Survival in animals relies on navigating environments aligned with physiological needs. In Drosophila melanogaster, antennal ionotropic receptors (IRs) sensing humidity changes govern hygrotaxis behavior. This study sheds light on the crucial role of IR8a neurons in the transition from high humidity avoidance to water-seeking behavior when the flies become thirsty. These neurons demonstrate a heightened calcium response toward high humidity stimuli in satiated flies and a reduced response in thirsty flies, modulated by fluctuating levels of the neuropeptide leucokinin, which monitors the internal water balance. Optogenetic activation of IR8a neurons in thirsty flies triggers an avoidance response similar to the moisture aversion in adequately hydrated flies. Furthermore, our study identifies IR40a neurons as associated with dry avoidance, while IR68a neurons are linked to moist attraction. The dynamic interplay among these neurons, each with opposing valences, establishes a preference for approximately 30% relative humidity in well-hydrated flies and facilitates water-seeking behavior in thirsty individuals. This research unveils the intricate interplay between sensory perception, neuronal plasticity, and internal states, providing valuable insights into the adaptive mechanisms governing hygrotaxis in Drosophila.

UNASSIGNED: The skin is an intricate network of both neurons and immunocytes, where emerging evidence has indicated that the regulation of neural-inflammatory processes may play a crucial role in mediating wound healing. Disease associated abnormal immunological dysfunction and peripheral neuropathy are implicated in the pathogenesis of wound healing impairment. However, the mechanisms through which neural-inflammatory interactions modulate wound healing remain ambiguous. Understanding the underlying mechanisms may provide novel insights to develop therapeutic devices, which could manipulate neural-inflammatory crosstalk to aid wound healing. This review aims to comprehensively illustrate the neural-inflammatory interactions during different stages of the repair process. Numerous mediators including neuropeptides secreted by the sensory and autonomic nerve fibers and cytokines produced by immunocytes play an essential part during the distinct phases of wound healing.

Type II crustacean hyperglycemic hormone (CHH) neuropeptides play diverse roles in crustaceans. In the hermaphrodite shrimp Lysmata vittata, two transcripts of type II CHHs (molt-inhibiting hormone/gonad-inhibiting hormone, MIH/GIH1 and MIH/GIH2) were identified by transcriptome sequencing, and MIH/GIH1 was later named Lvit-GIH1 for its inhibitory effect on ovarian development. Based on the high similarity of MIH/GIH2 to Lvit-GIH1, we named tentatively MIH/GIH2 as Lvit-GIH2 and explored the role of Lvit-GIH2 in ovarian development. The open reading frame (ORF) of Lvit-GIH2 was 333 bp in length, encoding a precursor consisted of a 32-aa signal peptide and a 78-aa mature peptide, which shared high sequence similarity with the type II subfamily peptides in crustaceans. Notably, Lvit-GIH2 was widely expressed in multiple tissues. The qRT-PCR findings indicated a rising trend in the expression of Lvit-GIH2 from the male phase to the euhermaphrodite phase. Both RNA interference and addition of GIH2 recombinant proteins (rGIH2) experiments showed that Lvit-GIH2 suppressed Lvit-Vg expression in hepatopancreas and Lvit-VgR expression in ovary. To further investigate the role of Lvit-GIH2 in ovarian development, the RNA-sequence analysis was performed to examine the changes in ovary after addition of rGIH2. The results showed that the pathways (Cysteine and methionine metabolism, Apoptosis-multiple species, etc.) and the genes (17bHSD8, IGFR, CHH, etc.) related to ovarian development were negatively regulated by rGIH2. In brief, Lvit-GIH2 might inhibit the ovarian development in L. vittata.

Amyloid-β (Aβ) aggregates are recognized as initiators of Alzheimer\'s disease, and their interaction with the nervous system contributes to the progression of neurodegeneration. Herein, we investigated the frequency at which neuropeptides interact with Aβ and affect the aggregation kinetics and cytotoxicity of Aβ. To this end, we established a native mass spectrometry (MS)-centric workflow for screening Aβ-interacting neuropeptides, and six out of 12 neuropeptides formed noncovalent complexes with Aβ species in the MS gas phase. Thioflavin-T fluorescence assays and gel separation indicated that leptin and cerebellin decreased Aβ aggregation, whereas kisspeptin increased this process. In addition, leptin and cerebellin attenuated Aβ-induced cytotoxicity, which was independent of the influence of metal ions. Leptin can chelate copper from copper-bound Aβ species, reducing the cytotoxicity caused by the aggregation of Aβ and metal ion complexes. Overall, our study demonstrated that neuropeptides frequently interact with Aβ and revealed that leptin and cerebellin are potential inhibitors of Aβ aggregation, providing great insight into understanding the molecular mechanism of Aβ interacting with the nervous system and facilitating drug development.

Neuritin plays an important role in promoting nerve injury repair and maintaining synaptic plasticity, making it a potential therapeutic target for the treatment of nerve injury and neurodegenerative diseases. The present study aimed to obtain an active, unlabeled neuritin protein. Initially, a neuritin protein expression system with an enterokinase site was constructed in Escherichia coli. After optimizing induction conditions and screening for high expression, a neuritin recombinant protein with purity exceeding 85 % was obtained through Ni-affinity chromatography. Subsequently, unlabeled neuritin with a molecular weight of 11 kDa was obtained through the enzymatic cleavage of the His label using an enterokinase. Furthermore, a neuritin recombinant protein with purity exceeding 95 % was obtained using gel chromatography. Functional investigations revealed that neurite outgrowth of PC12 cells was stimulated by the isolated neuritin. This study establishes a method to obtain active and unlabeled neuritin protein, providing a foundation for subsequent research on its biological functions.

OBJECTIVE: Secretoneurin may play a brain-protective role. We aim to discover the relationship between serum secretoneurin levels and severity plus neurological outcome after intracerebral hemorrhage (ICH).
METHODS: In this prospective cohort study, serum secretoneurin levels were measured in 110 ICH patients and 110 healthy controls. Glasgow Coma Scale (GCS) and hematoma volume were used to assess stroke severity. Poor prognosis was defined as Glasgow Outcome Scale (GOS) scores of 1-3 at 90 days after ICH. A multivariate logistic regression model was constructed to determine independent correlation of serum secretoneurin levels with severity and poor prognosis. Under receiver operating characteristic (ROC) curve, prognostic ability of serum secretoneurin levels was assessed. Restricted cubic spline (RCS) model and subgroups analysis were used for discovering association of serum secretoneurin levels with risk of poor prognosis. Calibration curve and decision curve were evaluated to confirm performance of nomogram.
RESULTS: Serum secretoneurin levels of patients were significantly higher than those of healthy controls. Serum secretoneurin levels of patients were independently correlated with GCS scores and hematoma volume. There were 42 patients with poor prognosis at 90 days following ICH. Serum secretoneurin levels were significantly higher in patients with poor outcome than in those with good outcome. Under the ROC curve, serum secretoneurin levels significantly differentiated poor outcome. Serum secretoneurin levels ≥ 22.8 ng/mL distinguished patients at risk of poor prognosis at 90 days with a sensitivity of 66.2% and a specificity of 81.0%. Besides, serum secretoneurin levels independently predicted a 90-day poor prognosis. Subgroup analysis showed that serum secretoneurin levels had non-significant interactions with other variables. The nomogram, including independent prognostic predictors, showed reliable prognosis capability using calibration curve and decision curve. Area under the curve of the predictive model was significantly higher than those of GCS scores and hematoma volume.
CONCLUSIONS: Serum secretoneurin levels are strongly related to ICH severity and poor prognosis at 90 days after ICH. Thus, serum secretoneurin may be a promising prognostic biomarker in ICH.

Neuropeptides are biomolecules with crucial physiological functions. Accurate identification of neuropeptides is essential for understanding nervous system regulatory mechanisms. However, traditional analysis methods are expensive and laborious, and the development of effective machine learning models continues to be a subject of current research. Hence, in this research, we constructed an SVM-based machine learning neuropeptide predictor, iNP_ESM, by integrating protein language models Evolutionary Scale Modeling (ESM) and Unified Representation (UniRep) for the first time. Our model utilized feature fusion and feature selection strategies to improve prediction accuracy during optimization. In addition, we validated the effectiveness of the optimization strategy with UMAP (Uniform Manifold Approximation and Projection) visualization. iNP_ESM outperforms existing models on a variety of machine learning evaluation metrics, with an accuracy of up to 0.937 in cross-validation and 0.928 in independent testing, demonstrating optimal neuropeptide recognition capabilities. We anticipate improved neuropeptide data in the future, and we believe that the iNP_ESM model will have broader applications in the research and clinical treatment of neurological diseases.

OBJECTIVE: To observe the clinical effect and safety of the warm acupuncture of Mongolian medicine in treatment of insomnia in the elderly, and to explore its underlying brain-gut peptide mechanism.
METHODS: Sixty elderly patients with insomnia were randomly divided into a warm acupuncture group and a western medication group, 30 cases in each group. In the warm acupuncture group, the warm acupuncture of Mongolian medicine was operated at Dinghuixue (at the center of the vertex, the crossing site of the anterior midline and the line connected the upper edges of two ear apexes), Heyixue (at the depression of the spinous process of the 7th cervical vertebra) or Xinxue (at the depression of the spinous process of the 6th thoracic vertebra) in each treatment. Only one of the above points was selected and stimulated for 20 min one treatment and the three points were used alternatively. The treatment was given once every day or every other day, 3 times a week, and for a total of 3 weeks. In the western medication group, estazolam tablets were administered orally, once a day, 1 mg before bedtime, consecutively for 3 weeks. Before and after treatment, as well as in 1-month follow-up visit after the treatment completion, the scores of the Pittsburgh sleep quality index (PSQI) and the insomnia severity index (ISI) were observed in the two groups. The serum brain-related peptide markers (substance P [SP], neuropeptide Y [NPY], 5-hydroxytryptamine 1A [5-HT1A] and 5-hydroxytryptamine 2A [5-HT2A]) were measured before and after treatment, and the clinical efficacy and safety was evaluated in the two groups.
RESULTS: After treatment and in follow-up, the scores of sleep quality, sleep latency, sleep duration, sleep efficiency, sleep disturbance and daytime dysfunction, as well as the total scores of PSQI, and ISI scores were all reduced in the two groups (P<0.05, P<0.01); and the scores in the warm acupuncture group were lower than those of the western medication group (P<0.05, P<0.01). After treatment, the levels of serum SP and 5-HT2A were decreased (P<0.01) and the levels of serum NPY and 5-HT1A were increased (P<0.01) when compared with those before treatment in the two groups. The levels of serum SP and 5-HT2A in the warm acupuncture group were lower than those of the western medication group (P<0.05), and the levels of serum NPY and 5-HT1A were higher than those of the western medication group (P<0.05). After treatment, the total effective rate was 93.3% (28/30) in the warm acupuncture group, which was higher than 83.3% (25/30) of the western medication group (P<0.05). No serious adverse reactions were found in the two groups.
CONCLUSIONS: Warm acupuncture of Mongolian medicine can effectively improve the sleep quality of the elderly patients with insomnia, and its mechanism may be related to the regulation of the levels of serum SP, NPY, 5-HT1A and 5-HT2A.
目的：观察蒙医温针治疗老年失眠症的临床疗效及安全性，并探究其脑肠肽机制。方法：将60例老年失眠症患者随机分为温针组和西药组，各30例。温针组采用蒙医温针治疗，穴取顶会穴（头顶正中，前正中线与两耳尖上缘连线交叉处）、赫依穴（第7颈椎棘突下凹陷正中）、心穴（第6胸椎棘突下凹陷正中），每次只取1个穴位，3个穴位循环交替使用，每次行蒙医温针20 min，每隔1~2 d治疗1次，每周3次，共治疗3周。西药组给予艾司唑仑片，每日1次，睡前口服1 mg，连续服用3周。于治疗前后及治疗结束后1个月随访时观察两组患者匹兹堡睡眠质量指数（PSQI）、失眠严重程度指数（ISI）评分，比较两组患者治疗前后血清脑肠肽相关指标[P物质（SP）、神经肽（NPY）及5-羟色胺1A（5-HT1A）、5-羟色胺2A（5-HT2A）]水平，并评定两组临床疗效及安全性。结果：治疗后及随访时，两组患者PSQI睡眠质量、入睡时间、睡眠时间、睡眠效率、睡眠障碍、日间功能障碍评分及总分与ISI评分均降低（P<0.05，P<0.01），且温针组均低于西药组（P<0.05，P<0.01）。治疗后，两组患者血清SP、5-HT2A含量较治疗前降低（P<0.01），血清NPY、5-HT1A含量较治疗前升高（P<0.01）；温针组患者血清SP、5-HT2A含量低于西药组（P<0.05），血清NPY、5-HT1A含量高于西药组（P<0.05）。治疗后，温针组患者总有效率为93.3%（28/30），高于西药组的83.3%（25/30，P<0.05），两组均未出现严重不良反应。结论：蒙医温针能够有效改善老年失眠症患者的睡眠质量，其机制可能与调节血清SP、NPY、5-HT1A、5-HT2A水平有关。.

Natalisin (NTL) is a conserved neuropeptide, only present in insects, that has been reported to regulate their sexual activity. In this study, we investigated the involvement of NTL in the reproductive behaviors of a major invasive pest, Spodoptera frugiperda. We identified NTL precursor-encoded transcripts, and evaluated their transcript levels in different stages and tissues of S. frugiperda. The results showed that the NTL transcript level was expressed in both male and female pupae and both male and female adults in the later stage. It was highly expressed in male pupae, 3-day-old male and female adults, and 5-day-old male adults. In different tissues, the expression level is higher in the male and female adult brain and male testis. Immunohistochemical staining of the brain of S. frugiperda female and male adults revealed that three pairs of brain neurons of S. frugiperda adults of both sexes secreted and expressed NTL. To study the role of NTL in reproductive behaviors, NTL was silenced in S. frugiperda male and female adults by RNA interference (RNAi) technology, the results showed that silencing NTL could significantly affect the sexual activity behavior of the adults, reducing the calling rate of females, the courtship rate of males, and the mating rate. In summary, this study emphasizes the important role of NTL in regulating the mating behavior and sexual activity of S. frugiperda in both male and female adults, potentially laying a foundation to employ NTL as a new insect-specific target to control populations of pest insects.

Antimicrobial peptide (AMP) is an important component of crustaceans\' innate immune system. In this study, a short neuropeptide F (sNPF) gene (Pc-sNPF) and a Forkhead box O (FOXO) gene (PcFOXO) from Procambarus clarkii were identified. Analysis findings showed that the expression level of AMP genes differed between male and female P. clarkii. Furthermore, Pc-sNPF and PcFOXO were related to the sex dimorphism of AMP. Knockdown of Pc-sNPF in the eyestalk significantly upregulated the expression of PcFOXO and two anti-lipopolysaccharide factors (PcALF4 and PcALFL) in the intestine of P. clarkii. The expression of PcFOXO in the intestine of female P. clarkii was higher than in that of males. Results from RNA interference revealed that PcFOXO positively regulated the expression of PcALF4 and PcALFL in the intestine of male and female P. clarkii. In summary, our study showed that differences in Pc-sNPF expression in eyestalk of male and female P. clarkii leading to sex dimorphism of AMP expression in the intestine are mediated by the sNPF-FOXO-AMP signal pathway called the eyestalk-intestine axis.