Relationship between Microvascular Density and Expression of Vascular Endothelial Growth Factor in Patients with Ovarian Endometriosis

Targeting NGF but not VEGFR1 or BDNF signaling reduces endometriosis-associated pain in mice

INTRODUCTION

Endometriosis is a chronic inflammatory disease that affects ∼10 % of women. A significant fraction of patients experience limited or no efficacy with current therapies. Tissue adjacent to endometriosis lesions often exhibits increased neurite and vascular density, suggesting that disease pathology involves neurotrophic activity and angiogenesis.

OBJECTIVES

We aim to evaluate the potential for key tyrosine-kinase-receptor-coupled neurotrophic molecules to contribute to endometriosis-associated pain in mice.

METHODS

Peritoneal fluid was collected from endometriosis patients undergoing surgery and the levels of NGF and VEGFR1 regulators (VEGFA, VEGFB, PLGF, and sVEGFR1) were quantified by ELISA. VEGFR1 regulator concentrations were used to calculate VEGFR1 occupancy. We used genetic depletion, neutralizing antibodies, and pharmacological approaches to specifically block neurotrophic ligands (NGF or BDNF) or receptors (VEGFR1, TRKs) in a murine model of endometriosis-associated pain. Endometriosis-associated pain was measured using von Frey filaments, quantification of spontaneous abdominal pain-related behavior, and thermal discomfort. Disease parameters were evaluated by lesion size and prevalence. To evaluate potential toxicity, we measured the effect of entrectinib dose and schedule on body weight, liver and kidney function, and bone structure (via micro-CT).

RESULTS

We found that entrectinib (pan-Trk inhibitor) or anti-NGF treatments reduced evoked pain, spontaneous pain, and thermal discomfort. In contrast, even though calculated receptor occupancy revealed that VEGFR1 agonist levels are sufficient to support signaling, blocking VEGFR1 via antibody or tamoxifen-induced knockout did not reduce pain or lesion size in mice. Targeting BDNF-TrkB with an anti-BDNF antibody also proved ineffective. Notably, changing dosing schedule to once weekly eliminated entrectinib-induced bone-loss without decreasing efficacy against pain.

CONCLUSIONS

This suggests NGF-TrkA signaling, but not BDNF-TrkB or VEGF-VEGFR1, mediates endometriosis-associated pain. Moreover, entrectinib blocks endometriosis-associated pain and reduces lesion sizes. Our results also indicated that entrectinib-like molecules are promising candidates for endometriosis treatment.

Herbal medicine (Hyeolbuchukeo-tang or Xuefu Zhuyu decoction) for treating primary dysmenorrhea: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Primary dysmenorrhea is a condition characterized by painful menstrual cramps that usually occurs in the absence of any identifiable pathological condition among menstruating women, with the prevalence estimates varying between 45% and 95%. Nonsteroidal anti-inflammatory drugs (NSAIDs) are considered as a standard treatment for primary dysmenorrhea; however, the failure rate of NSAIDs is often 20% to 25% and these drugs commonly cause adverse effects. In this review, we investigated the current evidence related to the effectiveness of Xuefu Zhuyu decoction (XZD) or Hyeolbuchukeo-tang, a traditional herbal formula, as a treatment for primary dysmenorrhea.

METHODS

Literature search was conducted about randomized controlled trials (RCTs) for XZD on primary dysmenorrhea. PubMed, Cochrane Library, Embase, China National Knowledge Infrastructure Database, Oriental Medicine Advanced Searching Integrated System, and other Chinese, Korean, Japanese databases were searched up to December 20, 2017. Two independent reviewers extracted and assessed the data. The main outcome domains were visual analogue scale (VAS) score and response rate.

RESULTS

Among 475 publications, 8 RCTs involving 1048 patients were finally included. Methodological quality of included RCTs was relatively low. In 4 add-on design studies, XZD plus western medication (WM) group showed better response rate as compared to the WM sole therapy (relative risk 1.18, 95% confidence interval [1.11, 1.25], P < .01). VAS score after the 3rd month of treatment in the XZD plus WM group was also lower than that in the WM group (mean difference -0.45, 95% confidence interval [-0.79, -0.12], P < .01). In 4 XZD versus WM design studies, XZD sole therapy showed better response rate than did WM sole therapy (relative risk 1.26, 95% confidence interval [1.06, 1.49], P < .01).

CONCLUSION

The existing trials showed a favorable effect of XZD for the management of primary dysmenorrhea. However, the efficacy of XZD on primary dysmenorrhea is not conclusive owing to the small number of studies and the high risk of bias. Large-scale, long-term RCTs with rigorous methodological input are needed to clarify the role of XZD for the management of primary dysmenorrhea.

TRIAL REGISTRATION NUMBER

CRD42016050447 in PROSPERO 2016.

Chronic pelvic pain in endometriosis: an overview

Chronic pelvic pain (CPP) could be considered nowadays a deep health problem that challenges physicians all over the world. This because its aetiology is still unclear, the course of the disease could vary a lot among different patients and through time in the same patient, and the response to treatments is not every time successful. Among women who underwent laparoscopy for CPP, endometriosis is found in about 1/3 of the cases, while only 25% of women with histological confirmed endometriosis are asymptomatic. A wide range of variables may exert their influence on the resulting pain syndrome in endometriosis; for example, score according to American society for reproductive medicine (rASRM), size of the sub-peritoneal and pelvic wall implants, Douglas obliteration, previous surgery. It is widely accepted nowadays that central nervous system (CNS) and peripheral nervous system (PNS) seems to influence each other and this interconnection play a key role in pain modulation. Moreover, the phenomena induced by endometriosis in the pelvis, including the breakdown of peritoneal homeostasis and the induction of the production of proinflammatory and proangiogenic cytokines, are responsible of altered innervations and modulation of pain pathways in these patients. There are many proposed medical and surgical approach to treat this painful syndrome, although there is necessity of more efforts to create new non-invasive strategies that set a more accurate diagnosis of the causes of endometriotic-related CPP, and therefore facilitate its eradication.