Gene therapy for Alzheimer's disease targeting CD33 reduces amyloid beta accumulation and neuroinflammation.

Neuroinflammation is a key contributor to the pathology of Alzheimer's disease (AD). CD33 (Siglec-3) is a transmembrane sialic acid-binding receptor on the surface of microglial cells. CD33 is upregulated on microglial cells from post-mortem AD patient brains, and high levels of CD33 inhibit uptake and clearance of amyloid beta (Aß) in microglial cell cultures. Furthermore, knockout of CD33 reduces amyloid plaque burden in mouse models of AD. Here, we tested whether a gene therapy strategy to reduce CD33 on microglia in AD could decrease Aß plaque load. Intracerebroventricular injection of an adeno-associated virus (AAV) vector-based system encoding an artificial microRNA targeting CD33 (miRCD33) into APP/PS1 mice reduced CD33 mRNA and TBS-soluble Aß40 and Aß42 levels in brain extracts. Treatment of APP/PS1 mice with miRCD33 vector at an early age (2 months) was more effective at reducing Aß plaque burden than intervening at later times (8 months). Furthermore, early intervention downregulated several microglial receptor transcripts (e.g. CD11c, CD47 and CD36) and pro-inflammatory activation genes (e.g. Tlr4 and Il1b). Marked reductions in the chemokine Ccl2 and the pro-inflammatory cytokine Tnfα were observed at the protein level in the brain of APP/PS1 mice treated with miRCD33 vector. Overall, our data indicate that CD33 is a viable target for AAV-based knockdown strategies to reduce AD pathology. One Sentence Summary: A gene therapy approach for Alzheimer's disease using adeno-associated virus vector-based knockdown of CD33 reduced amyloid beta accumulation and neuroinflammation.

Indian Academy of Pediatrics Guidelines on the Fast and Junk Foods, Sugar Sweetened Beverages, Fruit Juices, and Energy Drinks.

JUSTIFICATION: In view of easy availability and increasing trend of consumption of fast foods and sugar sweetened beverages (fruit juices and drinks, carbonated drinks, energy drinks) in Indian children, and their association with increasing obesity and related non-communicable diseases, there is a need to develop guidelines related to consumption of foods and drinks that have the potential to increase this problem in children and adolescents. OBJECTIVES: To review the evidence and formulate consensus statements related to terminology, magnitude of problem and possible ill effects of junk foods, fast foods, sugar-sweetened beverages and carbonated drinks; and to formulate recommendations for limiting consumption of these foods and beverages in Indian children and adolescents. PROCESS: A National Consultative group constituted by the Nutrition Chapter of the Indian Academy of Pediatrics (IAP), consisting of various stakeholders in private and public sector, reviewed the literature and existing guidelines and policy regulations. Detailed review of literature was circulated to the members, and the Group met on 11th March 2019 at New Delhi for a day-long deliberation on framing the guidelines. The consensus statements and recommendations formulated by the Group were circulated to the participants and a consensus document was finalized. CONCLUSIONS: The Group suggests a new acronym 'JUNCS' foods, to cover a wide variety of concepts related to unhealthy foods (Junk foods, Ultra-processed foods, Nutritionally inappropriate foods, Caffeinated/colored/carbonated foods/beverages, and Sugar-sweetened beverages). The Group concludes that consumption of these foods and beverages is associated with higher free sugar and energy intake; and is associated with higher body mass index (and possibly with adverse cardiometabolic consequences) in children and adolescents. Intake of caffeinated drinks may be associated with cardiac and sleep disturbances. The Group recommends avoiding consumption of the JUNCS by all children and adolescents as far as possible and limit their consumption to not more than one serving per week. The Group recommends intake of regional and seasonal whole fruits over fruit juices in children and adolescents, and advises no fruit juices/drinks to infants and young children (age <2y), whereas for children aged 2-5 y and >5-18 y, their intake should be limited to 125 mL/day and 250mL/day, respectively. The Group recommends that caffeinated energy drinks should not be consumed by children and adolescents. The Group supports recommendations of ban on sale of JUNCS foods in school canteens and in near vicinity, and suggests efforts to ensure availability and affordability of healthy snacks and foods. The Group supports traffic light coding of food available in school canteens and recommends legal ban of screen/print/digital advertisements of all the JUNCS foods for channels/magazines/websites/social media catering to children and adolescents. The Group further suggests communication, marketing and policy/taxation strategies to promote consumption of healthy foods, and limit availability and consumption of the JUNCS foods.

Opposing Roles of apolipoprotein E in aging and neurodegeneration.

Apolipoprotein E (APOE) effects on brain function remain controversial. Removal of APOE not only impairs cognitive functions but also reduces neuritic amyloid plaques in mouse models of Alzheimer's disease (AD). Can APOE simultaneously protect and impair neural circuits? Here, we dissociated the role of APOE in AD versus aging to determine its effects on neuronal function and synaptic integrity. Using two-photon calcium imaging in awake mice to record visually evoked responses, we found that genetic removal of APOE improved neuronal responses in adult APP/PSEN1 mice (8-10 mo). These animals also exhibited fewer neuritic plaques with less surrounding synapse loss, fewer neuritic dystrophies, and reactive glia. Surprisingly, the lack of APOE in aged mice (18-20 mo), even in the absence of amyloid, disrupted visually evoked responses. These results suggest a dissociation in APOE's role in AD versus aging: APOE may be neurotoxic during early stages of amyloid deposition, although being neuroprotective in latter stages of aging.

Virus vector-mediated genetic modification of brain tumor stromal cells after intravenous delivery.

The malignant primary brain tumor, glioblastoma (GBM) is generally incurable. New approaches are desperately needed. Adeno-associated virus (AAV) vector-mediated delivery of anti-tumor transgenes is a promising strategy, however direct injection leads to focal transgene spread in tumor and rapid tumor division dilutes out the extra-chromosomal AAV genome, limiting duration of transgene expression. Intravenous (IV) injection gives widespread distribution of AAV in normal brain, however poor transgene expression in tumor, and high expression in non-target cells which may lead to ineffective therapy and high toxicity, respectively. Delivery of transgenes encoding secreted, anti-tumor proteins to tumor stromal cells may provide a more stable and localized reservoir of therapy as they are more differentiated than fast-dividing tumor cells. Reactive astrocytes and tumor-associated macrophage/microglia (TAMs) are stromal cells that comprise a large portion of the tumor mass and are associated with tumorigenesis. In mouse models of GBM, we used IV delivery of exosome-associated AAV vectors driving green fluorescent protein expression by specific promoters (NF-κB-responsive promoter and a truncated glial fibrillary acidic protein promoter), to obtain targeted transduction of TAMs and reactive astrocytes, respectively, while avoiding transgene expression in the periphery. We used our approach to express the potent, yet toxic anti-tumor cytokine, interferon beta, in tumor stroma of a mouse model of GBM, and achieved a modest, yet significant enhancement in survival compared to controls. Noninvasive genetic modification of tumor microenvironment represents a promising approach for therapy against cancers. Additionally, the vectors described here may facilitate basic research in the study of tumor stromal cells in situ.

Intimate partner violence and cancer screening among urban minority women.

PURPOSE: To evaluate the association of intimate partner violence (IPV) with breast and cervical cancer screening rates. METHODS: We conducted retrospective chart audits of 382 adult women at 4 urban family medicine practices. Inclusion criteria were not being pregnant, no cancer history, and having a partner. Victims were defined as those who screened positive on at least one of 2 brief IPV screening tools: the HITS (Hurt, Insult, Threat, Scream) tool or Women Abuse Screening Tool (short). Logistic regression models were used to examine whether nonvictims, victims of emotional abuse, and victims of physical and/or sexual abuse were up to date for mammograms and Papanicolaou smears. RESULTS: Prevalence of IPV was 16.5%. Compared with victims of emotional abuse only, victims of physical and/or sexual abuse aged 40 to 74 were associated with 87% decreased odds of being up to date on Papanicolaou smears (odds ratio, 0.13; 95% CI, 0.02-0.86) and 84% decreased odds of being up to date in mammography (odds ratio, 0.16; 95% CI, 0.03-0.99). There was no difference in Papanicolaou smear rates among female victims and nonvictims younger than 40. CONCLUSIONS: Because of the high prevalence of IPV, screening is essential among all women. Clinicians should ensure that victims of physical and/or sexual abuse are screened for cervical cancer and breast cancer, particularly women aged 40 or older. Cancer screening promotion programs are needed for victims of abuse.