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The macrocyclic tetrapeptide CJ-15,208 (cyclo[Phe-D-Pro-Phe-Trp]) and its D-Trp isomer exhibit kappa opioid receptor (KOR) antagonism which prevents stress-induced reinstatement of extinguished cocaine-conditioned place preference. Here, we evaluated the effects of substitution of Trp and D-Trp on the peptides' opioid activity, antinociceptive tolerance, and the ability to prevent relapse to extinguished drug-CPP. Six analogs were synthesized using a combination of solid-phase peptide synthesis and cyclization in solution. The analogs were evaluated in vitro for opioid receptor affinity in radioligand competition binding assays, efficacy in the [35S]GTPγS assay, metabolic stability in mouse liver microsomes, and for opioid activity and selectivity in vivo in the mouse 55 °C warm-water tail-withdrawal assay. Potential liabilities of locomotor impairment, respiratory depression, acute tolerance, and conditioned place preference (CPP) were also assessed in vivo, and the ameliorating effect of analogs on the reinstatement of extinguished cocaine-place preference was assessed. Substitutions of other D-amino acids for D-Trp did not affect (or in one case increased) KOR affinity, while two of the three substitutions of an L-amino acid for Trp decreased KOR affinity. In contrast, all but one substitution increased mu opioid receptor (MOR) affinity in vitro. The metabolic stabilities of the analogs were similar to those of their respective parent peptides, with analogs containing a D-amino acid being much more rapidly metabolized than those containing an L-amino acid in this position. In vivo, CJ-15,208 analogs demonstrated antinociception, although potencies varied over an 80-fold range and the mediating opioid receptors differed by substitution. KOR antagonism was lost for all but the D-benzothienylalanine analog, and the 2'-naphthylalanine analog instead demonstrated significant delta opioid receptor (DOR) antagonism. Introduction of DOR antagonism coincided with reduced acute opioid antinociceptive tolerance and prevented stress-induced reinstatement of extinguished cocaine-CPP.
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Between 2012 and 2014, 715 green coffee samples were gathered by Almacafé S.A. (Bogotá, Colombia) from 27 countries. These were analysed at the nuclear magnetic resonance (NMR) laboratory at Universidad del Valle (Cali, Colombia). Over 1000 methanolic coffee extracts were prepared and 4563 spectra were acquired in a fully automatic manner using a 400 MHz NMR spectrometer (Bruker Biospin, Germany). The dataset spans the variance that could be expected for an industrial application of origin monitoring, including samples from different harvest times, collected over several years, and processed by at least two distinct operators. The resulting 1D and 2D spectra can be used to develop and evaluate feature extraction methods, multivariate algorithms, and automation monitoring techniques. They can also be used as datasets for teaching, or as a reference for new studies of similar samples and approaches.
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Despite the success of combined antiretroviral therapy (cART) in reducing viral load, a substantial portion of Human Immunodeficiency Virus (HIV)+ patients report chronic pain. The exact mechanism underlying this co-morbidity even with undetectable viral load remains unknown, but the transactivator of transcription (HIV-Tat) protein is of particular interest. Functional HIV-Tat protein is observed even in cerebrospinal fluid of patients who have an undetectable viral load. It is hypothesized that Tat protein exposure is sufficient to induce neuropathic pain-like manifestations via both activation of microglia and generation of oxidative stress. iTat mice conditionally expressed Tat(1-86) protein in the central nervous system upon daily administration of doxycycline (100 mg/kg/d, i.p., up to 14 days). The effect of HIV-Tat protein exposure on the well-being of the animal was assessed using sucrose-evoked grooming and acute nesting behavior for pain-depressed behaviors, and the development of hyperalgesia assessed with warm-water tail-withdrawal and von Frey assays for thermal hyperalgesia and mechanical allodynia, respectively. Tissue harvested at select time points was used to assess ex vivo alterations in oxidative stress, astrocytosis and microgliosis, and blood-brain barrier integrity with assays utilizing fluorescence-based indicators. Tat protein induced mild thermal hyperalgesia but robust mechanical allodynia starting after 4 days of exposure, reaching a nadir after 7 days. Changes in nociceptive processing were associated with reduced sucrose-evoked grooming behavior without altering acute nesting behavior, and in spinal cord dysregulated free radical generation as measured by DCF fluorescence intensity, altered immunohistochemical expression of the gliotic markers, Iba-1 and GFAP, and increased permeability of the blood-brain barrier to the small molecule fluorescent tracer, sodium fluorescein, in a time-dependent manner. Pretreatment with the anti-inflammatory, indomethacin (1 mg/kg/d, i.p.), the antioxidant, methylsulfonylmethane (100 mg/kg/d i.p.), or the immunomodulatory agent, dimethylfumarate (100 mg/kg/d p.o.) thirty minutes prior to daily injections of doxycycline (100 mg/kg/d i.p.) over 7 days significantly attenuated the development of Tat-induced mechanical allodynia. Collectively, the data suggests that even acute exposure to HIV-1 Tat protein at pathologically relevant levels is sufficient to produce select neurophysiological and behavioral manifestations of chronic pain consistent with that reported by HIV-positive patients.
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Dor Crônica , Infecções por HIV , Humanos , Camundongos , Animais , Antioxidantes/farmacologia , HIV , Transativadores , Dor Crônica/tratamento farmacológico , Anti-Inflamatórios , Produtos do Gene tat , Infecções por HIV/tratamento farmacológico , SacaroseRESUMO
BACKGROUND: Burnout syndrome, from the sporting point of view, is the integration of both physical and emotional signs, caused by the high demands in competition. According to several studies, the prevalence of burnout syndrome is influenced by several factors that would lead to athlete's body image dissatisfaction. METHODS: The study design is cross-sectional analysis. The study sample was 352 athletes selected from the Universidad Peruana de Ciencias Aplicadas (UPC). The main variables of this study are the burnout syndrome; which was measured by Athlete Burnout Questionnaire (ABQ) and body image dissatisfaction, through thirteen Scale drawings contour figure Gardner. To find the association between body image dissatisfaction and burnout syndrome Poisson regression was used. RESULTS: Athletes with burnout syndrome have 1.08 times more likely having body image dissatisfaction with a value P=0.011 (95% CI: 1.02-1.15). It was also found that a sport collectively practiced is a protective factor for Burnout Syndrome with P=0.015 (95% CI: 0.4-0.9). CONCLUSIONS: Relation between burnout syndrome and body image dissatisfaction in athletes was found. In addition, a relationship between practicing an individual sport and burnout syndrome was also found. More studies are necessary to confirm these relationships.
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Atletas/psicologia , Insatisfação Corporal , Esgotamento Profissional/psicologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Esportes/psicologia , Inquéritos e Questionários , Universidades , Adulto JovemRESUMO
Sigma-1 receptors (S1R) and sigma-2 receptors (S2R) may modulate nociception without the liabilities of opioids, offering a promising therapeutic target to treat pain. The purpose of this study was to investigate the in vivo analgesic and anti-allodynic activity of two novel sigma receptor antagonists, the S1R-selective CM-304 and its analog the non-selective S1R/S2R antagonist AZ-66. Inhibition of thermal, induced chemical or inflammatory pain, as well as the allodynia resulting from chronic nerve constriction injury (CCI) and cisplatin exposure as models of neuropathic pain were assessed in male mice. Both sigma receptor antagonists dose-dependently (10-45 mg/kg, i.p.) reduced allodynia in the CCI and cisplatin neuropathic pain models, equivalent at the higher dose to the effect of the control analgesic gabapentin (50 mg/kg, i.p.), although AZ-66 demonstrated a much longer duration of action. Both CM-304 and AZ-66 produced antinociception in the writhing test [0.48 (0.09-1.82) and 2.31 (1.02-4.81) mg/kg, i.p., respectively] equivalent to morphine [1.75 (0.31-7.55) mg/kg, i.p.]. Likewise, pretreatment (i.p.) with either sigma-receptor antagonist dose-dependently produced antinociception in the formalin paw assay of inflammatory pain. However, CM-304 [17.5 (12.7-25.2) mg/kg, i.p.) and AZ-66 [11.6 (8.29-15.6) mg/kg, i.p.) were less efficacious than morphine [3.87 (2.85-5.18) mg/kg, i.p.] in the 55°C warm-water tail-withdrawal assay. While AZ-66 exhibited modest sedative effects in a rotarod assay and conditioned place aversion, CM-304 did not produce significant effects in the place conditioning assay. Overall, these results demonstrate the S1R selective antagonist CM-304 produces antinociception and anti-allodynia with fewer liabilities than established therapeutics, supporting the use of S1R antagonists as potential treatments for chronic pain.
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BACKGROUND: The prevalence of major depression in those with HIV/AIDS is substantially higher than in the general population. Mechanisms underlying this comorbidity are poorly understood. HIV-transactivator of transcription (Tat) protein, produced and excreted by HIV, could be involved. We determined whether conditional Tat protein expression in mice is sufficient to induce depression-like behaviors and oxidative stress. Further, as oxidative stress is associated with depression, we determined whether decreasing or increasing oxidative stress by administering methylsulfonylmethane (MSM) or diethylmaleate (DEM), respectively, altered depression-like behavior. METHODS: GT-tg bigenic mice received intraperitoneal saline or doxycycline (Dox, 25-100 mg/kg/day) to induce Tat expression. G-tg mice, which do not express Tat protein, also received Dox. Depression-like behavior was assessed with the tail suspension test (TST) and the two-bottle saccharin/water consumption task. Reactive oxygen/nitrogen species (ROS/RNS) were assessed ex vivo. Medial frontal cortex (MFC) oxidative stress and temperature were measured in vivo with 9.4-Tesla proton magnetic resonance spectroscopy (MRS). RESULTS: Tat expression increased TST immobility time in an exposure-dependent manner and reduced saccharin consumption. MSM decreased immobility time while DEM increased it in saline-treated GT-tg mice. Tat and MSM behavioral effects persisted for 28 days. Tat and DEM increased while MSM decreased ROS/RNS levels. Tat expression increased MFC glutathione levels and temperature. CONCLUSIONS: Tat expression induced rapid and enduring depression-like behaviors and oxidative stress. Increasing/decreasing oxidative stress increased/decreased, respectively, depression-like behavior. Thus, Tat produced by HIV may contribute to the high depression prevalence among those with HIV. Further, mitigation of oxidative stress could reduce depression severity.
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Natural products found in Mitragyna speciosa, commonly known as kratom, represent diverse scaffolds (indole, indolenine, and spiro pseudoindoxyl) with opioid activity, providing opportunities to better understand opioid pharmacology. Herein, we report the pharmacology and SAR studies both in vitro and in vivo of mitragynine pseudoindoxyl (3), an oxidative rearrangement product of the corynanthe alkaloid mitragynine. 3 and its corresponding corynantheidine analogs show promise as potent analgesics with a mechanism of action that includes mu opioid receptor agonism/delta opioid receptor antagonism. In vitro, 3 and its analogs were potent agonists in [(35)S]GTPγS assays at the mu opioid receptor but failed to recruit ß-arrestin-2, which is associated with opioid side effects. Additionally, 3 developed analgesic tolerance more slowly than morphine, showed limited physical dependence, respiratory depression, constipation, and displayed no reward or aversion in CPP/CPA assays, suggesting that analogs might represent a promising new generation of novel pain relievers.
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Analgésicos Opioides/farmacologia , Receptores Opioides delta/antagonistas & inibidores , Receptores Opioides mu/agonistas , Alcaloides de Triptamina e Secologanina/farmacologia , beta-Arrestina 2/metabolismo , Analgésicos Opioides/química , Animais , Linhagem Celular , Humanos , Masculino , Camundongos , Mitragyna/química , Simulação de Acoplamento Molecular , Receptores Opioides delta/metabolismo , Receptores Opioides mu/metabolismo , Alcaloides de Triptamina e Secologanina/químicaRESUMO
Maladaptive behavioral responses characteristic of post-traumatic stress disorders are notably resistant to treatment. We hypothesized that the pharmacological disruption of memories activated during reconsolidation might reverse established stress-induced increases in depression-like behaviors and cocaine reward. C57BL/6J mice were subjected to repeated social defeat stress (SDS), and examined for time spent immobile in a subsequent forced swim test (FST). An additional set of SDS-exposed mice were place-conditioned with cocaine, and tested for cocaine-conditioned place preference (CPP). All stress-exposed mice were then subjected to a single additional trial of SDS while under the influence of propranolol or cycloheximide to disrupt memory reconsolidation, then given one additional FST or CPP test the next day. Mice subjected to repeated SDS subsequently demonstrated increases in time spent immobile in the FST or in the cocaine-paired chamber. Vehicle-treatment followed by additional SDS exposure did not alter these behaviors, but propranolol or cycloheximide treatment reversed each of the potentiated responses in a dose-dependent manner. Overall, these results demonstrate that while repeated exposure to a social defeat stressor subsequently increased depression-like behavior and cocaine-CPP, disruption of traumatic memories made labile by re-exposure to SDS during reconsolidation may have therapeutic value in the treatment of established post-traumatic stress disorder-related behaviors.