A differential interaction of daunomycin,adriamycin and their derivatives with human erythrocytes and phospholipid bilayers

Drug-membrane association of daunomycin, adriamycin and three of its derivatives, adriamycin-14-octanoate (AD-14-OCTA), adriamycin-14-acetate (AD-14-ACE) and $\text{N-}\text{trifluoroacetyladriamycin-14-valerate}$ (AD32), was studied using phospholipid bilayers and human erythrocytes. The various drugs exhibited a differential affinity to membrane-lipid domains.Lipid-incorporated drugs exhibit a marked change in the shape of the emission spectrum which was utilized for the evaluation of the apparent dielectric constant, ?, of the environment surrounding the anthracycline moiety, as well as for the determination of the partitioning constant. By measuring the fluorescence polarization and the fluorescence lifetime of the incorporated drugs, rotational relaxation times of 4–8 ns were derived. These parameters provide a supportive evidence for the association of the fluorophore of the drugs with membrane-lipid domains.The anthracycline derivatives interact to a different degree with dipalmitoyl phosphatidylcholine and phosphatidylserine as reflected by changes in their thermotropic properties assessed by differential scanning calorimetry. Daunomycin was the most effective in decreasing the temperature of the phase transition and brought about a comparable reduction in the enthalpy of melting as AD32 and AD-14-OCTA. Adriamycin was the least potent of the series.AD-14-ACE and AD32 protected erythrocytes against hypotonic lysis, adriamycin and daunomycin had no significant effect on the susceptibility to hypotonic lysis, whereas AD-14-OCTA proved to be hemolytic even at low concentration (approx. 10^?7 M).The interaction of erythrocytes with daunomycin, AD-14-ACE and Ad-14-OCTA resulted in a shape change from biconcave discs to cups. Adriamycin and AD32 did not affect erythrocyte shape.The differential drug-membrane interactions may be an important determinant in the antitumor differential efficiency of the drugs, especially in view of the fact that derivatives that do not intercalate into the DNA (AD32) are at least as potent as those that do.     

Osteoarthrosis in guinea pigs: histopathologic and scanning electron microscopic features

Spontaneous cartilage degeneration of the femorotibial joint of male Hartley guinea pigs, 61 to 365 days old, was studied by light microscopy (LM) and scanning electron microscopy (SEM) to determine the incidence, age at onset, and to characterize the early changes. Knee joints of 61 day old animals were histologically and ultrastructurally normal. Focal minimal degeneration characterized by cell and proteoglycan loss with surface fibrillation was first observed by LM on the medial tibial plateau (MTP) in two of five 89 day old animals. Mild lesions characterized by focal surface disruption, primarily in the area of medial tibial plateau not covered by the meniscus, were observed in three of five 89 day old animals by SEM. Light microscopic alterations in knee joints of 4, 5, and 6 month old animals consisted of varying degrees of focal chondrocyte death, decreased toluidine blue matrix staining, and surface fibrillation. Small chondrocytic clones were first observed in medial tibial cartilage of 6 month old animals with moderate focal degeneration. Ultrastructurally, 4, 5, and 6 month old animals generally had moderate to severe fibrillation involving primarily the area of the medial tibial plateau not covered by the meniscus. Tibial osteophyte formation, mild synovial hyperplasia, medial femoral and meniscal cartilage degeneration, were first seen by LM in 9 month old animals. Lesions in 1 year old animals were similar, but more severe and included subchondral sclerosis of medial tibial and femoral bone. Bilateral fibrillation of greater than 50% of the medial tibial articular surface was observed in all 1 year old animals by SEM.(ABSTRACT TRUNCATED AT 250 WORDS)     

Use of a biotinylated probe and in situ hybridization for light and electron microscopic localization of Po mRNA in myelin-forming Schwann cells

A biotinylated Po glycoprotein cDNA was hybridized in situ to aldehyde-fixed vibratome sections and to aldehyde-fixed thin sections of Lowicryl-embedded trigeminal ganglia of 15 day old rats. Alkaline phosphatase and peroxidase detectors were used for light microscopic (LM) studies and peroxidase or colloidal gold were employed for electron microscopic (EM) detection. In both LM and EM sections, probe was found in cytoplasmic areas of myelin-forming Schwann cells that were enriched in granular endoplasmic reticulum, demonstrating that these regions contain Po mRNA. Interestingly, Po mRNA tended to cluster in regions close to the developing myelin sheath. Relatively simple methods are here described for EM detection of mRNA with reasonable tissue preservation and high resolution. These methods may be useful for developmental and disease-related studies of specific mRNAs in mammalian tissues.     

Staining of paraganglionic cells with lead hematoxylin

Lead hematoxylin staining in most paraganglionic cells is too faint to be observed in the light microscope (LM). Paraganglionic cells which appear stained (LM) are also known to contain more and larger specific granules (as seen in the electron microscope, EM) than those paraganglionic cells remaining unstained (LM). However, also specific granules in lead hematoxylin-negative paraganglionic cells (LM) bind lead ions (EM), which behaviour is the basis of lead hematoxylin staining. It is concluded that lead hematoxylin stains matrix material of specific granules but the amount of granule material mostly is too small to yield colour intensities to be observed in the LM.     

Benzidine dihydrochloride as a chromogen for single- and double-label light and electron microscopic immunocytochemical studies

Although very sensitive chromogens have been adapted for localization of horseradish peroxidase in anterograde and retrograde tracing studies, they have not been successfully applied in immunocytochemical studies. This report describes a protocol which uses benzidine dihydrochloride (BDHC) as the chromogen for light (LM) and electron microscopic (EM) immunocytochemical studies. The protocol is comparable to that used for tetramethylbenzidine, except that the pH of the reaction is above 6.0. At the LM level, the BDHC reaction product is bluish-green and crystalline. Both the color and form of the product are readily distinguished from the reddish-brown DAB reaction product. LM double-labeling studies are therefore feasible. The use of BDHC also increases significantly the sensitivity of the immunoreaction. Higher fixative concentrations can be used, less detergent is necessary, and higher primary antibody dilutions are possible. By osmicating at 45 degrees C in an s-collidine buffer it is possible to preserve the soluble BDHC reaction product for EM analysis. Immunoreactive cells are particularly well labeled with this new protocol. The BDHC crystals are easily detected at the EM level and can be distinguished from flocculent DAB reaction product. This feature makes EM double-labeling studies possible.     

Interaction of Adriamycin and N-Trifluoroacetyladriamycin-14-Valerate with Cardiolipin-Containing Lipid Bilayers

Abstract

The interaction of adriamycin (ADR) and N-Trifluoroacetyladriamycin-14-valerate (AD 32) with cardiolipin (CL)-containing multilamellar vesicles was studied by high-sensitivity differential scanning calorimetry, using liposomes formed from either dipalmitoylphosphatidylcholine (DPPC) or dipalmitoylphosphatidylglycerol (DPPG) containing small amounts of CL. the drugs partitioned into cardiolipin-containing neutral and acidic bilayers in a manner similar to that observed earlier with CL-free bilayers. the partition coefficient of adriamycin in bilayers of vesicles prepared from DPPG or DPPG in admixture with CL was much higher than that obtained with neutral DPPC vesicles or the DPPC together with CL. Under all conditions, AD 32 was essentially completely partitioned into the lipid phase of the investigated phospholipid membranes. As expected, addition of adriamycin to CL-containing vesicles did not significantly change the thermotropic behavior of these bilayers, whereas the fluidizing effect of AD 32 was directly related to the CL content of the vesicles. the multipeak transitions produced by the anthracyclines in pure DPPG bilayers were preserved in the presence of CL, but the endotherms were broader and slightly shifted to lower temperatures, a finding indicative of stronger interactions. Chlorpromazine (CPZ), which was used as a reference compound to compare the effects produced by the anthracyclines, was found to behave similarly to AD 32 and to be more effective than quinidine (QND), in agreement with their behavior in CL-free liposomes.     

Detection of fragmented DNA in apoptotic cells embedded in LR white: A combined histochemical (LM) and ultrastructural (EM) study.

We developed an improved method for the detection of double-strand DNA breaks in apoptotic cells at both the light (LM) and electron microscopic (EM) levels using a modification of the TdT (terminal deoxynucleotidyl transferase)-mediated dUTP nick end-labeling (TUNEL) technique. Cultured rat cerebellar granule cells were exposed to low potassium conditions to induce apoptosis. Twenty-four hr after treatment, one group of cells was fixed in situ with 4% paraformaldehyde and labeled for DNA fragmentation characteristic of apoptosis. Apoptotic cells were visualized with diaminobenzidine (DAB) and viewed by LM. The second group of cells was detached from the culture dish, pelleted, fixed with a 4% paraformaldehyde and 0. 2% glutaraldehyde mixture, and embedded in LR White. For LM, the modified TUNEL technique was performed on 1.5-microm LR White sections and apoptotic cells were visualized using an enzymatic reaction to generate a blue precipitate. For EM, thin sections (94 nm) were processed and DNA fragmentation was identified using modified TUNEL with streptavidin-conjugated gold in conjunction with in-depth ultrastructural detail. Alternate sections of cells embedded in LR White can therefore be used for LM and EM TUNEL-based detection of apoptosis. The present findings suggest that the modified TUNEL technique on LR White semithin and consecutive thin sections has useful application for studying the fundamental mechanism of cell death. (J Histochem Cytochem 47:561-568, 1999)     

Use of a biotinylated probe and in situ hybridization for light and electron microscopic localization of P 0 mRNA in myelin-forming Schwann cells

Summary A biotinylated P ₀ glycoprotein cDNA was hybridized in situ to aldehyde-fixed vibratome sections and to aldehyde-fixed thin sections of Lowicryl-embedded trigeminal ganglia of 15 day old rats. Alkaline phosphatase and peroxidase detectors were used for light microscopic (LM) studies and peroxidase or colloidal gold were employed for electron microscopic (EM) detection. In both LM and EM sections, probe was found in cytoplasmic areas of myelinforming Schwann cells that were enriched in granular endoplasmic reticulum, demonstrating that these regions contain P ₀ mRNA. Interestingly, P ₀ mRNA tended to cluster in regions close to the developing myelin sheath. Relatively simple methods are here described for EM detection of mRNA with reasonable tissue preservation and high resolution. These methods may be useful for developmental and disease-related studies of specific mRNAs in mammalian tissues.     

Immunocytochemical localization of cathepsins B and H in rat liver

Summary Light and electron microscopic localization of cathepsins B and H in rat liver was investigated by immunoenzyme and protein A-gold techniques. For light microscopy (LM), semi-thin sections of the Epon-embedded material were stained by the immunoenzyme technique after removal of epoxy resin. For electron microscopy (EM), ultrathin sections of the Lowicryl K4M-embedded material were stained by the protein A-gold technique. By LM, reaction deposits for cathepsins B and H were present in the cytoplasmic granules of parenchymal cells and endothelial cells, and Kupffer cells. The sinus-lining cells and the parenchymal cells showed the similar staining intensity. By EM, gold particles were present exclusively in lysosomes of all the cell types cited above. The same results were obtained from quantitative analysis. In addition, Golgi complexes themselves were mostly negative but some small vesicles on the trans side of them were labeled for these proteinases. The results indicate that cathepsins B and H are present in the lysosomes of rat liver and that these enzymes seem to be transported by small vesicles from endoplasmic reticulum to lysosomes via tubuloreticular network of the trans Golgi region.     

Immunocytochemical localization of cathepsins B and H in rat liver

Light and electron microscopic localization of cathepsins B and H in rat liver was investigated by immunoenzyme and protein A-gold techniques. For light microscopy (LM), semi-thin sections of the Epon-embedded material were stained by the immunoenzyme technique after removal of epoxy resin. For electron microscopy (EM), ultra-thin sections of the Lowicryl K4M-embedded material were stained by the protein A-gold technique. By LM, reaction deposits for cathepsins B and H were present in the cytoplasmic granules of parenchymal cells and endothelial cells, and Kupffer cells. The sinus-lining cells and the parenchymal cells showed the similar staining intensity. By EM, gold particles were present exclusively in lysosomes of all the cell types cited above. The same results were obtained from quantitative analysis. In addition, Golgi complexes themselves were mostly negative but some small vesicles on the trans side of them were labeled for these proteinases. The results indicate that cathepsins B and H are present in the lysosomes of rat liver and that these enzymes seem to be transported by small vesicles from endoplasmic reticulum to lysosomes via tubuloreticular network of the trans Golgi region.     

Comparison of the binding of anthracycline derivatives to purified DNA and to cell nuclei

Fluorescence method was used to study the interactions of anthracyclines with purified DNA and with cell nuclei at 37 degrees C, at pH ranging from 6.8 to 8. Four anthracyclines were used; adriamycin (ADR), 4'-o-tetrahydropyranyladriamycin (THP-ADR), daunorubicin (DNR) and aclacinomycin (ACM). The values of pKa of deprotonation of these four drugs in the pH range 6.5-8.5 are 8.4, 7.7, 8.4 and 7.0 for ADR, THP-ADR, DNR and ACM, respectively. The overall binding constants K* of these four drugs to purified DNA was determined at various pH values. The binding constants K0 and K+ of the respectively neutral form and once protonated form of the drugs to DNA were calculated. Using cell nuclei from K562 cells, the amount of drug intercalated (CN) within the nuclei of K562 cells and the amount of free drug (CE) in the solution were determined at various pH values: measuring at the same pH values, a linear correlation occurred between K* and CN/CE.     

Kainic acid lesioning of the preoptic area alters positive feedback of estrogen in prepubertal female rats

Stereotaxic infusion of kainic acid (KA) was performed to induce intrinsic neural lesions of the preoptic area (POA) in 25-day-old female rats. After KA infusion, rats in Experiment 1 received 10 micrograms of estradiol benzoate (EB) administered subcutaneously to assess positive feedback of EB on release of luteinizing hormone (LH) from the pituitary gland. Rats were perfused for light microscopic (LM) or electron microscopic (EM) evaluation of the lesion site. Rats of Experiment 2 were allowed to develop until the appearance of vaginal opening (VO) after which time vaginal lavages were taken to monitor the cyclicity of the vaginal epithelium. At 50 days of age, the right ovary from each rat was removed, trimmed of fat, and weighed. At 60 days of age, the remaining ovary was removed to assess compensatory ovarian hypertrophy (COH). In Experiment 3, we investigated the effects of POA/KA-infusion on sexual behavior. Sex behavior tests were conducted at 48 h after EB during the dark phase of the light cycle. In Experiment 1, all the control and saline-infused rats exhibited the expected rise of plasma LH two days after estrogen injection while the POA/KA-infusion abolished the positive feedback effect of EB on LH release. Ultrastructural examination of the lesion site revealed that neurons were undergoing acute degeneration while axons and afferent terminals seen in the same fields of analysis were morphologically intact. Preoptic area/KA lesions caused a marked delay in the appearance of VO. Duration of this temporal delay in POA/KA-lesioned rats was approximately 4 days, or one vaginal cycle. The lesioned animals showed normal compensatory hypertrophy after unilateral ovariectomy.(ABSTRACT TRUNCATED AT 250 WORDS)     

A scanning calorimetric study of the interaction of anthracyclines with neutral and acidic phospholipids alone and in binary mixtures

High sensitivity differential scanning calorimetry was employed to study the thermotropic behavior of multilamellar vesicles of neutral and acidic phospholipids and binary mixtures thereof in the presence of anthracycline antibiotics. Adriamycin and its lipophilic analogue, N-trifluoroacetyladriamycin-14-valerate (AD32) were investigated and compared to chlorpromazine and quinidine with respect to their ability to affect the pretransition and the main transition of the phospholipids suspended in physiological buffer. With liposomes of neutral dipalmitoylphosphatidylcholine the observed effects paralleled to some extent the corresponding octanol/buffer partition coefficients, with adriamycin being the least effective. Calorimetric measurements on liposomes prepared from pure dipalmitoylphosphatidylglycerol or from binary mixtures of dipalmitoylphosphatidylglycerol and dipalmitoylphosphatidylcholine showed that modulation of bilayer properties by adriamycin was greatly enhanced in the presence of negatively charged lipid headgroups presumably as a result of electrostatic interactions. AD32 interacted differently from adriamycin with the acidic bilayers at low drug concentrations, in a manner similar to that of its interaction with neutral bilayers. At high drug concentrations both adriamycin and AD32 produced transitions with multiple peaks not exhibited by chlorpromazine and quinidine which may be the result of a specific association of the anthracyclines with dipalmitoylphosphatidylglycerol. All four drugs produced only minor changes in the enthalpy of the main transition of the investigated lipids. The present findings are discussed in terms of their possible physiological relevance.     

Structural and functional modifications of sertoli cells in the testis of adult follicle-stimulating hormone receptor knockout mice

Follicle stimulating hormone (FSH) plays important roles during testicular development and in the maintenance of spermatogenesis in the adult. However, the cellular events or pathways that FSH regulates to achieve these effects in Sertoli cells, where the FSH receptors (FSH-R) are located, is still not fully elucidated. The development of FSH-R knockout (FORKO) mice provides a model to examine alterations in testicular structure and function in its absence. To this end, light (LM) and electron microscopic (EM) analyses of perfusion-fixed testes of wild-type and FORKO mice of different ages were performed. Under the LM, a significant reduction was noted in the profile area of seminiferous tubules of FORKO mice compared with their wild-type counterparts at different ages. In addition, FORKO testes revealed large irregularly shaped spaces within the seminiferous epithelium, extending from the base to the lumen. Such spaces were often separated by anastomotic cords of spherical germ cells or completely surrounded elongating spermatids. This phenotype was restricted to half or less of the circumference of only some tubules, but was seen at all stages. EM analyses revealed that the spaces corresponded to an apparent accumulation of fluid in the Sertoli cell cytoplasm, coincident with an absence of the fine flocculent ground substance seen in wild-type mice. However, the Sertoli organelles, while less prominent, appeared intact and to be floating in the enlarged fluid-filled cytoplasm. Functionally, androgen-binding protein (ABP), a major secretory protein of Sertoli cells, was dramatically reduced in FORKO mice. These results suggest that FSH-R signaling normally maintains water balance in Sertoli cells in addition to regulating ABP production.     

The atrial proliferative response following partial ventricular amputation in the heart of the adult newt. A light and electron microscopic autoradiographic study

This investigation characterizes the atrial proliferative response following partial ventricular amputation in adult newts. Newts processed for light microscopic autoradiography were given either a single injection (SI) of ³H-thymidine 1 hr before fixation and killed at intervals up to 25 days after ventricular wounding or were given six injections (MU), one every 12 hr, and fixed at intervals up to 21 days. Atria processed for EM autoradiography (EMA) were removed 1 hr after injection and 15 days after wounding. Mitotic (MI) and thymidine-labeling indices (TI) were calculated for the epicardium, subepicardial CT and myocardium of both atria. Sham-operated and unoperated animals served as controls. There was no localization of labeled or mitotic cells within the atria of SI or MU animals (P > 0.16) for any cell type. MI and TI for the epicardial and CT cells did not differ from sham-operated controls (P > 0.35). A maximum TI of 6.4% and MI of 0.4% was observed in the atrial myocardium of SI animals on day 15. A maximum TI of 13.8 and 5.9% was observed for the left and right atrial myocardium, respectively, of MI animals on day 12. EMA confirmed that atrial myocytes were engaging in mitosis and DNA synthesis.     

Lobular and cellular patterns of early hepatic glycogen deposition in the rat as observed by light and electron microscopic radioautography after injection of 3H-galactose

Very low hepatic glycogen levels are achieved by overnight fasting of adrenalectomized (ADX) rats. Subsequent injection of dexamethasone (DEX), a synthetic glucocorticoid, stimulates marked increases in glycogen synthesis. Using this system and injecting 3H-galactose as a glycogen precursor 1 hr prior to sacrifice, the intralobular and intracellular patterns of labeled glycogen deposition were studied by light (LM) and electron (EM) microscopic radioautography. LM radioautography revealed that 1 hr after DEX treatment, labeling patterns for both periportal and centrilobular hepatocytes resembled those in rats with no DEX treatment: 18% of the hepatocytes were unlabeled, and 82% showed light labeling. Two hours after treatment with DEX, 14% of the hepatocytes remained unlabeled, and 78% were lightly labeled; however, 8% of the cells, located randomly throughout the lobule, were intensely labeled. An increased number of heavily labeled cells (26%) appeared 3 hr after DEX treatment; and by 5 hr 91% of the hepatocytes were intensely labeled. Label over the periportal cells at this time was aggregated, whereas centrilobular cells displayed dispersed label. EM radioautographs showed that 2 to 3 hr after DEX injection initial labeling of hepatocytes, regardless of their intralobular location, occurred over foci of smooth endoplasmic reticulum (SER) and small electron-dense particles of presumptive glycogen, and in areas of SER and distinct glycogen particles. After 5 hrs of treatment with DEX, the intracellular distribution of label reflected the glycogen patterns characteristic of periportal or centrilobular regions.     

Localization of the nerve growth factor receptor on fetal human schwann cells in culture

Previous studies have established that Schwann cells (SC) in culture express an NGF receptor. In this study, cultures of fetal human SC were established from fetal nerves and various light microscopic (LM) and electron microscopic (EM) techniques were used to localize the NGF receptor on the SC. Results indicate that NGF receptor is localized to the plasma membrane of the SC. Quantitative digital analysis determined that the distal portion of the SC process had high concentrations of NGF receptor. The possible functional significance of this latter observation is discussed in terms of SC migration and ensheathment of axons.     

Filtration and agar embedding applied to fine needle aspirates for tumor diagnosis by electron microscopy. A combined technique.

OBJECTIVE: To develop a novel method for processing of fine needle aspirates subjected to electron microscopic (EM) study. STUDY DESIGN: Included 70 cases of poorly differentiated malignant tumors in which a definitive diagnosis was not possible on light microscopic (LM) examination and that thus required application of an ancillary technique such as FNA/EM, for diagnosis. We have established a novel method of processing, a technique of filtration through nylon mesh filters to eliminate red blood cells (RBCs) and necrotic debris, followed by agar well embedding to avoid loss of diagnostic material during processing without centrifugation at later steps after agar embedding, thus minimizing the time required for processing. It was successfully carried out in 70 cases. RESULTS: The combined technique was extremely effective in eliminating RBCs and necrotic debris. It also avoided further loss of valuable diagnostic material. An accurate diagnosis was rendered in 70 cases; that was not possible by LM alone. The whole procedure saves two to three hours of processing as centrifugation is not required after the agar embedding step. CONCLUSION: This technique was found to be cost- and time-effective, particularly suitable for developing countries, where financial resources are limited.     

Localization of cathepsin L in rat kidney revealed by immunoenzyme and immunogold techniques

Localization of cathepsin L in rat kidney was investigated by immunocytochemical techniques. Kidneys were fixed by perfusion and embedded in Epon or Lowicryl K4M without postosmication. For light microscopy (LM), semi-thin sections of the Epon-embedded material were stained by the immunoenzyme technique after removal of epoxy resin. For electron microscopy (EM), ultra-thin sections of Lowicryl K4M-embedded material were stained by the protein A-gold technique. By LM, reaction deposits for cathepsin L were present in the cytoplasmic granules of proximal tubule cells, but little or no reaction product was noted in distal tubule, collecting tubule, and most of urinary tubules in the medulla. By EM, heavy gold label for cathepsin L was confined exclusively to lysosomes of the proximal tubule cells, but little or no label to those of the other segments. In immunocytochemical control sections, no reaction was observed. These results indicate that a main container of cathepsin L is lysosomes of the proximal tubule and suggest that the enzyme plays a role in the degradation of endocytosed proteins.     

Localization of cathepsin L in rat kidney revealed by immunoenzyme and immunogold techniques

Summary Localization of cathepsin L in rat kidney was investigated by immunocytochemical techniques. Kidneys were fixed by perfusion and embedded in Epon or Lowicryl K4M without postomication. For light microscopy (LM), semi-thin sections of the Epon-embedded material were stained by the immunoenzyme technique after removal of epoxy resin. For electron microscopy (EM), ultra-thin sections of Lowicryl K4M-embedded material were stained by the protein A-gold technique. By LM, reaction deposits for cathepsin L were present in the cytoplasmic granules of proximal tubule cells, but little or no reaction product was noted in distal tubule, collecting tubule, and most of urinary tubules in the medulla. By EM, heavy gold label for cathepsin L was confined exclusively to lysosomes of the proximal tubule cells, but little or no label to those of the other segments. In immunocytochemical control sections, no reaction was observed. These results indicate that a main container of cathepsin L is lysosomes of the proximal tubule and suggest that the enzyme plays a role in the degradation of endocytosed proteins.