Metabolomic Investigation of Natural Antiplasmodial Agents

Malaria is one of the deadliest parasitic diseases that still plagues humanity in recent times. Despite being target of several eradication campaigns, the widespread presence of the multiple agents that cause this parasitosis, along with its increased adaptability into developing resistance to treatments, make this old ailment a challenge to modern medicine. Natural products with potential antiplasmodial activity are valuable to discover new therapeutic targets and shed light on new scaffolds that can be optimized into revolutionary treatments. In this thesis, metabolomics, a sensitive and robust approach that can describe the metabolites of the malaria parasite maintained in culture, was used to profile the effects of natural products on the parasite and hypothesize their mode of action. Before this could be done, workflow investigation and protocol optimization were carried out, including a study on metabolic extraction methods with state-of-the-art statistical algorithms. Further exploration revealed that time and complexity are detrimental to repeatability and robustness of the results, so a method with a single washing step followed by methanolic 90% extraction was used and analyzed through 1HNMR and/or LC-MS, depending on sample availability. Five individual cases were studied in collaboration with the Department of Biochemistry and Molecular Biology and the Huck Center for Malaria Research at Penn State (The Pennsylvania State University), which allowed the use of their inhouse MS system and database for targeted metabolite annotation. First, an exploration of plant extracts and fractions were studied in parallel to the known active antiplasmodial compounds present in those plants to assess how early in plant screening a potential mode of action can be hypothesized. Results show that extract effects can already be distinguished from a control, though fractions with active compounds separate more clearly. The more purified the fraction, the bigger the correlation in mode of action with the isolated natural compounds, possibly due to the lack of matrix effects and interactions, which shows that metabolomics can be introduced early in bioassay-guided fractionation in plant studies. Second, two of the most important plants in traditional medicine against malaria were studied, Artemisia afra and A. annua, to investigate their phenolic content, presence or absence of artemisinin and correlate the composition with the metabolomic results on a synchronized malaria culture. Results indicate a correlation between activity and artemisinin abundance in these extracts, with A. annua presenting a similar parasitic profile to artemisinin whereas A. afra, despite trace amounts of this compound, differs significantly. A. afra affects various unspecific metabolites but significantly changes myo-inositol distinctly from A. annua and artemisinin, which clearly target redox mechanisms. Lastly, three independent studies aimed to investigate three natural scaffolds for their mode of action: alkyl cyclohexenones compounds named poupartones, ellagic acid and derivatives, and a mixture of triterpene esters. Poupartones showed to interfere with hemoglobin metabolism, DNA and RNA synthesis and redox management systems which correlated to their potential to participate in nucleophilic additions that establish covalent bonds with proteins and generate radical oxygen species, an effective yet not specific type of activity. Our studies on ellagic acid and derivatives support literature data and point to the parasite’s digestive vacuole as the site of action of these compounds. Changes in hemoglobin metabolism and redox metabolites suggest possible effects on plasmepsins, enzymes that act early in hemoglobin breakdown, and on glutathione metabolism, essential to maintaining a balanced organelle. Lastly, a mixture of 8 triterpenic esters seems to affect pyrimidine synthesis and amino acid metabolism through N-carbamoyl-L-aspartate, though it is unclear exactly how. Metabolomics is a hypothesis generating approach that gives a snapshot of the effects of innovative natural compounds on the malaria parasite in order to accurately guide antimalarial drug discovery.METNATPA

La participación de las mujeres con cáncer de mama en el momento de escoger el tratamiento: un derecho a ser conquistado

The purpose of this study was to identify how women with breast cancer perceive themselves as subjects in the process of making decisions on their own treatment. Two objectives were pursued: (a) to identify social and political determinants that, by affecting the socialization process of these women, might have influenced them in adopting a style of participation, and (b) to understand the meaning of such participation, as it was perceived by these women at the time they decided on their treatment options. The theoretical-methodological support adopted was that of Symbolic Interactionism. The population sample included nine women with breast cancer. Semi-structured interviews allowed data to be gathered, and led to collecting further field notes and data from medical records. The hermeneutic dialectic method was employed as a compass for data interpretation, which made it possible to identify two broad theme units: 'construction of the female identity' and 'style of participation when choosing one's own treatment'. By means of these units it was possible to grasp what it meant for these women to deal with the issue of limits and, therefore, of ethics. In their view, they did not participate in the decision-making process, being regarded as unqualified to decide on the fate of their own bodies and lives. They were thus seen as obedient subjects in relation to medical decisions that are based on the principle of beneficence, where health care delivery is dependent on hierarchical social relationships and power structures are present between classes, genders, and levels of knowledge.Esta investigación pretendió identificar como las mujeres con cáncer de mama se perciben en cuanto sujetos en el proceso de tomar decisiones sobre su tratamiento. Los objetivos fueron: identificar determinantes sociales, económicos y políticos presentes en el proceso de socialización de estas mujeres que contribuyeron para la adopción de un estilo de participar y comprender el significado de la participación, tal como fue percibido por ellas en el momento, de decidir sobre su tratamiento. La fundamentación teórica metodológica fue inspirada en el Interaccionalismo Simbólico. La muestra constó de nueve mujeres con cáncer de mama. La entrevista semi-estructurada condujo la recolección de datos, así como, las anotaciones de campo y datos de la historia clínica. Tomándose la dialéctica hermenéutica como el camino del pensamiento interpretativo de los datos, fue posible identificar dos grandes unidades temáticas: 'construcción de la identidad' y 'estilo de participación en el momento de escoger el tratamiento', las cuales permitieron aprender que significó para ellas hablar de limitaciones y por tanto, de ética. Ellas interpretaron que no participaron del proceso de tomar decisiones por ser consideradas descalificadas para decidir sobre sus cuerpos y sus vidas, por tanto, un sujeto de obediencia a la decisión medica, que se fundamenta en el principio de la beneficencia, donde la atención a la salud se estructura a través de las relaciones sociales jerarquizadas, cuyas relaciones de poder se dan entre clases, géneros y saberes.Esta pesquisa pretendeu identificar como as mulheres com câncer de mama se percebem enquanto sujeitos no processo de tomada de decisão sobre seu tratamento. Os objetivos foram: identificar determinantes sociais e políticos presentes no processo de socialização dessas mulheres que contribuíram para a adoção de um estilo de participar, e compreender o significado da participação tal como foi percebido por elas no momento de decidirem sobre seu tratamento. A fundamentação teórico-metodológica foi inspirada no Interacionismo Simbólico. A amostra constou de nove mulheres com câncer de mama. A entrevista semi-estruturada conduziu à coleta de dados, assim como as anotações de campo e os dados do prontuário. Tomando-se a dialética hermenêutica como caminho do pensamento interpretativo dos dados, foi possível apreender duas grandes unidades temáticas: 'construção da identidade feminina' e 'estilo de participação na escolha do tratamento', as quais nos permitiram apreender o que, para elas, significou falar de limites e, portanto, de ética. Elas interpretaram que não participaram do processo de tomada de decisão por serem consideradas desqualificadas para decidirem sobre seus corpos e suas vidas - portanto, como sujeitos de obediência à decisão médica, que se fundamenta no princípio da beneficência, sendo que atendimento à saúde se estrutura por meio de relações sociais hierarquizadas cujas relações de poder se dão entre classes, gêneros e saberes

Recent metabolomic developments for antimalarial drug discovery.

peer reviewedMalaria is a parasitic disease that remains a global health issue, responsible for a significant death and morbidity toll. Various factors have impacted the use and delayed the development of antimalarial therapies, such as the associated financial cost and parasitic resistance. In order to discover new drugs and validate parasitic targets, a powerful omics tool, metabolomics, emerged as a reliable approach. However, as a fairly recent method in malaria, new findings are timely and original practices emerge frequently. This review aims to discuss recent research towards the development of new metabolomic methods in the context of uncovering antiplasmodial mechanisms of action in vitro and to point out innovative metabolic pathways that can revitalize the antimalarial pipeline

Secondary Metabolites Isolated from Artemisia afra and Artemisia annua and Their Anti-Malarial, Anti-Inflammatory and Immunomodulating Properties—Pharmacokinetics and Pharmacodynamics: A Review

peer reviewedThere are over 500 species of the genus Artemisia in the Asteraceae family distributed over the globe, with varying potentials to treat different ailments. Following the isolation of artemisinin (a potent anti-malarial compound with a sesquiterpene backbone) from Artemisia annua, the phytochemical composition of this species has been of interest over recent decades. Additionally, the number of phytochemical investigations of other species, including those of Artemisia afra in a search for new molecules with pharmacological potentials, has increased in recent years. This has led to the isolation of several compounds from both species, including a majority of monoterpenes, sesquiterpenes, and polyphenols with varying pharmacological activities. This review aims to discuss the most important compounds present in both plant species with anti-malarial properties, anti-inflammatory potentials, and immunomodulating properties, with an emphasis on their pharmacokinetics and pharmacodynamics properties. Additionally, the toxicity of both plants and their anti-malaria properties, including those of other species in the genus Artemisia, is discussed. As such, data were collected via a thorough literature search in web databases, such as ResearchGate, ScienceDirect, Google scholar, PubMed, Phytochemical and Ethnobotanical databases, up to 2022. A distinction was made between compounds involved in a direct anti-plasmodial activity and those expressing anti-inflammatory and immunomodulating activities or anti-fever properties. For pharmacokinetics activities, a distinction was made between compounds influencing bioavailability (CYP effect or P-Glycoprotein effect) and those affecting the stability of pharmacodynamic active components

Practice Inquiry: Clinical Uncertainty as a Focus for Small-Group Learning and Practice Improvement

PROBLEM: Many primary care physicians in nonacademic settings lack a collegial forum for engaging the clinical uncertainties inherent in their work. PROGRAM DESCRIPTION: “Practice Inquiry” is proposed as a set of small-group, practice-based learning and improvement (PBLI) methods designed to help clinicians better manage case-based clinical uncertainty. Clinicians meet regularly at their offices/clinics to present dilemma cases, share clinical experience, review evidence for blending with experience, and draw implications for practice improvement. From 2001 through 2005, Practice Inquiry was introduced to sites in the San Francisco Bay Area as a demonstration effort. Meeting rosters, case logs, a feedback survey, and meeting field notes documented implementation and provided data for a formative, qualitative evaluation. PROGRAM EVALUATION: Of the 30 sites approached, 14 held introductory meetings. As of summer 2006, 98 clinicians in 11 sites continue to hold regularly scheduled group meetings. Of the 118 patient cases presented in the seven oldest groups, clinician–patient relationship and treatment dilemmas were most common. Clinician feedback and meeting transcript data provided insights into how busy practitioners shared cases, developed trust, and learned new knowledge/skills for moving forward with patients. DISCUSSION: Ongoing clinician involvement suggests that Practice Inquiry is a feasible, acceptable, and potentially useful set of PBLI methods. Two of the Practice Inquiry’s group learning tasks received comparatively less focus: integrating research evidence with clinical experience and tracking dilemma case outcomes. Future work should focus on reducing the methodological limitations of a demonstration effort and examining factors affecting clinician participation. Set-aside work time for clinicians, or other equally potent incentives, will be necessary for the further elaboration of these PBLI methods aimed at managing uncertainty

Analysis of shared common genetic risk between amyotrophic lateral sclerosis and epilepsy

Because hyper-excitability has been shown to be a shared pathophysiological mechanism, we used the latest and largest genome-wide studies in amyotrophic lateral sclerosis (n = 36,052) and epilepsy (n = 38,349) to determine genetic overlap between these conditions. First, we showed no significant genetic correlation, also when binned on minor allele frequency. Second, we confirmed the absence of polygenic overlap using genomic risk score analysis. Finally, we did not identify pleiotropic variants in meta-analyses of the 2 diseases. Our findings indicate that amyotrophic lateral sclerosis and epilepsy do not share common genetic risk, showing that hyper-excitability in both disorders has distinct origins