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1.
Int J Integr Care ; 24(1): 19, 2024.
Article En | MEDLINE | ID: mdl-38525481

Introduction: Legal issues are known to affect and be affected by mental health. But to what extent do legal issues surface in mental health settings and what do staff feel they need to support clients experiencing these issues? These questions were explored by a national mental health service interested in the potential for health justice partnership with local community based legal services. Methods: A survey of 999 frontline staff of a national mental health organisation. 146 staff (15%) responded from 70 service sites across Australia, including peer support workers (47%), support workers (20%), team leaders (17%) and clinicians (15%). Results: Staff identified a wide range of legal issues experienced by their clients (commonly referred to by staff as consumers), most commonly credit, debt and social security issues, housing, family law and family violence. Two-thirds (67%) of respondents indicated that they spent around 50% or more of their time 'responding to these types of issues'. Respondents indicated that they need more support to address legal issues facing their clients, particularly more knowledge of other services, connections with professionals in other organisations and connections with community. They also felt they could benefit from additional processes, tools, and resources, and time to manage their case load. Originality: While there is an emerging field of research exploring the legal capability of citizens, this study explores what mental health service staff feel they need to support consumers experiencing legal issues that can interact with mental health.

2.
New Phytol ; 242(3): 1156-1171, 2024 May.
Article En | MEDLINE | ID: mdl-38513692

In Catharanthus roseus, monoterpenoid indole alkaloids (MIAs) are produced through the cooperation of four cell types, with final products accumulating in specialized cells known as idioblasts and laticifers. To explore the relationship between cellular differentiation and cell type-specific MIA metabolism, we analyzed the expression of MIA biosynthesis in germinating seeds. Embryos from immature and mature seeds were observed via stereomicroscopy, fluorescence microscopy, and electron microscopy. Time-series MIA and iridoid quantification, along with transcriptome analysis, were conducted to determine the initiation of MIA biosynthesis. In addition, the localization of MIAs was examined using alkaloid staining and imaging mass spectrometry (IMS). Laticifers were present in embryos before seed maturation. MIA biosynthesis commenced 12 h after germination. MIAs accumulated in laticifers of embryos following seed germination, and MIA metabolism is induced after germination in a tissue-specific manner. These findings suggest that cellular morphological differentiation precedes metabolic differentiation. Considering the well-known toxicity and defense role of MIAs in matured plants, MIAs may be an important defense strategy already in the delicate developmental phase of seed germination, and biosynthesis and accumulation of MIAs may require the tissue and cellular differentiation.


Catharanthus , Secologanin Tryptamine Alkaloids , Monoterpenes/metabolism , Catharanthus/metabolism , Germination , Seeds/metabolism , Secologanin Tryptamine Alkaloids/metabolism , Cell Differentiation , Plant Proteins/metabolism , Gene Expression Regulation, Plant
3.
Heliyon ; 10(6): e28078, 2024 Mar 30.
Article En | MEDLINE | ID: mdl-38533072

Specialized metabolites possess diverse interesting biological activities and some cardenolides- and monoterpene indole alkaloids- (MIAs) derived pharmaceuticals are currently used to treat human diseases such as cancers or hypertension. While these two families of biocompounds are produced by specific subfamilies of Apocynaceae, one member of this medicinal plant family, the succulent tree Pachypodium lamerei Drake (also known as Madagascar palm), does not produce such specialized metabolites. To explore the evolutionary paths that have led to the emergence and loss of cardenolide and MIA biosynthesis in Apocynaceae, we sequenced and assembled the P. lamerei genome by combining Oxford Nanopore Technologies long-reads and Illumina short-reads. Phylogenomics revealed that, among the Apocynaceae whose genomes have been sequenced, the Madagascar palm is so far the species closest to the common ancestor between MIA producers/non-MIA producers. Transposable elements, constituting 72.48% of the genome, emerge as potential key players in shaping genomic architecture and influencing specialized metabolic pathways. The absence of crucial MIA biosynthetic genes such as strictosidine synthase in P. lamerei and non-Rauvolfioideae species hints at a transposon-mediated mechanism behind gene loss. Phylogenetic analysis not only showcases the evolutionary divergence of specialized metabolite biosynthesis within Apocynaceae but also underscores the role of transposable elements in this intricate process. Moreover, we shed light on the low conservation of enzymes involved in the final stages of MIA biosynthesis in the distinct MIA-producing plant families, inferring independent gains of these specialized enzymes along the evolution of these medicinal plant clades. Overall, this study marks a leap forward in understanding the genomic dynamics underpinning the evolution of specialized metabolites biosynthesis in the Apocynaceae family, with transposons emerging as potential architects of genomics restructuring and gene loss.

4.
Proc Natl Acad Sci U S A ; 121(7): e2318586121, 2024 Feb 13.
Article En | MEDLINE | ID: mdl-38319969

Monoterpene indole alkaloids (MIAs) are a large and diverse class of plant natural products, and their biosynthetic construction has been a subject of intensive study for many years. The enzymatic basis for the production of aspidosperma and iboga alkaloids, which are produced exclusively by members of the Apocynaceae plant family, has recently been discovered. Three carboxylesterase (CXE)-like enzymes from Catharanthus roseus and Tabernanthe iboga catalyze regio- and enantiodivergent [4+2] cycloaddition reactions to generate the aspidosperma (tabersonine synthase, TS) and iboga (coronaridine synthase, CorS; catharanthine synthase, CS) scaffolds from a common biosynthetic intermediate. Here, we use a combined phylogenetic and biochemical approach to investigate the evolution and functional diversification of these cyclase enzymes. Through ancestral sequence reconstruction, we provide evidence for initial evolution of TS from an ancestral CXE followed by emergence of CorS in two separate lineages, leading in turn to CS exclusively in the Catharanthus genus. This progression from aspidosperma to iboga alkaloid biosynthesis is consistent with the chemotaxonomic distribution of these MIAs. We subsequently generate and test a panel of chimeras based on the ancestral cyclases to probe the molecular basis for differential cyclization activity. Finally, we show through partial heterologous reconstitution of tabersonine biosynthesis using non-pathway enzymes how aspidosperma alkaloids could have first appeared as "underground metabolites" via recruitment of promiscuous enzymes from common protein families. Our results provide insight into the evolution of biosynthetic enzymes and how new secondary metabolic pathways can emerge through small but important sequence changes following co-option of preexisting enzymatic functions.


Aspidosperma , Catharanthus , Secologanin Tryptamine Alkaloids , Tabernaemontana , Tabernaemontana/metabolism , Aspidosperma/metabolism , Carboxylesterase/metabolism , Phylogeny , Indole Alkaloids/metabolism , Secologanin Tryptamine Alkaloids/chemistry , Secologanin Tryptamine Alkaloids/metabolism , Plants/metabolism , Catharanthus/metabolism
5.
Can J Cardiol ; 2024 Feb 09.
Article En | MEDLINE | ID: mdl-38342292

BACKGROUND: Cardiometabolic diseases increase the risk of postoperative atrial fibrillation (POAF), a complication leading to higher long-term risk of major cardiovascular events (MACE). It remains unknown whether the effect of these risk factors differs according to sex. We sought to evaluate the sex-specific predictors of POAF after coronary artery bypass grafting (CABG). METHODS: In a prospective registry of patients undergoing isolated CABG, we compared predictors of POAF between sexes with logistic regression models. Because of high prevalence of abdominal obesity in women, > 80% having a waist circumference (WC) ≥ 88 cm, median WC values were used to define abdominal obesity (men ≥ 102 cm, women ≥ 100 cm). RESULTS: This analysis included 6177 individuals (17% women). Mean age was 65.6 ± 8.9 years. POAF occurred in 32% of men and 28% of women (P < 0.05). Compared with men, women with POAF had similar WC; higher prevalence of hypertension and diabetes; lower high-density lipoprotein (HDL)-cholesterol; and higher glucose, triglyceride, low- density lipoprotein (LDL)-cholesterol, and C-reactive protein levels (all P < 0.05). After adjustment, age and abdominal obesity were associated with POAF in both sexes (P < 0.05). The interaction of WC with sex suggested a worse impact of WC on POAF risk among women (adjusted odds ratio [OR], 1.97; 95% confidence interval [CI], 1.48-2.62 vs in men 1.33; 95% CI, 1.17-1.50; P for interaction = 0.01). CONCLUSIONS: Abdominal obesity is a major predictor of POAF in both sexes, with higher risk in women. These results emphasize the need for enhanced strategies to manage abdominal obesity and its cardiometabolic consequences in the general population and the potential to develop sex-specific preventive interventions to reduce risk of POAF.

6.
Neuropsychol Rev ; 34(1): 134-154, 2024 Mar.
Article En | MEDLINE | ID: mdl-36696021

Growing evidence points to a spectrum of non-motor symptoms, including cognitive difficulties that have a greater impact on functional outcomes and quality of life than motor symptoms in cervical dystonia (CD). Some cognitive impairments have been reported; however, findings are inconsistent, and described across mixed groups of dystonia. The current review aimed to examine the evidence for cognitive impairments in CD. MEDLINE, EMBASE, PsychINFO and Web of Science databases were searched. Studies were included if they met the following criteria (i) cross-sectional or longitudinal studies of adults with CD, (ii) where the results of standardised measures of cognitive or neuropsychological function in any form were assessed and reported, (iii) results compared to a control group or normative data, and (iv) were published in English. Results are presented in a narrative synthesis. Twenty studies were included. Subtle difficulties with general intellectual functioning, processing speed, verbal memory, visual memory, visuospatial function, executive function, and social cognition were identified while language, and attention and working memory appear to be relatively spared. Several methodological limitations were identified that should be considered when interpreting the evidence to describe a specific profile of cognitive impairment in CD. Clinical and research implications are discussed.


Torticollis , Adult , Humans , Quality of Life , Cross-Sectional Studies , Cognition , Memory, Short-Term
8.
Appl Physiol Nutr Metab ; 49(2): 179-189, 2024 Feb 01.
Article En | MEDLINE | ID: mdl-37820379

The long-term consequences of COVID-19 on healthy behaviours (physical activity practice and healthy eating) among Canadians remain largely unexplored. The objectives were (i) to describe the proportion of Canadians who reported a change in healthy behaviours, 9 and 20 months since the beginning of COVID-19; and (ii) to identify the social determinants associated with healthy behaviour changes. Using two representative Canadian surveys from the International COVID-19 Awareness and Responses Evaluation study (January 2021, n = 3000; November 2021, n = 3002), reported changes in healthy behaviours were assessed as follows: "In general, how have the following behaviours changed since the start of COVID-19?": (1) Increase; (2) No change; and (3) Decrease. The association between individual determinants and changes in healthy behaviours was analyzed using weighted univariate polytomous logistic regression models. In January 2021, 41% and 22% of respondents reported a decline in physical activity and healthy eating, respectively, while in November 2021, 34% and 20% of respondents reported a decline in physical activity and healthy eating, respectively. The main determinants associated with changes in healthy behaviours were younger age (18-25 years), area of residency, student status, changes in bodyweight, financial concerns/insecurity, anxiety/depression, and ethnicity. Changes in healthy behaviours were also associated with household composition, presence of chronic diseases, and occupation. In sum, this study depicted long-term changes in healthy behaviours during COVID-19, with differential changes according to social determinants of health. This study highlighted the presence of health inequalities in Canada during COVID-19 and supports the implementation of personalized programs in prevention of healthy behaviour degradation.


COVID-19 , North American People , Humans , Adolescent , Young Adult , Adult , COVID-19/epidemiology , COVID-19/prevention & control , Cross-Sectional Studies , Diet, Healthy , Pandemics , Social Determinants of Health , Canada/epidemiology , Sedentary Behavior , Exercise , Surveys and Questionnaires
9.
Appl Physiol Nutr Metab ; 49(3): 350-359, 2024 Mar 01.
Article En | MEDLINE | ID: mdl-37939366

To evaluate the effects of high dairy (HD) (≥4 servings/day), compared to adequate dairy (AD) (2-3 servings/day as per Canada's Food Guide for Healthy Eating (2007)), on blood pressure (BP) and measures of arterial stiffness in hyperinsulinemic subjects. In this cross-over clinical trial, hyperinsulinemic adults were randomized to AD and HD for 6 weeks. Anthropometric, glycemic, and lipid parameters were analyzed and dietary intake was evaluated; BP, carotid-femoral pulse wave velocity, augmentation index, and measures of arterial stiffness were assessed. Twenty-seven participants completed the study. Dairy intake was 2.2 ± 1.2 servings/day during AD. In addition, lower total and low-density lipoprotein (LDL) cholesterol were observed without significant change in BP or arterial stiffness between before and after AD. During HD, the subjects consumed 5.8 ± 1.9 servings/day of dairy products, providing a higher intake of protein, saturated fat, calcium, phosphorus, sodium, and potassium compared to the baseline diet. After the HD, subjects had higher body fat, fasting insulin, homeostatic model assessment for insulin resistance (HOMA-IR) index, and triglycerides without altering BP or arterial stiffness compared to before HD. Overall, adequate or high intake of total dairy did not modify BP or arterial stiffness in hyperinsulinemic adults after 6 weeks.


Vascular Stiffness , Adult , Humans , Blood Pressure , Pulse Wave Analysis , Insulin , Pressure
10.
Plant Physiol ; 194(4): 2580-2599, 2024 Mar 29.
Article En | MEDLINE | ID: mdl-38101922

Triterpenes are a class of bioactive compounds with diverse biological functions, playing pivotal roles in plant defense against biotic stressors. Oxidosqualene cyclases (OSCs) serve as gatekeepers in the biosynthesis of triterpenes. In this study, we utilized a Nicotiana benthamiana heterologous expression system to characterize NaOSC1 from Nicotiana attenuata as a multifunctional enzyme capable of synthesizing lupeol, dammarenediol II, 3-alpha,20-lupanediol, and 7 other triterpene scaffolds. We also demonstrated that NaOSC2 is, in contrast, a selective enzyme, producing only the ß-amyrin scaffold. Through virus-induced gene silencing and in vitro toxicity assays, we elucidated the roles of NaOSC1 and NaOSC2 in the defense of N. attenuata against Manduca sexta larvae. Metabolomic and feature-based molecular network analyses of leaves with silenced NaOSC1 and NaOSC2 unveiled 3 potential triterpene glycoside metabolite clusters. Interestingly, features identified as triterpenes within these clusters displayed a significant negative correlation with larval mass. Our study highlights the pivotal roles of NaOSC1 and NaOSC2 from N. attenuata in the initial steps of triterpene biosynthesis, subsequently influencing defense against M. sexta through the modulation of downstream triterpene glycoside compounds.


Intramolecular Transferases , Manduca , Triterpenes , Animals , Nicotiana/genetics , Triterpenes/metabolism , Pentacyclic Triterpenes , Intramolecular Transferases/genetics , Intramolecular Transferases/metabolism , Larva/metabolism
12.
Article En | MEDLINE | ID: mdl-38140980

Monoterpene indole alkaloids (MIAs) are a class of natural products comprised of thousands of structurally unique bioactive compounds with significant therapeutic values. Due to difficulties associated with isolation from native plant species and organic synthesis of these structurally complex molecules, microbial production of MIAs using engineered hosts are highly desired. In this work, we report the engineering of fully integrated Saccharomyces cerevisiae strains that allow de novo access to strictosidine, the universal precursor to thousands of MIAs at 30-40 mg/L. The optimization efforts were based on a previously reported yeast strain that is engineered to produce high titers of the monoterpene precursor geraniol through compartmentalization of mevalonate pathway in the mitochondria. Our approaches here included the use of CRISPR-dCas9 interference to identify mitochondria diphosphate transporters that negatively impact the titer of the monoterpene, followed by genetic inactivation; the overexpression of transcriptional regulators that increase cellular respiration and mitochondria biogenesis. Strain construction included the strategic integration of genes encoding both MIA biosynthetic and accessory enzymes into the genome under a variety of constitutive and inducible promoters. Following successful de novo production of strictosidine, complex alkaloids belonging to heteroyohimbine and corynantheine families were reconstituted in the host with introduction of additional downstream enzymes. We demonstrate that the serpentine/alstonine pair can be produced at ∼5 mg/L titer, while corynantheidine, the precursor to mitragynine can be produced at ∼1 mg/L titer. Feeding of halogenated tryptamine led to the biosynthesis of analogs of alkaloids in both families. Collectively, our yeast strain represents an excellent starting point to further engineer biosynthetic bottlenecks in this pathway and to access additional MIAs and analogs through microbial fermentation. ONE SENTENCE SUMMARY: An Saccharomyces cerevisiae-based microbial platform was developed for the biosynthesis of monoterpene indole alkaloids, including the universal precursor strictosidine and further modified heteroyohimbine and corynantheidine alkaloids.


Saccharomyces cerevisiae , Secologanin Tryptamine Alkaloids , Humans , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Secologanin Tryptamine Alkaloids/metabolism , Monoterpenes/metabolism , Plants/metabolism , Metabolic Engineering
13.
Womens Health Rep (New Rochelle) ; 4(1): 584-593, 2023.
Article En | MEDLINE | ID: mdl-38099076

Background: Approximately one in every eight mothers experience symptoms of postpartum depression (PPD) in the United States.1 Existing literature lacks an in-depth exploration of the social context from which symptoms of PPD arise. The objectives of this study were to (1) determine the prevalence of postpartum depressive symptoms (PDS) among new mothers and to explore relationships between selected social determinants of health (SDOH) and the likelihood of experiencing PDS. Materials and Methods: Data were from the Pregnancy Risk Assessment Monitoring System (PRAMS) 2016 and 2017 Questionnaires. Measured SDOH included socioeconomic status, social network support, psychosocial stress, and availability of resources to meet basic daily needs. Outcome measurement included a combination of two symptom indicator questions. Univariate analyses yielded weighted frequencies of descriptive statistics according to PDS status, and bivariate and multivariate logistic regression analyses yielded odds of reporting PDS. Results: The prevalence of self-reported PDS was 3.5%. Among mothers with PDS, most (54%) lived at or below the federal poverty guideline. Mothers who experienced psychosocial stress (e.g., intimate partner violence) during pregnancy had the highest likelihood of reporting PDS (adjusted odds ratio [aOR] = 3.60; confidence interval [95% CI], 2.12-6.12). Mothers who considered their most recent pregnancy unintended or mistimed were more likely to report PDS (aOR = 1.36; 95% CI, 1.01-1.82), (aOR = 1.65; 95% CI, 1.19-2.27), respectively. Conclusion: Results demonstrate that several social and psychosocial risk factors significantly impact the likelihood of experiencing PDS. The risk of PDS was particularly significant among lower socioeconomic status mothers, especially those with inadequate social network support. Public health efforts to mitigate potentially harmful social factors should focus on transforming public policies and social programs and increasing screening opportunities.

14.
Commun Biol ; 6(1): 1197, 2023 11 24.
Article En | MEDLINE | ID: mdl-38001233

Monoterpene indole alkaloids (MIAs) are a structurally diverse family of specialized metabolites mainly produced in Gentianales to cope with environmental challenges. Due to their pharmacological properties, the biosynthetic modalities of several MIA types have been elucidated but not that of the yohimbanes. Here, we combine metabolomics, proteomics, transcriptomics and genome sequencing of Rauvolfia tetraphylla with machine learning to discover the unexpected multiple actors of this natural product synthesis. We identify a medium chain dehydrogenase/reductase (MDR) that produces a mixture of four diastereomers of yohimbanes including the well-known yohimbine and rauwolscine. In addition to this multifunctional yohimbane synthase (YOS), an MDR synthesizing mainly heteroyohimbanes and the short chain dehydrogenase vitrosamine synthase also display a yohimbane synthase side activity. Lastly, we establish that the combination of geissoschizine synthase with at least three other MDRs also produces a yohimbane mixture thus shedding light on the complex mechanisms evolved for the synthesis of these plant bioactives.


Rauwolfia , Rauwolfia/genetics , Rauwolfia/metabolism , Monoterpenes , Indole Alkaloids/metabolism
15.
Nat Chem Biol ; 19(12): 1551-1560, 2023 Dec.
Article En | MEDLINE | ID: mdl-37932529

Monoterpenoid indole alkaloids (MIAs) represent a large class of plant natural products with marketed pharmaceutical activities against a wide range of indications, including cancer, malaria and hypertension. Halogenated MIAs have shown improved pharmaceutical properties; however, synthesis of new-to-nature halogenated MIAs remains a challenge. Here we demonstrate a platform for de novo biosynthesis of two MIAs, serpentine and alstonine, in baker's yeast Saccharomyces cerevisiae and deploy it to systematically explore the biocatalytic potential of refactored MIA pathways for the production of halogenated MIAs. From this, we demonstrate conversion of individual haloindole derivatives to a total of 19 different new-to-nature haloserpentine and haloalstonine analogs. Furthermore, by process optimization and heterologous expression of a modified halogenase in the microbial MIA platform, we document de novo halogenation and biosynthesis of chloroalstonine. Together, this study highlights a microbial platform for enzymatic exploration and production of complex natural and new-to-nature MIAs with therapeutic potential.


Catharanthus , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Monoterpenes/metabolism , Indole Alkaloids/metabolism , Plants/metabolism , Pharmaceutical Preparations/metabolism , Plant Proteins/metabolism
16.
J Addict Med ; 17(6): 702-707, 2023.
Article En | MEDLINE | ID: mdl-37934535

OBJECTIVES: To study clinician perspectives on the feasibility of incorporating family planning services within office-based addiction treatment (OBAT) clinics. We sought to understand the unique facilitators of and barriers to the integration of contraceptive services within the OBAT model with a goal to support the design and implementation of a program tailored to meet the reproductive health needs of patients with substance use disorder. METHODS: After obtaining institutional review board approval, we conducted qualitative semistructured interviews with OBAT clinicians (registered nurses, advanced practice registered nurses, and physicians) at a tertiary-care safety-net hospital. Interview transcripts were analyzed using deductive codes utilizing key components of the Promoting Action on Research Implementation in Health Services and Ottawa Decision Support Frameworks. RESULTS: We analyzed 20 interviews. Our data noted 3 major themes: (1) evidence to support integration of family planning and OBAT, (2) inherent strengths and facilitative factors of the OBAT model, and (3) barriers and challenges of the OBAT model influencing successful integration. Strengths included the destigmatizing and trust-building OBAT approach to care, common use of patient-centered counseling, and providers' nuanced understanding of substance use disorder-specific impacts on reproductive health. Barriers included time constraints, balancing urgent patient recovery needs, the desire for additional contraception provision training, and concern for potential contraceptive coercion. CONCLUSIONS: Office-based addiction treatment clinics have inherent strengths that may make it a beneficial location for integrated family planning services. Future research should elicit patient perspectives to ensure the implementation of a family planning program in OBAT that supports patients' reproductive goals while avoiding stigma or reproductive coercion.


Behavior, Addictive , Substance-Related Disorders , Humans , Family Planning Services , Contraceptive Agents , Contraception
17.
MedEdPORTAL ; 19: 11350, 2023.
Article En | MEDLINE | ID: mdl-37822302

Introduction: Medical students lack systematic exposure to community engagement. Community-engaged research (CEnR) is an effective approach to improve community health, and community-engaged physicians are better attuned to the community context of their patients' health and well-being. The Medical College of Wisconsin (MCW) Office of Community Engagement began offering the educational series Foundations of Community Engagement in 2021 to meet this need. Methods: We developed and implemented a four-session series for medical students at MCW and the University of Nebraska Medical Center. A 1-hour session on the foundations of CEnR was held for all learners. Three 1-hour sessions dove deeper into CEnR principles for a self-selected cohort. These small-group sessions involved discussion between faculty and community partners and facilitated small-group discussion. Students completed evaluations after each session. Results: A total of 160 students participated in the introductory session; 36 took part in the follow-up series. Survey response rates varied from 38% to 67% for each session. Overall, 87% of students in all sessions felt their session was worthwhile, with 85% of large-group and 96% of small-group respondents reporting they learned something they would use in their practice or profession. Qualitative responses included appreciation for addressing a curricular gap and desire for more time and more sessions to continue discussions. Discussion: The program was effective at stimulating medical student self-reported gains in skills, attitudes, and future intentions regarding CEnR in an efficient manner. Effective programs that transfer positive CEnR skills and attitudes to future physicians can promote CEnR within academic medicine.


Community Participation , Education, Medical, Undergraduate , Physicians , Public Health , Students, Medical , Humans , Faculty , Learning , Wisconsin
18.
Proc Natl Acad Sci U S A ; 120(42): e2307981120, 2023 10 17.
Article En | MEDLINE | ID: mdl-37812727

Benzoxazinoids (BXDs) form a class of indole-derived specialized plant metabolites with broad antimicrobial and antifeedant properties. Unlike most specialized metabolites, which are typically lineage-specific, BXDs occur sporadically in a number of distantly related plant orders. This observation suggests that BXD biosynthesis arose independently numerous times in the plant kingdom. However, although decades of research in the grasses have led to the elucidation of the BXD pathway in the monocots, the biosynthesis of BXDs in eudicots is unknown. Here, we used a metabolomic and transcriptomic-guided approach, in combination with pathway reconstitution in Nicotiana benthamiana, to identify and characterize the BXD biosynthetic pathways from both Aphelandra squarrosa and Lamium galeobdolon, two phylogenetically distant eudicot species. We show that BXD biosynthesis in A. squarrosa and L. galeobdolon utilize a dual-function flavin-containing monooxygenase in place of two distinct cytochrome P450s, as is the case in the grasses. In addition, we identified evolutionarily unrelated cytochrome P450s, a 2-oxoglutarate-dependent dioxygenase, a UDP-glucosyltransferase, and a methyltransferase that were also recruited into these BXD biosynthetic pathways. Our findings constitute the discovery of BXD pathways in eudicots. Moreover, the biosynthetic enzymes of these pathways clearly demonstrate that BXDs independently arose in the plant kingdom at least three times. The heterogeneous pool of identified BXD enzymes represents a remarkable example of metabolic plasticity, in which BXDs are synthesized according to a similar chemical logic, but with an entirely different set of metabolic enzymes.


Magnoliopsida , Magnoliopsida/metabolism , Benzoxazines/metabolism , Poaceae/metabolism , Metabolic Networks and Pathways/genetics , Plants/metabolism , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism
19.
Nat Plants ; 9(10): 1607-1617, 2023 10.
Article En | MEDLINE | ID: mdl-37723202

Cardenolides are specialized, steroidal metabolites produced in a wide array of plant families1,2. Cardenolides play protective roles in plants, but these molecules, including digoxin from foxglove (Digitalis spp.), are better known for treatment of congenital heart failure, atrial arrhythmia, various cancers and other chronic diseases3-9. However, it is still unknown how plants synthesize 'high-value', complex cardenolide structures from, presumably, a sterol precursor. Here we identify two cytochrome P450, family 87, subfamily A (CYP87A) enzymes that act on both cholesterol and phytosterols (campesterol and ß-sitosterol) to form pregnenolone, the first committed step in cardenolide biosynthesis in the two phylogenetically distant plants Digitalis purpurea and Calotropis procera. Arabidopsis plants overexpressing these CYP87A enzymes ectopically accumulated pregnenolone, whereas silencing of CYP87A in D. purpurea leaves by RNA interference resulted in substantial reduction of pregnenolone and cardenolides. Our work uncovers the key entry point to the cardenolide pathway, and expands the toolbox for sustainable production of high-value plant steroids via synthetic biology.


Cardenolides , Digitalis , Cardenolides/metabolism , Plants/metabolism , Digitalis/chemistry , Digitalis/metabolism , Pregnenolone
20.
Breastfeed Med ; 18(9): 645-665, 2023 09.
Article En | MEDLINE | ID: mdl-37672571

Background: Postpartum contraceptive use can help prevent short-interval pregnancies, which have been associated with adverse neonatal and maternal health outcomes. Many contraceptive methods are safe for postpartum use, but patients and providers may be confused as to what impact hormonal contraception has on lactation. We performed a scoping review of the most recent U.S.-based guidelines regarding hormonal contraception on lactation to provide synthesis and recommendations to aid providers in counseling their patients. Methods: We conducted a scoping review by identifying the most recent clinical recommendations and guidelines from the Centers for Disease Control and Prevention (CDC) and three maternal and child health professional associations (American College of Obstetricians and Gynecologists [ACOG], Society for Maternal-Fetal Medicine [SMFM], and Academy of Breastfeeding Medicine [ABM]). We also reviewed the citations in these guidelines used in their development. We then conducted an updated literature review to capture studies published since the most recent systematic reviews were conducted. Results: We reviewed 1 clinical guideline from the CDC and 2 systematic reviews cited in its references, 6 professional association recommendations, and 28 publications identified through the updated literature review. Progestin-only contraceptive methods continue to demonstrate safety in breastfeeding patients, while low-quality evidence supports concerns of decreased milk supply with combined hormonal contraception. Discussion: Organizations should consider updating counseling recommendations regarding progestin-only contraceptives and lactation. Further research is needed to examine new contraceptive methods as well as the effect of hormonal contraception on lactation in the setting of preterm birth.


Breast Feeding , Premature Birth , Infant, Newborn , United States , Child , Female , Pregnancy , Humans , Hormonal Contraception , Progestins , Lactation
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