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Background: Cannabis use suppresses the endocannabinoid system in healthy individuals. However, the association between cannabis use with the endocannabinoid system is understudied in individuals with psychosis despite the high rate of cannabis use in these individuals. Methods: We enrolled 83 individuals who were admitted to an inpatient psychiatric unit with psychotic presentations, and measured their plasma levels of main endocannabinoids, Anandamide (AEA) and 2-Acylglycerol (2-AG), and endocannabinoid related compounds, Palmitoylethanolamine, and N-oleoylethanolamine. Cannabis use was assessed with urine toxicology and frequency of cannabis use was assessed using self-reported questionnaires. The Positive and Negative Syndrome Scale was used to assess the severity of psychotic symptoms. Results: Overall, we had 38 individuals in cannabis positive group (CN+) and 45 individuals in cannabis negative group (CN−). Compared to CN−, CN+ group had lower plasma levels of AEA, which remained significant after controlling for age, gender, race/ethnicity, and use of other drugs. Conclusion: Cannabis use is associated with low plasma AEA levels in individuals with psychosis, which is in the same line with reported suppressive effects of cannabis on the endocannabinoid system in healthy individuals. Further studies are needed to investigate the clinical significance of this finding.

The antimicrobial resistance crisis requires the introduction of novel antibiotics. The use of conventional broad-spectrum compounds selects for resistance in off-target pathogens and harms the microbiome. This is especially true for Mycobacterium tuberculosis, where treatment requires a 6-month course of antibiotics. Here we show that a novel antimicrobial from Photorhabdus noenieputensis, which we named evybactin, is a potent and selective antibiotic acting against M. tuberculosis. Evybactin targets DNA gyrase and binds to a site overlapping with synthetic thiophene poisons. Given the conserved nature of DNA gyrase, the observed selectivity against M. tuberculosis is puzzling. We found that evybactin is smuggled into the cell by a promiscuous transporter of hydrophilic compounds, BacA. Evybactin is the first, but likely not the only, antimicrobial compound found to employ this unusual mechanism of selectivity.

Background: Cyclin-dependent kinase 4/6 inhibitors (CKD4/6i) have demonstrated clinical utility extending progression-free survival (PFS) and overall survival (OS) for advanced hormone receptor positive and HER2 negative (HR+/HER2-) breast cancer patients. The efficacy in early-stage breast cancer (eBC) is unclear, with conflicting results from adjuvant CDK4/6i trials on invasive disease-free survival. Thus, there is a critical need to identify biomarkers of response (BoR) to determine which, if any, eBC patients could benefit from this treatment. This BoR could also stratify advanced BC patients for likelihood to respond to CDK4/6i. Metabolism is influenced by both genome and environment, and changes in the metabolome can be correlated with drug responsiveness. Thus, metabolite BoRs may serve to identify eBC patients for which CDK4/6i would offer a therapeutic benefit.Methods: Plasma and serum samples from 50 early-stage ER+/HER2- breast cancer patients, treated with neoadjuvant CDK4/6 inhibitor palbociclib (palbo) and aromatase inhibitor (AI) anastrozole on NeoPalAna trial (ClinicalTrials.gov identifier NCT01723774), were collected from treatment-naïve patients (BL) and 3 consecutive time points: anastrozole,1 mg daily for 4 weeks (C1D1), anastrozole plus palbo,125 mg daily, for 15 days (C1D15), and for 4-5 months before surgery (SURG). Metabolites were extracted from all samples via methanol and chloroform precipitation and quantified using an unbiased, non-destructive, nuclear magnetic resonance (NMR)-based profiling platform (Olaris®, Inc., Waltham, MA). Statistical analysis and machine learning was used to identify differential metabolites and generate predictive models. A separate validation set of samples was collected from a subset of patients (N=6) who received an additional cycle of palbo treatment prior to surgery to assess model accuracy. Results: Non-parametric differential expression analysis of BL/C1D1, BL/C1D15, and C1D1/C1D15 identified 53 ,97, and 90 differential NMR resonances in plasma (p2.7%). Analysis of the responder (R) and non-responder (NR) groups identified that 13 plasma and 14 serum resonances (21 unique resonances and 6 overlapping) were differentially expressed (p Citation Format: Chen Dong, Shana Thomas, Chandrashekhar Honrao, Leonardo O. Rodrigues, Nathalie Tessier, Bo Zhang, Souzan Sanati, Kiran Vij, Brenda J. Ernst, Karen S. Anderson, Mateusz Opyrchal, Foluso Ademuyiwa, Lindsay L. Peterson, Matthew P. Goetz, Donald Northfelt, Elizabeth O'Day, Cynthia Ma. Identifying a metabolite signature that correlates with tumor proliferation in early-stage breast cancer patients treated with CDK4/6 inhibitors from matched plasma and serum samples [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-13-20.

The current need for novel antibiotics is especially acute for drug-resistant Gram-negative pathogens1,2. These microorganisms have a highly restrictive permeability barrier, which limits the penetration of most compounds3,4. As a result, the last class of antibiotics that acted against Gram-negative bacteria was developed in the 1960s2. We reason that useful compounds can be found in bacteria that share similar requirements for antibiotics with humans, and focus on Photorhabdus symbionts of entomopathogenic nematode microbiomes. Here we report a new antibiotic that we name darobactin, which was obtained using a screen of Photorhabdus isolates. Darobactin is coded by a silent operon with little production under laboratory conditions, and is ribosomally synthesized. Darobactin has an unusual structure with two fused rings that form post-translationally. The compound is active against important Gram-negative pathogens both in vitro and in animal models of infection. Mutants that are resistant to darobactin map to BamA, an essential chaperone and translocator that folds outer membrane proteins. Our study suggests that bacterial symbionts of animals contain antibiotics that are particularly suitable for development into therapeutics.

Background: CDK4/6 inhibitors (CDK4/6i) palbociclib (palbo) and abemaciclib (abema) have significantly improved outcomes in patients with hormonal receptor positive (HR+)/human epidermal growth factor receptor negative (HER2-) breast cancer. Yet almost 20% of patients never respond to treatment and all patients eventually develop acquired resistance. In vitro palbo and abema have different affinities for CDK4/6 and other cellular kinases, and in vivo they have different toxicity profiles. At present there are no clinically validated biomarkers to determine CDK4/6i sensitivity or resistance. Further it is not clear if and how to choose between the CDK4/6i for optimal outcomes. In this study, using 13C-isotopically enriched glucose we sought to identify metabolic changes associated with palbo and abema treatment in sensitive and resistant cell lines. Methods: MCF-7 cells (wild-type), palbociclib resistant cells (PDR) and abemaciclib resistant cells (ABR) treated with DMSO, palbo or abema were incubated for 24hrs in DMEM supplemented with 13C-glucose. After the incubation, cells were harvested, metabolites were extracted and analyzed via 1D and 2D NMR spectroscopy. Biological triplicates were prepared for each condition. Results: In wild-type MCF-7 cells treated with palbo or abema significant metabolite changes were observed compared to DMSO. In both palbo and abema treatment a marked decrease in nucleotide metabolites was observed, which is consistent with the ability of CDK4/6i to prevent cell cycle progression. In abema treated cells there was also significant decrease in metabolites involved in the serine-glycine pathway, which was not observed in the palbo treated cells. Palbo and abema treated cells were easily distinguishable via hierarchical clustering. PDR and ABR also had distinct metabolic profiles when they were maintained with palbo and abema, respectively or if the drugs were removed. Notably the serine-glycine pathway was increased in ABR cells but decreased in PDR cells. In PDR cells we observed an increase in glucose-1-phosphate and shift towards galactose/glycogen metabolism. Conclusions: Using cell line models we were able to demonstrate that glucose metabolism is altered in palbo and abema treatment and that resistance to each drug may activate different metabolic pathways. To the best of our knowledge this is the first direct evidence of palbo-specific and abema-specific metabolite signatures. We are assessing whether the results of these in vitro studies translate to clinical samples. If so, the altered metabolites could lead to biomarkers that correlate with response and resistance for specific CDK4/6i. Further, we are exploring if by targeting the pathways associated with resistance, we can restore CDK4/6i sensitivity. This could lead to novel therapeutic targets or treatment regimens that improve patient outcomes. Citation Format: Chandrashekhar Honrao, Kanchan Sonkar, Cristina Guarducci, Agostina Nardone, Wen Ma, Srihari Raghavendra Rao, Chen Dong, Leo Rodrigues, Rinath Jeselsohn, Elizabeth O'Day. Isotopic tracing reveals distinct metabolic changes with palbociclib or abemaciclib treatment & resistance in breast cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5802.

New oximes short-acting CB1 agonists were explored by the introduction of an internal oxime and polar groups at the C3 alkyl tail of Δ8-THC. The scope of the research was to drastically alter two important physicochemical properties hydrophobicity (log P) and topological surface area (tPSA) of the compound, which play a critical role in tissue distribution and sequestration (depot effect). Key synthesized analogs demonstrated sub-nanomolar affinity for CB1, marked reduction in hydrophobicity (ClogP∼2.5–3.5 vs 9.09 of Δ8-THC-DMH), and found to function as either agonists (trans-oximes) or neutral antagonists (cis-oximes) in a cAMP functional assay. All oxime analogs showed comparable affinity at the CB2 receptor, but surprisingly they were found to function as inverse agonists for CB2. In behavioral studies (i.e. analgesia, hypothermia) trans-oxime 8a exhibited a predictable fast onset (∼20 min) and short duration of pharmacological action (∼180 min), in contrast to the very prolonged duration of Δ8-THC-DMH (>24 h), thus limiting the potential for severe psychotropic side-effects associated with persistent activation of the CB1 receptor. We have conducted 100 ns molecular dynamic (MD) simulations of CB1 complexes with AM11542 (CB1 agonist) and both trans-8a and cis-8b isomeric oximes. These studies revealed that the C3 alkyl tail of cis-8b orientated within the CB1 binding pocket in a manner that triggered a conformational change that stabilized the CB1 receptor at its inactive-state (antagonistic functional effect). In contrast, the trans-8a isomer’s conformation was coincided with that of the AM11542 CB1 agonist-bound structure, stabilizing the CB1 receptor at the active-state (agonistic functional effect). We have selected oxime trans-8a based on its potency for CB1, and favorable pharmacodynamic profile, such as fast onset and predictable duration of pharmacological action, for evaluation in pre-clinical models of anorexia nervosa.

The synthesis of potent metabolically stable endocannabinoids is challenging. Here we report a chiral arachidonoyl ethanolamide (AEA) analogue, namely, (13S,1′R)-dimethylanandamide (AMG315, 3a), a high affinity ligand for the CB1 receptor (Ki of 7.8 ± 1.4 nM) that behaves as a potent CB1 agonist in vitro (EC50 = 0.6 ± 0.2 nM). (13S,1′R)-dimethylanandamide is the first potent AEA analogue with significant stability for all endocannabinoid hydrolyzing enzymes as well as the oxidative enzymes COX-2. When tested in vivo using the CFA-induced inflammatory pain model, 3a behaved as a more potent analgesic when compared to endogenous AEA or its hydrolytically stable analogue AM356. This novel analogue will serve as a very useful endocannabinoid probe.

Background: Discovery of oncogenic mutations as targets for cancer therapy revolutionized treatment of GIST and other cancers. However, nearly all patients ultimately progress, which emphasizes the need for development of new tools to assess cancer prognosis and factors associated with benefit of cancer therapies. Altered metabolism is a hallmark of cancer, enabling tumors to proliferate, survive and metastasize. By measuring the complete set of metabolites in an individual (metabolome) it is possible to identify biomarkers that correlate with disease status, prognosis, and therapeutic response. Methods: We performed untargeted NMR and MS-based machine learning metabolomic analysis (Olaris, Waltham, MA) of serial plasma samples collected at baseline and during experimental systemic therapies in 39 patients with advanced/metastatic GIST. Results were compared to clinical outcomes. Results: In serial plasma samples from 39 patients with advanced/metastatic GIST using untargeted NMR and MS-based machine learning (ML) metabolomic analysis, we identified metabolic signatures to build Biomarker-of-Response (BoR) ML models that could accurately differentiate patients with response, intrinsic and adaptive resistance to experimental systemic therapies. The BoR ML model also correlated with tumor growth or tumor reduction in patients with response, intrinsic and adaptive resistance. Finally, we identified metabolic pathways associated with response and resistance. Conclusions: Comprehensive metabolomic profiling of serially collected plasma is feasible and detects metabolic signatures associated with therapeutic response in advanced GIST. Citation Format: Chandrashekhar Honrao, Srihari Raghavendra Rao, Nathalie Teissier, S. Greg Call, Elizabeth M. ODay, Filip Janku. Plasma based metabolic profiling in metastatic gastrointestinal stromal tumors (GIST) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB031.

In pursuit of safer controlled-deactivation cannabinoids with high potency and short duration of action, we report the design, synthesis, and pharmacological evaluation of novel C9- and C11-hydroxy-substituted hexahydrocannabinol (HHC) and tetrahydrocannabinol (THC) analogues in which a seven atom long side chain, with or without 1'-substituents, carries a metabolically labile 2',3'-ester group. Importantly, in vivo studies validated our controlled deactivation approach in rodents and non-human primates. The lead molecule identified here, namely, butyl-2-[(6aR,9R,10aR)-1-hydroxy-9-(hydroxymethyl)-6,6-dimethyl-6a,7,8,9,10,10a-hexahydro-6H-benzo[c]chromen-3-yl]-2-methylpropanoate (AM7499), was found to exhibit remarkably high in vitro and in vivo potency with shorter duration of action than the currently existing classical cannabinoid agonists.

Hemoglobin, the protein responsible for the red color of blood plays a very important part in 'life'- it transports oxygen, without which humans cannot survive. The idea of using purified Hemoglobin as a possible universal substitute for red blood cells has been around for almost a century. Hemoglobin formulations have important therapeutic applications, especially in case of trauma and war when requirements for blood may be very large. Manufacture of hemoglobin for use as a biopharmaceutical poses practical challenges, owing to dependence on human expired blood and fragility of the protein molecule. Biotechnology can play a critical role in breaking these barriers, by not only ensuring recombinant production of hemoglobin, but also enhancing stability of the molecule. The present article, based on a review of patents and available literature gives an insight into the IPR and technological issues involved in the commercial production of this 'life-saving' protein. There are more than 250 patents worldwide related to hemoglobin formulation, cross-linking and determination.