1
|
Lu P, Lifshitz LM, Bellve K, ZhuGe R. TMEM16A in smooth muscle cells acts as a pacemaker channel in the internal anal sphincter. Commun Biol 2024; 7:151. [PMID: 38317010 PMCID: PMC10844222 DOI: 10.1038/s42003-024-05850-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 01/23/2024] [Indexed: 02/07/2024] Open
Abstract
Maintenance of fecal continence requires a continuous or basal tone of the internal anal sphincter (IAS). Paradoxically, the basal tone results largely from high-frequency rhythmic contractions of the IAS smooth muscle. However, the cellular and molecular mechanisms that initiate these contractions remain elusive. Here we show that the IAS contains multiple pacemakers. These pacemakers spontaneously generate propagating calcium waves that drive rhythmic contractions and establish the basal tone. These waves are myogenic and act independently of nerve, paracrine or autocrine signals. Using cell-specific gene knockout mice, we further found that TMEM16A Cl- channels in smooth muscle cells (but not in the interstitial cells of Cajal) are indispensable for pacemaking, rhythmic contractions, and basal tone. Our results identify TMEM16A in smooth muscle cells as a critical pacemaker channel that enables the IAS to contract rhythmically and continuously. This study provides cellular and molecular insights into fecal continence.
Collapse
Affiliation(s)
- Ping Lu
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Lawrence M Lifshitz
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Karl Bellve
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Ronghua ZhuGe
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA, USA.
| |
Collapse
|
2
|
Zacchè MM, Ghosh J, Liapis I, Chilaka C, Latthe P, Toozs-Hobson P. Anal incontinence following obstetric anal sphincter injury: Is there a difference between subtypes? A systematic review. Neurourol Urodyn 2023; 42:1455-1469. [PMID: 37431160 DOI: 10.1002/nau.25235] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 04/06/2023] [Accepted: 06/17/2023] [Indexed: 07/12/2023]
Abstract
AIMS Obstetric anal sphincter injury (OASI) is associated with long-term anal incontinence (AI). We aimed to address the following questions: (a) are women with major OASI (grade 3c and 4) at higher risk of developing AI when compared to women with minor OASI (grade 3a and 3b)? (b) is a fourth-degree tear more likely to cause AI over a third-degree tear? METHODS A systematic literature search from inception until September 2022. We considered prospective and retrospective cohort studies, cross-sectional and case-control studies without language restrictions. The quality was assessed by the Newcastle-Ottawa Scale and the Joanna Briggs Institute critical appraisal checklist. Risk ratios (RRs) were calculated to measure the effect of different grades of OASI. RESULTS Out of 22 studies, 8 were prospective cohort, 8 were retrospective cohort, and 6 were cross-sectional studies. Length of follow-up ranged from 1 month to 23 years, with the majority of the reports (n = 16) analysing data within 12-months postpartum. Third-degree tears evaluated were 6454 versus 764 fourth-degree tears. The risk of bias was low in 3, medium in 14 and high in 5 studies, respectively. Prospective studies showed that major tears are associated with a twofold risk of AI for major tears versus minor tears, while retrospective studies consistently showed a risk of fecal incontinence (FI) which was two- to fourfold higher. Prospective studies showed a trend toward worsening AI symptoms for fourth-degree tears, but this failed to reach statistical significance. Cross-sectional studies with long-term (≥5 years) follow-up showed that women with fourth-degree tear were more likely to develop AI, with an RR ranging from 1.4 to 2.2. Out of 3, 2 retrospective studies showed similar findings, but the follow-up was significantly shorter (≤1 year). Contrasting results were noted for FI rates, as only 5 out of 10 studies supported an association between fourth-degree tear and FI. CONCLUSIONS Most studies investigate bowel symptoms within few months from delivery. Data heterogeneity hindered a meaningful synthesis. Prospective cohort studies with adequate power and long-term follow-up should be performed to evaluate the risk of AI for each OASI subtype.
Collapse
Affiliation(s)
- Martino Maria Zacchè
- Department of Obstetrics and Gynaecology, Birmingham Women's Hospital, Birmingham, UK
| | - Jayasish Ghosh
- Department of Obstetrics and Gynaecology, Walsall Manor Hospital, Walsall, UK
| | - Ilias Liapis
- Department of Obstetrics and Gynaecology, Birmingham Women's Hospital, Birmingham, UK
| | - Chioma Chilaka
- Department of Obstetrics and Gynaecology, Birmingham Women's Hospital, Birmingham, UK
| | - Pallavi Latthe
- Department of Obstetrics and Gynaecology, Birmingham Women's Hospital, Birmingham, UK
| | - Philip Toozs-Hobson
- Department of Obstetrics and Gynaecology, Birmingham Women's Hospital, Birmingham, UK
| |
Collapse
|
3
|
Tian L, Ma C, Deng Z, Zhu T, Zhao X, He Y, Wei M, Feng J, Yu D. Treatment of postoperative intestinal dysfunction of hirschsprung's disease based on the principle of "anorectal balance". Front Surg 2022; 9:996455. [PMID: 36386515 PMCID: PMC9649898 DOI: 10.3389/fsurg.2022.996455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 10/06/2022] [Indexed: 09/14/2023] Open
Abstract
PURPOSE Radical surgery is the most effective treatment for Hirschsprung's disease. However, some children still have symptoms of intestinal dysfunction such as constipation, abdominal distension, and recurrent enterocolitis after operation. The purpose of this study was to evaluate treatment outcomes of postoperative intestinal dysfunction in children with Hirschsprung's disease by using the principle of "anorectal balance". METHODS The clinical data of postoperative intestinal dysfunction in children with Hirschsprung's disease in the single treatment group from July 2019 to July 2021 were retrospectively analyzed. All the enrolled children underwent botulinum toxin injection (2.5 U/kg); 3 to 6 months later, the injection was performed again; the children who had received more than two botulinum toxin injections underwent the internal sphincter myectomy. Anorectal manometry was performed routinely after operation, and abdominal distension and defecation were recorded. RESULTS A total of thirty children with postoperative intestinal dysfunction underwent radical surgery for Hirschsprung's disease were included in this study. Symptoms of constipation, abdominal distension and enterocolitis were improved after botulinum toxin injections in most children compared to before surgery (P < 0.01). After re-injection of botulinum toxin in twelve children, the frequency of defecation increased, the anal resting pressure decreased, and the clinical symptoms were relieved again (P < 0.05). Eleven children underwent internal sphincter myectomy, and the symptoms of constipation, abdominal distension and enterocolitis were significantly improved after the operation (P < 0.01). CONCLUSION Botulinum toxin injection and internal sphincter myectomy based on the principle of "anorectal balance" can effectively reduce the resting pressure of the anus and relieve intestinal dysfunction, and have satisfactory clinical effect.
Collapse
Affiliation(s)
- Li Tian
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Clinical Center of Hirschsprung's Disease and Allied Disorders, Wuhan, China
| | - Chensen Ma
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Clinical Center of Hirschsprung's Disease and Allied Disorders, Wuhan, China
| | - Zhengdong Deng
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Clinical Center of Hirschsprung's Disease and Allied Disorders, Wuhan, China
| | - Tianqi Zhu
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Clinical Center of Hirschsprung's Disease and Allied Disorders, Wuhan, China
| | - Xiang Zhao
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Clinical Center of Hirschsprung's Disease and Allied Disorders, Wuhan, China
| | - Ying He
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Clinical Center of Hirschsprung's Disease and Allied Disorders, Wuhan, China
| | - Mingfa Wei
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Clinical Center of Hirschsprung's Disease and Allied Disorders, Wuhan, China
| | - Jiexiong Feng
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Clinical Center of Hirschsprung's Disease and Allied Disorders, Wuhan, China
| | - Donghai Yu
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Clinical Center of Hirschsprung's Disease and Allied Disorders, Wuhan, China
| |
Collapse
|
4
|
New Findings at the Internal Anal Sphincter on Cadaveric Dissection and Review of Sphincter-Related Surgery in a Newer Prospective. Indian J Surg 2022. [DOI: 10.1007/s12262-022-03537-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022] Open
|
5
|
Mittal RK, Tuttle LJ. Anorectal Anatomy and Function. Gastroenterol Clin North Am 2022; 51:1-23. [PMID: 35135656 DOI: 10.1016/j.gtc.2021.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Anatomy of pelvic floor muscles has long been controversial. Novel imaging modalities, such as three-dimensional transperineal ultrasound imaging, MRI, and diffusion tensor imaging, have revealed unique myoarchitecture of the external anal sphincter and puborectalis muscle. High-resolution anal manometry, high-definition anal manometry, and functional luminal imaging probe are important new tools to assess anal sphincter and puborectalis muscle function. Increased understanding of the structure and function of anal sphincter complex/pelvic floor muscle has improved the ability to diagnose patients with pelvic floor disorders. New therapeutic modalities to treat anal/fecal incontinence and other pelvic floor disorders will emerge in the near future.
Collapse
Affiliation(s)
- Ravinder K Mittal
- Department of Medicine/Gastroenterology, University of California, San Diego, ACTRI, 9500 Gilman Drive, MC 0061, La Jolla, CA 92093-0990, USA.
| | - Lori J Tuttle
- Department of Medicine/Gastroenterology, University of California, San Diego, USA; San Diego State University, San Diego, CA, USA
| |
Collapse
|
6
|
Lu P, Chen J, Zhang C, Saur D, Baer CE, Lifshitz LM, Fogarty KE, ZhuGe R. Oscillating calcium signals in smooth muscle cells underlie the persistent basal tone of internal anal sphincter. J Cell Physiol 2021; 236:5937-5952. [PMID: 33452672 PMCID: PMC8132622 DOI: 10.1002/jcp.30279] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/29/2020] [Accepted: 12/31/2020] [Indexed: 02/05/2023]
Abstract
A persistent basal tone in the internal anal sphincter (IAS) is essential for keeping the anal canal closed and fecal continence; its inhibition via the rectoanal inhibitory reflex (RAIR) is required for successful defecation. However, cellular signals underlying the IAS basal tone remain enigmatic. Here we report the origin and molecular mechanisms of calcium signals that control the IAS basal tone, using a combination approach including a novel IAS slice preparation that retains cell arrangement and architecture as in vivo, 2-photon imaging, and cell-specific gene-modified mice. We found that IAS smooth muscle cells generate two forms of contractions (i.e., phasic and sustained contraction) and Ca2+ signals (i.e., synchronized Ca2+ oscillations [SCaOs] and asynchronized Ca2+ oscillations [ACaOs]) that last for hours. RyRs, TMEM16A, L-type Ca2+ channels, and gap junctions are required for SCaOs, which account for phasic contraction and 75% of sustained contraction. Nevertheless, only RyRs are required for ACaOs, which contribute 25% of sustained contraction. Nitric oxide, the primary neurotransmitter mediating the RAIR, blocks both types of Ca2+ signals, leading to IAS's full relaxation. Our results show that the oscillating nature of Ca2+ signals generates and maintains the basal tone without causing cytotoxicity to IAS. Our study provides insight into fecal continence and normal defecation.
Collapse
Affiliation(s)
- Ping Lu
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA
| | - Jun Chen
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA
| | - Chenghai Zhang
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute at Harvard Medical School, Boston, MA, USA
| | - Dieter Saur
- Department of Internal Medicine II, Klinikum rechts der Isar, Technische Universität München, München, Germany
| | - Christina E Baer
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA
- Sanderson Center for Optical Experimentation, University of Massachusetts Medical School, Worcester, MA, USA
| | - Lawrence M Lifshitz
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Kevin E Fogarty
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Ronghua ZhuGe
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA
| |
Collapse
|
7
|
Lee TH, Lee JS, Kim J, Kim JO, Kim HG, Jeon SR, Hong SJ, Cho YS, Park S. Spontaneous Internal Anal Sphincter Relaxation During High-resolution Anorectal Manometry Is Associated With Peripheral Neuropathy and Higher Charlson Comorbidity Scores in Patients With Defecatory Disorders. J Neurogastroenterol Motil 2020; 26:362-369. [PMID: 32403904 PMCID: PMC7329158 DOI: 10.5056/jnm19129] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 11/12/2019] [Accepted: 12/30/2019] [Indexed: 12/13/2022] Open
Abstract
Background/Aims We aimed to evaluate associations between comorbidities, peripheral neuropathy, and spontaneous internal anal sphincter relaxation (SAR) in patients with defecatory disorders. Methods A patient was considered to exhibit SAR during high-resolution anorectal manometry (HR-ARM) when the nadir pressure is < 15 mmHg and the time from onset to relaxation was ≥ 15 seconds in the resting pressure frame. A case-control study was performed using HR-ARM data collected from 880 patients from January 2010 to May 2015. We identified 23 cases with SAR (median age 75 years; 15 females; 12 fecal incontinence and 11 constipation). We compared HR-ARM values, Charlson index comorbidity scores, neuropathy, and the prevalence of diseases that potentially cause neuropathy between controls and SAR patients. Each SAR case was compared to 3 controls. Controls were selected to match the age, gender, and examination year of each SAR case. Results Compared to controls (26.1%), SAR patients (52.2%) exhibited a significantly higher frequency of fecal incontinence. SAR patients also had higher Charlson index scores (5 vs 4, P = 0.028). Nine of 23 SAR patients (39.1%) exhibited peripheral neuropathy— this frequency was higher than that for the control group (11.6%; P = 0.003). Diseases that potentially cause neuropathy were observed in 17 of 23 SAR cases and 32 of 69 controls (P = 0.022). Conclusions SAR develops in patients with constipation and fecal incontinence but is more common in patients with fecal incontinence. Our controlled observational study implies that SAR is associated with peripheral neuropathy and more severe comorbidities.
Collapse
Affiliation(s)
- Tae Hee Lee
- Institute for Digestive Research, Digestive Disease Center Soonchunhyang University College of Medicine, Seoul, Korea
| | - Joon Seong Lee
- Institute for Digestive Research, Digestive Disease Center Soonchunhyang University College of Medicine, Seoul, Korea
| | - Jeeyeon Kim
- Institute for Digestive Research, Digestive Disease Center Soonchunhyang University College of Medicine, Seoul, Korea
| | - Jin-Oh Kim
- Institute for Digestive Research, Digestive Disease Center Soonchunhyang University College of Medicine, Seoul, Korea
| | - Hyun Gun Kim
- Institute for Digestive Research, Digestive Disease Center Soonchunhyang University College of Medicine, Seoul, Korea
| | - Seong Ran Jeon
- Institute for Digestive Research, Digestive Disease Center Soonchunhyang University College of Medicine, Seoul, Korea
| | - Su Jin Hong
- Department of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon, Gyeonggi-do, Korea
| | - Young Sin Cho
- Division of Gastroenterology, Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan, Chungcheongnam-do, Korea
| | - Suyeon Park
- Department of biostatistics, Soonchunhyang University Seoul Hospital, Seoul, Korea
| |
Collapse
|
8
|
Xue W, Wang S, Zhao Z, Li Y, Shang A, Li D, Yang J, Wang T, Wang M. Short-term outcomes of laparoscopic intersphincteric resection with intraoperative radiotherapy using low-energy X-rays for primary locally advanced low rectal cancer: a single center experience. World J Surg Oncol 2020; 18:26. [PMID: 32013978 PMCID: PMC6998155 DOI: 10.1186/s12957-020-1799-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 01/21/2020] [Indexed: 11/30/2022] Open
Abstract
Background Even with the augmentative application of anal-preservation surgery in low rectal cancer, the role and indications of laparoscopic intersphincteric resection (Lap ISR) are still under debate, especially for T3 or node-positive (T3N0M0, T1–3N+M0) cancer, mainly due to the oncological safety and functional outcomes. INTRABEAM (Carl Zeiss, Germany) intraoperative radiotherapy (IORT) using low-energy X-rays features in accurate irradiation, less exposure, and reduced complications. Taking advantages of Lap ISR and INTRABEAM IORT, this innovative approach aims to increase the probability of the anal preservation with acceptable postoperative outcomes. Materials and methods From December 2015 to August 2019, we retrospectively analyzed the short-term outcomes of 12 patients evaluated preoperatively with T3 or node-positive (T3N0M0, T1–3N+M0) primary locally advanced low rectal cancer. They all had received Lap ISR and INTRABEAM IORT with a dose of 16–18 Gy applied by an applicator through the anus (natural orifice). Then, with no pre- or postoperative radiotherapy given, the patients were suggested to receive 6–8 cycles of the XELOX chemotherapy regimen (oxaliplatin, 130 mg/m2 and capecitabine, 1000 mg/m2). Results All patients achieved R0 resection. The median radiation time was 27 min and 15 s, and the mean radiative dose was 17.3 Gy (range 16–18 Gy). The median follow-up time was 18.5 months (range 3–45 months). Two patients experienced local recurrence. Two male patients experienced anastomotic stenosis. Furthermore, one of them experienced perianal abscess and the other one experienced pulmonary metastasis after refusing to receive chemotherapy. One female patient with internal anal sphincter invasion experienced distant metastases to the liver and gluteus maximus muscle 35 months after IORT. No acute radiation injuries or symptoms were observed. Although they experienced a reduction in anal function, every patient was satisfied with the postoperative outcomes. Conclusions For patients evaluated preoperatively with T3 or node-positive (T3N0M0, T1–3N+M0) primary locally advanced low rectal cancer, Lap ISR with INTRABEAM IORT may be a safe and feasible approach for anal preservation without compromising oncological outcomes.
Collapse
Affiliation(s)
- Wangsheng Xue
- Department of the General Surgery, The Second Hospital of Jilin University, Changchun, Jilin Province, China
| | - Shuang Wang
- Department of Dermatology, The Second Hospital of Jilin University, Changchun, Jilin Province, China
| | - Zeyun Zhao
- Department of the General Surgery, The Second Hospital of Jilin University, Changchun, Jilin Province, China
| | - Yongbo Li
- Department of the General Surgery, The Second Hospital of Jilin University, Changchun, Jilin Province, China
| | - An Shang
- Department of the General Surgery, The Second Hospital of Jilin University, Changchun, Jilin Province, China
| | - Donglin Li
- Department of the General Surgery, The Second Hospital of Jilin University, Changchun, Jilin Province, China
| | - Jianzheng Yang
- Department of Radiology, The Second Hospital of Jilin University, Changchun, Jilin Province, China
| | - Tiejun Wang
- Department of Radiology, The Second Hospital of Jilin University, Changchun, Jilin Province, China
| | - Min Wang
- Department of the General Surgery, The Second Hospital of Jilin University, Changchun, Jilin Province, China.
| |
Collapse
|
9
|
Pihl S, Blomberg M, Uustal E. Internal anal sphincter injury in the immediate postpartum period; Prevalence, risk factors and diagnostic methods in the Swedish perineal laceration registry. Eur J Obstet Gynecol Reprod Biol 2019; 245:1-6. [PMID: 31825790 DOI: 10.1016/j.ejogrb.2019.11.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 11/19/2019] [Accepted: 11/27/2019] [Indexed: 11/17/2022]
Abstract
Risk factors for obstetric external anal sphincter injury are well known. Maternal and obstetric risk factors for internal anal sphincter injury are not extensively studied. The rationale of this study was to evaluate the proportion of internal anal sphincter injury in women with external anal sphincter injury, diagnosed immediately after delivery. This study will assess whether there are additional risks for obstetric internal anal sphincter injury. OBJECTIVES The primary aim was to assess the proportion of internal anal sphincter injury immediately in women with an external sphincter injury and to evaluate maternal and obstetric risk factors for internal anal sphincter injury in women with an external anal sphincter injury only. A secondary aim was to relate the diagnostic methods used for obstetric perineal lacerations to the presence of an internal anal sphincter injury. STUDY DESIGN A registry study with data from the Swedish Perineal Laceration Registry 2014-2018. From the registry, the maternal and obstetric characteristics of 3,333 primiparous women with isolated external (N = 2,236) versus both external and internal (N = 1,097) anal sphincter injuries were studied, as were the methods used for examining the obstetric anal sphincter injuries. RESULTS In 32.9 % (1,097/3,333) of primiparous women with an external anal sphincter injury, an internal anal sphincter injury was diagnosed immediately after delivery. A perineal palpatory thickness of less than 10 mm was a diagnostic sign for internal sphincter injury. Well-known risk factors associated with obstetric anal sphincter injuries could not be confirmed as independent risk factors for internal sphincter injury. When the infant is born with an arm beside the head, there is an almost two-fold increased risk for internal sphincter injury. CONCLUSIONS Our main finding is that 32.9 % of women with external anal sphincter injury also have an internal anal sphincter injury. A palpable perineal thickness of less than 10 mm, a degree 4-laceration and an infant born with a hand by the head increases the risk of internal sphincter injury and should be a clinical warning sign.
Collapse
Affiliation(s)
- Sofia Pihl
- Department of Obstetrics and Gynaecology, and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.
| | - Marie Blomberg
- Department of Obstetrics and Gynaecology, and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Eva Uustal
- Department of Obstetrics and Gynaecology, and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| |
Collapse
|
10
|
Singh J, Mohanty I, Rattan S. In vivo magnetofection: a novel approach for targeted topical delivery of nucleic acids for rectoanal motility disorders. Am J Physiol Gastrointest Liver Physiol 2018; 314:G109-G118. [PMID: 29051187 PMCID: PMC5866375 DOI: 10.1152/ajpgi.00233.2017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In these studies, we developed a novel approach of in vivo magnetofection for localized delivery of nucleic acids such as micro-RNA-139-5p (miR-139-5p; which is known to target Rho kinase2) to the circular smooth muscle layer of the internal anal sphincter (IAS). The IAS tone is known to play a major role in the rectoanal continence via activation of RhoA-associated kinase (RhoA/ROCK2). These studies established an optimized protocol for efficient gene delivery using an assembly of equal volumes of in vivo PolyMag and miR139-5p or anti-miR-139-5p (100 nM each) injected in the circular smooth muscle layer in the pinpointed areas of the rat perianal region and then incubated for 20 min under magnetic field. Magnetofection efficiency was confirmed and analyzed by confocal microscopy of FITC-tagged siRNA. Using physiological and biochemical approaches, we investigated the effects of miR-139-5p and anti-miR-139-5p on basal intraluminal IAS pressure (IASP), fecal pellet count, IAS tone, agonist-induced contraction, contraction-relaxation kinetics, and RhoA/ROCK2 signaling. Present studies demonstrate that magnetofection-mediated miR-139-5p delivery significantly decreased RhoA/ROCK2, p-MYPT1, and p-MLC20 signaling, leading to decreases in the basal IASP and IAS tone and in rates of contraction and relaxation associated with increase in fecal pellet output. Interestingly, anti-miR-139-5p transfection had opposite effects on these parameters. Collectively, these data demonstrate that magnetofection is a promising novel method of in vivo gene delivery and of nucleotides to the internal anal sphincter for the site-directed and targeted therapy for rectoanal motility disorders. NEW & NOTEWORTHY These studies for the first time demonstrate the success of topical in vivo magnetofection (MF) of nucleic acids using perianal injections. To demonstrate its effectiveness, we used FITC-tagged siRNA via immunofluorescence microcopy and functional and biochemical evidence using miR-139-5p (which is known to target ROCK2). In conclusion, MF allows safe, convenient, efficient, and targeted delivery of oligonucleotides such as siRNAs and microRNAs. These studies have direct therapeutic implications in rectoanal motility disorders especially associated with IAS.
Collapse
Affiliation(s)
- Jagmohan Singh
- Department of Medicine, Division of Gastroenterology and Hepatology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Ipsita Mohanty
- Department of Medicine, Division of Gastroenterology and Hepatology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Satish Rattan
- Department of Medicine, Division of Gastroenterology and Hepatology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania
| |
Collapse
|