Mild Traumatic Brain Injury-Induced Augmented Postsurgical Pain Is Driven by Central Serotonergic Pain-Facilitatory Signaling.

BACKGROUND: Individuals recovering from mild traumatic brain injury (mTBI) have increased rates of acute and chronic pain. However, the mechanism through which mTBI triggers heightened pain responses and the link between mTBI and postsurgical pain remain elusive. Recent data suggest that dysregulated serotonergic pain-modulating circuits could be involved. We hypothesized that mTBI triggers dysfunction in descending serotonergic pain modulation, which exacerbates acute pain and delays pain-related recovery after surgery. METHODS: Using mouse models of mTBI and hindpaw incision for postsurgical pain in C57BL/6J mice, mechanical withdrawal thresholds were assessed throughout the postsurgical period. To determine whether mTBI leads to persistent alteration of endogenous opioid tone, mu-opioid receptors (MORs) were blocked with naloxone. Finally, the role of descending serotonergic signaling on postsurgical allodynia in animals with mTBI was examined using ondansetron (5-HT 3 receptor antagonist) or a serotonin-specific neurotoxin, 5,7-dihydroxytryptamine (5,7-DHT), to ablate descending serotonergic fibers. The treatment effects on withdrawal thresholds were normalized to baseline (percentage of maximum possible effect, MPE%), and analyzed using paired t -test or 2-way repeated-measures ANOVA with post hoc multiple comparisons. RESULTS: Post-mTBI mice demonstrated transient allodynia in hindpaws contralateral to mTBI, while no nociceptive changes were observed in sham-mTBI animals (mean difference, MD, MPE%, post-mTBI day 3: -60.9; 95% CI, -88.7 to -35.0; P < .001). After hindpaw incision, animals without mTBI exhibited transient allodynia, while mice with prior mTBI demonstrated prolonged postsurgical allodynia (MD-MPE% postsurgical day 14: -65.0; 95% CI, -125.4 to -4.5; P = .04). Blockade of MORs using naloxone transiently reinstated allodynia in mTBI animals but not in sham-mTBI mice (MD-MPE% post-naloxone: -69.9; 95% CI, -94.8 to -45.1; P < .001). Intrathecal administration of ondansetron reversed the allodynia observed post-mTBI and postincision in mTBI mice (compared to vehicle-treated mTBI mice, MD-MPE% post-mTBI day 3: 82.7; 95% CI, 58.5-106.9; P < .001; postsurgical day 17: 62.5; 95% CI, 38.3-86.7; P < .001). Both the acute allodynia after TBI and the period of prolonged allodynia after incision in mTBI mice were blocked by pretreatment with 5,7-DHT (compared to sham-mTBI mice, MD-MPE% post-mTBI day 3: 0.5; 95% CI, -18.5 to 19.5; P = .99; postsurgical day 14: -14.6; 95% CI, -16.7 to 45.9; P = .48). Similar behavioral patterns were observed in hindpaw ipsilateral to mTBI. CONCLUSIONS: Collectively, our results show that descending serotoninergic pain-facilitating signaling is responsible for nociceptive sensitization after mTBI and that central endogenous opioid tone opposes serotonin's effects. Understanding brain injury-related changes in endogenous pain modulation may lead to improved pain control for those with TBI undergoing surgery.

Serotonin type-3 receptor antagonists selectively kill melanoma cells through classical apoptosis, microtubule depolymerisation, ERK activation, and NF-κB downregulation.

Malignant melanoma is a highly metastatic tumour, resistant to treatment. Serotonin type-3 (5-HT3) receptor antagonists, such as tropisetron and ondansetron, are well-tolerated antiemetic drugs commonly used to prevent nausea caused by chemotherapy or radiotherapy. We investigated the anticancer effects of these drugs on melanoma cancer cell lines WM-266-4 and B16F10 with or without paclitaxel. We constructed IC50 curves and performed Chou-Talalay analysis, using data obtained with the MTT assay. Flow cytometry and fluorescent microscopy were used to examine characteristics of the cell cycle, cell death and cytoskeleton changes. Protein levels and activation were analysed by western blotting and molecular docking studies carried out. Data were analysed by one way ANOVA and post hoc testing. Ondansetron and tropisetron showed selective concentration-dependent cytotoxicity in melanoma cell lines WM-266-4 and B16F10. The effect in combination with paclitaxel was synergistic. The drugs did not cause cell cycle arrest but did promote characteristics of classical apoptosis, including accumulation of subG1 DNA, cleaved caspase-3, mitochondrial membrane permeability and phosphatidylserine exposure. As well, the cytosolic calcium level in the melanoma cells was enhanced, phosphorylated ERK1/2 induced and NF-κB inhibited. Finally, the formation of microtubules was shown to be impaired in melanoma cells treated with ondansetron or tropisetron. Docking studies were used to predict that these drugs could bind to the colchicine binding site on the tubulin molecule. Antiemetic drugs, already given in combination with chemotherapy, may enhance the cytotoxic effect of chemotherapy, following successful delivery to the tumour site.

2023 updated MASCC/ESMO consensus recommendations: prevention of nausea and vomiting following multiple-day chemotherapy, high-dose chemotherapy, and breakthrough nausea and vomiting.

PURPOSE: This review is an update of the MASCC/ESMO 2015 recommendations for the prophylaxis of acute and delayed nausea and vomiting induced by multiple-day chemotherapy, high-dose chemotherapy, and breakthrough nausea and vomiting. METHODS: A systematic literature search was conducted using PubMed from June 1, 2015, through February 1, 2023. RESULTS: We identified 56 references (16 were duplications or invalid), leaving 40 manuscripts for this search. The panel classified level I evidence (three manuscripts) and level II evidence (14 manuscripts). High-dose chemotherapy and stem cell transplant were discussed in four of these manuscripts, and multiple-day chemotherapy treatment in 15. Some manuscripts covered both topics. Additionally, a search for breakthrough nausea and vomiting resulted in 12 "hits." No new relevant studies were identified. CONCLUSIONS: The recommendations for patients receiving high-dose chemotherapy with stem cell transplants and patients undergoing multiple-day cisplatin were updated. For patients receiving high-dose chemotherapy for stem cell transplant, a combination of a 5-HT3 receptor antagonist with dexamethasone and aprepitant is recommended. Olanzapine could be considered part of the antiemetic regimen. Patients receiving multiple-day cisplatin should receive a 5-HT3 receptor antagonist plus dexamethasone plus aprepitant plus olanzapine. For patients experiencing breakthrough nausea and vomiting, the available evidence suggests using a single dose of olanzapine daily for 3 days.

Lactobacillus acidophilus regulates abnormal serotonin availability in experimental ulcerative colitis.

OBJECTIVES: Probiotics are known to play a beneficial role in curing irritable bowel syndrome such as ulcerative colitis. Commensal Lactobacillus species are thought to play a protective role against ulcerative colitis, as they restore homeostasis in intestinal disorders. Abnormal serotonin availability has been described in ulcerative colitis, but the underlying mechanism is still unclear. The aim of this study was to determine the anti-inflammatory role of Lactobacillus acidophilus (L. acidophilus) and its effect on serotonin expression. METHODS: Ulcerative colitis was created with the intrarectal administration of acetic acid. A total of 40 adult male rats were divided into five groups of eight rats as control, sham, experimental colitis, treatment (Colitis + L. acidophilus) and protective group (L. acidophilus + colitis). To evaluate the effects of L. acidophilus on serotonin expression in ulcerative colitis, this bacterial strain was administered orally to the rats with acetic acid-induced colitis. After oral administration of L. acidophilus for 14 days, serotonin content was biochemically measured and serotonin expression was evaluated immunohistochemically. RESULTS: The expression of serotonin and its protein content was significantly increased in colitis compared to the control and sham groups. Abnormal serotonin availability in the rats with acetic acid-induced colitis was significantly reduced by the L. acidophilus. CONCLUSIONS: In our study, it was observed that the amount of serotonin in the intestinal tissue increased excessively with ulcerative colitis. In addition, L.acidophilus has been found to reduce the abnormally increased amount of serotonin in the colon tissue, as well as reduce the inflammation in the intestinal tissue that occurs with ulcerative colitis. With our findings, it is predicted that probiotic application can be used as a treatment option in ulcerative colitis.

Flavonoids in Amomum tsaoko Crevost et Lemarie Ameliorate Loperamide-Induced Constipation in Mice by Regulating Gut Microbiota and Related Metabolites.

Amomum tsaoko (AT) is a dietary botanical with laxative properties; however, the active ingredients and mechanisms are still unclear. The active fraction of AT aqueous extract (ATAE) for promoting defecation in slow transit constipation mice is the ethanol-soluble part (ATES). The total flavonoids of ATES (ATTF) were the main active component. ATTF significantly increased the abundance of Lactobacillus and Bacillus and reduced the dominant commensals, such as Lachnospiraceae, thereby changing the gut microbiota structure and composition. Meanwhile, ATTF changed the gut metabolites mainly enriched in pathways such as the serotonergic synapse. In addition, ATTF increased the serum serotonin (5-HT) content and mRNA expression of 5-hydroxytryptamine receptor 2A (5-HT2A), Phospholipase A2 (PLA2), and Cyclooxygenase-2 (COX2), which are involved in the serotonergic synaptic pathway. ATTF increased Transient receptor potential A1 (TRPA1), which promotes the release of 5-HT, and Myosin light chain 3(MLC3), which promotes smooth muscle motility. Notably, we established a network between gut microbiota, gut metabolites, and host parameters. The dominant gut microbiota Lactobacillus and Bacillus, prostaglandin J2 (PGJ2) and laxative phenotypes showed the most significant associations. The above results suggest that ATTF may relieve constipation by regulating the gut microbiota and serotonergic synaptic pathway and has great potential for laxative drug development in the future.

The Effects of the Heat Shock Protein 90 Inhibitor 17-Allylamino-17-Demethoxygeldanamycin, Cannabinoid Agonist WIN 55,212-2, and Nitric Oxide Synthase Inhibitor Nω-Nitro-L-Arginine Methyl Ester Hydrochloride on the Serotonin and Dry Skin-Induced Itch.

INTRODUCTION: In many types of itch, the interaction between immune system cells, keratinocytes, and sensory nerves involved in the transmission of itch is quite complex. Especially for patients with chronic itching, current treatments are insufficient, and their quality of life deteriorates significantly. OBJECTIVE: In this study, we aimed to investigate the role of the heat shock protein 90 (Hsp90) inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG), cannabinoid agonist WIN 55,212-2, and nitric oxide (NO) synthase inhibitor Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME) in pruritus. METHODS: We created a serotonin (5-HT)-induced (50 µg/µL/mouse, i.d.) acute and acetone-ether-water (AEW)-induced chronic itching models. 17-AAG (1, 3, and 5 mg/kg, intraperitoneally [i.p.]), WIN 55,212-2 (1 mg/kg, i.p.), and L-NAME (1 mg/kg, i.p.) were applied to Balb/c mice. RESULTS: We found that 17-AAG suppressed the scratches of mice, depending on the dose. The itch behavior was reduced by WIN 55,212-2, but L-NAME showed no antipruritic effect at the administered dose. The combined application of these agents in both pruritus models showed synergism in terms of the antipruritic effect. Our results showed that NO did not play a role in the antipruritic effect of WIN 55,212-2 and 17-AAG. Increased plasma IgE levels with AEW treatment decreased with the administration of 17-AAG (5 mg/kg, i.p.) and WIN 55,212-2. CONCLUSION: These results demonstrate that Hsp90 may play a role in the peripheral pathway of pruritus, and cannabinoid agonists and Hsp90 inhibitors can be used together in the treatment of pruritus.

Antipsychotic- and Anxiolytic-like Properties of a Multimodal Compound JJGW08 in Rodents.

Schizophrenia is a chronic mental illness, which remains difficult to treat. A high resistance to the available therapies, their insufficient efficacy, and numerous side effects are the reasons why there is an urgent need to develop new antipsychotics. This study aimed to assess the antipsychotic-like effects of JJGW08, a novel arylpiperazine alkyl derivative of salicylamide, in rodents. First, considering the JJGW08 receptor profile, we investigated the compound's intrinsic activity towards dopamine D2 and serotonin 5-HT1A, 5-HT2A, and 5-HT7 receptors using functional assays. Next, we assessed the effect of JJGW08 on MK-801- and amphetamine-induced hyperlocomotion, its risk of inducing catalepsy and impairing motor coordination, as well as the anxiolytic-like effects in the four-plate and marble burying tests in mice. Finally, we investigated the antipsychotic-like properties of JJGW08 in rats using MK-801-induced hyperlocomotion and prepulse inhibition tests. We found that JJGW08 showed antagonistic properties at dopamine D2 and serotonin 5-HT1A, 5-HT2A, and 5-HT7 receptors. However, the effect on the 5-HT2A and 5-HT7 receptors was very weak. Moreover, the tested compound showed an antipsychotic-like effect in MK-801- and amphetamine-induced hyperlocomotion but not in a prepulse inhibition test in rats. Notably, JJGW08 demonstrated anxiolytic-like properties in both behavioral tests. Importantly, the compound did not induce catalepsy or motor coordination impairment in mice at antipsychotic-like doses. Our study suggests it is worth searching for new potential antipsychotics among arylpiperazine alkyl derivatives of salicylamide.

[Role of hyperglycemia-induced 5-hydroxytryptamine degradation of hepatic stellate cells in hepatic inflammation and fibrosis induced by type 2 diabetes mellitus].

OBJECTIVE: To explore the role of 5-hydroxytryptamine (5-HT) in type 2 diabetes mellitus (T2DM)-related hepatic inflammation and fibrosis. METHODS: Male C57BL/6J mice were used to establish T2DM model by high-fat diet feeding combined with intraperitoneal injection of streptozotocin. Then, the mice with hyperglycemia were still fed with high-fat diet for nine weeks, and treated with or without 5-HT2A receptor (5-HT2AR) antagonist sarpogrelate hydrochloride (SH) and 5-HT synthesis inhibitor carbidopa (CDP) (alone or in combination). To observe the role of 5-HT in the myofibroblastization of hepa-tic stellate cells (HSCs), human HSCs LX-2 were exposed to high glucose, and were treated with or without SH, CDP or monoamine oxidase A (MAO-A) inhibitor clorgiline (CGL). Hematoxylin & eosin and Masson staining were used to detect the pathological lesions of liver tissue section, immunohistochemistry and Western blot were used to analyze protein expression, biochemical indicators were measured by ELISA or enzyme kits, and levels of intracellular reactive oxygen species (ROS) were detected by fluorescent probe. RESULTS: There were up-regulated expressions of 5-HT2AR, 5-HT synthases and MAO-A, and elevated levels of 5-HT in the liver of the T2DM mice. In addition to reduction of the hepatic 5-HT levels and MAO-A expression, treatment with SH and CDP could effectively ameliorate liver lesions in the T2DM mice, both of which could ameliorate hepatic injury and steatosis, significantly inhibit the increase of hepatic ROS (H2O2) levels to alleviate oxidative stress, and markedly suppress the production of transforming growth factor ß1 (TGF-ß1) and the development of inflammation and fibrosis in liver. More importantly, there was a synergistic effect between SH and CDP. Studies on LX-2 cells showed that high glucose could induce up-regulation of 5-HT2AR, 5-HT synthases and MAO-A expression, increase intracellular 5-HT level, increase the production of ROS, and lead to myofibroblastization of LX-2, resulting in the increase of TGF-ß1 synthesis and production of inflammatory and fibrosis factors. The effects of high glucose could be significantly inhibited by 5-HT2AR antagonist SH or be markedly abolished by mitochondrial 5-HT degradation inhibitor CGL. In addition, SH significantly suppressed the up-regulation of 5-HT synthases and MAO-A induced by high glucose in LX-2. CONCLUSION: Hyperglycemia-induced myofibroblastization and TGF-ß1 production of HSCs, which leads to hepatic inflammation and fibrosis in T2DM mice, is probably due to the up-regulation of 5-HT2AR expression and increase of 5-HT synthesis and degradation, resulting in the increase of ROS production in mitochondria. Among them, 5-HT2AR is involved in the regulation of 5-HT synthases and MAO-A expression.

Dexfenfluramine and Pergolide Cause Heart Valve Disease via Valve Metabolic Reprogramming and Ongoing Matrix Remodeling.

Several clinical reports indicate that the use of amphetaminic anorectic drugs or ergot derivatives could cause valvular heart disease (VHD). We sought to investigate whether valvular lesions develop in response to long-term oral administration of these drugs and to identify drug-targeted biological processes that may lead to VHD. Treatment of New Zealand White rabbits with pergolide, dexfenfluramine, or high-dose serotonin for 16 weeks induced valvular alterations characterized by extracellular matrix remodeling. Transcriptome profiling of tricuspid valves using RNA sequencing revealed distinct patterns of differentially expressed genes (DEGs) that clustered according to the different treatments. Genes that were affected by the three treatments were functionally enriched for reduced cell metabolism processes. The two drugs yielded more changes in gene expression than serotonin and shared most of the DEGs. These DEGs were mostly enriched for decreased biosynthetic processes, increased cell-matrix interaction, and cell response to growth factors, including TGF-ß, which was associated with p38 MAPK activation. Treatment with pergolide specifically affected genes involved in homeostasis, which was corroborated by the activation of the master regulator of cell energy homeostasis, AMPK-α, as well as decreased levels of metabolism-related miR-107. Thus, both pergolide and dexfenfluramine may cause VHD through valve metabolic reprogramming and matrix remodeling.

Responses of thalamic neurons to itch- and pain-producing stimuli in rats.

Understanding of processing and transmission of information related to itch and pain in the thalamus is incomplete. In fact, no single unit studies of pruriceptive transmission in the thalamus have yet appeared. In urethane-anesthetized rats, we examined responses of 66 thalamic neurons to itch- and pain- inducing stimuli including chloroquine, serotonin, ß-alanine, histamine, and capsaicin. Eighty percent of all cells were activated by intradermal injections of one or more pruritogens. Forty percent of tested neurons responded to injection of three, four, or even five agents. Almost half of the examined neurons had mechanically defined receptive fields that extended onto distant areas of the body. Pruriceptive neurons were located within what appeared to be a continuous cell column extending from the posterior triangular nucleus (PoT) caudally to the ventral posterior medial nucleus (VPM) rostrally. All neurons tested within PoT were found to be pruriceptive. In addition, neurons in this nucleus responded at higher frequencies than did those in VPM, an indication that PoT might prove to be a particularly interesting region for additional studies of itch transmission. NEW & NOTEWORTHY Processing of information related to itch within in the thalamus is not well understood, We show in this, the first single-unit electrophysiological study of responses of thalamic neurons to pruritogens, that itch-responsive neurons are concentrated in two nuclei within the rat thalamus, the posterior triangular, and the ventral posterior medial nuclei.

Specific patterns of spinal metabolites underlying α-Me-5-HT-evoked pruritus compared with histamine and capsaicin assessed by proton nuclear magnetic resonance spectroscopy.

The mechanism behind itching is not well understood. Proton nuclear magnetic resonance (1H-NMR) spectroscopic analysis of spinal cord extracts provides a quick modality for evaluating the specific metabolic activity of α-Me-5-HT-evoked pruritus mice. In the current study, four groups of young adult male C57Bl/6 mice were investigated; one group treated with saline, while the other groups intradermally injected with α-Me-5-HT (histamine independent pruritogen), histamine (histamine dependent pruritogen) and capsaicin (algogenic substance), respectively. The intradermal microinjection of α-Me-5-HT and histamine resulted in a dramatic increase in the itch behavior. Furthermore, the results of NMR studies of the spinal cord extracts revealed that the metabolites show very different patterns for these different drugs, especially when comparing α-Me-5-HT and capsaicin. All the animals in the groups of α-Me-5-HT and capsaicin were completely separated using the metabolite parameters and principal component analysis. For α-Me-5-HT, the concentrations of glutamate, GABA, glycine and aspartate increased significantly, especially for GABA (increased 17.2%, p=0.008). Furthermore, the concentration of NAA increased, but there was no significant difference (increased 11.3%, p=0.191) compared to capsaicin (decreased 29.1%, p=0.002). Thus the application of magnetic resonance spectroscopy technique, coupled with statistical analysis, could further explain the mechanism behind itching evoked by α-Me-5-HT or other drugs. It can thus improve our understanding of itch pathophysiology and pharmacological therapies which may contribute to itch relief.

Possible Parkinson's Disease Induced by Chronic Manganese Supplement Ingestion.

OBJECTIVE: The objective is to report a case of possible neurotoxicity resulting from an incorrect dietary supplement for osteoporosis taken at a toxic dose. SUMMARY: The case study examined here is a 37-year-old African-American female who consumed excessive manganese over a period of years, resulting in Parkinson's disease (PD). This patient was referred to the pharmacist pharmacotherapy service by a neurology physician. PD has been shown in the medical literature to be caused by chronic exposure to high levels of manganese. It may be concluded that daily doses of manganese well above the upper limit of 9 mg per day were taken by this patient for an extended period of time, possibly causing PD via manganism. CONCLUSION: This case illustrates the unknown risks taken by patients who use excessive amounts of over-the-counter herbals and supplements and how pharmacists can assist patients and physicians in the proper use of these popular products. ABBREVIATIONS: AI = Adequate intake, EMS = Eosinophilia myalgia syndrome, MTM = Medication therapy management, UL = Tolerable upper limit.

Exposure to serotonin adversely affects oligodendrocyte development and myelination in vitro.

Serotonin (5-hydroxytryptamine, 5-HT) has been implicated to play critical roles in early neural development. Recent reports have suggested that perinatal exposure to selective serotonin reuptake inhibitors (SSRIs) resulted in cortical network miswiring, abnormal social behavior, callosal myelin malformation, as well as oligodendrocyte (OL) pathology in rats. To gain further insight into the cellular and molecular mechanisms underlying SSRIs-induced OL and myelin abnormalities, we investigated the effect of 5-HT exposure on OL development, cell death, and myelination in cell culture models. First, we showed that 5-HT receptor 1A and 2A subtypes were expressed in OL lineages, using immunocytochemistry, Western blot, as well as intracellular Ca(2+) measurement. We then assessed the effect of serotonin exposure on the lineage development, expression of myelin proteins, cell death, and myelination, in purified OL and neuron-OL myelination cultures. For pure OL cultures, our results showed that 5-HT exposure led to disturbance of OL development, as indicated by aberrant process outgrowth and reduced myelin proteins expression. At higher doses, such exposure triggered a development-dependent cell death, as immature OLs exhibited increasing susceptibility to 5-HT treatment compared to OL progenitor cells (OPC). We showed further that 5-HT-induced immature OL death was mediated at least partially via 5-HT2A receptor, since cell death could be mimicked by 5-HT2A receptor agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride, (±)-2,5-dimethoxy-4-iodoamphetamine hydrochloride, but atten-uated by pre-treatment with 5-HT2A receptor antagonist ritanserin. Utilizing a neuron-OL myelination co-culture model, our data showed that 5-HT exposure significantly reduced the number of myelinated internodes. In contrast to cell injury observed in pure OL cultures, 5-HT exposure did not lead to OL death or reduced OL density in neuron-OL co-cultures. However, abnormal patterns of contactin-associated protein (Caspr) clustering were observed at the sites of Node of Ranvier, suggesting that 5-HT exposure may affect other axon-derived factors for myelination. In summary, this is the first study to demonstrate that manipulation of serotonin levels affects OL development and myelination, which may contribute to altered neural connectivity noted in SSRIs-treated animals. The current in vitro study demonstrated that exposure to high level of serotonin (5-HT) led to aberrant oligodendrocyte (OL) development, cell injury, and myelination deficit. We propose that elevated extracellular serotonin levels in the fetal brain, such as upon the use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy, may adversely affect OL development and/or myelination, thus contributing to altered neural connectivity seen in Autism Spectrum Disorders. OPC = oligodendrocyte progenitor cell.

Serotonin syndrome: fentanyl and selective serotonin reuptake inhibitor interactions.

Serotonin syndrome is a rare but potentially fatal adverse drug reaction associated with increased serotonergic activity in the central nervous system. It is characterized by a triad of symptoms, which include altered mental status, neuromuscular hyperactivity, and autonomic instability or hyperactivity. Due to the potential of rapid onset, it is important for clinicians to recognize the signs and symptoms of serotonin syndrome. Serotonin syndrome symptoms may resemble other conditions. Although this article focuses on serotonin syndrome as a result of an adverse interaction of selective serotonin reuptake inhibitors (SSRI) and fentanyl, it is important for not only anesthesia professionals, but all clinicians--such as those in emergency medicine and critical care--to be aware of this syndrome and its management. This article discusses the clinical manifestations of the serotonin syndrome and highlights reported cases of serotonin syndrome specifically related to an interaction between SSRIs and fentanyl, a commonly used opioid in anesthesia practice.

[Osteoporosis correction in experiment].

Osteoporosis is simulated in rats by chronic administration of omeprazole or serotonin for 6 months; investigated bone status in the model of liver fibrosis and the administration of serotonin against liver fibrosis. The following experimental groups of rats: with bilateral ovariectomy, with bilateral ovariectomy and administration of omeprazole, with the introduction of serotonin, with serotonin administration and bilateral ovariectomy, with model of liver fibrosis, with liver fibrosis model and administration of serotonin were used. The content of Ca, P, alkaline phosphatase, albumin, serum creatinine, and the content of Ca, P, Mg andFe in the bone was determined. It was found that the administration of mesenchymal stromal cells reduces the severity of osteoporosis. The effects of alfacalcidol on experimental osteoporosis was investigated. Introduction of alfacalcidol in all experimental groups increased the bone formation.

Retrospective analysis of real-world prescribing data for managing cisplatin-based chemotherapy-induced nausea and vomiting in China.

BACKGROUND: The current utilization of neurokinin-1 receptor antagonists (NK1RAs) and the impact of updated guidelines on prescription patterns of antiemetic drugs among Chinese patients receiving highly emetogenic chemotherapy (HEC) remain undetermined. This study aims to analyze the present situation of Chinese cancer patients using antiemetic drugs and assess the appropriateness of antiemetic regimens. METHODS: Prescription data were collected between January 2015 and December 2020 from cancer patients receiving cisplatin-based chemotherapy at 76 hospitals in six major cities in China. Trends in the use of antiemetic drugs, prescribing patterns and adherence to antiemetic guidelines were assessed. RESULTS: Among the 108,611 patients included in this study, 6 classes and 17 antiemetic drugs were identified as monotherapy or combination therapy in 93,872 patients (86.4%), whereas 14,739 patients (13.6%) were administered no antiemetic treatment. 5-hydroxytryptamine 3 receptor antagonists (5-HT3RAs) and glucocorticoids were the two most frequently used classes of antiemetics, followed by metoclopramide. NK1RAs were underused across the six cities, only 9332 (8.6%) and 1655 (1.5%) cisplatin-based treatments were prescribed aprepitant and fosaprepitant, respectively. Prescriptions of olanzapine and lorazepam were very low throughout the study period. In prescribing patterns of antiemetic drugs, dual combination regimens were the most common (40.0%), followed by triple combination therapy and monotherapy (25.8% and 15.1%, respectively). Overall, the adherence to antiemetic guidelines for patients undergoing cisplatin-based regimens was only 8.1% due to inadequate prescription of antiemetic drugs. Finally, our study also revealed that 5-HT3RAs and glucocorticoids were overprescribed in 8.8% and 1.6% of patients, respectively. CONCLUSIONS: The current study reveals suboptimal utilization of recommended antiemetic drugs for managing cisplatin-based HEC-induced nausea and vomiting in China. Improving the management of CINV is crucial, and these findings provide valuable insights into optimizing antiemetic drug practices.

Effect of transcutaneous electrical stimulation on nociception and edema induced by peripheral serotonin.

Transcutaneous electrical nerve stimulation (TENS) is defined as the application of an electrical current to the skin through surface electrodes for pain relief. Various theories have been proposed in order to explain the analgesic mechanism of TENS. Recent studies have demonstrated that part of this analgesia is mediated through neurotransmitters acting at peripheral sites. The aim of this study was to investigate the effects of low frequency (LF: 10 HZ) TENS and high frequency (HF: 130 HZ) TENS on hyperalgesia and edema when applied before the serotonin (5-HT) administered into the rat paw. LF and HF TENS were applied to the right paw for 20 min, and 5-HT was administered immediately after TENS. The Hargreaves method was used to measure nociception, while the hydroplethysmometer (Ugo Basile®) was used to measure edema. Neither HF nor LF TENS inhibited 5-HT-induced edema. However, LF TENS, but not HF TENS, completely reduced 5-HT-induced hyperalgesia. Pre-treatment of the paw with naltrexone, prior to application of TENS, (Nx: 50 µg; I.pl.) showed a complete blockade of the analgesic effect induced by low frequency TENS. Thus, our results confirmed the lack of an anti-inflammatory effect through the use of TENS as well as the participation of peripheral endogenous opioid receptors in LF TENS analgesia in addition to its central action.

Reducing Inappropriate Simultaneous Ordering of Heparin Antibody and Serotonin Release Assays.

INTRODUCTION: A 4T score with intermediate or high probability of heparin-induced thrombocytopenia prompts ordering of anti-platelet 4 heparin complex. If positive, a serotonin release assay (SRA) is recommended to confirm diagnosis. Despite these recommendations, overtesting of both anti-platelet 4 and SRA is highly prevalent. METHODS: This was a quality improvement initiative using two forms of clinical decision support across 11 acute care hospitals. First, a 4T calculator was incorporated into anti-platelet 4 orders. Second, a Best Practice Advisory fired when anti-platelet 4 and SRA were ordered simultaneously, prompting the provider to remove the SRA order. Data were analyzed by a quasi-experimental interrupted time series linear regression comparing weekly average laboratory tests per 1,000 patient-days pre- and postintervention. RESULTS: Average ordering frequency of anti-platelet 4 changed from 0.508 to 0.510 per 1,000 patient-days (0.5%, p = 0.42) without significant slope or level differences. Average ordering frequency of SRA decreased from 0.430 to 0.289 per 1,000 patient-days (32.8%, p < 0.001) with a significant level difference of -0.128 orders per 1,000 patient-days (-31.2%, p < 0.05). CONCLUSION: A simultaneous Best Practice Advisory was effective in reducing SRA orders, but not anti-platelet 4 orders.

Hypothermia as a Possible Symptom of Serotonin Toxicity: A Case Report.

Background There are three commonly used sets of criteria to diagnose serotonin syndrome and all three diagnostic tools have all been shown to have shortcomings that do not fully encompass the possible symptoms of serotonin toxicity. Objective To describe a case of an atypical presentation of possible drug-induced serotonin syndrome, characterized by hypothermia, night sweats, muscle tremors, and confusion. Setting A rural and medically underserved area in eastern Washington State. Practice Description This patient case was identified as a part of a project to identify and intervene with complex and high-risk patients from local rural and underserved populations. The pharmacist identified the symptoms of possible drug-induced serotonin syndrome during a comprehensive medication review with the patient. Results The pharmacist identified a possible case of drug-induced serotonin syndrome and made a recommendation to the patient's physician that led to discontinuation of both fluoxetine and trazodone. At the follow-up visit, the patient reported that his symptoms had resolved completely. Discussion The three sets of diagnostic criteria for serotonin syndrome all include fever as a symptom, but do not list hypothermia. Effects at various 5-HT receptors and receptor subtypes have been linked to symptoms often seen in serotonin syndrome, but there are gaps in the currently used diagnostic criteria. Conclusion Pharmacists' comprehensive review of medications can allow identification of symptoms, such as hypothermia to identify possible serotonin syndrome.