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Aims While glycemic control is key in effective type 2 diabetes mellitus management, many patients fail to reach their individualized glycemic goal. This analysis aimed to describe a real-world picture of diabetes management: individualized hemoglobin A1c (HbA1c) goals, rate of goal attainment, HbA1c at each line of therapy, and patient awareness of their glycemic goal. Secondly, we aimed to understand physician satisfaction with HbA1c amongst patients aware vs. those unaware of HbA1c goal. Methods Analysis of physicians and the next ten consulting patients with type 2 diabetes mellitus conducted in Europe and the USA including medical record data abstraction/assessment by physicians, a patient-reported survey and a physician survey. Patients were diagnosed for 3 months or more with a known current and target HbA1c. For the sub-analysis assessment of patient awareness of HbA1c goal, in addition to the above, these patients had to have completed a patient-reported questionnaire and answer the question on awareness of HbA1c goal. Results A total of 730 physicians provided data on 8794 patients with type 2 diabetes mellitus; 5331 patients were eligible for this analysis. Overall, mean (standard deviation, SD) individualized HbA1c goal was 6.8% (0.68%). Of eligible patients, 39.1% met their HbA1c goal; of 60.9% of patients not reaching their HbA1c goal, the mean distance from individualized HbA1c goal was 0.9% (SD 1.0%). Physicians progressed patients’ antihyperglycemic therapy when HbA1c was 8% or higher. Among 2560 patients who were included in the sub-analysis assessing the effect of patient awareness of their HbA1c goal on multiple parameters, 70.5% were aware of their HbA1c goal; mean HbA1c goal was 6.8% (0.7%) and current mean HbA1c value 7.1% (1.2%). A total of 949 patients in the sub-analysis (39.2%) achieved their goal; achieving HbA1c goal was not related to knowledge of goal. Patients aware of their HbA1c goal were slightly more adherent to their antihyperglycemic medication. They also were prescribed more antihyperglycemic agents, more often on a later therapy line receiving a GLP-1 receptor agonist, SGLT2i, or insulin, and more often tested their blood glucose levels than patients who were unaware. Physicians were not satisfied with the current blood glucose level of one third of their patients, believing that more of those who were aware of their HbA1c goal could achieve better glucose control (32.4% of aware vs. 28.2% of unaware patients; p = 0.003). Conclusions Our results showed that the proportion of patients with type 2 diabetes mellitus achieving their goals for glycemic control was suboptimal when compared to current guideline criteria, with only about 40% of patients achieving their individualized HbA1c goal. Treatment intensification was often delayed until HbA1c was 8% and higher. Patients aware of their HbA1c goal were slightly more adherent to their antihyperglycemic medication; however, awareness of HbA1c goal did not enhance goal attainment. This highlights the need for a holistic approach to diabetes management, involving patient education, and patient–physician communication and partnership. Supplementary Information The online version contains supplementary material available at 10.1007/s12325-021-01985-3.

Evidence from clinical trials suggest that newer antihyperglycemic agents (AHAs) have a better clinical profile at a higher dose. However, the utilization of the different doses in the real world is not well known. This study aimed to assess the dose utilization of the 2 newer classes of AHAs using the 2018 Adelphi T2DM Disease Specific Programme, a survey involving 730 physicians and 8794 patients in the U.S. and Europe. The analysis included 1612 patients on sodium glucose cotransporter 2 inhibitors (SGLT2i) and 1073 patients on glucagon like peptide-1 receptor agonist (GLP-1RA), either monotherapy or combined therapy. Dose cut points for SGLT2i drugs were based on doses utilized in cardiovascular outcomes trials (at a compound level, Table 1). There is no standard cut point on dosing in GLP-1RA, therefore a conservative approach was applied (see Table for details). Analyses were performed at class level. SGLT2i drugs were more likely to be prescribed at a high dose (85.7%) to patients who were slightly younger than those receiving a lower dose (57.1 vs. 58.9 years). GLP-1RA were prescribed at high dose in 63.2% of the patients. Mean BMI was higher in patients receiving high dose of a GLP-1 receptor agonist. Disclosure D. Lautsch: Employee; Self; Merck & Co., Inc. E. McLeod: Employee; Self; Pfizer Inc. Stock/Shareholder; Self; Pfizer Inc. T. Wang: Employee; Spouse/Partner; Janssen Pharmaceuticals, Inc. Employee; Self; Merck & Co., Inc. C.D. Gonzalez: Employee; Self; Merck & Co., Inc. S. Rajpathak: Employee; Self; Menarini Group. S. Malkani: None. J. Jackson: None. G. Milligan: None. V. Higgins: None. Funding Merck Sharp & Dohme Corp; Pfizer Inc.

Apolipoprotein E (apoE) alleles are important genetic risk factors for Alzheimer's disease (AD), with the ε4 allele increasing and the ε2 allele decreasing risk for developing AD. ApoE has been shown to influence brain amyloid-β peptide (Aβ) and amyloid burden, both in humans and in transgenic mice. Here we show that direct intracerebral administration of lentiviral vectors expressing the three common human apoE isoforms differentially alters hippocampal Aβ and amyloid burden in the PDAPP mouse model of AD. Expression of apoE4 in the absence of mouse apoE increases hippocampal Aβ 1–42 levels and amyloid burden. By contrast, expression of apoE2, even in the presence of mouse apoE, markedly reduces hippocampal Aβ burden. Our data demonstrate rapid apoE isoform-dependent effects on brain Aβ burden in a mouse model of AD. Gene delivery of apoE2 may prevent or reduce brain Aβ burden and the subsequent development of neuritic plaques.

N -Methyl- d -aspartate receptors in the amygdala are known to be crucial for the learning of conditioned fear, although the molecular cascades that N -methyl- d -aspartate receptors regulate are not well understood. Recent experiments from our laboratory have shown that messenger RNA expression of the immediate-early messenger gene, early growth response gene 1, increases in the lateral nucleus of the amygdala following contextual fear conditioning. However, the regulation of the increase in early growth response gene 1 expression is not known. To determine if N -methyl- d -aspartate receptors regulate both fear conditioning and the increase in early growth response gene 1 expression in the lateral nucleus of the amygdala, rats were infused i.c.v. with 2.5 μg of the N -methyl- d -aspartate antagonist, dl -2-amino-5-phosphonovalerate. Most rats were killed 30 min following one-trial contextual fear conditioning and their brains were processed for in situ hybridization detection of early growth response gene 1 messenger RNA expression. The remainder of the rats was tested for retention of fear conditioning 24 h later. In dl -2-amino-5-phosphonovalerate-treated rats, post-shock freezing remained intact, whereas fear-conditioned freezing during the retention test was abolished. Image analysis of early growth response gene 1 messenger RNA revealed that dl -2-amino-5-phosphonovalerate blocked the fear-conditioning-associated increase in early growth response gene 1 expression in the lateral nucleus of the amygdala. In addition, dl -2-amino-5-phosphonovalerate significantly increased early growth response gene 1 expression in the central nucleus of the amygdala. The results reveal differential regulation of early growth response gene 1 messenger RNA in the amygdala by N -methyl- d -aspartate receptors and argue for a functional role of early growth response gene 1 in the formation of long-term memory for contextual fear. Furthermore, the results indicate a functional neuroanatomical circuit within the amygdala that includes dampening of excitatory and activation of inhibitory processes in distinct amygdala nuclei, resulting in the reduction of fear conditioning.

Accumulation of β-amyloid (Aβ) peptides in the cerebral cortex is considered a key event in the pathogenesis of Alzheimer's disease (AD). Presenilin 1 (PS1) plays an essential role in the γ-secretase cleavage of the amyloid precursor protein (APP) and the generation of Aβ peptides. Reduction of Aβ generation via the inhibition of γ-secretase activity, therefore, has been proposed as a therapeutic approach for AD. In this study, we examined whether genetic inactivation of PS1 in postnatal forebrain-restricted conditional knock-out (PS1cKO) mice can prevent the accumulation of Aβ peptides and ameliorate cognitive deficits exhibited by an amyloid mouse model that overexpresses human mutant APP. We found that conditional inactivation of PS1 inAPPtransgenic mice (PS1cKO;APPTg) effectively prevented the accumulation of Aβ peptides and formation of amyloid plaques and inflammatory responses, although it also caused an age-related accumulation of C-terminal fragments of APP. Short-term PS1 inactivation in youngPS1cKO;APPTg mice rescued deficits in contextual fear conditioning and serial spatial reversal learning in a water maze, which were associated withAPPTg mice. Longer-term PS1 inactivation in olderPS1cKO;APPTg mice, however, failed to rescue the contextual memory and hippocampal synaptic deficits and had a decreasing ameliorative effect on the spatial memory impairment. These results reveal thatin vivoreduction of Aβ via the inactivation of PS1 effectively prevents amyloid-associated neuropathological changes and can, but only temporarily, improve cognitive impairments inAPPtransgenic mice.

Studies of gene expression following fear conditioning have demonstrated that the inducible transcription factor, egr-1, is increased in the lateral nucleus of the amygdala shortly following fear conditioning. These studies suggest that egr-1 and its protein product Egr-1 in the amygdala are important for learning and memory of fear. To directly test this hypothesis, an egr-1 antisense oligodeoxynucleotide (antisense-ODN) was injected bilaterally into the amygdala prior to contextual fear conditioning. The antisense-ODN reduced Egr-1 protein in the amygdala and interfered with fear conditioning. A 250-pmole dose produced an 11% decrease in Egr-1 protein and reduced long-term memory of fear as measured by freezing in a retention test 24 h after conditioning, but left shock-induced freezing intact. A larger 500-pmole dose produced a 25% reduction in Egr-1 protein and significantly decreased both freezing immediately following conditioning and freezing in the retention test. A nonsense-ODN had no effect on postshock or retention test freezing. In addition, 500 pmole of antisense-ODN infused prior to the retention test in previously trained rats did not reduce freezing, indicating that antisense-ODN did not suppress conditioned fear behavior. Finally, rats infused with 500 pmole of antisense-ODN displayed unconditioned fear to a predator odor, demonstrating that unconditioned freezing was unaffected by the antisense-ODN. The data indicate that the egr-1 antisense-ODN interferes with learning and memory processes of fear without affecting freezing behavior and suggests that the inducible transcription factor Egr-1 within the amygdala plays important functions in long-term learning and memory of fear.

We have previously shown that apolipoprotein E (Apoe) promotes the formation of amyloid in brain and that astrocyte-specific expression of APOE markedly affects the deposition of amyloid-beta peptides (Abeta) in a mouse model of Alzheimer disease. Given the capacity of astrocytes to degrade Abeta, we investigated the potential role of Apoe in this astrocyte-mediated degradation. In contrast to cultured adult wild-type mouse astrocytes, adult Apoe(-/-) astrocytes do not degrade Abeta present in Abeta plaque-bearing brain sections in vitro. Coincubation with antibodies to either Apoe or Abeta, or with RAP, an antagonist of the low-density lipoprotein receptor family, effectively blocks Abeta degradation by astrocytes. Phase-contrast and confocal microscopy show that Apoe(-/-) astrocytes do not respond to or internalize Abeta deposits to the same extent as do wild-type astrocytes. Thus, Apoe seems to be important in the degradation and clearance of deposited Abeta species by astrocytes, a process that may be impaired in Alzheimer disease.

Expression of the immediate-early gene, NGFI-B (nerve growth factor inducible gene B), was examined in the amygdala, hippocampus, and neocortex following contextual fear conditioning. Rats were either handled, placed within the testing context without receiving the footshock, received a footshock immediately upon placement within the context, or received a footshock after a 3-min delay (delayed-shock). Only the delayed-shock group displayed a fear response (freezing) in the post-shock period and in a retention test 24 h after fear conditioning. Expression of NGFI-B mRNA was increased in the dorsolateral part of the lateral nucleus of the amygdala (LaDL) and the neocortex 30 min following conditioning in the delayed-shock group compared to the other three groups. In addition, following a retention test conducted 24 h after fear conditioning, NGFI-B mRNA expression was increased in the neocortex of the delayed-shock group compared to the handled group. In a subsequent experiment, the effects of pretreatment with the anxiolytic drug, diazepam, on fear conditioning and the concomitant increases in NGFI-B mRNA were investigated. Rats administered a 2.5 mg/kg, i.p. dose of diazepam before fear conditioning did not acquire contextual fear as demonstrated by a lack of freezing in a retention test. Although diazepam blocked fear conditioning while the 40% propylene glycol, 10% ethanol vehicle solution did not, both diazepam and the vehicle reduced the conditioning-induced increase in NGFI-B expression in the LaDL. In contrast, the fear-conditioning-induced NGFI-B increase in the neocortex was blocked by diazepam, but not by the vehicle. The data suggest that the transcriptional factor NGFI-B in the LaDL and neocortex may play a functional role in learning and memory of contextual fear, but blocking the increase in NGFI-B expression in the LaDL is not essential for diazepam to interfere with fear conditioning.

Although the amygdala is known to be crucial for fear conditioning, little is known about the molecular and cellular mechanisms in the amygdala that are important for fear conditioning. One possible mechanism may be the activation of immediate-early genes, which function as regulatory factors of transcriptional processes. To investigate whether one of the major immediate-early gene families is involved in the learning and memory of fear, we examined the effects of fear conditioning on the expression of the four members of the early growth response (EGR) gene family, EGR-1, EGR-2, EGR-3, and EGR-4. Image analysis of in situ hybridization of messenger RNA of the four family members was performed in the amygdala, hippocampus, and neocortex 15, 30 and 60 min following one-trial contextual fear conditioning. Rats were either handled, placed within the testing context without receiving the footshock, and received a footshock immediately upon placement within the context, or received a footshock after a 3-min delay (delayed-shock). Of the four groups, only the delayed-shock group exhibited a fear response (freezing). EGR-1 messenger RNA expression in the dorsolateral part of the lateral amygdaloid nucleus was significantly greater in the delayed-shock group compared with the other groups 15 and 30 min following the conditioning. The increased expression of EGR-1 was specifically localized to the lateral nucleus of the amygdala; expression in the hippocampus and cortex was not increased by fear conditioning. In contrast, the expression of EGR-2, EGR-3, and EGR-4 messenger RNA was not increased in the amygdala, hippocampus or cortex following fear conditioning. In addition, following a retention test conducted 24 h after fear conditioning, no increases were found in the expression of EGR-1 messenger RNA expression in the amygdala, hippocampus or cortex. The results demonstrate that of the four genes of the EGR family of transcription-regulatory factors, only EGR-1 messenger RNA in the dorsolateral portion of the lateral nucleus of the amygdala was specifically increased with contextual fear conditioning. It is suggested that EGR-1 plays a functional role during learning, but not retrieval, of contextual fear within the lateral nucleus of the amygdala.

Publisher Summary This chapter discusses the neurobehavioral system approach in rats to study the molecular biology of fear. The chapter presents three examples of a neurobehavioral system approach to the study of gene expression in contextual fear conditioning, innate fear of a predator odor, and exaggerated contextually conditioned fear. All of the examples use a species-specific, ethologically-relevant fear response: freezing. As fear-related freezing is dependent on the lateral, basolateral and central nucleus of the amygdala, the neurobehavioral systems approach compels to investigate molecular changes in these nuclei to find the molecular basis of fear. The chapter explores that this approach has yielded important differences in gene expression between fear conditioning and innate fear. The chapter emphasizes that implementation and augmentation of neurobehavioral strategies should produce more insights into the basic neurobiology of conditioned and innate fear, and have important implications for the neurobiology of anxiety disorders.

Mutations in presenilins are the major cause of familial Alzheimer's disease, but the pathogenic mechanism by which presenilin mutations cause memory loss and neurodegeneration remains unclear. Here we demonstrate that conditional double knockout mice lacking both presenilins in the postnatal forebrain exhibit impairments in hippocampal memory and synaptic plasticity. These deficits are associated with specific reductions in NMDA receptor-mediated responses and synaptic levels of NMDA receptors and αCaMKII. Furthermore, loss of presenilins causes reduced expression of CBP and CREB/CBP target genes, such as c-fos and BDNF. With increasing age, mutant mice develop striking neurodegeneration of the cerebral cortex and worsening impairments of memory and synaptic function. Neurodegeneration is accompanied by increased levels of the Cdk5 activator p25 and hyperphosphorylated tau. These results define essential roles and molecular targets of presenilins in synaptic plasticity, learning and memory, and neuronal survival in the adult cerebral cortex.