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Wu M, Zhang Q, Shang L, Duan P. Microfluidics-derived hierarchical microparticles for the delivery of dienogest for localized endometriosis therapy. Acta Biomater 2024; 178:257-264. [PMID: 38387747 DOI: 10.1016/j.actbio.2024.02.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 01/19/2024] [Accepted: 02/12/2024] [Indexed: 02/24/2024]
Abstract
Drug therapy is one of the most important strategies for treating gynecological diseases. Local drug delivery is promising for achieving optimal regional drug exposure, considering the complex anatomy and dynamic environment of the upper genital tract. Here, we present microparticle-based microcarriers with a hierarchical structure for localized dienogest (DNG) delivery and endometriosis treatment. The microparticles were fabricated by microfluidics and consisted of photo-crosslinked bovine serum albumin hydrogel particles (D@P-B MPs) encapsulating DNG-loaded PLGA (poly lactic-co-glycolic acid) microspheres. Such design enables the microparticles to have sustained release capacity and cell adhesion ability. Based on this, the microparticles were applied for the treatment of peritoneal endometriosis through intraperitoneal injection. The performance of the microparticles in inhibiting the growth of ectopic lesions as well as their anti-inflammatory, anti-angiogenesis, and pelvic pain-relieving effects are well demonstrated in vivo. These findings indicate that the present hierarchical microparticles are good candidates for localized treatment of endometriosis and are promising for the management of gynecological diseases. STATEMENT OF SIGNIFICANCE: We prepared photo-crosslinked bovine serum albumin hydrogel particles (D@P-B MPs) encapsulating DNG-loaded PLGA microspheres using microfluidic electrospray. Such hierarchical structure provided multiple functions of the particles as drug carriers. The hierarchical microparticles not only supported the sustained release of drugs but also provided adhesion to human ectopic endometrial stromal cells. The hierarchical microparticles represented a localized treatment method for endometriosis and is promising for the management of gynecological diseases.
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Affiliation(s)
- Meiling Wu
- Department of Gynaecology, The Second Affiliated Hospital of Wenzhou Medical University, Zhejiang, 325000, China
| | - Qingfei Zhang
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang 325001, China
| | - Luoran Shang
- Department of Gynaecology, The Second Affiliated Hospital of Wenzhou Medical University, Zhejiang, 325000, China; Shanghai Xuhui Central Hospital, Zhongshan-Xuhui Hospital, and the Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology, Institutes of Biomedical Sciences), Fudan University, Shanghai 200032, China; Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang 325001, China.
| | - Ping Duan
- Department of Gynaecology, The Second Affiliated Hospital of Wenzhou Medical University, Zhejiang, 325000, China.
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Bashir ST, Redden CR, Raj K, Arcanjo RB, Stasiak S, Li Q, Steelman AJ, Nowak RA. Endometriosis leads to central nervous system-wide glial activation in a mouse model of endometriosis. J Neuroinflammation 2023; 20:59. [PMID: 36879305 PMCID: PMC9987089 DOI: 10.1186/s12974-023-02713-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 01/31/2023] [Indexed: 03/08/2023] Open
Abstract
BACKGROUND Chronic pelvic pain (CPP) is a common symptom of endometriosis. Women with endometriosis are also at a high risk of suffering from anxiety, depression, and other psychological disorders. Recent studies indicate that endometriosis can affect the central nervous system (CNS). Changes in the functional activity of neurons, functional magnetic resonance imaging signals, and gene expression have been reported in the brains of rat and mouse models of endometriosis. The majority of the studies thus far have focused on neuronal changes, whereas changes in the glial cells in different brain regions have not been studied. METHODS Endometriosis was induced in female mice (45-day-old; n = 6-11/timepoint) by syngeneic transfer of donor uterine tissue into the peritoneal cavity of recipient animals. Brains, spines, and endometriotic lesions were collected for analysis at 4, 8, 16, and 32 days post-induction. Sham surgery mice were used as controls (n = 6/timepoint). The pain was assessed using behavioral tests. Using immunohistochemistry for microglia marker ionized calcium-binding adapter molecule-1 (IBA1) and machine learning "Weka trainable segmentation" plugin in Fiji, we evaluated the morphological changes in microglia in different brain regions. Changes in glial fibrillary acidic protein (GFAP) for astrocytes, tumor necrosis factor (TNF), and interleukin-6 (IL6) were also evaluated. RESULTS We observed an increase in microglial soma size in the cortex, hippocampus, thalamus, and hypothalamus of mice with endometriosis compared to sham controls on days 8, 16, and 32. The percentage of IBA1 and GFAP-positive area was increased in the cortex, hippocampus, thalamus, and hypothalamus in mice with endometriosis compared to sham controls on day 16. The number of microglia and astrocytes did not differ between endometriosis and sham control groups. We observed increased TNF and IL6 expression when expression levels from all brain regions were combined. Mice with endometriosis displayed reduced burrowing behavior and hyperalgesia in the abdomen and hind-paw. CONCLUSION We believe this is the first report of central nervous system-wide glial activation in a mouse model of endometriosis. These results have significant implications for understanding chronic pain associated with endometriosis and other issues such as anxiety and depression in women with endometriosis.
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Affiliation(s)
- Shah Tauseef Bashir
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, 1207 W. Gregory Drive, Room 314 ASL, Urbana, IL, 61801, USA
| | - Catherine R Redden
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, 1207 W. Gregory Drive, Room 314 ASL, Urbana, IL, 61801, USA
| | - Kishori Raj
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, 1207 W. Gregory Drive, Room 314 ASL, Urbana, IL, 61801, USA
| | - Rachel B Arcanjo
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, 1207 W. Gregory Drive, Room 314 ASL, Urbana, IL, 61801, USA
| | - Sandra Stasiak
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, 1207 W. Gregory Drive, Room 314 ASL, Urbana, IL, 61801, USA
| | - Quanxi Li
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Andrew J Steelman
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, 1207 W. Gregory Drive, Room 314 ASL, Urbana, IL, 61801, USA
| | - Romana A Nowak
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, 1207 W. Gregory Drive, Room 314 ASL, Urbana, IL, 61801, USA.
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Neto AC, Santos-Pereira M, Abreu-Mendes P, Neves D, Almeida H, Cruz F, Charrua A. The Unmet Needs for Studying Chronic Pelvic/Visceral Pain Using Animal Models. Biomedicines 2023; 11:biomedicines11030696. [PMID: 36979674 PMCID: PMC10045296 DOI: 10.3390/biomedicines11030696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/13/2023] [Accepted: 02/16/2023] [Indexed: 03/03/2023] Open
Abstract
The different definitions of chronic pelvic/visceral pain used by international societies have changed over the years. These differences have a great impact on the way researchers study chronic pelvic/visceral pain. Recently, the role of systemic changes, including the role of the central nervous system, in the perpetuation and chronification of pelvic/visceral pain has gained weight. Consequently, researchers are using animal models that resemble those systemic changes rather than using models that are organ- or tissue-specific. In this review, we discuss the advantages and disadvantages of using bladder-centric and systemic models, enumerating some of the central nervous system changes and pain-related behaviors occurring in each model. We also present some drawbacks when using animal models and pain-related behavior tests and raise questions about possible, yet to be demonstrated, investigator-related bias. We also suggest new approaches to study chronic pelvic/visceral pain by refining existing animal models or using new ones.
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Affiliation(s)
- Ana Catarina Neto
- Experimental Biology Unit, Department of Biomedicine, Faculty of Medicine of University of Porto, 4200-319 Porto, Portugal
- I3S—Instituto de Investigação e Inovação em Saúde, University of Porto, 4200-135 Porto, Portugal
| | - Mariana Santos-Pereira
- Experimental Biology Unit, Department of Biomedicine, Faculty of Medicine of University of Porto, 4200-319 Porto, Portugal
- I3S—Instituto de Investigação e Inovação em Saúde, University of Porto, 4200-135 Porto, Portugal
| | - Pedro Abreu-Mendes
- I3S—Instituto de Investigação e Inovação em Saúde, University of Porto, 4200-135 Porto, Portugal
- Department of Urology, Centro Hospitalar de São João, 4200-319 Porto, Portugal
- Physiology and Surgery Department, Faculty of Medicine of University of Porto, 4200-319 Porto, Portugal
| | - Delminda Neves
- Experimental Biology Unit, Department of Biomedicine, Faculty of Medicine of University of Porto, 4200-319 Porto, Portugal
- I3S—Instituto de Investigação e Inovação em Saúde, University of Porto, 4200-135 Porto, Portugal
| | - Henrique Almeida
- Experimental Biology Unit, Department of Biomedicine, Faculty of Medicine of University of Porto, 4200-319 Porto, Portugal
- I3S—Instituto de Investigação e Inovação em Saúde, University of Porto, 4200-135 Porto, Portugal
- Ginecologia-Obstetrícia, Hospital-CUF Porto, 4100-180 Porto, Portugal
| | - Francisco Cruz
- I3S—Instituto de Investigação e Inovação em Saúde, University of Porto, 4200-135 Porto, Portugal
- Department of Urology, Centro Hospitalar de São João, 4200-319 Porto, Portugal
- Physiology and Surgery Department, Faculty of Medicine of University of Porto, 4200-319 Porto, Portugal
| | - Ana Charrua
- Experimental Biology Unit, Department of Biomedicine, Faculty of Medicine of University of Porto, 4200-319 Porto, Portugal
- I3S—Instituto de Investigação e Inovação em Saúde, University of Porto, 4200-135 Porto, Portugal
- Correspondence:
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HOSOTANI M, AKITA M, UEDA H, WATANABE T. The histopathological features of the surgical endometriosis model using systemic autoimmune disease-prone mice. J Vet Med Sci 2023; 85:1-8. [PMID: 36436950 PMCID: PMC9887222 DOI: 10.1292/jvms.22-0442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 11/20/2022] [Indexed: 11/29/2022] Open
Abstract
Endometriosis is a common gynecological disease that affects women of reproductive age in which the uterine endometrium grows outside the uterus. Origin of the ectopic endometrium is thought to be the retrograde endometrium through the oviducts. However, factors that determine the adherence and proliferation of the ectopic endometrium have not been revealed. Importantly, systemic autoimmune diseases are considered a key factor in the endometriosis onset. Herein, we established a surgical endometriosis rodent model using autoimmune disease-prone MRL/MpJ-Faslpr/lpr (MRL/lpr) and MRL/+ mice to provide basic evidence of the relationship between autoimmune disease and endometriosis. Endometriosis lesions were successfully induced in two regions after transplanting uterine tissues from donor mice into the peritoneal cavity of recipient mice: the peritoneum or adipose tissue around the transplantation point (proximal lesions) and the gastrosplenic ligament or intestinal mesentery far from the transplantation site (distal lesions). Distal lesions were observed only in MRL/lpr mice, whereas endometriosis lesions showed no genotype- or region-related differences in the histology and distribution of sex hormone receptors and T cells. In contrast, transplanted uterine tissues in donor MRL/lpr mice exhibited a large infiltration of T cells in the lamina propria. Splenomegaly was more common in recipient than that in donor MRL/lpr mice. These results suggest that the infiltration of endogenous T cells in the endometrium alters the growth features of ectopic endometrium, possibly affecting the severity of endometriosis in patients with systemic autoimmune diseases.
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Affiliation(s)
- Marina HOSOTANI
- Laboratory of Veterinary Anatomy, School of Veterinary Medicine, Rakuno Gakuen University, Hokkaido, Japan
| | - Machiko AKITA
- Laboratory of Veterinary Anatomy, School of Veterinary Medicine, Rakuno Gakuen University, Hokkaido, Japan
| | - Hiromi UEDA
- Laboratory of Veterinary Anatomy, School of Veterinary Medicine, Rakuno Gakuen University, Hokkaido, Japan
| | - Takafumi WATANABE
- Laboratory of Veterinary Anatomy, School of Veterinary Medicine, Rakuno Gakuen University, Hokkaido, Japan
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Maddern J, Grundy L, Harrington A, Schober G, Castro J, Brierley SM. A syngeneic inoculation mouse model of endometriosis that develops multiple comorbid visceral and cutaneous pain like behaviours. Pain 2022; 163:1622-1635. [PMID: 35050959 DOI: 10.1097/j.pain.0000000000002552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 11/29/2021] [Indexed: 11/26/2022]
Abstract
ABSTRACT Endometriosis is a chronic and debilitating condition, commonly characterised by chronic pelvic pain (CPP) and infertility. Chronic pelvic pain can be experienced across multiple pelvic organs, with comorbidities commonly effecting the bowel, bladder, and vagina. Despite research efforts into endometriosis pathophysiology, little is known about how endometriosis induces CPP, and as such, therapeutic interventions are lacking. The aim of this study was to characterise a syngeneic mouse model of endometriosis that mimics naturally occurring retrograde menstruation, thought to precede endometriosis development in patients, and determine whether these mice exhibit signs of CPP and altered behaviour. We characterised the development of endometriosis over 10 weeks following uterine tissue inoculation, measured in vivo and ex vivo hypersensitivity to mechanical stimuli across multiple visceral organs, and assessed alterations in animal spontaneous behaviour. We confirmed that inoculated uterine horn tissue formed into endometriosis lesions throughout the peritoneal cavity, with significant growth by 8 to 10 weeks post inoculation. Additionally, we found that mice with fully developed endometriosis displayed hypersensitivity evoked by (1) vaginal distension, (2) colorectal distension, (3) bladder distension, and (4) cutaneous thermal stimulation, compared to their sham counterparts. Moreover, endometriosis mice displayed alterations in spontaneous behaviour indicative of (5) altered bladder function and (6) anxiety. This model creates a foundation for mechanistical studies into the diffuse CPP associated with endometriosis and the development of targeted therapeutic interventions to improve the quality of life of women with endometriosis.
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Affiliation(s)
- Jessica Maddern
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Luke Grundy
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Andrea Harrington
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Gudrun Schober
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Joel Castro
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Stuart M Brierley
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
- Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia
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Tejada MA, Santos-Llamas AI, Escriva L, Tarin JJ, Cano A, Fernández-Ramírez MJ, Nunez-Badinez P, De Leo B, Saunders PTK, Vidal V, Barthas F, Vincent K, Sweeney PJ, Sillito RR, Armstrong JD, Nagel J, Gomez R. Identification of Altered Evoked and Non-Evoked Responses in a Heterologous Mouse Model of Endometriosis-Associated Pain. Biomedicines 2022; 10:biomedicines10020501. [PMID: 35203710 PMCID: PMC8962432 DOI: 10.3390/biomedicines10020501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 02/17/2022] [Indexed: 01/01/2023] Open
Abstract
The aim of this study was to develop and refine a heterologous mouse model of endometriosis-associated pain in which non-evoked responses, more relevant to the patient experience, were evaluated. Immunodeficient female mice (N = 24) were each implanted with four endometriotic human lesions (N = 12) or control tissue fat (N = 12) on the abdominal wall using tissue glue. Evoked pain responses were measured biweekly using von Frey filaments. Non-evoked responses were recorded weekly for 8 weeks using a home cage analysis (HCA). Endpoints were distance traveled, social proximity, time spent in the center vs. outer areas of the cage, drinking, and climbing. Significant differences between groups for von Frey response, climbing, and drinking were detected on days 14, 21, and 35 post implanting surgery, respectively, and sustained for the duration of the experiment. In conclusion, a heterologous mouse model of endometriosis-associated evoked a non-evoked pain was developed to improve the relevance of preclinical models to patient experience as a platform for drug testing.
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Affiliation(s)
- Miguel A. Tejada
- Research Unit on Women’s Health-INCLIVA, Institute of Health Research, 46010 Valencia, Spain; (M.A.T.); (A.I.S.-L.); (L.E.); (J.J.T.); (A.C.)
| | - Ana I. Santos-Llamas
- Research Unit on Women’s Health-INCLIVA, Institute of Health Research, 46010 Valencia, Spain; (M.A.T.); (A.I.S.-L.); (L.E.); (J.J.T.); (A.C.)
| | - Lesley Escriva
- Research Unit on Women’s Health-INCLIVA, Institute of Health Research, 46010 Valencia, Spain; (M.A.T.); (A.I.S.-L.); (L.E.); (J.J.T.); (A.C.)
| | - Juan J. Tarin
- Research Unit on Women’s Health-INCLIVA, Institute of Health Research, 46010 Valencia, Spain; (M.A.T.); (A.I.S.-L.); (L.E.); (J.J.T.); (A.C.)
- Department of Cellular Biology, Functional Biology and Physical Anthropology, University of Valencia, 46100 Burjassot, Spain
| | - Antonio Cano
- Research Unit on Women’s Health-INCLIVA, Institute of Health Research, 46010 Valencia, Spain; (M.A.T.); (A.I.S.-L.); (L.E.); (J.J.T.); (A.C.)
- Department of Pediatrics and Obstetrics and Gynecology, University of Valencia, 46010 Valencia, Spain;
| | - Maria J. Fernández-Ramírez
- Department of Pediatrics and Obstetrics and Gynecology, University of Valencia, 46010 Valencia, Spain;
- Department of Obstetrics and Gynecology, Hospital Clínico Universitario, 46010 Valencia, Spain
| | - Paulina Nunez-Badinez
- Bayer AG. Research & Early Development, Pharmaceuticals, Reproductive Health, Müllerstr. 178, 13342 Berlin, Germany; (P.N.-B.); (B.D.L.)
| | - Bianca De Leo
- Bayer AG. Research & Early Development, Pharmaceuticals, Reproductive Health, Müllerstr. 178, 13342 Berlin, Germany; (P.N.-B.); (B.D.L.)
| | - Philippa T. K. Saunders
- Centre for Inflammation Research, Queen’s Medical Research Institute, The University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK;
| | - Victor Vidal
- Faculty of Science, International University of La Rioja, Avda de la paz 137, 26006 Logrono, Spain;
| | | | - Katy Vincent
- Nuffield Department of Women’s and Reproductive Health, University of Oxford, Oxford OX1 2JD, UK;
| | - Patrick J. Sweeney
- Actual Analytics, 99 Giles Street, Edinburgh EH6 6BZ, UK; (P.J.S.); (R.R.S.); (J.D.A.)
| | - Rowland R. Sillito
- Actual Analytics, 99 Giles Street, Edinburgh EH6 6BZ, UK; (P.J.S.); (R.R.S.); (J.D.A.)
| | - James Douglas Armstrong
- Actual Analytics, 99 Giles Street, Edinburgh EH6 6BZ, UK; (P.J.S.); (R.R.S.); (J.D.A.)
- School of Informatics, University of Edinburgh, 10 Crichton Street, Edinburgh EH8 9AB, UK
| | - Jens Nagel
- Bayer AG. Research & Early Development, Pharmaceuticals, Exploratory Pathobiology, Aprather Weg 18a, 42096 Wuppertal, Germany;
| | - Raúl Gomez
- Research Unit on Women’s Health-INCLIVA, Institute of Health Research, 46010 Valencia, Spain; (M.A.T.); (A.I.S.-L.); (L.E.); (J.J.T.); (A.C.)
- Department of Pathology, University of Valencia, 46010 Valencia, Spain
- Correspondence:
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Castro J, Harrington AM, Chegini F, Matusica D, Spencer NJ, Brierley SM, Haberberger RV, Barry CM. Clodronate Treatment Prevents Vaginal Hypersensitivity in a Mouse Model of Vestibulodynia. Front Cell Infect Microbiol 2022; 11:784972. [PMID: 35118009 PMCID: PMC8803747 DOI: 10.3389/fcimb.2021.784972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 12/27/2021] [Indexed: 12/18/2022] Open
Abstract
IntroductionImproved understanding of vestibulodynia pathophysiology is required to develop appropriately targeted treatments. Established features include vulvovaginal hyperinnervation, increased nociceptive signalling and hypersensitivity. Emerging evidence indicates macrophage-neuron signalling contributes to chronic pain pathophysiology. Macrophages are broadly classified as M1 or M2, demonstrating pro-nociceptive or anti-nociceptive effects respectively. This study investigates the impact of clodronate liposomes, a macrophage depleting agent, on nociceptive signalling in a mouse model of vestibulodynia.MethodsMicroinjection of complete Freund’s adjuvant (CFA) at the vaginal introitus induced mild chronic inflammation in C57Bl/6J mice. A subgroup was treated with the macrophage depleting agent clodronate. Control mice received saline. After 7 days, immunolabelling for PGP9.5, F4/80+CD11c+ and F4/80+CD206+ was used to compare innervation density and presence of M1 and M2 macrophages respectively in experimental groups. Nociceptive signalling evoked by vaginal distension was assessed using immunolabelling for phosphorylated MAP extracellular signal-related kinase (pERK) in spinal cord sections. Hyperalgesia was assessed by visceromotor response to graded vaginal distension.ResultsCFA led to increased vaginal innervation (p < 0.05), increased pERK-immunoreactive spinal cord dorsal horn neurons evoked by vaginal-distension (p < 0.01) and enhanced visceromotor responses compared control mice (p < 0.01). Clodronate did not reduce vaginal hyperinnervation but significantly reduced the abundance of M1 and M2 vaginal macrophages and restored vaginal nociceptive signalling and vaginal sensitivity to that of healthy control animals.ConclusionsWe have developed a robust mouse model of vestibulodynia that demonstrates vaginal hyperinnervation, enhanced nociceptive signalling, hyperalgesia and allodynia. Macrophages contribute to hypersensitivity in this model. Macrophage-sensory neuron signalling pathways may present useful pathophysiological targets.
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Affiliation(s)
- Joel Castro
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, SA, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, SA, Australia
| | - Andrea M. Harrington
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, SA, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, SA, Australia
| | - Fariba Chegini
- Musculoskeletal Neurobiology Laboratory, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Adelaide, SA, Australia
| | - Dusan Matusica
- Pain and Sensory Neurobiology Laboratory, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Adelaide, SA, Australia
| | - Nick J. Spencer
- Visceral Neurophysiology Laboratory, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Adelaide, SA, Australia
| | - Stuart M. Brierley
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, SA, Australia
| | - Rainer V. Haberberger
- School of Biomedicine, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Christine M. Barry
- Musculoskeletal Neurobiology Laboratory, College of Medicine and Public Health, Flinders Health and Medical Research Institute (FHMRI), Flinders University, Adelaide, SA, Australia
- *Correspondence: Christine M. Barry,
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