Exosomes Play an Important Role in the Progression of Plasma Cell Mastitis via the PI3K-Akt-mTOR Signaling Pathway

Novel insights: crosstalk with non-puerperal mastitis and immunity

The two primary types of non-puerperal mastitis (NPM) are granulomatous lobular mastitis (GLM) and plasma cell mastitis (PCM). Existing research indicates that immune inflammatory response is considered to be the core of the pathogenesis of GLM and PCM, and both innate and adaptive immune responses play an important role in the pathophysiology of PCM and GLM. However, the regulatory balance between various immune cells in these diseases is still unclear. Consequently, we present a comprehensive summary of the immune-related variables and recent advances in GLM and PCM.

MCC950 attenuates plasma cell mastitis in an MDSC-dependent manner

Plasma cell mastitis (PCM) is a sterile inflammatory condition primarily characterized by periductal inflammation and ductal ectasia. Currently, there is a lack of non-invasive or minimally invasive treatment option other than surgical intervention. The NLRP3 inflammasome has been implicated in the pathogenesis and progression of various inflammatory diseases, however, its involvement in PCM has not yet been reported. In this study, we initially observed the pronounced upregulation of NLRP3 in both human and mouse PCM tissue and elucidated the mechanism underlying the attenuation of PCM through inhibition of NLRP3. We established the PCM murine model and collected samples on day 14, when inflammation reached its peak, for subsequent research purposes. MCC950, an NLRP3 inhibitor, was utilized to effectively ameliorate PCM by significantly reducing plasma cell infiltration in mammary tissue, as well as attenuate the expression of pro-inflammatory cytokines including IL-1β, TNF-α, IL-2, and IL-6. Mechanistically, we observed that MCC950 augmented the function of myeloid-derived suppressor cells (MDSCs), which in turn inhibited the infiltration of plasma cells. Furthermore, it was noted that depleting MDSCs greatly compromised the therapeutic efficacy of MCC950. Collectively, our findings suggest that the administration of MCC950 has the potential to impede the progression of PCM by augmenting MDSCs both numerically and functionally, ultimately treating PCM effectively. This study provides valuable insights into the utilization of pharmacological agents for PCM treatment.

Pharmacological effects and mechanism of Kaihoujian Throat Spray (children's type) in the treatment of pediatric acute pharyngitis and tonsillitis

Context

Kaihoujian Throat Spray children's type (KHJSC) is a Chinese medicine prescription for treating pediatric acute pharyngitis and tonsillitis (APT). However, its relevant mechanisms remain unclear.

Objective

To investigate the pharmacological effects of KHJSC on APT in vitro and in vivo, and explore the possible mechanism and target proteins.

Materials and methods

The antiviral and antibacterial effects in vitro were evaluated by IC50 and MICs. Thirty-six Japanese white rabbits were averagely divided into control group, model group, amoxicillin group and 3 dose groups of KHJSC (720, 540 and 360 μL/kg/d). The model rabbits were injected with β-hemolytic Streptococcus solution into the tonsils for 2 consecutive days. KHJSC treatment started on the third day. The whole blood, serum, tonsil tissues and pharyngeal mucosa tissues were collected for routine blood tests, proteomic, ELISA and other tests on the sixth day.

Results

The IC50 of KHJSC on HCoV-229E, influenza PR8 and Ad3 were 1.99, 1.99 and 4.49 mg/mL, respectively; MICs of MDR-PA, MRSA and β-hemolytic Streptococcus were 350, 350, and 175 mg/mL. KHJSC markedly decreased the number of white blood cells, lymphocytes, neutrophils, and the level of IL-1β, IL-5, IL-6, IL-18, TNF-α and MCP-1; increased the content of IL-2 and IFN-γ. Proteomic analysis and ELISA revealed that PI3K-Akt signaling pathway, NF-κB signaling pathway and Toll-like receptor signaling pathway were the potential mechanisms of KHJSC against APT.

Discussion and conclusion

These results provided the reference and scientific basis for the application of KHJSC in clinic and further mechanisms study.

Identification of periductal mastitis and granulomatous lobular mastitis: a literature review

Background and Objective

Non-puerperal mastitis (NPM) is a breast disease with poor clinical manifestations, which seriously affects women's health and quality of life. Due to the low incidence rate of the disease and the paucity of related research, there is much misdiagnosis and mis-management of periductal mastitis (PDM) and granulomatous lobular mastitis (GLM). Therefore, understanding the differences between PDM and GLM, in terms of etiology and clinical manifestations, is crucial for patient treatment and prognosis. At the same time, choosing different treatment methods may not achieve the best treatment effect, so the appropriate treatment method can often reduce the patient's pain and reduce the recurrence of the patient's disease.

Methods

The PubMed database was searched for articles published from 1 January 1990 to 16 June 2022 using the following search terms: "non-puerperal mastitis", "periductal mastitis", "granulomatous lobular mastitis", "mammary duct ectasia", "idiopathic granulomatous mastitis", "plasma cell mastitis", and "identification". The key findings of the related literatures were analyzed and summarized.

Key Content and Findings

We systematically described the key points in the differential diagnosis, treatment, and prognosis of PDM and GLM. The use of different animal models for research and novel drugs to treat the disease were also described in this paper.

Conclusions

The key points in the differentiation of the two diseases are clearly explained, and the respective treatment options and prognosis are summarized.

Comparative Proteomic Analysis of Milk-Derived Extracellular Vesicles from Dairy Cows with Clinical and Subclinical Mastitis

Extracellular vesicles (EVs) are membranous vesicles found in biological fluids with essential functions. However, milk-derived EV proteins from clinical mastitis (CM) and subclinical mastitis (SM) cows have yet to be studied in detail. In this study, milk-derived EVs of CM, SM, and Healthy cows were extracted using a combination of acetic acid/ultracentrifugation and density gradient ultracentrifugation and analyzed using a shotgun proteomic by data-independent acquisition mode. A total of 1253 milk exosome proteins were identified and quantified. Differently enriched (DE) proteins were identified as given a Benjamini−Hochberg adjusted p < 0.05 and a fold change of at least 2. There were 53 and 1 DE proteins in milk-derived EVs from CM and SM cows compared with healthy cows. Protein S100-A9, Protein S100-A8, Chitinase-3-like protein 1, Haptoglobin, Integrin beta-2, and Chloride intracellular channel protein 1 were more abundant in the CM group (adjusted p < 0.05). Still, their enrichment in the SM group was not significant as in the Healthy group. The enrichment of DE proteins between CM and Healthy group was consistent with elevated GO (Gene Ontology) processes—defense response, defense response to Gram-positive bacterium, granulocyte chemotaxis also contributed to Reactome pathways—neutrophil degranulation, innate immune system, and antimicrobial peptides in the CM group. These results provide essential information on mastitis-associated proteins in milk-derived EVs and indicate the biological functions of milk-derived EVs proteins require further elucidation.

Study the Mechanism of Gualou Niubang Decoction in Treating Plasma Cell Mastitis Based on Network Pharmacology and Molecular Docking

Objective

Explore the potential molecular mechanisms behind the therapeutic functions of Gualou Niubang decoction (GLNBD) in the treatment of plasma cell mastitis (PCM) by network pharmacology and molecular docking.

Methods

GLNBD is a formula of Chinese traditional medicine consisting of 12 herbs. The potential active ingredients of GLNBD and their target genes were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform database, and PCM-related target genes were obtained from GeneCards, OMIM, and NCBI databases, using R language to obtain intersection targets; then, the STRING database and Cytoscape software were used to establish protein-protein interaction networks and herb ingredient target networks. DAVID was used to perform GO and KEGG pathway enrichment analyses on the intersection target. PyMoL-2.5.0 and AutoDock Tools-1.5.6 were used to verify the molecular docking.

Results

164 ingredients and 58 intersection targets were obtained in the treatment of PCM by GLNBD. Four key active compounds and four key proteins were identified. Then, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses showed that biological functions of potential target genes were associated with negative regulation of the apoptotic process, response to hypoxia, positive regulation of transcription, and DNA-templated, with related pathways involving the pathway in cancer, phosphatidylinositol 3-kinase (PI3K) Akt signaling pathway, and AGE-RAGE signaling pathway in diabetic complications. Moreover, the binding activities of key target genes and essential active compounds of Chinese herbal medicines in GLNBD were further validated by molecular docking. The results showed that the docking results were stable and had good binding ability.

Conclusion

This study suggested that four potential key active components, including quercetin, luteolin, fisetin, and kaempferol, were identified in GLNBD, which could interact with ALB, EGFR, IL-6, and VEGFA modulating the activation of the pathway in cancer, PI3K-Akt pathway, and AGE-RAGE signaling pathway in diabetic complications.

Current Understanding and Management of Plasma Cell Mastitis: Can We Benefit from What We Know?

BACKGROUND

Plasma cell mastitis (PCM), also known as mammary duct ectasia, is a chronic nonbacterial breast inflammation characterized by duct expansion and plasma cell infiltration. The severe and intense clinical manifestations profoundly affect the quality of life of female patients. Although the pathological process of PCM is known to include four stages (duct dilatation, inflammation, abscess and fistula), there is still lack of imaging techniques and serum markers with high specificity in clinical practice. Due to recurrent acute attacks and the prolonged healing process of the disease, most patients choose to accept mastectomy.

SUMMARY

We searched for studies, reports and reviews referring to PCM in the past 20 years; more than half of the results were related to animal studies, and little attention has been paid to human beings, which may explain the frequent misdiagnosis of PCM as breast cancer and the limited treatment options. This review focuses on the current diagnostic methods and markers for PCM and hierarchically discusses the typical clinical features, etiological causes and relevant molecular mechanisms of PCM.

KEY MESSAGES

We herein highlight the urgent need to develop more specific and sensitive biomarkers in the clinical laboratory. It will help to establish a standardized flowchart for the diagnosis and treatment of PCM in order to improve recovery for female patients.

Serum-derived exosomes from SD rats induce inflammation in macrophages through the mTOR pathway

Inhalation of beryllium and its compounds can cause lung injuries, resulting from inflammation and oxidative stress. Multivesicular bodies (MVB), such as exosomes, are membrane vesicles produced by early and late endosomes that mediate intercellular communications. However, the role of exosomes in beryllium toxicity has not been elucidated. This current study aimed to investigate the functional role of exosomes in lung injury resulting from beryllium sulfate (BeSO₄ ). Here, Sprague-Dawley (SD) rats were exposed to 4, 8, and 12 mg/kg BeSO₄ by non-exposed intratracheal instillation. Murine macrophage (RAW 264.7) cells were pretreated with 50 nmol/L rapamycin (an mTOR signaling pathway inhibitor) for 30 minutes, and then cultured for 24 hours with 100 μg/mL exosomes, which had been previously isolated from the serum of 12 mg/kg BeSO₄ -treated SD rats. Compared to those of the controls, exposure to BeSO₄ in vivo increased LDH activity, elevated levels of inflammatory cytokines (IL-10, TNF-α and IFN-γ) alongside inflammation-related proteins expression (COX-2 and iNOS), and enhanced secretion of exosomes from the SD rat's serum. Moreover, the BeSO₄ -Exos-induced upregulation of LDH activity and inflammatory responses in RAW 264.7 cells can be alleviated following pretreatment with rapamycin. Collectively, these results suggest that serum exosomes play an important role in pulmonary inflammation induced by BeSO₄ in RAW 264.7 cells via the mTOR pathway.

Activation of C3 and C5 May Be Involved in the Inflammatory Progression of PCM and GM

Plasma cell mastitis (PCM) and granulomatous mastitis (GM) are the most common inflammatory diseases constituting nonbacterial mastitis (NBM). However, the pathogenesis of NBM remains unclear. In this study, risk factors for NBM were assessed, as well as the pathological features of PCM and GM. The levels of C3/C3a-C3aR and C5/C5a-C5aR1 of tissues were detected by IHC and WB. Exosomes were isolated from serum and identified by transmission electron microscopy. Then, C3 and C5 levels were detected in peripheral blood, and exosomes were assessed by flow cytometry and immunoelectron microscopy. Obesity and prolonged lactation were risk factors for NBM. The infiltration of plasma cells and lymphocytes around the dilated catheter in PCM and the formation of granulomatous structures in GM were the respective pathological features. C3/C3a-C3aR and C5/C5a-C5aR1 levels were elevated in PCM and GM tissue samples. There were no differences in peripheral blood levels of C3 and C5, while C3a and C5a were highly expressed in exosomes. These results suggest that the complement family is activated in PCM and GM, exosomes enrich C3a and C5a, and mediate the spread of inflammation. These findings provide new insights into the molecular mechanisms of PCM and GM and identify therapeutic targets.

Chinese herbal compound combined with western medicine therapy in the treatment of plasma cell mastitis: A protocol for systematic review and meta-analysis

BACKGROUND

Plasma cell mastitis (PCM) is a benign suppurative disease of the breast based on the expansion of mammary ducts and infiltration of plasma cells. It is relatively rare clinically, and its main manifestations include nonperiodic breast pain, nipple discharge, areola lump, nipple depression, nipple fistula, among others. Modern medicine is mainly surgical treatment, which is easy to recur. The clinical practice shows that the overall treatment of patients with TCM syndrome differentiation using oral medicine combined with western medicine therapy, combined internal and external treatment, can significantly improve the curative effect, prevent recurrence, has a certain therapeutic advantage, but lack of evidence of evidence-based medicine. The purpose of this study is to study the efficacy and safety of oral traditional Chinese medicine (TCM) combined with western medicine therapy in the treatment of PCM.

METHODS

Use computer to retrieve English databases (PubMed, Embase, Web of Science, the Cochrane Library) and Chinese databases (CNKI, Wan Fang, VIP, Chinese biomedical database), from the establishment of database to September 2020, for randomized controlled trials(RCTs) of oral TCM combined with western medicine therapy in the treatment of PCM, two researchers independently extracted the data and evaluated the quality of the included research, and meta-analysis was conducted on the included literatures using RevMan5.3 software.

RESULTS

This study evaluated the efficacy and safety of oral TCM combined with western medicine therapy in the treatment of PCM from the aspects of effective rate, symptom score, recurrence rate, adverse reaction rate, and patient satisfaction.

CONCLUSION

This study will provide reliable evidence-based evidence for the clinical application of oral TCM combined with western medicine therapy in the treatment of PCM.

ETHICS AND DISSEMINATION

The purpose of this study is to sort out and analyze the literature. This systematic review also does not involve endangering participant rights. Ethical approval was not required. The results may be published in a peer-reviewed journal or disseminated at relevant conferences. OSF REGISTRATION NUMBER:: doi 10.17605/OSF.IO/K9A78.