Procyanidins and sensory nutrition; do procyanidins modulate homeostasis via astringent taste receptors?

Long-term intake of procyanidins has been suggested to reduce the risk of cardiovascular disease, dementia, and sensory function decline associated with aging. However, most of the ingested procyanidins are not absorbed and are excreted in the feces, so the mechanism of their beneficial impact is unknown. Procyanidins are the components of astringency in plant foods and their stimulation appears to be directly transmitted to the central nervous system via sensory nerves. Recent attention has been focused on the taste receptors expressed in the extra-oral gastrointestinal tract may regulate homeostasis via the neuroendocrine system. In this paper, we have reviewed recent findings on the relationship between the astringency of procyanidins and their bioregulatory effects.

Sensory Nutrition and Bitterness and Astringency of Polyphenols

Recent studies have demonstrated that the interaction of dietary constituents with taste and olfactory receptors and nociceptors expressed in the oral cavity, nasal cavity and gastrointestinal tract regulate homeostasis through activation of the neuroendocrine system. Polyphenols, of which 8000 have been identified to date, represent the greatest diversity of secondary metabolites in plants, most of which are bitter and some of them astringent. Epidemiological studies have shown that polyphenol intake contributes to maintaining and improving cardiovascular, cognitive and sensory health. However, because polyphenols have very low bioavailability, the mechanisms of their beneficial effects are unknown. In this review, we focused on the taste of polyphenols from the perspective of sensory nutrition, summarized the results of previous studies on their relationship with bioregulation and discussed their future potential.

Exploring Novel Vitamin K Derivatives with Anti-SARS-CoV-2 Activity

From our compound library of vitamin K derivatives, we found that some compounds exhibited anti-SARS-CoV-2 activity in VeroE6/TMPRSS2 cells. The common structure of these compounds was menaquinone-2 (MK-2) with either the m-methylphenyl or the 1-naphthyl group introduced at the end of the side chain. Therefore, new vitamin K derivatives having more potent anti-SARS-CoV-2 activity were explored by introducing various functional groups at the ω-position of the side chain. MK-2 derivatives with a purine moiety showed the most potent antiviral activity among the derivatives. We also found that their mechanism of action was the inhibition of RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2. The chemical structures of our compounds were completely different from those of nucleic acid derivatives such as remdesivir and molnupiravir, clinically approved RdRp inhibitors for COVID-19 treatment, suggesting that our compounds may be effective against viruses resistant to these nucleic acid derivatives.

Cinnamtannin A2, (-)-epicatechin tetramer, attenuates skeletal muscle wasting in disuse atrophy model mice induced by hindlimb suspension

The impact of repeated administration of cinntamtannin A2 (A2, 25 μg/kg) on skeletal muscle disuse atrophy model mice induced by hindlimb suspension for 14 days was examined. In soleus, weight loss and a reduction in the average myofibre size with shifting to the smaller side of the peak were observed in the suspension-vehicle group, but A2 reduced these changes. Average myofibre size significantly increased in ground-A2 compared to ground-vehicle. A marked increase in the dephosphorylation of forkhead box O (FoxO) 3a by the suspension was reduced by A2. The phosphorylation of protein kinase B (Akt) and eukaryotic translation initiation factor 4E-binding protein (4EBP)-1 were significantly increased by the treatment of A2. In addition, a single dose of A2 increased dramatically in the 24-h excretion of catecholamines in urine. These results suggest that A2 administration results in sympathetic nerve activation and promotes hypertrophy while inhibiting the progress of disuse muscle atrophy.

Activation of transient receptor potential channels is involved in reactive oxygen species (ROS)-dependent regulation of blood flow by (-)-epicatechin tetramer cinnamtannin A2

Intervention trials confirmed that blood flow-mediated dilatation increases significantly after intake of astringent (-)-epicatechin (EC) oligomers (procyanidins)-rich foods, but the mechanism remains unclear. We have previously found that procyanidins can activate the sympathetic nervous and subsequently increase blood flow. Here, we examined whether procyanidin-derived reactive oxygen species (ROS) activate transient receptor potential (TRP) channels in gastrointestinal sensory nerves and consequently induce sympathoexcitation. We evaluated the redox properties of EC and its tetramer cinntamtannin A2 (A2) at pH 5 or 7, mimicking plant vacuole or oral cavity/small intestine using a luminescent probe. At pH 5, A2 or EC showed O₂^･- scavenging ability, but they promoted O₂^･- generation at pH 7. We observed blood flow in rat cremaster arterioles using laser Doppler, a single oral dose of 10 µg/kg A2 markedly increased blood flow, while EC showed little activity. This change with A2 was significantly dampened by co-administration of adrenaline blocker, ROS scavenger N-acetyl-L-cysteine (NAC), TRP vanilloid 1, or ankyrin 1 antagonist. We also performed a docking simulation of EC or A2 with the binding site of a typical ligand for each TRP channel and calculated the respective binding affinities. The binding energies were notably higher for A2 than typical ligands, suggesting that A2 is less likely to bind to these sites. ROS produced at neutral pH following the orally administered A2 to the gastrointestinal tract could activate TRP channels, triggering sympathetic hyperactivation and causing hemodynamic changes.

Difference in endocrine and behavior between short-term single- and paired-housing mice in metabolic cage

Metabolic cage housing which is exposed to a number of environmental stressors is often used in pharmacokinetic studies. In this study, we compared the difference in stress response between single- and paired-housing in metabolic cages by evaluating the alteration of urinary stress hormones and behavior. Mice were randomly divided into single- or paired-housing groups and placed in a metabolic cage with wire mesh. Their urine was collected every 24 hours for consecutive 4 days to determine excreted catecholamine and corticosterone. The change in body weight was significantly decreased at 3 and 4 days in the single-housing group compared with that before the experiment, but not paired-housing group. The level of urinary catecholamines, such as noradrenaline, adrenaline, and their metabolite vanillylmandelic acid, was significantly increased in the single-housing compared with paired housing group and urinary corticosterone increased as well. Next, for the two similarly housed groups, we observed spontaneous behavior on the fourth day and conducted an elevated plus-maze test on the fifth day. Spontaneous behavior was not different between experimental groups. In the elevated plus-maze test, the proportion of time spent in the open arms was significantly prolonged in the paired-housing group compared to that of the single-housing group. Short-term social isolation stress loading in metabolic cages was suggested to exhibit endocrinological and behavioral changes in mice. To reduce such interference due to stress exposure, it was suggested to keep two mice in a metabolic cage.

Impact of cyanidin 3-O-glucoside on rat micro-and systemic circulation, possibly thorough angiogenesis

Cyanidin 3-O-glucoside (C3G), an antioxidant, is one of the most abundant anthocyanin in plant foods. Intervention trials and subsequent meta-analyses have suggested that anthocyanins could reduce the risks of cardiovascular diseases. This study investigated hemodynamic alterations following a single intragastric dose of C3G by measuring blood flow in rat cremaster muscle arteriole for 60 min. Next, in excised aortas, we performed western blotting to measure the phosphorylation of Akt and endothelial nitric oxide synthase (eNOS). A single oral dose of C3G significantly increased blood flow soon after ingestion, and it was maintained throughout the experimental period. In addition, aortic Akt phosphorylation increased. Then, we examined the impact of repeated oral administrations of C3G for 14 days. The mean blood pressure was significantly reduced at 7 and 14 days after treatment, with a slight increase in aortic eNOS expression. Immunohistochemical analyses of the soleus showed that the level of CD31, an angiogenesis-marker protein, was significantly increased with C3G. These results suggested that an oral dose of C3G increased blood flow, which promoted angiogenesis within skeletal muscle, and consequently, blood pressure was reduced.

Hormetic response to B-type procyanidin ingestion involves stress-related neuromodulation via the gut-brain axis: Preclinical and clinical observations

B-type procyanidins, a series of catechin oligomers, are among the most ingested polyphenols in the human diet. Results of meta-analyses have suggested that intake of B-type procyanidins reduces cardiovascular disease risk. Another recent focus has been on the effects of B-type procyanidins on central nervous system (CNS) function. Although long-term B-type procyanidin ingestion is linked to health benefits, a single oral intake has been reported to cause physiological alterations in circulation, metabolism, and the CNS. Comprehensive analyses of previous reports indicate an optimal mid-range dose for the hemodynamic effects of B-type procyanidins, with null responses at lower or higher doses, suggesting hormesis. Indeed, polyphenols, including B-type procyanidins, elicit hormetic responses in vitro, but animal and clinical studies are limited. Hormesis of hemodynamic and metabolic responses to B-type procyanidins was recently confirmed in animal studies, however, and our work has linked these effects to the CNS. Here, we evaluate the hormetic response elicited by B-type procyanidins, recontextualizing the results of intervention trials. In addition, we discuss the possibility that this hormetic response to B-type procyanidins arises via CNS neurotransmitter receptors. We have verified the direction of future research for B-type procyanidins in this review.

Relationship between hemodynamic alteration and sympathetic nerve activation following a single oral dose of cinnamtannin A2

We previously found that a single dose of B-type procyanidin mixture increase in skeletal muscle blood flow (BF). We compared BF changes following administration of (-)-epicatechin (EC, monomer) and the B-type procyanidins procyanidin B2 (B2, dimer), procyanidin C1 (C1, trimer), and cinnamtannin A2 (A2, tetramer). Each chemical was administered orally to rats, followed by BF measurement in cremaster arteriole for 60 min. About 10 and 100 µg/kg of B2 and C1 elicited BF increase, the effect was potent at 100 µg/kg. BF also increased significantly after administration of 10 µg/kg A2, but not with the administration at 100 µg/kg. EC yielded no BF changes. Co-treatment with the nonselective adrenaline blocker carvedilol attenuated the BF increase seen with 10 µg/kg A2 treatment. This outcome suggested the involvement of sympathetic nerve activation in the BF increase by this dose of A2. Co-treatment of 100 µg/kg A2 with the α2 blocker yohimbine exhibited an increase of BF significantly. The α2 adrenaline receptor in the vasomotor centre is an inhibitory receptor and it regulates hemodynamics. This result suggested that high doses of A2 did not alter BF because of activating the α2 adrenergic receptor. Phosphorylation of aortic endothelial nitric oxide synthase (eNOS) increased with 10 µg/kg A2 alone or co-treatment with 100 µg/kg A2 and yohimbine, but not with co-treatment of 10 µg/kg A2 and carvedilol or 100 µg/kg A2 alone. These results imply that A2 does not directly activate eNOS, but that shear stress from the increased BF might be associated with eNOS phosphorylation.

Method for detecting hemodynamic alterations following a single gavage in rats

It is known that administering a gavage to rodents evokes a cardiac reflex, due to gastrointestinal stimulation. Consequently, it is difficult to evaluate changes in hemodynamics after a single oral dose of a pungent or astringent, which alters the circulation by increasing sympathetic activity. In the present study, we developed a method for administering a gavage without significantly affecting hemodynamics measurements. We marked a gastric tube at 10 cm from the tip, to mark the distance from the oral cavity to the stomach body of Wistar male rats. Rats were intubated under urethane anesthesia.After 10–15 min of stabilization, we measured the mean blood pressure (MBP), heart rate (HR), and blood flow (BF) in the cremaster arteriole under two different conditions; condition 1: a pointed gastric tube, room temperature distilled water, and injected at normal speed (approximately 3 ml/min); condition 2: a rounded gastric tube, 37°C distilled water, and injection at 1.0 ml/min. Under condition 1, we observed striking hemodynamic alterations, due to the somatic afferent reflex. In contrast, under condition 2, these hemodynamic changes were nearly eliminated. In addition, we could clearly detect hemodynamic changes in rats after a single gavage treatment of pungent (capsaicin) or astringent (cinnamtannin A2). We observed transient increases in the HR and MBP soon after treatment with capsaicin. Moreover, cremasteric BF was elevated with cinnamtannin A2. These results confirmed the utility of the gavage method developed in this study.

Theaflavins decrease skeletal muscle wasting in disuse atrophy induced by hindlimb suspension in mice

We previously found that a single dose of theaflavins induced skeletal muscle metabolic changes. In this study, we examined the effect of theaflavins on disuse muscle atrophy model mice by hindlimb suspension. Mice were assigned to 4 groups; ground-vehicle, ground-theaflavins, suspension-vehicle, and suspension-theaflavins, dosed with theaflavins (250 mg/kg/day) for 2 weeks. The peak of myotube size of cross sectional area was significantly moved to the smaller side in the suspension-vehicle group compared with the ground-vehicle group, and these shifts were significantly reduced by the treatment with theaflavins in both soleus and extensor digitorum longus. The level of phosphorylated eukaryotic translation initiation factor 4E-binding protein (4EBP)-1, located downstream of the Akt/mTOR pathway, was significantly different between suspension-vehicle and suspension-theaflavins in soleus. The ratio of forkhead box O (FoxO) 3a to phosphorylated FoxO3a significantly increased in soleus or tended to rise in extensor digitorum longus of suspension-vehicle group compared with ground-vehicle. In contrast, these changes were not observed in suspension-theaflavins group. These results suggested that theaflavins inhibited the progress of disuse muscle atrophy through modulation of protein metabolism.

Acylated anthocyanins derived from purple carrot (Daucus carota L.) induce elevation of blood flow in rat cremaster arteriole

Acylated anthocyanins are more stable than monomeric anthocyanins, but little is known about their physiological effects.

Characterization of Bacillus subtilis strains in Thua nao, a traditional fermented soybean food in northern Thailand

AIMS

To clarify the diversity of Bacillus subtilis strains in Thua nao that produce high concentrations of products useful in food manufacturing and in health-promoting compounds.

METHOD AND RESULTS

Production of amylase, protease, subtilisin NAT (nattokinase), and gamma-polyglutamic acid (PGA) by the Bacillus subtilis strains in Thua nao was measured. Productivity of protease NAT by these strains tended to be higher than by Japanese commercial natto-producing strains. Molecular diversity of isolated strains was analysed via randomly amplified polymorphic DNA-PCR fingerprinting. The strains were divided into 19 types, including a type with the same pattern as a Japanese natto-producing strain.

CONCLUSION

B. subtilis strains that could be a resource for effective production of protease, amylase, subtilisin NAT, or PGA were evident in Thua nao produced in various regions in northern Thailand.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study clearly demonstrated the value of Thua nao as a potential resource of food-processing enzymes and health-promoting compounds.

The efficacy of acetic acid for glycogen repletion in rat skeletal muscle after exercise

We examined the effect of acetic acid, the main component of vinegar, on glycogen repletion by using swimming-exercised rats. Rats were trained for 7 days by swimming. After an overnight fast, they were subjected to a 2-hr swimming exercise. Immediately afterward, they were given by gavage 2 ml of one of the following solutions: 30 % glucose only or 30 % glucose with 0.4 % acetic acid. Rats were sacrificed by decapitation before, immediately after exercise and 2 hours after the feeding. Exercise significantly decreased soleus and gastrocnemius glycogen content, and feeding significantly increased liver, soleus and gastrocnemius glycogen content. In soleus muscle, acetate feeding significantly increased glycogen content and the ratio of glycogen synthase in the I form (means +/- SEM: 4.04 +/- 0.41 mg/g-tissue and 47.0 +/- 0.7 %, respectively) in contrast to no acetate feeding (3.04 +/- 0.29 mg/g-tissue and 38.1 +/- 3.4 %, respectively). Thus, these findings suggest that the feeding of glucose with acetic acid can more speedily accelerate glycogen repletion in skeletal muscle than can glucose only.

Screening for phenoloxidases from edible mushrooms

A screening test for phenoloxidases from edible mushrooms was done on potato dextrose agar plates that contained phenolic chemicals. Many edible mushrooms showed positive reactions on the agar plates. Among them, Auricularia auricula-judae, Clitocybe nebularis, Lentinus edodes, Pholiota aurivella, and Pseudohiatula oshimae produced a considerable amount of phenoloxidases, and these enzymes showed maximum activities in the acidic pH region.

Acetic acid feeding enhances glycogen repletion in liver and skeletal muscle of rats

To investigate the efficacy of the ingestion of vinegar in aiding recovery from fatigue, we examined the effect of dietary acetic acid, the main component of vinegar, on glycogen repletion in rats. Rats were allowed access to a commercial diet twice daily for 6 d. After 15 h of food deprivation, they were either killed immediately or given 2 g of a diet containing 0 (control), 0.1, 0.2 or 0.4 g acetic acid/100 g diet for 2 h. The 0.2 g acetic acid group had significantly greater liver and gastrocnemius muscle glycogen concentration than the control group (P < 0.05). The concentrations of citrate in this group in both the liver and skeletal muscles were >1.3-fold greater than in the control group (P > 0.1). In liver, the concentration of xylulose-5-phosphate in the control group was significantly higher than in the 0.2 and 0.4 g acetic acid groups (P < 0.01). In gastrocnemius muscle, the concentration of glucose-6-phosphate in the control group was significantly lower and the ratio of fructose-1,6-bisphosphate/fructose-6-phosphate was significantly higher than in the 0.2 g acetic acid group (P < 0.05). This ratio in the soleus muscle of the acetic acid fed groups was <0.8-fold that of the control group (P > 0.1). In liver, acetic acid may activate gluconeogenesis and inactivate glycolysis through inactivation of fructose-2,6-bisphosphate synthesis due to suppression of xylulose-5-phosphate accumulation. In skeletal muscle, acetic acid may inhibit glycolysis by suppression of phosphofructokinase-1 activity. We conclude that a diet containing acetic acid may enhance glycogen repletion in liver and skeletal muscle.

Secretion and gene expression of secretory leukocyte protease inhibitor by human airway submucosal glands

Submucosal glands were isolated within 4 h of death from tracheae and bronchi obtained from autopsied lungs, and the secretory response of secretory leukocyte protease inhibitor (SLPI) was examined with ELISA and a secretory index. Although human neutrophil elastase (HNE) at low concentrations increased SLPI secretion above the control level (i.e., 149% of control level at 10(-11) M), HNE at high concentrations significantly decreased it below the control level (i.e., 16% of control level at 10(-7) M). The decrease in SLPI concentration was shown to result from the degradation of SLPI by excessive HNE. Methacholine induced significant secretion (i.e., 363% of control level at 10(-5) M) that was abolished by both M(1) and M(3) receptor antagonists. A semiquantitative analysis of SLPI mRNA by RT-PCR and Southern blot showed that compared with the superficial epithelium, submucosal glands had a 30-fold or higher level of SLPI mRNA. Both HNE and methacholine significantly increased the level of SLPI mRNA in submucosal glands in a dose-dependent manner (i.e., 357% of control level at 10(-7) M and 175% of control level at 10(-5) M, respectively). These findings indicate that human airway submucosal glands can transcribe 30-fold or more SLPI mRNA than the superficial epithelium and that SLPI mRNA transcription and secretion are regulated by both HNE and muscarinic receptors.

Macrophage inflammatory protein 3alpha transgene attracts dendritic cells to established murine tumors and suppresses tumor growth

Dendritic cells (DCs) are powerful antigen-presenting cells that function as the principal activators of T cells. Since the human CC chemokine, macrophage inflammatory protein 3alpha (MIP-3alpha), is chemotactic for DCs in vitro, we hypothesized that adenovirus-mediated gene transfer of MIP-3alpha (AdMIP-3alpha) to tumors might induce local accumulation of DCs and inhibit growth of preexisting tumors. AdMIP-3alpha directed expression of mRNA and protein in vitro, and the supernatant of A549 cells infected with AdMIP-3alpha was chemotactic for DCs. In vivo, injection of AdMIP-3alpha into subcutaneous tumors resulted in local expression of the MIP-3alpha cDNA and in the local accumulation of DCs. In four syngeneic tumor models, growth of established tumors was significantly inhibited compared with untreated tumors or tumors injected with control vector, and in all but the poorly immunogenic LLC carcinoma model, this treatment increased survival advantage of the preexisting tumors. In all four tumor models, intratumoral injection of AdMIP-3alpha induced the local accumulation of CD8b. 2(+) cells and elicited tumor-specific cytotoxic T-lymphocyte activity, and adoptive transfer of splenocytes of animals receiving this treatment protected against a subsequent challenge with the identical tumor cells. In wild-type but not in CD8-deficient mice, AdMIP-3alpha inhibited the growth of tumors. Finally, AdMIP-3alpha also inhibited the growth of distant tumors. This strategy may be useful for enlisting the help of DCs to boost anti-tumor immunity against local and metastatic tumors without the necessity of ex vivo isolation and manipulation of DCs.

Verb generation in Japanese--A multicenter PET activation study

Cerebral blood flow (CBF) during silent verb generation was measured at four Japanese PET centers. To minimize the variance of the measurement, speakers of a single language (Japanese) served as subjects and experimental conditions at the four PET centers were controlled as much as possible. Two types of activation patterns were observed: activations in the left dorsolateral prefrontal cortices and the medial frontal cortex (at the two centers with a 2D PET scanner) and additional activation in the left posterior temporal cortex (at the two centers with a 3D scanner). This suggests either a difference in the sensitivity of the two types of PET scanners (viz., a 3D scanner is generally more sensitive than a 2D scanner) and/or subject bias due to the small number of subjects at the individual centers. The pooled activation pattern was fundamentally similar to activation patterns obtained in the previous studies for verb generation in English and other European languages, suggesting that regions for verb generation are independent of particular languages. Regions relevant to verb generation are discussed.

Surfactant protein A2 gene expression by human airway submucosal gland cells

To determine whether human airway submucosal glands produce and secrete surfactant proteins, we examined their protein and gene expression in submucosal glands from trachea and bronchi obtained from operated and autopsied lungs within 4 h of death. Using a monoclonal antibody (PE-10) against surfactant protein A (SP-A), a positive immunoperoxidase stain was observed over serous cells of submucosal glands in histologic sections of airway walls. Measurement of SP-A in culture medium samples using single-step enzyme-linked immunosorbent assay showed a significant secretion of SP-A by isolated submucosal glands (1.2 +/- 0.08 ng/ml/h, SEM, n = 40). In gene expression experiments by reverse transciption-polymerase chain reaction, the SP-A complementary DNA (cDNA) segment was amplified from isolated submucosal glands, indicating the presence of SP-A messenger RNA (mRNA) in airway submucosal glands. Bronchial superficial epithelial cells failed to show the presence of SP-A mRNA. No cDNA segment of SP-B, SP-C, or SP-D cDNA was amplified from isolated submucosal glands or superficial epithelial cells, whereas all were amplified from alveolar tissue. Furthermore, in contrast to the control alveolar tissue, which expressed both SP-A1 and SP-A2 genes, SP-A2 gene transcript alone was detected in isolated submucosal glands by Southern analysis that included the digestion of the amplified SP-A cDNA fragment with the restriction enzyme Apa I. These findings indicate that human airway submucosal gland cells can transcribe the SP-A2 gene and produce SP-A protein in a manner different from peripheral airways and alveoli, playing a role in the airway defense mechanism.

Dexamethasone suppresses gene expression and production of IL-13 by human mast cell line and lung mast cells

BACKGROUND

IL-13 has been shown to induce IgE production in B cells by promoting class switching to IgE. Mast cells are known to play an important role in the pathogenesis of allergic diseases. We evaluated the ability of human mast cells to produce IL-13 using human mast cell line HMC-1 and freshly isolated lung mast cells and then examined the effect of dexamethasone on the gene expression and production of IL-13 by these cells.

METHODS

HMC-1 cells and lung mast cells were cultured with 10 ng/ml phorbol 12-myristate 13-acetate (PMA) and 1 micromol/L ionomycin and with 5 microg/ml phytohemagglutinin (PHA) and 10 ng/ml PMA, respectively, in the presence of dexamethasone. The gene expression of IL-13 at 3 hours (HMC-1 cells) or 12 hours (human lung mast cells) after stimulation was assessed semiquantitatively by sequential reverse transcription-polymerase chain reaction and Southern blot analysis. IL-13 production at 12 hours after stimulation was assayed by ELISA.

RESULTS

The gene expression of IL-13 by HMC-1 cells and human lung mast cells, which was detected at a low level in an unstimulated condition, was increased by PMA/ionomycin and suppressed by dexamethasone. The supernatant of HMC-1 cells and human lung mast cells showed a low level of IL-13, which was increased by the stimulation and suppressed by dexamethasone.

CONCLUSION

These findings indicate that HMC-1 cells and human lung mast cells produce IL-13 and that dexamethasone suppresses the production of IL-13 by these cells through an inhibitory action on the gene expression.

The effect of pentoxifylline (PTX) on Theiler's murine encephalomyelitis (TMEV)-induced demyelinating disease

Pentoxifylline (PTX) has been recently shown to have a variety of immunomodulatory effects. PTX suppresses the production of tumor necrosis factor-alpha (TNF-alpha) and T helper type 1 (Th1) cytokine, interferon-gamma (IFN-gamma), whereas it increases the production of Th2 cytokines, such as interleukin-4 (IL-4) and IL-10. In the pathogenesis of Theiler's murine encephalomyelitis virus (TMEV)-induced demyelinating disease (TMEV-IDD), encephalitogenic Th1 cells may play a major role. We examined the effect of PTX treatment on TMEV-IDD. We treated SJL/J mice, inoculated TMEV intracerebrally, with either PTX or saline from days -2 to 12 and days 14 to 27 postintracerebral infection. In the group of mice treated with PTX from days -2 to 12, the onset of TMEV-IDD was suppressed. On the other hand, in the group of mice treated with PTX from days 14 to 27 or saline, the onset of TMEV-IDD was not inhibited. The results of enzyme-linked immunospot (ELISPOT) assay of spleen cells of mice showed that the production of TNF-alpha and IFN-gamma was significantly inhibited (TNF-alpha and IFN-gamma, p < 0.001) and IL-4 and IL-10 production was significantly increased (IL-4, P < 0.001; and IL-10, P < 0.05, respectively) in the group of mice treated with PTX from days -2 to 12. These findings suggest that PTX suppresses the onset of TMEV-IDD by suppressing the production of TNF-alpha and modulating Th1-dominant immune responses into Th2-dominant ones.

Suppression of gene expression and production of interleukin 13 by dexamethasone in human peripheral blood mononuclear cells

We examined the effect of dexamethasone on the gene expression and production of interleukin (IL)-13 by human peripheral blood mononuclear cells from healthy controls. The gene expression was assessed semiquantitatively by sequential transcription polymerase chain reaction and Southern blot analysis, and the production of this cytokine was assessed by enzyme-linked immunosorbent assay (ELISA). Dexamethasone suppressed IL-13 gene expression induced by stimulation with phytohemagglutinin and phorbol 12-myristate 13-acetate in a dose-dependent manner, with 96% suppression at 10(-6) M, and also suppressed the increased production of IL-13. This is suggested to be one of the mechanisms by which glucocorticoids suppress allergic inflammation.

Detection of surfactant protein-A gene transcript in the cells from pleural effusion for the diagnosis of lung adenocarcinoma

PURPOSE

To determine whether detecting surfactant protein-A (SP-A) gene transcript in the cells from pleural effusion is useful for the diagnosis of lung adenocarcinoma.

PATIENTS AND METHODS

We performed reverse transcription polymerase chain reaction (RT-PCR) analysis of SP-A gene transcript in the cells of pleural effusion from 42 consecutive patients with pleural effusion, including 7 patients with primary lung adenocarcinoma before their treatments.

RESULTS

A cDNA segment of SP-A was amplified from the pleural fluid cells of all patients with primary lung adenocarcinoma, indicating the presence of the SP-A gene transcript. None of the remaining patients, including those with metastatic lung adenocarcinoma, showed positive for the SP-A gene transcript.

CONCLUSION

These findings indicate that RT-PCR analysis of the SP-A gene transcript in pleural effusion is useful for the diagnosis of primary lung adenocarcinoma.

Patch-clamp characterization of secretory process in human basophils

The effects of the intracellular Ca2+ concentration ([Ca2+]i) and a nonhydrolyzable guanosine triphosphate, guanosine 5'-o-(3-thiotriphosphate) (GTP-gamma-S), on secretion were studied by a patch-clamp technique in human basophils. When 10 microM Ca2+ were applied intracellularly, the granules dispersed rapidly, moved vigorously and fused to the cell membrane in 5 min. When the cells were exposed to 2 microM [Ca2+]i and 100 microM GTP-gamma-S, the granules dispersed gradually and granule fusion continued for 7-10 min. The plasma membrane conductance did not appreciably change with either 10 microM [Ca2+]i alone or 2 microM [Ca2+]i + 100 microM GTP-gamma-S. Intracellular application of Ca2+, 1-10 microM, caused a dose-dependent increase in cell membrane capacitance, which reflects granule membrane fusion, indicating exocytosis in a Ca2+ concentration-dependent manner. The addition of 100 microM GTP-gamma-S promoted an increase in the plasma membrane capacitance at concentrations from 0.1 to 2 microM [Ca2+]i and at 2 microM [Ca2+]i the increase was 4.4 times greater than that with 2 microM [Ca2+]i alone. These results indicate that certain G protein(s) promote Ca2+-dependent exocytosis in human basophils.

Signature current of SO2-induced bronchitis in rabbit

To investigate abnormalities of airway epithelial ion transport underlying chronic inflammatory airway diseases, we performed electrophysiological, histological, and molecular biological experiments using rabbits exposed to SO2 as a model of bronchitis. By comparison with control, the SO2-exposed trachea exhibited decreased short circuit current (Isc) and conductance associated with increased potential difference. In normal trachea, apical ATP induced a transient Isc activation followed by a suppression, whereas the bronchitis model exhibited a prolonged activation without suppression. This pathological ATP response was abolished by diphenylamine 2-carboxylate or Cl--free bath solution. A significant increase in net Cl- flux toward the lumen was observed after ATP in our bronchitis model. Isoproterenol or adenosine evoked a sustained Isc increase in SO2-exposed, but not in normal, tracheas. The Northern blot analysis showed a strong expression of cystic fibrosis transmembrane conductance regulator (CFTR) mRNA in SO2-exposed epithelium. The immunohistochemical study revealed a positive label of CFTR on cells located luminally only in SO2-exposed rabbits. We concluded that the prolonged ATP response in our bronchitis model was of a superimposed normal and adenosine-activated current. The latter current was also activated by isoproterenol and appeared as a signature current for the bronchitis model airway. This was likely mediated by CFTR expressed in the course of chronic inflammation.

Renal angiotensin-converting enzyme localization in diabetic rats and the effect of low protein diet

Recent evidence suggests a role of angiotensin-converting enzyme (ACE) in diabetic nephropathy. The effect of diabetes and low protein diet on renal immunohistochemical ACE localization was studied in streptozotocin-induced DM rats. Immunohistochemical ACE localization was reduced in DM rats, and a low protein diet partially resolved this abnormality while inhibiting the progression of diabetic nephropathy.

Renal hemodynamic changes induced by captopril and angiotensin-converting enzyme gene polymorphism

We studied the relationship between renal hemodynamic changes induced by a single acute administration of captopril (50 mg p.o.) and angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism in 27 healthy human volunteers, 7 with DD genotype, 10 with ID, and 10 with II genotype. The increase in effective renal plasma flow (p < 0.02) and the fall in renal vascular resistance (p < 0.01) in response to captopril were significantly less in subjects with the DD genotype than in subjects with the other genotypes. These data suggest that intrarenal ACE inhibition by captopril differs according to ACE gene ID polymorphism in healthy humans.

Dexamethasone suppressed gene expression and production of interleukin-10 by human peripheral blood mononuclear cells and monocytes

Interleukin-10 (IL-10) is known to inhibit T cell-mediated responses. IL-10 has also been shown to play an important pathogenetic role in allergic diseases. Glucocorticoid is known to inhibit the production and gene expression of many cytokines which induce inflammatory reactions. We examined the effect of dexamethasone on the gene expression and production of IL-10 by human peripheral blood mononuclear cells (PBMCs) and monocytes. PBMCs and monocytes from 5 healthy volunteers were incubated with or without dexamethasone for 1 h, then stimulated with 5 micrograms/ml lipopolysaccharide (LPS). Gene expression and production of IL-10 by human PBMCs were detected without stimulation and increased by LPS stimulation. Dexamethasone suppressed the gene expression and production of IL-10 by LPS-stimulated PBMCs in a dose-dependent manner by 41.6 and 61.1% at 10(-6) M, respectively. Also in monocytes, the gene expression and production of IL-10 were detected without stimulation, increased by LPS stimulation, and significantly suppressed by dexamethasone by 53.1 and 61.2% at 10(-6) M, respectively. This suppressive effect on IL-10 gene expression was not so potent compared with its effect on cytokines such as IL-5. The suppression of IL-10 production by glucocorticoid is suggested to be one of the important mechanisms by which glucocorticoids suppress allergic inflammation in the treatment of allergic diseases.

[A study on the pathogenesis of hepatomegaly in patients with Crow-Fukase syndrome]

We studied pathogenesis of hepatomegaly in Crow-Fukase syndrome. Hepatocytes were isolated from BALB/c mice and cultured with serum or ascites of three patients with Crow-Fukase syndrome. After 24 hours culture, total number of hepatocytes was counted. The levels of human hepatocyte growth factor (h-HGF) in the serum were also measured. In the hepatocyte culture study, the numbers of hepatocytes after 24 hours cultured in the serum of two patients were significantly larger than those of the control group. When the hepatocytes were cultured with patients' serum after corticosteroid therapy, the survival numbers were markedly reduced. The serum levels of h-HGF in our three patients were 0.62, 0.52, 0.53 ng/ml respectively. They were all slightly higher than normal values (< or = 0.39 ng/ml). Our study indicates that in the serum or ascites of patients with Crow-Fukase syndrome, there may be some humoral factors other than h-HGF, which promote proliferation of hepatocyte or protect hepatocyte.

[The detection of factors that may promote the hepatocyte proliferation in the serum of a patient with crow-fukase syndrome]

We reported a case of Crow-Fukase syndrome and examined the mechanism of hepatomegaly in Crow-Fukase syndrome. A 67-year-old woman was presented with polyneruopathy, hepatosplenomegaly, pericardial effusion and M proteinemia. On examination, all laboratory data and clinical symptoms were compatible with Crow-Fukase syndrome. The patient was treated with prednisolone and immunoadsorption plasmaphresis therapy. All the clinical manifestations including hepatomegaly gradually improved. In order to examine whether some factors that promote the prolifelation of hepatocyte may exist in the patient's serum, we cultured mouse hepatocyte in the presence of patient's or control serum together. Though the number of hepatocytes decreased after 2 days culture, the number of hepatocytes cultured with patient's serum in active disease stage remained significantly greater than of hepatocytes cultured with either control serum or patient's serum in healing stage. There were no abnormal pathological findings in biopsied liver. Liver suggesting that hepatomegaly was the results of normal hepatocytes proliferation. Taken together, these findings suggest there were some factors that may promote the proliferation of hepatocytes or may have protective effect of hepatocyte in patient's serum. Though the level of human hepatocyte growth factor (h-HGF) in patient's serum in active disease stage was slightly increased, hepatomegaly cannot be attributable solely to h-HGF. Organomegaly is one of the important symptoms of the Crow-Fukase syndrome, however, in so far as we are aware its mechanism is not examined. In this report it is suggested that several unknown factors other than h-HGF may contribute the hepatomegaly of the Crow-Fukase syndrome.

Effect of lithium on serum calcium level and parathyroid function in manic-depressive patients

The purpose of this study is to find out whether hypercalcemia and hyperparathyroidism are rare or not in manic-depressive patients taking lithium carbonate. The subjects were 13 patients receiving lithium and 19 healthy subjects not receiving it as normal controls. Serum ionized calcium (Ca++), serum parathyroid hormone (PTH), urinary calcium and cyclic AMP(cAMP) were measured. Cervical ultrasonographic examination was also performed. The mean serum Ca++ level in the lithium administered group was significantly higher than that in the control group (P < 0.02). There was no significant difference between the serum PTH levels in the two groups. The mean urinary calcium level in the lithium administered group was below the normal range, but the mean urinary of cAMP level was within the normal range. Although a parathyroid cyst was found in one lithium administered patient on ultrasonographic examination, no swelling of the parathyroid gland was observed in the other patients in the lithium administered group or in any of the control subjects. In the present study, no distinct hyperparathyroidism was found in the patients in the lithium administered group. Lithium administration affects calcium metabolism in manic-depressive patients and hypercalcemia seems to be one of the complications needing attention at the time of lithium administration.

Angiotensin-converting enzyme polymorphism and development of diabetic nephropathy in non-insulin-dependent diabetes mellitus

We determined the distribution frequency of angiotensin-converting enzyme insertion/deletion (I/D) polymorphism in 111 Japanese patients with non-insulin-dependent diabetes mellitus (NIDDM) of at least 10 years duration (80 patients with diabetic nephropathy and 31 patients without nephropathy) and 76 healthy Japanese controls. Patients with diabetic nephropathy showed an excess of the ID genotype compared with patients without nephropathy (p < 0.02) and less of the II genotype compared with healthy controls (p < 0.01) and patients without nephropathy (p < 0.01). NIDDM patients with the II genotype have a decreased risk for the development of diabetic nephropathy.

Amino acid-induced hyperfiltration--mediators and effect of captopril

Mediators and the effect of captopril on amino acid-induced hyperfiltration were studied. Acute intravenous L-arginine (arginine) infusion tests were performed twice, without captopril administration in 6 normal subjects (group I), before and after pretreatment with captopril in 10 normal subjects (group II) and 10 IgA nephropathy patients with slight renal dysfunction (group III). It was found that in all groups with and without captopril, arginine infusion led to a significant decrease in renal vascular resistance, and significant increases in renal plasma flow and plasma glucagon level. GFR was significantly increased in response to arginine only in normals without captopril pretreatment. Captopril pretreatment attenuated the rise in GFR following arginine infusion in normal subjects. Plasma renin activity and urinary cGMP were significantly increased in response to arginine only in normals without captopril pretreatment. No significant increase in urinary PGE2 was observed after arginine infusion in any groups. It was concluded that cGMP and glucagon are possible mediators for arginine-induced hyperfiltration and inhibition of renin-angiotensin system attenuates the arginine-induced rise in GFR.

Glucocorticoids suppressed production and gene expression of interleukin-5 by peripheral blood mononuclear cells in atopic patients and normal subjects

BACKGROUND

Interleukin-5 (IL-5) is known to play a major role in regulating eosinophil function in atopic diseases, including bronchial asthma. Glucocorticoids are most effective agents for treating these diseases. However, their mechanism remains unclear. We examined the effects of glucocorticoids on the production and gene expression of IL-5 in atopic patients and normal subjects.

METHODS

Human peripheral blood mononuclear cells (PBMCs) in five atopic and four normal subjects were cultured with phytohemagglutinin and phorbol 12-myristate 13-acetate (PMA) in the presence of dexamethasone. IL-5 secreted by PBMCs was assayed by ELISA. Gene expression of IL-5 by PBMCs was assessed semiquantitatively by sequential reverse transcription-polymerase chain reaction, and Southern blot analysis.

RESULTS

Phytohemagglutinin/PMA-stimulated PBMCs from all atopic patients and three normal subjects secreted detectable amounts of IL-5, which were suppressed by dexamethasone in a dose-dependent manner, with 85.8% suppression at 10(-6) mol/L. Gene expression of IL-5 was detected by reverse-transcription polymerase chain reaction in PBMCs from all subjects, even when not stimulated; was increased by stimulation; and was suppressed by dexamethasone. The concentration of dexamethasone resulting in 50% inhibition in IL-5 gene expression did not differ between atopic patients and normal subjects.

CONCLUSION

These findings indicate that dexamethasone suppressed IL-5 production in atopic human PBMCs through an inhibitory action on the gene expression. These results suggest that the suppression of IL-5 production through the suppression of IL-5 gene expression is one of the most important mechanisms by which glucocorticoids inhibit eosinophil functions in the treatment of atopic diseases, including bronchial asthma.

Nucleotide sequence of a rice cDNA similar to a maize NADP-dependent malic enzyme

We have isolated a rice cDNA clone that is homologous to the gene for the maize NADP-dependent malic enzyme (EC 1.1.1.40; NADP-ME). The deduced amino acid sequence coded for by the cDNA indicates a high level of homology to chloroplast type NADP-ME, including a transit peptide with pronounced hydrophobic properties at the amino terminus. Northern blot analysis indicates that the expression of this gene is regulated by external stress such as submergence.

A functional analysis of another individual's behavior as discriminative stimulus for a monkey

Key presses of 1 monkey (called the performer) became the basis upon which a 2nd monkey (called the judge) solved conditional-discrimination tasks. First, the performer was trained to press one of two colored choice keys (red or green) depending on the location of a white light in her chamber. The performer's key-pressing behavior was brought under the control of the experimenter by this procedure. Subsequently, the judge was trained to discriminate the performer's key-pressing behavior. In Experiment 1, the judge had to press Key 1 when the performer pressed the red choice key and Key 2 when the performer pressed the green choice key. In Experiment 2, a sample key was introduced. The judge had to press Key 1 when the performer pressed the same colored choice key as the sample; the judge had to press Key 2 when the performer pressed the different colored choice key. In both experiments, the judge was required to attend to the behavior of the performer. It was shown that the performer's behavior served as a discriminative stimulus for the judge's responses in a conditional-discrimination task.

[A phase III multi-center clinical trial on 123I-orthoiodohippurate (123I-OIH)]

A multi-center clinical trial was performed to evaluate the clinical usefulness of 123I-orthoiodohippurate (123I-OIH) in patients with renal and urinary disorders. 123I-OIH was evaluated to be "safe" in all 259 cases it was injected. 123I-OIH was useful in all 248 cases analyzed for the overall clinical usefulness evaluated by the investigators. The clinical significance of the drug was also evaluated in terms of renal blood flow function, renal parenchymal function, urinary function and the ability to differentiate between renal and urinary disorders. In the comparison with 123I-OIH (90 cases), 123I-OIH was superior as evaluated by the investigators and the Committee both. In the comparison with 99mTc-DTPA (113 cases), 123I-OIH was evaluated as superior by the investigators, but no significant difference was found by the Committee. In image qualities, 123I-OIH was evaluated as superior to 131I-OIH and equal to 99mTc-DTPA by the Committee. In overall efficiency, 123I-OIH was evaluated as being more valuable than 131I-OIH in 92% of the 90 cases and more valuable than 99mTc-DTPA in 50% of the 113 cases. 123I-OIH was evaluated as being less valuable than 131I-OIH in no cases and less valuable than 99mTc-DTPA in 7% of the 113 cases. These results suggest that 123I-OIH is superior to 131I-OIH and equal or superior to 99mTc-DTPA as a radiopharmaceutical for gamma camera-renography.

Influence of gestation on renal function in gravida with IgA nephropathy

Nineteen pregnancies in 17 women with IgA nephropathy (IgAGN) were studied in terms of the influence of gestation on the natural course of renal function in IgAGN. We performed serial examinations of the serum creatinine (S-Cr) levels before and during pregnancy and after delivery. Group I comprised 11 pregnancies in 10 gravida who revealed proteinuria (1.1 +/- 0.7 g/day; mean +/- SD) and microhematuria before pregnancy. The S-Cr before pregnancy averaged 0.86 +/- 0.13 mg/dl. Group II comprised 8 pregnancies in 7 gravida who showed isolated microhematuria. The S-Cr before pregnancy averaged 0.81 +/- 0.06 mg/dl. In group I, S-Cr did not decrease during pregnancy and was elevated at delivery and at 1-4 weeks after delivery (1.03 +/- 0.29 mg/dl, p less than 0.05) in comparison with the level before pregnancy. In group II, S-Cr decreased significantly during pregnancy and was not elevated at delivery or after delivery. The above results suggest that gestation had a slight and transient adverse effect on renal function in IgAGN with proteinuria.