PDF(Pubmed)
Abstract：
BACKGROUND: Circadian and homeostatic declines in cognitive performance are observed during the day, most commonly at 14:00. Additionally, postprandial reductions in cognitive ability have been widely demonstrated 1 h after lunch consumption, affecting domains of executive functioning (EF), episodic memory (EM), and attention. Existing evidence shows that anthocyanin-rich foods such as berries may improve or attenuate the decline in EF and EM in ageing adults. Further research is required to assess whether extracts such as wild blueberry extract (WBE) may be beneficial for cognitive function across an acute timeframe, including known periods of reduced functioning.
OBJECTIVE: (1) Study 1: ROAB: To investigate the efficacy of WBE in maintaining EF and EM throughout the day alongside measures of cardiovascular outcomes in healthy older adults. A range of WBE doses were utilised to identify the optimal dose at which cognitive and cardiovascular effects occur. (2) Study 2: BEAT: To replicate alleviation of cognitive decline during a predicted post-lunch dip whilst also improving cardiovascular outcomes following acute WBE 222 mg supplementation.
METHODS: Both studies employed a randomised, double-blind, cross-over, placebo-controlled design to explore the effects of WBE intervention versus placebo on several outcomes, including EM, EF, blood pressure, and heart rate in a healthy older adult population (aged 68-75). In ROAB, 28 participants received a single dose of WBE 111 mg, 222 mg, 444 mg, or 888 mg or placebo over a 5-week period, each separated by a 1-week washout. Outcomes were measured at 0 h, 2 h, 4 h, and 6 h post intervention, with intervention occurring immediately after baseline (0 h). In BEAT, 45 participants received WBE 222 mg and placebo (1-week washout). Outcomes were measured at 0 h and 6 h (14:00) when a post-lunch dip was anticipated. This was further enhanced by consumption of lunch 1 h prior to cognitive testing. The WBE 222 mg intervention aligned with known peaks in plasma blueberry polyphenol metabolites at 2 h post dosing, which would coincide with a predicted drop in post-lunch performance.
RESULTS: ROAB: A significant dip in executive function was apparent at the 4 h timepoint for placebo only, indicating attenuation for WBE doses. Strikingly, WBE 222 mg produced acute reductions in both systolic and diastolic blood pressure compared with placebo. BEAT: EF reaction time was found to be significantly faster for WBE 222 compared to placebo at the predicted post-lunch dip (14:00), with no other notable benefits on a range of cognitive and cardiovascular outcomes.
CONCLUSIONS: These two studies indicate that WBE may have cardiovascular benefits and attenuate the natural cognitive decline observed over the course of the day, particularly when a decline is associated with a circadian rhythm-driven postprandial dip. However, it is important to acknowledge that effects were subtle, and benefits were only observed on a small number of outcomes. Further research is required to explore the utility of WBE in populations already experiencing mild cognitive impairments.
OBJECTIVE: (1) Study 1: ROAB: To investigate the efficacy of WBE in maintaining EF and EM throughout the day alongside measures of cardiovascular outcomes in healthy older adults. A range of WBE doses were utilised to identify the optimal dose at which cognitive and cardiovascular effects occur. (2) Study 2: BEAT: To replicate alleviation of cognitive decline during a predicted post-lunch dip whilst also improving cardiovascular outcomes following acute WBE 222 mg supplementation.
METHODS: Both studies employed a randomised, double-blind, cross-over, placebo-controlled design to explore the effects of WBE intervention versus placebo on several outcomes, including EM, EF, blood pressure, and heart rate in a healthy older adult population (aged 68-75). In ROAB, 28 participants received a single dose of WBE 111 mg, 222 mg, 444 mg, or 888 mg or placebo over a 5-week period, each separated by a 1-week washout. Outcomes were measured at 0 h, 2 h, 4 h, and 6 h post intervention, with intervention occurring immediately after baseline (0 h). In BEAT, 45 participants received WBE 222 mg and placebo (1-week washout). Outcomes were measured at 0 h and 6 h (14:00) when a post-lunch dip was anticipated. This was further enhanced by consumption of lunch 1 h prior to cognitive testing. The WBE 222 mg intervention aligned with known peaks in plasma blueberry polyphenol metabolites at 2 h post dosing, which would coincide with a predicted drop in post-lunch performance.
RESULTS: ROAB: A significant dip in executive function was apparent at the 4 h timepoint for placebo only, indicating attenuation for WBE doses. Strikingly, WBE 222 mg produced acute reductions in both systolic and diastolic blood pressure compared with placebo. BEAT: EF reaction time was found to be significantly faster for WBE 222 compared to placebo at the predicted post-lunch dip (14:00), with no other notable benefits on a range of cognitive and cardiovascular outcomes.
CONCLUSIONS: These two studies indicate that WBE may have cardiovascular benefits and attenuate the natural cognitive decline observed over the course of the day, particularly when a decline is associated with a circadian rhythm-driven postprandial dip. However, it is important to acknowledge that effects were subtle, and benefits were only observed on a small number of outcomes. Further research is required to explore the utility of WBE in populations already experiencing mild cognitive impairments.
摘要：
背景：白天观察到认知表现的昼夜节律和稳态下降，最常见的是14点.此外,餐后认知能力的降低在午餐后1小时被广泛证实，影响执行功能领域(EF)，情景记忆(EM)，和注意。现有证据表明，富含花青素的食物，如浆果，可以改善或减轻老年人EF和EM的下降。需要进一步的研究来评估野生蓝莓提取物（WBE）等提取物是否在急性时间段内对认知功能有益。包括已知的功能减少时期。
目的：（1）研究1：ROAB：研究WBE在健康老年人中全天维持EF和EM以及测量心血管结局的功效。使用一系列WBE剂量来确定发生认知和心血管影响的最佳剂量。（2）研究2：BEAT：在预期的午餐后下降期间复制认知下降的缓解，同时还改善了急性WBE222mg补充后的心血管结果。
方法：两项研究都采用了随机，双盲,cross-over,安慰剂对照设计，以探索WBE干预与安慰剂对几种结果的影响，包括EM，EF,血压,健康的老年人群（68-75岁）的心率。在ROAB,28名参与者接受了单剂量的WBE111毫克，222毫克，444毫克，或在5周内服用888毫克或安慰剂，每个间隔1周冲洗。结果在0h测量，2h,4h,干预后6小时，基线后立即进行干预（0h）。在Beat,45名参与者接受WBE222mg和安慰剂（1周洗脱）。结果是在预期午餐后下降的0小时和6小时(14:00)测量的。在认知测试之前1小时食用午餐进一步增强了这一点。WBE222mg干预与给药后2小时血浆蓝莓多酚代谢物的已知峰值对齐，这将与午餐后表演的预期下降相吻合。
结果：ROAB：仅在安慰剂的4小时时间点，执行功能明显下降，指示WBE剂量的衰减。引人注目的是，与安慰剂相比，WBE222mg可急性降低收缩压和舒张压。BEAT：在预期的午餐后下降（14:00），与安慰剂相比，WBE222的EF反应时间明显更快，对一系列认知和心血管结局没有其他显著益处。
结论：这两项研究表明，WBE可能具有心血管益处，并减轻了一天中观察到的自然认知能力下降，特别是当下降与昼夜节律驱动的餐后下降相关时。然而,重要的是要承认效果是微妙的，仅在少数结局中观察到益处.需要进一步的研究来探索WBE在已经经历轻度认知障碍的人群中的效用。
目的：（1）研究1：ROAB：研究WBE在健康老年人中全天维持EF和EM以及测量心血管结局的功效。使用一系列WBE剂量来确定发生认知和心血管影响的最佳剂量。（2）研究2：BEAT：在预期的午餐后下降期间复制认知下降的缓解，同时还改善了急性WBE222mg补充后的心血管结果。
方法：两项研究都采用了随机，双盲,cross-over,安慰剂对照设计，以探索WBE干预与安慰剂对几种结果的影响，包括EM，EF,血压,健康的老年人群（68-75岁）的心率。在ROAB,28名参与者接受了单剂量的WBE111毫克，222毫克，444毫克，或在5周内服用888毫克或安慰剂，每个间隔1周冲洗。结果在0h测量，2h,4h,干预后6小时，基线后立即进行干预（0h）。在Beat,45名参与者接受WBE222mg和安慰剂（1周洗脱）。结果是在预期午餐后下降的0小时和6小时(14:00)测量的。在认知测试之前1小时食用午餐进一步增强了这一点。WBE222mg干预与给药后2小时血浆蓝莓多酚代谢物的已知峰值对齐，这将与午餐后表演的预期下降相吻合。
结果：ROAB：仅在安慰剂的4小时时间点，执行功能明显下降，指示WBE剂量的衰减。引人注目的是，与安慰剂相比，WBE222mg可急性降低收缩压和舒张压。BEAT：在预期的午餐后下降（14:00），与安慰剂相比，WBE222的EF反应时间明显更快，对一系列认知和心血管结局没有其他显著益处。
结论：这两项研究表明，WBE可能具有心血管益处，并减轻了一天中观察到的自然认知能力下降，特别是当下降与昼夜节律驱动的餐后下降相关时。然而,重要的是要承认效果是微妙的，仅在少数结局中观察到益处.需要进一步的研究来探索WBE在已经经历轻度认知障碍的人群中的效用。
