Combining Human Umbilical Cord Blood Cells With Erythropoietin Enhances Angiogenesis/Neurogenesis and Behavioral Recovery After Stroke

In rats. 

Did your doctor or stroke hospital do anything with this from April 2015?

Erythropoietin Promotes Neural Plasticity and Spatial Memory Recovery in Fimbria-Fornix–Lesioned Rats  April 2015

Are your doctor and stroke hospital being responsible and doing any followup to get research going?

Or will NOTHING BE DONE since everyone in stroke is

waiting for SOMEONE ELSE TO SOLVE THE PROBLEM?

Combining Human Umbilical Cord Blood Cells With Erythropoietin Enhances Angiogenesis/Neurogenesis and Behavioral Recovery After Stroke

Sunyoung Hwang¹, JeeIn Choi² and MinYoung Kim^1,2*

• ¹Rehabilitation and Regeneration Research Center, CHA University, Seongnam, South Korea
• ²Department of Rehabilitation Medicine, CHA Bundang Medical Center, College of Medicine, CHA University, Seongnam, South Korea

Disruption of blood flow in the brain induces stroke, the leading cause of death and disability worldwide. However, so far the therapeutic options are limited. Thus, the therapeutic efficacy of cell-based approaches has been investigated to develop a potential strategy to overcome stroke-induced disability. Human umbilical cord blood cells (hUCBCs) and erythropoietin (EPO) both have angiogenic and neurogenic properties in the injured brain, and their combined administration may exert synergistic effects during neurological recovery following stroke. We investigated the therapeutic potential of hUCBC and EPO combination treatment by comparing its efficacy to those of hUCBC and EPO alone. Adult male Sprague-Dawley rats underwent transient middle cerebral artery occlusion (MCAO). Experimental groups were as follows: saline (injected once with saline 7 d after MCAO); hUCBC (1.2 × 10⁷ total nucleated cells, injected once via the tail vein 7 d after MCAO); EPO (500 IU/kg, injected intraperitoneally for five consecutive days from 7 d after MCAO); and combination of hUCBC and EPO (hUCBC+EPO). Behavioral measures (Modified Neurological Severity Score [mNSS] and cylinder test) were recorded to assess neurological outcomes. Four weeks after MCAO, brains were harvested to analyze the status of neurogenesis and angiogenesis. In vitro assays were also conducted using neural stem and endothelial cells in the oxygen-glucose deprivation condition. Performance on the mNSS and cylinder test showed the most improvement in the hUCBC+EPO group, while hUCBC- and EPO-alone treatments showed superior outcomes relative to the saline group. Neurogenesis and angiogenesis in the cortical region was the most enhanced in the hUCBC+EPO group, while the findings in the hUCBC and EPO treatment alone groups were better than those in the saline group. Astrogliosis in the brain tissue was reduced by hUCBC and EPO treatment. The reduction was largest in the hUCBC+EPO group. These results were consistent with in vitro assessments that showed the strongest neurogenic and angiogenic effect with hUCBC+EPO treatment. This study demonstrates that combination therapy is more effective than single therapy with either hUCBC or EPO for neurological recovery from subacute stroke. The common pathway underlying hUCBC and EPO treatment requires further study.

Introduction

Stroke, caused by the disruption of cerebral blood flow, is a leading cause of death and major disability throughout the world (1). However, the therapeutic options to deal with stroke are limited. Despite efforts to develop new therapies for stroke, all treatments have thus far failed to show a clinical effect or are known to have potential toxic effects. Although intra-arterial thrombolysis and intravenous tissue plasminogen activator therapy have been developed and used for ischemic stroke as effective approaches, those are actually significant only in acute phase with risk of cerebral hemorrhage (1–3). After the onset of stroke, patients experience the greatest amount of neurological recovery during the 3 months post-stroke, which does not last afterwards (4). Before fixation of the impairment in the chronic stage, subacute stroke patients require an effective therapeutic measure, which has remained elusive to date.

While many drugs from successful preclinical experiments have failed in clinical trials for stroke (5), cell therapy has been introduced and expected to be effective by ameliorating neurological impairments due to stroke in vivo with relevant mechanisms identified in vitro (6–8). Although cell-based therapy has therapeutic potential, to date, the greatest limitation must be the lack of clear evidence related to efficacy (9, 10) and safety issues that limit active clinical trials (10).

Human umbilical cord blood cells (hUCBCs) are a rich source of various progenitor cells, including hematopoietic stem cells that can be used as a cell therapy agent and are known to be safe based on 30 years of clinical application (7, 11). The therapeutic efficacy of hUCBC was supported by significant neurological recovery based on modified Neurological Severity Scores (mNSS) for both acute and subacute brain injury (7). Furthermore, evidence on neurogenesis and angiogenesis, in addition to functional recovery, in a stroke model was observed following hUCBC transplantation (12). Our previous clinical study in children with cerebral palsy also revealed functional improvements following hUCBC administration (13).

As a potential approach to enhance the therapeutic potency of cell therapy, combination therapy with a growth factor can be used (14). In this study, erythropoietin (EPO) was selected among the candidate molecules because it has been used clinically as a safe drug. EPO is a member of the hematopoietic cytokine superfamily and has neuroprotective effects against ischemic brain insults (15, 16). Repeated pre-treatment with EPO produced a neuroprotective effect in both focal and global ischemia models (15, 17, 18). Furthermore, EPO enhances angiogenesis and neurogenesis after ischemic stroke, leading to accompanying functional recovery (19–21). Therefore, EPO may be a promising therapeutic agent to enhance hUCBC treatment in ischemic stroke to induce neurogenesis and angiogenesis.

In recovery from stroke, not only neurogenesis, but also coupled angiogenesis, play central roles (22). For example, treatment with human bone marrow stromal cells (hBMSCs) has been found to enhance angiogenesis in the ischemic boundary zone after stroke (23). Moreover, combination treatment with simvastatin, sodium ferulate, and n-butylidenephthalide following hBMSC administration induced neurological improvement with findings of neurogenesis, angiogenesis, and arteriogenesis after cerebral ischemia (24, 25).

Therefore, in this study, we used a well-established rat model of transient ischemia (26) to represent subacute stroke to analyze the therapeutic efficacy of either hUCBC or EPO, and the additive effects of concomitant treatment with both. In addition, we have systematically investigated the underlying mechanism of neurogenesis and angiogenesis not only in in vivo but also in vitro experiments.