Single administration effects of ethanol on the distribution of white blood cells in rats

Acute single administration effects of ethanol on the distribution of total white blood cells (WBCs), neutrophil, basophil, eosinophil, monocyte and lymphocytes were studied in rats. Acute single administration effects of ethanol on the number of red blood cells (RBCs), hemoglobin concentration and hematocrit were also examined. Male 8-week-old Sprague Dawley rats were randomly divided into the ethanol-administered (ETA) group and the control (CON) group. Two parts of an experiment, 1) 1st experiment : (ethanol dose : 1.0 g/kg body weight), and 2) 2nd experiment : (ethanol dose : 2.0 g/kg body weight) were carried out in rats. The rats were starved to 19:00, and deprived of diet for 12 hr and water for 1 hr before the single administration of ethanol. 1.0 or 2.0 g/kg body weight of ethanol (in 20% (w/w) ethanol) was orally administered to ETA group rats via a stainless stomach tube. In the CON group rats, 0.9% NaCl solution was orally given with the solution volume being equal, in the same manner. Single administration of 1.0 or 2.0 g/kg body weight of ethanol did not change the number of RBCs, hemoglobin concentration and hematocrit. Single administration of 1.0 g/kg body weight of ethanol did not also change the number of WBCs. However, administration of 2.0 g/kg body weight of ethanol increased significantly the number of neutrophil, basophil, monocyte and total WBCs without changing the number of eosinophil and lymphocytes. These results suggest that single administration of 2.0 g/kg body weight of ethanol to rats increased markedly the number of the natural immunity cells without changing the number of acquired cells.

Age-related effects of fasting on ketone body production during lipolysis in rats

OBJECTIVE

The age-related effects of fasting on lipolysis, the production of ketone bodies, and plasma insulin levels were studied in male 3-, 8-, and 32-week-old Sprague-Dawley rats.

METHODS

The rats were divided into fasting and control groups. The 3-, 8- and 32-week-old rats tolerated fasting for 2, 5, and 12 days, respectively.

RESULTS

Fasting markedly reduced the weights of perirenal and periepididymal white adipose tissues in rats in the three age groups. The mean rates of reduction in both these adipose tissue weights during fasting periods were higher in the order of 3 > 8 > 32-week-old rats. Fasting transiently increased plasma free fatty acid (FFA), total ketone body, β-hydroxybutyrate, and acetoacetate concentrations in the rats in the three age groups. However, plasma FFA, total ketone body, β-hydroxybutyrate, and acetoacetate concentrations in the 3-week-old rats reached maximal peak within 2 days after the onset of fasting, although these concentrations in the 8- and 32-week-old rats took more than 2 days to reach the maximal peak. By contrast, the augmentation of plasma FFA, total ketone body, β-hydroxybutyrate, and acetoacetate concentrations in the rats in the three age groups had declined at the end of each experimental period. Thus, the capacity for fat mobilization was associated with tolerance to fasting. Plasma insulin concentrations in the rats in the three age groups were dramatically reduced during fasting periods, although basal levels of insulin were higher in the order of 32 > 8 > 3 week-old rats.

CONCLUSION

These results suggest that differences in fat metabolism patterns among rats in the three age groups during prolonged fasting were partly reflected the metabolic turnover rates, plasma insulin levels, and amounts of fat storage.

Hypoxic regulation of glycosylation via the N-acetylglucosamine cycle

Glucose is an energy substrate, as well as the primary source of nucleotide sugars, which are utilized as donor substrates in protein glycosylation. Appropriate glycosylation is necessary to maintain the stability of protein, and is also important in the localization and trafficking of proteins. The dysregulation of glycosylation results in the development of a variety of disorders, such as cancer, diabetes mellitus and emphysema. Glycosylation is kinetically regulated by dynamically changing the portfolio of glycosyltransferases, nucleotide sugars, and nucleotide sugar transporters, which together form a part of what is currently referred to as the ”Glycan cycle”. An excess or a deficiency in the expression of glycosyltransferases has been shown to alter the glycosylation pattern, which subsequently leads to the onset, progression and exacerbation of a number of diseases. Furthermore, alterations in intracellular nucleotide sugar levels can also modulate glycosylation patterns. It is observed that pathological hypoxic microenvironments frequently occur in solid cancers and inflammatory foci. Hypoxic conditions dramatically change gene expression profiles, by activating hypoxia-inducible factor-1, which mediates adaptive cellular responses. Hypoxia-induced glycosyltransferases and nucleotide sugar transporters have been shown to modulate glycosylation patterns that are part of the mechanism associated with cancer metastasis. Hypoxia-inducible factor-1 also induces the expression of glucose transporters and various types of glycolytic enzymes, leading to shifts in glucose metabolic patterns. This fact strongly suggests that hypoxic conditions are an important factor in modulating various nucleotide sugar biosynthetic pathways. This review discusses some of the current thinking of how hypoxia alters glucose metabolic fluxes that can modulate cellular glycosylation patterns and consequently modify cellular functions, particularly from the standpoint of the N-acetylglucosamine cycle, a part of the ”Glycan cycle”.

Acute effects of dihydrocapsaicin and capsaicin on the distribution of white blood cells in rats

The acute effects of dihydrocapsaicin (DHC) and capsaicin (CAP) on the number of white blood cells (WBCs), neutrophils, eosinophils, basophils, monocytes, lymphocytes, T lymphocytes, B lymphocytes and NK cells, and serum corticosterone levels were studied in rats. Male 7-wk-old SD rats were divided into DHC (3.0 mg/kg BW), CAP (3.0 mg/kg BW) and control (CON) groups. The number of total WBCs was 1.30-1.42 times significantly higher in the DHC group than in the CON group at 6-12 h. The number of neutrophils was 1.62 times significantly higher in the DHC group than in the CON group at 12 h. The number of total WBCs and neutrophils, however, showed no significant changes between the CAP and CON groups. The number of lymphocytes was 0.61 and 0.70 times significantly lower in the DHC and CAP groups than in the CON group at 3 h. The number of T lymphocytes and B lymphocytes was 0.74 and 0.54 times lower in the DHC group than in the CON group, respectively. CAP, however, did not significantly change the number of T lymphocytes or B lymphocytes. No significant changes in the number of NK cells were observed among the three groups. CAP and DHC did not change the number of monocytes, eosinophils or basophils. No significant changes of the serum corticosterone levels were observed among the three groups. In conclusion, capsaicinoids decreased the number of acquired immunity cells, and increased the number of total WBCs and neutrophils without changing the number of monocytes, eosinophils or basophils. The magnitude of these effects was relatively higher in DHC than in CAP.

Beta2-adrenergic receptor regulate Toll-like receptor 4-induced late-phase NF-kappaB activation

Stimulation of Toll-like receptor 4 (TLR4) by lipopolysaccharide (LPS) triggers myeloid differentiation factor 88 (MyD88)-dependent early-phase NF-kappaB activation and Toll/IL-1 receptor domain-containing adaptor-inducing IFN-beta (TRIF)-dependent late-phase NF-kappaB activation. In a previous study, we have shown that beta(2)-adrenergic receptor (beta(2)AR) functions as a negative regulator of NF-kappaB activation through beta-arrestin 2 in the macrophage cell line RAW264 and that down-regulation of beta(2)AR expression in response to LPS is essential for NF-kappaB activation and expression of its target gene, inducible nitric oxide synthase (NOS II). Here, we demonstrate that beta(2)AR plays an important role in TRIF-dependent late-phase NF-kappaB activation. LPS-stimulated down-regulation was induced in MyD88-knockdown cells, but not in TRIF-knockdown cells, suggesting that beta(2)AR expression was down-regulated by the TRIF-dependent pathway. On the other hand, depletion of beta(2)AR or beta-arrestin 2 expression by siRNA decreased cytoplasmic IkappaB alpha and abrogated late-phase IkappaB alpha degradation and NF-kappaB activation in response to LPS. Inducible nitric oxide synthase (NOS II) expression was increased continuously during 24 h of LPS stimulation in control cells, but decreased in beta(2)AR or beta-arrestin 2-knockdown cells after 6 h of LPS stimulation. These findings suggest that beta(2)AR functions not only as a negative regulator of NF-kappaB activation, but also as a stabilizing factor of the NF-kappaB/IkappaB alpha complex through cytoplasmic beta-arrestin 2, and that TRIF-dependent down-regulation of beta(2)AR expression increases the level of cytoplasmic NF-kappaB/IkappaB alpha complex free from beta-arrestin 2, leading to continuous late-phase NF-kappaB activation.

Apoptosis induction preceded by mitochondrial depolarization in multiple myeloma cell line U266 by 2-aminophenoxazine-3-one

The aim of the present study was to investigate the mechanism of apoptosis in human multiple myeloma cell line, U266, caused by 2-aminophenoxazine-3-one (Phx-3). Flow-cytometrical and morphological analyses showed that Phx-3 increased the population of annexin V-positive cells including early stage apoptotic cells and late stage apoptotic cells and induced DNA fragmentation or apoptotic body formation in U266 cells, indicating that Phx-3 induced the apoptosis of U266 cells. Activity of caspase-3 was extensively increased in U266 cells treated with Phx-3 time-dependently within 24 h, but this Phx-3-stimulated activity of the enzyme in the cells was completely cancelled by the addition of N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), a pan-caspase inhibitor. The addition of z-VAD-fmk almost blocked the apoptotic effect of Phx-3 against U266 cells, indicating that Phx-3-induced apoptosis of U266 cells was dependent on a caspase signaling pathway. Moreover, the apoptosis of U266 cells occurred after the induction of cell cycle arrest of the cells in the S and G(2)/M phase, the loss of mitochondrial membrane potential, and activation of caspase-3 reached maximum, which were caused by Phx-3 within 24 h. These results support the views that the apoptosis of U266 cells caused by Phx-3 may be preceded by the cell cycle arrest, depolarization of mitochondria and activation of caspase-3. These results support the view that Phx-3 may be utilized in future as chemotherapeutic agent against multiple myeloma which is extremely refractory to chemotherapy.

Phenoxazine derivative, 2-amino-4,4alpha-dihydro-4alpha,7-dimethyl-3H-phenoxazine-3-one suppresses growth of human retinoblastoma cell line Y79 in vitro and in vivo

The aim of the study was to evaluate the in vitro and in vivo antitumor effects of the 2-amino-4,4alpha-dihydro-4alpha,7-dimethyl-3H-phenoxazine-3-one (Phx-1) on the human retinoblastoma cell line Y79. The in vitro effects of Phx-1 on cell viability and apoptosis of the human retinoblastoma Y79 cells, were studied by using colorimetric and flow-cytometric methods. The in vivo antitumor effects of Phx-1 on the human retinoblastoma Y79 cells subcutaneously transplanted in BALB/c nude mice were studied, examining the tumor size, the adverse effects on the mice and the histopathological evaluations including hematoxylin and eosin and immunohistochemical staining in the mass of tumors of human retinoblastoma Y79 cells isolated from the mice. Phx-1 suppressed the viability of Y79 cells dose- and time-dependently and induced apoptosis in Y79 cells in vitro. Phx-1 markedly reduced the growth of Y79 cells transplanted into the mice without causing bodyweight loss. Pathological findings of the tumor mass isolated from mice revealed that the tumor of Y79 cells treated with Phx-1 had a decreased mitotic index, decreased expression of Ki67 and p53, no alteration of bcl-2 level and increased caspase-3 activity compared with the the control. Present results suggested that Phx-1 demonstrated antitumor activity against the human retinoblastoma Y79 cells in vitro and in vivo, by inhibiting cell growth and inducing apoptosis. In addition, Phx-1 exerted few adverse side effects on the mice. Phx-1 may be a useful antitumor drug in the treatment of retinoblastoma, which is the most common and serious intraocular malignant tumor.

Beta2-agonist clenbuterol induced changes in the distribution of white blood cells in rats

Clenbuterol [CLE: 4-amino-alpha(t-butyl-amino)methyl-3,5-dichlorobenzyl alcohol] is well known as a potent beta2-adrenergic agonist and non-steroidal anabolic drug, and thus it is generally used for sports doping and asthma therapy. Although the functions of immune cells such as white blood cells (WBCs) have shown to be modulated through beta2-adrenoceptors, the effects of CLE on immune-responsive systems have not been elucidated systematically. Therefore, the effects of CLE on the number of WBCs were studied in rats. Male adult rats were divided into CLE-administered group and the control group to compare the number of total WBCs, neutrophils, monocytes, lymphocytes, eosinophils, and basophils. The administration (dose = 1.0 mg . kg(-1) body weight . day(-1), s.c.) of CLE was maintained for 30 days. CLE did not change the number of total WBCs during the experimental period. However, CLE increased significantly the number of neutrophils and monocytes, while CLE decreased drastically the number of lymphocytes and eosinophils. There was no significant change in the number of basophils between both groups. These results suggest that the administration of CLE induces drastic redistribution of WBCs in circulation without changing the number of total WBCs, and these responses of WBCs during the administration of CLE are sustained for at least 30 days.

Phenoxazine derivatives 2-amino-4,4alpha-dihydro-4alpha-phenoxazine-3-one and 2-aminophenoxazine-3-one-induced apoptosis through a caspase-independent mechanism in human neuroblastoma cell line NB-1 cells

The aim of the present study was to determine whether phenoxazines such as 2-amino-4,4-alpha-dihydro-4alpha-phenoxazine-3-one (Phx-1) and 2-aminophenoxazine-3-one (Phx-3) may suppress the proliferation of human neuroblastoma cell line, NB-1 that is refractory to chemotherapeutic agents, inducing apoptosis through the activation of caspase pathway or not. Phx-1 and Phx-3 suppressed the proliferation of NB-1 cells extensively dependent on dose and time. The IC50 of Phx-1 and Phx-3 was about 20 microM and 0.5 microM, respectively, when the cells were treated with Phx-1 or Phx-3 for 72 h. Phx-1 and Phx-3 caused the mixed types of cell death-apoptosis and necrosis-in NB-1 cells, which was detected by flow cytometry. The induction of apoptosis/necrosis caused by these phenoxazines seemed to be correlated dominantly with the caspase independent pathway, because the increased activity of effector caspase 3/7 in NB-1 cells caused by 50 microM Phx-1 or 20 microM Phx-3 was completely cancelled by the addition of z-VAD-fmk, a pan-caspase inhibitor, but such phenoxazines-suppressed viability of NB-1 cells was not recovered to normal levels by this inhibitor. The results of this study demonstrate that Phx-1 and Phx-3 have antitumor activity against the neuroblastoma cell line, NB-1, though the IC50 was extremely low for Phx-3, inducing the mixed types of cell death, apoptosis and necrosis, caspase-independently.

Depressed contractile reserve and impaired calcium handling of cardiac myocytes from chronically unloaded hearts are ameliorated with the administration of physiological treatment dose of T3 in rats

AIM

Chronic cardiac unloading causes a time-dependent upregulation of phospholamban (PLB) and depression of myocyte contractility in normal rat hearts. As thyroid hormone is known to decrease PLB expression, we examined whether thyroid hormone restores the depressed contractile performance of myocytes from chronically unloaded hearts.

METHODS

Cardiac unloading was induced by heterotopic heart transplantation in isogenic rats for 5 weeks. Animals were treated with either vehicle or physiological treatment dose of 3,5,3'-triiodo-L-thyronine (T3) that does not cause hyperthyroidism for the last 3 weeks (n=20 each).

RESULTS

In vehicle-treated animals, myocyte relaxation and [Ca2+]i decay were slower in unloaded hearts than in recipient hearts. Myocyte shortening in response to high [Ca2+]o was also depressed with impaired augmentation of peak-systolic [Ca2+]i in unloaded hearts compared with recipient hearts. In vehicle-treated rats, protein levels of PLB were increased by 136% and the phosphorylation level of PLB at Ser16 were decreased by 32% in unloaded hearts compared with recipient hearts. By contrast, in the T3-treated animals, the slower relaxation, delayed [Ca2+]i decay, and depressed contractile reserve in myocytes from unloaded hearts were all returned to normal levels. Furthermore, in the T3-treated animals, there was no difference either in the PLB protein level or in its Ser16-phosphorylation level between unloaded and recipient hearts.

CONCLUSION

These results suggest that the treatment with physiological treatment dose of thyroid hormone rescues the impaired myocyte relaxation and depressed contractile reserve at least partially through the restoration of PLB protein levels and its phosphorylation state in chronically unloaded hearts.

2-aminophenoxazine-3-one suppresses the growth of mouse malignant melanoma B16 cells transplanted into C57BL/6Cr Slc mice

Since phenoxazine is an essential structure of actinomycin D, which exerts a strong anticancer effect, we examined the anticancer effect of 2-aminophenoxazine-3-one (Phx-3) on mouse malignant melanoma B16 cells in vitro and in vivo. Phx-3 inhibited proliferation of the B16 cells in a dose-dependent manner in vitro. We furthermore studied the in vivo effects of Phx-3 on mouse malignant melanoma B16 cells transplanted in female C57BL/6Cr Slc mice. Treatment with Phx-3 (0.5 mg/kg) completely suppressed the growth of mouse malignant melanoma B16 cells transplanted in mice as compared with the control group. Phx-3 was found to exert few adverse effects, in terms of bodyweight loss, changes in serum levels of blood biochemical parameters such as aspartate transaminase (AST), alanine transaminase (ALT), blood urea nitrogen (BUN) and creatinine, dysfunction of the liver and the kidney examined by pathological methods, piloerection and wasting, when mice were treated with a dose of 0.5 mg/kg. These results suggest that Phx-3 may be used to treat patients affected by malignant melanoma in future.

Caspase-independent cell death revealed in human gastric cancer cell lines, MKN45 and KATO III treated with phenoxazine derivatives

We examined whether phenoxazine derivatives such as 2-amino-4,4alpha-dihydro-4alpha,7-dimethyl-3H-phenoxazine-3-one (Phx-1) and 2-aminophenoxazine-3-one (Phx-3) may have anticancer effects on the human gastric cancer cell lines, MKN45, MKN74, MKN7 and KATO III in vitro. Phx-1 inhibited the growth of these cancer cells in a dose- and time-dependent manner. The IC50 was approximately 65, 25, 100 and 70 microM for MKN45, MKN74, MKN7 and KATO III respectively, after 72 h. Phx-3 exerted stronger antiproliferative effects against these cancer cells (IC50: approximately 5, 1, 10 and 10 microM for MKN45, MKN74, MKN7 and KATO III, respectively, after 72 h) than Phx-1. Phx-1 and Phx-3 increased the population of TUNEL-positive cells in MKN45 and KATO III time-dependently from 24 to 72 h, suggesting that Phx-1 and Phx-3 have apoptotic activity against these gastric cancer cells. The activity of effector caspase-3 significantly increased in MKN45 treated with Phx-3 for 24 h, but did not altered in the cells treated with Phx-1 for 24 h. When z-VAD-fmk, a pan-caspase inhibitor, was co-treated for 24 h, Phx-3-stimulated caspase-3 activity in MKN45 was reversed to the levels of normal activity, while the antiproliferative and apoptotic effects of Phx-3 against the cells were maintained. The activity of caspase-3 was not activated in KATO III by 24 h exposure for Phx-1 or Phx-3. In conclusion, both phenoxazines prevent the growth of the human gastric cancer cell lines, MKN45 and KATO III in vitro, and cause the apoptosis of these cell lines via a caspase-independent pathway. Although the intracellular action mechanisms of Phx-1 and Phx-3 are still unclear, these phenoxazines may be useful for the treatment of gastric cancer in the future.

Phenoxazine derivatives induce caspase-independent cell death in human glioblastoma cell lines, A-172 and U-251 MG

The apoptotic effects of 2-amino-4,4alpha-dihydro-4alpha, 7-dimethyl-3H-phenoxazine-3-one (Phx-1) and 2-aminophenoxazine-3-one (Phx-3) on human glioblastoma cell lines, A-172 and U-251 MG were studied. These phenoxazines extensively decreased the viability of A-172 and U-251 MG cells (IC50 of Phx-1: 60 microM, in both lines; IC50 of Phx-3: 10 and 3 microM, for A-172 and U-251 cells, respectively). Phx-1 and Phx-3 increased the population of annexin V and PI double-positive cells in A-172 and U-251 MG cells, resulting in cell death at late stage apoptosis/necrosis. The activities of caspase-3/7 were greatly increased in A-172 and U-251 MG cells treated with Phx-1 or Phx-3. However, a pan-caspase inhibitor, z-VAD-fmk, failed to reverse the antiproliferative and apoptotic effects of Phx-1 and Phx-3 in both cell lines. In conclusion, Phx-1 and Phx-3 exert significant anti-cancer effects against human glioblastoma cell lines, A-172 and U-251 MG, mediated by the caspase-independent apoptotic cell death pathway.

Effects of two types of inactivity on the number of white blood cells in rats

Prolonged inactivity is known to induce changes in responses of many physiological defense systems such as the hypothalamo-hypophyseal-adrenocortical axis, the sympathetic nervous system, and immuno-responsive systems. However, effects of various types of inactivity on immuno-responsive systems are still unknown. Therefore, the effects of two types of inactivity (immobilization: IMM and whole body suspension: WBS) on the number of white blood cells were studied in rats. Rats were divided into the control group and each inactivity group to compare the number of total white blood cells, lymphocytes, monocyte, neutrophil, eosinophil, and basophil during the experimental periods. Both IMM and WBS were maintained for 11 days. IMM markedly increased the number of total white blood cells, monocyte, neutrophil, and eosinophil in the 1st to 10th day. However, the number of total white blood cells, monocyte, neutrophil, and eosinophil during the experiment of WBS were characterized by the presence of a lag phase followed by the significant increased actions. IMM did not change the number of basophil during the experimental period. However, WBS increased the number of basophil in the 1st to 8th day to 2.8-4.8 times, compared with the values of the control. Both IMM and WBS did not change the number of lymphocytes. From these results, WBS increases the number of natural immunity cells without changing acquired immunity cells, and there are different responses in the number of total white blood cells, monocyte, neutrophil, eosinophil, and basophil between IMM and WBS.

Anticancer effects of phenoxazine derivatives combined with tumor necrosis factor-related apoptosis-inducing ligand on pancreatic cancer cell lines, KLM-1 and MIA-PaCa-2

The aim of this study was to investigate the anticancer effects of the phenoxazine derivatives, 2-amino-4,4alpha-dihydro-4alpha,7-dimethyl-3H-phenoxazine-3-one (Phx-1), 3-amino-1,4alpha-dihydro-4alpha,8-dimethyl-2H-phenoxazine-2-one (Phx-2), and 2-aminophenoxazine-3-one (Phx-3) on human pancreatic cancer cell lines, KLM-1 and MIA-PaCa-2, in combination with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a member of the tumor necrosis factor superfamily of cytokines. Of these three phenoxazines, Phx-1 and Phx-3 inhibited proliferation of KLM-1 dose-dependently, but Phx-2 did not. Phx-3 caused both apoptosis and necrosis in KLM-1 cells, as evidenced by the phosphatidylserine externalization and propidium iodide permeable cells detected by a flow cytometric method using annexin-V and propidium iodide. Down-regulation of Bcl-2 expression appeared to be involved in the Phx-3-induced cell death. TRAIL did not affect proliferation of KLM-1, and the inhibitory effects of Phx-1 and Phx-3 on the KLM-1 cell line were not augmented by the combination with TRAIL. On the other hand, proliferation of the MIA-PaCa-2 cell line was not affected by Phx-1, Phx-2 and Phx-3, although it was significantly inhibited by TRAIL in a dose-dependent manner. Inhibitory effects of TRAIL on MIA-PaCa-2 were synergistically augmented by the addition of Phx-1 and Phx-3, but not by Phx-2. These results suggest that both Phx-1 and Phx-3 exert anticancer effects against human pancreatic cancer cells, KLM-1 and MIA-PaCa-2, through distinct action modes. Phx-1 and Phx-3 may be effective for the treatment of pancreatic cancer.