Intravenous rutin in rat exacerbates isoprenaline-induced cardiotoxicity likely due to intracellular oxidative stress

Objectives: Rutin, quercetin-3-O-rutinoside, a natural flavonol glycoside, has shown various in vitro benefits with potential use treating human diseases, especially cardiovascular system disorders. Antioxidant properties are assumed to underlie the majority of these benefits. Yet rutin pro-oxidant properties have been reported as well. Our research group has recently shown aggravating effects on isoprenaline (ISO)-induced cardiotoxicity in Wistar:Han rats after 24?hours.

Methods: This study was designed to examine in more detail the reasons for the negative effects of rutin (11.5 and 46?mg/kg, i.v.) after administration of ISO (100?mg/kg, s.c.) in rats within 2?hours of continuous experiment and in the H9c2 cardiomyoblast-derived cell line.

Results: Like our previous findings, rutin did not (11.5 or 46?mg/kg, i.v.) reduce the ISO-induced mortality within 2?hours although the lower dose significantly reduced cardiac troponin T (cTnT) and partly improved the histological findings. In contrast, the higher dose increased the mortality in comparison with solvent (1.26% w/v sodium bicarbonate). This was not caused by any specific haemodynamic disturbances. It appears to be associated with oxidative stress as rutin enhanced intracellular reactive oxygen species formation in vitro and had the tendency to increase it in vivo.

Conclusions: Rutin, likely due to its pro-oxidative effects, can exacerbate catecholamine cardiotoxicity depending on the dose used.     

Preparation and anti-inflammatory activity of triptolide ethosomes in an erythema model

Context: The aim of this work was to evaluate the suitability of ethosomes as carriers for the topical application of triptolide in a rat model of erythema.

Objective: We determined the optimal conditions for preparing ethosomes, and we measured their vesicle size by a laser particle-size analyzer and the efficiency of entrapment of triptolide by ultracentrifugation.

Methods: The in vitro percutaneous permeation of triptolide-loaded ethosomes was investigated by measuring diffusion across a sample of rat skin. To explore the transdermal delivery in vivo, we used a model in which erythema was induced in rats by methyl nicotinate and determined the change in erythema index caused by the anti-inflammatory activity of triptolide by a reflection spectrophotometer.

Results: The optimal conditions for preparing triptolide ethosomes consisted of ultrasonication of 45% (v/v) ethanol and 2% (w/v) DPPC for 5 minutes, which produced an average vesicle size of 51.4?nm and an entrapment efficiency of 98%. This ethosomal formulation of triptolide caused the greatest in vitro 24-hour accumulation of triptolide (83.7%) with no permeation time delay, and it reduced erythema in vivo more rapidly and more completely than other formulations.

Conclusions: Ethosomes might be a promising carrier that would enable the beneficial properties of triptolide to be safely delivered in a topical formulation.     

The synthesis of α-amylase by rough and in vitro reconstituted rough endoplasmic reticulum derived from rat parotid gland

Summary The isolation of rough and smooth endoplasmic reticulum from rat parotid salivary gland is described. The rough membrane was stripped of its bound ribosomes using the KCl-puromycin method. Rough endoplasmic reticulum was reconstituted from stripped-rough membrane and polyribosomes. The reconstituted rough membrane resembled the native rough membrane in the following aspects: RNA/protein ratio, buoyant density in a continuous sucrose gradient and amino acid incorporation capacity. The in vitro synthesis of -amylase by both rough and in vitro reconstituted rough membrane was demonstrated using SDS polyacrylamide gel electrophoresis. The reconstituted rough membrane could be restripped by KCl-puromycin. The in vitro synthesized -amylase remained associated with the rough or the in vitro reconstituted rough membrane, even after these membranes were stripped of their bound ribosomes.Abbreviations Fp Free polyribosomes - Bp Membrane-bound polyribosomes released by DOC - RM Rough membrane - SM Smooth membrane - RMst Rough membrane stripped - RMrec In vitro reconstituted rough membrane - DOC Sodium deoxycholate     

Chloro and bromo-pyrazole curcumin Knoevenagel condensates augmented anticancer activity against human cervical cancer cells: design,synthesis, in silico docking and in vitro cytotoxicity analysis

Abstract

With an endeavor to develop novel curcumin analogs as potential anti-cancer agents, we designed and synthesized a series of Knoevenagel condensates by clubbing pyrazole carbaldehydes at the active methylene carbon atom of the curcumin backbone. Molecular docking studies were carried out to target the proposed derivatives on human kinase β (IKKβ), a potential anti-cancer target. The chloro derivative displayed five hydrogen bond interactions with a docking score of ?11.874?kcal/mol higher than curcumin (docking score =??7.434?kcal/mol). This was supported by the fact that the propellant shaped derivatives fitted aptly into the binding pocket. Molecular simulations studies were also conducted on the lead molecule and the results figured out that the stable complexes were developed as the minimal deviations per residue of protein within the range of 0.11–0.92 Å. The screened compounds were synthesized, characterized and evaluated in vitro for cytotoxicity against cervical cancer cell line, HeLa using standard cell proliferation assay. Chloro derivative and bromo analog demonstrated IC₅₀ (half maximal inhibitory concentration) value of 14.2 and 18.6 µg/ml, respectively, significantly lower than 42.4 µg/ml of curcumin and higher than 0.008 µg/ml of paclitaxel. Induction of apoptosis was evaluated in the terms of cleavage of caspase-3 enzyme and they also exhibited 69.6 and 65.4% of apoptosis significantly higher than 19.9% induced by curcumin. In conclusion, chloro and bromo derivatives must be evaluated under a set of stringent in vitro and in vivo parameters for translating in to a clinically viable product.

Communicated by Ramaswamy H. Sarma     

Arabitol accumulation in Geotrichum candidum

Culture conditions which lead to the intracellular accumulation of arabitol and mannitol in Geotrichum candidum were investigated. The accumulation of arabitol was dependent on the concentrations of metabolizable hexoses, the non-metabolizable disaccharide sucrose, NaCl and KCl in the growth medium. In media containing 2% (w/v) glucose, fructose or l-sorbose cultures contained only mannitol after 48 h or 72 h growth. In media containing 10% (w/v) to 30% (w/v) glucose, or 25% (w/v) fructose or l-sorbose there was an increase in the total concentration of intracellular polyol due to the accumulation of arabitol. This pentitol was also found to accumulate intracellularly when the organism was grown in medium containing 34% (w/v) sucrose, 0.7 M NaCl or 0.7 M KCl in addition to 2% (w/v) glucose. Under the conditions tested no change in the accumulation of mannitol or ethanol-soluble carbohydrate, believed to be primarily composed of trehalose, was evident.Intracellular polyol was released during incubation of arthrospores obtained from media containing 25% or 10% glucose, in distilled water at 25° C, but no polyol was released under these conditions from arthrospores obtained from growth in 2% glucose medium.     

Improved Viability of Microencapsulated Probiotics in a Freeze-Dried Banana Powder During Storage and Under Simulated Gastrointestinal Tract

Freeze-dried banana powder represents an ideal source of nutrients and has not yet been used for probiotic incorporation. In this study, microencapsulation by freeze drying of probiotics Lactobacillus acidophilus and Lactobacillus casei was made using whey protein isolate (WPI), fructooligosaccharides (FOS), and their combination (WPI + FOS) at ratio (1:1). Higher encapsulation yield was found for (WPI + FOS) microspheres (98%). Further, microcapsules of (WPI + FOS) were used to produce a freeze-dried banana powder which was analyzed for bacterial viability under simulated gastrointestinal fluid (SGIF), stability during storage at 4 °C and 25 °C, and chemical and sensory properties. Results revealed that (WPI + FOS) microcapsules significantly increased bacteria stability in the product over 30 days of storage at 4 °C averaging (≥ 8.57 log CFU/g) for L. acidophilus and (≥ 7.61 log CFU/g) for L. Casei as compared to free cells. Bacteria encapsulated in microspheres (WPI + FOS) were not significantly affected by the SGIF, remaining stable up to 7.05 ± 0.1 log CFU/g for L.acidophilus and 5.48 ± 0.1 log CFU/g for L.casei after 90 min of incubation at pH 2 compared to free cells which showed minimal survival. Overall, encapsulated probiotics enriched freeze-dried banana powders received good sensory scores; they can therefore serve as safe probiotics food carriers.

     

Titanium oxide nanoparticles fabrication,hemoglobin interaction,white blood cells cytotoxicity,and antibacterial studies

This study is focused on the fabrication and characterization of titanium oxide (TiO₂) NPs. Afterwards; the interaction of TiO₂ NPs with human hemoglobin (Hb) was investigated by FTIR spectroscopy, fluorescence spectroscopy, and molecular docking studies. Also, the cytotoxic effect of fabricated TiO₂ NPs against human white blood cells (WBCs) was considered by MTT assay. The antibacterial effect of synthesized NPs was examined on Pseudomonas aeruginosa (ATCC 27853); Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923). TEM and DLS investigations showed that the synthesized TiO₂ NPs have a narrow nano-sized distribution. XRD pattern of the fabricated NPs exhibited that the TiO₂ NPs contain anatase phase. Similarity in amide I and II signal intensities showed that secondary structure of the adsorbed Hb is preserved. The intrinsic fluorescence study revealed that the fluorescence quenching of Hb was done by complex formation between Hb and TiO₂ NPs trough the hydrogen bond and van der Waals interactions. Synchronous fluorescence spectroscopy determined that interaction of TiO₂ NPs with Hb did not unfold the Hb structure in the vicinity of the Tyr and Trp residues. Molecular docking study depicted that Glu-95, Thr-134 and Tyr-140 are involved in the formation of hydrophilic bonds. MTT data and antibacterial assays indicated that TiO₂ NPs endow distinguished antibacterial activities against Gram-negative and Gram positive strains at safe concentrations. This study may reveal that fabricated TiO₂ NP can be used as a safe and potent antibacterial agent.

Communicated by Ramaswamy H. Sarma     

Relative importance of maltose and sucrose supplied during a 2-step potato microtuberization process

A 2-stage in vitro tuberization process comprising first micropropagation via nodal explants and then tuber induction in the resultant in vitro plantlets was studied using 2 cultivars of potato, Iwa and Daeji. In particular, the effects on both plantlet growth and subsequent in vitro tuberization of Murashige and Skoog (1962) basal medium containing either sucrose or maltose, each at 3 % (w/v), used for micropropagation were investigated. Sucrose and maltose were found to be equally effective in supporting development of vigorous plantlets from the nodal explants of both potato cultivars. Upon transfer to a medium with an optimised level of sucrose (i.e. 8 %, w/v) for in vitro tuberization, only the plantlets previously grown in the sucrose-containing medium were capable of forming more microtubers of the larger size category (greater than 0.5 g). The relative importance of sucrose supply at the mircropropagation stage was further confirmed when the resultant plantlets grown in the 3 % sucrose-containing medium were transferred to an in vitro tuberization medium containing either sucrose or maltose, each at 8 % (w/v). In this experiment, maltose and sucrose had indistingushable effects on in vitro tuberization.     

Gaining insights into cancer biology through exploration of the cancer secretome using proteomic and bioinformatic tools

Introduction: Tumor-associated proteins released by cancer cells and by tumor stroma cells, referred as ‘cancer secretome’, represent a valuable resource for discovery of potential cancer biomarkers. The last decade was marked by a great increase in number of studies focused on various aspects of cancer secretome including, composition and identification of components externalized by malignant cells and by the components of tumor microenvironment.

Areas covered: Here, we provide an overview of achievements in the proteomic analysis of the cancer secretome, elicited through the tumor-associated interstitial fluid recovered from malignant tissues ex vivo or the protein component of conditioned media obtained from cultured cancer cells in vitro. We summarize various bioinformatic tools and approaches and critically appraise their outcomes, focusing on problems and challenges that arise when applied for the analysis of cancer secretomic databases.

Expert commentary: Recent achievements in the omics- analysis of structural and metabolic aspects of altered cancer secretome contribute greatly to the various hallmarks of cancer including the identification of clinically significant biomarkers and potential targets for therapeutic intervention.     

In vitro propagation of Notocactus magnificus

Most commercially grown cacti can be easily propagated by seed and/or cuttings. A group of rare and endangered species does not fit into this category and is therefore a good candidate for in vitro propagation productions as a tool to overcome habitat and plant-destruction. The number of rare and endangered species of Cacti goes into about 100. Many show a low production and germination of seeds and plantlets are prone to damping-off, making the in vitro propagation a feasible alternative for the multiplication and conservation of their germplasm. The aim of the present investigation is to establish a protocol for the in vitro culture and plant regeneration of Notocactus magnificus, the blue cactus, a highly ornamental species, native to Brazil. The surface sterilization of the explants was achieved with immersion for 10 min in sodium hypochlorite solution for either seeds (0.25% v/v) or ribs segments (1% v/v). Callus formation was observed when explants were cultured on MS medium supplemented with sucrose at 2% (w/v), 2,4-dichlorophenoxyacetic acid 0.5 μM, benzylaminopurine 4.4 μM, thiamine HCl 0.4 mg l⁻¹ and i-inositol 100 mg l⁻¹. The regeneration of shoots was carried out on MS medium supplemented with either different concentrations of benzylaminopurine and 1-naphthaleneacetic acid, or kinetin and indole-3-acetic acid. The highest number of shoots occurred when MS medium was supplemented with benzylaminopurine 22.2 μM, sucrose 3% (w/v) and agar 0,6% (w/v). In vitro spontaneous rooting of shoots was observed after eight months under culture on MS medium. Only in vitro rooted shoots developed into normal plants under glasshouse culture conditions. This in vitro protocol should be useful for the conservation as well as mass propagation of Notocactus magnificus.     

Rapid clonal propagation of Saccharum officinarum L. Vars. CO-6907 and CO-86249 and to assess the genetic uniformity through molecular markers

Abstract

An efficient protocol was developed for in vitro clonal propagation of Saccharum officinarum Vars. CO-6907 and CO-86249 through axillary meristem culture. Maximum meristem elongation was achieved on Murashige and Skoog's (MS) medium supplemented with 0.5 mg/L 6-benzyladenine (BA) and 0.5 mg/L kinetin (Kn) within 15 days of culture. Multiple shoots were induced from meristems on MS basal medium supplemented with 1.0 mg/L BA, 0.5 mg/L Kn, 0.25 mg/L 1-napthaleneacetic acid (NAA) and 3% (w/v) sucrose. Addition of 0.1–0.25 mg/L gibberellic acid into the multiplication medium found the better shoot elongation. Repeated subculture on multiplication medium induces higher rate of shoot multiplication. The root induction from excised microshoots was achieved on half-strength MS medium supplemented with 1.0–2.0 mg/L NAA or indole-3-butyric acid and 6% (w/v) sucrose. While either decreasing or increasing of sucrose concentration in the rooting medium, the percentage of rooting was reduced. Maximum percentage of rooting was achieved on medium having 2.0 mg/L NAA with 6% (w/v) sucrose. About 80% of micropropagated plantlets were hardened in the greenhouse and successfully established in the soil. Random Amplified Polymorphic DNA marker was used to detect the variability among the micropropagated plants developed through in vitro. The results showed that there was no polymorphism among the micropropagated plants. This study will help for propagation of quality planting material of high-yielding variety of sugarcane for commercialization.     

Gender-dependent differences of mitochondrial function and oxidative stress in rat skeletal muscle at rest and after exercise training

Objective: This study investigated gender-dependent differences of mitochondrial function and sensitivity to in vitro ROS exposure in rat skeletal muscle at rest and after exercise training.

Methods: Wistar rats underwent running training for 6 weeks. In vitro measurements of hydroxyl radical production, oxygen consumption (under basal and maximal respiration conditions) and ATP production were made on permeabilized fibers. Mitochondrial function was examined after exposure and non-exposure to an in vitro generator system of reactive oxygen species (ROS). Antioxidant enzyme activities and malondialdehyde (MDA) content were also determined.

Results: Compared with sedentary males, females showed a greater resistance of mitochondrial function (oxygen consumption and ATP production) to ROS exposure, and lower MDA content and antioxidant enzyme activities. The training protocol had more beneficial effects in males than females with regard to ROS production and oxidative stress. In contrast to male rats, the susceptibility of mitochondrial function to ROS exposure in trained females was unchanged.

Discussion: Exercise training improves mitochondrial function oxidative capacities in both male and female rats, but is more pronounced in males as a result of different mechanisms. The resistance of mitochondrial function to in vitro oxidative stress exposure and the antioxidant responses are gender- and training-dependent, and may be related to the protective effects of estrogen.     

PTD modified paclitaxel anti-resistant liposomes for treatment of drug-resistant non-small cell lung cancer

Context: Non-small cell lung carcinoma (NSCLC) is a type of epithelial lung cancer that accounts for approximately 80–85% of lung carcinoma cases. Chemotherapy for the NSCLC is unsatisfactory due to multidrug resistance, nonselectively distributions and the accompanying side effects.

Objective: The objective of this study was to develop a kind of PTD modified paclitaxel anti-resistant liposomes to overcome these chemotherapy limitations.

Method: The studies were performed on LLT cells and resistant LLT cells in vitro and on NSCLC xenograft mice in vivo, respectively.

Results and discussion: In vitro results showed that the liposomes with suitable physicochemical characteristics could significantly increase intracellular uptake in both LLT cells and resistant LLT cells, evidently inhibit the growth of cancer cells, and clearly induce the apoptosis of resistant LLT cells. Studies on resistant LLT cells xenograft mice demonstrated that the liposomes magnificently enhanced the anticancer efficacy in vivo. Involved action mechanisms were down-regulation of adenosine triphosphate binding cassette transporters on resistant LLT cells, and activation of the apoptotic enzymes (caspase 8/9/3).

Conclusion: The PTD modified paclitaxel anti-resistant liposomes may provide a promising strategy for treatment of the drug-resistant non-small cell lung cancer.     

Liposomal Anticancer Drugs as Agents to be used in Combination with other Anticancer Agents: Studies on a Liposomal Formulation with two Encapsulated Drugs

Abstract

When considering the use of combination therapies with liposomal anticancer agents several approaches can be defined. One approach could rely on administration of one liposomal formulation with more than one entrapped cytotoxic drug. This study focuses on an assessment of a liposomal formulation containing vincristine and mitoxantrone. Distearoyl phosphatidylcholine (DSPC)/Cholesterol (Choi) (55:45 molar ratio) liposomes were loaded with vincristine using transmembrane pH gradients. These systems were subsequently incubated with mitoxantrone to effect uptake of the second drug. Retention of both drugs was determined in vitro and in vivo. In vitro drug release indicated >95% retention of mitoxantrone and approximately 75% retention of vincristine when liposomes were prepared with an initial interior pH of 2.0. In vivo results however, demonstrated that greater than 80% of the encapsulated vincristine was released within 1 hour following i.v. administration. The instability of a liposomal formulation containing two anticancer drugs following i.v. administration may be a consequence of a combination of factors including drug-loading induced collapse of the transmembrane pH gradient, loss due to osmotic effects and an associated insertion of serum proteins into the bilayer, as well as the presence of a large biological “sink” which can alter the transbilayer drug gradient in favor of drug release.     

Preparation and characterization of novel albumin-sericin nanoparticles as siRNA delivery vehicle for laryngeal cancer treatment

Abstract

Small interfering RNA (siRNA)-based gene silencing strategy has high potential on suppressing specific molecular targets, involved in cancer progression. However, the lack of an effective nanocarrier system that safely delivers siRNA to its target still limits the clinical applications of siRNA. This study aimed to develop albumin-sericin nanoparticles (Alb-Ser NPs) as a novel siRNA delivery system for laryngeal cancer treatment. Nanoparticle formulations composed of albumin and sericin at different ratios (1:1, 2:1, 1:2 w/w) were synthesized by desolvation method. The nanoparticles were modified with poly-L-lysine (PLL) for siRNA binding and decorated with hyaluronic acid (HA) to target laryngeal cancer cell line, Hep-2. HA/PLL/Alb-Ser NPs were individually loaded with siRNAs for casein kinase 2 (CK2), Absent, Small, or Homeotic-Like (ASH2L), and Cyclin D1 genes, which are overexpressed in Hep-2 cells. Downregulation of genes was confirmed by real-time PCR (RT-PCR). Size, morphological, and thermogravimetric characterizations revealed that Alb-Ser NPs having 2:1 (w/w) ratio are the most optimized formulation. Between 36.8 and 61.3% of siRNA entrapment efficiencies were achieved. HA/PLL-siRNA/Alb-Ser (2:1) NPs-mediated gene silencing resulted in a significant inhibition of cell growth and induction of apoptosis in cells. Our findings showed that HA/PLL/Alb-Ser (2:1) NPs were promising as a siRNA carrier.     

Biochemical alterations induced by nickel oxide nanoparticles in female Wistar albino rats after acute oral exposure

Context: Nickel oxide (NiO) nanoparticles (NPs) with appropriate surface chemistry have been widely used for their potential new applications in biomedical industry. Increased usage of these NPs enhances the chance of exposure of personnel involved in the work place.

Objective: This study was designed to assess the ability of NiO NPs to cause biochemical alterations post-acute oral exposure in female Wistar rats.

Materials and methods: Rats were administered with 125, 250, and 500?mg/kg doses of NiO NPs for haematological, biochemical, and histopathological studies. Biodistribution patterns of NiO NPs in female Wistar rats were also monitored.

Results: NiO NPs caused significant (p?Conclusions: This study revealed that exposure to nanosized NiO particles at acute doses may cause adverse changes in animal biochemical profiles. Further, the in vivo studies on toxicity evaluation help in biomonitoring of the potential contaminants.     

Factorial design based curcumin ethosomal nanocarriers for the skin cancer delivery: in vitro evaluation

Abstract

Melanoma is the most deadly and life-threatening form of skin cancer with progressively higher rates of incidence worldwide. The objective of the present investigation is to develop and to statistically optimize and characterize curcumin (CUR) loaded ethosomes for treatment of melanoma. A two factor, three level (3²) factorial design approach was employed for the optimization of ethosomes. The prepared ethosomes were evaluated for size, zeta potential, entrapment efficiency, in vitro skin permeation and deposition ability. The optimized ethosomal formulation was evaluated for in vitro cytotoxicity and cellular uptake studies using A375 human melanoma cells. The optimized formulation has imperfect round shaped unilamellar structures with a mean vesicle size of 247?±?5.25?nm and an entrapment efficiency of 92.24?±?0.20%. The in vitro skin permeation studies proved the superiority of ethosomes over the traditional liposomes in terms of the amount of drug permeated and deposited in skin layers. Fluorescence microscopy showed the enhanced penetration of ethosomes into the deeper layers of the skin. In vitro cytotoxicity and cellular uptake studies revealed that curcumin ethosomes have significantly improved cytotoxicity and cellular uptake in A375 human melanoma cell lines. The colony formation assay results showed that curcumin ethosomes have a superior antiproliferative effect as they effectively inhibit the clonogenic ability of A375 cells. The flow cytometry results indicate that curcumin ethosomes induce cell death in A375 cells by apoptosis mechanism. The present study provides a strong rationale and motivation for further investigation of newly developed curcumin ethosomes as a potential therapeutic strategy for melanoma treatment.     

Enhanced oral bioavailability and anticancer activity of novel curcumin loaded mixed micelles in human lung cancer cells

BackgroundCurcumin has a wide range of pharmacological activities including antioxidant, anti-inflammatory, antidiabetic, antibacterial, wound healing, antiatherosclerotic, hepatoprotective and anti-carcinogenic. However, its clinical applications are limited owing to its poor aqueous solubility, multidrug pump P-gp efflux, extensive in vivo metabolism and rapid elimination due to glucuronidation/sulfation.PurposeThe objective of the current work was to prepare novel curcumin loaded mixed micelles (CUR-MM) of Pluronic F-127 (PF127) and Gelucire^® 44/14 (GL44) in order to enhance its oral bioavailability and cytotoxicity in human lung cancer cell line A549.Study design3² Factorial design was used to assess the effect of formulation variables for optimization of mixed micelle batch.MethodsCUR-MM was prepared by a solvent evaporation method. The optimized CUR-MM was evaluated for size, entrapment efficiency (EE), in vitro curcumin release, cytotoxicity and oral bioavailability in rats.ResultsThe average size of CUR-MM was found to be around 188 ± 3 nm with an EE of about 76.45 ± 1.18% w/w. In vitro dissolution profile of CUR-MM revealed controlled release of curcumin. Additionally, CUR-MM showed significant improvement in cytotoxic activity (3-folds) and oral bioavailability (around 55-folds) of curcumin as compared to curcumin alone. Such significant improvement in cytotoxic activity and oral bioavailability of curcumin when formulated into mixed micelles could be attributed to solubilization of hydrophobic curcumin into micelle core along with P-gp inhibition effect of both, PF127 and GL44.ConclusionThus the present work propose the formulation of mixed micelles of PF127 and GL44 which can act as promising carrier systems for hydrophobic drugs such as curcumin with significant improvement in their oral bioavailability.     

Trypanosoma brucei gambiense: HMI-9 medium containing methylcellulose and human serum supports the continuous axenic in vitro propagation of the bloodstream form

Trypanosoma brucei (T.b.) gambiense causes the chronic form of human African trypanosomiasis or sleeping sickness. One of the major problems with studying T.b. gambiense is the difficulty to isolate it from its original host and the difficult adaptation to in vivo and in vitro mass propagation. The objective of this study was to evaluate if an established method for axenic culture of pleomorphic bloodstream form T.b. brucei strains, based on methylcellulose containing HMI-9 medium, also facilitated the continuous in vitro propagation of other bloodstream form Trypanozoon strains, in particular of T.b. gambiense. Bloodstream form trypanosomes from one T.b. brucei, two T.b. rhodesiense, one T. evansi and seven T.b. gambiense strains were isolated from mouse blood and each was concurrently cultivated in liquid and methylcellulose-containing HMI-9 based medium, either with or without additional human serum supplementation, for over 10 consecutive sub passages. Although HMI-9 based medium supplemented with 1.1% (w/v) methylcellulose supported the continuous cultivation of all non-gambiense strains better than liquid media could, the in vitro cultivation of all gambiense strains was only achieved in HMI-9 based medium containing 1.1% (w/v) methylcellulose, 15% (v/v) fetal calf serum and 5% (v/v) heat-inactivated human serum.     

Curcumin prevents maleate-induced nephrotoxicity: Relation to hemodynamic alterations,oxidative stress,mitochondrial oxygen consumption and activity of respiratory complex I

Abstract

The potential protective effect of the dietary antioxidant curcumin (120 mg/Kg/day for 6 days) against the renal injury induced by maleate was evaluated. Tubular proteinuria and oxidative stress were induced by a single injection of maleate (400 mg/kg) in rats. Maleate-induced renal injury included increase in renal vascular resistance and in the urinary excretion of total protein, glucose, sodium, neutrophil gelatinase-associated lipocalin (NGAL) and N-acetyl β-D-glucosaminidase (NAG), upregulation of kidney injury molecule (KIM)-1, decrease in renal blood flow and claudin-2 expression besides of necrosis and apoptosis of tubular cells on 24 h. Oxidative stress was determined by measuring the oxidation of lipids and proteins and diminution in renal Nrf2 levels. Studies were also conducted in renal epithelial LLC-PK1 cells and in mitochondria isolated from kidneys of all the experimental groups. Maleate induced cell damage and reactive oxygen species (ROS) production in LLC-PK1 cells in culture. In addition, maleate treatment reduced oxygen consumption in ADP-stimulated mitochondria and diminished respiratory control index when using malate/glutamate as substrate. The activities of both complex I and aconitase were also diminished. All the above-described alterations were prevented by curcumin. It is concluded that curcumin is able to attenuate in vivo maleate-induced nephropathy and in vitro cell damage. The in vivo protection was associated to the prevention of oxidative stress and preservation of mitochondrial oxygen consumption and activity of respiratory complex I, and the in vitro protection was associated to the prevention of ROS production.