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SPECT Imaging Agents for Detecting Cerebral β-Amyloid Plaques.

Ono M, Saji H - Int J Mol Imaging (2011)

Bottom Line: The development of radiotracers for use in vivo to image β-amyloid (Aβ) plaques in cases of Alzheimer's disease (AD) is an important, active area of research.The presence of Aβ aggregates in the brain is generally accepted as a hallmark of AD.This paper reviews the current situation in the development of agents for SPECT-based imaging of Aβ plaques in Alzheimer's brains.

View Article: PubMed Central - PubMed

Affiliation: Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan.

ABSTRACT
The development of radiotracers for use in vivo to image β-amyloid (Aβ) plaques in cases of Alzheimer's disease (AD) is an important, active area of research. The presence of Aβ aggregates in the brain is generally accepted as a hallmark of AD. Since the only definitive diagnosis of AD is by postmortem staining of affected brain tissue, the development of techniques which enable one to image Aβ plaques in vivo has been strongly desired. Furthermore, the quantitative evaluation of Aβ plaques in the brain could facilitate evaluation of the efficacy of antiamyloid therapies currently under development. This paper reviews the current situation in the development of agents for SPECT-based imaging of Aβ plaques in Alzheimer's brains.

No MeSH data available.


Related in: MedlinePlus

Chemical structure of PET imaging agents tested clinically.
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Related In: Results  -  Collection


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fig2: Chemical structure of PET imaging agents tested clinically.

Mentions: Developing Aβ imaging agents is currently an emerging field of research. The basic requirements for suitable Aβ imaging agents include (i) good penetration of the blood-brain barrier, (ii) selective binding to Aβ plaques, and (iii) clear and contrasting signals between plaques and nonplaques (Figure 1). Based on these requirements, several promising agents with the backbone structure of DDNP, thioflavin-T and Congo Red have been synthesized and evaluated for use in vivo as probes to image Aβ plaques in AD brain. Clinical trials in AD patients have been conducted with several PET imaging agents including [11C]PIB [8–10], [11C]SB-13 [6, 11], [11C]BF-227 [12], [11C]AZD2184 [13], [18F]FDDNP [14–16], [18F]BAY94-9172 [7, 17, 18], [18F] AV-45 [19–21], and [18F]GE-067 [22] (Figure 2), indicating the imaging of Aβ plaques in living brain tissue to be useful for the diagnosis of AD. The 11C-labeled agents limit their use to on-site cyclotrons and sophisticated radiochemistry laboratories due to the short half-life (20 min) of 11C. PET agents with the longer half-life (110 min) radioisotope 18F have recently been developed and could increase the availability of Aβ imaging to all PET facilities, but still represents a minority of modern hospitals, as only a small fraction of hospitals have a PET scanner. Since SPECT is more valuable than PET in terms of routine diagnostic use, the development of more useful Aβ imaging agents for SPECT has been a critical issue. However, progress in developing imaging agents targeting Aβ plaques is less advanced for SPECT than PET. In this review, we summarize the current situation in the development of probes for SPECT-based imaging of Aβ plaques in Alzheimer's brains.


SPECT Imaging Agents for Detecting Cerebral β-Amyloid Plaques.

Ono M, Saji H - Int J Mol Imaging (2011)

Chemical structure of PET imaging agents tested clinically.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3094870&req=5

fig2: Chemical structure of PET imaging agents tested clinically.
Mentions: Developing Aβ imaging agents is currently an emerging field of research. The basic requirements for suitable Aβ imaging agents include (i) good penetration of the blood-brain barrier, (ii) selective binding to Aβ plaques, and (iii) clear and contrasting signals between plaques and nonplaques (Figure 1). Based on these requirements, several promising agents with the backbone structure of DDNP, thioflavin-T and Congo Red have been synthesized and evaluated for use in vivo as probes to image Aβ plaques in AD brain. Clinical trials in AD patients have been conducted with several PET imaging agents including [11C]PIB [8–10], [11C]SB-13 [6, 11], [11C]BF-227 [12], [11C]AZD2184 [13], [18F]FDDNP [14–16], [18F]BAY94-9172 [7, 17, 18], [18F] AV-45 [19–21], and [18F]GE-067 [22] (Figure 2), indicating the imaging of Aβ plaques in living brain tissue to be useful for the diagnosis of AD. The 11C-labeled agents limit their use to on-site cyclotrons and sophisticated radiochemistry laboratories due to the short half-life (20 min) of 11C. PET agents with the longer half-life (110 min) radioisotope 18F have recently been developed and could increase the availability of Aβ imaging to all PET facilities, but still represents a minority of modern hospitals, as only a small fraction of hospitals have a PET scanner. Since SPECT is more valuable than PET in terms of routine diagnostic use, the development of more useful Aβ imaging agents for SPECT has been a critical issue. However, progress in developing imaging agents targeting Aβ plaques is less advanced for SPECT than PET. In this review, we summarize the current situation in the development of probes for SPECT-based imaging of Aβ plaques in Alzheimer's brains.

Bottom Line: The development of radiotracers for use in vivo to image β-amyloid (Aβ) plaques in cases of Alzheimer's disease (AD) is an important, active area of research.The presence of Aβ aggregates in the brain is generally accepted as a hallmark of AD.This paper reviews the current situation in the development of agents for SPECT-based imaging of Aβ plaques in Alzheimer's brains.

View Article: PubMed Central - PubMed

Affiliation: Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan.

ABSTRACT
The development of radiotracers for use in vivo to image β-amyloid (Aβ) plaques in cases of Alzheimer's disease (AD) is an important, active area of research. The presence of Aβ aggregates in the brain is generally accepted as a hallmark of AD. Since the only definitive diagnosis of AD is by postmortem staining of affected brain tissue, the development of techniques which enable one to image Aβ plaques in vivo has been strongly desired. Furthermore, the quantitative evaluation of Aβ plaques in the brain could facilitate evaluation of the efficacy of antiamyloid therapies currently under development. This paper reviews the current situation in the development of agents for SPECT-based imaging of Aβ plaques in Alzheimer's brains.

No MeSH data available.


Related in: MedlinePlus