Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously shown that the synthetic peptide pGlu-Glu-Asp-Cys-Lys (pEEDCK monomer) inhibits the cytostatic drug-induced proliferation of hematopoietic stem cells CFU-S. Keeping CFU-S quiescent by pEEDCK treatment renders them insensitive to cycle-specific cytostatic drugs and leads to reduced toxicity. Here we show that pEEDCK application during repeated (twice) administration of clinically relevant (nonlethal) 1-beta-D-arabinofuranosylcytosine (Ara-C) doses reduced the percentage of CFU-S in S-phase from 60%-70% to 25%-30% and led to a sustained stem cell number in the bone marrow (BM), whereas unprotected mice had lost about 75% of their CFU-S population. Owing to its cysteine content, the pEEDCK monomer is easily oxidized. The resulting dimer (pEEDCK)2 is a potent stimulator of hematopoiesis. As we show, it can be used for postchemotherapy acceleration of hematologic recovery, similar to the use of recombinant hematopoietic growth factors. A single injection of 30 micrograms/kg pEEDCK monomer to mice 2 hours before the second Ara-C injection retarded onset of neutropenia (by 2 to 3 days) and improved recovery after depression. The quantitative degree of neutropenia was not changed. Postchemotherapy (Ara-C administered twice, followed by N-mustard) infusion of the stimulatory (pEEDCK)2 dimer (1.4 micrograms/kg/d) produced a 4.6-fold increase of progenitor levels (6.7 CFU-GM/1,000 BM cells v 1.45 CFU-GM/1,000 in normal mice) 2 days after the end of the cytostatic treatment when CFU-GM were not detectable in unprotected mice. This increase was followed after several days by strongly elevated granulocyte counts, which remained high for approximately 1 week. Up to 75% of the peripheral leukocytes were mature polymorphonuclear leukocytes (PMN) during this phase. Ara-C (twice) and monomer treatment as above followed by dimer infusion resulted in the complete protection of hematopoiesis. Mice treated with the protective pEEDCK monomer plus stimulatory dimer did not develop the leukocyte depression noted in unprotected animals. The inhibitory monomer appears to keep the stem cell population numerically and qualitatively intact, thus providing optimum target cell conditions for the subsequent stimulator (dimer) treatment. Our results show that the hemoregulatory peptide monomer and dimer can be used for improving the hematologic status of mice treated with clinically relevant doses of cytostatic drugs (antimetabolite and alkylating, alone and in combination). Combining both peptides can prevent occurrence of neutropenia completely. Both peptides can be obtained easily by chemical synthesis and are also active on human cells. They are thus highly promising candidates for application as multilevel hemoprotectors in cancer chemotherapy.
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PMID:Protection from arabinofuranosylcytosine and n-mustard-induced myelotoxicity using hemoregulatory peptide pGlu-Glu-Asp-Cys-Lys monomer and dimer. 200 54

We have previously shown that the stem cell inhibitory peptide pGlu-Glu-Asp-Cys-Lys (pEEDCK monomer) leads to a good tolerance of otherwise lethal multiple ara-C doses and an increased survival of ara-C + peptide treated mice. This effect was due to the prevention of drug-induced CFU-S proliferation, thus keeping stem cells in a quiescent state insensitive to ara-C. Here we show that the pEEDCK monomer also inhibits stem cell proliferation after clinically relevant (non-lethal) ara-C doses. This leads to a sustained (100%) stem cell number in the femoral bone marrow, which was greatly reduced without protective peptide treatment (27%). We have measured the kinetics of influx of CFU-S into the empty S-phase (after two consecutive ara-C injections). This influx reached peak levels of 60-70%; pEEDCK treatment reduced it to 25-30%. Due to its cysteine content the pEEDCK monomer is easily oxidized and forms a symmetric disulfide-bonded dimer (pEEDCK)2. This dimer is a potent stimulator of haemopoiesis. Various modes of protective peptide treatment (monomer and dimer) were investigated in conjunction with a standardized protocol of 2 x 300 mg/kg ara-C given 12 h apart. (a) ara-monomer-ara: The administration of pEEDCK-monomer 2 h before the second ara-C injection retarded the onset of neutropenia, shortened its duration and improved recovery after depression. The degree of short-term neutropenia was not changed. (b) ara-ara-HN2-dimer: Post chemotherapy infusion of the stimulatory (pEEDCK)2 dimer led to considerable increases of progenitor levels (6.8 CFU-GM/1000 bone marrow cells vs. 1.2 CFU-GM/1000 in normal mice) 2 days after cytostatic treatment when CFU-GM were not detectable in unprotected mice. This increase was followed by greatly elevated granulocyte counts (8000 PMN/mm3 vs. 750 PMN/mm3 in normal mice). In the dimer-treated mice, up to 75% of the peripheral leukocytes were mature PMN (normal, 10%). (c) ara-monomer-ara-dimer: ara-C and monomer treatment as above (a) followed by dimer infusion led to complete protection of haemopoiesis. Mice treated with the protective pEEDCK monomer plus stimulatory dimer did not develop the leukocyte depression seen in unprotected animals. Our results show that the haemoregulatory peptide monomer and dimer can be used to improve the haematological status of mice treated with clinically relevant doses of cytostatic drugs (anti-metabolite and alkylating, alone and in combination). The pEEDCK monomer and dimer are equally active also on human haemopoietic cells.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The use of haemoregulatory peptides (pEEDCK monomer and dimer) for reduction of cytostatic drug induced haemopoietic damage. 227 50

According to the literature, Cyclosporine A (CsA) is said to suppress specifically the activity of T and B cells. A significant influence on phagocyte function has been neglected. However, aggravated courses of bacterial and fungal infections have been frequently reported under the treatment with CsA, suggesting that a latent depression of phagocytic activity may possibly occur under clinical circumstances. Therefore, this study set out to assess whether CsA can also change granulocyte function under therapy conditions or not. Thirty-seven patients, 3 months-10 years after kidney transplantation being under immunosuppressive treatment with CsA + Prednisolone (n = 25), Azathioprine + Prednisolone (n = 6) and under Prednisolone alone (n = 6) underwent the study. 18 healthy persons served as a normal control group. Granulocyte function was tested ex vivo by chemiluminescence (CL) after stimulation with phorbolmyristate acetate (PMA) and with zymosan (zym) activated autologous or pool-serum. The obtained data were correlated to corresponding serum or plasma levels of CsA, human leukocyte elastase (HLE) and neopterin. Comparing the three therapy groups with the healthy control and with each other no differences could be seen in median CL values; but there was a significant (p = 0.05) negative correlation between CsA blood levels and maximum CL values of PMN. Such inhibition of CL could be calculated for zym but not for PMA stimulated PMN; suggesting that the CsA mediated inhibition of granulocyte function may be only partial and restricted to phagocytosis. In addition, a positive correlation between serum levels of human leukocyte elastase (HLE) and neopterin could be found. This indicates a simultaneous influence of CsA on both PMN and macrophages.
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PMID:Latent inhibition of granulocyte function by cyclosporine A. 227 42

Both pentamidine isethionate and pentamidine mesylate induced a depression in activity of the NADPH-dependent oxidase system of stimulated human neutrophilic granulocytes. This drug-induced effect occurred at concentrations of 0.7, 1.1 and 1.5 mg/l, values within the therapeutic range after parenteral administration of a standard dose of either pentamidine salt, and was dose-related. There was no significant difference between the two salts with regard to this suppression in neutrophilic granulocyte function. The reduced activity of the NADPH-dependent oxidase system, after incubation with pentamidine salts, may be associated with the previously observed depression in candidacidal capacity of human neutrophilic granulocytes treated with these drugs.
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PMID:The effect of pentamidine salts on the NADPH-dependent oxidase of stimulated neutrophilic granulocytes. 232 2

The effect of recombinant human granulocyte colony-stimulating factor (G-CSF) on hematologic parameters was evaluated in a phase I clinical study in 18 patients with advanced malignancy. G-CSF was administered once daily as a 30-minute infusion for 14 days; three patients each were treated at increasing dose levels of 1, 3, 10, 30, and 60 micrograms kg-1 day-1. A transient decrease in neutrophil and monocyte counts was observed immediately after the G-CSF infusion, followed by a dose-dependent increase of up to 15-fold. G-CSF-induced neutrophils exhibited an increased O2- radical production, and serum levels of enzymes related to granulocyte turnover, including lysozyme and elastase, were markedly elevated during therapy. A dose-dependent depression of platelet counts occurred in the second third of the treatment course, followed by a spontaneous recovery despite continuing therapy. G-CSF was well-tolerated; minor to moderate bone pain was the most common side effect. The primary course of the malignant diseases studied was not significantly altered. G-CSF appears to be an appropriate means to selectively increase the number of functionally competent polymorphonuclear phagocytes.
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PMID:Hematologic effects of recombinant human granulocyte colony-stimulating factor in patients with malignancy. 247 25

Reports suggest that white blood cells are involved in the development of tissue ischaemia. No studies on leucocyte rheology in the earliest stages of ischaemia exist. In 10 peripheral vascular disease (PVD) patients, 10 stable angina pectoris (SAP) patients and two groups of 10 matched controls leucocytes were separated by density and adherence into their granulocyte, lymphocyte and monocyte subpopulations. Blood samples were taken from the PVD group and respective controls before and after treadmill exercise (5 min 2 km-1 h-1, 12% slope) and from the SAP patients and controls before and after cycle ergometer test (25 W every 3 min). All the subpopulations were filtered through five micron diameter pore filters. Compared to controls, calf pain in the PVD patients was associated with an increase in monocyte filterability (P less than 0.01). ST depression in the SAP patients was linked to impaired granulocyte filterability (P less than 0.04). Therefore leucocyte rheology appears impaired in the earliest stages of ischaemia.
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PMID:Human leucocyte rheology and tissue ischaemia. 250 15

The effect of 15 day programmed neurotization on the functional activity of the peritoneal macrophages has been studied. The NBT-test and the adhesion measurements were used. The experimental neurosis resulted in the decrease of the macrophage functional activity and in leukopenia. Tuftsin did not restore the stress induced depression of macrophage activity but led to additional rise of the adrenal glands weight and to pronounced granulocyte-monocytosis. Pentapeptide analog of tuftsin gave the additional inhibition of NBT-activity of the macrophage. Heptapeptide analog favoured the restoration of the macrophage activity after neurotization and stimulated lymphopoiesis.
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PMID:[Post-stress correlation of the functional activity of macrophages by tuftsin and its derivatives]. 255 46

Therapeutic concentrations (0.3-1.5 mg/l) of pentamidine isethionate and pentamidine mesylate, obtained after parenteral administration of either drug, did not affect oxygen consumption in the stimulated neutrophilic granulocyte. At concentrations of 0.7, 1.1 and 1.5 mg/l, superoxide production, hydrogen peroxide production, myeloperoxidase (MPO)-mediated iodination and hexose monophosphate shunt activity were suppressed relative to untreated cells (P less than 0.001 in each case). The depression in each activity was dose-related. There was no significant difference between the drugs with regard to these impairments in neutrophilic granulocyte function. This lowered respiratory burst activity, which would lead to a depression of MPO-dependent and MPO-independent processes in stimulated neutrophilic granulocytes, may be due to drug induced dysfunction of NADPH-oxidase.
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PMID:The effect of pentamidine salts on the respiratory burst of human neutrophilic granulocytes. 255 55

A phase I/II study of granulocyte colony stimulating factor (G-CSF) was undertaken in patients with advanced malignancy receiving melphalan to determine the granulocyte response, side-effects, and pharmacokinetics. Patients received doses of 1-60 micrograms/kg intravenously. There were 3 patients at each dose level. Before chemotherapy the immediate effect of G-CSF was a transient depression in circulating neutrophils followed by a dose-dependent rise. Neutrophil counts up to 80 X 10(9)/l were achieved. G-CSF administration following melphalan reduced the period of neutropenia caused by melphalan. G-CSF was well tolerated and the only clinical observation that appeared related to G-CSF administration was slight bone pain during some infusions. G-CSF was rapidly cleared from the blood with a mean half-life of 110 min for the second phase. Reductions in the number of days of neutropenia following cytotoxic chemotherapy may reduce the morbidity and mortality of chemotherapy.
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PMID:Effect of granulocyte colony stimulating factor on neutropenia induced by cytotoxic chemotherapy. 289 12

Ochratoxin A (OCT A) has the potential to cause myelotoxicity in addition to the well-known toxic effects on the liver and kidney. Whereas in previous studies the bone marrow parameters were examined shortly after injection, experiments reported here were designed to determine whether mice would recover from the myelotoxic effects induced to OCT A injection and secondly whether mice previously injected to OCT A would be more sensitive to radiation-induced myelotoxicity than vehicle controls. Six-week old female B6C3F1 mice were injected intraperitoneally on alternate days over a week with a total dose of 20 or 40 mg/kg of OCT A and bone marrow parameters monitored for up to 16 weeks. Controls received vehicle alone. There was a suppression of marrow granulocyte macrophage progenitors (CFU-C) in OCT A-treated animals which returned to normal values by 2 weeks (20 mg/kg group) or by 5 weeks (40 mg/kg group) following the last treatment. Some of the OCT A-treated mice were additionally irradiated with 200 rads of whole body irradiation (WBI) at 10 and 52 days following OCT A injections. Irradiation caused a significant reduction in CFU-Cs in all mice but the effects were more pronounced in the mice that had received OCT A previously. The bone marrow parameters of 40 mg/kg OCT A-treated mice returned to normal by 6 weeks after first WBI. A second WBI produced similar depression in CFU-Cs with again a delayed 8 weeks recovery as compared to controls in both dose groups of OCT A-treated mice. The delayed recovery in bone marrow progenitors was also reflected in lower peripheral white blood counts after the second irradiation in 40 mg/kg OCT A-treated mice as compared to the untreated irradiated controls. This indicated that residual bone marrow effect of OCT A makes the mice more sensitive to subsequent irradiation induced injury.
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PMID:Residual hematopoietic effect in mice exposed to ochratoxin A prior to irradiation. 305 80


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