Gas chromatography-mass spectrometric method-based urine metabolomic profile of rats with pelvic inflammatory disease

Extracellular succinate derived from ectopic milieu drives adhesion and implantation growth of ectopic endometrial stromal cells via the SUCNR1 signal in endometriosis

BACKGROUND

As a dual-function metabolite, succinate has emerged in cell function and plays a key signaling role in linking mitochondrial function to other cellular functions. Succinate accumulation in the cytoplasm is commonly associated with hypoxia in the microenvironment and immune cell activation. Extracellular succinate released into the microenvironment is considered an inflammatory alarm that can be sensed by its membrane receptor SUCNR1, which boosts proinflammatory responses and acts akin to classical hormones and cytokines. Succinate plays an important role in the development of inflammatory diseases. Whether succinate facilitates the progression of endometriosis (EMs), characterized by chronic inflammation and peritoneal adhesion, is worth exploring.

OBJECTIVE

We mimicked the ectopic milieu in vitro and in vivo to evaluate the main source and potential role of succinate in endometriosis. We assessed the molecular and functional effects of succinate on macrophages and peritoneal mesothelial cells in peritoneal cavity. The effect of succinate/SUCNR1 signaling on ectopic endometrial stromal cells (ESCs) was further explored in this study.

METHODS

In this study, we used targeted organic acid metabolomics analysis and in vitro assays to assess the potential accumulation of succinate in the peritoneal fluid of EMs patients. We examined its correlation with disease severity, Visual Analogue Scale, and the Endometriosis Fertility Index. Flow cytometry, enzyme linked immunosorbent assay, western blot assay, quantitative real-time PCR, and other molecular biology techniques were used to explore the potential mechanisms.

RESULTS

By mimicking the ectopic milieu, we constructed an in vitro co-culture system and found that M1 polarized macrophages and that the peritoneal mesothelial cell line (HMrSV5) mainly released succinate into their microenvironment and activated the succinate receptor (SUCNR1) signal, which further polarized the macrophages and significantly enhanced the invasive survival of ESCs, and the adhesion to the peritoneum. We further investigated the pathological effects of extracellular succinate in vivo using a xenograft mouse models of endometriosis.

CONCLUSIONS

Succinate-SUCNR1 signaling facilitates the creation of inflammatory cells and plays a vital role in EMs progression and peritoneal adhesion. Our work on the molecular mechanisms underlying succinate accumulation and function will help elucidate the phenotypic mysteries of pain and infertility in EMs. Video Abstract.

Chronic poor healing wounds of post cesarean scar diverticulum: Altered angiogenesis and immunobiology

Cesarean section (CS) scar diverticula (CSD) is an important cause impede further fecundity, with rather complicated pathophysiologic mechanisms and unclear etiopathogenesis. In this study, we detect the influences of CSD on the pregnancy outcomes in in-vitro fertilization (IVF) or intra-cytoplasmic sperm injection (ICSI) embryo transfer (ET) cycles, and further explore the mechanisms involved based on histopathology and immunology differences in endometrium between CSD and vaginal birth (VB) women. The CS group had significantly lower CLBR compared to NCS group. Histopathological analysis showed that the higher prevalent of CE is accompanied by excessive fibroblast proliferation at the lower segment of uterus and significantly exaggerated vascular proliferation in situ. Intrauterine inflammatory cytokines including IL-1α, IL-1β, IL-6, IL-8, TNF-α and SDF-1α were also increased in CSD group. The present data suggests impaired fecundity in CSD women undergoing IVF/ICSI treatment. Although the causal relationship is ambiguous, the potential mechanisms may involve persistent inflammatory response in the uterine cavity, active vascular proliferation accompanied with increased fibrosis which are responsible for poor chronic wound healing of CSD.

Analysis on clinical association of uterine scar diverticulum with subsequent infertility in patients underwent cesarean section

To evaluate the relationship between uterine cesarean scar diverticulum (CSD) and subsequent infertility in patients who underwent cesarean section, and determine the effects of pelvic fluid-releasing inflammations on infertility.A retrospective analysis was designed among patients with CSD who were admitted to our hospital from January 1, 2018 to December 31, 2019. A total of 60 patients with CSD and uterine fibroids or benign ovarian tumors who underwent cesarean section were included, and divided into the CSD group and control group. Baseline characteristics of all patients were collected, and the pelvic adhesion scores and the percents of tubal patency were evaluated. Furthermore, the postoperative clinical outcomes were followed up. The levels of inflammatory factors in pelvic fluid were tested using Elisa kits.Preoperative data indicated that the size of the uterine scar diverticulum was (1.68 ± 0.52) cm, the pelvic adhesion scores were higher in CSD group than control group (4.67 ± 0.90 vs 0.47 ± 0.90, P < .05), and 21 of 30 patients with unobstructed fallopian tubes. The levels of tumor necrosis factor-α, interleukin-1β, and interleukin-6 in patients with CSD were obviously higher than control group (P < .05). After the follow-up, the data displayed that no CSD was found in all patients, the time of menstrual period in patients with CSD was shortened to 7.80 ± 1.27 days, and the myometrial thickness at uterine scar was significantly increased (P < .05). Additionally, the pregnancy rate was increased, and 12 of 30 patients were repregnant. Correlation analysis showed that the levels of inflammatory factors (tumor necrosis factor-α, interleukin-1β, interleukin-6), the size of uterine scar diverticulum, and the myometrial thickness at uterine scar were significantly correlated with subsequent infertility (r = 0.307, 0.083, 0.147, 0.405, 0.291, P < .05).Uterine scar diverticulum repair could improve menstrual prolongation, increased the thickness of myometrium and repregnant rate. Subsequent infertility was positively correlated with uterine scar diverticulum and the levels of inflammatory factors.

Protective effects of Asiatic acid against pelvic inflammatory disease in rats

Asiatic acid (AA) is one of the major components of the Chinese herb Centella asiatica and exerts a variety of pharmacological activities. However, the pharmacological effects of AA on pelvic inflammatory disease (PID) remain unknown. The purpose of the present study was to investigate the therapeutic efficacy and potential mechanisms of AA on PID in rats. A total of 75 female Sprague Dawley rats were randomly divided into the following five groups: A control group; a PID group; a PID + AA 5 mg/kg group; a PID + AA 35 mg/kg group; and a PID + AA 75 mg/kg group. Changes in cytokine and chemokine levels, myeloperoxidase (MPO) activity, nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome and nuclear factor-κB (NF-κB) activation, oxidative stress and cleaved caspase-3 were measured. AA treatment significantly decreased the excessive production of cytokines and chemokines and suppressed MPO activity and the activation of NLRP3 inflammasome, NF-κB and caspase-3, as well as oxidative stress. These results suggest that AA exhibits potent anti-inflammatory and antioxidant effects in rats with pathogen-induced PID and that the mechanism of these anti-inflammatory effects may be associated with the suppression of NLRP3 inflammasome activation and the NF-κB pathway.

Metabonomic study of the protective effect of Fukeqianjin formula on multi-pathogen induced pelvic inflammatory disease in rats

Background

Fukeqianjin formula has been effectively used in the treatment of pelvic inflammatory disease (PID) and the related complications in clinic. Although there have been some studies about the underlying mechanism that focus on its anti-inflammatory and immunoregulatory activities. But the mechanism is still not fully understood. The aim of this study was to investigate the alteration of plasma metabolic profiles in PID rats and the regulatory effect of Fukeqianjin formula on potential biomarkers.

Methods

Pelvic inflammatory model was established by intrauterine inoculation of multiple pathogens combined with mechanical injury of endometrium. Rats were randomly divided into normal group, model group, azithromycin group, high-and low-dose of Fukeqianjin formula treatment group (FF-H, and FF-L, respectively). After 14 days of intragastric administration, the plasm levels of interleukin-1β (IL-1β) and nitric oxide (NO) were measured. To further recognize and identify potential biomarkers and metabolic pathways, an ultra-performance liquid chromatography-quadrupole-Exactive Orbitrap-mass spectrometry (UPLC-Q-Exactive Orbitrap-MS) metabonomic method combined with multivariate analyses including principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and orthogonal partial least squares discriminant analysis (OPLS-DA), was employed to analyze the metabolic profiling.

Results

Compared with normal group, the plasma levels of IL-1β and NO were significantly increased in the PID model group (P < 0. 05), and obviously decreased after high-dose intervention of Fukeqianjin formula (P < 0. 01). The PCA, PLS-DA and OPLS-DA analysis showed that PID rats were clearly separated from normal rats. Compared with the PID model group, the metabolite profiles of Fukeqianjin formula treatment group was gradually restored to normal. Meanwhile, 14 potential metabolite biomarkers, which were mainly related to the metabolic pathways of intervening glycerophospholipid metabolism, linoleic acid metabolism/alpha-linolenic acid metabolism, amino acid metabolism, arachidonic acid metabolism, and unsaturated fatty acids biosynthesis, have been identified. Fukeqianjin formula exerts good regulatory effect on the abnormal metabolism of PID rats.

Conclusions

Intrauterine inoculation of multiple pathogens combined with mechanical injury of endometrium could significantly disturb the plasma metabolic profiles of rats. Fukeqianjin formula has potential therapeutic effect on multi-pathogen-induced PID by ameliorating metabolism disorders and alleviating the inflammatory response.

Electronic supplementary material

The online version of this article (10.1186/s13020-018-0217-6) contains supplementary material, which is available to authorized users.

Antioxidative, anti-inflammatory and anti-apoptotic effects of ellagic acid in liver and brain of rats treated by D-galactose

Accumulating evidence has suggested that oxidative stress and apoptosis are involved in the ageing process. D-galactose (gal) has been reported to cause symptoms of ageing in rats, accompanied by liver and brain injuries. Our study aimed to investigate the potential antioxidative, anti-inflammatory and anti-apoptotic effects of ellagic acid and to explore how these effects act on rats in a D-gal-induced ageing model. Ageing was induced by subcutaneous injection of D-gal (100 mg/kg/d for 8 weeks). Ellagic acid was simultaneously administered to the D-gal-induced ageing rats once daily by intragastric gavage. Finally, the mental condition, body weight, organ index, levels of inflammatory cytokines, antioxidative enzymes, and liver function, as well as the expression of pro- and anti-apoptotic proteins, were monitored. Our results showed that ellagic acid could improve the mental condition, body weight, organ index and significantly decrease the levels of inflammatory cytokines, normalize the activities of antioxidative enzymes, and modulate the expression of apoptotic protein in ageing rats. In conclusion, the results of this study illustrate that ellagic acid was suitable for the treatment of some ageing-associated problems, such as oxidative stress, and had beneficial effects for age-associated diseases.

NanoLC MALDI MS/MS based quantitative metabolomics reveals the alteration of membrane biogenesis in oral cancer

We present a label-free untargeted metabolomics approach using nanoLC-MALDI MS/MS interface for the separation, identification and quantification of the metabolites from cancer biopsies.