Given the failure to develop disease-modifying therapies for Alzheimer’s disease(AD),strategies aiming at preventing or delaying the onset of the disease are being prioritized.While the debate regarding whether depre...Given the failure to develop disease-modifying therapies for Alzheimer’s disease(AD),strategies aiming at preventing or delaying the onset of the disease are being prioritized.While the debate regarding whether depression is an etiological risk factor or a prodrome of AD rages on,a key determining factor may be the timing of depression onset in older adults.There is increasing evidence that untreated early-onset depression is a risk factor and that late-onset depression may be a catalyst of cognitive decline.Data from animal studies have shown a beneficial impact of selective serotonin reuptake inhibitors on pathophysiological biomarkers of AD including amyloid burden,tau deposits and neurogenesis.In humans,studies focusing on subjects with a prior history of depression also showed a delay in the onset of AD in those treated with most selective serotonin reuptake inhibitors.Paroxetine,which has strong anticholinergic properties,was associated with increased mortality and mixed effects on amyloid and tau deposits in mice,as well as increased odds of developing AD in humans.Although most of the data regarding selective serotonin reuptake inhibitors is promising,findings should be interpreted cautiously because of notable methodological heterogeneity between studies.There is thus a need to conduct large scale randomized controlled trials with long follow up periods to clarify the dose-effect relationship of specific serotonergic antidepressants on AD prevention.展开更多
AIM To investigate the relationship between selective serotonin reuptake inhibitor(SSRI)use and the subsequent development of irritable bowel syndrome(IBS).METHODS This retrospective,observational,population-based coh...AIM To investigate the relationship between selective serotonin reuptake inhibitor(SSRI)use and the subsequent development of irritable bowel syndrome(IBS).METHODS This retrospective,observational,population-based cohort study collected data from Taiwan’s National Health Insurance Research Database.A total of 19653patients newly using SSRIs and 78612 patients not using SSRIs,matched by age and sex at a ratio of 1:4, were enrolled in the study from January 1,2000 to December 31,2010.The patients were followed until IBS diagnosis,withdrawal from the National Health Insurance system,or the end of 2011.We analyzed the effects of SSRIs on the risk of subsequent IBS using Cox proportional hazards regression models.RESULTS A total of 236 patients in the SSRI cohort(incidence,2.17/1000 person-years)and 478 patients in the comparison cohort(incidence,1.04/1000 person-years)received a new diagnosis of IBS.The mean follow-up period from SSRI exposure to IBS diagnosis was 2.05years.The incidence of IBS increased with advancing age.Patients with anxiety disorders had a significantly increased adjusted hazard ratio(a HR)of IBS(a HR=1.33,95%CI:1.11-1.59,P=0.002).After adjusting for sex,age,urbanization,family income,area of residence,occupation,the use of anti-psychotics and other comorbidities,the overall a HR in the SSRI cohort compared with that in the comparison cohort was1.74(95%CI:1.44-2.10;P<0.001).The cumulative incidence of IBS was higher in the SSRI cohort than in the non-SSRI cohort(log-rank test,P<0.001).CONCLUSION SSRI users show an increased risk of subsequent diagnosis of IBS in Taiwan.展开更多
OBJECTIVE Selective serotonin reuptake inhibitors(SSRIs) bind 5-HT transporters,leading to the accumulation of 5-HT and amelioration of depression.Although different mouse strain showed different sensitivity to SSRIs ...OBJECTIVE Selective serotonin reuptake inhibitors(SSRIs) bind 5-HT transporters,leading to the accumulation of 5-HT and amelioration of depression.Although different mouse strain showed different sensitivity to SSRIs in mouse models of depression,the reason for these strain differences remains unclear.Here,therefore,in the present study,we examined immobility time and locomotor activity in two mouse strains,namely,C57BL/6 J and DBA/2 J mice,and the effects of the SSRIs fluoxetine.Furthermore,we analyzed 5-HT transporter binding and reuptake inhibition in both strains to explore their relationship with the immobility and locomotor activity effects of the three SSRIs in these two mouse strains.METHODS Strain differences in SSRI effects in the tail suspension test(TST) and forced swimming test(FST).To initiate our studies,we sought to confirm that SERT strain variation did not alter SERT protein expression,5-HT recognition,or uptake activity when expressed in C57BL/6 J and DBA/2 J mice.Radioligand binding assays were conducted to determine the affinity of the SSRIs for the 5-HT transporters in the two mouse strains.RESULTS SSRI citalopram dose-dependently reduced immobility time in both the FST and TST in DBA/2 J but not C57BL/6 J mouse strains,whereas fluoxetine showed opposite results.Paroxetine reduced immobility time similarly in both strains.The affinity of citalopram for the 5-HT transporter in DBA/2 J mice was 700-fold higher than that for in C57BL/6 J mice,whereas the affinity of fluoxetine in C57BL/6 J mice was 100-fold higher than that in the DBA/2 J mouse.Furthermore,High citalopram concentrations were required to [3 H]5-HT uptake in C57BL/6 J but not DBA/2 J mouse cortical synaptosomes,whereas fluoxetine also showed opposite results.CONCLUSION Immobility duration depends on 5-HT transporter binding levels,leading to apparent strain differences in immobility time in FST and TST.Furthermore,differences in 5-HT transporter binding may cause variations in SSRI responses on behaviors.SERT mutation mice maintained sensitivity to paroxetine,an antidepressant that is unaffected by the mouse mutation.Therefore,the background strain of these mice likely contributes to the acute behavioral actions of SSRIs in immobility time.These differences may help to explain some of the discrepancies in studies that used these strains of mice to examine the role of 5-HT in mouse models of depression.Future studies should investigate additional neural substrates and molecular mechanisms underlying strain variations in mouse models of depression to help identify genetic predispositions to this disorder in humans.展开更多
After spinal cord injury,the upward conduction of the spinal cord is lost,resulting in the loss of micturition control,which manifests as detrusor sphincter dyssynergia and insufficient micturition.Studies have shown ...After spinal cord injury,the upward conduction of the spinal cord is lost,resulting in the loss of micturition control,which manifests as detrusor sphincter dyssynergia and insufficient micturition.Studies have shown that serotonergic axons play important roles in the control of the descending urination tract.In this study,mouse models of moderate spinal cord contusions were established.The serotonin agonists quipazine(0.2 mg/kg),8-hydroxy-2-(di-n-propylamino)tetralin(8-OH-DAPT,0.1 mg/kg),buspirone(1 mg/kg),sumatriptan(1 mg/kg),and rizatriptan(50 mg/kg),the serotonin reuptake inhibitors fluoxetine(20 mg/kg)and duloxetine(1 mg/kg),and the dopamine receptor agonist SKF-82197(0.1 mg/kg)were intraperitoneally administered to the model mice 35 days post-injury in an acute manner.The voided stain on paper method and urodynamics revealed that fluoxetine reduced the amount of residual urine in the bladder and decreased bladder and external urethral sphincter pressure in a mouse model of moderate spinal cord injury.However,fluoxetine did not improve the micturition function in a mouse model of severe spinal cord injury.In contrast,the other serotonergic drugs had no effects on the micturition functions of spinal cord injury model mice.This study was ethically approved by the Institutional Animal Care and Use Committee of Jiangsu Province Hospital of Chinese Medicine(approval No.2020DW-20-02)on September 11,2020.展开更多
Serotonin syndrome(SS)is a drug-induced clinical syndrome resulting from increased serotonergic activity in the central nervous system.Although more than seven decades have passed since the first description of SS,it ...Serotonin syndrome(SS)is a drug-induced clinical syndrome resulting from increased serotonergic activity in the central nervous system.Although more than seven decades have passed since the first description of SS,it is still an enigma in terms of terminology,clinical features,etiology,pathophysiology,diagnostic criteria,and therapeutic measures.The majority of SS cases have previously been reported by toxicology or psychiatry centers,particularly in people with mental illness.However,serotonergic medications are used for a variety of conditions other than mental illness.Serotonergic properties have been discovered in several new drugs,including over-the-counter medications.These days,cases are reported in non-toxicology centers,such as perioperative settings,neurology clinics,cardiology settings,gynecology settings,and pediatric clinics.Overdoses or poisonings of serotonergic agents constituted the majority of the cases observed in toxicology or psychiatry centers.Overdose or poisoning of serotonergic drugs is uncommon in other clinical settings.Patients may develop SS at therapeutic dosages.Moreover,these patients may continue to use serotonergic medications even if they develop mild to moderate SS due to several reasons.Thus,the clinical presentation(onset,severity,and clinical features)in such instances may not exactly match what toxicologists or psychiatrists observe in their respective settings.They produce considerable diversity in many aspects of SS.However,other experts discount these new developments in SS.Since SS is a potentially lethal illness,consensus is required on several concerns related to SS.展开更多
We evaluated the genotypes of the serotonin transporter gene （5-HTT） in patients with premature ejaculation （PE） to determine the role of genetic factors in the etiopathogenesis of PE and possibly to identify the ...We evaluated the genotypes of the serotonin transporter gene （5-HTT） in patients with premature ejaculation （PE） to determine the role of genetic factors in the etiopathogenesis of PE and possibly to identify the patient subgroups. A total of 70 PE patients and 70 controls were included in this study. All men were heterosexual, had no other disorders and were either married or in a stable relationship. PE was defined as ejaculation that occurred within 1 min of vaginal intromission. Genomic DNA from patients and controls was analyzed using polymerase chain reaction, and allelic variations of the promoter region of the serotonin transporter gene （5-HTTLPR） were determined. The 5-HTTLPR （serotonin transporter promoter gene） genotypes in PE patients vs. controls were distributed as follows： L/L 16% vs. 17%, L/S 30% vs. 53% and S/S 54% vs. 28%. We examined the haplotype analysis for three polymorphisms of the 5-HTTLPR gene： LL, LS and SS. The appropriateness of the allele frequencies in the 5-HTTLPR gene was analyzed by the Hardy-Weinberg equilibrium using the Z-test. The short （S） allele of the 5-HTTLPR gene was significantly more frequent in PE patients than in controls （P 〈 0.05）. We suggest that the 5-HTTLPR gene plays a role in the pathophysiology of all primary PE cases. Further studies are needed to evaluate the relationship between 5-HTTLPR gene polymorphism and patient subgroup （such as primary and secondary PE） responses to selective serotonin reuptake inhibitors as well as ethnic differences.展开更多
文摘Given the failure to develop disease-modifying therapies for Alzheimer’s disease(AD),strategies aiming at preventing or delaying the onset of the disease are being prioritized.While the debate regarding whether depression is an etiological risk factor or a prodrome of AD rages on,a key determining factor may be the timing of depression onset in older adults.There is increasing evidence that untreated early-onset depression is a risk factor and that late-onset depression may be a catalyst of cognitive decline.Data from animal studies have shown a beneficial impact of selective serotonin reuptake inhibitors on pathophysiological biomarkers of AD including amyloid burden,tau deposits and neurogenesis.In humans,studies focusing on subjects with a prior history of depression also showed a delay in the onset of AD in those treated with most selective serotonin reuptake inhibitors.Paroxetine,which has strong anticholinergic properties,was associated with increased mortality and mixed effects on amyloid and tau deposits in mice,as well as increased odds of developing AD in humans.Although most of the data regarding selective serotonin reuptake inhibitors is promising,findings should be interpreted cautiously because of notable methodological heterogeneity between studies.There is thus a need to conduct large scale randomized controlled trials with long follow up periods to clarify the dose-effect relationship of specific serotonergic antidepressants on AD prevention.
文摘AIM To investigate the relationship between selective serotonin reuptake inhibitor(SSRI)use and the subsequent development of irritable bowel syndrome(IBS).METHODS This retrospective,observational,population-based cohort study collected data from Taiwan’s National Health Insurance Research Database.A total of 19653patients newly using SSRIs and 78612 patients not using SSRIs,matched by age and sex at a ratio of 1:4, were enrolled in the study from January 1,2000 to December 31,2010.The patients were followed until IBS diagnosis,withdrawal from the National Health Insurance system,or the end of 2011.We analyzed the effects of SSRIs on the risk of subsequent IBS using Cox proportional hazards regression models.RESULTS A total of 236 patients in the SSRI cohort(incidence,2.17/1000 person-years)and 478 patients in the comparison cohort(incidence,1.04/1000 person-years)received a new diagnosis of IBS.The mean follow-up period from SSRI exposure to IBS diagnosis was 2.05years.The incidence of IBS increased with advancing age.Patients with anxiety disorders had a significantly increased adjusted hazard ratio(a HR)of IBS(a HR=1.33,95%CI:1.11-1.59,P=0.002).After adjusting for sex,age,urbanization,family income,area of residence,occupation,the use of anti-psychotics and other comorbidities,the overall a HR in the SSRI cohort compared with that in the comparison cohort was1.74(95%CI:1.44-2.10;P<0.001).The cumulative incidence of IBS was higher in the SSRI cohort than in the non-SSRI cohort(log-rank test,P<0.001).CONCLUSION SSRI users show an increased risk of subsequent diagnosis of IBS in Taiwan.
文摘OBJECTIVE Selective serotonin reuptake inhibitors(SSRIs) bind 5-HT transporters,leading to the accumulation of 5-HT and amelioration of depression.Although different mouse strain showed different sensitivity to SSRIs in mouse models of depression,the reason for these strain differences remains unclear.Here,therefore,in the present study,we examined immobility time and locomotor activity in two mouse strains,namely,C57BL/6 J and DBA/2 J mice,and the effects of the SSRIs fluoxetine.Furthermore,we analyzed 5-HT transporter binding and reuptake inhibition in both strains to explore their relationship with the immobility and locomotor activity effects of the three SSRIs in these two mouse strains.METHODS Strain differences in SSRI effects in the tail suspension test(TST) and forced swimming test(FST).To initiate our studies,we sought to confirm that SERT strain variation did not alter SERT protein expression,5-HT recognition,or uptake activity when expressed in C57BL/6 J and DBA/2 J mice.Radioligand binding assays were conducted to determine the affinity of the SSRIs for the 5-HT transporters in the two mouse strains.RESULTS SSRI citalopram dose-dependently reduced immobility time in both the FST and TST in DBA/2 J but not C57BL/6 J mouse strains,whereas fluoxetine showed opposite results.Paroxetine reduced immobility time similarly in both strains.The affinity of citalopram for the 5-HT transporter in DBA/2 J mice was 700-fold higher than that for in C57BL/6 J mice,whereas the affinity of fluoxetine in C57BL/6 J mice was 100-fold higher than that in the DBA/2 J mouse.Furthermore,High citalopram concentrations were required to [3 H]5-HT uptake in C57BL/6 J but not DBA/2 J mouse cortical synaptosomes,whereas fluoxetine also showed opposite results.CONCLUSION Immobility duration depends on 5-HT transporter binding levels,leading to apparent strain differences in immobility time in FST and TST.Furthermore,differences in 5-HT transporter binding may cause variations in SSRI responses on behaviors.SERT mutation mice maintained sensitivity to paroxetine,an antidepressant that is unaffected by the mouse mutation.Therefore,the background strain of these mice likely contributes to the acute behavioral actions of SSRIs in immobility time.These differences may help to explain some of the discrepancies in studies that used these strains of mice to examine the role of 5-HT in mouse models of depression.Future studies should investigate additional neural substrates and molecular mechanisms underlying strain variations in mouse models of depression to help identify genetic predispositions to this disorder in humans.
基金This work was supported by Jiangsu Province Hospital of Chinese Medicine,No.Y19061(to LM).
文摘After spinal cord injury,the upward conduction of the spinal cord is lost,resulting in the loss of micturition control,which manifests as detrusor sphincter dyssynergia and insufficient micturition.Studies have shown that serotonergic axons play important roles in the control of the descending urination tract.In this study,mouse models of moderate spinal cord contusions were established.The serotonin agonists quipazine(0.2 mg/kg),8-hydroxy-2-(di-n-propylamino)tetralin(8-OH-DAPT,0.1 mg/kg),buspirone(1 mg/kg),sumatriptan(1 mg/kg),and rizatriptan(50 mg/kg),the serotonin reuptake inhibitors fluoxetine(20 mg/kg)and duloxetine(1 mg/kg),and the dopamine receptor agonist SKF-82197(0.1 mg/kg)were intraperitoneally administered to the model mice 35 days post-injury in an acute manner.The voided stain on paper method and urodynamics revealed that fluoxetine reduced the amount of residual urine in the bladder and decreased bladder and external urethral sphincter pressure in a mouse model of moderate spinal cord injury.However,fluoxetine did not improve the micturition function in a mouse model of severe spinal cord injury.In contrast,the other serotonergic drugs had no effects on the micturition functions of spinal cord injury model mice.This study was ethically approved by the Institutional Animal Care and Use Committee of Jiangsu Province Hospital of Chinese Medicine(approval No.2020DW-20-02)on September 11,2020.
文摘Serotonin syndrome(SS)is a drug-induced clinical syndrome resulting from increased serotonergic activity in the central nervous system.Although more than seven decades have passed since the first description of SS,it is still an enigma in terms of terminology,clinical features,etiology,pathophysiology,diagnostic criteria,and therapeutic measures.The majority of SS cases have previously been reported by toxicology or psychiatry centers,particularly in people with mental illness.However,serotonergic medications are used for a variety of conditions other than mental illness.Serotonergic properties have been discovered in several new drugs,including over-the-counter medications.These days,cases are reported in non-toxicology centers,such as perioperative settings,neurology clinics,cardiology settings,gynecology settings,and pediatric clinics.Overdoses or poisonings of serotonergic agents constituted the majority of the cases observed in toxicology or psychiatry centers.Overdose or poisoning of serotonergic drugs is uncommon in other clinical settings.Patients may develop SS at therapeutic dosages.Moreover,these patients may continue to use serotonergic medications even if they develop mild to moderate SS due to several reasons.Thus,the clinical presentation(onset,severity,and clinical features)in such instances may not exactly match what toxicologists or psychiatrists observe in their respective settings.They produce considerable diversity in many aspects of SS.However,other experts discount these new developments in SS.Since SS is a potentially lethal illness,consensus is required on several concerns related to SS.
文摘We evaluated the genotypes of the serotonin transporter gene （5-HTT） in patients with premature ejaculation （PE） to determine the role of genetic factors in the etiopathogenesis of PE and possibly to identify the patient subgroups. A total of 70 PE patients and 70 controls were included in this study. All men were heterosexual, had no other disorders and were either married or in a stable relationship. PE was defined as ejaculation that occurred within 1 min of vaginal intromission. Genomic DNA from patients and controls was analyzed using polymerase chain reaction, and allelic variations of the promoter region of the serotonin transporter gene （5-HTTLPR） were determined. The 5-HTTLPR （serotonin transporter promoter gene） genotypes in PE patients vs. controls were distributed as follows： L/L 16% vs. 17%, L/S 30% vs. 53% and S/S 54% vs. 28%. We examined the haplotype analysis for three polymorphisms of the 5-HTTLPR gene： LL, LS and SS. The appropriateness of the allele frequencies in the 5-HTTLPR gene was analyzed by the Hardy-Weinberg equilibrium using the Z-test. The short （S） allele of the 5-HTTLPR gene was significantly more frequent in PE patients than in controls （P 〈 0.05）. We suggest that the 5-HTTLPR gene plays a role in the pathophysiology of all primary PE cases. Further studies are needed to evaluate the relationship between 5-HTTLPR gene polymorphism and patient subgroup （such as primary and secondary PE） responses to selective serotonin reuptake inhibitors as well as ethnic differences.
