Pavagada Sivasankara Mathuranath

Background: The southern India state of Kerala has among the highest proportion of older adults in its population in the country. An increase in chronic age-related diseases such as dementia is expected in the older Kerala population. Identifying older individuals early in the course of cognitive decline offers the best hope of introducing preventive measures early and planning management. However, the epidemiology and pathogenesis of predementia syndromes at the early stages of cognitive decline in older adults are not well established in India. Objective: The Kerala Einstein Study (KES) is a community-based cohort study that was established in 2008 and is based in the Kozhikode district in Kerala state. KES aims to establish risk factors and brain substrates of motoric cognitive risk syndrome (MCR), a predementia syndrome characterized by the presence of slow gait and subjective cognitive concerns in individuals without dementia or disability. This protocol describes the study design and procedures for this KES project. Methods: KES is proposing to enroll a sample of 1000 adults ≥60 years old from urban and rural areas in the Kozhikode district of Kerala state: 200 recruited in the previous phase of KES and 800 new participants to be recruited in this project. MCR is the cognitive phenotype of primary interest. The associations between previously established risk factors for dementia as well as novel risk factors (apathy and traumatic brain injury) and MCR will be examined in KES. Risk factor profiles for MCR will be compared between urban and rural residents as well as with individuals who meet the criteria for mild cognitive impairment (MCI). Cognitive and physical function, medical history and medications, sociodemographic characteristics, lifestyle patterns, and activities of daily living will be evaluated. Participants will also undergo magnetic resonance imaging and electrocardiogram investigations. Longitudinal follow-up is planned in a subset of participants as a prelude to future longitudinal studies. Results: KES (2R01AG039330-07) was funded by the US National Institutes of Health in September 2019 and received approval from the Indian Medical Council of Research to start the study in June 2021. We had recruited 433 new participants from urban and rural sites in Kozhikode as of May 2023: 41.1% (178/433) women, 67.7% (293/433) rural residents, and 13.4% (58/433) MCR cases. Enrollment is actively ongoing at all the KES recruitment sites. Conclusions: KES will provide new insights into risk factors and brain substrates associated with MCR in India and will help guide future development of regionally specific preventive interventions for dementia. International Registered Report Identifier (IRRID): DERR1-10.2196/49933

Journal of Medical Internet Research - International Scientific Journal for Medical Research, Information and Communication on the Internet #Preprint #PeerReviewMe: Warning: This is a unreviewed preprint. Readers are warned that the document has not been peer-reviewed by expert/patient reviewers or an academic editor, may contain misleading claims, and is likely to undergo changes before final publication, if accepted, or may have been rejected/withdrawn. Readers with interest and expertise are encouraged to sign up as peer-reviewer, if the paper is within an open peer-review period. Please cite this preprint only for review purposes or for grant applications and CVs (if you are the author). Background: The southern India state of Kerala has among the highest proportion of older adults in its population in the country. An increase in chronic age-related diseases such as dementia is expected in the older Kerala population. Identifying older individuals early in the course of cognitive decline offers the best hope of introducing preventive measures early and planning management. However, the epidemiology and pathogenesis of predementia syndromes at the early stages of cognitive decline in older adults are not well established in India. Objective: The Kerala Einstein Study (KES) is a community-based cohort study that was established in 2008 and is based in the Kozhikode district in Kerala state. KES aims to establish risk factors and brain substrates of motoric cognitive risk syndrome (MCR), a predementia syndrome characterized by the presence of slow gait and subjective cognitive concerns in individuals without dementia or disability. This protocol describes the study design and procedures for this KES project. Methods: KES is proposing to enroll a sample of 1000 adults ≥60 years old from urban and rural areas in the Kozhikode district of Kerala state: 200 recruited in the previous phase of KES and 800 new participants to be recruited in this project. MCR is the cognitive phenotype of primary interest. The associations between previously established risk factors for dementia as well as novel risk factors (apathy and traumatic brain injury) and MCR will be examined in KES. Risk factor profiles for MCR will be compared between urban and rural residents as well as with individuals who meet the criteria for mild cognitive impairment (MCI). Cognitive and physical function, medical history and medications, sociodemographic characteristics, lifestyle patterns, and activities of daily living will be evaluated. Participants will also undergo magnetic resonance imaging and electrocardiogram investigations. Longitudinal follow-up is planned in a subset of participants as a prelude to future longitudinal studies. Results: KES (2R01AG039330-07) was funded by the US National Institutes of Health in September 2019 and received approval from the Indian Medical Council of Research to start the study in June 2021. We had recruited 433 new participants from urban and rural sites in Kozhikode as of May 2023: 41.1% (178/433) women, 67.7% (293/433) rural residents, and 13.4% (58/433) MCR cases. Enrollment is actively ongoing at all the KES recruitment sites. Conclusions: KES will provide new insights into risk factors and brain substrates associated with MCR in India and will help guide future development of regionally specific preventive interventions for dementia.

Background Disorders of tetrahydrobiopterin metabolism represent a rare group of inherited neurotransmitter disorders that manifests mainly in infancy or childhood with developmental delay, neuroregression, epilepsy, movement disorders, and autonomic symptoms. Methodology A retrospective review of genetically confirmed cases of disorders of tetrahydrobiopterin metabolism over a period of three years (Jan 2018 to Jan 2021) was performed across two paediatric neurology centres from South India. Results A total of nine patients(M:F=4:5) fulfilled the eligibility criteria. The genetic variants detected include homozygous mutations in the QDPR(n=6), GCH1(n=2), and PTS(n=1) genes. The median age at onset of symptoms was 6-months(range 3-78 months), while that at diagnosis was 15-months (8-120 months), resulting in a median delay in diagnosis of 9-months. The main clinical manifestations included neuroregression (89%), developmental delay(78%), dystonia(78%) and seizures(55%). Management strategies included a phenylalanine restricted diet, levodopa/carbidopa, 5-Hydroxytryphtophan, and folinic acid. Only, Patient-2 afforded and received BH4 supplementation at a sub-optimal dose later in the disease course. We had a median duration of follow up of 15 months (range 2-48 months). Though the biochemical response has been marked; except for patients with GTPCH deficiency, only mild clinical improvement was noted with regards to developmental milestones, seizures, or dystonia in others. Conclusion Tetrahydrobiopterin deficiencies represent a rare yet potentially treatable cause for non-phenylketonuria hyperphenylalaninemia with better outcomes when treated early in life. Screening for disorders of biopterin metabolism in patients with hyperphenylalaninemia prevents delayed diagnosis. This study expands the genotype-phenotype spectrum of patients with disorders of tetrahydrobiopterin metabolism from South India.

INTRODUCTION: Defective immune cell-mediated clearance of amyloid-beta (Aβ) and Aβ-associated inflammatory activation of immune cells are key contributors of Aβ accumulation and neurodegeneration in Alzheimer’s disease (AD), however, the underlying mechanisms remain elusive. METHODS: Differentiated THP-1 cells treated with Aβ and AD patient-derived macrophages were used as in-vitro model. The role of SHARPIN was analysed in differentiated THP-1 cells using siRNA-mediated knockdown followed by immunoblotting, ELISA, real-time PCR, immunoprecipitation and flow cytometry. Differentiated SHSY5Y cells were used to study inflammation-mediated apoptosis. RESULTS: SHARPIN was found to regulate Aβ-phagocytosis and NLRP3 expression in THP-1 derived macrophages. Further, it was found to promote macrophage polarization to an M1 (pro-inflammatory) phenotype resulting in enhanced inflammation and associated neuronal death, demonstrated using in-vitro culture systems. SHARPIN expression by blood-derived macrophages was further found to be higher in the early stages of AD, which correlates with Aβ _40/42 concentration in the plasma and age of the study subjects. DISCUSSION: The novel protein, SHARPIN has been shown to play critical roles in regulation of Aβ-phagocytosis and inflammation in AD and the mechanism by which SHARPIN is activated by Aβ in macrophages has been elucidated.

Neuroanatomical correlates of apathy and disinhibition, behavioral abnormalities in behavioral variant Frontotemporal dementia (bvFTD) remain unclear. In this study 45 participants (25 bvFTD patients and 20 controls) provided data on clinical, neuropsychological, behavioral (on Frontal Systems Behavior (FrSBe) Scale), cortical volume (on voxel-based morphometry (VBM)) and tract based spatial fractional anisotropy ((FA) on magnetic resonance imaging (MRI), allowing examination of the neural correlates of apathy and disinhibition. The patients with bvFTD had predominant grey matter loss and corresponding white matter fractional anisotropy reduction in the frontal and temporal lobe compared to the controls. Grey matter loss in frontal, temporal and limbic structures correlated with apathy and degeneration in temporal limbic brain areas correlated with disinhibition. FA changes in inferior fronto-occipital fasciculus and forceps minor correlated with apathy and fibre integrity changes in the superior longitudinal fasciculus correlated with disinhibition. The current study suggests that apathy and disinhibition arises due to changes in the frontal, temporal and limbic brain areas in bvFTD.

BACKGROUND AND PURPOSE: Brain iron deposition has been implicated as a major culprit in the pathophysiology of neurodegeneration. However, the quantitative assessment of iron in behavioral variant frontotemporal dementia and primary progressive aphasia brains has not been performed, to our knowledge. The aim of our study was to investigate the characteristic iron levels in the frontotemporal dementia subtypes using susceptibility-weighted imaging and report its association with behavioral profiles. MATERIALS AND METHODS: This prospective study included 46 patients with frontotemporal dementia (34 with behavioral variant frontotemporal dementia and 12 with primary progressive aphasia) and 34 age-matched healthy controls. We performed behavioral and neuropsychological assessment in all the subjects. The quantitative iron load was determined on SWI in the superior frontal gyrus and temporal pole, precentral gyrus, basal ganglia, anterior cingulate, frontal white matter, head and body of the hippocampus, red nucleus, substantia nigra, insula, and dentate nucleus. A linear regression analysis was performed to correlate iron content and behavioral scores in patients. RESULTS: The iron content of the bilateral superior frontal and temporal gyri, anterior cingulate, putamen, right hemispheric precentral gyrus, insula, hippocampus, and red nucleus was higher in patients with behavioral variant frontotemporal dementia than in controls. Patients with primary progressive aphasia had increased iron levels in the left superior temporal gyrus. In addition, right superior frontal gyrus iron deposition discriminated behavioral variant frontotemporal dementia from primary progressive aphasia. A strong positive association was found between apathy and iron content in the superior frontal gyrus and disinhibition and iron content in the putamen. CONCLUSIONS: Quantitative assessment of iron deposition with SWI may serve as a new biomarker in the diagnostic work-up of frontotemporal dementia and help distinguish frontotemporal dementia subtypes.

Background: This study delineates the role of the interaction of apolipoprotein E (APOE) and MAPT alleles in contributing to disease risks of dementia in a southern Indian population. Methods: A sample of 419 patients comprising Alzheimer's disease (AD; n = 156), mild cognitive impairment (MCI; n = 87), frontotemporal dementia (FTD; n = 127), vascular dementia (VD; n = 37), and dementia with Lewy bodies (DLB; n = 12) was analysed in comparison with a control group (n = 138). APOE genotyping and MAPT haplotyping were performed on all study subjects. Results: Multivariate logistic regression analysis showed that variability on the APOE locus influenced the relative risk of dementia in the study population. The APOE ε4 allele increased the disease risk most significantly for AD (OR = 3.468, p < 0.0001) and MCI (OR = 2.901, p < 0.0001). The APOE ε2 allele remained protective for AD (OR = 0.205, p < 0.05). For FTD, VD, and DLB, the APOE ε4 allele was ineffectual in modulating disease risk. The MAPT H1 haplotype was not an overrepresented marker of neurodegenerative diseases. The H1H1 genotype had an additive effect in contributing to either disease risk in combination with the APOE ε4 allele or protection in combination with the APOE ε2 or ε3 allele. Conclusions: This study is a reappraisal of the strong association of APOE variability with AD in southern India when compared to other dementia groups, while the transcriptional differences between MAPT haplotypes have a limited role in Indian dementia patients.