bluuebunny/crossref_metadata_2025 huggingface dataset:
Anisodamine Inhibits Shiga Toxin Type 2-Mediated Tumor Necrosis Factor-α Production in Vitro and in Vivo
Authors: Zhang Hui-Min , Ou Zhou-Lou , Yamamoto Tatsuo
Published: July 2017

Cytokines, in particular tumor necrosis factor (TNF), appear to be necessary to develop the pathological process of Shiga toxin-producing Escherichia coll (STEC) infection. In this study we examined the effect of anisodamine, a vasoactive drug, on TNF-α production in Shiga toxin type 2 (Stx2)-stimulated human monocytic cells in vitro and in Stx2-injected mice sera in vivo. Human monocytes and THP-1 cells were stimulated by Stx2 (1–100 ng/ml) with or without anisodamine addition (1–400 μg/ml). For in vivo evaluations, C57BL/6 mice were given a single intraperitoneal injection of anisodamine (6–50 mg/kg) or saline after intraperitoneal injection of Stx2 (50 ng/kg). The results showed that anisodamine suppressed Stx2-induced TNF-α production in a dose- and time-dependent manner. Anisodamine also suppressed Stx2-induced TNF-α mRNA expression. Further study showed that endogenous prostaglandin E2 may be involved in this inhibitory effect. In contrast to TNF-α mRNA, anisodamine at concentrations as high as 400 μg/ml did not decrease Stx2-induced IL-1β and IL-8 mRNA levels. In addition, anisodamine (>50 μg/ml) increased Stx2-stimulated THP-1 cell viability. Levels of TNF-α in anisodamine-treated mice sera were significantly lower than those in the saline-treated group 1.5 and 24 hr after Stx2 injection. Anisodamine induced a lower percentage of death in Stx2-injected mice. Taken together, our results indicate that anisodamine has an important regulatory effect on Stx2-induced TNF-α production in vitro and in vivo. The present study suggested that this drug should be further investigated for its effects on Stx2-mediated diseases in humans.
Role of Nitric Oxide in Central Sympathetic Outflow
Authors: Patel Kaushik P. , Li Yi-Fan , Hirooka Yoshitaka
Published: July 2017

The gaseous molecule nitric oxide (NO) plays an important role in cardiovascular homeostasis. It plays this role by its action on both the central and peripheral autonomic nervous systems. In this review, the central role of NO in the regulation of sympathetic outflow and subsequent cardiovascular control is examined. After a brief introduction concerning the location of NO synthase (NOS) containing neurons in the central nervous system (CNS), studies that demonstrate the central effect of NO by systemic administration of NO modulators will be presented. The central effects of NO as assessed by intracerebroventricular, intracisternal, or direct Injection within the specific central areas is also discussed. Our studies demonstrating specific medullary and hypothalamic sites involved in sympathetic outflow are summarized. The review will be concluded with a discussion of the role of central NO mechanisms in the altered sympathetic outflow in disease states such as hypertension and heart failure.
Drug-Induced Phospholipidosis: Are There Functional Consequences?
Authors: Reasor Mark J. , Kacew Sam
Published: July 2017

Phospholipidosis induced by drugs with a cationic amphiphilic structure is a generalized condition in humans and animals that is characterized by an intracellular accumulation of phospholipids and the concurrent development of concentric lamellar bodies. The primary mechanism responsible for the development of phospholipidosis is an inhibition of lysosomal phospholipase activity by the drugs. While the biochemical and ultrastructural features of the condition have been well characterized, much less effort has been directed toward understanding whether the condition has adverse effects on the organism. While there are a few cationic amphiphilic drugs that have been reported to cause phospholipidosis in humans, the principal concern with this condition is in the pharmaceutical industry during preclinical testing. While this class of drugs should technically be referred to as cationic lipophilic, the term cationic amphiphilic is widely used and recognized in this field, and for this reason, the terminology cationic amphiphilic drugs (CADs) will be employed in this Minireview. The aim of this Minireview is to provide an evaluation of the state of knowledge on the functional consequences of CAD-induced phospholipidosis.
Maximum Life Spans in Mice are Extended by Wild Strain Alleles
Authors: Klebanov Simon , Astle Clinton M. , Roderick Thomas H. , Flurkey Kevin , Archer Jonathan R. , Chen Jichun
Published: July 2017

The genes that control basic aging mechanisms in mammals are unknown. By using two four-way crosses, each including a strain derived from wild, undomesticated stocks, we identified two quantitative trait loci that extend murine life spans by approximately 10%. In one cross, the longest-lived 18% of carriers of the D8MH171 marker allele from the MOLD/Rk strain, Mus m. molossinus, outlived the longest lived 18% of noncarriers by 129 days (P = 5.4 × 10–5); in a second cross, carriers of the D10Mit267 allele from the CAST/El strain, Mus m. castaneus, outlived noncarriers by 125 days (P = 1.6 × 10–6). In both crosses, P < 1.0 × 10–4 is considered significant. Because these life span increases required that all essential biological systems function longer than normal, these alleles most likely retarded basic aging mechanisms in multiple biological systems simultaneously.
Clinical Investigation: But Why?
Authors: Hazzard William R.
Published: July 2017

We are fortunate to have the opportunity to publish this reflection on the process of clinical research. Dr. Hazzard has had a distinguished career as the director of one of the original clinics of the NIH Lipid Research Clinics Program as vice chairman and chairman, respectively, of the Departments of Medicine at Johns Hopkins and Wake Forest Medical Schools and as a leading gerontologist, now at the University of Washington. As Dr. Hazzard makes clear, the problems facing the clinical researcher are many but the rewards are also many. The challenge is to keep open the door to such a career and to encourage the success of those who pass through., Robert H. Knopp MD Past-President, SEBM
Attenuated Agonist Evoked Vasoconstrictor Responses in the Perfused Mesenteric Vascular Bed of Streptozotocin Diabetic Rats
Authors: Misurski Derek A. , Hopfner Robert L. , Gopalakrishnan Venkat
Published: July 2017

We compared agonist-evoked responses In the perfused mesenteric vascular bed (MVB) of streptozotocin (STZ) diabetic Sprague-Dawley rats 2 and 14 weeks after induction of diabetes. Endothelin-1 (ET-1)-, methoxamine (MTX)-, and KCI-evoked vasoconstrictor responses were unchanged In 2-week-old diabetic rats. In contrast, both the sensitivity (P < 0.01) and the maximal vasoconstrictor responses (P < 0.05) to ET-1 were attenuated in 14-week-old diabetic rats, whereas endothelin plasma levels were increased (P < 0.05). Although no differences were observed in responses to KCl in either the 2- or 14-week-old diabetic groups, MTX-evoked maximal responses were attenuated in the 14-week-old group (P < 0.01). Changes in agonist-evoked responses in the 14-week-old diabetic group were unaffected by the protein kinase C (PKC) inhibitor, staurosporine, the phospholipase C (PLC) inhibitor, U73122, the calcium channel blocker, nifedipine, the calcium pump inhibitor, cyclopiazonlc acid (CPA), or by endothelial denudation. Sodium fluoride (NaF), an activator of guanosine triphosphate binding proteins (G proteins) normalized the responses in the 14-week-old diabetic group. These data suggest that advanced stages of STZ are associated with alterations in G protein receptor coupling and/or activity leading to the attenuation of responses to vasoconstrictor agonists.
Effect of Epristeride on the Expression of IGF-1 and TGF-β Receptors in Androgen-Induced Castrated Rat Prostate
Authors: Wu Shu-Fang , Sun Hong-Zhi , Qi Xiao-Dong , Tu Zeng-Hong
Published: July 2017

The development of benign prostatic hyperplasia (BPH) Is an androgen-dependent process that may be mediated by a number of locally produced growth factors. Among them, insulin-like growth factor 1 (IGF-1) and transforming growth factor β (TGFβ) are thought important in regulating prostate growth and homeostasis, and their expression undergoes changes in proliferative prostatic disease. Epristeride, a 5α-reductase inhibitor, is an effective drug in the treatment of BPH, inducing regressive changes in the prostate. This study was designed to assess the effects of epristeride on expression of these two factors at mRNA and protein levels in castrated rats maintained with exogenous testosterone. Epristeride treatment caused significant reduction in ventral prostate weight in a dose-dependent manner. There was a positive correlation between IGF-1 mRNA expression and ventral prostate weight and an inverse correlation between TGF-β1 mRNA expression and ventral prostate weight. Immunohistochemistry showed strong IGF-1 receptor immunoreactivity in the prostatic epithelial cells of untreated animals. In situ hybridization demonstrated high levels of IGF-1 mRNA expression both in the prostatic stromal and epithelial cells of untreated rats. In treated rats, both IGF-1 receptor protein and IGF-1 mRNA levels decreased significantly, and IGF-1 mRNA was mainly expressed in prostatic stromal cells. Weak expression of TGFβ receptors at the protein level and TGFβ at the mRNA level were found in the prostatic hyperplastic epithelial cells of untreated rats. In treated animals, intense TβRII immunoreactivity was observed in epithelial cells, and a higher level of TGFβ mRNA was observed in both epithelial cells and stromal cells compared with control animals. In our opinion, the effect of epristeride on rat prostatic atrophy might be mediated via local growth factor(s).
Chelated Metal Ions for Therapeutic and Diagnostic Applications
Authors: Brechbiel Martin W.
Published: July 2017

Use of radiolabeled monoclonal antibodies (mAb's) that localize and bind to malignant cells continues to be an attractive mechanism for targeting and delivering either an imagable isotope, be It a y-emitter or B+-emitter, or a particle emitter such as a B—emitter or an a-emitter for therapeutic applications.
Regulation of PECAM-1 in Endothelial Cells during Cell Growth and Migration
Authors: RayChaudhury Amlan , Elkins Marne , Kozien Dianna , Nakada Marian T.
Published: July 2017

Endothelial cells (EC) that form the inner lining of blood vessels remain quiescent in the normal adult vasculature except during angiogenesis and reendothelialization, which result in EC proliferation and migration. EC placed in culture at subconfluent density also undergo cell multiplication and movement. This report demonstrates that whereas in confluent EC in a compact monolayer, the EC-EC adhesion molecule platelet-endothelial cell adhesion molecule-1 (PECAM-1) is strongly expressed at cell borders, little or no PECAM-1 immunostaining is detected in sparse or migrating cultured EC. Consistent with this observation, steady-state PECAM-1 mRNA expression was much lower in subconfluent EC than in confluent EC. The absence of PECAM-1 expression in sparse EC appeared not to be linked to ability to proliferate, since PECAM-1 expression remained low even in the presence of nitric oxide (NO) or mitomycin C, agents that inhibit EC growth. However, another growth-inhibitory agent, TGF-β1, did not alter PECAM-1 staining. Based on these observations, it is hypothesized that cell-associated mechanical forces underlying cell tensegrity regulate PECAM-1 expression.
Dehydroepiandrosterone Alters Zucker Rat Soleus and Cardiac Muscle Lipid Profiles
Authors: Abadie Jude M. , Malcom Gray T. , Porter Johnny R. , Svec Frank
Published: July 2017

High levels of serum free fatty acids (FFA) and lower proportions of polyunsaturated (PU) FAs, specifically arachidonic acid (AA), are common in obesity, insulin resistance (IR), and type 2 diabetes mellitus. Dehydrepiandrosterone (DHEA) decreases body fat content, dietary fat consumption, and insulin levels in obese Zucker rats (ZR), a genetic model of human youth onset obesity and type 2 diabetes. This study was conducted to investigate DHEA's effects on lean and obese ZR serum FFA levels and total lipid (TL) FA profiles in heart and soleus muscle. We postulated that DHEA alters serum FFA levels and tissue TL FA profiles of obese ZR so that they resemble the levels and profiles of lean ZR. If so, DHEA may directly or indirectly alter tissue lipids, FFA flux, and perhaps lower IR in obese ZR. Lean and obese male ZR were divided into six groups with 10 animals in each: obese ad libitum control, obese pair-fed, obese DHEA, lean ad libitum control, lean pair-fed, and lean DHEA. All animals had ad libitum access to a diet whose calories were 50% fat, 30% carbohydrate, and 20% protein. Only the diets of the DHEA treatment groups were supplemented with 0.6% DHEA. Pair-fed groups were given the average number of calories per day consumed by their corresponding DHEA group, and ad libitum groups had 24-h access to the DHEA-free diet. Serum FFA levels and heart and soleus TL FA profiles were measured. Serum FFA levels were higher in obese (~1 mmol/L) compared to lean (~0.6 mmol/L) ZR, regardless of group. In hearts, monounsaturated (MU) FA were greater and PU FA were proportionally lower in obese compared to the lean rats. In soleus, saturated and MU FA were greater and PU FA were proportionally lower in the obese compared to the lean rats. DHEA groups displayed significantly increased proportions of TL AA and decreased oleic acid in both muscle types. Mechanisms by which DHEA alters TL FA profiles are a reflection of changes occurring within specific lipid fractions such as FFA, phospholipid, and triglyceride. This study provides initial insights into DHEA's lipid altering effects.
Matrix Metalloproteinases-2 and 9 Do Not Play a Role in the Growth of Preneoplastic Liver Lesions in F344 Rats
Authors: Wood Geoffrey A. , Archer Michael C.
Published: July 2017

Matrix metalloproteinases- (MMPs) 2 and 9 (gelatinases A and B) have been implicated in tumor invasion and metastasis, and recent studies have shown increased levels of these enzymes during recovery from partial hepatectomy (PH) in rats. F344 rats are highly susceptible to the growth of glutathione S-transferase 7-7- (GST 7-7) positive preneoplastic liver lesions promoted using the modified resistant hepatocyte (RH) protocol. Since the RH protocol consists of 2-acetylaminofluorene (2-AAF) followed by a PH, we reasoned that MMP-2 and -9 might be critical for the growth of lesions. Using gelatin zymography, we examined the expression of these enzymes in the livers of F344 rats treated with the RH protocol and sacrificed on Days 2, 4, 7, 14, and 21 after 2-AAF/PH. We found increases in both pro- and active MMP-2 and -9 over baseline levels, with the highest levels occurring on Day 7 post-PH. Also, a 54-kDa band, likely to be proMMP-1, was elevated in a pattern similar to MMP-2 and -9. In contrast to F344 rats, identically treated Copenhagen rats that are highly resistant to promotion of liver lesion growth using the RH protocol had significantly lower levels of proMMP-1 and -2. To test the importance of these MMPs to the growth of liver lesions, F344 rats that had been initiated with diethylnitrosamine were treated using the RH protocol. They then received either the MMP inhibitor batimastat (30 mg/kg, intraperitoneally) or vehicle alone daily from Day 3 to 20 post-PH and were sacrificed on Day 21. There were no differences in the percentage of liver volume occupied by GST 7-7-positive lesions (19.1 ± 4.84 vs 19.4 ± 3.31, treated versus vehicle, mean ± SEM) or liver weight as a percentage of body weight (4.11% ± 0.15 vs 4.07% ± 0.18, treated versus vehicle, mean ± SEM) between the treated and control groups. Treatment of rats with batimastat clearly did not affect lesion growth or liver regeneration following the RH protocol. These results suggest that increases in gelatinase expression during the RH protocol are a result of the promotional stimulus rather than a mechanism by which 2-AAF/PH causes lesion growth.
Bioenergetics of Adaptation to a Salinity Transition in Euryhaline Teleost (Oreochromis mossambicus) Brain
Authors: Weng Ching-Feng , Chiang Chia-Chang , Gong Hong-Yi , Chen Mark Hung-Chih , Huang Wei-Tung , Cheng Ching-Yi , Wu Jen-Leih
Published: July 2017

Freshwater (FW) teleosts are capable of acclimating to seawater (SW) following such a transfer from FW. However, their osmo-regulating mechanisms are still unclear, particularly those in the brain. The present study was conducted to examine acute changes that occur in brain Na+-K+-ATPase activity, creatine kinase (CK) activity, creatine, creatinine contents, and ATP levels of tilapia (Oreochromis mossambicus) in response to this transition. After transfer to SW (25 ppt), the Na+-K+-ATPase activity was maintained for 8 hr at higher levels than that in FW. In contrast, in 35 ppt SW, Na+-K+-ATPase was maintained at a even higher level than in FW for the first 2 hr. Brain Na+-K+-ATPase contents in both the 25 and 35 ppt SW groups were significantly elevated within 1 and 0.5 hr after transfer from FW, respectively. Interestingly, brain CK activities and content (homodimer of the B subunit [BB] form) in both the 25 and 35 ppt SW groups were significantly elevated within 1 hr after transfer from FW. The ATP contents in 35 ppt SW increased abruptly within 0.5 hr, and then gradually decreased during the next 2 hr. Unlike the 35 ppt group that declined in ATP contents, the 25 ppt group leveled off within 24 hr. The elevations in CK activity and creatine levels after transfer from FW to SW imply that abrupt salinity changes alter phosphocreatine/CK ratio. Such changes are needed to satisfy the increases in the energetic requirement of the cotransport mechanisms mediating osmoregulation
Effects of Growth Hormone and Insulin-Like Growth Factor-1 on Hepatocyte Antioxidative Enzymes
Authors: Brown-Borg Holly M. , Rakoczy Sharlene G. , Romanick Mark A. , Kennedy Melissa A.
Published: July 2017

The physiological decline that occurs in aging is thought to result, in part, from accumulation of oxidative damage generated by reactive oxygen species during normal metabolic processes. Elevated levels of antioxidative enzymes in liver tissues are present in the Ames dwarf, a growth hormone (GH)-deficient mouse that lives more than 1 year longer than wild-type mice from the same line. In contrast, transgenic mice that overexpress GH exhibit depressed hepatic levels of catalase and have significantly shortened life spans. In this study, we evaluated the in vitro effects of GH and Insulin-like growth factor 1 (IGF-1) on antioxidative enzymes in mouse hepatocytes. Hepatocytes were isolated from wild-type mice following perfusion of livers with a collagenase-based buffer. Dispersed cells were plated on Matrlgel and treated with rat GH (0.1, 1.0, or 10 μg/ml) or IGF-1 (0.5, 5.0, or 50 nM) for 24 hr. Hepatocytes were recovered and protein was extracted for immunoblotting and enzyme activity assays of catalase (CAT), glutathione peroxidase (GPX), and manganese superoxide dismutase (MnSOD). A 41% and 27% decrease in catalase activity was detected in cells treated with GH, whereas IGF-1 reduced CAT activity levels to a greater extent than GH (P < 0.0001). The activity and protein levels of GPX were also significantly depressed In cells treated with GH, whereas activity alone was decreased in cells treated with IGF-1 (P < 0.04). GH significantly suppressed MnSOD levels by 40% and 66% in 1.0 and 0.1 μg/ml concentrations, respectively. Similarly, IGF-1 decreased MnSOD protein levels (5 nM; P < 0.05). These results suggest that GH and IGF-1 may decrease the ability of hepatocytes to counter oxidative stress. In addition, these experiments provide an explanation for the differing antioxidative defense capacity of GH-deficient versus GH-overexpressing mice, and they suggest that GH is directly involved in antioxidant regulation and the aging process.
Effect of Massive Sympathetic Nervous System Activation on Coronary Blood Flow and Myocardial Energy Pool
Authors: Smith Jennifer M. , Pilati Charles F.
Published: July 2017

Our previous work Indicates that myocardial Ischemia could be the mechanism responsible for the left ventricular (LV) dysfunction that frequently develops after massive sympathetic nervous system (SNS) activation. In this study, coronary blood flow (CBF) and myocardial ATP, creatine phosphate, and lactate concentrations were measured after massively activating the SNS of anesthetized rabbits with an intraclsternal injection of veratrine. CBF was measured at time 0 (baseline), and at 2, 10, and 20 min after SNS activation in one group, and at 0, 45, 90, and 150 min in a second group. Myocardial ATP, creatine phosphate, and lactate were measured at 0, 2, 10, 20, 90, and 150 min in separate groups of rabbits. SNS activation caused LV dysfunction in –60% of the rabbits. SNS-related increases in CBF kept pace with the Increases in myocardial energy demand as determined from the systolic pressure-heart rate product. The subendocardial-to-subepicardlal blood flow ratio did not change significantly. Myocardial creatine phosphate concentration was depressed 2 min after SNS activation and remained depressed for at least 20 min. ATP fell continuously and was significantly lower than baseline by 20 min. Tissue lactate concentration was elevated at this time. By 90 min, the concentrations of all three metabolites had recovered. These results indicate that myocardial high-energy phosphate compounds fall after massive SNS activation, but ischemia does not appear to be the underlying mechanism.
Increased Beef Consumption Increases Apolipoprotein A-I but Not Serum Cholesterol of Mildly Hypercholesterolemia Men with Different Levels of Habitual Beef Intake
Authors: Smith Dana R. , Wood Randall , Tseng Stephen , Smith Stephen B.
Published: July 2017

The objective of this research was to compare the effects of a lean beef enriched in oleic acid to a beef that is typical of the commercial beef consumed in the United States. Ten mildly hypercholesterolemic men, ages 34-58 years old, were selected from the Texas A&M University faculty and staff. Subjects were randomly assigned to one of two diets for a 6-week duration followed by a crossover after a 4-week habitual diet washout period. Diets were consumed daily for a 6-week study period. Participants substituted lean beef obtained from Wagyu bullocks or commercial beef for the meat typically consumed. Total cholesterol, apolipoproteins A-I and B, triacylglycerols, and low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol were measured in serum samples collected weekly. Beef type had no effect on any measured variable. There were no significant differences between baseline HDL or LDL cholesterol concentrations after the consumption of the beef test diets. Apolipoprotein A-I, serum glucose, and uric acid concentrations were elevated by the additional dietary beef. Analysis of records of customary diets indicated that one group consumed 160 g of beef daily, whereas the other group consumed only 26 g of beef daily. Therefore, post hoc analyses tested the habitual beef intake x treatment time interaction. LDL cholesterol concentration was markedly higher in the group with low habitual beef Intake (180 vs 144 mg/dl), and HDL cholesterol was slightly higher (44 vs 40 mg/dl; post-test values) than for the group with high habitual beef intake, but there were no habitual intake x time interactions for LDL or HDL cholesterol. Creatinine and blood urea nitrogen concentrations also were greater in the individuals habitually consuming less beef. This study had three important findings: i) a lean beef source enriched with oleic acid was no different from commercial beef in its effect on lipoprotein fractions; ii) neither previous level of beef intake nor baseline LDL cholesterol concentration influenced the serum cholesterol response to added dietary beef. which was negative; and iii) apolipoprotein A-I, but not HDL or LDL cholesterol, was sensitive to the additional dietary beef.
The GABAB Antagonist CGP 52432 Attenuates the Stimulatory Effect of the GABAB Agonist SKF 97541 on Luteinizing Hormone Secretion in the Male Sheep
Authors: Jackson Gary L. , Kuehl David
Published: July 2017

The objectives of this study were to determine if the c-aminobutyric acid (GABA)B agonist, 3-aminopropyl (methyl) phosphinic acid (SKF97541), would increase luteinizing hormone (LH) secretion when infused by microdialysis into the medial basal hypothalamus (MBH) of the castrated ram, and to determine if the action of SKF97541 would be attenuated by coinfusion of the GABAB antagonist CGP52432. Initial experiments established that infusion of SKF alone, at concentrations as low as 5 μM, increased mean LH, LH pulse amplitude, and in some cases, pulse interval. In the last experiment, animals were treated with artificial cerebrospinal fluid (CSF) alone, SKF alone (30 μM), 3-[[(3, 4-dichlorophenol) methyl] amino] propyl] dieth-oxymethyl) phosphinic acid (CGP) alone (500 μM), or SKF plus CGP. SKF increased both mean LH and LH pulse amplitude as compared with CSF. CGP alone had no significant effect on LH, but it attenuated the effect of SKF on mean LH. These observations indicate that the stimulatory effects of GABAB agonists on LH pulse patterns are mediated through GABAB receptors and provide further evidence that GABAB receptors located in the MBH can regulate pulsatile GnRH-LH release.
Release of Cytokines by Human Nasal Epithelial Cells and Peripheral Blood Mononuclear Cells Infected with Mycoplasma pneumoniae
Authors: Kazachkov Mikhail Y. , Hu P.C. , Carson Johnny L. , Murphy Paula C. , Henderson Frederick W. , Noah Terry L.
Published: July 2017

Mycoplasma pneumoniae (Mp) infection is associated with asthma exacerbation in children. We hypothesized that Mp infection may cause airway inflammation by inducing the release of cytokines by respiratory epithelial cells. The levels of chemokines interleukin-8 (IL-8) and released upon activation, normal t cell expressed and secreted (RANTES) released by nasal epithelial cell (NEC) cultures established from asthmatic and nonasthmatic children were measured by ELISA at 4, 24, 48, and 72 hr after cells were inoculated with Mp, and were compared with baseline release of these factors. The presence of MP on apical membranes of NEC after infection was confirmed by transmission electron microscopy, and adherence was shown to be inhibited by erythromycin. Mp infection did not alter NEC release of IL-8 or RANTES at any time point. In contrast, tumor necrosis factor α (TNF-α) stimulated increased IL-8 at all time points, and respiratory syncytial virus (RSV) infection stimulated RANTES release at 48 and 72 hr by NEC. These results were not significantly different between NEC from asthmatic and nonasthmatic children. As a comparison, peripheral blood mononuclear cells from normal human volunteers were also incubated with Mp and had significantly increased release of IL-2, IL-6, and TNF-α. We conclude that Mp, unlike viral pathogens such as RSV, is unlikely to directly stimulate early airway surface cytokine responses via mechanisms involving epithelial cells. We speculate that the chronic presence of mononuclear cells at the airway surface of asthmatics provides a target for Mp-triggered cytokine production.
Different Pathways of Cell Killing by Gossypol Enantiomers
Authors: Qiu Jianping , Levin Lonny R. , Buck Jochen , Reidenberg Marcus M.
Published: July 2017

Gossypol, a polyphenolic, aldehyde-containing constituent of cottonseed, produced partial responses (>50% reduction in tumor size) in some patients with advanced cancer and suppressed sperm as an antifertility agent for men. This action in vivo and its novel side effect profile suggest a specific mechanism of the action of gossypol. Using the random homozygous knockout approach of Li and Cohen (1), we developed a cell line resistant to killing by gossypol, but sensitive to methotrexate and doxorubicin. It showed stereospecific resistance to killing by (–) gossypol (ED50 4.9 μM) compared with wild type (ED50 2.0 μM). The resistant and wild-type cells were equally sensitive to (+) gossypol (ED50 8.8 and 8.4 μM, respectively), methotrexate, and doxyrubicin. We conclude that gossypol affects cells by a stereospecific pathway for (–) gossypol, possibly related to its selective effects, and a nonstereospecific pathway for (+) gossypol and higher concentrations of (-) gossypol. Further knowledge about the stereospecific pathway may lead to new therapeutic drugs.
Transforming Growth Factor-β1 is Responsible for Maturation-Dependent Spontaneous Apoptosis of Cultured Gastric Pit Cells
Authors: Tsutsumi Shinji , Tomisato Wataru , Hoshino Tatsuya , Tsuchiya Tomofusa , Mizushima Tohru
Published: July 2017

In this study, we established a system of high concentration serum-dependent spontaneous apoptosis of guinea pig gastric pit cells in primary culture, which seems to mimic the spontaneous apoptosis of matured gastric pit cells at gastric surface in vivo. In addition to induction of the spontaneous apoptosis, cell growth was inhibited in the presence of 10% serum compared with 0.5% serum. Transforming growth factor-β1 (TGF-β1), which is known to cause both apoptosis and growth inhibition in mammalian cells, was present in serum of both fetal calf and guinea pig. The addition of recombinant TGF-β1 to the culture medium containing 0.5% fetal calf serum caused both induction of apoptosis and inhibition of cell growth. On the other hand, immunodepletion of TGF-β1 from fetal calf serum caused inability to induce both the spontaneous apoptosis and inhibition of cell growth. These data suggest that TGF-β1 is involved in the spontaneous apoptosis of guinea pig gastric pit cells in primary culture.
Letter to the Editor
Authors: Bartke A. , White Milton W.
Published: July 2017

The following comments by Dr. White propose novel and provocative ideas concerning the origin and biology of cancer. It was not subjected to peer review and thus should not be considered as representing the opinions of the Editorial Board of EBM or the Society. Comments on the ideas expressed in this letter are welcome and will be considered for publication.
Age-Related Changes in the Regulation of Luteinizing Hormone Secretion by Estrogen in Women
Authors: Park Susanna J. , Goldsmith Laura T. , Weiss Gerson
Published: July 2017

Despite the many studies that have been conducted using both primate and human models to understand the control of the menstrual cycle, there are many aspects of the hormonal dynamics of the menstrual cycle that are not understood. This Minireview summarizes the changes in estrogen regulation of luteinizing hormone (LH) secretion that occur throughout life in women from the time of maturation of the hypothalamic-pituitary axis resulting in the occurrence of the LH surge during puberty, through the reproductive years, to the changes in the regulation of the LH surge during premenopause and, subsequently, menopause.
Serial Transplantation of p53-Deficient Hemopoietic Progenitor Cells to Assess Their Infinite Growth Potential
Authors: Hirabayashi Yoko , Matsuda Motoi , Aizawa Shin-Ichi , Kodama Yukio , Kanno Jun , Inoue Tohru
Published: July 2017

Thirty-five years ago, Siminovitch et al. (Siminovitch L, Till JE, McCulloch EA. J Cell Com Physiol 64:23–32, 1964), using serially transplanted mouse spleens at 14-day intervals, observed a markedly progressive decline in the proliferative capacity of bone marrow (BM) cells, with the loss of cionogenicity by the fourth transplant generation. Using the same protocol, we assessed the proliferative capacity of p53-deficient mouse BM cells transplanted serially at the same 14-day intervals into lethally irradiated mice, which was a useful tool for understanding the characteristics of hemopoletic stem cells lacking solely the p53 gene function. BM cells from p53-deficient homozygous (p53–/–), p53-heterozygous (p53+/–), and wild-type (p53+/+) C57BL/6 mice were transplanted into lethally irradiated C57BL/6 recipients. Fourteen days later, the repopulated spleens were harvested, and 107 cells were retransplanted into secondary recipients. Serial transplantation was continued at 14-day intervals until hemopoietic repopulation failure. The number of heterozygous and homozygous p53-deficient spleen cells increased logarithmically up to the fourth and fifth passages, respectively, whereas wild-type spleen cells ceased to proliferate by the third passage. The number of macroscopic spleen colonies increased logarithmically until the third passage in recipients of heterozygous and homozygous p53-deficient cells, but ceased to grow by the second passage in recipients of wild-type cells. The numbers of heterozygous and homozygous p53-deficient colony forming units in spleen (CFUs-S) remained stable during the first four transplant generations, whereas that of wild-type CFUs-S decreased progressively from the first transplant generation onward. The clonogenicity of p53-deficient cells was lost when the number of CFUs-S per spleen decreased to below 10. This suggests that one out of 10 CFUs-S might be long-term repopulating cells (LTRCs), and that p53-deficient LTRCs may proliferate more rapidly than wild-type LTRCs. Longer passages that were possible in the p53-deficient groups were considered to be due to the faster cell cycle of the p53-deficient hemopoietic progenitor cells, as determined by bromodeoxyuridine incorporation with purging by UV light exposure, followed by hemopoietic colony assay (BUUV assay).
Neointima Formation in the Rat Carotid Artery is Exacerbated by Dietary Copper Deficiency
Authors: Lucca Jurandir J. Dalle , Saari Jack T. , Falcone Jeff C. , Schuschke Dale A.
Published: July 2017

Dietary copper is an essential trace element with roles in both functional and structural aspects of the cardiovascular system. In particular, the vascular response to inflammatory stimuli is known to be significantly augmented in copper-deficient rats. The current study was designed to quantify the extent of injury-induced neointimal proliferation and stenosis in rats fed diets either adequate or deficient in copper. Male, weanling Sprague-Dawley rats were fed purified diets that were either adequate (CuA; 5.6 μg Cu/g) or deficient (CuD; 0.3 μg Cu/g) in copper for 4 weeks. Balloon injury was induced in the left external carotid arteries. Fourteen days after injury, histomorphometric analysis of cross-sections from carotid arteries showed increased neointimal formation in the CuD group compared with the CuA controls (neointima/media ratio: 4.55 ± 0.93 vs 1.45 ± 0.2, respectively). These results correspond with data indicating that the activity of Cu/Zn-superoxide dismutase (SOD) is depressed in rats fed this CuD diet. Because superoxide anion and redox status are known to play a key role in the extent of neointimal formation in response to injury, we propose that the exaggerated neointimal proliferation seen in the CuD group is the result of the diminished Cu/Zn-SOD activity.
Humoral Immune Response in Mice Over-expressing or Deficient in Growth Hormone
Authors: Hall Mary A. , Bartke Andrzej , Martinko John M.
Published: July 2017

Effects of growth hormone (GH) levels on the humoral immune response were investigated in metallothionein I (MT)-bovine (b) GH-transgenic (tg) and GH-deficient Ames dwarf (Prop1 dt–/–) mice. Four-month-old mice were given primary and secondary injections of either normal saline or tetanus toxoid (TT) to induce specific antibody (Ab) production. MT-bGH-tg mice with high peripheral levels of bGH produced less TT-specific Ab than normal nontransgenic (Ntg) littermates, df, or nondwarf (Ndf) control mice. Titers reached maximum levels at 3–4 weeks postprimary immunization (PPI) and declined gradually through 24 weeks PPI in all groups of mice. Peripheral CD4+and CD8+T cell populations were significantly lower in tg than in Ntg, df, or Ndf mice. No significant differences were found in B cell numbers between tg, Ntg, or df mice. T helper 2 (Th2) cell populations were significantly greater in df mice compared to Ntg control mice. No significant differences were found in CD4+:CD8+T cell ratios, interleukin (IL)-4 concentrations or interferon (IFN)-γ levels between tg, Ntg, df, and Ndf mice. No patterns of significant sexual dimorphism were found for any of the immune parameters studied. Elevated levels of corticosterone were investigated as a possible immunosuppressant mechanism responsible for low Ab responses in the tg mice. Ab production was not enhanced by decreasing corticosterone in tg mice. Thus, high endogenous GH levels inhibit specific Ab production and peripheral T cell populations but not peripheral B cell numbers, Th2 cell populations, or IL-4 or IFN-gamma production. Elevated corticosterone levels do not appear to be responsible for suppressed humoral immune responses. Low levels of endogenous GH do not inhibit specific Ab production but may contribute to increased peripheral Th2 cell numbers.
Absence of p53 and FasL Has Sexually Dimorphic Effects on Both Development and Reproduction
Authors: Embree-Ku Michelle , Boekelheide Kim
Published: July 2017

Reproduction and development are highly dependent on apoptosis to balance the proliferation that necessarily occurs during these processes. How the absence of two apoptotic factors in mice would affect reproduction and development was examined. Given previous reports of increased neural tube defects in p53–/– female fetuses, decreased fertility in gld female mice, and altered spermatogenesis in both p53 and gld male mice, the possibility that these phenotypes might be enhanced by the elimination of a second apoptotic factor was investigated. The reproductive vigor and the health of offspring were monitored during the production of the new double-deficient strain (FasL–/–p53–/–) for any changes from the reported phenotypes. Thus, any unusual phenotypes that could lead to new models for studying mechanisms of health and disease would be identified. Double-deficient male offspring appeared healthy and occurred at expected frequencies. Additionally, spermatogenesis and male fertility were unaffected by the gene deficiencies. On the other hand, FasL+/+p53–/– and FasL–/–p53–/– female mice were susceptible to increased malformations and post-natal death. These abnormalities were consistent with previous reports of neural tube defects in p53–/– female mice. Fertility rates were also significantly decreased in p53-/- female mice that lived to be adults, an observation not previously reported. Finally, the absence of both FasL and p53 led to dystocia in pregnant female mice, suggesting that the two genes play complementary roles in parturition. Therefore, although male mouse development and reproduction remained unaffected by p53 and FasL deficiencies, female mouse development was adversely affected by the absence of p53, and no live litters were born to female mice with the combined absence of both FasL and p53. In this report, we suggest a potential mechanism involving corpora luteal regression to explain this defect in parturition in FasL–/–p53–/– female mice.
Mismatch Repair Genes and Microsatellite Instability as Molecular Markers for Gynecological Cancer Detection
Authors: Miturski Roman , Bogusiewicz Michał , Ciotta Carmella , Bignami Margherita , Gogacz Marek , Burnouf Dominique
Published: July 2017

Due to major developments in genetics over the past decade, molecular biology tests are serving promising tools in early diagnosis and follow-up of cancer patients. Recent epidemiological studies revealed that the risk for each individual to develop cancer is closely linked to his/her own genetic potentialities. Some populations that are defective in DNA repair processes, for example in Xeroderma pigmentosum or in the Lynch syndrome, are particularly prone to cancer due to the accumulation of mutations within the genome. Such populations would benefit from the development of tests aimed at identifying people who are particularly at risk. Here, we review some data suggesting that the inactivation of mismatch repair is often found in endometrial cancer and we discuss molecular-based strategies that would help to identify the affected individuals in families with cases of glandular malignancies.
Actions of Immunosuppressor Drugs on the Development of an Experimental Ovarian Tumor1
Authors: Sorianello E. , Schillaci R. , Chamson-Reig A. , Lux-Lantos V. , Libertun C.
Published: July 2017

Immunosuppression has been related to the incidence of tumor apparition, including endocrine tumors. The intrasplenic ovarian tumor (luteoma) is a typical benign endocrine tumor that develops under high gonadotropin stimulation and, from the immunological perspective, is located in a critical organ involved in immune response. To establish if immunosuppression could alter the development of this experimental tumor, the effects of cyclosporin A (CsA) and dexamethasone (Dex) were evaluated. After surgery, tumor-bearing and sham animals were kept without treatment for 4 weeks; thereafter, they were distributed into CsA (25 mg/kg), Dex (0.1 mg/kg), or vehicle (75:25 castor oll:ethanol) groups and were injected on alternate days for 50 days. Body weight was evaluated weekly. Animals were sacrificed after a jugular vein blood sample was obtained. Thymi were weighed. Tumors were measured and placed in formaline for histological studies. Serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PRL), and estradiol were measured by radioimmunoassay. Hematological parameters were determined. CsA induced a significant decrease in survival rates both in tumor-bearing and sham animals (P < 0.01). Dex significantly impaired weight increase in both groups of animals. CsA induced a significant weight loss in sham animals, not observed in tumor-bearing animals. Dex induced thymus weight loss in both groups, whereas CsA induced thymus weight loss only in sham animals. Only Dex induced a decrease in lymphocyte number in both groups. CsA induced an increase in monocyte number only in sham animals. Treatments did not alter LH, FSH, or estradiol, whereas PRL was increased by CsA only in sham rats. Neither Dex nor CsA induced any significant variations in tumor volume, nor did they alter tumor histology. In addition, no visible metastases or alterations in other organs were observed. We conclude that, though immunological parameters were altered by the treatments, immunosuppressor drugs did not condition tumor development. In addition, tumors secrete one or more factor/s that counteract CsA effect.
Glucocorticoid-Induced Apoptosis in Early B Cells from Human Bone Marrow
Authors: Lill-Elghanian Deborah , Schwartz Kenneth , King Louis , Fraker Pam
Published: July 2017

The sensitivity of normal human lymphoid precursor cells to glucocorticoid-induced apoptosis is a subject of controversy. The in vitro response of cells of the B lineage (CD19+) from the marrow of 22 adult subjects to glucocorticoids was evaluated herein using both natural steroids and dexamethasone (Dex). When exposed to 1 μM Dex, 32% of the subjects exhibited high losses of CD19+B cells in the range of 45%. The remaining subjects exhibited more modest losses in CD19+cells of 26%–40%. Surprisingly, cortisol, a naturally produced glucocorticoid, produced B lineage losses nearly equivalent to Dex, which reached maximum by 12 hr. It was subsequently noted that the variances in losses of CD19+cells among the subjects correlated closely with the proportion of early CD10+CD19+B cells present in the initial population. The latter cells exhibited a high degree of sensitivity to glucocorticoids, with losses of 60%–80% noted. Mature B cells bearing IgD, on the other hand, were fairly resistant to glucocorticoids. Merocyanine 540, a membrane dye that fluoresces in the disordered membrane of apoptotic cells, confirmed that early or progenitor B cells in human bone marrow were indeed undergoing glucocorticoid-induced apoptosis, which could be blocked by the glucocorticoid antagonist RU38486. These data provide evidence that human marrow B cells, especially early B-cell progenitors, are quite sensitive to glucocorticoids and readily undergo apoptosis within a few hours of exposure to the steroids.
Lamprey GnRH-III Acts on Its Putative Receptor via Nitric Oxide to Release Follicle-Stimulating Hormone Specifically
Authors: Yu W.H. , Karanth S. , Mastronardi C.A. , Sealfon S. , Dean C. , Dees W.L. , McCann S.M.
Published: July 2017

Lamprey gonadotropin-releasing hormone-III (I-GnRH-III), the putative follicle-stimulating hormone (FSH)-releasing factor (FSHRF), exerts a preferential FSH-releasing activity in rats both in vitro and in vivo. To test the hypothesis that I-GnRH-III acts on its own receptors to stimulate gonadotropin release, the functional activity of this peptide at mammalian (m) leutinizing hormone (LH)RH receptors transfected to COS cells was tested. I-GnRH-III activated m-LHRH receptors only at a minimal effective concentration (MEC) of 10–6M, whereas m-LHRH was active at a MEC of 10–9M, at least 1,000 times less than that required for I-GnRH-III. In 4-day monolayer cultured cells, I-GnRH-III was similarly extremely weak in releasing either LH or FSH, and, in fact, it released LH at a lower concentration (10–7M) than that required for FSH release (10–6M). In this assay, m-LHRH released both FSH and LH significantly at the lowest concentration tested (10–10M). On the other hand, I-GnRH-III had a high potency to selectively release FSH and not LH from hemipituitaries of male rats. The results suggest that the cultured cells were devoid of FSHRF receptors, thereby resulting in a pattern of FSH and LH release caused by the LHRH receptor. On the other hand, the putative FSH-releasing factor receptor accounts for the selective FSH release by I-GnRH-III when tested on hemipituitaries. Removal of calcium from the medium plus the addition of EGTA, a calcium chelator, suppressed the release of gonadotropins induced by either I-GnRH-III or LHRH, indicating that calcium is required for the action of either peptide. Previous results showed that sodium nitroprusside, a releaser of nitric oxide (NO), causes the release of both FSH and LH from hemipituitaries incubated in vitro. In the present experiments, a competitive inhibitor of NO synthase, L-NG-monomethyl-l-arginine (300 μM) blocked the action of I-GnRH-III or partially purified FSHRF. The results indicate that I-GnRH-III and FSHRF act on putative FSHRF receptors by a calcium-dependent NO pathway.
Age-Dependent Replication of Respiratory Syncytial Virus in the Cotton Rat
Authors: Curtis Spencer J. , Ottolini Martin G. , Porter David D. , Prince Gregory A.
Published: July 2017

Despite the documented disease burden of respiratory syncytial virus (RSV) in the elderly, little is known about the underlying risk factors or pathogenesis of RSV in a geriatric population. This report describes an age-dependent change of RSV clearance in the lung and nose of the cotton rat. Six days postinfection with RSV, lung and nose viral titers were significantly higher in all older age groups as compared with 4- to 6-week old cotton rats (P < 0.05). When comparing the 4- to 6-week old animals to the 15- to 16-month old animals 6 days postinfection, there was over an 800- and 100-fold increase in lung and nose viral titers, respectively. The cotton rat may prove to be a useful model in eliciting mechanisms of severe RSV disease in the elderly.