Augmentation therapy with tandospirone citrate in vascular depression patients with mild cognitive impairment: A prospective randomized clinical trial

Cognitive impairment is a prominent clinical manifestation of vascular depression (VaDep). The current study aimed to assess the efficacy of tandospirone citrate in VaDep cases with mild cognitive impairment (VaDep-MCI) as well as the role of plasma monoamine neurotransmitters during the treatment. In this single-blind, randomized controlled study, 116 participants were randomly assigned to the tandospirone (tandospirone citrate-escitalopram) and control (escitalopram) groups. The primary endpoints were changes in cognitive test scores from baseline to Week 8, including the Rey Auditory Verbal Learning Test (RAVLT), Semantic Verbal Fluency (SVF) test, Trail Making Test (TMT), Digital Span Test (DST) and Clock Drawing Test (CDT) scores. Generalized estimating equation models were used to examine repeated measures. The results showed that compared with the changes in the control group from baseline to Week 8, the tandospirone group showed more significant changes in SVF score at Weeks 4 (p < 0.05) and 8 (p < 0.001), and TMT (B-A) score at Week 8 (p < 0.05). RAVLT, DST and DCT scores were relatively stable in both groups during the study period. Moreover, mediation analysis showed that these results were not mediated by the alleviation of depression symptoms. Partial Spearman correlation analysis showed that only plasma 5-hydroxytryptamine (5-HT) was positively correlated with Hamilton Depression Rating Scale score after Bonferroni correction (r = 0.347, p < 0.001). Augmentation therapy with tandospirone citrate improved the executive and language functions of VaDep-MCI patients. Additionally, plasma 5-HT levels may serve as a potential biomarker of VaDep severity. These findings may provide clinical insights into the treatment of vascular depression.

Early outcomes, associated factors and predictive values of clinical outcomes of tandospirone in generalized anxiety disorder: a post-hoc analysis of a randomized, controlled, multicenter clinical trial

OBJECTIVE

To examine the early outcomes, associated factors and predictive values of clinical outcomes of different tandospirone doses in patients with a generalized anxiety disorder (GAD).

METHODS

This was a posthoc analysis of "a randomized, controlled multicenter clinical trial of the efficacy and safety of different doses of tandospirone on GAD". A total of 274 patients with GAD were included and randomized into the high-dose (tandospirone 60 mg/d) and low-dose (tandospirone 30 mg/d) groups for a 6-week treatment. The Hamilton Anxiety (HAMA), Clinical Global Impression-Severity (CGI-S), Short-Form-12 (SF-12) scales were used for assessment. The trial was registered at clinical trail.gov (NCT01614041).

RESULTS

(1) In the first week of treatment, 35.8% of patients in the high-dose group fulfilled the early onset criteria, which was significantly higher than 19.0% found in the low-dose group (p = 0.002). In the second week of treatment, 22.6% of patients in the high-dose group achieved an early response, versus 12.4% in the low-dose group, indicating a significant difference (p = .026). (2) Factors associated with early onset at week 1 included baseline HAMA total score (OR = 0.916, 95%CI 0.882-0.952), age (OR = 0.974, 95%CI 0.950-0.998), drug dose (30 mg vs. 60 mg; OR = 0.298, 95%CI 0.156-0.568) and SF-12 physiological total score (OR = 1.030, 95%CI 1.010-1.050). (3) Early onset was significantly associated with response rate (OR = 18.34, 95%CI 12.10-27.81), remarkable response rate (OR = 27.56, 95%CI 11.65-65.17) and recovery rate (OR = 11.85, 95%CI 4.98-28.18). Group (high dose group vs. low dose group) (χ² = 8.535, p = .003) and baseline HAMA total score (χ² = 70.840, p < .001) were independent predictors of onset time.

CONCLUSIONS

The early outcomes of high-dose tandospirone in the treatment of GAD are better than those of the low-dose group. Patients with younger age at onset, milder anxiety symptoms and better physiological functions administered high-dose tandospirone showed rapid onset, great early outcomes, high recovery rate and good prognosis. Drug onset time had a good predictive effect on treatment outcome.

Clinical Efficacy of Tandospirone on Functional Dyspepsia Patients with Anxiety: A Randomized, Placebo-Controlled Study

BACKGROUND

Functional dyspepsia (FD) is characterized with multiple symptoms of indigestion and often accompanied with anxiety. However, there is currently an absence of effective treatment. Tandospirone is commonly used to treat generalized anxiety disorders. Whether tandospirone can improve the clinical symptoms of FD remain unknown.

AIMS

The present study was designed to explore the pharmacological effect of tandospirone on FD patient with anxiety, and the potential mechanisms were also elucidated.

METHODS

FD patients with anxiety were randomly divided into placebo and tandospirone treatment groups. Healthy volunteers were simultaneously recruited as control group. The gastrointestinal symptom score (GIS) and Hamilton anxiety scale (HAM-A) were performed before and after treatments with placebo or tandospirone. The serum levels of brain-derived neurotrophic factor (BDNF) and multiple inflammatory cytokines including tumor necrosis factor-α (TNF-α), and interleukin (IL)-6, IL-4, IL-1β, and IL-10 were determined. Regression analyses relating BDNF levels and gastrointestinal symptoms were performed.

RESULTS

Tandospirone significantly alleviated the gastrointestinal and anxiety symptoms of FD patient, as evidenced by reductions of GIS index and HAM-A scores. Compared with the healthy volunteers, FD patients had lower BDNF and IL-10 levels, but higher levels of IL-6 and TNF-α. Importantly, tandospirone increased serum BDNF and IL-10 and decreased IL-6 levels in FD patients. Relative analysis revealed that BDNF level was negatively associated with gastrointestinal symptoms in FD patients.

CONCLUSION

Tandospirone effectively improved both anxiety and gastrointestinal symptoms of patients with FD, and these therapeutic effects may be associated with the modulation of BDNF and inflammatory cytokines.

Pre-treatment with Tandospirone attenuates fentanyl-induced respiratory depression without affecting the analgesic effects of fentanyl in rodents

Opioid analgesics are widely used to treat acute, postoperative, and chronic pain. However, opioid receptor activation can result in severe respiratory depression. In this study, we demonstrated that Tandospirone (TS), a selective serotonin-1A receptor partial agonist, is effective against opioid-induced respiratory depression. Fentanyl was used to establish a respiratory depression model in rodents. We observed the effects of TS on respiratory depression in rats by using plethysmographic recordings and arterial oxygen saturation. In addition, we evaluated the effects of TS on fentanyl-induced sedation and analgesia by using the loss of righting reflex (LORR) and hot-plate tests, respectively. Rats (n = 5) were treated with TS or saline 5 min prior to fentanyl administration. TS [2 mg/kg, intravenous (i.v.)] dose-dependently attenuated fentanyl-induced respiratory depression versus saline + fentanyl group. Furthermore, pre-treatment with TS (2 mg/kg, i.v.) increased arterial oxygen saturation to 76.5 ± 2.0% at 5 min after fentanyl injection, compared with 35.9 ± 2.5% in saline pre-treated rats (P < 0.001), whereas the time to induction of LORR (P > 0.99) and duration of LORR (P = 0.95) did not differ between the "TS + fentanyl" and "saline + fentanyl" group. The antinociceptive effect of fentanyl was not affected by the administration of TS (P = 0.99) in mice (n = 10). In conclusion, we found that TS, a novel non-benzodiazepine anxiolytic/antidepressant drug, could attenuate severe fentanyl-induced respiratory depression and did not affect the analgesic/sedative effect of fentanyl. The clinical application of TS could significantly improve pain management.

5-HT1A Partial Agonist Tandospirone for Behavioral and Psychological Symptoms in Oldest-old Patients with Dementia at a Special Elderly Nursing Home

OBJECTIVE

To investigate the efficacy of tandospirone, an azapirone anxiolytic similar to buspirone that is used in Japan, for behavioral and psychological symptoms of dementia (BPSD), especially in oldest-old patients.

METHODS

This was an open-label observational study involving residents with BPSD in a special elderly nursing home between August 2013 and August 2018. The severity of dementia was assessed using the Clinical Dementia Rating (CDR) scale; as the main outcomes, the severity of BPSD was assessed using the Clinical Global Impressions-Severity scale (CGI-S) and Neuropsychiatric Inventory-12 (NPI-12) at baseline and 4 weeks after the maintenance dose of tandospirone was reached. The administration of tandospirone started at 30 mg, divided into three doses per day. Two weeks later, if the efficacy was sufficient based on the clinical nursing record, that dose was continued; if the efficacy was insufficient, the daily dose was increased from 40 mg/day to a maximum dose of 60 mg/day.

RESULTS

Thirty-three participants (25 females [76%], mean age 87.1 ± 5.4 years) completed the study. Twenty-three participants (70%) were oldest-old (18 females [78%], mean age 89.9 ± 3.4 years). The mean CDR score was 2.9 ± 0.3 in all participants. Tandospirone treatment showed few or no obvious adverse effects and significantly improved CGI-S scores, as well as total scores and many subscale scores on the NPI-12, in both the sample at large and the oldest-old participants.

CONCLUSION

This study demonstrated the efficacy and safety of tandospirone for BPSD in oldest-old participants.

Vasorelaxant effects of benzodiazepines, non-benzodiazepine sedative-hypnotics, and tandospirone on isolated rat arteries

Benzodiazepines (BDZs) and non-BDZ sedative-hypnotics are effective for the management of chronic insomnia; however, they are associated with adverse effects such as headache, dizziness, and palpitations. Furthermore, long-term use of these medications is associated with decreased blood pressure (BP) or depressed baroreflex function. Therefore, here, we assessed whether BDZs and non-BDZs cause vasorelaxation directly. Vasorelaxation in response to 22 BDZs, 2 non-BDZs, and tandospirone was determined by myograph methods using isolated Wistar rat thoracic aortas. All the drugs relaxed phenylephrine-contracted rat aortas in a concentration-dependent manner. Zolpidem and tandospirone caused over 80% relaxation at a concentration of 10 μM; diazepam, estazolam, etizolam, and tofisopam caused 60-70% relaxation; whereas 18 other BDZs (alprazolam, bromazepam, brotizolam, chlordiazepoxide, clobazam, clonazepam, clorazepate, ethyl loflazepate, flunitrazepam, flurazepam, lorazepam, lormetazepam, midazolam, nimetazepam, nitrazepam, oxazepam, temazepam, and triazolam) and zaleplon caused less than 50% relaxation. The relaxation was partially but significantly inhibited to the same extent by a nitric oxide (NO) synthase antagonist and after endothelium removal. Binding assay of gamma-aminobutyric acid type A receptors was performed using [3H]flunitrazepam. No correlation was observed between vasorelaxation at a concentration of 10 μM and the binding affinities for 23 drugs. The study demonstrated that zaleplon, zolpidem, tandospirone, and many BDZs cause vasorelaxation to different extents via endothelial NO-dependent and endothelium-independent pathways. In conclusion, the direct vasodilatory effects of these drugs may be involved in the mechanisms underlying their adverse effects. Additionally, the decreased BP observed in persons who take BDZs or non-BDZs may be partly due to direct vasodilation.

Tandospirone enhances the anti-myocardial fibrosis effect of valsartan in spontaneously hypertensive rats

PURPOSE

Myocardial fibrosis (MF) is an unavoidable complication in patients with hypertensive heart disease. Valsartan, a widely used antihypertensive drug, was reported to inhibit MF. Deficiency in the 5-hydroxytryptamine (5-HT, serotonin) transporter gene has been proven to cause MF. Long-term sympathetic nerve excitability activates renin angiotensin aldosterone system leading to MF. Tandospirone, a partial agonist of the 5-HT1A receptor, has been commonly used to relieve psychiatric symptoms. However, there is limited evidence on the combination of valsartan and tandospirone for the treatment of MF. Therefore, we investigated the synergistic effect of tandospirone on the anti-MF activity of valsartan in spontaneously hypertensive rats (SHRs).

METHODS

Systolic blood pressure (SBP) of SHRs (12-week-old) was measured weekly using the tail-cuff method for eight weeks; the left ventricular was collected and weighted for calculation of the left ventricular mass index (LVMI). The myocardial histopathology of left ventricle was evaluated in rats by hematoxylin and eosin (H&E) and Mason's trichrome staining assays. The mRNA and protein expressions of transforming growth factor β (TGF-β1), Sma- and Mad-related protein 3 (Smad3), and fibronectin (Fn) were investigated by real time PCR, immunohistochemistry, and Western blotting analysis, respectively.

RESULTS

Tandospirone (40 mg/kg) could significantly improve the effect of valsartan (30 mg/kg) in decreasing the SBP of SHRs and lower the ratio of the LVMI in SHRs, compared to that of rats treated with valsartan or tandospirone alone. Tandospirone could also enhance the valsartan-induced reduction in collagen deposition in the myocardial tissues of SHRs. Furthermore, tandospirone could enhance the effect of valsartan on downregulating the expression levels of TGF-β1, Smad3, and Fn at both mRNA and protein levels.

CONCLUSION

We report for the first time that tandospirone could improve the anti-MF efficacy of valsartan via the TGF-β1/Smad3 signaling pathway in SHRs. Our findings may provide valuable insight into the scientific rationale for combining tandospirone and valsartan in the treatment of MF clinically.

Simultaneous determination of tandospirone and its active metabolite, 1-[2-pyrimidyl]-piperazine in rat plasma by LC-MS/MS and its application to a pharmacokinetic study

A rapid, sensitive and selective liquid chromatography-tandem mass spectrometry method for the detection of tandospirone (TDS) and its active metabolite 1-[2-pyrimidyl]-piperazine (1-PP) in Sprague-Dawley rat plasma is described. It was employed in a pharmacokinetic study. These analytes and the internal standards were extracted from plasma using protein precipitation with acetonitrile, then separated on a CAPCELL PAK ADME C₁₈ column using a mobile phase of acetonitrile and 5 mm ammonium formate acidified with formic acid (0.1%, v/v) at a total flow rate of 0.4 mL/min. The detection was performed with a tandem mass spectrometer equipped with an electrospray ionization source. The method was validated to quantify the concentration ranges of 1.000-500.0 ng/mL for TDS and 10.00-500.0 ng/mL for 1-PP. Total time for each chromatograph was 3.0 min. The intra-day precision was between 1.42 and 6.69% and the accuracy ranged from 95.74 to 110.18% for all analytes. Inter-day precision and accuracy ranged from 2.47 to 6.02% and from 98.37 to 105.62%, respectively. The lower limits of quantification were 1.000 ng/mL for TDS and 10.00 ng/mL for 1-PP. This method provided a fast, sensitive and selective analytical tool for quantification of tandospirone and its metabolite 1-PP in plasma necessary for the pharmacokinetic investigation.

A controlled study of the efficacy and safety of tandospirone citrate combined with escitalopram in the treatment of vascular depression: A pilot randomized controlled trial at a single-center in China

Vascular depression can respond poorly to antidepressants. This study aimed to explore the efficacy and safety of tandospirone plus escitalopram for treating vascular depression with anxiety. This pilot randomized controlled trial included consecutive inpatients/outpatients with vascular depression/anxiety at the Department of Neurology, Fujian Medical University Union Hospital, China (January 2014 to December 2016). Among 157 patients screened, 100 were randomly divided into the tandospirone + escitalopram (combination therapy) and escitalopram (monotherapy) groups equally, and then followed for 8 weeks. Efficacy was evaluated using the Hamilton Depression (HAMD), Hamilton Anxiety (HAMA), Clinical Global Impression (CGI) and Mini-Mental State examination (MMSE) scales. Adverse events (AEs) were assessed with the Treatment Emergent Symptom Scale (TESS). HAMD and HAMA scores decreased progressively, showing reductions versus baseline at 1, 2, 4 and 8 weeks in both groups (P < 0.001). HAMD and HAMA scores were lower in the tandospirone + escitalopram group than those in the escitalopram group at 1 and 2 weeks (P < 0.001), but not at 4 and 8 weeks. Improvements in CGI scores (severity, improvement and efficacy indexes) were greater in the tandospirone + escitalopram group than that in the escitalopram group at 1 and 2 weeks (P < 0.01), but not at 4 and 8 weeks. The tandospirone + escitalopram group had higher MMSE scores than that in the escitalopram group at 4 and 8 weeks (P < 0.01). All AEs were mild, and the rates were comparable between groups. Augmentation of escitalopram with tandospirone accelerates the onset of anti-depressive and anxiolytic effects and improves cognitive function in patients with vascular depression and anxiety.

Neurosteroid pregnenolone sulfate, alone, and as augmentation of lurasidone or tandospirone, rescues phencyclidine-induced deficits in cognitive function and social interaction

BACKGROUND

Pregnenolone sulfate (PregS), an endogenous neurosteroid, which negatively and positively modulates gamma amino butyric acid subunit A (GABA_A) and N-methyl D-aspartate (NMDA) receptors (R) respectively, among other potential neuroplastic changes on synaptic processes, has shown some beneficial effects on treating cognitive impairment associated with schizophrenia (CIAS) and negative symptoms. Lurasidone (Lur), an atypical antipsychotic drug (AAPD), and tandospirone (Tan), a 5-HT_1A R partial agonist, have also been reported to improve cognitive or negative symptoms, or both, in some schizophrenia patients.

METHODS

We tested whether PregS, by itself, and in combination with Lur or Tan could rescue persistent deficits produced by subchronic treatment with the NMDAR antagonist, phencyclidine (PCP)-in episodic memory, executive functioning, and social behavior, using novel object recognition (NOR), operant reversal learning (ORL), and social interaction (SI) tasks, in male C57BL/6 J mice.

RESULTS

PregS (10, but not 3 mg/kg) significantly rescued subchronic PCP-induced NOR and SI deficits. Co-administration of sub-effective doses (SEDs) of PregS (3 mg/kg) + Lur (0.1 mg/kg) or Tan (0.03 mg/kg) rescued scPCP-induced NOR and SI deficits. Further, PregS (30, but not 10 mg/kg) rescued PCP-induced ORL deficit, as did the combination of SED PregS (10 mg/kg) +SED Lur (1 mg/kg) or Tan (1 mg/kg).

CONCLUSION

PregS was effective alone and as adjunctive treatment for treating two types of cognitive impairments and negative symptoms in this schizophrenia model. Further study of the mechanisms by which PregS alone and in combination with AAPDs and 5-HT_1A R partial agonists, rescues the deficits in cognition and SI in this preclinical model is indicated.

Effects of tandospirone augmentation in major depressive disorder patients with high anxiety: A multicenter, randomized, parallel-controlled, open-label study

BACKGROUND

High levels of anxiety symptoms are common in individuals with major depressive disorder (MDD). Adjunctive anxiolytics are widely used in such patients; however, only a few studies have examined the strategy using tandospirone. This study aimed to evaluate the efficacy and safety of adjunctive tandospirone in individuals with MDD and high level of anxiety symptoms.

METHODS

A multicenter, randomized, parallel-controlled, open-label study was conducted to evaluate the efficacy and safety of tandospirone coupled with selective serotonin reuptake inhibitors (SSRIs) in patients with MDD and high level of anxiety symptoms. Two hundred and forty-five patients fulfilling the DSM-IV-TR criteria for MDD were randomly assigned to 6 weeks of either SSRIs and tandospirone or SSRIs alone treatment. The efficacy was measured by HAMA total scores, HAMD-17 total scores, and Clinical Global Impressions severity subscale (CGI-S) score.

RESULTS

After a 6-week follow-up, two hundred and thirty patients completed this study. Tandospirone coupled with SSRIs significantly improved depressive and anxiety symptoms compared to monotherapy with SSRIs as assessed by HAMD-17 total score (P = 0.003), HAMA total score (P = 0.010), and CGI-S score at week 6 (P = 0.003). The incidence rate of treatment-emergent adverse events (TEAEs) was similar in both groups; the therapy was well-tolerated.

CONCLUSIONS

Short-term tandospirone augmentation was effective and well-tolerated in this study. Addition of tandospirone may improve outcomes in MDD patients with high anxiety.

Adjunctive azapirone for schizophrenia: A meta-analysis of randomized, double-blind, placebo-controlled trials

Azapirones, which are serotonin_1A (5-HT_1A) receptor partial agonists, have been used as an adjunctive treatment for schizophrenia with mixed results. This is a meta-analysis of the efficacy and tolerability of azapirones for schizophrenia based on randomized, double-blind, placebo-controlled trials (RCTs). English and Chinese databases were systematically and independently searched by two investigators. Data were extracted and analyzed using the RevMan software (version 5.3). Seven RCTs (n = 368) of azapirones (buspirone in 6 RCTs and tandospirone in 1 RCT) were identified and analyzed. Only adjunctive buspirone outperformed placebo regarding total psychopathology [standardized mean difference: -1.03 (95% confidence interval (CI): -1.91, -0.15), P = 0.02; I² = 92%], but the significance disappeared in sensitivity analysis after removing two outlying studies, and in 10 of the 12 subgroup analyses. In 5 RCTs examining neurocognitive function of azapirones, only 2 RCTs found the superiority of buspirone in improving attention/speeded motor performance, verbal and performance intelligence. Adjunctive buspirone outperformed placebo regarding extrapyramidal symptoms [SMD:-0.51, (95%CI: -0.99, -0.02), P = 0.04; I² = 0%]. Similar rates of discontinuation [risk ratio:1.06 (95%CI:0.54, 2.07), P = 0.86, I² = 0%] and adverse drug reactions were found between both groups. Adjunctive buspirone and tandospirone failed to show efficacy for psychotic symptoms, but adjunctive buspirone may be associated with improvement in extrapyramidal symptoms and cognitive deficits in schizophrenia. Due to the preliminary nature of this meta-analysis, larger sample size and higher quality RCTs are needed to confirm these finding.

5-HT1A receptor agonists, xaliproden and tandospirone, inhibit the increase in the number of cutaneous mast cells involved in the exacerbation of mechanical allodynia in oxaliplatin-treated mice

Oxaliplatin causes peripheral neuropathy as a major dose-limiting side effect, and the control of this neuropathy is difficult. This study was designed to investigate whether prophylactic repetitive administration of 5-HT1A receptor agonists inhibits oxaliplatin-induced mechanical allodynia in mice. Repetitive administration of 5-HT1A receptor agonists (xaliproden and tandospirone) inhibited mechanical allodynia induced by a single intraperitoneal injection of oxaliplatin. These agonists also inhibited oxaliplatin-induced mast cell migration, which is involved in the induction of mechanical allodynia. These results suggest that the prophylactic repetitive administration of 5-HT1A receptor agonists attenuates oxaliplatin-induced mechanical allodynia by inhibiting the cutaneous mast cell migration.

Serotonin (5-HT)1A receptor agonism and 5-HT7 receptor antagonism ameliorate the subchronic phencyclidine-induced deficit in executive functioning in mice

RATIONALE

Reversal learning (RL), a type of executive function, dependent on prefrontal cortical function, is impaired in rodents by subchronic (sc) treatment with the N-methyl-D-aspartate receptor antagonist, phencyclidine (PCP), a widely studied model of cognitive impairment in schizophrenia (CIS).

OBJECTIVE

The principal objective of this study was to determine the ability of serotonin (5-HT)1A partial agonism and 5-HT7 receptor antagonism to improve RL in scPCP-treated mice.

METHODS

Male C57BL/6J mice were trained on an operant RL (ORL) task, then received PCP, 10 mg/kg, or saline, bid, for 7 days, followed by a 7-day washout period.

RESULTS

scPCP significantly diminished the percent correct responding, increased total incorrect trials, and total incorrect responses, in the reversal phase performance of the ORL task. Pre-treatment with the selective 5-HT1A partial agonist, tandospirone, or the selective 5-HT7 antagonist, SB269970, but not the 5-HT7 agonist, AS 19, reversed the scPCP-induced deficit in RL. Pre-treatment with atypical antipsychotic drug lurasidone, which is a 5-HT1A partial agonist and 5-HT7 antagonist, as well as a 5-HT2A and dopamine (D)2 antagonist, also reversed RL deficit in the scPCP-treated mice. Furthermore, the selective 5-HT1A antagonist, WAY100635, blocked the ability of lurasidone to reverse the scPCP-induced RL deficit.

CONCLUSIONS

These results indicate that 5-HT7 antagonism and 5-HT1A partial agonism contribute to restoration of RL in scPCP-treated mice. It is suggested that these two mechanisms are effective in restoring RL by decreasing excessive GABAergic inhibition of cortical pyramidal neurons following withdrawal of scPCP treatment.

Chronic treatment with tandospirone, a serotonin 1A receptor partial agonist, inhibits psychosocial stress-induced changes in hippocampal neurogenesis and behavior

BACKGROUND

The 5-hydroxytryptamine (5-HT) 1A receptors are considered a potential target for the treatment of mental and neuropsychiatric disorders. Several studies have indicated that 5-HT1A receptor agonists increase hippocampal neurogenesis, which is implicated in the action mechanism of antidepressants. However, these agents have not been applied to humans due to intolerable side effects. We recently showed that chronic administration of tandospirone, a clinically available 5-HT1A receptor partial agonist, increased hippocampal neurogenesis dose-dependently. The present study was done to determine if chronic tandospirone treatment has antidepressant potential from the standpoint of hippocampal neurogenesis and behavior.

METHODS

Male Sprague-Dawley rats were intraperitoneally administered a vehicle or tandospirone (10mg/kg) once daily for 28 days. Two weeks after starting the injections, animals were exposed to intermittent social defeat (four times over two weeks). The effects of stress and tandospirone on the rodents׳ behavior were evaluated by the Novelty-Suppressed Feeding (NSF) test. The quantification of hippocampal neurogenesis was estimated using immunostaining with Ki-67 and doublecortin (DCX).

RESULTS

Chronic tandospirone treatment reversed the psychosocial stress-induced increase in the latency in the NSF test and decrease in the density of DCX-positive cells in the dentate gyrus of the dorsal and ventral hippocampus. However, no difference in the density of Ki-67-positive cells was observed between the vehicle- and tandospirone-administered groups.

LIMITATIONS

To clarify the antidepressant potential of TDS, the other behavioral tests for depression will be required.

CONCLUSIONS

Our findings suggest that tandospirone has antidepressant potential through an inhibiting effect on stress-induced changes in hippocampal neurogenesis.

Efficacy of tandospirone in patients with irritable bowel syndrome-diarrhea and anxiety

AIM: To investigate the efficacy of tandospirone in patients with irritable bowel syndrome-diarrhea (IBS-D) and anxiety in a prospective, randomized, controlled study.

METHODS: Two hundred patients with IBS-D and moderate anxiety were randomized to receive pinaverium and tandospirone (arm A) or pinaverium and placebo (arm B). Tandospirone or placebo was given thrice daily at a fixed dose of 10 mg and pinaverium was given thrice daily at a fixed dose of 50 mg. The duration of treatment was 8 wk. Patients were assessed for abdominal pain and diarrhea. Anxiety was evaluated using the Hamilton Rating Scale for Anxiety (HAM-A). The primary study endpoints were response rates for abdominal pain and diarrhea. The secondary study endpoints were response rates for anxiety. Adverse events were also evaluated.

RESULTS: One hundred and seventy of 200 patients (82 patients in arm A and 88 patients in arm B) completed the study. Demographic and baseline characteristics of the 200 participants were comparable in the two arms. At week 8, the overall response rate for abdominal pain and diarrhea was 52.0% for arm A and 37.0% for arm B (P < 0.05). The HAM-A score showed that the response rate was 61.0% for arm A and 21.0% for arm B (P < 0.01). The treatments were well tolerated and no significant adverse events were reported.

CONCLUSION: Tandospirone is effective and can be combined with pinaverium in IBS-D patients with anxiety.

Chronic Treatment with the 5-HT1A Receptor Partial Agonist Tandospirone Increases Hippocampal Neurogenesis

INTRODUCTION

A large-scale clinical trial, the Sequence Trial Alternatives to Relieve Depression (STAR*D) study, concluded that about one-third of the studied patients with major depressive disorder remitted during the initial treatment with selective serotonin reuptake inhibitors and that approximately half of the remitted subjects relapsed over a 1-year follow-up. The development of new therapeutic approaches with potent efficacy and good tolerability for the treatment of depressive disorders is of great importance. Adult hippocampal neurogenesis has been proposed to be important for understanding and treating depression and anxiety. The present study aimed to elucidate whether or not 5-hydroxytryptamine 1A (5-HT1A) receptor partial agonists have a potential therapeutic effect for the treatment of depressive and anxiety disorders, from the standpoint of neurogenesis.

METHODS

Male Sprague-Dawley rats were subcutaneously administered a vehicle or tandospirone (TDS) (1 or 10 mg/kg) once daily for 14 days. The effects of chronic TDS treatment on neurogenesis were evaluated on the day after the last injection. The quantification of hippocampal neurogenesis was estimated using immunostaining with doublecortin (DCX), a marker protein of newborn neurons.

RESULTS

Chronic TDS treatment resulted in a significant increase in the number of DCX-positive cells per volume of dentate gyrus in a dose-dependent manner.

CONCLUSION

The results strongly suggest that 5-HT1A receptor partial agonists would be useful and beneficial in the treatment of depressive and anxiety disorders through increased hippocampal neurogenesis.

Tandospirone reduces wasting and improves cardiac function in experimental cancer cachexia

BACKGROUND

Cancer cachexia is thought to be the cause of >20% of cancer related deaths. Symptoms of cancer cachexia patients include depression and anorexia significantly worsening their quality of life. Moreover, in rodent models of cancer cachexia atrophy of the heart has been shown to impair cardiac function. Here, we characterize the effects of the antidepressant and anxiolytic drug tandospirone on wasting, cardiac function and survival in experimental cancer cachexia.

METHODS

The well-established Yoshida hepatoma rat model was used and tumor-bearing rats were treated with 1mg/kg/d (LD), 10mg/kg/d (HD) tandospirone or placebo. Weight, body composition (NMR), cardiac function (echocardiography), activity and food intake were assessed. Noradrenalin and cortisol were measured in plasma and caspase activity in skeletal muscle.

RESULTS

Ten mg/kg/d tandospirone decreased the loss of body weight (p=0.0003) compared to placebo animals, mainly due to preservation of muscle mass (p<0.001), while 1mg/kg/d tandospirone was not effective. Locomotor activity (p=0.0007) and food intake (p=0.0001) were increased by HD tandospirone. The weight (p=0.0277) and function of heart (left ventricular mass, fractional shortening, stroke volume, ejection fraction, all p<0.05) were significantly improved. In the HD tandospirone group, plasma levels of noradrenalin and cortisol were significantly reduced by 49% and 52%, respectively, which may have contributed to the lower caspase activity in the gastrocnemius muscle. Most importantly, HD tandospirone significantly improved survival compared to placebo rats (HR: 0.34; 95% CI: 0.13-0.86; p=0.0495).

CONCLUSION

Tandospirone showed significant beneficial effects in the Yoshida hepatoma cancer cachexia model and should be further examined as a prospective drug for this syndrome.

Chronic treatment with tandospirone, a 5-HT(1A) receptor partial agonist, suppresses footshock stress-induced lactate production in the prefrontal cortex of rats

Serotonin 1A receptor (5-HT1A-R) agonists have been demonstrated to elicit antidepressant and anxiolytic effects. Lactate has been considered to play a major role in energy metabolism in the brain. Specifically, extracellular lactate concentrations (eLAC) have been suggested to reflect neural activity. Mild physical (e.g., handling) and non-physical (e.g., psychological) stressors have been shown to increase eLAC in several brain regions, including the medial prefrontal cortex (mPFC) and basolateral amygdala (BLA). Using in vivo microdialysis technique, we measured eLAC in the mPFC and BLA of rats under electric footshock stress to clarify the effect of repeated injection procedure (saline, once daily for 14 days) as a stressor on brain energy metabolism. Then, we examined the effect of chronic treatment with tandospirone, a 5-HT1A-R partial agonist, on eLAC during footshock stress in the mPFC. Footshock stress led to an increase in eLAC both in the mPFC and BLA in rats without injections. Repeated saline injection increased basal eLAC in the BLA, while footshock-induced lactate increment was reduced. In the mPFC, repeated saline injection did not affect basal eLAC and footshock-induced eLAC increments. Chronic treatment with tandospirone, at 0.2 and 1.0 mg/kg/day, but not 2.0 mg/kg/day, attenuated footshock stress-induced eLAC elevation in the mPFC. These observations suggest that eLAC in the BLA is sensitive to repeated exposure to physical stress. Data also indicate chronic treatment with tandospirone diminishes acute energy demands during neural activation in the mPFC. The implications of the present findings in relation to clinical efficacy of 5-HT1A agonists are discussed.

Emerging pharmacological therapy for functional dyspepsia

Functional dyspepsia (FD) is a multifactorial disease with complex underlying pathophysiology. To date, there is no established treatment for FD. This review summarizes recent progress in pharmacological therapy for the disease. A newly developed drug, acotiamide, is expected to improve symptoms of postprandial distress syndrome. Herbal medicines are also expected to become options for FD treatment.

Relationship between refractory functional dyspepsia and emotional disturbance and therapeutic action of tandospirone

AIM: To investigate the relationship between refractory functional dyspepsia (RFD) and emo-tional disturbance, and observe the therapeutic action of tandospirone.

METHODS: Thirty patients with RFD were included in this study. Based on symptomatic treatment, tandospirone was used for 6 wk. HAMD and HAMA scores were obtained before and after treatment. Then the mean value of HAMD and HAMA scores was calculated to evaluate the disease status. Meanwhile, the eight common symptoms of functional dyspepsia were scored.

RESULTS: Athymia and anxiety coexisted in 24 of 30 cases (80.0%). Pure athymia was found in 1 case (3.3%), and pure anxiety occurred in 5 cases (16.7%). The HAMD and HAMA scores, as well as the mean values of them, were significantly higher in RFD patients than those in the healthy controls (26.1 ± 6.2, 21.8 ± 4.1, 24.0 ± 5.6 vs 11.6 ± 3.8, 8.6 ± 2.3, 10.1 ± 3.5, all P < 0.01). The score for the eight common symptoms of functional dyspepsia were also markedly higher than that in the controls (11.3 ± 3.6 vs 8.7 ± 1.7, P < 0.01). The above scores were also significantly different before and after treatment (P < 0.01).

CONCLUSION: RFD patients have different degrees of emotional disturbance. Tandospirone can be used in the treatment of RFD.