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1.
Development ; 151(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38345270

RESUMO

Mitochondrial morphology dynamics regulate signaling pathways during epithelial cell formation and differentiation. The mitochondrial fission protein Drp1 affects the appropriate activation of EGFR and Notch signaling-driven differentiation of posterior follicle cells in Drosophila oogenesis. The mechanisms by which Drp1 regulates epithelial polarity during differentiation are not known. In this study, we show that Drp1-depleted follicle cells are constricted in early stages and present in multiple layers at later stages with decreased levels of apical polarity protein aPKC. These defects are suppressed by additional depletion of mitochondrial fusion protein Opa1. Opa1 depletion leads to mitochondrial fragmentation and increased reactive oxygen species (ROS) in follicle cells. We find that increasing ROS by depleting the ROS scavengers, mitochondrial SOD2 and catalase also leads to mitochondrial fragmentation. Further, the loss of Opa1, SOD2 and catalase partially restores the defects in epithelial polarity and aPKC, along with EGFR and Notch signaling in Drp1-depleted follicle cells. Our results show a crucial interaction between mitochondrial morphology, ROS generation and epithelial cell polarity formation during the differentiation of follicle epithelial cells in Drosophila oogenesis.


Assuntos
Drosophila , Dinâmica Mitocondrial , Animais , Drosophila/genética , Drosophila/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Dinâmica Mitocondrial/genética , Catalase , Receptores ErbB/genética , Receptores ErbB/metabolismo , Dinaminas/genética , Dinaminas/metabolismo , Proteínas Mitocondriais/metabolismo
2.
PLoS Genet ; 18(2): e1010055, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35157701

RESUMO

Optimal mitochondrial function determined by mitochondrial dynamics, morphology and activity is coupled to stem cell differentiation and organism development. However, the mechanisms of interaction of signaling pathways with mitochondrial morphology and activity are not completely understood. We assessed the role of mitochondrial fusion and fission in the differentiation of neural stem cells called neuroblasts (NB) in the Drosophila brain. Depleting mitochondrial inner membrane fusion protein Opa1 and mitochondrial outer membrane fusion protein Marf in the Drosophila type II NB lineage led to mitochondrial fragmentation and loss of activity. Opa1 and Marf depletion did not affect the numbers of type II NBs but led to a decrease in differentiated progeny. Opa1 depletion decreased the mature intermediate precursor cells (INPs), ganglion mother cells (GMCs) and neurons by the decreased proliferation of the type II NBs and mature INPs. Marf depletion led to a decrease in neurons by a depletion of proliferation of GMCs. On the contrary, loss of mitochondrial fission protein Drp1 led to mitochondrial clustering but did not show defects in differentiation. Depletion of Drp1 along with Opa1 or Marf also led to mitochondrial clustering and suppressed the loss of mitochondrial activity and defects in proliferation and differentiation in the type II NB lineage. Opa1 depletion led to decreased Notch signaling in the type II NB lineage. Further, Notch signaling depletion via the canonical pathway showed mitochondrial fragmentation and loss of differentiation similar to Opa1 depletion. An increase in Notch signaling showed mitochondrial clustering similar to Drp1 mutants. Further, Drp1 mutant overexpression combined with Notch depletion showed mitochondrial fusion and drove differentiation in the lineage, suggesting that fused mitochondria can influence differentiation in the type II NB lineage. Our results implicate crosstalk between proliferation, Notch signaling, mitochondrial activity and fusion as an essential step in differentiation in the type II NB lineage.


Assuntos
Proteínas de Drosophila , Células-Tronco Neurais , Animais , Diferenciação Celular/genética , Proliferação de Células/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Dinâmica Mitocondrial/genética , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Células-Tronco Neurais/metabolismo
3.
Mol Biol Rep ; 50(1): 65-76, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36306008

RESUMO

BACKGROUND: In rice, drought stress at reproductive stage drastically reduces yield, which in turn hampers farmer's efforts towards crop production. The majority of the rice varieties have resistance genes against several abiotic and biotic stresses. Therefore, the traditional landraces were studied to identify QTLs/candidate genes associated with drought tolerance. METHODS AND RESULTS: A high-density SNP-based genetic map was constructed using a Genotyping-by-sequencing (GBS) approach. The recombinant inbred lines (RILs) derived from crossing 'Banglami × Ranjit' were used for QTL analysis. A total map length of 1306.424 cM was constructed, which had an average inter-marker distance of 0.281 cM. The phenotypic evaluation of F6 and F7 RILs were performed under drought stress and control conditions. A total of 42 QTLs were identified under drought stress and control conditions for yield component traits explaining 1.95-13.36% of the total phenotypic variance (PVE). Among these, 19 QTLs were identified under drought stress conditions, whereas 23 QTLs were located under control conditions. A total of 4 QTLs explained a PVE ≥ 10% which are considered as the major QTLs. Moreover, bioinformatics analysis revealed the presence of 6 candidate genes, which showed differential expression under drought and control conditions. CONCLUSION: These QTLs/genes may be deployed for marker-assisted pyramiding to improve drought tolerance in the existing rice varieties.


Assuntos
Oryza , Oryza/genética , Secas , Genótipo , Mapeamento Cromossômico/métodos , Locos de Características Quantitativas/genética , Fenótipo
4.
Mol Biol Rep ; 50(8): 6349-6359, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37314604

RESUMO

BACKGROUND: Drought stress is a major constraint for rice production worldwide. Reproductive stage drought stress (RSDS) leads to heavy yield losses in rice. The prospecting of new donor cultivars for identification and introgression of QTLs of major effect (Quantitative trait locus) for drought tolerance is crucial for the development of drought-resilient rice varieties. METHODS AND RESULTS: Our study aimed to map QTLs associated with yield and its related traits under RSDS conditions. A saturated linkage map was constructed using 3417 GBS (Genotyping by sequencing) derived SNP (Single nucleotide polymorphism) markers spanning 1924.136 cM map length with an average marker density of 0.56 cM, in the F3 mapping population raised via cross made between the traditional ahu rice cultivar, Koniahu (drought tolerant) and a high-yielding variety, Disang (drought susceptible). Using the Inclusive composite interval mapping approach, 35 genomic regions governing yield and related traits were identified in pooled data from 198 F3 and F4 segregating lines evaluated for two consecutive seasons under both RSDS and irrigated control conditions. Of the 35 QTLs, 23 QTLs were identified under RSDS with LOD (Logarithm of odds) values ranging between 2.50 and 7.83 and PVE (phenotypic variance explained) values of 2.95-12.42%. Two major QTLs were found to be linked to plant height (qPH1.29) and number of filled grains per panicle (qNOG5.12) under RSDS. Five putative QTLs for grain yield namely, qGY2.00, qGY5.05, qGY6.16, qGY9.19, and qGY10.20 were identified within drought conditions. Fourteen QTL regions having ≤ 10 Mb QTL interval size were further analysed for candidate gene identification and a total of 4146 genes were detected out of these 2263 (54.63%) genes were annotated to at least one gene ontology (GO) term. CONCLUSION: Several QTLs associated with grain yield and yield components and putative candidate genes were identified. The putative QTLs and candidate genes identified could be employed to augment drought resilience in rice after further validation through MAS strategies.


Assuntos
Oryza , Locos de Características Quantitativas , Locos de Características Quantitativas/genética , Oryza/genética , Secas , Fenótipo , Mapeamento Cromossômico/métodos , Grão Comestível/genética
5.
AAPS PharmSciTech ; 21(7): 260, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32944787

RESUMO

Niclosamide (NIC), an anthelminthic drug, is found to be promising in overcoming the problem of various types of drug-resistant cancer. In spite of strong anti-proliferative effect, NIC shows low aqueous solubility, leading to poor bioavailability. To overcome this limitation, and enhance its physicochemical properties and pharmacokinetic profile, we used co-crystallization technique as a promising strategy. In this work, we brought together the crystal and particle engineering at a time using spray drying to enhance physicochemical and aerodynamic properties of co-crystal particle for inhalation purpose. We investigated the formation and evaluation of pharmaceutical co-crystals of niclosamide-nicotinamide (NIC-NCT) prepared by rapid, continuous and scalable spray drying method and compared with conventional solvent evaporation technique. The newly formed co-crystal was evaluated by XRPD, FTIR, Raman spectroscopy and DSC, which showed an indication of formation of H bonds between drug (NIC) and co-former (NCT) as a major binding force in co-crystal development. The particle geometry of co-crystals including spherical shape, size 1-5 µm and aerodynamic properties (ED, 97.1 ± 8.9%; MMAD, 3.61 ± 0.87 µm; FPF, 71.74 ± 6.9% and GSD 1.46) attributes suitable for inhalation. For spray-dried co-crystal systems, an improvement in solubility characteristics (≥ 14.8-fold) was observed, relative to pure drug. To investigate the anti-proliferative activity, NIC-NCT co-crystals were investigated on A549 human lung adenomas cells, which showed a superior cytotoxic activity compared with pure drug. Mechanistically, NIC-NCT co-crystals enhanced autophagic flux in cancer cell which demonstrates autophagy-mediated cell death as shown by confocal microscopy. This technique could help in improving bioavailability of drug, hence reducing the need for high dosages and signifying a novel paradigm for future clinical applications.


Assuntos
Autofagia/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Niacinamida/farmacologia , Niclosamida/farmacologia , Administração por Inalação , Varredura Diferencial de Calorimetria , Cristalização , Dessecação , Composição de Medicamentos , Niacinamida/administração & dosagem , Niclosamida/administração & dosagem , Tamanho da Partícula , Solubilidade , Análise Espectral Raman
6.
AAPS PharmSciTech ; 20(6): 241, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31250260

RESUMO

Particulate drug delivery systems (PDDS) have been broadly explored as platforms for delivery of drugs, enzymes, cells, and vaccines for pharmaceutical applications. Studies suggest that microspheres (MS) can stimulate innate immune cells even without a drug payload; however, less is known regarding how they impact host cells in dealing with the bacillary infection. We examined the role of drug-free inhalable alginate microspheres (A-MS) on phagocytosis efficiency and subsequent immune cell activation in Escherichia coli-infected THP-1-derived macrophages. Alginate particles have been widely investigated as carriers for prolonged delivery of bioactive (i.e., drugs, diagnostics, and vaccines). A-MS were fabricated by industry scalable spray-congealing process using divalent cation-induced gelification. E. coli-infected macrophages (multiplicity of infection (MOI 1:10) were treated with drug-free A-MS, where we found a consistent moderate reduction in bacillary viability. Particles were more efficiently and rapidly phagocytized by infected macrophages as compared with normal macrophage cells. Subsequently, A-MS induced markers of M1 macrophage responses and stimulated the processing and secretion of pro-inflammatory cytokines (IL-6, IL-12). It also notably augmented the generation of reactive oxygen species (ROS) and nitric oxide (NO) in infected cells. Results illustrate that, the blank A-MS (without a drug payload) able to moderately check the growth of intracellular E. coli (without significant cytotoxicity) by modulating the M1 inflammatory response by host cells. This "added value" can be utilized in the design and development of therapeutic system with the additional advantage of immune-modulatory activity, in addition to serving as a drug carrier.


Assuntos
Alginatos/farmacologia , Escherichia coli/imunologia , Imunidade Inata/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Microesferas , Alginatos/química , Animais , Citocinas/metabolismo , Humanos , Macrófagos/imunologia , Óxido Nítrico/metabolismo , Fagocitose/efeitos dos fármacos
7.
Biomater Adv ; 160: 213853, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636119

RESUMO

Patients with rheumatoid arthritis (RA) often have one or more painfuljoints despite adequate medicine. Local drug delivery to the synovial cavity bids for high drug concentration with minimal systemic adverse effects. However, anti-RA drugs show short half-lives in inflamed joints after intra-articular delivery. To improve the therapeutic efficacy, it is essential to ensure that a drug is only released from the formulation when it is needed. In this work, we developed an intelligent "Self-actuating" drug delivery system where Disease-modifying anti-rheumatic Drug (DMARD) methotrexate is incorporated within a matrix intended to be injected directly into joints. This formulation has the property to sense the need and release medication only when joints are inflamed in response to inflammatory enzyme Matrix metalloproteinases (MMP). These enzymes are important proteases in RA pathology, and several MMP are present in augmented levels in synovial fluid and tissues. A high level of MMP present in synovial tissues of RA patients would facilitate the release of drugs in response and ascertain controlled drug release. The formulation is designed to be stable within the joint environment, but to dis-assemble in response to inflammation. The synthesized enzyme-responsive methotrexate (Mtx) encapsulated micron-sized polymer-lipid hybrid hydrogel microspheres (Mtx-PLHM) was physiochemically characterized and tested in synovial fluid, Human Fibroblast like synoviocytes (h-FLS) (derived from RA patients) and a rat arthritic animal model. Mtx-PLHM can self-actuate and augment the release of Mtx drug upon contact with either exogenously added MMP or endogenous MMP present in the synovial fluid of patients with RA. The drug release from the prepared formulation is significantly amplified to several folds in the presence of MMP-2 and MMP-9 enzymes. In the rat arthritic model, Mtx-PLHM showed promising therapeutic results with the significant alleviation of RA symptoms through decrease in joint inflammation, swelling, bone erosion, and joint damage examined by X-ray analysis, histopathology and immune-histology. This drug delivery system would be nontoxic as it releases more drug only during the period of exacerbation of inflammation. This will simultaneously protect patients from unwanted side effects when the disease is inactive and lower the need for repeated joint injections.


Assuntos
Antirreumáticos , Artrite Reumatoide , Preparações de Ação Retardada , Hidrogéis , Metotrexato , Microesferas , Sinoviócitos , Animais , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Humanos , Metotrexato/farmacologia , Metotrexato/uso terapêutico , Metotrexato/química , Metotrexato/administração & dosagem , Hidrogéis/química , Sinoviócitos/efeitos dos fármacos , Sinoviócitos/metabolismo , Sinoviócitos/patologia , Ratos , Antirreumáticos/farmacologia , Antirreumáticos/administração & dosagem , Antirreumáticos/uso terapêutico , Antirreumáticos/farmacocinética , Liberação Controlada de Fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Masculino , Inflamação/tratamento farmacológico , Inflamação/patologia , Metaloproteinases da Matriz/metabolismo , Líquido Sinovial/efeitos dos fármacos , Líquido Sinovial/metabolismo
8.
Mol Neurobiol ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809370

RESUMO

Changes in the transition metal homeostasis in the brain are closely linked with Alzheimer's disease (AD), including intraneuronal iron accumulation and extracellular copper and zinc pooling in the amyloid plague. The brain copper, zinc, and iron surplus are commonly acknowledged characteristics of AD, despite disagreements among some. This has led to the theory that oxidative stress resulting from abnormal homeostasis of these transition metals may be a causative explanation behind AD. In the nervous system, the interaction of metals with proteins appears to be an essential variable in the development or suppression of neurodegeneration. Chelation treatment may be an option for treating neurodegeneration induced by transition metal ion dyshomeostasis. Some clinicians even recommend using chelating agents as an adjunct therapy for AD. The current review also looks at the therapeutic strategies that have been attempted, primarily with metal-chelating drugs. Metal buildup in the nervous system, as reported in the AD, could be the result of compensatory mechanisms designed to improve metal availability for physiological functions.

9.
Antimicrob Agents Chemother ; 57(2): 1050-2, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23183441

RESUMO

Inhalable clofazimine-containing dry powder microparticles (CFM-DPI) and native clofazimine (CFM) were evaluated for activity against Mycobacterium tuberculosis in human monocyte-derived macrophage cultures and in mice infected with a low-dose aerosol. Both formulations resulted in 99% killing at 2.5 µg/ml in vitro. In mice, 480 µg and 720 µg CFM-DPI inhaled twice per week over 4 weeks reduced numbers of CFU in the lung by as much as log(10) 2.6; 500 µg oral CFM achieved a log(10) 0.7 reduction.


Assuntos
Antituberculosos/uso terapêutico , Clofazimina/uso terapêutico , Mycobacterium tuberculosis/efeitos dos fármacos , Nanopartículas/uso terapêutico , Tuberculose/tratamento farmacológico , Administração por Inalação , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Células Cultivadas , Sistemas de Liberação de Medicamentos , Pulmão/microbiologia , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Camundongos , Testes de Sensibilidade Microbiana , Resultado do Tratamento
10.
Curr Pharm Des ; 29(13): 984-1001, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37038685

RESUMO

Rheumatoid arthritis (RA) is the most common form of the chronic inflammatory autoimmune disease characterized by chronic synovitis, synovial proliferation, and cellular infiltration. Further, it leads to bone erosion, destruction of articular cartilage, intense joint pain, swelling, and a high rate of disability, causing an immense load on human health. If the disease is identified early on, and the patient has continuous and timely treatment, many patients can achieve remission. Although research in RA has made considerable progress, conventional therapies are still the most popular treatment options for most people with RA. But, conventional therapies are hampered by various drawbacks, including higher doses, low solubility and permeability, poor bioavailability, a high level of first-pass metabolism, adaptive treatment tolerance (ATT), and long-term drug use. These drawbacks can result in severe side effects and drug toxicity in patients. Advances in polymer science and the application of nanotechnology in drug delivery systems have provided new possibilities in the treatment of RA by developing new-generation smart drug delivery systems (SDDSs). The shortcomings of non-specific drug distribution and uncontrollable drug release by traditional delivery systems have motivated the creation of next-generation SDDSs. These new smart drug delivery treatment methods have significantly changed the course of RA. Such systems can improve drug delivery by virtue of their multi-functionality and targeting capabilities. The ultimate objective of next-generation SDDSs is to deliver medication at the optimal time with precise dosage and efficiency and specificity to the targeted site (such as cells, tissues, and organs), which can aid patients to adhere better to their therapy. This review highlights and discusses the various next-generation SDDSs along with the conventional treatment options available for RA management.


Assuntos
Artrite Reumatoide , Humanos , Sistemas de Liberação de Medicamentos , Nanotecnologia , Liberação Controlada de Fármacos , Solubilidade
11.
Biomater Adv ; 154: 213594, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37657277

RESUMO

The rise of tuberculosis (TB) superbugs has impeded efforts to control this infectious ailment, and new treatment options are few. Paradoxical Inflammation (PI) is another major problem associated with current anti-TB therapy, which can complicate the treatment and leads to clinical worsening of disease despite a decrease in bacterial burden in the lungs. TB infection is generally accompanied by an intense local inflammatory response which may be critical to TB pathogenesis. Clofazimine (CLF), a second-line anti-TB drug, delineated potential anti-mycobacterial effects in-vitro and in-vivo and also demonstrated anti-inflammatory potential in in-vitro experiments. However, clinical implications may be restricted owing to poor solubility and low bioavailability rendering a suboptimal drug concentration in the target organ. To unravel these issues, nanocrystals of CLF (CLF-NC) were prepared using a microfluidizer® technology, which was further processed into micro-sized CLF nano-clusters (CLF-NCLs) by spray drying technique. This particle engineering offers combined advantages of micron- and nano-scale particles where micron-size (∼5 µm) promise optimum aerodynamic parameters for the finest lung deposition, and nano-scale dimensions (∼600 nm) improve the dissolution profile of apparently insoluble clofazimine. An inhalable formulation was evaluated against virulent mycobacterium tuberculosis in in-vitro studies and in mice infected with aerosol TB infection. CLF-NCLs resulted in the significant killing of virulent TB bacteria with a MIC value of ∼0.62 µg/mL, as demonstrated by Resazurin microtiter assay (REMA). In TB-infected mice, inhaled doses of CLF-NCLs equivalent to ∼300 µg and âˆ¼ 600 µg of CLF administered on every alternate day over 30 days significantly reduced the number of bacteria in the lung. With an inhaled dose of ∼600 µg/mice, reduction of mycobacterial colony forming units (CFU) was achieved by ∼1.95 Log10CFU times compared to CLF administered via oral gavage (∼1.18 Log10CFU). Lung histology scoring showed improved pathogenesis and inflammation in infected animals after 30 days of inhalation dosing of CLF-NCLs. The levels of pro-inflammatory mediators, including cytokines, TNF-α & IL-6, and MMP-2 in bronchoalveolar lavage fluid (BAL-F) and lung tissue homogenates, were attenuated after inhalation treatment. These pre-clinical data suggest inhalable CLF-NCLs are well tolerated, show significant anti-TB activity and apparently able to tackle the challenge of paradoxical chronic lung inflammation in murine TB model.


Assuntos
Pneumonia , Tuberculose , Camundongos , Animais , Clofazimina/farmacologia , Clofazimina/uso terapêutico , Aerossóis e Gotículas Respiratórios , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Pneumonia/tratamento farmacológico , Inflamação/tratamento farmacológico
12.
Int J Pharm ; 634: 122585, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36621703

RESUMO

Obesity is a metabolic disease, which is one of the major causes of morbidity and mortality, where therapeutic options are limited. Treatment of obesity is necessary as it is associated with fatal complications like diabetes mellitus, cardiovascular disease, non-alcoholic fatty liver disease, osteoarthritis, and many more. Liraglutide (Lir), a synthetic analogue of Glucagon-like Peptide-1 (GLP-1), is the FDA approved anti-obesity drug, however, its major limitation is its clinical application which needs frequent parenteral injections. To address the issue of regular injection, we have synthesized a fat fighting oral nano-formulation of liraglutide with a sustained release feature, which was evaluated against high fat diet (HFD) induced obesity in mice. Experimental obesity was induced in mice by feeding HFD for 26 weeks. Lir nanoparticles (NP) were fabricated with chitosan via ion-gelation technique and were coated with Eudragit@S100 to protect the drug in harsh gastric conditions. Physiochemical characterization of Eu-Lir-Cs-NP demonstrated a small particle size of 253.1 ± 1.21 nm with âˆ¼ 9.74 % loading and âˆ¼ 72.11 % encapsulation efficiency of the drug. In-vitro studies showed successful cellular uptake of NP in Caco-2 cells and were stable in various enteric fluid pH conditions. Eudragit@S100 coated chitosan NP were able to protect the drug from harsh gastric pH conditions with more than âˆ¼ 74% of recovery. Treatment of two weeks of liraglutide Eu-Lir-Cs-NP (0.1, 0.2 and 0.4 mg/kg, orally; twice daily) moderately reduces obesity in mice as evidenced by a reduction in the body weight, blood glucose, serum total cholesterol, serum triglyceride, serum resistin and serum insulin level of mice. In addition, significant reduction of liver weight, abdominal white adipose tissue, and hepatic oxidative stress were noted. Our results suggest that chitosan-based NP of liraglutide can be an effective and convenient formulation for the management of obesity.


Assuntos
Quitosana , Liraglutida , Humanos , Camundongos , Animais , Liraglutida/farmacologia , Liraglutida/uso terapêutico , Células CACO-2 , Ácidos Polimetacrílicos , Hipoglicemiantes
13.
Curr Protein Pept Sci ; 23(10): 643-656, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35619262

RESUMO

Tuberculosis (TB) is a highly contagious infection with extensive mortality and morbidity. The rise of TB-superbugs (drug-resistant strains) with the increase of their resistance to conventional antibiotics has prompted a further search for new anti-mycobacterial agents. It is difficult to breach the barriers around TB bacteria, including mycolic cell wall, granuloma, biofilm and mucus, by conventional antibiotics in a short span of time. Hence, there is an essential need for molecules with an unconventional mode of action and structure that can efficiently break the barriers around mycobacterium. Antimicrobial peptides (AMP) are essential components of innate immunity having cationic and amphipathic characteristics. Lines of evidence show that AMPs have good myco-bactericidal and antibiofilm activity against normal as well as antibiotic-resistant TB bacteria. These peptides have shown direct killing of bacteria by membrane lysis and indirect killing by activation of innate immune response in host cells by interacting with the component of the bacterial membrane and intracellular targets through diverse mechanisms. Despite a good anti-mycobacterial activity, some undesirable characteristics are also associated with AMP, including hemolysis, cytotoxicity, susceptibility to proteolysis and poor pharmacokinetic profile, and hence only a few clinical studies have been conducted with these biomolecules. The design of new combinatorial therapies, including AMPs and particulate drug delivery systems, could be new potential alternatives to conventional antibiotics to fight MDR- and XDRTB. This review outlined the array of AMP roles in TB therapy, possible mechanisms of actions, activities, and current advances in pragmatic strategies to improve challenges accompanying the delivery of AMP for tuberculosis therapeutics.


Assuntos
Peptídeos Antimicrobianos , Tuberculose , Humanos , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/química , Bactérias , Tuberculose/tratamento farmacológico
14.
Curr Drug Metab ; 23(7): 571-583, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35950248

RESUMO

BACKGROUND: Diabetic peripheral neuropathy is the most common complication of diabetes mellitus. Epalrestat, an aldose reductase inhibitor, has been approved for clinical therapy for diabetic peripheral neuropathic pain. In the present study, solid lipid-based nanoparticles are used for oral administration of epalrestat (E-SLN) and evaluated against diabetic neuropathic pain in a rat model. METHODS: Experimental diabetes in rats was induced by a single dose of streptozotocin (STZ) administration. The therapeutic efficiency of Epalrestat nanoparticles (0.25, 0.50, 1, and 5 mg/kg) in diabetic rats was studied. STZinduced diabetic rats were treated with different doses of E-SLN for 8 weeks. The nanoparticles were orally administered at a single dose in rats, and the various parameters related to peripheral neuropathy were evaluated and compared with the bare drug. The blood glucose level was estimated by standard glucometer, HbA1c, triglycerides, total cholesterol, and liver function test (ALT and AST) were analyzed by blood samples collected from retro-orbital plexus. Oxidative stress markers and Na+K+ATPase, TNF-α, and IL-1ß levels were measured in the homogenate of sciatic nerves. Behavioral tests were also performed by the hot plate method and tail-flick method. RESULTS: E-SLN synthesized by the micro-emulsification method was 281 ± 60 nm in size, and encapsulation efficacy was found to be 88 ± 2%. Optimized E-SLN were characterized and found to be optimum in size, spherical shape, decent encapsulation efficiency, stable at acidic gastric pH, and suitable for oral delivery. E-SLNs did not significantly reverse the STZ-induced elevated blood glucose level (FBS and PPBS), HbA1c, triglycerides, and total cholesterol but significantly improved TNF-α, IL-1ß, and increased Na+K+ATPase levels, oxidative stress marker and ALT, AST in the treated rat group as compared with the diabetic group. Doses of E-SLN, i.e. 0.5, 1.0, 2.5, and 5 mg/kg, significantly increased the tail-flick latency time and hot plate response time in a dose-dependent manner compared with the diabetic group. CONCLUSION: Thus, it is suggested that E-SLN were equally effective and less hepatotoxic compared with the standard treatment of epalrestat. To the best of our knowledge, we, for the first time, propose the orally deliverable E-SLN that ameliorates STZ-induced diabetes neuropathic pain effectively as compared with conventional epalrestat.


Assuntos
Diabetes Mellitus Experimental , Neuropatias Diabéticas , Neuralgia , Ratos , Animais , Neuropatias Diabéticas/tratamento farmacológico , Diabetes Mellitus Experimental/tratamento farmacológico , Estreptozocina/uso terapêutico , Aldeído Redutase , Glicemia , Hemoglobinas Glicadas/uso terapêutico , Fator de Necrose Tumoral alfa/uso terapêutico , Neuralgia/tratamento farmacológico , Triglicerídeos/uso terapêutico , Colesterol , Adenosina Trifosfatases/uso terapêutico , Lipídeos
15.
ACS Appl Bio Mater ; 4(6): 5324-5335, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35007013

RESUMO

We report the formulation of aminocellulose-grafted polymeric nanoparticles containing LCS-1 for synthetic lethal targeting of checkpoint kinase 2 (CHEK2)-deficient HCT116 colon cancer (CRC) cells to surpass the limitations associated with the solubility of LCS-1 (a superoxide dismutase inhibitor). Aminocellulose (AC), a highly biocompatible and biodegradable hydrophilic polymer, was grafted over polycaprolactone (PCL), and a nanoprecipitation method was employed for formulating nanoparticles containing LCS-1. In this study, we exploited the synthetic lethal interaction between SOD1 and CHEK2 for the specific inhibition of CHEK2-deficient HCT116 CRC cells using LCS-1-loaded PCL-AC NPs. Furthermore, the effects of formation of protein corona on PCL-AC nanoparticles were also assessed in terms of size, cellular uptake, and cell viability. LCS-1-loaded NPs were evaluated for their size, zeta potential, and polydispersity index using a zetasizer, and their morphological characteristics were assessed by transmission electron microscopy, scanning electron microscopy, and atomic force microscopy analyses. Cellular internalization using confocal microscopy exhibited that nanoparticles were uptaken by HCT116 cells. Also, nanoparticles were cytocompatible as they did not induce cytotoxicity in hTERT and HEK-293 cells. The LCS-1-loaded PCL-AC NPs were quite hemocompatible and were 240 times more selective in killing CHEK2-deficient cells as compared to CHEK2-proficient CRC cells. Moreover, PCL-AC NPs exhibited that the protein corona-coated nanoparticles were incubated in the human and fetal bovine sera as visualized by SDS-PAGE. A slight increment in hydrodynamic diameter was observed for corona-coated PCL-AC nanoparticles, and size increment was further confirmed by TEM. Corona-coated PCL-AC NPs also exhibited cellular uptake as demonstrated by flow cytometric analysis and did not cause cytotoxic effects on hTERT cells. The nanoformulation was developed to enhance therapeutic potential of the drug LCS-1 for enhanced lethality of colorectal cancer cells with CHEK2 deficiency.


Assuntos
Neoplasias do Colo , Nanopartículas , Coroa de Proteína , Animais , Bovinos , Quinase do Ponto de Checagem 2 , Células HEK293 , Humanos , Polímeros
16.
Mitochondrion ; 58: 111-122, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33618020

RESUMO

Investigation of human mitochondrial (mt) genome variation has been shown to provide insights to the human history and natural selection. By analyzing 24,167 human mt-genome samples, collected for five continents, we have developed a co-mutation network model to investigate characteristic human evolutionary patterns. The analysis highlighted richer co-mutating regions of the mt-genome, suggesting the presence of epistasis. Specifically, a large portion of COX genes was found to co-mutate in Asian and American populations, whereas, in African, European, and Oceanic populations, there was greater co-mutation bias in hypervariable regions. Interestingly, this study demonstrated hierarchical modularity as a crucial agent for these co-mutation networks. More profoundly, our ancestry-based co-mutation module analyses showed that mutations cluster preferentially in known mitochondrial haplogroups. Contemporary human mt-genome nucleotides most closely resembled the ancestral state, and very few of them were found to be ancestral-variants. Overall, these results demonstrated that subpopulation-based biases may favor mitochondrial gene specific epistasis.


Assuntos
Epistasia Genética , Evolução Molecular , Genes Mitocondriais , Grupos Populacionais/genética , Humanos , Mutação
17.
Mater Sci Eng C Mater Biol Appl ; 119: 111582, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321628

RESUMO

Ulcerative colitis (UC) is an inflammatory condition involving ulcers in colon and rectum. Conventional treatments for colitis confront serious limitations like off target systemic side effects, drug degradation and inactivation, restricted absorption and other complications culminating in poor bioavailability. These limitations necessitate localized drug delivery to inflamed colon such that drug can bypass abrasive gastric surroundings, availing protection form gastric acid and has selective access to colonic mucosa. Therefore, present study was designed to formulate Eudragit-S100 coated 5-amino salicylic acid (5-ASA)-loaded gelatin nanoparticles (NPs) for localized delivery of 5-ASA for treatment of ulcerative colitis. NPs were formulated by nanoprecipitation and solvent evaporation method, had hydrodynamic diameter of 225-250 nm, smooth and spherical surface morphology under TEM, SEM and AFM. Oral administration of NPs ameliorated disease activity indices like fecal occult bleeding, colon length and stool consistency. NPs treatment significantly reduced mast cells infiltration in colon, restored protective mucin layer and appreciably reinstated colonic histoarchitecture. Furthermore, inflammatory biomarkers like TNF-α, IL1-ß, COX-2, iNOS, myeloperoxidase and nitrite levels were also significantly reduced by NPs treatment. Overall, results of this study indicate that 5-ASA NPs possessed superior therapeutic efficacy over free 5-ASA in experimental colitis and these results are attributed to their ability to significantly suppress inflammation.


Assuntos
Colite Ulcerativa , Mesalamina , Nanopartículas , Administração Oral , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colo , Sistemas de Liberação de Medicamentos , Gelatina/uso terapêutico , Mesalamina/farmacologia , Mesalamina/uso terapêutico
18.
Mater Sci Eng C Mater Biol Appl ; 121: 111851, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33579485

RESUMO

Ulcerative colitis (UC) is an idiopathic bowel disease involving chronic inflammation and ulcers in colon and implicates severe epithelial damage with disruption in colon homeostasis. Presently existing treatments possess serious concerns like off target effects and adverse reactions, drug inactivation, poor absorption and other complications resulting in poor bioavailability. In context of high risk of thrombotic events in UC patients, heparin can offer appreciable benefits in UC management due to its remarkable anti-coagulating properties, its ability to intervene inflammatory pathways and acceleration of wound healing process. However, oral administration of heparin being impractical due to harsh gastric acidic environment and heparin degradation, conventional heparin administration is done via intravenous route. Present study was designed to formulate, characterize and evaluate sustained release heparin formulation in mice model of experimental colitis. Heparin liposomes (HLp) were formulated by solvent evaporation and extrusion process and possessed hydrodynamic diameter of 242 ± 4.3 nm. Size, shape and surface morphology was confirmed by TEM, SEM and AFM micrographs while encapsulation efficiency and loading of heparin in optimized HLp were 59.61% and 12.27%, respectively. HLp enema administration ameliorated gross disease indices like body weight, colon length, stool consistency, fecal occult blood. Further, anti-inflammatory efficacy of HLp was established in histopathological analysis where HLp appreciably restored protective mucin layer, colon epithelial mucosal histoarchitecture and considerably attenuated mast cell infiltration in colon epithelia. Overall, results of this study indicate that HLp demonstrated an appreciable therapeutic efficacy in experimental colitis and these results are attributed to their ability to suppress inflammation.


Assuntos
Colite Ulcerativa , Animais , Colite Ulcerativa/tratamento farmacológico , Colo , Enema , Heparina de Baixo Peso Molecular/farmacologia , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Lipossomos , Camundongos
19.
Mater Sci Eng C Mater Biol Appl ; 123: 112027, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33812642

RESUMO

The tumor targeting and stimuli responsiveness behavior of intelligent drug delivery systems imparts effective therapeutic delivery and decreases the toxicity of conventional chemotherapeutic agents in off-target organs. To achieve the receptor targeting and smart drug release, several strategies have been employed to engineer nano-carrier with stimulus sensitivity. In this work, mannose receptor-targeted and matrix metalloproteinase (MMP) responsive gelatin nanoparticles were developed and assessed for its receptor targeting and "on-demand" controlled drug delivery in lung cancer therapeutics. MMPs are protease enzymes and over-expressed in tumorous tissues in all the stages of cancer. The cancer cells also have over-expressed mannose receptors on the cell surface. The surface decoration of gelatin nanoparticles with concanavalin A (con-A) tends to bind with mannose moiety of cell surface glycoproteins which enhances the cancer cell-specific higher uptake of nanoparticles. Gelatin nanoparticles have attracted significant attraction in recent years as a potential drug carrier because of its good biocompatibility and versatile physicochemical properties desirable to deliver the drug. Cisplatin was complexed with the gelatin matrix (CG-NP) to evaluate stimuli responsiveness with the lung cancer cells and its release pattern. In this smart inhalable delivery system, cisplatin loaded gelatin nanoparticles were surface decorated with con-A (CCG-NP). In tumorous cells, con-A coating is expected to enhance mannose receptor-specific cellular internalization of CCG-NP, and subsequently high level of MMP in tumor tissues would help to release cisplatin in response and ensures controlled drug release. The synthesized CCG-NP has shown enzyme triggered drug release and favorable endocytosis after incubation of 12 h compare to uncoated nanoparticles. The efficacy of CCG-NP significantly increased in presence of MMP-2 enzyme in lung cancer cell line A549 cells. It also significantly enhanced reactive oxygen species generation, cell cycle arrest in S and G2/M phase, and apoptosis in cancer cells. Therefore, inhalable CCG-NP promises a pragmatic approach to construct a receptor targeting and an "on-demand" drug delivery system to efficiently deliver the drug at the tumor site only.


Assuntos
Nanopartículas , Neoplasias , Linhagem Celular Tumoral , Concanavalina A , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Gelatina , Neoplasias/tratamento farmacológico
20.
Int J Pharm ; 608: 121097, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34534632

RESUMO

Tuberculosis (TB) treatment has become a challenge because of the natural presence of multilayered cell wall rich in lipids which restrict antibiotic permeability within the bacteria. The development of mutations conferring resistance has aggravated the situation. Consequently, maximum pharmaceutical efforts are required to improve the treatment, and antimicrobial peptides (AMPs) with antimycobacterial activity can be exploited as a new treatment strategy against TB. The synergistic interaction between conventional antibiotics and AMPs has broadened its application landscape. To overcome peptide instability and bioavailability issues, encapsulation of these bioactive in biocompatible polymers was adopted. In this study, the effect of synthetic AMPs HHC-8 [KIWWWWRKR] and MM-10 [MLLKKLLKKM] encapsulated in poly (ε-caprolactone) nanoparticles (PCL-NPs) was evaluated against mycobacteria using REMA (Resazurin Microtiter Assay Plate) technique. PCL encapsulation allowed us to load the required amount of peptides, i.e. HHC-8 and MM-10, with an efficiency of âˆ¼ 18.9 ± 5.24 and âˆ¼ 21.1 ± 6.19 % respectively, and sphere size was around 376.5 ± 14.9 nm and 289.87 ± 17.98 nm for PCL-HHC-8-NPs and PCL-MM-10-NPs, respectively. Minimal degradation and sustained release of peptides from nanoparticles improved antimicrobial activity, decreasing the MIC50 from 75 µg/ml to 18.75 µg/ml against M. smegmatis and from 75 µg/ml to 9 µg/ml against M. tuberculosis, respectively. The combinatorial MIC assays of encapsulated AMP with rifampicin antibiotics against M. smegmatis showed synergism between AMP-PCL-NPs and antibiotics with fractional inhibitory concentrations (FICs) around âˆ¼ 0.09. The combinations of AMP NPs also demonstrated synergy against the mycobacteria. Our findings suggest that enhanced efficacy is due to protection offered by AMPs encapsulation resulting in augmentation of membrane permeation by AMPs and enhanced accumulation of antibiotics within mycobacteria resulting in synergy. The study findings might assist in the preclinical development of AMP for the fight against TB.


Assuntos
Mycobacterium tuberculosis , Nanopartículas , Antibacterianos/farmacologia , Caproatos , Lactonas , Proteínas Citotóxicas Formadoras de Poros , Rifampina/farmacologia
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