NK1 Receptor Antagonist Research Articles

Effect of endogenous substance P on visceral afferent signal integration in the nucleus tractus solitaries of rat brainstem slices

In the first synapse of the blood-pressure-regulating pathway, a neurokinin (NK) family peptide substance P (SP) is release with an excitatory neurotransmitter, glutamate, to enhance the sensitivity of the baroreflex responses. However, the underlying mechanisms of action are not yet well understood. The effects of NK receptor antagonists and agonists on solitary tract stimulation-evoked excitatory postsynaptic responses were recorded using whole-cell patch-clamp recordings of neurons in the medial portion of the nucleus tractus solitarius (mNTS) in the brainstem. SP reduced the amplitude of the evoked excitatory postsynaptic currents (eEPSCs) and shifted the holding current inward, in a dose-dependent manner. The concentrations of SP needed to induce such responses were different between capsaicin-sensitive unmyelinated (C-type) and capsaicin-resistant myelinated (A-type) neurons. The perfusion of a NK1 receptor antagonist, sendide, reduced the amplitude of eEPSCs in all tested neurons but did not affect the levels of the holding current. A Neurokinin type 1 receptor (NK1 receptor) agonist, [Sar9, Met(O2)11]-SP, reduced the amplitude of the eEPSCs and shifted the holding current inward in capsaicin-resistant neurons; however, it failed to induce any significant changes in the capsaicin-sensitive neurons. Furthermore, a selective Neurokinin type 3 receptor (NK3 receptor) antagonist, SB223412, failed to induce any changes in any tested neuron. In current-clamp experiments, sendide reduced solitary tract (ST)-stimulation evoked firing of action potentials in both A- and C-type neurons. [Sar9, Met(O2)11]-SP suppressed the firing of the action potentials in C-type but not A-type neurons. In spontaneous synaptic recordings, SP reduced frequency of the sEPSCs in CAP sensitive neuron but NK1 agonist reduced at capsaicin resistant neurons. Taken together, the findings show that ST activation leads to the co-transmission of SP and glutamate and enhances baroreflex sensitivity by potentiating the amplitude of eEPSC in an NK1 receptor activity-dependent manner.

Substance P and Neurokinin-1 Receptor System in Thyroid Cancer: Potential Targets for New Molecular Therapies.

In recent years, numerous approaches have been developed to comprehend the molecular alterations underlying thyroid cancer (TC) oncogenesis and explore novel therapeutic strategies for TC. It is now well established that the neurokinin-1 receptor (NK-1R) is overexpressed in cancer cells and that NK-1R is essential for the viability of cancer cells. The binding of substance P (SP) to NK-1R in neoplastic cells plays a pivotal role in cancer progression by promoting neoplastic cell growth, protecting tumor cells from apoptosis, triggering invasion and metastasis through the enhanced migration of cancer cells, and stimulating endothelial cell proliferation for tumor angiogenesis. Remarkably, all types of human TC (papillary, follicular, medullary, anaplastic), as well as metastatic lesions, exhibit the overexpression of SP and NK-1R compared to the normal thyroid gland. TC cells synthesize and release SP, which exerts its multiple functions through autocrine, paracrine, intracrine, and neuroendocrine processes, including the regulation of tumor burden. Consequently, the secretion of SP from TC results in increased SP levels in plasma, which are significantly higher in TC patients compared to controls. Additionally, NK-1R antagonists have demonstrated a dose-dependent antitumor action. They impair cancer cell proliferation on one side and induce apoptosis of tumor cells on the other side. Furthermore, it has been demonstrated that NK-1R antagonists inhibit neoplastic cell migration, thereby impairing both invasiveness and metastatic abilities, as well as angiogenesis. Given the consistent overexpression of NK-1R in all types of TC, targeting this receptor represents a promising therapeutic approach for TC. Therefore, NK-1R antagonists, such as the drug aprepitant, may represent novel drugs for TC treatment.

H2O2 enhances the spontaneous phasic contractions of isolated human-bladder strips via activation of TRPA1 channels on sensory nerves and the release of substance P and PGE2

Several studies have indicated that reactive oxygen species (ROS) can lead to detrusor overactivity (DO), but the underlying mechanisms are not known. Hydrogen dioxide (H2O2) is used commonly to investigate the effects of ROS. In present study, we investigated the effects of H2O2 on phasic spontaneous bladder contractions (SBCs) of isolated human-bladder strips (iHBSs) and the underlying mechanisms. Samples of bladder tissue were obtained from 26 patients undergoing cystectomy owing to bladder cancer. SBCs of iHBSs were recorded in organ-bath experiments. H2O2 (1μM–10mM) concentration-dependently increased the SBCs of iHBSs. These enhancing effects could be mimicked by an agonist of transient receptor potential (TRP)A1 channels (allyl isothiocyanate) and blocked with an antagonist of TRPA1 channels (HC030031; 10 μM). H2O2 induced enhancing effects also could be attenuated by desensitizing sensory afferents with capsaicin (10 μM), blocking nerve firing with TTX (1 μM), blocking neurokinin effects with NK2 receptor antagonist (SR48968, 10 μM), and blocking PGE2 synthesis with indomethacin (10 μM), respectively. Our study: (i) suggests activation of TRPA1 channels on bladder sensory afferents, and then release of substance P or PGE2 from sensory nerve terminals, contribute to the H2O2-induced enhancing effects on SBCs of iHBSs; (ii) provides insights for the mechanisms underlying ROS leading to DO; (iii) indicates that targeting TRPA1 channels might be the promising strategy against overactive bladder in conditions associated with excessive production of ROS.

Insights into the genetics of menopausal vasomotor symptoms: genome-wide analyses of routinely-collected primary care health records

BackgroundVasomotor symptoms (VMS) can often significantly impact women’s quality of life at menopause. In vivo studies have shown that increased neurokinin B (NKB) / neurokinin 3 receptor (NK3R) signalling contributes to VMS, with previous genetic studies implicating the TACR3 gene locus that encodes NK3R. Large-scale genomic analyses offer the possibility of biological insights but few such studies have collected data on VMS, while proxy phenotypes such as hormone replacement therapy (HRT) use are likely to be affected by changes in clinical practice. We investigated the genetic basis of VMS by analysing routinely-collected health records.MethodsWe performed a GWAS of VMS derived from linked primary-care records and cross-sectional self-reported HRT use in up to 153,152 women from UK Biobank, a population-based cohort. In a subset of this cohort (n = 39,356), we analysed exome-sequencing data to test the association with VMS of rare deleterious genetic variants. Finally, we used Mendelian randomisation analysis to investigate the reasons for HRT use over time.ResultsOur GWAS of health-records derived VMS identified a genetic signal near TACR3 associated with a lower risk of VMS (OR=0.76 (95% CI 0.72,0.80) per A allele, P=3.7x10-27), which was consistent with previous studies, validating this approach. Conditional analyses demonstrated independence of genetic signals for puberty timing and VMS at the TACR3 locus, including a rare variant predicted to reduce functional NK3R levels that was associated with later menarche (P = 5 × 10–9) but showed no association with VMS (P = 0.6). Younger menopause age was causally-associated with greater HRT use before 2002 but not after.ConclusionsWe provide support for TACR3 in the genetic basis of VMS but unexpectedly find that rare genomic variants predicted to lower NK3R levels did not modify VMS, despite the proven efficacy of NK3R antagonists. Using genomics we demonstrate changes in genetic associations with HRT use over time, arising from a change in clinical practice since the early 2000s, which is likely to reflect a switch from preventing post-menopausal complications in women with earlier menopause to primarily treating VMS. Our study demonstrates that integrating routinely-collected primary care health records and genomic data offers great potential for exploring the genetic basis of symptoms.

Investigating Incidence of Nausea and Vomiting in Patients Receiving Concurrent Chemoradiotherapy: A Real-World Cohort Study.

Vomiting and nausea (VN) caused by anticancer agents and/or radiation therapy (RT) can significantly affect a patient's quality of life, leading to poor compliance with further anticancer agents and/or RT. Few studies pay attention to synergistic effect of RT and concurrent highly emetogenic chemotherapy for inducing vomiting and nausea. The aim of this real-world study is to investigate the incidence of VN in patients receiving concurrent chemoradiotherapy (CCRT). From June 2022 to December 2022, patients receiving concurrent chemoradiotherapy in our center were consecutively enrolled in this study. Patients received moderate and low emetic agents were excluded. The antiemesis regimens were NK1 receptor antagonist plus 5-HT3 antagonist and dexamethasone (NHD) with or without olanzapine, which were recommended by guideline of National Comprehensive Cancer Network. Acute and delayed VN were analyzed in the following stratification factors: tumor site and antiemesis regimen. Acute VN usually occurred after administration of anticancer agents and commonly resolves within the first 24 hours. Delayed VN develops in patients more than 24 hours after anticancer agent administration. The grade of VN was evaluated according to Common Terminology Criteria for Adverse Events Criteria. A total of 312 patients were enrolled for analysis. During the CCRT period, the incidence rate of acute VN in all patients was 28.2%, the delayed VN occurred in 139 of 312 patients (44.6%). The incidence rate of acute nausea in head and neck, thorax and abdomen were 33.8%, 28.9% and 25.2%, respectively. The incidence rate of acute vomiting in head and neck, thorax and abdomen were 7.0%, 3.9% and 5.2%, respectively. The incidence rate of delayed nausea in head and neck, thorax and abdomen were 51.1%, 35.5% and 45.9%, respectively. The incidence rate of delayed vomiting in head and neck, thorax and abdomen were 14.0%, 5.3% and 9.6%, respectively. There were not significant differences between NHD regimen and NHD plus olanzapine in VN (acute nausea, 25.5% vs. 30.3%, P = 0.356; acute vomiting, 4.4% vs. 6.8%, P = 0.352; delayed nausea, 40.1% vs. 48%, P = 0.166; delayed vomiting, 8.0% vs. 10.8%, P = 0.4). Multivariate logistic regression analysis showed age <50 years (P = 0.030. HR, 95% CI: 1.893, 1.062-3.374) and history of vomiting = 0.017, HR, 95% CI: 2.249, 1.154-4.384) were risk factor for acute nausea; female (P = 0.026, HR, 95% CI: 4.254, 1.192-15.186) and sleeping time <7 hours (p = 0.049, HR, 95% CI: 3.373, 1.003-11.344) were risk factors for acute vomiting; pregnancy (P = 0.011, HR, 95% CI: 2.424, 1.228-4.783) was risk factor for delayed nausea; pregnancy = 0.013, HR, 95% CI: 3.060, 1.269-7.380) and history of vomiting = 0.020, HR, 95% CI: 2.845, 1.182-6.844) were risk factors for delayed vomiting in patients receiving CCRT. CCRT still contributed high incidence of delayed nausea in patients receiving standard antiemesis regimen.

The SP/NK1R system promotes the proliferation of breast cancer cells through NF-κB-mediated inflammatory responses.

Numerous molecules have been introduced to participate in the formation of breast cancer, the most common malignancy in women. Among them, neuropeptide substance P (SP) and its related receptor neurokinin-1 receptor (NK1R) have attracted unprecedented attention in tumorigenesis processes. In this study, we investigated the effect of the SP/NK1R pathway on the induction of oxidative stress in breast cancer and examine the therapeutic potential of NK1R inhibition in this malignancy. MCF-7 cells were treated with varying concentrations of SP and aprepitant, an FDA-approved NK1R antagonist, either as a single drug or in a combined modality. Resazurin assay was used to evaluate the anti-cancer ability of aprepitant. The alteration in the intracellular levels of reactive oxygen species (ROS) and gene expression were determined using ROS assay and the qRT-PCR analysis, respectively. The stimulation of the SP/NK1R axis in the MCF-7 cells was coupled with the accumulation of ROS as well as upregulation of NF-κB and its related pro-inflammatory cytokines, including tumor necrosis factor (TNF)-α and IL-6. In contrast, the suppression of NK1R by aprepitant halted the viability of MCF-7 cells, at least partly due to p53-mediated upregulation of p21. Moreover, aprepitant attenuated the oncogenic properties of SP by preventing the oxidative property of this neuropeptide. Overall, our results suggest that the SP/NK1R pathway might play a critical role in breast cancer pathogenesis, probably through inducing ROS/NF-κB-mediated inflammatory responses. Moreover, it seems that blockage of the axis has promising therapeutic value against breast cancer cells. Schematic representation proposed for the plausible mechanism by which the stimulation of the SP/NK1R might induce oxidative stress in breast cancer-derived MCF-7 cells. Once SP interacts with NK1R, this signaling axis could disturb the balance between the expression of p53 and NF-κB, an event that leads to the accumulation of ROS within MCF-7 cells. The produced ROS, in turn, elevates the expression of pro-inflammatory cytokines (TNF-α and IL-6) and downregulates the expression of p21. On the other hand, aprepitant, an antagonist of NK1R, could reduce the survival of proliferative capacity of MCF-7 cells by decreasing the intracellular levels of ROS and p53-mediated up-regulation of p21. Along with the effect on p53, aprepitant could also reduce the expression of NF-κB and its related pro-inflammatory cytokines.

An assessment of the effects of neurokinin1 receptor antagonism against nausea and vomiting: Relative efficacy, sites of action and lessons for future drug development.

A broad-spectrum anti-vomiting effect of neurokinin1 receptor antagonists (NK1 RA), shown in pre-clinical animal studies, has been supported by a more limited range of clinical studies in different indications. However, this review suggests that compared with vomiting, the self-reported sensation of nausea is less affected or possibly unaffected (depending on the stimulus) by NK1 receptor antagonism, a common finding for anti-emetics. The stimulus-independent effects of NK1 RAs against vomiting are explicable by actions within the central pattern generator (ventral brainstem) and the nucleus tractus solitarius (NTS; dorsal brainstem), with additional effects on vagal afferent activity for certain stimuli (e.g., highly emetogenic chemotherapy). The central pattern generator and NTS neurones are multifunctional so the notable lack of obvious effects of NK1 RAs on other reflexes mediated by the same neurones suggests that their anti-vomiting action is dependent on the activation state of the pathway leading to vomiting. Nausea requires activation of cerebral pathways by projection of information from the NTS. Although NK1 receptors are present in cerebral nuclei implicated in nausea, and imaging studies show very high receptor occupancy at clinically used doses, the variable or limited ability of NK1 RAs to inhibit nausea emphasizes: (i) our inadequate understanding of the mechanisms of nausea; and (ii) that classification of a drug as an anti-emetic may give a false impression of efficacy against nausea vs. vomiting. We discuss the potential mechanisms for the differential efficacy of NK1 RA and the implications for future development of drugs that can effectively treat nausea, an area of unmet clinical need.

Diterpenes of Pinus pinaster aiton with anti-inflammatory, analgesic, and antibacterial activities

Ethno-pharmacological relevanceThe P. pinaster species, known as ‘Pino nigral or rodeno’, is used in the treatment of colds, asthma, flu, and tuberculosis. Aim of the studyThis study determined the anti-inflammatory, analgesic, and antibacterial activities of the P. pinaster resin, identifying the compounds with higher biological activity. Materials and methodsA bio-guided isolation of the compounds of P. pinaster was carried out by selecting the most active extracts with anti-inflammatory and analgesic effects in the HBEC3-KT, MRC-5, and THP-1 cell lines. The antibacterial activity was determined against the S. aureus, S. pneumoniae, K. pneumoniae and P. aeruginosa strains. ResultsThe following compounds were identified by NMR: dehydroabietic acid (1), ( + )-cis-abienol (2), pimaric acid (3), isopimaric acid (4), 7α-hydroxy-dehydroabietic acid (5), 7-oxo-dehydroabietic acid (6), 15-hydroxy-abietic acid (7), 7-oxo-15-hydroxy-dehydroabietic acid (8), 13-oxo-8 (14)-podocarpen-18-oic acid (9), and pinyunin A (10). Regarding their anti-inflammatory activity, all compounds inhibited NF-κB. Compound 9 was the most active (IC50 = 3.90–12.06 μM). Concerning the analgesic activity, all the compounds inhibited NK-1, yet compound 9 was the most active (IC50 = 0.28–0.33 μM). Finally, compounds 6 (MIC = 12.80–25.55 μM) and 9 (MIC = 9.80–24.31 μM) were the most promising antibacterial compounds in all strains. ConclusionThis study managed to identify, for the first time, six diterpenes from the resin of P. pinaster, with anti-inflammatory, analgesic, and antibacterial activity. Among the identified compounds, compound 9 was the most active, being considered a promising candidate as an antagonist of the tachykinin NK-1 receptor and as an analgesic agent against inflammation and neuropathic pain. It also had an antibacterial effect against Gram negative bacteria.

Clinical Guidance on the Monitoring and Management of Trastuzumab Deruxtecan (T-DXd)-Related Adverse Events: Insights from an Asia-Pacific Multidisciplinary Panel.

Trastuzumab deruxtecan (T-DXd)-an antibody-drug conjugate targeting the human epidermal growth factor receptor 2 (HER2)-improved outcomes of patients with HER2-positive and HER2-low metastatic breast cancer. Guidance on monitoring and managing T-DXd-related adverse events (AEs) is an emerging unmet need as translating clinical trial experience into real-world practice may be difficult due to practical and cultural considerations and differences in health care infrastructure. Thus, 13 experts including oncologists, pulmonologists and a radiologist from the Asia-Pacific region gathered to provide recommendations for T-DXd-related AE monitoring and management by using the latest evidence from the DESTINY-Breast trials, our own clinical trial experience and loco-regional health care considerations. While subgroup analysis of Asian (excluding Japanese) versus overall population in the DESTINY-Breast03 uncovered no major differences in the AE profile, we concluded that proactive monitoring and management are essential in maximising the benefits with T-DXd. As interstitial lung disease (ILD)/pneumonitis is a serious AE, patients should undergo regular computed tomography scans, but the frequency may have to account for the median time of ILD/pneumonitis onset and access. Trastuzumab deruxtecan appears to be a highly emetic regimen, and prophylaxis with serotonin receptor antagonists and dexamethasone (with or without neurokinin-1 receptor antagonist) should be considered. Health care professionals should be vigilant for treatable causes of fatigue, and patients should be encouraged to use support groups and practice low-intensity exercises. To increase treatment acceptance, patients should be made aware of alopecia risk prior to starting T-DXd. Detailed monitoring and management recommendations for T-DXd-related AEs are discussed further.

Single-dose NEPA versus an aprepitant regimen for prevention of chemotherapy-induced nausea and vomiting in patients receiving moderately emetogenic chemotherapy.

Non-inferiority of NEPA (fixed combination of NK1 receptor antagonist (RA), netupitant, and 5-HT3 RA, palonosetron) versus an aprepitant regimen was previously shown in a pragmatic study in patients receiving anthracycline cyclophosphamide (AC) and non-AC moderately emetogenic chemotherapy (MEC). In the MEC group a numerically higher complete response (CR: no emesis, no rescue) rate was seen for NEPA during the overall 0-120 h phase (NEPA 76.1% vs. 63.1% aprepitant). As NEPA exhibits long-lasting efficacy, this study evaluated a prolonged period up to 144 h, beyond the traditional 120 h post-chemotherapy. In this post-hoc analysis we explore the comparative efficacy of NEPA versus the aprepitant regimen in the MEC group up to 144 h, while also assessing the impact of risk factors on CINV prevention. This was a pragmatic, multicenter, randomized, prospective study. Oral NEPA was administered as a single dose on day 1, while aprepitant was given on days 1-3 + ondansetron on day 1; all patients were to receive dexamethasone on days 1-4. Patients were chemotherapy-naïve and receiving MEC, with a subset evaluation of those with a risk factor for developing CINV (i.e., female, male <60 years, male ≥60 years who received carboplatin, or male ≥60 years with anxiety). CR rates were compared during the extended overall (0-144 h) phase. The MEC group included 211 patients; of these 181 were in the risk factor subset. Significantly higher CR rates were seen for NEPA than aprepitant during the extended overall phase for the total MEC group (NEPA 77.1%, aprepitant 57.8%, p = 0.003) and also in the subset of patients with CINV risk factors (NEPA 73.9%, aprepitant 56.2%, p = 0.012). A single dose of NEPA, administered on day 1 only, was more effective than a 3-day aprepitant regimen in preventing CINV for an extended duration in patients receiving MEC and in those with emetic risk factors.

Possibilities of prevention of nausea during cytostatic therapy: literature review and clinical cases

Chemotherapy-induced nausea and vomiting (CINV) is a side effect of cancer treatment, affecting up to 40% of patients. Nausea and vomiting are the most dangerous and also the most common side effects among patients undergoing chemotherapy. CINV remains one of the most worrisome syndromes associated with cancer therapy and can lead to dehydration, electrolyte imbalances, malnutrition, and metabolic disorders. Risk factors for developing CINV include the patient’s gender and age, a history of CINV, and the emetogenicity and timing of chemotherapy. Options for preventing CINV are 5-HT3 receptor antagonists (i.e., ondansetron, granisetron, palonosetron) in combination with corticosteroids (i.e., dexamethasone) or additionally in combination with NK1 receptor antagonists (i.e., aprepitant, fosaprepitant, netupitant, rolapitant). Palonosetron is a selective 5-hydroxytryptamine 3 (5-HT3) receptor antagonist. The effectiveness of palonosetron for delayed nausea and vomiting is also supported by the results of three randomized trials that demonstrated no side effects of the simplified regimen with palonosetron and single dose dexamethasone for the control of CINV associated with moderately emetogenic chemotherapy or AC regimen. A clinical observation of the treatment of a young patient with breast cancer is given. After the first course of chemotherapy, the patient developed a rather serious complication in the form of vomiting, which required hospitalization for infusion therapy. The above clinical observation demonstrates the effectiveness of palonosetron in neo-adjuvant chemotherapy in a young patient, which made it possible to complete the entire course of treatment. After completion of neo-adjuvant chemotherapy, a radical operation was performed and a complete morphological response was noted.

Effect of GR205171 on autonomic dysreflexia induced by colorectal distension in spinal cord injured rats.

Preclinical pharmacology. To determine whether blocking substance P signaling attenuates the hypertension and bradycardia evoked by colorectal distension (CRD) in spinal cord injured (SCI) rats. University laboratory in Pennsylvania, U.S.A. Tachykinin NK1 receptor antagonists were administered 30 min prior to CRD three weeks after complete spinal cord transection at the 4th thoracic (T4) level. The dose range, route of administration, and pretreatment time was based on published data demonstrating occupancy of brain NK1 receptors in rodents. Subcutaneous (SC) administration of 10-30 mg/kg GR205171 ((2S,3S)-N-[[2-methoxy-5-[5-(trifluoromethyl)tetrazol-1-yl]phenyl]methyl]-2-phenylpiperidin-3-amine dihydrochloride) reduced CRD-induced hypertension and bradycardia by 55 and 49%, respectively, compared with pretreatment values. There was no effect of GR205171 on resting blood pressure or heart rate. In contrast, the same dose range of CP-99,994 ((2S,3S)-N-[(2-methoxyphenyl)methyl]-2-phenyl-3-piperidinamine dihydrochloride) had no effect on CRD-induced cardiovascular responses. The effective dose range of GR205171 to alleviate autonomic dysreflexia is consistent with the blockade of NK1 receptors on pelvic sensory afferents in the lumbosacral spinal cord, which may in turn prevent the over-excitation of sympathetic preganglionic neurons (SPNs) that regulate blood pressure and heart rate. The findings provide preclinical support for the utility of NK1 receptor antagonists to treat autonomic dysreflexia in people with SCI. The difference in the effects of the two NK1 receptor antagonists may reflect the ~200-fold lower affinity of CP-99,994 than GR205171 for the rat NK1 receptor.

Fosaprepitant for postoperative nausea and vomiting in patients undergoing laparoscopic gastrointestinal surgery: a randomised trial

BackgroundPostoperative nausea and vomiting (PONV) is a major problem after surgery. Even with double prophylactic therapy including dexamethasone and a 5-hydroxytryptamine-3 receptor antagonist, the incidence is still high in many at-risk patients. Fosaprepitant, a neurokinin-1 receptor antagonist, is an effective antiemetic, but its efficacy and safety in combination antiemetic therapy for preventing PONV remain unclear. MethodsIn this randomised, controlled, double-blind trial, 1154 participants at high risk of PONV and undergoing laparoscopic gastrointestinal surgery were randomly assigned to either a fosaprepitant group (n=577) receiving fosaprepitant 150 mg i.v. dissolved in 0.9% saline 150 ml, or a placebo group (n=577) receiving 0.9% saline 150 ml before anaesthesia induction. Dexamethasone 5 mg i.v. and palonosetron 0.075 i.v. mg were each administered in both groups. The primary outcome was the incidence of PONV (defined as nausea, retching, or vomiting) during the first 24 postoperative hours. ResultsThe incidence of PONV during the first 24 postoperative hours was lower in the fosaprepitant group (32.4% vs 48.7%; adjusted risk difference −16.9% [95% confidence interval: −22.4 to −11.4%]; adjusted risk ratio 0.65 [95% CI: 0.57 to 0.76]; P<0.001). There were no differences in severe adverse events between groups, but the incidence of intraoperative hypotension was higher (38.0% vs 31.7%, P=0.026) and intraoperative hypertension (40.6% vs 49.2%, P=0.003) was lower in the fosaprepitant group. ConclusionsFosaprepitant added to dexamethasone and palonosetron reduced the incidence of PONV in patients at high risk of PONV undergoing laparoscopic gastrointestinal surgery. Notably, it increased the incidence of intraoperative hypotension. Clinical trial registrationNCT04853147.

Prolonged usage of fosaprepitant for prevention of delayed chemotherapy-induced nausea and vomiting(CINV) in patients receiving highly emetogenic chemotherapy

BackgroundEven though chemotherapy-induced nausea and vomiting (CINV) can be well controlled in the acute phase, the incidence of delayed CINV remains high. In this study, we intend to investigate whether prolonged use of NK-1 receptor antagonist (RA) in addition to 5-HT3 RA and dexamethasone (DEX) was more effective in preventing delayed CINV.MethodsThis randomised, open-label, controlled study was designed to compare the efficacy and safety of fosaprepitant 150 mg given on days 1,3 (prolonged group) versus on day 1 (regular group) in patients receiving highly emetogenic chemotherapy (HEC). All patients also treated with palonosetron on day 1 and DEX on days 1–3. The primary endpoint was the incidence of delayed nausea and vomiting. The second endpoint was AEs. All the above endpoints were defined according to CTCAE 5.0.ResultsSeventy-seven patients were randomly assigned to prolonged group and seventy-nine to regular group. Prolonged group demonstrated superiority in controlling delayed CINV to regular group, with statistically significant lower incidence of nausea (6.17% vs 12.66%, P = 0.0056), and slightly lower incidence of grade 1 vomiting (1.62% vs 3.80%, P = 0.0953) in the delayed phase. In addition, prolonged use of fosaprepitant was safe. No significant difference was found between the two groups regarding constipation, diarrhea, hiccough, fatigue, palpitation and headache in delayed phase.ConclusionsProlonged use of fosaprepitant can effectively and safely prevent delayed CINV in patients receiving HEC.

Regional characterisation of TRPV1 and TRPA1 signalling in the mouse colon mucosa

Capsaicin and allyl isothiocyanate (AITC) activate transient receptor potential (TRP) vanilloid-1 (TRPV1) and TRP ankyrin-1 (TRPA1), respectively. TRPV1 and TRPA1 expression have been identified in the gastrointestinal (GI) tract. GI mucosal functions remain largely undefined for TRPV1 and TRPA1 with side-dependence and regional differences in signalling unclear. Here we investigated TRPV1- and TRPA1-induced vectorial ion transport as changes in short-circuit current (ΔIsc), in defined segments of mouse colon mucosa (ascending, transverse and descending) under voltage-clamp conditions in Ussing chambers. Drugs were applied basolaterally (bl) or apically (ap). Capsaicin responses were biphasic, with primary secretory and secondary anti-secretory phases, observed with bl application only, which predominated in descending colon. AITC responses were monophasic and secretory, with ΔIsc dependent on colonic region (ascending vs. descending) and sidedness (bl vs. ap). Aprepitant (neurokinin-1 (NK1) antagonist, bl) and tetrodotoxin (Na+ channel blocker, bl) significantly inhibited capsaicin primary responses in descending colon, while GW627368 (EP4 receptor antagonist, bl) and piroxicam (cyclooxygenase inhibitor, bl) inhibited AITC responses in ascending and descending colonic mucosae. Antagonism of the calcitonin gene-related peptide (CGRP) receptor had no effect on mucosal TRPV1 signalling, while tetrodotoxin and antagonists of the 5-hydroxytryptamine-3 and 4 receptors, CGRP receptor, and EP1/2/3 receptors had no effect on mucosal TRPA1 signalling. Our data demonstrates the regional-specificity and side-dependence of colonic TRPV1 and TRPA1 signalling, with involvement of submucosal neurons and mediation by epithelial NK1 receptor activation for TRPV1, and endogenous prostaglandins and EP4 receptor activation for TRPA1 mucosal responses.

Systematized review of the literature on postoperative nausea and vomiting

Introduction: Postoperative nausea and vomiting (PONV) is the most common adverse effect, after postoperative pain, with an incidence of 31.1% to 80%, which increases pain, favors broncho aspiration, wound dehiscence, and hematoma formation. Methodology: Systematized search keywords, postoperative nausea and vomiting, Incidence, therapeutics, Apfel score and risk score for postoperative nausea and vomiting, in PubMed database, the Cochrane central register of controlled trials and in http://www.clinicaltrials.gov. Results: A total of 2750 articles were obtained, and 62 articles were chosen for inclusion. Discussion: The drugs used as monotherapy to mitigate PONV such as palonosetron, fosaprepitant and aprepitant, show better results than the rest of the drugs. Conclusion: Currently, NK1 receptor antagonist drugs and 5-HT3 antagonists have been shown to have the best results in preventing PONV, however, the management of PONV should be multimodal and individualized.

Nausea and vomiting induced by pharmacotherapy: have all issues of maintenance therapy been resolved?

Many patients with various localizations of malignant neoplasms require therapy aimed at preventing or reducing the manifestations of nausea and vomiting induced by anticancer pharmacotherapy. New drugs to prevent the development of complications of chemotherapy are critical to improve the quality of life of patients and their adherence to therapy. Palonosetron, a new generation 5-HT3 receptor antagonist, has a long half-life (up to 40 hours) and a 30-fold higher affinity for 5-HT3 receptors compared to previous generations of 5-HT3 receptor antagonists. Clinical studies have shown the ability of palonosetron in combination with dexamethasone and, if indicated, neurokinin antagonists to effectively prevent the development of nausea and vomiting during single- and multi-day cycles of chemotherapy for both solid tumors and hematological diseases, including high-dose chemotherapy, in preparation for transplantation of auto- and allogeneic stem cells. The innovative oral drug Akynzeo is currently available for use in clinical practice, which includes 2 highly selective NK1 and 5-HT3 receptor antagonists in fixed doses. The drug prevents induced nausea and vomiting during moderate and highly emetogenic chemotherapy in more than 90 % of cases, both in the acute and delayed phases.

Brain nanotargeted [131I] I-Rolapitant as a model for brain imaging: Intranasal formulation, radiolabelling, biodistribution, and comparative study

The goal of this study was to create a novel single-photon emission computed tomography (SPECT) probe that would enable the visualization of neurokinin-1 NK1 receptor systems in the brain for the precise diagnosis and follow-up of many brain-related disorders. Rolapitant (RT), a selective, high-affinity NK1 receptor antagonist, was successfully radiolabelled with the radioactive Iodine 131I with high radiolabelling efficiency after refining several parameters impacting the radiolabelling process' efficiency. To improve the radiopharmaceutical's bioavailability, and brain delivery and boost the diagnostic yield of the novel radiopharmaceutical formulation, [131I] I-Rolapitant was successfully fabricated in a spanlastic nanovesicle (SNV) formulation with a convenient hydrodynamic size, a reasonable biocompatibility profile, and feasible in vitro stability. The selected formula was evaluated comparatively in a parallel biodistribution study in contrast to RT intravenous and intranasal solutions comparing brain targeting efficiency. The in vivo study revealed a high brain uptake (6.740 ± 0.09% ID/g) 2 h post-administration which was 3fold greater than the brain uptake of [131I] I-Rolapitant intravenous solution. Regarding the Brain/Blood Ratio, [131I] I-Rolapitant SNV outperformed RT intravenous and intranasal solutions, with a maximum ratio of 2.03 reached 24 h after administration. These results suggest that the proposed spanlastic nanoform could be regarded as a promising drug vector for the transnasal delivery of radiopharmaceuticals to the brain.

Neurokinin-1 receptor antagonists for the prevention of postoperative nausea and vomiting.

Despite the availability of several classes of antiemetics, postoperative nausea and vomiting (PONV) remains a substantial burden for patients following surgery, resulting in patient dissatisfaction and prolonged stays in post-anesthesia care units and ultimately increasing the cost of care. Enhanced recovery protocols and PONV management guidelines are now centered on the assessment of the individual patient's risk for developing PONV, as well as multimodal prophylaxis using antiemetics targeting different mechanisms of action. Over the last two decades, the neurokinin-1 receptor (NK1R) has emerged as a therapeutic target for the management of PONV. This review of the literature explains the role of the NK1R and its ligand-substance P-in vomiting, describes the pharmacologic and pharmacokinetic properties of NK1R antagonists (NK1RAs) and summarizes the clinical evidence supporting NK1RAs for PONV prophylaxis in patients undergoing surgery. In particular, we discuss the therapeutic application of NK1RA in PONV prophylaxis protocols owing to their advantages over other antiemetic classes in efficacy, duration of efficacy, safety, pharmacology, and ease of administration. Future studies will be aimed at further investigating the efficacy and safety of NK1RA-based multimodal combinations, particularly among vulnerable populations (e.g., children and elderly).

Current Management of CINV

Chemotherapy-induced nausea and vomiting (CINV) prevention is important to reduce overall morbidity and financial burden in patients receiving chemotherapy. Severe symptoms reduce the patient's quality of life and can interfere with further treatment. The five major forms of CINV (ie, acute, delayed, predicted, breakthrough, and refractory) often include 5-HT3 receptor antagonists, NK1 receptor antagonists, and various treatments that often include corticosteroids. Despite significant research and development efforts on antiemetics, treatment of CINV remains a major challenge, waiting for many needs to be adequately addressed, including those that are vulnerable to CINV despite adequately treated. This review hope to raise awareness and discuss current current CINV management.