Radical scavenging activity of bisbenzylisoquinoline alkaloids and traditional prophylactics against chemotherapy-induced oral mucositis.

BACKGROUND AND OBJECTIVE: Oral mucositis is a major severe toxic side-effect of systemic chemotherapy and irradiation in patients with cancer. Various free radical scavengers have been shown to prevent chemotherapy-induced skin necrosis. The objective of this study was to determine the antioxidant activity of a bisbenzylisoquinoline alkaloidal compound (BIQAC) and a series of chemicals, including allopurinol, used clinically for the treatment of chemotherapy-induced mucositis. METHODS: Allopurinol, melatonin, camostat mesilate, gabexate mesilate, hydroquinone and BIQAC were tested for their radical scavenging activities on four different radical species: 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) cation radical (ABTS(*+)) using standard methods, and superoxide anion radical (O(2) (-)) and hydroxyl radical (OH(*)) using electron spin resonance. RESULTS: Allopurinol had radical scavenging activity against O(2) (-) only. Melatonin had strong radical scavenging activity against ABTS(*+), and weak activity against DPPH radical and OH(*). Camostat mesilate had weak radical scavenging activity against OH(*). Gabexate mesilate had no radical scavenging activity against any of these radicals. Hydroquinone had strong radical scavenging activity against DPPH radical and ABTS(*+), and moderate activity against both O(2) (-) and OH(*). BIQAC had moderate radical scavenging activity against DPPH radical, strong radical scavenging activity against ABTS(*+) and O(2) (-), and weak activity against OH(*). CONCLUSION: The BIQAC had the most braod-spectrum radical scavenging activity, suggesting that it may be effective against chemotherapy-induced mucositis. These findings also suggest that this radical-scavenging activity screening method, against four kinds of radicals, may be useful for the screening of radical scavenging activity of new natural and synthetic chemicals.

Serum cholesteryl ester transfer protein concentrations are associated with serum levels of total cholesterol, beta-lipoprotein and apoproteins in patients with type 2 diabetes mellitus.

OBJECTIVE: To investigate the role of serum cholesterol ester transfer protein (CETP) and the metabolism of various lipids including apoproteins in patients with type 2 diabetes. MATERIALS AND METHODS: The relationships between serum concentrations of CETP and various lipids and apoproteins were investigated in 193 patients with type 2 diabetes mellitus and 68 age-matched healthy subjects. Serum CETP concentrations were measured by an enzyme-linked immunosorbent assay. RESULTS: Serum CETP values were lower in diabetic patients than in healthy controls (p < 0.01). Female diabetic patients had significantly higher CETP concentrations than male patients. Serum CETP concentrations exhibited a significant positive correlation with serum concentrations of cholesterol (TC) and beta-lipoproteins in diabetic patients (r = 0.485, p = 0.013). Patients with relatively high serum concentrations of high-density lipoprotein cholesterol (HDL-C) tended to have much lower CETP concentrations than patients with lower HDL-C concentrations. Serum CETP concentrations showed significant positive correlations with those of apoproteins B (Apo B; r = 0.384, p = 0.024) and E (Apo E; r = 0.341, p = 0.035). CONCLUSION: The data indicate that serum CETP is closely involved in the metabolism of TC, beta-lipoprotein, Apo B and Apo E in type 2 diabetic patients.

Small low-density lipoprotein and small low-density lipoprotein/total low-density lipoprotein are closely associated with intima-media thickness of the carotid artery in Type 2 diabetic patients.

BACKGROUND: The intima-media thickness (IMT) of the carotid artery, as determined by ultrasonography, is useful for reflecting the extent of subclinical atherosclerosis. We investigated the relationship between IMT and the serum concentrations of small low-density lipoprotein (LDL) in diabetic patients. METHODS: The study was conducted with 27 Type 2 diabetic patients (14 males and 13 females; mean age=62.6+/-8.3 years) and 12 age-matched healthy controls. The LDL subfraction was measured using a polyacrylamide gel electrophoresis method. Vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) concentrations were measured by an enzyme immunoassay. The IMT was expressed as the maximum IMT (Max-IMT) and average IMT (Ave-IMT) of the carotid artery, measured by ultrasonography. RESULTS: Both the IMT and the small LDL concentrations were significantly increased in the diabetic patients compared with the healthy participants. The IMTs were significantly correlated with small LDL concentration and small LDL/total LDL more than LDL concentrations by multivariate analysis. The IMTs were not significantly correlated with the serum VEGF or PDGF concentrations. The patients with a larger IMT had a significantly higher prevalence of hypertension or ischemic heart disease than did the patients with a normal IMT. CONCLUSIONS: The increased small LDL concentrations and small LDL/total LDL, in addition to total LDL concentrations, in Type 2 diabetic patients are closely associated with increased IMT of the carotid artery.

Clinical usefulness of doxazosin in patients with type 2 diabetes complicated by hypertension: effects on glucose and lipid metabolism.

This uncontrolled study investigated the effects of using the alpha 1-blocker doxazosin (2 mg or 4 mg daily for 3 months) to treat 21 hypertensive patients with type 2 diabetes, including eight obese individuals (body mass index [BMI] > or = 25.0 kg/m2). A significant reduction in systolic and diastolic blood pressure, beginning after 1 month of treatment, was seen. There was no significant change in BMI. Although there was no obvious improvement in glucose metabolism, doxazosin treatment noticeably reduced insulin resistance and significantly lowered triglyceride and free fatty acid levels. No significant changes were found in total cholesterol, high- or low-density lipoprotein-cholesterol, atherosclerotic index, or small or large subfractions of low-density lipoprotein-cholesterol. None of the patients showed any adverse effects. The beneficial effects of doxazosin on blood pressure and lipid and glucose metabolism shown in this study suggest that this drug is clinically useful as an anti-hypertensive agent for patients with diabetes.

The effects of facial fanning on thermal comfort sensation during hyperthermia.

We studied how facial fanning during hyperthermia improves the thermal comfort sensation. Experiments were carried out on ten male subjects. They were immersed in hot water at 40 degrees C for 45 min. At 20 min and 35 min, fanning (1 m x s(-1)) was applied to their faces for 5 min. Core temperature (Tc) measured as esophageal temperature (Tes) and tympanic temperature (Tty) continued to rise during the immersion, but temporarily decreased during fanning with a delay of 2 or 3 min. Skin temperatures (Ts) on the forehead and cheek continued to increase slightly during immersion, but decreased immediately after the start of fanning. During immersion before face fanning, the time trend of thermal sensation towards the warm level was similar to that of skin temperature on the face, whereas the time trend of thermal comfort ratings towards the uncomfortable level was similar to that of Tc. The scores of both thermal sensation and thermal comfort were reduced significantly immediately after the start of fanning, and their time courses were different to those of Ts and Tty. These results support previous reports that thermal sensation depends on skin temperature, and that thermal comfort depends on both the skin and core temperatures. Moreover, they indicate that both thermal sensation and comfort ratings are affected by the dynamic responses of the cutaneous thermoreceptors when fanning is applied to the face during hyperthermia.

Clinical features of a polymorphism of the beta3-adrenergic receptor gene in patients with type 2 diabetes mellitus--a study using a pin-point sequencing method.

UNLABELLED: The human beta(3)-adrenergic receptor (beta(3)AR) is expressed specifically in adipose tissues, and its activation is activated in brown adipose tissues during thermogenesis and in white adipose tissues during lipolysis. We investigated the relationship between a polymorphism of the beta(3)AR gene and the clinical features of type 2 diabetes mellitus. Studies were conducted in 30 type 2 diabetic patients (15 males and 15 females). Analysis of polymorphisms of the beta(3)AR gene was performed by a pin-point sequencing method using the hair of the subjects. Preperitoneal (P-fat) and subcutaneous fat (S-fat) levels were determined by ultrasonography. We found a Trp(64)Arg allele of the beta(3)AR gene in the hair of 27% of all patients. The patients with this mutation showed a significantly younger onset-age of diabetes than those of the wild type. The body mass index, serum GPT levels, fasting immunoreactive insulin (IRI) and daily urinary C-peptide reaction (CPR) in the mutation group were markedly higher than in the wild type group. The P-fat, serum cholesterol and leptin concentrations tended to be higher in the mutation group. Patients in the mutation group had a significantly higher prevalence of hypertension (80%) compared with those in the wild type group (20%). CONCLUSIONS: The present results suggest that the clinical features of diabetic patients with a missense mutation in the beta(3)AR gene are substantially distinct from those of the wild type patients. These specific features include obesity, hyperinsulinemia, hypertension, and an increase in preperitoneal fat.

Molecular analysis of constitutive IL-1alpha gene expression in human melanoma cells: autocrine stimulation through NF-kappaB activation by endogenous IL-1alpha.

Constitutive production of/and acquired resistance to anti-proliferative cytokines are implicated in pathogenesis and progression of human melanoma cells. Human melanoma cells A375-C6 are sensitive to interleukin 1 (IL-1) anti-proliferative effect and do not produce IL-1. After long period of culture we have obtained cells which acquired resistance to IL-1. The resistant cells exhibited constitutive production of IL-1α. To analyse the mechanisms that lead to the expression of IL-1α in the cells, we transfected of the resistant clone A375-R8 with CAT (chloramphenicol acetyltransferase) expression plasmids linked to a 5'-flanking deletion mutants of the human IL-1α gene. Two nucleotide regions (--103 to --70 bp) and (--70 to --47 bp) from the start of the first exon appeared to contain a positive regulatory element(s) while the one --421 to --103 bp contained a negative regulatory element(s).The --103 to --70 bp region contained the consensus NF(-k)B (nuclear factor-kB) binding motif.(Immunofluorescence analysis revealed that NF-kB is activated in A375-R8 cells. IL-1 receptor antagonist (IL-1Ra) decreased the level of IL-1α mRNA and production of IL-1α. IL-1Ra also inhibited the localization of p65 in the nuclei and CAT activity in transfectants with the plasmids containing NF-kB binding motif. These results indicate that endogenous IL-1α stimulates the gene expression and production of IL-1α in an autocrine manner through activation of NF-kB.

Interleukin-1-induced growth inhibition of human melanoma cells. Interleukin-1-induced antizyme expression is responsible for ornithine decarboxylase activity down-regulation.

Interleukin (IL)-1 is a multi-functional cytokine and regulates cell growth either positively or negatively. Previous studies have shown that IL-1-induced ornithine decarboxylase (ODC) activity down-regulation is involved in the anti-proliferative effect of IL-1 on human A375 melanoma cells. In this study, we examined the IL-1alpha-induced molecular events resulting in ODC activity down-regulation in C2-1, a A375 cell line stably transfected with human type I IL-1 receptor. Recombinant human (rh) IL-1alpha inhibited the growth and down-regulated the ODC activity of C2-1 cells in a dose-dependent manner. Kinetics studies showed that both the DNA synthesis and ODC activity of C2-1 cells progressively decreased from 12 h after IL-1 addition. Northern hybridization showed that IL-1 had no influence on ODC mRNA level. However, rhIL-1 induced both a decrease of ODC protein and an ODC-inhibiting activity in IL-1-treated C2-1 cells. IL-1 specifically up-modulated the mRNA level of antizyme, a protein essential for ODC regulation, but had little effect on its stability. IL-1-induced antizyme up-modulation preceded IL-1-induced down-regulation of ODC protein, ODC activity, and DNA synthesis in C2-1 cells. Run-on transcription analysis confirmed that the increased antizyme mRNA expression was due to elevated antizyme gene transcription. Furthermore, the action of IL-1 to inhibit the ODC activity and growth of C2-1 cells was blocked by expressing the antisense RNA of human antizyme in C2-1 cells. These results suggest that IL-1-induced antizyme expression is responsible for IL-1-induced ODC activity down-regulation in human melanoma cells.

Error analysis of autoradiography method for measurement of cerebral blood flow by 123I-IMP brain SPECT: a comparison study with table look-up method and microsphere model method.

N-isopropyl-p-[123I]iodoamphetamine (IMP) has been commonly used as a cerebral blood flow tracer, but, significant clearance of IMP from the brain to the blood causes underestimation of cerebral blood flow (CBF) as compared with true CBF when the conventional microsphere model method is applied. Previously, we reported an "Autoradiography method" (ARG method) for measuring CBF by using IMP in which this clearance effect was corrected. This method was based on a two-compartment model (influx: K1, efflux: k2, K1/k2 = distribution volume of IMP (Vd)), the K1 (corresponding to CBF) being obtained form the table which showed a correlation between CBF and the brain counts of SPECT scan with a constant Vd value. Arterial input data used were obtained by one point blood sampling 10 min after IMP infusion against the standard input function. In the present study, the ARG method was compared with the table look-up method (TLU method) and the conventional microsphere model method (MS method) for 30 subjects. When the Vd value in the ARG method was assumed to be 50 ml/ml, CBF values obtained by the ARG method were correlated well with those obtained by the TLU method (Y = 1.04X-2.5; X: TLU, Y: ARG r = 0.97) and those obtained by the MS method (Y = 0.82X + 12.1; X: ARG, Y: MS, r = 0.84). But, when the Vd value was assumed to be more or less than 50 ml/ml, ARG method CBF were under- or overestimated compared with the TLU method. This indicated that the ARG method could be a reliable method for CBF measurement if the Vd was determined properly. CBF values obtained by the MS method were actually 13.2% higher than those obtained by the ARG method against previous studies. As reasons for this, errors in the effects of gray-white matter mixture in the ARG method and in estimation of the SPECT brain counts at 8 min in the MS method were considered.

[A simple method for measurement of cerebral blood flow using 123I-IMP SPECT with calibrated standard input function by one point blood sampling; validation of calibration by one point venous blood sampling as a substitute for arterial blood sampling].

In a simplified method for measurement of cerebral blood flow using one 123I-IMP SPECT scan and one point arterial blood sampling (Autoradiography method), input function is obtained by calibrating a standard input function by one point arterial blood sampling. A purpose of this study is validation of calibration by one point venous blood sampling as a substitute for one point arterial blood sampling. After intravenous infusion of 123I-IMP, frequent arterial and venous blood sampling were simultaneously performed on 12 patients of CNS disease without any heart and lung disease and 5 normal volunteers. The radioactivity ratio of venous whole blood which obtained from cutaneous cubital vein to arterial whole blood were 0.76 +/- 0.08, 0.80 +/- 0.05, 0.81 +/- 0.06, 0.83 +/- 0.11 at 10, 20, 30, 50 min after 123I-IMP infusion, respectively. The venous blood radioactivities were always 20% lower than those of arterial blood radioactivity during 50 min. However, the ratio which obtained from cutaneous dorsal hand vein to artery were 0.93 +/- 0.02, 0.94 +/- 0.05, 0.98 +/- 0.04, 0.98 +/- 0.03, at 10, 20, 30, 50 min after 123I-IMP infusion, respectively. The venous blood radioactivity was consistent with artery. These indicate that arterio-venous difference of radioactivity in a peripheral cutaneous vein like a dorsal hand vein is minimal due to arteriovenous shunt in palm. Therefore, a substitution by blood sampling from cutaneous dorsal hand vein for artery will be possible. Optimized time for venous blood sampling evaluated by error analysis was 20 min after 123I-IMP infusion, which is 10 min later than that of arterial blood sampling.

Ascorbic acid deficiency decreases specific forms of cytochrome P-450 in liver microsomes of guinea pigs.

Ascorbic acid (VC) deficiency resulted in a decrease in the activities of aminopyrine N-demethylase, aniline hydroxylase, and p-nitroanisole O-demethylase and in the content of cytochrome P-450, as spectrally determined, whereas it caused an increase in the activities of 6 beta-hydroxylases for testosterone and progesterone in liver microsomes of guinea pigs. Western blot analysis of liver microsomes with antibodies to rat P-448-H (P-4501A2), P-450j (P-450IIE), P-450 PB-1 (P-450IIIA), and P-450b (P-450IIB1) showed that VC deficiency decreased the amount of cytochrome P-450 immunochemically related to P-450IA2 and P-450IIE but did not change the amount of the form that was cross-reactive with antibodies to P-450IIB1 and tended to slightly increase (not statistically significantly) the amount of the form of the cytochrome immunochemically related to P-450IIIA. The larger decrease by VC deficiency in the amount of cytochrome P-450 that was cross-reactive to the rat P-450IA2 resulted in a lower capacity of liver microsomes to activate promutagens, such as 2-amino-3-methyl-imidazo(4,5-f)quinoline and aflatoxin B1. These results indicate that VC deficiency in guinea pigs differentially affects the content of individual forms of cytochrome P-450.