AMPA induced cognitive impairment in rats: Establishing the role of endoplasmic reticulum stress inhibitor, 4-PBA.

Glutamate excitotoxicity and endoplasmic reticulum (ER) recently have been found to be instrumental in the pathogenesis of various neurodegenerative diseases. However, the paucity of literature deciphering the inter-linkage among glutamate receptors, behavioral alterations, and ER demands thorough exploration. Reckoning the aforesaid concerns, a prospective study was outlined to delineate the influence of ER stress inhibition via 4-phenylbutyric acid (PBA) on α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) excitotoxicity-induced behavioral aspects and possible ER stress-glutamate linkage. Male SD rats were randomly divided into four groups namely sham (surgical control+vehicle, group 1), AMPA-induced excitotoxic group 2 receive a single intra-hippocampal injection of 10 mM AMPA, group 3 received AMPA along with PBA (i.p, 100 mg/kg body weight) for 15 days, and group 4 received PBA alone. Behavioral analyses were performed prior to the sacrifice of animals and hippocampus was extracted thereafter for further analysis. AMPA-induced excitotoxicity exhibited significant impairment of locomotion as well as cognitive functions. The levels of neurotransmitters such as dopamine, homo vanillic acid (HVA), norepinephrine, and serotonin were reduced accompanied by reduced expression of GLUR1 and GLUR4 (glutamate receptor) as well as loss of neurons in different layers of hippocampus. ER stress markers were upregulated upon AMPA excitotoxicity. However, chemical chaperone PBA supplementation remarkably mitigated the behavioral alterations along with expression of glutamate and ER stress intermediates/markers in AMPA excitotoxic animals. Therefore, the present exploration convincingly emphasizes the significance of ER stress and its inhibition via PBA in combating cognitive impairment as well as improving locomotion in excitotoxic animals.

WTAP promotes myocardial ischemia/reperfusion injury by increasing endoplasmic reticulum stress via regulating m6A modification of ATF4 mRNA.

Myocardial infarction (MI) is one of the leading causes of death. Wilms' tumor 1-associating protein (WTAP), one of the components of the m6A methyltransferase complex, has been shown to affect gene expression via regulating mRNA modification. Although WTAP has been implicated in various diseases, its role in MI is unclear. In this study, we found that hypoxia/reoxygenation (H/R) time-dependently increased WTAP expression, which in turn promoted endoplasmic reticulum (ER) stress and apoptosis, in human cardiomyocytes (AC16). H/R effects on ER stress and apoptosis were all blocked by silencing of WTAP, promoted by WTAP overexpression, and ameliorated by administration of ER stress inhibitor, 4-PBA. We then investigated the underlying molecular mechanism and found that WTAP affected m6A methylation of ATF4 mRNA to regulate its expression, and that the inhibitory effects of WTAP on ER stress and apoptosis were ATF4 dependent. Finally, WTAP's effects on myocardial I/R injury were confirmed in vivo. WTAP promoted myocardial I/R injury through promoting ER stress and cell apoptosis by regulating m6A modification of ATF4 mRNA. These findings highlight the importance of WTAP in I/R injury and provide new insights into therapeutic strategies for MI.

Immortalized canine adipose-derived mesenchymal stem cells alleviate gentamicin-induced acute kidney injury by inhibiting endoplasmic reticulum stress in mice and dogs.

Adipose-derived mesenchymal stem cells have been used to treat acute kidney injury (AKI). The role of endoplasmic reticulum (ER) stress in AKI treatment with canine adipose-derived mesenchymal stem cells (cADSCs) remains unknown. This study intended to investigate the therapeutic effects of cADSCs cultured in different media on AKI in mice and dogs and reveal the role of ER stress in this process. The mice were divided into two branches: a control group and a gentamicin induced group (this group treated with low-serum ADSC or high-serum ADSC or 4-phenylbutyric acid (4-PBA)). The dogs were divided into control, model, and cell-injected groups. To suppress ER stress, mice were simultaneously treated with 4-PBA. The results showed there were improvements in renal function and tissue damage and a corresponding decrease in ER stress in the kidneys of the mice that received cell injection. However, the cells cultured with 2% FBS showed a better growth state and resulted in lower ER stress levels in treated kidneys. In the 4-PBA-treated group, ER stress was suppressed, and there was corresponding kidney injury recovery. Similarly, both kidney damage and ER stress were alleviated after AKI dogs were injected with the cells. Our findings reveal that both allogeneic and xenogeneic cADSCs were effective treatments for AKI by inhibiting ER stress. These results also provide evidence for a new clinical therapy for acute renal disease in pets.

Primary Care Management of Upper Respiratory Infections in the Women's Health Care Setting.

Upper respiratory infections (URIs) are the most common reason for which individuals seek health care services in the outpatient clinical setting. This case report describes the clinical presentation and management of a woman with a URI. The signs and symptoms of URIs, physical examination, differential diagnoses, and treatment plan options available in the ambulatory care setting are reviewed. Current evidence-based guidelines are discussed, and recommendations for clinical practice are reviewed. Discussion of the incidental treatment of URIs in the specialty care setting is also addressed.

Chemical chaperone 4-phenylbutylate reduces mutant protein accumulation in the endoplasmic reticulum of arginine vasopressin neurons in a mouse model for familial neurohypophysial diabetes insipidus.

Familial neurohypophysial diabetes insipidus (FNDI), characterized by progressive polyuria and loss of arginine vasopressin (AVP) neurons, is an autosomal dominant disorder caused by AVP gene mutations. Our previous studies with FNDI model mice demonstrated that mutant proteins accumulated in the endoplasmic reticulum (ER) of AVP neurons. Here, we examined therapeutic effects of the chemical chaperone 4-phenylbutylate (4-PBA) in FNDI mice. Treatment with 4-PBA reduced mutant protein accumulation in the ER of FNDI mice and increased AVP release, leading to reduced urine volumes. Furthermore, AVP neuron loss under salt loading was attenuated by 4-PBA treatment. These data suggest that 4-PBA ameliorated mutant protein accumulation in the ER of AVP neurons and thereby prevented FNDI phenotype progression.

4-PBA improves lithium-induced nephrogenic diabetes insipidus by attenuating ER stress.

Endoplasmic reticulum (ER) stress has been implicated in some types of glomerular and tubular disorders. The objectives of this study were to elucidate the role of ER stress in lithium-induced nephrogenic diabetes insipidus (NDI) and to investigate whether attenuation of ER stress by 4-phenylbutyric acid (4-PBA) improves urinary concentrating defect in lithium-treated rats. Wistar rats received lithium (40 mmol/kg food), 4-PBA (320 mg/kg body wt by gavage every day), or no treatment (control) for 2 wk, and they were dehydrated for 24 h before euthanasia. Lithium treatment resulted in increased urine output and decreased urinary osmolality, which was significantly improved by 4-PBA. 4-PBA also prevented reduced protein expression of aquaporin-2 (AQP2), pS256-AQP2, and pS261-AQP2 in the inner medulla of kidneys from lithium-treated rats after 24-h dehydration. Lithium treatment resulted in increased expression of ER stress markers in the inner medulla, which was associated with dilated cisternae and expansion of ER in the inner medullary collecting duct (IMCD) principal cells. Confocal immunofluorescence studies showed colocalization of a molecular chaperone, binding IgG protein (BiP), with AQP2 in principal cells. Immunohistochemistry demonstrated increased intracellular expression of BiP and decreased AQP2 expression in IMCD principal cells of kidneys from lithium-treated rats. 4-PBA attenuated expression of ER stress markers and recovered ER morphology. In IMCD suspensions isolated from lithium-treated rats, 4-PBA incubation was also associated with increased AQP2 expression and ameliorated ER stress. In conclusion, in experimental lithium-induced NDI, 4-PBA improved the urinary concentrating defect and increased AQP2 expression, likely via attenuating ER stress in IMCD principal cells.

Inhibition of cough-reflex sensitivity by benzonatate and guaifenesin in acute viral cough.

Acute cough due to viral upper respiratory tract infection (URI) is the most common form of cough and accounts for tremendous expenditure on prescription and non-prescription cough products worldwide. However, few agents have been shown in properly conducted clinical trials to be effective for cough due to URI. The present study evaluated the effect of benzonatate 200mg (B), guaifenesin 600 mg (G), their combination (B+G), and placebo (P) on capsaicin-induced cough in 30 adult nonsmokers with acute URI. On 3 separate days within a 7-day period, 1h after ingesting randomly assigned study drug in a double-blind fashion, subjects underwent capsaicin cough challenge testing, which involved inhalation of incremental doubling concentrations of capsaicin until the concentration of capsaicin inducing 5 or more coughs (C(5)) was attained. Each subject received 3 of 4 possible study drugs. G (p=0.01) but not B (p=NS) inhibited cough-reflex sensitivity (log C(5)) relative to P. The combination of B+G suppressed capsaicin-induced cough to a greater degree than B alone (p<0.001) or G alone (p=0.008). The mechanism by which the combination of B+G causes a potentiation of antitussive effect remains to be elucidated. Our results suggest that B+G may be an effective therapy for acute cough due to the common cold (URI).

ATP-sensitive potassium channel openers and 2,3-dimethyl-2-butylamine derivatives.

ATP-sensitive potassium (K(ATP)) channels have important functions through their coupling of cellular energetic networks and their ability to decode metabolic signals, and they are implicated in diseases of many organs. K(ATP) channels are formed by the physical association between the inwardly rectifier potassium channels (Kir6.x) and the regulatory sulfonylurea receptor subunit (SUR), which form a hetero-octameric complex. Different subtypes of K(ATP) channels exist in various tissues. K(ATP) channel openers (KCOs) are classified into nine chemical families according to their molecular structures: (1) benzopyrans, (2) cyanoguanidines, (3) thioformamides, (4) pyrimidine derivatives, (5) pyridine derivatives, (6) benzothiadiazines, (7) dihydropyridines, (8) nicotinamide derivatives, and (9) aliphatic amines. Although the model also predicts that KCOs have four co-binding areas, it was hypothesized that the main contribution lies in the binding domain of hydrophobicity of the side chain. A series of compounds containing the skeleton of the aliphatic secondary amines as a side chain was designed. It was found that N-isopropyl 2,3-dimethyl-2-butylamine (iptakalim, 91) is a novel KCOs. Iptakalim regulates the pore selectively of the inwardly rectifier potassium channel and dilates smaller arteries, but has little effect on vasodilatation of the aorta. Iptakalim administered p.o. has selective and long-lasting antihypertensive effects in hypertensive animals and does not induce tolerance, but has little effect on blood pressure in normotensive animals. Meanwhile, it also reverses cardiovascular remodeling and protects the brain and kidney against damage caused by hypertension in animal models. Iptakalim is in phase II clinical trials now and has a promising future as a treatment for hypertension.

Treatment of daytime urinary incontinence in children: a systematic review of randomized controlled trials.

PURPOSE: We sought to determine the benefits and harms of interventions for children with daytime urinary incontinence. MATERIALS AND METHODS: Trials of any interventions for children with primary daytime incontinence (the urge syndrome and/or dysfunctional voiding) were identified from the Cochrane Controlled Trials Register, MEDLINE, EMBASE, reference lists of articles, abstracts from conference proceedings and contact with known experts in the field. Once identified, trial quality was assessed, data were extracted and results were expressed in terms of relative risks (RR) with 95% confidence intervals (CI) for individual trials, and summary estimates were obtained using a random effects model. All steps were done by 2 independent reviewers. RESULTS: Randomized trials of terodiline (2 studies), daytime alarms (1), imipramine (1) and biofeedback/oxybutynin (1) involving 383 children were reviewed. No intervention was demonstrated to be effective. In the latter trial, which was the only one to evaluate a currently used intervention, after 9 months of treatment there was no difference in the proportions of children with unimproved daytime wetting with oxybutynin (RR 0.74, CI 0.26 to 2.13) and biofeedback (0.92, 0.59 to 1.43) compared with placebo. CONCLUSIONS: No intervention tested in a trial to date has been proved to be of benefit to children with daytime urinary incontinence.

PD0084430: a non-nucleoside inhibitor of human cytomegalovirus replication in vitro.

Human cytomegalovirus (HCMV) is a major opportunistic pathogen in immunocompromised individuals. Current therapies target viral DNA replication and accumulate mutations that yield cross-resistance among the approved drugs. A novel, non-nucleoside inhibitor of HCMV replication, PD0084430, was identified in a screening assay using the HCMV beta-galactosidase recombinant RC256. The EC(50) for PD0084430 by inhibition of beta-galactosidase production is 1+/-0.7 microM. This antiviral activity was confirmed by yield reduction and plaque reduction assays using HCMV strain AD169. The TC(50) of PD0084430 as measured by (4C)thymidine incorporation is approximately 30 microM and by XTT is approximately 90 microM. The TC(50) for inhibition of cellular proliferation is approximately 20 microM. Time of addition experiments displayed a similar drop in efficacy for both PD0084430 and GCV when added after the onset of viral DNA replication. The transcomplementation assay for viral DNA replication, using a transfected ori(Lyt) containing plasmid, confirmed that viral DNA synthesis was inhibited at the same concentrations that showed antiviral activity. Western blots showed no apparent block of immediate early or early gene expression. Two ganciclovir (GCV) resistant isolates of HCMV tested showed no cross-resistance to PD0084430. These data suggested a potentially promising novel compound that inhibited HCMV at or before viral DNA replication. However, in vivo testing in mice dosed either orally or intraperitoneally showed rapid glucuronidation on the -OH group. SAR studies on this backbone showed that the -OH group was essential for the antiviral activity in vitro.

Benzonatate for opioid-resistant cough in advanced cancer.

Chronic cough is a distressing symptom experienced by approximately 37% of patients with advanced cancer. Palliation of chronic nonproductive cough should always first address the underlying cause but in some patients chronic, nonproductive cough persists and antitussive agents are required. Opioids are the gold standard cough suppressants, of which codeine is the most widely used; patients with an opioid-resistant cough often prove to be a therapeutic challenge. We report three patients with an opioid-resistant cough who achieved symptomatic relief with the peripherally acting nonopioid drug benzonatate.

Inhibitory effects of NS-21, a novel drug for urinary incontinence, and its active metabolite, RCC-36, on L-type calcium currents in isolated guinea pig detrusor smooth muscle cells.

The inhibitory effects of NS-21, a newly developed drug for the treatment of urinary frequency and urinary incontinence, and its active metabolite, RCC-36, on L-type Ca2+ currents (ICa) in guinea pig detrusor smooth muscle cells have been compared to those of terodiline by a whole-cell patch-clamp technique. Like terodiline (10 microM), both NS-21 (10 microM) and RCC-36 (10 microM) induced a sizeable decrease in ICa elicited from a holding potential of -60 mV without changing the current-voltage relationship. The three drugs shifted the inactivation curves for ICa in the hyperpolarizing direction by 13 to 20 mV but had no effect on the activation curves for ICa resulting in a decrease in the calcium window current. The inhibitory effects of NS-21 and RCC-36 were greater than those of terodiline. The three drugs inhibited ICa in a concentration- and holding-potential-dependent manner. The IC50 values at a holding potential of -60 mV were 7.9 microM for NS-21, 6.4 microM for RCC-36, and 5.9 microM for terodiline, and at -40 mV they were 1.3, 1.2, and 3.5 microM, respectively. The ratio calculated by dividing the IC50 value at -60 mV by the value at -40 mV was 6.1, 5.3 and 1.7, respectively, indicating that the inhibitory effects of NS-21 and RCC-36 on ICa were more sensitive to voltage than those of terodiline. These results suggest that NS-21 and RCC-36 could be more effective in the treatment of urinary bladder ailments, such as urinary frequency and urinary incontinence.

Concentration dependent cardiotoxicity of terodiline in patients treated for urinary incontinence.

OBJECTIVE: Terodiline, an antimuscarinic and calcium antagonist drug, was used to treat detrusor instability but was withdrawn in 1991 after provoking serious ventricular arrhythmias associated with increases in the corrected QT interval (QTc). This research was performed to relate drug induced electrocardiographic changes in asymptomatic recipients to plasma concentrations of the R(+) and S(-) terodiline enantiomers. SETTING: Urological and geriatric clinics and wards. SUBJECTS: Asymptomatic patients taking terodiline in stable dose. METHODS: Electrocardiograms (50 mm/s) were collected from patients while they were taking terodiline and compared with ECGs obtained before or after terodiline. QT interval, heart rate corrected QT interval (QTc), and QT dispersion (QTd) were measured. Drug induced electrocardiographic changes were related to plasma concentrations of R(+) and S(-) terodiline. RESULTS: During terodiline treatment mean QTc and QTd were prolonged (491(43) and 84 (35) ms 1/2) compared with measurements made off therapy (443 (33) and 42 (17) ms 1/2, paired t tests, P < 0.002 and P < 0.01 respectively) in the 12 patients in sinus rhythm. The mean (95% confidence interval) drug induced increases were 48 (23 to 74) ms 1/2 for QTc and 42 (13 to 70) ms 1/2 for QTd. These increases correlated with total plasma terodiline (QTc: r = 0.77, P < 0.006, QTd: r = 0.68, P < 0.025) and with plasma concentrations of both terodiline enantiomers. CONCLUSIONS: Terodiline increases QTc and QTd in a concentration dependent manner. It is not clear whether this is a stereoselective effect and, if so, which enantiomer is responsible. The results suggest that drug induced torsade de pointes is a type A (concentration dependent) adverse drug reaction.

Randomized double-blind trial of terodiline in the treatment of urge incontinence in women.

OBJECTIVE: To evaluate the effects of terodiline in women with urge incontinence. METHODS: After a 2-week run-in period, 93 women with urinary frequency and urge incontinence were randomized to either placebo or terodiline, 25 mg twice daily, in a double-blind study for 4 weeks. Symptoms were evaluated using daily frequency-volume charts to record voiding frequency, number of incontinent episodes, absorbent pad use, and quality of life. RESULTS: The terodiline group showed a 70% decrease in the mean (+/- standard deviation) number of incontinent episodes per week (15.8 +/- 24, decreasing to 4.9 +/- 11.9; P < .01), which persisted throughout the study period. The placebo group achieved a 9% reduction in the mean number of incontinent episodes (13.0 +/- 11.3, decreasing to 11.9 +/- 16; P < .05) only in the final week of treatment. Side effects, especially anticholinergic side effects, were more common in the terodiline group, but resulted in only one dropout. Both the treated and placebo groups improved in daytime frequency and quality-of-life indices. CONCLUSION: Terodiline is well tolerated and effective in reducing urge incontinent episodes in women.

Haloallylamine inhibitors of MAO and SSAO and their therapeutic potential.

Based on mechanistic understandings, molecular modeling and extensive quantitative structure-activity relationships, appropriately substituted haloallylamine derivatives were designed as potential mechanism-based inhibitors of MAO and/or SSAO. Potent inhibition of MAO-B and SSAO occurred with fluoroallylamines whereas chloroallylamines, such as MDL 72274A ((E)-2-phenyl-3-chloroallylamine hydrochloride), were selective and potent inhibitors of SSAO. MDL 72974A (E)-2-(4-fluorophenethyl)-3-fluoroallylamine hydrochloride is a potent (IC50 = 10(-9) M) inhibitor of both MAO-B and SSAO, with 190-fold lower affinity for MAO-A. In clinical studies, oral doses as low as 100 micrograms produced substantial inhibition of platelet MAO-B. Essentially complete inhibition occurred at 1 mg with the effect lasting 6-10 days. One or 4 mg MDL 72974A given daily for 28 days to 40 Parkinson's patients treated with L-dopa produced statistically significant reductions in the Unified Parkinson's Disease Rating Scale. MAO-B inhibitors, such as MDL 72974A and L-deprenyl, offer the potential of being neuroprotective in Parkinson's Disease and other neurogenerative disorders. Concommitant inhibition of SSAO may provide additional, but as yet unproven, advantages over pure inhibitors of MAO-B.

Effects of terodiline on urinary incontinence among older non-institutionalized women. Terodiline in the Elderly American Multicenter Study Group.

OBJECTIVE: To determine the effectiveness of terodiline, a drug with calcium antagonist and anticholinergic properties, on the frequency of incontinence in older non-institutionalized women. DESIGN: Randomized, placebo-controlled, parallel-group, double-blind trial. SETTING: Twelve outpatient clinics across the United States affiliated with programs in either geriatrics, gynecology, or urology. PARTICIPANTS: Ninety-eight women, age 60 or older, with symptoms of urge incontinence and self-reported frequency of incontinence four or more times per week and involuntary bladder contractions on dual-channel water cystometry. MAIN OUTCOME MEASURES: Self-reported urinary frequency, urgency, number of incontinence episodes, and number of heavily soaked pads. RESULTS: Eighty-one women, average age 71, completed the trial, 40 in the active drug group, 41 in the placebo group. Incontinence frequency and the number of heavily soaked pads were reduced in the active drug group by 64% and 55%, respectively, and by 21% (P = 0.002) and 9% (P = 0.04) in the placebo group. No patients dropped out due to adverse effects. An intention-to-treat analysis of all 98 patients yielded the same conclusion. CONCLUSION: Terodiline is highly effective in reducing incontinence in older, noninstitutionalized women with urge incontinence. Because of its potential association with polymorphic ventricular tachycardia (torsades de pointes), terodiline must undergo further testing to define its safety before it can be recommended for clinical use in the incontinent geriatric population.

MDL 72,974A: a selective MAO-B inhibitor with potential for treatment of Parkinson's disease.

MDL 72,974A [(E)-2-(4-fluorophenethyl)-3-fluoroallylamine, hydrochloride] was designed to be a selective, mechanism-based irreversible inhibitor of monoamine oxidase type B (MAO-B). The compound is a potent, selective MAO-B inhibitor in vitro and in vivo. In vitro studies revealed an IC50 value (MAO-B) of 3.6 nM with 189-fold selectivity compared to MAO-A. In rats, profound inhibition of MAO-B was achieved after a single oral dose with an ED50 of 0.18 mg/kg; a dose 44 times this amount was required to inhibit MAO-A by 50%. Selectivity was maintained following chronic dosing. MDL 72,974A had minimal sympathomimetic effects and did not potentiate the cardiovascular effects of tyramine, even at 50 times the MAO-B inhibiting dose. This inhibitor was equally effective and well-tolerated in man. In human volunteers, potent inhibition of platelet MAO-B activity was observed at submilligram doses (ED50 = 90 micrograms) following a single oral dose. Upon multiple oral doses of 100 micrograms, as much as 80% of MAO-B could be inhibited. In phase II studies, MDL 72,974A is proving to be a useful adjunct to conventional therapy. Patients (250) with Parkinson's disease, treated once daily with either 1 or 4 mg, together with L-Dopa and a decarboxylase inhibitor (MadoparR or SinemetR), saw significant improvements in symptoms compared with those on standard therapy without the inhibitor.

Urodynamic effects of intravesical instillation of terodiline in healthy volunteers and in patients with detrusor hyperactivity.

The effects of intravesical instillation of terodiline on urodynamic parameters were investigated in 8 healthy volunteers (10(-4) M.) and in 34 patients with detrusor hyperactivity (10(-5) M.) of neurogenic (22) or nonneurogenic (12) origin. The volunteers were investigated with conventional medium-fill cystometry, while in the patients a modified cystometric technique with slow intermittent filling was used. The reproducibility of the procedure was verified in 17 patients. Instillation of terodiline had no effect on the normal bladders nor were any improvements found in the nonneurogenic patients. In 12 patients in the neurogenic group treated with terodiline instillation the bladder capacity increased significantly (p < 0.05) from 289 +/- 32 to 413 +/- 55 ml. Within this group 5 patients were responders. It is suggested that pathophysiological changes may explain the difference between the neurogenic and nonneurogenic groups, and that the number of responders within the neurogenic group may be increased by an optimal drug preparation and increased dosage. Intravesical administration of terodiline may offer an alternative treatment in selected patients with detrusor hyperreflexia.