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1.
Cancer Manag Res ; 16: 283-297, 2024.
Article in English | MEDLINE | ID: mdl-38617187

ABSTRACT

Purpose: Although risk factors related to chemotherapy-induced nausea and vomiting (CINV) have been identified in previous studies, only a few studies have evaluated the risk factors associated with contemporary antiemetic prophylaxis, including olanzapine/aprepitant- or NEPA-containing regimens. This study aimed to identify the risk factors associated with CINV development in Chinese breast cancer patients receiving doxorubicin and cyclophosphamide chemotherapy. Methods: Data from 304 patients enrolled in 3 previously reported prospective antiemetic studies were included. Multivariate logistic regression models were used to predict risk factors associated with CINV occurrence. Additionally, the likelihood of treatment failure in relation to the number of risk factors in individual patients was evaluated. Results: Multivariate analysis of the entire study group revealed that obesity status (defined as body mass index/= 25.0 kg/m2) and the use of olanzapine/aprepitant- or NEPA-containing anti-emetic regimens were associated with a high likelihood, while a history of motion sickness was associated with a lower likelihood, complete response (CR), and "no nausea" in the overall phase. A history of vomiting during pregnancy was also associated with a lower likelihood of an overall CR. Patients with an increasing number of risk factors had a higher likelihood of treatment failure and shorter time to first vomiting. Those who did not achieve CR and "no nausea" in the first cycle were less likely to achieve these parameters in the subsequent cycle of chemotherapy. Conclusion: The present study confirmed previously reported risk factors for CINV in Chinese breast cancer patients receiving doxorubicin and cyclophosphamide. Further optimization of CINV control is required for patients with identifiable risk factors; olanzapine/aprepitant- or NEPA- containing prophylaxis are the preferred contemporary anti-emetics regimens for Chinese breast cancer patients undergoing doxorubicin and cyclophosphamide chemotherapy.

2.
Article in English | MEDLINE | ID: mdl-34477962

ABSTRACT

How do animals use visual systems to extract specific features of a visual scene and respond appropriately? The medicinal leech, Hirudo verbana, is a predatory, quasi-amphibious annelid with a rich sensorium that is an excellent system in which to study how sensory cues are encoded, and how key features of visual images are mapped into the CNS. The leech visual system is broadly distributed over its entire body, consisting of five pairs of cephalic eyecups and seven segmentally iterated pairs of dermal sensilla in each mid-body segment. Leeches have been shown to respond behaviorally to both green and near ultraviolet light (UV, 365-375 nm). Here, we used electrophysiological techniques to show that spectral responses by dermal sensilla are mapped across the dorsal-ventral axis, such that the ventral sensilla respond strongly to UV light, while dorsal sensilla respond strongly to visible light, broadly tuned around green. These results establish how key features of visual information are initially encoded by spatial mapping of photo-response profiles of primary photoreceptors and provide insight into how these streams of information are presented to the CNS to inform behavioral responses.


Subject(s)
Hirudo medicinalis/metabolism , Photic Stimulation/methods , Photoreceptor Cells, Invertebrate/metabolism , Sensilla/metabolism , Animals , Hirudo medicinalis/chemistry , Mechanoreceptors/chemistry , Mechanoreceptors/metabolism , Photoreceptor Cells, Invertebrate/chemistry , Sensilla/chemistry
3.
Oncologist ; 26(12): e2288-e2296, 2021 12.
Article in English | MEDLINE | ID: mdl-34516038

ABSTRACT

BACKGROUND: There is limited work on the impact of chemotherapy-induced nausea and vomiting (CINV) on quality of life (QoL) in adriamycin-cyclophosphamide (AC)-treated patients with breast cancer. The objectives of the study were the following: (a) to confirm if symptoms of CINV led to lower QoL during AC; (b) to evaluate the pattern of changes in patients' QoL during multiple cycles of AC; and (c) to assess if the QoL in an earlier cycle affected the QoL in subsequent cycles of AC. MATERIALS AND METHODS: This is a secondary pooled data analysis that included 303 Chinese patients with breast cancer who received 1,177 cycles of adjuvant AC in three prospective antiemetic studies. QoL data were based on Functional Living Index-emesis (FLIE) scored over three to four AC cycles. CINV symptoms assessed included "no significant nausea" (NSN), "significant nausea" (SN), "no vomiting" (NoV), "vomiting" (V), and complete response (CR). RESULTS: Across all AC cycles, the mean scores for the FLIE nausea domain for patients who experienced NSN versus SN were 10.92 versus 53.92, respectively (p < .0001), with lower scores indicating better QoL; the mean scores for the FLIE vomiting domain for patients who experienced NoV versus V were 1.44 versus 19.11, respectively (p < .0001), with similar results across subsequent cycles. Analysis of the effect of the QoL in cycle 1 on the QoL of subsequent cycles revealed the following: for the nausea domain, among patients who had cycle 1 FLIE scores ≥ versus < the mean, the corresponding scores in cycle 2 were 6.87 versus 36.71 (p < .0001); whereas those for cycle 3 were 7.07 versus 36.87 (p < .0001); and those for cycle 4 were 5.92 versus 21.48 (p < .0001). Similar findings were observed for the vomiting domain. Netupitant + palonosetron- or aprepitant/olanzapine-based antiemetics had significantly better QoL outcomes. CONCLUSION: CINV had a significant impact on the QoL of patients with breast cancer treated with AC over multiple cycles. IMPLICATIONS FOR PRACTICE: In this post-hoc analysis of three prospective studies on chemotherapy-induced nausea and vomiting (CINV), quality of life (QoL) using contemporary antiemetic regimens in Chinese breast cancer patients receiving doxorubicin-cyclophosphamide (AC) was evaluated. During the first and subsequent AC cycles, QoL was significantly better for patients who did not experience vomiting or significant nausea. QoL in an earlier cycle affected the QoL in subsequent AC cycles. Furthermore, recent regimens involving olanzapine/aprepitant or netupitant-palonosetron were associated with a positive impact in QoL. Antiemetic guideline-consistent practice and higher clinician awareness of the impact of CINV on QoL can further mitigate the negative effects of CINV on QoL.


Subject(s)
Anthracyclines , Quality of Life , Anthracyclines/adverse effects , Data Analysis , Humans , Nausea/chemically induced , Prospective Studies , Vomiting/chemically induced
4.
Clin Cancer Res ; 27(10): 2827-2836, 2021 05 15.
Article in English | MEDLINE | ID: mdl-33692028

ABSTRACT

PURPOSE: To study the dynamic changes in plasma Epstein-Barr virus (pEBV) DNA after radiotherapy in nasopharyngeal cancer (NPC). EXPERIMENTAL DESIGN: We conducted a randomized controlled trial of adjuvant chemotherapy versus observation in patients with NPC who had detectable pEBV DNA at 6 weeks post-radiotherapy. Randomized patients had a second pEBV DNA checked at 6 months post-randomization. The primary endpoint was progression-free survival (PFS). RESULTS: We prospectively enrolled 789 patients. Baseline post-radiotherapy pEBV DNA was undetectable in 573 (72.6%) patients, and detectable in 216 (27.4%) patients, of whom 104 (13.2%) patients were eligible for randomization to adjuvant chemotherapy (n = 52) versus observation (n = 52). The first post-radiotherapy pEBV DNA had a sensitivity of 0.48, specificity of 0.81, area under receiver-operator characteristics curve (AUC) of 0.65, false positive (FP) rate of 13.8%, and false negative (FN) rate of 14.4% for disease progression. The second post-radiotherapy pEBV DNA had improved sensitivity of 0.81, specificity of 0.75, AUC of 0.78, FP rate of 14.3%, and FN rate of 8.1%. Patients with complete clearance of post-radiotherapy pEBV DNA (51%) had survival superior to that of patients without post-radiotherapy pEBV DNA clearance (5-year PFS, 85.5% vs. 23.3%; HR, 9.6; P < 0.0001), comparable with patients with initially undetectable post-radiotherapy pEBV DNA (5-year PFS, 77.1%), irrespective of adjuvant chemotherapy or observation. CONCLUSIONS: Patients with NPC with detectable post-radiotherapy pEBV DNA who experienced subsequent pEBV DNA clearance had superior survival comparable with patients with initially undetectable post-radiotherapy pEBV DNA. Post-radiotherapy pEBV DNA clearance may serve as an early surrogate endpoint for long-term survival in NPC.


Subject(s)
DNA, Viral , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/virology , Herpesvirus 4, Human/genetics , Nasopharyngeal Neoplasms/diagnosis , Nasopharyngeal Neoplasms/etiology , Viral Load , Biomarkers, Tumor , Chemotherapy, Adjuvant/adverse effects , Chemotherapy, Adjuvant/methods , Combined Modality Therapy/adverse effects , Combined Modality Therapy/methods , DNA, Viral/blood , Disease Management , Disease Progression , Disease Susceptibility , Humans , Nasopharyngeal Neoplasms/mortality , Nasopharyngeal Neoplasms/therapy , Positron Emission Tomography Computed Tomography , Prognosis , Survival Analysis , Viral Load/methods
5.
Qual Life Res ; 30(6): 1583-1594, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33447955

ABSTRACT

PURPOSE: This study aimed to investigate changes of QoL during the first 5 years of survival among disease-free Chinese breast cancer survivors. METHODS: A prospective cohort study enrolled 1462 Chinese women with early-stage breast cancer, and longitudinally visited those patients at four time-points, namely baseline (T0), 18- (T1), 36- (T2), and 60-month (T3) after diagnosis. This study included 992 patients who were disease-free during the first 5 years of survival and who had completed QoL assessments at all four time-points. RESULTS: The score of global health status/QoL improved gradually (T1, T2, T3 > T0; P < 0.001 for overall comparisons). Social functioning score significantly improved when compared to that of T0 (T1, T2, T3 > T0; P < 0.001 for overall comparisons). In contrast, cognitive functioning score decreased (T0 > T1, T2, T3; P < 0.001 for overall comparisons). Scores of physical functioning, role functioning and emotional functioning showed a fluctuated picture, with the highest score achieved at T1. In symptoms profile, most of them scored lowest at T1 (best QoL). Multivariate analysis showed that several characteristics significantly correlated to changes in QoL from T0 to T3. For instance, patients with higher education had better recovery of physical functioning, role functioning, and social functioning. CONCLUSION: During the first 5 years of survival, patients' global health status/QoL improved over time, social functioning consistently improved, but cognitive functioning steadily deteriorated. Most of functioning domains and symptoms improved at 18-month follow-up, but such improvements were not maintained and even deteriorated at 36- and 60-month post-diagnosis. This study suggested that some interventions should be investigated during such period.


Subject(s)
Breast Neoplasms/psychology , Cancer Survivors/psychology , Health Status , Quality of Life/psychology , Adult , China , Disease-Free Survival , Female , Humans , Middle Aged , Prospective Studies , Social Adjustment
6.
J Am Coll Health ; 69(7): 783-790, 2021 10.
Article in English | MEDLINE | ID: mdl-31944901

ABSTRACT

OBJECTIVE: The purpose of this study was to explore (a) current utilization rates of university mental health services among American Indian/Alaskan Native/Native Hawaiian (AI/AN/NH) student veterans and (b) predictors of mental health service utilization among AI/AN student veterans. Participants: Data for this cross-sectional study were obtained from the American College Health Association (ACHA)'s 2011-2014 National College Health Assessment II (n = 103). Methods: University mental health service utilization rates were calculated as a percentage for AI/AN/NH student veterans. Multivariable logistic regression was used to determine predictors of mental health service utilization. Results: Results showed that 14% of AI/AN/NH student veterans have used university mental health services. Predictors of mental health service utilization in this population included financial stress, lack of deployment during service, suicidal ideation, and a diagnosis of depression, model χ2 (13) = 162. 128, p < 0.001, Nagelkerke R2 = 0.130. Conclusion: This research identified gaps in service provision for AI/AN service member and veteran students on college campuses and provided possible models for intervention development.


Subject(s)
Veterans , Cross-Sectional Studies , Humans , Students , United States , Universities , American Indian or Alaska Native
7.
Data Brief ; 30: 105421, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32215313

ABSTRACT

Chemotherapy-induced nausea and vomiting (CINV) are highly distressing symptoms for cancer patients undergoing cytotoxic chemotherapy. This dataset was obtained from a homogenous group of Chinese breast cancer patients who were uniformly planned to receive a highly emetogenic (neo)adjuvant chemotherapy regimen, consisting of doxorubicin and cyclophosphamide (commonly known as AC). Patients were being randomized to one of the two antiemetic regimens: aprepitant, ondansetron and dexamethasone with (the Olanzapine arm) or without olanzapine (the Standard arm). Patients underwent self-reported diaries and questionnaires to record their nausea and vomiting symptoms, use of rescue medication as well as their quality of life (QOL). The primary and secondary endpoints have focused on efficacy analysis during the first cycle of AC chemotherapy; the results have been reported in The Breast [1]. In this Data in Brief article, we provide outcome of the analysis of data collected during multiple cycles of chemotherapy. The data reported here include the proportion of patients with "Complete Response", "Complete Protection" and "Total Control" of emesis in the acute (0-24 h), delayed (24-120 h) and overall periods (0-120 h), as well as QOL data during all the 4 cycles of AC.

8.
FASEB J ; 34(2): 2198-2212, 2020 02.
Article in English | MEDLINE | ID: mdl-31907988

ABSTRACT

Clostridioides difficile (formerly Clostridium difficile; C difficile), the leading cause of nosocomial antibiotic-associated colitis and diarrhea in the industrialized world, triggers colonic disease through the release two toxins, toxin A (TcdA) and toxin B (TcdB), glucosyltransferases that modulate monomeric G-protein function and alter cytoskeletal function. The initial degree of the host immune response to C difficile and its pathogenic toxins is a common indicator of disease severity and infection recurrence. Thus, targeting the intestinal inflammatory response during infection could significantly decrease disease morbidity and mortality. In the current study, we sought to interrogate the influence of the pregnane X receptor (PXR), a modulator of xenobiotic and detoxification responses, which can sense and respond to microbial metabolites and modulates inflammatory activity, during exposure to TcdA and TcdB. Following intrarectal exposure to TcdA/B, PXR-deficient mice (Nr1i2-/- ) exhibited reduced survival, an effect that was associated with increased levels of innate immune cell influx. This exacerbated response was associated with a twofold increase in the expression of Tlr4. Furthermore, while broad-spectrum antibiotic treatment (to deplete the intestinal microbiota) did not alter the responses in Nr1i2-/- mice, blocking TLR4 signaling significantly reduced TcdA/B-induced disease severity and immune responses in these mice. Lastly, to assess the therapeutic potential of targeting the PXR, we activated the PXR with pregnenolone 16α-carbonitrile (PCN) in wild-type mice, which greatly reduced the severity of TcdA/B-induced damage and intestinal inflammation. Taken together, these data suggest that the PXR plays a role in the host's response to TcdA/B and may provide a novel target to dampen the inflammatory tissue damage in C difficile infections.


Subject(s)
Bacterial Proteins/metabolism , Bacterial Toxins/metabolism , Clostridioides difficile , Enterocolitis, Pseudomembranous/metabolism , Enterotoxins/metabolism , Pregnane X Receptor/metabolism , Signal Transduction , Animals , Clostridioides difficile/metabolism , Clostridioides difficile/pathogenicity , Enterocolitis, Pseudomembranous/genetics , Enterocolitis, Pseudomembranous/pathology , Inflammation/genetics , Inflammation/metabolism , Inflammation/pathology , Mice , Mice, Knockout , Pregnane X Receptor/genetics , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism
9.
J Pharmacol Exp Ther ; 370(1): 44-53, 2019 07.
Article in English | MEDLINE | ID: mdl-31004077

ABSTRACT

The pregnane X receptor (PXR) is a ligand-activated nuclear receptor that acts as a xenobiotic sensor, responding to compounds of foreign origin, including pharmaceutical compounds, environmental contaminants, and natural products, to induce transcriptional events that regulate drug detoxification and efflux pathways. As such, the PXR is thought to play a key role in protecting the host from xenobiotic exposure. More recently, the PXR has been reported to regulate the expression of innate immune receptors in the intestine and modulate inflammasome activation in the vasculature. In the current study, we report that activation of the PXR in primed macrophages triggers caspase-1 activation and interleukin-1ß release. Mechanistically, we show that this response is nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain-containing 3-dependent and is driven by the rapid efflux of ATP and P2X purinoceptor 7 activation following PXR stimulation, an event that involves pannexin-1 gating, and is sensitive to inhibition of Src-family kinases. Our findings identify a mechanism whereby the PXR drives innate immune signaling, providing a potential link between xenobiotic exposure and the induction of innate inflammatory responses.


Subject(s)
Adenosine Triphosphate/metabolism , Inflammasomes/metabolism , Macrophages/drug effects , Macrophages/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Pregnane X Receptor/metabolism , Animals , Caspase 1/metabolism , Cell Line, Tumor , Connexins/metabolism , Enzyme Activation/drug effects , Humans , Interleukin-1beta/metabolism , Kinetics , Ligands , Mice , Nerve Tissue Proteins/metabolism , Pregnane X Receptor/agonists , Receptors, Purinergic P2X7/metabolism , src-Family Kinases/metabolism
10.
Eur J Pharmacol ; 815: 501-511, 2017 Nov 15.
Article in English | MEDLINE | ID: mdl-29031898

ABSTRACT

Conflicting data exist on the effect of ginsenosides on transactivation of human glucocorticoid receptor α (herein referred to as glucocorticoid receptor), and relatively little is known regarding the effect of these chemicals on transrepression of this receptor. We investigated the effect of 20(S)-protopanaxadiol (PPD), PPD-type ginsenosides (Rb1, Rb2, Rc, Rd, Rh2, and Compound K), 20(S)-protopanaxatriol (PPT), and PPT-type ginsenosides (Re, Rf, Rg1, and Rh1) on glucocorticoid receptor binding, transactivation, and transrepression. Each ginsenoside was less efficacious than dexamethasone (positive control) in binding to the ligand-binding domain of glucocorticoid receptor. Among the ginsenosides investigated, Rh2 had the smallest IC50 value (15 ± 1µM), whereas it was 0.02 ± 0.01µM for dexamethasone. In contrast to dexamethasone, none of the ginsenosides influenced glucocorticoid receptor transactivation or transrepression in LS180 human colorectal adenocarcinoma cells, as assessed in a dual-luciferase reporter gene assay. Rh2 did not affect the endogenous mRNA level of tyrosine aminotransferase (marker for glucocorticoid receptor transactivation) or corticosteroid-binding globulin (marker for glucocorticoid receptor transrepression) in HepG2 human hepatocellular carcinoma cells. This chemical also did not alter the response by a glucocorticoid receptor agonist (dexamethasone or Compound A) in the dual-luciferase reporter gene assay or target gene expression assay. In conclusion, ginsenosides were less efficacious and less potent than dexamethasone in binding to the ligand-binding domain of glucocorticoid receptor. The number of glycosylated groups was associated with a decrease in receptor binding potency. PPD-type and PPT-type ginsenosides are not modulators of glucocorticoid receptor transactivation or transrepression in LS180 and HepG2 cells.


Subject(s)
Ginsenosides/metabolism , Ginsenosides/pharmacology , Receptors, Glucocorticoid/genetics , Receptors, Glucocorticoid/metabolism , Transcriptional Activation/drug effects , Hep G2 Cells , Humans , Ligands , Protein Binding , Protein Domains , Receptors, Glucocorticoid/chemistry
11.
Mol Pharmacol ; 92(1): 48-56, 2017 07.
Article in English | MEDLINE | ID: mdl-28408657

ABSTRACT

Small noncoding microRNAs act as post-transcriptional regulators of gene expression involved in diverse biologic functions. Pregnane X receptor (PXR, NR1I2), a member of the superfamily of nuclear receptors, is a transcription factor governing the transport and biotransformation of various drugs and other chemicals. In the present study, we identified a specific microRNA (miR) involved in regulating the expression and functionality of human PXR (hPXR). According to bioinformatics analysis employing three commonly used algorithms (TargetScan, miRanda, and DIANA-microT-CDS), miR-18a-5p was predicted to be the top candidate microRNA regulator of hPXR. Consequently, this microRNA was selected for detailed experimental investigation. As shown in cell-based dual-luciferase reporter gene assays, functional interaction occurred between miR-18a-5p and the microRNA recognition element of miR-18a-5p in the 3'-untranslated region of hPXR mRNA. Transfection of LS180 human colorectal adenocarcinoma cells with an miR-18a-5p mimic decreased hPXR mRNA and protein expression, whereas transfection of LS180 cells with an miR-18a-5p inhibitor increased hPXR mRNA and protein expression. The decrease in hPXR expression by the miR-18a-5p mimic was associated with a reduction in the extent of hPXR target gene (CYP3A4) induction by rifampin and rilpivirine. Treatment of untransfected LS180 cells with either of these hPXR agonists decreased endogenous expression of miR-18a-5p, and this preceded the onset of CYP3A4 induction. In conclusion, miR-18a-5p is a negative regulator of hPXR expression and the hPXR agonists rifampin and rilpivirine are chemical suppressors of miR-18a-5p expression.


Subject(s)
MicroRNAs/antagonists & inhibitors , MicroRNAs/biosynthesis , Receptors, Steroid/antagonists & inhibitors , Receptors, Steroid/biosynthesis , Rifampin/pharmacology , Rilpivirine/pharmacology , Cell Line, Tumor , Dose-Response Relationship, Drug , Gene Expression , Humans , Luciferases, Renilla , MicroRNAs/genetics , Pregnane X Receptor , Receptors, Steroid/agonists , Reverse Transcriptase Inhibitors/pharmacology
12.
J Pharmacol Exp Ther ; 359(1): 91-101, 2016 10.
Article in English | MEDLINE | ID: mdl-27440420

ABSTRACT

The inflammatory bowel diseases (IBDs) are chronic inflammatory disorders with a complex etiology. IBD is thought to arise in genetically susceptible individuals in the context of aberrant interactions with the intestinal microbiota and other environmental risk factors. Recently, the pregnane X receptor (PXR) was identified as a sensor for microbial metabolites, whose activation can regulate the intestinal epithelial barrier. Mutations in NR1I2, the gene that encodes the PXR, have been linked to IBD, and in animal models, PXR deletion leads to barrier dysfunction. In the current study, we sought to assess the mechanism(s) through which the PXR regulates barrier function during inflammation. In Caco-2 intestinal epithelial cell monolayers, tumor necrosis factor-α/interferon-γ exposure disrupted the barrier and triggered zonula occludens-1 relocalization, increased expression of myosin light-chain kinase (MLCK), and activation of c-Jun N-terminal kinase 1/2 (JNK1/2). Activation of the PXR [rifaximin and [[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]ethenylidene]bis-phosphonic acid tetraethyl ester (SR12813); 10 µM] protected the barrier, an effect that was associated with attenuated MLCK expression and JNK1/2 activation. In vivo, activation of the PXR [pregnenolone 16α-carbonitrile (PCN)] attenuated barrier disruption induced by toll-like receptor 4 activation in wild-type, but not Pxr-/-, mice. Furthermore, PCN treatment protected the barrier in the dextran-sulfate sodium model of experimental colitis, an effect that was associated with reduced expression of mucosal MLCK and phosphorylated JNK1/2. Together, our data suggest that the PXR regulates the intestinal epithelial barrier during inflammation by modulating cytokine-induced MLCK expression and JNK1/2 activation. Thus, targeting the PXR may prove beneficial for the treatment of inflammation-associated barrier disruption in the context of IBD.


Subject(s)
Cytokines/pharmacology , Gene Expression Regulation, Enzymologic/drug effects , Intestinal Mucosa/drug effects , Mitogen-Activated Protein Kinase 8/metabolism , Mitogen-Activated Protein Kinase 9/metabolism , Myosin-Light-Chain Kinase/metabolism , Receptors, Steroid/metabolism , Animals , Caco-2 Cells , Colitis/chemically induced , Colitis/metabolism , Colitis/pathology , Dextran Sulfate/pharmacology , Enzyme Activation/drug effects , Hep G2 Cells , Humans , Inflammation/metabolism , Inflammation/pathology , Interferon-gamma/pharmacology , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Male , Mice , NF-kappa B/metabolism , Pregnane X Receptor , Signal Transduction/drug effects , Toll-Like Receptor 4/metabolism , Tumor Necrosis Factor-alpha/pharmacology
13.
Behav Processes ; 128: 1-8, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27038859

ABSTRACT

Melatonin is a hormone rhythmically secreted at night by the pineal gland in vertebrates. In diurnal mammals, melatonin is present during the inactive phase of the rest/activity cycle, and in primates it directly facilitates sleep and decreases body temperature. However, the role of the pineal gland for the promotion of sleep at night has not yet been studied in non-primate diurnal mammalian species. Here, the authors directly examined the hypothesis that the pineal gland contributes to diurnality in Nile grass rats by decreasing activity and increasing sleep at night, and that this could occur via effects on circadian mechanisms or masking, or both. Removing the pineal gland had no effect on the hourly distribution of activity across a 12:12 light-dark (LD) cycle or on the patterns of sleep-like behavior at night. Masking effects of light at night on activity were also not significantly different in pinealectomized and control grass rats, as 1h pulses of light stimulated increases in activity of sham and pinealectomized animals to a similar extent. In addition, the circadian regulation of activity was unaffected by the surgical condition of the animals. Our results suggest that the pineal gland does not contribute to diurnality in the grass rat, thus highlighting the complexity of temporal niche transitions. The current data raise interesting questions about how and why genetic and neural mechanisms linking melatonin to sleep regulatory systems might vary among mammals that reached a diurnal niche via parallel and independent pathways.


Subject(s)
Circadian Rhythm/physiology , Muridae/physiology , Pineal Gland/physiology , Sleep/physiology , Animals , Female , Light , Motor Activity/physiology , Photoperiod , Pineal Gland/surgery
14.
J Steroid Biochem Mol Biol ; 163: 59-67, 2016 10.
Article in English | MEDLINE | ID: mdl-27041117

ABSTRACT

It has been reported that quercetin is an activator of rat vitamin D receptor (rVDR). However, the conclusion was based on experiments performed without all the appropriate control groups, raising the possibility of a false-positive finding. Furthermore, distinct differences exist in the chemical structures of quercetin and 1α,25-dihydroxyvitamin D3, which is a prototypic agonist of VDR. Therefore, we investigated systematically whether quercetin and other flavonols are agonists of rVDR, mouse VDR (mVDR), or human VDR (hVDR). Quercetin, 3-hydroxyflavone, galangin, datiscetin, kaempferol, morin, isorhamnetin, tamarixetin, myricetin, and syringetin did not activate rVDR, mVDR, or hVDR in HEK-293 and HepG2 cells transfected with the corresponding receptor expression plasmid and either the secreted phosphoprotein 1 (Spp1) or cytochrome P450 24A1 (CYP24A1) reporter plasmid, when compared to the respective empty vector control group transfected with one or the other reporter plasmid and treated with one of the flavonols. Control analysis indicated that lithocholic acid and 1α,25-dihydroxyvitamin D3, but not rifampicin, activated rVDR, mVDR, and hVDR. As shown in transfected HEK293 and HepG2 cells, the flavonols did not influence hVDR ligand binding domain transactivation, steroid receptor coactivator-1 recruitment, or hVDR target gene expression (transient receptor potential cation channel 6 and CYP24A1) in hVDR-expressing Caco-2 or LS180 cells. The cumulative data from the cell-based experiments were corroborated by results obtained from molecular docking analysis. In conclusion, quercetin, 3-hydroxyflavone, galangin, datiscetin, kaempferol, morin, isorhamnetin, tamarixetin, myricetin, and syringetin are not agonists of rVDR, mVDR, or hVDR, as judged by cell-based and in silico evidence.


Subject(s)
Calcitriol/pharmacology , Gene Expression Regulation/drug effects , Quercetin/pharmacology , Receptors, Calcitriol/genetics , Animals , Caco-2 Cells , Disaccharides/pharmacology , Flavonoids/pharmacology , HEK293 Cells , Hep G2 Cells , Humans , Kaempferols/pharmacology , Mice , Molecular Docking Simulation , Osteopontin/genetics , Osteopontin/metabolism , Quercetin/analogs & derivatives , Receptors, Calcitriol/agonists , Receptors, Calcitriol/metabolism , Structure-Activity Relationship , Transgenes , Vitamin D3 24-Hydroxylase/genetics , Vitamin D3 24-Hydroxylase/metabolism
15.
Curr Oncol Rep ; 18(1): 2, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26694923

ABSTRACT

Nausea and vomiting are common in cancer patients. The most common cause of nausea and vomiting is the administration of cytotoxic chemotherapy. Apart from chemotherapy-induced nausea and vomiting (CINV), biological agents may also cause these symptoms. In this review, discussion will be focused on management of nausea and vomiting due to antineoplastic therapies. The cornerstone of effective management of nausea and vomiting secondary to these antineoplastic drugs is the prevention with the use of appropriate guideline-directed combination antiemetic regimen. Type 3 serotonin receptor antagonists (5HT3RAs), neurokinin-1 receptor antagonists (NK1RAs), and dexamethasone are the backbone antiemetic drugs. In recent years, newer drugs and preparations have been introduced for clinical use and include second-generation 5HT3RA, palonosetron; granisetron transdermal patch; the recently introduced NK1RA rolapitant; and the novel oral combined drug NEPA (netupitant plus palonosetron); and last but not least, the atypical antipsychotic olanzapine.


Subject(s)
Antiemetics/therapeutic use , Antineoplastic Agents/adverse effects , Dexamethasone/therapeutic use , Nausea/chemically induced , Nausea/drug therapy , Neoplasms/drug therapy , Vomiting/drug therapy , Drug Administration Schedule , Drug Therapy, Combination , Guideline Adherence , Humans , Neoplasms/complications , Neurokinin-1 Receptor Antagonists/therapeutic use , Practice Guidelines as Topic , Serotonin 5-HT3 Receptor Antagonists/therapeutic use , Treatment Outcome , Vomiting/chemically induced
16.
J Affect Disord ; 192: 8-10, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26707346

ABSTRACT

BACKGROUND: Some studies suggest that people who self-cut have a higher risk of suicide than those who self-poison. Self-cutting ranges from superficial wrist cutting to severe self-injury involving areas such as the chest, abdomen and neck which can be life threatening. This study aimed to investigate whether the site of self-cutting was associated with risk of subsequent suicide. METHODS: We followed-up 3928 people who presented to hospital following self-harm between September 2010 and December 2013 in a prospective cohort study based on the Bristol Self-harm Surveillance Register. Demographic information from these presentations was linked with coroner's data to identify subsequent suicides. RESULTS: People who presented with self-cutting to areas other than the arm/wrist were at increased risk of suicide compared to those who self-poisoned (HR 4.31, 95% CI 1.27-14.63, p=0.029) and this increased risk remained after controlling for age, sex, history of previous self-harm and psychiatric diagnosis (HR 4.46, 95% CI 1.50-13.25, p<0.001). We observed no such increased risk in people presenting with cutting to the arm/wrist. LIMITATIONS: These data represent the experience of one city in the UK and may not be generalisable outside of this context. Furthermore, as suicide is a rare outcome the precision of our estimates is limited. CONCLUSIONS: Site of self-injury may be an important indicator of subsequent suicide risk.


Subject(s)
Poisoning/psychology , Self-Injurious Behavior/psychology , Suicide/psychology , Wounds, Penetrating/psychology , Adolescent , Adult , Aged , Aged, 80 and over , England , Female , Humans , Male , Mental Disorders , Middle Aged , Prospective Studies , Risk Factors , Wrist Injuries/psychology , Young Adult
17.
Pharmacol Res ; 100: 64-72, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26238175

ABSTRACT

Pregnane X receptor (PXR; NR1I2) is a member of the superfamily of nuclear receptors that regulates the expression of genes involved in various biological processes, including drug transport and biotransformation. In the present study, we investigated the effect of 3-hydroxyflavone and its structurally-related analogues on PXR activity. 3-Hydroxyflavone, galangin, kaempferol, querceetin, isorhamnetin, and tamarixetin, but not but not datiscetin, morin, myricetin, or syringetin, activated mouse PXR, as assessed in a cell-based reporter gene assay. By comparison, 3-hydroxyflavone activated rat PXR, whereas 3-hydroxyflavone, galangin, quercetin, isorhamnetin, and tamarixetin activated human PXR (hPXR). A time-resolved fluorescence resonance energy transfer competitive ligand-binding assay showed binding to the ligand-binding domain of hPXR by 3-hydroxyflavone, galangin, quercetin, isorhamnetin, and tamarixetin. 3-Hydroxyflavone and galangin, but not quercetin, isorhamnetin, or tamarixetin, recruited steroid receptor coactivator (SRC)-1, SRC-2, and SRC-3 to hPXR. In LS180 human colon adenocarcinoma cells, 3-hydroxyflavone, quercetin, and tamarixetin increased CYP3A4, CYP3A5, and ABCB1 mRNA expression, whereas galangin and isorhamnetin increased CYP3A4 and ABCB1 but not CYP3A5 mRNA expression. Datiscetin, kaempferol, morin, myricetin, and syringetin did not attenuate the extent of hPXR activation by rifampicin, suggesting they are not hPXR antagonists. Overall, flavonols activate PXR in an analogue-specific and species-dependent manner. Substitution at the C2' or C5' position of 3-hydroxyflavone with a hydroxyl or methoxy group rendered it incapable of activating hPXR. Understanding the structure-activity relationship of flavonols in hPXR activation may facilitate nutraceutical development efforts in the treatment of PXR-associated intestinal diseases, such as inflammatory bowel disease.


Subject(s)
Flavonoids/pharmacology , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/metabolism , Receptors, Steroid/metabolism , Cell Line, Tumor , Genes, Reporter/drug effects , Hep G2 Cells , Humans , Ligands , Pregnane X Receptor , RNA, Messenger/drug effects , Structure-Activity Relationship
18.
Br J Pharmacol ; 172(5): 1263-76, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25363652

ABSTRACT

BACKGROUND AND PURPOSE: Rilpivirine and etravirine are second-generation non-nucleoside reverse transcriptase inhibitors (NNRTIs) indicated for the treatment of HIV/AIDS. The constitutive androstane receptor (CAR) regulates the expression of genes involved in various biological processes, including the transport and biotransformation of drugs. We investigated the effect of rilpivirine and etravirine on the activity of the wild-type human CAR (hCAR-WT) and its hCAR-SV23 and hCAR-SV24 splice variants, and compared it with first-generation NNRTIs (efavirenz, nevirapine, and delavirdine). EXPERIMENTAL APPROACH: Receptor activation, ligand-binding domain (LBD) transactivation, and co-activator recruitment were investigated in transiently transfected, NNRTI-treated HepG2 cells. Nuclear translocation of green fluorescent protein-tagged hCAR-WT and CYP2B6 gene expression were assessed in NNRTI-treated human hepatocytes. KEY RESULTS: Rilpivirine and etravirine activated hCAR-WT, but not hCAR-SV23 or hCAR-SV24, and without transactivating the LBD or recruiting steroid receptor coactivators SRC-1, SRC-2, or SRC-3. Among the first-generation NNRTIs investigated, only efavirenz activated hCAR-WT, hCAR-SV23, and hCAR-SV24, but none of them transactivated the LBD of these receptors or substantively recruited SRC-1, SRC-2, or SRC-3. Rilpivirine, etravirine, and efavirenz triggered nuclear translocation of hCAR-WT and increased hCAR target gene (CYP2B6) expression. CONCLUSION AND IMPLICATIONS: NNRTIs activate hCAR-WT, hCAR-SV23, and hCAR-SV24 in a drug-specific and isoform-selective manner. The activation occurs by a mechanism that does not appear to involve binding to the LBD or recruitment of SRC-1, SRC-2, or SRC-3.


Subject(s)
Alternative Splicing/drug effects , Alternative Splicing/genetics , Pyridazines/pharmacology , Receptors, Cytoplasmic and Nuclear/agonists , Receptors, Cytoplasmic and Nuclear/genetics , Reverse Transcriptase Inhibitors/pharmacology , Rilpivirine/pharmacology , Adolescent , Adult , Aged , Constitutive Androstane Receptor , Cytochrome P-450 CYP2B6/genetics , Cytochrome P-450 CYP2B6/metabolism , Dose-Response Relationship, Drug , Female , Hep G2 Cells , Hepatocytes/drug effects , Hepatocytes/metabolism , Humans , Male , Molecular Structure , Nitriles , Pyridazines/chemistry , Pyrimidines , Receptors, Cytoplasmic and Nuclear/metabolism , Reverse Transcriptase Inhibitors/chemistry , Rilpivirine/chemistry , Structure-Activity Relationship , Tumor Cells, Cultured , Young Adult
19.
Drug Metab Dispos ; 42(11): 1834-42, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25147275

ABSTRACT

Acyl glucuronides are reactive electrophilic metabolites implicated in the toxicity of carboxylic acid drugs. Valproyl 1-O-ß-acyl glucuronide (VPA-G), which is a major metabolite of valproic acid (VPA), has been linked to the development of oxidative stress in VPA-treated rats. However, relatively little is known about the toxicity of in situ generated VPA-G and its contribution to VPA hepatotoxicity. Therefore, we investigated the effects of modulating the in situ formation of VPA-G on lactate dehydrogenase (LDH) release (a marker of necrosis), BODIPY 558/568 C12 accumulation (a marker of steatosis), and cellular glutathione (GSH) content in VPA-treated sandwich-cultured rat hepatocytes. VPA increased LDH release and BODIPY 558/568 C12 accumulation, whereas it had little or no effect on total GSH content. Among the various uridine 5'-diphospho-glucuronosyltransferase inducers evaluated, ß-naphthoflavone produced the greatest increase in VPA-G formation. This was accompanied by an attenuation of the increase in BODIPY 558/568 C12 accumulation, but did not affect the change in LDH release or total GSH content in VPA-treated hepatocytes. Inhibition of in situ formation of VPA-G by borneol was not accompanied by substantive changes in the effects of VPA on any of the toxicity markers. In a comparative study, in situ generated diclofenac glucuronide was not toxic to rat hepatocytes, as assessed using the same chemical modulators, thereby demonstrating the utility of the sandwich-cultured rat hepatocyte model. Overall, in situ generated VPA-G was not toxic to sandwich-cultured rat hepatocytes, suggesting that VPA glucuronidation per se is not expected to be a contributing mechanism for VPA hepatotoxicity.


Subject(s)
Glucuronides/metabolism , Hepatocytes/drug effects , Valproic Acid/toxicity , Animals , Camphanes/pharmacology , Cells, Cultured , Hepatocytes/enzymology , Hepatocytes/metabolism , L-Lactate Dehydrogenase/metabolism , Male , Rats , Rats, Sprague-Dawley , beta-Naphthoflavone/pharmacology
20.
Toxicol Appl Pharmacol ; 277(2): 221-30, 2014 Jun 01.
Article in English | MEDLINE | ID: mdl-24721719

ABSTRACT

The naturally occurring SV23 splice variant of human constitutive androstane receptor (hCAR-SV23) is activated by di-(2-ethylhexyl)phthalate (DEHP), which is detected as a contaminant in fetal bovine serum (FBS). In our initial experiment, we compared the effect of dialyzed FBS, charcoal-stripped, dextran-treated FBS (CS-FBS), and regular FBS on the basal activity and ligand-activation of hCAR-SV23 in a cell-based reporter gene assay. In transfected HepG2 cells cultured in medium supplemented with 10% FBS, basal hCAR-SV23 activity varied with the type of FBS (regular>dialyzed>CS). DEHP increased hCAR-SV23 activity when 10% CS-FBS, but not regular FBS or dialyzed FBS, was used. With increasing concentrations (1-10%) of regular FBS or CS-FBS, hCAR-SV23 basal activity increased, whereas in DEHP-treated cells, hCAR-SV23 activity remained similar (regular FBS) or slightly increased (CS-FBS). Subsequent experiments identified a serum-free culture condition to detect DEHP activation of hCAR-SV23. Under this condition, artemisinin, artemether, and arteether increased hCAR-SV23 activity, whereas they decreased it in cells cultured in medium supplemented with 10% regular FBS. By comparison, FBS increased the basal activity of the wild-type isoform of hCAR (hCAR-WT), whereas it did not affect the basal activity of the SV24 splice variant (hCAR-SV24) or ligand activation of hCAR-SV24 and hCAR-WT by 6-(4-chlorophenyl)imidazo[2,1-b][1,3]thiazole-5-carbaldehyde O-(3,4-dichlorobenzyl)oxime (CITCO). The use of serum-free culture condition was suitable for detecting CITCO activation of hCAR-WT and hCAR-SV24. In conclusion, FBS leads to erroneous classification of pharmacological ligands of hCAR-SV23 in cell-based assays, but investigations on functional ligands of hCAR isoforms can be conducted in serum-free culture condition.


Subject(s)
Artemisinins/pharmacology , Biological Assay/methods , Receptors, Androgen/drug effects , Serum/metabolism , Artemether , Cell Culture Techniques , Cell Survival/drug effects , Dose-Response Relationship, Drug , Genes, Reporter , Hep G2 Cells , Humans , Ligands , Protein Isoforms , Receptors, Androgen/genetics , Receptors, Androgen/metabolism , Reproducibility of Results , Time Factors , Transfection
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