Analysis of Relationships between DAT1 Polymorphism Variants, Personality Dimensions, and Anxiety in New Psychoactive Substance (Designer Drug) (NPS) Users.

The use of 'new psychoactive substances' appears to be increasingly common. The aim of this study was to examine biological and personality determinants in individuals who choose to use these substances, which may help in the prevention and treatment of psychoactive substance use disorders. The study group consisted of 374 male volunteers; all were users of 'new psychoactive substances' (NPS). The NPS users were recruited after they had abstained-for at least 3 months-from any substance of abuse in addiction treatment facilities. The NPS patients and the control subjects were examined by a psychiatrist using the Mini-International Neuropsychiatric Interview (M.I.N.I.), the NEO Five-Factor Personality Inventory (NEO-FFI), and the State-Trait Anxiety Inventory (STAI) scales. The real-time PCR method was used for genotyping. When we compared the controls with the study group, statistically significant interactions were found between DAT1 polymorphism, neuroticism, and NPS use. NPS use and DAT1 polymorphism were associated with a higher level of neuroticism on the NEO-FFI scale. The study group of NPS users showed a higher severity of anxiety symptoms, both in terms of trait and state, compared to the control group. The results may support the idea that neuroticism and anxiety correlate strongly with coping motives for using NPS.

Medicinal Use of Testosterone and Related Steroids Revisited.

Testosterone derivatives and related compounds (such as anabolic-androgenic steroids-AAS) are frequently misused by athletes (both professional and amateur) wishing to promote muscle development and strength or to cover AAS misuse. Even though these agents are vastly regarded as abusive material, they have important pharmacological activities that cannot be easily replaced by other drugs and have therapeutic potential in a range of conditions (e.g., wasting syndromes, severe burns, muscle and bone injuries, anemia, hereditary angioedema). Testosterone and related steroids have been in some countries treated as controlled substances, which may affect the availability of these agents for patients who need them for therapeutic reasons in a given country. Although these agents are currently regarded as rather older generation drugs and their use may lead to serious side-effects, they still have medicinal value as androgenic, anabolic, and even anti-androgenic agents. This review summarizes and revisits the medicinal use of compounds based on the structure and biological activity of testosterone, with examples of specific compounds. Additionally, some of the newer androgenic-anabolic compounds are discussed such as selective androgen receptor modulators, the efficacy/adverse-effect profiles of which have not been sufficiently established and which may pose a greater risk than conventional androgenic-anabolic agents.

Designer drugs: a medicinal chemistry perspective (II).

During 2012-2018, the clandestine manufacture of new psychoactive substances (NPS) designed to circumvent substance control regulations increased exponentially worldwide, with concomitant increase in fatalities. This review focuses on three compound classes identified as synthetic opioids, synthetic amphetamines, and synthetic cannabinoids and highlights the medicinal chemistry precedents utilized by clandestine laboratories to develop new NPS with increased brain penetration, longer duration of action, and greater potency. Chemical approaches to illicit drug abuse treatment options, particularly for opioid use disorder, are also discussed.

Designer Receptors Exclusively Activated by Designer Drugs Approach to Treatment of Sleep-disordered Breathing.

Rationale: Obstructive sleep apnea is recurrent upper airway obstruction caused by a loss of upper airway muscle tone during sleep. The main goal of our study was to determine if designer receptors exclusively activated by designer drugs (DREADD) could be used to activate the genioglossus muscle as a potential novel treatment strategy for sleep apnea. We have previously shown that the prototypical DREADD ligand clozapine-N-oxide increased pharyngeal diameter in mice expressing DREADD in the hypoglossal nucleus. However, the need for direct brainstem viral injections and clozapine-N-oxide toxicity diminished translational potential of this approach, and breathing during sleep was not examined.Objectives: Here, we took advantage of our model of sleep-disordered breathing in diet-induced obese mice, retrograde properties of the adeno-associated virus serotype 9 (AAV9) viral vector, and the novel DREADD ligand J60.Methods: We administered AAV9-hSyn-hM3(Gq)-mCherry or control AAV9 into the genioglossus muscle of diet-induced obese mice and examined the effect of J60 on genioglossus activity, pharyngeal patency, and breathing during sleep.Measurements and Main Results: Compared with control, J60 increased genioglossus tonic activity by greater than sixfold and tongue uptake of 2-deoxy-2-[18F]fluoro-d-glucose by 1.5-fold. J60 increased pharyngeal patency and relieved upper airway obstruction during non-REM sleep.Conclusions: We conclude that following intralingual administration of AAV9-DREADD, J60 can activate the genioglossus muscle and improve pharyngeal patency and breathing during sleep.

Designer broad-spectrum polyimidazolium antibiotics.

For a myriad of different reasons most antimicrobial peptides (AMPs) have failed to reach clinical application. Different AMPs have different shortcomings including but not limited to toxicity issues, potency, limited spectrum of activity, or reduced activity in situ. We synthesized several cationic peptide mimics, main-chain cationic polyimidazoliums (PIMs), and discovered that, although select PIMs show little acute mammalian cell toxicity, they are potent broad-spectrum antibiotics with activity against even pan-antibiotic-resistant gram-positive and gram-negative bacteria, and mycobacteria. We selected PIM1, a particularly potent PIM, for mechanistic studies. Our experiments indicate PIM1 binds bacterial cell membranes by hydrophobic and electrostatic interactions, enters cells, and ultimately kills bacteria. Unlike cationic AMPs, such as colistin (CST), PIM1 does not permeabilize cell membranes. We show that a membrane electric potential is required for PIM1 activity. In laboratory evolution experiments with the gram-positive Staphylococcus aureus we obtained PIM1-resistant isolates most of which had menaquinone mutations, and we found that a site-directed menaquinone mutation also conferred PIM1 resistance. In similar experiments with the gram-negative pathogen Pseudomonas aeruginosa, PIM1-resistant mutants did not emerge. Although PIM1 was efficacious as a topical agent, intraperitoneal administration of PIM1 in mice showed some toxicity. We synthesized a PIM1 derivative, PIM1D, which is less hydrophobic than PIM1. PIM1D did not show evidence of toxicity but retained antibacterial activity and showed efficacy in murine sepsis infections. Our evidence indicates the PIMs have potential as candidates for development of new drugs for treatment of pan-resistant bacterial infections.

Rational Cancer Treatment Combinations: An Urgent Clinical Need.

We are witnessing several revolutionary technological advances in cancer. These innovations have not only contributed to a growing understanding of the tumor and its microenvironment but also uncovered an increasing array of new therapeutic targets. For most advanced cancers, therapy resistance limits the benefit of single-agent therapies. Therefore, some 5,000 clinical trials are ongoing globally to probe the clinical benefit of new combination treatments. However, the possibilities to combine individual treatments dramatically outnumber the patients available to enroll in clinical trials. This comes at a potential cost of missed opportunities, clinical failure, avoidable toxicity, insufficient patient accrual, and financial loss. A solution may be to design combination therapies more rationally, which are informed by fundamental biological and mechanistic insight. We will discuss some successes and failures of current treatment combinations, as well as interesting emerging preclinical concepts that warrant clinical exploration.

CRISPR, Prime Editing, Optogenetics, and DREADDs: New Therapeutic Approaches Provided by Emerging Technologies in the Treatment of Spinal Cord Injury.

Spinal cord injury (SCI) causes temporary disabilities or permanent effects including neuropathic pain and spastiscity. The damage often results from mechanical trauma, which in turn triggers the neuroinflammatory process. Neuroinflammation plays essential roles in the structural, biochemical, and cellular changes that take place in the spinal cord after the injury. Indeed, SCI activates many different signaling pathways that coordinate the resulting cellular responses. While neuroinflammation serves as a physiological reaction to harmful stimuli, it is clear that long-lasting inflammatory response leads to aggravation of the neurodegenerative processes, becoming detrimental to recovery post-injury. In this context, we present some possible therapeutic targets in these activated signaling pathways and provide new perspectives for SCI treatment based on recently developed technologies, including clustered regularly interspaced short palindromic repeats (CRISPR)-based methods (including prime editing), optogenetics, and designer receptor exclusively activated by designer drugs (DREADDs). We critically analyze the recent advances in the deployment of these methods focusing on the control of the initial neuroinflammatory response. We then propose alternatives and provide new avenues for SCI treatment based on these emerging technologies.

Chemogenetic activation of the lateral hypothalamus reverses early life stress-induced deficits in motivational drive.

Altered motivated behaviour is a cardinal feature of several neuropsychiatric conditions including mood disorders. One well-characterized antecedent to the development of mood disorders is exposure to early life stress (ELS). A key brain substrate controlling motivated behaviour is the lateral hypothalamus (LH). Here, we examined the effect of ELS on LH activation and the motivation to self-administer sucrose. We tested whether chemogenetic activation of LH circuits could modify sucrose responding in ELS rats and examined the impact on LH cell populations. Male rat pups were maternally separated for 0 or 3 h on postnatal days 2-14. During adolescence, rats received bilateral injections of hM3D(Gq), the excitatory designer receptor exclusively activated by designer drugs, into LH. In adulthood, rats were trained to self-administer sucrose and tested under a progressive ratio schedule to determine their motivation for reward following injection with either vehicle or 5 mg/kg clozapine-N-oxide. Brains were processed for Fos-protein immunohistochemistry. ELS significantly suppressed lever responding for sucrose, indicating a long-lasting impact of ELS on motivation circuits. hM3D(Gq) activation of LH increased responding, normalizing deficits in ELS rats, and increased Fos-positive orexin and MCH cell numbers within LH. Our findings indicate that despite being susceptible to environmental stressors, LH circuits retain the capacity to overcome ELS-induced deficits in motivated behaviour.

Designer Drugs 2.0.

This "Designer Drugs 2.0" issue of Clinical Pharmacology & Therapeutics focuses on novel psychoactive substances, primarily cannabinoids and cathinones, and the repurposing of established psychoactive compounds (e.g., modafinil, psilocybin, lysergic acid diethylamide, and 3,4-methylenedioxymethamphetamine) that simultaneously offer new pharmacotherapies and pose serious health problems. Novel psychoactive substances were initially used as potent tools to investigate endogenous neurotransmitter systems; for example, synthetic cannabinoids have much higher potency than Δ9-tetrahydrocannabinol at the cannabinoid receptors. However, they are now being used illicitly as well as being tested for their efficacy in numerous clinical indications. Likewise, previously established psychoactive drugs are being repurposed as treatments for a wide variety of indications where currently approved medications are ineffective. This set of papers examines the arising problems associated with designer drugs (e.g., adverse events, psychosis, rapid new synthesis, abuse liability testing, internet sales, scheduling) as well as the potential therapeutic promises in areas as diverse as cognition enhancement, exercise-mimetics, epilepsy, multiple sclerosis, and posttraumatic stress disorder.

The Mind Bending Quest for Cognitive Enhancers.

Adequate cognitive functioning is essential for daily activities. When there is an insult to the brain, cognitive abilities can suffer, which, in turn, produce substantial medical and functional impairment. Advances in neurobiology, circuit neuroscience, and clinical assessment technology are converging in a manner that holds promise for the development of new pharmacological agents for cognitive enhancement in neuropsychiatric disease.

Designer Thiopurine-analogues for Optimised Immunosuppression in Inflammatory Bowel Diseases.

BACKGROUND AND AIMS: The clinical use of azathioprine and 6-mercaptopurine is limited by their delayed onset of action and potential side effects such as myelosuppression and hepatotoxicity. As these drugs specifically target the Vav1/Rac1 signalling pathway in T lamina propria lymphocytes via their metabolite 6-thio-GTP, we studied expression and optimised suppression of this pathway in inflammatory bowel diseases [IBD]. METHODS: Rac1 and Vav1 expressions were analysed in mucosal immune cells in IBD patients. Targeted molecular modelling of the 6-thio-GTP molecule was performed to optimise Rac1 blockade; 44 modified designer thiopurine-analogues were tested for apoptosis induction, potential toxicity, and immunosuppression. Activation of the Vav1/Rac1 pathway in lymphocytes was studied in IBD patients and in lamina propria immune cells in the presence or absence of thiopurine-analogues. RESULTS: Several thiopurine-analogues induced significantly higher T cell apoptosis than 6-mercaptopurine. We identified a compound, denoted B-0N, based on its capacity to mediate earlier and stronger induction of T cell apoptosis than 6-mercaptopurine. B-0N-treatment resulted in accelerated inhibition of Rac1 activity in primary peripheral blood T cells as well as in intestinal lamina propria immune cells. Compared with 6-thio-GTP and 6-mercaptopurine, B-0N-treatment was associated with decreased myelo- and hepatotoxicity. CONCLUSIONS: The Vav1/Rac1 pathway is activated in mucosal immune cells in IBD. The designer thiopurine-analogue B-0N induces immunosuppression more potently than 6-mercaptopurine.

DREADDS: Use and application in behavioral neuroscience.

Technological advances over the last decade are changing the face of behavioral neuroscience research. Here we review recent work on the use of one such transformative tool in behavioral neuroscience research, chemogenetics (or Designer Receptors Exclusively Activated by Designer Drugs, DREADDS). As transformative technologies such as DREADDs are introduced, applied, and refined, their utility in addressing complex questions about behavior and cognition becomes clear and exciting. In the behavioral neuroscience field, remarkable new findings now regularly appear as a result of the ability to monitor and intervene in neural processes with high anatomical precision as animals behave in complex task environments. As these new tools are applied to behavioral questions, individualized procedures for their use find their way into diverse labs. Thus, "tips of the trade" become important for wide dissemination not only for laboratories that are using the tools but also for those who are interested in incorporating them into their own work. Our aim is to provide an up-to-date perspective on how the DREADD technique is being used for research on learning and memory, decision making, and goal-directed behavior, as well as to provide suggestions and considerations for current and future users based on our collective experience. (PsycINFO Database Record

Attenuation of ß-Amyloid Deposition and Neurotoxicity by Chemogenetic Modulation of Neural Activity.

Aberrant neural hyperactivity has been observed in early stages of Alzheimer's disease (AD) and may be a driving force in the progression of amyloid pathology. Evidence for this includes the findings that neural activity may modulate ß-amyloid (Aß) peptide secretion and experimental stimulation of neural activity can increase amyloid deposition. However, whether long-term attenuation of neural activity prevents the buildup of amyloid plaques and associated neural pathologies remains unknown. Using viral-mediated delivery of designer receptors exclusively activated by designer drugs (DREADDs), we show in two AD-like mouse models that chronic intermittent increases or reductions of activity have opposite effects on Aß deposition. Neural activity reduction markedly decreases Aß aggregation in regions containing axons or dendrites of DREADD-expressing neurons, suggesting the involvement of synaptic and nonsynaptic Aß release mechanisms. Importantly, activity attenuation is associated with a reduction in axonal dystrophy and synaptic loss around amyloid plaques. Thus, modulation of neural activity could constitute a potential therapeutic strategy for ameliorating amyloid-induced pathology in AD. SIGNIFICANCE STATEMENT: A novel chemogenetic approach to upregulate and downregulate neuronal activity in Alzheimer's disease (AD) mice was implemented. This led to the first demonstration that chronic intermittent attenuation of neuronal activity in vivo significantly reduces amyloid deposition. The study also demonstrates that modulation of ß-amyloid (Aß) release can occur at both axonal and dendritic fields, suggesting the involvement of synaptic and nonsynaptic Aß release mechanisms. Activity reductions also led to attenuation of the synaptic pathology associated with amyloid plaques. Therefore, chronic attenuation of neuronal activity could constitute a novel therapeutic approach for AD.

Inhibiting the growth of pancreatic adenocarcinoma in vitro and in vivo through targeted treatment with designer gold nanotherapeutics.

BACKGROUND: Pancreatic cancer is one of the deadliest of all human malignancies with limited options for therapy. Here, we report the development of an optimized targeted drug delivery system to inhibit advanced stage pancreatic tumor growth in an orthotopic mouse model. METHODPRINCIPAL FINDINGS: Targeting specificity in vitro was confirmed by preincubation of the pancreatic cancer cells with C225 as well as Nitrobenzylthioinosine (NBMPR - nucleoside transporter (NT) inhibitor). Upon nanoconjugation functional activity of gemcitabine was retained as tested using a thymidine incorporation assay. Significant stability of the nanoconjugates was maintained, with only 12% release of gemcitabine over a 24-hour period in mouse plasma. Finally, an in vivo study demonstrated the inhibition of tumor growth through targeted delivery of a low dose of gemcitabine in an orthotopic model of pancreatic cancer, mimicking an advanced stage of the disease. CONCLUSION: We demonstrated in this study that the gold nanoparticle-based therapeutic containing gemcitabine inhibited tumor growth in an advanced stage of the disease in an orthotopic model of pancreatic cancer. Future work would focus on understanding the pharmacokinetics and combining active targeting with passive targeting to further improve the therapeutic efficacy and increase survival.

Next generation of antimicrobial peptides as molecular targeted medicines.

Antibiotics have significantly improved our living environments. However, overuse of antibiotics has led to the emergence of multi-drug resistant microorganisms, and the subsequent constant demand for the exploration of novel antibiotics. To this end, antimicrobial peptides (AMPs) have attracted much attention as a novel class of antibiotics. AMPs have strong antimicrobial activity against a wide-range of species, including gram-positive and gram-negative bacteria, fungi, and viruses. In addition, they are also effective against pathogenic organisms that are resistant to conventional drugs. Despite their great potential, the hemolytic activity and a highly broad spectrum of activity of AMPs dictate the need for amendments to develop safe pharmaceuticals. The human body contains commensal microflora as an integral part of complex mucosal surfaces that offers protection against pathogenic organisms. Administration of antibiotics with broad spectra of activity disrupts the indigenous microflora and increases the risks of diarrhea and other fatal infections. Therefore, it is difficult, but vital, to develop treatments capable of rapidly eliminating pathogenic organisms while maintaining the commensal microbiota. As such, novel pharmaceuticals, safe designer AMPs have been heavily researched. In this article, we review recent attempts to spatially and temporally regulate AMPs to enhance the quality-of-life of patients.

The designer aminoglycoside NB84 significantly reduces glycosaminoglycan accumulation associated with MPS I-H in the Idua-W392X mouse.

Suppression therapy utilizes compounds that suppress translation termination at in-frame premature termination codons (PTCs) to restore full-length, functional protein. This approach may provide a treatment for diseases caused by nonsense mutations such as mucopolysaccharidosis type I-Hurler (MPS I-H). MPS I-H is a lysosomal storage disease caused by severe α-L-iduronidase deficiency and subsequent lysosomal glycosaminoglycan (GAG) accumulation. MPS I-H represents a good target for suppression therapy because the majority of MPS I-H patients carry nonsense mutations, and restoration of even a small amount of functional α-L-iduronidase may attenuate the MPS I-H phenotype. In this study, we investigated the efficiency of suppression therapy agents to suppress the Idua-W392X nonsense mutation in an MPS I-H mouse model. The drugs tested included the conventional aminoglycosides gentamicin, G418, amikacin, and paromomycin. In addition, the designer aminoglycosides NB54 and NB84, two compounds previously designed to mediate efficient PTC suppression with reduced toxicity, were also examined. Overall, NB84 suppressed the Idua-W392X nonsense mutation much more efficiently than any of the other compounds tested. NB84 treatment restored enough functional α-L-iduronidase activity to partially reverse abnormal GAG accumulation and lysosomal abundance in mouse embryonic fibroblasts derived from the Idua-W392X mouse. Finally, in vivo administration of NB84 to Idua-W392X mice significantly reduced urine GAG excretion and tissue GAG storage. Together, these results suggest that NB84-mediated suppression therapy has the potential to attenuate the MPS I-H disease phenotype.

Designer natriuretic peptides: a vision for the future of heart failure therapeutics.

Despite recent pharmacological advances in heart failure therapy, mortality from acute decompensated heart failure remains high. Conventional therapies are often insufficient to address the complex interplay between structural, functional, neurohumoral, and renal mechanisms involved in the heart failure syndrome. The natriuretic peptide system, however, offers a unique pleiotropic strategy which could bridge this gap in heart failure therapy. Exogenous administration of native A-type and B-type natriuretic peptides has been met with both success and limitations, and despite the limitations, remains a worthwhile endeavor. Alternatively, synthetic modification to create "designer" chimeric peptides holds the possibility to extend both the application and therapeutic benefits possible with a natriuretic peptide based approach. Herein we describe the development of natriuretic peptide based heart failure therapies, including the design, rationale, and preliminary studies of the novel chimeric peptides CD-NP and CU-NP.