A small-molecule degrader of TET3 as treatment for anorexia nervosa in an animal model.

Anorexia nervosa (AN) is a psychiatric illness with the highest mortality. Current treatment options have been limited to psychotherapy and nutritional support, with low efficacy and high relapse rates. Hypothalamic AgRP (agouti-related peptide) neurons that coexpress AGRP and neuropeptide Y (NPY) play a critical role in driving feeding while also modulating other complex behaviors. We have previously reported that genetic ablation of Tet3, which encodes a member of the TET family dioxygenases, specifically in AgRP neurons in mice, activates these neurons and increases the expression of AGRP, NPY, and the vesicular GABA transporter (VGAT), leading to hyperphagia and anxiolytic effects. Bobcat339 is a synthetic small molecule predicted to bind to the catalytic pockets of TET proteins. Here, we report that Bobcat339 is effective in mitigating AN and anxiety/depressive-like behaviors using a well-established mouse model of activity-based anorexia (ABA). We show that treating mice with Bobcat339 decreases TET3 expression in AgRP neurons and activates these neurons leading to increased feeding, decreased compulsive running, and diminished lethality in the ABA model. Mechanistically, Bobcat339 induces TET3 protein degradation while simultaneously stimulating the expression of AGRP, NPY, and VGAT in a TET3-dependent manner both in mouse and human neuronal cells, demonstrating a conserved, previously unsuspected mode of action of Bobcat339. Our findings suggest that Bobcat339 may potentially be a therapeutic for anorexia nervosa and stress-related disorders.

TET3 epigenetically controls feeding and stress response behaviors via AGRP neurons.

The TET family of dioxygenases promote DNA demethylation by oxidizing 5-methylcytosine to 5-hydroxymethylcytosine (5hmC). Hypothalamic agouti-related peptide-expressing (AGRP-expressing) neurons play an essential role in driving feeding, while also modulating nonfeeding behaviors. Besides AGRP, these neurons produce neuropeptide Y (NPY) and the neurotransmitter GABA, which act in concert to stimulate food intake and decrease energy expenditure. Notably, AGRP, NPY, and GABA can also elicit anxiolytic effects. Here, we report that in adult mouse AGRP neurons, CRISPR-mediated genetic ablation of Tet3, not previously known to be involved in central control of appetite and metabolism, induced hyperphagia, obesity, and diabetes, in addition to a reduction of stress-like behaviors. TET3 deficiency activated AGRP neurons, simultaneously upregulated the expression of Agrp, Npy, and the vesicular GABA transporter Slc32a1, and impeded leptin signaling. In particular, we uncovered a dynamic association of TET3 with the Agrp promoter in response to leptin signaling, which induced 5hmC modification that was associated with a chromatin-modifying complex leading to transcription inhibition, and this regulation occurred in both the mouse models and human cells. Our results unmasked TET3 as a critical central regulator of appetite and energy metabolism and revealed its unexpected dual role in the control of feeding and other complex behaviors through AGRP neurons.

Isosibiricin inhibits microglial activation by targeting the dopamine D1/D2 receptor-dependent NLRP3/caspase-1 inflammasome pathway.

Microglia-mediated neuroinflammation is a crucial risk factor for neurological disorders. Recently, dopamine receptors have been found to be involved in multiple immunopathological processes and considered as valuable therapeutic targets for inflammation-associated neurologic diseases. In this study we investigated the anti-neuroinflammation effect of isosibiricin, a natural coumarin compound isolated from medicinal plant Murraya exotica. We showed that isosibiricin (10-50 µM) dose-dependently inhibited lipopolysaccharide (LPS)-induced BV-2 microglia activation, evidenced by the decreased expression of inflammatory mediators, including nitrite oxide (NO), tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1ß (IL-1ß) and interleukin-18 (IL-18). By using transcriptomics coupled with bioinformatics analysis, we revealed that isosibiricin treatment mainly affect dopamine receptor signalling pathway. We further demonstrated that isosibiricin upregulated the expression of dopamine D1/2 receptors in LPS-treated BV-2 cells, resulting in inhibitory effect on nucleotide binding domain-like receptor protein 3 (NLRP3)/caspase-1 inflammasome pathway. Treatment with dopamine D1/2 receptor antagonists SCH 23390 (1 µM) or sultopride (1 µM) could reverse the inhibitory effects of isosibiricin on NLRP3 expression as well as the cleavages of caspase-1 and IL-1ß. Collectively, this study demonstrates a promising therapeutic strategy for neuroinflammation by targeting dopamine D1/2 receptors.

Anti-inflammatory and cytotoxic carbazole alkaloids from Murraya kwangsiensis.

Chemical investigation of the traditional Chinese medicine, Murraya kwangsiensis, led to the isolation of 16 undescribed biscarbazole alkaloids, kwangsines A-M, two undescribed natural products, (+/-)-bispyrayafoline C, and 19 known monomeric analogues. (±)-Bispyrayafoline C and (±)-kwangsines A-C are four pairs of biscarbazole atropisomers, and they were separated by chiral HPLC to obtain the optically pure compounds. The structures of the undescribed compounds were elucidated on the basis of HRESIMS and NMR data analysis. Their absolute configurations were assigned via comparison of the specific rotation, ECD exciton coupling method, as well as comparison of experimental and calculated ECD data. A compound showed significant inhibition on NO production in lipopolysaccharide-stimulated BV-2 microglial cells, and four compounds exhibited moderate cytotoxicities against HepG2 cells, with IC50 values less than 20 µM.

Anti-inflammatory Flavanones and Flavanols from the Roots of Pongamia pinnata.

A phytochemical study of the roots of Pongamia pinnata afforded 29 flavanones and flavanols, including 7 previously undescribed compounds. The structures of the isolated compounds were determined by 1D and 2D NMR and mass spectroscopy data. The absolute configurations of the compounds were assigned via analysis of the specific rotations and electronic circular dichroism spectra, application of Mosher's method, and by comparing the calculated and experimental electronic circular dichroism spectra. The isolates were evaluated for their inhibitory effects on nitric oxide production in lipopolysaccharide-stimulated BV-2 microglial cells. All of the isolated compounds exhibited inhibitory effects against nitric oxide production, and most of them showed obvious anti-inflammatory activities (IC50 < 20 µM), among which 26: was the most active compound with an IC50 of 9.6 µM.

Anti-inflammatory flavone and chalcone derivatives from the roots of Pongamia pinnata (L.) Pierre.

A phytochemical study on the roots of Pongamia pinnata (L.) Pierre yielded 52 flavonoids, including four previously undescribed flavone and four previously undescribed chalcone derivatives. The structures of the isolated compounds were determined on the basis of the 1D, 2D NMR, and mass spectroscopic data. The absolute configurations of the compounds were assigned via the specific rotation, Mosher's method, as well as the electronic circular dichroism (ECD) spectra. All the isolates were evaluated for their inhibitory effects on NO production in LPS-stimulated BV-2 microglial cells. Ten compounds showed significant inhibitory effects against NO production, comparable to the positive control, dexamethasone.

Pyrrolo[2,1-a]isoquinoline and pyrrole alkaloids from Sinomenium acutum.

Two pyrrolo[2,1-a]isoquinolines (1 and 2) and three pyrrole alkaloids (3-5), including three new ones, named sinopyrines A-C (1-3), were isolated from the 95% EtOH extract of the stems and rhizomes of Sinomenium acutum (Thumb.) Rehd. et Wils. The structures of the new compounds were elucidated on the basis of spectroscopic data. This is the first report of pyrrole-bearing natural compounds from the family Menispermaceae.

Rhodomollins A and B, two Diterpenoids with an Unprecedented Backbone from the Fruits of Rhododendron molle.

Two new grayanoids, rhodomollin A (1) and rhodomollin B (2), possessing an unprecedented D-homo grayanane carbon skeleton, were isolated from the fruits of Rhododendron molle. The structures of 1 and 2 were fully characterized using a combination of spectroscopic analyses and X-ray crystallography. Rhodomollin B (2) exhibited modest activity against influenza virus A/95-359, with an IC50 value of 19.24 µM.

Selective Activation of Nociceptor TRPV1 Channel and Reversal of Inflammatory Pain in Mice by a Novel Coumarin Derivative Muralatin L from Murraya alata.

Coumarin and its derivatives are fragrant natural compounds isolated from the genus Murraya that are flowering plants widely distributed in East Asia, Australia, and the Pacific Islands. Murraya plants have been widely used as medicinal herbs for relief of pain, such as headache, rheumatic pain, toothache, and snake bites. However, little is known about their analgesic components and the molecular mechanism underlying pain relief. Here, we report the bioassay-guided fractionation and identification of a novel coumarin derivative, named muralatin L, that can specifically activate the nociceptor transient receptor potential vanilloid 1 (TRPV1) channel and reverse the inflammatory pain in mice through channel desensitization. Muralatin L was identified from the active extract of Murraya alata against TRPV1 transiently expressed in HEK-293T cells in fluorescent calcium FlexStation assay. Activation of TRPV1 current by muralatin L and its selectivity were further confirmed by whole-cell patch clamp recordings of TRPV1-expressing HEK-293T cells and dorsal root ganglion neurons isolated from mice. Furthermore, muralatin L could reverse inflammatory pain induced by formalin and acetic acid in mice but not in TRPV1 knock-out mice. Taken together, our findings show that muralatin L specifically activates TRPV1 and reverses inflammatory pain, thus highlighting the potential of coumarin derivatives from Murraya plants for pharmaceutical and medicinal applications such as pain therapy.

Biological Activity and Chemical Constituents of Essential Oil and Extracts of Murraya microphylla.

Murraya microphylla is the most closely related species to M. koenigii (Curry tree). Inspired by the traditional effects of M koenigii, the antioxidant, anti- inflammatory, and cytotoxic activities of the essential oil and extracts of M. microphylla were evaluated for the first time. The light petroleum and chloroform extracts were found to be able to scavenge DPPH free radicals, inhibit linoleic acid peroxidation, and nitric oxide production, as well as to present cytotoxicity to the human cancer cell lines HepG2, Bel7402, Bel7403, and Hela, but the essential oil only showed moderate activities. Chemical analysis of the active extracts by LC-DAD-MS" indicated that carbazole alkaloids were the main constituents. GC-MS analysis of the essential oil resulted in identification of 91 constituents, representing 96.9% of the total oil, with (E)-caryophyllene (18.4%) and terpinen-4-ol (12.6%) as the major constituents. These results demonstrate that M microphylla has similar biological activities, as well as chemical constituents to M. koenigii, and the carbazole alkaloids were disclosed to be the main potential active components. A promising development as a flavor and potential therapeutic agent could thus be predicated for this plant.

Antinociceptive Grayanoids from the Roots of Rhododendron molle.

Nine new grayanoids (1-9), together with 11 known compounds, were isolated from the roots of Rhododendron molle. The structures of the new compounds (1-9) were determined on the basis of spectroscopic analysis, including HRESIMS, and 1D and 2D NMR data. Compounds 4, 6, 12, and 14-20 showed significant antinociceptive activities in an acetic acid-induced writhing test. In particular, 14 and 15 were found to be more potent than morphine for both acute and inflammatory pain models and 100-fold more potent than gabapentin in a diabetic neuropathic pain model.

Natural small molecule FMHM inhibits lipopolysaccharide-induced inflammatory response by promoting TRAF6 degradation via K48-linked polyubiquitination.

TNF receptor-associated factor 6 (TRAF6) is a key hub protein involved in Toll-like receptor-dependent inflammatory signaling pathway, and it recruits additional proteins to form multiprotein complexes capable of activating downstream NF-κB inflammatory signaling pathway. Ubiquitin-proteasome system (UPS) plays a crucial role in various protein degradations, such as TRAF6, leading to inhibitory effects on inflammatory response and immunologic function. However, whether ubiquitination-dependent TRAF6 degradation can be used as a novel anti-inflammatory drug target still remains to be explored. FMHM, a bioactive natural small molecule compound extracted from Chinese herbal medicine Radix Polygalae, suppressed acute inflammatory response by targeting ubiquitin protein and inducing UPS-dependent TRAF6 degradation mechanism. It was found that FMHM targeted ubiquitin protein via Lys48 site directly induced Lys48 residue-linked polyubiquitination. This promoted Lys48 residue-linked polyubiquitin chain formation on TRAF6, resulting in increased TRAF6 degradation via UPS and inactivation of downstream NF-κB inflammatory pathway. Consequently, FMHM down-regulated inflammatory mediator levels in circulation, protected multiple organs against inflammatory injury in vivo, and prolong the survival of endotoxemia mouse models. Therefore, FMHM can serve as a novel lead compound for the development of TRAF6 scavenging agent via ubiquitination-dependent mode, which represents a promising strategy for treating inflammatory diseases.

Nitrogen Oxide Inhibitory Trimeric and Dimeric Carbazole Alkaloids from Murraya tetramera.

Two new structurally unique trimeric carbazole alkaloids, murratrines A and B (1, 2), and 11 new carbazole dimers, murradines A-K (3-13), and four known analogues (14-17) were isolated from the leaves and stems of Murraya tetramera. The structures and relative configurations of 1-13 were elucidated on the basis of comprehensive 1D and 2D NMR spectroscopy, high-resolution mass spectrometry, and electronic circular dichroism (ECD) data analysis. Murratrines A and B (1, 2) both contain an unprecedented carbazole trimeric skeleton, and murradines A and D (3, 6) are the first natural C-1-C-3'-methyl-linked and C-6-C-3'-methyl-linked dimeric carbazole alkaloids, respectively. Compounds 4, 10, 14, 15, and 17 exhibited inhibition of nitric oxide production stimulated by lipopolysaccharide in BV-2 microglial cells with IC50 values in the range of 11.2-19.3 µM.

[Study on secondary metabolites of endophytic fungi Penicillium dangeardii].

Endophytic fungi Penicillium dangeardii, isolated from Lysidice rhodostegia Hance root, was fermented and the secondary metabolites were studied. By means of Sephadex LH-20 column chromatography, ODS column chromatography and PHPLC over the fermented culture, 5 compounds were isolated. By using ESI-MS and NMR, the structures of the compounds were determined as N-[9-(ß- D-ribofuranosyl)-9H-purin-6-yl]-L-aspartic acid (1), 3-caffeoylquinic acid (2), 4-caffeoylquinic acid (3), and 5-caffeoylquinic acid (4), 3-hydroxy-benzoic acid-4-O-ß-D-glucopyranoside (5).

[Simultaneous determination of benzophenones and xanthone in leaves of Aquilaria sinensis by RP-HPLC-UV].

This study is to develop a sensitive method by using reversed-phase high performance liquid chromatography coupled with UV detector (HPLC-UV) to simultaneously determine four bioactive compounds, iriflophenone 3-C-beta-D-glucoside, iriflophenone 3,5-C-beta-D-diglucoside, mangiferin, and iriflophenone 2-O-alpha-L-rhamnoside in the leaves of Aquilaria sinensis. An Agilent Zorbax SB-C, column (4, 6 mm x 250 mm, 5 microm) was used, and the gradient elution was performed with mobile phase of 0.1% aqueous phosphoric acid and acetonitrile at a flow rate of 1 mL x min(-1). The detection wavelength was 280 nm, and the column temperature was 25 degrees C. The four marker compounds were well separated with good linearity (R2 > 0.9990), precision, stability and repeatabili y. The-recovery rates were in the range of 98.80%-101.39%. For 15 branch of the leaves, the contents of iriflophenone 3-C-beta-D-gluoside, iriflophenone 3,5-C-beta-D-diglucoside, mangiferin, and iriflophenone 2-O-alpha-L-rhamnoside were between 0.41-14.48, 0.72-3.85, 4.30-29.07, 0.24-5.06 mg, respectivley. This method is precise, accurate and reliable, which provides an efficient way for the quality control of the leaves of A. sinensis. This will promote the comprehensive usage of this plant.

Anti-Neuroinflammatory Effect of MC13, a Novel Coumarin Compound From Condiment Murraya, Through Inhibiting Lipopolysaccharide-Induced TRAF6-TAK1-NF-κB, P38/ERK MAPKS and Jak2-Stat1/Stat3 Pathways.

MC13 is a novel coumarin compound found in Murraya, an economic crop whose leaves are widely used as condiment (curry) in cuisine. The aims of the present study were to investigate the neuroprotective effects of MC13 on microglia-mediated inflammatory injury model as well as potential molecular mechanism. Cell viability and apoptosis assay demonstrated that MC13 was not toxic to neurons and significantly protected neurons from microglia-mediated inflammatory injury upon lipopolysaccharide (LPS) stimulation. Results showed that MC13 markedly inhibited LPS-induced production of various inflammatory mediators, including nitrite oxide (Griess method), TNF-α and IL-6 (ELISA assay) in a concentration-dependent manner. Mechanism study showed that MC13 could suppress the activation of NF-κB, which was the central regulator for inflammatory response, and also decreased the interaction of TGF-ß-activated kinase 1 (TAK1)-binding protein (TAB2) with TAK1 and TNF receptor associated factor (TRAF6), leading to the decreased phosphorylation levels of NF-κB upstream regulators such as IκB and IκB kinase (IKK). MC13 also significantly down-regulated the phosphorylation levels of ERK and p38 MAPKs, which played key roles in microglia-mediated inflammatory response. Furthermore, MC13 inhibited Jak2-dependent Stat1/3 signaling pathway activation by blocking Jak2 phosphorylation, Stat1/3 phosphorylation, and nuclear translocation. Taken together, our results demonstrated that MC13 protected neurons from microglia-mediated neuroinflammatory injury by inhibiting TRAF6-TAK1-NF-κB, p38/ERK MAPKs, and Jak2-Stat1/3 pathways. Finally, MC13 might interact with LPS and interfere LPS-binding to cell membrane surface. These findings suggested that coumarin might act as a potential medicinal agent for treating neuroinflammation as well as inflammation-related neurodegenerative diseases.

Anti-inflammatory coumarin and benzocoumarin derivatives from Murraya alata.

Two new rare 8-methylbenzo[h]coumarins, muralatins A and B (1, 2), nine new C-8-substituted coumarins, muralatins C-K (3-11), and 22 known analogues (12-33) were isolated from the leaves of Murraya alata. The absolute configurations of compounds 5, 11, 23, 24, 27, 30, and 33 were assigned via comparison of their specific rotations, by Mosher's method, and by single-crystal X-ray diffraction and electronic circular dichroism (ECD) data of the in situ formed transition metal complexes. A putative biosynthesis pathway to 1 and 2 is proposed, and the chemical synthesis of 1 was accomplished through electrocyclization of 5,7-dimethoxy-8-[(Z)-3-methylbut-1,3-dienyl)]coumarin (12). Compounds 1, 2, 8, 12, and 31 showed inhibition of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages with IC50 values of 6.0-14.5 µM.

[Chemical constituents from roots of Illicium majus].

Ten compounds, including seven sesquiterpenes, two phenols and one phenylpropanoid, were isolated from the roots of Illicium majus by means of silica gel, ODS, Sephadex LH-20, and preparative HPLC. On analysis of MS and NMR spectroscopic data , their structures were established as cycloparviflorolide (1), cycloparvifloralone (2), tashironin (3), tashironin A (4), anislactone A(5), anislactone B (6), pseudomajucin (7), syringaldehyde (8), methyl-4-hydroxy-3, 5-dimethoxybenzoate (9), and (E)-3-methoxy-4,5-methylenedioxycinnamic alchol (10), respectively. Compounds 1-4 and 8-10 were first isolated from this plant. In the in vitro assays, at a concentration of 1.0 x 10(-5) mol x L(-1), compounds 5 and 6 were active against LPS induced NO production in microglia with a inhibition rate of 75.31% and 53.7%, respectively.

Comparative analysis of the essential oil composition of Murraya paniculata and M. exotica.

Murrayae Folium et Cacumen (MFC) is a traditional Chinese medicine (TCM) derived from the leaves and twigs of two aromatic species of Rutaceae: Murraya paniculata (L.) Jack and M. exotica L. It has long been used as a folk medicine in South China for the treatment of a variety of disorders, particularly for inflammatory lesions and pains. In the present study, a detailed chemical examination as well as a comparative analysis of the essential oil composition of M. paniculata and M. exotica was conducted by gas chromatography-mass spectrometry (GC-MS). A total of 141 volatile components were identified from the essential oil of these two plants. Sesquiterpenes were found to be the predominant constituents, accounting for 92.8% of the oil from M. paniculata and 87.9% of that from M. exotica. A comparative analysis of the essential oil composition of these two plants revealed a high level of similarity in their main constituents, such as the co-occurrence of E-caryophyllene, spathulenol and delta-elemene, which gave the chemical evidence for their equal medicinal application as MFC in TCMs. Moreover, in combination with literature reports, E-caryophyllene was theoretically deduced as one of the pharmacologically effective components of MFC that is responsible for treating inflammatory lesions and for local anaesthesia.

Diterpenoids and sesquiterpenoids from the roots of Illicium majus.

Five new diterpenoids (1-5), five new sesquiterpenoids (6-10), and three known compounds (11-13) were isolated from the roots of Illicium majus. Their structures were elucidated by extensive spectroscopic analysis. The absolute configuration of 1 was assigned by X-ray crystallography, whereas those of the 1,2-diol moieties in 3 and 4 were determined using Snatzke's method. The abietane acids 1, 2, 11, 12, and 13 displayed antiviral activity against the Coxsackie B3 virus, with IC50 values of 3.3-51.7 µM/mL.