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1.
J Fungi (Basel) ; 9(7)2023 Jul 18.
Article in English | MEDLINE | ID: mdl-37504746

ABSTRACT

Azoles are the main antifungal agents employed in clinical practice to treat invasive candidiasis. Nonetheless, their efficacy is limited by fungal resistance mechanisms, mainly the overexpression of efflux pumps. Consequently, candidiasis has a worrisome death rate of 75%. One potential strategy to overcome efflux-mediated resistance is to inhibit this process. Ailanthus altissima is a Chinese tree that produces several active substances, including altissimacoumarin D. Due to the low yield of its extraction and the need to search for new drugs to treat candidiasis, this study aimed to synthesize altissimacoumarin D and its analogues, as well as evaluating their ability to reverse the resistance phenotype of Candida albicans. Coumarin isofraxidin was prepared via total synthesis through a solvent-free Knoevenagel condensation as the key step. Isofraxidin and other commercially available coumarins were alkylated with prenyl or geranyl groups to yield the natural product altissimacoumarin D and seven analogues. The antifungal activity of the coumarins and their ability to reverse the fungal resistance phenotype were assessed using microbroth methodologies. Toxicity was evaluated using erythrocytes and an in silico prediction. All compounds improved the antifungal activity of fluconazole by inhibiting efflux pumps, and ACS47 and ACS50 were the most active. None of the coumarins were toxic to erythrocytes. In silico predictions indicate that ACS47 and ACS50 may be safe for human use. ACS47 and ACS50 are promising candidates when used as adjuvants in the antifungal therapy against C. albicans-resistant strains.

2.
Environ Monit Assess ; 195(6): 691, 2023 May 19.
Article in English | MEDLINE | ID: mdl-37204496

ABSTRACT

The metal contamination and the degradation of polyethylene terephthalate (PET) due to human activities have contributed to the worsening of environmental problems in aquatic systems. Therefore, the study aimed to evaluate PET microplastic adsorption levels when exposed to high amounts of Ni, Cu and Co. The PET microplastic was characterized by scanning electron microscopy, Brunner-Emmet-Teller, porosimetry system, Barrett-Joyner-Halenda and Fourier transform infrared spectroscopy with attenuated total reflectance for evaluation of surface morphology, surface area, porosity, pore size and functional groups, respectively. The results showed that the surface area, the presence of macro and mesopores, and the functional groups influence the adsorption of metals on the surface of PET microplastic. The adsorption isotherms confirmed the presence of mesoporosity and macroporosity on the PET microplastic surface. The Freundlich and Langmuir models were used to study the adsorption capacity. The kinetics of adsorptions were interpreted using pseudo-first order and pseudo-second order models. The results indicated that the Langmuir isotherm and the pseudo-second order adequately described the adsorption of metals by the PET microplastic. The removal rates by the PET microplastic varied from 8 to 34% for Ni, 5 to 40% for Cu and 7 to 27% for Co after a period of 5 days. Furthermore, the adsorption was predominantly chemical and extremely fast, indicating that the presence of microplastics in the environment can lead to a rapid metal accumulation which elevates the hazards potential of microplastic in living beings.


Subject(s)
Microplastics , Water Pollutants, Chemical , Humans , Plastics , Water Pollutants, Chemical/analysis , Environmental Monitoring , Metals , Spectroscopy, Fourier Transform Infrared , Kinetics , Adsorption , Hydrogen-Ion Concentration
4.
ACS Omega ; 7(49): 45197-45207, 2022 Dec 13.
Article in English | MEDLINE | ID: mdl-36530239

ABSTRACT

This research aimed to produce, on a multigram scale, a new class of non-toxic, halogen- and metal-free antifouling agents from the abundant lecithin byproducts of industrial soybean oil extraction. Three glycerophospholipid analogues were prepared by a facile methanolysis of crude soybean lecithins and a subsequent solvent-free O-alkylation: lysoglycerophosphocholines (LGPCs) and its ether derivatives O-alkyl lysoglycerophosphocholines (ALPCs). As efficient antiproliferative agents, LGPCs and ALPCs are an eco-friendly alternative to current commercial antifoulants which possess significant toxicity to aquatic life. In situ immersion tests of coated stainless-steel nets with previously incorporated automotive paint products, LGPCs and ALPCs (1-O-octadecyl-2-O-acyl-sn-glycero-3-phosphocholine, ALPC18, and 1-O-hexadecyl-2-O-acyl-sn-glycero-3-phosphocholine, ALPC16), in an aquaculture reservoir in SP-Brazil revealed significant growth inhibition against macrofouling species, especially the epibiotic golden mussel (Limnoperna fortunei), when compared with the control. These results promise a more sustainable and ecologically innocuous approach to combating the biofouling phenomenon and the deeply concerning dissemination of the golden mussel which has provoked an economic crisis in the energy and aquaculture sectors.

5.
Mikrochim Acta ; 189(8): 307, 2022 08 02.
Article in English | MEDLINE | ID: mdl-35917034

ABSTRACT

The study aimed to develop an electrochemical sensor based on glassy carbon, mixed oxide (SiO2/TiO2/Sb2O5), and carbon black. The material was synthesized, characterized, and used to determine thiamethoxam in raw honey and water. The morphologic structure and electrochemical performance of the sensor was characterized by scanning electron microscopy and cyclic voltammetry. Differential pulse voltammetry with a concentration of 0.1 mol L-1 of Britton-Robinson buffer at pH 7.0 allowed the generation of a method to determine thiamethoxam in a linear range of 0.25 to 100.5 µmol L-1 and with a limit of detection of 0.012 µmol L-1. The system efficiently quantified traces of thiamethoxam in raw honey and tap water samples. The modified sensor did not present interferences of K+, Na+, Ca2+, Mg2+, glyphosate, imidacloprid, and carbendazim. In addition, the device showed good recovery values for thiamethoxam when applied directly to honey and water samples without any treatment, presenting an electrochemical sensor to monitor real-time hazardous substances in environmental and food matrices.


Subject(s)
Honey , Oxides , Electrochemical Techniques/methods , Electrodes , Limit of Detection , Oxides/chemistry , Silicon Dioxide , Soot , Thiamethoxam , Titanium , Water
6.
RSC Adv ; 10(2): 1050-1054, 2020 Jan 02.
Article in English | MEDLINE | ID: mdl-35494454

ABSTRACT

A chemoselective route for the synthesis of 1-O-alkylglycerols chimyl (1), batyl (2), and selachyl (3) is reported. These compounds can be naturally isolated from shark liver oil and the skin of animals such as stingrays and chimeras and exhibit potential anti-fouling activity. The synthetic approach developed in this work included two distinct methods of preparation. The first was based on solvent-free reactions catalyzed by onium quaternary salts (N and P) and ionic liquids; the second methodology was based on a series of one-pot reactions.

7.
J Sci Food Agric ; 99(9): 4248-4259, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30801730

ABSTRACT

BACKGROUND: Silver nanoparticles (AgNPs), particularly those entrapped in polymeric nanosystems, have arisen as options for managing plant bacterial diseases. Among the biopolymers useful for the entrapment of AgNPs, chitosan is promising because of its low cost, good biocompatibility, antimicrobial properties and biodegradability. The present study aimed: (i) to greenly-synthesize AgNPs using different concentrations of aqueous extract of tomato leaves followed by entrapment of AgNPs with chitosan (CH-AgNPs); (ii) to characterize the optical, structural and biological properties of the nanosystems produced; (iii) to evaluate the antimicrobial activities of AgNPs and nanomaterials; and (iv) to assess the effectiveness of AgNPs and nanomaterials for controlling tomato bacterial wilt caused by Ralstonia solanacearum. RESULTS: Spherical and oval AgNPs had incipient colloidal instability, although the concentration of the tomato leaf extract influenced both size (< 87 nm) and the polydispersity index. Nanomaterials (< 271 nm in size) were characterized by a highly stable matrix of chitosan containing polydisperse AgNPs. Free AgNPs and CH-AgNPs were stable for up to 30 days, with no significant alteration in physicochemical parameters. The AgNPs and nanomaterials had antibacterial activity and decreased bacterial growth at micromolar concentrations after 48 h. Morphological changes in R. solanacearum cells were observed after treatment with CH-AgNPs. The application of CH-AgNPs at 256 µmol L-1 reduced the incidence of bacterial wilt in a partially resistant tomato genotype but not in the susceptible line. CONCLUSION: Greenly-synthesized chitosan-derived nanomaterials containing AgNPs produced with leaf extracts from their own species appear to comprise a promising and sustainable alternative in an integrated management approach aiming to reduce the yield losses caused by bacterial wilt. © 2019 Society of Chemical Industry.


Subject(s)
Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/pharmacology , Chitosan/chemistry , Green Chemistry Technology/methods , Plant Diseases/microbiology , Plant Extracts/chemistry , Silver/pharmacology , Solanum lycopersicum/chemistry , Anti-Bacterial Agents/chemistry , Drug Carriers/chemistry , Drug Compounding , Solanum lycopersicum/microbiology , Nanostructures/chemistry , Plant Leaves/chemistry , Ralstonia/drug effects , Ralstonia/growth & development , Silver/chemistry
8.
Mar Pollut Bull ; 137: 702-710, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30503487

ABSTRACT

The objective of this study is to propose the use of specific synthetic lipid as an active substance (biocide) in the control of harmful aquatic microorganisms, such as pathogens and non-indigenous species, transported in ships' ballast water. The biocide candidate, without metal or halogen components, was produced from a sub-product of the edible oil industry, the lecithin. Laboratory assays were conducted with phytoplankton, zooplankton, and marine bacteria to evaluate the efficiency of the biocide. The study also considers specific biocide's characteristics related to environmental risks, such as chemical composition, persistence, bioaccumulation, and toxicity. Results showed that, in the first 24 h of treatment, the biocide effectively reduced the concentration of the planktonic micro-organisms to very low levels. Additionally, a preliminary risk evaluation pointed that biocide candidate has a low residual toxicity, also a low potential for persistence and bioaccumulation in the environment.


Subject(s)
Disinfectants/pharmacology , Lipids/pharmacology , Water Purification/methods , Bacteria/drug effects , Phytoplankton/drug effects , Plankton/drug effects
9.
Sci Rep ; 7(1): 17904, 2017 12 20.
Article in English | MEDLINE | ID: mdl-29263369

ABSTRACT

Degradation of cellular matrix is one of the important processes related to the progression of breast cancer. Tumor cells have the ability to exhibit necessary conditions for growth and survival, promoting degradation processes of extracellular matrix proteins, such as laminin (LN) and fibronectin (FN). In this study, we evaluated whether treatments, based on free rhodium (II) citrate (Rh2(H2cit)4), maghemite nanoparticles coated with citrate (Magh-cit) and maghemite nanoparticles coated with rhodium (II) citrate (Magh-Rh2(H2cit)4), in murine metastatic breast carcinoma models can modulate the expression of laminin and fibronectin proteins. Synthesized nanoparticles were characterized using X-ray diffraction, transmission electron microscopy, energy dispersive spectroscopy and dynamic light scattering. The expression of FN and LN was assessed using immunohistochemistry and western blotting. The gene expression of FN1 and LAMA1 were evaluated using real-time PCR. The FN1 and LAMA1 transcripts from the Magh-Rh2(H2cit)4 treated group were 95% and 94%, respectively, lower than the control group. Significant reduction in tumor volume for animals treated with Magh-Rh2(H2cit)4 was observed, of about 83%. We witnessed statistically significant reductions of FN and LN expression following treatment with Magh-Rh2(H2cit)4. We have demonstrated that the antitumor effects of Magh-Rh2(H2cit)4 and Rh2(H2cit)4 regulate the expression of FN and LN in metastatic breast tumors.


Subject(s)
Breast Neoplasms/drug therapy , Citric Acid/pharmacology , Ferric Compounds/pharmacology , Fibronectins/metabolism , Laminin/metabolism , Nanoparticles/administration & dosage , Rhodium/pharmacology , Animals , Breast/drug effects , Breast/metabolism , Breast Neoplasms/metabolism , Cell Line, Tumor , Disease Models, Animal , Extracellular Matrix Proteins/metabolism , Female , Mice , Mice, Inbred BALB C
10.
Int J Nanomedicine ; 12: 5511-5523, 2017.
Article in English | MEDLINE | ID: mdl-28814867

ABSTRACT

Nanocarriers have the potential to improve the therapeutic index of currently available drugs by improving their efficacy and achieving therapeutic steady-state levels over an extended period. The association of maghemite-rhodium citrate (MRC) nanoparticles (NPs) has the potential to increase specificity of the cytotoxic action. However, the interaction of these NPs with cells, their uptake mechanism, and subcellular localization need to be elucidated. This work evaluates the uptake mechanism of MRC NPs in metastatic and nonmetastatic breast cancer-cell models, comparing them to a nontumor cell line. MRC NPs uptake in breast cancer cells was more effective than in normal cells, with regard to both the amount of internalized material and the achievement of more strategic intracellular distribution. Moreover, this process occurred through a clathrin-dependent endocytosis pathway with different basal expression levels of this protein in the cell lines tested.


Subject(s)
Breast Neoplasms/drug therapy , Citrates/pharmacokinetics , Ferric Compounds/pharmacokinetics , Nanoparticles , Rhodium/pharmacokinetics , Breast Neoplasms/pathology , Cell Line, Tumor , Citric Acid/chemistry , Endocytosis/drug effects , Female , Humans , Microscopy, Electron, Transmission , Nanoparticles/chemistry , Rhodium/chemistry , Spectrum Analysis, Raman
11.
Rev. odontol. UNESP (Online) ; 46(4): 227-231, July-Aug. 2017. tab, ilus
Article in English | LILACS, BBO - Dentistry | ID: biblio-902656

ABSTRACT

Introduction: Blood is a biological material with high potential of infectious transmission in dental environments, including herpes simplex, hepatitis and AIDS. Aim: To investigate the efficacy of luminol in detecting blood in endodontic files before and after the sterilization process. Material and method: Luminol was used to investigate the presence or absence of traces of blood tissue in 50 endodontic files, visible to naked eye or not, after performing endodontic treatment and after the cleaning/sterilization process. The results obtained were tabulated and statistically analyzed by using the Friedman's test at a significance level of 5% (p<0.05). Result: By naked eye, it was found that 31/50 files showed no trace of blood, 8/50 showed a slight presence of blood and 11/50 showed a considerable presence of blood after endodontic treatment. After the use of luminol, however, 16/50 endodontic files showed no trace of blood, 19/50 showed a slight presence of blood and 15/50 showed a considerable presence of blood. After the cleaning and sterilization process, no blood was detected in the files. Conclusion: It was concluded that the luminol solution is effective in detecting blood tissue in endodontic files as well as in validating the cleaning/sterilization process.


Introdução: Sangue é um material biológico com alto potencial de transmissão de infecção em ambientes odontológicos, incluindo herpes simples, hepatites e AIDS. Objetivo: Investigar a eficácia do luminol em detector sangue em limas endodônticas antes e após o processo de esterilização. Material e método: Luminol foi utilizado para investigar a presença ou ausência de vestígios tecido sanguíneo em 50 limas endodônticas, visíveis ou não à olho nu, após a realização do tratamento endodôntico e após o processo de limpeza/esterilização. Os resultados obtidos foram tabulados e analisados estatisticamente utilizando o teste de Friedman com nível de significância de 5% (p<0,05). Resultado: A olho nú, foi observado que 31/50 limas não apresentaram vestígios de sangue, 8/50 apresentaram uma leve presença de sangue e 11/50 apresentaram uma presença considerável de sangue após o tratamento endodôntico. Após a utilização do luminol, entretanto, 16/50 limas endodônticas não apresentaram vestígios de sangue, 19/50 apresentaram uma leve presença de sangue e 15/50 apresentaram uma presença considerável de sangue. Após o processo de limpeza e esterilização não foi detectado sangue nas limas endodônticas. Conclusão: A solução de luminol é efetiva na detecção de tecido sanguíneo em limas endodônticas, validando o processo de limpeza/esterilização.


Subject(s)
Blood , Sterilization , Infection Control , Dental Clinics , Endodontics/instrumentation , Luminol , Therapeutics , Acquired Immunodeficiency Syndrome , Hepatitis , Herpes Zoster
12.
Theriogenology ; 86(5): 1165-74, 2016 Sep 15.
Article in English | MEDLINE | ID: mdl-27160447

ABSTRACT

Cryopreservation of ovarian cortex is potentially an important tool for the conservation of endangered species. It will allow preserving the large pool of primordial and primary follicles to retrieve fertilizable oocytes in the future. The aim of this study was to evaluate the effects of slow freezing on the morphology and viability of canine follicles after thawing using DMSO or 1,3-propanediol (PROH) as cryoprotectants. Slices of canine ovarian tissue were equilibrated for 20 minutes at 20 °C in minimum essential medium containing either cryoprotectants at 1.5 M, and then frozen by a standardized protocol. Morphology of follicles after thawing was analyzed by means of histology and transmission electron microscopy, and viability was assessed using Trypan blue and fluorescent probes. The exposure of dog ovarian tissue to both cryoprotectants before freezing had no effect on follicular morphology and viability. Also after freezing, follicles remained histologically normal, but transmission electron microscopy revealed damage of ultrastructure in follicles, which were exposed to PROH. Postthaw viability was significantly reduced with 65.7% of the follicles remaining alive in DMSO and 48.7% in PROH. In conclusion, this study demonstrated the survival of canine oocytes within ovarian cortex cryopreserved by slow freezing using 1.5-M DMSO.


Subject(s)
Cryopreservation/veterinary , Cryoprotective Agents/pharmacology , Dimethyl Sulfoxide/pharmacology , Dogs/physiology , Ovary/physiology , Propylene Glycols/pharmacology , Animals , Cell Survival , Female , Staining and Labeling
13.
Microb Pathog ; 86: 32-7, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26162295

ABSTRACT

Biofilms are microbial sessile communities attached to surfaces that are known for causing many medical problems. A bacterial biofilm of clinical relevance is formed by the gram-negative bacteria Pseudomonas aeruginosa. During the formation of a biofilm, the initial adhesion of the cells is of crucial importance, and the characteristics of the contact surface have great influence on this step. In the present study, we aimed to use matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) profiling as a new methodology to monitor P. aeruginosa biofilm development. Biofilms were grown within polypropylene tubes containing a glass slide, and were harvested after 3, 5, 7, 9, or 12 days of inoculation. Planktonic cells were obtained separately by centrifugation as control. Two independent MALDI-TOF experiments were performed, one by collecting biofilms from both the glass slide and the polypropylene tube internal surface, and the other by acquiring biofilms from these surfaces separately. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to evaluate the morphological progression of the biofilm. The molecular results showed that MALDI profiling is able not only to distinguish between different biofilm stages, but it is also appropriate to indicate when the biofilm cells are released at the dispersion stage, which occurred first on polypropylene surface. Finally, the present study pointed out that MALDI profiling may emerge as a promising tool for the clinical diagnostic and prognostic workup of biofilms formation and control.


Subject(s)
Bacterial Proteins/analysis , Biofilms/growth & development , Environmental Microbiology , Proteome/analysis , Pseudomonas aeruginosa/chemistry , Pseudomonas aeruginosa/physiology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Glass , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Polypropylenes , Pseudomonas aeruginosa/growth & development
14.
Toxicol Rep ; 2: 1086-1100, 2015.
Article in English | MEDLINE | ID: mdl-28962450

ABSTRACT

This study aimed to investigate potential acute and subchronic toxicity of rhodium (II) citrate in female Balb/c mice after intraperitoneal injections. In the acute test, independent groups received five doses; the highest dose (107.5 mg/kg) was equivalent to 33 times that used in our previous reports. The other doses were chosen as proportions of the highest, being 80.7 (75%), 53.8 (50%), 26.9 (25%) or 13.8 mg/kg (12.5%). Animals were monitored over 38 days and no severe signs of toxicity were observed, according to mortality, monitoring of adverse symptoms, hematological, biochemical and genotoxic parameters. We conclude that the median lethal dose (LD50) could be greater than 107.5 mg/kg. In the subchronic test, five doses of Rh2Cit (80, 60, 40, 20 or 10 mg/kg) were evaluated and injections were conducted on alternate days, totaling five applications per animal. Paclitaxel (57.5 mg/kg) and saline solution were controls. Clinical observations, histopathology of liver, lung and kidneys and effects on hematological, biochemistry and genotoxic records indicated that Rh2Cit induced no severe toxic effects, even at an accumulated dose up to 400 mg/kg.We suggest Rh2Cit has great potential as an antitumor drug without presenting acute and subchronic toxicity.

15.
Reprod Fertil Dev ; 27(3): 440-8, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25481978

ABSTRACT

Effective methods for gamete preservation should have low impact on DNA integrity. The present study investigated the effects of vitrification of goat ovarian tissues on the occurrence of DNA fragmentation and DNA double-stand breaks using the terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL) assay and detection of phosphorylated histone H2AX (γH2AX), respectively. Goat ovaries were collected at a local abattoir and 12 tissue fragments were prepared from each ovarian pair. Tissue fragments were used as fresh control samples or were cultured in vitro, vitrified or vitrified and cultured. Vitrification was performed using the Ovarian Tissue Cryosystem. Fragments from all groups (control and treatments) were processed for histology, transmission electron microscopy, TUNEL assay and immunofluorescence. Compared with fresh control samples, a lower percentage of morphologically normal follicles was detected in the vitrification followed by culture treatment group (P<0.05). Normal follicular ultrastructure was observed in all groups. Immunofluorescence revealed the presence of γH2AX foci in few oocytes and ovarian stromal cells. TUNEL-positive follicles were found in samples without significant differences among groups (P>0.05). In conclusion, the vitrification protocol used in the present study did not increase DNA damage in preantral follicles enclosed in goat ovarian tissues.


Subject(s)
Cryopreservation/methods , Cryoprotective Agents/pharmacology , DNA Damage/drug effects , Ovary/drug effects , Tissue Preservation/methods , Vitrification , Animals , Female , Goats , Ovarian Follicle/drug effects
16.
Homeopathy ; 102(1): 41-8, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23290878

ABSTRACT

OBJECTIVE: To evaluate the effect of dynamized follicle-stimulating hormone (FSH) on the survival, activation and growth of ovine preantral follicles (PFs) in vitro. METHODS: Ovarian fragments were cultured for 1 or 7 days in alpha minimum essential medium (α-MEM(+)) control in the absence or presence of alcohol (Al control) or FSH (6cH, 12cH and 30cH) added at intervals of 24 or 48 h. The ovarian fragments were processed, coded and analyzed by a blinded observer by classical histology (CH), fluorescence microscopy (FM) and transmission electron microscopy (TEM). RESULTS: After 7 days of culture, the group which to which FSH 6cH was added at 24 h intervals showed better rates of follicle survival and activation compared to α-MEM(+) control or Al control (p < 0.05). This group also showed higher follicle and oocyte growth than α-MEM(+) control (p < 0.05). FM and TEM techniques confirmed that FSH 6cH promoted viability and ultrastructural integrity of follicles after 7 days of culture. CONCLUSIONS: FSH 6cH (24 h) treatment maintained the viability, and promoted the activation and in vitro growth of ovine PFs.


Subject(s)
Follicle Stimulating Hormone/pharmacology , Ovarian Follicle/drug effects , Animals , Cell Culture Techniques , Cell Survival , Female , Microscopy, Electron, Transmission , Microscopy, Fluorescence , Oocytes/drug effects , Oocytes/growth & development , Oocytes/physiology , Ovarian Follicle/growth & development , Ovarian Follicle/physiology , Sheep
17.
Zygote ; 21(3): 295-304, 2013 Aug.
Article in English | MEDLINE | ID: mdl-21993013

ABSTRACT

Ovarian folliculogenesis in mammals is a complex process. Several compounds have been tested during in vitro culture of follicular cells for a better understanding of the mechanisms and factors related to ovarian folliculogenesis in mammals. From these compounds, vascular endothelial growth factor (VEGF) can be highlighted, as it is strongly associated with angiogenesis and, in recent years, its presence in ovarian cells has been investigated extensively. Previous studies have shown that the presence of VEGF protein, as well as mRNA expression of its receptor 2 (VEGFR-2) increases during follicular development. Therefore, it is likely that the interaction between VEGF and VEGFR-2 is crucial to promote follicular development. However, few studies on the influence of this factor on follicular development have been reported. This review addresses aspects related to the structural characterization and mechanism of action of VEGF and its receptors, and their biological importance in the ovary of mammals.


Subject(s)
Oocytes/physiology , Ovary/physiology , Vascular Endothelial Growth Factor A/physiology , Animals , Cell Survival , Female , Humans , Mammals , Ovary/blood supply , Ovary/cytology , Protein Structure, Tertiary , Receptors, Vascular Endothelial Growth Factor/chemistry , Receptors, Vascular Endothelial Growth Factor/metabolism , Vascular Endothelial Growth Factor A/chemistry
18.
Biol Reprod ; 87(3): 69, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22811569

ABSTRACT

The actions of different concentrations of insulin alone or in combination with follicle-stimulating hormone (FSH) were evaluated by in vitro follicular development and mRNA expression of cytochrome P450 aromatase (CYP19A1) and as receptors for insulin (INSR) and FSH (FSHR) from isolated, cultured goat preantral follicles. Goat preantral follicles were microdissected and cultured for 18 days in the absence or presence of insulin (5 and 10 ng/ml or 10 µg/ml) alone or in combination with FSH. After 18 days, the addition of the maximum concentration of insulin to the culture medium reduced follicular survival and antrum formation rates significantly compared to the other treatments. However, when FSH was added to the culture medium, no differences between these two parameters were observed. Preantral and antral follicles from the fresh control as well as from all cultured follicles still presented a normal ultrastructural pattern. In medium supplemented with FSH, only insulin at 10 ng/ml presented oocytes with higher rates of meiosis resumption compared to control, as well as oocytes in metaphase II. Treatment with insulin (10 ng/ml) plus FSH resulted in significantly increased levels of INSR and CYP19A1 mRNA compared to that with other treatments. In conclusion, 10 ng/ml insulin associated with FSH was more efficient in promoting resumption of oocyte meiosis, maintaining survival, stimulating follicular development, and increasing expression of the INSR and CYP19A1 genes in goat preantral follicles.


Subject(s)
Aromatase/genetics , Follicle Stimulating Hormone/pharmacology , Goats , Insulin/pharmacology , Ovarian Follicle/drug effects , Receptor, Insulin/genetics , Receptors, FSH/genetics , Animals , Aromatase/analysis , Aromatase/metabolism , Cells, Cultured , Female , Gene Expression Regulation, Developmental , Gene Expression Regulation, Enzymologic , Goats/genetics , Goats/metabolism , Goats/physiology , In Vitro Oocyte Maturation Techniques/methods , Ovarian Follicle/metabolism , Ovarian Follicle/physiology , Ovarian Follicle/ultrastructure , RNA, Messenger/analysis , RNA, Messenger/metabolism , Receptor, Insulin/analysis , Receptor, Insulin/metabolism , Receptors, FSH/analysis , Receptors, FSH/metabolism , Relative Value Scales
19.
Theriogenology ; 77(2): 260-7, 2012 Jan 15.
Article in English | MEDLINE | ID: mdl-21924476

ABSTRACT

The objective was to develop an efficient protocol for cryopreservation of agouti (Dasyprocta aguti) ovarian tissue. Agouti ovarian fragments were placed, for 10 min, in a solution containing MEM and fetal bovine serum plus 1.5 M dimethyl sulfoxide (DMSO), ethylene glycol (EG) or propanediol (PROH); some of those fragments were subsequently cryopreserved in a programmable freezer. After exposure and/or thawing, all samples were fixed in Carnoy prior to histological analysis. To evaluate ultrastructure, follicles from the control and all cryopreserved treatments were fixed in Karnovsky and processed for transmission electron microscopy. After exposure and freezing, there was a significant decrease in the percentage of morphologically normal preantral follicles in all treatments when compared to the control (92.67 ± 2.79, mean ± SD). However, there were no significant difference when the exposure and freezing procedures were compared using the same cryoprotectant. Moreover, there was no significant difference among cryoprotectants at the time of exposure (DMSO: 64.7 ± 3.8; EG: 70.7 ± 11.2, PROH: 63.3 ± 8.5) or after freezing (DMSO: 60.6 ± 3.6, EG: 64.0 ± 11.9; PROH: 62.0 ± 6.9). However, only follicles frozen with PROH had normal ultrastructure. In conclusion, preantral follicles enclosed in agouti ovarian tissue were successfully cryopreserved using 1.5 M PROH, with satisfactory maintenance of follicle morphology and ultrastructure.


Subject(s)
Cryopreservation/veterinary , Ovarian Follicle/ultrastructure , Rodentia/anatomy & histology , Tissue Preservation/veterinary , Animals , Cryopreservation/methods , Dimethyl Sulfoxide , Endangered Species , Ethylene Glycol , Female , Hearing , Microscopy, Electron, Transmission/veterinary , Models, Animal , Ovarian Follicle/physiology , Propylene Glycols , Tissue Preservation/methods
20.
Zygote ; 19(3): 215-27, 2011 Aug.
Article in English | MEDLINE | ID: mdl-20979684

ABSTRACT

The aim of this study was to evaluate the influence of the number of follicles per drop (one or three) and antral follicles on in vitro development of isolated goat preantral follicles. Preantral follicles were isolated through microdissection and distributed individually (control) or in groups of three follicles (treatment) in microdroplets of α-MEM with or without 1000 ng/ml follicle stimulating hormone (FSH) for Experiments 1 and 2, respectively. Experiment 3 was divided into four treatments according to the presence of one or three preantral follicles, associated or not with antral follicles. After culture, oocytes were retrieved from morphologically normal follicles and submitted to in vitro maturation (IVM) and live/dead fluorescent labelling. Results of Experiment 1 (basic medium without FSH) showed that culture of preantral follicles in groups enhances viability, growth and antrum formation after 12 days. However, in the presence of FSH (Experiment 2), only the recovery rate of fully grown oocytes for IVM was significantly affected by grouping of follicles. In Experiment 3, in general, co-culture of preantral follicles with an early antral follicle had a detrimental effect on viability, antrum formation and production of oocytes for IVM. In conclusion, the performance of in vitro culture of goat preantral follicles is affected by the number of follicles per drop, the presence of an antral follicle and FSH.


Subject(s)
Follicle Stimulating Hormone/pharmacology , Ovarian Follicle/cytology , Ovarian Follicle/physiology , Animals , Cell Survival/drug effects , Cells, Cultured , Culture Media , Female , Goats , Hormones/pharmacology , In Vitro Techniques , Oocytes/cytology , Oocytes/drug effects , Ovarian Follicle/drug effects
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