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1.
Transl Neurodegener ; 13(1): 35, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39049095

RESUMO

BACKGROUND: Seed amplification assays (SAA) enable the amplification of pathological misfolded proteins, including α-synuclein (αSyn), in both tissue homogenates and body fluids of Parkinson's disease (PD) patients. SAA involves repeated cycles of shaking or sonication coupled with incubation periods. However, this amplification scheme has limitations in tracking protein propagation due to repeated fragmentation. METHODS: We introduced a modified form of SAA, known as Quiescent SAA (QSAA), and evaluated biopsy and autopsy samples from individuals clinically diagnosed with PD and those without synucleinopathies (control group). Brain biopsy samples were obtained from 14 PD patients and 6 controls without synucleinopathies. Additionally, skin samples were collected from 214 PD patients and 208 control subjects. Data were analyzed from April 2019 to May 2023. RESULTS: QSAA successfully amplified αSyn aggregates in brain tissue sections from mice inoculated with pre-formed fibrils. In the skin samples from 214 PD cases and 208 non-PD cases, QSAA demonstrated high sensitivity (90.2%) and specificity (91.4%) in differentiating between PD and non-PD cases. Notably, more αSyn aggregates were detected by QSAA compared to immunofluorescence with the pS129-αSyn antibody in consecutive slices of both brain and skin samples. CONCLUSION: We introduced the new QSAA method tailored for in situ amplification of αSyn aggregates in brain and skin samples while maintaining tissue integrity, providing a streamlined approach to diagnosing PD with individual variability. The integration of seeding activities with the location of deposition of αSyn seeds advances our understanding of the mechanism underlying αSyn misfolding in PD.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Doença de Parkinson/diagnóstico , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Humanos , Animais , Camundongos , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Encéfalo/metabolismo , Encéfalo/patologia , Sensibilidade e Especificidade , Pele/metabolismo , Pele/patologia , Idoso de 80 Anos ou mais
2.
Phytomedicine ; 129: 155694, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38733904

RESUMO

BACKGROUND: Ulcerative colitis (UC) is associated with intestinal macrophage infiltration due to disruption of the mucosal barrier and bacterial invasion. Therefore, it is crucial to identify therapeutic agents capable of attenuating the macrophage-induced inflammatory response to preserve mucosal homeostasis and immune tolerance. The modified Zhenwu decoction (CDD-2103) is a novel herbal formulation developed based on the principles of Traditional Chinese medicine. To date, there are no clinically approved herbal formulations for UC with a well-known mechanism of action on macrophages. PURPOSE: The objective of this study was to systematically investigate the inhibitory effect of the active fraction of CDD-2103 in a mouse model of chronic colitis and delineate the mechanisms underlying its inhibitory action. METHODS: CDD-2103 was extracted into four fractions using organic solvents with increasing polarity. A chronic 49-day dextran sulfate sodium (DSS)-induced colitis mice model, closely resembling human clinical conditions, was used to examine the effect of CDD-2103 on chronic colitis. To confirm the effect of CDD-2103 on macrophages in this chronic colitis model, adoptive macrophage transfer and CCL2 supplementation were conducted. The mechanisms of action of CDD-2103 were further elucidated utilizing bone marrow-derived macrophages (BMDMs). Transcriptome analysis was conducted to gain insights into the underlying mechanism of action of CDD-2103 in BMDMs. RESULTS: Our in vitro and in vivo findings demonstrated that the ethanol-enriched fraction of CDD-2103 exhibited significant anti-inflammatory effects, leading to the suppression of colitis severity. This effect was associated with diminished accumulation of colonic macrophages in the lamina propria of CDD-2103-intervened colitis mice. Specifically, CDD-2103 inhibited CCR2/L2-mediated proinflammatory macrophage infiltration into the colon without affecting macrophage proliferation. Mechanistically, CDD-2103 inhibited Fyn expression-mediated p38 MAPK activation and subsequently suppressed CCR2 expression in BMDMs. CONCLUSIONS: Collectively, our study supports the potential use of CDD-2103 to limit macrophage infiltration, thereby reducing inflammation during UC treatment. CDD-2103 and the components in the ethanolic fraction are promising candidates for the development of novel drugs for UC management. Additionally, our study underscores Fyn-mediated CCR2 expression as a potential therapeutic target for the management of UC.


Assuntos
Sulfato de Dextrana , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas , Macrófagos , Camundongos Endogâmicos C57BL , Receptores CCR2 , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Masculino , Camundongos , Doença Crônica , Colite/tratamento farmacológico , Colite/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Macrófagos/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Receptores CCR2/metabolismo , Transdução de Sinais/efeitos dos fármacos
3.
Nat Commun ; 15(1): 1034, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310105

RESUMO

Obesity, a global health challenge, is a major risk factor for multiple life-threatening diseases, including diabetes, fatty liver, and cancer. There is an ongoing need to identify safe and tolerable therapeutics for obesity management. Herein, we show that treatment with artesunate, an artemisinin derivative approved by the FDA for the treatment of severe malaria, effectively reduces body weight and improves metabolic profiles in preclinical models of obesity, including male mice with overnutrition-induced obesity and male cynomolgus macaques with spontaneous obesity, without inducing nausea and malaise. Artesunate promotes weight loss and reduces food intake in obese mice and cynomolgus macaques by increasing circulating levels of Growth Differentiation Factor 15 (GDF15), an appetite-regulating hormone with a brainstem-restricted receptor, the GDNF family receptor α-like (GFRAL). Mechanistically, artesunate induces the expression of GDF15 in multiple organs, especially the liver, in mice through a C/EBP homologous protein (CHOP)-directed integrated stress response. Inhibition of GDF15/GFRAL signalling by genetic ablation of GFRAL or tissue-specific knockdown of GDF15 abrogates the anti-obesity effect of artesunate in mice with diet-induced obesity, suggesting that artesunate controls bodyweight and appetite in a GDF15/GFRAL signalling-dependent manner. These data highlight the therapeutic benefits of artesunate in the treatment of obesity and related comorbidities.


Assuntos
Fator 15 de Diferenciação de Crescimento , Obesidade , Camundongos , Masculino , Animais , Artesunato/farmacologia , Artesunato/uso terapêutico , Fator 15 de Diferenciação de Crescimento/genética , Fator 15 de Diferenciação de Crescimento/metabolismo , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Primatas , Macaca/metabolismo
4.
EMBO Mol Med ; 15(12): e17815, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37994307

RESUMO

Efficient clearance of dying cells (efferocytosis) is an evolutionarily conserved process for tissue homeostasis. Genetic enhancement of efferocytosis exhibits therapeutic potential for inflammation resolution and tissue repair. However, pharmacological approaches to enhance efferocytosis remain sparse due to a lack of targets for modulation. Here, we report the identification of columbamine (COL) which enhances macrophage-mediated efferocytosis and attenuates intestinal inflammation in a murine colitis model. COL enhances efferocytosis by promoting LC3-associated phagocytosis (LAP), a non-canonical form of autophagy. Transcriptome analysis and pharmacological characterization revealed that COL is a biased agonist that occupies a part of the ligand binding pocket of formyl peptide receptor 2 (FPR2), a G-protein coupled receptor involved in inflammation regulation. Genetic ablation of the Fpr2 gene or treatment with an FPR2 antagonist abolishes COL-induced efferocytosis, anti-colitis activity and LAP. Taken together, our study identifies FPR2 as a potential target for modulating LC3-associated efferocytosis to alleviate intestinal inflammation and highlights the therapeutic value of COL, a natural and biased agonist of FPR2, in the treatment of inflammatory bowel disease.


Assuntos
Colite , Camundongos , Animais , Fagocitose , Transdução de Sinais , Inflamação/genética , Macrófagos/metabolismo , Colite/metabolismo
5.
Int J Biol Sci ; 19(14): 4360-4375, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781034

RESUMO

Delayed intestinal mucosal healing is one of the pathogenic bases for the recurrence of inflammatory bowel disease (IBD), but how the IBD inflammatory environment impedes intestinal mucosa repair remains unclear. Adenosine diphosphate (ADP) is an endogenous ligand of P2Y1R that is highly produced at sites of inflammation. We herein identify a novel role of ADP to directly facilitate inflammation-induced epithelial permeability, delay wound healing, and disrupt tight junction integrity, and we found that P2Y1R, a receptor preferentially activated by ADP, was significantly upregulated in the colonic mucosa of ulcerative colitis (UC) patients and in colonic epithelial cells of colitis mice. Inhibition of P2Y1R significantly increased the epithelial permeability, decreased the wound healing capacity, and impaired the tight junction integrity in TNF-α-challenged Caco-2 cells. In parallel, the same effects in promoting intestinal mucosa repair were observed in DSS-induced colitis in P2Y1R-/- mice. Mechanistic investigation revealed that P2Y1R inhibition facilitated epithelial AMP-activated protein kinase (AMPK) phosphorylation and gut microbiota homeostasis reconstruction. Taken together, these findings highlight that P2Y1R activation plays an important role in impeding intestinal mucosa repair during colitis, and that P2Y1R is an attractive target for the therapy of IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Humanos , Camundongos , Animais , Células CACO-2 , Colite/induzido quimicamente , Colite/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Difosfato de Adenosina/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
6.
Biomater Sci ; 11(12): 4370-4384, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37144899

RESUMO

Amino acid-based poly(ester urea urethane) (AA-PEUU) is developed from amino acid-based ester urea building blocks interconnected with urethane blocks functionalized with poly(ethylene glycol) (PEG). Each functional block consists of structural design features that could impact the properties and performances of AA-PEUU as a nanocarrier for the systemic delivery of gambogic acid (GA). The multifunctional AA-PEUU structure provides broad tunability to enable the optimization of nanocarriers. The study investigates the structure-property relationship by fine-tuning the structure of AA-PEUU, including the amino acid type, hydrocarbons, the ratio of functional building blocks, and PEGylation, to identify the nanoparticle candidate with optimized delivery performances. Compared to free GA, the optimized PEUU nanocarrier improves the intratumoral distribution of GA by more than 9-fold, which significantly enhances the bioavailability and persistence of GA after intravenous administration. In an MDA-MB-231 xenograft mouse model, GA delivered by the optimized AA-PEUU nanocarrier exhibits significant tumor inhibition, apoptosis induction, and the anti-angiogenesis effect. The study demonstrates the potency of engineering AA-PEUU nanocarriers with tailor-designed structures and versatile tunability for the systemic delivery of therapeutics in the treatment of triple negative breast tumor.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Camundongos , Animais , Aminoácidos , Uretana , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Ureia , Ésteres , Nanopartículas/química
7.
Cancer Lett ; 555: 216039, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36528182

RESUMO

Gut microbiota play critical roles in the development of colorectal cancer (CRC) metastasis, but the underlying mechanisms remain elusive. This review discusses the molecular mechanisms by which the gut microbiota contribute to a tumor-permissive microenvironment and facilitate malignant transformation and dissemination of tumor cells, thereby mediating CRC metastasis.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Humanos , Neoplasias Colorretais/patologia , Microambiente Tumoral
8.
Carbohydr Polym ; 296: 119952, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36088031

RESUMO

The gut cell wall is considered an impenetrable barrier to orally administrated polysaccharides. We recently reported a selective lymphatic route for Radix Astragali polysaccharide RAP to enter Peyer's patches (PPs) to trigger immune responses. However, how RAP enters PPs is unclear. Herein, we screened the intestinal epithelial cells of mice and found that the follicle-associated epithelium cells were specifically bound with FITC-RAP. Further studies in vitro and in vivo revealed that RAP was efficiently transported by microfold (M) cells. We also confirmed that M cell-transported RAP directly contacted dendritic cells. More importantly, for the first time, we verified this interesting M cell-mediated transcytosis of RAP in the human distal ileum. Mechanistically, we identified M cells to be the transporter cells that independently deliver RAP into the lymphatic system to trigger immune responses. This interesting transcytosis mechanism might apply to many other immunomodulatory polysaccharides orally dosed to human body.


Assuntos
Astrágalo , Nódulos Linfáticos Agregados , Células Epiteliais/metabolismo , Epitélio , Humanos , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia
9.
Cells ; 11(14)2022 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-35883602

RESUMO

Spexin (SPX) is a novel peptide involved in glucose and lipid metabolism and suppresses hepatic total bile acid levels by inhibiting hepatic cholesterol 7α-hydroxylase 1 expression. As important mediators for glycolysis/gluconeogenesis and lipid metabolism, the effects of bile acids on SPX expression is yet to be understood. By using SMMC7721 and BEL-7402 cell lines, we screened the effects of bile acids and found that chenodeoxycholic acid (CDCA) and deoxycholic acid (DCA) can stimulate SPX gene transcription. Both CDCA and DCA were able to stimulate SPX mRNA expression in the liver but not colon and ileum in mice. In SMMC7721 and BEL-7402 cells, CDCA- and DCA-induced SPX promoter activity was mimicked by bile acid receptor FXR and TGR5 activation and suppressed by FXR and TGR5 silencing. Adenylate cyclase (AC)/cyclic adenosine monophosphate (cAMP) activators significantly increased SPX promoter activity whereas the inhibitors for AC/CAMP/protein kinase A (PKA) and mitogen-activated protein kinases (MAPK) pathway attenuated CDCA- and DCA-induced SPX transcription. Thus, CDCA and DCA stimulate SPX expression at the hepatic level through FXR and TGR5 mediated AC/cAMP/PKA and MAPK cascades.


Assuntos
Ácidos e Sais Biliares , Ácido Quenodesoxicólico , Hormônios Peptídicos , Animais , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/farmacologia , Ácido Quenodesoxicólico/farmacologia , Colesterol 7-alfa-Hidroxilase/metabolismo , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Fígado/metabolismo , Camundongos , Hormônios Peptídicos/genética , Hormônios Peptídicos/metabolismo , Regiões Promotoras Genéticas/genética
10.
Sci Adv ; 8(22): eabm9603, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35658029

RESUMO

Flavanols are privileged heterocyclic compounds in medicinal chemistry. It is notable to develop an efficient and straightforward protocol for accessing chiral flavanols with precise control of the stereocenters. Here, a highly efficient kinetic resolution of chromenes was reported via Cu-catalyzed asymmetric hydroboration. This previously unidentified approach features a one-step synthesis of chiral flavan-3-ols containing two vicinal stereogenic centers via a highly efficient kinetic resolution (s factor up to 1060, >99% ee for most products). In addition, the anti-inflammation effects of these diversified flavan-3-ols were studied by the in vitro experiments and RNA sequencing analysis. These flavan-3-ols showed inhibitory effects on the secretion of pro-inflammation cytokines including interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-α (TNF-α), as well as inhibiting the inflammation responses through down-regulating the gene transcriptions closely related to PI3K-Akt signaling pathway and TNF signaling pathway. The results suggested that these newly synthesized flavan-3-ols have the potential to be lead compounds for anti-inflammatory drugs.


Assuntos
Benzopiranos , Cobre/química , Fosfatidilinositol 3-Quinases , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Benzopiranos/farmacologia , Catálise , Humanos , Inflamação/tratamento farmacológico
11.
Carbohydr Polym ; 292: 119653, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725160

RESUMO

Gut barrier makes a huge research gap between in vivo and in vitro studies of orally bioactive polysaccharides: whether/how they contact the related cells in vivo. A hyperbranched heteroglycan RAP from Radix Astragali, exerting antitumor and immunomodulatory effects in vitro and in vivo, is right an example. Here, we determined first that RAP's antitumor activity is immune-dependent. Being undegraded and non-absorbing, RAP quickly entered Peyer's patches (PPs) in 1 h where it directly targeted follicle dendritic cells and initiated antitumor immune responses. RAP was further delivered to mesenteric lymph node, bone marrow, and tumor. By contrast, the control Dendrobium officinale polysaccharide did not enter PPs. These findings revealed a blood/microbiota-independent and selective lymphatic route for orally administrated RAP to directly contact immune cells and trigger antitumor immune responses. This route bridges the research gap between the in vitro and in vivo studies and might apply to many other bioactive polysaccharides.


Assuntos
Medicamentos de Ervas Chinesas , Nódulos Linfáticos Agregados , Astragalus propinquus , Imunidade , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia
12.
Theranostics ; 12(7): 3329-3344, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547744

RESUMO

CRISPR-Cas9 is a Nobel Prize-winning robust gene-editing tool developed in the last decade. This technique enables a stable genetic engineering method with high precision on the genomes of all organisms. The latest advances in the technology include a genome library screening approach, which can detect survival-essential and drug resistance genes via gain or loss of function. The versatile machinery allows genomic screening for gene activation or inhibition, and targets non-coding sequences, such as promoters, miRNAs, and lncRNAs. In this review, we introduce the emerging high-throughput CRISPR-Cas9 library genome screening technology and its working principles to detect survival and drug resistance genes through positive and negative selection. The technology is compared with other existing approaches while focusing on the advantages of its variable applications in anti-cancer drug discovery, including functions and target identification, non-coding RNA information, actions of small molecules, and drug target discoveries. The combination of the CRISPR-Cas9 system with multi-omic platforms represents a dynamic field expected to advance anti-cancer drug discovery and precision medicine in the clinic.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Engenharia Genética , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética
13.
Chin Med ; 17(1): 31, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236375

RESUMO

BACKGROUND: Constipation is a common problem among advanced cancer patients; however, many of them find limited effective from current therapies. Thus, we aimed to test the effect of a traditional Chinese herbal formula, modified MaZiRenWan (MZRW), by comparing with placebo among palliative cancer patients with constipation. METHODS: This is a randomized, double-blind, placebo-controlled trial. Participants aged over 18 were recruited and randomized to MZRW or placebo group in addition to current prescriptions (including ongoing laxatives treatment) for two weeks. Exclusion criteria included cognitive impairment, presence of a colostomy or gastrointestinal obstruction and estimated life expectancy of less than one month. Individualized modification of MZRW was allowed according to the traditional Chinese medicine (TCM) pattern of patient. The primary outcome was the global assessment of improvement, which reflected whether the constipation had improved, remained the same or worsened. RESULTS: Sixty patients, with mean age 75.2 years (range 47-95 years), were randomized to MZRW or placebo group. Among the MZRW group, 59.3% (16/27) had improvement in the global assessment score, as compared with 28.6% (8/28) of the placebo group (p-value = 0.022). Besides, the MZRW group had significant increase in stool frequency, and reduction in constipation severity and straining of defecation (p-value < 0.05). No serious adverse event was reported due to the research medication. CONCLUSION: This pilot trial suggests modified MZRW is well-tolerated and effective for relief of constipation in patients with advance cancer. It could be considered as a potential treatment option for constipation in palliative care. TRIAL REGISTRATION: The trial had been registered in ClinicalTrials.gov with identifier number NCT02795390 [ https://clinicaltrials.gov/ct2/show/NCT02795390 ] on June 10, 2016.

14.
Am J Chin Med ; 50(3): 723-732, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35331086

RESUMO

Constipation is a very common medical condition worldwide, negatively affecting patients' quality of life and healthcare system. Rhubarb, senna leaf, and aloe are three frequently used herbal medications for achieving regular bowel movement. Rhubarb is also a key ingredient in MaZiRenWan, a Chinese medicine formula used every so often for constipation in oriental countries. We reviewed and summarized the major chemical components from these three botanicals, including dianthrones, anthraquinone glycosides, free anthraquinones, and other polyphenols. The purgative actions of these constituents have been compared. Anthraquinone, especially its dianthrone compounds such as sennoside A and sennoside B, as natural stimulant laxatives, possesses significant effects to promote gastrointestinal motility and relieve functional constipation. Furthermore, the safety, reported side effects, and other benefits of anthraquinone compounds are presented. To date, many anti-constipation natural products are being used but their research is relatively limited, and thus, more investigations in this field are indeed needed.


Assuntos
Plantas Medicinais , Rheum , Antraquinonas/uso terapêutico , Constipação Intestinal/tratamento farmacológico , Humanos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Qualidade de Vida , Rheum/química , Senosídeos
15.
Cell Commun Signal ; 20(1): 34, 2022 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-35305671

RESUMO

BACKGROUND: KRAS mutation is one of the dominant gene mutations in colorectal cancer (CRC). Up to present, targeting KRAS for CRC treatment remains a clinical challenge. WNT974 (LGK974) is a porcupine inhibitor that interferes Wnt signaling pathway. Artesunate (ART) is a water-soluble semi-synthetic derivative of artemisinin. METHODS: The synergistic effect of ART and WNT974 combination in reducing CRC cell viability was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. RT-PCR was utilized for the mRNA levels of KRAS, CUL7, ANAPC2, UBE2M, RNF123, SYVN1, or ß-TrCP. Western blot assay was utilized for the protein levels of NRAS, HRAS, KRAS, ANAPC2, ß-TrCP, GSK-3ß, p-Akt (Ser473), t-Akt, p-PI3K (Tyr458), t-PI3K, p-mTOR (Ser2448), t-mTOR. Xenograft mouse model assay was performed for the anti-CRC effect of combination of ART and WNT974 in vivo. IHC assay was utilized for the levels of KRAS, ß-TrCP, GSK-3ß or ANAPC2 in tumor tissues. RESULTS: Our study shows that the combination of WNT974 and ART exhibits synergistic effect in reducing CRC growth. The combination treatment significantly reduces KRAS protein level and activity in CRC cells. Interestingly, the combination treatment increases E3 ligases ANAPC2 expression. Our data show that overexpression of ANAPC2 significantly reduces KRAS protein levels, which is reversed by MG132. Knockdown of ANAPC2 in CRC abolishes the combination treatment-reduce KRAS expression. Besides, the treatment also increases the expressions of GSK-3ß and E3 ligase ß-TrCP that is known to degrade GSK-3ß-phosphorylated KRAS protein. Knockdown of ß-TrCP- and inhibition of GSK-3ß abolish the combination treatment-induce KRAS ubiquitination and reduction in expression. Last but not least, combination treatment suppresses PI3K/Akt/m-TOR signaling pathway. CONCLUSIONS: Our data clearly show that the combination treatment significantly enhances KRAS protein degradation via the ubiquitination ubiquitin-proteasome pathway, which is also demonstrated in xenograft mouse model. The study provides strong scientific evidence for the development of the combination of WNT974 and ART as KRAS-targeting therapeutics for CRC treatment. Video Abstract.


Assuntos
Ubiquitina-Proteína Ligases , Proteínas Contendo Repetições de beta-Transducina , Animais , Subunidade Apc2 do Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Artesunato/farmacologia , Linhagem Celular Tumoral , Proteínas Culina , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Pirazinas , Piridinas , Serina-Treonina Quinases TOR/metabolismo , Enzimas de Conjugação de Ubiquitina , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinas/metabolismo , Via de Sinalização Wnt , Proteínas Contendo Repetições de beta-Transducina/genética , Proteínas Contendo Repetições de beta-Transducina/metabolismo
16.
Int J Med Sci ; 19(1): 175-185, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34975311

RESUMO

Our previous study found that the combination of halofuginone (HF) and artemisinin (ATS) synergistically arrest colorectal cancer (CRC) cells at the G1/G0 phase of the cell cycle; however, it remains unclear whether HF-ATS induces cell death. Here we report that HF-ATS synergistically induced caspase-dependent apoptosis in CRC cells. Specifically, both in vitro and in vivo experiments showed that HF or HF-ATS induces apoptosis via activation of caspase-9 and caspase-8 while only caspase-9 is involved in ATS-induced apoptosis. Furthermore, we found HF or HF-ATS induces autophagy; ATS can't induce autophagy until caspase-9 is blocked. Further analyzing the crosstalk between autophagic and caspase activation in CRC cells, we found autophagy is essential for activation of caspase-8, and ATS switches to activate capase-8 via induction of autophagy when caspase-9 is inhibited. When apoptosis is totally blocked, HF-ATS switches to induce autophagic cell death. This scenario was then confirmed in studies of chemoresistance CRC cells with defective apoptosis. Our results indicate that HF-ATS induces cell death via interaction between apoptosis and autophagy in CRC cells. These results highlight the value of continued investigation into the potential use of this combination in cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Artemisininas/farmacologia , Neoplasias Colorretais/patologia , Piperidinas/farmacologia , Quinazolinonas/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Artemisininas/uso terapêutico , Autofagia/efeitos dos fármacos , Caspase 8/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Sinergismo Farmacológico , Ativação Enzimática , Humanos , Piperidinas/uso terapêutico , Quinazolinonas/uso terapêutico , Receptor Cross-Talk
17.
Cell Death Dis ; 12(11): 1053, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34741022

RESUMO

Currently, no frontline treatment is effective for the late-stage colorectal cancer (CRC). Understanding the molecular differences in different stages of CRC can help us to identify the critical therapeutic targets for designing therapeutic strategy. Our data show that c-Myc protein is highly expressed in late-stage CRC when compared with early-stage CRC in both clinical samples and in cell lines representing different cancer stages. Given that c-Myc is a well-known oncogenic driver in CRC, its high expression in the late-stage CRC may represent a critical therapeutic target for treating the cancer. Dihydroartemisinin treatment significantly increases c-Myc protein degradation and hence reduces its expression in CRC. The treatment also reduces CRC cell viability. Interestingly, dihydroartemisinin exhibits a more potent growth-inhibitory effect in late-stage CRC than the early-stage CRC. The treatment also possesses potent growth-inhibitory effects in mouse models bearing c-Myc-overexpressed CRC. The reduced c-Myc level and its reduced transcriptional activity reduce the expressions of acetyl-CoA carboxylase, fatty acid synthase, carnitine-palmitoyltransferase-1, and medium-chain acyl-CoA dehydrogenase in the cancer cells. Lipidomics study also shows that dihydroartemisinin treatment changes the metabolic phenotypes in CRC, reduces oxygen consumption, respiration, and ATP production, hence reduces the cell proliferation and induces apoptosis. Our study provides strong pharmacological evidence to support the translation of dihydroartemisinin for the treatment of late-stage CRC by targeting c-Myc.


Assuntos
Artemisininas/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Animais , Apoptose/efeitos dos fármacos , Artemisininas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Ácidos Graxos/análise , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Antígeno Ki-67/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Medições Luminescentes , Camundongos Endogâmicos BALB C , Camundongos Nus , Estadiamento de Neoplasias , Fenótipo , Análise de Componente Principal , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transcrição Gênica/efeitos dos fármacos
19.
J Med Chem ; 64(23): 17051-17062, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34699215

RESUMO

Triple-negative breast cancer (TNBC) is a heterogeneous subtype of breast cancer with poor prognosis. Here, we present a peptide-drug conjugate (PDC)─bradykinin-potentiating peptide-paclitaxel (BPP-PTX) conjugate─synthesized by conjugating BPP9a with PTX via a succinyl linker. BPP-PTX targets the angiotensin-converting enzyme (ACE) on TNBC cells. ACE was found to be ectopically expressed in two TNBC cell lines but was absent in both the receptor-positive breast cancer cell line and healthy kidney cell line. Overexpression, knockdown, and competitive inhibition experiments demonstrated ACE-mediated cytotoxicity of BPP-PTX. In vivo, ACE-positive tumors were enriched with BPP-PTX, with the PDC being better tolerated than plain PTX. Compared with plain PTX, BPP-PTX exhibited improved tumor-suppressive effects in MDA-MB-468 xenografted female nude mice. Meanwhile, BPP-PTX resulted in less body weight loss and white blood cell reduction toxicity. These results collectively imply the novelty, efficacy, and low-toxicity profile of BPP-PTX as a potential therapeutic for ACE-positive TNBC.


Assuntos
Bradicinina/química , Oligopeptídeos/farmacologia , Paclitaxel/farmacologia , Peptidil Dipeptidase A/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Nus , Oligopeptídeos/química , Oligopeptídeos/farmacocinética , Paclitaxel/química , Distribuição Tecidual , Neoplasias de Mama Triplo Negativas/enzimologia
20.
Front Pharmacol ; 12: 690501, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381360

RESUMO

Colorectal cancer (CRC) has become a global public health problem because of its high incidence and mortality rate worldwide. The previous clinical treatment for CRC mainly involves conventional surgery, chemotherapy, and radiotherapy. With the development of tumor molecular targeted therapy, small molecule inhibitors present a great advantage in improving the survival of patients with advanced CRC. However, various side effects and drug resistance induced by chemotherapy are still the major obstacles to improve the clinical benefit. Thus, it is crucial to find new and alternative drugs for CRC treatment. Traditional Chinese medicines (TCMs) have been proved to have low toxicity and multi-target characteristics. In the last few decades, an increasing number of studies have demonstrated that TCMs exhibit strong anticancer effects in both experimental and clinical models and may serve as alternative chemotherapy agents for CRC treatment. Notably, Wnt/ß-catenin signaling pathway plays a vital role in the initiation and progression of CRC by modulating the stability of ß-catenin in the cytoplasm. Targeting Wnt/ß-catenin pathway is a novel direction for developing therapies for CRC. In this review, we outlined the anti-tumor effects of small molecular inhibitors on CRC through Wnt/ß-catenin pathway. More importantly, we focused on the potential role of TCMs against tumors by targeting Wnt/ß-catenin signaling at different stages of CRC, including precancerous lesions, early stage of CRC and advanced CRC. Furthermore, we also discussed perspectives to develop potential new drugs from TCMs via Wnt/ß-catenin pathway for the treatment of CRC.

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