The effect of fasting and refeeding on thyroid follicule structure and thyroid hormone levels in young and old rats

In order to assess morphological and functional plasticity of the thyroid gland in aging the effects of fasting and refeeding on the thyroid morphology and thyroid hormone serum levels were compared with morphometry and RIA in young and old rats. Young (4 months) and old (24 months) male Wistar rats were fasted for 40 h and sampled, or fasted and fed thereafter for 4 or 24 h. In control (fed) old animals the thyroid follicules were larger, the follicular epithelium was smaller and colloid resorption was smaller than in young rats. 'Thyroid activation index' (epithelial volume/colloid volume ratio) was almost twice lower in the thyroids of control old rats. As the result of fasting, height, surface area and volume of epithelial follicular cells decreased in the thyroids of fasted young rats but not in old ones. On the contrary, in thyroids of fasted old rats the dimensions of epithelial cells did not change and thyroid colloid resorption was increased. After 24 h of refeeding, thyroid morphology in both young and old rats did not differ significantly as compared with control animals. Upon fasting, serum levels of thyroxine (T4) and triiodothyronine (T3) decreased by 28 and 38% in young and by 35 and 46% in old rats, respectively. However, T4 and T3 serum concentrations did not differ significantly between age groups in both fed and fasted states. During refeeding the increase in serum thyroxine concentration was delayed in old rats as compared with young ones. The results of morphological, morphometric and hormonal investigations indicate the existence of age-related changes in the structure and function of thyroid follicular cells.

Immunomodulatory properties of new conjugates of muramyl dipeptide and nor-muramyl dipeptide with retro-tuftsin (Arg-Pro-Lys-Thr-OMe)

Six new conjugates of muramyl dipeptide and nor-muramyl dipeptide with retro-tuftsin were synthesised at Gdansk University of Technology. All compounds were investigated at Medical University of Gdansk. Their immunomodulatory properties were assessed using in vitro cultures of human subpopulations of white blood cells (peripheral blood mononuclear cells, peripheral blood lymphocytes, monocytes). We examined the viability of blood cells incubated with examined conjugates, as well as their ability to stimulate secretion of cytokines (TNFalpha--tumour necrosis factor alpha, IL6--interleukin 6) and cytotoxic activity of NK (Natural Killer) cells. Complementation in biological activity of muramyl dipeptide (MDP) and tuftsin in conjugates proved to be beneficial in the field of immunoadjuvanticity. Our investigations proved that new conjugates acquired features that native immunomodulators did not reveal separately. In examined compound, the part responsible for inducing cytotoxic activity of NK cells was the tuftsin part of the conjugates. MDP in conjugates was responsible for compound-induced synthesis of TNFalpha. The results of our study imply usefulness of the examine compounds (mainly A and B), as potential therapeutic agents.

Biological activity of conjugates of muramyl dipeptides with batracylin derivatives

Antitumour activity of batracylin (BAT), muramyldipeptide (MDP) and four immunomodulatory conjugates of BAT with MDP were evaluated in the study. The activity was assessed using viability tests performed in the cultures of tumour cell lines of different tissue origin such as WEHI 164 (fibrosarcoma), K562 (leukaemia), and Ab (melanoma), populations of immune cells isolated from peripheral blood, and the tumour cells mixed with immune cells. An intensity of cell death caused by the analogues was measured using flow cytometry analysis as subG1 peak and the distinction between necrotic and apoptotic DNA cleavage during cell death was performed using DNA fragmentation assay. The compounds 11c, 11e and 11h managed to kill WEHI 164 cells in the presence of immune cells in apoptotic manner while BAT and conjugate 11a caused necrosis at the same time. Necrotic pattern of DNA cleavage was also noted in all cultures containing K562 and Ab cells. BAT and MDP caused necrosis in the cultures of pure immune cells, while the conjugates did not affect these cultures at all. Surprisingly, some analogues increased viability of K562 and Ab cells. Low toxicity and ability to induce apoptosis suggested usefulness of some analogues, mainly 11c, as antitumour drugs in limited range of tumours of certain tissue origin, such as WEHI 164.

High levels of circulating interleukin-10 in diabetic nephropathy patients

AIMS

The aim of our study was to analyse the level of circulating interleukin-10 (IL-10) and relate it to the grade of albuminuria in patients with diabetic nephropathy (DN) due to type 1 diabetes mellitus (DM). Since IL-10 has met the criteria for an anti-inflammatory and an immunosuppressive cytokine, its activity may be important for clinical outcome of DN.

METHODS

The IL-10 level was measured by ELISA in serum samples from thirty patients with DN due to type 1 DM, and compared with thirty patients with type 1 DM without DN and a control group of thirty, healthy, age- and sex-matched people.

RESULTS

We observed a greatly elevated concentration of circulating IL-10 in 30/30 DM patients with DN (mean 140 pg/mL +/- 102), compared to DM patients without DN in whom IL-10 was detectable in only 11/30 patients (0.79 pg/mL +/- 1.24), and the group of healthy people in whom IL-10 was detectable in only 3/30 donors (0.92 pg/mL +/- 0.17). IL-10 appeared to be the strongest independent predictor of albuminuria, followed by HbA1c, diastolic blood pressure and DN duration. There was a positive correlation between the values of IL-10 and albuminuria in DM patients with DN. The patients in the fourth quartile of albuminuria had a distinctly higher concentration of IL-10 than those in the lower quartiles.

CONCLUSIONS

The increased concentration of IL-10 in the serum samples from DM patients with DN seems to depend on the severity of the nephropathy. The excessive IL-10 production may indirectly contribute towards DN progression. On the other hand, it may explain the relatively long course of diabetic nephropathy.

Level of NK cytotoxic activity in the elderly aged more than 80 years

A group of healthy volunteers aged 60-93 years, was evaluated with respect to their NK activity. These people have been under careful medical observation for 3 years and were selected according to Senieur Protocol criteria. NK activity of each person was checked at least three times at regular 12-month intervals with the chromium release test and twice at the same interval of time with a single cell cytotoxicity assay. NK activity of 60-79-year-old females was in a similar range of values as that of young females (20-35 years) and was lower than that of the males of the corresponding age groups. The females aged 80-88 years revealed the highest NK activity. The chronically ill 80-88-year-old females, on the other hand, were characterized by a marked decrease of NK activity in relation to their age counterparts. NK activity of both the females and males significantly declined at the age of 89-93 years. The significance of NK activity for survival is discussed.

Synthesis and biological activity of tuftsin, its analogue and conjugates containing muramyl dipeptides or nor-muramyl dipeptides

Several conjugates of muramyl dipeptide (MDP) or nor-muramyl dipeptide (nor-MDP) with tuftsin were synthesized. Conjugates 8a-f were prepared by acylation of protected tuftsin with the isoglutamine carboxyl group of MDP or nor-MDP 2a-f. Also tuftsin analogue 6 (H-Thr-Lys-Pro-Arg(NO2)-OH) was obtained. All synthesized compounds were investigated at the Medical University of Gdansk. The biological activity of the examined compounds was estimated using in vitro cultures of human monocytes and lymphocytes. The substances displayed cytotoxic effects, as was revealed in the viability tests performed. The effects were most probably mediated by the induction of an oxidative burst in monocytes and the stimulation of redox enzymes in lymphocytes. In addition, the analogues turned out to be efficient stimulators of TNFalpha and IL6 secretion by monocytes and lymphocytes. Nevertheless, the secretion of cytokines did not affect the viability of the leukocyte population used in the experiments.The beneficial properties of the compounds examined (mainly 6, 3, 8a and 8c), which implies their usefulness as potential therapeutic agents, are connected with their rapid start of action and more efficient effects compared with tuftsin alone. An in vivo assay on animal models will be performed.

Immunomodulating effect of influenza vaccination in the elderly differing in health status

The aim of this study was to analyse whether split influenza vaccine may elicit NK cytotoxic response in the vaccinated elderly people and whether this effect may be maintained over few weeks after vaccination. It was also worth investigating the relation between NK activity in the vaccinated and specific immune protection against influenza and non-specific against other infections. Two groups of volunteers were vaccinated with trivalent split viron influenza vaccine in two consecutive seasons (1999/2000; 2000/2001). The elderly group consisted of 142 people (65-92 years old) in the first season and 110 in the second; while the young (16-44 years old) of 98 and 67 people, respectively. An analysis of NK cytotoxic activity had been done before vaccination, two days, one month and fifth months thereafter. The results revealed that vaccination with the influenza vaccine had an augmenting effect on NK activity, in all groups examined, in both epidemic seasons, visible at two days and 1 month after the vaccination. In the elderly high pre- and post-vaccination NK activity was related to higher titers of anti-hemagglutinin, better health status and lower incidence of all cause respiratory tract infections. At the second vaccination, most of the elderly with chronic medical conditions and high NK activity, who did not attain the protective level of anti-hemagglutinins in the first season, converted into the protected. High pre- and post-vaccination NK activity predisposes elderly people to the protective humoral anti-hemagglutinin response and gives better protection from respiratory tract infections.

Complete remission of Bomirski Ab amelanotic melanoma in hamsters treated with the angiogenesis inhibitor TNP-470

The growth of solid tumors and their metastasis is dependent on the development of new blood vessels (angiogenesis). In our previous studies it was found that angiogenesis inhibitor TNP-470 acting systematically can decrease the rate of growth of transplantable Bomirski Abmelanoma in hamsters. In this study we applied TNP-470 (30 mg/kg) peritumorally from the day when tumor was palpable over 10 days, once daily. Animals were killed 6 months later and examination by autopsy and histological preparations showed the complete remission of transplanted tumor and the lack of metastasis. Thus, Ab melanoma can be effectively cured with TNP-470 angiogenesis inhibitor when the substance is applied locally.

Thyroid C cell function during fasting and refeeding of young and old rats

Age-related alterations in the structure and function of many organs often become apparent under stimulation of their function. Although the ageing process affects the regulation of mineral homeostasis, the function of thyroid C-cells that secrete calcitonin (CT) under the conditions of fasting and refeeding, a way of dietary manipulation that reveal the existence of age-related changes of follicular thyroid cells, has not been characterized. Therefore, we investigated the number of C-cells and serum CT concentration in young (4 mo) and old (26 mo) male rats fasted for 48 hours, and then refed for 4 or 24 hours. We found significantly higher number of C-cells in thyroids of old vs young rats both under basal conditions, and after fasting/refeeding. Correspondingly, serum calcitonin level was higher in fed or fasted old rats vs young ones. However, in young rats refeeding decreased, whereas in old animals increased serum concentrations of calcitonin. Thus, the control of serum calcium concentration, that was well preserved in old rats, occurs at the expense of increased serum CT level both under basal conditions, and after refeeding. These observations suggest that C-cell function is altered in ageing.

The effect of short G-CSF administration on the numbers and clonogenic efficiency of hematopoietic progenitor cells in bone marrow and peripheral blood of normal donors

We have analysed the cellularity, the number of clonogenic cells and their clonogenic efficiency (the number of clonogenic cells/2 x 10(5) MNC) in peripheral blood (PB) and bone marrow (BM) during and after filgrastim (rhG-CSF) mobilization of CD34+ cells in 12 healthy donors for allogeneic stem cell donation. G-CSF was administrated subcutaneously for 5 consecutive days at a dose of 10 micrograms/kg/day. WBC, MNC, CD34+ cell counts, CFU-GM and BFU-E assays in PB were performed at baseline and then daily 12 hours after each G-CSF dose. BM was assayed before start (day 1) and after the last dose (day 6) of G-CSF. Results are given as medians, with ranges in parentheses. In PB the total WBC and MNC increased 7.4-fold (6.0-12.3) and 3.3-fold (1.5-9.4), respectively, reaching a peak of 49.4 x 10(9)/l (32.5-66.6) on day 6 for WBC and 6.28 x 10(9)/l (4.7-13.3) for MNC on day 5. CD34+ cell number reached a peak value of 48.0 x 10(6)/l (45.6-285) on day 6 whereas CFU-GM and BFU-E reached their peaks on day 5, 0.95 x 10(4)/ml (0.05-6.08) and 1.04 x 10(4)/ml, respectively. CFU-MIX, not detectable at baseline, reached a peak of 0.95 x 10(4)/ml (0.006-0.51) on day 5 as well. This was accompanied by an increase in CFU-GM, BFU-E and CFU-MIX clonogenic efficiency: 23-fold (3-150), 9.75-fold (2.2-27.8) and 20-fold (2.5-210), respectively. In BM the total WBC number increased 2.5-fold (1.3-4.9) from the baseline value of 52.6 x 10(9)/l (7.9-137.0) whereas the MNC count increased 2.0-fold (0.81-3.7) from a baseline of 13.6 x 10(9)/l (3.5-54.8). This was, however, not significant. The number of CD34+ cells increased significantly 2.9-fold (0.8-8.3). In 8 donors CFU-MIX were detectable before but not after G-CSF treatment. A similar decrease in CFU-GM and BFU-E clonogenic efficiency occurred but was not significant. CFU-GM and BFU-E numbers did not change. We conclude that the total body numbers of lineage committed progenitors increased during G-CSF administration, which indicate their proliferation in addition to mobilization. The effect of G-CSF on the number of more primitive progenitors in BM is less clear and needs further investigation.

Effects of oestrogen deprivation on interleukin-6 production by peripheral blood mononuclear cells of postmenopausal women

Various hormones can influence the expression of interleukin-6 (IL-6) and oestrogens are the most extensively studied. There is, however, controversy about the nature of the IL-6 secreted by human cells and its regulation by 17beta-oestradiol. The aim of this work was to clarify whether oestrogen deprivation after menopause may contribute to an enhanced IL-6 production by peripheral blood mononuclear cells (PBMC) in postmenopausal women. Twenty-two healthy postmenopausal women, age range 45-63 years, with clinical symptoms of oestrogen deficiency were enrolled in the study. The control group consisted of 16 healthy young women, age range 22-31 years, with regular menses and who were not taking oral contraceptives. Levels of IL-6 in the sera and PBMC culture supernatants were measured by the biological B9 cell-proliferation assay and expression of the IL-6 gene in non-stimulated PBMC was detected by RT-PCR. The effect of 17beta-oestradiol on spontaneous IL-6 production by the PBMC of postmenopausal women was also studied in vitro and in vivo. Seventeen out of the twenty-two postmenopausal women were given hormonal replacement therapy of 50 microg 17beta-oestradiol/day transdermally and the spontaneous production of IL-6 by the PBMC was analysed after 6 and 12 months of treatment. The postmenopausal women had significantly higher serum levels of IL-6 than the young controls. The spontaneous production of IL-6 by non-stimulated PBMC into the culture supernatants was also significantly higher in the postmenopausal women compared with the young. We also found that IL-6 gene expression was present in the non-stimulated PBMC isolated directly from the venous blood of the majority of the postmenopausal women. Women with IL-6 gene expression in the non-stimulated PBMC had significantly lower serum levels of 17beta-oestradiol compared with those where the IL-6 gene was not expressed in the PBMC. Our in vitro experiments showed that 17beta-oestradiol at concentrations of 10(-9) M and 10(-10) M decreased spontaneous IL-6 production by the PBMC of postmenopausal women. In vivo treatment with 17beta-oestradiol transdermally also significantly decreased spontaneous IL-6 production by the PBMC of postmenopausal women after 12 months of the therapy. Our results indicate that oestrogen deprivation after menopause may enhance IL-6 production by the PBMC of postmenopausal women. We suspect that the late complications of oestrogen deficiency, such as osteoporosis, coronary heart disease and Alzheimer's disease, may be mediated by an exaggerated production of IL-6 - a cytokine which seems to play a pivotal role in the pathogenesis of these age-related diseases.

Synthesis and antitumor activity of conjugates of muramyldipeptide, normuramyldipeptide, and desmuramylpeptides with acridine/acridone derivatives

The synthesis of two groups (Chart 1, types A and B) of conjugates of MDP (muramyldipeptide) and nor-MDP (normuramyldipeptide) with acridine/acridone derivatives and the synthesis of analogues of desmuramylpeptides (Chart 1, types C and D) containing acridine/ acridone derivatives have been described. In type A conjugates, the hydroxyl group at C6 of the sugar moiety was acylated with acridine/acridone N-substituted omega-aminoalkanocarboxylic acids (Scheme 1), whereas the conjugates of type B (Table 2) and three analogues of type C or D (Scheme 2) have an amide bond formed between the carboxylic group of isoglutamine and the amine function of the respective acridine/acridone derivatives. The preliminary screening data indicate that the analogues of groups A, C, and D exhibit small cytotoxic activity, whereas several analogues of type B, 4b, 4c, 4e, 4g, 4h, 4i, and 4l, exhibiting potent in vitro cytotoxic activity against a panel of human cell lines (Table 4), have been selected by the National Cancer Institute (NCI) Evaluation Committee for further testing. Analogues 4b and 4h were active in the in vivo hollow fiber assay (Table 5). Analogue 3a shows an immunostimulating effect on the cytotoxic activity of the NK cells obtained from the spleen of healthy and Ab melanoma bearing animals.

Natural killer activity and thyroid hormone levels in young and elderly persons

BACKGROUND

On the basis that (1) multiple interactions exist between the hormonal and immune systems, and (2) aging is accompanied by changes in thyroid hormone metabolism and responsiveness, we postulate that thyroid hormones may be involved in the observed decrease in natural killer (NK) activity in a population of apparently healthy elderly subjects. The purpose of the study is to compare NK cytotoxic activity and serum concentrations of TSH and thyroid hormones in healthy old and young people, and to assess in vitro the effects of triiodothyronine (T(3)) on NK activity.

MATERIALS AND METHODS

Sixteen of the 47 healthy old people (mean age 64 +/- 5.2) were classified as optimally healthy, and the remainder as 'almost healthy' (according to the criteria of the Senieur protocol) [Ligthart et al., Mech Ageing Dev 1984;28:47-55]; the mean age of the healthy young people was 23.3 +/- 2.3 years. NK cytotoxic activity of peripheral blood mononuclear cells was assessed using (51)Cr release from K562 target cells. The cutoff level for defining low and high NK responses was set at a value of 20%. Serum concentrations of TSH, total thyroxine (T(4)) and total triiodothyronine (T(3)) were measured by radioimmunoassay.

RESULTS

NK activity in the 'optimally healthy' elderly was high (mean 41 +/- 12%, SE), whereas 'almost healthy' subjects showed low NK activity (mean 6 +/- 5%). Serum T(4) and TSH levels, but not T(3) concentrations were similar in both the young and old. We observed a significant correlation (r = 0.53, n = 21, p < 0.05) between the serum total T(3) level and the NK activity in the elderly individuals. Under in vitro conditions exogenous T(3) significantly increased NK activity in the elderly subjects who had serum T(3) values at the lower end of the reference range. However, no effect of T(3) on NK activity was observed in peripheral blood mononuclear cells obtained from either old or young individuals who had serum T(3) levels at the midpoint of the range.

CONCLUSION

Decreased serum concentrations of total T(3) may contribute to low NK activity in the 'almost healthy' subgroup of the elderly.

Luteal phase of the menstrual cycle in young healthy women is associated with decline in interleukin 2 levels

The aim of this study was to look at the possible changes in the blood levels of Interleukin 2 (IL2) during the sexual cycle in generally healthy, young, regularly menstruating women. The concentrations of progesterone and 17beta-estradiol were measured using radioimmunological assay. The bioactivity of interleukin 2 was measured using a biological test on the IL2-sensitive CTLL cell line. The percentage of lymphocytes with intracellular IL2 was determined by flow cytometry. Eighteen healthy volunteers (19-29 years old) were examined on days 5, 8, 14, 18 and 25 of the same cycle. All women were characterised by a regular menstrual cycle as per physiological levels of 17beta-es-tradiol and progesterone. The luteal phase of the cycle was characterised by both a decrease of IL2 blood levels and a decrease in the percentage of intracellular 1L2-containing lymphocytes stimulated in vitro. The IL2 level fluctuations observed during the menstrual cycle may be one factor causing pre-menstrual infections observed in young women. On the other hand, the decrease of IL2 may be seen as a start of the immune suppression necessary for an embryo's nidation.

The effects of fasting and refeeding on serum parathormone and calcitonin concentrations in young and old male rats

Although fasting and refeeding reveal the existence of age-related changes in carbohydrate and lipid metabolism, the effects of aging on mineral metabolism in refed animals are unknown. We therefore investigated hormonal regulation of calcium metabolism in young (4 months) and old (26 months) male rats fasted for 48 hours and then refed for 4 or 24 hours. Serum concentrations of total and ionized calcium and parathormone were similar in control young and old rats. Serum calcitonin level was higher, and the concentrations of albumin and inorganic phosphate and alkaline phosphatase activity were lower in fed old rats. In young fasted rats, the serum ionized and total calcium was decreased, and phosphate concentration was increased. In old rats, fasting resulted in the increase of serum parathormone level. Fasting reduced serum alkaline phosphatase activity to a similar extent in both age groups. In young rats, refeeding for 24h normalized serum calcium and phosphate levels and alkaline phosphatase activity, and decreased serum concentrations of PTH and calcitonin. In old refed rats, serum calcitonin concentration was raised by 77% compared to fed or fasted animals, whereas parathormone levels were normalized. Our results indicate that old fasted or refed rats maintain normal serum calcium concentration in a different way than young animals, possibly through the increase in serum levels of parathormone and/or calcitonin. Thus, dietary manipulations such as fasting and refeeding constitute an interesting model for the investigation of the effects of aging on the hormonal regulation of serum calcium level.

The effects of galactosamine on UTP levels in the livers of young, adult and old rats

Galactosamine (GalN), a well-known hepatotoxin that depletes the cellular pool of uracil nucleotides, was previously shown to have greater impact on the inhibition of protein synthesis in hepatocytes of old rats as compared with young animals (Kmieć 1994, Ann. N.Y. Ac. Sci. 717, 216-225). In the present study we compared the effects of GalN on the nucleotide content (measured by ion-exchange HPLC) in the livers of young (4 months), adult (12 months), and old (24-26 months old) rats two hours after its intraperitoneal administration. UTP content of the livers of old control rats was significantly lower (by 28%) than that of young animals. GalN administration decreased the UTP content in the livers of young, adult and old rats by, respectively, 55%, 65% and 89%, and increased the content of UDP-sugars by 189%, 175% and 305%. The hepatic content of ATP, ADP, AMP, NAD, GTP except CTP did not differ significantly among the age groups of rats studied, and was not changed by GalN treatment. The content of CTP was significantly higher in old rats (P < 0.03) upon GalN treatment. The lower hepatic content of UTP may partially explain the increased sensitivity of hepatocytes and livers of old rats to the action of galactosamine, and possibly to other hepatotoxic compounds that decrease transcription in the liver.

Compensatory effect of TNFalpha on low natural killer activity in the elderly

Regulatory effect of CD25, an activation antigen the alpha subunit of interleukin 2 receptor (IL2R) on the activity of natural killer (NK) cells was studied in fifty elderly (57-70 years old) and fifty young people (19-35 years old). Cytotoxic NK activity was assessed by 51Cr release assay, the levels of interleukin 2 (IL2) and tumour necrosis factors alpha (TNFalpha) were measured using bioassays and expression of CD16 and CD25 proteins by flow cytometry. Low NK activity in the elderly was associated with decline of full health, lowered serum concentration of IL2 and increased production of TNFalpha during NK reaction. Inhibition of TNFalpha activity by anti-TNF monoclonal antibody suppressed exclusively NK activity of low NK responders. Moreover, stimulation in vitro of blood mononuclear cells, with TNFalpha induced in the elderly low NK responders a significantly higher increase of the CD25 expression on the surface of NK cells as compared with that in the elderly high responders. Since the CD25 molecule constitutes a subunit of the high affinity receptor, binding IL2 to immunocompetent cells, its increased expression on NK cells of low NK responders would enable them to bind even low amounts of the endogenous IL2 available in this group of the elderly. Thus, an overproduction of TNFalpha seems to be a mechanism compensating, in the non-fully healthy elderly, for the decreased IL2 production, promoting efficient cytotoxic reaction.

Synergistic effect of the angiogenesis inhibitor TNP-470 and tumor necrosis factor (TNF) on Bomirski Ab melanoma in hamsters

Bomirski Ab transplantable melanoma bearing hamsters were treated with angiogenesis inhibitor TNP-470 or with rat tumor necrosis factor (TNF) at doses of 20 micrograms and 40 micrograms or with both TNP-470 and TNF at a dose of 20 micrograms each. The size of the growing tumor was measured everyday from the day when it was palpable. After the death of the animals the final size of their tumors was measured and the number and localisation of metastasis were determined. It was found that the rate of tumor growth was lowest in the group of animals treated with TNF at a dose of 40 micrograms and in the group of animals treated with TNP-470 and TNF at a dose of 20 micrograms. The frequency of metastasis was different in the experimental groups although their location was similar. The longest living animals belonged to the group treated with both TNP-470 and TNF. The results of the investigation indicate that TNP-470 and TNF act in a synergistic way that allows a decrease in the effective dose of TNF thus diminishing its noxious side effects.

Lower interleukin-2 and higher serum tumor necrosis factor-a levels are associated with perimenstrual, recurrent, facial Herpes simplex infection in young women

The aim of this study was to look at a possible relationship between the recurrent perimenstrual dermatosis - facial Herpes simplex infection and the serum concentrations of interleukin-2 (IL-2) and tumor necrosis factor alpha (TNF-alpha). Twenty-one volunteers (19-26 year olds) were examined at five points of the menstrual cycle. Ten volunteers were characterised by recurrent Herpes simplex infection lasting either from the 18th or the 25th day of the menstrual cycle until a few days after menstruation. Eleven young women without symptoms formed the control group. Both groups were similar as regards blood levels of 17beta-estradiol and progesterone. The group with the frequent infectious symptoms was characterised, however, by lower concentrations of IL-2 throughout the whole menstrual cycle, as compared to those without the symptoms. Levels of IL-2 in this group additionally dropped significantly on the 18th and on 25th day of the cycle. Moreover, the group with symptoms was characterised by higher level of TNF-alpha on the 18th day. These changes were found during the menstrual cycle of the women with recurrent herpes infection who however, at the time of the examination were free of the clinical symptoms. There was a similar tendency in both groups towards an increase in the levels of TNF-a around menstruation. Measurement of the other serum pro-inflammatory marker - IL-6 showed higher levels of this cytokine during the menstrual cycle in the group with the clinical symptoms. The results indicate that a decrease of IL-2 together with an increase of TNF-alpha and IL-6 in the serum seem to be related to recurrent perimenstrual Herpes simplex infection.

Compensatory effect of TNFalpha on low natural killer activity in the elderly

Regulatory effect of CD25, an activation antigen the alpha subunit of interleukin 2 receptor (IL2R) on the activity of natural killer (NK) cells was studied in fifty elderly (57-70 years old) and fifty young people (19-35 years old). Cytotoxic NK activity was assessed by 51Cr release assay, the levels of interleukin 2 (IL2) and tumour necrosis factors alpha (TNFalpha) were measured using bioassays and expression of CD16 and CD25 proteins by flow cytometry. Low NK activity in the elderly was associated with decline of full health, lowered serum concentration of IL2 and increased production of TNFalpha during NK reaction. Inhibition of TNFalpha activity by anti-TNF monoclonal antibody suppressed exclusively NK activity of low NK responders. Moreover, stimulation in vitro of blood mononuclear cells, with TNFalpha induced in the elderly low NK responders a significantly higher increase of the CD25 expression on the surface of NK cells as compared with that in the elderly high responders. Since the CD25 molecule constitutes a subunit of the high affinity receptor, binding IL2 to immunocompetent cells, its increased expression on NK cells of low NK responders would enable them to bind even low amounts of the endogenous IL2 available in this group of the elderly. Thus, an overproduction of TNFalpha seems to be a mechanism compensating, in the non-fully healthy elderly, for the decreased IL2 production, promoting efficient cytotoxic reaction.

The effects of galactosamine on UTP levels in the livers of young, adult and old rats

Galactosamine (GalN), a well-known hepatotoxin that depletes the cellular pool of uracil nucleotides, was previously shown to have greater impact on the inhibition of protein synthesis in hepatocytes of old rats as compared with young animals (Kmieć 1994, Ann. N.Y. Ac. Sci. 717, 216-225). In the present study we compared the effects of GalN on the nucleotide content (measured by ion-exchange HPLC) in the livers of young (4 months), adult (12 months), and old (24-26 months old) rats two hours after its intraperitoneal administration. UTP content of the livers of old control rats was significantly lower (by 28%) than that of young animals. GalN administration decreased the UTP content in the livers of young, adult and old rats by, respectively, 55%, 65% and 89%, and increased the content of UDP-sugars by 189%, 175% and 305%. The hepatic content of ATP, ADP, AMP, NAD, GTP except CTP did not differ significantly among the age groups of rats studied, and was not changed by GalN treatment. The content of CTP was significantly higher in old rats (P < 0.03) upon GalN treatment. The lower hepatic content of UTP may partially explain the increased sensitivity of hepatocytes and livers of old rats to the action of galactosamine, and possibly to other hepatotoxic compounds that decrease transcription in the liver.

Nitric oxide, heparin and procaine treatment in experimental ceruleine-induced acute pancreatitis in rats

The aim of the study was to investigate the impact of L-arginine (nitric oxide donor), L-NNA (NO synthase inhibitor), heparin and procaine on the pancreas' microcirculation, serum interleukin 6 (IL-6) level, and microscopic alterations of the pancreatic gland in acute pancreatitis (AP) in rats. AP was induced by 4 i.p. injections of cerulein (15 micrograms/kg/h). Microcirculatory values of the pancreas were measured by means of laser Doppler flowmetry 5 h after the first cerulein injection. Remarkable morphologic changes in the pancreas, including parenchymal necrosis, an elevation of serum IL-6 activity, and significant drop of pancreatic capillary perfusion was observed in rats with NO synthase inhibition. L-arginine improved the pancreatic microcirculation but worsened the microscopic alterations within the pancreas. Heparin had a beneficial effect on the microcirculatory values, serum IL-6 activity, and morphologic changes. Procaine had no effect on the course of AP. Authors conclude that heparin, improving the pancreatic capillary blood perfusion, may be considered as a promising therapeutic agent in acute pancreatitis.

Recombinant human erythropoietin stimulates production of interleukin 2 by whole blood cell cultures of hemodialysis patients

The impairment of function of human T lymphocytes, leading to an inappropriate cytokine production, is partially responsible for defective immunological response in hemodialysis patients (HD). Recent data suggest that recombinant human erythropoietin (rhEPO) may exert immunological effects. The aim of this study was to find out whether rhEPO treatment of the HD patients may have an effect on the interleukin 2 (IL-2) production by their whole blood cell cultures. The study was carried out in 10 HD patients receiving rhEPO for 6 months. Compared with the levels seen before the treatment, the concentration of IL-2 increased in the phytohemagglutinin-stimulated whole blood cell cultures of 7 of 10 patients under study. Addition of rhEPO in vitro to the whole blood cell cultures of the HD patients before implementation of erythropoietin confirmed that rhEPO is able to directly stimulate IL-2 production. Our studies show that the therapy with rhEPO affects IL-2 secretion.

The upregulation of TNF alpha production is not a generalised phenomenon in the elderly between their sixth and seventh decades of life

The aim of this paper was to analyse the link between the intensity of tumor necrosis factor alpha (TNF alpha) production and the health status of the elderly and to find out whether the age between sixty and seventy is a 'turning point' for the changes in the production of this cytokine. Fifty elderly volunteers (age range: 60-70), twenty-five middle-aged (age range: 36-59) and fifty young (age range: 20-35) were enrolled into the study. Their health status was graded as 'healthy' and 'almost-healthy'. The level of TNF alpha was determined by bioassay, the activity of the TNF alpha gene was analysed in non-stimulated PBMC by the RT-PCR method. The results showed that the production of TNF alpha in the 'healthy' elderly people is not upregulated until the age of sixty-seventy. The 'almost-healthy' elderly are characterised by a higher release of TNF alpha from the cultures of non- and stimulated PBMC and an activation of the TNF alpha gene in the non-stimulated PBMC. Summarising, our results indicate that the deterioration of health status is a prerequisite for an exaggerated TNF alpha production by peripheral blood mononuclear cells of people between the sixth and seventh decades of life.

The influence of recombinant human erythropoietin on tumor necrosis factor alpha and interleukin-10 production by whole blood cell cultures in hemodialysis patients

Impaired immunological response in hemodialysis (HD) patients, which leads to inappropriate cytokine production, is partially caused by the hyperstimulation of both T lymphocytes and monocytes/macrophages. Recent data suggest that human recombinant erythropoietin (rhEPO) may have an immunological action. The goal of our study was to estimate the influence of rhEPO treatment on the production of the inflammatory cytokine tumor necrosis factor alpha (TNFalpha) and antiinflammatory cytokin interleukin-10 (IL-10) in 10 HD patients receiving rhEPO for 6 months. The levels of cytokines were measured in the in vitro cultures of whole blood. The level of IL-10 increased in all treated patients during the therapy, and it was accompanied by a transitory decrease of TNFalpha. The results of our studies suggest that rhEPO may reduce the inflammatory process by decreasing production of TNFalpha and increasing production of IL-10.

Significance of tumor necrosis factor alpha in patients with long-standing type-I diabetes mellitus

Fifteen out of the forty-five patients with long-standing diabetes mellitus type I were characterised by the presence of TNFalpha in the sera when examined on several occasions over a period of five years. TNFalpha-producing patients had a better control of the disease and a smaller percentage of them suffered from diabetic complications as compared with those not producing this cytokine. TNFalpha-producing patients had lower levels of the proinflammatory markers - IL6 and CRP, and higher concentrations of ACTH and cortisol than those not producing this cytokine. We suggest that TNFalpha released systemically in diabetic patients stimulates the hypophysis-adrenal axis, and in that way indirectly ameliorates autoimmune response occurring during the advanced phase of the disease.

Increase of interleukin 6 and decrease of interleukin 2 production during the ageing process are influenced by the health status

The ageing process is accompanied by the disregulation of interleukin 2 (IL2) and interleukin 6 (IL6) production. In our paper, we asked whether the age between 60 and 70 years is a turning point for the disregulation of both IL2 and IL6 production. Fifty volunteers 60-70 years old, 25 aged 36-59, and 50 of 20-35 years old were enrolled into the study. Their health status was graded according to the criteria of the Senieur Protocol (SP) as 'healthy' and 'almost-healthy'. The cytokines level was determined in the sera of the volunteers. Moreover, the spontaneous release of IL6 by peripheral blood mononuclear cells (PBMC) and the activity of the IL6 gene in non-stimulated PBMC were also analysed. Cytokine levels were measured by biological assays, mRNA for IL6 was detected by RT-PCR method. The results showed that the production of IL2 is not disregulated in the 'healthy' people until the age of 60-70. People not fulfilling all SP criteria are characterised by a lower level of IL2 in the sera. The overproduction of IL6 into the sera and supernatants from non-stimulated PBMC and PBL as well as the activation of IL6 gene start between the ages 36 and 59 and is more pronounced in the 'almost-healthy'.

Suppression of growth of Bomirski Ab melanoma and its metastasis in hamsters by angiogenesis inhibitor TNP-470

The growth of solid tumors and their metastasis is dependent on the development of new blood vessels (angiogenesis). In this study, we examined the effect of the angiogenesis inhibitor TNP-470 on a fast growing melanoma in hamsters. The effect was observed both on tumor growth and metastasis. Treatment with TNP-470 caused a significant decrease in the rate of tumor growth and suppression of the development of metastasis in 63% of treated animals. Some of the hamsters treated with TNP-470 had the tumor excised and the effect of that operation on the development of metastasis was examined. In such cases the inhibitory effect of TNP-470 was weaker than in tumor bearing animals. This indicates that excision of tumor created more favourable conditions for angiogenesis and that the dose of TNP-470 should be increased to be effective in such conditions.

Overactivity of tumor necrosis factor-alpha but not interleukin 6 is associated with low natural killer cytotoxic activity in the elderly

In this paper we asked whether the increased production of two proinflammatory cytokines-tumor necrosis factor-alpha (TNF alpha) and interleukin-6 (IL6) in the absence of the inflammatory stimulus, a phenomenon frequently occurring in the elderly, may contribute to the decrease of natural killer (NK) cytotoxic activity. NK cell activity is a part of a nonspecific immunity directed against infected and transformed cells. We measured the levels of bioactive TNF alpha and IL6 during cytotoxic NK reactions and analyzed the effect of neutralizing monoclonal antibodies anti-TNF alpha and anti-IL6 on the outcome of cytotoxic reaction. Bioactive TNF alpha was produced in higher amounts during cytotoxic reactions of the elderly with low NK activity in comparison with its production by the elderly with high NK activity. Anti-TNF alpha decreased already low cytotoxic responses of the elderly while not having an effect on the cytotoxic potential of high responders. More of the bioactive IL6 was released during cytotoxic reactions of the elderly as compared with young people. There was, however, no relation between the height of NK cytotoxic activity and the amount of IL6. Our results suggest that the increased level of TNF alpha seen in the elderly low NK responders may pose a compensatory mechanism, necessary to keep the highest possible level of NK responses. The increased bioactivity of IL6 during NK reaction of the elderly does not seem to participate in the regulation of the level of NK cytotoxic activity.

Elderly high NK responders are characterized by intensive proliferative response to PHA and Con A and optimal health status

In this paper we verify a hypothesis emerging from recent immunogerontological studies assuming that an elevated level of NK activity in the elderly may be regarded as a factor compensating for a decreased reactivity of T cells. According to this assumption a high NK activity should be associated with a poor reactivity of T cells. In our study the mitogenic responses of lymphocytes of the elderly and the young high and low NK responders to phytohemagglutinin (PHA) and Concanavalin A (Con A) were measured. A high level of NK activity was not found, as would be expected from the hypothesis, to be associated with a poor reactivity to PHA and Con A. In contrast, the mitogenic response to PHA and Con A was intensive in both the young and old high NK responders while weak proliferative responses to T cell mitogens were characteristic of the young and old low NK responders. Thus, our results do not support the assumption of an association between a high NK activity and a low proliferative response to T cell mitogens in the elderly. We also found that both the elderly and the young high NK responders were characterized by an optimal health status.

Monocytes are responsible for depressed natural killer (NK) activity in both young and elderly low NK responders

Two age groups--young (19-35) and elderly (70-91)--were compared with respect to natural killer (NK) cytotoxic activity. In both groups, low and high NK responders could be distinguished. Low NK responders constituted about 70% of all elderly and 40% of young individuals. The differences in the magnitude of NK activity among the young and elderly groups could only be observed when peripheral-blood mononuclear cells but not peripheral-blood lymphocytes were used as effector cells in a 51Cr release assay. Experiments with removal or addition of graded numbers of monocytes showed that these cells were responsible for the low level of NK activity in both the young and elderly low NK responders.

Natural killer sensitivity of tumor cells isolated from primary and metastatic lesions of four Bomirski melanoma variants

Natural killer (NK) sensitivity of melanoma cells isolated from primary and metastatic lesions of four Bomirski melanoma variants was compared. The hamster melanomas differed in their growth rate and metastatic pattern. We found that during tumor growth of all the variants tested, NK sensitivity of melanoma cells at the metastasis formation stage was significantly lower in both primary and metastatic tumors than in cells isolated from primary tumors at transplantation. In the case of Ma, Ab and Ab-455, NK sensitivity of primary tumor cells was higher than that of the cells isolated from metastatic deposits. These data obtained from a spontaneous metastasis tumor model argue for the role of NK cells in preventing metastatic spread of Bomirski melanomas studied.

Modification of mitogenic response to concanavalin A of lymphocytes from old-aged donors by ion channel blockers

Mitogenic response of lymphocytes from young and old donors to Concanavalin A in the absence or presence of Na+ channel blocker--saxitoxin--was compared. Effect of Ca++ channel blockers (Verapamil Diltiazem) on mitogenic response of lymphocytes from old subjects was also examined. It was found that the mitogenic response to Concanavalin A of lymphocytes from donors was significantly lower than that of young ones. In the presence of Saxitoxin the enhancement of the response was noticeable in both groups and the mean responses were similar. However, among the old donors, opposite to the young ones, very high and very poor responders were present. Verapamil and Diltiazem caused significant reduction of mitogenic response to Concanavalin A in the group of old donors. These observations suggest a possible effect of ion channel blockers on immunological functions which would have special significance for old organisms.

Activity of acid phosphatase in target binding cells expressing NK cytotoxic potential

Activity of acid phosphatase was analysed in the NK-effectors from human blood forming conjugates with K 562 cells. Presence of activity of acid phosphatase was associated with the cytolytic potential of the NK-effectors. The non-lytic target-binders did not express activity of this enzyme. The results suggest that activity of acid phosphatase in the effector cells of NK reaction is important in the lethal hit stage.

Effects of air ions on the membrane Na, K-ATPase activity of L 1210 cells

The effect of exposure of L 1210 mouse leukemia cells to artificially generated air ions on the activity of membrane Na, K-ATPase in the cells was investigated. The exposure of cells to air ions of both signs gave identical results, i.e. diminution of transport activity of the enzyme, measured by radioactive 86Rb transport into the cell (ouabain-dependent). Passive ouabain-independent transport of Rb+ into the cells remained unchanged in the air ion-treated cells, as did the passive efflux of the radioisotope from preloaded cells. The possible explanation of the phenomena observed is discussed.

Effect of air ions on L 1210 cells: changes in fluorescence of membrane-bound 1,8-aniline-naphthalene-sulfonate (ANS) after in vitro exposure of cells to air ions

The ability of air ions to produce changes in the electrical properties of L 1210 mouse leukemia cells was tested. The fluorescence of ANS incorporated into a membrane lipid bilayer (measured microphotometrically) was used as a probe. It was shown that the action of air ions of both signs could change (negative ions by increasing and the positive ones by decreasing) the fluorescence intensity of ANS in the cell surface structures or to an imbalance of ions inside and outside the cell. Both possibilities are discussed in the light of the results of experiments using ouabain or biguanide as factors diminishing the intensity of ANS fluorescence.

Effect of air ions on healing of wounds of rat skin

Rat skin was deprived of epidermis and the wound was exposed to ions generated with Bion 80 apparatus, for 3 h, just after wounding, only once. In comparison with the control, positive air ions retarded and negative air ions accelerated the wound healing. This effect was almost the same when air, nitrogen, oxygen and carbon dioxide were applied. A direct action of air ions is suggested.

Age-dependent decline of natural killer and antibody-dependent cell mediated cytotoxicity activity of human lymphocytes is connected with decrease of their acid phosphatase activity

Decline of cytotoxic potential of lymphocytes of aged persons in ADCC and NK cell mediated cytotoxic reaction was paralleled by a drop in the activity of acid phosphatase. Intensity of ADCC reaction and the level of acid phosphatase activity showed statistically significant correlation when these two parameters were measured in peripheral blood of the same persons. The role of acid phosphatase in cytotoxic function of lymphocytes is discussed.

Activity of acid phosphatase in resting and mitogen-stimulated human peripheral blood lymphocytes

Activity of acid phosphatase was found to be higher in T than in non-T cells of human peripheral blood lymphocytes. The T cell mitogen PHA induced an increase in the magnitude of acid phosphatase activity, while the B cell mitogen LPS was not able to produce any effect on acid phosphatase activity. Acid phosphatase activity in lymphocytes correlated with their spontaneous proliferative activity.

Increase of size and dry mass of mouse erythrocytes depending on age of donors

It was found that during aging of mice the size and the dry mass of their erythrocytes increased. Similarity of this phenomenon to that observed during aging in vitro and in vivo is suggested.

Age-related changes of activity of acid phosphatase in PHA-stimulated lymphocytes

Peripheral blood lymphocytes of 70-year-old individuals as well as spleen cells of 18-month-old Balb/c mice were characterized by diminished activity of acid phosphatase in relation to the activity of that enzyme in cells from young subjects. Simultaneously performed histochemical tests revealed that aging process in both species examined was accompanied by a reduction of the number of cells, disclosing the activity of acid phosphatase. Age-related differences with regard to the level of acid phosphatase became more pronounced after stimulation of cells with PHA. The decrease of acid phosphatase activity during aging is discussed in relation to the function of lymphocytes.

Urea synthesis in hepatocytes isolated from young and old rats

Effects of glucagon and epinephrine stimulation on urea synthesis from lactate, pyruvate, NH4Cl, and ornithine in isolated rat hepatocytes from young and old rats were compared. It was found that the production of urea from those substrates was almost the same in both age groups. The concentrations of hormones that caused the maximum effect were the same for both groups of rats. The effectiveness of the stimulation of urea synthesis by glucagon and epinephrine was the same in hepatocytes isolated from young and old rats.

Dielectric properties of murine lymphocytes

Dielectric measurements in frequency range from 0.032 up to 110 MHZ were performed on the suspension of lymphocytes isolated from the spleen of Balb/c mouse. Basing on measurements of electric capacitance (C) and electric conductance (G) of lymphocyte suspension and on the simplified Pauly-Schwan equations the following electrical parameters of lymphocytes were calculated: relative electrical permittivity of the intracellular substance (epsilon i = 136) electrical conductivity of the inner phase (intracellular substance) (kappa i = 8.94 mS/cm), specific capacitance of cell membrane (CM = 0.82 microF/cm2). Relative electrical permittivity of the membrane (epsilon s = 4.6) has also been calculated. Two of those quantities (epsilon i = and kappa i) additionally determined by means of empirical dependences. The value of epsilon i and kappa i were respectively 125 and 8.79 mS/cm. All those measurements were taken at temperature amounting to 293 K.

Age-dependent changes of hormone-stimulated gluconeogenesis in isolated rat hepatocytes

Effects of glucagon or catecholamine stimulation on glucose synthesis from lactate/pyruvate, alanine, fructose or glycerol in isolated hepatocytes from young and old rats were compared. It was found that production of glucose by non-stimulated hepatocytes was almost the same in hepatocytes both from young and old rats. The concentrations of hormones which caused the maximal effect were the same for both compared groups of rats. However, the effect of stimulation by glucagon was significantly greater in hepatocytes of young rats than of old ones, when lactate/pyruvate or alanine were used as substrates, while no such difference was observed when fructose or glycerol were used. Epinephrine and norepinephrine stimulated glucose synthesis from all substrates investigated to the same extent in hepatocytes isolated from both compared groups of rats. The biochemical and physiological aspects of these findings are discussed.

The ANAE reaction pattern of reticular stromal cells of lymphatic organs from normal and hydrocortisone--treated mice

The pattern of alpha-naphthyl-acetate esterase (ANAE) activity in stromal and lymphatic cells has been examined in lymphatic organs from normal and hydrocortisone (HC)-treated mice. The distribution of ANAE-positive lymphocytes as well as stromal cells in peripheral lymphatic organs was different in T- and B-dependent regions, while in the thymus there was the difference between cortex and medulla. The HC application evoked a marked changes in the pattern of ANAE-positive cells distribution of the thymus, producing only a slight ones in the remaining organs. The influence of HC on the ANAE reaction intensity and distribution in the examined tissue sections is discussed.