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1.
BMC Genomics ; 24(1): 414, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488473

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive liver fat deposition, and progresses to liver cirrhosis, and even hepatocellular carcinoma. However, the invasive diagnosis of NAFLD with histopathological evaluation remains risky. This study investigated potential genes correlated with NAFLD, which may serve as diagnostic biomarkers and even potential treatment targets. METHODS: The weighted gene co-expression network analysis (WGCNA) was constructed based on dataset E-MEXP-3291. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to evaluate the function of genes. RESULTS: Blue module was positively correlated, and turquoise module negatively correlated with the severity of NAFLD. Furthermore, 8 driving genes (ANXA9, FBXO2, ORAI3, NAGS, C/EBPα, CRYAA, GOLM1, TRIM14) were identified from the overlap of genes in blue module and GSE89632. And another 8 driving genes were identified from the overlap of turquoise module and GSE89632. Among these driving genes, C/EBPα (CCAAT/enhancer binding protein α) was the most notable. By validating the expression of C/EBPα in the liver of NAFLD mice using immunohistochemistry, we discovered a significant upregulation of C/EBPα protein in NAFLD. CONCLUSION: we identified two modules and 16 driving genes associated with the progression of NAFLD, and confirmed the protein expression of C/EBPα, which had been paid little attention to in the context of NAFLD, in the present study. Our study will advance the understanding of NAFLD. Moreover, these driving genes may serve as biomarkers and therapeutic targets of NAFLD.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Perfilação da Expressão Gênica
2.
Phytother Res ; 37(11): 5341-5353, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37700535

RESUMO

BACKGROUND AND AIM: Our previous study has revealed that OEA promotes motor function recovery in the chronic stage of ischemic stroke. However, the neuroprotective mechanism of OEA on motor function recovery after stroke still is unexplored. Therefore, the aim of this study was to explore the effects of OEA treatment on angiogenesis, neurogenesis, and white matter repair in the peri-infarct region after cerebral ischemia. EXPERIMENTAL PROCEDURE: The adult male rats were subjected to 2 h of middle cerebral artery occlusion. The rats were treated with 10 and 30 mg/kg OEA or vehicle daily starting from day 2 after ischemia induction until they were sacrificed. KEY RESULTS AND CONCLUSIONS: The results revealed that OEA increased cortical angiogenesis, neural progenitor cells (NPCs) proliferation, migration, and differentiation. OEA treatment enhanced the survival of newborn neurons and oligodendrogenesis, which eventually repaired the cortical neuronal injury and improved motor function after ischemic stroke. Meanwhile, OEA treatment promoted the differentiation of oligodendrocyte progenitor cells (OPCs) and oligodendrogenesis by activating the PPARα signaling pathway. Our results showed that OEA restores motor function by facilitating cortical angiogenesis, neurogenesis, and white matter repair in rats after ischemic stroke. Therefore, we demonstrate that OEA facilitates functional recovery after ischemic stroke and propose the hypothesis that the long-term application of OEA mitigates the disability after stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Substância Branca , Ratos , Masculino , Animais , Substância Branca/metabolismo , PPAR alfa/metabolismo , Isquemia Encefálica/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Neurogênese , Diferenciação Celular , Oligodendroglia/metabolismo
3.
Pharmacology ; 107(5-6): 281-289, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35325888

RESUMO

AIM: Recent evidence indicates that neuroinflammation and oxidative stress play vital roles in the pathological process of major depressive disorder (MDD). Cinnamic acid (CA), a naturally occurring organic acid, has been reported to ameliorate neuroinflammation and oxidative stress for treatment of diabetes-related memory deficits. Here, we explored whether CA pretreatment ameliorated lipopolysaccharide (LPS)-induced depressive-like behaviors in mice by suppressing neuroinflammation and by improving oxidative stress status. METHODS: The mice were treated with CA, vehicle, or fluoxetine as a positive control. After 14 days, LPS (1 mg/kg, i.p.) or saline was administered. The depression-like behaviors were examined by the sucrose preference test (SPT), the forced swimming test (FST), and the tail suspension test (TST). Furthermore, the levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), and brain-derived neurotrophic factor (BDNF) in the hippocampus and cortex of mice were assayed. RESULTS: Our results demonstrated that CA pretreatment at the doses of 100 and 200 mg/kg significantly attenuated depressive-like behaviors in the TST, FST, and SPT. In addition, not only the upregulation of pro-inflammatory cytokines (IL-6 and TNF-α) but also oxidative stress parameters including SOD, GSH, and MDA in the hippocampus and cortex of mice treated with LPS were dramatically improved by CA pretreatment. Finally, CA pretreatment strikingly ameliorated the downregulation of BDNF induced by LPS in the hippocampus and cortex of mice. CONCLUSION: Our results indicated that CA may have therapeutic potential for MDD treatment through attenuating the LPS-induced inflammation and oxidative stress along with significant improvement of BDNF impairment.


Assuntos
Transtorno Depressivo Maior , Lipopolissacarídeos , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cinamatos , Depressão/induzido quimicamente , Depressão/tratamento farmacológico , Glutationa/metabolismo , Hipocampo/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/toxicidade , Camundongos , Doenças Neuroinflamatórias , Estresse Oxidativo , Superóxido Dismutase , Fator de Necrose Tumoral alfa/metabolismo
4.
Pharmacol Res ; 161: 105123, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32822867

RESUMO

Breast cancer (BC) is the most common cancer in women and, among different BC subtypes, triple negative (TN) and human epidermal growth factor receptor 2 (HER2)-positive BCs have the worst prognosis. In this study, we investigated the anticancer activity of the root ethanolic and hexane extracts from Lithospermum erythrorhizon, a traditional Chinese herbal medicine known also as tzu ts'ao or tzu-ken, against in vitro and in vivo models of TNBC and HER2-positive BC. Treatment with L. erythrorhizon root extracts resulted in a dose-dependent inhibition of BC cell viability and in a significant reduction of the growth of TNBC cells transplanted in syngeneic mice. Acetylshikonin, a naphthoquinone, was identified as the main bioactive component in extracts and was responsible for the observed antitumor activity, being able to decrease BC cell viability and to interfere with autochthonous mammary carcinogenesis in Δ16HER2 transgenic mice. Acetylshikonin anticancer effect depends on its ability to act as a potent inhibitor of dihydrofolate reductase (DHFR), to down-regulate key mediators governing cancer growth and progression, such as HER2, Src and STAT3, and to induce apoptosis by caspase-3 activation. The accumulation of acetylshikonin in blood samples as well as in brain, kidney, liver and tumor tissues was also investigated by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) highlighting that L. erythrorhizon treatment is effective in delivering the active compound into the target tissues. These results provide evidence that L. erythrorhizon extract and in particular its main component acetylshikonin are effective against aggressive BC subtypes and reveal new acetylshikonin mechanisms of action.


Assuntos
Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/prevenção & controle , Antagonistas do Ácido Fólico/farmacologia , Lithospermum , Receptor ErbB-2/metabolismo , Tetra-Hidrofolato Desidrogenase/metabolismo , Animais , Antraquinonas/isolamento & purificação , Antraquinonas/farmacocinética , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Antagonistas do Ácido Fólico/isolamento & purificação , Antagonistas do Ácido Fólico/farmacocinética , Humanos , Lithospermum/química , Camundongos Transgênicos , Raízes de Plantas , Receptor ErbB-2/genética , Transdução de Sinais , Distribuição Tecidual , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Nano Lett ; 18(5): 2976-2983, 2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29714487

RESUMO

Freestanding nanomaterials (such as nanowires, nanoribbons, and nanotubes) are known to exhibit ultralarge elastic strains and ultrahigh strengths. However, harnessing their superior intrinsic mechanical properties in bulk composites has proven to be difficult. A recent breakthrough has overcome this difficulty by using a martensitic phase transforming matrix in which ultralarge elastic strains approaching the theoretical limit is achieved in Nb nanowires embedded in the matrix. This discovery, breaking a long-standing challenge, still limits our ability of harnessing the exceptional properties of nanomaterials and developing ultrahigh strength bulk materials to a narrow selection of phase transforming alloy matrices. In this study, we investigated the possibility to harness the intrinsic mechanical properties of nanoinclusions in conventional dislocation slip matrix based on a principle of synergy between the inclusion and the matrix. The small spacing between the densely populated hard and dislocation-impenetrable nanoinclusions departmentalize the plastic matrix into small domains to effectively impede dislocation motion within the matrix, inducing significant strengthening and large local elastic strains of the matrix, which in turn induced large elastic strains in the nanoinclusions. This dual phase synergy is verified in a Ti3Sn inclusions/B2-NiTi(Fe) plastic matrix model materials system. The maximum elastic strain of Ti3Sn inclusion obtained in the dislocation slip matrix is comparable to that achieved in a phase transforming matrix. This finding opens new opportunities for the development of high-strength nanocomposites.

6.
J Am Chem Soc ; 137(23): 7397-403, 2015 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-25986928

RESUMO

Both the ligand effect and surface strain can affect the electrocatalytic reactivity. In that matter exists a need to be fundamentally understood; however, there is no effective strategy to isolate the strain effect in electrocatalytic systems. In this research we show how the elastic strain in a platinum nanofilm varies the catalytic activity for the oxygen reduction reaction, a key barrier to the wide applications of fuel cells. NiTi shape memory alloy was selected as the substrate to strain engineer the deposited Pt nanofilm in both compressively and tensilely strained states by taking advantage of the two-way shape memory effect for the first time. We demonstrate that compressive strain weakens the Pt surface adsorption and hence improves the ORR activity, which reflects in a 52% enhancement of the kinetic rate constant and a 27 mV positive shift of the half-wave potential for the compressively strained 5 nm Pt compared to the pristine Pt. Tensile strain has the opposite effect, which is in general agreement with the proposed d-band theory.

7.
Acta Biochim Biophys Sin (Shanghai) ; 47(6): 414-21, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25908389

RESUMO

Glioma which has strong proliferation and angiogenesis ability is the most common and malignant primary tumor in central nervous system. Pituitary tumor transforming gene (PTTG) is found in pituitary tumor, and plays important role in cell proliferation, cell cycle, cell apoptosis, and angiogenesis. However, the role of PTTG in glioma is still incompletely investigated. Here, we explored the correlation between PTTG and glioma grade, as well as micro-vessel density (MVD). In addition, siRNA was used to silence PTTG expression in glioma cell lines including U87MG, U251, and SHG44. Cell proliferation, apoptosis, invasion, and angiogenesis were studied both in vitro and in vivo. Our results demonstrated that PTTG expression was significantly up-regulated in glioma, and had positive correlation with glioma grade and MVD. Silencing of PTTG inhibited glioma cell proliferation, migration/invasion, and angiogenesis, induced cell apoptosis, suppressed cell invasion, and arrested cell cycle at G0/G1 stage. Silencing of PTTG could also inhibit tumor growth, invasion, and angiogenesis in vivo. Our data indicated that PTTG might be a potential target for glioma treatment.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Securina/efeitos dos fármacos , Animais , Apoptose , Neoplasias Encefálicas/patologia , Proliferação de Células , Inativação Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Securina/genética
8.
Nanomaterials (Basel) ; 14(16)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39195369

RESUMO

Recent advancements in nanomedicine and biotechnology have unveiled the remarkable potential of plant-derived extracellular vesicles (PDEVs) as a novel and promising approach for cancer treatment. These naturally occurring nanoscale particles exhibit exceptional biocompatibility, targeted delivery capabilities, and the capacity to load therapeutic agents, positioning them at the forefront of innovative cancer therapy strategies. PDEVs are distinguished by their unique properties that facilitate tumor targeting and penetration, thereby enhancing the efficacy of drug delivery systems. Their intrinsic biological composition allows for the evasion of the immune response, enabling the efficient transport of loaded therapeutic molecules directly to tumor sites. Moreover, PDEVs possess inherent anti-cancer properties, including the ability to induce cell cycle arrest and promote apoptotic pathways within tumor cells. These vesicles have also demonstrated antimetastatic effects, inhibiting the spread and growth of cancer cells. The multifunctional nature of PDEVs allows for the simultaneous delivery of multiple therapeutic agents, further enhancing their therapeutic potential. Engineering and modification techniques, such as encapsulation, and the loading of therapeutic agents via electroporation, sonication, and incubation, have enabled the customization of PDEVs to improve their targeting efficiency and therapeutic load capacity. This includes surface modifications to increase affinity for specific tumor markers and the encapsulation of various types of therapeutic agents, such as small molecule drugs, nucleic acids, and proteins. Their plant-derived origin offers an abundant and renewable source to produce therapeutic vesicles, reducing costs and facilitating scalability for clinical applications. This review provides an in-depth analysis of the latest research on PDEVs as emerging anti-cancer agents in cancer therapy.

9.
Front Bioeng Biotechnol ; 12: 1390708, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952670

RESUMO

Introduction: Triple negative breast cancer (TNBC), a highly aggressive subtype accounting for 15-20% of all breast cancer cases, faces limited treatment options often accompanied by severe side effects. In recent years, natural extracellular nanovesicles derived from plants have emerged as promising candidates for cancer therapy, given their safety profile marked by non-immunogenicity and absence of inflammatory responses. Nevertheless, the potential anti-cancer effects of Citrus limon L.-derived extracellular nanovesicles (CLENs) for breast cancer treatment is still unexplored. Methods: In this study, we investigated the anti-cancer effects of CLENs on two TNBC cell lines (4T1 and HCC-1806 cells) under growth conditions in 2D and 3D culture environments. The cellular uptake efficiency of CLENs and their internalization mechanism were evaluated in both cells using confocal microscopy. Thereafter, we assessed the effect of different concentrations of CLENs on cell viability over time using a dual approach of Calcein-AM PI live-dead assay and CellTiter-Glo bioluminescence assay. We also examined the influence of CLENs on the migratory and evasion abilities of TNBC cells through wound healing and 3D Matrigel drop evasion assays. Furthermore, Western blot analysis was employed to investigate the effects of CLENs on the phosphorylation levels of phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), and extracellular signal- regulated kinase (ERK) expression. Results: We found that CLENs were internalized by the cells via endocytosis, leading to decreased cell viability, in a dose- and time-dependent manner. Additionally, the migration and evasion abilities of TNBC cells were significantly inhibited under exposed to 40 and 80 µg/mL CLENs. Furthermore, down-regulated expression levels of phosphorylated phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), and extracellular signal-regulated kinase (ERK), suggesting that the inhibition of cancer cell proliferation, migration, and evasion is driven by the inhibition of the PI3K/AKT and MAPK/ERK signaling pathways. Discussion: Overall, our results demonstrate the anti-tumor efficiency of CLENs against TNBC cells, highlighting their potential as promising natural anti-cancer agents for clinical applications in cancer treatment.

10.
Nanoscale ; 16(35): 16671-16683, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39171675

RESUMO

Pollution from micro- and nanoplastics (MNPs) has long been a topic of concern due to its potential impact on human health. MNPs can circulate through human blood and, thus far, have been found in the lungs, spleen, stomach, liver, kidneys and even in the brain, placenta, and breast milk. While data are already available on the adverse biological effects of pristine MNPs (e.g. oxidative stress, inflammation, cytotoxicity, and even cancer induction), no report thus far clarified whether the same effects are modulated by the formation of a protein corona around MNPs. To this end, here we use pristine and human-plasma pre-coated polystyrene (PS) nanoparticles (NPs) and investigate them in cultured breast cancer cells both in terms of internalization and cell biochemical response to the exposure. It is found that pristine NPs tend to stick to the cell membrane and inhibit HER-2-driven signaling pathways, including phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathways, which are associated with cancer cell survival and growth. By contrast, the formation of a protein corona around the same NPs can promote their uptake by endocytic vesicles and final sequestration within lysosomes. Of note is that such intracellular fate of PS-NPs is associated with mitigation of the biochemical alterations of the phosphorylated AKT (pAKT)/AKT and phosphorylated ERK (pERK)/ERK levels. These findings provide the distribution of NPs in human breast cancer cells, may broaden our understanding of the interactions between NPs and breast cancer cells and underscore the crucial role of the protein corona in modulating the impact of MNPs on human health.


Assuntos
Neoplasias da Mama , Poliestirenos , Coroa de Proteína , Humanos , Coroa de Proteína/química , Coroa de Proteína/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/tratamento farmacológico , Feminino , Poliestirenos/química , Microplásticos/química , Linhagem Celular Tumoral , Nanopartículas/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células MCF-7 , Sobrevivência Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
11.
ACS Omega ; 9(32): 34624-34635, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39157118

RESUMO

Currently available vaccines against COVID-19 showed high efficacy against the original strain of SARS-CoV-2 but progressively lower efficacy against new variants. In response to emerging SARS-CoV-2 strains, we propose chimeric DNA vaccines encoding the spike antigen, including a combination of selected key mutations from different variants of concern. We developed two DNA vaccines, pVAX-S1-TM-D614G and pVAX-S1-TM-INDUK (INDUK), encoding the SARS-CoV-2 S1 spike subunit in fusion with the transmembrane region that allows protein trimerization as predicted by in silico analysis. pVAX-S1-TM-D614G included the dominant D614G substitution, while the chimeric vaccine INDUK contained additional selected mutations from the Delta (E484Q and L452R) and Alpha (N501Y and A570D) variants. Considering that aging is a risk factor for severe disease and that suboptimal vaccine responses were observed in older individuals, the immunogenicity of pVAX-S1-TM-D614G and INDUK was tested in both young and aged C57BL/6 mice. Two vaccine doses were able to trigger significant anti-SARS-CoV-2 antibody production, showing neutralizing activity. ELISA tests confirmed that antibodies induced by pVAX-S1-TM-D614G and INDUK were able to recognize both Wuhan Spike and Delta variant Spike as trimers, while neutralizing antibodies were detected by an ACE2:SARS-CoV-2 Spike S1 inhibitor screening assay, designed to assess the capacity of antibodies to block the interaction between the viral spike S1 protein and the ACE2 receptor. Although antibody titer declined within six months, a third booster dose significantly increased the magnitude of humoral response, even in aged individuals, suggesting that immune recall can improve antibody response durability. The analysis of cellular responses demonstrated that vaccination with INDUK elicited an increase in the percentage of SARS-CoV-2-specific IFN-γ producing T lymphocytes in immunized young mice and TNF-α-producing T lymphocytes in both young and aged mice. These findings not only hold immediate promise for addressing evolving challenges in SARS-CoV-2 vaccination but also open avenues to refine strategies and elevate the effectiveness of next-generation vaccines.

12.
Toxicol In Vitro ; 91: 105632, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37329963

RESUMO

Plastic pollution poses a significant threat to both ecosystems and human health, as fragments of microscale size are daily inhaled and ingested. Such tiny specks are defined as microplastics (MPs), and although their presence as environmental contaminants is ubiquitous in the world, their possible effects at biological and physiological levels are still not clear. To explore the potential impacts of MP exposure, we produced and characterized polyethylene terephthalate (PET) micro-fragments, then administered them to living cells. PET is widely employed in the production of plastic bottles, and thus represents a potential source of environmental MPs. However, its potential effects on public health are hardly investigated, as the current bio-medical research on MPs mainly utilizes different models, such as polystyrene particles. This study employed cell viability assays and Western blot analysis to demonstrate cell-dependent and dose-dependent cytotoxic effects of PET MPs, as well as a significant impact on HER-2-driven signaling pathways. Our findings provide insight into the biological effects of MP exposure, particularly for a widely used but poorly investigated material such as PET.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Microplásticos/toxicidade , Plásticos/toxicidade , Polietilenotereftalatos/toxicidade , Ecossistema , Poliestirenos/toxicidade , Poluentes Químicos da Água/toxicidade , Monitoramento Ambiental
13.
Biomolecules ; 12(1)2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-35053228

RESUMO

Breast cancers (BCs) may present dramatic diagnoses, both for ineffective therapies and for the limited outcomes in terms of lifespan. For these types of tumors, the search for new drugs is a primary necessity. It is widely recognized that gold compounds are highly active and extremely potent as anticancer agents against many cancer cell lines. The presence of the metal plays an essential role in the activation of the cytotoxicity of these coordination compounds, whose activity, if restricted to the ligands alone, would be non-existent. On the other hand, gold exhibits a complex biochemistry, substantially variable depending on the chemical environments around the central metal. In this review, the scientific findings of the last 6-7 years on two classes of gold(I) compounds, containing phosphane or carbene ligands, are reviewed. In addition to this class of Au(I) compounds, the recent developments in the application of Auranofin in regards to BCs are reported. Auranofin is a triethylphosphine-thiosugar compound that, being a drug approved by the FDA-therefore extensively studied-is an interesting lead gold compound and a good comparison to understand the activities of structurally related Au(I) compounds.


Assuntos
Antineoplásicos , Auranofina , Neoplasias da Mama , Ouro , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Auranofina/química , Auranofina/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Feminino , Ouro/química , Ouro/uso terapêutico , Humanos , Relação Estrutura-Atividade
14.
Nanoscale Adv ; 4(18): 4009-4015, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36133348

RESUMO

In the last decade, graphene oxide (GO)-based nanomaterials have attracted much attention for their potential anti-cancer properties against various cancer cell types. However, while in vitro studies are promising, following in vivo investigations fail to show any relevant efficacy. Recent research has clarified that the wide gap between benchtop discoveries and clinical practice is due to our limited knowledge about the physical-chemical transformation of nanomaterials in vivo. In physiological environments, nanomaterials are quickly coated by a complex dress of biological molecules referred to as the protein corona. Mediating the interaction between the pristine material and the biological system the protein corona controls the mechanisms of action of nanomaterials up to the sub-cellular level. Here we investigate the anticancer ability of GO in SK-BR-3 human breast cancer cells over-expressing the human epidermal growth factor receptor 2 (HER-2), which is functionally implicated in the cell growth and proliferation through the activation of downstream pathways, including the PI3K/AKT/mTOR and MAPK/ERK signaling cascades. Western blot analysis demonstrated that GO treatment resulted in a marked decrease in total HER-2, associated with a down-regulation of the expression and activation of protein kinase B (AKT) and extracellular signal-regulated kinase (ERK) thus indicating that GO may act as a potent HER-2 inhibitor. On the other side, the protein corona reverted the effects of GO on HER-2 expression and molecular downstream events to the control level. Our findings may suggest a mechanistic explanation of the reduced anticancer properties of GO-based nanomaterials in vivo. These results may also represent a good prediction strategy for the anticancer activity of nanomaterials designed for biomedical purposes, reaffirming the necessity of exploring their effectiveness under physiologically relevant conditions before moving on to the next in vivo studies.

15.
ACS Appl Mater Interfaces ; 14(51): 56666-56677, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36524967

RESUMO

Lipid nanoparticles (LNPs) are currently having an increasing impact on nanomedicines as delivery agents, among others, of RNA molecules (e.g., short interfering RNA for the treatment of hereditary diseases or messenger RNA for the development of COVID-19 vaccines). Despite this, the delivery of plasmid DNA (pDNA) by LNPs in preclinical studies is still unsatisfactory, mainly due to the lack of systematic structural and functional studies on DNA-loaded LNPs. To tackle this issue, we developed, characterized, and tested a library of 16 multicomponent DNA-loaded LNPs which were prepared by microfluidics and differed in lipid composition, surface functionalization, and manufacturing factors. 8 out of 16 formulations exhibited proper size and zeta potential and passed to the validation step, that is, the simultaneous quantification of transfection efficiency and cell viability in human embryonic kidney cells (HEK-293). The most efficient formulation (LNP15) was then successfully validated both in vitro, in an immortalized adult keratinocyte cell line (HaCaT) and in an epidermoid cervical cancer cell line (CaSki), and in vivo as a nanocarrier to deliver a cancer vaccine against the benchmark target tyrosine-kinase receptor HER2 in C57BL/6 mice. Finally, by a combination of confocal microscopy, transmission electron microscopy and synchrotron small-angle X-ray scattering, we were able to show that the superior efficiency of LNP15 can be linked to its disordered nanostructure consisting of small-size unoriented layers of pDNA sandwiched between closely apposed lipid membranes that undergo massive destabilization upon interaction with cellular lipids. Our results provide new insights into the structure-activity relationship of pDNA-loaded LNPs and pave the way to the clinical translation of this gene delivery technology.


Assuntos
COVID-19 , Nanopartículas , Animais , Camundongos , Humanos , Vacinas contra COVID-19 , Células HEK293 , Lipídeos/química , Camundongos Endogâmicos C57BL , DNA/química , Nanopartículas/química , RNA Interferente Pequeno
16.
Pharmaceutics ; 14(8)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36015328

RESUMO

DNA vaccination has been extensively studied as a promising strategy for tumor treatment. Despite the efforts, the therapeutic efficacy of DNA vaccines has been limited by their intrinsic poor cellular internalization. Electroporation, which is based on the application of a controlled electric field to enhance DNA penetration into cells, has been the method of choice to produce acceptable levels of gene transfer in vivo. However, this method may cause cell damage or rupture, non-specific targeting, and even degradation of pDNA. Skin irritation, muscle contractions, pain, alterations in skin structure, and irreversible cell damage have been frequently reported. To overcome these limitations, in this work, we use a microfluidic platform to generate DNA-loaded lipid nanoparticles (LNPs) which are then characterized by a combination of dynamic light scattering (DLS), synchrotron small-angle X-ray scattering (SAXS), and transmission electron microscopy (TEM). Despite the clinical successes obtained by LNPs for mRNA and siRNA delivery, little is known about LNPs encapsulating bulkier DNA molecules, the clinical application of which remains challenging. For in vitro screening, LNPs were administered to human embryonic kidney 293 (HEK-293) and Chinese hamster ovary (CHO) cell lines and ranked for their transfection efficiency (TE) and cytotoxicity. The LNP formulation exhibiting the highest TE and the lowest cytotoxicity was then tested for the delivery of the DNA vaccine pVAX-hECTM targeting the human neoantigen HER2, an oncoprotein overexpressed in several cancer types. Using fluorescence-activated cell sorting (FACS), immunofluorescence assays and fluorescence confocal microscopy (FCS), we proved that pVAX-hECTM-loaded LNPs produce massive expression of the HER2 antigen on the cell membrane of HEK-293 cells. Our results provide new insights into the structure-activity relationship of DNA-loaded LNPs and pave the way for the access of this gene delivery technology to preclinical studies.

17.
Cancers (Basel) ; 14(16)2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36011047

RESUMO

The advent of trastuzumab has significantly improved the prognosis of HER2-positive (HER2+) breast cancer patients; nevertheless, drug resistance limits its clinical benefit. Anti-HER2 active immunotherapy represents an attractive alternative strategy, but effective immunization needs to overcome the patient's immune tolerance against the self-HER2. Phage display technology, taking advantage of phage intrinsic immunogenicity, permits one to generate effective cancer vaccines able to break immune tolerance to self-antigens. In this study, we demonstrate that both preventive and therapeutic vaccination with M13 bacteriophages, displaying the extracellular (EC) and transmembrane (TM) domains of human HER2 or its Δ16HER2 splice variant on their surface (ECTM and Δ16ECTM phages), delayed mammary tumor onset and reduced tumor growth rate and multiplicity in ∆16HER2 transgenic mice, which are tolerant to human ∆16HER2. This antitumor protection correlated with anti-HER2 antibody production. The molecular mechanisms underlying the anticancer effect of vaccine-elicited anti-HER2 antibodies were analyzed in vitro against BT-474 human breast cancer cells, sensitive or resistant to trastuzumab. Immunoglobulins (IgG) purified from immune sera reduced cell viability mainly by impairing ERK phosphorylation and reactivating retinoblastoma protein function in both trastuzumab-sensitive and -resistant BT-474 cells. In conclusion, we demonstrated that phage-based HER2 vaccines impair mammary cancer onset and progression, opening new perspectives for HER2+ breast cancer treatment.

18.
ACS Appl Mater Interfaces ; 13(4): 5574-5582, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33472372

RESUMO

Soft actuators with perception capability are essential for robots to intelligently interact with humans and the environment. However, existing perceptive soft actuators require complex integration and coupling between the discrete functional units to achieve autonomy. Here, we report entirely soft actuators with embodied sensing, actuation, and control at the single-unit level. This is achieved by synergistically harnessing the mechanosensing and electrothermal properties of liquid metal (LM) to actuate the thermally responsive liquid crystal elastomer (LCE). We create multifunctional LM circuits on the LCE surface using a simple and facile methodology based on magnetic printing. The fluidic LM circuit can not only be utilized as a conformable resistive heater but also as a sensory skin to perceive its own deformation. Moreover, the rational design of the LM circuits makes it possible to achieve biomimetic autonomous actuation in response to mechanical stimuli such as pressure or strain. In addition, the intrinsic stretchability of LM allows us to create 3D spring-like actuators via a simple prestretch step, and complex helical motions can be obtained upon mechanical stimulation. This work provides a unique and simple design for autonomous soft robotics with embodied intelligence.

19.
ACS Appl Mater Interfaces ; 13(33): 39915-39924, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34396781

RESUMO

Architected metallic materials generally suffer from a serious engineering problem of mechanical instability manifested as the emergence of localized deformation bands and collapse of strength. They usually cannot exhibit satisfactory shape recoverability due to the little recoverable strain of metallic constituent material. After yielding, the metallic constituent material usually exhibits a continuous low strain-hardening capacity, giving the local yielded regions of architecture low load resistance and easily developing into excessive deformation bands, accompanied by the collapse of strength. Here, a novel constituent material deformation design strategy has been skillfully proposed, where the low load resistance of yielded regions of the architecture can be effectively compensated by the significant self-strengthening behavior of constituent material, thus avoiding the formation of localized deformation bands and collapse of strength. To substantiate this strategy, shape-memory alloys (SMAs) are considered as suitable constituent materials for possessing both self-strengthening behavior and shape-recovery function. A 3D-printing technique was adopted to prepare various NiTi SMA architected materials with different geometric structures. It is demonstrated that all of these architected metallic materials can be stably and uniformly compressed by up to 80% without the formation of localized bands, collapse of strength, and structural failure, exhibiting ultrahigh damage tolerance. Furthermore, these SMA architected materials can display more than 98% shape recovery even after 80% deformation and excellent cycle stability during 15 cycles. This work exploits the amazing impact of constituent materials on constructing supernormal properties of architected materials and will open new avenues for developing high-performance architected metallic materials.

20.
Pharmaceutics ; 13(8)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34452253

RESUMO

In recent years, lipid nanoparticles (LNPs) have gained considerable attention in numerous research fields ranging from gene therapy to cancer immunotherapy and DNA vaccination. While some RNA-encapsulating LNP formulations passed clinical trials, DNA-loaded LNPs have been only marginally explored so far. To fulfil this gap, herein we investigated the effect of several factors influencing the microfluidic formulation and transfection behavior of DNA-loaded LNPs such as PEGylation, total flow rate (TFR), concentration and particle density at the cell surface. We show that PEGylation and post-synthesis sample concentration facilitated formulation of homogeneous and small size LNPs with high transfection efficiency and minor, if any, cytotoxicity on human Embryonic Kidney293 (HEK-293), spontaneously immortalized human keratinocytes (HaCaT), immortalized keratinocytes (N/TERT) generated from the transduction of human primary keratinocytes, and epidermoid cervical cancer (CaSki) cell lines. On the other side, increasing TFR had a detrimental effect both on the physicochemical properties and transfection properties of LNPs. Lastly, the effect of particle concentration at the cell surface on the transfection efficiency (TE) and cell viability was largely dependent on the cell line, suggesting that its case-by-case optimization would be necessary. Overall, we demonstrate that fine tuning formulation and microfluidic parameters is a vital step for the generation of highly efficient DNA-loaded LNPs.

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