Cerebrovascular abnormalities in Alzheimer's disease: An adrenergic approach

by Impact Journals LLC

Α1AR-mediated downstream signaling pathway involved in Aβ-induced cerebrovascular abnormalities. Credit: Song Li

Aging-US has published "Involvement of cerebrovascular abnormalities in the pathogenesis and progression of Alzheimer's disease: an adrenergic approach" which reported that alzheimer's disease, as the most common neurodegenerative disease in elder population, is pathologically characterized by β-amyloid plaques, neurofibrillary tangles composed of highly-phosphorylated tau protein and consequently progressive neurodegeneration.

02 nov 2021--Increasing lines of evidence from both clinical and preclinical studies have indicated that age-related cerebrovascular dysfunctions, including the changes in cerebrovascular microstructure, blood-brain barrier integrity, cerebrovascular reactivity and cerebral blood flow, accompany or even precede the development of AD-like pathologies.

In this review, the authors provide an appraisal of the cerebrovascular alterations in AD and the relationship to cognitive impairment and AD pathologies. Moreover, the adrenergic mechanisms leading to cerebrovascular and AD pathologies were further discussed.

Dr. Song Li and Dr. Jun Tan from Chinareport that "Alzheimer's disease (AD) is the most common form of neurodegenerative disease in elder population worldwide."

It is estimated that, by 2060, the number of AD patients in Americans age 65 and older may increase to 13.8 million from 6.2 million today. AD is clinically characterized as cognitive decline and psychiatric manifestations. AD is a progressive neurodegenerative disorder that can start decades before the appearance of clinical symptoms. Although several pathological mechanisms of AD have been identified, the authors believe that no satisfactorily effective therapeutics has been developed. Recently, cerebrovascular dysfunctions, as a possible cause in the development and progression of sporadic AD, have gained increasing attention.

Recent findings further highlighted the prevalence of cerebrovascular disorders in Down syndrome patients and added to a growing body of evidence implicating cerebrovascular abnormalities as a core feature of AD rather than a simple comorbidity.

Moreover, adrenergic system, including /β adrenergic receptors and their downstream molecular signaling process, might serve as the key approach to modulate these cerebrovascular abnormalities and progressive neurodegeneration.

The Li/Tan Research Team concluded that increasing lines of evidence from either preclinical or clinical studies have revealed that the cerebral vascular alterations during early stages of AD may contribute to the pathogenesis and progression of the disease. Cerebral vascular assessment may provide promising tools for AD early diagnosis and cerebral vascular remodeling may yield benefits to AD therapy.

More information: Song Li et al, Involvement of cerebrovascular abnormalities in the pathogenesis and progression of Alzheimer's disease: an adrenergic approach, Aging (2021). DOI: 10.18632/aging.203482

 

Pandemic solitude was positive experience for many

by University of Reading

Credit: Pixabay/CC0 Public Domain

Time spent alone during the pandemic led to positive effects on well-being across all ages, new research has found.

02 nov 2021--The study of more than 2000 teenagers and adults, published in Frontiers in Psychology today, found that most people experienced benefits from solitude during the early days of the global COVID-19 pandemic.

All age groups experienced positive as well as negative effects of being alone. However, the researchers found that descriptions of solitude included more positive effects than negative. On average, well-being scores when participants were alone were 5 out of 7 across all ages, including adolescents aged 13-16.

Some study participants talked about worsening mood or wellbeing, but most described their experiences of solitude in terms of feeling, competent and feeling autonomous. 43% of all respondents mentioned that solitude involved activities and experiences of competence—time spent on skills-building and activities, and that was consistent across all ages. Meanwhile, autonomy—self-connection and reliance on self—was a major feature particularly for adults, who mentioned it twice as often as teenage participants.

Working age adults recorded the most negative experiences with more participants mentioning disrupted well-being (35.6% vs 29.4% in adolescents and 23.7% in older adults) and negative mood (44% vs 27.8% in adolescents and 24.5% in older adults). Experiences of alienation, or the cost of not interacting with friends, were twice as frequent among adolescents (around one in seven, or 14.8%) as when compared to adults (7%) with older adults mentioning it most infrequently (2.3%).

Dr. Netta Weinstein, Associate Professor of Psychology at the University of Reading and lead author of the paper said:

"Our paper shows that aspects of solitude, a positive way of describing being alone, is recognised across all ages as providing benefits for our well-being.

"The conventional wisdom is that adolescents on the whole found that the pandemic was a negative experience, but we see in our study how components of solitude can be positive. Over those first few months of the pandemic here in the UK, we see that working adults were actually the most likely to mention aspects of worsening well-being and mood, but even those are not as commonly mentioned as more positive experiences of solitude.

"We conducted the research in the summer of 2020 which coincided with the end of the first national lockdown in the UK. We know that many people reconnected with hobbies and interests or increasingly appreciating nature on walks and bike rides during that time, and those elements of what we describe as 'self-determined motivation', where we choose to spend time alone for ourselves are seemingly a critical aspect of positive wellbeing.

"Seeing working age adults experience disrupted well-being and negative mood may in fact be related to the pandemic reducing our ability to find peaceful solitude. As we all adjusted to a 'new normal', many working adults found that usual moments of being alone, whether on their commute or during a work break where disrupted. Even for the most ardent of extroverts, these small windows of peace shows the important role of time alone for our mental health. "It also suggests that certain experiences of solitude are learned or valued increasingly with age, having an effect to reduce the impact of negative elements of loneliness and generally boosting well-being. Equally, it suggests that casual inferences about loneliness based on age and stage miss the reality of our nuanced lived experiences."

The results come from a series of in-depth interviews where participants from the UK answered open questions about their experiences of solitude. The team of researchers coded the answers to find shared experiences and measured quantitative data about two aspects of wellbeing associated with solitude, self-determined motivation (the choice to spend time alone) and peaceful mood.

The researchers note that the findings were taken from one phase of the COVID-19 pandemic during the summer of 2020, and recommend that follow up data looks at experiences of solitude during challenging periods such as this one, and also more commonplace periods where daily solitude may look and feel different.

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More information: Netta Weinstein et al, What Time Alone Offers: Narratives of Solitude From Adolescence to Older Adulthood, Frontiers in Psychology (2021). DOI: 10.3389/fpsyg.2021.714518

Provided by University of Reading 

 

Social isolation linked to higher markers of inflammation in older adults

by Wiley

Older US adults who experienced social isolation had higher blood levels of interleukin-6 and C-reactive protein, two markers of inflammation that can have long-term negative consequences for the health of individuals as they age. Credit: Journal of the American Geriatrics Society

In a study published in the Journal of the American Geriatrics Society, older US adults who experienced social isolation had higher blood levels of interleukin-6 and C-reactive protein, two markers of inflammation that can have long-term negative consequences for the health of individuals as they age.

02 nov 2021--The study included a nationally representative sample of 4,648 Medicare beneficiaries aged 65 years and older.

The authors noted that clinical and social interventions that address social isolation among older adults may influence biological processes such as inflammation, as well as their potentially negative effects.

"Our findings demonstrate an important association between social isolation and biological processes. This work is a step in the journey to disentangle the mechanisms by which social isolation leads to higher levels of morbidity and mortality," said lead author Thomas K.M. Cudjoe, MD, MPH, of Johns Hopkins School of Medicine. "My hope is that investigators incorporate objective measures of social isolation and biological markers in future longitudinal studies so that we might continue to advance our understanding of these complex biopsychosocial interactions."

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More information: Thomas K. M. Cudjoe et al, Getting under the skin: Social isolation and biological markers in the National Health and Aging Trends Study, Journal of the American Geriatrics Society (2021). DOI: 10.1111/jgs.17518

 

Increased temperatures contributed to more than 200,000 cases of kidney disease in 15 years in Brazil alone: study

by Monash University

Professor Yuming Guo. Credit: Monash University

Today the world's largest study of the impact of temperature changes and kidney disease reveals that 7.4 percent of all hospitalisations for renal disease can be attributed to an increase in temperature. In Brazil—where the study was focused—this equated to more than 202,000 cases of kidney disease from 2000-2015.

01 nov 2021--The study, led by Professor Yuming Guo and Dr. Shanshan Li, from Planetary Health at Monash University and published in The Lancet Regional Health—Americas journal, for the first time quantifies the risk and attributable burden for hospitalizations of renal diseases related to ambient temperature using daily hospital admission data from 1816 cities in Brazil.

The study comes as the world focuses on the impact of climate change at the COP26 conference in Glasgow from 31 October.

In 2017, a landmark article in The Lancet declared renal diseases a global public health concern, estimating that almost 2.6 million deaths were attributable to impaired kidney function that year. Importantly the incidence of death from kidney disease had risen 26.6 percent compared to a decade previously, an increase that this study may indicate was, in part, caused by climate change.

The study looked at a total of 2,726,886 hospitalizations for renal diseases recorded during the study period. According to Professor Guo, for every 1°C increase in daily mean temperature, there is an almost 1 percent increase in renal disease, with those most impacted being women, children under 4 years of age and those 80+ years of age.

The associations between temperature and renal diseases were largest on the day of the exposure to extreme temperatures but remained for 1–2 days post-exposure.

In the paper the authors—who are also from the University of Sao Paulo—argue that the study "provides robust evidence that more policies should be developed to prevent heat-related hospitalisations and mitigate climate change."

"In the context of global warming, more strategies and policies should be developed to prevent heat-related hospitalizations."

The authors advise interventions should be urgently incorporated into government policy on climate change, including particularly targeting specific individuals, including females, children, adolescents, and the elderly, as they are more vulnerable to heat with regard to renal diseases.

"Moreover, attention should be paid to low- and middle-income countries like Brazil, where reliable heat warning systems and preventive measures are still in need," Professor Guo added.

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More information: Bo Wen et al, Association between Ambient Temperature and Hospitalization for Renal Diseases in Brazil during 2000–2015: A Nationwide Case-Crossover Study, The Lancet Regional Health - Americas (2021). DOI: 10.1016/j.lana.2021.100101