Dy from the same group reported that CY5-SE isoflurane enhanced the small oligomers of Abeta [2]. The Xie study showed that isoflurane induces apoptosis, alters the processing of amyloid precursor protein (APP), and increases the production of Abeta in a human neuroglioma cell line [3]. Because the deposition of Abeta is a key event in the pathogenesis of Alzheimer’s disease (AD), these in vitro findings suggest that isoflurane exposure might worsen the symptoms or accelerate the process of AD. However, Bianchi’s findings [4] suggest otherwise. No decrease in learning and memory and no increase in Abeta deposition following isoflurane exposure were found in 12-monthold Tg2576 transgenic mice. However, the 12-month-old mice may have been too 18334597 old; thus, their learning and memory may havealready been considerably compromised. Many patients in the pre-symptomatic phase of AD are exposed to anesthesia and undergo surgery for different reasons. In the present study, we investigated whether isoflurane exposure during mid-adulthood, which is the pre-symptomatic phase in which Abeta deposition begins, alters the progression of AD. APP/PS1 transgenic mice and their non-transgenic CX-5461 site Wild-type littermates were exposed to isoflurane at 7 months of age, and behavioral changes were tested 48 hours and 5 months later. Finally, the Abeta plaque and oligomer was tested 5 months following the isoflurane exposure.Results Isoflurane Exposure Improved the Short-term Spatial Memory of Both APP/PS1 Transgenic and Wild-type MiceTo evaluate the short-term spatial memory effects of isoflurane on the APP/PS1 transgenic (Tg) and wild-type (Wt) mice, Morris Water Maze(MWM) was performed 48 hours following the isoflurane exposure. As shown in Figure 1A, the reference memory of all animals improved as training progressed. The statistical results indicate that isoflurane had a significant effect on the escapeIsoflurane Attenuates Memory Impairmentlatency (p = 0.023). However, the transgene had no significant effects on the escape latency (p = 0.122). There was no interaction between the isoflurane exposure and the presence of the transgene (p = 0.983). With the UNIANOVA, the latency to find the platform for mice exposed to isoflurane was shorter than in the control mice at day 3, both in the transgenic mice (p = 0.037) and their wild-type littermates (p = 0.035). Similar results were found for the mean pathway (Fig. 1B). Isoflurane exposure significantly affected the pathway (p = 0.024), but the transgene did not (p = 0.853). No interaction between the isoflurane exposure and the presence of the transgene was found (p = 0.950). With the UNIANOVA, the pathway was shorter on day 3 following the isoflurane exposure both in the transgenic mice (p = 0.025) and their wild-type littermates (p = 0.020). The swimming speed was similar among the different groups, and none of the three factors(i.e., isoflurane exposure, transgene or time) affected swimming speed significantly (p.0.150) (Fig. 1C). A probe test was performed on the second day after the final reference memory testing to further test the retention of memory in the mice. The statistical results showed that the isoflurane exposure significantly affected the swimming time in the target quadrant (p = 0.035). However, the presence of the transgene did not significantly affect the swimming time in the target quadrant (p = 0.143). There was no interaction between the two factors (isoflurane and transgene, p.0.397). With the UNIANOVA.Dy from the same group reported that isoflurane enhanced the small oligomers of Abeta [2]. The Xie study showed that isoflurane induces apoptosis, alters the processing of amyloid precursor protein (APP), and increases the production of Abeta in a human neuroglioma cell line [3]. Because the deposition of Abeta is a key event in the pathogenesis of Alzheimer’s disease (AD), these in vitro findings suggest that isoflurane exposure might worsen the symptoms or accelerate the process of AD. However, Bianchi’s findings [4] suggest otherwise. No decrease in learning and memory and no increase in Abeta deposition following isoflurane exposure were found in 12-monthold Tg2576 transgenic mice. However, the 12-month-old mice may have been too 18334597 old; thus, their learning and memory may havealready been considerably compromised. Many patients in the pre-symptomatic phase of AD are exposed to anesthesia and undergo surgery for different reasons. In the present study, we investigated whether isoflurane exposure during mid-adulthood, which is the pre-symptomatic phase in which Abeta deposition begins, alters the progression of AD. APP/PS1 transgenic mice and their non-transgenic wild-type littermates were exposed to isoflurane at 7 months of age, and behavioral changes were tested 48 hours and 5 months later. Finally, the Abeta plaque and oligomer was tested 5 months following the isoflurane exposure.Results Isoflurane Exposure Improved the Short-term Spatial Memory of Both APP/PS1 Transgenic and Wild-type MiceTo evaluate the short-term spatial memory effects of isoflurane on the APP/PS1 transgenic (Tg) and wild-type (Wt) mice, Morris Water Maze(MWM) was performed 48 hours following the isoflurane exposure. As shown in Figure 1A, the reference memory of all animals improved as training progressed. The statistical results indicate that isoflurane had a significant effect on the escapeIsoflurane Attenuates Memory Impairmentlatency (p = 0.023). However, the transgene had no significant effects on the escape latency (p = 0.122). There was no interaction between the isoflurane exposure and the presence of the transgene (p = 0.983). With the UNIANOVA, the latency to find the platform for mice exposed to isoflurane was shorter than in the control mice at day 3, both in the transgenic mice (p = 0.037) and their wild-type littermates (p = 0.035). Similar results were found for the mean pathway (Fig. 1B). Isoflurane exposure significantly affected the pathway (p = 0.024), but the transgene did not (p = 0.853). No interaction between the isoflurane exposure and the presence of the transgene was found (p = 0.950). With the UNIANOVA, the pathway was shorter on day 3 following the isoflurane exposure both in the transgenic mice (p = 0.025) and their wild-type littermates (p = 0.020). The swimming speed was similar among the different groups, and none of the three factors(i.e., isoflurane exposure, transgene or time) affected swimming speed significantly (p.0.150) (Fig. 1C). A probe test was performed on the second day after the final reference memory testing to further test the retention of memory in the mice. The statistical results showed that the isoflurane exposure significantly affected the swimming time in the target quadrant (p = 0.035). However, the presence of the transgene did not significantly affect the swimming time in the target quadrant (p = 0.143). There was no interaction between the two factors (isoflurane and transgene, p.0.397). With the UNIANOVA.
