A transcriptomic taxonomy of mouse brain-wide spinal projecting neurons.

The brain controls nearly all bodily functions via spinal projecting neurons (SPNs) that carry command signals from the brain to the spinal cord. However, a comprehensive molecular characterization of brain-wide SPNs is still lacking. Here we transcriptionally profiled a total of 65,002 SPNs, identified 76 region-specific SPN types, and mapped these types into a companion atlas of the whole mouse brain1. This taxonomy reveals a three-component organization of SPNs: (1) molecularly homogeneous excitatory SPNs from the cortex, red nucleus and cerebellum with somatotopic spinal terminations suitable for point-to-point communication; (2) heterogeneous populations in the reticular formation with broad spinal termination patterns, suitable for relaying commands related to the activities of the entire spinal cord; and (3) modulatory neurons expressing slow-acting neurotransmitters and/or neuropeptides in the hypothalamus, midbrain and reticular formation for 'gain setting' of brain-spinal signals. In addition, this atlas revealed a LIM homeobox transcription factor code that parcellates the reticulospinal neurons into five molecularly distinct and spatially segregated populations. Finally, we found transcriptional signatures of a subset of SPNs with large soma size and correlated these with fast-firing electrophysiological properties. Together, this study establishes a comprehensive taxonomy of brain-wide SPNs and provides insight into the functional organization of SPNs in mediating brain control of bodily functions.

Corrigendum: Efficacy and Safety of Shenqu Xiaoshi Oral Liquid Compared With Domperidone Syrup in Children With Functional Dyspepsia.

[This corrects the article DOI: 10.3389/fphar.2022.831912.].

Efficacy and Safety of Shenqu Xiaoshi Oral Liquid Compared With Domperidone Syrup in Children With Functional Dyspepsia.

Background: Treatment of functional dyspepsia (FD) in children is generally symptomatic and unsatisfactory. Traditional Chinese medicines, such as Shenqu Xiaoshi Oral Liquid (SXOL), have been recommended to alleviate dyspeptic symptoms. However, evidence of their safety and efficacy remains limited to date. AIM: To assess whether 2 weeks of therapy with SXOL was non-inferior to domperidone syrup in children with FD. Methods: In this randomized, double-blind, double-simulated, non-inferiority, multi-center clinical trial, we recruited children (3-14 years) with FD according to the Rome IV criteria from 17 tertiary medical centers across China. Patients were randomly allocated (1:1) to receive SXOL or domperidone syrup for 2 weeks. We compared the participants' clinical scores from both groups based on the severity and frequency of dyspepsia symptoms according to Rome IV criteria (0, 1, 2, and 4 weeks after randomization). The primary endpoint was the total response rate, which was defined as the proportion of patients with a decrease of 30% or more in the FD symptoms clinical score from baseline, at the end of the 2-weeks treatment. A non-inferiority margin of -10% was set. Secondary endpoints and adverse events were assessed. This trial is registered with www.Chictr.org.cn, number ChiCTR1900022654. Results: Between February 2019 and March 2021, a total of 373 patients were assessed for eligibility, and 356 patients were enrolled and randomized. The clinical response rate at week two was similar for SXOL [118 (83.10%) of 142] and domperidone [128 (81.01%) of 158]; difference 2.09; 95% CI -6.74 to 10.71, thereby establishing non-inferiority. The total FD symptom scores were significantly improved in the two groups at 1-, 2-, and 4-weeks follow-up periods (p < 0.005). The decrease in symptom score compared with the baseline were similar between these two groups. Over the total study period, 10 patients experienced at least one treatment-related adverse event [six (3.37%)] in the SXOL group, four [(2.25%) in the domperidone group], although no serious adverse event was noted. Conclusion: Treatment with SXOL effectively improves dyspeptic symptoms and is well tolerated. In addition, it is not inferior to domperidone syrup and leads to sustained improvement in Chinese children with FD.

Preclinical insights into therapeutic targeting of KCC2 for disorders of neuronal hyperexcitability.

INTRODUCTION: Epilepsy is a common neurological disorder of neuronal hyperexcitability that begets recurrent and unprovoked seizures. The lack of a truly satisfactory pharmacotherapy for epilepsy highlights the clinical urgency for the discovery of new drug targets. To that end, targeting the electroneutral K+/Cl- cotransporter KCC2 has emerged as a novel therapeutic strategy for the treatment of epilepsy. AREAS COVERED: We summarize the roles of KCC2 in the maintenance of synaptic inhibition and the evidence linking KCC2 dysfunction to epileptogenesis. We also discuss preclinical proof-of-principle studies that demonstrate that augmentation of KCC2 function can reduce seizure activity. Moreover, potential strategies to modulate KCC2 activity for therapeutic benefit are highlighted. EXPERT OPINION: Although KCC2 is a promising drug target, questions remain before clinical translation. It is unclear whether increasing KCC2 activity can reverse epileptogenesis, the ultimate curative goal for epilepsy therapy that extends beyond seizure reduction. Furthermore, the potential adverse effects associated with increased KCC2 function have not been studied. Continued investigations into the neurobiology of KCC2 will help to translate promising preclinical insights into viable therapeutic avenues that leverage fundamental properties of KCC2 to treat medically intractable epilepsy and other disorders of failed synaptic inhibition with attendant neuronal hyperexcitability.

Changes in Cold and Hot Syndrome and Gastrointestinal Bacterial Community Structure in Mice by Intervention with Food of Different Nature.

OBJECTIVE: To reveal the effect of foods with different natures on cold or hot syndrome and gastrointestinal bacterial community structure in mice. METHODS: Forty-five 6-week-old male ICR Kunming mice of clean grade were divided into 5 groups, 9 per group, including the control (CK), hot nature herbs (HM), Hong Qu glutinous rice wine (RW), tea rice wine (TW), and cold nature herbs (CM) groups. Distilled water or corresponding herbs were administered to mice (0.01 mL/g body weight) in the 5 groups by gastric infusion respectively, once daily for 28 d. Appearance, behavior, and serum biochemical indicators, including 5-hydroxytryptamine (5-HT), thyroid stimulating hormone (TSH), noradrenaline (NE), cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), the hot nature index, as well as the gastrointestinal bacterial community structure were analyzed in all groups after treatment. RESULTS: After supplementation for 28 d, CM and TW mice showed different degrees of cold syndrome, and HM and RW mice showed different degrees of hot syndrome. Compared with the HM and RW mice, the TSH, NE, cAMP levels and hot nature indices in the CM and TW mice were significantly decreased and 5-HT and cGMP levels were significantly increased (P<0.05). There was no obvious change in appearance or behavior in CK mice. Results of clustering analysis showed that the gastrointestinal bacterial community structures were highly similar in TW and CM mice as well as in RW and HM mice, and that they were from the same branch, respectively, when the distance was 0.02. The key microbes associated with cold syndrome were Lachnospiraceae uncultured, Lactococcus, etc., and the key microbes associated with hot syndrome were S24-7 norank, Ruminococcaceae uncultured, etc. CONCLUSION: The interventions with different nature foods could change cold or hot syndrome in mice, leading to changes in gastrointestinal bacterial community structure.

Influence of a Decaying Cyclonic Eddy on Biogenic Silica and Particulate Organic Carbon in the Tropical South China Sea Based on 234Th-238U Disequilibrium.

Eddies play a critical role in regulating the biological pump by pumping new nutrients to the euphotic zone. However, the effects of cyclonic eddies on particle export are not well understood. Here, biogenic silica (BSi) and particulate organic carbon (POC) exports were examined inside and outside a decaying cyclonic eddy using 234Th-238U disequilibria in the tropical South China Sea. For the eddy and outside stations, the average concentrations of BSi in the euphotic zone were 0.17±0.09 µmol L-1 (mean±sd, n = 20) and 0.21±0.06 µmol L-1 (n = 34). The POC concentrations were 1.42±0.56 µmol L-1 (n = 34) and 1.30±0.46 µmol L-1 (n = 51). Both BSi and POC abundances did not show change at the 95% confidence level. Based on the 234Th-238U model, BSi export fluxes in the eddy averaged 0.18±0.15 mmol Si m-2 d-1, which was comparable with the 0.40±0.20 mmol Si m-2 d-1 outside the eddy. Similarly, the average POC export fluxes were 1.5±1.4 mmol C m-2 d-1 and 1.9±1.3 mmol C m-2 d-1 for the eddy and outside stations. From these results we concluded that cyclonic eddies in their decaying phase have little effect on the abundance and export of biogenic particles.

A selective Sema3A inhibitor enhances regenerative responses and functional recovery of the injured spinal cord.

Axons in the adult mammalian central nervous system (CNS) exhibit little regeneration after injury. It has been suggested that several axonal growth inhibitors prevent CNS axonal regeneration. Recent research has demonstrated that semaphorin3A (Sema3A) is one of the major inhibitors of axonal regeneration. We identified a strong and selective inhibitor of Sema3A, SM-216289, from the fermentation broth of a fungal strain. To examine the effect of SM-216289 in vivo, we transected the spinal cord of adult rats and administered SM-216289 into the lesion site for 4 weeks. Rats treated with SM-216289 showed substantially enhanced regeneration and/or preservation of injured axons, robust Schwann cell-mediated myelination and axonal regeneration in the lesion site, appreciable decreases in apoptotic cell number and marked enhancement of angiogenesis, resulting in considerably better functional recovery. Thus, Sema3A is essential for the inhibition of axonal regeneration and other regenerative responses after spinal cord injury (SCI). These results support the possibility of using Sema3A inhibitors in the treatment of human SCI.