| 1. |
- Ali, Muhammad, et al.
(författare)
-
Leveraging large multi-center cohorts of Alzheimer disease endophenotypes to understand the role of Klotho heterozygosity on disease risk.
- 2022
-
Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 17:5
-
Tidskriftsartikel (refereegranskat)abstract
- Two genetic variants in strong linkage disequilibrium (rs9536314 and rs9527025) in the Klotho (KL) gene, encoding a transmembrane protein, implicated in longevity and associated with brain resilience during normal aging, were recently shown to be associated with Alzheimer disease (AD) risk in cognitively normal participants who are APOE ε4 carriers. Specifically, the participants heterozygous for this variant (KL-SVHET+) showed lower risk of developing AD. Furthermore, a neuroprotective effect of KL-VSHET+ has been suggested against amyloid burden for cognitively normal participants, potentially mediated via the regulation of redox pathways. However, inconsistent associations and a smaller sample size of existing studies pose significant hurdles in drawing definitive conclusions. Here, we performed a well-powered association analysis between KL-VSHET+ and five different AD endophenotypes; brain amyloidosis measured by positron emission tomography (PET) scans (n = 5,541) or cerebrospinal fluid Aβ42 levels (CSF; n = 5,093), as well as biomarkers associated with tau pathology: the CSF Tau (n = 5,127), phosphorylated Tau (pTau181; n = 4,778) and inflammation: CSF soluble triggering receptor expressed on myeloid cells 2 (sTREM2; n = 2,123) levels. Our results found nominally significant associations of KL-VSHET+ status with biomarkers for brain amyloidosis (e.g., CSF Aβ positivity; odds ratio [OR] = 0.67 [95% CI, 0.55-0.78], β = 0.72, p = 0.007) and tau pathology (e.g., biomarker positivity for CSF Tau; OR = 0.39 [95% CI, 0.19-0.77], β = -0.94, p = 0.007, and pTau; OR = 0.50 [95% CI, 0.27-0.96], β = -0.68, p = 0.04) in cognitively normal participants, 60-80 years old, who are APOE e4-carriers. Our work supports previous findings, suggesting that the KL-VSHET+ on an APOE ε4 genotype background may modulate Aβ and tau pathology, thereby lowering the intensity of neurodegeneration and incidence of cognitive decline in older controls susceptible to AD.
|
|
| 2. |
- Deming, Y., et al.
(författare)
-
The MS4A gene cluster is a key modulator of soluble TREM2 and Alzheimer's disease risk
- 2019
-
Ingår i: Science Translational Medicine. - : American Association for the Advancement of Science (AAAS). - 1946-6234 .- 1946-6242. ; 11:505
-
Tidskriftsartikel (refereegranskat)abstract
- Soluble triggering receptor expressed on myeloid cells 2 (sTREM2) in cerebrospinal fluid (CSF) has been associated with Alzheimer's disease (AD). TREM2 plays a critical role in microglial activation, survival, and phagocytosis; however, the pathophysiological role of sTREM2 in AD is not well understood. Understanding the role of sTREM2 in AD may reveal new pathological mechanisms and lead to the identification of therapeutic targets. We performed a genome-wide association study (GWAS) to identify genetic modifiers of CSF sTREM2 obtained from the Alzheimer's Disease Neuroimaging Initiative. Common variants in the membrane-spanning 4-domains subfamily A (MS4A) gene region were associated with CSF sTREM2 concentrations (rs1582763; P = 1.15 x 10(-15)); this was replicated in independent datasets. The variants associated with increased CSF sTREM2 concentrations were associated with reduced AD risk and delayed age at onset of disease. The single-nucleotide polymorphism rs1582763 modified expression of the MS4A4A and MS4A6A genes in multiple tissues, suggesting that one or both of these genes are important for modulating sTREM2 production. Using human macrophages as a proxy for microglia, we found that MS4A4A and TREM2 colocalized on lipid rafts at the plasma membrane, that sTREM2 increased with MS4A4A overexpression, and that silencing of MS4A4A reduced sTREM2 production. These genetic, molecular, and cellular findings suggest that MS4A4A modulates sTREM2. These findings also provide a mechanistic explanation for the original GWAS signal in the MS4A locus for AD risk and indicate that TREM2 may be involved in AD pathogenesis not only in TREM2 risk-variant carriers but also in those with sporadic disease.
|
|
| 3. |
- Funkquist, Anders, 1977-, et al.
(författare)
-
Low CSF/serum ratio of free T4 is associated with decreased quality of life in mild hypothyroidism – A pilot study : CSF/s-T4 associated with QoL in hypothyroidism
- 2020
-
Ingår i: Journal of Clinical and Translational Endocrinology. - Netherlands : Elsevier BV. - 2214-6237. ; 19
-
Tidskriftsartikel (refereegranskat)abstract
- Background & Objective: Patients with mild hypothyroidism often are depressed and have impaired quality of life despite serum free-T4 and T3 within reference values. Therefore, we investigated whether their symptoms were dependent on the concentrations of free -T4 and T3 in the circulation and cerebrospinal fluid (CSF). Methods: Twenty-five newly diagnosed, untreated hypothyroid subjects and as many age- and sex-matched healthy controls were investigated. Blood and CSF sampling was performed in the morning after an overnight fast. Quality of life (QoL) was assessed by a Likert scale. In the hypothyroid subjects, the MADRS rating scale was also used to evaluate symptoms of depression. Furthermore, the results obtained by the questionnaires were related to serum and CSF levels of free- T4 and T3 as well as the ratios between them in CSF and in serum. Results: Self-reported health was considerably lower in hypothyroid subjects. MADRS was considerably higher than the normal range for healthy individuals. Low CSF/serum free-T4 ratio was correlated with an increased depressed state according to MADRS (p < 0.01), and in addition, CSF/serum free-T4 ratio correlated positively with the self-reported general health Likert scale (p < 0.05). Concentrations of TSH, or free-T3 in serum or CSF, were not associated with an increased depressed state or self-reported general health. Conclusions: Low CSF/serum ratio of free-T4 was correlated with impaired general health and mood, in contrast to serum measurements not showing any correlations. These findings might partly explain why some patients with hypothyroidism suffer from mental symptoms, despite adequate serum levels of free-T4. However, the findings need to be confirmed in further and larger studies.
|
|
| 4. |
- Heslegrave, Amanda, et al.
(författare)
-
Increased cerebrospinal fluid soluble TREM2 concentration in Alzheimer's disease.
- 2016
-
Ingår i: Molecular neurodegeneration. - : Springer Science and Business Media LLC. - 1750-1326. ; 11
-
Tidskriftsartikel (refereegranskat)abstract
- The discovery that heterozygous missense mutations in the gene encoding triggering receptor expressed on myeloid cells 2 (TREM2) are risk factors for Alzheimer's disease (AD), with only the apolipoprotein E (APOE) ε4 gene allele conferring a higher risk, has led to increased interest in immune biology in the brain. TREM2 is expressed on microglia, the resident immune cells of the brain and has been linked to phagocytotic clearance of amyloid β (Aβ) plaques. Soluble TREM2 (sTREM2) has previously been measured in cerebrospinal fluid (CSF) by ELISA but in our hands commercial kits have proved unreliable, suggesting that other methods may be required. We developed a mass spectrometry method using selected reaction monitoring for the presence of a TREM2 peptide, which can be used to quantify levels of sTREM2 in CSF.
|
|
| 5. |
- Johansson, Per, et al.
(författare)
-
Cerebrospinal Fluid Biomarkers for Alzheimer's Disease: Diagnostic Performance in a Homogeneous Mono-Center Population
- 2011
-
Ingår i: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 24:3, s. 537-546
-
Tidskriftsartikel (refereegranskat)abstract
- The cerebrospinal fluid (CSF) biomarkers amyloid-beta (A beta)(1-42), T-tau, and P-tau have good diagnostic accuracy for clinically diagnosed Alzheimer's disease (AD). However, in multi-center studies, the predictive values of the CSF biomarkers have been lower, possibly due to differences in procedures for lumbar puncture and CSF handling and storage, and to differences in patient populations, clinical evaluations, and diagnostic procedures. Here we investigate the diagnostic accuracy of CSF biomarkers in a well defined homogeneous mono-center population. We also evaluate an extended panel of amyloid related biomarkers. Sixty consecutive patients admitted for cognitive impairment to a memory clinic were recruited. The participants included patients with AD or mild cognitive impairment (MCI) diagnosed with AD upon follow-up (n = 32), patients with stable MCI (n = 13), patients with other dementias diagnosed at primary evaluation or upon follow-up (n = 15), and healthy controls (n = 20). CSF was analyzed for A beta(1-42), T-tau, P-tau, A beta(X-38), A beta(X-40), A beta(X-42), sA beta PP alpha, and sA beta PP beta. In multivariate analysis, the core biomarkers A beta(1-42), T-tau, and P-tau demonstrated a high ability to diagnose AD versus the combined groups of controls and stable MCI, with an area under the receiver operating characteristic curve (AUROC) of 0.97 (95% CI 0.93-1.00, p < 0.0001). The additional biomarkers only marginally increased AUROC to 0.98 (95% CI 0.95-1.00, p < 0.0001), this increase mainly mediated by A beta(X-42). In conclusion, CSF biomarkers A beta(1-42), T-tau, and P-tau have very high diagnostic accuracy in a well defined cohort of untreated patients, demonstrating the excellent potency of CSF biomarkers to identify pathological processes in AD when a stringent analytical protocol is used.
|
|
| 6. |
|
|
| 7. |
- Johansson, Per, 1966, et al.
(författare)
-
Cerebrospinal fluid substance P concentrations are elevated in patients with Alzheimer's disease.
- 2015
-
Ingår i: Neuroscience letters. - : Elsevier BV. - 1872-7972 .- 0304-3940. ; 609, s. 58-62
-
Tidskriftsartikel (refereegranskat)abstract
- The neuropeptides substance P, orexin A (hypocretin-1) and neurotensin are signaling molecules that influence brain activity. We examined their cerebrospinal fluid (CSF) levels in a study population consisting of Alzheimer's disease (AD) dementia or mild cognitive impairment (MCI) diagnosed with AD dementia upon follow-up (n=32), stable MCI (SMCI, n=13), other dementias (n=15), and healthy controls (n=20). CSF substance P level was increased in AD patients compared to patients with other dementias and healthy controls (P<0.05 and P<0.01, respectively). Patients with other dementia or SMCI had lower CSF orexin A level than AD patients (both P<0.05) and marginally lower level than healthy controls (both P=0.05). CSF neurotensin level was similar in all groups. In the total study population (n=80), CSF substance P level correlated positively with CSF levels of T-tau and P-tau, and in AD patients (n=32), CSF substance P level correlated positively with CSF Aβ1-42 level. In conclusion, CSF substance P level was elevated in AD patients and correlated with CSF Aβ1-42 level, a well established marker of senile plaque pathology. The role of low CSF orexin A level in other dementias or SMCI needs to be explored in further studies.
|
|
| 8. |
- Johansson, Per, 1966, et al.
(författare)
-
Mild dementia is associated with increased adrenal secretion of cortisol and precursor sex steroids in women.
- 2011
-
Ingår i: Clinical endocrinology. - : Wiley. - 1365-2265 .- 0300-0664. ; 75:3, s. 301-308
-
Tidskriftsartikel (refereegranskat)abstract
- Context Sex steroid levels decrease with increasing age, but little is known whether this is of importance for the age-related decline in cognitive function. Design and patients A cross-sectional study of 50 (26 men) consecutive patients under primary evaluation of cognitive impairment (D group) and 18 (9 men) matched healthy controls (C group). Measurements Sex steroid and precursor levels were determined in serum and, when measurable, in cerebrospinal fluid (CSF) using gas chromatography/mass spectroscopy (GC-MS) or liquid chromatography/mass spectroscopy (LC-MS). Sex hormone binding globulin (SHBG) and cortisol concentrations were measured using conventional assays. Results Patients in the D group had higher 24-h urine cortisol levels and increased serum levels of dehydroepiandrosterone (DHEA) and its sulphate ester dihydroepiandrosterone sulphate (DHEAS), androsterone (ADT), and oestrone (E1) and its sulphate ester E1S, compared with the controls. When men and women were analysed separately, increased serum concentrations of E1 and E1S were observed in both D men and D women, whereas increased levels of other sex steroids and cortisol were seen only in D women. Conclusions In both D men and women, serum E1 and E1S levels were increased, whereas other changes were gender specific and only seen in D women. Further studies are needed to determine whether these changes are a cause of, or merely a consequence of, cognitive impairment in elderly subjects.
|
|
| 9. |
- Johansson, Per, 1966, et al.
(författare)
-
Reduced Cerebrospinal Fluid Concentration of Apolipoprotein A-I in Patients with Alzheimer's Disease.
- 2017
-
Ingår i: Journal of Alzheimer's disease : JAD. - 1875-8908 .- 1387-2877. ; 59:3, s. 1017-1026
-
Tidskriftsartikel (refereegranskat)abstract
- Apolipoprotein E (ApoE) has been extensively studied in Alzheimer's disease (AD), but little is known of apolipoprotein A-I (ApoA-I) in cerebrospinal fluid (CSF).Plasma lipids as well as ApoA-I and ApoE in plasma and CSF were determined and related to Mini-Mental State Examination (MMSE) score, APOE genotype, and CSF AD biomarkers.Consecutive patients with AD (n=29), stable mild cognitive impairment (n=13), other dementias (n=14), and healthy controls (n=18) were included at a single center.AD patients had higher plasma triglycerides and lower CSF ApoA-I concentration than controls (both p<0.05). CSF ApoE concentration was reduced in other dementias (p<0.01). In AD as well as other dementias, the ratios between CSF and plasma concentrations of both ApoA-I and ApoE were lower than those in the controls. ApoA-I and ApoE in plasma and CSF were not influenced by APOEɛ4 allele distribution. In the total study population (n=74), CSF ApoA-I correlated positively with MMSE score (r=0.26, p<0.05) and negatively with CSF P-tau (r=-0.25, p<0.05). CSF ApoE correlated positively with CSF concentrations of T-tau and P-tau in the total study population and in AD patients.CSF ApoA-I was reduced in AD patients and associated with measures of cognitive function and AD disease status. The mechanisms underlying the decreased CSF:plasma ratios of ApoA-I and ApoE in AD and other dementias need to be explored in further studies.
|
|
| 10. |
- Johansson, Per, 1966, et al.
(författare)
-
Reduced cerebrospinal fluid concentration of interleukin-12/23 subunit p40 in patients with cognitive impairment.
- 2017
-
Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 12:5
-
Tidskriftsartikel (refereegranskat)abstract
- The role of inflammation in Alzheimer's disease (AD) and other cognitive disorders is unclear. In a well-defined mono-center population, we measured cytokines and chemokines in paired serum and cerebrospinal fluid (CSF) samples.Consecutive patients with AD (n = 30), stable mild cognitive impairment (SMCI, n = 11), other dementias (n = 11), and healthy controls (n = 18) were included. None of the subjects was treated with glucocorticoids, cholinesterase inhibitors, or non-steroidal anti-inflammatory drugs. Serum and CSF concentrations of interleukin-6 (IL-6), IL-8, IL-12/23 p40, IL-15, IL-16, vascular endothelial growth factor-A (VEGF-A), and three chemokines were measured using a multiplex panel.After correction for multiple comparisons, only CSF IL-12/23 p40 concentration differed significantly between the total patient group (n = 52) and controls (n = 18; p = 0.002). Further analyses showed that CSF IL-12/23 p40 concentration was decreased in all patient subgroups (AD, other dementias, and SMCI) compared to healthy controls (p < 0.01, p < 0.05, and p < 0.05, respectively). In the total study population (n = 70), CSF IL-12/23 p40 concentrations correlated positively with CSF concentrations of β-amyloid1-42 (Aβ1-42) and phosphorylated tau protein (P-tau) whereas in AD patients (n = 30), CSF IL-12/23 p40 only correlated positively with CSF P-Tau (r = 0.46, p = 0.01).Most cytokines and chemokines were similar in patients and controls, but CSF IL-12/23 subunit p40 concentration was decreased in patients with cognitive impairment, and correlated with markers of AD disease status. Further studies are needed to evaluate the role of CSF IL-12/23 p40 in other dementias and SMCI.
|
|
