Unique Responses of Stem Cell-Derived Vascular Endothelial and Mesenchymal Cells to High Levels of Glucose

Diabetes leads to complications in selected organ systems, and vascular endothelial cell (EC) dysfunction and loss is the key initiating and perpetuating step in the development of these complications. Experimental and clinical studies have shown that hyperglycemia leads to EC dysfunction in diabetes. Vascular stem cells that give rise to endothelial progenitor cells (EPCs) and mesenchymal progenitor cells (MPCs) represent an attractive target for cell therapy for diabetic patients. Whether these vascular stem/progenitor cells succumb to the adverse effects of high glucose remains unknown. We sought to determine whether adult vascular stem/progenitor cells display cellular activation and dysfunction upon exposure to high levels of glucose as seen in diabetic complications. Mononuclear cell fraction was prepared from adult blood and bone marrow. EPCs and MPCs were derived, characterized, and exposed to either normal glucose (5 mmol/L) or high glucose levels (25 mmol/L). We then assayed for cell activity and molecular changes following both acute and chronic exposure to high glucose. Our results show that high levels of glucose do not alter the derivation of either EPCs or MPCs. The adult blood-derived EPCs were also resistant to the effects of glucose in terms of growth. Acute exposure to high glucose levels increased caspase-3 activity in EPCs (1.4x increase) and mature ECs (2.3x increase). Interestingly, MPCs showed a transient reduction in growth upon glucose challenge. Our results also show that glucose skews the differentiation of MPCs towards the adipocyte lineage while suppressing other mesenchymal lineages. In summary, our studies show that EPCs are resistant to the effects of high levels of glucose, even following chronic exposure. The findings further show that hyperglycemia may have detrimental effects on the MPCs, causing reduced growth and altering the differentiation potential

In a high-dose melphalan setting, palifermin compared with placebo had no effect on oral mucositis or related patient's burden.

Item does not contain fulltextThis randomized-controlled trial studied the efficacy of palifermin in a chemotherapy-only, high-dose Melphalan (HDM) transplant setting, to reduce oral mucositis (OM) and its sequelae measured by patient-reported outcomes (PRO) and medical resource use. Palifermin, relative to placebo was given either pre-/post-HDM or pre-HDM in patients with multiple myeloma (MM) undergoing auto-SCT at 39 European centers. Oral cavity assessment (WHO) and PRO questionnaires (oral mucositis daily questionnaire (OMDQ) and EQ 5D) were used in 281 patients (mean age 56, +/-s.d.=8 years). 57 patients received placebo. One hundred and fifteen subjects were randomized to pre-/post-HDM receiving palifermin on 3 consecutive days before HDM and after auto-SCT and 109 patients were randomized to pre-HDM, receiving palifermin (60 mug/kg/day) i.v. for 3 consecutive days before HDM. There was no statistically significant difference in maximum OM severity. Severe OM occurred in 37% (placebo), 38% (pre-/post-HDM) and 24% (pre-HDM) of patients. No significant difference was observed with respect to PRO assessments or medical resource use, but more infections and fever during neutropenia were reported in pre-/post-HDM vs placebo (for example, 51 and 26%). To conclude, palifermin was unable to reduce OM or OM-related patient's burden in MM transplant patients.1 juli 201