 7 of post-colitis induction. Animals were thereafter sacrificed to collect the brain tissues for routine histology, immunoreactivity of GFAP and IBA-1, and biochemical assays. Neurobehavioral tests showed anxiety, depression, and memory deficits, especially in the Colitis + Indo group which were accompanied by increased IBA-1 and GFAP count. MJ reversed these effects and reduced GFAP count in the hippocampus and amygdala as well as IBA-1 count in the hippocampus, amygdala, and cortex. Histological observations of these areas showed no significant histopathological changes across all groups. GPx and CAT levels were significantly reduced, while MPO was significantly increased in colitis and Colitis+indo groups when compared with control, which was attenuated in groups administered with MJ. These findings tuggest that MJ possesses neuroprotective, anti-oxidant, and neuron-regeneration properties. Therefore, it could be considered as a potential treatment for behavioral deficits associated with ulcerative colitis.

Therapeutic Potential of Plant Oxylipins

For immobile plants, the main means of protection against adverse environmental factors is the biosynthesis of various secondary (specialized) metabolites. The extreme diversity and high biological activity of these metabolites determine the researchers' interest in plants as a source of therapeutic agents. Oxylipins, oxygenated derivatives of fatty acids, are particularly promising in this regard. Plant oxylipins, which are characterized by a diversity of chemical structures, can exert protective and therapeutic properties in animal cells. While the therapeutic potential of some classes of plant oxylipins, such as jasmonates and acetylenic oxylipins, has been analyzed thoroughly, other oxylipins are barely studied in this regard. Here, we present a comprehensive overview of the therapeutic potential of all major classes of plant oxylipins, including derivatives of acetylenic fatty acids, jasmonates, six- and nine-carbon aldehydes, oxy-, epoxy-, and hydroxy-derivatives of fatty acids, as well as spontaneously formed phytoprostanes and phytofurans. The presented analysis will provide an impetus for further research investigating the beneficial properties of these secondary metabolites and bringing them closer to practical applications.

Glyphosate-induced GhAG2 is involved in resistance to salt stress in cotton

KEY MESSAGE

The transcription of GhAG2 was strongly enhanced by glyphosate treatment. Overexpression of GhAG2 could improve plant tolerance to salt and salicylic acid stress. Although glyphosate has been widely used as an herbicide over the past decade owing to its high efficacy on weed controls and worldwide commercialization of glyphosate-resistant crops, little is known about the glyphosate-induced responses and transcriptional changes in cotton plants. Here, we report the identification of 26 differentially expressed genes after glyphosate treatment, among which, six highly up-regulated sequences share homology to cotton expressed sequence tags (ESTs) responsive to abiotic stresses. In addition, we cloned GhAG2, a gene whose transcription was strongly enhanced by glyphosate treatment and other abiotic stresses. Transgenic GhAG2 plants showed improved tolerance to salt, and salicylic acid (SA) stress. The results could open the door to exploring the function of the GhAG2 proteins, the glyphosate-induced transcriptional profiles, and the physiological biochemical responses in cotton and other crops. GhAG2 could also be used to improve salt stress tolerance through breeding and biotechnology in crops. Furthermore, these results could provide guidelines to develop a glyphosate-inducible system for controlled expression of targeted genes in plants.

A probe-free electrochemical immunosensor for methyl jasmonate based on a Cu-MOF–carboxylated graphene oxide platform

A probe-free electrochemical immunosensor for methyl jasmonate has been developed based on a Cu-MOF-carboxylated graphene oxide platform.

Genome-Wide Identification, Characterization and Expression Analysis of the JAZ Gene Family in Resistance to Gray Leaf Spots in Tomato

The plant disease resistance system involves a very complex regulatory network in which jasmonates play a key role in response to external biotic or abiotic stresses. As inhibitors of the jasmonic acid (JA) signaling pathway, JASMONATE ZIM domain (JAZ) proteins have been identified in many plant species, and their functions are gradually being clarified. In this study, 26 JAZ genes were identified in tomato. The physical and chemical properties, predicted subcellular localization, gene structure, cis-acting elements, and interspecies collinearity of 26 SlJAZ genes were subsequently analyzed. RNA-seq data combined with qRT-PCR analysis data showed that the expression of most SlJAZ genes were induced in response to Stemphylium lycopersici, methyl jasmonate (MeJA) and salicylic acid (SA). Tobacco rattle virus RNA2-based VIGS vector (TRV2)-SlJAZ25 plants were more resistant to tomato gray leaf spots than TRV2-00 plants. Therefore, we speculated that SlJAZ25 played a negative regulatory role in tomato resistance to gray leaf spots. Based on combining the results of previous studies and those of our experiments, we speculated that SlJAZ25 might be closely related to JA and SA hormone regulation. SlJAZ25 interacted with SlJAR1, SlCOI1, SlMYC2, and other resistance-related genes to form a regulatory network, and these genes played an important role in the regulation of tomato gray leaf spots. The subcellular localization results showed that the SlJAZ25 gene was located in the nucleus. Overall, this study is the first to identify and analyze JAZ family genes in tomato via bioinformatics approaches, clarifying the regulatory role of SlJAZ25 genes in tomato resistance to gray leaf spots and providing new ideas for improving plant disease resistance.

Activation of L-type calcium channels and attenuation of oxidative stress are involved in the improving effect of methyl jasmonate on learning and memory and its anxiolytic property in rats

The present study was designed to evaluate the effect of plant bioactive compound methyl jasmonate on learning and memory, anxiety-like behaviors, and brain oxidative stress in rats. It has been indicated that methyl jasmonate stimulates calcium-binding protein expression and increases intracellular calcium (Ca2+). Therefore, we investigated the potential role of L-type calcium channel on methyl jasmonate effects. The animals were intracerebroventriculary (i.c.v.) injected with different doses of methyl jasmonate (0.5, 2.5, and 5 µg/rat). L-type calcium channel blocker (nifedipine 5 µg/rat, i.c.v.) was injected 30 min before methyl jasmonate (5 µg/rat). Shuttle box apparatus was used to evaluate passive avoidance memory. Anxiety-like behaviors were assessed by open field and elevated plus maze tests. Lastly, oxidative stress-related indices were assessed in hippocampus and prefrontal cortex. The data showed that methyl jasmonate dose-dependently could improve passive avoidance learning and memory and reduce anxiogenic behaviors. The methyl jasmonate effects were significantly prevented by nifedipine. Furthermore, central microinjection of methyl jasmonate significantly decreased hydrogen peroxide concentration, and increased reactive oxygen species scavenger activity (catalase and peroxide enzymes) in rats' hippocampus as well as prefrontal cortex. Indeed, the results indicated that the beneficial effects of methyl jasmonate on learning and memory and anxiety might be partly associated with L-type calcium channel and partly on the inhibition of oxidant indices.

PepT1-knockout mice harbor a protective metabolome beneficial for intestinal wound healing

Genetic knockout (KO) of peptide transporter-1 (PepT1) protein is known to provide resistance to acute colitis and colitis-associated cancer (CAC) in mouse models. However, it was unclear which molecule(s) or pathway(s) formed the basis for these protective effects. Recently, we demonstrated that the PepT1^-/- microbiota is sufficient to protect against colitis and CAC. Given that PepT1 KO alters the gut microbiome and thereby changes the intestinal metabolites that are ultimately reflected in the feces, we investigated the fecal metabolites of our PepT1 KO mice. Using a liquid chromatography-mass spectrometry (LC-MS)-based untargeted-metabolomics technique, we found that the fecal metabolites were significantly different between the KO and normal wild-type (WT) mice. Among the altered fecal metabolites, tuberonic acid (TA) was sevenfold higher in KO mouse feces than in WT mouse feces. Accordingly, we studied whether the increased TA could direct an anti-inflammatory effect. Using in vitro models, we discovered that TA not only prevented lipopolysaccharide (LPS)-induced inflammation in macrophages but also improved the epithelial cell healing processes. Our results suggest that TA, and possibly other fecal metabolites, play a crucial role in the pathway(s) associated with the anticolitis effects of PepT1 KO.NEW & NOTEWORTHY Fecal metabolites were significantly different between the KO and normal wild-type (WT) mice. One fecal metabolite, tuberonic acid (TA), was sevenfold higher in KO mouse feces than in WT mouse feces. TA prevented lipopolysaccharide (LPS)-induced inflammation in macrophages and improved the epithelial cell healing process.

Anti-trichomonad activities of different compounds from foods, marine products, and medicinal plants: a review

Human trichomoniasis, caused by the pathogenic parasitic protozoan Trichomonas vaginalis, is the most common non-viral sexually transmitted disease that contributes to reproductive morbidity in affected women and possibly to prostate cancer in men. Tritrichomonas foetus strains cause the disease trichomoniasis in farm animals (cattle, bulls, pigs) and diarrhea in domestic animals (cats and dogs). Because some T. vaginalis strains have become resistant to the widely used drug metronidazole, there is a need to develop alternative treatments, based on safe natural products that have the potential to replace and/or enhance the activity of lower doses of metronidazole. To help meet this need, this overview collates and interprets worldwide reported studies on the efficacy of structurally different classes of food, marine, and medicinal plant extracts and some of their bioactive pure compounds against T. vaginalis and T. foetus in vitro and in infected mice and women. Active food extracts include potato peels and their glycoalkaloids α-chaconine and α-solanine, caffeic and chlorogenic acids, and quercetin; the tomato glycoalkaloid α-tomatine; theaflavin-rich black tea extracts and bioactive theaflavins; plant essential oils and their compounds (+)-α-bisabolol and eugenol; the grape skin compound resveratrol; the kidney bean lectin, marine extracts from algae, seaweeds, and fungi and compounds that are derived from fungi; medicinal extracts and about 30 isolated pure compounds. Also covered are the inactivation of drug-resistant T. vaginalis and T. foetus strains by sensitized light; anti-trichomonad effects in mice and women; beneficial effects of probiotics in women; and mechanisms that govern cell death. The summarized findings will hopefully stimulate additional research, including molecular-mechanism-guided inactivations and human clinical studies, that will help ameliorate adverse effects of pathogenic protozoa.

The Evolving Role of Natural Compounds in the Medical Treatment of Uterine Fibroids

Uterine fibroids (UFs) remain a significant health issue for many women, with a disproportionate impact on women of color, likely due to both genetic and environmental factors. The prevalence of UFs is estimated to be approximately 70% depending on population. UF-derived clinical symptoms include pelvic pain, excessive uterine bleeding, gastrointestinal and voiding problems, as well as impaired fertility. Nowadays numerous methods of UF treatment are available-from conservative treatment to invasive surgeries. Selecting an appropriate treatment option should be individualized and adjusted to the patient's expectations as much as possible. So far, the mainstay of treatment is surgery, but their negative impact of future fertility is clear. On the other hand, emerging new pharmaceutical options have significant adverse effects like liver function impairment, hot flashes, bone density loss, endometrial changes, and inability to attempt conception during treatment. Several natural compounds are found to help treat UFs and relieve their symptoms. In this review we summarize all the current available data about natural compounds that may be beneficial for patients with UFs, especially those who want to preserve their future fertility or have treatment while actively pursuing conception. Vitamin D, epigallocatechin gallate, berberine, curcumin, and others are being used as alternative UF treatments. Moreover, we propose the concept of using combined therapies of natural compounds on their own or combined with hormonal agents to manage UFs. There is a strong need for more human clinical trials involving these compounds before promoting widespread usage.