Increase In Erythrocytes Research Articles

Rheological Properties of Erythrocytes and Lipid Profiles of Blood Plasma

The study was carried out to evaluate the influence of lipid blood plasma in patients with stable angina on some rheological properties of the erythrocytes. It was found a clear increase of erythrocyte's aggregation propert ies from increase the atherogenic lipids in the blood plasma regardless from the content of high density lipoproteins. Erythrocyte deformability of red blood cells were not associate d with the plasma lipid profile.

Determination of Hematological Effects of Methanolic Leaf Extract of S. incanum in Normal Mice

Medicinal plants and herbs have been used for ages for the purposes of enhancing and maintaining health and organic resistance against body infection. This is due to their ready availability and arguably efficacious state, therefore offering an alternative remedy in enhancing hematological parameters. Various chemical constituents of Solanum incanum (Linn) are believed to possess therapeutic effects on hematological parameters, but these effects have not been subjected to systematic scientific studies to substantiate and ascertain the therapeutic claims made regarding their clinical utility. This study investigates the hematological effects of S. incanum (Linn) in normal mice. The experimental mice groups were treated with methanolic seed extracts of S. incanum (Linn) at concentrations of 50 mg/kg and 100 mg/kg orally once per two days for a period of fourteen days. Hematological parameters and indices of unclotted blood were determined using standard protocols. Phytochemicals were determined using standard protocols. Seven and fourteen days after administration of methanolic seed extracts of S. incanum at the dose level of 50 mg/kgbw, there was significant increase in erythrocytes, hemoglobin and hematocrit counts while the dose level of 100 mg/kgbw caused significant increase in hematocrit count fourteen days after administration of the extract. There was a significant increase in levels of total white blood cells, neutrophils and basophil counts seven and fourteen days after administration of the methanolic seed extract of S. incanum at the dose level of 50 mg/kgbw. The dose level of 50 mg/kgbw of methanolic seed extract of S. incanum caused a significant increase in platelet, plateletcrit, MPV, and PDW profiles after seven days. In addition phytochemical screening results showed that the seed extract of S. incanum (Linn) had phytochemicals associated with erythropoietin promoting activity, immunostimulatory activities and thrombopoietin stimulation.

Ankyrin is the major oxidised protein in erythrocyte membranes from end-stage renal disease patients on chronic haemodialysis and oxidation is decreased by dialysis and vitamin C supplementation

Chronically haemodialysed end-stage renal disease patients are at high risk of morbidity arising from complications of dialysis, the underlying pathology that has led to renal disease and the complex pathology of chronic kidney disease. Anaemia is commonplace and its origins are multifactorial, involving reduced renal erythropoietin production, accumulation of uremic toxins and an increase in erythrocyte fragility.Oxidative damage is a common risk factor in renal disease and its co-morbidities and is known to cause erythrocyte fragility. Therefore, we have investigated the hypothesis that specific erythrocyte membrane proteins are more oxidised in end-stage renal disease patients and that vitamin C supplementation can ameliorate membrane protein oxidation.Eleven patients and 15 control subjects were recruited to the study. Patients were supplemented with 2 × 500 mg vitamin C per day for 4 weeks. Erythrocyte membrane proteins were prepared pre- and post-vitamin C supplementation for determination of protein oxidation. Total protein carbonyls were reduced by vitamin C supplementation but not by dialysis when investigated by enzyme linked immunosorbent assay. Using a western blot to detect oxidised proteins, one protein band, later identified as containing ankyrin, was found to be oxidised in patients but not controls and was reduced significantly by 60% in all patients after dialysis and by 20% after vitamin C treatment pre-dialysis. Ankyrin oxidation analysis may be useful in a stratified medicines approach as a possible marker to identify requirements for intervention in dialysis patients.

Oxidative Status, Meat Quality and Fatty Acid Profile of Broiler Chickens Reared under Free-range and Severely Feed-restricted Conditions Compared with Conventional Indoor Rearing

An animal's antioxidant system is fundamentally complex aiming at finding a balance between pro-oxidative and anti-oxidative stressors in the body. To further unravel the animal's response to oxidative stressors we used free-range broilers combined with severe feed restriction as opposed to conventional broilers as a reference. At 21 days of age, 36 Ross 308 broilers were divided into three groups. The first group (I42) was raised indoors according to common practices and fed ad libitum. The second group (O42) was transferred to outdoors on a grass pasture and fed once daily 50% ad libitum. At 42 days of age, eight birds from each group were sampled. The third group (O70) was reared similar to O42 but was sampled at 70 days, having approximately the same final weight as birds I42. Compared to I42 birds, the O42 birds showed a higher and lower concentration of malondialdehyde and α-tocopherol in their plasma, respectively; indicating oxidative stress after 3 weeks of free-ranging and feed restriction. As a response, the glutathione synthesis was up-regulated as manifested by increased levels of glutathione in the liver in O42 compared with I42, and in the jejunal mucosa in O42 and O70 compared with I42, and by a three- to four-fold increase in erythrocytes in O70 compared with the other groups. Regarding meat quality, the outdoor birds showed a darker and yellower colour of breast meat as compared with those reared indoors. Muscle total fatty acid content was higher in O42 compared to I42 and O70, which was reflected in the content of individual fatty acids (mg/100g meat), whereas differences in fatty acid profile (% of total fatty acids) between groups were marginal. To conclude, free-ranging together with feed restriction elicited remarkable changes in the animal's antioxidant system, while changes in meat oxidative stability were less pronounced and more difficult to interpret.

Low-dose splenic irradiation in symptomatic congestive splenomegaly: report of five cases with literature data

BackgroundTo show effectiveness of low-dose splenic irradiation in symptomatic congestive splenomegaly.MethodsFive patients were referred to our department for symptomatic congestive splenomegaly within three years. Primary diseases were autoimmune hepatitis with liver cirrhosis (n = 2), cystic fibrosis (n = 1), granulomatous liver disease (n = 1) and Werlhof disease with liver cirrhosis (n = 1). Mean age was 54 years (range: 36–67). Patients received splenic irradiation with a total dose of 3 Gy (single dose: 0.5 Gy). One patient was re-irradiated after long-term failure with the same treatment schedule.ResultsIn four patients long term relief of splenic pain could be observed during the follow-up time of median 20 (range: 2–36) months. Four patients showed haematological response after irradiation with an increase of erythrocytes, leucocytes and/or platelets. A slightly decrease in spleen size was found in two patients.ConclusionsLow-dose splenic irradiation in symptomatic congestive splenomegaly is feasible and perhaps as effective as in lympho-and myeloproliferative malignancies regarding pain relief and haematological response.

Höhenkrankheit

Due to the decreasing partial pressure of oxygen, high altitude sickness can occur at heights over 2,500 m. This can be best avoided by slow adaptation to the altitude (acclimatization). In this way the organism adapts to the chronic hyperventilation and in the further process the oxygen content is normalized by an increase in erythrocytes. The commonest form of high altitude sickness is acute mountain sickness which is characterized by the leading symptom of headache. When additional signs of ataxia occur there is an acute danger of edema which is associated with a high mortality. Stress dyspnea, coughing and rasping breathing noises also occur by the potentially fatal high altitude pulmonary edema. All forms of high altitude sickness can be countered by a rapid descent to a height of at least 500 m. In acute mountain sickness acetazolamide can be administered (2 × 250 mg), for high altitude cerebral edema dexamethasone (3 × 4-8 mg) and for high altitude pulmonary edema nifedipine (initially 10 mg then 20 mg retard).

Smoke Exposure Has Transient Pulmonary and Systemic Effects in Wildland Firefighters

Respiratory exposure to air pollutants is associated with cardiovascular morbidity and mortality and firefighters have been shown to be at an increased risk of work-related cardiovascular events. Wildland firefighters experience intermittent, intense exposure to biomass smoke. The aim of this study was to characterize the respiratory and systemic effects of smoke exposure in wildland firefighters. Seventeen seasonal firefighters from a northeastern Ontario community were recruited at the beginning of the fire season and baseline measurements obtained; postexposure measurements were made at various times within 16 d of firefighting. Spirometric measurements showed a transient decline in forced vital capacity within 7 d of fire exposure, not evident by 8–16 d. Induced sputum showed a significant increase in macrophages and epithelial cells within 7 d, with evidence that macrophages had internalized particles; such changes were not evident in the second week following exposure. Likewise, peripheral blood analysis revealed significant increases in erythrocytes, hemoglobin, monocytes, and platelets within the first week after fire exposure, which were diminished 8–16 d in postexposure group. We conclude that acute exposure to forest-fire smoke elicits transient inflammatory responses, both in the airways and systemically. Whether these changes contribute to the observed increased risk of cardiovascular events requires further study.

Interaction of Amorphous Silica Nanoparticles with Erythrocytes in Vitro: Role of Oxidative Stress

Background/Aims: The use of engineered nanomaterials in the form of nanoparticles (NP) for various biomedical applications, as well as in consumer products, has raised concerns about their safety for human health. These NP are intended to be administered directly into the circulation following intravenous injection, or they may reach the circulation following other routes of administration such as oral or inhalation, and interact with circulating cells such as erythrocytes. However, little is known about the interaction of amorphous SiNP with erythrocytes. Methods: We studied the interaction of amorphous silica nanoparticles (SiNP) at various concentrations (1, 5, 25 and 125µg/ml) with mouse erythrocytes in vitro. Results: Incubation of erythrocytes with SiNP caused a dose-dependent hemolytic effect. Likewise, the activity of lactate dehydrogenase was dose-dependently increased by SiNP. Transmission electron microscopy analysis revealed that SiNP are taken up by erythrocytes. Lipid erythrocyte susceptibility to in vitro peroxidation measured by malondialdehyde showed a significant and dose-dependent increase in erythrocytes. SiNP also enhanced the antioxidant activities of superoxide dismutase (SOD), catalase and reduced glutathione (GSH). Moreover, SiNP increased caspase 3, triggered annexin V-binding and caused a dose-dependent increase of cytosolic calcium concentration. Conclusion: It can be concluded that SiNP cause a dose-dependent hemolytic activity and are taken up by the erythrocytes. We also found that SiNP induce the occurrence of oxidative activity, apoptosis and increase cytosolic Ca²⁺, which may explain their haemolytic activity. Our in vitro data suggest that SiNP may, plausibly, lead to anemia and circulatory disorders in vivo.

The effect of erythropoietin application on erythrocyte Na,K- ATPase activities in patients with diabetic polyneuropathy

Objectives: In this study we aimed to investigate the effects of erythropoietin administration on Na,K-ATPase enzyme activity in diabetic patients with polyneuropathy. Methods: The study was carried out at Meram Education and Research Hospital department of Nephrology and Selcuk University Meram School of Medicine Hospital department of Biochemistry, Turkey. Eleven diabetic patients with diabetic polyneuropathy and on erythropoietin therapy and ten healthy control were contributed to this study. Diabetic group was formed from the patients with polyneuropathy and on erythropoietin therapy. Erythropoietin was administered with a dose of 150 U/kg/ week to the patients. Heparinized blood samples were taken from the control group for once and from the patients for twice before and one month after the erythropoietin therapy. Erythrocyte membranes were isolated and erythrocyte membrane Na,K-ATPase enzyme activities were measured. Na,K-ATPase activities were given as mmolPi.mg.protein –1.10 min-1. Results: Na,K-ATPase enzyme activities were 2.91±0.38 μmolPi.mg.prt-1.10min-1, 1.93±0.38 μmolPi.mg.prt-1.10min-1 and 2.40±0.63 μmolPi.mg.prt-1.10min-1 in control group, and patient group before and after therapy, respectively. Na,K-ATPase enzyme activities decreased in patient group before the therapy compared to the control group and significantly increased in patient group after erythropoietin therapy compared to the basal levels of the patients. We determined 24% increase in erythrocyte Na,K-ATPase activities after one month EPO application compared to the basal levels. Conclusion: It was concluded that erythropoietin therapy could improve neuropathy and this improvement was supported with the increase in Na,K-ATPase activities which could be used as a marker.

Функціональний стан нирок у пацієнтів з онкологічними захворюваннями після введення цисплатину

During examination of kidney function under cisplastin chemotherapy in oncologic patients the nephrotoxicity of the drug have been shown during 24 hours after administration. We found that in 24 hours after injection ofcisplastin in the dose 50 mg/m2 of the surface of the body, the excretion of creatinine, sodium, potassium, osmotic active compounds and chlorides is increased more than two times, indicating for disorder in osmolality, volume and ionic regulation of kidney function. The determined peculiarities are consequences of kidney injuries, which are confirmed by an increase in erythrocyte- and leucocyteuria. We showed that alterations in homeostatic kidney function is due to damage of renal tubules. Our study necessitates a need for renal protection during the whole period of cisplastin chemotherapy.

Easy‐to‐use IEF compatible immunoaffinity purification of Erythropoietin from urine retentates

Erythropoietin (EPO) is a peptide hormone responsible for hypoxia-induced promotion of erythrocyte production. The possibility of enhancing oxygen transport through an increase of erythrocytes has led to EPO abuse in sports. Detection of exogenous EPO is most commonly done via isoelectric focusing (IEF) which is a method provided by the Technical Document TD2009EPO of the World Anti-Doping Agency (WADA). Before analysis, collected urine samples need to be concentrated 500- to 1000-fold, leading to high protein abundance in the retentates. Reduction of protein concentration through an immunoaffinity purification using ELISA wells has been successfully used prior to SDS-PAGE. This ELISA kit was used to purify samples using an IEF-compatible elution. The purification showed recovery ratios between 50 and 90% depending on substance and application volume. Application of immunopurified samples to IEF was shown to improve the quality of the gels by reducing streaks and curvatures within the lanes and bands of the gel. The result was an increase of quality for IEF gels.

The effect of natural dicarbonyls on activity of antioxidant enzymes in vitro and in vivo

Natural dicarbonyls, which may be accumulated during oxidative stress in atherosclerosis (e.g. malondialdehyde) or carbonyl stress in diabetes mellitus (glyoxal and methylglyoxal) effectively inhibited activities of commercial preparations of the antioxidant enzymes: Cu,Zn-superoxide dismutase (Cu,Zn-SOD) and Se-contained glutathione peroxidase from human and bovine erythrocytes, and also rat liver glutathione-S-transferase. After incubation of human erythrocytes with 10 mM of each investigated dicarbonyls the decrease of intracellular Cu,Zn-SOD was observed. The decreased activity of erythrocyte Cu,Zn-SOD was also detected in patients with diabetes mellitus type 2 with carbohydrate metabolism impairments but effective sugar-lowered therapy was accompanied by the increase of this enzyme activity. The increase of erythrocytes Cu,Zn-SOD activity in diabetic patients treated with metformin (which may utilize methylgly-oxal) was higher than in erythrocytes of diabetic patients subjected to traditional therapy.

Interaction of Diesel Exhaust Particles with Human, Rat and Mouse Erythrocytes in Vitro

Inhaled ultrafine (nano) particles can translocate into the bloodstream and interact with circulatory cells causing systemic and cardiovascular events. To gain more insight into this potential mechanism, we studied the interaction of diesel exhaust particles (DEP) with human, rat and mouse erythrocytes in vitro. Incubation of erythrocytes with DEP (1, 10 or 100 µg/ml) for 30 min caused the highest hemolytic effect (up to 38%) in rats, compared to small but significant hemolysis in mice (up to 2.5%) and humans (up to 0.7%). Transmission electron microscopy of erythrocytes revealed the presence of variable degrees of ultrafine (nano)-sized aggregates of DEP either internalized and/or adsorbed onto the erythrocytes in the three species. A significant amount of DEP was found in rat and mouse (but not human) erythrocytes. Lipid erythrocyte susceptibility to in vitro peroxidation measured by malondialdehyde showed a significant and dose-dependent increase in erythrocytes of rats, but not humans or mice. Unlike in human erythrocytes, total antioxidant status (TAS) and superoxide dismutase (SOD) activity in rats were significantly and dose- dependently decreased. In mouse erythrocytes, DEP caused a decreased in SOD (at 10 µg/ml) and TAS (at 100 µg/ml) activities. In conclusion, DEP caused species–dependent erythrocyte hemolysis and oxidative stress, and were either taken up and/or adsorbed onto the red blood cells. Rat (and to a lesser degree mouse) erythrocytes were susceptible to DEP. Human erythrocytes showed the highest resistance to the observed effects. These species difference should be noted when using rats and mice blood as models for humans.

CD38 expression as response of hematopoietic system to cancer

Erythrocyte and lymphocyte NAD(+) glycohydrolase levels were previously found to be elevated in cancer patients. These results were confirmed in an animal model. The administration of live Ehrlich ascites tumor cells to BALB/c mice led to increases in erythrocyte and lymphocyte NAD(+) glycohydrolase, along with tumor development. Serum samples, ascites fluid from mice with developed tumors, serum samples from cancer patients and Ehrlich cell supernatants had a similar stimulatory effect when administered to mice or when incubated with peripheric lymphocytes in culture. These increases were accompanied by the appearance of an anti-CD38 reactive band of 45 kDa in SDS-PAGE/Western blot analyses of erythrocyte ghost and lymphocyte membrane proteins. The results, supported by flow cytometry data, support previous clinical findings that an enhancement in CD38 expression occurs in the hematopoietic system during proliferative processes. Moreover, they suggest that CD38 expression is triggered at least in part by a certain cytokine(s) secreted by cancer cells. Finally, the results emphasize the prospective use of CD38 expression as a marker of tumor development and progression.

Amelioration of Radiation-Induced Hematological and Biochemical Alterations in Swiss Albino Mice by Panax ginseng Extract

This study was carried out to observe the radioprotective effect of Panax ginseng root extract (PGE) against radiation-induced hematological and biochemical alterations in blood and liver of mice. Materials and methods. Adult Swiss albino mice were exposed to 6 Gy gamma radiation in the presence (experimental) or absence (control) of PGE to study the quantitative and qualitative alterations in the blood and liver. Radiation exposure resulted in a significant decline (P<.001) in erythrocyte count, hemoglobin (Hb), and hematocrit (Hct) in peripheral blood. Maximum changes in all the parameters were observed on day 3 after irradiation. In contrast, PGE-pretreated irradiated animals showed a significant increase in erythrocyte, Hct, and Hb values compared with irradiated controls. Furthermore, a significant elevation in lipid peroxidation level over normal was recorded in irradiated control mice, whereas this increase was considerably lesser in PGE pretreated animals. Likewise, pretreatment with PGE caused a significant increase in glutathione levels in serum as well as in liver in comparison to irradiated controls. From this study, it is clearly evident that PGE provides protection against radiation-induced hematological and biochemical alterations in Swiss albino mice.

Glutathione measurements in blood samples are influenced by oxygen saturation

Heinicke et al. (2009) describe a temporary increase in erythrocyte reduced glutathione concentration by 12–20% in venous blood samples after ascent to 2,800 m above the sea level. I wonder why the authors do not present also oxidized glutathione which yield additional insight since their method (Tietze 1969) allows determination of both forms. Also, they have diYculties to interpret their result as improved antioxidant defense, since the values return to control values within 2 weeks at altitude. The cause is probably that the changes are at least partly measuring artifacts: hemoglobin that binds glutathione much better in oxygenated than deoxygenated form (Craescu et al. 1986) is precipitated before analysis; thus, an unknown amount of glutathione disappears from the supernatant. We have shown that after in vitro equilibration with diVerent oxygen pressures measured total glutathione concentrations decrease by 20% between 0 and 100% O2 saturation (Hutler et al. 2000); the decrease in reduced glutathione is even larger (30%), whereas the small fraction of oxidized glutathione increases Wvefold. As venous oxygen content falls markedly during ascent and later rises again, this might be the cause of glutathione concentration changes. The possible error is easy to correct if the authors have measured venous O2 saturations. In addition, the change in concentrations of free reduced and oxidized glutathione within the red cell after a decrease in average O2 saturation should inXuence synthesis and trans-membrane transport of this substance. Therefore, all investigations without considering these eVects do not allow clear conclusions about antioxidant defense by glutathione in blood.

Acute and sub-chronic toxicity of an aqueous extract of the leaves of Herniaria glabra in rodents

Aim of the study The present investigation was carried out to evaluate the safety of an aqueous extract of Herniaria glabra (caryophyllaceae) (HG) plant by determining its potential toxicity after acute and sub-chronic administration in rodents. Materials and Methods For the acute study, a lyophilized aqueous extract of HG plant was administered to adult IOPS OFA mice in single doses of 5–14.5 g/kg given by gavage. General behavior adverse effects and mortality were determined for up to 14 days. In the sub-chronic dose study, the HG-extract was administered orally at doses of 1, 2 and 4 g/kg daily for 90 days to Wistar rats. Selected biochemical and hematological parameters were determined after 30 and 60 days, and then at the end of 90 days of daily administration. Results In the acute study in mice, the crude aqueous extract of HG plant caused dose-dependent general behavior adverse effects and mortality. The no-observed adverse effect levels (NOAEL) of the HG extract was 5 g/kg and the lowest-observed adverse effect levels (LOAEL) was 5.5 g/kg. Mortality increased with increasing doses: the calculated LD 50 was 8.50 + 0.42 g/kg in mice. In the sub-chronic study in rats, daily oral administration of the crude HG extract for up to 90 days resulted in a significant attenuation of the normal increase in the body weight. At the highest dose, the HG-extract caused a significant increase in erythrocytes, leukocytes (WBC), platelets, and eosinophils, but it had no effect on the differential WBC counts (lymphocytes, monocytes, neutrophils and basophils). Only at the highest dose, the HG-extract caused a significant increase in serum levels of the liver enzymes, alanine aminotransferase and aspartate aminotransferase, as well as serum creatinine, indicating toxic effect of the high dose of the extract on the liver and kidney. The organ toxicity was confirmed by histopathological examination, which showed centrolobular sinusoidal congestion, disruption of the central vein and hepatocellular necrosis in the liver, and interstitial and intraglomerular congestion, tubular atrophy, and inflammation in the kidney. This study also revealed the hypoglycemic activity of the HG-extract in normoglycemic rats. The suppression of the normal weight gain and the hypoglycemic action of HG-extract should be investigated further for possible therapeutic implications. Conclusions Because of the relatively high NOAEL values in the acute study in mice, and lack of mortality or clinically significant changes in the biological (except for hypoglycemia) and hematological parameters in rats after 90 days of daily dosing, it may be concluded that the HG extract does not appear to have significant toxicity (except at high doses). In view of the doses consumed empirically in traditional medicine in Morocco, there is a wide margin of safety for the therapeutic use of Herniaria glabra.

Excessive Erythrocytosis Does Not Elevate Capillary Oxygen Delivery in Subcutaneous Mouse Tissue

Acclimatization to reduced environmental oxygen includes erythropoietin-regulated increase in erythrocytes enhancing the blood's oxygen content. However, increased hematocrit levels result in elevated blood viscosity that might impair microcirculation and tissue oxygenation. To assess this oxygen supply to the skin, the authors used erythropoietin overexpressing transgenic mice (tg6) that develop excessive erythrocytosis in an oxygen-independent manner. These animals have been previously reported to elevate their blood viscosity 4-fold. The partial oxygen pressure (pO2) distribution was evaluated in microvessels as well as in subcutaneous interstitial tissue within a dorsal skinfold chamber of resting conscious mice using automated phosphorescence quenching. Compared to wildtype (wt) animals, transgenic blood viscosity increased 4-fold but microvessel diameter was not altered. Despite sharing similar blood pO2 as the wt siblings, tg6 animals nearly doubled their oxygen content. Moreover, tg6 erythrocytes reduced hemoglobin's oxygen affinity by decreased 2,3-DPG levels and an increased Hill number. Transgenic arterioles and venules showed increased pO2 compared to wt controls whereas capillary and tissue pO2 were not altered. Excessive erythrocytosis does not elevate capillary oxygen delivery.

PBI-1402: A New Candidate for the Treatment of Anemia.

PBI-1402 is an orally active low molecular weight synthetic compound which is currently in a phase Ib/II clinical trial in patients with anemia associated with cancer and/or chemotherapy. PBI-1402 stimulates the in vitro/ex vivo proliferation and maturation of hematopoietic progenitors (erythroid and myeloid populations) with an activity comparable to EPO. Furthermore, an additive effect is observed in combination with EPO. PBI-1402 enhances the differentiation of pluripotent stem cells: CFU-GEMM, CFU-GM with a predominant effect on BFU-E. Clinical phase I study showed that PBI-1402 is devoid of significant side effects. In addition, the clinical phase I results showed statistical increase (100%, p<0.0001) of relative and absolute reticulocyte count in healthy volunteers after 21 days of oral treatment compared to placebo. Preclinical results demonstrated that PBI-1402 yields an increase in erythrocytes in the systemic circulation. In myeloblated mice that received a syngeneic bone marrow transplant, oral treatment with PBI-1402 resulted in a significant increase in peripheral erythrocyte count, hemoglobin, platelet and bone marrow erythroid progenitor cells. PBI-1402 is targeted as an adjunct to cytotoxic drugs, radiotherapy and bone marrow transplantation for the treatment of anemia.

Stimulation of Human Hematopoiesis: The Androstene Link.

5-Androstene-3β, 17β-diol (AED) is a naturally occurring member of the androstene series of steroids. In models of chemotherapy and radiation-induced mylosuppression, AED expanded hematopoietic stem and progenitor cells (HSPC), decreased need for clinical support and increased survival. We studied hematopoietic activity of AED vs. Placebo in healthy adult (20–64 years, n=9) and elderly (65–72 years, n=9) subjects. AED was safe and well tolerated. Complete blood counts were serially obtained between study days 1–56. Bone marrow (BM) samples were obtained on days -1 and 7. AED produced significant increases in average neutrophil counts (NT) and platelet counts (PLT) as compared to placebo. Adult NT significantly increased between days 2–7 (40–73%, p=0.05) and persisted through day 28 (41.5%); adult PLT increased (19.9%) by day 14, and achieved significance by day 21 (15.6%, p=0.01) and increases persisted through day 28 (19.4%, p=0.02). In elderly subjects, NT significantly increased by 56–96% (days 4–6, p=0.05) which persisted through day 28 (30.7%). Fewer elderly subjects demonstrated robust PLT responses; maximum increase in PLT was seen on day 14 (31.5%) and persisted through day 28. BM samples at day 7 showed increased cellularity in AED but not placebo-treated subjects which was consequently reflected as an increase in peripheral blood NT and PT in AE-treated subjects. BM phenotype changes and maturation potential were estimated from immunophenotyping and CFU assay in vitro. BM precursor populations were elevated in most treated subjects on day 7; this reflected an activity of AED on precursor cells that resulted in a decrease in the CD34+CD38− and CFU-F populations and an increase in erythrocyte (BFU-E, CFU-E), and granulocyte (CFU-GM) precursors and megakaryocytes. Elderly patients (but not adults) had increased levels of two angiogenic factors; vascular endothelial growth factor and plasminogen activator inhibitor-1 in plasma (day 5) and in BM (day 7). These findings suggest that AED has a regenerative role in elderly BM and that the stimulation of angiogenic factors precedes an increase in BM cellularity which in turn leads to an increase in circulating terminally differentiated blood elements.