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1.
Med Sci Monit ; 30: e942836, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38632864

ABSTRACT

BACKGROUND Patients with urolithiasis often undergo transurethral ureteroscopic holmium laser lithotripsy, a procedure that can be affected by perioperative thermal management. This study examines the impact of compound thermal insulation management on patient recovery and comfort during transurethral ureteroscopic holmium laser lithotripsy. MATERIAL AND METHODS In this study, 551 patients who underwent transurethral ureteroscopic holmium laser lithotripsy from April 2019 to December 2022 were randomly assigned to either an observation group (n=276) or control group (n=275). Both groups received routine surgical care, with the observation group additionally receiving compound thermal insulation management. We recorded and compared perioperative body temperature changes, anesthetic resuscitation indicators (bispectral index recovery time, extubation time, fully awake time, Postanesthesia Care Unit retention time), comfort level (General Comfort Questionnaire), and quality of life (Nottingham Health Profile). We also compared the incidence of complications. RESULTS There was no significant difference in body temperature between groups at the start surgery. However, the observation group showed significantly higher temperatures during and at the end of surgery. Anesthetic resuscitation indicators were significantly better in the observation group. Both groups showed improved comfort and quality of life after surgery, with more significant improvements in the observation group. The observation group also had a lower incidence of complications, such as hypothermia and rigor. CONCLUSIONS Compound thermal insulation management during transurethral ureteroscopic holmium laser lithotripsy improved perioperative temperature maintenance, accelerated postoperative recovery, reduced complication rates, and enhanced patient comfort and quality of life.


Subject(s)
Anesthetics , Lasers, Solid-State , Lithotripsy, Laser , Lithotripsy , Humans , Lithotripsy, Laser/methods , Holmium , Quality of Life , Ureteroscopy/methods
2.
Ultrason Sonochem ; 102: 106742, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38171196

ABSTRACT

Extracting polyphenolic bioactive compounds from Pinus elliottii needles, a forestry residue, promises economic and environmental benefits, however, relevant experimental data are lacking. Herein, a comprehensive investigation of the polyphenolic composition of pine needles (PNs) was carried out. Ultrasound-Assisted Extraction (UAE) was applied to extract the polyphenolic compounds of pine needles. The optimal conditions of extracts were determined by Response Surface Methodology (RSM). The maximum total phenolic content (TPC) of 40.37 mg GAE/g PNs was achieved with solid-liquid ratio of 1:20, 60 % ethanol, and 350 W for 25 min at 45 °C. Polyphenolic extracts showed antioxidant activity in scavenging free radicals and reducing power (DPPH, IC50 41.05 µg/mL; FRAP 1.09 mM Fe2+/g PNs; ABTS, IC50 214.07 µg/mL). Furthermore, the second-order kinetic model was also constructed to describe the mechanism of the UAE process, with the extraction activation energy estimated at 12.26 kJ/mol. In addition, 37 compounds in PNs were first identified by UHPLC-Q-Exactive Orbitrap MS/MS, including flavonoids and phenolic acids. The results suggest that Ultrasound-Assisted is an effective method for the extraction of natural polyphenolic compounds from pine needles and this study could serve as a foundation for utilizing phenolics derived from PNs in the food and pharmaceutical industries.


Subject(s)
Pinus , Polyphenols , Polyphenols/analysis , Antioxidants/chemistry , Tandem Mass Spectrometry , Chromatography, High Pressure Liquid , Phenols/analysis , Plant Extracts/chemistry
3.
Food Sci Nutr ; 11(4): 2049-2060, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37051347

ABSTRACT

Okra pod is sensitive to low temperature, which results in chilling injury under improper low-temperature storage. This study aimed to evaluate the effect of different concentrations of methyl jasmonate (MeJA) treatment on okra pod stored at 4 ± 1°C for 12 days and illuminate the mechanism of MeJA alleviating chilling injury. Compared to the control, MeJA treatments maintained lower relative electric conductivity (REC), chilling injury (CI) degree, and lignin content, as well as higher total soluble solids, total soluble sugar, pectin content, and chlorophyll content. The factor analysis was applied to comprehensively evaluate the effects of MeJA so that 1 µmol/L MeJA was screened as the optimum concentration to maintain the okra quality throughout the storage time. In contrast with control, MeJA not only accelerated the generation of antioxidant substances (phenolics and flavonoids) but also increased the superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) activity, inhibited malondialdehyde (MDA), hydrogen peroxide (H2O2) content accumulation, and the polyphenol oxidase (PPO) activity. This work confirmed that MeJA could effectively alleviate chilling injury and maintain the quality during cold-stored by regulating reactive oxygen species (ROS) metabolism. These results provide theoretical guidance for the application of MeJA in okra storage and preservation.

4.
Nanomaterials (Basel) ; 13(1)2022 Dec 30.
Article in English | MEDLINE | ID: mdl-36616085

ABSTRACT

Bound solitons have become a hot topic in the field of nonlinear optics due to their potential applications in optical communication, information processing and radar systems. However, the trapping of the cascaded bound soliton is still a major challenge up to now. Here, we propose and experimentally demonstrate a multi-pulse bound soliton fiber laser based on MoTe2 saturable absorber. In the experiment, MoTe2 nanosheets were synthesized by chemical vapor deposition and transferred to the fiber taper by optical deposition. Then, by inserting the MoTe2 saturable absorber into a ring cavity laser, the two-pulse, three-pulse and four-pulse bound solitons can be stably generated by properly adjusting the pump strength and polarization state. These cascaded bound solitons are expected to be applied to all-optical communication and bring new ideas to the study of soliton lasers.

5.
J Am Heart Assoc ; 5(1)2016 Jan 06.
Article in English | MEDLINE | ID: mdl-26738788

ABSTRACT

BACKGROUND: Circulating angiogenic cells (CACs) are peripheral blood cells whose functional capacity inversely correlates with cardiovascular risk and that have therapeutic benefits in animal models of cardiovascular disease. However, donor age and disease state influence the efficacy of autologous cell therapy. We sought to determine whether age or coronary artery disease (CAD) impairs the therapeutic potential of CACs for myocardial infarction (MI) and whether the use of ex vivo gene therapy to overexpress endothelial nitric oxide (NO) synthase (eNOS) overcomes these defects. METHODS AND RESULTS: We recruited 40 volunteers varying by sex, age (< or ≥45 years), and CAD and subjected their CACs to well-established functional tests. Age and CAD were associated with reduced CAC intrinsic migration (but not specific response to vascular endothelial growth factor, adherence of CACs to endothelial tubes, eNOS mRNA and protein levels, and NO production. To determine how CAC function influences therapeutic potential, we injected the 2 most functional and the 2 least functional CAC isolates into mouse hearts post MI. The high-function isolates substantially improved cardiac function, whereas the low-function isolates led to cardiac function only slightly better than vehicle control. Transduction of the worst isolate with eNOS cDNA adenovirus increased NO production, migration, and cardiac function of post-MI mice implanted with the CACs. Transduction of the best isolate with eNOS small interfering RNA adenovirus reduced all of these capabilities. CONCLUSIONS: Age and CAD impair multiple functions of CACs and limit therapeutic potential for the treatment of MI. eNOS gene therapy in CACs from older donors or those with CAD has the potential to improve autologous cell therapy outcomes.


Subject(s)
Coronary Artery Disease/enzymology , Endothelial Progenitor Cells/enzymology , Endothelial Progenitor Cells/transplantation , Myocardial Infarction/surgery , Neovascularization, Physiologic , Nitric Oxide Synthase Type III/metabolism , Nitric Oxide/metabolism , Stem Cell Transplantation/methods , Adult , Aged , Animals , Case-Control Studies , Cell Movement , Cells, Cultured , Coculture Techniques , Coronary Artery Disease/diagnosis , Disease Models, Animal , Female , Humans , Male , Mice, SCID , Middle Aged , Myocardial Infarction/enzymology , Myocardial Infarction/genetics , Myocardial Infarction/pathology , Myocardial Infarction/physiopathology , Nitric Oxide Synthase Type III/genetics , Phenotype , RNA Interference , Recovery of Function , Regeneration , Signal Transduction , Time Factors , Transduction, Genetic , Transfection
6.
Redox Biol ; 2: 156-64, 2014.
Article in English | MEDLINE | ID: mdl-25460726

ABSTRACT

The zinc tetrathiolate (ZnS4) cluster is an important structural feature of endothelial nitric oxide synthase (eNOS). The cluster is located on the dimeric interface and four cysteine residues (C94 and C99 from two adjacent subunits) form a cluster with a Zn ion in the center of a tetrahedral configuration. Due to its high sensitivity to oxidants this cluster is responsible for eNOS dimer destabilization during periods of redox stress. In this work we utilized site directed mutagenesis to replace the redox sensitive cysteine residues in the ZnS4 cluster with redox stable tetra-arginines. Our data indicate that this C94R/C99R eNOS mutant is active. In addition, this mutant protein is insensitive to dimer disruption and inhibition when challenged with hydrogen peroxide (H2O2). Further, the overexpression of the C94R/C99R mutant preserved the angiogenic response in endothelial cells challenged with H2O2. The over-expression of the C94R/C99R mutant preserved the ability of endothelial cells to migrate towards vascular endothelial growth factor (VEGF) and preserved the endothelial monolayer in a scratch wound assay. We propose that this dimer stable eNOS mutant could be utilized in the treatment of diseases in which there is eNOS dysfunction due to high levels of oxidative stress.


Subject(s)
Amino Acid Substitution , Hydrogen Peroxide/chemistry , Mutation, Missense , Nitric Oxide Synthase Type III , Animals , COS Cells , Chlorocebus aethiops , Humans , Nitric Oxide Synthase Type III/chemistry , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type III/metabolism
7.
Nicotine Tob Res ; 16(5): 584-90, 2014 May.
Article in English | MEDLINE | ID: mdl-24302638

ABSTRACT

INTRODUCTION: We sought to determine the effects of brief exposures to low concentrations of tobacco secondhand smoke (SHS) on arterial flow-mediated dilation (FMD, a nitric oxide-dependent measure of vascular endothelial function), in a controlled animal model never before exposed to smoke. In humans, SHS exposure for 30 min impairs FMD. It is important to gain a better understanding of the acute effects of exposure to SHS at low concentrations and for brief periods of time. METHODS: We measured changes in FMD in rats exposed to a range of real-world levels of SHS for durations of 30 min, 10 min, 1 min, and 4 breaths (roughly 15 s). RESULTS: We observed a dose-response relationship between SHS particle concentration over 30 min and post-exposure impairment of FMD, which was linear through the range typically encountered in smoky restaurants and then saturated at higher concentrations. One min of exposure to SHS at moderate concentrations was sufficient to impair FMD. CONCLUSIONS: Brief SHS exposure at real-world levels reversibly impairs FMD. Even 1 min of SHS exposure can cause reduction of endothelial function.


Subject(s)
Endothelium, Vascular/drug effects , Endothelium, Vascular/physiopathology , Tobacco Smoke Pollution/adverse effects , Animals , Dilatation, Pathologic , Disease Models, Animal , Dose-Response Relationship, Drug , Female , Femoral Artery/physiopathology , Humans , Rats , Rats, Sprague-Dawley , Time Factors
8.
J Appl Physiol (1985) ; 114(6): 752-60, 2013 Mar 15.
Article in English | MEDLINE | ID: mdl-23349456

ABSTRACT

Nitric oxide (NO) exerts a wide range of cellular effects in the cardiovascular system. NO is short lived, but S-nitrosoglutathione (GSNO) functions as a stable intracellular bioavailable NO pool. Accordingly, increased levels can facilitate NO-mediated processes, and conversely, catabolism of GSNO by the regulatory enzyme GSNO reductase (GSNOR) can impair these processes. Because dysregulated GSNOR can interfere with processes relevant to cardiovascular health, it follows that inhibition of GSNOR may be beneficial. However, the effect of GSNOR inhibition on vascular activity is unknown. To study the effects of GSNOR inhibition on endothelial function, we treated rats with a small-molecule inhibitor of GSNOR (N6338) that has vasodilatory effects on isolated aortic rings and assessed effects on arterial flow-mediated dilation (FMD), an NO-dependent process. GSNOR inhibition with a single intravenous dose of N6338 preserved FMD (15.3 ± 5.4 vs. 14.2 ± 6.3%, P = nonsignificant) under partial NO synthase inhibition that normally reduces FMD by roughly 50% (14.1 ± 2.9 vs. 7.6 ± 4.4%, P < 0.05). In hypertensive rats, daily oral administration of N6338 for 14 days reduced blood pressure (170.0 ± 5.3/122.7 ± 6.4 vs. 203.8 ± 1.9/143.7 ± 7.5 mmHg for vehicle, P < 0.001) and vascular resistance index (1.5 ± 0.4 vs. 3.2 ± 1.0 mmHg · min · l(-1) for vehicle, P < 0.001), and restored FMD from an initially impaired state (7.4 ± 1.7%, day 0) to a level (13.0 ± 3.1%, day 14, P < 0.001) similar to that observed in normotensive rats. N6338 also reversed the pathological kidney changes exhibited by the hypertensive rats. GSNOR inhibition preserves FMD under conditions of impaired NO production and protects against both microvascular and conduit artery dysfunction in a model of hypertension.


Subject(s)
Aldehyde Oxidoreductases/antagonists & inhibitors , Antihypertensive Agents/pharmacology , Endothelium, Vascular/drug effects , Enzyme Inhibitors/pharmacology , Femoral Artery/drug effects , Hypertension/drug therapy , Vasodilation/drug effects , Vasodilator Agents/pharmacology , Administration, Oral , Aldehyde Oxidoreductases/metabolism , Animals , Antihypertensive Agents/administration & dosage , Blood Pressure/drug effects , Cells, Cultured , Disease Models, Animal , Dose-Response Relationship, Drug , Endothelium, Vascular/enzymology , Endothelium, Vascular/physiopathology , Enzyme Inhibitors/administration & dosage , Femoral Artery/enzymology , Femoral Artery/physiopathology , Humans , Hypertension/enzymology , Hypertension/etiology , Hypertension/pathology , Hypertension/physiopathology , Injections, Intravenous , Kidney/drug effects , Kidney/pathology , Mice , Nitric Oxide/metabolism , Nitric Oxide Synthase Type III/antagonists & inhibitors , Nitric Oxide Synthase Type III/metabolism , Rats , Rats, Inbred Dahl , Rats, Sprague-Dawley , Sodium Chloride, Dietary , Time Factors , Vasodilator Agents/administration & dosage
9.
Am J Cardiovasc Dis ; 2(1): 12-9, 2012.
Article in English | MEDLINE | ID: mdl-22254209

ABSTRACT

BACKGROUND: Chronic or severe acute elevations in plasma glucose are associated with decreases in the number and function of circulating angiogenic cells (CACs). However, less is known about whether fasting plasma glucose levels (FPG) within the normal or pre-diabetic range among healthy individuals are associated with decreased CAC function. Establishing this relationship is an important step in developing a line of research that may ultimately lead to preventative lifestyle interventions intended to maximize endogenous CAC function and reduce cardiometabolic disease risk. OBJECTIVES: 1) To examine whether increases in FPG are associated with decreases in CAC migration among healthy individuals with FPG levels below the threshold for hyperglycemia, and 2) to contrast effect of FPG on CAC migration toward a pro-angiogenic stimulus (vascular endothelial growth factor; VEGF) with effect on intrinsic cell migratory capacity (i.e., random migration with no stimulus). METHODS: 28 men and women ranging from 20-57 years of age and free of cardiovascular disease participated in a pilot study, involving a fasting blood draw for FPG and isolation of peripheral blood mononuclear cells. CAC migration toward VEGF and random cell migration (control) were assessed in vitro. VEGF-induced migration that was normalized to control migration, representing the VEGF-response component of chemotaxis independent of motility, was calculated to determine whether any impairment in migration to VEGF was due to lower specific response to VEGF or to lower non-specific migratory capacity. RESULTS: Increased levels of FPG were associated in a dose-response fashion with a significantly lower random migration under control conditions (CTRL: r= -.408, p=.031), no differences in migration to VEGF (r= -.039, p=.842) and a borderline association with VEGF-induced migration normalized to control migration (VEGF/CTRL: r=.349, p=.069). The relationship between FPG and random migration under control conditions remained significant when controlling for gender and body mass index (p's<.05), and became borderline significant when controlling for age (p=.062). CONCLUSIONS: Among healthy individuals, higher fasting glucose levels, despite falling below the diabetic range, are associated with decreased random CAC migration. These findings suggest a need for further studies investigating the effects of lifestyle or dietary interventions on glucose regulation and CAC function.

10.
Arterioscler Thromb Vasc Biol ; 30(11): 2212-8, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20705916

ABSTRACT

OBJECTIVE: Circulating angiogenic cells (CACs), also termed endothelial progenitor cells, play an integral role in vascular repair and are functionally impaired in coronary artery disease (CAD). The role of nitric oxide (NO) in CAC function is poorly understood. We hypothesized that CAC migration toward angiogenic signals is modulated by both NO synthase (NOS) expression and functional response to NO. METHODS AND RESULTS: Similar to endothelial cells, CAC chemotaxis to vascular endothelial growth factor (VEGF) was blocked by inhibition of NOS, phosphatidylinositol 3-kinase, or guanylyl cyclase or by treatment with an NO scavenger. Addition of an NO donor (S-nitroso-N-acetylpenicillamine) and the NOS substrate l-arginine increased random cell migration (chemokinesis) and enhanced VEGF-dependent chemotaxis. Healthy CACs expressed endothelial NOS, but endothelial NOS was not detected in CAD patient CACs. Both chemokinesis and chemotaxis to VEGF of patient CACs were decreased compared with healthy CACs but were restored to healthy values by S-nitroso-N-acetylpenicillamine. In parallel, CAD patients exhibited lower flow-mediated vasodilation and plasma NO source nitrite than young, healthy subjects, indicating endothelial dysfunction with reduced NO bioavailability. CONCLUSIONS: NOS activity is required for CAC chemotaxis. In CAD patients, impairment of NOS expression and NO bioavailability, rather than response to NO, may contribute to dysfunction of CACs and limit their regenerative capacity.


Subject(s)
Chemotaxis/physiology , Endothelial Cells/physiology , Nitric Oxide Synthase/biosynthesis , Nitric Oxide/physiology , Stem Cells/physiology , Vascular Endothelial Growth Factor A/metabolism , Cell Movement , Humans , Neovascularization, Physiologic
11.
Endocrinology ; 151(1): 281-90, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19887564

ABSTRACT

The frequency of intrinsic pulsatile GnRH secretion from endogenous GnRH neurons and GT1 GnRH cell lines is stimulated by increased intracellular cAMP levels. The downstream molecules comprising the cAMP signaling pathway are organized in microdomains by a family of scaffolding proteins, A-kinase anchoring proteins (AKAPs). These molecules tether protein kinase A, cAMP-specific phosphodiesterases, phosphatases to known substrates. In neurons AKAP150 organizes many of the signaling molecules known to regulate the excitability and intrinsic pulsatile activity of GnRH neurons. AKAP150 was expressed in both the GT1-1 and GT1-7 cells. We determined the role of AKAP150 in coordinating GT1-1 cell excitability and intrinsic GnRH pulsatile secretion by lowering AKAP150 levels with a small interfering RNA (siRNA) adenovirus construct to AKAP150 (Ad-AKAP150-siRNA). Infection with Ad-AKAP150-siRNA specifically decreased AKAP150 mRNA levels by 74% and protein levels by 53% relative to uninfected cells or cells infected with a luciferase control adenovirus siRNA vector. In GT1 cells, spontaneous Ca(2+) oscillations, an index of neuron excitability, are stimulated by increased levels of intracellular cAMP and lowered by decreased levels. The frequency of spontaneous Ca(2+) oscillations in Ad-AKAP150-siRNA-treated GT1-1 cells decreased by 47.2% relative to controls. A dramatic decrease in the number of spontaneous GnRH pulses was also observed after infection with Ad-AKAP150-siRNA. The interpulse interval increased to 143 +/- 20.25 min in Ad-AKAP150-siRNA infected cells from 32.2 +/- 7.3 min in luciferase control adenovirus siRNA vector-infected cells. These data demonstrate an important role of AKAP150 in coordinating signaling events regulating the frequency of intrinsic pulsatile GnRH secretion.


Subject(s)
A Kinase Anchor Proteins/genetics , Gonadotropin-Releasing Hormone/metabolism , Neurons/metabolism , Neurons/physiology , Synaptic Transmission/genetics , A Kinase Anchor Proteins/antagonists & inhibitors , A Kinase Anchor Proteins/physiology , Animals , COS Cells , Calcium Signaling/drug effects , Calcium Signaling/genetics , Cells, Cultured , Chlorocebus aethiops , Down-Regulation/drug effects , Down-Regulation/genetics , Down-Regulation/physiology , Mice , Neurons/drug effects , Pulsatile Flow/drug effects , RNA, Small Interfering/pharmacology , Synaptic Transmission/drug effects
12.
Am J Physiol Heart Circ Physiol ; 294(2): H1086-93, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18055528

ABSTRACT

In humans, endothelial vasodilator function serves as a surrogate marker for cardiovascular health and is measured as changes in conduit artery diameter after temporary ischemia [flow-mediated dilation (FMD)]. Here we present an FMD-related approach to study femoral artery (FA) vasodilation in anesthetized rats. Diameter and Doppler flow were monitored in the FA. Using high-resolution ultrasound (35 MHz) and automated analysis software, we detected dose-dependent vasodilation using established endothelium-independent [intravenous nitroglycerin EC(50) = 3.3 x 10(-6) mol/l, peak 21Delta% (SD 4)] and endothelium-dependent [intra-arterial acetylcholine EC(50) = 1.3 x 10(-6) mol/l, peak 27Delta% (SD 4)] pharmacological vasodilators. Wall shear stress induced by intra-aortic injection of adenosine and infusion of saline at increasing rates (1.5-4.5 ml/min) led to vasodilation at 1 to 2 min. Transient hindlimb ischemia by common iliac occlusion (5 min) led to reactive hyperemia with flow velocity and wall shear stress increase and was followed by FA dilation [16Delta% (SD 2)], the latter of which was completely abolished by nitric oxide synthase (NOS) inhibition with N(G)-monomethyl-L-arginine [1Delta% (SD 2)]. FMD was significantly reduced in adult 20-24-wk-old animals compared with 9- to 10-wk-old animals, consistent with age-dependent endothelial dysfunction [16Delta% (SD 3) vs. 10Delta% (SD 3), P < 0.05]. Whereas FMD was completely NOS dependent in 9- to 10-wk-old animals, NOS-dependent mechanisms accounted for only half of the FMD in 20-24-wk-old animals, with the remainder being blocked by charybdotoxin and apamin, suggesting a contribution of endothelium-derived hyperpolarizing factor. To our knowledge, this is the first integrative physiological model to reproducibly study FMD of conduit arteries in living rats.


Subject(s)
Echocardiography , Vasodilation/physiology , Adenosine/pharmacology , Aging/physiology , Animals , Dose-Response Relationship, Drug , Femoral Artery/diagnostic imaging , Femoral Artery/drug effects , Femoral Artery/physiology , Hindlimb/blood supply , Hyperemia/diagnostic imaging , Hyperemia/physiopathology , Ischemia/diagnostic imaging , Ischemia/physiopathology , Male , Nitric Oxide Synthase/physiology , Nitroglycerin/pharmacology , Rats , Rats, Sprague-Dawley , Regional Blood Flow/drug effects , Regional Blood Flow/physiology , Reproducibility of Results , Stress, Mechanical , Vasodilation/drug effects , Vasodilator Agents/pharmacology
13.
Endocrinology ; 146(2): 808-15, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15528299

ABSTRACT

Recent studies have shown the involvement of Fas/Fas ligand (FasL) system and nitric oxide (NO) in ovarian follicle atresia. Here we asked whether Fas/Fas ligand system interacts with NO using rat granulosa cell culture. Soluble recombinant Fas ligand (rFasL), at 100 ng/ml, significantly decreased cell viability, as measured by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay, in the presence of 200 U/ml interferon-gamma, whereas the concurrent addition of a caspase inhibitor, Z-VAD-FMK, at 20 microm, significantly inhibited rFasL-induced cytotoxicity. Hoechst 33342 staining and flow cytometric analysis confirmed the induction of apoptosis in granulosa cells by 100 ng/ml rFasL in the presence of interferon-gamma, which was blocked by the concomitant addition of an NO donor, S-nitroso-N-acetylpenicillamine. Western blot analysis demonstrated that rFasL significantly up-regulated caspase-3, -8, and -9 activities in granulosa cells, which were attenuated by concurrent treatment with S-nitroso-N-acetylpenicillamine. Real-time quantitative RT-PCR revealed a significant decrease in inducible NO synthase mRNA levels in rFasL-induced apoptotic granulosa cells. In conclusion, we demonstrated the involvement of Fas/FasL system in inducing apoptosis through activation of a caspase-mediated cascade in rat granulosa cells, which is coupled with a decrease in inducible NO synthase expression. We further showed that NO inhibited Fas/FasL system-induced apoptosis by suppressing activation of the caspases, pointing to a cross-talk between Fas/FasL system-induced apoptosis pathway and NO-mediated antiapoptotic pathway in ovarian follicle atresia.


Subject(s)
Apoptosis/physiology , Follicular Atresia/metabolism , Granulosa Cells/cytology , Membrane Glycoproteins/metabolism , Nitric Oxide/metabolism , Penicillamine/analogs & derivatives , fas Receptor/metabolism , Animals , Apoptosis/drug effects , Caspases/metabolism , Cell Survival/physiology , Cells, Cultured , Fas Ligand Protein , Female , Granulosa Cells/metabolism , Nitric Oxide Donors/pharmacology , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II , Penicillamine/pharmacology , Rats , Rats, Wistar , Receptor Cross-Talk/physiology
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