The effect of negative air ions on the respiratory organs and blood

The effect of ionized air containing negatively charged ions at a concentration of 320000–350000 ions/cm³ inhaled by rats was studied. It was demonstrated that the inhalation of negative air ions for 60 min activated the secretion of goblet cells without impairing the tracheal mucosa and changing the protein profile of bronchoalveolar lavage. It was also found that the level of spontaneous production of reactive oxygen species by unfractionated blood cells increased after the action of negative air ions in both males and females. However, the intensity of their generation induced by opsonized zymosan increased only in females. Different sensitivities of the female and male blood antioxidant enzymes—superoxide dismutase and glutathione reductase—to negative air ions were observed. These results allow the effect of negative air ions on the respiratory organs and blood to be interpreted as priming and weak activation via a direct action on the mucosa of primary target respiratory organs and then on the blood.     

A Beneficiary Role for Neuraminidase in Influenza Virus Penetration through the Respiratory Mucus

Swine influenza virus (SIV) has a strong tropism for pig respiratory mucosa, which consists of a mucus layer, epithelium, basement membrane and lamina propria. Sialic acids present on the epithelial surface have long been considered to be determinants of influenza virus tropism. However, mucus which is also rich in sialic acids may serve as the first barrier of selection. It was investigated how influenza virus interacts with the mucus to infect epithelial cells. Two techniques were applied to track SIV H1N1 in porcine mucus. The microscopic diffusion of SIV particles in the mucus was analyzed by single particle tracking (SPT), and the macroscopic penetration of SIV through mucus was studied by a virus in-capsule-mucus penetration system, followed by visualizing the translocation of the virions with time by immunofluorescence staining. Furthermore, the effects of neuraminidase on SIV getting through or binding to the mucus were studied by using zanamivir, a neuraminidase inhibitor (NAI), and Arthrobacter ureafaciens neuraminidase. The distribution of the diffusion coefficient shows that 70% of SIV particles were entrapped, while the rest diffused freely in the mucus. Additionally, SIV penetrated the porcine mucus with time, reaching a depth of 65 µm at 30 min post virus addition, 2 fold of that at 2 min. Both the microscopic diffusion and macroscopic penetration were largely diminished by NAI, while were clearly increased by the effect of exogenous neuraminidase. Moreover, the exogenous neuraminidase sufficiently prevented the binding of SIV to mucus which was reversely enhanced by effect of NAI. These findings clearly show that the neuraminidase helps SIV move through the mucus, which is important for the virus to reach and infect epithelial cells and eventually become shed into the lumen of the respiratory tract.     

Generation of Negative Air Ions by Plants upon Pulsed Electrical Stimulation Applied to Soil

Generation of negative air ions (NAI) by pot plants (aloe Aloe arborescens, haworthia Haworthia rasalata, echinopsis Echinopsis tubiflora, mammillaria Mammillaria prolifera, opuntia Opuntia brunnescens, spider plant Chlorophytum comosum, and jade plant Crassula portulacea) was studied when high-voltage pulses were applied to soil. Plants that generated low amounts of NAI (such as jade plant and echinopsis) elevated NAI level 2–3 times over the mean background level. Plants that produced moderate amounts of NAI (haworthia, opuntia, and mammillaria) increased the NAI level hundredfold, whereas highly active plants (aloe and spider plant) increased the NAI level thousand times. Aloe plants can maintain constant NAI concentration in the ambient air (125 ± 15 × 10³ ions/cm³) for a long time (7–8 h). Negative air ions were predominantly generated by the leaf tips. The capacity of aloe to produce NAI considerably reduced with plant age and was lost, although reversibly, at temperatures below 8.5°C. The rate of NAI generation considerably depended on weather conditions. It was demonstrated that superoxide anion radical is one of NAI species generated by plants.     

Effects of negative air ions on activity of neural substrates involved in autonomic regulation in rats

The neural mechanism by which negative air ions (NAI) mediate the regulation of autonomic nervous system activity is still unknown. We examined the effects of NAI on physiological responses, such as blood pressure (BP), heart rate (HR), and heart rate variability (HRV) as well as neuronal activity, in the paraventricular nucleus of the hypothalamus (PVN), locus coeruleus (LC), nucleus ambiguus (NA), and nucleus of the solitary tract (NTS) with c-Fos immunohistochemistry in anesthetized, spontaneously breathing rats. In addition, we performed cervical vagotomy to reveal the afferent pathway involved in mediating the effects of NAI on autonomic regulation. NAI significantly decreased BP and HR, and increased HF power of the HRV spectrum. Significant decreases in c-Fos positive nuclei in the PVN and LC, and enhancement of c-Fos expression in the NA and NTS were induced by NAI. After vagotomy, these physiological and neuronal responses to NAI were not observed. These findings suggest that NAI can modulate autonomic regulation through inhibition of neuronal activity in PVN and LC as well as activation of NA neurons, and that these effects of NAI might be mediated via the vagus nerves.     

Reactive oxygen species and melanoma: an explanation for gender differences in survival?

Epidemiological research consistently shows a female advantage in melanoma survival. So far, no definite candidate for the explanation of this phenomenon has emerged. We propose that gender differences in oxidative stress caused by radical oxygen species (ROS) underlie these survival differences. It is known that males express lower amounts of anti-oxidant enzymes, resulting in more oxidative stress than females. The primary melanoma environment is characterized by high ROS levels, from exogenous sources as well as ROS production within melanoma cells themselves. ROS are known to be able to promote metastasis through a wide variety of mechanisms. We hypothesize that the higher levels of ROS in men enhance selection of ROS-resistance in melanoma cells. Subsequently, ROS can stimulate the metastatic potential of melanoma cells. In addition, due to the lower anti-oxidant defenses in men, ROS produced by melanoma cells cause more damage to healthy tissues surrounding the tumor, further stimulating metastasis. Therefore, ROS may explain the observed differences between males and females in melanoma survival.     

Oxidative modification of ferritin induced by methylglyoxal

Methylglyoxal (MG) was identified as an intermediate in non-enzymatic glycation and increased levels were reported in patients with diabetes. In this study, we evaluated the effects of MG on the modification of ferritin. When ferritin was incubated with MG, covalent crosslinking of the protein increased in a time- and MG dose-dependent manner. Reactive oxygen species (ROS) scavengers, N-acetyl-(L)-cysteine and thiourea suppressed the MG-mediated ferritin modification. The formation of dityrosine was observed in MG-mediated ferritin aggregates and ROS scavengers inhibited the formation of dityrosine. During the reaction between ferritin and MG, the generation of ROS was increased as a function of incubation time. These results suggest that ROS may play a role in the modification of ferritin by MG. The reaction between ferritin and MG led to the release of iron ions from the protein. Ferritin exposure to MG resulted in a loss of arginine, histidine and lysine residues. It was assumed that oxidative damage to ferritin caused by MG may induce an increase in the iron content in cells, which is deleterious to cells. This mechanism, in part, may provide an explanation or the deterioration of organs under diabetic conditions. [BMB reports 2012; 45(3): 147-152].     

Interaction of ozone and negative air ions to control micro-organisms

AIMS: The aims of this study were to investigate the effect of ozone and/or negative air ions (NAI) on the viability of bacteria. METHODS AND RESULTS: Dilute cell suspensions of Pseudomonas fluorescens, Erwinia carotovora pv. carotovora and Escherichia coli were inoculated onto agar and subsequently exposed to ozone and/or NAI. Ozone concentration was maintained at 100 +/- 5 nl l-1 and NAI at 106 ml-1. When exposed to a combination of ozone and NAI, viability among all three bacterial species decreased more rapidly when they were inoculated onto potato dextrose agar (PDA) than onto nutrient agar (NA). A subsequent test examined the effect of ozone and NAI alone or in combination on the bacteria inoculated onto PDA only. Treatment with NAI alone had no killing effect on any of the bacterial species. However, a strong interaction between ozone and NAI was observed. Pseudomonas fluorescens was most susceptible to the combined treatment. Cell viability was reduced to 0.7% after 6 h, while 76% of the cells remained viable when exposed to ozone alone. Viability of Erwinia carotovora pv. carotovora was reduced to 4% after 6 h in the combined treatment compared with 69% when exposed to ozone alone. Escherichia coli was relatively more resistant to the combined treatment; viability was reduced to 40% after 11 h compared with 70% in the ozone alone treatment. CONCLUSIONS: A strong synergism between ozone and NAI on bacterial cell death was found, but the degree of this effect varied depending on bacterial species. SIGNIFICANCE AND IMPACT OF THE STUDY: The synergism of ozone with NAI may provide an effective method of reducing food-borne disease and decay of fresh produce.     

Crosstalk between platelet-derived growth factor-induced Nox4 activation and MUC8 gene overexpression in human airway epithelial cells

Reactive oxygen species (ROS) contribute to chronic airway inflammation, and NADPH oxidase (Nox) is an important source of ROS. However, little is known of the role that ROS play in chronic upper respiratory tract inflammation. We investigated the mechanism of ROS generation and its association with mucin gene overexpression in the nasal epithelium. The level of platelet-derived growth factor (PDGF) expression was increased in sinusitis mucosa, and high-level PDGF expression induced intracellular ROS, followed by MUC8 gene overexpression in normal human nasal epithelial cells. Knockdown of Nox4 expression with Nox4 siRNA decreased PDGF-induced intracellular ROS and MUC8 expression. Infection with an adenovirus containing Nox4 cDNA resulted in Nox4 overexpression and increased intracellular levels of ROS and MUC8 expression. PDGF and Nox4 overexpression are essential components of intracellular ROS generation and may contribute to chronic inflammation in the nasal epithelium through induction of MUC8 overexpression.     

Gender differences in murine airway responsiveness and lipopolysaccharide-induced inflammation

The roles of gender and sex hormones in lung function and disease are complex and not completely understood. The present study examined the influence of gender on lung function and respiratory mechanics in naive mice and on acute airway inflammation and hyperresponsiveness induced by intratracheal LPS administration. Basal lung function characteristics did not differ between naive males and females, but males demonstrated significantly greater airway responsiveness than females following aerosolized methacholine challenge as evidenced by increased respiratory system resistance and elastance (p < 0.05). Following LPS administration, males developed more severe hypothermia and greater airway hyperresponsiveness than females (p < 0.05). Inflammatory indices including bronchoalveolar lavage fluid total cells, neutrophils, and TNF-alpha content were greater in males than in females 6 h following LPS administration (p < 0.05), whereas whole-lung TLR-4 protein levels did not differ among treatment groups, suggesting that differential expression of TLR-4 before or after LPS exposure did not underlie the observed inflammatory outcomes. Gonadectomy decreased airway inflammation in males but did not alter inflammation in females, whereas administration of exogenous testosterone to intact females increased their inflammatory responses to levels observed in intact males. LPS-induced airway hyperresponsiveness was also decreased in castrated males and was increased in females administered exogenous testosterone. Collectively, these data indicate that airway responsiveness in naive mice is influenced by gender, and that male mice have exaggerated airway inflammatory and functional responses to LPS compared with females. These gender differences are mediated, at least in part, by effects of androgens.     

Sex‐ And tissue‐specific differences in telomere length in a reptile

The usage of telomere length (TL) in blood as a proxy for the TL of other tissues relies on the assumption that telomere dynamics across all tissues are similar. However, telomere attrition can be caused by reactive oxygen species (ROS) which may vary with metabolic rate, which itself varies across organs depending upon the life history strategy of an organism. Thus, we chose to measure the telomeres of various cell types in juvenile painted dragon lizards, Ctenophorus pictus, given their unusual life history strategy. Individuals typically only experience a single mating season. We measured the TL of male and female dragons using qPCR and observed that TL varied with tissue type and sex. Telomeres of blood cells were longer than those of liver, heart, brain, and spleen, and females had longer telomeres than males. Brain telomeres in males were approximately half the length of those in females. Telomeric attrition in the male brain may be due to the need for rapid learning of reproductive tactics (territory patrol and defense, mate‐finding). Significant correlations between the TL of tissue types suggest that blood TL may be a useful proxy for the TL of other tissues. Our comparison of organ‐specific telomere dynamics, the first in a reptile, suggests that the usage of blood TL as a proxy requires careful consideration of the life history strategy of the organism.     

Gender effect on in vitro lymphocyte subset levels of healthy individuals

Differences in gender immune response have resulted in differences in immune protection and susceptibility to inflammatory diseases. Cultured peripheral blood mononuclear cells (PBMC) are widely used in immunomodulation studies, yet the influence of gender is usually not considered. We examined the effect of in vitro culture and phytohaemagglutinin (PHA) stimulation on PBMC lymphocyte subsets using flowcytometry. Full blood counts of whole blood showed higher levels of lymphocyte in male subjects. Lymphocyte subsets enumeration revealed higher NK cell counts in males and higher B cells in females. Cultured PBMC resulted in significant increases in B and total T cell percentages among females and NK cells among males. PHA stimulated significantly increased percentages of NK and total T cells in males and total activated T cells (CD69+) in females. Our results showed significant gender differences in lymphocyte subsets in cultured conditions. This may affect experimental outcome.     

Measuring neutrophil functions might be a good predictive marker of overtraining in athletes

In order to develop a predictive marker of overtraining in athletes, we examined the changes in neutrophil function [reactive oxygen species (ROS) production capability and phagocytic activity (PA)] for 10 male and 13 female judoists attending a training camp. Measurements were taken four times in total—immediately before and after a 2 h unified exercise loading (UEL) performed 1 day before (Pre‐Camp) and the day after the 7 day training camp (Post‐Camp). UEL‐mediated aspartate aminotransferase was higher at Post‐Camp than at Pre‐Camp in females but not in males. Post‐Camp leukocyte/neutrophil counts after the UEL significantly increased in females but not in males. The rate of change in C4 was significantly smaller in females than in males at Post‐Camp. Only ROS significantly decreased without any compensation (increase in PA) being made at Post‐Camp in females. In conclusion, this finding, namely that ROS significantly decreased only at Post‐Camp without any compensatory mechanism (increase in PA), would suggest that the training camp imposed greater loading on females than males. This consideration was supported by the atypical aspartate aminotransferase, leukocyte/neutrophil counts and C4 findings which were seen at Post‐Camp only in females. Therefore, regularly examining neutrophil functions such as ROS and PA might be a good preventative measure against overtraining in athletes participating in training camps. Copyright © 2008 John Wiley & Sons, Ltd.     

Mitochondria in exercise-induced oxidative stress

In recent years it has been suggested that reactive oxygen species (ROS) are involved in the damage to muscle and other tissues induced by acute exercise. Despite the small availability of direct evidence for ROS production during exercise, there is an abundance of literature providing indirect support that oxidative stress occurs during exercise. The electron transport associated with the mitochondrial respiratory chain is considered the major process leading to ROS production at rest and during exercise. It is widely assumed that during exercise the increased electron flow through the mitochondrial electron transport chain leads to an increased rate of ROS production. On the other hand, results obtained by in vitro experiments indicate that mitochondrial ROS production is lower in state 3 (ADP-stimulated) than in state 4 (basal) respiration. It is possible, however, that factors, such as temperature, that are modified in vivo during intense physical activity induce changes (uncoupling associated with loss of cytochrome oxidase activity) leading to increased ROS production. The mitochondrial respiratory chain could also be a potential source of ROS in tissues, such as liver, kidney and nonworking muscles, that during exercise undergo partial ischemia because of reduced blood supply. Sufficient oxygen is available to interact with the increasingly reduced respiratory chain and enhance the ROS generation. At the cessation of exercise, blood flow to hypoxic tissues resumes leading to their reoxygenation. This mimics the ischemia-reperfusion phenomenon, which is known to cause excessive production of free radicals. Apart from a theoretical rise in ROS, there is little evidence that exercise-induced oxidative stress is due to its increased mitochondrial generation. On the other hand, if mitochondrial production of ROS supplies a remarkable contribution to exercise-induced oxidative stress, mitochondria should be a primary target of oxidative damage. Unfortunately, there are controversial reports concerning the exercise effects on structural and functional characteristics of mitochondria. However, the isolation of mitochondrial fractions by differential centrifugation has shown that the amount of damaged mitochondria, recovered in the lightest fraction, is remarkably increased by long-lasting exercise.     

种群密度效应对成年东方田鼠内脏器官的影响

为了研究种群密度对东方田鼠(Microtus fortis)内脏器官(心、肺、肝、脾、肾、肾上腺)的影响,随机选取稳定的同性别饲养群的成年东方田鼠258只,雌雄各半,分A组30笼:2只/笼,B组15笼:4只/笼,C组11笼:6只/笼和D组9笼:8只/笼共4个密度组,饲养90d后解剖,取内脏器官,称重以及测定血浆皮质醇浓度并进行比较。结果表明:在相同密度内,除B组孕鼠的肝脏重较未孕鼠有极显著差异外,其它各组(A、C、D)怀孕鼠和未孕鼠的各内脏器官重均无显著差异。在不同密度间,怀孕鼠的肝脏重有极显著差异,孕鼠与未孕鼠的其余各内脏器官均无显著差异;雄鼠的肺重、脾脏重和雌鼠的脾脏重、肾上腺重差异显著,其余各器官重在不同密度间虽未表现出显著差异,但均具有随着密度增加而器官重量逐渐增大的趋势。各个密度组中的雄性个体血浆皮质醇浓度分别显著高于雌性,且差异显著;同一性别比较,不同密度间的雌性个体血浆皮质醇浓度差异不显著,而雄性个体血浆皮质醇浓度差异则显著,随密度增大而明显增加。可见高密度压力导致内脏器官重量上有所调节,但不同脏器受密度因素影响程度不同。     

A new method to study changes in microvascular blood volume in muscle and adipose tissue: real-time imaging in humans and rat

We employed and evaluated a new application of contrast-enhanced ultrasound for real-time imaging of changes in microvascular blood volume (MBV) in tissues in females, males, and rat. Continuous real-time imaging was performed using contrast-enhanced ultrasound to quantify infused gas-filled microbubbles in the microcirculation. It was necessary to infuse microbubbles for a minimum of 5-7 min to obtain steady-state bubble concentration, a prerequisite for making comparisons between different physiological states. Insulin clamped at a submaximal concentration (～75 μU/ml) increased MBV by 27 and 39% in females and males, respectively, and by 30% in female subcutaneous adipose tissue. There was no difference in the ability of insulin to increase muscle MBV in females and males, and microvascular perfusion rate was not increased significantly by insulin. However, perfusion rate of the microvascular space was higher in females compared with males. In rats, insulin clamped at a maximal concentration increased muscle MBV by 60%. Large increases in microvascular volume and perfusion rate were detected during electrical stimulation of muscle in rats and immediately after exercise in humans. We have demonstrated that real-time imaging of changes in MBV is possible in human and rat muscle and in subcutaneous adipose tissue and that the method is sensitive enough to pick up relatively small changes in MBV when performed with due consideration of steady-state microbubble concentration. Because of real-time imaging, the method has wide applications for determining MBV in different organs during various physiological or pathophysiological conditions.     

Trichosomoides nasalis (Nematoda: Trichinelloidea) in the murid host Arvicanthis niloticus: Migration to the epithelium of the nasal mucosa after intramuscular development

Knowledge of the biology of the trichinelloid subfamily Trichosomoidinae is poor. Trichosomoides nasalis is a common parasite of Arvicanthis niloticus (Muridae) in Senegal, and a procedure for experimental infections has been established. It has been demonstrated that larvae develop in striated muscle fibres, similar to Trichinella spp., but they are not arrested in the first stage, and they reach the adult stage within three weeks. In the present histological study it is shown that T. nasalis females and dwarf males migrate from the abdomen and thorax to the host’s muzzle, moving through connective tissues and between muscles. A few migrating specimens were also found in the blood vessels of the nasal mucosa. While sexes were still separated in the lamina propria of the mucosa, females recovered from the epithelium contained intra-uterine males. Worms were found between the incisors in the mucosa of the anterior and median conchae which are rich in mucous cells. Only the pseudostratified epithelium was parasitized. Under natural conditions, the inflammation of the nasal mucosa that is induced by the parasites might reduce the competitiveness of infected rodents when foraging or looking for potential mates.     

Lactotroph hyperplasia in the pituitaries of female mice expressing high levels of bovine growth hormone

PEPCK/bGH transgenic mice have very high blood levels of foreign GH, and prominent reproductive disturbances, especially in females. To obtain a deeper insight into the causes of these abnormalities, pituitaries of PEPCK/bGH transgenics were studied by immunocytochemistry, electron microscopy and in situ hybridization (ISH) techniques. Pituitary weights were significantly reduced (P < 0.05) in transgenic males, while in transgenic females they were increased without reaching significance compared to nontransgenic controls. In both sexes, GH cells were inhibited, as previously described in other lines of GH transgenic mice. In females, PRL cells were increased by 37% compared to controls. Ultrastructurally, the lactotrophs had characteristics of stimulation and PRL mRNA was increased by 35%. In males the increase in the number of PRL immunoreactive cells was not significant, the PRL mRNA signal did not differ from controls, and there were no changes in their ultrastructure. Only in females ACTH cells were significantly reduced (P < 0.05) in number and unchanged in males; however, POMC mRNA signal was increased in both genders and reached significance (P < 0.05) in males. In females, but not in males, the percentage of LH cells was lower than in control mice. In conclusion, the high blood bGH levels induced sex related changes in transgenic mice from the present line. The infertility of PEPCK/bGH transgenic females may be attributed to lactotroph hyperplasia and marked reduction in number of gonadotrophs.     

Dynamic measure of production rate of cortisol in the mature guinea-pig in response to the stress of anesthesia: Effect of estradiol

The effect of estradiol on adrenal secretion rate of cortisol in response to a stress induced by anesthesia, was examined by comparing the metabolic clearance rate and the production rate of cortisol between males and females and after estradiol administration in castrated animals. Metabolic clearance rates of cortisol (MCR) were significantly higher (+30%) in males than in females. Castration lowered the MCR of cortisol in males and had no significant effect in females. After estradiol administration, a fall in the MCR of cortisol concomitant with a rise in blood cortisol level was observed especially in males in which the effect of treatment was more marked than in females and highly significant. The production rate of cortisol was identical in males and females and was slightly increased in estradiol-treated males and females. The data indicate that estradiol had an inhibitory effect on metabolic clearance of cortisol, which caused an important rise of blood cortisol levels in response to stress and which prevented an increase in the adrenal response to the stress. Since the pituitary adrenal cortex can respond in a normal way to stress, the low value of MCR of cortisol could be the limiting factor in the adrenal secretion rate of cortisol in estrogen-treated guinea-pigs.     

Variations in sexual dimorphism in the skulls of rats subjected to malnutrition, castration, and treatment with gonadal hormones

Two groups of weanling rats were subjected to malnutrition, one with periodic injections of testosterone (males) and the other with estradiol (females). Two other groups (castrated males or castrated females) received normal feedings. In control animals, the relative weights (mg/gm body weight) of testes, seminal vesicles, and ovaries were greater than in malnourished rats. However, relative weights of those organs in hormone-treated, malnourished animals were greater than in those subjected to malnutrition alone and still greater than in controls. Normal sexual cranial dimorphism (SCD) was decreased 16% by male castration, 23% by malnutrition, and 83% by estradiol treatment in malnourished females. On the other hand, normal SCD was increased 20% by female castration and more than 200% by testosterone treatment in malnourished males. All monosexual comparisons corroborated the bisexual range of distances found. Testicular but not ovarian secretions seemed to influence sexual cranial dimorphism. Malnutrition delayed SCD because of a deficiency of testosterone level in stressed males. It is suggested that estradiol in females may counteract sexual cranial development and that its inhibitory effect may be additive to the testosterone deficit evoked by malnutrition.     

Sex-dependent differences in aged rat brain mitochondrial function and oxidative stress

Females show lower incidences of several neurodegenerative diseases related to oxidative stress and mitochondrial dysfunction than males. In addition, female rats show more differentiated mitochondria than males in several tissues. The aim of this work was to investigate the existence of sex-dependent differences in brain mitochondrial bioenergetics and oxidative balance in aged rats. Results showed that aged female rat brain had a lower mitochondria content than aged male brain but with a greater differentiation degree given the higher mitochondrial protein content and mitochondrial complex activities in females. Female rat brain also showed a better oxidative balance than that of males, reflected by the fact that higher mitochondrial respiratory chain function is accompanied by a similar ROS production and greater antioxidant enzyme activities, which could be responsible for the lesser oxidative damage observed in proteins and lipids in this sex. Interestingly, levels of UCP4 and UCP5--proteins related to a decrease in ROS production--were also higher in females. In conclusion, aged female rat brain had more differentiated mitochondria than male brain and showed a better control of oxidative stress balance, which could be due, in part, to the neuroprotective effect of UCPs.