ABSTRACT
We hypothesized that HIV-1 may enter tubular cells by phagocytosis of apoptotic fragments of HIV-1-infected T cells infiltrating tubular interstitium. The study was designed to evaluate the interaction of programmed death-1 (PD-1) receptors on CD4 T cells and programmed death ligand-1 (PD-L1) on tubular cells (HK2 and HRPTEC, primary tubular cells). Co-cultivation of HIV-1 infected lymphocytes (HIV-LY) with HK2s/HRPTECs resulted in T cell apoptosis, uptake of the apoptosed HIV-LY by HK2s/HRPTECs, tubular cell activation and HIV expression. Cytochalasin-B inhibited tubular cell HIV-LY uptake and anti-PD-L1 antibody inhibited HIV-LY apoptosis and tubular cell HIV-LY uptake, activation and HIV expression. These observations do indicate induction of apoptosis of T cells due to interaction of PD-1 and PD-L1 upon co-cultivation and subsequent phygocytosis of HIV-laden apoptotic bodies by tubular cells and thus the transfer of HIV-1 into tubular cells. These findings identify a novel pathway that facilitates HIV-1 entry into tubular cell.
Subject(s)
Apoptosis , CD4-Positive T-Lymphocytes/virology , Epithelial Cells/physiology , Epithelial Cells/virology , HIV-1/physiology , Phagocytosis , Virus Internalization , Cells, Cultured , Coculture Techniques , HumansABSTRACT
An infectious etiology has been proposed for many human cancers, but rarely have specific agents been identified. One difficulty has been the need to propagate cancer cells in vitro to produce the infectious agent in detectable quantity. We hypothesized that genome amplification from small numbers of cells could be adapted to circumvent this difficulty. A patient with concomitant chronic lymphocytic leukemia (CLL) and polycythemia vera (PV) requiring therapeutic phlebotomy donated a large amount of phlebotomized blood to test this possibility. Using genome amplification methods, we identified a new isolate (BIS8-17) of torque teno virus (TTV) 10. The presence of blood isolate sequence 8-17 (BIS8-17) in the original plasma was confirmed by polymerase chain reaction (PCR), validating the approach, since TTV is a known plasma virus. Subsequent PCR testing of plasmas from additional patients showed that BIS8-17 had a similar incidence (~20%) in CLL (n = 48) or PV (n = 10) compared with healthy controls (n = 52). CLL cells do not harbor BIS8-17; PCR did not detect it in CLL peripheral blood genomic deoxyribonucleic acid (DNA) (n = 20). CLL patient clinical outcome or prognostic markers (immunoglobulin heavy chain variable region [IGHV ] mutation, CD38 or zeta-chain associated protein kinase 70 kDa [ZAP-70]) did not correlate with BIS8-17 infection. Although not causative to our knowledge, this is the first reported isolation and detection of TTV in either CLL or PV. TTV could serve as a covirus with another infectious agent or TTV variant with rearranged genetic components that contribute to disease pathogenesis. These results prove that this method identifies infectious agents and provides an experimental methodology to test correlation with disease.
Subject(s)
Genome, Viral/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/complications , Nucleic Acid Amplification Techniques/methods , Polycythemia Vera/complications , Polycythemia Vera/virology , Torque teno virus/genetics , Torque teno virus/isolation & purification , Aged , Aged, 80 and over , Blood Donors , Case-Control Studies , DNA Virus Infections/blood , DNA Virus Infections/complications , DNA Virus Infections/virology , DNA, Viral/blood , DNA, Viral/genetics , Female , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/blood , Leukemia, Lymphocytic, Chronic, B-Cell/virology , Male , Middle Aged , Polycythemia Vera/blood , Reproducibility of ResultsSubject(s)
Basophils/pathology , Cardiovascular Diseases/etiology , Leukemia, Basophilic, Acute/diagnosis , Proto-Oncogene Proteins c-ets/genetics , Repressor Proteins/genetics , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Marrow Examination , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/therapy , Electrocardiography , Fatal Outcome , Female , Humans , In Situ Hybridization, Fluorescence , Leukemia, Basophilic, Acute/complications , Leukemia, Basophilic, Acute/drug therapy , Leukemia, Basophilic, Acute/genetics , Leukemia, Basophilic, Acute/pathology , Multiple Organ Failure/etiology , Respiratory Insufficiency/etiology , Treatment Outcome , ETS Translocation Variant 6 ProteinABSTRACT
Podocytes are an integral and important constituent of the glomerular filtration barrier (GFB) and are exposed to a higher concentrations of ANG II in diseased states; consequently, podocytes may accumulate oxidized proteins and damaged mitochondria. In the present study, we evaluated the effect of ANG II on the podocyte autophagic process, which is likely to be triggered in order to degrade unwanted proteins and damaged organelles. To quantitate the occurrence of autophagy, electron microscopic studies were carried out on control and ANG II-treated conditionally immortalized mouse podocytes (CIMPs). ANG II-treated cells showed a fivefold greater number of autophagosomes/field compared with control cells. This proautophagic effect of ANG II was inhibited by pretreatment with 3-methyladenine, an inhibitor of autophagy. ANG II also enhanced podocyte expression of autophagic genes such as LC3-2 and beclin-1. Since oxidative stress is often associated with the induction of autophagy, we examined the effect of ANG II on podocyte reactive oxygen species (ROS) generation. ANG II enhanced podocyte ROS generation in a time-dependent manner. To determine whether there is a causal relationship between ANG II-induced oxidative stress and induction of autophagy, we evaluated the effect of antioxidants on ANG II-induced autophagy. As expected, the proautophagic effect of ANG II was inhibited by antioxidants. We conclude that ANG II promotes podocyte autophagy through the generation of ROS.
Subject(s)
Angiotensin II/physiology , Autophagy/physiology , Podocytes/physiology , Angiotensin II/genetics , Animals , Apoptosis/genetics , Apoptosis/physiology , Autophagy/genetics , Cell Line, Transformed , Mice , Oxidative Stress/genetics , Oxidative Stress/physiology , Podocytes/ultrastructure , Reactive Oxygen Species/metabolismABSTRACT
RATIONALE: The ubiquitin proteasome system (UPS) becomes dysfunctional as a result of ischemia/reperfusion (I/R), which may lead to dysregulation of signaling pathways. Ischemic preconditioning (IPC) may prevent dysregulation by preventing UPS dysfunction through inhibition of oxidative damage. OBJECTIVE: Examine the hypothesis that early IPC preserves postischemic UPS function thus facilitating prosurvival signaling events. METHODS AND RESULTS: I/R decreased proteasome chymotryptic activity by 50% in isolated rat heart and an in vivo murine left anterior descending coronary artery occlusion model. Following IPC, proteasome activity was decreased 25% (P<0.05) in isolated heart and not different from baseline in the murine model. Enriched 26S proteasome was prepared and analyzed for protein carbonyl content. Increased (P<0.05) carbonylation in a 53-kDa band following I/R was diminished by IPC. Immunoprecipitation studies indicated that the 53-kDa carbonylation signal was of proteasomal origin. Two-dimensional gel electrophoresis resolved the 53-kDa band into spots analyzed by liquid chromatography/tandem mass spectrometry containing Rpt3/Rpt5 both of which could be immunoprecipitated conjugated to dinitrophenylhydrazine (DNPH). Higher amounts of DNPH-tagged Rpt5 were immunoprecipitated from the I/R samples and less from the IPC samples. I/R increased Bax levels by 63% (P<0.05) which was decreased by IPC. Lactacystin (lac) pretreatment of preconditioned hearts increased Bax by 140% (P<0.05) and also increased ubiquitinated proteins. Pretreatment of hearts with a proteasome inhibitor reversed the effects of IPC on postischemic Rpt5 carbonylation, cardiac function, morphology and morphometry, and ubiquitinated and signaling proteins. CONCLUSIONS: These studies suggest that IPC protects function of the UPS by diminishing oxidative damage to 19S regulatory particle subunits allowing this complex to facilitate degradation of proapoptotic proteins.
Subject(s)
Ischemic Preconditioning, Myocardial , Myocardial Ischemia/physiopathology , Oxidative Stress/physiology , Proteasome Endopeptidase Complex/physiology , Animals , Coronary Occlusion/physiopathology , Heart/physiopathology , Male , Mice , Mice, Inbred Strains , Models, Animal , Rats , Rats, Sprague-Dawley , Ubiquitin/physiology , bcl-2-Associated X Protein/physiologyABSTRACT
Indole-3-carbinol (I3C), derived from cruciferous vegetables, alters estrogen metabolism. Since lupus is estrogen dependent, we reasoned that I3C might be effective in SLE. I3C significantly thwarted disease progression and prolonged survival in (NZBxNZW) F1 mice. Immunofluorescent and serologic analyses in treated animals indicated a transient blockade in B-cell maturation with increased immature B cells, decreased mature B cells, and a significant reduction of certain autoantibodies. Subsequently, a delay in T-cell maturation occurred in the treated group, manifested by significantly increased naive T cells, decreased mature and memory T cells, and decreased CD4:CD8 T-cell ratios. T cells from the I3C cohort, stimulated in vitro with various mitogens, exhibited enhanced responsiveness. Con A-stimulated T cells from I3C-treated mice produced Th1 cytokines, whereas those from control animals produced Th2 cytokines. Our studies suggest immunological mechanisms by which I3C ameliorates SLE in mice and provide a rationale for its use as an adjunctive therapy for human lupus.
Subject(s)
Anticarcinogenic Agents/therapeutic use , B-Lymphocytes/immunology , Indoles/therapeutic use , Lupus Erythematosus, Systemic/drug therapy , Nephritis/drug therapy , T-Lymphocyte Subsets/immunology , Administration, Oral , Animals , Anticarcinogenic Agents/pharmacology , Autoantibodies/drug effects , Autoantibodies/immunology , B-Lymphocytes/drug effects , B-Lymphocytes/metabolism , Cell Differentiation/drug effects , Cell Differentiation/immunology , Cytokines/biosynthesis , Cytokines/drug effects , Cytokines/immunology , Disease Models, Animal , Estrogens/metabolism , Female , Immunoglobulin G/biosynthesis , Immunoglobulin G/drug effects , Immunoglobulin G/immunology , Indoles/pharmacology , Kaplan-Meier Estimate , Longitudinal Studies , Lupus Erythematosus, Systemic/immunology , Lupus Erythematosus, Systemic/mortality , Mice , Nephritis/immunology , Nephritis/mortality , T-Lymphocyte Subsets/drug effects , T-Lymphocyte Subsets/metabolismABSTRACT
Renal biopsy data suggest that renal tubular cells may serve as a reservoir for HIV-1, however the mechanism underlying this finding has not been studied. Here we show that primary human renal proximal tubular epithelial cells (HRPTECs) have the potential to harbor HIV-1 through the DEC-205 receptor. The interaction of HIV-1 with DEC-205 results in the rapid internalization of the virus for lysosomal degradation, without establishing a productive infection. However, a small fraction of incoming virus escapes degradation and can be rescued by T cells. Since pH-modulating agents and an inhibitor of endosomal transport increased HIV-1 accumulation and trans-infection to T cells, it appears that HRPTECs endocytic compartments may be the site of viral persistence and transmission to target cells. The ability of T cells to rescue the virus from HRPTECs further supports the hypothesis that these cells have the potential to serve as a reservoir for HIV-1.
Subject(s)
Epithelial Cells/virology , HIV Infections/transmission , HIV-1/physiology , Kidney Tubules/virology , T-Lymphocytes/virology , Virus Internalization , Antibodies/physiology , Antigens, CD/immunology , Antigens, CD/metabolism , Cells, Cultured , Endocytosis/drug effects , Endocytosis/immunology , Epithelial Cells/immunology , HIV Infections/immunology , HIV Infections/virology , HIV-1/genetics , HIV-1/immunology , Humans , Kidney Tubules/immunology , Kidney Tubules/metabolism , Kidney Tubules/pathology , Lectins, C-Type/immunology , Lectins, C-Type/metabolism , Minor Histocompatibility Antigens , Receptors, Cell Surface/immunology , Receptors, Cell Surface/metabolism , T-Lymphocytes/immunologyABSTRACT
Severe bacterial infections leading to sepsis or septic shock can be induced by bacteria that utilize different factors to drive pathogenicity and/or virulence, leading to disease in the host. One major factor expressed by all clinical isolates of gram-negative bacteria is lipopolysaccharide (LPS); a second factor expressed by some Escherichia coli strains is a K1 polysaccharide capsule. To determine the role of the CD14 LPS receptor in the pathogenic effects of naturally occurring E. coli, the responses of CD14-/- and CD14+/+ mice to three different isolates of E. coli obtained from sepsis patients were compared; two isolates express both smooth LPS and the K1 antigen, while the third isolate expresses only LPS and is negative for K1. An additional K1-positive isolate obtained from a newborn with meningitis and a K1-negative isogenic mutant of this strain were also used for these studies. CD14-/- mice were resistant to the lethal effects of the K1-negative isolates. This resistance was accompanied by significantly lower levels of systemic tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) in these mice than in CD14+/+ mice, enhanced clearance of the bacteria, and significantly fewer additional gross symptoms. In contrast, CD14-/- mice were as sensitive as CD14+/+ mice to the lethal effects of the K1-positive isolates, even though they had significantly lower levels of TNF-alpha and IL-6 than CD14+/+ mice. These studies show that different bacterial isolates can use distinctly different mechanisms to cause disease and suggest that new, nonantibiotic therapeutics need to be directed against multiple targets.
Subject(s)
Antigens, Bacterial/immunology , Bacterial Capsules/immunology , Escherichia coli/immunology , Lipopolysaccharide Receptors/immunology , Polysaccharides, Bacterial/immunology , Animal Structures/microbiology , Animals , Antigens, Bacterial/genetics , Bacterial Capsules/genetics , Colony Count, Microbial , Disease Susceptibility , Escherichia coli/isolation & purification , Escherichia coli Infections/microbiology , Escherichia coli Infections/mortality , Escherichia coli Infections/physiopathology , Gene Deletion , Immunity, Innate/genetics , Interleukin-6/blood , Mice , Mice, Inbred BALB C , Mice, Knockout , Polysaccharides, Bacterial/genetics , Sepsis/microbiology , Survival Analysis , Tumor Necrosis Factor-alpha/bloodABSTRACT
HIV-1 infection of renal cells has been proposed to play a role in HIV-1-associated nephropathy. Renal biopsy data further suggest that renal tubular cells may serve as reservoir for HIV-1. The mechanism by which HIV-1 enters these cells has not been identified. Renal tubular cells do not express any of the known HIV-1 receptors, and our results confirmed lack of the expression of CD4, CCR5, CXCR4, DC-SIGN, or mannose receptors in tubular cells. The aim of this study, therefore, was to determine the mechanism that enables viral entry into renal tubular cells. An in vitro model was used to study the HIV-1 infection of human kidney tubular (HK2) cells and to identify the receptor that enables the virus to enter these cells. Results of these studies demonstrate that the C-type lectin DEC-205 acts as an HIV-1 receptor in HK2 cells. Interaction of HIV-1 with DEC-205 results in the internalization of the virus and establishment of a nonproductive infection. HIV-1-specific strong-stop DNA is detected in the infected HK2 cells for at least 7 d, and the virus can be transmitted in trans to sensitive target cells. HIV-1 entry is blocked by pretreatment with specific anti-DEC-205 antibody. Moreover, expression of DEC-205 in cells that lack the DEC-205 receptors renders them susceptible to HIV-1 infection. These findings suggest that DEC-205 acts as an HIV-1 receptor that mediates internalization of the virus into renal tubular cells, from which the virus can be rescued and disseminated by encountering immune cells.
Subject(s)
AIDS-Associated Nephropathy/virology , Antigens, CD/metabolism , HIV-1/pathogenicity , Kidney Tubules/virology , Lectins, C-Type/metabolism , Receptors, Cell Surface/metabolism , AIDS-Associated Nephropathy/metabolism , Antibodies/physiology , Antigens, CD/immunology , Cell Line , Cells, Cultured , DNA, Viral , HIV-1/genetics , HIV-1/isolation & purification , Humans , Kidney Tubules/metabolism , Kidney Tubules/pathology , Lectins, C-Type/immunology , Minor Histocompatibility Antigens , Receptors, Cell Surface/immunologyABSTRACT
OBJECTIVE: Diarrhea is a common and deadly threat to millions of infants and children. Similarly, malabsorption can aggravate the health status of the chronically sick and especially the elderly. Prompt recovery from intestinal dysfunction may have a substantial impact on many populations. The aim of this study was to test the hypothesis that, in an animal model of cathartic-induce diarrhea, the previously shown proabsorptive effects of gum arabic (GA) could directly reduce and ameliorate intestinal dysfunction. METHODS: Young male rats were offered a standard solid feed and as a sole source of fluid a phenolphthalein-magnesium citrate solution for 3 or 6 days (PC), or the same plus either 10 (GA1) or 20 (GA2) g/L of GA. Other groups had tap water without (CTL) or with 20 g/L GA (CTL + GA), after which the animals were jejunally perfused under anesthesia to test their absorptive capacity. Similarly treated rats were killed and the small intestinal mucosa scraped and processed for nitric oxide synthase (NOS) determination. RESULTS: In 6-day studies addition of GA to the cathartic solution led to increases in net water, sodium and glucose absorption with the higher GA2, relatively to the PC rats. For water (means +/- SEM): PC = 42.4 +/- 3.6; GA2 = 57.9 +/- 3.9 nmol/g.min, p < 0.05. For sodium: PC = 2,139 +/- 334; GA2 = 4,465 +/- 444 nmol/g.min, p < 0.05. After only 3-day exposure, effects were less marked. Total NOS activity was increased in the PC, GA1 and GA2 groups (333 +/- 26; 334 +/- 27; 336 +/- 23 nmol/h.g) compared to CTL (233 +/- 27 nmol/h.g, p < 0.05), while CTL + GA showed a further reduction of activity (190 +/- 18 nmol/h.g, p < 0.05 vs. CTL). CONCLUSIONS: These findings substantiate earlier physiologic and biochemical effects of GA on the gastrointestinal tract, presently conducted in a model of gastrointestinal dysfunction. The data further suggest that a natural proteoglycan such as GA can reduce secretory effects induced by cathartics and, hence, are predictive of potential effectiveness in the context of diarrhea or malabsorption by infectious or functional causes.
Subject(s)
Diarrhea/therapy , Fluid Therapy , Gum Arabic/therapeutic use , Intestinal Absorption/drug effects , Animals , Cathartics/pharmacology , Diarrhea/chemically induced , Dose-Response Relationship, Drug , Gum Arabic/pharmacology , Intestinal Mucosa/drug effects , Intestinal Mucosa/enzymology , Male , Nitric Oxide Synthase/metabolism , Random Allocation , Rats , Rats, Sprague-Dawley , Treatment OutcomeABSTRACT
One of the interesting puzzles of amyloid beta-peptide of Alzheimer's disease (Abeta) is that it appears to polymerize into amyloid fibrils in a parallel beta sheet topology, while smaller subsets of the peptide produce anti-parallel beta sheets. In order to target potential weak points of amyloid fibrils in a rational drug design effort, it would be helpful to understand the forces that drive this change. We have designed two peptides CHQKLVFFAEDYNGKDEAFFVLKQHW and CHQKLVFFAEDYNGKHQKLVFFAEDW that join the significant amyloidogenic Abeta (14-23) sequence HQKLVFFAED in parallel and anti-parallel topologies, respectively. (Here, the word "parallel" refers only to residue sequence and not backbone topology). The N-termini of the hairpins were labeled with the fluorescent dye 5-((((2-iodoacetyl)amino)ethyl)amino)naphthalene-1-sulfonic acid (IAEDANS), forming a fluorescence energy transfer donor-acceptor pair with the C-terminus tryptophan. Circular dichroism results show that the anti-parallel hairpin adopts a beta-sheet conformation, while the parallel hairpin is disordered. Fluorescent Resonance Energy Transfer (FRET) results show that the distance between the donor and the acceptor is significantly shorter in the anti-parallel topology than in the parallel topology. The fluorescence intensity of anti-parallel hairpin also displays a linear concentration dependence, indicating that the FRET observed in the anti-parallel hairpin is from intra-molecular interactions. The results thus provide a quantitative estimate of the relative topological propensities of amyloidogenic peptides. Our FRET and CD results show that beta sheets involving the essential Abeta (14-23) fragment, strongly prefer the anti-parallel topology. Moreover, we provide a quantitative estimate of the relative preference for these two topologies. Such analysis can be repeated for larger subsets of Abeta to determine quantitatively the relative degree of preference for parallel/anti-parallel topologies in given fragments of Abeta.
Subject(s)
Amyloid beta-Peptides/chemistry , Amyloid/chemistry , Drug Design , Peptides/chemistry , Protein Structure, Secondary , Amino Acid Sequence , Fluorescence Resonance Energy Transfer , Molecular Sequence Data , Protein ConformationABSTRACT
A 71-year-old woman who presented with left abdominal pain was found to have a noncalcified renal mass with a perisplenic extension on imaging studies. Histologically, the tumor showed predominantly malignant spindle cells with extensive osteoid and chondroid matrix production. Various growth patterns resembling rhabdomyosarcoma, malignant fibrous histiocytoma, and fibrosarcoma were also observed. Immunohistochemistry showed positive staining of the neoplastic cells for cytokeratin and focally positive staining for CD10 and CD117 (c-Kit). Electron microscopic examination revealed a poorly differentiated neoplasm with both mesenchymal and epithelial features. The tumor was diagnosed as a sarcomatoid renal cell carcinoma with overgrowth of the sarcomatoid component (World Health Organization: renal cell carcinoma, unclassified). To our knowledge, sarcomatoid renal cell carcinoma with such a broad morphologic phenotype in a single case has not been documented. Furthermore, the CD117 expression in a sarcomatoid renal cell carcinoma that was observed in this case merits further investigation.
Subject(s)
Carcinoma, Renal Cell/pathology , Carcinosarcoma/pathology , Kidney Neoplasms/pathology , Aged , Biomarkers, Tumor/analysis , Carcinoma, Renal Cell/chemistry , Carcinoma, Renal Cell/surgery , Female , Humans , Kidney Neoplasms/chemistry , Kidney Neoplasms/surgery , Nephrectomy , Proto-Oncogene Proteins c-kit/analysis , Splenectomy , Treatment OutcomeABSTRACT
Cellular senescence may be accompanied by accumulation of large aggregates of oxidized proteins, also known as lipofuscin. The hypothesis that cellular accumulation of lipofuscin-like materials (LIP) results in cell death as a result of proteasome inhibition was examined. Rat neonatal cardiomyocytes were incubated with synthetic LIP for up to 48 h. This was accompanied by increases in cellular autofluorescence (207% by 48 h; p < 0.05) and electron microscopic evidence of internalization of LIP particles. LIP incubation resulted in loss of viability (-46% by 48 h; p < 0.05) through apoptotic cell death. Although 20S-proteasome activity was increased by 74% after 6 h, both 20S- and 26S-proteasome activities were decreased after 48 h of incubation (-54% (p < 0.05) and -50%, respectively), accompanied by large increases in ubiquitinated proteins. Several proteasome-regulated proapoptotic proteins, including c-Jun (2.9-fold; p < 0.05), Bax (1.8-fold; p < 0.05), and p27(kip1) (3.2-fold; p < 0.05), were observed to be increased by 48 h. Observation of ubiquitinated homologues of Bax and p27(kip1) suggested that part of the increase was due to decreased proteasomal degradation of these proteins. The results of this study are consistent with the conclusion that accumulation of LIP results in inhibition of the proteasome, which initiates an apoptotic cascade as a result of dysregulation of several proapoptotic proteins.
Subject(s)
Apoptosis/physiology , Lipofuscin/physiology , Proteasome Inhibitors , Adenosine Triphosphate/metabolism , Animals , Female , Free Radicals , Lipofuscin/metabolism , Microscopy, Electron , Myocardium/cytology , Myocardium/metabolism , Oxidation-Reduction , Rats , Rats, Sprague-Dawley , Ubiquitin/metabolismABSTRACT
This study assesses the vulnerability of fetal guinea pig heart to metabolic changes during acute nonlethal in utero hypoxia. Guinea pigs (50-55 days gestation) were exposed to 7% O2 for 2 h and room air for 4 h. Fetal hearts were harvested before hypoxia, at the end of hypoxia, and 4 h after hypoxia, and analyzed for: apoptosis (TUNEL), histology, lipid peroxidation and ATP. A group of posthypoxic dams was taken to gestation. Within 48 h postpartum, the function of neonatal hearts was tested and cerebral histology examined. Fetal heart ATP was decreased by 27% at the end of hypoxia and by 32% 4 h after hypoxia. The lipid peroxides, 4-hydroxynonenal and malondialdehyde, were decreased by 37 and 46%, respectively, by 4 h after hypoxia. The apoptotic index increased from 2% in prehypoxic hearts to 8.4% by 4 h after hypoxia. Fetal heart morphology was unremarkable. Postpartum neonatal cardiac function was not affected and cerebral histology was unremarkable. These results support the conclusion that nonlethal in utero hypoxia has acute effects on the fetal heart but no persistent cardiac or cerebral effects in the postpartum neonate.
Subject(s)
Animals, Newborn/physiology , Brain/anatomy & histology , Heart/embryology , Heart/physiology , Hypoxia/complications , Pregnancy Complications , Adenosine Triphosphate/analysis , Aldehydes/analysis , Animals , Apoptosis , Female , Gestational Age , Guinea Pigs , In Situ Nick-End Labeling , Lipid Peroxidation , Malondialdehyde/analysis , Myocardium/chemistry , Oxygen/administration & dosage , Pregnancy , Prenatal Exposure Delayed EffectsABSTRACT
Dietary modulation has the potential to prevent or ameliorate systemic lupus erythematosus (SLE). Indole-3-carbinol (I3C), which is abundant in cruciferous vegetables, was evaluated in a murine model of SLE because of its antiestrogenic activities. Female (NZB x NZW) F1 mice, which develop SLE, were fed an AIN76A diet without or with 0.2 g/kg I3C, starting soon after weaning or at 5 mo of age. At 12 mo of age, 80% of mice fed the I3C-supplemented diet soon after weaning were alive compared with only 10% of controls. When experimental diets were initiated at 5 mo of age, 100% of I3C fed mice and 30% of controls were alive at 12 mo of age. Anti-double-stranded DNA (dsDNA) antibodies developed in all groups, although at several time points, the levels produced in I3C-fed mice were significantly lower. Renal disease (proteinuria, histologic changes, IgG immune complex deposition, subepithelial deposits and diffuse epithelial cell foot process effacement) was more severe in controls with both protocols. The estrogen urinary metabolite ratio of 2- to 16alpha-hydroxyestrone was increased in I3C-fed mice. These findings demonstrate a profound effect of dietary I3C in experimental SLE.
Subject(s)
Antioxidants/pharmacology , Dietary Supplements , Indoles/pharmacology , Oxidative Stress/drug effects , Animals , Disease Models, Animal , Kidney/drug effects , Kidney/pathology , Kidney/ultrastructure , Kidney Diseases/prevention & control , Life Expectancy , Mice , Mice, Inbred Strains , Time FactorsABSTRACT
Muscle atrophy and wasting is a serious problem that occurs in patients with prolonged debilitating illness, burn injury, spinal injury, as well as with space flight. Current treatment for such atrophy, which often relies on nutritional supplementation and physical therapy, is of limited value in preventing the muscle wasting that occurs. Considerable recent attention has focused on the use of anabolic growth factors such as insulin-like growth factor (IGF-1) in preventing muscle atrophy during limb disuse or with various catabolic conditions. However, potential side effects such as hypoglycemia appear to be limiting factors in the usefulness of IGF-1 for clinical treatment of muscle wasting conditions. The formulation of IGF-1 used in this study (IGF-1/BP3) is already bound to its endogenous-binding protein (BP3) and, as a result, has a greater specificity of action and significantly less hypoglycemic effect. Using a rat model of hind limb suspension (HLS) for 10 days, we induced marked muscle atrophy that was accompanied by enhanced muscle proteolysis and reduced muscle protein content. When HLS rats were treated with IGF-1/BP3 (50 mg/kg, b.i.d.), they retained greater body and muscle mass. Muscle protein degradation was significantly reduced and muscle protein content was preserved. The rate of protein synthesis, although somewhat reduced in HLS muscle, was not significantly elevated by IGF-1/BP3 treatment. Volume density of HLS-treated muscles were increased compared to untreated HLS rats and the actual number of fibers per area of muscle was likewise increased. The results of the current study suggest that IGF-1/BP3 might be useful for inhibiting muscle proteolysis in catabolic conditions and thus preserving muscle protein content and mass.
Subject(s)
Insulin-Like Growth Factor Binding Protein 3/pharmacology , Insulin-Like Growth Factor I/pharmacology , Muscle Proteins/drug effects , Muscular Atrophy/drug therapy , Animals , Hindlimb Suspension , Male , Models, Animal , Muscle Proteins/analysis , Muscle, Skeletal/drug effects , Muscle, Skeletal/pathology , Rats , Rats, WistarABSTRACT
This study was prompted by the recent revision of the definition of bronchioloalveolar carcinoma (BAC) that defines BAC, light microscopically, as a non-invasive carcinoma. Doubt has been raised whether BACs retain certain specific microscopic features after becoming invasive or metastatic. We studied 7 cases of metastatic, non-mucinous BAC by electron microscopy. Of these cases, 5 showed Clara cell granules and 1 revealed lamellar bodies. The remaining case did not show ultrastructural features of BAC. These findings suggest that most BACs retain some of their ultrastructural features after becoming metastatic neoplasms.
Subject(s)
Adenocarcinoma, Bronchiolo-Alveolar/ultrastructure , Laminin/analysis , Lung Neoplasms/ultrastructure , Proteins/analysis , Uteroglobin , Adenocarcinoma, Bronchiolo-Alveolar/chemistry , Adenocarcinoma, Bronchiolo-Alveolar/secondary , Adult , Aged , Cytoplasm/ultrastructure , Female , Humans , Immunohistochemistry , Lung Neoplasms/chemistry , Lung Neoplasms/pathology , Male , Microscopy, Electron , Middle AgedABSTRACT
Malignant rhabdoid tumor of the kidney is an uncommon renal tumor in children. The tumor has aggressive behavior and a poor prognosis and is extremely rare in adults; only 3 cases of renal rhabdoid tumors have been reported in adults. We describe here the microscopic, immunohistochemical, and electron microscopic characteristics of another case in a 38-year-old woman. This case reinforces the importance of recognizing this entity in the adult population.
Subject(s)
Kidney Neoplasms/pathology , Rhabdoid Tumor/pathology , Adult , Fatal Outcome , Female , Humans , Immunohistochemistry , Kidney Neoplasms/metabolism , Kidney Neoplasms/ultrastructure , Microscopy, Electron , Mucin-1/analysis , Phosphopyruvate Hydratase/analysis , Rhabdoid Tumor/metabolism , Rhabdoid Tumor/ultrastructure , S100 Proteins/analysis , Vimentin/analysisABSTRACT
Previous experiments have shown that a soluble fiber, gum arabic (GA), enhances water, electrolyte, and glucose absorption in animal models of diarrhea. The mechanisms implicated in this effect have not been fully elucidated. This study examined the possibility that paracellular transport is modulated by luminal GA, resulting in an enhanced rate of absorption in the small intestine. This hypothesis was tested by 3-hr jejunal perfusions on anesthetized rats with solutions containing 140 mM NaCl, 5 mM KCl, and 2 microCi/liter (74 kBq) 3H2O, with either 2.5 g/liter GA [+GA] or in its absence [CTL], and one of the following agents, capable of altering paracellular transport: chenodeoxycholic acid at 0.5 mM (CDC), 2,4,6-triaminopyrimidine (TAP) at 20 mM, and protamine at 100 mg/liter (PTM). Sodium, potassium, net water, and unidirectional water movement were measured. The addition of GA increased sodium absorption in perfusions with CDC, TAP, or PTM only. Similar effects by GA on net water absorption rates were obtained in tissues permeabilized with CDC and PTM; however, GA added to TAP did not normalize the reduction caused by TAP. Although PTM did not alter net water absorption, addition of GA to perfusates with PTM enhanced absorption values above those of CTL. GA reversed the strong negative effects of CDC on potassium absorption but was ineffective in this regard with TAP and PTM. The data obtained with those reagents that affect paracellular transport and the histological evidence support the view that GA promotes net absorption by this route in the small intestine of normal rats.
Subject(s)
Gum Arabic/pharmacology , Intestinal Absorption/drug effects , Water-Electrolyte Balance/drug effects , Animals , Cell Membrane Permeability/drug effects , Cell Membrane Permeability/physiology , Chenodeoxycholic Acid/pharmacology , Intestinal Absorption/physiology , Jejunum/drug effects , Jejunum/physiology , Male , Perfusion , Potassium/metabolism , Protamines/pharmacology , Pyrimidines/pharmacology , Rats , Sodium/metabolism , Water-Electrolyte Balance/physiologyABSTRACT
We report the case of a 74-year-old white man with a mass in the head of the pancreas, which was found incidentally on computerized tomographic scan during a workup for deep vein thrombosis. Endoscopy with pancreatic duct brushings yielded a diagnosis of adenocarcinoma. A pancreaticoduodenectomy followed, with complete resection of the tumor. Pathologic examination showed 2 distinct components. One component was a conventional infiltrating pancreatic ductal adenocarcinoma, and the other component was high-grade sarcoma with features of malignant fibrous histiocytoma. To our knowledge, this carcinosarcoma is the seventh reported case of a primary pancreatic neoplasm with mixed carcinomatous and sarcomatous elements.