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BACKGROUND: Hepatic lipoprotein receptor-related protein 1 (LRP-1) plays a central role in peripheral amyloid beta (Aß) clearance, but its importance in Alzheimer's disease (AD) pathology is understudied. Our previous work showed that intragastric alcohol feeding to C57BL/6 J mice reduced hepatic LRP-1 expression which correlated with significant AD-relevant brain changes. Herein, we examined the role of hepatic LRP-1 in AD pathogenesis in APP/PS1 AD mice using two approaches to modulate hepatic LRP-1, intragastric alcohol feeding to model chronic heavy drinking shown by us to reduce hepatic LRP-1, and hepato-specific LRP-1 silencing. METHODS: Eight-month-old male APP/PS1 mice were fed ethanol or control diet intragastrically for 5 weeks (n = 7-11/group). Brain and liver Aß were assessed using immunoassays. Three important mechanisms of brain amyloidosis were investigated: hepatic LRP-1 (major peripheral Aß regulator), blood-brain barrier (BBB) function (vascular Aß regulator), and microglia (major brain Aß regulator) using immunoassays. Spatial LRP-1 gene expression in the periportal versus pericentral hepatic regions was confirmed using NanoString GeoMx Digital Spatial Profiler. Further, hepatic LRP-1 was silenced by injecting LRP-1 microRNA delivered by the adeno-associated virus 8 (AAV8) and the hepato-specific thyroxine-binding globulin (TBG) promoter to 4-month-old male APP/PS1 mice (n = 6). Control male APP/PS1 mice received control AAV8 (n = 6). Spatial memory and locomotion were assessed 12 weeks after LRP-1 silencing using Y-maze and open-field test, respectively, and brain and liver Aß were measured. RESULTS: Alcohol feeding reduced plaque-associated microglia in APP/PS1 mice brains and increased aggregated Aß (p < 0.05) by ELISA and 6E10-positive Aß load by immunostaining (p < 0.05). Increased brain Aß corresponded with a significant downregulation of hepatic LRP-1 (p < 0.01) at the protein and transcript level, primarily in pericentral hepatocytes (zone 3) where alcohol-induced injury occurs. Hepato-specific LRP-1 silencing significantly increased brain Aß and locomotion hyperactivity (p < 0.05) in APP/PS1 mice. CONCLUSION: Chronic heavy alcohol intake reduced hepatic LRP-1 expression and increased brain Aß. The hepato-specific LRP-1 silencing similarly increased brain Aß which was associated with behavioral deficits in APP/PS1 mice. Collectively, our results suggest that hepatic LRP-1 is a key regulator of brain amyloidosis in alcohol-dependent AD.
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Doença de Alzheimer , Fígado , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Animais , Doença de Alzheimer/metabolismo , Masculino , Camundongos , Fígado/metabolismo , Amiloidose/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Etanol/administração & dosagem , Modelos Animais de Doenças , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismoRESUMO
Diabetes mellitus is a chronic and most prevalent metabolic disorder affecting 422â million the people worldwide and causing life-threatening associated conditions including disorders of kidney, heart, and nervous system as well as leg amputation and retinopathy. Steadily rising cases from the last few decades suggest the failure of currently available drugs in containment of this disease. α-Glucosidase is a potential target for effectively tackling this disease and attracting significant interest from medicinal chemists around the globe. Besides having a set of side effects, currently available α-glucosidase inhibitors (carbohydrate mimics) offer better tolerability, safety, and synergistic pharmacological outcomes with other antidiabetic drugs therefore medicinal chemists have working extensively over last three decades for developing alternative α-glucosidase inhibitors. The 1,2,3-Triazole nucleus is energetically used by various research groups around the globe for the development of α-glucosidase inhibitors posing it as an optimum scaffold in the field of antidiabetic drug development. This review is a systematic analysis of α-glucosidase inhibitors developed by employing 1,2,3-triazole scaffold with special focus on design strategies, structure-activity relationships, and mechanism of inhibitory effect. This article will act as lantern for medicinal chemists in developing of potent, safer, and effective α-glucosidase inhibitors with desired properties and improved therapeutic efficacy.
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Desenho de Fármacos , Inibidores de Glicosídeo Hidrolases , Triazóis , alfa-Glucosidases , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/síntese química , Relação Estrutura-Atividade , alfa-Glucosidases/metabolismo , alfa-Glucosidases/química , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/síntese química , Estrutura MolecularRESUMO
Selective delivery of chemotherapy to the tumor site while sparing healthy cells and tissues is an attractive approach for cancer treatment. Carriers such as peptides can facilitate selective tumor targeting and payload delivery. Peptides with specific affinity for the overexpressed cell-surface receptors in cancer cells are conjugated to chemotherapy to afford peptide-drug conjugates (PDCs) that show selective uptake by cancer cells. Using a 10-mer linear peptide (WxEAAYQrFL) called 18-4 that targets and binds breast cancer cells, we designed a peptide 18-4-doxorubicin (Dox) conjugate with high specific toxicity toward triple-negative breast cancer (TNBC) MDA-MB-231 cells and 30-fold lower toxicity to normal breast MCF10A epithelial cells. Here, we elucidate the in vivo activity of this potent and tumor-selective peptide 18-4-Dox conjugate in mice bearing orthotopic MDA-MB-231 tumors. Mice treated with four weekly injections of the conjugate showed significantly lower tumor volumes compared to mice treated with free Dox at an equivalent Dox dose. Immunohistochemical (IHC) analysis of mice tissues revealed that treatment with a low dose of PDC (2.5 mg/kg of Dox equiv) reduced the expression of proliferation markers (PCNA and Ki-67) and increased apoptosis (evidenced by increased caspase-3 expression). At the same dose of free Dox (2.5 mg/kg), the expression of these markers was similar to that of saline treatment. Accordingly, significantly more Dox accumulated in tumors of conjugate-treated mice (7-fold) compared to the Dox-treated mice, while lower levels of Dox were observed in the liver, heart, and lungs of peptide-Dox conjugate-treated mice (up to 3-fold less) than Dox-treated mice. The IHC analysis of keratin 1 (K1), the receptor for peptide 18-4, revealed K1 upregulation in tumors and low levels in normal mammary fat pad and liver tissues from mice, suggesting preferential uptake of PDCs by TNBC to be K1 receptor-mediated. Taken together, our data support the use of a PDC approach to deliver chemotherapy selectively to the TNBC to inhibit tumor growth.
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Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Feminino , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Queratina-1 , Sistemas de Liberação de Medicamentos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Peptídeos/uso terapêutico , Linhagem Celular Tumoral , Neoplasias da Mama/tratamento farmacológicoRESUMO
The present study was conducted to utilize the commonly discarded pea processing industrial waste (pea pods) for the development of popularly consumed food as cookies. Sweet and salted cookies were prepared by substituting refined and whole wheat flour with pea pod powder at the levels of 5%, 10%, 15% and 20%. The effect of incorporation of pea pod powder on pasting properties of flour, dough characteristics, physical properties and organoleptic attributes of cookies was studied. With the increase in the level of incorporation of pea peel to wheat flour, water absorption capacity increases by 11-14% and dough development time by 1.8 to 2.3 min but decreased final viscosity by 39-49% and dough stability time by 3 min. Addition of pea peel powder to wheat flour improved the physical properties of cookies. On the basis of organoleptic score and physical properties, 10% substitution of whole wheat flour with pea peel powder was accepted. Addition of 10% pea peel powder to the cookies increased fiber content by 49%, insoluble fiber by 118% and soluble fiber by 77.5%. The optimized sweet and salty cookies were packed in different packaging materials and were stored at ambient conditions for 4 months. Cookies packed in aluminum laminate had shelf life beyond 4 months than other packaging materials. The cookies were organoleptically acceptable among the consumers and were rich in fiber. Thus, pea processing waste could be utilized as an ingredient for the development of nutritionally enriched cheap food products. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05780-6.
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Crop diseases cause the release of volatiles. Here, the use of an SnO2-based chemoresistive sensor for early diagnosis has been attempted. Ionone is one of the signature volatiles released by the enzymatic and nonenzymatic cleavage of carotene at the latent stage of some biotic stresses. To our knowledge, this is the first attempt at sensing volatiles with multiple oxidation sites, i.e., ionone (4 oxidation sites), from the phytovolatile library, to derive stronger signals at minimum concentrations. Further, the sensitivity was enhanced on an interdigitated electrode by the addition of platinum as the dopant for a favorable space charge layer and for surface island formation for reactive interface sites. The mechanistic influence of oxygen vacancy formation was studied through detailed density functional theory (DFT) calculations and reactive oxygen-assisted enhanced binding through X-ray photoelectron spectroscopy (XPS) analysis.
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Idioma , Norisoprenoides , Eletrodos , Fazendas , OxigênioRESUMO
ABSTACTAim: The present study aimed to investigate the effect of rose sirup and marigold powder on the physicochemical properties, bioactive potential, sensory acceptability and storage life of the nutricereals (finger millet, oats) and milk-based functional beverage (FB).Method: Preliminary trials were performed using different levels of rose sirup (8-14%) and marigold powder (0.40-0.55%) in the pre-standardized FB. The most acceptable concentration was selected on the basis of sensory analysis. Selected beverages were then subjected to the physicochemical analysis, assessment of bioactive compounds and FTIR characterization. The effect of flower extracts on the mineral content and storage life (4 ± 1 °C) of beverages was also studied. The significant difference in treatments was determined using Duncan's multiple range test, SPSS 25.0.Results: The best acceptable concentrations for rose sirup and marigold powder were 10% and 0.50%, respectively. A significant (p ≤ 0.05) decrease in the dietary fiber (6.50%) and ß-glucan (3.95%) content was observed on the addition of rose sirup. Significant (p ≤ 0.05) increase in the total phenols (119.18-145.23%), ß-carotene (0.37%), anthocyanins (78.82-230.58%) and antioxidant activity (4.98-7.17%) was observed on the addition of flower extracts. Strong peaks were observed in the regions of 3600-3200, 3000-2800 and 1700-1600 cm - 1 on FTIR characterization. A significant decrease in the mineral content of FB was also found on the addition of rose sirup. Rose flavored beverage had the highest overall acceptability (7.83 ± 0.23) and storage stability (50 days at refrigerated storage) among the prepared beverages.Conclusion: The addition of flower extracts significantly improved the acceptability of the prepared beverages. It not only improved the phytochemical profile but also had a substantial impact on storage stability.
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Rosa , Animais , Antocianinas , Bebidas/análise , Humanos , Leite , Compostos Fitoquímicos , PósRESUMO
Mannheimia haemolytica-induced bovine respiratory disease causes loss of millions of dollars to Canadian cattle industry. Current antimicrobials are proving to be ineffective and leave residues in meat. Antimicrobial peptides (AMPs) may be effective against M. haemolytica while minimizing the risk of drug residues. Cationic AMPs can kill bacteria through interactions with the anionic bacterial membrane. Human ß-Defensin 3 (HBD3) and microcin J25 (MccJ25) are AMPs with potent activity against many Gram-negative bacteria. We tested the microbicidal activity of wild-type HBD3, three HBD3 peptide analogues (28 amino acid, 20AA, and 10AA) derived from the sequence of natural HBD3, and MccJ25 in vitro against M. haemolytica. Three C-terminal analogues of HBD3 with all cysteines replaced with valines were manually synthesized using solid phase peptide synthesis. Since AMPs can act as chemoattractant we tested the chemotactic effect of HBD3, 28AA, 20AA, and 10AA peptides on bovine neutrophils in Boyden chamber. Minimum bactericidal concentration (MBC) assay showed that M. haemolytica was intermediately sensitive to HBD3, 28AA and 20AA analogues with an MBC of 50 µg/mL. The 10AA analogue had MBC 6.3 µg/mL which is likely a result of lower final inoculum size. MccJ25 didn't have significant bactericidal effect below an MBC < 100 µg/mL. Bovine neutrophils showed chemotaxis towards HBD3 and 20AA peptides (P < 0.05) but not towards 28AA analogue. Co-incubation of neutrophils with any of the peptides did not affect their chemotaxis towards N-formyl-L-methionyl-L-leucyl-phenylalanine (fMLP). The data show that these peptides are effective against M. haemolytica and are chemotactic for neutrophils in vitro.
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Bacteriocinas/farmacologia , Mannheimia haemolytica/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , beta-Defensinas/genética , beta-Defensinas/farmacologia , Animais , Bacteriocinas/genética , Bacteriocinas/metabolismo , Bovinos , Mannheimia haemolytica/fisiologia , Neutrófilos/fisiologia , Engenharia de Proteínas , beta-Defensinas/metabolismoRESUMO
To achieve the nutritional target of human food, boron (B) has been described as an essential mineral in determining seed and theoretical oil yield of Sesamum indicum L. The research to increase its cultivation is garnering attention due to its high oil content, quality and its utilization for various purposes, which include human nutrition as well as its use in the food industry. For this, a two-year field experiment was performed at PAU, Punjab, India to determine the effect of different concentrations of foliar-applied B (20, 30 and 40 mg L-1) and different growth stages of crop, i.e., we measured the effects on agroeconomic indicators and certain quality parameters of sesame using different concentrations of B applied at the flowering and capsule formation stages as compared to using water spray and untreated plants. Water spray did not significantly affect the studied parameters. However, B application significantly increased the yield, uptake, antioxidant activity (AOA) and theoretical oil content (TOC) compared to those of untreated plants. The maximum increase in seed yield (26.75%), B seed and stover uptake (64.08% and 69.25%, respectively) as well as highest AOA (69.41%) and benefit to cost ratio (B:C ratio 2.63) was recorded when B was applied at 30 mg L-1 at the flowering and capsule formation stages. However, the maximum sesame yield and B uptake were recorded when B was applied at a rate of 30 mg L-1. A significant increase in TOC was also recorded with a B application rate of 30 mg L-1. For efficiency indices, the higher values of boron agronomic efficiency (BAE) and boron crop recovery efficiency (BCRE) were recorded when B was applied at 20 mg L-1 (5.25 and 30.56, respectively) and 30 mg L-1 (4.96 and 26.11, respectively) at the flowering and capsule formation stages. In conclusion, application of B @ 30 mg L-1 at the flowering and capsule formation stages seemed a viable technique to enhance yield, B uptake and economic returns of sesame.
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Agricultura/economia , Boro/metabolismo , Desenvolvimento Vegetal , Sesamum/crescimento & desenvolvimento , Sesamum/metabolismo , Algoritmos , Fenômenos Químicos , Minerais , Modelos Econômicos , Modelos Teóricos , Óleo de Gergelim/análise , Óleo de Gergelim/químicaRESUMO
In this study purees were prepared from the three different varieties of sweet pepper (red var. Inspiration, yellow var. Bachata and green var. Indra). The effect of storage on the chemical [water activity, pH, non-enzymatic browning (NEB) index and color], bioactive (total phenols, flavonoids, antioxidant activity, ascorbic acid and carotenoids) and microbiological (total plate count and mold yeast count) quality of the purees were observed at the interval of 15 days for 75 days. Antioxidant activity of purees was assessed in terms of DPPH, metal chelating activity and reducing power assay. The non-significant (p < 0.05) changes were observed in the water activity and pH of purees upto 30 days of storage. The NEB index was high in green puree as compared to the others at the end of storage period.There was minor change in the color of purees during storage. Bioactive compounds retention was higher in red (90%) followed by yellow (82%) and green (70%) sweet pepper puree. The purees had microbial stability after the 75 days of storage. This study suggests that shelf life of sweet peppers can be enhanced in the form of purees with maximum retention of bioactive compounds.
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Biofortified (PBW 1 Zn) wheat flour was fractionated into three fractions (355, 180 and 150 µm) and evaluated for physicochemical, functional, rheological, biochemical and chapatti making parameters. With decreasing flour particle size the ash, fat, fibre, phytic acid, antioxidant activity, total phenolic content and pasting properties decreased, whereas carbohydrates, zinc, lightness (L*) and functional parameters increased. Chapatti making quality of flour fraction (180 µm) was observed best on the basis of puffing height (7.64 cm), extensibility (1.83 N) and sensory quality with best overall sensory scores (8.75). The results indicate that reducing the particle size to 180 µm could improve the nutritional, functional and chapatti making quality of wheat flour.
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Sweet pepper purees (red, yellow and green) were examined for FTIR (Fourier-transform infrared spectroscopy), chemical, bioactive, color and rheological parameters. FTIR technique was used to evaluate the functional groups. FTIR wave numbers are associated with the absorption bands that depicted the presence of several phytocompounds in the purees. Among the chemical parameters, water activity varied non-significantly whereas, total soluble sugars (TSS), sugars and pH increased after processing of the fruits into purees. The presence of bioactive compounds depends on the variety of sweet pepper. The red puree had significantly higher carotenoids, phenolics and antioxidant capacity followed by yellow and green pepper purees. The minimal change was observed in the color of purees during processing. The purees were subjected to different shear rate (1 to 50 s-1) to evaluate the effect on viscosity and shear stress that is desirable for its end use in different food products. All purees show the shear thinning behavior as shear rate increased. Results revealed that heat processing of sweet peppers didn't affect color, sugars, carotenoids, phenolics and antioxidant capacity to a greater extent. The finding will be helpful to manage seasonal bulk production efficiently and make them available as an ingredient in various food products.
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Capsicum , Carotenoides , Cor , Frutas , ReologiaRESUMO
The effect of potassium nitrate on the status of fermentative and sucrose metabolizing pathways was studied in two maize (Zea mays L.) genotypes, viz., LM 5 (relatively susceptible to flooding) and I 167 (relatively tolerant to flooding) under water logging stress. The higher increase in pyruvate decarboxylase, alcohol dehydrogenase and aldehyde dehydrogenase activities in the hypoxic roots of I 167 seedlings over LM 5 showed the former's efficient tolerance mechanism towards anaerobic conditions. Foliar application of KNO3 reduced these enzymatic activities in the roots of both the genotypes. The shoots of I 167 seedlings also showed a parallel increase in alcohol dehydrogenase and pyruvate decarboxylase activities under water logging stress. These enzymatic activities, however, remained unaffected in shoots of water logged LM 5 seedlings. There was a higher decrease in acid and alkaline invertase activities in the hypoxic roots of I 167 seedlings. KNO3 treatment led to higher acid invertase activity in roots of I 167 seedlings than those of LM 5. Sucrose synthase (synthesis) and sucrose phosphate synthase activities decreased, but sucrose synthase (breakdown) activity increased in the roots of both the genotypes, during water logging. KNO3 increased sucrose synthesizing activities with a parallel increase in the sucrose content of the roots. Sucrose synthesis was comparatively unaffected in I 167 shoots under water logging stress while LM 5 shoots showed higher reduction in its sucrose synthase (synthesis) and sucrose phosphate synthase activities. It may thus be concluded that KNO3 induced a network of reactions for improving water logging tolerance. The nitrate ions acted as an alternate electron acceptor and thus reduced the activities of fermentative enzymes. It promoted the funneling of sugars into the glycolytic pathway by inducing the activities of acid and alkaline invertases in the roots and shoots of maize genotypes. It also directed the hexoses towards biosynthetic pathway by increasing the activities of sucrose synthesizing enzymes.
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The research study was conducted to utilize by-products of baby corn in the development of soup mix. Baby corn powder was obtained by drying and grinding of cut pieces of baby corn. Different formulations of soup mixes were prepared by altering the level of baby corn powder (10-40%), corn flour, salt, mango, onion, garlic, cumin, black pepper, coriander and sugar powders. Formulation 2-baby corn powder:corn flour:onion powder:garlic powder:salt:sugar:mango powder:coriander powder:cumin powder:black pepper in ratio of 20:42:2:2:10:6:15:1:1:1 was selected best on the basis of proximate, functional, pasting and sensory parameters. Soup mix was stored under ambient conditions and a declining trend was observed for antioxidant activity (67.64-48.41% DPPH inhibition), water absorption index (3.15-2.58 g/g), pH (6.81-4.15) and sensory score whereas total plate count, moisture and viscosity were found increasing after every 15 days interval. After 5 months of storage, color and sensory parameters declined. This study is valuable in promoting exploitation of by-products of baby corn by preparing soup mix that can alleviate the problem of postharvest losses and by-product utilization.
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Microencapsulated α-tocopherol and wheat germ oil (WGO) were incorporated as WGO (5.0 ml) in liquid: WGO-L, encapsulated: WGO-E, encapsulated α-tocopherol as E1, E2 and E3 at 2.0, 3.0 and 4.0 g respectively in cookies and evaluated for physical, sensory and shelf life parameters. Spread ratio was decreased, whereas hardness was increased with encapsulated formulations and observed least in WGO-L (40.52 N) formulated cookies. During storage moisture content was observed increased (2.51-4.78%), vitamin E was retained in all formulations except WGO-L and was found maximum in E3 (4.45 mg/100 g) formulated cookies. Formulations brought the peroxide value to nil, free fatty acid development was very less, better antioxidant activity (41.1% maximum), total plate count was observed least in E3 (25 × 102 cfu/g) and good sensory acceptance of cookies up to 4 months of storage. The study concluded that encapsulated vitamin E elevated the antioxidant activity and consequently shelf life and nutritive value of cookies.
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In this study, we have designed and synthesized two novel peptide-drug conjugates (PDCs) where the drug, doxorubicin (Dox), is linked to the peptide via a succinimidyl thioether bond or a hydrazone linker. A highly specific and proteolytically stable breast cancer cell targeting peptide (WxEAAYQrFL) is conjugated to Dox to synthesize peptide-Dox thioether (1) or hydrazone (2) conjugate. The evaluation of the stability in water, media, and human serum showed that the conjugate 1 with the succinimidyl thioether linkage is more stable compared to the acid-sensitive hydrazone containing conjugate 2. The cytotoxicity studies showed that the two PDCs were as toxic as free Dox toward the triple negative breast cancer (TNBC) cells and were 7-30 times less toxic (IC50 1.2-4.7 µM for TNBC cells versus 15-39 µM for noncancerous cells) toward the noncancerous breast cells compared to the free doxorubicin (IC50 0.35-1.5 µM for TNBC cells versus 0.24 µM for noncancerous cells). The results from the comparative study of the two PDCs suggest that both may have translational potential for TNBC treatment.
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Doxorrubicina/química , Peptídeos/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Reagentes de Ligações Cruzadas/química , Reagentes de Ligações Cruzadas/farmacologia , Citotoxinas/química , Citotoxinas/toxicidade , Humanos , Hidrazonas , SulfetosRESUMO
The present study was undertaken to study the effect of osmo priming on sucrose metabolism of spring maize, under limited irrigation conditions. Osmo priming increased the activities of acid invertase, alkaline invertase and sucrose synthase (cleavage) and the contents of reducing sugars and starch in the grains of stressed plants. There was also an increase in sucrose phosphate synthase activity with a parallel increase in sucrose content in leaves of stressed plants in comparison with those of hydro priming treatment. It showed that osmo priming helped in improving sucrose phosphate synthase activity in leaves of plants, leading to higher sucrose content, under stress conditions.
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Purpose Achieving successful gene therapy requires delivery of a gene vector specifically to the targeted tissue with efficient expression and a good safety profile. The objective of this work was to develop, characterize and determine if a novel gemini surfactant-based lipoplex systems, modified with a cancer-targeting peptide p18-4, could serve this role. Methods The targeting peptide p18-4 was either chemically coupled to a gemini surfactant backbone or physically co-formulated with the lipoplexes. The influence of targeting ligand and formulation strategies on essential physicochemical properties of the lipoplexes was evaluated by dynamic light scattering and small angle X-ray scattering techniques. In vitro transfection activity and cellular toxicity of lipoplexes were assessed in a model human melanoma cell line. Results All lipoplexes zeta potential and particle size were optimal for cellular uptake and physical stability of the system. The lipoplexes adopted an inverted-hexagonal lipid arrangement. The lipoplexes modified with the peptide showed no significant changes in physicochemical properties or lipoplex assembly. The modification of the lipoplexes with the targeting peptide significantly enhanced protein expression 2-6 fold compared to non-modified lipoplexes. In addition, p18-4 modified lipoplexes significantly improved the safety of the lipoplexes. The ability of the p18-4 modified lipoplexes to selectively express the model protein was confirmed by using healthy human epidermal keratinocytes (HEKa). Conclusion The gemini surfactant-based lipoplexes modified with p18-4 peptide showed significantly higher efficiency and safety compared to the system that did not contain a cancer targeting peptide and provided evidence for their potential application to achieve targeted melanoma gene therapy.
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Antineoplásicos/farmacologia , Terapia Genética , Lipídeos/química , Melanoma/tratamento farmacológico , Modelos Biológicos , Peptídeos/farmacologia , Tensoativos/química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Melanoma/patologia , Estrutura Molecular , Tamanho da Partícula , Peptídeos/química , Propriedades de Superfície , Células Tumorais CultivadasRESUMO
α-Tocopherol is a well-known fat-soluble antioxidant and is widely used in the food industry for stabilizing free radicals. Incorporation and stability of it into food is another challenge as directly added α-tocopherol is prone to inactivation by food constituents. This study was aimed at optimizing conditions for encapsulation of α-tocopherol using combination of sodium alginate (0.5, 1.0, 1.5 and 2.0%) as primary wall material and pectin (2.0%) as filler. The optimum conditions were selected on the basis of encapsulation efficiency, shape, size, bulk density, yield and swelling index with syringe method. The encapsulation efficiency of α-tocopherol in microencapsules produced under optimal conditions was 52.91% using sodium alginate 1.5% w/v and pectin 2.0% w/v. α-Tocopherol was encapsulated with encapsulator using standard conditions and was compared with syringe method. The encapsulation efficiency was found more (55.97%) in microencapsules prepared with encapsulator and 52.11% in microencapsules prepared with syringe.
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BACKGROUND: Neuroinflammation in the brain consequent to activation of microglia is viewed as an important component of Alzheimer's disease (AD) pathology. Amyloid beta (Aß) protein is known to activate microglia and unleash an inflammatory cascade that eventually results in neuronal dysfunction and death. In this study, we sought to identify the presence of amylin receptors on human fetal and murine microglia and determine whether Aß activation of the inflammasome complex and subsequent release of cytokines is mediated through these receptors. METHODS: The presence of dimeric components of the amylin receptor (calcitonin receptor and receptor activity modifying protein 3) were first immunohistochemically identified on microglia. Purified human fetal microglial (HFM) cultures were incubated with an in vivo microglial marker, DyLight 594-conjugated tomato lectin, and loaded with the membrane-permeant green fluorescent dye, Fluo-8L-AM for measurements of intracellular calcium [Ca2+]i. HFM and BV-2 cells were primed with lipopolysaccharide and then exposed to either human amylin or soluble oligomeric Aß1-42 prior to treatment with and without the amylin receptor antagonist, AC253. Changes in the inflammasome complex, NLRP3 and caspase-1, were examined in treated cell cultures with Western blot and fluorometric assays. RT-PCR measurements were performed to assess cytokine release. Finally, in vivo studies were performed in transgenic mouse model of AD (5xFAD) to examine the effects of systemic administration of AC253 on markers of neuroinflammation in the brain. RESULTS: Acute applications of human amylin or Aß1-42 resulted in an increase in [Ca2+]i that could be blocked by the amylin receptor antagonist, AC253. Activation of the NLRP3 and caspase-1 and subsequent release of cytokines, TNFα and IL-1ß, was diminished by AC253 pretreatment of HFMs and BV2 cells. In vivo, intraperitoneal administration of AC253 resulted in a reduction in microglial markers (Iba-1 and CD68), caspase-1, TNFα, and IL-1ß. These reductions in inflammatory markers were accompanied by reduction in amyloid plaque and size in the brains of 5xFAD mice compared to controls. CONCLUSION: Microglial amylin receptors mediate Aß-evoked inflammation, and amylin receptor antagonists therefore offer an attractive therapeutic target for intervention in AD.
Assuntos
Peptídeos beta-Amiloides/toxicidade , Inflamação/induzido quimicamente , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fragmentos de Peptídeos/toxicidade , Receptores de Polipeptídeo Amiloide de Ilhotas Pancreáticas/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Animais , Caspase 1/metabolismo , Linhagem Celular Transformada , Células Cultivadas , AMP Cíclico/metabolismo , Citocinas/genética , Citocinas/metabolismo , Feminino , Feto/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Humanos , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Transgênicos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêuticoRESUMO
The biomarkers or receptors expressed on cancer cells and the targeting ligands with high binding affinity for biomarkers play a key role in early detection and treatment of breast cancer. The breast cancer targeting peptide p160 (12-mer) and its enzymatically stable analogue 18-4 (10-mer) showed marked potential for breast cancer drug delivery using cell studies and animal models. Herein, we used affinity purification, liquid chromatography-tandem mass spectrometry, and proteomics to identify keratin 1 (KRT1) as the target receptor highly expressed on breast cancer cells for p160 peptide(s). Western blot and immunocytochemistry in MCF-7 breast cancer cells confirmed the identity of KRT1. We demonstrate that the p160 or 18-4 binding to MCF-7 breast cancer cells is dependent on the expression of KRT1, and we confirm peptide-KRT1 binding specificity using SPR experiments (Kd â¼ 1.1 µM and 0.98 µM for p160 and 18-4, respectively). Furthermore, we assessed the ability of peptide 18-4 to improve the cellular uptake and anticancer activity of a pro-apoptotic antimicrobial peptide, microcin J25 (MccJ25), in breast cancer cells. A covalent conjugate of peptide 18-4 with MccJ25 showed preferential cytotoxicity toward breast cancer cells with minimal cytotoxicity against normal HUVEC cells. The conjugate inhibited the growth of MDA-MB-435 MDR multidrug-resistant cells with an IC50 comparable to that of nonresistant cells. Conjugation improved selective cellular uptake of MccJ25, and the conjugate triggered cancer cell death by apoptosis. Our findings establish KRT1 as a new marker for breast cancer targeting. Additionally, it pinpoints the potential use of antimicrobial lasso peptides as a novel class of anticancer therapeutics.