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1.
J Pharmacol Exp Ther ; 388(1): 156-170, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-37918855

RESUMEN

Spleen tyrosine kinase (Syk) is an intracellular tyrosine kinase involved in the signal transduction in immune cells mainly. Its aberrant regulation is associated with diversified allergic disorders, autoimmune diseases and B cell malignancies. Therefore, inhibition of Syk is considered a reasonable approach to treat autoimmune/inflammatory diseases and B cell malignancies. Here we described the preclinical characterization of sovleplenib, a novel, highly potent and selective, oral Syk inhibitor, in several rodent autoimmune disease models. Sovleplenib potently inhibited Syk activity in a recombinant enzymatic assay and Syk-dependent cellular functions in various immune cell lines and human whole blood in vitro. Furthermore, sovleplenib, by oral administration, demonstrated strong in vivo efficacies in murine models of immune thrombocytopenia (ITP), autoimmune hemolytic anemia (AIHA), and chronic graft-versus-host disease (cGVHD), and a rat model of collagen induced arthritis (CIA) respectively, in a dose-dependent manner. Collectively, these results clearly supported sovleplenib as a therapeutic agent in the treatment of autoimmune diseases. Sovleplenib is being globally developed for ITP (Phase III, NCT05029635, Phase Ib/II, NCT03951623), wAIHA (Phase II/III, NCT05535933) and B-cell lymphoma (Phase I, NCT02857998, NCT03779113). SIGNIFICANCE STATEMENT: Syk is a key mediator of signaling pathways downstream of a wide array of receptors important for immune functions, including the B cell receptor, immunoglobulin receptors bearing Fc receptors. Inhibition of Syk could provide a novel therapeutic approach for autoimmune diseases and hematologic malignancies. The manuscript describes the preclinical pharmacology characterization of sovleplenib, a novel Syk inhibitor, in enzymatic and cellular assays in vitro and several murine autoimmune disease models in vivo.


Asunto(s)
Enfermedades Autoinmunes , Neoplasias , Ratas , Ratones , Humanos , Animales , Proteínas Tirosina Quinasas , Quinasa Syk , Transducción de Señal , Inhibidores de Proteínas Quinasas/farmacología , Enfermedades Autoinmunes/tratamiento farmacológico , Neoplasias/tratamiento farmacológico
2.
Org Biomol Chem ; 18(6): 1046-1056, 2020 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-31971201

RESUMEN

The fascinating structure of Strychnos alkaloids has evoked immense synthetic interest from the chemical community since the landmark synthesis of strychnine by Woodward. After that, the pursuit of the total synthesis of Strychnos alkaloids has never stopped. In this context, the synthesis of strychnine has become a benchmark for the evaluation of new synthetic strategies. Furthermore, the characteristic structure of these alkaloids has also served as an inspiration for the development of novel synthetic methodologies, which provide new synthetic strategies for the synthesis of Strychnos alkaloids. In this article, the recent progress in the total synthesis of Strychnos alkaloids since 2011 is reviewed, including successful total syntheses and synthetic efforts toward Strychnos alkaloids. According to the key feature employed in the synthesis, the content was categorized into novel synthetic methodologies and innovative strategies based on well-documented methodologies.


Asunto(s)
Alcaloides/síntesis química , Strychnos/química , Alcaloides/química , Conformación Molecular
3.
Mediators Inflamm ; 2020: 8528901, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33100904

RESUMEN

Mycobacterium tuberculosis (Mtb) remains a great threat to global health, killing more people than any other single infectious agent and causing uncontrollable inflammation in the host. Poorly controlled inflammatory processes can be deleterious and result in immune exhaustion. The current tuberculosis (TB) control is facing the challenge of drugs deficiency, especially in the context of increasingly multidrug resistant (MDR) TB. Under this circumstance, alternative host-directed therapy (HDT) emerges timely which can be exploited to improve the efficacy of TB treatment and disease prognosis by targeting the host. Here, we established the in vitro infection model of Mtb macrophages with H37Ra strain to seek effective anti-TB active agent. The present study showed that Guttiferone K, isolated from Garcinia yunnanensis, could significantly inhibit Mtb-induced inflammation in RAW264.7 and primary peritoneal macrophages. It was evidenced by the decreased production of inflammatory mediators, including interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). Further studies with immunoblotting and immunofluorescence revealed that Guttiferone K obviously inhibits the nuclear factor-kappa B (NF-κB) both in RAW264.7 and primary peritoneal macrophages relying on the TLR/IRAK-1 pathway. Guttiferone K could also suppress the NLRP3 inflammasome activity and induce autophagy by inhibiting the protein kinase B (p-Akt) and mammalian target of rapamycin (mTOR) phosphorylation at Ser473 and Ser2448 in both cell lines. Thus, Guttiferone K possesses significant anti-inflammatory effect, alleviating Mtb-induced inflammation with an underlying mechanism that targeting on the TLR/IRAK-1 pathway and inhibiting the downstream NF-κB and Akt/mTOR signaling pathways. Together, Guttiferone K can be an anti-inflammatory agent candidate for the design of new adjunct HDT drugs fighting against tuberculosis.


Asunto(s)
Antiinflamatorios/uso terapéutico , Benzofenonas/uso terapéutico , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/patogenicidad , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Western Blotting , Supervivencia Celular/efectos de los fármacos , Femenino , Inmunoprecipitación , Ratones , Células RAW 264.7
4.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(1): 65-67, 2020 Jan 08.
Artículo en Zh | MEDLINE | ID: mdl-32343070

RESUMEN

From the point of view of medical device registration technical evaluation, production process of endoscope, three-dimensional imaging(3D), high resolution imaging are discussed. We focus on the process of design and development, especially verification and validation. The general principle is that all risks and unexpected impacts should be minimized and acceptable to ensure that benefits are greater than risks in normal use.


Asunto(s)
Endoscopios , Diseño de Equipo , Imagenología Tridimensional
5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(5): 443-447, 2020 Oct 08.
Artículo en Zh | MEDLINE | ID: mdl-33047571

RESUMEN

At present, the most commonly used sterilization method for medical devices is ethylene oxide sterilization. The residue after sterilization is closely related to the health of the people who contacted with the medical devices. The study team analyzed the possible residues of medical devices after sterilization with ethyleneoxide. It is suggested that ethylene oxide, 2-chloroethanol and ethylene glycol should be evaluated comprehensively through the analysis of factors such as production links of medical devices, production process of ethylene oxide, sterilization process, sterilization environment and detection method.


Asunto(s)
Equipos y Suministros , Óxido de Etileno , Esterilización , Humanos
6.
Angew Chem Int Ed Engl ; 58(19): 6400-6404, 2019 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-30815962

RESUMEN

An efficient and divergent approach toward the synthesis of all four de-O-sulfonated sulfonium type α-glucosidase inhibitors, originally isolated from plants of genus Salacia, is reported for the first time. The key strategy features a coupling reaction between thiol derivatives and a diiodide counterpart. The newly designed thiol coupling partner presents high chemical stability, while the diiodide partner could be easily obtained with increased overall yields compared with conventional routes. The intermolecular nucleophilic substitution reaction followed by a diastereoselective intramolecular cyclization provided the target five-member sulfonium salt structure, which was connected in an α-orientation to a polyhydroxylated side-chain moiety.

7.
Angew Chem Int Ed Engl ; 57(14): 3806-3809, 2018 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-29418057

RESUMEN

A highly enantioselective tandem Michael addition of tryptamine-derived oxindoles to alkynones was developed by taking advantage of a chiral N,N'-dioxide Sc(OTf)3 catalyst. The reaction enables the facile preparation of enantioenriched spiro[pyrrolidine-3,3'-oxindole] compounds, which provides a novel strategy for the synthesis of monoterpenoid indole alkaloids. As a demonstration, the asymmetric synthesis of strychnos alkaloids [(-)-tubifoline, (-)-tubifolidine, (-)-dehydrotubifoline] was achieved in 10-11 steps.

8.
Zhongguo Yi Liao Qi Xie Za Zhi ; 42(5): 372-374, 2018 Sep 30.
Artículo en Zh | MEDLINE | ID: mdl-30358355

RESUMEN

In this paper,standards for active implantable cardiac medical devices are discussed.Potential EMC risks and its correspondent tests settings as well as the design principle of the tests have been analyzed.The problems arises from the difference between domestic and international standards on the limitation of exposure of the general public to electromagnetic fields and the lack of assessment of EMC risk which generated by the the 5th generation mobile communication for the impact on the active implantable devices devices.


Asunto(s)
Campos Electromagnéticos , Corazón Auxiliar , Prótesis e Implantes , Estándares de Referencia
10.
Mediators Inflamm ; 2017: 2432904, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28642632

RESUMEN

Mycobacterium tuberculosis (Mtb) remains a significant menace to global health as it induces granulomatous lung lesions and systemic inflammatory responses during active tuberculosis (TB). Micheliolide (MCL), a sesquiterpene lactone, was recently reported to have a function of relieving LPS-induced inflammatory response, but the regulative role of MCL on the immunopathology of TB still remains unknown. In this experiment, we examined the inhibitory effect of MCL on Mtb-induced inflammatory response in mouse macrophage-like cell line Raw264.7 by downregulating the activation of nuclear factor kappa B (NF-κB) and NLRP3 inflammasome. Evidences showed that MCL decreased the secretion of Mtb-induced inflammatory cytokines (IL-1ß and TNF-α) in a dose-dependent manner. Meanwhile, MCL dramatically suppressed Mtb-induced activation of iNOS and COX2 as well as subsequent production of NO. Furthermore, MCL inhibited Mtb-induced phosphorylation of Akt (Ser 473) in Raw264.7. According to our results, MCL plays an important role in modulating Mtb-induced inflammatory response through PI3K/Akt/NF-κB pathway and subsequently downregulating the activation of NLRP3 inflammasome. Therefore, MCL may represent as a potential drug candidate in the adjuvant treatment of TB by regulating host immune response.


Asunto(s)
Antiinflamatorios/uso terapéutico , Inflamasomas/efectos de los fármacos , Inflamasomas/metabolismo , Mycobacterium tuberculosis/inmunología , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Sesquiterpenos de Guayano/uso terapéutico , Animales , Interleucina-1beta/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Fosforilación/efectos de los fármacos , Células RAW 264.7 , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo
11.
Zhongguo Yi Liao Qi Xie Za Zhi ; 39(4): 272-4, 2015 Jul.
Artículo en Zh | MEDLINE | ID: mdl-26665948

RESUMEN

The regulation of mobile medical devices is one of the hot topics in the industry now. The definition, regulation scope and requirements, potential risks of mobile medical devices were analyzed and discussed based on mobile computing techniques and the FDA guidance of mobile medical applications. The regulation work of mobile medical devices in China needs to adopt the risk-based method.


Asunto(s)
Equipos y Suministros/normas , Aplicaciones Móviles/normas , China
12.
Zhongguo Yi Liao Qi Xie Za Zhi ; 38(4): 290-1, 314, 2014 Jul.
Artículo en Zh | MEDLINE | ID: mdl-25330613

RESUMEN

Medical laser adopts optical fibers as spread media, using laser energy for the purpose of diagnostics and therapeutics. The corresponding industry standard is YY/T 0758-2009 General requirements for therapeutic laser fiber, which requires manufacturers to offer applicable wave length (or spectrum range) of the fiber, and the corresponding minimum transmission efficiency of the wave length. This research focuses on the matching of therapeutic laser fiber and laser source, to support and emphasize the importance and reasonability of relative requirements in YY/T 0758-2009.


Asunto(s)
Diseño de Equipo , Rayos Láser , Fibras Ópticas
13.
ACS Med Chem Lett ; 15(5): 595-601, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38746892

RESUMEN

Herein we describe the medicinal chemistry efforts that led to the discovery of the clinical-staged Syk inhibitor sovleplenib (41) via a structure-activity relationship investigation and pharmacokinetics (PK) optimization of a pyrido[3,4-b]pyrazine scaffold. Sovleplenib is a potent and selective Syk inhibitor with favorable preclinical PK profiles and robust anti-inflammation efficacy in a preclinical collagen-induced arthritis model. Sovleplenib is now being developed for treating autoimmune diseases such as immune thrombocytopenic purpura and warm antibody hemolytic anemia as well as hematological malignancies.

14.
Org Lett ; 23(14): 5476-5479, 2021 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-34213916

RESUMEN

Herein, a concise asymmetric synthesis of (+)-isostrychnine is achieved in nine longest-linear steps with a 16% overall yield. The key features of this synthesis include the catalytic asymmetric tandem double Michael addition of a tryptamine-derived oxindole to an alkynone to facilely forge the A/B/C ring framework, a one-pot intramolecular dehydrative condensation/lactamization reaction to efficiently establish the E/G ring system, and an allylic diazene rearrangement to introduce the pivotal olefin for the subsequent intramolecular Heck reaction.

15.
J Leukoc Biol ; 108(6): 1747-1764, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32991757

RESUMEN

Tuberculosis is a serious public health problem aggravated by the slow progress in the development of new anti-tuberculosis drugs. The hyper-reactive TB patients have suffered from chronic inflammation which could cause deleterious effects on their bodies. Therefore, it is imperative to develop an adjunctive therapy based on inflammatory modulation during Mycobacterium tuberculosis (Mtb) infection. The present study aims to investigate the immune regulatory effects of Andrographolide (Andro) on Mtb-infected macrophages and its underlying mechanisms. The results showed that Andro inhibits the production of IL-1ß and other inflammatory cytokines in a dose-dependent manner. The down-regulation of IL-1ß expression causes the declining expression of IL-8 and MCP-1 in lung epithelial cells which were co-cultured with Mtb-infected macrophages.  The inhibition of the activation of NF-κB pathway, but not the inhibition of MAPK signaling pathway, accounts for the anti-inflammatory role of Andro. Further studies elucidated that Andro could evoke the activation of autophagy to degrade NLRP3, which ultimately inhibited inflammasome activation and subsequent IL-1ß production. Finally, the relevant results demonstrated that Andro inhibited the Notch1 pathway to down-regulate the phosphorylation of Akt/mTOR and NF-κB p65 subunit. Taken together, Andro has been found to suppress the Notch1/Akt/NF-κB signaling pathway. Both Akt inhibition-induced autophagy and inhibition of the NF-κB pathway contributed to restraining the activation of NLRP3 inflammasome and subsequent IL-1ß production. Then, the decreased production of IL-1ß influenced chemokine expression in lung epithelial cells. Based on these results, anti-inflammatory effect of Andro in TB infection is merit further investigation.


Asunto(s)
Antiinflamatorios/farmacología , Diterpenos/farmacología , Sistema de Señalización de MAP Quinasas/inmunología , Macrófagos/inmunología , Mycobacterium tuberculosis/inmunología , Proteínas Proto-Oncogénicas c-akt/inmunología , Receptor Notch1/inmunología , Factor de Transcripción ReIA/inmunología , Tuberculosis/inmunología , Animales , Femenino , Macrófagos/patología , Ratones , Tuberculosis/tratamiento farmacológico , Tuberculosis/patología
16.
J Ethnopharmacol ; 252: 112605, 2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-31981749

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Secoeudesma sesquiterpenes lactone A (SESLA) is a sesquiterpene compound isolated from Inula japonica Thunb. (I. japonica). It is an herb widely distributed in Asian countries often used for the treatment of various conditions including tumors, bronchitis and bacterial and viral infections. It has been reported that SESLA could significantly inhibit the production of nitric oxide (NO) by lipopolysaccharide (LPS) in Raw264.7 cells. However, the mechanism responsible for this anti-inflammatory role and its role in the treatment of antibiotic-resistant bacterial infection, e.g., carbapenem-resistant Klebsiella pneumoniae (CRKP), remain to be investigated. AIM OF THE STUDY: This study was carried out to investigate the protective anti-inflammatory role and the underlying molecular mechanisms of SESLA in LPS or CRKP evoked inflammation. MATERIALS AND METHODS: ELISA and PCR were utilized to detect the expression of inflammatory mediators in LPS or heat-killed CRKP (HK CRKP)-stimulated immune cells containing different concentrations of SESLA. The protective role of SESLA was observed in mice challenged with a lethal dose of CRKP. Mice were intraperitoneally injected with CRKP to create a septic mouse model to evaluate the protective role of SESLA in vivo. Phosphorylated proteins, which represented the activation of signaling pathways, were examined by Western blot. RESULTS: SESLA was showed to inhibit the expression of inflammatory mediators in various macrophages and dendritic cells upon stimulation of LPS or HK CRKP. It also facilitated phagocytosis of bacteria by Raw264.7 cells. The combined use of SELSA and the ineffective antibiotic, meropenem, increased the survival rate of CRKP infected mice from 25% to 50%. ERK, NF-κB and PI3K/Akt pathways accounted for the anti-inflammatory role of SESLA with the stimulation of LPS. CONCLUSION: According to the notable anti-inflammatory effect in vitro and its joint protective effects on a septic mouse model, SESLA might act as an adjuvant drug candidate for sepsis, even those caused by antibiotic-resistant bacteria, e.g., CRKP.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Antiinflamatorios/uso terapéutico , Infecciones por Klebsiella/tratamiento farmacológico , Klebsiella pneumoniae , Lactonas/uso terapéutico , Sepsis/tratamiento farmacológico , Sesquiterpenos/uso terapéutico , Adyuvantes Inmunológicos/farmacología , Animales , Antibacterianos , Antiinflamatorios/farmacología , Carbapenémicos , Citocinas/inmunología , Farmacorresistencia Bacteriana , Femenino , Inula , Infecciones por Klebsiella/inmunología , Lactonas/farmacología , Lipopolisacáridos , Ratones , Ratones Endogámicos C57BL , Células RAW 264.7 , Sepsis/inmunología , Sesquiterpenos/farmacología
17.
Mol Immunol ; 44(11): 2850-9, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17328955

RESUMEN

Tumors actively develop different mechanisms such as immunosuppressive cytokine production to escape from immune control and limit the success of immunotherapy. More and more evidences suggest that chronic inflammation contributes to cancer development and progression. Recently, Toll-like receptors (TLRs), the receptors by which immune cells recognize microbial conserved components such as lipopolysaccharide (LPS) then initiate immune and inflammatory responses, have been found to be expressed by some kinds of tumor cells. However, what is the biological function of TLRs on tumor cells and whether human lung cancer cells can express TLRs remain to be fully understood. In the present study, we demonstrate that TLR4 is expressed on human lung cancer cell lines. TLR4 ligation promotes production of immunosuppressive cytokines TGF-beta, VEGF, proangiogenic chemokine IL-8 by human lung cancer cells. In addition, TLR4 ligation induces resistance of human lung cancer cells to TNF-alpha or TRAIL-induced apoptosis. Furthermore, we show p38MAPK activation is necessary for increased VEGF and IL-8 secretion, NF-kappaB activation contributes to apoptosis resistance of human lung cancer cells induced by LPS. Therefore, we demonstrate that TLR4 expressed on human lung cancer cells is functionally active, and may play important roles in promoting immune escape of human lung cancer cells by inducing immunosuppressive cytokines and apoptosis resistance.


Asunto(s)
Terapia de Inmunosupresión , Neoplasias Pulmonares/inmunología , Receptor Toll-Like 4/inmunología , Escape del Tumor/inmunología , Apoptosis/genética , Apoptosis/inmunología , Línea Celular Tumoral , Humanos , Inflamación , Interleucina-8/inmunología , Neoplasias Pulmonares/genética , Transducción de Señal/inmunología , Receptor Toll-Like 4/genética , Escape del Tumor/genética , Factor de Necrosis Tumoral alfa/inmunología , Factor A de Crecimiento Endotelial Vascular/inmunología
18.
Am J Transl Res ; 10(3): 670-683, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29636858

RESUMEN

Staphylococcus aureus is a Gram-positive (G+) bacterium that causes a wide range of diseases in humans and livestock. Therefore, the development of innovative and effective therapies is essential for the treatment of S. aureus-induced severe infections. Ephedrine hydrochloride (EH) is a compound derived from ephedrine and is widely used for the management of cardiovascular diseases and hypotension. The results of our previous studies demonstrated that EH has anti-inflammatory activity in macrophages and protects against endotoxic shock. However, whether EH regulates the function of dendritic cells (DCs) and the immune response in S. aureus-induced infection is unknown. In this study, the anti-inflammatory and regulatory activity of EH on DCs was evaluated. EH increased the production of anti-inflammatory cytokine IL-10 and decreased the production of proinflammatory cytokines TNF-α and IL-12 in DCs stimulated with peptidoglycan (PGN), the main cell wall component in G+ bacteria. The PI3K/Akt and p38 MAPK signaling pathways controlled EH-induced IL-10 expression and EH-inhibited TNF-α expression, respectively. The PGN-induced expression of co-stimulatory molecules CD40, CD80, CD86, and MHC class II molecule Iab was down-regulated in DCs by EH. Furthermore, EH protected the liver and kidney and increased the survival rate of mice with S. aureus-induced peritonitis. In conclusion, EH helps to keep immune homeostasis and alleviate organ damage during S. aureus-induced peritonitis. Therefore, EH may be a promising drug candidate in the treatment of S. aureus-induced severe infections and other invasive G+ bacterial infections.

19.
PPAR Res ; 2018: 6079101, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29483924

RESUMEN

Portulaca oleracea L. is a traditional Chinese medicine, which has been used as adjuvant therapy for inflammatory bowel disease (IBD). However, the mechanism of its activity in IBD still remains unclear. Since previous studies have documented the anti-inflammatory effect of peroxisome proliferator activated receptors-γ (PPAR-γ), Portulaca regulation of PPAR-γ in inflammation was examined in current study. Ulcerative colitis (UC) was generated by 5% dextran sulfate sodium (DSS) in mice and four groups were established as normal control, DSS alone, DSS plus mesalamine, and DSS plus Portulaca. Severity of UC was evaluated by body weight, stool blood form, and length of colorectum. Inflammation was examined by determination of inflammatory cytokines (TNF-a, IL-6, and IL-1a). Portulaca extract was able to attenuate development of UC in DSS model similar to the treatment of mesalazine. Moreover, Portulaca extract inhibited proinflammatory cytokines release and reduced the level of DSS-induced NF-κB phosphorylation. Furthermore, Portulaca extract restored PPAR-γ level, which was reduced by DSS. In addition, Portulaca extract protected DSS induced apoptosis in mice. In conclusion, Portulaca extract can alleviate colitis in mice through regulation of inflammatory reaction, apoptosis, and PPAR-γ level; therefore, Portulaca extract can be a potential candidate for the treatment of IBD.

20.
Front Microbiol ; 8: 2142, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29163427

RESUMEN

Tuberculosis (TB) remains a leading killer worldwide among infectious diseases and the effective control of TB is still challenging. Autophagy is an intracellular self-digestion process which has been increasingly recognized as a major host immune defense mechanism against intracellular microorganisms like Mycobacterium tuberculosis (Mtb) and serves as a key negative regulator of inflammation. Clinically, chronic inflammation surrounding Mtb can persist for decades leading to lung injury that can remain even after successful treatment. Adjunct host-directed therapy (HDT) based on both antimycobacterial and anti-inflammatory interventions could be exploited to improve treatment efficacy and outcome. Autophagy occurring in the host macrophages represents a logical host target. Here, we show that herbal medicine, baicalin, could induce autophagy in macrophage cell line Raw264.7 and caused increased killing of intracellular Mtb. Further, baicalin inhibited Mtb-induced NLRP3 inflammasome activation and subsequent inflammasome-derived IL-1ß. To investigate the molecular mechanisms of baicalin, the signaling pathways associated with autophagy were examined. Results indicated that baicalin decreased the levels of phosphorylated protein kinase B (p-Akt) and phosphorylated mammalian target of rapamycin (p-mTOR) at Ser473 and Ser2448, respectively, but did not alter the phosphorylation of p38, JNK, or ERK both in Raw264.7 and primary peritoneal macrophages. Moreover, baicalin exerted an obvious inhibitory effect on nuclear factor-kappa B (NF-κB) activity. Finally, immunofluorescence studies demonstrated that baicalin promoted the co-localization of inflammasome with autophagosome may serve as the underlying mechanism of autophagic degradative effect on reducing inflammasome activation. Together, baicalin definitely induces the activation of autophagy on the Mtb-infected macrophages through PI3K/Akt/mTOR pathway instead of MAPK pathway. Furthermore, baicalin inhibited the PI3K/Akt/NF-κB signal pathway, and both autophagy induction and NF-κB inhibition contribute to limiting the NLRP3 inflammasome as well as subsequent production of pro-inflammatory cytokine IL-1ß. Based on these results, we conclude that baicalin is a promising antimycobacterial and anti-inflammatory agent which can be a novel candidate for the development of new adjunct drugs targeting HDT for possible improved treatment.

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