Within-person changes in reproductive hormones and cognition in the menopause transition.

OBJECTIVES: Most women complain of cognitive deficits in the menopause transition, though the cause is unclear. The current study investigated the role that within-person changes in reproductive hormones, particularly estradiol, may play in triggering such perimenopausal cognitive difficulties. STUDY DESIGN: Participants were 43 women aged 45-55 years and currently in the menopause transition. Once a week for 12 weeks, participants provided a urine sample for the measurement of estrone glucuronide (E1G), a urinary metabolite of estradiol. Every three weeks across the 12-week period, participants also underwent cognitive testing, including assessments of immediate and delayed memory, attention, and executive function, and completed questionnaires assessing subjective cognitive performance. Potential confounding variables including sleep quality, vasomotor symptoms, and depressive symptoms were also assessed. RESULTS: Within-person E1G was positively associated with objective measures of attention, particularly the ability to passively register auditory information on the first pass, as well as subjective measures of memory, specifically relating to a lower frequency of forgetting things in everyday life. Perimenopausal women with lower estimated levels of intellectual functioning furthermore exhibited a stronger relationship between E1G changes and objective cognitive performance. While depressive mood, poor sleep, and vasomotor symptoms were all negatively associated with at least one aspect of cognitive function, the E1G-cognition relationship was not explained by these factors. CONCLUSIONS: This study provides evidence that validates perimenopausal women's cognitive complaints but also suggests that cognitive deficits are generally mild and transient.

A Neuropsychological Approach to Mild Cognitive Impairment.

OBJECTIVE: A neuropsychological approach to the detection and classification of mild cognitive impairment (MCI) using "gold standard" clinical ratings (CRs) was examined in a sample of independently functioning community dwelling seniors. The relationship between CRs and life satisfaction, concurrent validity of cognitive screening measures, and agreement between CRs and existing criteria for MCI were also determined. METHOD: One hundred and forty-two participants, aged 75 years and older, were administered a comprehensive battery of neuropsychological tests, along with self-report measures of psychological and psychosocial functioning, and functional independence. CRs were based on demographically corrected neuropsychological variables. RESULTS: The prevalence of MCI identified using CRs in this sample was 26.1%. Single and multiple domain subtypes of MCI were readily identified with subtypes reflecting Amnestic and Executive Function impairment predominating. Executive Function was a significant predictor of Life Satisfaction. The MoCA and MMSE both showed weak performance in detecting MCI based on CRs. There was substantial agreement between CRs and the classification criteria for MCI defined by Petersen/Winblad and Jak/Bondi. A global deficit score had near perfect performance as a proxy for CRs in detecting MCI in this sample. CONCLUSIONS: The results provide strong support for the utility of neuropsychological CRs as a "gold standard" operational definition in the detection and classification of MCI in older adults.

Testosterone and depressive symptoms during the late menopause transition.

BACKGROUND: The menopause transition is associated with an increased risk of depression. While the mechanisms behind this increased risk are not well understood, the changing perimenopausal hormonal environment has been hypothesized to play a role. The current study examined the potential influence of testosterone and the ratio of testosterone to estradiol as a potential contributor to depressed mood in the menopause transition. METHODS: Fifty non-depressed perimenopausal women ages 45-55 were recruited for this study. Once every 3 weeks, for a total of four times, the women completed the Centre for Epidemiological Studies-Depression (CES-D) scale for the measurement of depressive symptoms and provided a first-morning urine sample for the measurement of urinary testosterone as well as estrone-3-glucuronide (E1G), a urinary metabolite of estradiol. The week-to-week and mean effects of testosterone, E1G, and the testosterone/E1G ratio on CES-D score were examined. Self-reported sleep quality and vasomotor symptoms were also assessed at each of the four time points. RESULTS: Testosterone levels rose with increasing months since last menstrual period associated with testosterone levels (ß(SE) = 175.3(63.2), p = .006), though this effect was moderated by body mass index (p for the interaction = .001) such that overweight women showed a less pronounced increase over time. Past and current smokers also had higher testosterone levels compared to never smokers. Week-to-week testosterone/E1G ratio was positively associated with CES-D score (ß(SE) = 1.57(0.76), p = .041) but not sleep quality or vasomotor symptoms (ps > .05). Mean testosterone/E1G ratio was also positively associated with vasomotor symptom bother (ß(SE) = 0.14(0.06), p = .018) and poorer sleep quality (ß(SE) = - 0.34(0.09), p = .0001). CONCLUSION: These results suggest that, within the context of the menopause transition, times that are characterized by a higher testosterone-to-estradiol ratio may be associated with higher depressive symptoms. Perimenopausal women with a higher average ratio of testosterone relative to estradiol may also experience more sleep difficulties and vasomotor symptom bother.

Estradiol Fluctuation, Sensitivity to Stress, and Depressive Symptoms in the Menopause Transition: A Pilot Study.

The menopause transition is associated with an increased risk of depressed mood. Preliminary evidence suggests that increased sensitivity to psychosocial stress, triggered by exaggerated perimenopausal estradiol fluctuation, may play a role. However, accurately quantifying estradiol fluctuation while minimizing participant burden has posed a methodological challenge in the field. The current pilot project aimed to test the feasibility of capturing perimenopausal estradiol fluctuation via 12 weekly measurements of estrone-3-glucuronide (E1G), a urinary metabolite of estradiol, using participant-collected urine samples in 15 euthymic perimenopausal women ages 45-55 years. Furthermore, it aimed to correlate E1G fluctuation (standard deviation across the 12 E1G measurements) with weekly mood and cardiovascular, salivary cortisol, and subjective emotional responses to the Trier Social Stress Test (TSST) at weeks 4, 8, and 12. Protocol acceptability and adherence was high; furthermore, E1G fluctuation was positively associated with anhedonic depressive symptoms and weekly negative affect. E1G fluctuation was also associated with increased heart rate throughout the TSST as well as higher levels of rejection, anger, and sadness. E1G fluctuation was not significantly associated with TSST blood pressure or cortisol levels. This study suggests a feasible method of assessing estradiol fluctuation in the menopause transition and provides support for the hypothesis that perimenopausal estradiol fluctuation increases sensitivity to psychosocial stress and vulnerability to depressed mood.

tPA promotes cortical neuron survival via mTOR-dependent mechanisms.

Tissue plasminogen activator (tPA) is a thrombolytic agent commonly used in the treatment of ischemic stroke. While the thrombolytic effects of tPA have been well established, the impact of this blood-brain barrier (BBB) crossing drug on neurons is not known. Given the widespread use of tPA in the clinical setting and the strict therapeutic window established for effective use of the drug, we examined the molecular mechanisms mediating the impact of tPA on postnatal cortical neurons isolated from the mouse brain. Dissociated postnatal primary cortical neurons were treated with tPA and the effects on neuron survival were evaluated. Pharmacological inhibitors of several signaling pathways previously implicated in neuroprotection (mTOR, JAK/STAT, MAPK and PKA-dependent mechanisms) were used to pinpoint the mechanistic effectors of tPA on neuron survival in vitro. We report here that tPA treatment results in a time-dependent neuroprotective effect on postnatal cortical neurons that relies predominantly on Janus kinase (JAK) and mammalian target of rapamycin (mTOR) signaling mechanisms. Taken together, these data suggest that tPA promotes neuroprotection in a temporally-regulated manner and that both JAK and mTOR signaling effectors are critical mediators of this neuroprotective effect. The results suggest the possibility of targeting these defined mechanisms to potentially expand the therapeutic window for tPA.