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Stroke and head trauma are worldwide public health problems and leading causes of death and disability in humans, yet, no adequate neuroprotective treatment is available for therapy. Glutamate antagonists are considered major drug candidates for neuroprotection in stroke and trauma. However, N-methyl-D-aspartate antagonists failed clinical trials because of unacceptable side effects and short therapeutic time window. ␣-Amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) antagonists derived from the quinoxalinedione scaffold cannot be used in humans because of their insolubility and resulting renal toxicity. Therefore, achieving water solubility of quinoxalinediones without loss of selectivity and potency profiles becomes a major challenge for medicinal chemistry. One of the major tenets in the chemistry of glutamate antagonists is that the incorporation of phosphonate into the glutamate framework results in preferential N-methyl-D-aspartate antagonism. Therefore, synthesis of phosphonate derivatives of quinoxalinediones was not pursued because of a predicted loss of their selectivity toward AMPA. Here, we report that introduction of a methylphosphonate group into the quinoxalinedione skeleton leaves potency as AMPA antagonists and selectivity for the AMPA receptor unchanged and dramatically improves solubility. One such novel phosphonate quinoxalinedione derivative and competitive AMPA antagonist ZK200775 exhibited a surprisingly long therapeutic time window of >4 h after permanent occlusion of the middle cerebral artery in rats and was devoid of renal toxicity. Furthermore, delayed treatment with ZK200775 commencing 2 h after onset of reperfusion in transient middle cerebral artery occlusion resulted in a dramatic reduction of the infarct size. ZK200775 alleviated also both cortical and hippocampal damage induced by head trauma in the rat. These observations suggest that phosphonate quinoxalinedione-based AMPA antagonists may offer new prospects for treatment of stroke and trauma in humans.

OBJECTIVETo assess the validity of self-report measures of diabetes medication adherence and evaluate the effect of depression on the validity of these reports.RESEARCH DESIGN AND METHODSAdults with type 2 diabetes, treated with oral medications, completed a set of medication adherence self-reports that varied response scales and time frames, were administered structured clinical interviews for depression, and provided blood samples for HbA1c as part of a screening for an intervention study. A subsample of participants with HbA1c ≥7.0% and clinically significant depression received Medication Event Monitoring System (MEMS) bottle caps to record adherence. Analyses examined relationships between adherence measures and HbA1c and, in the subsample, MEMS. Moderated linear regression evaluated whether depression severity modified relationships with HbA1c.RESULTSParticipant (n = 170, 57% men, 81% white, mean HbA1c 8.3% [SD, 1.7]) adherence self-reports were significantly (r = −0.18 to −0.28; P < 0.03) associated with lower HbA1c. In the subsample (n = 88), all self-reports were significantly (r = 0.35 to 0.55; P ≤ 0.001) associated with MEMS-measured adherence. Depression significantly moderated the relationship between three of six self-reports and HbA1c; at high levels of depression, associations with HbA1c became nonsignificant.CONCLUSIONSResults support the validity of easily administered self-reports for diabetes medication adherence. One-month, percentage-based ratings of adherence had the strongest associations with MEMS and HbA1c; those requiring the report of missed doses had weaker associations. One-week self-ratings and measures that require respondents to record the number of missed doses appear to be vulnerable to bias from depression severity.

Despite the fact that epithelial oBRB and endothelial BBB have developed as separate entities with many site-specific functions, their transport and permeation characteristics display surprising similarities, that include the polarized expression of the two major efflux pumps P-gp and MRP.