The protective effect of mindfulness and compassion meditation practices on ageing: Hypotheses,models and experimental implementation

Alzheimer's disease (AD) represents a major health and societal issue; there is no treatment to date and the pathophysiological mechanisms underlying this disease are not well understood. Yet, there is hope that AD risk factors and thus the number of AD cases can be significantly reduced by prevention measures based on lifestyle modifications as targeted by non-pharmacological preventive interventions. So far, these interventions have rarely targeted the psycho-affective risk factors related to depression, stress, anxiety, and feeling of loneliness, which are all prevalent in ageing. This paper presents the hypothesis that the regular practice of mindfulness meditation (MM) and loving-kindness and compassion meditation (LKCM) in the ageing population constitutes a lifestyle that is protective against AD. In this model, these practices can promote cognition, mental health, and well-being by strengthening attention control, metacognitive monitoring, emotion regulation and pro-social capacities. Training these capacities could reduce the risk of AD by upregulating beneficial age-related factors such as cognitive reserve, and down-regulating detrimental age-related factors, such as stress, or depression. As an illustration, we present the Medit-Ageing study (public name Silver Santé Study), an on-going European project that assesses the impact and mechanisms of non-pharmacological interventions including meditation, in the ageing population.     

Risk of seizures and subclinical epileptiform activity in patients with dementia: A systematic review and meta-analysis

BackgroundSeizures and subclinical epileptiform activity are common yet easily overlooked among demented patients. We aimed to investigate their epidemiological characteristics in patients with dementia from various aspects.MethodsWe retrieved relevant observational studies from PubMed and Embase Library until March 2021. Pooled estimate effects were calculated using random-effects models. This study is registered with PROSPERO, number CRD42020200949.ResultsOf the 19144 identified studies, 27 were eligible for inclusion. The pooled period prevalence rates of seizures were 4.86% (95%CI: 3.43–6.51%), 2.68% (95%CI: 2.13–3.28%), 2.81% (95%CI: 2.02–3.71%）and 7.13% (95%CI: 2.67–13.14%) among patients with Alzheimer’s disease (AD), Dementia of Lewy Body (DLB), Frontotemporal dementia (FTD) and Vascular dementia (VaD), respectively. The pooled incidence rate of seizures was [8.4 (95%CI: 4.2–12.7) per 1000 person-years] in AD patients. And the pooled relative risk of seizures in patients with AD was 3.35 (95%CI: 2.69–4.19). Besides, the pooled cumulative incidence rate and prevalence rate of subclinical epileptiform activity among AD patients were [21.41% (95%CI: 0.001–63.60%)] and 9.73% (95%CI: 0.26–28.38%), respectively.ConclusionsThe accurate rates of seizures and subclinical epileptiform activities in the four major dementia types are high. Besides, patients with AD are likely at a higher risk of seizures.     

阿尔茨海默病与雌激素受体α基因多态性的相关性探讨

目的 探讨雌激素受体α基因突变在阿尔茨海默病(AD)发病中的意义。方法 用PCR扩增66例AD患者及143例对照者的激素受体α基因突变点,经限制性内切酶消化后行凝胶电泳确定其基因型。结果 雌激素受体α基因各种基因型频率在患者组与正常对照组之间的差异无显著性。结论 就目前的调查的例数来看,激素受体α基因突变可能不足以构成阿尔茨海默病的独立遗传性危险因子。     

预电针调节胆碱能神经相关蛋白对AD样大鼠学习记忆能力及脑内炎症的影响

目的 观察预电针对AD样大鼠学习记忆能力及脑内炎症的影响.方法 30只SD大鼠分成正常组、模型组、预电针组,每组10只.正常组不做干预,模型组、预电针组每日腹腔注射D半乳糖溶液制备AD样大鼠模型,预电针组另予以针刺百会、足三里穴,接HANS-200A韩式电针仪,连续波,电流1 mA,频率50 Hz,1次/d,20 mi...     

Reducing post-lumbar puncture headaches with small bore atraumatic needles

Lumbar puncture for testing of Alzheimer’s disease pathophysiology for diagnostic confirmation is likely to become more common in the coming years. Minimizing adverse effects from this testing will be essential for clinical practice. Small bore, atraumatic needles reduce the occurrence of post-lumbar puncture headache (PLPH). Our goal was to extend this recommendation specifically to a well-characterized aging population. We assessed PLPH in the Alzheimer’s Disease Neuroimaging Initiative cohort and found that PLPH occurrence was reduced only when using a 24 gauge atraumatic needle. We recommend that lumbar punctures for clinical and research purposes in Alzheimer’s disease be conducted with 24 gauge atraumatic needles.     

Poly(ADP-ribose) polymerase inhibitors in the prevention of neuronal cell death

Poly(ADP-ribose) polymerase is a nucleic enzyme that promotes energy-dependent repair of DNA, thus helping to protect against DNA fragmentation. Overactivation of PARP, for example in the context of apoptosis, may contribute to neuronal cell death. This article briefly reviews claims for PARP inhibitors as agents for the prevention of neuronal cell death, registered in the period 1998 – December 2001. Biological data are sparse in these patents, few claims are backed by in vitro biochemical data and fewer still with in vivo animal model data. The latter have used animal models of ischaemia rather than of neurodegeneration. The place of PARP inhibitors as a clinical therapy to prevent neuronal cell death remains to be determined.     

Solubilization of flurbiprofen into aptamer-modified PEG–PLA micelles for targeted delivery to brain-derived endothelial cells in vitro

Abstract

Novel aptamer-functionalized polyethylene glycol–polylactic acid (PEG–PLA) (APP) micelles were developed with the objective to target the transferrin receptor on brain endothelial cells. Flurbiprofen, a potential drug for therapeutic management of Alzheimer’s disease (AD), was loaded into the APP micelles using the co-solvent evaporation method. Results indicated that 9.03% (w/w) of flurbiprofen was entrapped in APP with good retention capacity in vitro. Targeting potential of APPs was investigated using the transferring receptor-expressing murine brain endothelial bEND5 cell line. APPs significantly enhanced surface association of micelles to bEND5 cells as quantified by fluorescence spectroscopy. Most importantly, APPs significantly enhanced intracellular flurbiprofen delivery when compared to unmodified micelles. These results suggest that APP micelles may offer an effective strategy to deliver therapeutically effective flurbiprofen concentrations into the brain for AD patients.     

Synthesis and bioassay of β-（1,4）-D-mannans as potential agents against Alzheimer＇s disease

Aim： Oligomannurarate 971 derived from a marine plant has shown neuroprotective effects. In this study we synthesized a series of truncated derivatives of the oligosaccharide, and investigated the effect of these derivatives against Aβ peptide toxicity in vitro. Methods： The sulfoxide method was applied to synthesize the derivatives. SH-SY5Y human neuroblastoma cells were treated with Aβ1-40 （2 pmol/L）, and the cell viability was detected using a CCK8 assay. Results： A series of β-（1,4）-D-mannosyl oligosaccharide, ranging from the disaccharide to the hexasaccharide, were synthesized. Addition of 10 pmol/L β-（1,4）-D-mannobiose 6, β-（1,4）-D-mannotriose 9 or β-（1,4）-D-mannotetraose 12 in SH-SY5Y cells significantly attenuated Aβ1-40-induced toxicity. The efficacies were similar to those caused by 10 pmol/L oligomannurarate 971 or alzhemed. Other oligosaccharides including oligomaltoses and oligocelluloses were less active. Conclusion： Synthetic homogeneous short chain β-（1,4）-D-mannans shows neuroprotective effect against Aβ peptide toxicity similar to that of heterogeneous oligomannurarate 971 and alzhemed.     

Huperzine alkaloids from Australasian and southeast Asian Huperzia

Context: The pharmaceutical alkaloid huperzine A (HupA), currently used in herbal supplements and medicines worldwide, is predominantly sourced from the Chinese lycopod Huperzia serrata (Thunb. ex Murray) Trev. (Lycopodiaceae), which on average contains only 0.08?mg HupA g^?1 dry weight, and is experiencing a rapid decline in China due to over-harvesting.

Objective: To find a high-yielding, natural source of HupA and/or the related huperzine B (HupB) that could potentially be used as the starting material in a commercial propagation program.

Materials and methods: We surveyed 17 Huperzia species (15 indigenous to Australia and southeast Asia) for their foliar HupA and HupB concentrations. We also studied intra-specific variation for the huperzines in four species that were available in sufficient numbers, and determined tissue-specific accumulation in larger specimens.

Results: HupA was detected in 11 Australasian and southeast Asian species, with eight also containing HupB, albeit at much lower concentrations. A H. elmeri (Herter) Holub plant from the Philippines had one of the highest HupA concentrations recorded (1.01?mg g^?1 dry wt) and it also had the highest HupB content of all plants surveyed (0.34?mg g^?1 dry wt). Intra-specific HupA and HupB concentrations were extremely variable, and at the intra-plant level, reproductive strobili were found to accumulate the highest HupA concentrations.

Discussion and conclusion: Select Huperzia species from Australia and southeast Asia have potential as the starting material for establishing commercial HupA plantations, but the high intra-specific variability observed suggests that detailed screening is needed to isolate high huperzine-yielding individuals.