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1.
Santolina chamaecyparissus is an important medicinal plant growing in the Mediterranean region and has been reported as a potent anti-inflammatory, antibacterial, antioxidant, and antifungal agent. The purpose of the current research is to identify the chemical constituents in ethyl acetate extract (EAE) from the leaves of S. chamaecyparissus, and to evaluate antidiabetic, and anticancer activity. Chemical constituents of EAE were identified by GC-MS, and the antidiabetic activity was evaluated by α-glucosidase inhibition assay. The anticancer activity was assessed by Epidermal Growth Factor Receptor (EGFR) expression in human breast cancer cell line (MCF7) by using quantitative RT-PCR method. GC-MS analysis of EAE of S. chamaecyparissus yielded 44 compounds. Tetrapentacontane (27.15%), eicosyl acetate (8.40%), 2-methylhexacosane (6.87%), and n-pentadecanol (5.44%) were found as major chemical constituents. The EAE of S. chamaecyparissus showed concentration dependant inhibition of α-glucosidase enzyme and the IC50 value (IC50 110 ± 4.25 µg/mL) was found comparable with standard acarbose (IC50 105 ± 3.74 µg/mL). The real-time qRT-PCR results showed that the EGFR protein (bcl-2) in human breast cancer cell line (MCF7) was negatively expressed with a value of −0.69297105 after treatment with EAE (100 µg/mL). The study results are suggesting the possible use of S. chamaecyparissus in the management of diabetes, and human breast cancer.  相似文献   

2.
In this study, the antioxidant, antimicrobial, genotoxic and anticancer activities of Cetraria islandica methanol extract were determined by using free radical and superoxide anion scavenging activity, reducing power, determination of total phenolic compounds and flavonoid contents, broth microdilution minimal inhibitory concentration against five bacterial and five fungal species, cytokinesis block micronucleus (MN) assay on peripheral blood lymphocytes (PBLs) and the microculture tetrazolium test on FemX (human melanoma) and LS174 (human colon carcinoma) cell lines. As a result of the study, we found that C. islandica methanol extract exhibited moderate free-radical-scavenging activity with IC50 values 678.38 μg/ml. Moreover, the tested extract had effective reducing power and superoxide anion radical scavenging. The minimal inhibitory concentration values against the tested microorganisms ranged from 0.312 to 5 mg/ml. The extract increased MN frequency in a dose dependent manner, but it was significant in higher tested concentrations (50, 100 and 200 μg/ml). No significant differences were observed between NDI values in all treatments and untreated PBLs. In addition, the tested extract had strong anticancer activity towards both cell lines with IC50 values of 22.68 and 33.74 μg/ml. It can be concluded that the tested extract exhibited a certain level of in vitro antioxidant, antimicrobial, genotoxic and anticancer activities.  相似文献   

3.
L-Asparaginase is an antileukemic agent that depletes L-asparagine “an important nutrient for cancer cells” through the hydrolysis of L-asparagine into L-aspartic acid and ammonia leading to leukemia cell starvation and apoptosis in susceptible leukemic cell populations. Moreover currently, bacterial L-asparaginase has been limited by problems of lower productivity, stability, selectivity and a number of toxicities along with the resistance towards bacterial L-asparaginase. Then the current work aimed to provide pure L-asparaginase with in-vitro efficacy against various human carcinomas without adverse effects related to current L-asparaginase formulations. Submerged fermentation (SMF) bioprocess was applied and improved to maximize L-asparaginase production from Fusarium equiseti AHMF4 as alternative sources of bacteria. The enzyme production in SMF was maximized to reach 40.78 U mL−1 at the 7th day of fermentation with initial pH 7.0, incubation temperature 30 °C, 1.0% glucose as carbon source, 0.2% asparagine as nitrogen source, 0.1% alanine as amino acid supplement and 0.1% KH2PO4. The purification of AHMF4 L-asparaginase yielded 2.67-fold purification and 48% recovery with final specific activity of 488.1 U mg−1 of protein. Purified L-asparaginase was characterized as serine protease enzyme with molecular weight of 45.7 kDa beside stability at neutral pH and between 20 and 40 °C. Interestingly, purified L-asparaginase showed promising DPPH radical scavenging activity (IC50 69.12 μg mL−1) and anti-proliferative activity against cervical epitheloid carcinoma (Hela), epidermoid larynx carcinoma (Hep-2), hepatocellular carcinoma (HepG-2), Colorectal carcinoma (HCT-116), and breast adenocarcinoma (MCF-7) with IC50 equal to 2.0, 5.0, 12.40, 8.26 and 22.8 μg mL−1, respectively. The enzyme showed higher activity, selectivity and anti-proliferative activity against cancerous cells along with tiny cytotoxicity toward normal cells (WI-38) which indicates that it has selective toxicity and it could be applied as a less toxic alternative to the current formulations.  相似文献   

4.
Ursolic acid (UA), which is a natural pentacyclic triterpenoid, has the potential to be developed as an anticancer drug, whereas its poor aqueous solubility and dissolution rate limit its clinical application. The aim of the present study was to develop UA nanocrystals to enhance its aqueous dispersibility, dissolution rate and anticancer activity. Following the investigation on the effects of stabiliser, the ratio of organic phase to aqueous solution and drug concentration, the UA nanocrystals without stabiliser were successfully prepared by anti-solvent precipitation approach. The nanocrystals maintained similar crystallinity with particle size, polydispersion index and zeta potential values of 188.0 ± 4.4 nm, 0.154 ± 0.022, and −25.0 ± 5.9 mV, respectively. Compared with the raw material, the UA nanocrystals showed good aqueous dispensability and a higher dissolution rate, and they could be completely dissolved in 0.5% SDS solution within 120 min. Moreover, the suspension of UA nanocrystals was physically stable after storage at 4°C for 7 weeks. By inducing G2/M phase cell cycle arrest, the UA nanocrystals significantly induced stronger cell growth inhibition activity against MCF-7 cells compared with free drug in vitro, although the uptake of free UA was approximately twice higher than that of the UA nanocrystals. The UA nanocrystals may be used as a potential delivery formulation for intravenous injection with enhanced dissolution velocity and anticancer activity.Key words: anticancer, dissolution, MCF-7, nanocrystals, ursolic acid  相似文献   

5.
Ellis RH  Hong TD 《Annals of botany》2006,97(5):785-791
Background and Aims The negative logarithmic relationship between orthodox seed longevity and moisture content in hermetic storage is subject to a low-moisture-content limit (mc), but is mc affected by temperature?• Methods Red clover (Trifolium pratense) and alfalfa (Medicago sativa) seeds were stored hermetically at 12 moisture contents (2–15 %) and five temperatures (–20, 30, 40, 50 and 65 °C) for up to 14·5 years, and loss in viability was estimated.• Key Results Viability did not change during 14·5 years hermetic storage at −20 °C with moisture contents from 2·2 to 14·9 % for red clover, or 2·0 to 12·0 % for alfalfa. Negative logarithmic relationships between longevity and moisture contents >mc were detected at 30–65 °C, with discontinuities at low moisture contents; mc varied between 4·0 and 5·4 % (red clover) or 4·2 and 5·5 % (alfalfa), depending upon storage temperature. Within the ranges investigated, a reduction in moisture content below mc at any one temperature had no effect on longevity. Estimates of mc were greater the cooler the temperature, the relationship (P < 0·01) being curvilinear. Above mc, the estimates of CH and CQ (i.e. the temperature term of the seed viability equation) did not differ (P > 0·10) between species, whereas those of KE and CW did (P < 0·001).• Conclusions The low-moisture-content limit to negative logarithmic relationships between seed longevity and moisture content in hermetic storage increased the cooler the storage temperature, by approx. 1·5 % over 35 °C (4·0–4·2 % at 65 °C to 5·4–5·5 % at 30–40 °C) in these species. Further reduction in moisture content was not damaging. The variation in mc implies greater sensitivity of longevity to temperature above, compared with below, mc. This was confirmed (P < 0·005).  相似文献   

6.
Coral Associated Bacteria (CAB) (N = 22) isolated from the mucus of the coral Acropora digitifera were screened for biosurfactants using classical screening methods; hemolysis test, lipase production, oil displacement, drop collapse test and emulsifying activity. Six CAB (U7, U9, U10, U13, U14, and U16) were found to produce biosurfactants and were identified by 16S ribosomal RNA gene sequencing as Providencia rettgeri, Psychrobacter sp., Bacillus flexus, Bacillus anthracis, Psychrobacter sp., and Bacillus pumilus respectively. Their cell surface hydrophobicity was determined by Microbial adhesion to hydrocarbon assay and the biosurfactants produced were extracted and characterized by Fourier Transform Infrared spectroscopy. Since the biosurfactants are known for their surface modifying capabilities, antibiofilm activity of positive isolates was evaluated against biofilm forming Pseudomonas aeruginosa ATCC10145. Stability of the active principle exhibiting antibiofilm activity was tested through various temperature treatments ranging from 60 to 100 °C and Proteinase K treatment. CAB isolates U7 and U9 exhibited stable antibiofilm activity even after exposure to higher temperatures which is promising for the development of novel antifouling agents for diverse industrial applications. Further, this is the first report on biosurfactant production by a coral symbiont.

Electronic supplementary material

The online version of this article (doi:10.1007/s12088-014-0474-8) contains supplementary material, which is available to authorized users.  相似文献   

7.
To investigate the larvicidal activities of novel anthraquinones (1a-1k) against Culex quinquefasciatus mosquito larvae. Novel anthraquinones (1a-1k) derivatives were synthesis via condensation method. The compounds were confirmed through FT-IR spectroscopy, 1H & 13C NMR spectrum, and mass spectral studies. The larvicidal activity of compound 1c was highly active LD50 20.92 µg/mL against Culex quinquefasciatus compared standard permethrin with LD50 25.49 µg/mL. Molecular docking studies were carried out for compound 1c against Odorant-binding protein of Culex quinquefasciatus. The compound 1c (−9.8 Kcal/mol) was a potent larvicide with more binding energy than control permethrin (−9.7 Kcal/mol). Therefore, compound (1c) may be more significant inhibitors of mosquito larvicidal.  相似文献   

8.

Background

In our investigations towards the isolation of potentially biologically active constituents from Orchidaceae, we carried out phytochemical and biological analyses of Vanda species. A preliminary biological screening revealed that Vanda coerulea (Griff. ex. Lindl) crude hydro-alcoholic stem extract displayed the best DPPH /OH radical scavenging activity and in vitro inhibition of type 2 prostaglandin (PGE-2) release from UVB (60 mJ/cm2) irradiated HaCaT keratinocytes.

Principal Findings

Bio-guided fractionation and phytochemical analysis led to the isolation of five stilbenoids: imbricatin (1) methoxycoelonin (2) gigantol (3) flavidin (4) and coelonin (5). Stilbenoids (1–3) were the most concentrated in crude hydro-alcoholic stem extract and were considered as Vanda coerulea stem biomarkers. Dihydro-phenanthropyran (1) and dihydro-phenanthrene (2) displayed the best DPPH/OH radical scavenging activities as well as HaCaT intracellular antioxidant properties (using DCFH-DA probe: IC50 8.8 µM and 9.4 µM, respectively) compared to bibenzyle (3) (IC50 20.6 µM). In turn, the latter showed a constant inhibition of PGE-2 production, stronger than stilbenoids (1) and (2) (IC50 12.2 µM and 19.3 µM, respectively). Western blot analysis revealed that stilbenoids (1–3) inhibited COX-2 expression at 23 µM. Interestingly, stilbenoids (1) and (2) but not (3) were able to inhibit human recombinant COX-2 activity.

Conclusions

Major antioxidant stilbenoids (1–3) from Vanda coerulea stems displayed an inhibition of UVB-induced COX-2 expression. Imbricatin (1) and methoxycoelonin (2) were also able to inhibit COX-2 activity in a concentration-dependent manner thereby reducing PGE-2 production from irradiated HaCaT cells. Our studies suggest that stilbenoids (1–3) could be potentially used for skin protection against the damage caused by UVB exposure.  相似文献   

9.
Piper longum L. (Piperaceae) commonly known as “long pepper” is a well known medicinal plant in ayurveda. Different parts of this plant, such as root, seed, fruit, whole plant etc. are used traditionally in various ailments. Here we have investigated the antidermatophytic activity of sequentially extracted petroleum ether, chloroform, methanol and water extracts from P. longum leaf against Trichophytonmentagrophytes, T. rubrum, T. tonsurans, Microsporum fulvum and M. gypseum. Better activity of chloroform and methanol extracts was observed. The chloroform extract was selected for further study and the MIC value was recorded as 5.0 mg ml−1 against the test organisms. In the chloroform extract, tannins and phenolic compounds were detected. Further activity-guided fractionation of chloroform extract by silica gel column chromatography yielded nine major fractions. Among these, fraction-1, 4, 5 and 7 showed higher antidermatophytic activity. Fraction-4 on further purification by repeated column chromatography yielded a potential antidermatophytic fraction showing MIC value of 0.625 mg ml−1 against T. mentagrophytes and T. rubrum as determined by broth microdilution method. The major compounds were identified as 1,2-benzenedicarboxylic acid, bis(2-ethylhexyl) ester (C24H38O4] (41.45 %), 2,2-dimethoxybutane (C6H14O2] (13.6 %) and β-myrcene (C10H16) (6.75 %) based on GC–MS data.  相似文献   

10.

Background

This study was subjected to investigate different pharmacological properties of ethanol extract of Solena amplexicaulis root.

Results

The extract contains flavonoid, alkaloid, saponin and steroid compounds. The extract exhibited excellent antioxidant activity in DPPH radical scavenging activity. The extract also showed potent activity in brine shrimp lethality bioassay. The LC50 value was found to 44.677 μg/ml. The extract showed better anti-bacterial activity against gram-negative bacteria. In antifungal assay, the maximum 79.31% of anti-mycotic activity was observed against Aspergillus ochraceus while minimum 44.2% against Rhizopus oryzae. MIC value ranged between 1500–3000 μg/ml. The extract was found moderately toxic with a 24-hr LD50 value of 81.47 mg/kg in Swiss albino mice. The degree of inhibition by the ethanolic extract of the root was found less than that of standard analgesic drug diclofenac sodium. The extract also showed moderate anti-inflammatory and antinociceptive activity and anti-diabetic property. Reducing power of the extract was comparable with standard ascorbic acid. Moderate in vitro thrombolytic activity, lipid peroxidation inhibition property, metal chelating ability and stress-protective activity was also observed.

Conclusion

Ethanol extract of Solena amplexicaulis root can be valuable for treatment of different diseases.  相似文献   

11.

Background

Structural and biochemical studies of mammalian membrane proteins remain hampered by inefficient production of pure protein. We explored codon optimization based on highly expressed Pichia pastoris genes to enhance co-translational folding and production of P-glycoprotein (Pgp), an ATP-dependent drug efflux pump involved in multidrug resistance of cancers.

Methodology/Principal Findings

Codon-optimized “Opti-Pgp” and wild-type Pgp, identical in primary protein sequence, were rigorously analyzed for differences in function or solution structure. Yeast expression levels and yield of purified protein from P. pastoris (∼130 mg per kg cells) were about three-fold higher for Opti-Pgp than for wild-type protein. Opti-Pgp conveyed full in vivo drug resistance against multiple anticancer and fungicidal drugs. ATP hydrolysis by purified Opti-Pgp was strongly stimulated ∼15-fold by verapamil and inhibited by cyclosporine A with binding constants of 4.2±2.2 µM and 1.1±0.26 µM, indistinguishable from wild-type Pgp. Maximum turnover number was 2.1±0.28 µmol/min/mg and was enhanced by 1.2-fold over wild-type Pgp, likely due to higher purity of Opti-Pgp preparations. Analysis of purified wild-type and Opti-Pgp by CD, DSC and limited proteolysis suggested similar secondary and ternary structure. Addition of lipid increased the thermal stability from Tm ∼40°C to 49°C, and the total unfolding enthalpy. The increase in folded state may account for the increase in drug-stimulated ATPase activity seen in presence of lipids.

Conclusion

The significantly higher yields of protein in the native folded state, higher purity and improved function establish the value of our gene optimization approach, and provide a basis to improve production of other membrane proteins.  相似文献   

12.
13.
Extracellular heat shock protein 72 (eHsp72) concentration increases during exercise-heat stress when conditions elicit physiological strain. Differences in severity of environmental and exercise stimuli have elicited varied response to stress. The present study aimed to quantify the extent of increased eHsp72 with increased exogenous heat stress, and determine related endogenous markers of strain in an exercise-heat model. Ten males cycled for 90 min at 50 % in three conditions (TEMP, 20 °C/63 % RH; HOT, 30.2 °C/51%RH; VHOT, 40.0 °C/37%RH). Plasma was analysed for eHsp72 pre, immediately post and 24-h post each trial utilising a commercially available ELISA. Increased eHsp72 concentration was observed post VHOT trial (+172.4 %) (p < 0.05), but not TEMP (−1.9 %) or HOT (+25.7 %) conditions. eHsp72 returned to baseline values within 24 h in all conditions. Changes were observed in rectal temperature (Trec), rate of Trec increase, area under the curve for Trec of 38.5 and 39.0 °C, duration Trec ≥ 38.5 and ≥39.0 °C, and change in muscle temperature, between VHOT, and TEMP and HOT, but not between TEMP and HOT. Each condition also elicited significantly increasing physiological strain, described by sweat rate, heart rate, physiological strain index, rating of perceived exertion and thermal sensation. Stepwise multiple regression reported rate of Trec increase and change in Trec to be predictors of increased eHsp72 concentration. Data suggests eHsp72 concentration increases once systemic temperature and sympathetic activity exceeds a minimum endogenous criteria elicited during VHOT conditions and is likely to be modulated by large, rapid changes in core temperature.  相似文献   

14.
Offord CA 《Annals of botany》2011,108(2):347-357

Background and Aims

Under predicted climate change scenarios, increased temperatures are likely to predispose trees to leaf and other tissue damage, resulting in plant death and contraction of already narrow distribution ranges in many relictual species. The effects of predicted upward temperatures may be further exacerbated by changes in rainfall patterns and damage caused by frosts on trees that have been insufficiently cold-hardened. The Araucariaceae is a relictual family and the seven species found in Australia have limited natural distributions characterized by low frost intensity and frequency, and warm summer temperatures. The temperature limits for these species were determined in order to help understand how such species will fare in a changing climate.

Methods

Experiments were conducted using samples from representative trees of the Araucariaceae species occurring in Australia, Agathis (A. atropurpurea, A. microstachya and A. robusta), Arauacaria (A. bidwilli, A. cunninghamii and A. heterophylla) and Wollemia nobilis. Samples were collected from plants grown in a common garden environment. Lower and higher temperature limits were determined by subjecting detached winter-hardened leaves to temperatures from 0 to –17 °C and summer-exposed leaves to 25 to 63 °C, then measuring the efficiency of photosystem II (Fv/Fm) and visually rating leaf damage. The exotherm, a sharp rise in temperature indicating the point of ice nucleation within the cells of the leaf, was measured on detached leaves of winter-hardened and summer temperature-exposed leaves.

Key Results

Lower temperature limits (indicated by FT50, the temperature at which PSII efficiency is 50 %, and LT50 the temperature at which 50 % visual leaf damage occurred) were approx. –5·5 to –7·5 °C for A. atropurpurea, A. microstachya and A. heterophylla, approx. –7 to –9 °C for A. robusta, A. bidwillii and A. cunninghamii, and –10·5 to –11 °C for W. nobilis. High temperature damage began at 47·5 °C for W. nobilis, and occurred in the range 48·5–52 °C for A. bidwillii and A. cunninghamii, and in the range 50·5–53·5 °C for A. robusta, A. microstachya and A. heterophylla. Winter-hardened leaves had ice nucleation temperatures of –5·5 °C or lower, with W. nobilis the lowest at –6·8 °C. All species had significantly higher ice nucleation temperatures in summer, with A. atropurpurea and A. heterophylla forming ice in the leaf at temperatures >3 °C higher in summer than in winter. Wollemia nobilis had lower FT50 and LT50 values than its ice nucleation temperature, indicating that the species has a degree of ice tolerance.

Conclusions

While lower temperature limits in the Australian Araucariaceae are generally unlikely to affect their survival in wild populations during normal winters, unseasonal frosts may have devastating effects on tree survival. Extreme high temperatures are not common in the areas of natural occurrence, but upward temperature shifts, in combination with localized radiant heating, may increase the heat experienced within a canopy by at least 10 °C and impact on tree survival, and may contribute to range contraction. Heat stress may explain why many landscape plantings of W. nobilis have failed in hotter areas of Australia.  相似文献   

15.
Background and Aims The genetic variation and divergence estimated by allozyme analysis were used to reveal the evolutionary history of Castanopsis carlesii in Taiwan. Two major questions were discussed concerning evolutionary issues: where are the diversity centres, and where are the most genetically divergent sites in Taiwan?• Methods Twenty-two populations of C. carlesii were sampled throughout Taiwan. Starch gel electrophoresis was used to assay allozyme variation. Genetic parameters and mean FST values of each population were analysed using the BIOSYS-2 program. Mean FST values of each population against the remaining populations, considered as genetic divergence, were estimated using the FSTAT program.• Key Results Average values of genetic parameters describing the within-population variation, the average number of alleles per locus (A = 2·5), the effective number of alleles per locus (Ae = 1·38), the allelic richness (Ar = 2·38), the percentage of polymorphic loci (P = 69 %), and the expected heterozygosity (He = 0·270) were estimated. High levels of genetic diversity were found for C. carlesii compared with other local plant species. Genetic differentiation between populations was generally low.• Conclusions From the data of expected heterozygosity, one major diversity centre was situated in central Taiwan corroborating previous reports for other plant species. According to the mean FST value of each population, the most divergent populations were situated in two places. One includes populations located in north central Taiwan between 24·80°N and 24·20°N. The other is located in south-eastern Taiwan between 22·40°N and 23·10°N. These two regions are approximately convergent with the most divergent locations determined for several other plant species using chloroplast DNA markers published previously. An important finding obtained from this study is that unordered markers like allozymes can be used to infer past population histories as well as chloroplast DNA markers do.  相似文献   

16.

Background

Based on the ethnomedicinal uses and the effective outcomes of natural products in various diseases, this study was designed to evaluate Isodon rugosus as possible remedy in oxidative stress, alzheimer’s and other neurodegenerative diseases. Acetylecholinestrase (AChE) and butyrylcholinesterase (BChE) inhibitory activities of crude methanolic extract (Ir.Cr), resultant fractions (n-hexane (Ir.Hex), chloroform (Ir.Cf), ethyl acetate (Ir.EtAc), aqueous (Ir.Aq)), flavonoids (Ir.Flv) and crude saponins (Ir.Sp) of I. rugosus were investigated using Ellman’s spectrophotometric method. Antioxidant potential of I. rugosus was determined using DPPH, H2O2 and ABTS free radicals scavenging assays. Total phenolic and flavonoids contents of plant extracts were determined and expressed in mg GAE/g dry weight and mg RTE/g of dry sample respectively.

Results

Among different fractions Ir.Flv and Ir.Cf exhibited highest inhibitory activity against AChE (87.44 ± 0.51, 83.73 ± 0.64%) and BChE (82.53 ± 0.71, 88.55 ± 0.77%) enzymes at 1 mg/ml with IC50 values of 45, 50 for AChE and 40, 70 μg/ml for BChE respectively. Activity of these fractions were comparable to galanthamine causing 96.00 ± 0.30 and 88.61 ± 0.43% inhibition of AChE and BChE at 1 mg/ml concentration with IC50 values of 20 and 47 μg/ml respectively. In antioxidant assays, Ir.Flv, Ir.Cf, and Ir.EtAc demonstrated highest radicals scavenging activities in DPPH and H2O2 assays which were comparable to ascorbic acid. Ir.Flv was found most potent with IC50 of 19 and 24 μg/ml against DPPH and H2O2 radicals respectively. Whereas antioxidant activates of plant samples against ABTS free radicals was moderate. Ir.Cf, Ir.EtAc and Ir.Cr showed high phenolic and flavonoid contents and concentrations of these compounds in different fractions correlated well to their antioxidant and anticholinestrase activities.

Conclusion

It may be inferred from the current investigations that the Ir.Sp, Ir.Flv and various fractions of I. rugosus are good sources of anticholinesterase and antioxidant compounds. Different fractions can be subjected to activity guided isolation of bioactive compounds effective in neurological disorders.  相似文献   

17.
Breviscapine is used in the treatment of ischemic cerebrovascular diseases, but it has a low bioavailability in the brain due to its poor physicochemical properties and the activity of P-glycoprotein efflux pumps located at the blood–brain barrier. In the present study, breviscapine-loaded solid lipid nanoparticles (SLN) coated with polyethylene glycol (PEG) derivatives were formulated and evaluated for their ability to enhance brain bioavailability. The SLNs were either coated with polyethylene glycol (40) (PEG-40) stearate alone (Bre-GBSLN-PS) or a mixture of PEG-40 stearate and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-PEG2000 (DSPE-PEG2000) (Bre-GBSLN-PS-DSPE) and were characterized both in vitro and in vivo. The mean particle size, polydispersity index, and entrapment efficiency for Bre-GBSLN-PS and Bre-GBSLN-PS-DSPE were 21.60 ± 0.10 and 22.60 ± 0.70 nm, 0.27 ± 0.01 and 0.26 ± 0.04, and 46.89 ± 0.73% and 47.62 ± 1.86%, respectively. The brain pharmacokinetic parameters revealed that the brain bioavailability of breviscapine from the Bre-GBSLN-PS and Bre-GBSLN-PS-DSPE was significantly enhanced (p < 0.01) with the area under concentration–time curve (AUC) of 1.59 ± 0.39 and 1.42 ± 0.58 μg h/mL of breviscapine, respectively, in comparison to 0.11 ± 0.02 μg h/mL from the commercial breviscapine injection. The ratios of the brain AUC for scutellarin in comparison with the plasma scutellarin AUC for commercial breviscapine injection, Bre-GBSLN-PS, and Bre-GBSLN-PS-DSPE were 0.66%, 2.82%, and 4.51%, respectively. These results showed that though both SLN formulations increased brain uptake of breviscapine, Bre-GBSLN-PS-DSPE which was coated with a binary combination of PEG-40 stearate and DSPE-PEG2000 had a better brain bioavailability than Bre-GBSLN-PS. Thus, the coating of SLNs with the appropriate PEG derivative combination could improve brain bioavailability of breviscapine and can be a promising tool for brain drug delivery.KEY WORDS: breviscapine, microdialysis, mixed PEGylation, P-glycoprotein (P-gp), solid lipid nanoparticles  相似文献   

18.
Insulin-producing cells express limited activities of anti-oxidative enzymes. Therefore, reactive oxygen species (ROS) produced in these cells play a crucial role in cytotoxic effects. Furthermore, diabetes mellitus (DM) development is closely linked to higher ROS levels in insulin-producing cells. Hita Tenryosui Water® (Hita T. W., Hita, Japan) and Nordenau water (Nord. W., Nordenau, Germany), referred to as natural reduced waters (NRWs), scavenge ROS in cultured cells, and therefore, might be a possibility as an alternative to conventional pharmacological agents against DM. Therefore, this study aimed to investigate the role of NRWs in alloxan (ALX)-induced β-cell apoptosis as well as in ALX-induced diabetic mice. NRWs equally suppressed DNA fragmentation levels. Hita T. W. and Nord. W. ameliorated ALX-induced sub-G1 phase production from approximately 40% of control levels to 8.5 and 11.8%, respectively. NRWs restored serum insulin levels (p < 0.01) and reduced blood glucose levels (p < 0.01) in ALX-induced mice. Hita T. W. restored tissue superoxide dismutase (SOD) (p < 0.05) activity but not tissue catalase activity. Hita T. W. did not elevate SOD or catalase activity in HIT-T15 cells. Nord. W. restored SOD (p < 0.05) and catalase (p < 0.05) activity in both cultured cells and pancreatic tissue to normal levels. Even though variable efficacies were observed between Hita T. W. and Nord. W., both waters suppressed ALX-induced DM development in CD-1 male mice by administering NRWs for 8 weeks. Our results suggest that Hita T. W. and Nord. W. protect against ALX-induced β-cell apoptosis, and prevent the development of ALX-induced DM in experimental animals by regulating ALX-derived ROS generation and elevating anti-oxidative enzymes. Therefore, the two NRWs tested here are promising candidates for the prevention of DM development.  相似文献   

19.
A series of [1]benzothieno[2,3-c]pyridines was synthesised. Most compounds were chosen by NCI-USA to evaluate their anticancer activity. Compounds 5a–c showed prominent growth inhibition against most cell lines. 5c was selected at five dose concentration levels. It exhibited potent broad-spectrum anticancer activity with a GI50 of 4 nM–37 µM. Cytotoxicity of 5a–c was further evaluated against prostate, renal, and breast cancer cell lines. 5c showed double and quadruple the activity of staurosporine and abiraterone, respectively, against the PC-3 cell line with IC50 2.08 µM. The possible mechanism of anti-prostate cancer was explored via measuring the CYP17 enzyme activity in mice prostate cancer models compared to abiraterone. The results revealed that 5c suppressed the CYP17 enzyme to 15.80 nM. Moreover, it was found to be equipotent to abiraterone in testosterone production. Cell cycle analysis and apoptosis were performed. Additionally, the ADME profile of compound 5c demonstrated both good oral bioavailability and metabolic stability.  相似文献   

20.
Extracellular glucoamylase of Colletotrichum sp. KCP1 produced through solid state fermentation was purified by two steps purification process comprising ammonium sulphate precipitation followed by gel permeation chromatography (GPC). The Recovery of glucoamylase after GPC was 50.40 % with 19.3-fold increase in specific activity. The molecular weight of enzyme was found to be 162.18 kDa by native-PAGE and was dimeric protein of two sub-units with molecular weight of 94.62 and 67.60 kDa as determined by SDS-PAGE. Activation energy for starch hydrolysis was 26.45 kJ mol−1 while temperature quotient (Q10) was found to be 1.9. The enzyme was found to be stable over wide pH range and thermally stable at 40–50 °C up to 120 min while exhibited maximum activity at 50 °C with pH 5.0. The pKa1 and pKa2 of ionisable groups of active site controlling Vmax were 3.5 and 6.8, respectively. Vmax, Km and Kcat for starch hydrolysis were found to be 58.82 U ml−1, 1.17 mg (starch) ml−1 and 449 s−1, respectively. Activation energy for irreversible inactivation (Ea(d)) of glucoamylase was 74.85 kJ mol−1. Thermodynamic parameters of irreversible inactivation of glucoamylase and starch hydrolysis were also determined.  相似文献   

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