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1.
Physiol Plant ; 176(2): e14260, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511471

RESUMO

Bacosides are dammarane-type triterpenoidal saponins in Bacopa monnieri and have various pharmacological applications. All the bacosides are diversified from two isomers, i.e., jujubogenin and pseudojujubogenin. The biosynthetic pathway of bacoside is not well elucidated. In the present study, we characterized a UDP-glycosyltransferase, UGT79A18, involved in the glycosylation of pseudojujubogenin. UGT79A18 shows higher expression in response to 5 h of wounding, and 3 h of MeJA treatment. The recombinant UGT79A18 shows in vitro activity against a wide range of flavonoids and triterpenes and has a substrate preference for protopanaxadiol, a dammarane-type triterpene. Secondary metabolite analysis of overexpression and knockdown lines of UGT79A18 in B. monnieri identify bacopasaponin D, bacopaside II, bacopaside N2 and pseudojujubogenin glucosyl rhamnoside as the major bacosides that were differentially accumulated. In the overexpression lines of UGT79A18, we found 1.7-fold enhanced bacopaside II, 8-fold enhanced bacopasaponin D, 3-fold enhanced pseudojujubogenin glucosyl rhamnoside, and 1.6-fold enhanced bacopaside N2 content in comparison with vector control plant, whereas in the knockdown lines of UGT79A18, we found 1.4-fold reduction in bacopaside II content, 3-fold reduction in the bacopasaponin D content, 2-fold reduction in the pseudojujubogenin glucosyl rhamnoside content, and 1.5-fold reduction in bacopaside N2 content in comparison with vector control. These results suggest that UGT79A18 is a significant UDP glycosyltransferase involved in glycosylating pseudojujubogenin and enhancing the pseudojujubogenin-derived bacosides.


Assuntos
Acetatos , Bacopa , Ciclopentanos , Oxilipinas , Saponinas , Triterpenos , Bacopa/genética , Bacopa/química , Glicosiltransferases/genética , Vias Biossintéticas , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/uso terapêutico , 60630 , Difosfato de Uridina , Extratos Vegetais/química
2.
Cancers (Basel) ; 16(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38339390

RESUMO

Heat shock proteins (HSPs) are developmentally conserved families of protein found in both prokaryotic and eukaryotic organisms. HSPs are engaged in a diverse range of physiological processes, including molecular chaperone activity to assist the initial protein folding or promote the unfolding and refolding of misfolded intermediates to acquire the normal or native conformation and its translocation and prevent protein aggregation as well as in immunity, apoptosis, and autophagy. These molecular chaperonins are classified into various families according to their molecular size or weight, encompassing small HSPs (e.g., HSP10 and HSP27), HSP40, HSP60, HSP70, HSP90, and the category of large HSPs that include HSP100 and ClpB proteins. The overexpression of HSPs is induced to counteract cell stress at elevated levels in a variety of solid tumors, including anticancer chemotherapy, and is closely related to a worse prognosis and therapeutic resistance to cancer cells. HSPs are also involved in anti-apoptotic properties and are associated with processes of cancer progression and development, such as metastasis, invasion, and cell proliferation. This review outlines the previously mentioned HSPs and their significant involvement in diverse mechanisms of tumor advancement and metastasis, as well as their contribution to identifying potential targets for therapeutic interventions.

3.
Toxicol Ind Health ; 40(1-2): 1-8, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37876040

RESUMO

Synthetic cosmetics, particularly hair dyes, are becoming increasingly popular among people of all ages and genders. 2,4,5,6-tetraaminopyrimidine sulfate (TAPS) is a key component of oxidative hair dyes and is used as a developer in several hair dyes. TAPS has previously been shown to absorb UVB strongly and degrade in a time-dependent manner, causing phototoxicity in human skin cells. However, the toxic effects of UVB-degraded TAPS are not explored in comparison to parent TAPS. Therefore, this research work aims to assess the toxicity of UVB-degraded TAPS than TAPS on two different test systems, that is, HaCaT (mammalian cell) and Staphylococcus aureus (a bacterial cell). Our result on HaCaT has illustrated that UVB-degraded TAPS is less toxic than parent TAPS. Additionally, UVB-exposed TAPS and parent TAPS were given to S. aureus, and the bacterial growth and their metabolic activity were assessed via CFU and phenotype microarray. The findings demonstrated that parent TAPS reduced bacterial growth via decreased metabolic activity; however, bacteria easily utilized the degraded TAPS. Thus, this study suggests that the products generated after UVB irradiation of TAPS is considered to be safer than their parent TAPS.


Assuntos
Tinturas para Cabelo , Feminino , Masculino , Animais , Humanos , Tinturas para Cabelo/toxicidade , Tinturas para Cabelo/metabolismo , Sulfatos/toxicidade , Staphylococcus aureus , Pele , Cabelo , Raios Ultravioleta/efeitos adversos , Queratinócitos/metabolismo , Mamíferos
4.
Ecotoxicol Environ Saf ; 269: 115783, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38061081

RESUMO

Symbiotic interactions play a vital role in maintaining the phosphate (Pi) nutrient status of host plants and providing resilience during biotic and abiotic stresses. Serendipita indica, a mycorrhiza-like fungus, supports plant growth by transporting Pi to the plant. Despite the competitive behaviour of arsenate (AsV) with Pi, the association with S. indica promotes plant growth under arsenic (As) stress by reducing As bioavailability through adsorption, accumulation, and precipitation within the fungus. However, the capacity of S. indica to enhance Pi accumulation and utilization under As stress remains unexplored. Axenic studies revealed that As supply significantly reduces intracellular ACPase activity in S. indica, while extracellular ACPase remains unaffected. Further investigations using Native PAGE and gene expression studies confirmed that intracellular ACPase (isoform2) is sensitive to As, whereas extracellular ACPase (isoform1) is As-insensitive. Biochemical analysis showed that ACPase (isoform1) has a Km of 0.5977 µM and Vmax of 0.1945 Unit/min. In hydroponically cultured tomato seedlings, simultaneous inoculation of S. indica with As on the 14thday after seed germination led to hyper-colonization, increased root/shoot length, biomass, and induction of ACPase expression and secretion under As stress. Arsenic-treated S. indica colonized groups (13.33 µM As+Si and 26.67 µM As+Si) exhibited 8.28-19.14 and 1.71-3.45-fold activation of ACPase in both rhizospheric media and root samples, respectively, thereby enhancing Pi availability in the surrounding medium under As stress. Moreover, S. indica (13.33 µM As+Si and 26.67 µM As+Si) significantly improved Pi accumulation in roots by 7.26 and 9.46 times and in shoots by 4.36 and 8.85 times compared to the control. Additionally, S. indica induced the expression of SiPT under As stress, further improving Pi mobilization. Notably, fungal colonization also restricted As mobilization from the hydroponic medium to the shoot, with a higher amount of As (191.01 ppm As in the 26.67 µM As+Si group) accumulating in the plant's roots. The study demonstrates the performance of S. indica under As stress in enhancing Pi mobilization while limiting As uptake in the host plant. These findings provide the first evidence of the As-Pi interaction in the AM-like fungus S. indica, indicating reduced As uptake and regulation of PHO genes (ACPase and SiPT genes) to increase Pi acquisition. These data also lay the foundation for the rational use of S. indica in agricultural practices.


Assuntos
Fosfatase Ácida , Arsênio , Basidiomycota , Micorrizas , Arsênio/toxicidade , Arsênio/metabolismo , Basidiomycota/metabolismo , Micorrizas/fisiologia , Fosfatos/farmacologia , Fosfatos/metabolismo , Raízes de Plantas/metabolismo , Fosfatase Ácida/metabolismo , Fosfatase Ácida/farmacologia
5.
Biomater Adv ; 157: 213729, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38101068

RESUMO

Bioactive glasses have recently been attracted to meet the challenge in bone tissue regeneration, repair, healing, dental implants, etc. Among the conventional bio-glasses, a novel quaternary mesoporous nano bio-glass with composition 81S(81SiO2-(16-x)CaO-2P2O5-1Na2O-xMgO) (x = 0, 1.6, 2.4, 4 and 8 mol%) employing Stober's method has been explored for examining the above potential application through in-vitro SBF assay, MTT assay, antimicrobial activity and drug loading and release ability. With increasing the MgO concentration up to 4 mol%, from in-vitro SBF assay, we observe that HAp layer develops on the surface of the nBGs confirmed from XRD, FTIR and FESEM. MTT assay using MG-63 cells confirms the biocompatibility of the nBGs having cell viability >225 % for MGO_4 after 72 h which is more than the clinically used 45S5 bio-glass. We have observed cell viability of >125 % even after 168 h. Moreover, MGO_4 is found to restrict the growth of E. coli by 65 % while S. aureus by 75 %, confirming the antimicrobial activity. Despite an increase in the concentration of magnesium, nBGs are found to be non-toxic towards the RBCs up to 4 mol% of MgO while for 8 %, the hemolysis percentage is >6 % which is toxic. Being confirmed MGO_4 nBG as a bioactive material, various concentrations of drug (Dexamethasone (DEX)) loading and release kinetics are examined. We show that 80 % of loading in case of 10 mg-ml-1 and 70 % of cumulative release in 100 h. The mesoporous structure of MGO_4 having an average pore diameter of 5 nm and surface area of 216 m2 g-1 confirmed from BET supports the loading and release kinetics. We conclude that the quaternary MGO_4 nBG may be employed effectively for bone tissue regeneration due to its high biocompatibility, excellent in-vitro cell viability, antimicrobial response and protracted drug release.


Assuntos
Anti-Infecciosos , Óxido de Magnésio , Óxido de Magnésio/farmacologia , Óxido de Magnésio/química , Escherichia coli , Staphylococcus aureus , Anti-Infecciosos/farmacologia , Vidro/química
6.
Biomedicines ; 11(10)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37893013

RESUMO

The development of multidrug resistance (MDR) against chemotherapeutic agents has become a major impediment in cancer therapy. Understanding the underlying mechanism behind MDR can guide future treatment for cancer with better therapeutic outcomes. Recent studies evidenced that crossroads interaction between the heat shock proteins (HSP) and inflammatory responses under the tumor microenvironment plays a pivotal role in modulating drug responsiveness and drug resistance through a complex cytological process. This review aims to investigate the interrelationship between inflammation and HSP in acquiring multiple drug resistance and investigate strategies to overcome the drug resistance to improve the efficacy of cancer treatment. HSP plays a dual regulatory effect as an immunosuppressive and immunostimulatory agent, involving the simultaneous blockade of multiple signaling pathways in acquiring MDR. For example, HSP27 shows biological effects on monocytes by causing IL10 and TNFα secretion and blocking monocyte differentiation to normal dendritic cells and tumor-associated macrophages to promote cancer progression and chemoresistance. Thus, the HSP function and immune-checkpoint release modalities provide a therapeutic target for a therapeutically beneficial approach for enhancing anti-tumor immune responses. The interconnection between inflammation and HSP, along with the tumor microenvironment in acquiring drug resistance, has become crucial for rationalizing the effect of HSP immunomodulatory activity with immune checkpoint blockade. This relationship can overcome drug resistance and assist in the development of novel combinatorial cancer immunotherapy in fighting cancer with decreasing mortality rates.

7.
Nanotechnology ; 34(42)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37402363

RESUMO

CoMn2O4, known for its extensive range of applications, has been subject to limited investigations regarding its structure dependent magnetic properties. Here, we have examined the structure dependent magnetic properties of CoMn2O4nanoparticles synthesized through a facile coprecipitation technique and are characterized using x-ray diffractometer, x-ray photoelectron spectroscopy (XPS), RAMAN spectroscopy, transmission electron microscopy and magnetic measurements. Rietveld refinement of the x-ray diffraction pattern reveals the coexistence of 91.84% of tetragonal and 8.16% of cubic phase. The cation distribution for tetragonal and cubic phases are (Co0.94Mn0.06)[Co0.06Mn1.94]O4and (Co0.04Mn0.96)[Co0.96Mn1.04]O4, respectively. While Raman spectra and selected area electron diffraction pattern confirm the spinel structure, both +2 and +3 oxidation states for Co and Mn confirmed by XPS further corroborate the cation distribution. Magnetic measurement shows two magnetic transitions, Tc1at 165 K and Tc2at 93 K corresponding to paramagnetic to a lower magnetically ordered ferrimagnetic state followed by a higher magnetically ordered ferrimagnetic state, respectively. While Tc1is attributed to the cubic phase having inverse spinel structure, Tc2corresponds to the tetragonal phase with normal spinel. In contrast to general temperature dependentHCobserved in ferrimagnetic material, an unusual temperature dependentHCwith high spontaneous exchange bias of 2.971 kOe and conventional exchange bias of 3.316 kOe at 50 K are observed. Interestingly, a high vertical magnetization shift (VMS) of 2.5 emu g-1is observed at 5 K, attributed to the Yafet-Kittel spin structure of Mn3+in the octahedral site. Such unusual results are discussed on the basis of competition between the non-collinear triangular spin canting configuration of Mn3+cations of octahedral sites and collinear spins of tetrahedral site. The observed VMS has the potential to revolutionize the future of ultrahigh density magnetic recording technology.

8.
Environ Monit Assess ; 192(11): 680, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33025180

RESUMO

In this study, the activities of 40K, 210Pb, 232Th, 234U, 235U, and 238U in size-segregated particulate matter (PM) were measured in the Singrauli Coalfield, India. Different isotopic compositions were found relative to natural uranium ratios. The radioactivity concentration ratios in different PM sizes [PM2.5, PM10, and suspended particulate matter (SPM)] suggested that anthropogenic sources affected the uranium isotopic compositions in the area. A different isotopic composition from the natural uranium composition was found. The correlation coefficients between the measured isotopes (40K, 210Pb, 232Th, 234U, 235U, and 238U) and meteorological factors were calculated. PM emissions were affected by the meteorological conditions, which in turn, influenced the U and Th concentrations in PM. The 232Th/238U activity ratio in particulate matter was between 0.20 and 1.54 with an average value of 0.9 ± 0.5, 0.2 to 1.1 (0.8 ± 0.7), and 0.2 to 1.2 with an average value of 0.8 ± 0.8 in PM2.5, PM10, and SPM, respectively. These range were quite different from the average crustal ratio of 3.5, indicating that the 238U concentrations were elevated in this region relative to Th. However, compared with Th, the dose contribution of U to the public was negligible. The average effective dose in public owing to inhalation of natural radioactive 40K, 210Pb, 232Th, and 234U, 235U, and 238U in the atmosphere was between 0.03 and 327 nSv year-1. These doses associated with the inhalation of particulate matter were lower than world airborne reference value as reported by UNSCEAR (2000a). Graphical abstract.


Assuntos
Neoplasias , Material Particulado , Monitoramento Ambiental , Humanos , Índia , Material Particulado/análise , Radioisótopos
9.
Bioorg Med Chem Lett ; 27(22): 5040-5045, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-29054359

RESUMO

A series of conformationally restricted benzopyran based triarylethylenes has been synthesized and characterized as potential growth inhibitors of breast carcinoma cells. The synthesized compounds (14a-b, 15a and 16a-e) presented significant growth inhibition of ER+ and ER- breast cancer cells within the range of IC50 0.55-9.96µM. Amongst other, 16c showed potent anticancer activity at IC50 0.95µM in MCF-7 cells with good selectivity (Selectivity Index 4.47) towards healthy cells. The mechanistic studies for 16c were performed to elucidate possible mode of action which showed 16c elicited anticancer activity through necroptosis process.


Assuntos
Antineoplásicos/síntese química , Benzopiranos/química , Etilenos/química , Antineoplásicos/química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Benzopiranos/síntese química , Benzopiranos/toxicidade , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células MCF-7 , Conformação Molecular , Receptores de Estrogênio/metabolismo , Relação Estrutura-Atividade
10.
Protoplasma ; 254(1): 389-399, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26971099

RESUMO

The medicinal plant Withania somnifera is researched extensively to increase the quantity of withanolides and specifically withaferin A, which finds implications in many pharmacological activities. Due to insufficient knowledge on biosynthesis and unacceptability of transgenic approach, it is preferred to follow alternative physiological methods to increase the yield of withanolides. Prior use of elicitors like salicylic acid, methyl jasmonate, fungal extracts, and even mechanical wounding have shown to increase the withanolide biosynthesis with limited success; however, the commercial viability and logistics of application are debatable. In this investigation, we tested the simple nitrogeneous fertilizers pertaining to the enhancement of withaferin A biosynthesis. Application of ammonium sulfate improved the sterol contents required for the withanolide biosynthesis and correlated to higher expression of pathway genes like FPPS, SMT1, SMT2, SMO1, SMO2, and ODM. Increased expression of a gene homologous to allene oxide cyclase, crucial in jasmonic acid biosynthetic pathway, suggested the involvement of jasmonate signaling. High levels of WRKY gene transcripts indicated transcriptional regulation of the pathway genes. Increase in transcript level could be correlated with a corresponding increase in the protein levels for WsSMT1 and WsWRKY1. The withaferin A increase was also demonstrated in the potted plants growing in the glasshouse and in the open field. These results implicated simple physiological management of nitrogen fertilizer signal to improve the yield of secondary metabolite through probable involvement of jasmonate signal and WRKY transcription factor for the first time, in W. somnifera besides improving the foliage.


Assuntos
Vias Biossintéticas/genética , Ciclopentanos/metabolismo , Nitrogênio/farmacologia , Oxilipinas/metabolismo , Esteróis/metabolismo , Fatores de Transcrição/metabolismo , Ativação Transcricional/efeitos dos fármacos , Withania/genética , Vitanolídeos/metabolismo , Sulfato de Amônio/farmacologia , Vias Biossintéticas/efeitos dos fármacos , Dimetil Sulfóxido/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Fósforo/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Potássio/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Ureia/farmacologia , Withania/efeitos dos fármacos
11.
J Sep Sci ; 36(14): 2373-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23686893

RESUMO

Vitex trifolia L. is an important Indian medicinal plant with diverse pharmacological properties. In a recent study, we reported the isolation and antitubercular activity evaluation of three new diterpenoids from its leaves; here we have developed a validated rapid, simple, precise, and accurate high-performance TLC method for the simultaneous quantification of isolated diterpenoids in V. trifolia. Diterpenoids, 6α,7α-diacetoxy-13-hydroxy-8(9),14-labdadien (A), 13-hydroxy-5(10),14-halimadien-6-one (B), and 9-hydroxy-13(14)-labden-16,15-olide (C) were separated on silica gel 60F254 high-performance TLC plates using chloroform/acetone (98:2, v/v) as mobile phase. The quantitation of diterpenoids was carried out using densitometric reflection/absorption mode at 610 nm after postchromatographic derivatization using a vanillin/sulfuric acid reagent. A precise and accurate quantification can be performed for compounds A and B in the linear working concentration range of 333-1000 ng/band and for C in the range of 670-2000 ng/band with good correlations (r = 0.9984, 0.9991, and 0.9994, respectively). The method was validated for peak purity, precision, accuracy, robustness, LOD, and LOQ, as per the ICH guidelines. The method reported here is simple, reproducible and may be applied for the quantitative analysis of the above diterpenoids in the leaves of V. trifolia.


Assuntos
Cromatografia em Camada Delgada/métodos , Diterpenos/análise , Extratos Vegetais/análise , Vitex/química , Diterpenos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química
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