Fig 1.
The expression of Sema 3A, Plexin A1 and NRP-1 in eutopic endometrium from patients with endometriosis and patients without endometriosis.
A: Immunohistochemical staining of three proteins in eutopic endometrium. EuE-EM: Eutopic Endometrium from patients with Endometriosis; EuE-NEM: Eutopic Endometrium from patients without Endometriosis (immunohistochemical stain, 200 × magnification). B and C: Semi-quantitative expression of Sema 3A, Plexin A1 and NRP-1 of glandular epithelial cells (B) as well as stromal cells (C) from eutopic endometrium from patients with endometriosis (EM) and without endometriosis (NEM). *P<0.05 (Mann–Whitney).
Fig 2.
Expression of Sema 3A, Plexin A1 and NRP-1 in peritoneal endometriotic lesions and deep infiltrating endometriotic lesions of uterosacral ligament.
A: Comparison of semi-quantitative expression of Sema 3A, Plexin A1 and NRP-1 of glandular epithelial cells between peritoneal endometriosis, deep infiltrating endometriosis of uterosacral ligament and eutopic endometrium from patients with endometriosis (EM) as well as without endometriosis (NEM). B: Comparison of semi-quantitative expression of Sema 3A, Plexin A1 and NRP-1 of stromal cells between peritoneal endometriosis, deep infiltrating endometriosis of uterosacral ligament and eutopic endometrium from patients with endometriosis (EM) as well as without endometriosis (NEM). C: Immunohistochemical staining of Sema 3A, Plexin A1 and NRP-1 in PEM and USL-EM. PEM: peritoneal endometriosis; USL-EM: deep infiltrating endometriosis of uterosacral ligament. (immunohistochemical stain, 200 × magnification) Mann-Whitney test: *P<0.05 (versus NEM); ** P<0.001 (versus EM); §P<0.05 (versus NEM); §§P<0.001(versus EM); NS, not significant.
Fig 3.
Comparison of total nerve fiber density and sympathetic nerve fiber density in peritoneal endometriotic specimens and healthy peritoneum.
(A) Total nerve fibers were positively stained by Anti-PGP 9.5 antibody. Comparison of the total nerve fiber density (NFD, NF/mm2) of endometriosis-associated nerve of peritoneal endometriosis (EAN-PEM), NFD of para-endometriotic nerve of peritoneal endometriosis (PEN-PEM) and NFD of nerve of peritoneum of control (N-PC). (B) Sympathetic nerve fibers were positively stained by Anti-TH antibody. Comparison of endometriosis-associated sympathetic NFD of peritoneal endometriosis (ESAN-PEM), para-endometriotic sympathetic NFD of peritoneal endometriosis (PESN-PEM) and sympathetic NFD of peritoneum of control (SN-PC). *P<0.05.
Fig 4.
Comparison of total nerve fiber density and sympathetic nerve fiber density in deep infiltrating endometriotic specimens of uterosacral ligament and healthy uterosacral ligament.
(A) Total nerve fibers were positively stained by Anti-PGP 9.5 antibody. Comparison of the total nerve fiber density (NFD, NF/mm2) of endometriosis-associated nerve of deep infiltrating endometriosis of uterosacral ligament (EAN-USL-EM), NFD of para-endometriotic nerve of deep infiltrating endometriosis of uterosacral ligament (PEN-USL-EM) and NFD of nerve of uterosacral ligament of control (N-USL-C). (B) Sympathetic nerve fibers were positively stained by Anti-TH antibody. Comparison of endometriosis-associated sympathetic NFD of USL-EM (ESAN-USL-EM), para-endometriotic sympathetic NFD of USL-EM (PESN-USL-EM) and sympathetic NFD of uterosacral ligament of control (SN-USL-C). *P<0.05.
Fig 5.
Immunofluorescence histochemical staining of the total nerve fiber and sympathetic nerve fiber in deep infiltrating endometriotic specimens of uterosacral ligament and healthy uterosacral ligament.
Total nerve fibers were orange-yellow stained by Anti-PGP 9.5 antibody (A: EAN-USL-EM; B: PEN-USL-EM; C: N-USL-C). Sympathetic nerve fibers were also orange-yellow stained by Anti-TH antibody (D: EASN-USL-EM; E: PESN-USL-EM; F: SN-USL-C). Ectopic endometrial glandular epithelial cells was stained in green by anti-Sema 3A antibody staining (A was the merge image of double staining of both Sema 3A and PGP 9.5, D was the merge image of double staining of both Sema 3A and TH), nuclei were stained in blue by DAPI staining. White triangle: orange-yellow stained nerve fibers. (Original magnification 200×)
Fig 6.
Relationship between immunostaining of Sema 3A in stromal cells of endometriosis, total endometriosis-associated nerve fiber density and severity of dysmenorrhea.
A and B: Patients with higher pain VAS score presents with lower Sema 3A HSCORE of stromal cells of peritoneal endometriosis (SC-PEM), but with higher PGP 9.5 (+) total nerve density. C and D: Patients with higher pain VAS score presents with lower Sema 3A HSCORE of stromal cells of deep infiltrating endometriosis of uterosacral ligament (SC-USL-EM), but with higher PGP 9.5 (+) total nerve fiber density. *P<0.05.
Fig 7.
Distribution pattern of total nerve fiber and sympathetic nerve fiber in endometriosis.
Relationship between nerve fiber density and Sema 3A expression in endometriosis.
Fig 8.
Modulation mechanisms of sympathetic innervation by different levels of Sema 3A.
(A) NPR-1 is a co-receptor of VEGFR2, which is involved in VEGF signaling; NRP-1 is also a receptor for Sema 3A, after triggered by Sema 3A, it binds to Plexin A1, forming a complex implicated in modulating sympathetic innervation. (B) When the concentration of Sema 3A is low, VEGF-NRP-1-VEGFR2 signaling is dominant, thus providing chemoattractive cues for sympathetic nerve outgrowth. (C) When Sema 3A is high expressed, it mainly triggers NPR-1-VEGFR2 signaling, producing chemorepulsive cues limiting sympathetic nerve outgrowth.