Marine-Derived Anticancer Agents Targeting Apoptotic Pathways: Exploring the Depths for Novel Cancer Therapies.

Extensive research has been conducted on the isolation and study of bioactive compounds derived from marine sources. Several natural products have demonstrated potential as inducers of apoptosis and are currently under investigation in clinical trials. These marine-derived compounds selectively interact with extrinsic and intrinsic apoptotic pathways using a variety of molecular mechanisms, resulting in cell shrinkage, chromatin condensation, cytoplasmic blebs, apoptotic bodies, and phagocytosis by adjacent parenchymal cells, neoplastic cells, or macrophages. Numerous marine-derived compounds are currently undergoing rigorous examination for their potential application in cancer therapy. This review examines a total of 21 marine-derived compounds, along with their synthetic derivatives, sourced from marine organisms such as sponges, corals, tunicates, mollusks, ascidians, algae, cyanobacteria, fungi, and actinobacteria. These compounds are currently undergoing preclinical and clinical trials to evaluate their potential as apoptosis inducers for the treatment of different types of cancer. This review further examined the compound's properties and mode of action, preclinical investigations, clinical trial studies on single or combination therapy, and the prospective development of marine-derived anticancer therapies.

Kismet/CHD7/CHD8 and Amyloid Precursor Protein-like Regulate Synaptic Levels of Rab11 at the Drosophila Neuromuscular Junction.

The transmembrane protein ß-amyloid precursor protein (APP) is central to the pathophysiology of Alzheimer's disease (AD). The ß-amyloid hypothesis posits that aberrant processing of APP forms neurotoxic ß-amyloid aggregates, which lead to the cognitive impairments observed in AD. Although numerous additional factors contribute to AD, there is a need to better understand the synaptic function of APP. We have found that Drosophila APP-like (APPL) has both shared and non-shared roles at the synapse with Kismet (Kis), a chromatin helicase binding domain (CHD) protein. Kis is the homolog of CHD7 and CHD8, both of which are implicated in neurodevelopmental disorders including CHARGE Syndrome and autism spectrum disorders, respectively. Loss of function mutations in kis and animals expressing human APP and BACE in their central nervous system show reductions in the glutamate receptor subunit, GluRIIC, the GTPase Rab11, and the bone morphogenetic protein (BMP), pMad, at the Drosophila larval neuromuscular junction (NMJ). Similarly, processes like endocytosis, larval locomotion, and neurotransmission are deficient in these animals. Our pharmacological and epistasis experiments indicate that there is a functional relationship between Kis and APPL, but Kis does not regulate appl expression at the larval NMJ. Instead, Kis likely influences the synaptic localization of APPL, possibly by promoting rab11 transcription. These data identify a potential mechanistic connection between chromatin remodeling proteins and aberrant synaptic function in AD.

The CHD Protein Kismet Restricts the Synaptic Localization of Cell Adhesion Molecules at the Drosophila Neuromuscular Junction.

The appropriate expression and localization of cell surface cell adhesion molecules must be tightly regulated for optimal synaptic growth and function. How neuronal plasma membrane proteins, including cell adhesion molecules, cycle between early endosomes and the plasma membrane is poorly understood. Here we show that the Drosophila homolog of the chromatin remodeling enzymes CHD7 and CHD8, Kismet, represses the synaptic levels of several cell adhesion molecules. Neuroligins 1 and 3 and the integrins αPS2 and ßPS are increased at kismet mutant synapses but Kismet only directly regulates transcription of neuroligin 2. Kismet may therefore regulate synaptic CAMs indirectly by activating transcription of gene products that promote intracellular vesicle trafficking including endophilin B (endoB) and/or rab11. Knock down of EndoB in all tissues or neurons increases synaptic FasII while knock down of EndoB in kis mutants does not produce an additive increase in FasII. In contrast, neuronal expression of Rab11, which is deficient in kis mutants, leads to a further increase in synaptic FasII in kis mutants. These data support the hypothesis that Kis influences the synaptic localization of FasII by promoting intracellular vesicle trafficking through the early endosome.

Presence of ovarian stromal aberrations after cessation of testosterone therapy in a transgender mouse model†.

Some transmasculine individuals may be interested in pausing gender-affirming testosterone therapy and carrying a pregnancy. The ovarian impact of taking and pausing testosterone is not completely understood. The objective of this study was to utilize a mouse model mimicking transmasculine testosterone therapy to characterize the ovarian dynamics following testosterone cessation. We injected postpubertal 9-10-week-old female C57BL/6N mice once weekly with 0.9 mg of testosterone enanthate or a vehicle control for 6 weeks. All testosterone-treated mice stopped cycling and demonstrated persistent diestrus within 1 week of starting testosterone, while control mice cycled regularly. After 6 weeks of testosterone therapy, one group of testosterone-treated mice and age-matched vehicle-treated diestrus controls were sacrificed. Another group of testosterone-treated mice were maintained after stopping testosterone therapy and were sacrificed in diestrus four cycles after the resumption of cyclicity along with age-matched vehicle-treated controls. Ovarian histological analysis revealed stromal changes with clusters of large round cells in the post testosterone group as compared to both age-matched controls and mice at 6 weeks on testosterone. These clusters exhibited periodic acid-Schiff staining, which has been previously reported in multinucleated macrophages in aging mouse ovaries. Notably, many of these cells also demonstrated positive staining for macrophage markers CD68 and CD11b. Ovarian ribonucleic acid-sequencing found upregulation of immune pathways post testosterone as compared to age-matched controls and ovaries at 6 weeks on testosterone. Although functional significance remains unknown, further attention to the ovarian stroma may be relevant for transmasculine people interested in pausing testosterone to carry a pregnancy.

A mouse model mimicking gender-affirming treatment with pubertal suppression followed by testosterone in transmasculine youth.

STUDY QUESTION: Can mice serve as a translational model to examine the reproductive consequences of pubertal suppression with GnRH agonist (GnRHa) followed by testosterone (T) administration, a typical therapy in peripubertal transmasculine youth? SUMMARY ANSWER: An implanted depot with 3.6 mg of GnRHa followed by T enanthate at 0.45 mg weekly can be used in peripubertal female mice for investigating the impact of gender-affirming hormone therapy in transmasculine youth. WHAT IS KNOWN ALREADY: There is limited knowledge available in transgender medicine to provide evidence-based fertility care, with the current guidelines being based on the assumption of fertility loss. We recently successfully developed a mouse model to investigate the reproductive consequences of T therapy given to transgender men. On the other hand, to our knowledge, there is no mouse model to assess the reproductive outcomes in peripubertal transmasculine youth. STUDY DESIGN, SIZE, DURATION: A total of 80 C57BL/6N female mice were used in this study, with n = 7 mice in each experimental group. PARTICIPANTS/MATERIALS, SETTING, METHODS: We first assessed the effectiveness of GnRHa in arresting pubertal development in the female mice. In this experiment, 26-day-old female mice were subcutaneously implanted with a GnRHa (3.6 mg) depot. Controls underwent a sham surgery. Animals were euthanized at 3, 9, 21 and 28 days after the day of surgery. In the second experiment, we induced a transmasculine youth mouse model. C57BL/6N female mice were subcutaneously implanted with a 3.6 mg GnRHa depot on postnatal day 26 for 21 days and this was followed by weekly injections of 0.45 mg T enanthate for 6 weeks. The control for the GnRH treatment was sham surgery and the control for T treatment was sesame oil vehicle injections. Animals were sacrificed 0.5 weeks after the last injection. The data collected included the day of the vaginal opening and first estrus, daily vaginal cytology, weekly and terminal reproductive hormones levels, body/organ weights, ovarian follicular distribution and corpora lutea (CL) counts. MAIN RESULTS AND THE ROLE OF CHANCE: GnRHa implanted animals remained in persistent diestrus and had reduced levels of FSH (P = 0.0013), LH (P = 0.0082) and estradiol (P = 0.0155), decreased uterine (P < 0.0001) and ovarian weights (P = 0.0002), and a lack of CL at 21 days after GnRHa implantation. T-only and GnRHa+T-treated animals were acyclic throughout the treatment period, had sustained elevated levels of T, suppressed LH levels (P < 0.0001), and an absence of CL compared to controls (P < 0.0001). Paired ovarian weights were reduced in the T-only and GnRHa+T groups compared with the control and GnRHa-only groups. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Although it is an appropriate tool to provide relevant findings, precaution is needed to extrapolate mouse model results to mirror human reproductive physiology. WIDER IMPLICATIONS OF THE FINDINGS: To our knowledge, this study describes the first mouse model mimicking gender-affirming hormone therapy in peripubertal transmasculine youth. This model provides a tool for researchers studying the effects of GnRHa-T therapy on other aspects of reproduction, other organ systems and transgenerational effects. The model is supported by GnRHa suppressing puberty and maintaining acyclicity during T treatment, lower LH levels and absence of CL. The results also suggest GnRHa+T therapy in peripubertal female mice does not affect ovarian reserve, since the number of primordial follicles was not affected by treatment. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the Michigan Institute for Clinical and Health Research grants KL2 TR 002241 and UL1 TR 002240 (C.D.C.); National Institutes of Health grants F30-HD100163 and T32-HD079342 (H.M.K.); University of Michigan Office of Research funding U058227 (A.S.); American Society for Reproductive Medicine/Society for Reproductive Endocrinology and Infertility grant (M.B.M.); and National Institutes of Health R01-HD098233 (M.B.M.). The University of Virginia Center for Research in Reproduction Ligand Assay and Analysis Core Facility was supported by the Eunice Kennedy Shriver NICHD/NIH grants P50-HD028934 and R24-HD102061. The authors declare that they have no competing interests.

Use of N-(4-aminophenyl)piperidine derivatization to improve organic acid detection with supercritical fluid chromatography-mass spectrometry.

The analysis of organic acids in complex mixtures by LC-MS can often prove challenging, especially due to the poor sensitivity of negative ionization mode required for detection of these compounds in their native (i.e., underivatized or untagged) form. These compounds have also been difficult to measure using supercritical fluid chromatography (SFC)-MS, a technique of growing importance for metabolomic analysis, with similar limitations based on negative ionization. In this report, the use of a high proton affinity N-(4-aminophenyl)piperidine derivatization tag is explored for the improvement of organic acid detection by SFC-MS. Four organic acids (lactic, succinic, malic, and citric acids) with varying numbers of carboxylate groups were derivatized with N-(4-aminophenyl)piperidine to achieve detection limits down to 0.5 ppb, with overall improvements in detection limit ranging from 25-to-2100-fold. The effect of the derivatization group on sensitivity, which increased by at least 200-fold for compounds that were detectable in their native form, and mass spectrometric detection are also described. Preliminary investigations into the separation of these derivatized compounds identified multiple stationary phases that could be used for complete separation of all four compounds by SFC. This derivatization technique provides an improved approach for the analysis of organic acids by SFC-MS, especially for those that are undetectable in their native form.

Prompted hands-free drinking improves simulated race car driving in a hot environment.

Race car drivers are often hypohydrated during a race. The FluidLogic drink system is a hands-free, prompted drinking system that is hypothesized to increase the likeliness of drivers' consuming fluids and thereby mitigating hypohydration. To test the hypothesis, 20 elite professional race car drivers participated in a 2-day cross-over study in which they drove on a race simulator in an environmental chamber that was heated to regulation cockpit temperature (38°C). Drivers used either the FluidLogic drink system or a standard in-car water bottle system (Control) on one of each testing day. The results indicated that there was consistent fluid consumption with the FluidLogic system, while the Control condition elicited fluid consumption in bolus doses. The Control condition was associated with moderate (0.5%) increased core body temperature (P < 0.05) and substantial (3.3%) increased urine-specific gravity (P < 0.001) as compared to the FluidLogic condition. Driving performance metrics indicated that lap times during the Control Condition were 5.1 ± 1.4 (4.1%) seconds slower (P < 0.05) than the FluidLogic Condition, due to driving errors that occurred in the high-speed corners. Based on these results, prompted hands-free drinking can mitigate hypohydration and performance loss in automobile racing drivers.

Multitarget Stool RNA Test for Colorectal Cancer Screening.

Importance: Noninvasive tests for colorectal cancer screening must include sensitive detection of colorectal cancer and precancerous lesions. These tests must be validated for the intended-use population, which includes average-risk individuals 45 years or older. Objective: To evaluate the sensitivity and specificity of a noninvasive, multitarget stool RNA (mt-sRNA) test (ColoSense) test compared with results from a colonoscopy. Design, Setting, and Participants: This phase 3 clinical trial (CRC-PREVENT) was a blinded, prospective, cross-sectional study to support a premarket approval application for a class III medical device. A total of 8920 participants were identified online using social media platforms and enrolled from June 2021 to June 2022 using a decentralized nurse call center. All participants completed the mt-sRNA test, which incorporated a commercially available fecal immunochemical test (FIT), concentration of 8 RNA transcripts, and participant-reported smoking status. Stool samples were collected prior to participants completing a colonoscopy at their local endoscopy center. The mt-sRNA test results (positive or negative) were compared with index lesions observed on colonoscopy. Over the course of 12 months, individuals 45 years and older were enrolled in the clinical trial using the decentralized recruitment strategy. Participants were enrolled from 49 US states and obtained colonoscopies at more than 3800 different endoscopy centers. Main Outcomes and Measures: The primary outcomes included the sensitivity of the mt-sRNA test for detecting colorectal cancer and advanced adenomas and the specificity for no lesions on colonoscopy. Results: The mean (range) age of participants was 55 (45-90) years, with 4% self-identified as Asian, 11% as Black, and 7% as Hispanic. Of the 8920 eligible participants, 36 (0.40%) had colorectal cancer and 606 (6.8%) had advanced adenomas. The mt-sRNA test sensitivity for detecting colorectal cancer was 94%, sensitivity for detecting advanced adenomas was 46%, and specificity for no lesions on colonoscopy was 88%. The mt-sRNA test showed significant improvement in sensitivity for colorectal cancer (94% vs 78%; McNemar P = .01) and advanced adenomas (46% vs 29%; McNemar P < .001) compared with results of the FIT. Conclusions and Relevance: In individuals 45 years and older, the mt-sRNA test showed high sensitivity for colorectal neoplasia (colorectal cancer and advanced adenoma) with significant improvement in sensitivity relative to the FIT. Specificity for no lesions on colonoscopy was comparable to existing molecular diagnostic tests. Trial Registration: ClinicalTrials.gov Identifier: NCT04739722.

The Biosynthetic Landscape of Triceptides Reveals Radical SAM Enzymes That Catalyze Cyclophane Formation on Tyr- and His-Containing Motifs.

Peptide-derived cyclophanes inhabit a unique niche in the chemical space of macrocyclic peptides with several examples of pharmaceutical importance. Although both synthetic and biocatalytic methods are available for constructing these macrocycles, versatile (bio)catalysts able to incorporate a variety of amino acids that compose the macrocycle would be useful for the creation of diverse peptide cyclophanes. In this report, we synergized the use of bioinformatic tools to map the biosynthetic landscape of radical SAM enzymes (3-CyFEs) that catalyze three-residue cyclophane formation in the biosynthesis of a new family of RiPP natural products, the triceptides. This analysis revealed 3940 (3113 unique) putative precursor sequences predicted to be modified by 3-CyFEs. Several uncharacterized maturase systems were identified that encode unique precursor types. Functional studies were carried out in vivo in Escherichia coli to identify modified precursors containing His and Tyr residues. NMR analysis of the products revealed that Tyr and His can also be incorporated into cyclophane macrocycles by 3-CyFEs. Collectively, all aromatic amino acids can be incorporated by 3-CyFEs, and the cyclophane formation strictly occurs via a C(sp2)-C(sp3) cross-link between the (hetero)aromatic ring to Cß. In addition to 3-CyFEs, we functionally validated an Fe(II)/α-ketoglutarate-dependent hydroxylase, resulting in ß-hydroxylated residues within the cyclophane rings. This study reveals the potential breadth of triceptide precursors and a systematic approach for studying these enzymes to broaden the diversity of peptide macrocycles.

A Distant Ally?: Mortality Salience and Parasocial Attachment.

Research in Terror Management Theory finds that close interpersonal relationships (e.g., parents, romantic partners) mitigate threat reactions to reminders of mortality. Parasocial relationships (imagined relationships with media personalities) afford many of the same benefits as interpersonal relationships. Do these benefits extend to mortality concerns? We investigated whether those with strong parasocial attachments were differentially influenced by reminders of death. Results showed that those with strong parasocial relationships had more defensive reactions to a mortality prime, suggesting that such attachments may not afford the same existential benefits given by close human others and may instead indicate a heightened vulnerability.

The effect of botulinum toxin on ureteral inflammation.

PURPOSE: The impact of onabotulinum toxin type A (BoNT-A) on bladder afferent nerve pathways and chemosensory functions is an active area of investigation. There may be a role for BoNT-A in disorders of the ureter; however, no histologic studies have assessed the effects of BoNT-A on ureteral tissue. Our objective was to develop an animal model of ureteral inflammation and determine the impact of ureteral BoNT-A instillation on known mechanisms of inflammation. METHODS: The safety and feasibility of a novel animal model of ureteral inflammation was assessed. Through open cystotomy, the effect of ureteral BoNT-A instillation on inflammation was determined through H&E, masson's trichrome, Ki-67 stain, and prostaglandin E (PGE) synthase expression, a known marker of pain and inflammation in ureteral tissue. Urothelial microstructure was assessed using electron microscopy and standard histologic techniques. RESULTS: All experiments were carried to completion, and no systemic signs of botulinum toxicity were seen. BoNT-A exposure was associated with a decrease in PGE synthase expression in a dose-dependent fashion. BoNT-A exposure was not found to impact collagen deposition or cell proliferation. Disruption of tight junctions between urothelial cells was observed under conditions of inflammation. CONCLUSION: We describe the feasibility of a novel in vivo model of ureteral inflammation and report the first histologic study of the effects of BoNT-A on the ureter. Preliminary findings show that BoNT-A attenuates ureteral PGE synthase expression under conditions of inflammation. The application of BoNT-A may provide anti-inflammatory and analgesic effects in the context of ureteral disorders.

The Isorhamnetin-Containing Fraction of Philippine Honey Produced by the Stingless Bee Tetragonula biroi Is an Antibiotic against Multidrug-Resistant Staphylococcus aureus.

Honey exhibits antibacterial and antioxidant activities that are ascribed to its diverse secondary metabolites. In the Philippines, the antibacterial and antioxidant activities, as well as the bioactive metabolite contents of the honey, have not been thoroughly described. In this report, we investigated the in vitro antibacterial and antioxidant activities of honey from Apis mellifera and Tetragonula biroi, identified the compound responsible for the antibacterial activity, and compared the observed bioactivities and metabolite profiles to that of Manuka honey, which is recognized for its antibacterial and antioxidant properties. The secondary metabolite contents of honey were extracted using a nonionic polymeric resin followed by antibacterial and antioxidant assays, and then spectroscopic analyses of the phenolic and flavonoid contents. Results showed that honey extracts produced by T. biroi exhibits antibiotic activity against Staphylococcal pathogens as well as high antioxidant activity, which are correlated to its high flavonoid and phenolic content as compared to honey produced by A. mellifera. The bioassay-guided fractionation paired with Liquid Chromatography Mass Spectrometry (LCMS) and tandem MS analyses found the presence of the flavonoid isorhamnetin (3-methylquercetin) in T. biroi honey extract, which was demonstrated as one of the compounds with inhibitory activity against multidrug-resistant Staphylococcus aureus ATCC BAA-44. Our findings suggest that Philippine honey produced by T. biroi is a potential nutraceutical that possesses antibiotic and antioxidant activities.

Slc6a3-dependent expression of a CAPS-associated Nlrp3 allele results in progressive behavioral abnormalities and neuroinflammation in aging mice.

BACKGROUND: An association between neuroinflammation and age-related neurologic disorders has been established but the molecular mechanisms and cell types involved have not been thoroughly characterized. Activity of the proinflammatory NLRP3 inflammasome is implicated in Alzheimer's and Parkinson's disease and our recent studies in patients suggest that dopaminergic neurons within the degenerating mesencephalon express NLRP3 throughout the progression of PD. Here, we directly test the impact of enhanced inflammasome activity in mesencephalic neurons by characterizing motor function, tissue integrity, and neuroinflammation in aging mice harboring hyperactivating mutations within the endogenous murine Nlrp3 locus, enabled only in cells expressing the dopaminergic neuron-specific Slc6a3 promoter. METHODS: We compared mice harboring inducible alleles encoding the cryopyrin-associated periodic syndrome activating mutations Nlrp3A350V and Nlrp3L351P inserted into the endogenous mouse Nlrp3 locus. Tissue specific expression was driven by breeding these animals with mice expressing Cre recombinase under the control of the dopaminergic neuron-specific Slc6a3 promoter. The experimental mice, designed to express hyperactive NLRP3 only when the endogenous mouse Nlrp3 promotor is active in dopaminergic neurons, were analyzed throughout 18 months of aging using longitudinal motor function assessments. Biochemical and histologic analyses of mesencephalic tissues were conducted in 1- and 18-month-old animals. RESULTS: We observed progressive and significant deficits in motor function in animals expressing Nlrp3L351P, compared with animals expressing Nlrp3WT and Nlrp3A350V. Age-dependent neuroinflammatory changes in the mesencephalon were noted in all animals. Analysis of GFAP-immunoreactive astrocytes in the substantia nigra revealed a significant increase in astrocyte number in animals expressing Nlrp3L351P compared with Nlrp3WT and Nlrp3A350V. Further analysis of Nlrp3L351P striatal tissues indicated genotype specific gliosis, elevated Il1b expression, and both morphologic and gene expression indicators of proinflammatory A1 astrocytes. CONCLUSIONS: Dopaminergic neurons have the potential to accumulate NLRP3 inflammasome activators with age, including reactive oxygen species, dopamine metabolites, and misfolded proteins. Results indicate the Nlrp3 locus is active in dopaminergic neurons in aging mice, and that the hyperactive Nlrp3L351P allele can drive neuroinflammatory changes in association with progressive behavioral deficits. Findings suggest neuronal NLRP3 inflammasome activity may contribute to neuroinflammation observed during normal aging and the progression of neurologic disorders.

The ovarian stroma as a new frontier.

Historically, research in ovarian biology has focused on folliculogenesis, but recently the ovarian stroma has become an exciting new frontier for research, holding critical keys to understanding complex ovarian dynamics. Ovarian follicles, which are the functional units of the ovary, comprise the ovarian parenchyma, while the ovarian stroma thus refers to the inverse or the components of the ovary that are not ovarian follicles. The ovarian stroma includes more general components such as immune cells, blood vessels, nerves, and lymphatic vessels, as well as ovary-specific components including ovarian surface epithelium, tunica albuginea, intraovarian rete ovarii, hilar cells, stem cells, and a majority of incompletely characterized stromal cells including the fibroblast-like, spindle-shaped, and interstitial cells. The stroma also includes ovarian extracellular matrix components. This review combines foundational and emerging scholarship regarding the structures and roles of the different components of the ovarian stroma in normal physiology. This is followed by a discussion of key areas for further research regarding the ovarian stroma, including elucidating theca cell origins, understanding stromal cell hormone production and responsiveness, investigating pathological conditions such as polycystic ovary syndrome (PCOS), developing artificial ovary technology, and using technological advances to further delineate the multiple stromal cell types.

Temporal trends in the sit-ups performance of 9,939,289 children and adolescents between 1964 and 2017.

We estimated international/national temporal trends in sit-ups performance for children and adolescents, and examined relationships between national trends in sit-ups performance and national trends in health-related/sociodemographic indicators. Data were obtained by systematically searching studies reporting on temporal trends in sit-ups performance for apparently healthy 9-17 year-olds, and by examining nationally representative fitness datasets. Trends at the country-sex-age level were estimated by sample-weighted regression models relating the testing year to mean sit-ups performance. International/national trends were estimated by a post-stratified population-weighting procedure. Pearson's correlations quantified relationships between national trends in sit-ups performance and national trends in health-related/sociodemographic indicators. A total of 9,939,289 children and adolescents from 31 countries/special administrative regions between 1964 and 2017 collectively showed a large improvement of 38.4% (95% CI: 36.8 to 40.0) or 7.1% per decade (95% CI: 6.8 to 7.4). Large international improvements were experienced by all age and sex groups, with the rate of improvement slowing from 1964 to 2000, stabilizing near zero until 2010, before declining. Trends differed between countries, with national trends in vigorous physical activity a strong, positive correlate of national trends in sit-ups performance. More sit-ups data are needed from low- and middle-income countries to better monitor trends in muscular fitness. PROSPERO REGISTRATION NUMBER: CRD42013003657.

Epigenetic crosstalk: Pharmacological inhibition of HDACs can rescue defective synaptic morphology and neurotransmission phenotypes associated with loss of the chromatin reader Kismet.

We are beginning to appreciate the complex mechanisms by which epigenetic proteins control chromatin dynamics to tightly regulate normal development. However, the interaction between these proteins, particularly in the context of neuronal function, remains poorly understood. Here, we demonstrate that the activity of histone deacetylases (HDACs) opposes that of a chromatin remodeling enzyme at the Drosophila neuromuscular junction (NMJ). Pharmacological inhibition of HDAC function reverses loss of function phenotypes associated with Kismet, a chromodomain helicase DNA-binding (CHD) protein. Inhibition of HDACs suppresses motor deficits, overgrowth of the NMJ, and defective neurotransmission associated with loss of Kismet. We hypothesize that Kismet and HDACs may converge on a similar set of target genes in the nervous system. Our results provide further understanding into the complex interactions between epigenetic protein function in vivo.

The Notch ligand E3 ligase, Mind Bomb1, regulates glutamate receptor localization in Drosophila.

The postsynaptic density (PSD) is a protein-rich network important for the localization of postsynaptic glutamate receptors (GluRs) and for signaling downstream of these receptors. Although hundreds of PSD proteins have been identified, many are functionally uncharacterized. We conducted a reverse genetic screen for mutations that affected GluR localization using Drosophila genes that encode homologs of mammalian PSD proteins. 42.8% of the mutants analyzed exhibited a significant change in GluR localization at the third instar larval neuromuscular junction (NMJ), a model synapse that expresses homologs of AMPA receptors. We identified the E3 ubiquitin ligase, Mib1, which promotes Notch signaling, as a regulator of synaptic GluR localization. Mib1 positively regulates the localization of the GluR subunits GluRIIA, GluRIIB, and GluRIIC. Mutations in mib1 and ubiquitous expression of Mib1 that lacks its ubiquitin ligase activity result in the loss of synaptic GluRIIA-containing receptors. In contrast, overexpression of Mib1 in all tissues increases postsynaptic levels of GluRIIA. Cellular levels of Mib1 are also important for the structure of the presynaptic motor neuron. While deficient Mib1 signaling leads to overgrowth of the NMJ, ubiquitous overexpression of Mib1 results in a reduction in the number of presynaptic motor neuron boutons and branches. These synaptic changes may be secondary to attenuated glutamate release from the presynaptic motor neuron in mib1 mutants as mib1 mutants exhibit significant reductions in the vesicle-associated protein cysteine string protein and in the frequency of spontaneous neurotransmission.

Formative Work and Community Engagement Approaches for Implementing an HIV Intervention in Botswana Schools.

Providing adolescents with evidence-based sexual risk reduction interventions is critical to addressing the HIV/AIDS epidemic among adolescents in sub-Saharan Africa. Project AIM (Adult Identity Mentoring) is an innovative, evidence-based, youth development intervention that is being evaluated for the first time in Botswana through a 3-year (2015-2017), 50-school cluster randomized controlled trial, including testing for herpes simplex virus type 2 as a sexual activity biomarker. Conducting a trial of this magnitude requires the support and collaboration of government and community stakeholders. All school staff, including teachers, must be well informed about the study; dedicated staff placed at each school can help to improve school and community familiarity with the study, improve the information flow, and relieve some of the burden study activities places on schools.

Responding to Changes in HIV Policy: Updating and Enhancing the Families Matter! Curriculum.

OBJECTIVES: The past decade has seen changes in US HIV policy in sub-Saharan Africa in response to a new Administration and far-reaching technical, scientific and programmatic developments. These include: dramatically increased access to life-saving ART and related services; the roll-out of voluntary medical male circumcision; and growing sensitivity to gender-based violence, including child sexual abuse, and to its role in increasing vulnerability to HIV. The Families Matter! Program (FMP) is an intervention for parents and caregivers of 9-12 year-olds that promotes effective parent-child communication about sexuality and sexual risk reduction. FMP was adapted from a US evidence-based intervention in 2003-4 and is now implemented in eight African countries. In 2012-13, the FMP curriculum was updated and enhanced to respond to new US Government priorities. METHODS: Enhancements to the curriculum drew on the results of Violence Against Children surveys, on a review of existing literature, on feedback from the field on the existing curriculum, and on stories written by young people across Africa for scriptwriting competitions. RESULTS: We updated FMP with scientific content and stronger linkages to services. We also intensified our focus on structural determinants of risk. This contextualisation of sexual risk-taking within structural constraints led us to place greater emphasis on gendered vulnerability and the diverse pressures children face, and to intensify our situation-based pedagogical approach, drawing on the authentic youth-authored narratives. CONCLUSION: We describe these changes as an illustration of and source of insight into much-needed programmatic adaptation in response to evolving HIV policy.

Antiretroviral preexposure prophylaxis for heterosexual HIV transmission in Botswana.

BACKGROUND: Preexposure prophylaxis with antiretroviral agents has been shown to reduce the transmission of human immunodeficiency virus (HIV) among men who have sex with men; however, the efficacy among heterosexuals is uncertain. METHODS: We randomly assigned HIV-seronegative men and women to receive either tenofovir disoproxil fumarate and emtricitabine (TDF-FTC) or matching placebo once daily. Monthly study visits were scheduled, and participants received a comprehensive package of prevention services, including HIV testing, counseling on adherence to medication, management of sexually transmitted infections, monitoring for adverse events, and individualized counseling on risk reduction; bone mineral density testing was performed semiannually in a subgroup of participants. RESULTS: A total of 1219 men and women underwent randomization (45.7% women) and were followed for 1563 person-years (median, 1.1 years; maximum, 3.7 years). Because of low retention and logistic limitations, we concluded the study early and followed enrolled participants through an orderly study closure rather than expanding enrollment. The TDF-FTC group had higher rates of nausea (18.5% vs. 7.1%, P<0.001), vomiting (11.3% vs. 7.1%, P=0.008), and dizziness (15.1% vs. 11.0%, P=0.03) than the placebo group, but the rates of serious adverse events were similar (P=0.90). Participants who received TDF-FTC, as compared with those who received placebo, had a significant decline in bone mineral density. K65R, M184V, and A62V resistance mutations developed in 1 participant in the TDF-FTC group who had had an unrecognized acute HIV infection at enrollment. In a modified intention-to-treat analysis that included the 33 participants who became infected during the study (9 in the TDF-FTC group and 24 in the placebo group; 1.2 and 3.1 infections per 100 person-years, respectively), the efficacy of TDF-FTC was 62.2% (95% confidence interval, 21.5 to 83.4; P=0.03). CONCLUSIONS: Daily TDF-FTC prophylaxis prevented HIV infection in sexually active heterosexual adults. The long-term safety of daily TDF-FTC prophylaxis, including the effect on bone mineral density, remains unknown. (Funded by the Centers for Disease Control and Prevention and the National Institutes of Health; TDF2 ClinicalTrials.gov number, NCT00448669.).