Kuniyasu Soda

Polyamine-rich food decreases age-associated pathology and mortality in aged mice.

The purpose of this study was to test whether oral intake of foods rich in polyamines (spermine and spermidine) suppresses age-associated pathology in aged mice. Synthetic polyamines were mixed into experimental chows, and 24-week-old Jc1:ICR male mice were fed one of three chows containing differing polyamine concentrations. The spermine and spermidine concentrations in the low, normal, and high polyamine chows were 143 and 224 nmol/g, 160 and 434 nmol/g, and 374 and 1540 nmol/g, respectively. An increase in concentration of polyamine in the blood was found only in mice fed the high polyamine chow at 50 weeks of age. While the body weights of mice in all three groups were similar, the survival rate of mice fed high polyamine chow was significantly higher than those in the other two groups (p=0.011). Mice fed the high polyamine chow analyzed at 88 weeks of age, corresponding to the end of the study, demonstrated lower incidence of glomerulosclerosis and increased expression of senescence marker protein-30 in both kidney and liver compared to those fed the low polyamine chow. As these pathological changes are associated with senescence, oral polyamine appears to inhibit the progression of age-associated pathologies.

Spermine, a Natural Polyamine, Suppresses LFA-1 Expression on Human Lymphocyte

Natural polyamines, spermine, spermidine, and putrescine, play a pivotal role in the regulation of gene expression; therefore, the age-dependent decreases and the disease-dependent increases in polyamine synthesis suggest a possible contribution of polyamines to the age-related and disease-associated changes in cellular function. In this study, we examined the effects of polyamines on the cellular function and the expression of adhesion molecules on human PBMCs from healthy volunteers. Flow cytometry revealed that PBMCs cultured with spermine decreased mean fluorescent intensities (MFIs) of CD11a and CD18 in the lymphocyte light-scattered region, but not in the monocyte region. This suppression was observed in a dose- and time-dependent manner and found nonspecifically on all cell subsets we tested (CD3+, CD4+, CD8+, CD19+, CD45RA+, CD45RO+, CD4+CD45RA+, CD4+CD45RO+, CD8+CD45RA+, CD8+CD45RO+). The decreases of CD11a and CD18 MFIs were accompanied by the decrease in adherent capacity of PBMCs to HUVECs. Spermine did not hinder cell activities or cell viability. Among 42 healthy volunteers (mean, 49.5 years old; from 26 to 69), blood spermine levels inversely correlated with the CD11a MFIs of cells in the lymphocyte region (r = −0.48; p = 0.001), but not with those in the monocyte region. The effects of spermidine seemed weaker than those of spermine, and blood spermidine levels had no correlation with CD11a MFIs of the lymphocyte region. Putrescine had no effect on the expressions of membrane molecules. Polyamines, especially spermine, decrease LFA-1 (CD11a/CD18) expression on human lymphocyte and adhesion capacity of PBMCs to HUVECs.

Characterization of Mice Bearing Subclones of Colon 26 Adenocarcinoma Disqualifies Interleukin-6 as the Sole Inducer of Cachexia

A snbclone (clone 20) of chemically induced, marine colon adcnocarcinoma with a potent ability to induce cachexia and another subclone (clone 5) without such an activity were transplanted to syngeneic mice (CDFi) and their tissue weights, blood components and cytokine levels in sera were compared. Mice transplanted with clone 20 showed a profound body‐weight loss by 15 days after inoculation when the tumor accounted for less than 1% of the body weight, along with marked reduction of food and water intakes. Thereafter, they transiently gained in body weight with restoration of food and water intakes. Thus, the change in body weight was biphasic and not proportional to the tumor size. Body fat was lost preferentially, accompanied with a decrease in plasma triglyceride levels. The thymus contracted remarkably, and the peripheral lymphocyte count decreased extensively. Mice transplanted with clone 5, in contrast, did not show any of these changes characteristic of cachexia. Serum concentration of interleukin‐6, which has been proposed as the principal inducer of cachexia in mice with colon 26, increased in mice with clone 5 to levels comparable to those in mice with clone 20. The changes in mice hearing clone 20 could not all be explained in terms of known biological activities of interleukin‐6. Additional unknown factors, therefore, are presumed to contribute to cachexia in mice with clone 20. Identification of them should be helpful in the care of cachectic patients.

Polyamine intake, dietary pattern, and cardiovascular disease

In addition to general lifestyle, a number of foods and dietary patterns, such as the Mediterranean diet (MD), are associated with lower incidences of chronic, age-related diseases, and mortality. We have shown that increased polyamine intake decreases age-associated pathology and increases longevity in mice. Several foods in the MD, such as fruits and legumes, are foods containing high amount of polyamines. Among age-associated conditions, cardiovascular diseases (CVD) are the leading cause of mortality worldwide, and individuals who adhere to a MD have a lower incidence of CVD. The possible contribution of increased polyamine intake to CVD prevention is discussed in this manuscript. Polyamines from food are distributed to all organs and tissues, and long-term intake increases polyamine concentration in blood. Because most polyamines are associated with red and white blood cells, they act to suppress synthesis of pro-inflammatory cytokines and of leukocyte function-associated antigen-1. Foods with anti-inflammatory properties such as n-3 polyunsaturated fatty acids are known to help prevent CVD. Additionally, suppression of de novo polyamine synthesis results from increased polyamines intake, normally synthesized from arginine. This in turn increases availability of arginine for synthesis of nitric oxide, which plays an important role in preserving normal vascular physiology.

Increased Polyamine Intake Inhibits Age-Associated Alteration in Global DNA Methylation and 1,2-Dimethylhydrazine-Induced Tumorigenesis

Polyamines (spermine and spermidine) play many important roles in cellular function and are supplied from the intestinal lumen. We have shown that continuous high polyamine intake inhibits age-associated pathologies in mice. The mechanism by which polyamines elicit these effects was examined. Twenty-four week old Jc1:ICR male mice were fed one of three experimental chows containing different polyamine concentrations. Lifetime intake of high polyamine chow, which had a polyamine content approximately three times higher than regular chow, elevated polyamine concentrations in whole blood, suppressed age-associated increases in pro-inflammatory status, decreased age-associated pathological changes, inhibited age-associated global alteration in DNA methylation status and reduced the mortality in aged mice. Exogenous spermine augmented DNA methyltransferase activity in Jurkat and HT-29 cells and inhibited polyamine deficiency-induced global alteration in DNA methylation status in vitro. In addition, increased polyamine intake was associated with a decreased incidence of colon tumors in BALB/c mice after 1,2-demethylhydrazine administration; 12 mice (60%) in the low polyamine group developed tumors, compared with only 5 mice (25%) in the high polyamine group (Fishers exact probability = 0.027, p = 0.025). However, increased polyamine intake accelerated the growth of established tumors; maximal tumor diameter in the Low and High groups was 3.85±0.90 mm and 5.50±1.93 mm, respectively (Mann-Whitney test, p = 0.039). Spermine seems to play important roles in inhibiting age-associated and polyamine-deficient induced abnormal gene methylation as well as pathological changes including tumorigenesis.

Mediterranean diet and polyamine intake: possible contribution of increased polyamine intake to inhibition of age-associated disease

The Mediterranean diet is a dietary pattern associated with increased longevity, and has been shown to have anti-inflammatory properties. Based on the findings that natural polyamines are strong anti-inflammatory substances, we have found that continuous and increased polyamine intake prolongs murine lifespan. Because polyamines are contained in most foods in widely varying concentrations, we sought epidemiologic evidence that supports an association between the Mediterranean diet and increased polyamine intake. The amounts of food supply in 49 European and other Western countries in 2005 were collected from the United Nations database, and the amount of food polyamine was estimated using polyamine concentrations in foods from published sources. The Mediterranean diet pattern was characteristically observed in Mediterranean countries. For all 49 countries and for foods such as olive oil (Spearman r = 0.602), fruit (r = 0.804), fruit and vegetables (r = 0.611), seafood (r = 0.461), and cheese (r = 0.411), the ratios of the amounts of these foods to total calories consumed were all posi- tively associated (P , 0.05) with the amount of polyamine per calorie. Legumes per calorie (r = 0.379), wine per calorie (r = 0.285), and the amount of seafood and poultry meat relative to red meat (r = 0.313) had a trend of positive association with the amount of polyamine per calorie (P , 0.05), while several foods in the non-Mediterranean diet group had a trend of no or negative association. Food polyamines are absorbed quickly from the intestinal lumen, and long-term increased polyamine intake increases blood polyamine concentration. The present findings, together with previous studies on polyamines, indicate a possible role for the food polyamines that are abundant in the Mediterranean diet in prolonging human life.

Spermine accelerates hypoxia-initiated cancer cell migration

Polyamine levels are elevated in the organs and tissues of cancer patients due to increased synthesis and active intercellular transport in cancer cells. Because increased polyamine levels are associated with poor prognosis, the effect of polyamines on the malignant potential of cancer cells was investigated. Highly metastatic colon cancer cells (HT-29) were cultured under either normoxia (21% O2) or hypoxia (2% O2) for 48 h with 0, 100, or 500 µM spermine, one of the natural polyamines with the strongest biological activity. Spermine supplementation ameliorated MTT metabolism of hypoxic cancer cells in a dose-dependent manner, but had no effect on cells cultured under normoxia. Hypoxia decreased cancer cell CD44 and E-cadherin expression, while CD44 expression further decreased by spermine in a dose-dependent manner. By comparing cells cultured under normoxia with increasing amounts of spermine, we found that CD44 expression decreased by 11% (0 µM spermine), 14% (100 µM), and 18% (500 µM), and was accompanied by comparable decreases in CD44 mRNA levels. Martigel invasion assay showed that hypoxia increased the number of invading cells, and spermine further enhanced the hypoxia-induced increase in the number of invading cells in a dose-dependent manner. The numbers of invading cells cultured with 0, 100, and 500 µM spermine under hypoxia were 2.3, 2.8, and 3.2 times greater, respectively, compared to cells with 0 µM spermine under normoxia. Increased extracellular spermine enhances the invasion potential of cancer cells under hypoxia.

Splenectomy before tumor inoculation prolongs the survival time of cachectic mice

The effects of splenectomy on the development of cachexia, tumor growth and animal survival were studied in tumor-bearing CDF1 mice. Mice were inoculated with two subclones of colon 26 adenocarcinoma, clone 20 (with a potent capacity to induce cachexia) and clone 5 (without such activity), and underwent splenectomy before or after tumor inoculation. Splenectomy significantly prolonged the survival of mice bearing clone 20 when it was performed prior to tumor inoculation, although the progression of cachexia and tumor growth were not affected. The survival rate was higher in splenectomized than it was in nonsplenectomized mice 20–40 days after tumor inoculation. Such effects on survival were not observed, however, in mice splenectomized after inoculation with clone 20 or in mice that underwent splenectomy either before or after inoculation with clone 5. The decrease of peripheral blood lymphocyte count observed in mice bearing clone 20 was magnified when splenectomy was performed before tumor inoculation, but the serum levels of tumor necrosis factor and interleukin-6 were comparable. These results indicate that cancer death from cachexia is not directly attributable to enhanced catabolism. The mechanism by which splenectomy ameliorates the survival of cachectic mice remains to be studied, although several changes observed in the splenectomized mice after inoculation, including decreases in the peripheral blood L3T4+ cells and Lyt-2+ cells on the 9th day and 15th day respectively, and increase in the L3T4+/Lyt-2+ cell ratio on the 15th day suggest the involvement of the modified hosts immune response.

Biclonal extramedullary plasmacytoma arising in the peritoneal cavity: report of a case.

We report a rare case of extramedullary plasmacytoma, which arose either in the ileum or the ileal mesentery. A 70-year-old woman presented with a high fever and symptoms of bowel obstruction. Computed tomography and magnetic resonance imaging showed a large heterogeneous tumor in the peritoneal cavity. Serum immunoelectrophoresis revealed a biclonal increase of IgA-Κ and IgG-Κ. At surgery, we found that the parenchyma of the fragile tumor had firm communication with the ileal mesentery, and the cavity of the tumor communicated with the ileal lumen. After a temporary regression following surgery and chemotherapy, the tumor grew rapidly. Although there was no evidence of progression to multiple myeloma, the patient died of cachexia less than 4 months after surgery.

Suppression of LFA-1 Expression by Spermine Is Associated with Enhanced Methylation of ITGAL, the LFA-1 Promoter Area

Spermine and spermidine, natural polyamines, suppress lymphocyte function-associated antigen 1 (LFA-1) expression and its associated cellular functions through mechanisms that remain unknown. Inhibition of ornithine decarboxylase, which is required for polyamine synthesis, in Jurkat cells by 3 mM D,L-alpha-difluoromethylornithine hydrochloride (DFMO) significantly decreased spermine and spermidine concentrations and was associated with decreased DNA methyltransferase (Dnmt) activity, enhanced demethylation of the LFA-1 gene (ITGAL) promoter area, and increased CD11a expression. Supplementation with extracellular spermine (500 µM) of cells pretreated with DFMO significantly increased polyamine concentrations, increased Dnmt activity, enhanced methylation of the ITGAL promoter, and decreased CD11a expression. It has been shown that changes in intracellular polyamine concentrations affect activities of -adenosyl-L-methionine-decaroboxylase, and, as a result, affect concentrations of the methyl group donor, S-adenosylmethionine (SAM), and of the competitive Dnmt inhibitor, decarboxylated SAM. Additional treatments designed to increase the amount of SAM and decrease the amount of decarboxylated SAM–such as treatment with methylglyoxal bis-guanylhydrazone (an inhibitor of S-adenosyl-L-methionine-decaroboxylase) and SAM supplementation–successfully decreased CD11a expression. Western blot analyses revealed that neither DFMO nor spermine supplementation affected the amount of active Ras-proximate-1, a member of the Ras superfamily of small GTPases and a key protein for regulation of CD11a expression. The results of this study suggest that polyamine-induced suppression of LFA-1 expression occurs via enhanced methylation of ITGAL.