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1.
J Control Release ; 368: 355-371, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432468

RESUMO

Delayed wound healing caused by bacterial infection remains a major challenge in clinical treatment. Exotoxins incorporated in bacterial extracellular vesicles play a key role as the disease-causing virulence factors. Safe and specific antivirulence agents are expected to be developed as an effective anti-bacterial infection strategy, instead of single antibiotic therapy. Plant-derived extracellular vesicle-like nanoparticles have emerged as promising therapeutic agents for skin diseases, but the elucidations of specific mechanisms of action and clinical transformation still need to be advanced. Here, dandelion-derived extracellular vesicle-like nanoparticles (TH-EVNs) are isolated and exert antivirulence activity through specifically binding to Staphylococcus aureus (S. aureus) exotoxins, thereby protecting the host cell from attack. The neutralization of TH-EVNs against exotoxins has considerable binding force and stability, showing complete detoxification effect in vivo. Then gelatin methacryloyl hydrogel is developed as TH-EVNs-loaded dressing for S. aureus exotoxin-invasive wounds. Hydrogel dressings demonstrate good physical and mechanical properties, thus achieving wound retention and controlled release of TH-EVNs, in addition to promoting cell proliferation and migration. In vivo results show accelerated re-epithelialization, promotion of collagen maturity and reduction of inflammation after treatment. Collectively, the developed TH-EVNs-laden hydrogel dressings provide a potential therapeutic approach for S. aureus exotoxin- associated trauma.


Assuntos
Anti-Infecciosos , Infecções Estafilocócicas , Taraxacum , Hidrogéis/química , Staphylococcus aureus , Cicatrização , Exotoxinas , Antibacterianos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Bandagens
2.
Blood Adv ; 8(2): 309-323, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-37967356

RESUMO

ABSTRACT: Ca2+/calmodulin-dependent protein kinase II γ (CAMKIIγ) has been identified as a potential target for treating cancer. Based on our previous study of berbamine (BBM) as a CAMKIIγ inhibitor, we have synthesized a new BBM derivative termed PA4. Compared with BBM, PA4 showed improved potency and specificity and was more cytotoxic against lymphoma and leukemia than against other types of cancer. In addition to indirectly targeting c-Myc protein stability, we demonstrated that its cytotoxic effects were also mediated via increased reactive oxygen species production in lymphoma cells. PA4 significantly impeded tumor growth in vivo in a xenograft T-cell lymphoma mouse model. Pharmacokinetics studies demonstrated quick absorption into plasma after oral administration, with a maximum concentration of 1680 ± 479 ng/mL at 5.33 ± 2.31 hours. The calculated oral absolute bioavailability was 34.1%. Toxicity assessment of PA4 showed that the therapeutic window used in our experiments was safe for future development. Given its efficacy, safety, and favorable pharmacokinetic profile, PA4 is a potential lead candidate for treating lymphoma.


Assuntos
Antineoplásicos , Benzilisoquinolinas , Leucemia , Linfoma de Células T , Humanos , Camundongos , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Benzilisoquinolinas/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
3.
Nanomaterials (Basel) ; 13(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37887896

RESUMO

Hexavalent chromium (Cr(VI)) is a typical heavy metal pollutant, making its removal from wastewater imperative. Although nanosized zero-valent iron (nZVI) and graphene-based materials are excellent remediation materials, they have drawbacks, such as agglomeration and being difficult to recycle. A facile synthesis method for decorating reduced graphene oxide (rGO) with ultrathin nZVI (within 10 nm) was explored in this study in order to develop an effective tool for Cr(VI) detoxication. Cu particles were doped in these composites for electron-transfer enhancement and were verified to improve the rate by 2.4~3.4 times. Batch experiments were conducted at different pHs, initial concentrations, ionic strengths, and humic acid (HA) concentrations. From these observations, it was found that the acid condition and appearance of Cu and rGO enhanced the treatment capacity. This procedure was fitted with a pseudo-second-order model, and the existence of NaCl and HA impeded it to some extent. Cr(VI) could be detoxified into Cr(III) and precipitated on the surface. Combining these analyses, a kinetics study, and the characterizations before and after the reaction, the removal mechanism of Cr(VI) was further discussed as a complex process involving adsorption, reduction, and precipitation. The maximum removal capacity of 156.25 mg g-1 occurred in the acid condition, providing a potential Cr(VI) remediation method.

4.
Hepatology ; 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37820064

RESUMO

BACKGROUND AND AIMS: Although the benefits of vertical sleeve gastrectomy (VSG) surgery are well known, the molecular mechanisms by which VSG alleviates obesity and its complications remain unclear. We aim to determine the role of CYP8B1 (cytochrome P450, family 8, subfamily B, polypeptide 1) in mediating the metabolic benefits of VSG. APPROACH AND RESULTS: We found that expression of CYP8B1, a key enzyme in controlling the 12α-hydroxylated (12α-OH) bile acid (BA) to non-12α-OH BA ratio, was strongly downregulated after VSG. Using genetic mouse models of CYP8B1 overexpression, knockdown, and knockout, we demonstrated that overexpression of CYP8B1 dampened the metabolic improvements associated with VSG. In contrast, short hairpin RNA-mediated CYP8B1 knockdown improved metabolism similar to those observed after VSG. Cyp8b1 deficiency diminished the metabolic effects of VSG. Further, VSG-induced alterations to the 12α-OH/non-12α-OH BA ratio in the BA pool depended on CYP8B1 expression level. Consequently, intestinal lipid absorption was restricted, and the gut microbiota (GM) profile was altered. Fecal microbiota transplantation from wild type-VSG mice (vs. fecal microbiota transplantation from wild-type-sham mice) improved metabolism in recipient mice, while there were no differences between mice that received fecal microbiota transplantation from knockout-sham and knockout-VSG mice. CONCLUSIONS: CYP8B1 is a critical downstream target of VSG. Modulation of BA composition and gut microbiota profile by targeting CYP8B1 may provide novel insight into the development of therapies that noninvasively mimic bariatric surgery to treat obesity and its complications.

5.
Molecules ; 28(14)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37513205

RESUMO

The regulation of bile acid pathways has become a particularly promising therapeutic strategy for a variety of metabolic disorders, cancers, and diseases. However, the hydrophobicity of bile acids has been an obstacle to clinical efficacy due to off-target effects from rapid drug absorption. In this report, we explored a novel strategy to design new structure fragments based on lithocholic acid (LCA) with improved hydrophilicity by introducing a polar "oxygen atom" into the side chain of LCA, then (i) either retaining the carboxylic acid group or replacing the carboxylic acid group with (ii) a diol group or (iii) a vinyl group. These novel fragments were evaluated using luciferase-based reporter assays and the MTS assay. Compared to LCA, the result revealed that the two lead compounds 1a-1b were well tolerated in vitro, maintaining similar potency and efficacy to LCA. The MTS assay results indicated that cell viability was not affected by dose dependence (under 25 µM). Additionally, computational model analysis demonstrated that compounds 1a-1b formed more extensive hydrogen bond networks with Takeda G protein-coupled receptor 5 (TGR5) than LCA. This strategy displayed a potential approach to explore the development of novel endogenous bile acids fragments. Further evaluation on the biological activities of the two lead compounds is ongoing.


Assuntos
Ácidos e Sais Biliares , Ácido Litocólico , Ácido Litocólico/farmacologia , Ácidos e Sais Biliares/farmacologia
6.
Cell Death Dis ; 14(6): 375, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365177

RESUMO

Auditory neuropathy spectrum disorder (ANSD) is a hearing impairment caused by dysfunction of inner hair cells, ribbon synapses, spiral ganglion neurons and/or the auditory nerve itself. Approximately 1/7000 newborns have abnormal auditory nerve function, accounting for 10%-14% of cases of permanent hearing loss in children. Although we previously identified the AIFM1 c.1265 G > A variant to be associated with ANSD, the mechanism by which ANSD is associated with AIFM1 is poorly understood. We generated induced pluripotent stem cells (iPSCs) from peripheral blood mononuclear cells (PBMCs) via nucleofection with episomal plasmids. The patient-specific iPSCs were edited via CRISPR/Cas9 technology to generate gene-corrected isogenic iPSCs. These iPSCs were further differentiated into neurons via neural stem cells (NSCs). The pathogenic mechanism was explored in these neurons. In patient cells (PBMCs, iPSCs, and neurons), the AIFM1 c.1265 G > A variant caused a novel splicing variant (c.1267-1305del), resulting in AIF p.R422Q and p.423-435del proteins, which impaired AIF dimerization. Such impaired AIF dimerization then weakened the interaction between AIF and coiled-coil-helix-coiled-coil-helix domain-containing protein 4 (CHCHD4). On the one hand, the mitochondrial import of ETC complex subunits was inhibited, subsequently leading to an increased ADP/ATP ratio and elevated ROS levels. On the other hand, MICU1-MICU2 heterodimerization was impaired, leading to mCa2+ overload. Calpain was activated by mCa2+ and subsequently cleaved AIF for its translocation into the nucleus, ultimately resulting in caspase-independent apoptosis. Interestingly, correction of the AIFM1 variant significantly restored the structure and function of AIF, further improving the physiological state of patient-specific iPSC-derived neurons. This study demonstrates that the AIFM1 variant is one of the molecular bases of ANSD. Mitochondrial dysfunction, especially mCa2+ overload, plays a prominent role in ANSD associated with AIFM1. Our findings help elucidate the mechanism of ANSD and may lead to the provision of novel therapies.


Assuntos
Fator de Indução de Apoptose , Cálcio , Células-Tronco Pluripotentes Induzidas , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Criança , Humanos , Recém-Nascido , Fator de Indução de Apoptose/genética , Fator de Indução de Apoptose/metabolismo , Cálcio/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucócitos Mononucleares/metabolismo , Mitocôndrias/metabolismo , Neurônios/metabolismo , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial/genética , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial/metabolismo
7.
Math Biosci Eng ; 20(4): 7234-7252, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-37161149

RESUMO

Loser-out tournament-based fireworks algorithm (LoTFWA) is a new baseline of fireworks algorithm (FWA). However, its ability to search deeply in local areas and communicate among fireworks is not satisfying enough. Therefore, this paper proposes a new triple-spark guiding strategy for LoTFWA to deal with the mentioned problems. Among the three sparks generated for guiding, one is exactly the same as the original one in LoTFWA, the second one uses the centroid of good sparks to enhance the local exploitation, and the last one is based on Differential evolution (DE) mutation and used to enhance cooperation and exploration. Experimental results show that with low computational cost, the proposed guiding strategy attains significantly better results than LoTFWA and is competitive with state-of-the-art FWA variants. Furthermore, comprehensive experiments show that the proposed strategy has the potential to combine with other FWA variants to achieve better results.

8.
J Clin Invest ; 133(14)2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37200096

RESUMO

Hypertrophic cardiomyopathy (HCM) is the most prominent cause of sudden cardiac death in young people. Due to heterogeneity in clinical manifestations, conventional HCM drugs have limitations for mitochondrial hypertrophic cardiomyopathy. Discovering more effective compounds would be of substantial benefit for further elucidating the pathogenic mechanisms of HCM and treating patients with this condition. We previously reported the MT-RNR2 variant associated with HCM that results in mitochondrial dysfunction. Here, we screened a mitochondria-associated compound library by quantifying the mitochondrial membrane potential of HCM cybrids and the survival rate of HCM-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) in galactose media. 1-Deoxynojirimycin (DNJ) was identified to rescue mitochondrial function by targeting optic atrophy protein 1 (OPA1) to promote its oligomerization, leading to reconstruction of the mitochondrial cristae. DNJ treatment further recovered the physiological properties of HCM iPSC-CMs by improving Ca2+ homeostasis and electrophysiological properties. An angiotensin II-induced cardiac hypertrophy mouse model further verified the efficacy of DNJ in promoting cardiac mitochondrial function and alleviating cardiac hypertrophy in vivo. These results demonstrated that DNJ could be a potential mitochondrial rescue agent for mitochondrial hypertrophic cardiomyopathy. Our findings will help elucidate the mechanism of HCM and provide a potential therapeutic strategy.


Assuntos
1-Desoxinojirimicina , Cardiomiopatia Hipertrófica , Animais , Camundongos , 1-Desoxinojirimicina/farmacologia , 1-Desoxinojirimicina/metabolismo , Cardiomiopatia Hipertrófica/tratamento farmacológico , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/metabolismo , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Cardiomegalia/tratamento farmacológico , Cardiomegalia/genética , Cardiomegalia/metabolismo
9.
J Zhejiang Univ Sci B ; 24(2): 172-184, 2023 Feb 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36751702

RESUMO

Auditory neuropathy spectrum disorder (ANSD) represents a variety of sensorineural deafness conditions characterized by abnormal inner hair cells and/or auditory nerve function, but with the preservation of outer hair cell function. ANSD represents up to 15% of individuals with hearing impairments. Through mutation screening, bioinformatic analysis and expression studies, we have previously identified several apoptosis-inducing factor (AIF) mitochondria-associated 1 (AIFM1) variants in ANSD families and in some other sporadic cases. Here, to elucidate the pathogenic mechanisms underlying each AIFM1 variant, we generated AIF-null cells using the clustered regularly interspersed short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system and constructed AIF-wild type (WT) and AIF-mutant (mut) (p.|T260A, p.|R422W, and p.|R451Q) stable transfection cell lines. We then analyzed AIF structure, coenzyme-binding affinity, apoptosis, and other aspects. Results revealed that these variants resulted in impaired dimerization, compromising AIF function. The reduction reaction of AIF variants had proceeded slower than that of AIF-WT. The average levels of AIF dimerization in AIF variant cells were only 34.5%|‒|49.7% of that of AIF-WT cells, resulting in caspase-independent apoptosis. The average percentage of apoptotic cells in the variants was 12.3%|‒|17.9%, which was significantly higher than that (6.9%|‒|7.4%) in controls. However, nicotinamide adenine dinucleotide (NADH) treatment promoted the reduction of apoptosis by rescuing AIF dimerization in AIF variant cells. Our findings show that the impairment of AIF dimerization by AIFM1 variants causes apoptosis contributing to ANSD, and introduce NADH as a potential drug for ANSD treatment. Our results help elucidate the mechanisms of ANSD and may lead to the provision of novel therapies.


Assuntos
Fator de Indução de Apoptose , NAD , Humanos , Fator de Indução de Apoptose/química , Fator de Indução de Apoptose/genética , Fator de Indução de Apoptose/metabolismo , NAD/metabolismo , Dimerização , Apoptose
10.
J Exp Clin Cancer Res ; 42(1): 5, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36600258

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a multifactor-driven malignant tumor with rapid progression, which causes the difficulty to substantially improve the prognosis of HCC. Limited understanding of the mechanisms in HCC impedes the development of efficacious therapies. Despite Krüpple-Like factors (KLFs) were reported to be participated in HCC pathogenesis, the function of KLF14 in HCC remains largely unexplored. METHODS: We generated KLF14 overexpressed and silenced liver cancer cells, and nude mouse xenograft models for the in vitro and in vivo study. Luciferase reporter assay, ChIP-qPCR, Co-IP, immunofluorescence were performed for mechanism research. The expression of KLF14 in HCC samples was analyzed by quantitative RT-PCR, Western blotting, and immunohistochemistry (IHC) analysis. RESULTS: KLF14 was significantly downregulated in human HCC tissues, which was highly correlated with poor prognosis. Inhibition of KLF14 promoted liver cancer cells proliferation and overexpression of KLF14 suppressed cells growth. KLF14 exerts its anti-tumor function by inhibiting Iron-responsive element-binding protein 2 (IRP2), which then causes transferrin receptor-1(TfR1) downregulation and ferritin upregulation on the basis of IRP-IREs system. This then leading to cellular iron deficiency and HCC cells growth suppression in vitro and in vivo. Interestingly, KLF14 suppressed the transcription of IRP2 via recruiting SIRT1 to reduce the histone acetylation of the IRP2 promoter, resulting in iron depletion and cell growth suppression. More important, we found fluphenazine is an activator of KLF14, inhibiting HCC cells growth through inducing iron deficiency. CONCLUSION: KLF14 acts as a tumor suppressor which inhibits the proliferation of HCC cells by modulating cellular iron metabolism via the repression of IRP2. We identified Fluphenazine, as an activator of KLF14, could be a potential compound for HCC therapy. Our findings therefore provide an innovative insight into the pathogenesis of HCC and a promising therapeutic target.


Assuntos
Carcinoma Hepatocelular , Proteína 2 Reguladora do Ferro , Ferro , Fatores de Transcrição Kruppel-Like , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Flufenazina , Regulação Neoplásica da Expressão Gênica , Homeostase , Ferro/metabolismo , Proteína 2 Reguladora do Ferro/genética , Proteína 2 Reguladora do Ferro/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo
11.
Commun Biol ; 6(1): 105, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707678

RESUMO

Long non-coding RNAs (lncRNAs) are emerging important epigenetic regulators in metabolic processes. Whether they contribute to the metabolic effects of vertical sleeve gastrectomy (VSG), one of the most effective treatments for sustainable weight loss and metabolic improvement, is unknown. Herein, we identify a hepatic lncRNA Gm19619, which is strongly repressed by VSG but highly up-regulated by diet-induced obesity and overnight-fasting in mice. Forced transcription of Gm19619 in the mouse liver significantly promotes hepatic gluconeogenesis with the elevated expression of G6pc and Pck1. In contrast, AAV-CasRx mediated knockdown of Gm19619 in high-fat diet-fed mice significantly improves hepatic glucose and lipid metabolism. Mechanistically, Gm19619 is enriched along genomic regions encoding leptin receptor (Lepr) and transcription factor Foxo1, as revealed in chromatin isolation by RNA purification (ChIRP) assay and is confirmed to modulate their transcription in the mouse liver. In conclusion, Gm19619 may enhance gluconeogenesis and lipid accumulation in the liver.


Assuntos
Lipogênese , RNA Longo não Codificante , Animais , Camundongos , Dieta Hiperlipídica , Regulação para Baixo , Gastrectomia , Gluconeogênese/genética , Lipogênese/genética , Fígado/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
12.
iScience ; 25(11): 105275, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36300003

RESUMO

Neurofibromatosis type 2 is an autosomal dominant multiple neoplasia syndrome and is usually caused by mutations in the neurofibromin 2 (NF2) gene, which encodes a tumor suppressor and initiates the Hippo pathway. However, the mechanism by which NF2 functions in the Hippo pathway isn't fully understood. Here we identified a NF2 c.770-784del mutation from a neurofibromatosis type 2 family. MD simulations showed that this mutation significantly changed the structure of the F3 module of the NF2-FERM domain. Functional assays indicated that the NF2 c.770-784del variant formed LLPS in the cytoplasm with LATS to restrain LATS plasma membrane localization and inactivated the Hippo pathway. Besides, this deletion partly caused a skipping of exon 8 and reduced the protein level of NF2, collectively promoting proliferation and tumorigenesis of meningeal cells. We identified an unrecognized mechanism of LLPS and splicing skipping for the NF2-induced Hippo pathway, which provided new insight into the pathogenesis of neurofibromatosis type 2.

13.
Mol Ther Nucleic Acids ; 30: 1-12, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36158629

RESUMO

MicroRNAs (miRNAs) are small noncoding RNAs that regulate a variety of physiological and pathological functions. miR-26a is one of the many miRNAs that have been identified as regulators of cancer development and as potential anticancer drug targets. However, the specific cellular and molecular mechanisms by which miR-26a attenuates hepatocarcinogenesis are still elusive. Here, we interrogated mouse models with miR-26a cell-specific overexpression in either hepatocytes or myeloid cells to show that miR-26a strongly attenuated the chemical-induced hepatocellular carcinoma (HCC). miR-26a overexpression broadly inhibited the inflammatory response in both hepatocytes and macrophages by decreasing several key oncogenic signaling pathways in HCC promotion. These findings thus reveal new insights into a concerted role of miR-26a in both hepatocytes and Kupffer cells to suppress hepatocarcinogenesis, thereby highlighting the potential use of miR-26a mimetics as potential approaches for the prevention and treatment of HCC.

14.
Hematol Oncol ; 40(3): 356-369, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35482553

RESUMO

Concurrent translocations of MYC and BCL2 lead to abnormal expression of both oncoproteins, which contribute to the aggressive clinical characteristics of double-hit lymphoma (DHL). An effective therapy for DHL remains an unmet clinical need. In this study, we showed that both Ca2+ /calmodulin-dependent protein kinase II δ (CAMKIIδ) and γ (CAMKIIγ) were highly expressed in DHL. Both isoforms of CAMKII stabilize c-Myc protein by phosphorylating it at Ser62, increase BCL2 expression, and promote DHL tumor growth. Inhibition of CAMKIIδ and CAMKIIγ by either berbamine (BBM) or one of its derivatives (PA4) led to the down regulation of c-Myc and BCL2 proteins. BBM/PA4 also exhibited anti-tumor efficacy in DHL cell lines and NSG xenograft models. Altogether, CAMKIIδ and CAMKIIγ appear to be critical for DHL tumor development and are promising therapeutic targets for DHL.


Assuntos
Linfoma de Células B , Linfoma Difuso de Grandes Células B , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas c-myc , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Rearranjo Gênico , Humanos , Linfoma de Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo
15.
Math Biosci Eng ; 19(3): 3202-3222, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35240827

RESUMO

Combinatorial auction is an important type of market mechanism, which can help bidders to bid on the combination of items more efficiently. The winner determination problem (WDP) is one of the most challenging research topics on the combinatorial auction, which has been proven to be NP-hard. It has more attention from researchers in recent years and has a wide range of real-world applications. To solve the winner determination problem effectively, this paper proposes a hybrid ant colony algorithm called DHS-ACO, which combines an effective local search for exploitation and an ant colony algorithm for exploration, with two effective strategies. One is a hash tabu search strategy adopted to reduce the cycling problem in the local search procedure. Another is a deep scoring strategy which is introduced to consider the profound effects of the local operators. The experimental results on a broad range of benchmarks show that DHS-ACO outperforms the existing algorithms.


Assuntos
Algoritmos
16.
Front Genet ; 13: 736988, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35309143

RESUMO

Background: 46,XY disorders/differences of sex development (46,XY DSD) are congenital conditions that result from abnormal gonadal development (gonadal dysgenesis) or abnormalities in androgen synthesis or action. During early embryonic development, several genes are involved in regulating the initiation and maintenance of testicular or ovarian-specific pathways. Recent reports have shown that MAP3K1 genes mediate the development of the 46,XY DSD, which present as complete or partial gonadal dysgenesis. Previous functional studies have demonstrated that some MAP3K1 variants result in the gain of protein function. However, data on possible mechanisms of MAP3K1 genes in modulating protein functions remain scant. Methods: This study identified a Han Chinese family with the 46,XY DSD. To assess the history and clinical manifestations for the 46,XY DSD patients, the physical, operational, ultra-sonographical, pathological, and other examinations were performed for family members. Variant analysis was conducted using both trio whole-exome sequencing (trio WES) and Sanger sequencing. On the other hand, we generated transiently transfected testicular teratoma cells (NT2/D1) and ovary-derived granular cells (KGN), with mutant or wild-type MAP3K1 gene. We then performed functional assays such as determination of steady-state levels of gender related factors, protein interaction and luciferase assay system. Results: Two affected siblings were diagnosed with 46,XY DSD. Our analysis showed a missense c.556A > G/p.R186G variant in the MAP3K1 gene. Functional assays demonstrated that the MAP3K1R186G variant was associated with significantly decreased affinity to ubiquitin (Ub; 43-49%) and increased affinity to RhoA, which was 3.19 ± 0.18 fold, compared to MAP3K1. The MAP3K1R186G led to hyperphosphorylation of p38 and GSK3ß, and promoted hyperactivation of the Wnt4/ß-catenin signaling. In addition, there was increased recruitment of ß-catenin into the nucleus, which enhanced the expression of pro-ovarian transcription factor FOXL2 gene, thus contributing to the 46,XY DSD. Conclusion: Our study identified a missense MAP3K1 variant associated with 46,XY DSD. We demonstrated that MAP3K1R186G variant enhances binding to the RhoA and improves its own stability, resulting in the activation of the Wnt4/ß-catenin/FOXL2 pathway. Taken together, these findings provide novel insights into the molecular mechanisms of 46,XY DSD and promotes better clinical evaluation.

17.
Nat Commun ; 13(1): 1135, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241650

RESUMO

The energy-dissipating capacity of brown adipose tissue through thermogenesis can be targeted to improve energy balance. Mammalian 5'-AMP-activated protein kinase, a key nutrient sensor for maintaining cellular energy status, is a known therapeutic target in Type II diabetes. Despite its well-established roles in regulating glucose metabolism in various tissues, the functions of AMPK in the intestine remain largely unexplored. Here we show that AMPKα1 deficiency in the intestine results in weight gain and impaired glucose tolerance under high fat diet feeding, while metformin administration fails to ameliorate these metabolic disorders in intestinal AMPKα1 knockout mice. Further, AMPKα1 in the intestine communicates with brown adipose tissue to promote thermogenesis. Mechanistically, we uncover a link between intestinal AMPKα1 activation and BAT thermogenic regulation through modulating anti-microbial peptide-controlled gut microbiota and the metabolites. Our findings identify AMPKα1-mediated mechanisms of intestine-BAT communication that may partially underlie the therapeutic effects of metformin.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Metformina , Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo Marrom/metabolismo , Animais , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica , Metabolismo Energético , Microbioma Gastrointestinal/fisiologia , Intestinos , Mamíferos/metabolismo , Metformina/farmacologia , Camundongos , Termogênese/fisiologia
18.
Mol Cell Endocrinol ; 543: 111543, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34995680

RESUMO

Nuclear receptor farnesoid X receptor (FXR) is generally considered a cell protector of enterohepatic tissues and a suppressor of liver cancer and colorectal carcinoma (CRC). Loss or reduction of FXR expression occurs during carcinogenesis, and the FXR level is inversely associated with the aggressive behaviors of the malignancy. Global deletion of FXR and tissue-specific deletion of FXR display distinct effects on tumorigenesis. Epigenetic silencing and inflammatory context are two main contributors to impaired FXR expression and activity. FXR exerts its antitumorigenic function via the following mechanisms: 1) FXR regulates multiple metabolic processes, notably bile acid homeostasis; 2) FXR antagonizes hepatic and enteric inflammation; 3) FXR impedes aberrant activation of some cancer-related pathways; and 4) FXR downregulates a number of oncogenes while upregulating some tumor suppressor genes. Restoring FXR functions via its agonists provides a therapeutic approach for patients with liver cancer and CRC. However, an in-depth understanding of the species-specific pharmacological effects is a prerequisite for assessing the clinical safety and efficacy of FXR agonists in human cancer treatment.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Receptores Citoplasmáticos e Nucleares/metabolismo , Ácidos e Sais Biliares/metabolismo , Neoplasias Colorretais/metabolismo , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Receptores Citoplasmáticos e Nucleares/genética
19.
Basic Clin Pharmacol Toxicol ; 130(4): 439-456, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35083862

RESUMO

Cannabidiol (CBD) is an abundant non-psychoactive phytocannabinoid in cannabis extracts which has high affinity on a series of receptors, including Type 1 cannabinoid receptor (CB1), Type 2 cannabinoid receptor (CB2), GPR55, transient receptor potential vanilloid (TRPV) and peroxisome proliferator-activated receptor gamma (PPARγ). By modulating the activities of these receptors, CBD exhibits multiple therapeutic effects, including neuroprotective, antiepileptic, anxiolytic, antipsychotic, anti-inflammatory, analgesic and anticancer properties. CBD could also be applied to treat or prevent COVID-19 and its complications. Here, we provide a narrative review of CBD's applications in human diseases: from mechanism of action to clinical trials.


Assuntos
Canabidiol/uso terapêutico , Endocanabinoides/fisiologia , Animais , Ansiolíticos/uso terapêutico , Anti-Inflamatórios não Esteroides , Anticonvulsivantes/uso terapêutico , COVID-19/prevenção & controle , Canabidiol/farmacologia , Humanos , Receptores de Canabinoides/efeitos dos fármacos , Tratamento Farmacológico da COVID-19
20.
Cell Mol Gastroenterol Hepatol ; 13(3): 809-826, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34896286

RESUMO

BACKGROUND & AIMS: Alcohol-associated liver disease (AALD) is one of the most common causes of liver injury and failure. Limited knowledge of the mechanisms underlying AALD impedes the development of efficacious therapies. Bile acid (BA) signaling was shown to participate in the progression of AALD. However, the mechanisms remain poorly understood. METHODS: C57BL/6J wild-type (WT), Takeda G-protein-coupled bile acid receptor 5 (TGR5) knockout (KO) and brown adipose tissue (BAT)-specific TGR5 knockdown mice were subjected to ethanol feeding-induced AALD. Liver samples from alcoholic hepatitis patients were used to examine the BA circulation signaling. Human Embryonic Kidney Cells 293 were used for the TGR5 reporter assay. 23(S)-methyl-lithocholic acid was used as a molecular tool to confirm the regulatory functions of BAT in the AALD mouse model. RESULTS: Ethanol feeding increased the expression of the thermogenesis genes downstream of TGR5 in BAT of WT, but not TGR5 KO, mice. TGR5 deficiency significantly blocked BAT activity and energy expenditure in mice after ethanol feeding. Alcohol increased serum BA levels in mice and human beings through altering BA transportation, and the altered BAs activated TGR5 signaling to regulate metabolism. Compared with ethanol-fed WT mice, ethanol-fed TGR5 KO mice showed less free fatty acid (FFA) ß-oxidation in BAT, leading to higher levels of FFA in the circulation, increased liver uptake of FFAs, and exacerbated AALD. BAT-specific TGR5 knockdown mice showed similar results with TGR5 KO mice in AALD. Agonist treatment significantly activated TGR5 signaling in BAT, increased thermogenesis, reduced serum FFA level, and ameliorated hepatic steatosis and injury in AALD mice, while these effects were lost in TGR5 KO mice. CONCLUSIONS: BA signaling plays a protective role in AALD by enhancing BAT thermogenesis. Targeting TGR5 in BAT may be a promising approach for the treatment of AALD.


Assuntos
Tecido Adiposo Marrom , Ácidos e Sais Biliares , Animais , Ácidos e Sais Biliares/metabolismo , Etanol/toxicidade , Humanos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
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