Amyloid-β Dependent Microgliosis Occurs Through Src Kinase Activation in Alzheimer\u27s Disease

The major histopathologic hallmark of Alzheimer’s disease (AD) is the presence of (3-amyloid plaques that are often associated with reactive microglia in the brain. It has been suggested modulating the microglial phenotype to attenuate an inflammatory response may prove to be useful in determining therapies for prevention or delay of the disease. My dissertation supports he hypothesis that Ap stimulates microglial activation through a specific tyrosine kinase-dependent response involving the Src kinase family. Using primary mouse microglia we observed that both fibrillar and oligomeric Ap stimulated increased microglial protein phosphotyrosine levels including active levels of the kinase Src and a subsequent increase in secretion of the cytokine, tumor necrosis factor alpha (TNFa). This response was attenuated by using a Abl/Src family kinase inhibitor, dasatinib. Intracerebroventricular infusions of AP oligomer into C57BL/6 adult mice elevated hippocampal phosphotyrosine levels and microgliosis that were attenuate by dasatinib treatment. To evaluate the efficiency of dasatinib in a relevant transgenic model of AD, drug was subcutaneously infused into 13-month old APP/PS1 transgenic mice. Behavioral testing using T-maze showed better performance from dasatinib infused mice as compared to vehicle treated and control animals. Biochemical analyses demonstrated that dasatinib infused animals had lower total protein phosphotyrosine and pSrc levels in the hippocampus. Dasatinib is an FDA approved drug for treating chronic myeloid leukemia and can cross the blood brain barrier. Our demonstration of the microglial inhibitory action of this drug defines a novel use. Based upon the observation that AD brains showed increase in active, phosphorylated Lyn levels in reactive microglia, this kinase may also represent a possible microglial inhibitory target as well. Following a high throughput screening kinase assay, four drugs were identified. One compound LDDN-0003499 inhibited total protein phosphotyrosine as well as active pLyn levels in BV2 microglial cell line. LPS stimulated microglia treated with LDDN-0003499 demonstrated attenuation of TNF-a levels secretion. Collectively, our data supports the idea that non-receptor tyrosine kinase inhibition could be an important therapeutic goal for prevention and/or delay of AD

Between Two Worlds within India: Exploring Factors Influencing Antenatal Care Access in Odisha and Maharashtra

Background and objective: India’s maternal mortality ratio continues to show a steady decline; however, more attention and resources need to be directed towards improving equitable utilization of and access to essential maternal health services across the states. Disparities are particularly acute in Empowered Action Group (EAG) states like Odisha, which exhibit the lowest health performance indicators and contribute significantly to the country’s health burden. In contrast, non-EAG states such as Maharashtra report better health outcomes. This study aims to explore the factors influencing the utilization of four or more antenatal care (ANC) visits during pregnancy in Odisha and Maharashtra. By examining the role of these factors in adherence to WHO-recommended ANC practices to improve maternal health, we seek to gain a better understanding of the disparities in maternal mortality ratio (MMR) between these two states. Methods: The study uses the most recent 2019-2021 India’s National Family Health Survey (NFHS-5) dataset to analyze data collected from ever-married women aged 15-49 years. Using the Anderson-Newman behavioral model for healthcare utilization, we identified potential predictors to test association with four or more ANC visits during pregnancy. We conducted bivariate analysis and ran regression models to examine the factors affecting ≥4 ANC visits in Odisha and Maharashtra. Results: While distance from health facilities was significantly linked to lower utilization of ≥4 ANCs in both states, factors such as place of residence, health insurance coverage, and desiredness of child were not significant predictors in either state. In Odisha, poor socioeconomic status, lack of healthcare-seeking permission, and high parity births were negatively associated with ≥4 ANC utilization, unlike in Maharashtra. Additionally, women with secondary education or higher and those of Hindu religion were not significantly more likely to utilize ≥4 ANCs in Odisha, while in Maharashtra, they were significantly more inclined to do so. Conclusion: The findings underscore notable differences in maternal health service utilization across Indian states. Although Odisha shows a higher level of ANC use than Maharashtra, Odisha’s persistently higher MMR than Maharashtra may be partly explained by considerable inequities in ANC use across socioeconomic status, empowerment levels for care-seeking, and high-risk pregnancies. Targeted interventions addressing these factors are imperative to bridge the existing gaps and ensure equitable access to quality maternal healthcare services for all women, further reducing maternal mortality in India.Master of Public Healt

Beta amyloid oligomers and fibrils stimulate differential activation of primary microglia

<p>Abstract</p> <p>Background</p> <p>Beta amyloid (Aβ) peptides are the major constituents of the senile plaques present in Alzheimer's diseased brain. Pathogenesis has been associated with the aggregated form of the peptide as these fibrils are the conformation readily found in the plaques. However, recent studies have shown that the nonaggregated, soluble assemblies of Aβ have the potential to stimulate neuronal dysfunction and may play a prominent role in the pathogenesis of Alzheimer's disease.</p> <p>Methods</p> <p>Soluble, synthetic Aβ1–42 oligomers were prepared producing mainly dimer-trimer conformations as assessed by SDS-PAGE. Similar analysis demonstrated fibril preparations to produce large insoluble aggregates unable to migrate out of the stacking portion of the gels. These peptide preparations were used to stimulate primary murine microglia and cortical neuron cultures. Microglia were analyzed for changes in signaling response and secretory phenotype via Western analysis and ELISA. Viability was examined by quantifying lactate dehydrogenase release from the cultures.</p> <p>Results</p> <p>Aβ oligomers and fibrils were used to stimulate microglia for comparison. Both the oligomers and fibrils stimulated proinflammatory activation of primary microglia but the specific conformation of the peptide determined the activation profile. Oligomers stimulated increased levels of active, phosphorylated Lyn and Syk kinase as well as p38 MAP kinase compared to fibrils. Moreover, oligomers stimulated a differential secretory profile for interleukin 6, monocyte chemoattractant protein-1 and keratinocyte chemoattractant when compared to fibrils. Finally, soluble oligomers stimulated death of cultured cortical neurons that was exacerbated by the presence of microglia.</p> <p>Conclusion</p> <p>These data suggest that fibrils and oligomers stimulate unique signaling responses in microglia leading to discrete secretory changes and effects on neuron survival. This suggests that inflammation changes during disease may be the consequence of unique peptide-stimulated events and each conformation may represent an individual anti-inflammatory therapeutic target.</p

A multi-targeted approach to suppress tumor-promoting inflammation

Cancers harbor significant genetic heterogeneity and patterns of relapse following many therapies are due to evolved resistance to treatment. While efforts have been made to combine targeted therapies, significant levels of toxicity have stymied efforts to effectively treat cancer with multi-drug combinations using currently approved therapeutics. We discuss the relationship between tumor-promoting inflammation and cancer as part of a larger effort to develop a broad-spectrum therapeutic approach aimed at a wide range of targets to address this heterogeneity. Specifically, macrophage migration inhibitory factor, cyclooxygenase-2, transcription factor nuclear factor-κB, tumor necrosis factor alpha, inducible nitric oxide synthase, protein kinase B, and CXC chemokines are reviewed as important antiinflammatory targets while curcumin, resveratrol, epigallocatechin gallate, genistein, lycopene, and anthocyanins are reviewed as low-cost, low toxicity means by which these targets might all be reached simultaneously. Future translational work will need to assess the resulting synergies of rationally designed antiinflammatory mixtures (employing low-toxicity constituents), and then combine this with similar approaches targeting the most important pathways across the range of cancer hallmark phenotypes

Inhibition of Src kinase activity attenuates amyloid associated microgliosis in a murine model of Alzheimer’s disease

<p>Abstract</p> <p>Background</p> <p>Microglial activation is an important histologic characteristic of the pathology of Alzheimer’s disease (AD). One hypothesis is that amyloid beta (Aβ) peptide serves as a specific stimulus for tyrosine kinase-based microglial activation leading to pro-inflammatory changes that contribute to disease. Therefore, inhibiting Aβ stimulation of microglia may prove to be an important therapeutic strategy for AD.</p> <p>Methods</p> <p>Primary murine microglia cultures and the murine microglia cell line, BV2, were used for stimulation with fibrillar Aβ1-42. The non-receptor tyrosine kinase inhibitor, dasatinib, was used to treat the cells to determine whether Src family kinase activity was required for the Aβ stimulated signaling response and subsequent increase in TNFα secretion using Western blot analysis and enzyme-linked immunosorbent assay (ELISA), respectively. A histologic longitudinal analysis was performed using an AD transgenic mouse model, APP/PS1, to determine an age at which microglial protein tyrosine kinase levels increased in order to administer dasatinib via mini osmotic pump diffusion. Effects of dasatinib administration on microglial and astroglial activation, protein phosphotyrosine levels, active Src kinase levels, Aβ plaque deposition, and spatial working memory were assessed via immunohistochemistry, Western blot, and T maze analysis.</p> <p>Results</p> <p>Aβ fibrils stimulated primary murine microglia via a tyrosine kinase pathway involving Src kinase that was attenuated by dasatinib. Dasatinib administration to APP/PS1 mice decreased protein phosphotyrosine, active Src, reactive microglia, and TNFα levels in the hippocampus and temporal cortex. The drug had no effect on GFAP levels, Aβ plaque load, or the related tyrosine kinase, Lyn. These anti-inflammatory changes correlated with improved performance on the T maze test in dasatinib infused animals compared to control animals.</p> <p>Conclusions</p> <p>These data suggest that amyloid dependent microgliosis may be Src kinase dependent <it>in vitro</it> and <it>in vivo.</it> This study defines a role for Src kinase in the microgliosis characteristic of diseased brains and suggests that particular tyrosine kinase inhibition may be a valid anti-inflammatory approach to disease. Dasatinib is an FDA-approved drug for treating chronic myeloid leukemia cancer with a reported ability to cross the blood-brain barrier. Therefore, this suggests a novel use for this drug as well as similar acting molecules.</p

Addressing positioning and seating challenges in geriatric residents of a skilled nursing facility that use manual wheelchairs

Participants in the author’s training program for OT practitioners who work in skilled nursing facilities will gain an understanding of the need and requirements for ongoing wheelchair seating and positioning management of long-term care residents. BACKGROUND: Elderly individuals admitted to a skilled nursing facility receive initial occupational therapy (OT) evaluation for appropriate wheelchair (WC) seating. On extended stay, the resident’s seating needs often change, leading to postural impairment from improper positioning. Lack of awareness of poor positioning by residents, particularly when cognitive issues are present, can delay corrective action because they may not call attention to difficulties or discomfort. Occupational therapy practitioners (OTPs) can play a distinctive role in ensuring that proper wheelchair seating and positioning of older residents is maintained. The author’s aim is to create a prototype program designed to mitigate the risk that accompanies poor wheelchair positioning and that can be carried out at any skilled nursing facility (SNF). OBJECTIVES: The author’s project will address the recognized need for a training program for occupational therapy practitioners that will provide guidelines for assessing, evaluating and planning the appropriate intervention for an elderly manual wheelchair user in a skilled nursing facility. Objectives for the resident include reduction in the incidence of wound development, improvement of functioning, and increase in participation in the care environment with other wheelchair users. METHOD: Program implementation will begin with facility recruitment. The author will create a handout illustrating the planned program and will distribute it in person or via mail to administrators of skilled nursing and residential care facilities within a 100-mile radius that have a rehabilitation department and one or more OT practitioners. When interest is expressed by a recipient, the author will contact the facility and conduct a short interview to discuss problems and concerns, the availability of staff incentives for participation in inservice training, and payment for the author’s services. Depending upon the author’s assessment of participant knowledge, skills and needs, training will be adjusted from an introductory to intermediate level. As part of the proposed program, the author will recommend that OT practitioners instruct nursing and other caregiving staff to periodically screen every wheelchair-dependent resident when they are providing direct care during their daily routines. Miller, Miller, Trenholm, Grant and Goodman (2004) developed the Seating Identification Tool (SIT) to fill the need for an easy to administer screening questionnaire that would be sufficiently sensitive for clinical assessment and research. ANTICIPATED FINDINGS: Occupational therapy practitioners will play a distinctive role in ensuring that proper wheelchair seating and positioning of older residents is maintained. Preventing pressure ulcers will prove to be much less costly than medical treatment, both to the resident and the facility. Reduction in time lost from daily occupations to allow healing will improve the client’s sense of well-being. OT practitioners will be called upon to make periodic adjustments in wheelchair fitting and positioning, which might as simple as providing an appropriate wheelchair cushion. LIMITATIONS: Program development and program evaluation research are in the initial stages and have not yet been implemented in any skilled nursing facility. RECOMMENDATIONS: The author recommends implementation of the pilot program in a skilled nursing facility with data gathering for program evaluation research to gain evidence and further refine the program

Recent developments in urea biosensors

This paper reviews recent developments in urea biosensors, as reported in the literature. The advantages and roles of various matrices, different strategies for biosensor construction, analytical performance and applications are discussed. The prospects of urea biosensors for medical applications are also discussed

Potentiation of antimalarial activity of arteether in combination with Vetiver root extract

315-321<span style="font-size:11.0pt;mso-bidi-font-size: 10.0pt;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:"times="" roman";mso-ansi-language:en-gb;mso-fareast-language:="" en-us;mso-bidi-language:ar-sa"="" lang="EN-GB">In malaria, development of resistance towards artemisinin derivatives has urged the need for new drugs or new drug combinations to tackle the drug resistant malaria. We studied the fresh root extract of Vetiver zizanioides (Linn.) Nash (VET) with a CDRI-CIMAP antimalarial α/β arteether (ART) together for their antimalarial potential. Our results showed additive to synergistic antimalarial activity of VET and ART with sum fractional inhibitory concentrations Σ FICs 1.02±0.24 and 1.12±0.32 for chloroquine sensitive (CQS) and chloroquine resistant (CQR) strain of Plasmodium falciparum (William H. Welch), respectively. Further, these combinations were explored against multidrug resistant rodent malaria parasite i.e. <i style="mso-bidi-font-style: normal">P. yoelii nigeriensis. Analysis of in vivo interaction of ART and VET showed that 10 mg/kg×5days of ART with 1000 mg/kg of VET ×5 days cured 100% mice infected with MDR parasite, while the same dose of ART could produce only up to 30% cure and VET fraction was not curative at all. Synergism/additiveness, found between VET and ART is reported for the first time. The curative dose of ART in the combination was reduced to its one fourth, and thus limits the side effects, if any. Although antimalarial potential of ART was enhanced by VET, action mechanism of later needs to be elucidated in detail.</span

Open Access

Regulatory role of TRIM21 in the type-I interferon pathway in Japanese encephalitis virus-infected human microglial cell