Deferoxamine Group Research Articles

Study of the effect of different iron-chelating agents on early renal glomerular and tubular function markers in children with beta-thalassemia

Background Advances in the management of patients of beta-thalassemia major (BTM) and the advent of effective chelators have led to the discovery of many renal complications. Mechanisms of renal impairment in BTM are still not fully investigated. Chronic anemia and hypoxia, iron overload and its complications, and direct nephrotoxic effects of some chelators are the commonly used explanations. Objectives In this cross-sectional study, the aim was to investigate the prevalence of renal impairment in patients with BTM using some of both conventional and early markers of glomerular and tubular renal function and to investigate the relation between them and iron overload (s. ferritin) and the use of a specific chelator. Patients and methods The study included 60 transfusion-dependent patients with BTM without overt renal disease or risk factors, for example, diabetes mellitus, and 30 age-matched and sex-matched healthy children as a control group (group C). Patients were divided into two equal groups according to type of chelator: group A children receiving standard deferoxamine (DFO) and/or deferiprone and group B children receiving deferasirox (new treatment). Serum levels of ferritin, creatinine, and blood urea nitrogen; albumin/creatinine ratio (ACR) in urine; estimated glomerular filtration rate using Schwartz formula; urinary beta 2 microglobulin (UB2MG); and urinary calcium/creatinine ratio were measured in all patients and healthy control children. Results Serum creatinine was within the normal range in most of the patients, and no significant differences were found between the two thalassemic groups and the control group (P=0.473). ACR in urine and UB2MG were significantly higher in the two thalassemic groups, and the deferasirox group showed significantly higher levels than both DFO and/or deferiprone group and control group (P1=0.05 and P2=0.005, respectively, for ACR and P1=0.025 and P2=0.000, respectively, for UB2MG). UB2MG was abnormally high in 67 and 76% of the DFO and/or deferiprone group and deferasirox group, respectively, followed by microalbuminuria (16 and 30%, respectively). Glomerular hyperfiltration was prevalent, but there were no significant differences in the median of the three groups (P=0.766). Hypercalciuria was also prevalent in the two thalassemic groups with abnormally elevated urinary calcium/creatinine ratio in 30% of both groups but without significant differences in the median of the three groups (P=0.123). Serum ferritin was significantly positively correlated with ACR (P=0.002) and with UB2MG (P=0.000). Conclusions ACR can be used as an early marker of glomerular function. Deferasirox use is probably safe in the usual doses in low-risk patients, keeping into consideration that high doses of deferasirox cause disruption of the renal function.

Treatment With Topical Deferoxamine Improves Cutaneous Vascularity and Tissue Pliability in an Irradiated Animal Model of Tissue Expander-Based Breast Reconstruction.

Postmastectomy radiation therapy is an important component of the multimodality approach to later-stage breast cancers. Unfortunately, despite its proven survival benefits, postmastectomy radiation therapy is deleterious to the skin and soft tissue, causing increased complications and worse aesthetic outcomes after breast reconstruction.There is currently no effective pharmaceutical agent to mitigate the soft tissue fibrosis and hypovascularity associated with soft tissue radiation. We hypothesized that a novel topical formulation of deferoxamine (DFX) will result in improved cutaneous vascularity and soft tissue pliability in an animal model of irradiated tissue expander-based breast reconstruction. This study consisted of 16 hairless rats divided into 4 equal groups: a control group (expander only), a tissue expanded and irradiated group, a tissue expanded + DFX group, and a tissue expanded/irradiated/DFX group. A novel topical formulation of DFX consisted of reconstituted drug dissolved in agents designed to enhance dermal penetrance. Vessels per high-power field (vHPF) were quantified histologically; micro-computed tomography angiography was used to assess vessel volume fraction (VVF) and vessel length density. Irradiated skin had less vascularity compared with control (3.81 vHPF vs 8.25 vHPF, P = 0.03; 0.79% VVF vs 1.53% VVF, P = 0.06). Treatment of irradiated skin with topical DFX reversed these effects, resulting in vascular findings similar to the control group histologically (7.94 vHPF vs 8.25 HPF, P = 0.985) and via micro-computed tomography angiography (1.05% VVF vs 1.53% VVF, P = 0.272). Similarly, radiation resulted in less volume expansion compared with controls (0.72 vs 0.8 mL, P = 0.04), whereas treatment with topical DFX reversed this effect, allowing for an expansion volume similar to the control group (0.81 vs 0.80 mL, P = 0.999). In an animal model of irradiated tissue expander-based breast reconstruction, treatment with topical DFX improved the cutaneous vascularity and tissue pliability, resulting in vascular density and final tissue expansion volumes similar to those found in the nonirradiated control group. Topical DFX may be an effective agent for the treatment of soft tissue radiation injury; future studies are indicated to further characterize this novel drug formulation.

Comparative Effects of Iron Chelators on the Transfusion-Dependent Beta-Thalassemia Patients

This prospective study assessed the quality of life of patients with transfusion-dependent beta-thalassemia receiving three different iron chelation treatments. Patients enrolled were receiving one of the following chelation therapies: Group-I: deferoxamine (n=21), Group-II: deferasirox (n=75) and Group-III: deferoxamine in combination with deferiprone (n=39). The three groups were compared in terms of their quality of life, satisfaction and adherence to treatment, control of their health, and self-esteem through the completion of five questionnaires. A higher percentage of patients receiving deferoxamine felt that their treatment negatively influenced their body and skin appearance and limited their ability to work, attend school, and perform daily tasks (P=.0.0066). The adherence to treatment rate and self-esteem were the lowest in the deferoxamine group (P<0.05). The deferoxamine group also had the lowest physical component summary score in the SF-36 questionnaire (P=0.014). This study suggests that the quality of life of beta-thalassemia patients receiving chelation therapy is dependent on the type of iron chelation treatment they receive. The study provides insight into important factors associated with the quality of life of these patients, which are essential for developing a more suitable clinical support team and counseling in order to maximize the treatment benefits for these patients in daily clinical practice.TAJ 2013; 26: 14-19

Topical Deferoxamine Alleviates Skin Injury and Normalizes Atomic Force Microscopy Patterns Following Radiation in a Murine Breast Reconstruction Model.

Breast cancer is most commonly managed with a combination of tumor ablation, radiation, and/or chemotherapy. Despite the oncologic benefit of these treatments, the detrimental effect of radiation on surrounding tissue challenges the attainment of ideal breast reconstruction outcomes. The purpose of this study was to determine the ability of topical deferoxamine (DFO) to reduce cutaneous ulceration and collagen disorganization following radiotherapy in a murine model of expander-based breast reconstruction. Female Sprague-Dawley rats (n = 15) were divided into 3 groups: control (expander), XRT (expander + radiation), and DFO (expander + radiation + deferoxamine [DFO]). Expanders were placed in a submusculocutaneous plane in the right upper back and ultimately filled to 15 mL. Radiation was administered via a fractionated dose of 28 Gy. Deferoxamine was delivered topically for 10 days following radiation. After a 20-day recovery period, skin ulceration and dermal type I collagen organization were analyzed. Compared with control, the XRT group demonstrated a significant increase in skin ulceration (3.7% vs 43.3%, P = 0.00) and collagen fibril disorganization (26.3% vs 81.8%, P = 0.00). Compared with the XRT group, treatment with topical DFO resulted in a significant reduction in ulceration (43.3% vs 7.0%, P = 0.00) and fibril disorganization (81.8% vs 15.3%, P = 0.00). There were no statistical differences between the control and DFO groups in skin ulceration or collagen disorganization. This study suggests topical DFO is capable of reducing skin ulceration and type I collagen fibril disorganization following radiotherapy. This novel application of DFO has potential to enhance expander-based breast reconstruction outcomes and improve quality of life for women suffering the devastating effects of breast cancer.

SF-deferoxamine, a bone-seeking angiogenic drug, prevents bone loss in estrogen-deficient mice.

Deferoxamine (DFO) possesses a good chelating capability and is therefore used for the clinical treatment of ion deposition diseases. Increasing evidence shows that DFO can inhibit the activity of proline hydroxylase (PHD) by chelating iron, resulting in hypoxia-induced factor (HIF) signaling activation and angiogenesis promotion. However, clinical evidence indicates that a high concentration of DFO could be biotoxic due to its enrichment in related organs. Thus, we established a new compound by conjugating DFO with the bone-seeking agent iminodiacetic acid (IDA); the new agent is called SF-DFO, and we verified its promotion of HIF activation and tube formation in vivo. After confirming the bone-seeking property of SF-DFO in the femur and vertebra of both male and female mice and comparing it to that of DFO, we analyzed the protective effect of DFO and SF-DFO in an ovariectomized (OVX) mouse model. The serum CTX-I level revealed no influence of DFO and SF-DFO on osteoclast activity, but the blood vessels and osteoblasts in the metaphysis were more abundant after SF-DFO treatment, which resulted in a greater protective effect against trabecular bone loss compared to the DFO group. Additionally, the cortical parameters and bone strength performance were identical between the DFO and SF-DFO groups. However, the diffuse inflammatory response in the liver and spleen that occurred after DFO injection was not observed in the SF-DFO group. Thus, with reduced biotoxicity and an equivalent bone-seeking capability, SF-DFO may be a better choice for the prevention of vascular degradation-induced osteoporosis.

Deferoxamine-Soaked Suture Improves Angiogenesis and Repair Potential After Acute Injury of the Chicken Achilles Tendon.

Background:A major obstacle to the treatment of soft tissue injuries is the hypovascular nature of the tissues. Deferoxamine (DFO) has been shown to stimulate angiogenesis by limiting the degradation of intracellular hypoxia-inducible factor 1–alpha.Hypothesis:DFO-saturated suture would induce angiogenesis and improve the markers of early healing in an Achilles tendon repair model.Study Design:Controlled laboratory study.Methods:Broiler hens were randomly assigned to the control (CTL) group or DFO group (n = 9 per group). The right Achilles tendon was partially transected at its middle third. The defect was surgically repaired using 3-0 Vicryl suture soaked in either sterile water (CTL group) or 324 mM DFO solution (DFO group). All animals were euthanized 2 weeks after the injury, and the tendon was harvested. Half of the tendon was used to evaluate angiogenesis via hemoglobin content and tissue repair via DNA content and proteoglycan (PG) content. The other half of the tendon was sectioned and stained with hematoxylin and eosin, safranin O, and lectin to evaluate vessel density.Results:Hemoglobin content (percentage of wet tissue weight) was significantly increased in the DFO group compared with the CTL group (0.081 ± 0.012 vs 0.063 ± 0.016, respectively; P = .046). DNA content (percentage of wet tissue weight) was also significantly increased in the DFO group compared with the CTL group (0.31 ± 0.05 vs 0.23 ± 0.03, respectively; P = .024). PG content (percentage of wet tissue weight) was significantly decreased in the DFO group compared with the CTL group (0.26 ± 0.02 vs 0.33 ± 0.08, respectively; P = .035). Total chondroid area (number of vessels per mm2 of tissue area evaluated) was significantly decreased in the DFO group compared with the CTL group (17.2 ± 6.6 vs 24.6 ± 5.1, respectively; P = .038). Articular zone vessel density (vessels/mm2) was significantly increased in the DFO group compared with the CTL group (7.1 ± 2.5 vs 2.1 ± 0.9, respectively; P = .026).Conclusion:The significant increase in hemoglobin content as well as articular zone vessel density in the DFO group compared with the CTL group is evidence of increased angiogenesis in the fibrocartilaginous region of the tendon exposed to DFO. The DFO group also displayed a significantly greater level of DNA and significantly lower level of PG, suggesting enhanced early healing by fibrous tissue formation.Clinical Relevance:Stimulating angiogenesis by DFO-saturated suture may be clinically useful to improve healing of poorly vascularized tissues.

Abstract 2911: The propitious dual roles of deferoxamine in head and neck cancer management

Abstract Introduction: For head and neck cancer survivors, radiotherapy (XRT) improves survivorship at a cost of impaired quality of life. XRT-induced pathologic fractures (fxs) and associated nonunions are devastating iatrogenic sequelae associated with microvascular damage in bone, yet there are no pharmacologic strategies to prevent or treat these maladies. Deferoxamine (DFO), an FDA-approved iron chelator, has been extensively investigated for its ability to promote tissue vascularization through upregulation of the HIF-1α pathway. Our laboratory has previously demonstrated improved fx healing and prevention of nonunions in radiated bone utilizing localized DFO administration. However, the role of DFO in head and neck squamous cell carcinoma (HNSCC) tumorigenesis is currently unknown. While iron is essential for normal cell proliferation, excessive iron is associated with multiple oncogenic pathways. Thus, localized iron chelation may have beneficial antitumorigenic properties. Elucidating the role of iron metabolism and correlations between iron chelation and angiogenic signaling may offer opportunities for diagnostic and treatment purposes, while simultaneously improving tissue engineering efforts for HNSCC survivors. Methods: We surveyed the UALCAN survivorship data base for iron-related genes in HNSCC. In vitro, established MDA1986 (HPV+) and UMSCC108 (HPV-) cell lines were grown in culture. The effects of DFO were probed on 3-D tumorspheres. HIF-1α was examined by IHC, and Western blot (WB) was used to elucidate iron mediators. In vivo, MDA-1986 buccal xenografts were developed in Nu/Nu mice. Control, DFO, and XRT groups were generated, and DFO and XRT were administered as previously described. IVIS imaging and tumor volumes were used to monitor growth. UALCAN data guided the selection of iron-regulatory proteins identified by WB in excised tumors. Results: TFRC and FTH-1 were highly upregulated, suggesting that dysregulation of iron metabolism contributes to HNSCC development. In vitro, we observed a dose-dependent decrease in 3-D tumorsphere formation and no alterations in HIF-1α expression. WB demonstrated TFRC downregulation in response to 100µM DFO in both HPV+ and - cells. In vivo, a significant decrease in tumor growth and radiance was observed with DFO treatment (comparable to XRT) when compared to untreated controls. Excised tumor WB demonstrated downregulation of TFRC, identifying it as a pivotal indicator of response to iron-chelation therapy. Conclusion: In vitro and in vivo studies reveal that DFO exhibits antitumorigenic effects, and suggest that HIF-1α is not affected by iron chelation in HNSCC cells. Moreover, TFRC was identified as a biomarker for indicating treatment response. Our findings signify that localized DFO may have antitumorigenic effects, in addition to the previously established regenerative therapeutic effects for the treatment of XRT-induced bone pathologies. Citation Format: Alexis Donneys, Chitra Subramanian, Jeremy Lynn, Kevin Urlaub, Kevin Kovatch, Halil S. Uygur, Mark S. Cohen, Steven R. Buchman. The propitious dual roles of deferoxamine in head and neck cancer management [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2911.

Histologic Improvements in Irradiated Bone Through Pharmaceutical Intervention in Mandibular Distraction Osteogenesis

Despite the relative surgical ease and reduced donor-site morbidity of distraction osteogenesis (DO) in comparison with free tissue transfer, DO is currently precluded as a reconstructive option for head and neck cancer (HNC) patients because of the destructive effects of radiotherapy (XRT). This study investigates the ability of a novel combined therapy (CT) of radioprotective amifostine (AMF) and angiogenic deferoxamine (DFO) to mitigate XRT-induced bone injury in a murine model of DO. Thirty male Sprague-Dawley rats were divided into 5 groups: DO (primary control), XRT (secondary control), AMF, DFO, and CT. With the exclusion of the DO group, all rats were administered a fractionated, human-equivalent XRT dose of 35Gy, comparable with 70Gy administered to HNC patients clinically. All groups underwent mandibular osteotomy and distraction to 5.1mm. After euthanasia administration on postoperative day 40, the mandibles were sectioned and stained with Gomori trichrome.Osteocyte number, bone volume, and osteoid volume were compared between all groups by analysis of variance (P<.05). All rats survived and were included in the final analysis. The XRT group exhibited substantial bone injury, evidenced by a decreased osteocyte number and bone volume, as well as an increase in immature osteoid volume, compared with DO controls.The AMF, DFO, and CT groups showed significant increases in osteocyte proliferation compared with the XRT group and were not statistically different from the DO group. Notably, the CT group showed remediation of XRT-induced impairment of bone maturation and exhibited significantly greater bone volume and reduced osteoid volume in comparison with all groups. Combined AMF and DFO treatment showed the capacity to remediate the deleterious effects of XRT, restore cellularity to nonirradiated levels, and surpass all groups in mature bone formation. Although further investigations of AMF and DFO are warranted, this study provides preliminary support for the potential use of DO in HNC patients through pharmaceutical facilitation of irradiated bone healing.

Abstract TP112: Differential Effects of Deferoxamine Treatment on Neurological Deficits in Young Diabetic Female Animals After Embolic Stroke

Premenopausal women have lower stroke risk and mortality than age-matched men, a finding replicated in preclinical models. However, we recently reported that female diabetic rats developed greater hemorrhagic transformation (HT) after embolic stroke and thrombolysis with tPA, leading to poor short term outcomes, despite no change in infarct size. Given that iron chelation therapy with deferoxamine (DFX) in the recovery period improves long term functional outcome in male diabetic rats that develop HT after embolic stroke, the current study tested the hypothesis that DFX will improve neurological recovery in diabetic females, especially with tPA combined treatment. Control and type 2 diabetic female animals were subjected to embolic middle cerebral artery occlusion. DFX (100 mg/kg) or vehicle was given every 12 h for 7 days after stroke. tPA (1 mg/kg) was given at 90 min post-occlusion to diabetes group. The composite score (Bederson’s score and beam walk), adhesive removal (ART) and novel object recognition (NOR) were assessed at day 3, 7 and 14 after the surgery. DFX improved sensorimotor deficits in both groups, and the combination with tPA in the diabetes group had a similar effect to DFX alone. Control vehicle group regained cognitive function but there was no change in diabetic animals which had deficits at baseline. Interestingly, cognitive deficits increased in the control DFX and diabetes tPA+DFX group. These results suggest that DFX treatment may improve the long term sensorimotor deficits in diabetic females after stroke but the impact on cognitive outcomes needs further evaluation.

Comparison of the Mean Serum Ferritin Levels in Thalassaemia Major Patients after Giving Deferasirox and Deferoxamine

Objective: To compare the mean serum ferritin levels in thalassaemia major patients after giving deferasirox and deferoxamine. This is a randomised control trial conducted at the Department of Paediatrics, Civil Hospital, Karachi from 29th January 2014 to 28th July 2014.&#x0D; Methods: A total of 160 patients of either gender, with age between 1 to 14 years, who received blood transfusion at least once a month for one year and had serum ferritin &gt;1000 mcg/L were included. Each enrolled patient was randomly allocated to group-A (deferoxamine) or group-B (deferasirox). Pre- and post-treatment iron profile was done in both groups to assess the iron status in the body. De- scriptive statistics were applied to calculate mean and standard deviation for the quantitative vari- ables. Frequencies and percentages were calculated for the qualitative variables. Independent sample t-test was applied to compare mean change in serum ferritin level in both groups. Effect modifiers were controlled by stratification. Paired t-test was also applied post stratification and p- value £ 0.05 was considered as significant.&#x0D; Results: Overall there were 96 male and 64 female patients. The overall mean age of study subjects was 7.54 ± 4.21 years. In the deferasirox group, mean age was 6.35 ± 4.11 years, mean weight wasv18.01 ± 6.74 kg, mean height was 102.04 ± 19.48 cm, and mean duration of transfusion was 7.48 ± 3.99 months/year. In the deferoxamine group, mean age was 8.74 ± 3.97 years, mean weight was 20.44 ± 6.77 kg, mean height was 102.19 ± 20.85 cm, and mean duration of transfusion was 8.14 ± 3.55 months/year. In the deferasirox group, before treatment mean serum ferritin level was 1385.73 ± 117.01 mcg/L. After treatment mean serum ferritin level was reduced to 1047.59 ± 117.08 mcg/L. In the deferoxamine group, before treatment mean serum ferritin level was 1362.58 ± 134.42 mcg/L. Af- ter treatment mean serum ferritin level was reduced to 1124.36 ± 134.52 mcg/L. Post-treatment the serum ferritin level between two groups was significantly different with p&lt;0.01. The mean difference in serum ferritin level in pre- and post-treatment among two groups was highly significant with p&lt;0.01.&#x0D; Conclusion: Deferasirox is an effective, safe and tolerable chelation therapy for the treatment of thalassaemia major with iron overload due to its ability to provide constant chelation coverage and potential to improve compliance.

Activation of the molecular and functional effects of Nrf2 against chronic iron oxide nanorod overload-induced cardiotoxicity.

Reactive oxygen species have a significant role in the pathogenesis of iron oxide nanorod (IONR) overload-induced organ toxicity in some organs such as the lungs. Green tea induces upregulation of phase II antioxidant enzymes that are transcriptionally organized by the nuclear factor (erythroid-derived 2)-like 2 (Nrf2) that when activated antagonize the oxidative stress induced by IONR overload that causes cardiotoxicity. The aim of the present study was to determine whether treatment of cardiotoxicity with iron chelators (deferiprone (DFP) or deferoxamine (DFO)) alone or in combination with phytochemical activation of Nrf2 (green tea) can protect cardiomyocytes from IONR overload-induced cardiotoxicity. One hundred five rats were distributed into seven groups: two control groups (non-IONR-overloaded and IONR-overloaded) and five IONR-overloaded groups such as a green tea group, DFP group, DFP combined with green tea group, DFO group, and DFO combined with green tea. Blood samples and cardiac tissues were obtained for estimation of total iron-binding capacity, ratio of myocardial 8-hydroxy-2'-deoxyguanosine/myocardial 2-deoxyguanosine, thiobarbituric acid reactive substances, glutathione (GSH) contents, and histopathological examination. The results showed mild histopathological changes in the heart and a significant decrease in all biochemical parameters, except for myocardial GSH, in the DFP group. The addition of green tea improved the biochemical and histopathological results compared with chelators alone.

Abstract: Implantable Deferoxamine Facilitates Non-Vascularized Grafting in Irradiated Bone

INTRODUCTION: The goal of this proposal is to therapeutically reverse the damaging effects of radiotherapy on bone formation and healing to enable non-vascularized grafting in irradiated bone. Utilizing a rodent model of mandibular bone grafting, we quantified metrics of diminished graft take and bone healing in response to radiation treatment. Subsequently, we utilized implantable deferoxamine (DFO)-an angiogenic stimulant, to reverse these radiation-induced detriments. We hypothesized that the addition of our proposed therapy, would evidence quantifiable degrees of remediation on the process of tissue regeneration, graft incorporation and bone healing. METHODS: Male Lewis rats received a human equivalent dose of radiotherapy (7Gy/d x 5d) to left hemi-mandibles. After recovery, a circular trephine burr (6mm) was utilized to create a critical size defect just posterior to the third molar, and a bone graft was harvested from the right hemi-mandible of the same animal and secured with a custom PLA resorbable plate. Three groups (n=8/group) of animals were investigated: Control, (irradiated) XRT and irradiated + implantable deferoxamine (DFO). Mandibles were imaged at 14, 40 and 60 days with in vivo µCT, and a 60-day healing period was allowed prior to further outcomes testing. Bony union was judged clinically by 3 blinded reviewers on a scale from 0 to 4, representing the approximate percentage of robust union formation along the circular graft-recipient site interface (e.g. 1=25%, 4=100%). Statistical comparisons were conducted with ANOVA (p<0.05). RESULTS: We observed a significant diminution of bone graft healing after radiotherapy. At 60 days, the bone volume fraction (BVF) of the XRT group decreased by 20% (p=0.001), and exhibited lower bony union scores when compared to control (p=0.005). With the addition of DFO, these findings were largely remediated. At 60 days, the BVF improved upon the XRT BVF by 12% (p=0.025), and was not different than control (p=0.282). In addition, the bony union scores of the implanted DFO group significantly improved from XRT levels (p=0.05), and were not different than control (p=0.200). CONCLUSION: Implantable DFO strongly remediates the effects of radiation on non-vascularized bone graft incorporation and healing as measured by micro-densitometry and bony union analysis. These observations are promising with regards to the potential utility of this therapy to enhance bone graft incorporation in the irradiated mandible for head and neck cancer survivors.

The effect and relative mechanism of deferoxamine on bone mass in ovariectomized mice companied with iron accumulation

Objective To observe the effect of iron chelator deferoxamine mesylate (DFO) on ovariectomized mice plus iron intervention, and to explore the relative mechanism. Methods 8-weeks old C57BL/6J female mice were underwent oophorectomy and randomly divided into ovariectomized (OVX) group, ovariectomized+ iron intervention group (OVX+ Fe group) and ovariectomized+ iron+ deferoxamine group (OVX+ Fe+ DFO group). After two weeks, the OVX+ Fe group mice and the OVX+ Fe+ DFO group mice were treated with 0.12 g/kg per week ferric ammonium citrate intervention four weeks via intraperitoneal injection three times a week, while the OVX group mice were treated with saline via the same methods and frequency. Afterwards, the OVX+ Fe+ DFO group mice were administrated with 4 000 mg/kg per week of DFO for two weeks via intraperitoneal injection twice a day, while mice in the other two groups administrated with saline in the same manner and frequency. Mice were sacrificed at the end of the administration. The serum ferritin, osteoprotegerin (OPG) or receptor ativator for nuclear factor-κB ligand (RANKL) level were detected by enzyme-linked immuno sorbent assay. Distal femur three-dimensional analysis was detected by micro computed tomography (Micro-CT). The prussian blue staining was conducted to observe bone iron deposition in femur. Real-time quantitative polymerase chain reaction (Real-time PCR) was conducted to analyze the expression of OPG and RANKL in bone tissue. Results The serum ferritin in OVX+ Fe group [(408.90±17.20) μg/ml] was significantly higher than the other groups [OVX group (87.53±3.73) μg/ml and OVX+ Fe+ DFO group (162.30±10.58) μg/ml, respectively] (P=0.000). Besides, prussian blue staining showed that the iron deposition in bone of OVX+ Fe group mice was the most, and in bone of OVX group mice was the least. These results suggested that iron accumulation could increase systemic and local bone tissue iron accumulation, while DFO could reduce the iron accumulation no matter in serum and in local bone tissue. The bone mass in the OVX+ Fe group [(0.09±0.02) mg/mm3] was significantly lower than the OVX groups [(0.13±0.01) mg/mm3,P=0.000]. However, after administrated with DFO, the bone mass in the OVX+ Fe+ DFO group [(0.12±0.01) mg/mm3] was significantly increased compared with OVX+ Fe group [(0.09±0.02) mg/mm3,P=0.000]. The bone tissue OPG expression in OVX+ Fe group (0.75±0.15) was down regulated when compared with the OVX group (1.00±0.20, P=0.019, 0.012). But after administrated with DFO (0.89±0.15), the bone tissue OPG expression was increased significantly compared with the OVX+ Fe group (0.75±0.15, P=0.000). The bone tissue RANKL expression and RANKL/OPG ratio in OVX+ Fe group (2.20±0.12 and 2.80±0.40, respectively) was up regulated when compared with the OVX group (1.00±0.13 and 1.00±0.50, respectively, P=0.000). But after administrated with DFO, the bone tissue RANKL expression (1.3±0.2) and RANKL/OPG ratio (1.4±0.3) was decreased significantly compared with the OVX+ Fe group (P=0.000, 0.015). The levels of OPG and RANKL in serum were as the same as the results of real-time PCR (P=0.000, 0.017). Conclusion Iron accumulation decreased bone mass in OVX mice through affecting the RANKL/receptor ativator for nuclear factor-κB (RANK)/OPG axis, while DFO might reduce iron accumulation and partially restored this effect. Key words: Iron accumulation; Desferrioxamine mesylate; Postmenopausal osteoporosis; Receptor ativator for nuclear factor-κB ligand/receptor ativator for nuclear factor-κB/osteoprotegerin axis

* Hypoxia Biomimicry to Enhance Monetite Bone Defect Repair.

Tissue hypoxia is a critical driving force for angiogenic and osteogenic responses in bone regeneration and is, at least partly, under the control of the Hypoxia Inducible Factor-1α (HIF-1α) pathway. Recently, the widely used iron chelator deferoxamine (DFO) has been found to elevate HIF-1α levels independent of oxygen concentrations, thereby, creating an otherwise normal environment that mimics the hypoxic state. This has the potential to augment the biological properties of inorganic scaffolds without the need of recombinant growth factors. This pilot study investigates the effect of local delivery of DFO on bone formation and osseointegration of an anatomically matched bone graft substitute, in the treatment of segmental bone defects. Three-dimensional printing was used to create monetite grafts, which were implanted into 10 mm midshaft ulnar defects in eight rabbits. Starting postoperative day 4, one graft site in each animal was injected with 600 μL (200 μM) of DFO every 48 h for six doses. Saline was injected in the contralateral limb as a control. At 8 weeks, micro-CT and histology were used to determine new bone growth, vascularity, and assess osseointegration. Six animals completed the protocol. Bone metric analysis using micro-CT showed a significantly greater amount of new bone formed (19.5% vs. 13.65% p = 0.042) and an increase in bone-implant contact area (63.1 mm2 vs. 33.2 mm2 p = 0.03) in the DFO group compared with control. Vascular channel volume was significantly greater in the DFO group (20.9% vs. 16.2% p = 0.004). Histology showed increased bone formation within the osteotomy gap, more bone integrated with the graft surface as well as more matured soft tissue callus in the DFO group. This study demonstrates a significant increase in new bone formation after delivery of DFO in a rabbit long bone defect bridged by a 3D-printed bioresorbable bone graft substitute. Given the safety, ease of handling, and low expense of this medication, the results of this study support further investigation into the use of iron chelators in creating a biomimetic environment for bone healing in segmental bone loss.

Deferoxamine’s Influence on Iron Metabolism, the Rheological Properties of Blood, Endothelial Dysfunction in an Experimental Model of Ischemia/Reperfusion

Objectives. Prevention of violations of microcirculation should take into account the massive entry of hemolysis products into the bloodstream and the related subsequent activation of free radical oxidation. Results. By simulating ischemia/reperfusion on rats we demonstrated the positive effect of deferoxamine on iron metabolism parameters (higher levels of transferrin, less ferritin and free iron, which received the drug group), also observed a decrease in the concentration of von Willebrand factor, as a measure of endothelial dysfunction. Blood viscosity parameters in the deferoxamine group was the closest to the control group parameters. Conclusion. Thus, we can conclude about the positive effect of deferoxamine on the parameters of iron metabolism, microcirculation and blood rheology in critical conditions involving ischemia/reperfusion.

Comparison of iron chelation effects of deferoxamine, deferasirox, and combination of deferoxamine and deferiprone on liver and cardiac T2* MRI in thalassemia maior.

Background: Cardiac complications due to iron overload are the most common cause of death in patients with thalassemia major. The aim of this study was to compare iron chelation effects of deferoxamine, deferasirox, and combination of deferoxamine and deferiprone on cardiac and liver iron load measured by T2* MRI.Methods:In this study, 108 patients with thalassemia major aged over 10 years who had iron overload in cardiac T2* MRI were studied in terms of iron chelators efficacy on the reduction of myocardial siderosis. The first group received deferoxamine, the second group only deferasirox, and the third group, a combination of deferoxamine and deferiprone. Myocardial iron was measured at baseline and 12 months later through T2* MRI technique.Results:The three groups were similar in terms of age, gender, ferritin level, and mean myocardial T2* at baseline. In the deferoxamine group, myocardial T2* was increased from 12.0±4.1 ms at baseline to 13.5±8.4 ms at 12 months (p=0.10). Significant improvement was observed in myocardial T2* of the deferasirox group (p<0.001). In the combined treatment group, myocardial T2* was significantly increased (p<0.001). These differences among the three groups were not significant at the 12 months. A significant improvement was observed in liver T2* at 12 months compared to baseline in the deferasirox and the combination group.Conclusion: In comparison to deferoxamine monotherapy, combination therapy and deferasirox monotherapy have a significant impact on reducing iron overload and improvement of myocardial and liver T2* MRI.

Health-related Quality of Life in Children and Adolescents With β-Thalassemia Major on Different Iron Chelators in Basra, Iraq.

Few studies have investigated the quality of life of children with thalassemia in the Middle East or Mediterranean region, especially Iraq. Therefore, this study was performed to assess the health-related quality of life (HRQoL) of patients with β-thalassemia major compared with healthy children and adolescents in the same age group and to evaluate the effects of different iron chelators on HRQoL measurements. A case-control study was performed on patients with β-thalassemia major registered at the Center for Hereditary Blood Diseases in Basra from February 2012 through July 2013. The group included children and adolescents aged 2 to 17 years old. HRQoL was assessed using the Pediatric Quality of Life (PedsQL) Generic Core Scale questionnaire, version 4.0, for children 2 to 12 years old and the Short Form-36 health survey questionnaire, version 2 (SF-36v2), for children and adolescents aged 13 to 17 years old. A total of 209 age-matched and sex-matched children and adolescents were included in the control group. The study did not find a significant difference in PedsQL scores among different age groups or different iron chelators, whereas there were significant differences in all of the SF-36v2 domains, with the best quality of life observed in the deferasirox group, followed by the deferoxamine group and the combined therapy group (P<0.05). The use of deferasirox among patients aged 13 to 17 years old was associated with higher SF-36v2 scores than in the other groups (P<0.05). However, for younger patients, the PedsQL scores were not significantly different for different iron chelators. The use of oral deferasirox significantly improved the quality of life of adolescents with β-thalassemia major. However, this effect was less prominent among patients aged 2 to 12 years old.

Deferoxamine released from poly(lactic-co-glycolic acid) promotes healing of osteoporotic bone defect via enhanced angiogenesis and osteogenesis.

The regeneration capacity of osteoporotic bones is generally lower than that of normal bones. Current methods of osteoporotic bone defect treatment are not always satisfactory. Recent studies demonstrate that activation of the hypoxia inducible factor-1α (HIF-1α) pathway, by genetic methods or hypoxia-mimicking agents, could accelerate bone regeneration. However, little is known as to whether modulating the HIF-1α pathway promotes osteoporotic defect healing. To address this problem in the present study, we first demonstrated that HIF-1α and vascular endothelial growth factor expression levels are lower in osteoporotic bones than in normal bones. Second, we loaded poly(Lactic-co-glycolic acid) (PLGA) with the hypoxia-mimetic agent deferoxamine (DFO). DFO released from PLGA had no significant effect on the proliferation of mesenchymal stem cells (MSCs); however, DFO did enhance the osteogenic differentiation of MSCs. In addition, DFO upregulated the mRNA expression levels of angiogenic factors in MSCs. Endothelial tubule formation assays demonstrate that DFO promoted angiogenesis in human umbilical vein endothelial cells. Third, untreated PLGA scaffolds (PLGA group) or DFO-containing PLGA (PLGA + DFO group) were implanted into critically sized osteoporotic femur defects in ovariectomized rats. After treatment periods of 14 or 28 days, micro-CT, histological, CD31 immunohistochemical, and dynamic bone histomorphometric analyses showed that DFO dramatically stimulated bone formation and angiogenesis in a critically sized osteoporotic femur defect model. Our in vitro and in vivo results demonstrate that DFO may promote the healing of osteoporotic bone defects due to enhanced angiogenesis and osteogenesis. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2515-2527, 2016.

Effect of deferoxamine on autophagy in hippocampal neurons after exploratory laparotomy in aged rats

Objective To investigate the effect of deferoxamine on autophagy in hippocampal neurons after exploratory laparotomy in aged rats. Methods Forty-four healthy male Sprague-Dawley rats, aged 18 months, weighing 500-600 g, were randomly divided into 2 groups(n=22 each)using a random number table: operation group(group O)and deferoxamine group(group D). In group D, deferoxamine 50 mg/kg was injected intraperitoneally once a day for 14 consecutive days, while the equal volume of normal saline was given instead in group O. Exploratory laparotomy was performed at 2 h after administration on 7th day.Learning and memory function was assessed using Morris water maze test which was performed before operation and at 1, 3, and 7 days after operation.The escape latency and swimming distance were recorded.The rats were sacrificed, and the hippocampi were removed for determination of the expression of Beclin-1, ferritin H and ferritin L by Western blot. Results Compared with the value before operation, the escape latency and swimming distance were significantly prolonged at each time point after operation in group O(P 0.05). Compared with group O, the escape latency and swimming distance were significantly shortened, the expression of Beclin-1 was up-regulated, and the expression of ferritin H and ferritin L was down-regulated at each time point after operation in group D(P<0.05). Conclusion Deferoxamine reduces postoperative cognitive dysfunction probably through inducing autophagy in hippocampal neurons, degrading ferritin and inhibiting iron overload in the brains of aged rats. Key words: Deferoxamine; Cognitive disorders; Hippocampus; Autophagy

Deferoxamine Preconditioning of Neural-Like Cells Derived from Human Wharton's Jelly Mesenchymal Stem Cells as a Strategy to Promote Their Tolerance and Therapeutic Potential: An In Vitro Study.

Transplantation of neural-like cells is considered as a promising therapeutic strategy developed for neurodegenerative disease in particular for ischemic stroke. Since cell survival is a major concern following cell implantation, a number of studies have underlined the protective effects of preconditioning with hypoxia or hypoxia mimetic pharmacological agents such as deferoxamine (DFO), induced by activation of hypoxia inducible factor-1 (HIF-1) and its target genes. The present study has investigated the effects of DFO preconditioning on some factors involved in cell survival, angiogenesis, and neurogenesis of neural-like cells derived from human Wharton's jelly mesenchymal stem cells (HWJ-MSCs) in presence of hydrogen peroxide (H2O2). HWJ-MSCs were differentiated toward neural-like cells for 14days and neural cell markers were identified using immunocytochemistry. HWJ-MSC-derived neural-like cells were then treated with 100µM DFO, as a known hypoxia mimetic agent for 48h. mRNA and protein expression of HIF-1 target genes including brain-derived neurotrophic factors (BDNF) and vascular endothelial growth factor (VEGF) significantly increased using RT-PCR and Western blotting which were reversed by HIF-1α inhibitor, while, gene expression of Akt-1, Bcl-2, and Bax did not change significantly but pAkt-1 was up-regulated as compared to poor DFO group. However, addition of H2O2 to DFO-treated cells resulted in higher resistance to H2O2-induced cell death. Western blotting analysis also showed significant up-regulation of HIF-1α, BDNF, VEGF, and pAkt-1, and decrease of Bax/Bcl-2 ratio as compared to poor DFO. These results may suggest that DFO preconditioning of HWJ-MSC-derived neural-like cells improves their tolerance and therapeutic potential and might be considered as a valuable strategy to improve cell therapy.