A topical Chinese herbal inhibits pruritus and skin inflammation via neural TRPM8 in atopic dermatitis

Author links open overlay panelYao Chen ^a†, Ziyuan Tang ^a†, Zhiyao Han ^a, Mingyang Wang ^a, Xinran Li ^a, Luying Lai ^a, Pingzheng Zhou ^a,b, Fang Wang ^c,d, Fengxian Li ^a,e,**,‡

^aDepartment of Anesthesiology, Zhujiang Hospital, Southern Medical University, Guangzhou, China
^bGuangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China
^cDepartment of Dermatology, Dermatology Hospital, Southern Medical University, Guangzhou, China
^dGuangdong Provincial Key Laboratory of Brain Function and Disease, Guangzhou, China
^eKey Laboratory of Mental Health of the Ministry of Education, Guangdong Province Key Laboratory of Psychiatric Disorders, Southern Medical University, Guangzhou, China

Received 7 September 2024, Revised 12 February 2025, Accepted 15 February 2025, Available online 16 February 2025, Version of Record 21 February 2025.

Abstract

Background

Atopic dermatitis (AD) is a chronic, itchy, and inflammatory skin disease. The neuroimmune concept of itch involves aberrant immune responses and neural activities. Chinese herbal medicine has been demonstrated to alleviate AD symptoms, but the underlying mechanisms remain not fully understand.

Purpose

Chushizhiyang (CS) ointment is a topical treatment consisting of Chinese herbal ingredients. We aimed to study the underlying mechanism of CS on treating AD.

Method

To investigate the therapeutic efficacy of CS, we utilized a well-established atopic dermatitis mouse model, administering CS ointment topically to the ears. To unravel the underlying mechanisms, we employed a multifaceted approach, including behavioral assay, network pharmacology analysis, RNA-sequencing analysis, neural tracing, and calcium imaging. Additionally, transient receptor potential (TRP) M8-deficient mice were employed to validate the specific targets of CS.

Results

By employing a murine model of AD-like disease, we found that CS ointment can reduce skin inflammation and inhibit scratching behavior. Importantly, its capacity to alleviate itch-induced scratching surpasses that of topical steroid, a positive control treatment. The RNA-sequencing analysis of the affected skin revealed that the differentially expressed genes were enriched in neuroactive pathways that include ion channels particularly TRPM8. Calcium imaging demonstrated that CS ointment is capable of activating TRPM8-positive sensory neurons. Using transgenic animals, we found that CS ointment exhibited its anti-inflammatory or anti-pruritic effects only when TRPM8 is functional intact. Additionally, CS treatment reduced neuronal activities in wild-type, rather than TRPM8-compromised animals.

Conclusion

Our findings suggest that topical Chinese herbals participate in neuroimmune mechanisms for AD-like disease via TRPM8.

Keywords

Atopic dermatitis, TRPM8, Pruritus, Inflammation, Chinese herb

Abbreviations

AD, atopic dermatitis; TRPM8, transient receptor potential M8; CS, Chushizhiyang ointment; EtOH, ethanol; HPLC, high performance liquid chromatography; TCMSP, traditional Chinese medicine systems pharmacology database; PPI, protein-protein interaction; GO, Gene Ontology; KEGG, Kyoto Encyclopedia of Genes and Genomes; IL-4, interleukin-4; IL-13, interleukin-13, IL-31, interleukin-31; IL-33, interleukin-33; CCL17, C-C Motif Chemokine Ligand 17; TSLP, thymic stromal lymphopoietin; eGFP, enhanced greed fluorescence protein; FG, fluoro-gold; DRG, dorsal root ganglion; TG, trigeminal ganglion; pERK, phosphorylated extracellular signal-regulated kinase;

^{Inhibitory immunoreceptors CD300a and CD300lf cooperate to regulate mast cell activation}

Gyemin noh

Hanbin Lee 1,2, Chigusa Nakahashi-Oda 1,3,�, Wenxin Lyu 1,2, Mamoru Tanaka1,4,
Akiyoshi Rai1,5, Yoichi Muramoto 1,5, Yaqiu Wang1,2, Seiya Mizuno6, Kazuko Shibuya 1,3, and
Akira Shibuya 1,3,7,�

Abstract
Mast cells (MCs) play a central role in allergic immune responses. MC activation is regulated by several inhibitory immunoreceptors. The CD300
family members CD300a and CD300lf recognize phospholipid ligands and inhibit the FcεRI-mediated activating signal in MCs. While CD300a
binds to phosphatidylserine (PS) to inhibit MCs activation, CD300lf function is less clear due to its ability to bind with ceramide and PS.
Moreover, it also remains blurring whether CD300a and CD300lf function independently, cooperatively, or by interfering with each other in regulating
MC activation. Using imaging and flow cytometric analyses of bone marrow-derived cultured MCs (BMMCs) from wild-type (WT),
Cd300a–/–, Cd300lf–/–, and Cd300a–/–Cd300lf–/– mice, we show that CD300lf and CD300a colocalized with PS externalized to the outer leaflet of
the plasma membrane with a polar formation upon activation, and CD300lf cooperates with CD300a to inhibit BMMCs activation. CD300lf also
colocalized with extracellular ceramide in addition to the internal PS on the cell surface, which results in stronger inhibition of MC activation than
CD300lf binding to PS alone. Similarly, although both Cd300a–/– and Cd300lf–/– mice showed decreased rectal temperatures compared with WT
mice in the model of passive systemic anaphylaxis, Cd300a–/–Cd300lf–/– mice showed lower rectal temperature than either Cd300a–/– or
Cd300lf–/– mice. Our results demonstrate the cooperativity of multiple inhibitory receptors expressed on MCs and their regulatory functions
upon binding to respective ligands.
Keywords: CD300a, CD300lf, ceramide, mast cells, phosphatidylserine

https://doi.org/10.1093/jimmun/vkae030

Mast Cells Initiate Type 2 Inflammation through Tryptase Released by MRGPRX2/MRGPRB2 Activation in Atopic Dermatitis

https://doi.org/10.1016/j.jid.2023.06.201

Tao Jia ¹³, Delu Che ¹²³, Yi Zheng ¹, Huan Zhang ¹, Yaxiang Li ¹, Tong Zhou ¹, Bin Peng ¹, Xueshan Du ¹, Longfei Zhu ¹, Jingang An ¹, Songmei Geng ¹

¹Department of Dermatology, Northwest Hospital, The Second Hospital Affiliated to Xi’an Jiaotong University, Xi’an, China

²Center for Dermatology Disease, Precision Medical Institute, Xi’an, China

Keywords

AD: Atopic Dermatitis, ADI: Atopic Dermatitis Index, MC: Mast Cell, TSLP: Thymic Stromal Lymphopoietin

TRESK background potassium channel regulates
MrgprA31 pruriceptor excitability, acute and
chronic itch

Dongyee Kim

http://dx.doi.org/10.1097/j.pain.0000000000003540

TPepPro: a deep learning model for predicting peptide–protein interactions

Xiaohong Jin, Zimeng Chen, Dan Yu, Qianhui Jiang, Zhuobin Chen, Bin Yan, Jing Qin, Yong Liu, Junwen Wang 

Bioinformatics, Volume 41, Issue 1, January 2025, btae708, https://doi.org/10.1093/bioinformatics/btae708

Published:

25 November 2024

 Article history

Abstract

Motivation

Peptides and their derivatives hold potential as therapeutic agents. The rising interest in developing peptide drugs is evidenced by increasing approval rates by the FDA of USA. To identify the most potential peptides, study on peptide-protein interactions (PepPIs) presents a very important approach but poses considerable technical challenges. In experimental aspects, the transient nature of PepPIs and the high flexibility of peptides contribute to elevated costs and inefficiency. Traditional docking and molecular dynamics simulation methods require substantial computational resources, and the predictive accuracy of their results remain unsatisfactory.

Results

To address this gap, we proposed TPepPro, a Transformer-based model for PepPI prediction. We trained TPepPro on a dataset of 19,187 pairs of peptide-protein complexes with both sequential and structural features. TPepPro utilizes a strategy that combines local protein sequence feature extraction with global protein structure feature extraction. Moreover, TPepPro optimizes the architecture of structural featuring neural network in BN-ReLU arrangement, which notably reduced the amount of computing resources required for PepPIs prediction. According to comparison analysis, the accuracy reached 0.855 in TPepPro, achieving an 8.1% improvement compared to the second-best model TAGPPI. TPepPro achieved an AUC of 0.922, surpassing the second-best model TAGPPI with 0.844. Moreover, the newly developed TPepPro identify certain PepPIs that can be validated according to previous experimental evidence, thus indicating the efficiency of TPepPro to detect high potential PepPIs that would be helpful for amino acid drug applications.

Availability and implementation

The source code of TPepPro is available at https://github.com/wanglabhku/TPepPro.

Apigenin ameliorates inflamed ulcerative colitis by regulating mast cell degranulation via the PAMP-MRGPRX2 feedback loop

https://doi.org/10.1016/j.phymed.2025.156564

Yihan Huang ^a†, Na Wang ^b†, Xiaolan Ji ^a, Shiqiong Luo ^a, Ling Gong ^a, Chenrui Zhao ^a, Guodong Zheng ^a, Rui Liu ^a, Tao Zhang ^a

^aSchool of Pharmacy, Health Science Center, Xi’an Jiaotong University, Xi’an 710061, China

^bDepartment of Otolaryngology, Affiliated Hospital of North China University of Science and Technology, Tangshan 063000, China

Highlights

• MrgprB2-mediated mast cell degranulation is critical for the persistence of inflammation in colitis.
• PAMP-MrgprB2-induced pro-inflammatory positive feedback loop is critical for inflammation.
• Apigenin reduces inflammatory symptoms and improves colon damage and inflammatory cell infiltration.
• Apigenin inhibited degranulation of mast cell and carboxypeptidase A3 levels.
• Apigenin ameliorating ulcerative colitis via MRGPRX2.

Keywords

Ulcerative colitis, Mast cells, Carboxypeptidase A3, Apigenin, MRGPRX2

Processing of pain and itch information by modality-specific neurons within the anterior cingulate cortex in mice

Hyoung-Gon Ko 1,2 ,HyunsuJung 3,4,9, Seunghyo Han1,9, Dong Il Choi4,9,
Chiwoo Lee4,9, Ja Eun Choi4,JihaeOh4,ChuljungKwak3,DaeHeeHan3,
Jun-Nyeong Kim1,SanghyunYe 4,JiahLee4,JaehyunLee4,KyungminLee 5,
Jae-Hyung Lee 6,MinZhuo7,8 & Bong-Kiun Kaang3,

Pain and itch are aversive sensations with distinct qualities, processed in
overlapping pathways and brain regions, including the anterior cingulate
cortex (ACC), which is critical for their affective dimensions. However, the
cellular mechanisms underlying their processing in the ACC remain unclear.
Here, we identify modality-specific neuronal populations in layer II/III of the
ACC in mice involved in pain and itch processing. Using a synapse labeling
tool, we show that pain- and itch-related neurons selectively receive synaptic
inputs from mediodorsal thalamic neurons activated by pain and itch stimuli,
respectively. Chemogenetic inhibition of these neurons reduced pruriception
ornociception without affecting the opposite modality. Conversely, activation
of these neurons did not enhance stimulus-specific responses but commonly
increased freezing-like behavior. These findings reveal that the processing of
itch and pain information in the ACC involves activity-dependent and
modality-specific neuronal populations, and that functionally distinct ACC neuronal subsets process pain and itch

Dual function of MrgprB2 receptor-dependent neural immune axis in chronic pain

Yucui Jiang ^a1 , Fan Ye ^d1 , Jian Zhang ^b1 , Yun Huang ^b , Yingxin Zong ^b , Feiyan Chen ^a , Yan Yang ^b , Chan Zhu ^b , Tao Yang ^c, Guang Yu ^b , Zongxiang Tang ^b

^aSchool of Chinese Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing 210023, China
^bSchool of Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing 210023, China
^cState Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China
^dCollege of Pharmacy, Jishou University, Jishou 416000, China

Received 26 March 2024, Revised 26 November 2024, Accepted 26 February 2025, Available online 28 February 2025.

Abstract

Introduction: Neuro-immune interactions have been recognized to be involved in the development of neuropathic pain induced by chemotherapeutic drugs (CINP). However, its role in pain resolution remains largely unknown, particularly concerning mast cells.

Objectives: To investigate the bidirectional modulation of mast cell Mas-related G protein-coupled receptor B2 (MrgprB2)-mediated neuro-immune interactions in CINP.

Methods: CINP model was established in wild-type mice, Mas-related G protein-coupled receptor D knockout (MrgprD^-/-) mice, mast cell-deficient mice, MrgprB2 knockout (MrgprB2^-/-) mice, and MrgprB2-Cre tdTomato mice. The role of MrgprB2 receptor in CINP was investigated by calcium imaging, cytokine antibody arrays, mining of single-cell sequencing databases, immunofluorescence, western blotting, co-immunoprecipitation (Co-IP), among other methodologies.

Results: We observed that cisplatin-induced allodynia was significantly inhibited in MrgprB2^-/- mice, which was attributed to the blockade of tryptase release and the suppression of upregulation of protease-activated receptor 2 (PAR2) expression in dorsal root ganglion (DRG). Thus, the activation of MrgprB2/Tryptase/PAR2 axis contributed to the development of cisplatin-induced pain. In addition, we also found that there was co-expression of PAR2 and MrgprD in DRG neurons. And activation of PAR2 can negatively regulate the expression of MrgprD, whether in a physiological state or in a chronic pain condition. Consequently, MrgprD expression was down-regulated by the activation of the MrgprB2/Tryptase/PAR2 axis during the later stages of CINP, which was associated with pain relief. Therefore, the activation of MrgprB2/Tryptase/PAR2 axis also contributed to the alleviation of cisplatin-induced pain. This finding was in line with the phenomenon that persistent stimulation by cisplatin did not cause a continuous increase in pain.

Conclusions: Our research elucidated the bidirectional modulation of MrgprB2-dependent neural immune axis in CINP. This study emphasized that MrgprB2 is a critical target for early intervention in CINP, and highlighted the necessity of considering the mechanism differences at different stages in pain management.

Keywords: CINP; MrgprB2 receptor; MrgprD receptor; PAR2 receptor.

Scratching promotes allergic inflammation and host defense via neurogenic mast cell activation

Andrew W. Liu^1,2, Youran R. Zhang^1,2, Chien-Sin Chen^1,2, Tara N. Edwards^1,2, Sumeyye Ozyaman^1,2†,
Torben Ramcke^1,2, Lindsay M. McKendrick^1,2, Eric S. Weiss^1,2, Jacob E. Gillis^1,2, Colin R. Laughlin²‡,
Simran K. Randhawa², Catherine M. Phelps², Kazuo Kurihara^1,2, Hannah M. Kang^1,2,
Sydney-Lam N. Nguyen^1,2, Jiwon Kim3, Tayler D. Sheahan3§, Sarah E. Ross3,4, Marlies Meisel^2,5,
Tina L. Sumpter^1,2, Daniel H. Kaplan^1,2*

¹Department of Dermatology, University of Pittsburgh, Pittsburgh, PA, USA. ²Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA. ³Department of Anesthesiology, University of Pittsburgh, Pittsburgh, PA, USA. ⁴Pittsburgh Center for Pain Research, Pittsburgh, PA, USA. ⁵Cancer Immunology and Immunotherapy Program, UPMC Hillman Cancer Center, Pittsburgh, PA, USA.
*Corresponding author. Email: dankaplan@pitt.edu
†Present address: Department of Histology and Embryology, School of Medicine, Istanbul Medipol University, Istanbul, Turkey.
‡Present address: Department of Immunobiology, Yale University, New Haven, CT, USA.
§Present address: Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA.

Editor’s summary

Itch, the sensation that stimulates scratching behavior, is often triggered by skin irritants and inflammation. Liu et al. found that ablating itch-sensing neurons or physically preventing scratching decreased the inflammation associated with antigen-dependent mast cell responses in response to chemicals that induce allergic immune responses (see the Perspective by Ver Heul). Scratching promoted pain-sensing neurons to release a neuropeptide that stimulated mast cells, and this peptide hormone synergized with antigen-dependent activation to increase the mast cell’s degranulation and ability to produce inflammatory mediators. In a model of skin infection associated with antigen-specific mast cell responses, scratching contributed to decreasing the bacterial load. —Sarah H. Ross

MrgprX2 regulates mast cell degranulation through PI3K/AKT and PLCγ signaling in pseudo-allergic reactions

https://doi.org/10.1016/j.intimp.2021.108389

Fan Zhang ^ab, Fang Hong ^ab, Lu Wang ^ac, Renjie Fu ^a, Jin Qi ^a, Boyang Yu^ab

^aJiangsu Key Laboratory for TCM Evaluation and Translational Research, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 21198, China
^bResearch Center for Traceability and Standardization of TCMs, China Pharmaceutical University, Nanjing 211198, China
^cNanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese Medicine, China

Received 10 August 2021, Revised 27 October 2021, Accepted 9 November 2021, Available online 15 December 2021, Version of Record 15 December 2021.

Highlights

• •MrgprX2 is a key receptor for pseudo-allergic reactions.
• •PI3K/AKT signaling pathway and PLCγ are important downstream of MrgprX2.
• •Inhibiting PI3K/AKT signaling pathway and PLCγ remarkable weakened pseudo-allergic reactions both in vivo and in vitro.

Abstract

The G protein-coupled receptor MrgprX2 in mast cells is known to be a crucial receptor for pseudo-allergic reactions. MrgprX2 activation leads to elevated intracellular calcium levels and mast cell degranulation, but the underlying mechanism remains to be elucidated. Herein, we investigated the role of the phosphatidylinositol 3 kinase (PI3K)/serum-threonine kinase (AKT) signaling pathway and phospholipase C gamma (PLCγ) in mast cell degranulation mediated by MrgprX2 in LAD2 human-derived mast cells. The results showed that phosphorylated AKT (p-AKT) and PLCγ up-regulation were accompanied by an increase in intracellular calcium following activation of MrgprX2 by Compound 48/80, an inducer of mast cell degranulation. In contrast, p-AKT and PLCγ were down-regulated and intracellular calcium levels decreased after MrgprX2 knockdown. Mast cell degranulation was clearly suppressed; however, inhibiting PI3Kand PLCγ phosphorylation did not influence MrgprX2 expression. The increase in calcium concentration was suppressed and mast cell degranulation was weakened. Furthermore, by inhibiting PI3K and PLCγ phosphorylation in animals, the allergic symptoms caused by C48/80 were obviously reduced. We deduced that during the mast cell degranulation observed in pseudoallergic reactions, MrgprX2 regulated intracellular calcium levels via the PI3K/AKT and PLCγ pathways.

Keywords

Pseudo-allergic reactions, Mast cell, MRGPRX2, PI3K/AKT, PLCγ