The 5-hydroxytryptamine 2A receptor (5-HT_2AR) is one of the key targets in the development of novel antidepressants. To develop new antidepressants targeting the 5-HT_2A receptor, this study established a high-throughput screening method for drugs targeting the 5-HT_2A receptor based on the principle of detecting calcium flux signals. The immunofluorescence assay and western blotting were employed to evaluate receptor expression levels in the 5-HT_2AR-CHO cell line. The reaction system parameters, including cell seeding density, DMSO concentration, and dye incubation time, were optimized with Z'-factor and signal window values as evaluation indicators. The specificity, precision, stability, and applicability of the method were assessed. Results indicated that the 5-HT_2AR-CHO cell line stably expressed high levels of the 5-HT_2A receptor. The optimized screening method involved a reaction system with 10 000 cells/well, 0.2% DMSO, and 2 h incubation with Calcium 6 dye. The method demonstrated excellent specificity, with inter-batch precision below 10% for the detection of 5-hydroxytryptamine (5-HT) at low, medium, and high concentrations. Testing four compounds that target the 5-HT_2A receptor- agonists 2,5-dimethoxy-4-iodoamphetamine (DOI), 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT), and lysergic acid diethylamide (LSD), along with the antagonist MDL100907-yielded Z'-factors (at EC₈₀) greater than 0.85 and signal window values over 0.91. The EC₅₀ values of these compounds were in the nanomolar range, and their potency rank order aligned with previously reported data, confirming the reliability of the established method. When being applied to the detection of 38 known active compounds, the method efficiently identified 5-HT_2A receptor agonists and antagonists while showing no response to non-target compounds. In conclusion, this study successfully constructs a high-throughput screening approach for 5-HT_2A receptor-targeting drugs based on calcium flux signals. The method possesses strong specificity, high sensitivity, and robust stability, being suitable for screening antidepressants targeting the 5-HT_2A receptor.
High-Throughput Screening Assays/methods* ; Receptor, Serotonin, 5-HT2A/metabolism* ; Animals ; CHO Cells ; Cricetulus ; Calcium Signaling/drug effects* ; Antidepressive Agents/pharmacology* ; Humans ; Serotonin 5-HT2 Receptor Antagonists/pharmacology* ; Calcium/metabolism*

OBJECTIVE: To investigate the clinical effect and adverse reactions of dapoxetine hydrochloride versus paroxetine in the treatment of primary premature ejaculation by cross-comparison. METHODS: Based on the clinic-visit time, we equally randomized 148 patients with primary premature ejaculation into groups A and B for a cross-comparison test, the former treated with paroxetine at 20 mg once nightly and the latter with dapoxetine hydrochloride at 30 mg on demand, both for 6 successive weeks, during which we observed the therapeutic effects and adverse reactions. Following 4 weeks of drug discontinuance, we administered dapoxetine hydrochloride at 30 mg on demand for group A and paroxetine at 20 mg once nightly for group B, both for another 6 successive weeks, followed by observation and comparison of the therapeutic effects and adverse reactions. RESULTS: There were no statistically significant differences in the initial characteristics of the two groups of patients (P > 0.05). Compared with the baseline, the mean intra-vaginal ejaculation latency time (IELT) was dramatically improved after treatment in both groups A (4.43 min) and B (7.12 min), increased by 3.99% and 6.72%, respectively (P<0.001). The patients treated with paroxetine showed significantly longer IELT than those taking dapoxetine hydrochloride in both groups (P<0.001). Findings of the Premature Ejaculation Profile (PEP) and spouses' conditions indicated significant improvement after treatment in the average scores of the four indicators of PEP, that is, perceived control over ejaculation, ejaculation-related personal distress, satisfaction with sexual intercourse and ejaculation-related interpersonal difficulty, as well as in the overall experience and partner's satisfaction and orgasm frequency. Adverse reactions to medication were found in 20.8% of the cases in group A and 9.7% in group B, but none was serious. Preference survey following drug withdrawal revealed a preference for paroxetine (61.9%) over dapoxetine (26.8%), and that only a few of the patients thought of the two drugs as comparable or both ineffective. CONCLUSION In term of overall effectiveness, paroxetine was superior to dapoxetine in the treatment of primary premature ejaculation. And the patients obviously preferred the former to the latter, which might be partly attributed to the higher price of dapoxetine.
Humans ; Benzylamines/therapeutic use* ; Male ; Premature Ejaculation/drug therapy* ; Naphthalenes/therapeutic use* ; Paroxetine/therapeutic use* ; Adult ; Treatment Outcome ; Middle Aged ; Young Adult ; Selective Serotonin Reuptake Inhibitors/therapeutic use*

OBJECTIVES: To determine the pharmacological impact of hesperidin, the main component of Citri Reticulatae Pericarpium, on depressive behavior and elucidate the mechanism by which hesperidin treats depression, focusing on the gut-brain axis. METHODS: Fifty-four Sprague Dawley male rats were randomly allocated to 6 groups using a random number table, including control, model, hesperidin, probiotics, fluoxetine, and Citri Reticulatae Pericarpium groups. Except for the control group, rats in the remaining 5 groups were challenged with chronic unpredictable mild stress (CUMS) for 21 days and housed in single cages. The sucrose preference test (SPT), immobility time in the forced swim test (FST), and number in the open field test (OFT) were performed to measure the behavioral changes in the rats. Enzyme-linked immunosorbent assay was used to determine the levels of 5-hydroxytryptamine (5-HT) and brain-derived neurotrophic factor (BDNF) in brain tissue, and the histopathology was performed to evaluate the changes of colon tissue, together with sequencing of the V3-V4 regions of 16S rRNA gene on feces to explore the changes of intestinal flora in the rats. RESULTS: Compared to the control group, the rats in the model group showed notable reductions in body weight, SPF, and number in OFT (P<0.01). Hesperidin was found to ameliorate depression induced by CUMS, as seen by improvements in body weight, SPT, immobility time in FST, and number in OFT (P<0.05 or P<0.01). Regarding neurotransmitters, it was found that at a dose of 50 mg/kg hesperidin treatment upregulated the levels of 5-HT and BDNF in depressed rats (P<0.05). Compared to the control group, the colon tissue of the model group exhibited greater inflammatory cell infiltration, with markedly reduced numbers of goblet cells and crypts and were significantly improved following treatment with hesperidin. Simultaneously, the administration of hesperidin demonstrated a positive impact on the gut microbiome of rats treated with CUMS, such as Shannon index increased and Simpson index decreased (P<0.01), while the abundance of Pseudomonadota and Bacteroidota increased in the hesperidin-treated group (P<0.05). CONCLUSION The mechanism responsible for the beneficial effects of hesperidin on depressive behavior in rats may be related to inhibition of the expressions of BDNF and 5-HT and preservation of the gut microbiota.
Animals ; Hesperidin/therapeutic use* ; Rats, Sprague-Dawley ; Depression/drug therapy* ; Male ; Stress, Psychological/drug therapy* ; Brain/metabolism* ; Brain-Derived Neurotrophic Factor/metabolism* ; Serotonin/metabolism* ; Gastrointestinal Microbiome/drug effects* ; Behavior, Animal/drug effects* ; Rats ; Brain-Gut Axis/drug effects* ; Chronic Disease ; Colon/drug effects*

OBJECTIVE: To elucidate the mechanism of Banxia Houpo Decoction (BHD) in treating gastroesophageal reflux disease (GERD) by integrating and utilizing the compound analysis, network pharmacology, and empirical verification. METHODS: Ultra-high performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) was utilized to identify the primary compounds in BHD. Network pharmacology was employed to retrieve target genes. A GERD rat model was developed and 32 SD rats were randomly divided into model, BHD-L (3 g/kg), BHD-H (6 g/kg), and mosapride (0.75 mg/kg) groups using a random number table, 8 rats in each group. Eight rats without the construction of a GERD model were selected as the blank group. Esophageal damage was evaluated through visualization and histopathology evaluation. 5-hydroxytryptamine (5-HT) levels in serum and lower esophageal sphincter (LES) were determined by ELISA. LES contractility was measured with a force transducer, and serotonin transporter (SERT) and 5-HT4R expressions in LES were assessed by RT-PCR, Western blot, and immunofluorescence staining, respectively. RESULTS: UPLC-HRMS analysis identified 37 absorption peaks and 157 compounds in BHD. Functional enrichment identified SERT as a significant target for LES contractility. Histopathological findings indicated less severe esophageal mucosal damage in the BHD-H group compared with the model group. Although serum 5-HT levels showed no significant difference, 5-HT concentration in LES tissue was notably higher in the BHD-H group (P<0.05). Within the range from 10^-10 to 10^-7 mmol/L, LES contractility in the BHD-H and mosapride groups was significantly increased (P<0.05). Within the range from 3 × 10^-7 to 3 × 10^-6 mmol/L 5-HT, LES contractility in the BHD-H group was increased (P<0.05). No significant difference was detected within the range from 10^-5 to 10^-4 mmol/L 5-HT. Notably, SERT expression in the BHD-H group assessed by RT-PCR, Western blot, and immunofluorescence staining were significantly lower than that in the model group (all P<0.01); while 5-HT4R expression remained unchanged. CONCLUSION BHD may increase LES contractility by inhibiting SERT expression in LES tissue.
Animals ; Gastroesophageal Reflux/physiopathology* ; Drugs, Chinese Herbal/chemistry* ; Rats, Sprague-Dawley ; Network Pharmacology ; Male ; Serotonin/metabolism* ; Rats ; Disease Models, Animal ; Serotonin Plasma Membrane Transport Proteins/metabolism* ; Esophagus/drug effects*

Neuropathic pain, often featuring allodynia, imposes significant physical and psychological burdens on patients, with limited treatments due to unclear central mechanisms. Addressing this challenge remains a crucial unsolved issue in pain medicine. Our previous study, using protein kinase C gamma (PKCγ)-tdTomato mice, highlights the spinal feedforward inhibitory circuit involving PKCγ neurons in gating neuropathic allodynia. However, the regulatory mechanisms governing this circuit necessitate further elucidation. We used diverse transgenic mice and advanced techniques to uncover the regulatory role of the descending serotonin (5-HT) facilitation system on spinal PKCγ neurons. Our findings revealed that 5-HT neurons from the rostral ventromedial medulla hyperpolarize spinal inhibitory interneurons via 5-HT_2C receptors, disinhibiting the feedforward inhibitory circuit involving PKCγ neurons and exacerbating allodynia. Inhibiting spinal 5-HT_2C receptors restored the feedforward inhibitory circuit, effectively preventing neuropathic allodynia. These insights offer promising therapeutic targets for neuropathic allodynia management, emphasizing the potential of spinal 5-HT_2C receptors as a novel avenue for intervention.
Animals ; Neuralgia/physiopathology* ; Protein Kinase C/metabolism* ; Receptor, Serotonin, 5-HT2C/metabolism* ; Hyperalgesia/physiopathology* ; Mice, Transgenic ; Mice ; Spinal Cord/metabolism* ; Serotonin/metabolism* ; Male ; Neurons/metabolism* ; Mice, Inbred C57BL

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a severe dose-limiting adverse event of chemotherapy. Presently, the mechanism underlying the induction of CIPN remains unclear, and no effective treatment is available. In this study, through metabolomics analyses, we found that nab-paclitaxel therapy markedly increased serum serotonin [5-hydroxtryptamine (5-HT)] levels in both cancer patients and mice compared to the respective controls. Furthermore, nab-paclitaxel-treated enterochromaffin (EC) cells showed increased 5-HT synthesis, and serotonin-treated Schwann cells showed damage, as indicated by the activation of CREB3L3/MMP3/FAS signaling. Venlafaxine, an inhibitor of serotonin and norepinephrine reuptake, was found to protect against nerve injury by suppressing the activation of CREB3L3/MMP3/FAS signaling in Schwann cells. Remarkably, venlafaxine was found to significantly alleviate nab-paclitaxel-induced CIPN in patients without affecting the clinical efficacy of chemotherapy. In summary, our study reveals that EC cell-derived 5-HT plays a critical role in nab-paclitaxel-related neurotoxic lesions, and venlafaxine co-administration represents a novel approach to treating chronic cumulative neurotoxicity commonly reported in nab-paclitaxel-based chemotherapy.
Paclitaxel/toxicity* ; Animals ; Albumins/adverse effects* ; Serotonin/metabolism* ; Mice ; Humans ; Male ; Female ; Venlafaxine Hydrochloride/therapeutic use* ; Neurotoxicity Syndromes/metabolism* ; Middle Aged ; Schwann Cells/metabolism* ; Peripheral Nervous System Diseases/drug therapy* ; Antineoplastic Agents

OBJECTIVE: To observe the effects of Tiaoshu Anshen (regulating the hinge and calming the mind) acupuncture on sleep quality and serum levels of 5-hydroxytryptamine (5-HT) and dopamine (DA) in patients with chronic insomnia. METHODS: A total of 58 patients with chronic insomnia were randomly divided into an acupuncture group and a medication group, 29 cases in each group. Tiaoshu Anshen acupuncture was applied at Baihui (GV20) and bilateral Shenmen (HT7), Sanyinjiao (SP6), Benshen (GB13) in the acupuncture group, once a day, 1-day interval was taken after 6 consecutive days of treatment. Estazolam tablet was given orally before bed in the medication group, 1 mg each time. The 4-week treatment was required in both groups. Before and after treatment, the sleep quality was assessed by Pittsburgh sleep quality index (PSQI) and polysomnography (PSG), the serum levels of 5-HT and DA were detected by ELISA. RESULTS: After treatment, the item scores and total scores of PSQI were decreased compared with those before treatment in the two groups (P<0.05); in the acupuncture group, the scores of sleep quality, sleep latency, sleep time, sleep efficiency, sleep disorders and total score of PSQI were lower than those in the medication group (P<0.05). After treatment, the total sleep time (TST) was prolonged (P<0.05), the sleep latency (SL) and wake after sleep onset (WASO) were shortened (P<0.05), the sleep efficiency (SE%), percentage of non-rapid eye movement stage 3 (N3%), percentage of rapid eye movement stage (REM%) and serum levels of 5-HT were increased (P<0.05) compared with those before treatment; the percentage of non-rapid eye movement stage 1 (N1%), percentage of non-rapid eye movement stage 2 (N2%) and serum levels of DA were decreased (P<0.05) compared with those before treatment in the two groups. After treatment, in the acupuncture group, TST was longer, while SL and WASO were shorter than those in the medication group (P<0.05), SE%, N3%, REM% and serum level of 5-HT were higher, while N1%, N2% and serum level of DA were lower than those in the medication group (P<0.05). CONCLUSION Tiaoshu Anshen acupuncture may improve the sleep quality by regulating the serum neurotransmitter levels i.e. 5-HT and DA in patients with chronic insomnia.
Humans ; Sleep Initiation and Maintenance Disorders/physiopathology* ; Male ; Acupuncture Therapy ; Female ; Middle Aged ; Adult ; Serotonin/blood* ; Sleep Quality ; Acupuncture Points ; Dopamine/blood* ; Aged ; Neurotransmitter Agents/blood* ; Young Adult

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Hegu" (LI4) and "Taichong" (LR3) on DNA methylation of the solute carrier family 6 member 4 (SLC6A4) gene promoter region in the hippocampus of depressed rats, and to explore the potential antidepressant mechanism of EA. METHODS: Thirty male Sprague-Dawley rats were randomly divided into a blank group, a model group, a medication group, a 5-Azacytidine (5-AZA) group, and an EA group, 6 rats in each group. Depression models were established in the model group, the medication group, the 5-AZA group, and the EA group using chronic unpredictable mild stress (CUMS) combined with solitary housing. The medication group was treated with intragastric administration of fluoxetine hydrochloride capsules; the 5-AZA group was treated with intraperitoneal injection of 5-AZA; the EA group was treated with EA at bilateral "Hegu" (LI4) and "Taichong" (LR3), with disperse-dense wave, frequency of 2 Hz/100 Hz, and intensity of 1-1.2 mA, 20 min each session. All the treatment was given in three groups once daily for 21 consecutive days. Behavioral changes were evaluated by sucrose preference test, open field test, and novelty-suppressed feeding test. Serum levels of serotonin (5-HT), dopamine (DA), and norepinephrine (NE) were measured by ELISA. The expression of SLC6A4 and 5-HT1AR protein and mRNA in hippocampus was detected by Western blot and real-time quantitative PCR, respectively. DNA methylation status of the SLC6A4 promoter region in hippocampal tissue was analyzed by bisulfite sequencing PCR (BSP). RESULTS: Compared with the blank group, the model group showed decreased sucrose preference, reduced total locomotor distance, and prolonged latency to feeding (P<0.05), decreased serum 5-HT, DA, and NE levels (P<0.05), downregulated hippocampal SLC6A4 and 5-HT1AR protein and mRNA expression (P<0.05), and increased CpG site methylation rate of the SLC6A4 promoter region (P<0.05). Compared with the model group, the medication group, the 5-AZA group, and the EA group exhibited increased sucrose preference, increased total locomotor distance, shortened latency to feeding (P<0.05), elevated serum 5-HT, DA, and NE levels (P<0.05), upregulated hippocampal SLC6A4 and 5-HT1AR protein and mRNA expression (P<0.05), and reduced CpG site methylation rate of the SLC6A4 promoter (P<0.05). Compared with the medication group and the 5-AZA group, the EA group showed higher sucrose preference, greater total locomotor distance, shorter latency to feeding (P<0.05), and increased serum DA and NE levels (P<0.05). CONCLUSION EA could improve depressive behaviors in depressed rat models. The underlying mechanism may involve inhibition of SLC6A4 hypermethylation in the hippocampus on the serotonergic system, upregulation of SLC6A4 and 5-HT1AR protein and mRNA expression, and elevation of monoamine neurotransmitters such as 5-HT.
Animals ; Electroacupuncture ; Male ; Hippocampus/metabolism* ; Rats, Sprague-Dawley ; Rats ; Acupuncture Points ; DNA Methylation ; Depression/metabolism* ; Promoter Regions, Genetic ; Serotonin Plasma Membrane Transport Proteins/metabolism* ; Humans

To explore the anti-depression effect of Suanzaoren Decoction(SZRD), the regulatory effects on endogenous metabolites in the liver of rats with depression induced by chronic unpredictable mild stress(CUMS) were analyzed by using LC-MS metabolomics. The rats were randomly divided into normal control group, model group, low-dose SZRD group, high-dose SZRD group, and positive drug group. The CUMS depression model was replicated by applying a variety of stimuli, such as fasting and water deprivation, ice water swimming, hot water swimming, day and night reversal, tail clamping, and restraint for rats. Modeling and treatment were conducted for 56 days. The behavioral indexes of rats in each group, including body weight, open field test, sucrose preference test, and tail suspension test, were observed. Plasma samples and liver tissue samples were collected, and the contents of 5-hydroxytryptamine(5-HT), dopamine(DA), and norepinephrine(NE) in plasma were measured using enzyme-linked immunosorbent assay(ELISA). Meanwhile, the regulatory effects of SZRD on the liver metabolic profile of CUMS model rats were analyzed by the LC-MS metabolomics method. The results show that SZRD can significantly improve the depression-like behavior of CUMS model rats and increase the neurotransmitter levels of 5-HT, DA, and NE in plasma. A total of 24 different metabolites in the rats' liver are identified using the LC-MS metabolomics method, and SZRD can reverse 13 of these metabolites. Metabolic pathway analysis indicates that nine metabolic pathways are found to be significantly associated with depression, and in the low-dose SZRD group, four pathways can be regulated, including pentose phosphate pathway, purine metabolism, inositol phosphate metabolism, and sphingolipid metabolism. In the high-dose SZRD group, two metabolic pathways can be regulated, including sphingolipid metabolism and glycerol glycerophospholipid metabolism. Sphingolipid metabolism is a metabolic pathway that can be regulated by SZRD at different doses, so it is speculated that it may be the primary pathway through which SZRD can alleviate metabolic disturbances in the liver of CUMS model rats.
Animals ; Rats ; Drugs, Chinese Herbal/administration & dosage* ; Metabolomics ; Depression/metabolism* ; Male ; Liver/drug effects* ; Rats, Sprague-Dawley ; Antidepressive Agents/administration & dosage* ; Serotonin/blood* ; Humans ; Disease Models, Animal ; Behavior, Animal/drug effects*

This study aims to observe the mind-tranquilizing effect of Fushen Decoction on mice and investigate its effects on the 5-hydroxytryptamine(5-HT) system and γ-aminobutyric acid(GABA) in the brain of the mouse model of 4-chloro-DL-phenylalanine(PCPA)-induced insomnia. ICR mice were administrated with coffee(1 g·kg~(-1)) for 3 days, and the effects of Fushen Decoction(10, 20, and 40 g·kg~(-1)) on the autonomic activities of normal mice and coffee-treated mice were observed. Furthermore, the effects of Fushen Decoction on the autonomic activity and sleep induced by a suprathreshold dose of pentobarbital sodium in the mouse model of PCPA(350 mg·kg~(-1) for 3 consecutive days)-induced insomnia were observed. The levels of tryptophan hydroxylase(TPH), 5-hydroxytryptophan(5-HTP), and 5-HT in the serum, as well as those of 5-HTP and 5-HT in the brain stem, hippocampus, and cortex, were measured by enzyme-linked immunosorbent assay(ELISA). The fluorescence intensity of 5-HT in the raphe nucleus, hippocampus, and cortex was measured by the immunofluorescence method. The protein levels of tryptophan hydroxylase-2(TPH2) and 5-HT_(1A) receptor(5-HT_(1A)R) in the brain stem, hippocampus, and cortex were measured by Western blot. The levels of GABA in the hypothalamus, hippocampus, and cortex were measured by ELISA and immunohistochemistry methods. The results showed that Fushen Decoction(20, 40 g·kg~(-1)) reduced the number of autonomous activities in normal mice, coffee-treated mice, and the mouse model of PCPA-induced insomnia, and prolonged the duration of sleep induced by a suprathreshold dose of pentobarbital sodium in the mouse model. Fushen Decoction(20, 40 g·kg~(-1)) elevated the levels of TPH, 5-HTP, and 5-HT in the serum, and TPH2, 5-HTP, 5-HT, and 5-HT_(1A)R in the brain stem, hippocampus, and cortex, and up-regulated GABA expression in the hypothalamus, cortex, and hippocampus of the mouse model of PCPA-induced insomnia. In conclusion, Fushen Decoction(20, 40 g·kg~(-1)) exerted a mind-tranquilizing effect on mice by up-regulating the expression of TPH2, enhancing the 5-HT system, and elevating the GABA level in the brain.
Animals ; Serotonin/genetics* ; Sleep Initiation and Maintenance Disorders/genetics* ; Mice ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Mice, Inbred ICR ; gamma-Aminobutyric Acid/genetics* ; Disease Models, Animal ; Fenclonine/adverse effects* ; Tryptophan Hydroxylase/genetics* ; Brain/metabolism* ; Sleep/drug effects* ; Humans ; 5-Hydroxytryptophan/metabolism*