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1.
J Clin Exp Hepatol ; 14(5): 101410, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716375

RESUMO

Background: Gallbladder cancer (GBC) is a biologically aggressive malignancy requiring appropriate biomarkers to improve its outcome. Role of ABC transporters (ABCB1 and ABCG2) has been linked to cancer aggressiveness, tumorigenesis and multidrug resistance. Herein, we studied the prognostic implication of ABCB1 and ABCG2 in GBC. Methods: Fresh tissue (tumour & normal) samples collected from 54 patients who underwent R0 resection, were analysed for mRNA and protein expression of ABCB1 and ABCG2 by quantitative Real-Time PCR and western blotting, respectively, in this prospective study. The molecular findings were correlated with clinical-pathological parameters using χ2 and fisher exact test. The molecular changes in ABCB1 and ABCG2 were analysed for predicting overall survival (OS), disease-free survival (DFS) and response to chemotherapy using Kaplan-Meier log-rank test and Cox regression multivariate analysis. Results: The mean age of the cohort was 50 ± 13.2 with 26 (48.1%) in patients having early stage gallbladder cancer (GBC). Over-expression of ABCB1 and ABCG2 was noted in 32/54 (59%) and 40/54 (74%) cases, respectively. The protein expression of ABCB1(P-glycoprotein) and ABCG2 (BCRP) was higher in 27/54 (50%) and 37/54 (59%) cases, respectively. The mean OS and DFS was 20.7 ± 11.5 and 19.3 ± 12.2 months at median follow-up of 24 months. The TNM stage, lymph node metastasis, and presence of gallstone were significant factors for predicting OS and DFS on multivariate analysis. Both ABCB1 and ABCG2 did not show any significant correlation with OS and DFS with similar incidences of late death and recurrence among over-expression and down-expression. Sub-group comparison suggests that change in expression pattern of ABCB1 and ABCG2 may not affect response to chemotherapy in GBC. Conclusion: Altered expression of ABCB1 and ABCG2 may not be a useful prognostic marker for survival or response to chemotherapy in GBC. Presently, histo-pathological characteristics and associated gallstones are the important predictors for survival and recurrence in GBC.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38509420

RESUMO

With the advent of nanotechnology, the treatment of cancer is changing from a conventional to a nanoparticle-based approach. Thus, developing nanoparticles to treat cancer is an area of immense importance. We prepared silver nanoparticles (AgNPs) from methanolic extract of Alpinia galanga rhizome and characterized them by UV-Vis spectrophotometry, Fourier transform Infrared (FTIR) spectroscopy, Zetasizer, and Transmission electron Microscopy (TEM). UV-Vis spectrophotometry absorption spectrum showed surface plasmon between 400 and 480 nm. FTIR spectrum analysis implies that various phytochemicals/secondary metabolites are involved in the reduction, caping, and stabilization of AgNPs. The Zetasier result suggests that the particles formed are small in size with a low polydispersity index (PDI), suggesting a narrow range of particle distribution. The TEM image suggests that the particles formed are mostly of spherical morphology with nearly 20-25 nm. Further, the selected area electron diffraction (SAED) image showed five electron diffraction rings, suggesting the polycrystalline nature of the particles. The nanoparticles showed high anticancer efficacy against cervical cancer (SiHa) cell lines. The nanostructures showed dose-dependent inhibition with 40% killing observed at 6.25 µg/mL dose. The study showed an eco-friendly and cost-effective approach to the synthesis of AgNPs and provided insight into the development of antioxidant and anticancer agents.

3.
Ageing Res Rev ; 87: 101906, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36905963

RESUMO

Growing neurological diseases pose difficult challenges for modern medicine to diagnose and manage them effectively. Many neurological disorders mainly occur due to genetic alteration in genes encoding mitochondrial proteins. Moreover, mitochondrial genes exhibit a higher rate of mutation due to the generation of Reactive oxygen species (ROS) during oxidative phosphorylation operating in their vicinity. Among the different complexes of Electron transport chain (ETC), NADH: Ubiquinone oxidoreductase (Mitochondrial complex I) is the most important. This multimeric enzyme, composed of 44 subunits, is encoded by both nuclear and mitochondrial genes. It often exhibits mutations resulting in development of various neurological diseases. The most prominent diseases include leigh syndrome (LS), leber hereditary optic neuropathy (LHON), mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS), myoclonic epilepsy associated with ragged-red fibers (MERRF), idiopathic Parkinson's disease (PD) and, Alzheimer's disease (AD). Preliminary data suggest that mitochondrial complex I subunit genes mutated are frequently of nuclear origin; however, most of the mtDNA gene encoding subunits are also primarily involved. In this review, we have discussed the genetic origins of neurological disorders involving mitochondrial complex I and signified recent approaches to unravel the diagnostic and therapeutic potentials and their management.


Assuntos
Complexo I de Transporte de Elétrons , Encefalomiopatias Mitocondriais , Humanos , Complexo I de Transporte de Elétrons/genética , Relevância Clínica , Mitocôndrias/genética , DNA Mitocondrial/genética , Encefalomiopatias Mitocondriais/genética , Mutação
4.
J Cancer Res Clin Oncol ; 149(1): 441-465, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36572792

RESUMO

BACKGROUND: Colorectal cancer (CRC) is the third most common cancer with a significant impact on loss of life. In 2020, nearly 1.9 million new cases and over 9,35,000 deaths were reported. Numerous microbes that are abundant in the human gut benefit host physiology in many ways. Although the underlying mechanism is still unknown, their association appears to be crucial in the beginning and progression of CRC. Diet has a significant impact on the microbial composition and may increase the chance of getting CRC. Increasing evidence points to the gut microbiota as the primary initiator of colonic inflammation, which is connected to the development of colonic tumors. However, it is unclear how the microbiota contributes to the development of CRCs. Patients with CRC have been found to have dysbiosis of the gut microbiota, which can be identified by a decline in commensal bacterial species, such as those that produce butyrate, and a concurrent increase in harmful bacterial populations, such as opportunistic pathogens that produce pro-inflammatory cytokines. We believe that using probiotics or altering the gut microbiota will likely be effective tools in the fight against CRC treatment. PURPOSE: In this review, we revisited the association between gut microbiota and colorectal cancer whether cause or effect. The various factors which influence gut microbiome in patients with CRC and possible mechanism in relation with development of CRC. CONCLUSION: The clinical significance of the intestinal microbiota may aid in the prevention and management of CRC.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Microbiota , Probióticos , Humanos , Microbioma Gastrointestinal/fisiologia , Neoplasias Colorretais/patologia , Probióticos/uso terapêutico
5.
Clin Chim Acta ; 537: 60-73, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36244434

RESUMO

Cancer remains the second leading cause of death worldwide and newly diagnosed cases have increased at an alarming rate. One in every four people has a lifetime risk of being afflicted with cancer. Early diagnosis, which is essential in reducing morbidity and mortality, requires the development of highly sensitive and specific techniques to identify and monitor molecular changes for cancer-specific genetic and epigenetic markers. Among these, fluorescent in situ hybridization (FISH), Polymerase Chain Reaction (PCR), DNA microarray and NanoString technologies are notable. Recent advances in the development of efficient and cost-effective next-generation sequencing (NGS) has enabled whole genome, exome and transcriptome analysis. This review focuses on the features and applications of important molecular techniques to detect various genetic mutations thus enabling improved diagnosis, treatment and outcome.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias , Humanos , Hibridização in Situ Fluorescente , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Exoma , Neoplasias/diagnóstico , Neoplasias/genética , Mutação
6.
Crit Rev Oncol Hematol ; 180: 103850, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36261117

RESUMO

Oral or mouth cancer is the 16th most common form of cancer among the world's topmost malignancies. Healthy lifestyle and control of known risk factors can reduce its incidences further. Patients succumb to oral cancer when diagnosed late and lack timely access to tertiary care. Molecular biomarkers might help in early detection of oral cancer. Recently, researchers have identified numerous microRNAs which play a crucial role in promoting and suppressing oral cancers. miRNAs are short non-coding RNA molecules (18-22 nucleotides) that play a pivotal role in regulating gene expression. Understanding the miRNA interplays in oral cancers could augment the development of potential diagnostic, prognostic, and therapeutic tools. Liquid biopsy- a non-invasive approach that has been used lately, allows the determination of miRNAs in biological fluids that play essential roles in tumor suppression and cancer promotion. Herein, we summarize an update on the role of miRNAs in the diagnosis and treatment of oral cancer.


Assuntos
MicroRNAs , Neoplasias Bucais , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Detecção Precoce de Câncer , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/genética , Neoplasias Bucais/terapia , Prognóstico , Regulação Neoplásica da Expressão Gênica
7.
Cell Signal ; 99: 110413, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35907519

RESUMO

Colorectal cancer (CRC) is the third most common cancer with the second most frequent cause of death worldwide. One fourth to one fifth of the CRC cases are detected at advance stage. Early detection of colorectal cancer might help in decreasing mortality and morbidity worldwide. CRC being a heterogeneous disease, new non-invasive approaches are needed to complement and improve the screening and management of CRC. Reliable and early detectable biomarkers would improve diagnosis, prognosis, therapeutic responses, and will enable the prediction of drug response and recurrence risk. Over the past decades molecular research has demonstrated the potentials of CTCs, ctDNAs, circulating mRNAs, ncRNAs, and exosomes as tumor biomarkers. Non-invasive screening approaches using fecal samples for identification of altered gut microbes in CRC is also gaining attention. Exosomes can be potential candidates that can be employed in the drug delivery system. Further, the integration of in vitro, in vivo and in silico models that involve CRC biomarkers will help to understand the interactions occurring at the cellular level. This review summarizes recent update on CRC biomarkers and their application along with the nanoparticles followed by the application of organoid culture in CRC.


Assuntos
Neoplasias Colorretais , Exossomos , Biomarcadores Tumorais , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Sistemas de Liberação de Medicamentos , Humanos , Prognóstico
8.
Clin Chim Acta ; 532: 95-114, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35667477

RESUMO

Cancer remains a common health issue having significant socioeconomic burden worldwide. Despite the awareness campaigns, cancer cases continue to increase due to an aging population and lack of early detection biomarkers. Accordingly, much research has focused on non-traditional approaches which include novel imaging modalities and liquid biopsy. In addition, a considerable number of biomacromolecules as well as other biomarkers have been identified to further explore their potential use as diagnostic, prognostic and therapeutic tools. In this review, we provide an update on these new findings and explore their clinical application in cancer.


Assuntos
Células Neoplásicas Circulantes , Idoso , Biomarcadores Tumorais , Humanos , Biópsia Líquida , Células Neoplásicas Circulantes/patologia , Prognóstico
9.
Molecules ; 27(3)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35164370

RESUMO

Fibrin-based systems offer promises in drug and gene delivery as well as tissue engineering. We established earlier a fibrin-based plasma beads (PB) system as an efficient carrier of drugs and antigens. In the present work, attempts were made to further improve its therapeutic efficacy exploiting innovative ideas, including the use of plasma alginate composite matrices, proteolytic inhibitors, cross linkers, and dual entrapment in various liposomal formulations. In vitro efficacy of the different formulations was examined. Pharmacokinetics of the formulations encapsulating Amphotericin B (AmpB), an antifungal compound, were investigated in Swiss albino mice. While administration of the free AmpB led to its rapid elimination (<72 h), PB/liposome-PB systems were significantly effective in sustaining AmpB release in the circulation (>144 h) and its gradual accumulation in the vital organs, also compared to the liposomal formulations alone. Interestingly, the slow release of AmpB from PB was unusual compared to other small molecules in our earlier findings, suggesting strong interaction with plasma proteins. Molecular interaction studies of bovine serum albumin constituting approximately 60% of plasma with AmpB using isothermal titration calorimetry and in silico docking verify these interactions, explaining the slow release of AmpB entrapped in PB alone. The above findings suggest that PB/liposome-PB could be used as safe and effective delivery systems to combat fungal infections in humans.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Sistemas de Liberação de Medicamentos , Fungos/efeitos dos fármacos , Lipossomos/administração & dosagem , Micoses/tratamento farmacológico , Plasma/química , Alginatos/química , Anfotericina B/química , Animais , Antifúngicos/química , Feminino , Lipossomos/química , Camundongos , Coelhos
10.
J Control Release ; 342: 1-13, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34864116

RESUMO

The efficacy of oral insulin drug delivery is seriously hampered by multiple gastrointestinal barriers, especially transepithelial barriers, including apical endocytosis, lysosomal degradation, cytosolic diffusion and basolateral exocytosis. In this study, a functional nanoparticle (PG-FAPEP) with dual-modification was constructed to sequentially address these important absorption obstacles for improved oral insulin delivery. The dual surface decorations folate and charge-convertible tripeptide endowed PG-FAPEP with the ability to target the apical and basolateral sides of enterocytes, respectively. After fast diffusion across the mucus layer, PG-FAPEP could be efficiently internalized into epithelial cells via a folate receptor-mediated pathway and subsequently became positively charged in acidic lysosomes due to the surface tripeptide, triggering the proton sponge effect to escape lysosomes. When entering the cytosolic medium, PG-FAPEP was converted to neutral charge again, attenuating intracellular adhesion, and gained improved motility toward the basolateral side. Finally, the tripeptide helped PG-FAPEP recognize the proton-coupled oligopeptide transporter (PHT1) in the basolateral membrane, boosting intact exocytosis across intestinal epithelial cells. The in vivo studies further verified that PG-FAPEP could traverse the intestinal epithelium by folate receptor-mediated endocytosis, lysosomal escape, and PHT1-mediated exocytosis, exhibiting a high oral insulin bioavailability of 14.3% and a prolonged hypoglycemic effect. This formulation addresses multiple absorption barriers on demand with a simple dual-modification strategy. Therefore, these features allow PG-FAPEP to unleash the potential of oral macromolecule delivery.


Assuntos
Insulina , Nanopartículas , Administração Oral , Células CACO-2 , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Absorção Intestinal , Nanopartículas/química
11.
Cell Signal ; 86: 110080, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34245863

RESUMO

Sphingosine-1-Phosphate (S1P) plays an important role in normal physiology, inflammation, initiation and progression of cancer. Deregulation of S1P signaling causes aberrant proliferation, affects survival, leads to angiogenesis and metastasis. Sphingolipid rheostat is crucial for cellular homeostasis. Discrepancy in sphingolipid metabolism is linked to cancer and drug insensitivity. Owing to these diverse functions and being a potent mediator of tumor growth, S1P signaling might be a suitable candidate for anti-tumor therapy or combination therapy. In this review, with a focus on colorectal cancer we have summarized the interacting partners of S1P signaling pathway, its therapeutic approaches along with the contribution of S1P signaling to various cancer hallmarks.


Assuntos
Neoplasias Colorretais , Lisofosfolipídeos , Humanos , Lisofosfolipídeos/metabolismo , Transdução de Sinais , Esfingosina/análogos & derivados , Esfingosina/metabolismo
12.
Crit Rev Oncol Hematol ; 162: 103348, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33961993

RESUMO

The asymptomatic behaviour of esophageal cancerous cells at early stages develops advanced clinical presentation of the disease, resulting in poor prognosis and curbed intervention of therapeutic modalities. The endeavours to detect diagnostic and prognostic markers have been proven futile at the clinical platform. While several biomarkers have been investigated, including CYFRA 21-1, carcinoembryonic antigen and squamous cell carcinoma antigen, their sensitivity has not proved consistently satisfactory across the various stages of esophageal cancer. Hence, there is an impending requirement of biomarkers for early diagnosis and better prognosis. In the recent past, next generation sequencing (NGS) tool has emerged as an important tool to highlight the hallmarks of esophageal cancer (EC). This review summarizes the changes/mutations occurred in tumor cells during carcinogenesis and addresses the contribution of NGS techniques, viz. whole genome sequencing (WGS), RNA-Sequencing and Exome sequencing (ES), in EC. Additionally, this review highlights the connection between the findings from these techniques. An effort has been made to emphasize the genes affected and involved signaling pathway in EC. Further, investigations of these mutated genes would not only shed light on the relevant genes to be studied but also help in the better management and cure through personalized therapy.


Assuntos
Neoplasias Esofágicas , Sequenciamento de Nucleotídeos em Larga Escala , Antígenos de Neoplasias , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Genômica , Humanos , Queratina-19 , Mutação , Prognóstico
13.
Pharmacol Res ; 167: 105544, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33722711

RESUMO

Cancer is one of the major global health problems, responsible for the second-highest number of deaths. The genetic and epigenetic changes in the oncogenes or tumor suppressor genes alter the regulatory pathways leading to its onset and progression. Conventional methods are used in appropriate combinations for the treatment. Surgery effectively treats localized tumors; however, it fails to treat metastatic tumors, leading to a spread in other organs, causing a high recurrence rate and death. Among the different strategies, the nanocarriers-based approach is highly sought for, but its nonspecific delivery can cause a profound side effect on healthy cells. Targeted nanomedicine has the advantage of targeting cancer cells specifically by interacting with the receptors overexpressed on their surface, overcoming its non-specificity to target healthy cells. Nanocarriers prepared from biodegradable and biocompatible materials are decorated with different ligands by encapsulating therapeutic or diagnostic agents or both to target cancer cells overexpressing the receptors. Scientists are now utilizing a theranostic approach to simultaneously evaluate nanocarrier bio-distribution and its effect on the treatment regime. Herein, we have summarized the recent 5-year efforts in the development of the ligands decorated biodegradable nanocarriers, as a targeted nanomedicine approach, which has been highly promising in the treatment of cancer.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Nanoestruturas/química , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Humanos , Ligantes , Nanomedicina/métodos
14.
Acta Pharm Sin B ; 9(4): 858-870, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31384544

RESUMO

Recently, liposomes have been widely used in cancer therapeutics, but their anti-tumor effects are suboptimal due to limited tumor penetration. To solve this problem, researchers have made significant efforts to optimize liposomal diameters and potentials, but little attention has been paid to liposomal membrane rigidity. Herein, we sought to demonstrate the effects of cholesterol-tuned liposomal membrane rigidity on tumor penetration and anti-tumor effects. In this study, liposomes composed of hydrogenated soybean phospholipids (HSPC), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG2000) and different concentrations of cholesterol were prepared. It was revealed that liposomal membrane rigidity decreased with the addition of cholesterol. Moderate cholesterol content conferred excellent diffusivity to liposomes in simulated diffusion medium, while excessive cholesterol limited the diffusion process. We concluded that the differences of the diffusion rates likely stemmed from the alterations in liposomal membrane rigidity, with moderate rigidity leading to improved diffusion. Next, the in vitro tumor penetration and the in vivo anti-tumor effects were analyzed. The results showed that liposomes with moderate rigidity gained excellent tumor penetration and enhanced anti-tumor effects. These findings illustrate a feasible and effective way to improve tumor penetration and therapeutic efficacy of liposomes by changing the cholesterol content, and highlight the importance of liposomal membrane rigidity.

15.
ACS Nano ; 13(7): 7676-7689, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31187973

RESUMO

Small unilamellar vesicles (SUVs), ubiquitous in organisms, play key and active roles in various biological processes. Although the physical properties of the constituent lipid molecules (i.e., the acyl chain length and saturation) are known to affect the mechanical properties of SUVs and consequently regulate their biological behaviors and functions, the underlying mechanism remains elusive. Here, we combined theoretical modeling and experimental investigation to probe the mechanical behaviors of SUVs with different lipid compositions. The membrane bending rigidity of SUVs increased with increasing chain length and saturation, resulting in differences in the vesicle rigidity and deformable capacity. Furthermore, we tested the tumor delivery capacity of liposomes with low, intermediate, and high rigidity as typical models for SUVs. Interestingly, liposomes with intermediate rigidity exhibited better tumor extracellular matrix diffusion and multicellular spheroid (MCS) penetration and retention than that of their stiffer or softer counterparts, contributing to improved tumor suppression. Stiff SUVs had superior cellular internalization capacity but intermediate tumor delivery efficacy. Stimulated emission depletion microscopy directly showed that the optimal formulation was able to transform to a rod-like shape in MCSs, which stimulated fast transport in tumor tissues. In contrast, stiff liposomes hardly deformed, whereas soft liposomes changed their shape irregularly, which slowed their MCS penetration. Our findings introduce special perspectives from which to map the detailed mechanical properties of SUVs with different compositions, provide clues for understanding the biological functions of SUVs, and suggest that liposome mechanics may be a design parameter for enhancing drug delivery.


Assuntos
Antineoplásicos/farmacologia , Camptotecina/análogos & derivados , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Neoplasias Pancreáticas/tratamento farmacológico , Estresse Mecânico , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Camptotecina/química , Camptotecina/farmacologia , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lipossomos/sangue , Lipossomos/síntese química , Lipossomos/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Moleculares , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Imagem Óptica , Neoplasias Pancreáticas/patologia , Tamanho da Partícula , Propriedades de Superfície , Células Tumorais Cultivadas
16.
Proc Natl Acad Sci U S A ; 116(12): 5362-5369, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30837316

RESUMO

Lipid nanovesicles are widely present as transport vehicles in living organisms and can serve as efficient drug delivery vectors. It is known that the size and surface charge of nanovesicles can affect their diffusion behaviors in biological hydrogels such as mucus. However, how temperature effects, including those of both ambient temperature and phase transition temperature (Tm), influence vehicle transport across various biological barriers outside and inside the cell remains unclear. Here, we utilize a series of liposomes with different Tm as typical models of nanovesicles to examine their diffusion behavior in vitro in biological hydrogels. We observe that the liposomes gain optimal diffusivity when their Tm is around the ambient temperature, which signals a drastic change in the nanovesicle rigidity, and that liposomes with Tm around body temperature (i.e., ∼37 °C) exhibit enhanced cellular uptake in mucus-secreting epithelium and show significant improvement in oral insulin delivery efficacy in diabetic rats compared with those with higher or lower Tm Molecular-dynamics (MD) simulations and superresolution microscopy reveal a temperature- and rigidity-mediated rapid transport mechanism in which the liposomes frequently deform into an ellipsoidal shape near the phase transition temperature during diffusion in biological hydrogels. These findings enhance our understanding of the effect of temperature and rigidity on extracellular and intracellular functions of nanovesicles such as endosomes, exosomes, and argosomes, and suggest that matching Tm to ambient temperature could be a feasible way to design highly efficient nanovesicle-based drug delivery vectors.


Assuntos
Hidrogéis/administração & dosagem , Hidrogéis/química , Lipídeos/química , Nanopartículas/química , Animais , Transporte Biológico/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Difusão/efeitos dos fármacos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Epitélio/metabolismo , Insulina/administração & dosagem , Insulina/química , Lipossomos/química , Masculino , Transição de Fase/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Temperatura
17.
Acta Pharm Sin B ; 9(1): 107-117, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30766782

RESUMO

Increasing the degree of supersaturation of drugs and maintaining their proper stability are very important in improving the oral bioavailability of poorly soluble drugs by a supersaturated drug delivery system (SDDS). In this study, we reported a complex system of Soluplus-Copovidone (Soluplus-PVPVA) loaded with the model drug silybin (SLB) that could not only maintain the stability of a supersaturated solution but also effectively promote oral absorption. The antiprecipitation effect of the polymers on SLB was observed using the solvent-shift method. In addition, the effects of the polymers on absorption were detected by cellular uptake and transport experiments. The mechanisms by which the Soluplus-PVPVA complex promotes oral absorption were explored by dynamic light scattering, transmission electron microscopy, fluorescence spectra and isothermal titration calorimetry analyses. Furthermore, a pharmacokinetic study in rats was used to demonstrate the advantages of the Soluplus-PVPVA complex. The results showed that Soluplus and PVPVA spontaneously formed complexes in aqueous solution via the adsorption of PVPVA on the hydrophilic-hydrophobic interface of the Soluplus micelle, and the Soluplus-PVPVA complex significantly increased the absorption of SLB. In conclusion, the Soluplus-PVPVA complex is a potential SDDS for improving the bioavailability of hydrophobic drugs.

18.
Biomed Pharmacother ; 107: 34-43, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30077836

RESUMO

Liposomes have established themselves as great pharmaceutical carriers over the past three decades. These phospholipid vesicular systems have undergone great technical advances including remote drug loading, targeted delivery, and combinatorial drug therapy. Ionic gradient liposomes (IGL) necessitates active loading of the drug in preformed vesicles exhibiting a transmembrane pH or ion gradient, with a low intra liposome pH (∼ 4-5), and a high outside pH (∼7-8). It allows high drug encapsulation and prolonged release, particularly for amphipathic weak acids and weak bases. Most local anesthetics (Bupivacaine, Ropivacaine, Tetracaine, and others) have a pka in the range of 7-9, which makes them ideal candidates for their entrapment in IGL. The same is true for most anthracyclines which have great anti-tumor properties (Doxorubicin, Daunorubicin, Idarubicin, and others). Many FDA approved liposomal drugs utilise ion gradient for their encapsulation. Considering their immense utility, we summarize here in this review, the recent contributions made by various research groups utilizing IGL, to accentuate the development of these carriers in drug delivery. This would possibly be helpful in carrying new investigations and further contributions in the optimization and advancements of new drugs for better therapeutics.


Assuntos
Anestésicos Locais/farmacologia , Antineoplásicos/farmacologia , Preparações de Ação Retardada/farmacologia , Íons , Lipossomos
19.
Curr Protein Pept Sci ; 19(9): 858-875, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28762306

RESUMO

Protein homeostasis (proteostasis) is achieved by the interplay among various components and pathways inside a cell. Dysfunction in proteostasis leads to protein misfolding and aggregation which is ubiquitously associated with many neurodegenerative disorders, although the exact role of these aggregate in the pathogenesis remains unknown. Many neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and others are characterized by the conversion of specific protein aggregates into protein inclusions and/or plaques in degenerating brains. Apart from the conventional disease specific proteins, such as amyloid-ß, α - synuclein, huntingtin protein, and prions that are known to aggregate, a number of other proteins play a vital role in aggravating the disease condition. In this review, we discuss the disease etiology, mechanism, the role of various pathways, molecular machinery including molecular chaperones, protein degradation pathways, and the active formation of inclusions in various neurodegenerative diseases. We also highlight the approaches, strategies, and methods that have been used for the treatment of these complex diseases over the years and the efforts that have potential in the near future.


Assuntos
Doenças Neurodegenerativas/terapia , Proteínas/metabolismo , Proteômica/métodos , Desenho de Fármacos , Humanos , Chaperonas Moleculares/metabolismo , Terapia de Alvo Molecular , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/metabolismo , Dobramento de Proteína , Multimerização Proteica , Proteínas/antagonistas & inibidores , Proteólise , Proteostase
20.
J Drug Target ; 26(2): 162-171, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28671003

RESUMO

Fibrin-based polymeric systems have now emerged as efficient carriers of drugs, growth factors, genes, and cells. Earlier, we have reported fibrin-based plasma beads (PB), prepared from clotted whole plasma, as an efficient system for the controlled release of entrapped therapeutics. In the present study, we investigate the dual entrapment in erythrocytes and PB, as potential particulate antigen delivery system in rabbit and mice, with yeast invertase as the model antigen. Preparations used for immunisation include- invertase entrapped in erythrocytes, the same further entrapped in PB, and crosslinked with glutaraldehyde. While route of administration of the antigen only moderately affected the antibody titres, strategies slowing its release from PB increased the antibody titres remarkably, especially after a booster. Entrapment of erythrocytes entrapped antigen in the PB and further crosslinking with glutaraldehyde also resulted in significant alterations of IgG1/IgG2a ratio, indicating a shift towards humoral response. The elicited immune response was more marked in rabbits as compared to that in mice. Considering the well-known toxicity of the adjuvant, comparable antibody titres induced by the erythrocyte-plasma bead system was encouraging in the induction of humoral immunity.


Assuntos
Micropartículas Derivadas de Células/imunologia , Eritrócitos , Plasma/química , Animais , Antígenos/química , Antígenos/imunologia , Antígenos de Fungos/imunologia , Micropartículas Derivadas de Células/química , Sistemas de Liberação de Medicamentos , Camundongos , Camundongos Endogâmicos BALB C , Microesferas , beta-Frutofuranosidase/imunologia
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